WorldWideScience

Sample records for workstation information packet

  1. Oak Ridge Environmental Information System (ORIES) site workstation information packet for OREIS V1. 2

    Energy Technology Data Exchange (ETDEWEB)

    Voorhees, L.D.; McCord, R.A.; Durfee, R.C.; Land, M.L.; Olson, R.J.; Palmer, M.R.; Thomas, J.K.; Tinnel, E.P.; Zygmunt, B.C.

    1993-02-01

    The OREIS site workstation information packet was developed to accompany the OREIS site workstations, which are being delivered to the Environmental Restoration programs at the five DOE-OR sites. The packet is written specifically for the Site ER program staff at each of the five Sites who have been designated the OREIS contact by their ER program manager, and is not intended for general distribution. The packet provides an overview of the components of OREIS, points to more detailed information provided in the accompanying vendor and OREIS developed manuals, and includes information on training opportunities and user support.

  2. Oak Ridge Environmental Information System (ORIES) site workstation information packet for OREIS V1.2. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Voorhees, L.D.; McCord, R.A.; Durfee, R.C.; Land, M.L.; Olson, R.J.; Palmer, M.R.; Thomas, J.K.; Tinnel, E.P.; Zygmunt, B.C.

    1993-02-01

    The OREIS site workstation information packet was developed to accompany the OREIS site workstations, which are being delivered to the Environmental Restoration programs at the five DOE-OR sites. The packet is written specifically for the Site ER program staff at each of the five Sites who have been designated the OREIS contact by their ER program manager, and is not intended for general distribution. The packet provides an overview of the components of OREIS, points to more detailed information provided in the accompanying vendor and OREIS developed manuals, and includes information on training opportunities and user support.

  3. Information workstations in clinical pathology.

    Science.gov (United States)

    Spackman, K A

    1991-03-01

    Multitasking operating systems and expanding networks now permit smooth access to remote computers, peripherals, data, and information resources. Graphic user interfaces and productivity-enhancing software packages reduce the need for training and memorization of commands. New models of desktop computers based on "data-centered" software architecture can enhance workstation usefulness even more. Pathologists need to consider how these tools might improve access to and management of information and knowledge.

  4. [Monte Vista National Wildlife Refuge livestock grazing lawsuit : Information packet

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Packet of information from the Colorado Cattlemen's Association concerning the 1992 lawsuit filed against the Monte Vista National Wildlife Refuge. The suit was...

  5. Radiologist's clinical information review workstation interfaced with digital dictation system.

    Science.gov (United States)

    McEnery, K W; Suitor, C T; Hildebrand, S; Downs, R L

    2000-05-01

    Efficient access to information systems integrated into the radiologist's interpretation workflow will result in a more informed radiologist, with an enhanced capability to render an accurate interpretation. We describe our implementation of radStation, a radiologist's clinical information review workstation that combines a digital dictation station with a clinical information display. radStation uses client software distributed to the radiologist's workstation and central server software, both running Windows NT (Microsoft, Redmond, WA). The client system has integrated digital dictation software. The bar-code microphone (Boomerang, Dictaphone Corp, Stratford, CT) also serves as a computer input device forwarding the procedure's accession number to the server software. This initiates multiple queries to available legacy databases, including the radiology information system (RIS), laboratory information system, clinic notes, hospital discharge, and operative report system. The three-tier architecture then returns the clinical results to the radStation client for display. At the conclusion of the dictation, the digital voice file is transferred to the dictation server and the client notifies the RIS to update the examination status. The system is efficient in its information retrieval, with queries displayed in about 1 second. The radStation client requires less than 5 minutes of radiologist training in its operation, given that its control interface integrates with the well-learned dictation process. The telephone-based dictation system, which this new system replaced, remains available as a back-up system in the event of an unexpected digital dictation system failure. This system is well accepted and valued by the radiologists. The system interface is quickly mastered. The system does not interrupt dictation workflow with the display of all information initiated with examination bar-coding. This system's features could become an accepted model as a standard tool

  6. Scholastic Journalism Week, February 22-28, 1998. Information Packet.

    Science.gov (United States)

    Shipp, Leslie, Comp.; Shuman, Jim, Comp.

    This packet of information presents material for journalism educators to use in celebrating Scholastic Journalism Week, February 22-28, 1998. It contains a history of journalism in outline form and in newspaper article format; 13 classroom activities; 11 special activities for outside the classroom; a sample press release; a sample editorial;…

  7. Energy and Information Transfer Via Coherent Exciton Wave Packets

    Science.gov (United States)

    Zang, Xiaoning

    Electronic excitons are bound electron-hole states that are generated when light interacts with matter. Such excitations typically entangle with phonons and rapidly decohere; the resulting electronic state dynamics become diffusive as a result. However, if the exciton-phonon coupling can be reduced, it may be possible to construct excitonic wave packets that offer a means of efficiently transmitting information and energy. This thesis is a combined theory/computation investigation to design condensed matter systems which support the requisite coherent transport. Under the idealizing assumption that exciton-phonon entanglement could be completely suppressed, the majority of this thesis focuses on the creation and manipulation of exciton wave packets in quasi-one-dimensional systems. While each site could be a silicon quantum dot, the actual implementation focused on organic molecular assemblies for the sake of computational simplicity, ease of experimental implementation, potential for coherent transport, and promise because of reduced structural uncertainty. A laser design was derived to create exciton wave packets with tunable shape and speed. Quantum interference was then exploited to manipulate these packets to block, pass, and even dissociate excitons based on their energies. These developments allow exciton packets to be considered within the arena of quantum information science. The concept of controllable excitonic wave packets was subsequently extended to consider molecular designs that allow photons with orbital angular momentum to be absorbed to create excitons with a quasi-angular momentum of their own. It was shown that a well-defined measure of topological charge is conserved in such light-matter interactions. Significantly, it was also discovered that such molecules allow photon angular momenta to be combined and later emitted. This amounts to a new way of up/down converting photonic angular momentum without relying on nonlinear optical materials. The

  8. The Paradox of Giftedness and Autism: Packet of Information for Professionals (PIP)--Revised (2008)

    Science.gov (United States)

    Assouline, Susan G.; Nicpon, Megan Foley; Colangelo, Nicholas; O'Brien, Matthew

    2008-01-01

    This "Packet of Information for Professionals" (PIP) was developed for professionals who work with gifted and talented students who have an autism spectrum disorder (ASD). The purpose of PIP is to offer recommendations that will lead to a positive experience for twice-exceptional students who participate in specialized programs for…

  9. [From data entry to data presentation at a clinical workstation--experiences with Anesthesia Information Management Systems (AIMS)].

    Science.gov (United States)

    Benson, M; Junger, A; Quinzio, L; Michel, A; Sciuk, G; Fuchs, C; Marquardt, K; Hempelmannn, G

    2000-09-01

    Anesthesia Information Management Systems (AIMS) are required to supply large amounts of data for various purposes such as performance recording, quality assurance, training, operating room management and research. It was our objective to establish an AIMS that enables every member of the department to independently access queries at his/her work station and at the same time allows the presentation of data in a suitable manner in order to increase the transfer of different information to the clinical workstation. Apple Macintosh Clients (Apple Computer, Inc. Cupertino, California) and the file- and database servers were installed into the already partially existing hospital network. The most important components installed on each computer are the anesthesia documenting software NarkoData (ProLogic GmbH, Erkrath), HIS client software and a HTML browser. More than 250 queries for easy evaluation were formulated with the software Voyant (Brossco Systems, Espoo, Finland). Together with the documentation they are the evaluation module of the AIMS. Today, more than 20,000 anesthesia procedures are recorded each year at 112 decentralised workstations with the AIMS. In 1998, 90.8% of the 20,383 performed anesthetic procedures were recorded online and 9.2% entered postopeatively into the system. With a corresponding user access it is possible to receive all available patient data at each single anesthesiological workstation via HIS (diagnoses, laboratory results) anytime. The available information includes previous anesthesia records, statistics and all data available from the hospitals intranet. This additional information is of great advantage in comparison to previous working conditions. The implementation of an AIMS allowed to greatly enhance the quota but also the quality of documentation and an increased flow of information at the anesthesia workstation. The circuit between data entry and the presentation and evaluation of data, statistics and results directly

  10. Intraoperative non-record-keeping usage of anesthesia information management system workstations and associated hemodynamic variability and aberrancies.

    Science.gov (United States)

    Wax, David B; Lin, Hung-Mo; Reich, David L

    2012-12-01

    Anesthesia information management system workstations in the anesthesia workspace that allow usage of non-record-keeping applications could lead to distraction from patient care. We evaluated whether non-record-keeping usage of the computer workstation was associated with hemodynamic variability and aberrancies. Auditing data were collected on eight anesthesia information management system workstations and linked to their corresponding electronic anesthesia records to identify which application was active at any given time during the case. For each case, the periods spent using the anesthesia information management system record-keeping module were separated from those spent using non-record-keeping applications. The variability of heart rate and blood pressure were also calculated, as were the incidence of hypotension, hypertension, and tachycardia. Analysis was performed to identify whether non-record-keeping activity was a significant predictor of these hemodynamic outcomes. Data were analyzed for 1,061 cases performed by 171 clinicians. Median (interquartile range) non-record-keeping activity time was 14 (1, 38) min, representing 16 (3, 33)% of a median 80 (39, 143) min of procedure time. Variables associated with greater non-record-keeping activity included attending anesthesiologists working unassisted, longer case duration, lower American Society of Anesthesiologists status, and general anesthesia. Overall, there was no independent association between non-record-keeping workstation use and hemodynamic variability or aberrancies during anesthesia either between cases or within cases. Anesthesia providers spent sizable portions of case time performing non-record-keeping applications on anesthesia information management system workstations. This use, however, was not independently associated with greater hemodynamic variability or aberrancies in patients during maintenance of general anesthesia for predominantly general surgical and gynecologic procedures.

  11. VMware workstation

    CERN Document Server

    van Vugt, Sander

    2013-01-01

    This book is a practical, step-by-step guide to creating and managing virtual machines using VMware Workstation.VMware Workstation: No Experience Necessary is for developers as well as system administrators who want to efficiently set up a test environment .You should have basic networking knowledge, and prior experience with Virtual Machines and VMware Player would be beneficial

  12. Downlink Transmission of Short Packets: Framing and Control Information Revisited

    DEFF Research Database (Denmark)

    Trillingsgaard, Kasper Fløe; Popovski, Petar

    2017-01-01

    Cellular wireless systems rely on frame-based transmissions. The frame design is conventionally based on heuristics, consisting of a frame header and a data part. The frame header contains control information that provides pointers to the messages within the data part. In this paper, we revisit t...

  13. Time-frequency analysis of electroencephalogram series. III. Wavelet packets and information cost function

    Science.gov (United States)

    Blanco, S.; Figliola, A.; Quiroga, R. Quian; Rosso, O. A.; Serrano, E.

    1998-01-01

    Signals obtained during tonic-clonic epileptic seizures are usually neglected for analysis by the physicians due to the presence of noise caused by muscle contractions. Although noise obscures completely the recording, some information about the underlying brain activity can be obtained with wavelet transform by filtering those frequencies associated with muscle activity. One great advantage of this method over traditional filtering is that the filtered frequencies do not modify the pattern of the remanent ones. An accurate analysis of the different seizure stages was achieved using the wavelet packet method, and through the information cost function the brain dynamical behavior can be accessed.

  14. Engineering workstation: Sensor modeling

    Science.gov (United States)

    Pavel, M; Sweet, B.

    1993-01-01

    The purpose of the engineering workstation is to provide an environment for rapid prototyping and evaluation of fusion and image processing algorithms. Ideally, the algorithms are designed to optimize the extraction of information that is useful to a pilot for all phases of flight operations. Successful design of effective fusion algorithms depends on the ability to characterize both the information available from the sensors and the information useful to a pilot. The workstation is comprised of subsystems for simulation of sensor-generated images, image processing, image enhancement, and fusion algorithms. As such, the workstation can be used to implement and evaluate both short-term solutions and long-term solutions. The short-term solutions are being developed to enhance a pilot's situational awareness by providing information in addition to his direct vision. The long term solutions are aimed at the development of complete synthetic vision systems. One of the important functions of the engineering workstation is to simulate the images that would be generated by the sensors. The simulation system is designed to use the graphics modeling and rendering capabilities of various workstations manufactured by Silicon Graphics Inc. The workstation simulates various aspects of the sensor-generated images arising from phenomenology of the sensors. In addition, the workstation can be used to simulate a variety of impairments due to mechanical limitations of the sensor placement and due to the motion of the airplane. Although the simulation is currently not performed in real-time, sequences of individual frames can be processed, stored, and recorded in a video format. In that way, it is possible to examine the appearance of different dynamic sensor-generated and fused images.

  15. How users organize electronic files on their workstations in the office environment: a preliminary study of personal information organization behaviour

    Directory of Open Access Journals (Sweden)

    Christopher S.G. Khoo

    2007-01-01

    Full Text Available An ongoing study of how people organize their computer files and folders on the hard disk of their office workstations. A questionnaire was used to collect information on the subjects, their work responsibilities and characteristics of their workstations. Data on file and folder names and file structure were extracted from the hard disk using a computer program STG FolderPrint Plus, DOS command and screen capture. A semi-structured interview collected information on subjects' strategies in naming and organizing files and folders, and in locating and retrieving files. The data were analysed mainly through qualitative analysis and content analysis. The subjects organized their folders in a variety of structures, from broad and shallow to narrow and deep hierarchies. One to three levels of folders is common. The labels for first level folders tended to be task-based or project-based. Most subjects located files by browsing the folder structure, with searching used as a last resort. The most common types of folder names were document type, organizational function or structure, and miscellaneous or temporary. The frequency of folders of different types appear related to the type of occupation.

  16. Packet Tracer network simulator

    CERN Document Server

    Jesin, A

    2014-01-01

    A practical, fast-paced guide that gives you all the information you need to successfully create networks and simulate them using Packet Tracer.Packet Tracer Network Simulator is aimed at students, instructors, and network administrators who wish to use this simulator to learn how to perform networking instead of investing in expensive, specialized hardware. This book assumes that you have a good amount of Cisco networking knowledge, and it will focus more on Packet Tracer rather than networking.

  17. Microgravity Workstation and Restraint Evaluations

    Science.gov (United States)

    Chmielewski, C.; Whitmore, M.; Mount, F.

    1999-01-01

    Confined workstations, where the operator has limited visibility and physical access to the work area, may cause prolonged periods of unnatural posture. Impacts on performance, in terms of fatigue and posture, may occur especially if the task is tedious and repetitive or requires static muscle loading. The glovebox design is a good example of the confined workstation concept. Within the scope of the 'Microgravity Workstation and Restraint Evaluation' project, funded by the NASA Headquarters Life Sciences Division, it was proposed to conduct a series of evaluations in ground, KC-135 and Shuttle environments to investigate the human factors issues concerning confined/unique workstations, such as gloveboxes, and also including crew restraint requirements. As part of the proposed integrated evaluations, two Shuttle Detailed Supplementary Objectives (DSOs) were manifested; one on Space Transportation System (STS)-90 and one on STS-88. The DSO on STS-90 evaluated use of the General Purpose Workstation (GPWS). The STS-88 mission was planned to evaluate a restraint system at the Remote Manipulator System (RMS). In addition, KC- 1 35 flights were conducted to investigate user/workstation/restraint integration for long-duration microgravity use. The scope of these evaluations included workstations and restraints to be utilized in the ISS environment, but also incorporated other workstations/ restraints in an attempt to provide findings/requirements with broader applications across multiple programs (e.g., Shuttle, ISS, and future Lunar-Mars programs). In addition, a comprehensive electronic questionnaire has been prepared and is under review by the Astronaut Office which will compile crewmembers' lessons learned information concerning glovebox and restraint use following their missions. These evaluations were intended to be complementary and were coordinated with hardware developers, users (crewmembers), and researchers. This report is intended to provide a summary of the

  18. Designing and Implementing a Clinician Workstation

    Science.gov (United States)

    Tape, Thomas G.; Campbell, James R.

    1993-01-01

    We describe a simple approach to designing and quickly implementing a clinician workstation that helps practitioners access a variety of information resources. Using easy-to-use graphical tools, we installed a pilot workstation in our clinics. We were able to accommodate most of our users' needs and have a functional workstation installed in two months. This is the first step of an evolutionary process moving from separate tasks to full application integration.

  19. Technology Corner: Internet Packet Sniffers

    Directory of Open Access Journals (Sweden)

    Nick Flor

    2011-03-01

    Full Text Available A packet sniffer is a piece of software that allows a person to eavesdrop on computer communications over the internet.  A packet sniffer can be used as a diagnostic tool by network administrators or as a spying tool by hackers who can use it to steal passwords and other private information from computer users.  Whether you are a network administrator or information assurance specialist, it helps to have a detailed understanding of how packet sniffers work.  And one of the best ways to acquire such an understanding is to build and modify an actual packet sniffer.

  20. Vocational and Industrial Arts Packets.

    Science.gov (United States)

    Maine Audubon Society, Falmouth.

    This book is a teacher's guide to energy alternatives. It is divided into seven informational packets on the following topics: parabolic solar concentrators, solar flat plate collectors, wood as fuel, heat loss, bio-gas, wind, and water. Each packet contains background information for the teachers and learning activities for the students. The…

  1. The modern integrated anaesthesia workstation

    Directory of Open Access Journals (Sweden)

    Vijaya P Patil

    2013-01-01

    Full Text Available Over the years, the conventional anaesthesia machine has evolved into an advanced carestation. The new machines use advanced electronics, software and technology to offer extensive capabilities for ventilation, monitoring, inhaled agent delivery, low-flow anaesthesia and closed-loop anaesthesia. They offer integrated monitoring and recording facilities and seamless integration with anaesthesia information systems. It is possible to deliver tidal volumes accurately and eliminate several hazards associated with the low pressure system and oxygen flush. Appropriate use can result in enhanced safety and ergonomy of anaesthetic delivery and monitoring. However, these workstations have brought in a new set of limitations and potential drawbacks. There are differences in technology and operational principles amongst the new workstations. Understand the principles of operation of these workstations and have a thorough knowledge of the operating manual of the individual machines.

  2. The modern integrated anaesthesia workstation.

    Science.gov (United States)

    Patil, Vijaya P; Shetmahajan, Madhavi G; Divatia, Jigeeshu V

    2013-09-01

    Over the years, the conventional anaesthesia machine has evolved into an advanced carestation. The new machines use advanced electronics, software and technology to offer extensive capabilities for ventilation, monitoring, inhaled agent delivery, low-flow anaesthesia and closed-loop anaesthesia. They offer integrated monitoring and recording facilities and seamless integration with anaesthesia information systems. It is possible to deliver tidal volumes accurately and eliminate several hazards associated with the low pressure system and oxygen flush. Appropriate use can result in enhanced safety and ergonomy of anaesthetic delivery and monitoring. However, these workstations have brought in a new set of limitations and potential drawbacks. There are differences in technology and operational principles amongst the new workstations. Understand the principles of operation of these workstations and have a thorough knowledge of the operating manual of the individual machines.

  3. Information Theory Filters for Wavelet Packet Coefficient Selection with Application to Corrosion Type Identification from Acoustic Emission Signals

    Directory of Open Access Journals (Sweden)

    Marc M. Van Hulle

    2011-05-01

    Full Text Available The damage caused by corrosion in chemical process installations can lead to unexpected plant shutdowns and the leakage of potentially toxic chemicals into the environment. When subjected to corrosion, structural changes in the material occur, leading to energy releases as acoustic waves. This acoustic activity can in turn be used for corrosion monitoring, and even for predicting the type of corrosion. Here we apply wavelet packet decomposition to extract features from acoustic emission signals. We then use the extracted wavelet packet coefficients for distinguishing between the most important types of corrosion processes in the chemical process industry: uniform corrosion, pitting and stress corrosion cracking. The local discriminant basis selection algorithm can be considered as a standard for the selection of the most discriminative wavelet coefficients. However, it does not take the statistical dependencies between wavelet coefficients into account. We show that, when these dependencies are ignored, a lower accuracy is obtained in predicting the corrosion type. We compare several mutual information filters to take these dependencies into account in order to arrive at a more accurate prediction.

  4. Cataloguer\\'s workstation: implications for cataloguing theory and ...

    African Journals Online (AJOL)

    The significance of Technical Services Workstation (TSW) in both the effective retrieval of information and in cataloguing is discussed. A well defined future in the development and management of Technical Services Workstation is recommended. Keywords: developing countries, cataloguing, practice, theory, workstation

  5. Automated Analysis Workstation

    Science.gov (United States)

    1997-01-01

    Information from NASA Tech Briefs of work done at Langley Research Center and the Jet Propulsion Laboratory assisted DiaSys Corporation in manufacturing their first product, the R/S 2000. Since then, the R/S 2000 and R/S 2003 have followed. Recently, DiaSys released their fourth workstation, the FE-2, which automates the process of making and manipulating wet-mount preparation of fecal concentrates. The time needed to read the sample is decreased, permitting technologists to rapidly spot parasites, ova and cysts, sometimes carried in the lower intestinal tract of humans and animals. Employing the FE-2 is non-invasive, can be performed on an out-patient basis, and quickly provides confirmatory results.

  6. Election '88: Teacher Packet.

    Science.gov (United States)

    North Carolina State Dept. of Public Instruction, Raleigh. Div. of Social Studies Education.

    This materials packet contains information on teaching about the electoral process and the elections of 1988, and on participation in a mock election for students whose schools would take part in the 1988 North Carolina Mock Election. Suggestions for teachers' preparations are given, including a classroom skit and a mock candidates' election…

  7. Hoover Dam Learning Packet.

    Science.gov (United States)

    Bureau of Reclamation (Dept. of Interior), Washington, DC.

    This learning packet provides background information about Hoover Dam (Nevada) and the surrounding area. Since the dam was built at the height of the Depression in 1931, people came from all over the country to work on it. Because of Hoover Dam, the Colorado River was controlled for the first time in history and farmers in Nevada, California, and…

  8. Multipath packet switch using packet bundling

    DEFF Research Database (Denmark)

    Berger, Michael Stubert

    2002-01-01

    The basic concept of packet bundling is to group smaller packets into larger packets based on, e.g., quality of service or destination within the packet switch. This paper presents novel applications of bundling in packet switching. The larger packets created by bundling are utilized to extend...... switching capacity by use of parallel switch planes. During the bundling operation, packets will experience a delay that depends on the actual implementation of the bundling and scheduling scheme. Analytical results for delay bounds and buffer size requirements are presented for a specific scheduling...

  9. Extensible packet processing architecture

    Science.gov (United States)

    Robertson, Perry J.; Hamlet, Jason R.; Pierson, Lyndon G.; Olsberg, Ronald R.; Chun, Guy D.

    2013-08-20

    A technique for distributed packet processing includes sequentially passing packets associated with packet flows between a plurality of processing engines along a flow through data bus linking the plurality of processing engines in series. At least one packet within a given packet flow is marked by a given processing engine to signify by the given processing engine to the other processing engines that the given processing engine has claimed the given packet flow for processing. A processing function is applied to each of the packet flows within the processing engines and the processed packets are output on a time-shared, arbitered data bus coupled to the plurality of processing engines.

  10. Teleradiology network system and computer-aided diagnosis workstation using the web medical image conference system with a new information security solution

    Science.gov (United States)

    Satoh, Hitoshi; Niki, Noboru; Eguchi, Kenji; Ohmatsu, Hironobu; Kaneko, Masahiro; Kakinuma, Ryutaru; Moriyama, Noriyuki

    2011-03-01

    We have developed the teleradiology network system with a new information security solution that provided with web medical image conference system. In the teleradiology network system, the security of information network is very important subjects. We are studying the secret sharing scheme as a method safely to store or to transmit the confidential medical information used with the teleradiology network system. The confidential medical information is exposed to the risk of the damage and intercept. Secret sharing scheme is a method of dividing the confidential medical information into two or more tallies. Individual medical information cannot be decoded by using one tally at all. Our method has the function of RAID. With RAID technology, if there is a failure in a single tally, there is redundant data already copied to other tally. Confidential information is preserved at an individual Data Center connected through internet because individual medical information cannot be decoded by using one tally at all. Therefore, even if one of the Data Centers is struck and information is damaged, the confidential medical information can be decoded by using the tallies preserved at the data center to which it escapes damage. We can safely share the screen of workstation to which the medical image of Data Center is displayed from two or more web conference terminals at the same time. Moreover, Real time biometric face authentication system is connected with Data Center. Real time biometric face authentication system analyzes the feature of the face image of which it takes a picture in 20 seconds with the camera and defends the safety of the medical information. We propose a new information transmission method and a new information storage method with a new information security solution.

  11. Event-Triggered Control for Multiagent Systems with the Problem of Packet Losses and Communication Delays When Using the Second-Order Neighbors’ Information

    Directory of Open Access Journals (Sweden)

    Chuan Yan

    2014-01-01

    Full Text Available This paper mainly investigates the event-triggered control for discrete-time multiagent systems with the problem of packet losses and communication delays when both the first-order and the second-order neighbors’ information are used. Event-triggered control laws are adopted so as to reduce the frequency of individual actuation updating under the sampled-data framework for discrete-time agent dynamics. The communication graph is undirected and the loss of data across each communication link occurs at certain probability, which is governed by a Bernoulli process. It is found that the distributed consensus speeds up by using the second-order neighbors’ information when packet losses and communication delays occur. Numerical examples are given to demonstrate the effectiveness of the proposed methods.

  12. Creating Intelligent Computer Workstation of a Freight Officer in a Single Information Space of Railway Transport: Synergetic Approach

    Science.gov (United States)

    Malybaev, Saken K.; Malaybaev, Nurlan S.; Isina, Botakoz M.; Kenzhekeeva, Akbope R.; Khuangan, Nurbol

    2016-01-01

    The article presents the results of researches aimed at the creation of automated workplaces for railway transport specialists with the help of intelligent information systems. The analysis of tendencies of information technologies development in the transport network was conducted. It was determined that the most effective approach is to create…

  13. Operator interface design for a PACS primary diagnosis workstation

    Science.gov (United States)

    Freeman, Rick H.; Neubecker, Cynthia S.; Keller, Scott A.; Steinke, James E.

    1990-08-01

    One of the challenges to the PACS workstation designer is to cost effectively fulfill the range of requirements from those of the entry-level system to those of the fully digital hospital. The workstation must therefore support many of the functions of film-based image storage and image information systems. A primary diagnosis workstation must support rapid selection and viewing of patient examination folders. The user must easily and rapidly sequence through a stack of examinations. Activities such as printing films, archiving images, and retrieving older examinations must be initiated easily, without interfering with the diagnostic use of the workstation. Some of these functions are executed by the workstation itself while others are performed by service nodes on the PACS network. The workstation's user interface must make the architecture of the system transparent, providing access to the services while concealing the complexity of their accomplishment. This paper discusses the approach taken to the user interface of a commercial PACS primary diagnosis workstation. This workstation may be configured as an entry-level PACS or as a single workstation in a very complex system. Local image storage, retrieval, archiving and display functions will be described. Networking with modalities, image storage systems and image management systems will also be discussed.

  14. Design of Packet-Based Block Codes with Shift Operators

    Directory of Open Access Journals (Sweden)

    Jacek Ilow

    2010-01-01

    Full Text Available This paper introduces packet-oriented block codes for the recovery of lost packets and the correction of an erroneous single packet. Specifically, a family of systematic codes is proposed, based on a Vandermonde matrix applied to a group of k information packets to construct r redundant packets, where the elements of the Vandermonde matrix are bit-level right arithmetic shift operators. The code design is applicable to packets of any size, provided that the packets within a block of k information packets are of uniform length. In order to decrease the overhead associated with packet padding using shift operators, non-Vandermonde matrices are also proposed for designing packet-oriented block codes. An efficient matrix inversion procedure for the off-line design of the decoding algorithm is presented to recover lost packets. The error correction capability of the design is investigated as well. The decoding algorithm, based on syndrome decoding, to correct a single erroneous packet in a group of n=k+r received packets is presented. The paper is equipped with examples of codes using different parameters. The code designs and their performance are tested using Monte Carlo simulations; the results obtained exhibit good agreement with the corresponding theoretical results.

  15. Design of Packet-Based Block Codes with Shift Operators

    Directory of Open Access Journals (Sweden)

    Ilow Jacek

    2010-01-01

    Full Text Available This paper introduces packet-oriented block codes for the recovery of lost packets and the correction of an erroneous single packet. Specifically, a family of systematic codes is proposed, based on a Vandermonde matrix applied to a group of information packets to construct redundant packets, where the elements of the Vandermonde matrix are bit-level right arithmetic shift operators. The code design is applicable to packets of any size, provided that the packets within a block of information packets are of uniform length. In order to decrease the overhead associated with packet padding using shift operators, non-Vandermonde matrices are also proposed for designing packet-oriented block codes. An efficient matrix inversion procedure for the off-line design of the decoding algorithm is presented to recover lost packets. The error correction capability of the design is investigated as well. The decoding algorithm, based on syndrome decoding, to correct a single erroneous packet in a group of received packets is presented. The paper is equipped with examples of codes using different parameters. The code designs and their performance are tested using Monte Carlo simulations; the results obtained exhibit good agreement with the corresponding theoretical results.

  16. Hunger and Development [Issue Packet].

    Science.gov (United States)

    American Freedom from Hunger Foundation, Washington, DC.

    A variety of informational materials is compiled in this issue packet concentrating on hunger and development. They have been assembled to understand the issues associated with the facts of world hunger and to try to invent new forms of action and thought necessary to find the possibilities hidden in the hunger issue. Items include: (1) a fact and…

  17. A novel lost packets recovery scheme based on visual secret sharing

    Science.gov (United States)

    Lu, Kun; Shan, Hong; Li, Zhi; Niu, Zhao

    2017-08-01

    In this paper, a novel lost packets recovery scheme which encrypts the effective parts of an original packet into two shadow packets based on (2, 2)-threshold XOR-based visual Secret Sharing (VSS) is proposed. The two shadow packets used as watermarks would be embedded into two normal data packets with digital watermarking embedding technology and then sent from one sensor node to another. Each shadow packet would reveal no information of the original packet, which can improve the security of original packet delivery greatly. The two shadow packets which can be extracted from the received two normal data packets delivered from a sensor node can recover the original packet lossless based on XOR-based VSS. The Performance analysis present that the proposed scheme provides essential services as long as possible in the presence of selective forwarding attack. The proposed scheme would not increase the amount of additional traffic, namely, lower energy consumption, which is suitable for Wireless Sensor Network (WSN).

  18. The MAClinical Workstation Project at Georgetown University.

    Science.gov (United States)

    Broering, N C

    1991-07-01

    The intent of the MAClinical Workstation Project is to develop computer workstations for medical students of the sort they will use in future medical practice. The idea is to instill information query habits in the daily clinical activities of these young physicians-in-training. The Georgetown University Medical Center Library spearheads the project in conjunction with the School of Medicine. The library handles technical support, including software development, user training, equipment maintenance, and network installations. The project began in 1988 with nine Macintosh computers; today thirty machines are distributed throughout the Georgetown University Hospital conference rooms, faculty and resident offices, and at four affliated hospitals. The Macintosh computers are connected to the medical center's local area network (LAN) with access to the Integrated Academic Information Management System (IAIMS) and Library Information System (LIS) databases. The MAClinical workstations serve multiple educational purposes in the clinical setting. Primarily, students gain experience in medical informatics by using a variety of software systems installed at the stations: the H&P Writer, a history and physical system written in the C programming language, can be used by students to prepare the admission record on patients they examine; also, students can keep patient records, check findings against a diagnostic system, look up drugs and treatment protocols, develop medical sketches, and find additional information when needed in the medical literature.

  19. Next-Generation Telemetry Workstation

    Science.gov (United States)

    2008-01-01

    A next-generation telemetry workstation has been developed to replace the one currently used to test and control Range Safety systems. Improving upon the performance of the original system, the new telemetry workstation uses dual-channel telemetry boards for better synchronization of the two uplink telemetry streams. The new workstation also includes an Interrange Instrumentation Group/Global Positioning System (IRIG/GPS) time code receiver board for independent, local time stamping of return-link data. The next-generation system will also record and play back return-link data for postlaunch analysis.

  20. Arusha Rover Deployable Medical Workstation

    Science.gov (United States)

    Boswell, Tyrone; Hopson, Sonya; Marzette, Russell; Monroe, Gilena; Mustafa, Ruqayyah

    2014-01-01

    The NSBE Arusha rover concept offers a means of human transport and habitation during long-term exploration missions on the moon. This conceptual rover calls for the availability of medical supplies and equipment for crew members in order to aid in mission success. This paper addresses the need for a dedicated medical work station aboard the Arusha rover. The project team investigated multiple options for implementing a feasible deployable station to address both the medical and workstation layout needs of the rover and crew. Based on layout specifications and medical workstation requirements, the team has proposed a deployable workstation concept that can be accommodated within the volumetric constraints of the Arusha rover spacecraft

  1. Where To Access Statistical Information Relevant to Addressing Barriers to Learning: An Annotated Reference List. A Resource Aid Packet.

    Science.gov (United States)

    California Univ., Los Angeles. Center for Mental Health Schools.

    Key resources are listed that provide statistical information on youth, mental health, education, and related fields. Many of the references are to Web sites with current statistical reports. The advantage to this form of reporting is that the most recent information is available quickly. The topics covered give a broad perspective on youth, their…

  2. Fast packet switch architectures for broadband integrated services digital networks

    Science.gov (United States)

    Tobagi, Fouad A.

    1990-01-01

    Background information on networking and switching is provided, and the various architectures that have been considered for fast packet switches are described. The focus is solely on switches designed to be implemented electronically. A set of definitions and a brief description of the functionality required of fast packet switches are given. Three basic types of packet switches are identified: the shared-memory, shared-medium, and space-division types. Each of these is described, and examples are given.

  3. Optical Packet Switch Architectures

    Science.gov (United States)

    Singh, Rajat Kumar; Srivastava, Rajiv; Singh, Yatindra Nath

    In this article, we present the comparative analysis of various optical packet switch architectures. The comparison is done on the basis of bursty traffic arrival and the optical cost of various optical components used to build that switch. The architectures chosen for the analysis were previously proposed by us and their performance was evaluated only for the uniform random traffic arrival. Hence, this article can be considered as the cumulative and effective extension of the previous works. The computer simulations are performed to obtain the packet loss probability and average delay in presence of bursty traffic.

  4. Optical Packet Switching Demostrator

    DEFF Research Database (Denmark)

    Mortensen, Brian Bach; Berger, Michael Stübert

    2002-01-01

    In the IST project DAVID (data and voice integration over DWDM) work is carried out defining possible architectures of future optical packet switched networks. The feasibility of the architecture is to be verified in a demonstration set-up. This article describes the demonstrator set-up and the m......In the IST project DAVID (data and voice integration over DWDM) work is carried out defining possible architectures of future optical packet switched networks. The feasibility of the architecture is to be verified in a demonstration set-up. This article describes the demonstrator set...

  5. VAX Professional Workstation goes graphic

    Energy Technology Data Exchange (ETDEWEB)

    Downward, J.G.

    1984-01-01

    The VAX Professional Workstation (VPW) is a collection of programs and procedures designed to provide an integrated work-station environment for the staff at KMS Fusion's research laboratories. During the past year numerous capabilities have been added to VPW, including support for VT125/VT240/4014 graphic workstations, editing windows, and additional desk utilities. Graphics workstation support allows users to create, edit, and modify graph data files, enter the data via a graphic tablet, create simple plots with DATATRIEVE or DECgraph on ReGIS terminals, or elaborate plots with TEKGRAPH on ReGIS or Tektronix terminals. Users may assign display error bars to the data and interactively plot it in a variety of ways. Users also can create and display viewgraphs. Hard copy output for a large network of office terminals is obtained by multiplexing each terminal's video output into a recently developed video multiplexer front ending a single channel video hard copy unit.

  6. Multiwavelet packets and frame packets of L2( d)

    Indian Academy of Sciences (India)

    Springer Verlag Heidelberg #4 2048 1996 Dec 15 10:16:45

    ized to this setting. Further, we show how to construct various orthonormal bases of. L2( d) from the multiwavelet packets. Keywords. Wavelet; wavelet packets; frame packets; dilation matrix. 1. Introduction. Consider an orthonormal wavelet of L2( ). At the jth resolution level, the orthonormal basis {ψjk : j,k ∈ } generated by ...

  7. An improved packet structure

    KAUST Repository

    Bader, Ahmed

    2014-05-22

    A multihop network transmits a packet including a RACH area and a hop number. The RACH area includes a list of subcarriers. A source node in the network dynamically determines the size of the RACH area. A node in the network performs an open-loop transmit power control.

  8. An open architecture for medical image workstation

    Science.gov (United States)

    Liang, Liang; Hu, Zhiqiang; Wang, Xiangyun

    2005-04-01

    Dealing with the difficulties of integrating various medical image viewing and processing technologies with a variety of clinical and departmental information systems and, in the meantime, overcoming the performance constraints in transferring and processing large-scale and ever-increasing image data in healthcare enterprise, we design and implement a flexible, usable and high-performance architecture for medical image workstations. This architecture is not developed for radiology only, but for any workstations in any application environments that may need medical image retrieving, viewing, and post-processing. This architecture contains an infrastructure named Memory PACS and different kinds of image applications built on it. The Memory PACS is in charge of image data caching, pre-fetching and management. It provides image applications with a high speed image data access and a very reliable DICOM network I/O. In dealing with the image applications, we use dynamic component technology to separate the performance-constrained modules from the flexibility-constrained modules so that different image viewing or processing technologies can be developed and maintained independently. We also develop a weakly coupled collaboration service, through which these image applications can communicate with each other or with third party applications. We applied this architecture in developing our product line and it works well. In our clinical sites, this architecture is applied not only in Radiology Department, but also in Ultrasonic, Surgery, Clinics, and Consultation Center. Giving that each concerned department has its particular requirements and business routines along with the facts that they all have different image processing technologies and image display devices, our workstations are still able to maintain high performance and high usability.

  9. Early evaluation of MDIS workstations at Madigan Army Medical Center

    Science.gov (United States)

    Leckie, Robert G.; Goeringer, Fred; Smith, Donald V.; Bender, Gregory N.; Choi, Hyung-Sik; Haynor, David R.; Kim, Yongmin

    1993-06-01

    The image viewing workstation is an all-important link in the PACS (Picture Archiving and Communications System) chain since it represents the interface between the system and the user. For PACS to function, the working environment and transfer of information to the user must be the same or better than the traditional film-based system. The important characteristics of a workstation from a clinical standpoint are acceptable image quality, rapid response time, a friendly user interface, and a well-integrated, highly-reliable, fault-tolerant system which provides the user ample functions to complete his tasks successfully. Since early 1992, the MDIS (Medical Diagnostic Imaging Support) system's diagnostic and clinical workstations have been installed at Madigan Army Medical Center. Various functionalities and performance characteristics of the MDIS workstations such as image display, response time, database, and ergonomics will be presented. User comments and early experience with the workstations as well as new functionality recommended for the future will be discussed.

  10. Java Mission Evaluation Workstation System

    Science.gov (United States)

    Pettinger, Ross; Watlington, Tim; Ryley, Richard; Harbour, Jeff

    2006-01-01

    The Java Mission Evaluation Workstation System (JMEWS) is a collection of applications designed to retrieve, display, and analyze both real-time and recorded telemetry data. This software is currently being used by both the Space Shuttle Program (SSP) and the International Space Station (ISS) program. JMEWS was written in the Java programming language to satisfy the requirement of platform independence. An object-oriented design was used to satisfy additional requirements and to make the software easily extendable. By virtue of its platform independence, JMEWS can be used on the UNIX workstations in the Mission Control Center (MCC) and on office computers. JMEWS includes an interactive editor that allows users to easily develop displays that meet their specific needs. The displays can be developed and modified while viewing data. By simply selecting a data source, the user can view real-time, recorded, or test data.

  11. Design requirements for radiology workstations.

    Science.gov (United States)

    Moise, Adrian; Atkins, M Stella

    2004-06-01

    This article stresses the importance of capturing feedback from representative users in the early stages of product development. We present our solution to producing quality requirement specifications for radiology workstations, specifications that remain valid over time because we successfully anticipated the industry trends and the user's needs. We present the results from a user study performed in December 1999 in a radiology clinic equipped with state-of-the-art Picture Archiving and Communications Systems (PACS) and imaging scanners. The study involved eight radiologists who answered questions and provided comments on three complementary research topics. First, we asked our subjects to enumerate the advantages and the disadvantages for both softcopy and hardcopy reading. We identified the two major factors for productivity improvement through the use of PACS workstations: workflow re-engineering and process automation. Second, we collected radiologist feedback on the use of hanging protocols (HPs). The results indicated the high importance of automatic image organization through HPs, with the potential effect of reducing the interpretation time by 10-20%. Our subjects estimated that 10-15 HPs would cover about 85%-95% of the regular radiological examinations. Third, we investigated the impact of the display devices on the radiologist's workflow. Our results indicated that the number and the properties of the monitors is a modality-specific requirement. The main results from this study on key functional requirements for softcopy interpretation only recently were incorporated in most of the current, successful PACS workstations.

  12. Anthropology: Smithsonian Institution Teacher's Resource Packet.

    Science.gov (United States)

    National Museum of Natural History, Washington, DC.

    This teacher's research guide for the National Museum of Natural History (Smithsonian Institution) is designed for junior and senior high school teachers to integrate anthropology into their social studies and science classes. The information in this packet consists of a list of books for teachers and students, classroom activities, and other…

  13. Wireless Avionics Packet to Support Fault Tolerance for Flight Applications

    Science.gov (United States)

    Block, Gary L.; Whitaker, William D.; Dillon, James W.; Lux, James P.; Ahmad, Mohammad

    2009-01-01

    In this protocol and packet format, data traffic is monitored by all network interfaces to determine the health of transmitter and subsystems. When failures are detected, the network inter face applies its recover y policies to provide continued service despite the presence of faults. The protocol, packet format, and inter face are independent of the data link technology used. The current demonstration system supports both commercial off-the-shelf wireless connections and wired Ethernet connections. Other technologies such as 1553 or serial data links can be used for the network backbone. The Wireless Avionics packet is divided into three parts: a header, a data payload, and a checksum. The header has the following components: magic number, version, quality of service, time to live, sending transceiver, function code, payload length, source Application Data Interface (ADI) address, destination ADI address, sending node address, target node address, and a sequence number. The magic number is used to identify WAV packets, and allows the packet format to be updated in the future. The quality of service field allows routing decisions to be made based on this value and can be used to route critical management data over a dedicated channel. The time to live value is used to discard misrouted packets while the source transceiver is updated at each hop. This information is used to monitor the health of each transceiver in the network. To identify the packet type, the function code is used. Besides having a regular data packet, the system supports diagnostic packets for fault detection and isolation. The payload length specifies the number of data bytes in the payload, and this supports variable-length packets in the network. The source ADI is the address of the originating interface. This can be used by the destination application to identify the originating source of the packet where the address consists of a subnet, subsystem class within the subnet, a subsystem unit

  14. Application development environment for advanced digital workstations

    Science.gov (United States)

    Valentino, Daniel J.; Harreld, Michael R.; Liu, Brent J.; Brown, Matthew S.; Huang, Lu J.

    1998-06-01

    One remaining barrier to the clinical acceptance of electronic imaging and information systems is the difficulty in providing intuitive access to the information needed for a specific clinical task (such as reaching a diagnosis or tracking clinical progress). The purpose of this research was to create a development environment that enables the design and implementation of advanced digital imaging workstations. We used formal data and process modeling to identify the diagnostic and quantitative data that radiologists use and the tasks that they typically perform to make clinical decisions. We studied a diverse range of radiology applications, including diagnostic neuroradiology in an academic medical center, pediatric radiology in a children's hospital, screening mammography in a breast cancer center, and thoracic radiology consultation for an oncology clinic. We used object- oriented analysis to develop software toolkits that enable a programmer to rapidly implement applications that closely match clinical tasks. The toolkits support browsing patient information, integrating patient images and reports, manipulating images, and making quantitative measurements on images. Collectively, we refer to these toolkits as the UCLA Digital ViewBox toolkit (ViewBox/Tk). We used the ViewBox/Tk to rapidly prototype and develop a number of diverse medical imaging applications. Our task-based toolkit approach enabled rapid and iterative prototyping of workstations that matched clinical tasks. The toolkit functionality and performance provided a 'hands-on' feeling for manipulating images, and for accessing textual information and reports. The toolkits directly support a new concept for protocol based-reading of diagnostic studies. The design supports the implementation of network-based application services (e.g., prefetching, workflow management, and post-processing) that will facilitate the development of future clinical applications.

  15. Multiwavelet packets and frame packets of L2 (d)

    Indian Academy of Sciences (India)

    Home; Journals; Proceedings – Mathematical Sciences; Volume 111; Issue 4. Multiwavelet Packets ... To overcome this disadvantage Coifman, Meyer, and Wickerhauser constructed wavelet packets. We extend this ... Department of Mathematics, Indian Institute of Technology, Kanpur 208 016, India; Stat.-Math. Unit, Indian ...

  16. A prototype integrated medical workstation environment

    NARCIS (Netherlands)

    E.M. van Mulligen (Erik); T. Timmers (Teun); F. van den Heuvel (F.); J.H. van Bemmel (Jan)

    1993-01-01

    markdownabstractAbstract In this paper the requirements, design, and implementation of a prototype integrated medical workstation environment are outlined. The aim of the workstation is to provide user-friendly, task-oriented support for clinicians, based on existing software and data. The

  17. Mars Science Laboratory Workstation Test Set

    Science.gov (United States)

    Henriquez, David A.; Canham, Timothy K.; Chang, Johnny T.; Villaume, Nathaniel

    2009-01-01

    The Mars Science Laboratory developed the Workstation TestSet (WSTS) is a computer program that enables flight software development on virtual MSL avionics. The WSTS is the non-real-time flight avionics simulator that is designed to be completely software-based and run on a workstation class Linux PC.

  18. Active workstations to fight sedentary behaviour.

    Science.gov (United States)

    Torbeyns, Tine; Bailey, Stephen; Bos, Inge; Meeusen, Romain

    2014-09-01

    The impact of active workstations has been studied in several settings, and several outcomes have been investigated. However, the effects on health, work performance, quality of life, etc., have never been systematically reviewed. To evaluate the existing literature about active workstations and their possible positive health and work performance effects. We searched the electronic databases PubMed and Web of Science (up until 28 February 2014). The search terms we used were 'active workstation', 'standing workstation', 'standing desk', 'stand up workstation', 'stand up desk', 'walking desk', 'walking workstation', 'treadmill workstation', 'treadmill desk', 'cycling workstation', 'cycling desk' and 'bike desk', in combination with 'health', 'quality of life', 'cognition', 'computer task performance', 'absenteeism', 'productivity', 'academic achievement', 'cognitive decline', and 'independent living'. In addition, we searched the reference lists of relevant published articles. Randomized controlled trials, non-randomized controlled trials and non-randomized non-controlled trials investigating the introduction of active workstations in humans were included in this systematic review. Only original studies were included, and we did not accept studies combining the introduction of active workstations with other interventions. Outcomes concerning health, energy expenditure, cognition, quality of life and work performance were included. We included 32 studies, of which five were longitudinal studies in school-aged children, 10 were longitudinal studies in adults and 17 were non-longitudinal studies in adults. Sixteen studies investigated standing desks, 15 investigated walking desks, and one investigated a cycling workstation. The general findings were decreased sitting time, increased energy expenditure, a positive effect on several health markers, no detrimental effect on work performance, no acute effect on cognitive function and no straightforward findings concerning

  19. Optical packet switched networks

    DEFF Research Database (Denmark)

    Hansen, Peter Bukhave

    1999-01-01

    range that covers the EDFA window and conversion speeds of 20 Gbit/s and 40 Gbit/s are presented. Furthermore, the regenerative capability due to a nonlinear transfer function is verified at 20 Gbit/s. Following, the transmission characteristics of the IWC is analysed. The chirp measurements indicate...... in interferometric wavelength converters is investigated showing that a 10 Gbit/s 19 4x4 swich blocks can be cascaded at a BER of 10-14. An analytical traffic model enables the calculation of the traffice performance of a WDM packet network. Hereby the importance of WDM and wavelegth conversion in the switch blocks...... that there is a difference in the transmission properties for co- and counter propagation conversion, which is supported by transmission experiments. The combined use of SOA gates and interferometric wavelength converters illustrates the regenerative capability of the IWCs at 2.5, 10 and 20 Gbit/s by increasing the input...

  20. Orbiter Flying Qualities (OFQ) Workstation user's guide

    Science.gov (United States)

    Myers, Thomas T.; Parseghian, Zareh; Hogue, Jeffrey R.

    1988-01-01

    This project was devoted to the development of a software package, called the Orbiter Flying Qualities (OFQ) Workstation, for working with the OFQ Archives which are specially selected sets of space shuttle entry flight data relevant to flight control and flying qualities. The basic approach to creation of the workstation software was to federate and extend commercial software products to create a low cost package that operates on personal computers. Provision was made to link the workstation to large computers, but the OFQ Archive files were also converted to personal computer diskettes and can be stored on workstation hard disk drives. The primary element of the workstation developed in the project is the Interactive Data Handler (IDH) which allows the user to select data subsets from the archives and pass them to specialized analysis programs. The IDH was developed as an application in a relational database management system product. The specialized analysis programs linked to the workstation include a spreadsheet program, FREDA for spectral analysis, MFP for frequency domain system identification, and NIPIP for pilot-vehicle system parameter identification. The workstation also includes capability for ensemble analysis over groups of missions.

  1. Bohmian trajectories of Airy packets

    Energy Technology Data Exchange (ETDEWEB)

    Nassar, Antonio B., E-mail: anassar@hw.com [Science Department, Harvard-Westlake School, 3700 Coldwater Canyon, Studio City, 91604 (United States); Department of Sciences, University of California, Los Angeles, Extension Program, 10995 Le Conte Avenue, Los Angeles, CA 90024 (United States); Miret-Artés, Salvador [Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 123, 28006 Madrid (Spain)

    2014-09-15

    The discovery of Berry and Balazs in 1979 that the free-particle Schrödinger equation allows a non-dispersive and accelerating Airy-packet solution has taken the folklore of quantum mechanics by surprise. Over the years, this intriguing class of wave packets has sparked enormous theoretical and experimental activities in related areas of optics and atom physics. Within the Bohmian mechanics framework, we present new features of Airy wave packet solutions to Schrödinger equation with time-dependent quadratic potentials. In particular, we provide some insights to the problem by calculating the corresponding Bohmian trajectories. It is shown that by using general space–time transformations, these trajectories can display a unique variety of cases depending upon the initial position of the individual particle in the Airy wave packet. Further, we report here a myriad of nontrivial Bohmian trajectories associated to the Airy wave packet. These new features are worth introducing to the subject’s theoretical folklore in light of the fact that the evolution of a quantum mechanical Airy wave packet governed by the Schrödinger equation is analogous to the propagation of a finite energy Airy beam satisfying the paraxial equation. Numerous experimental configurations of optics and atom physics have shown that the dynamics of Airy beams depends significantly on initial parameters and configurations of the experimental set-up.

  2. A Next Generation BioPhotonics Workstation

    DEFF Research Database (Denmark)

    Glückstad, Jesper; Palima, Darwin; Tauro, Sandeep

    2011-01-01

    We are developing a Next Generation BioPhotonics Workstation to be applied in research on regulated microbial cell growth including their underlying physiological mechanisms, in vivo characterization of cell constituents and manufacturing of nanostructures and meta-materials.......We are developing a Next Generation BioPhotonics Workstation to be applied in research on regulated microbial cell growth including their underlying physiological mechanisms, in vivo characterization of cell constituents and manufacturing of nanostructures and meta-materials....

  3. Conversion of the Aeronautics Interactive Workstation

    Science.gov (United States)

    Riveras, Nykkita L.

    2004-01-01

    This summer I am working in the Educational Programs Office. My task is to convert the Aeronautics Interactive Workstation from a Macintosh (Mac) platform to a Personal Computer (PC) platform. The Aeronautics Interactive Workstation is a workstation in the Aerospace Educational Laboratory (AEL), which is one of the three components of the Science, Engineering, Mathematics, and Aerospace Academy (SEMAA). The AEL is a state-of-the-art, electronically enhanced, computerized classroom that puts cutting-edge technology at the fingertips of participating students. It provides a unique learning experience regarding aerospace technology that features activities equipped with aerospace hardware and software that model real-world challenges. The Aeronautics Interactive Workstation, in particular, offers a variety of activities pertaining to the history of aeronautics. When the Aeronautics Interactive Workstation was first implemented into the AEL it was designed with Macromedia Director 4 for a Mac. Today it is being converted to Macromedia DirectorMX2004 for a PC. Macromedia Director is the proven multimedia tool for building rich content and applications for CDs, DVDs, kiosks, and the Internet. It handles the widest variety of media and offers powerful features for building rich content that delivers red results, integrating interactive audio, video, bitmaps, vectors, text, fonts, and more. Macromedia Director currently offers two programmingkripting languages: Lingo, which is Director's own programmingkripting language and JavaScript. In the workstation, Lingo is used in the programming/scripting since it was the only language in use when the workstation was created. Since the workstation was created with an older version of Macromedia Director it hosted significantly different programming/scripting protocols. In order to successfully accomplish my task, the final product required correction of Xtra and programming/scripting errors. I also had to convert the Mac platform

  4. Next Generation BioPhotonics Workstation

    DEFF Research Database (Denmark)

    Glückstad, Jesper

    2010-01-01

    We are developing a Next Generation BioPhotonics Workstation to be applied in research on regulated microbial cell growth including their underlying physiological mechanisms, in vivo characterization of cell constituents and manufacturing of nanostructures and meta-materials.......We are developing a Next Generation BioPhotonics Workstation to be applied in research on regulated microbial cell growth including their underlying physiological mechanisms, in vivo characterization of cell constituents and manufacturing of nanostructures and meta-materials....

  5. The network management expert system prototype for Sun Workstations

    Science.gov (United States)

    Leigh, Albert

    1990-01-01

    Networking has become one of the fastest growing areas in the computer industry. The emergence of distributed workstations make networking more popular because they need to have connectivity between themselves as well as with other computer systems to share information and system resources. Making the networks more efficient and expandable by selecting network services and devices that fit to one's need is vital to achieve reliability and fast throughput. Networks are dynamically changing and growing at a rate that outpaces the available human resources. Therefore, there is a need to multiply the expertise rapidly rather than employing more network managers. In addition, setting up and maintaining networks by following the manuals can be tedious and cumbersome even for an experienced network manager. This prototype expert system was developed to experiment on Sun Workstations to assist system and network managers in selecting and configurating network services.

  6. Ergonomic Evaluations of Microgravity Workstations

    Science.gov (United States)

    Whitmore, Mihriban; Berman, Andrea H.; Byerly, Diane

    1996-01-01

    Various gloveboxes (GBXs) have been used aboard the Shuttle and ISS. Though the overall technical specifications are similar, each GBX's crew interface is unique. JSC conducted a series of ergonomic evaluations of the various glovebox designs to identify human factors requirements for new designs to provide operator commonality across different designs. We conducted 2 0g evaluations aboard the Shuttle to evaluate the material sciences GBX and the General Purpose Workstation (GPWS), and a KC-135 evaluation to compare combinations of arm hole interfaces and foot restraints (flexible arm holes were better than rigid ports for repetitive fine manipulation tasks). Posture analysis revealed that the smallest and tallest subjects assumed similar postures at all four configurations, suggesting that problematic postures are not necessarily a function of the operator s height but a function of the task characteristics. There was concern that the subjects were using the restrictive nature of the GBX s cuffs as an upper-body restraint to achieve such high forces, which might lead to neck/shoulder discomfort. EMG data revealed more consistent muscle performance at the GBX; the variability in the EMG profiles observed at the GPWS was attributed to the subjects attempts to provide more stabilization for themselves in the loose, flexible gauntlets. Tests revealed that the GBX should be designed for a 95 percentile American male to accommodate a neutral working posture. In addition, the foot restraint with knee support appeared beneficial for GBX operations. Crew comments were to provide 2 foot restraint mechanical modes, loose and lock-down, to accommodate a wide range of tasks without egressing the restraint system. Thus far, we have developed preliminary design guidelines for GBXs and foot.

  7. Implementation of a Data Packet Generator Using Pattern Matching for Wearable ECG Monitoring Systems

    Directory of Open Access Journals (Sweden)

    Yun Hong Noh

    2014-07-01

    Full Text Available In this paper, a packet generator using a pattern matching algorithm for real-time abnormal heartbeat detection is proposed. The packet generator creates a very small data packet which conveys sufficient crucial information for health condition analysis. The data packet envelopes real time ECG signals and transmits them to a smartphone via Bluetooth. An Android application was developed specifically to decode the packet and extract ECG information for health condition analysis. Several graphical presentations are displayed and shown on the smartphone. We evaluate the performance of abnormal heartbeat detection accuracy using the MIT/BIH Arrhythmia Database and real time experiments. The experimental result confirm our finding that abnormal heart beat detection is practically possible. We also performed data compression ratio and signal restoration performance evaluations to establish the usefulness of the proposed packet generator and the results were excellent.

  8. Entropy Based Detection of DDoS Attacks in Packet Switching Network Models

    Science.gov (United States)

    Lawniczak, Anna T.; Wu, Hao; di Stefano, Bruno

    Distributed denial-of-service (DDoS) attacks are network-wide attacks that cannot be detected or stopped easily. They affect “natural” spatio-temporal packet traffic patterns, i.e. “natural distributions” of packets passing through the routers. Thus, they affect “natural” information entropy profiles, a sort of “fingerprints”, of normal packet traffic. We study if by monitoring information entropy of packet traffic through selected routers one may detect DDoS attacks or anomalous packet traffic in packet switching network (PSN) models. Our simulations show that the considered DDoS attacks of “ping” type cause shifts in information entropy profiles of packet traffic monitored even at small sets of routers and that it is easier to detect these shifts if static routing is used instead of dynamic routing. Thus, network-wide monitoring of information entropy of packet traffic at properly selected routers may provide means for detecting DDoS attacks and other anomalous packet traffics.

  9. Design of a fluorescence-lifetime imaging microscope workstation

    Science.gov (United States)

    Boddeke, Frank R.; van Geest, Lambertus K.; Young, Ian T.

    1997-05-01

    One of the promising recent developments in fluorescence microscopy is fluorescence lifetime imaging microscopy. This type of microscopy images the lifetime of fluorescence molecules (in the nano second range) rather than the amount of light emitted by these molecules. This physical property is of interest while it gives information about the local environment of the molecule, such as molecular concentration of O2, Ca2+, pH, and conjugation. Our goal is to design a affordable, robust and easy-to-use FLIM workstation which is completely automated and does not need any difficult calibration. Therefore we are developing a workstation which applies a homodyne detection scheme (frequency range: 1 - 100 MHz) with use of an intensity modulated laser-diode (635 nm) and a gain modulated intensified CCD camera to image fluorescence lifetimes in the range of 1 - 100 ns. Using these components it is possible to make a FLIM workstation based on a normal fluorescence microscope by just replacing the light source and image detector. The FLIM image acquisition procedure in software allows automatic optical measurements of fluorescence lifetimes in different ranges and mixtures of lifetimes by adjusting the modulation frequency.

  10. Multifunction Habitat Workstation/OLED Development

    Science.gov (United States)

    Schumacher, Shawn; Salazar, George; Schmidt, Oron

    2013-01-01

    This paper gives a general outline of both a multifunction habitat workstation and the research put into an Organic Light Emitting Diode (OLED) device. It first covers the tests that the OLED device will go through to become flight ready along with reasoning. Guidelines for building an apparatus to house the display and its components are given next, with the build of such following. The three tests the OLED goes through are presented (EMI, Thermal/Vac, Radiation) along with the data recovered. The second project of a multifunction workstation is then discussed in the same pattern. Reasoning for building such a workstation with telepresence in mind is offered. Build guidelines are presented first, with the build timeline following. Building the workstation will then be shown in great detail along with accompanying photos. Once the workstation has been discussed, the versatility of its functions are given. The paper concludes with future views and concepts that can added when the time or technology presents itself.

  11. Multifractality of quantum wave packets

    Energy Technology Data Exchange (ETDEWEB)

    Martin, John [Institut de Physique Nucleaire, Atomique et de Spectroscopie, Universite de Liege, Bat. B15, B - 4000 Liege (Belgium); Garcia-Mata, Ignacio [Instituto de Investigaciones Fisicas de Mar del Plata, CONICET-UNMdP, Funes 3350, B7602AYL Mar del Plata (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnologicas, Buenos Aires (Argentina); Giraud, Olivier [LPTMS, CNRS and Universite Paris-Sud, UMR 8626, Bat. 100, 91405 Orsay (France); Georgeot, Bertrand [Universite de Toulouse, UPS, Laboratoire de Physique Theorique (IRSAMC), F-31062 Toulouse (France); CNRS, LPT (IRSAMC), F-31062 Toulouse (France)

    2013-07-01

    We study the multifractality of individual wave packets in a periodically kicked system through a combination of numerical and analytical works. We consider a version of the mathematical Ruijsenaars-Schneider model and reinterpreted it physically in order to describe the spreading with time of quantum wave packets in a system where multifractality can be tuned by varying a parameter. We compare different methods to measure the multifractality of wave packets and identify the best one. We find the multifractality to decrease with time until it reaches an asymptotic limit, which is different from the multifractality of eigenvectors but related to it, as is the rate of the decrease. Our results could guide the study of experimental situations where multifractality is present in quantum systems.

  12. Energy Level Performance of Packet Delivery Schemes in Wireless Sensor Networks in Shadowed Channel

    Directory of Open Access Journals (Sweden)

    Arnab NANDI

    2010-07-01

    Full Text Available This paper evaluates energy level performance of three packet delivery schemes in a Wireless Sensor Networks (WSN in shadowed channel. Three different information delivery mechanisms are investigated using regenerative relays with or without error correction capability. Energy consumption for successful delivery of a data packet for each mechanism is evaluated and compared under several conditions of node density, bit rate, transmit power etc. Energy efficiency of different retransmission schemes is evaluated. Further an optimal packet length based on energy efficiency is derived. Impact of different level of severity of shadowing on energy consumption is also investigated. Further impact of fixed and optimal packet size on energy consumption is analyzed.

  13. Optimizing the pathology workstation "cockpit": Challenges and solutions

    Directory of Open Access Journals (Sweden)

    Elizabeth A Krupinski

    2010-01-01

    Full Text Available The 21 st century has brought numerous changes to the clinical reading (i.e., image or virtual pathology slide interpretation environment of pathologists and it will continue to change even more dramatically as information and communication technologies (ICTs become more widespread in the integrated healthcare enterprise. The extent to which these changes impact the practicing pathologist differ as a function of the technology under consideration, but digital "virtual slides" and the viewing of images on computer monitors instead of glass slides through a microscope clearly represents a significant change in the way that pathologists extract information from these images and render diagnostic decisions. One of the major challenges facing pathologists in this new era is how to best optimize the pathology workstation, the reading environment and the new and varied types of information available in order to ensure efficient and accurate processing of this information. Although workstations can be stand-alone units with images imported via external storage devices, this scenario is becoming less common as pathology departments connect to information highways within their hospitals and to external sites. Picture Archiving and Communications systems are no longer confined to radiology departments but are serving the entire integrated healthcare enterprise, including pathology. In radiology, the workstation is often referred to as the "cockpit" with a "digital dashboard" and the reading room as the "control room." Although pathology has yet to "go digital" to the extent that radiology has, lessons derived from radiology reading "cockpits" can be quite valuable in setting up the digital pathology reading room. In this article, we describe the concept of the digital dashboard and provide some recent examples of informatics-based applications that have been shown to improve the workflow and quality in digital reading environments.

  14. Real-Time Mesoscale Prediction on workstations.

    Science.gov (United States)

    Cotton, William R.; Thompson, Gregory; Mieike, Paul W., Jr.

    1994-03-01

    Experience in performing real-time mesoscale numerical prediction forecasts using the Regional Atmospheric Modeling System (RAMS) over Colorado for a winter season on high-performance workstations is summarized. Performance evaluation is done for specific case studies and, statistically, for the entire winter season. RAMS forecasts are also compared with nested grid model forecasts. In addition, RAMS precipitation forecasts with a simple "dump bucket" scheme are compared with explicit, bulk microphysics parameterization schemes. The potential applications and political/ social problems of having a readily accessible, real-time mesoscale forecasting capability on low-cost, high-performance workstations is discussed.

  15. Downlink Transmission of Short Packets

    DEFF Research Database (Denmark)

    Trillingsgaard, Kasper Fløe; Popovski, Petar

    2017-01-01

    the principles of frame design and show the impact of the new design in scenarios that feature short data packets, which are central to various 5G and Internet of Things applications. We~treat framing for downlink transmission in an AWGN broadcast channel with $K$ users, where the sizes of the messages...

  16. Recycling Study Guide [Resource Packet].

    Science.gov (United States)

    Wisconsin State Dept. of Natural Resources, Madison.

    This resource packet contains six documents developed by the Wisconsin Department of Natural Resources in order to help teachers infuse the environmental education topics of recycling and solid waste into social studies, art, English, health, mathematics, science, and environmental education classes. "Recycling Study Guide" contains 19…

  17. The Uses of Reading and Study Skills: Individualized Inservice Packet Number IX. Teaching Teen Reading Series.

    Science.gov (United States)

    Eberhart, Nancy A.; Lloyd, Margaret V.

    Consisting of nine individualized inservice packets, the Teaching Teen Reading Series describes reading procedures applicable to instruction in all subjects in the elementary, middle, and secondary school. This ninth packet is designed to enable the teacher to help students read for information and pleasure and includes sections discussing ways to…

  18. Reduction in Power Consumption of Packet Counter on VIRTEX-6 FPGA by Frequency Scaling

    DEFF Research Database (Denmark)

    Pandey, Nisha; Pandey, Bishwajeet; Hussain, Dil muhammed Akbar

    2017-01-01

    In Today’s World it is very easy to share the information fast may be within seconds or even may be less. However, the required data is shared so it is the main concern. We share data over web and data is transferred in the form of packets. How these data packets are transmitted is all concept...

  19. Ripples in Communication : Reconfigurable and Adaptive Wireless Communication Systems based on Wavelet Packet Modulators

    NARCIS (Netherlands)

    Lakshmanan, M.K.

    2011-01-01

    Wavelet Packet Modulation (WPM) is a multi-carrier transmission technique that uses orthogonal wavelet packet bases to combine a collection of information bits into a single composite signal. This system can be considered as a viable alternative, for wide-band communication, to the popular

  20. Estimation of Frame Independent and Enhancement Components for Speech Communication over Packet Networks

    DEFF Research Database (Denmark)

    Giacobello, Daniele; Murthi, Manohar N.; Christensen, Mads Græsbøll

    2010-01-01

    In this paper, we describe a new approach to cope with packet loss in speech coders. The idea is to split the information present in each speech packet into two components, one to independently decode the given speech frame and one to enhance it by exploiting interframe dependencies. The scheme i...

  1. Toward Massive, Ultrareliable, and Low-Latency Wireless Communication With Short Packets

    DEFF Research Database (Denmark)

    Durisi, Giuseppe; Koch, Tobias; Popovski, Petar

    2016-01-01

    Most of the recent advances in the design of high-speed wireless systems are based on information-theoretic principles that demonstrate how to efficiently transmit long data packets. However, the upcoming wireless systems, notably the fifth-generation (5G) system, will need to support novel traffic...... types that use short packets. For example, short packets represent the most common form of traffic generated by sensors and other devices involved in machine-to-machine (M2M) communications. Furthermore, there are emerging applications in which small packets are expected to carry critical information...... that should be received with low latency and ultrahigh reliability. Current wireless systems are not designed to support short-packet transmissions. For example, the design of current systems relies on the assumption that the metadata (control information) is of negligible size compared to the actual...

  2. Next Genertation BioPhotonics Workstation

    DEFF Research Database (Denmark)

    Bañas, Andrew Rafael; Palima, Darwin; Tauro, Sandeep

    We will outline the specs of our Biophotonics Workstation that can generate up to 100 reconfigurable laser-traps making 3D real-time optical manipulation of advanced structures, cells or tiny particles possible with the use of joysticks or gaming devices. Optically actuated nanoneedles may...

  3. Introduction of a virtual workstation into radiology medical student education.

    Science.gov (United States)

    Strickland, Colin D; Lowry, Peter A; Petersen, Brian D; Jesse, Mary K

    2015-03-01

    OBJECTIVE. This article describes the creation of a virtual workstation for use by medical students and implementation of that workstation in the reading room. CONCLUSION. A radiology virtual workstation for medical students was created using OsiriX imaging software to authentically simulate the experience of interacting with cases selected to cover important musculoskeletal imaging diagnoses. A workstation that allows the manipulation and interpretation of complete anonymized DICOM images may enhance the educational experience of medical students.

  4. Let's Use Cognitive Science to Create Collaborative Workstations.

    Science.gov (United States)

    Reicher, Murray A; Wolfe, Jeremy M

    2016-05-01

    When informed by an understanding of cognitive science, radiologists' workstations could become collaborative to improve radiologists' performance and job satisfaction. The authors review relevant literature and present several promising areas of research, including image toggling, eye tracking, cognitive computing, intelligently restricted messaging, work habit tracking, and innovative input devices. The authors call for more research in "perceptual design," a promising field that can complement advances in computer-aided detection. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

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

    2004-01-01

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

  6. [Troubleshooting for Carestream GC1.5 Workstation].

    Science.gov (United States)

    Yu, Liangning; Zhang, Junjie; Yang, Zhicheng

    2015-11-01

    This paper is maintenance of four kinds of failures of Carestream GC1.5 the workstation used several years to summarize, workstation software, change the host, burn, workstations transmission, and four kinds of failures of the specific case of itemized elimination steps are introduced.

  7. The role of the mainframe terminated : mainframe versus workstation

    CERN Document Server

    Williams, D O

    1991-01-01

    I. What mainframes? - The surgeon-general has determined that you shall treat all costs with care ( continental effects, discounts assumed, next month's or last month's prices, optimism of the reporter. II. Typical mainframe hardware III. Typical mainframe software IV. What workstations? VI. Typical workstation hardware VII. Typical workstation software VIII. Titan vs PDP-7s XIX.Historic answer X. Amdahl's Law....

  8. IP Traceback through modified Probabilistic Packet Marking algorithm using Chinese Remainder Theorem

    Directory of Open Access Journals (Sweden)

    Y. Bhavani

    2015-06-01

    Full Text Available Probabilistic Packet Marking algorithm suggests a methodology to identify all the participated routers of the attack path by probabilistically marking the packets. In this approach, these marked packets contain partial information regarding the routers of the attack path. At receiver, to get the complete information of every router, it requires more number of marked packets and hence more combinations and more false positives. To overcome this drawback we have presented a novel idea in finding the exact IP address of the routers in the attack path by applying Chinese Remainder Theorem. The result of our implementation reveals that our idea requires less number of marked packets and takes no time in constructing the attack path. The same idea is true even in the case of multiple attackers.

  9. Marine and Coastal Resources. Global Issues Education Packet.

    Science.gov (United States)

    Holm, Amy E.

    At least 70% of the Earth is covered with water. This packet provides background information on eight areas of concern regarding marine and coastal resources. Considered are: (1) "Coastal Resources"; (2) "Mangroves"; (3) "Coral Reefs"; (4) "Ocean Resources"; (5) "Aquaculture"; (6) "Pollution"; (7) "Marine Debris"; and (8) "The Global Commons."…

  10. Comparison of Deep Packet Inspection (DPI) Tools for Traffic Classification

    DEFF Research Database (Denmark)

    Bujlow, Tomasz; Carela-Español, Valentín; Barlet-Ros, Pere

    the researchers do not only have the full payloads, but also they are provided the information which application created the flow. Therefore, the dataset is useful for testing Deep Packet Inspection (DPI) tools, as well as statistical, and port-based classifiers. The dataset was created in a fully manual way...

  11. Network Architecture of a Packet-switched WDM

    NARCIS (Netherlands)

    Dey, D.; Koonen, A.M.J.; Salvador, M.R.

    2000-01-01

    We propose a packet-switched WDM slotted ring network with destination release. The total bandwidth of each channel is divided into a fixed number of equal-sized slots. The nodes are equipped with fixed transmitters and tunable receivers. Control information, which is transmitted on a specific

  12. The image-interpretation-workstation of the future: lessons learned

    Science.gov (United States)

    Maier, S.; van de Camp, F.; Hafermann, J.; Wagner, B.; Peinsipp-Byma, E.; Beyerer, J.

    2017-05-01

    In recent years, professionally used workstations got increasingly complex and multi-monitor systems are more and more common. Novel interaction techniques like gesture recognition were developed but used mostly for entertainment and gaming purposes. These human computer interfaces are not yet widely used in professional environments where they could greatly improve the user experience. To approach this problem, we combined existing tools in our imageinterpretation-workstation of the future, a multi-monitor workplace comprised of four screens. Each screen is dedicated to a special task in the image interpreting process: a geo-information system to geo-reference the images and provide a spatial reference for the user, an interactive recognition support tool, an annotation tool and a reporting tool. To further support the complex task of image interpreting, self-developed interaction systems for head-pose estimation and hand tracking were used in addition to more common technologies like touchscreens, face identification and speech recognition. A set of experiments were conducted to evaluate the usability of the different interaction systems. Two typical extensive tasks of image interpreting were devised and approved by military personal. They were then tested with a current setup of an image interpreting workstation using only keyboard and mouse against our image-interpretationworkstation of the future. To get a more detailed look at the usefulness of the interaction techniques in a multi-monitorsetup, the hand tracking, head pose estimation and the face recognition were further evaluated using tests inspired by everyday tasks. The results of the evaluation and the discussion are presented in this paper.

  13. Integrated Design of a Telerobotic Workstation

    Science.gov (United States)

    Rochlis, Jennifer L.; Clarke, John-Paul

    2001-01-01

    The experiments described in this paper are part of a larger joint MIT/NASA research effort that focuses on the development of a methodology for designing and evaluating integrated interfaces for highly dexterous and multi-functional telerobots. Specifically, a telerobotic workstation is being designed for an Extravehicular Activity (EVA) anthropomorphic space station telerobot. Previous researchers have designed telerobotic workstations based upon performance of discrete subsets of tasks (for example, peg-in-hole, tracking, etc.) without regard for transitions that operators go through between tasks performed sequentially in the context of larger integrated tasks. The exploratory research experiments presented here took an integrated approach and assessed how subjects operating a full-immersion telerobot perform during the transitions between sub-tasks of two common EVA tasks. Preliminary results show that up to 30% of total task time is spent gaining and maintaining Situation Awareness (SA) of their task space and environment during transitions. Although task performance improves over the two trial days, the percentage of time spent on SA remains the same. This method identifies areas where workstation displays and feedback mechanisms are most needed to increase operator performance and decrease operator workload - areas that previous research methods have not been able to address.

  14. Multiwavelet packet entropy and its application in transmission line fault recognition and classification.

    Science.gov (United States)

    Liu, Zhigang; Han, Zhiwei; Zhang, Yang; Zhang, Qiaoge

    2014-11-01

    Multiwavelets possess better properties than traditional wavelets. Multiwavelet packet transformation has more high-frequency information. Spectral entropy can be applied as an analysis index to the complexity or uncertainty of a signal. This paper tries to define four multiwavelet packet entropies to extract the features of different transmission line faults, and uses a radial basis function (RBF) neural network to recognize and classify 10 fault types of power transmission lines. First, the preprocessing and postprocessing problems of multiwavelets are presented. Shannon entropy and Tsallis entropy are introduced, and their difference is discussed. Second, multiwavelet packet energy entropy, time entropy, Shannon singular entropy, and Tsallis singular entropy are defined as the feature extraction methods of transmission line fault signals. Third, the plan of transmission line fault recognition using multiwavelet packet entropies and an RBF neural network is proposed. Finally, the experimental results show that the plan with the four multiwavelet packet energy entropies defined in this paper achieves better performance in fault recognition. The performance with SA4 (symmetric antisymmetric) multiwavelet packet Tsallis singular entropy is the best among the combinations of different multiwavelet packets and the four multiwavelet packet entropies.

  15. A Practical Terrestrial Packet Radio Network.

    Science.gov (United States)

    1983-11-01

    large city teleports the need for efficient distribution of satellite down- links (and uplinks) has become more pressing. RAPAC or Radio Packet...rep- resents a proposed RAPAC based DTS system that was sub- mitted by the Xerox Corporation. A central broadcasting site, in an allocated...service networks. The RAPAC form of DTS (also Cable Packet Communications System, CAPAC) is a packet radio strategy which uses microwave antennas

  16. Generalization of Posture Training to Computer Workstations in an Applied Setting

    Science.gov (United States)

    Sigurdsson, Sigurdur O.; Ring, Brandon M.; Needham, Mick; Boscoe, James H.; Silverman, Kenneth

    2011-01-01

    Improving employees' posture may decrease the risk of musculoskeletal disorders. The current paper is a systematic replication and extension of Sigurdsson and Austin (2008), who found that an intervention consisting of information, real-time feedback, and self-monitoring improved participant posture at mock workstations. In the current study,…

  17. Development and Use of a GIS Workstation at the Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Dickey, Mark W [ORNL

    2007-01-01

    Oak Ridge National Laboratory (ORNL) is the Department of Energy s (DOE) largest multipurpose science and energy laboratory. As an interdisciplinary research organization, access to information plays a critical part in the success of the many research efforts in progress at the Laboratory. The Research Library, in a supportive role, enables staff to fulfill the Laboratory s mission by making available a myriad of information resources including paper and electronic maps. The Research Library Geographic Information System (GIS) workstation was developed to better serve library customers by providing convenient access to a variety of mapping resources. The GIS workstation functions as a supplement to the paper map collection by providing customers with maps in an electronic format that can easily be inserted into memos, reports, and journal articles. Customer interest, together with the growing availability of low-cost and user-friendly mapping software, led to the development of the GIS workstation, which hosts an array of commercial mapping software that enables customers to produce ready-made topographic maps, current and historical maps, and road maps. Customers may also create customized maps using their own data or data supplied by the software vendor. This article focuses on the development, implementation, and use of the library s GIS workstation by providing a brief description of hardware components, mapping resources, and how these resources are used by Laboratory staff.

  18. Computerized Workstation for Tsunami Hazard Monitoring

    Science.gov (United States)

    Lavrentiev-Jr, Mikhail; Marchuk, Andrey; Romanenko, Alexey; Simonov, Konstantin; Titov, Vasiliy

    2010-05-01

    We present general structure and functionality of the proposed Computerized Workstation for Tsunami Hazard Monitoring (CWTHM). The tool allows interactive monitoring of hazard, tsunami risk assessment, and mitigation - at all stages, from the period of strong tsunamigenic earthquake preparation to inundation of the defended coastal areas. CWTHM is a software-hardware complex with a set of software applications, optimized to achieve best performance on hardware platforms in use. The complex is calibrated for selected tsunami source zone(s) and coastal zone(s) to be defended. The number of zones (both source and coastal) is determined, or restricted, by available hardware resources. The presented complex performs monitoring of selected tsunami source zone via the Internet. The authors developed original algorithms, which enable detection of the preparation zone of the strong underwater earthquake automatically. For the so-determined zone the event time, magnitude and spatial location of tsunami source are evaluated by means of energy of the seismic precursors (foreshocks) analysis. All the above parameters are updated after each foreshock. Once preparing event is detected, several scenarios are forecasted for wave amplitude parameters as well as the inundation zone. Estimations include the lowest and the highest wave amplitudes and the least and the most inundation zone. In addition to that, the most probable case is calculated. In case of multiple defended coastal zones, forecasts and estimates can be done in parallel. Each time the simulated model wave reaches deep ocean buoys or tidal gauge, expected values of wave parameters and inundation zones are updated with historical events information and pre-calculated scenarios. The Method of Splitting Tsunami (MOST) software package is used for mathematical simulation. The authors suggest code acceleration for deep water wave propagation. As a result, performance is 15 times faster compared to MOST, original version

  19. Angular momentum transport with twisted exciton wave packets

    Science.gov (United States)

    Zang, Xiaoning; Lusk, Mark T.

    2017-10-01

    A chain of cofacial molecules with CN or CN h symmetry supports excitonic states with a screwlike structure. These can be quantified with the combination of an axial wave number and an azimuthal winding number. Combinations of these states can be used to construct excitonic wave packets that spiral down the chain with well-determined linear and angular momenta. These twisted exciton wave packets can be created and annihilated using laser pulses, and their angular momentum can be optically modified during transit. This allows for the creation of optoexcitonic circuits in which information, encoded in the angular momentum of light, is converted into excitonic wave packets that can be manipulated, transported, and then reemitted. A tight-binding paradigm is used to demonstrate the key ideas. The approach is then extended to quantify the evolution of twisted exciton wave packets in a many-body, multilevel time-domain density functional theory setting. In both settings, numerical methods are developed that allow the site-to-site transfer of angular momentum to be quantified.

  20. Workstation Designs for a Cis-Lunar Deep Space Habitat

    Science.gov (United States)

    Howe, A. Scott

    2014-01-01

    Using the International Standard Payload Rack (ISPR) system, a suite of workstations required for deep space missions have been proposed to fill out habitation functions in an International Space Station (ISS) derived Cis-lunar Deep Space Habitat. This paper introduces the functional layout of the Cis-lunar habitat design, and describes conceptual designs for modular deployable work surfaces, General Maintenance Workstation (GMWS), In-Space Manufacturing Workstation (ISMW), Intra-Vehicular Activity Telerobotics Work Station (IVA-TRWS), and Galley / Wardroom.

  1. Telerobotics Workstation (TRWS) for Deep Space Habitats

    Science.gov (United States)

    Mittman, David S.; Howe, Alan S.; Tores, Recaredo J.; Rochlis, Jennifer L.; Hambuchen, Kimberly A.; Demel, Matthew; Chapman, Christopher C.

    2012-01-01

    On medium- to long-duration human spaceflight missions, latency in communications from Earth could reduce efficiency or hinder local operations, control, and monitoring of the various mission vehicles and other elements. Regardless of the degree of autonomy of any one particular element, a means of monitoring and controlling the elements in real time based on mission needs would increase efficiency and response times for their operation. Since human crews would be present locally, a local means for monitoring and controlling all the various mission elements is needed, particularly for robotic elements where response to interesting scientific features in the environment might need near- instantaneous manipulation and control. One of the elements proposed for medium- and long-duration human spaceflight missions, the Deep Space Habitat (DSH), is intended to be used as a remote residence and working volume for human crews. The proposed solution for local monitoring and control would be to provide a workstation within the DSH where local crews can operate local vehicles and robotic elements with little to no latency. The Telerobotics Workstation (TRWS) is a multi-display computer workstation mounted in a dedicated location within the DSH that can be adjusted for a variety of configurations as required. From an Intra-Vehicular Activity (IVA) location, the TRWS uses the Robot Application Programming Interface Delegate (RAPID) control environment through the local network to remotely monitor and control vehicles and robotic assets located outside the pressurized volume in the immediate vicinity or at low-latency distances from the habitat. The multiple display area of the TRWS allows the crew to have numerous windows open with live video feeds, control windows, and data browsers, as well as local monitoring and control of the DSH and associated systems.

  2. Efficient Parallel Engineering Computing on Linux Workstations

    Science.gov (United States)

    Lou, John Z.

    2010-01-01

    A C software module has been developed that creates lightweight processes (LWPs) dynamically to achieve parallel computing performance in a variety of engineering simulation and analysis applications to support NASA and DoD project tasks. The required interface between the module and the application it supports is simple, minimal and almost completely transparent to the user applications, and it can achieve nearly ideal computing speed-up on multi-CPU engineering workstations of all operating system platforms. The module can be integrated into an existing application (C, C++, Fortran and others) either as part of a compiled module or as a dynamically linked library (DLL).

  3. Habitat Demonstration Unit Medical Operations Workstation Upgrades

    Science.gov (United States)

    Trageser, Katherine H.

    2011-01-01

    This paper provides an overview of the design and fabrication associated with upgrades for the Medical Operations Workstation in the Habitat Demonstration Unit. The work spanned a ten week period. The upgrades will be used during the 2011 Desert Research and Technology Studies (Desert RATS) field campaign. Upgrades include a deployable privacy curtain system, a deployable tray table, an easily accessible biological waste container, reorganization and labeling of the medical supplies, and installation of a retractable camera. All of the items were completed within the ten week period.

  4. Effective Packet Number for 5G IM WeChat Application at Early Stage Traffic Classification

    Directory of Open Access Journals (Sweden)

    Muhammad Shafiq

    2017-01-01

    Full Text Available Accurate network traffic classification at early stage is very important for 5G network applications. During the last few years, researchers endeavored hard to propose effective machine learning model for classification of Internet traffic applications at early stage with few packets. Nevertheless, this essential problem still needs to be studied profoundly to find out effective packet number as well as effective machine learning (ML model. In this paper, we tried to solve the above-mentioned problem. For this purpose, five Internet traffic datasets are utilized. Initially, we extract packet size of 20 packets and then mutual information analysis is carried out to find out the mutual information of each packet on n flow type. Thereafter, we execute 10 well-known machine learning algorithms using crossover classification method. Two statistical analysis tests, Friedman and Wilcoxon pairwise tests, are applied for the experimental results. Moreover, we also apply the statistical tests for classifiers to find out effective ML classifier. Our experimental results show that 13–19 packets are the effective packet numbers for 5G IM WeChat application at early stage network traffic classification. We also find out effective ML classifier, where Random Forest ML classifier is effective classifier at early stage Internet traffic classification.

  5. Pictorial warnings on cigarette packets: Effectiveness and ...

    African Journals Online (AJOL)

    Placing pictorial warning messages of potential health hazards of tobacco smoking on cigarette packets is mandatory by law in Egypt. Photos of victims of heavy tobacco smoking are placed on the front and back covers of cigarette packets in an attempt to warn both users and would be users of the health risks associated ...

  6. Packetisation in Optical Packet Switch Fabrics using adaptive timeout values

    DEFF Research Database (Denmark)

    Mortensen, Brian Bach

    2006-01-01

    Hybrid electro-optical packet switches utilize optics in the backplane to switch optical packets from inputs to outputs on electronic line cards. The optical packets are traditionally considerably larger than minimum size IP packets. IP packets entering the switch must be formatted (segmented...... delay and throughput in hybrid electro-optical packet switching. Furthermore, it is investigated how large a speedup is required in order to provide 100% throughput....

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

    Science.gov (United States)

    Wang, Chunliang; Ritter, Felix; Smedby, Orjan

    2010-07-01

    To enhance the functional expandability of a picture archiving and communication systems (PACS) workstation and to facilitate the integration of third-part image-processing modules, we propose a browser-server style method. In the proposed solution, the PACS workstation shows the front-end user interface defined in an XML file while the image processing software is running in the background as a server. Inter-process communication (IPC) techniques allow an efficient exchange of image data, parameters, and user input between the PACS workstation and stand-alone image-processing software. Using a predefined communication protocol, the PACS workstation developer or image processing software developer does not need detailed information about the other system, but will still be able to achieve seamless integration between the two systems and the IPC procedure is totally transparent to the final user. A browser-server style solution was built between OsiriX (PACS workstation software) and MeVisLab (Image-Processing Software). Ten example image-processing modules were easily added to OsiriX by converting existing MeVisLab image processing networks. Image data transfer using shared memory added processing time while the other IPC methods cost 1-5 s in our experiments. The browser-server style communication based on IPC techniques is an appealing method that allows PACS workstation developers and image processing software developers to cooperate while focusing on different interests.

  8. Wave packet systems on local fields

    Science.gov (United States)

    Shah, Firdous A.; Ahmad, Owais

    2017-10-01

    In this paper, we introduce the notion of wave packet systems on local fields of positive characteristic and derive some characterizations of these systems by means of two basic equations in the Fourier domain. More precisely, we establish a complete characterization of orthogonal wave packet systems in L2(K) which include the corresponding results of wavelet analysis and Gabor theory as the special cases. We shall also provide a sufficient condition of the completeness of wave packet systems on local fields of positive characteristic subject to some mild conditions. The paper concludes with the necessary and sufficient conditions for the wave packet systems to be wave packet Parseval frames for L2(K) .

  9. DPDK-based Improvement of Packet Forwarding

    Directory of Open Access Journals (Sweden)

    Bi Hao

    2016-01-01

    Full Text Available Reel-time processing of packets occupies a significant position in the field of computer network security. With theexplosive growth of the backbone link rate,which is consistent with Gilder's law, many bottlenecks of server performance leave the real-time data stream unprocessed.Thus, we proposedto take use of DPDK(Data Plan Development Kit framework to achieve an intelligent NIC packet forwarding system. During this research, we deeply analysis the forwarding process of packet in DPDK and improve its DMA mode.According to the results of experiment, the system greatly enhanced the performance of packet forwarding,and the throughput of forwarding 64-byet or random-length packets by 20Gbit NIC reaches13.3Gbps and 18.7Gbps(dual ports forwarding.

  10. Kinematic analysis of post office employees' workstations.

    Science.gov (United States)

    Draicchio, Francesco; Silvetti, Alessio; Forzano, Federico; Iavicoli, Sergio; Ranavolo, Alberto

    2012-01-01

    This study analyzed a post office clerk's tasks, comparing two workstation models. The clerk was facing the client in one, and seated at 45 degrees to the counter in the other. We analyzed the most frequent tasks and those presenting the most critical points: 1) payment of a postal order; 2) accepting a registered letter, breaking them down into subtasks. We used an optoelectronic system for kinematic analysis, and calculated the range of motion of the trunk and arms in the three spatial planes. The 45( position required less torsion of the trunk and head when using the printer, placed to the left of the employee. A larger worktop improved the workstation, leaving more room for equipment and allowing the worker to sit frontally to the monitor. However, this solution involved a shorter distance between the worker and the client with longer extension of the shoulder and elbow and less trunk flexion. These findings suggested a modification in the layout that shortens the distance between the worker and client.

  11. Earthbound applications for NASA's physician workstation

    Science.gov (United States)

    Grams, R.; Yu, F. S.; Li, B.; Iddings, E.; Fiorentino, R.; Shao, S.; Wang, L.; Broughton, H.

    1993-01-01

    The dream of a space probe to Mars or an astronaut colony on the moon persists. Despite years of setbacks and delays, NASA continues to lay the foundation for a new frontier in space. The necessity of a self contained health maintenance facility is an integral part of this stellar venture. As a subsystem of this health maintenance facility, the physician or astronaut workstation was envisioned as the vehicle of interface between the computer resources of the space station and the care provider. Our efforts to define and build this interface have resulted in a series of programs which can now be tested and refined using earth-based applications. The modules which have dual-use application from the NASA workstation include: patient scheduling and master patient index, pharmacy, laboratory, medical library, problem list/progress notes, and digital medical records. Our current plan is to develop these tools as objects that can be assembled in a variety of configurations. This will allow the technology to be used by the private sector where each doctor can select the starting point of his outpatient office system and add modules as he makes progress in system integration and training.

  12. Novel scheme for efficient and cost-effective forwarding of packets in optical networks without header modification

    DEFF Research Database (Denmark)

    Wessing, Henrik; Fjelde, Tina; Christiansen, Henrik Lehrmann

    2001-01-01

    We present a novel scheme for addressing the outputs in optical packet switches and demonstrate its good scalability. The scheme requires neither header modification nor distribution of routing information to the packet switches, thus reducing optical component count while simplifying network...

  13. Modelling of Energy Expenditure at Welding Workstations: Effect of ...

    African Journals Online (AJOL)

    The welding workstation usually generates intense heat during operations, which may affect the welder's health if not properly controlled, and can also affect the performance of the welder at work. Consequently, effort to control the conditions of the welding workstation is essential, and is therefore pursued in this paper.

  14. Developing our Next Generation BioPhotonics Workstation

    DEFF Research Database (Denmark)

    Bañas, Andrew Rafael; Palima, Darwin; Tauro, Sandeep

    2011-01-01

    limit the trapping range because of high numerical aperture and imaging requirements. To circumvent these issues, we are developing a BioPhotonics Workstation platform that supports extension modules through a long working distance geometry. Furthermore, a long range axial manipulation range is achieved...... manipulation undertakings. We present ongoing research activities for constructing a compact next generation BioPhotonics Workstation....

  15. ANL statement of site strategy for computing workstations

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, K.R. (ed.); Boxberger, L.M.; Amiot, L.W.; Bretscher, M.E.; Engert, D.E.; Moszur, F.M.; Mueller, C.J.; O' Brien, D.E.; Schlesselman, C.G.; Troyer, L.J.

    1991-11-01

    This Statement of Site Strategy describes the procedure at Argonne National Laboratory for defining, acquiring, using, and evaluating scientific and office workstations and related equipment and software in accord with DOE Order 1360.1A (5-30-85), and Laboratory policy. It is Laboratory policy to promote the installation and use of computing workstations to improve productivity and communications for both programmatic and support personnel, to ensure that computing workstations acquisitions meet the expressed need in a cost-effective manner, and to ensure that acquisitions of computing workstations are in accord with Laboratory and DOE policies. The overall computing site strategy at ANL is to develop a hierarchy of integrated computing system resources to address the current and future computing needs of the laboratory. The major system components of this hierarchical strategy are: Supercomputers, Parallel computers, Centralized general purpose computers, Distributed multipurpose minicomputers, and Computing workstations and office automation support systems. Computing workstations include personal computers, scientific and engineering workstations, computer terminals, microcomputers, word processing and office automation electronic workstations, and associated software and peripheral devices costing less than $25,000 per item.

  16. Post-deployment usability evaluation of a radiology workstation

    NARCIS (Netherlands)

    Jorritsma, Wiard; Cnossen, Fokie; Dierckx, Rudi A.; Oudkerk, Matthijs; Van Ooijen, Peter M. A.

    Objectives: To determine the number, nature and severity of usability issues radiologists encounter while using a commercially available radiology workstation in clinical practice, and to assess how well the results of a pre-deployment usability evaluation of this workstation generalize to clinical

  17. Imaging workstations for computer-aided primatology: promises and pitfalls.

    Science.gov (United States)

    Vannier, M W; Conroy, G C

    1989-01-01

    In this paper, the application of biomedical imaging workstations to primatology will be explained and evaluated. The technological basis, computer hardware and software aspects, and the various uses of several types of workstations will all be discussed. The types of workstations include: (1) Simple - these display-only workstations, which function as electronic light boxes, have applications as terminals to picture archiving and communication (PAC) systems. (2) Diagnostic reporting - image-processing workstations that include the ability to perform straightforward manipulations of gray scale and raw data values will be considered for operations such as histogram equalization (whether adaptive or global), gradient edge finders, contour generation, and region of interest, as well as other related functions. (3) Manipulation systems - three-dimensional modeling and computer graphics with application to radiation therapy treatment planning, and surgical planning and evaluation will be considered. A technology of prime importance in the function of these workstations lies in communications and networking. The hierarchical organization of an electronic computer network and workstation environment with the interrelationship of simple, diagnostic reporting, and manipulation workstations to a coaxial or fiber optic network will be analyzed.

  18. Commodity clusters: Performance comparison between PC`s and workstations

    Energy Technology Data Exchange (ETDEWEB)

    Carter, R.; Laroco, J.; Armstrong, R.

    1996-03-01

    Workstation clusters were originally developed as a way to leverage the better cost basis of UNIX workstations to perform computations previously handled only by relatively more expensive supercomputers. Commodity workstation clusters take this evolutionary process one step further by replacing equivalent proprietary workstation functionality with less expensive PC technology. As PC technology encroaches on proprietary UNIX workstation vendor markets, these vendors will see a declining share of the overall market. As technology advances continue, the ability to upgrade a workstations performance plays a large role in cost analysis. For example, a major upgrade to a typical UNIX workstation means replacing the whole machine. As major revisions to the UNIX vendor`s product line come out, brand new systems are introduced. IBM compatibles, however, are modular by design, and nothing need to be replaced except the components that are truly improved. The DAISy cluster, for example, is about to undergo a major upgrade from 90MHz Pentiums to 200MHz Pentium Pros. All of the memory -- the system`s largest expense -- and disks, power supply, etc., can be reused. As a result, commodity workstation clusters ought to gain an increasingly large share of the distributed computing market.

  19. Engineering and manipulating exciton wave packets

    Science.gov (United States)

    Zang, Xiaoning; Montangero, Simone; Carr, Lincoln D.; Lusk, Mark T.

    2017-05-01

    When a semiconductor absorbs light, the resulting electron-hole superposition amounts to a uncontrolled quantum ripple that eventually degenerates into diffusion. If the conformation of these excitonic superpositions could be engineered, though, they would constitute a new means of transporting information and energy. We show that properly designed laser pulses can be used to create such excitonic wave packets. They can be formed with a prescribed speed, direction, and spectral make-up that allows them to be selectively passed, rejected, or even dissociated using superlattices. Their coherence also provides a handle for manipulation using active, external controls. Energy and information can be conveniently processed and subsequently removed at a distant site by reversing the original procedure to produce a stimulated emission. The ability to create, manage, and remove structured excitons comprises the foundation for optoexcitonic circuits with application to a wide range of quantum information, energy, and light-flow technologies. The paradigm is demonstrated using both tight-binding and time-domain density functional theory simulations.

  20. Packet Guide to Routing and Switching

    CERN Document Server

    Hartpence, Bruce

    2011-01-01

    Go beyond layer 2 broadcast domains with this in-depth tour of advanced link and internetwork layer protocols, and learn how they enable you to expand to larger topologies. An ideal follow-up to Packet Guide to Core Network Protocols, this concise guide dissects several of these protocols to explain their structure and operation. This isn't a book on packet theory. Author Bruce Hartpence built topologies in a lab as he wrote this guide, and each chapter includes several packet captures. You'll learn about protocol classification, static vs. dynamic topologies, and reasons for installing a pa

  1. Wavelength conversion in optical packet switching

    DEFF Research Database (Denmark)

    Danielsen, Søren Lykke; Hansen, Peter Bukhave; Stubkjær, Kristian

    1998-01-01

    A detailed traffic analysis of optical packet switch design is performed. Special consideration is given to the complexity of the optical buffering and the overall switch block structure is considered in general. Wavelength converters are shown to improve the traffic performance of the switch...... blocks for both random and bursty traffic. Furthermore, the traffic performance of switch blocks with add-drop switches has been assessed in a Shufflenetwork showing the advantage of having converters at the inlets. Finally, the aspect of synchronization is discussed through a proposal to operate...... the packet switch block asynchronously, i.e. without packet alignment at the input...

  2. Q FUNCTION AWARE OPTICAL PACKET SWITCH WITH LOW PACKET LOSS RATE

    Directory of Open Access Journals (Sweden)

    OMPAL SINGH

    2017-03-01

    Full Text Available Optical packet switching (OPS is a very promising technology for the next generation data transfer due to the very large bandwidth of the optical fiber. The success of the OPS relies heavily on design of the node architecture which supports comparatively larger buffering capacity without detiorating signal quality too much and it should provide very low packet loss probability with reasonably low average delay. In this paper, a design analysis of low complexity OPS node architecture is discussed along-with its advantages. The presented architecture support both fixed and variable length packets. The packets are stored in a single piece of fiber using the WDM technology. Physical layer analysis presented in this paper is to obtain the Q function (Bit Error Rate. Finally, the Monte Carlo simulation is done to obtain the packet loss. The average delay performance of the switch and effect of Q values on packet loss rates are discussed.

  3. Survey of ANL organization plans for word processors, personal computers, workstations, and associated software. Revision 3

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, K.R.

    1991-11-01

    The Computing and Telecommunications Division (CTD) has compiled this Survey of ANL Organization Plans for Word Processors, Personal Computers, Workstations, and Associated Software to provide DOE and Argonne with a record of recent growth in the acquisition and use of personal computers, microcomputers, and word processors at ANL. Laboratory planners, service providers, and people involved in office automation may find the Survey useful. It is for internal use only, and any unauthorized use is prohibited. Readers of the Survey should use it as a reference that documents the plans of each organization for office automation, identifies appropriate planners and other contact people in those organizations, and encourages the sharing of this information among those people making plans for organizations and decisions about office automation. The Survey supplements information in both the ANL Statement of Site Strategy for Computing Workstations and the ANL Site Response for the DOE Information Technology Resources Long-Range Plan.

  4. Survey of ANL organization plans for word processors, personal computers, workstations, and associated software

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, K.R.

    1991-11-01

    The Computing and Telecommunications Division (CTD) has compiled this Survey of ANL Organization Plans for Word Processors, Personal Computers, Workstations, and Associated Software to provide DOE and Argonne with a record of recent growth in the acquisition and use of personal computers, microcomputers, and word processors at ANL. Laboratory planners, service providers, and people involved in office automation may find the Survey useful. It is for internal use only, and any unauthorized use is prohibited. Readers of the Survey should use it as a reference that documents the plans of each organization for office automation, identifies appropriate planners and other contact people in those organizations, and encourages the sharing of this information among those people making plans for organizations and decisions about office automation. The Survey supplements information in both the ANL Statement of Site Strategy for Computing Workstations and the ANL Site Response for the DOE Information Technology Resources Long-Range Plan.

  5. Sparsely-Packetized Predictive Control by Orthogonal Matching Pursuit

    DEFF Research Database (Denmark)

    Nagahara, Masaaki; Quevedo, Daniel; Østergaard, Jan

    2012-01-01

    We study packetized predictive control, known to be robust against packet dropouts in networked systems. To obtain sparse packets for rate-limited networks, we design control packets via an ℓ0 optimization, which can be eectively solved by orthogonal matching pursuit. Our formulation ensures...

  6. Future directions in packet radio architectures and protocols

    Science.gov (United States)

    Shacham, Nachum; Westcott, Jil

    1987-01-01

    The technology of packet switching over multihop, multiple-access channels has evolved to the point at which its protocols can now support internetwork operation of medium-size networks whose nodes possess some degree of mobility. As regards the needs and challenges of the future operating environment, it is clear that these can be met only by enhancing the packet radio architecture and its protocols. Several enhancements that allow the organization of large, dynamic networks that can operate over multiple channels, adapt to varying conditions, and possess self-monitoring and self-control capabilities are discussed. As these areas are examined, the attendant issues and tradeoffs are discussed; in addition, some protocols and information regarding their performance are presented.

  7. Satcom access in the evolved packet core

    NARCIS (Netherlands)

    Cano, M.D.; Norp, A.H.J.; Popova, M.P.

    2012-01-01

    Satellite communications (Satcom) networks are increasingly integrating with terrestrial communications networks, namely Next Generation Networks (NGN). In the area of NGN the Evolved Packet Core (EPC) is a new network architecture that can support multiple access technologies. When Satcom is

  8. Dispersionless wave packets in Dirac materials

    Energy Technology Data Exchange (ETDEWEB)

    Jakubský, Vít, E-mail: jakub@ujf.cas.cz [Department of Theoretical Physics, Nuclear Physics Institute, 25068 Řež (Czech Republic); Tušek, Matěj, E-mail: tusekmat@fjfi.cvut.cz [Department of Mathematics, Czech Technical University in Prague, Trojanova 13, 120 00 Prague (Czech Republic)

    2017-03-15

    We show that a wide class of quantum systems with translational invariance can host dispersionless, soliton-like, wave packets. We focus on the setting where the effective, two-dimensional Hamiltonian acquires the form of the Dirac operator. The proposed framework for construction of the dispersionless wave packets is illustrated on silicene-like systems with topologically nontrivial effective mass. Our analytical predictions are accompanied by a numerical analysis and possible experimental realizations are discussed.

  9. On the theory of wave packets

    Science.gov (United States)

    Naumov, D. V.

    2013-12-01

    In this paper we discuss some aspects of the theory of wave packets. We consider a popular noncovariant Gaussian model used in various applications and show that it predicts too slow a longitudinal dispersion rate for relativistic particles. We revise this approach by considering a covariant model of Gaussian wave packets, and examine our results by inspecting a wave packet of arbitrary form. A general formula for the time dependence of the dispersion of a wave packet of arbitrary form is found. Finally, we give a transparent interpretation of the disappearance of the wave function over time due to the dispersion—a feature often considered undesirable, but which is unavoidable for wave packets. We find, starting from simple examples, proceeding with their generalizations and finally by considering the continuity equation, that the integral over time of both the flux and probability densities are asymptotically proportional to the factor 1/| x|2 in the rest frame of the wave packet, just as in the case of an ensemble of classical particles.

  10. Development of a Pamphlet Targeting Computer Workstation Ergonomics

    Science.gov (United States)

    Faraci, Jennifer S.

    1997-01-01

    With the increased use of computers throughout Goddard Space Flight Center, the Industrial Hygiene Office (IHO) has observed a growing trend in the number of health complaints attributed to poor computer workstation setup. A majority of the complaints has centered around musculoskeletal symptoms, including numbness, pain, and tingling in the upper extremities, shoulders, and neck. Eye strain and headaches have also been reported. In some cases, these symptoms can lead to chronic conditions such as repetitive strain injuries (RSI's). In an effort to prevent or minimize the frequency of these symptoms among the GSFC population, the IHO conducts individual ergonomic workstation evaluations and ergonomics training classes upon request. Because of the extensive number of computer workstations at GSFC, and the limited amount of manpower which the Industrial Hygiene staff could reasonably allocate to conduct workstation evaluations and employee training, a pamphlet was developed with a two-fold purpose: (1) to educate the GSFC population about the importance of ergonomically-correct computer workstation setup and the potential effects of a poorly configured workstation; and (2) to enable employees to perform a general assessment of their own workstations and make any necessary modifications for proper setup.

  11. Comparison of Ring-Buffer-Based Packet Capture Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Barker, Steven Andrew [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2015-10-01

    Traditional packet-capture solutions using commodity hardware incur a large amount of overhead as packets are copied multiple times by the operating system. This overhead slows sensor systems to a point where they are unable to keep up with high bandwidth traffic, resulting in dropped packets. Incomplete packet capture files hinder network monitoring and incident response efforts. While costly commercial hardware exists to capture high bandwidth traffic, several software-based approaches exist to improve packet capture performance using commodity hardware.

  12. Post-deployment usability evaluation of a radiology workstation.

    Science.gov (United States)

    Jorritsma, Wiard; Cnossen, Fokie; Dierckx, Rudi A; Oudkerk, Matthijs; Van Ooijen, Peter M A

    2016-01-01

    To determine the number, nature and severity of usability issues radiologists encounter while using a commercially available radiology workstation in clinical practice, and to assess how well the results of a pre-deployment usability evaluation of this workstation generalize to clinical practice. The usability evaluation consisted of semi-structured interviews and observations of twelve users using the workstation during their daily work. Usability issues and positive usability findings were documented. Each issue was given a severity rating and its root cause was determined. Results were compared to the results of a pre-deployment usability evaluation of the same workstation. Ninety-two usability issues were identified, ranging from issues that cause minor frustration or delay, to issues that cause significant delays, prevent users from completing tasks, or even pose a potential threat to patient safety. The results of the pre-deployment usability evaluation had limited generalizability to clinical practice. This study showed that radiologists encountered a large number and a wide variety of usability issues when using a commercially available radiology workstation in clinical practice. This underlines the need for effective usability engineering in radiology. Given the limitations of pre-deployment usability evaluation in radiology, which were confirmed by our finding that the results of a pre-deployment usability evaluation of this workstation had limited generalizability to clinical practice, it is vital that radiology workstation vendors devote significant resources to usability engineering efforts before deployment of their workstation, and to continue these efforts after the workstation is deployed in a hospital. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Modelling Packet Departure Times using a Known PDF

    Directory of Open Access Journals (Sweden)

    Stanislav Klucik

    2014-01-01

    Full Text Available This paper deals with IPTV traffic source modelling and describes a packet generator based on a known probability density function which is measured and formed from a histogram. Histogram based probability density functions destroy an amount of information, because classes used to form the histogram often cover significantly more events than one. In this work, we propose an algorithm to generate far more output states of random variable X than the input probability distribution function is made from. In this generator is assumed that all IPTV packets of the same video stream are the same length. Therefore, only packet times are generated. These times are generated using the measured normalized histogram that is converted to a cumulative distribution function which acts as a finite number of states that can be addressed. To address these states we use an ON/OFF model that is driven by an uniform random number generator in (0, 1. When a state is chosen then the resulting value is equal to a histogram class. To raise the number of possible output states of the random variable X, we propose to use an uniform random number generator that generates numbers within the range of the chosen histogram class. This second uniform random number generator assures that the number of output states is far more larger than the number of histogram classes.

  14. Feasibility of Optical Packet Switched WDM Networks without Packet Synchronisation Under Bursty Traffic Conditions

    DEFF Research Database (Denmark)

    Fjelde, Tina; Hansen, Peter Bukhave; Kloch, Allan

    1999-01-01

    We show that complex packet synchronisation may be avoided in optical packetswitched networks. Detailed traffic analysis demonstrates that packet lossratios of 1e-10 are feasible under bursty traffic conditions for a highcapacity network consisting of asynchronously operated add-drop switch nodes...

  15. Flexible-rate optical packet generation/detection and label swapping for optical label switching networks

    Science.gov (United States)

    Wu, Zhongying; Li, Juhao; Tian, Yu; Ge, Dawei; Zhu, Paikun; Chen, Yuanxiang; Chen, Zhangyuan; He, Yongqi

    2017-03-01

    In recent years, optical label switching (OLS) gains lots of attentions due to its intrinsic advantages to implement protocol, bit-rate, granularity and data format transparency packet switching. In this paper, we propose a novel scheme to realize flexible-rate optical packet switching for OLS networks. At the transmitter node, flexible-rate packet is generated by parallel modulating different combinations of optical carriers generated from the optical multi-carrier generator (OMCG), among which the low-speed optical label occupies one carrier. At the switching node, label is extracted and re-generated in label processing unit (LPU). The payloads are switched based on routing information and new label is added after switching. At the receiver node, another OMCG serves as local oscillators (LOs) for optical payloads coherent detection. The proposed scheme offers good flexibility for dynamic optical packet switching by adjusting the payload bandwidth and could also effectively reduce the number of lasers, modulators and receivers for packet generation/detection. We present proof-of-concept demonstrations of flexible-rate packet generation/detection and label swapping in 12.5 GHz grid. The influence of crosstalk for cascaded label swapping is also investigated.

  16. On-board closed-loop congestion control for satellite based packet switching networks

    Science.gov (United States)

    Chu, Pong P.; Ivancic, William D.; Kim, Heechul

    1993-01-01

    NASA LeRC is currently investigating a satellite architecture that incorporates on-board packet switching capability. Because of the statistical nature of packet switching, arrival traffic may fluctuate and thus it is necessary to integrate congestion control mechanism as part of the on-board processing unit. This study focuses on the closed-loop reactive control. We investigate the impact of the long propagation delay on the performance and propose a scheme to overcome the problem. The scheme uses a global feedback signal to regulate the packet arrival rate of ground stations. In this scheme, the satellite continuously broadcasts the status of its output buffer and the ground stations respond by selectively discarding packets or by tagging the excessive packets as low-priority. The two schemes are evaluated by theoretical queuing analysis and simulation. The former is used to analyze the simplified model and to determine the basic trends and bounds, and the later is used to assess the performance of a more realistic system and to evaluate the effectiveness of more sophisticated control schemes. The results show that the long propagation delay makes the closed-loop congestion control less responsive. The broadcasted information can only be used to extract statistical information. The discarding scheme needs carefully-chosen status information and reduction function, and normally requires a significant amount of ground discarding to reduce the on-board packet loss probability. The tagging scheme is more effective since it tolerates more uncertainties and allows a larger margin of error in status information. It can protect the high-priority packets from excessive loss and fully utilize the downlink bandwidth at the same time.

  17. A versatile nondestructive evaluation imaging workstation

    Science.gov (United States)

    Chern, E. James; Butler, David W.

    1994-01-01

    Ultrasonic C-scan and eddy current imaging systems are of the pointwise type evaluation systems that rely on a mechanical scanner to physically maneuver a probe relative to the specimen point by point in order to acquire data and generate images. Since the ultrasonic C-scan and eddy current imaging systems are based on the same mechanical scanning mechanisms, the two systems can be combined using the same PC platform with a common mechanical manipulation subsystem and integrated data acquisition software. Based on this concept, we have developed an IBM PC-based combined ultrasonic C-scan and eddy current imaging system. The system is modularized and provides capacity for future hardware and software expansions. Advantages associated with the combined system are: (1) eliminated duplication of the computer and mechanical hardware, (2) unified data acquisition, processing and storage software, (3) reduced setup time for repetitious ultrasonic and eddy current scans, and (4) improved system efficiency. The concept can be adapted to many engineering systems by integrating related PC-based instruments into one multipurpose workstation such as dispensing, machining, packaging, sorting, and other industrial applications.

  18. Analysis of ocular surface area for comfortable VDT workstation layout.

    Science.gov (United States)

    Sotoyama, M; Jonai, H; Saito, S; Villanueva, M B

    1996-06-01

    This paper proposes a comfortable visual display terminal (VDT) workstation layout based on an analysis of ocular surface area (OSA). A large OSA induces eye irritation and eye fatigue because the eye surface is highly sensitive to various stimuli. The authors considered that OSA must be one of the useful indices of visual ergonomics and applied it to evaluate VDT workstation layout. Each subject was asked to perform a word processing task using four different VDT workstation layouts. It was found that the main factor affecting OSA was not cathode ray tube (CRT) height itself but the distance between the CRT and keyboard. Thus the following workstation layout is recommended to realize comfortable VDT operation: (1) the desk height should be adjusted to the user's height; and (2) the CRT display should be set closer to the keyboard to provide a smaller OSA.

  19. Motivating ergonomic computer workstation setup: sometimes training is not enough.

    Science.gov (United States)

    Sigurdsson, Sigurdur O; Artnak, Melissa; Needham, Mick; Wirth, Oliver; Silverman, Kenneth

    2012-01-01

    Musculoskeletal disorders lead to pain and suffering and result in high costs to industry. There is evidence to suggest that whereas conventional ergonomics training programs result in knowledge gains, they may not necessarily translate to changes in behavior. There were 11 participants in an ergonomics training program, and a subsample of participants received a motivational intervention in the form of incentives for correct workstation setup. Training did not yield any changes in ergonomics measures for any participant. Incentives resulted in marked and durable changes in targeted workstation measures. The data suggest that improving worker knowledge about ergonomically correct workstation setup does not necessarily lead to correct workstation setup, and that motivational interventions may be needed to achieve lasting behavior change.

  20. Application of the wavelet packet transform to vibration signals for surface roughness monitoring in CNC turning operations

    Science.gov (United States)

    García Plaza, E.; Núñez López, P. J.

    2018-01-01

    The wavelet packet transform method decomposes a time signal into several independent time-frequency signals called packets. This enables the temporary location of transient events occurring during the monitoring of the cutting processes, which is advantageous in monitoring condition and fault diagnosis. This paper proposes the monitoring of surface roughness using a single low cost sensor that is easily implemented in numerical control machine tools in order to make on-line decisions on workpiece surface finish quality. Packet feature extraction in vibration signals was applied to correlate the sensor signals to measured surface roughness. For the successful application of the WPT method, mother wavelets, packet decomposition level, and appropriate packet selection methods should be considered, but are poorly understood aspects in the literature. In this novel contribution, forty mother wavelets, optimal decomposition level, and packet reduction methods were analysed, as well as identifying the effective frequency range providing the best packet feature extraction for monitoring surface finish. The results show that mother wavelet biorthogonal 4.4 in decomposition level L3 with the fusion of the orthogonal vibration components (ax + ay + az) were the best option in the vibration signal and surface roughness correlation. The best packets were found in the medium-high frequency DDA (6250-9375 Hz) and high frequency ADA (9375-12500 Hz) ranges, and the feed acceleration component ay was the primary source of information. The packet reduction methods forfeited packets with relevant features to the signal, leading to poor results for the prediction of surface roughness. WPT is a robust vibration signal processing method for the monitoring of surface roughness using a single sensor without other information sources, satisfactory results were obtained in comparison to other processing methods with a low computational cost.

  1. ARQ with sequential decoding of packetized data - Queueing analysis

    Science.gov (United States)

    Shacham, N.

    1984-10-01

    The operation of a sequential decoder in a packet-switching environment is considered. Packets arrive randomly at the decoder, and a packet is stored in a buffer if the decoder is busy upon its arrival. The decoder devotes no more than a time-out period of predetermined length to the decoding of any single packet. If packet decoding is completed within that period, the packet leaves the system. Otherwise, it is retransmitted and its decoding starts anew. While a packet is retransmitted, the decoder decodes another packet that resides in its buffer. An upper bound on the maximum rate of packets that can be supported by the channel-decoder combination is derived, and the optimum time-out that maximizes that rate is determined. A discrete-time model of the decoder's queue is presented, and the average queue length and throughput are evaluated.

  2. Workstations studies and radiation protection; Etudes de postes et radioprotection

    Energy Technology Data Exchange (ETDEWEB)

    Lahaye, T. [Direction des relations du travail, 75 - Paris (France); Donadille, L.; Rehel, J.L.; Paquet, F. [Institut de Radioprotection et de Surete Nucleaire, 92 - Fontenay-aux-Roses (France); Beneli, C. [Paris-5 Univ., 75 (France); Cordoliani, Y.S. [Societe Francaise de Radioprotection, 92 - Fontenay-aux-Roses (France); Vrigneaud, J.M. [Assistance Publique - Hopitaux de Paris, 75 (France); Gauron, C. [Institut National de Recherche et de Securite, 75 - Paris (France); Petrequin, A.; Frison, D. [Association des Medecins du Travail des Salaries du Nucleaire (France); Jeannin, B. [Electricite de France (EDF), 75 - Paris (France); Charles, D. [Polinorsud (France); Carballeda, G. [cabinet Indigo Ergonomie, 33 - Merignac (France); Crouail, P. [Centre d' Etude sur l' Evaluation de la Protection dans le Domaine Nucleaire, 92 - Fontenay-aux-Roses (France); Valot, C. [IMASSA, 91 - Bretigny-sur-Orge (France)

    2006-07-01

    This day on the workstations studies for the workers follow-up, was organised by the research and health section. Devoted to the company doctors, for the competent persons in radiation protection, for the engineers of safety, it presented examples of methodologies and applications in the medical, industrial domain and the research, so contributing to a better understanding and an application of regulatory measures. The analysis of the workstation has to allow a reduction of the exposures and the risks and lead to the optimization of the medical follow-up. The agenda of this day included the different subjects as follow: evolution of the regulation in matter of demarcation of the regulated zones where the measures of workers protection are strengthened; presentation of the I.R.S.N. guide of help to the realization of a workstation study; implementation of a workstation study: case of radiology; the workstation studies in the research area; Is it necessary to impose the operational dosimetry in the services of radiodiagnostic? The experience feedback of a competent person in radiation protection (P.C.R.) in a hospital environment; radiation protection: elaboration of a good practices guide in medical field; the activities file in nuclear power plant: an evaluation tool of risks for the prevention. Methodological presentation and examples; insulated workstation study; the experience feedback of a provider; Contribution of the ergonomics to the determiners characterization in the ionizing radiation exposure situations;The workstations studies for the internal contamination in the fuel cycle facilities and the consideration of the results in the medical follow-up; R.E.L.I.R. necessity of workstation studies; the consideration of the human factor. (N.C.)

  3. C.A.D. and ergonomic workstations conception

    Science.gov (United States)

    Keravel, Francine

    1986-07-01

    Computer Aided Design is able to perform workstation's conception. An ergonomic data could be complete this view and warrant a coherent fiability conception. Complexe form representation machines, anthropometric data and environment factors are allowed to perceive the limit points between humain and new technology situation. Work ability users, safety, confort and human efficiency could be also included. Such a programm with expert system integration will give a complete listing appreciation about workstation's conception.

  4. Fair packet scheduling in Wireless Mesh Networks

    KAUST Repository

    Nawab, Faisal

    2014-02-01

    In this paper we study the interactions of TCP and IEEE 802.11 MAC in Wireless Mesh Networks (WMNs). We use a Markov chain to capture the behavior of TCP sessions, particularly the impact on network throughput due to the effect of queue utilization and packet relaying. A closed form solution is derived to numerically determine the throughput. Based on the developed model, we propose a distributed MAC protocol called Timestamp-ordered MAC (TMAC), aiming to alleviate the unfairness problem in WMNs. TMAC extends CSMA/CA by scheduling data packets based on their age. Prior to transmitting a data packet, a transmitter broadcasts a request control message appended with a timestamp to a selected list of neighbors. It can proceed with the transmission only if it receives a sufficient number of grant control messages from these neighbors. A grant message indicates that the associated data packet has the lowest timestamp of all the packets pending transmission at the local transmit queue. We demonstrate that a loose ordering of timestamps among neighboring nodes is sufficient for enforcing local fairness, subsequently leading to flow rate fairness in a multi-hop WMN. We show that TMAC can be implemented using the control frames in IEEE 802.11, and thus can be easily integrated in existing 802.11-based WMNs. Our simulation results show that TMAC achieves excellent resource allocation fairness while maintaining over 90% of maximum link capacity across a large number of topologies.

  5. An overview of high-speed networking for workstations

    Energy Technology Data Exchange (ETDEWEB)

    Hake, K.

    1995-04-01

    The telecommunications industry provides new technologies for GIS (Geographic Information System) workstation upgrades: Fast Ethernet, 100VG-AnyLAN, and Asynchronous Transfer Mode (ATM). These network technologies are based on approved standards and have industry backing (alliance for Fast Ethernet). This paper briefly examines these technologies. Fast Ethernet is an extension to its predecessor 10 Mbps Ethernet, providing a 10x increase in transmission rate. 100VG-AnyLAN offers extensions to Ethernet but embraces the Token Ring technology, allowing internetworking and better performance for networked video. ATM takes a radial approach by simplifying the information quantum to a 53-byte cell, resulting in rapid data handling for telecommunications equipment and allowing efficient transport of data, video, and voice communications. Switched Ethernet and Full Duplexing are among the other technologies competing for this market. The ultimate test of usefulness for any technology lies in how they handle the GIS environment requirements; working demonstration systems will help clarify marketing rhetoric and determine which vendor best implemented the standard.

  6. Reliability and concurrent validity of the computer workstation checklist.

    Science.gov (United States)

    Baker, Nancy A; Livengood, Heather; Jacobs, Karen

    2013-01-01

    Self-report checklists are used to assess computer workstation set up, typically by workers not trained in ergonomic assessment or checklist interpretation.Though many checklists exist, few have been evaluated for reliability and validity. This study examined reliability and validity of the Computer Workstation Checklist (CWC) to identify mismatches between workers' self-reported workstation problems. The CWC was completed at baseline and at 1 month to establish reliability. Validity was determined with CWC baseline data compared to an onsite workstation evaluation conducted by an expert in computer workstation assessment. Reliability ranged from fair to near perfect (prevalence-adjusted bias-adjusted kappa, 0.38-0.93); items with the strongest agreement were related to the input device, monitor, computer table, and document holder. The CWC had greater specificity (11 of 16 items) than sensitivity (3 of 16 items). The positive predictive value was greater than the negative predictive value for all questions. The CWC has strong reliability. Sensitivity and specificity suggested workers often indicated no problems with workstation setup when problems existed. The evidence suggests that while the CWC may not be valid when used alone, it may be a suitable adjunct to an ergonomic assessment completed by professionals.

  7. Design of a Workstation for People with Upper-Limb Disabilities Using a Brain Computer Interface

    Directory of Open Access Journals (Sweden)

    John E. Muñoz-Cardona

    2013-11-01

    Full Text Available  This paper shows the design of work-station for work-related inclusion people upper-limb disability. The system involves the use of novel brain computer interface used to bridge the user-computer interaction. Our hope objective is elucidating functional, technological, ergonomic and procedural aspects to runaway operation station; with propose to scratch barrier to impossibility access to TIC’s tools and work done for individual disability person. We found access facility ergonomics, adaptability and portable issue of workstation are most important design criteria. Prototype implementations in workplace environment have TIR estimate of 43% for retrieve. Finally we list a typology of services that could be the most appropriate for the process of labor including: telemarketing, telesales, telephone surveys, order taking, social assistance in disasters, general information and inquiries, reservations at tourist sites, technical support, emergency, online support and after-sales services.

  8. On Money as a Means of Coordination between Network Packets

    OpenAIRE

    Efraimidis, Pavlos S.; Koutsiamanis, Remous-Aris

    2012-01-01

    In this work, we apply a common economic tool, namely money, to coordinate network packets. In particular, we present a network economy, called PacketEconomy, where each flow is modeled as a population of rational network packets, and these packets can self-regulate their access to network resources by mutually trading their positions in router queues. Every packet of the economy has its price, and this price determines if and when the packet will agree to buy or sell a better position. We co...

  9. Outer packet sets and feature prediction of computer virus

    Science.gov (United States)

    Zhang, Ling

    2014-10-01

    The packet sets model was proposed by Prof. Shi in 2008. A packet sets is a set pair composed of internal and outer packet sets, and it has dynamic characteristic. Using packet sets theory, this paper gives the feature prediction of computer virus based on outer packet sets. The concept of virus screening-filtering is given, furthermore, the virus screening-filtering order theorem, composite virus screening-filtering theorem and virus screening-filtering rule are presented. A prediction method of computer virus feature is given based on the results. The outer packet sets is a new tool in the research of the prediction of dynamic virus feature.

  10. On the localization of Rydberg wave packets

    Science.gov (United States)

    Chatterjee, Supriya; Saha, Aparna; Talukdar, Benoy

    2013-11-01

    The Husimi distribution function is used to study the phase-space localization of Rydberg wave packets produced in a quasi one-dimensional hydrogen atom by the impact of half-cycle pulses (HCPs). The wave packet in a single-kicked atom exhibits transient phase-space localization. A weak second time-delayed HCP is found to extend the time of localization provided it is applied when the wave packet is near the inner turning point of the classical electron trajectory and momentum-transfer vectors of the first and the second kicks have the same sign. Alternatively, application of a similar second HCP increases the atomic ionization probability if the momentum-transfer vectors of the two kicks have opposite directions.

  11. New Photonic System for Optical Packet Switching

    Directory of Open Access Journals (Sweden)

    F. Rudge Barbosa

    2003-08-01

    Full Text Available Fast optical switching (ms timebase is realized by using a RF frequency tone inserted in the optical packet that carries a digital payload. By using a highly selective RF filtering for optical packet header frequency recognition, we have obtained excellent performance in optical switching function.. The RF header is detected at optical node input, and signals the node switching control, which instantly directs the packet to a prescribed output. No electronic processing of the digital payload is performed. The optical circuit is noise-free, has very low crosstalk, and is extremely selective in header frequency detection. BER measurements for payload consistently yield figures as low as 10-12 . This system is applicable to optical metropolitan and access networks, and is fully compatible with DWDM systems.

  12. Huge capacity optical packet switching and buffering.

    Science.gov (United States)

    Shinada, Satoshi; Furukawa, Hideaki; Wada, Naoya

    2011-12-12

    We demonstrate 2.56 Tbit/s/port dual-polarization DWDM/DQPSK variable-length optical packet (20 Gbit/s × 64 wavelengths × 2 polarizations) switching and buffering by using a 2×2 optical packet switch (OPS) system. The optical data plane of the OPS system was constructed of multi-connected electro-optical switches and fiber delay lines. The accumulated polarization dependent loss of each optical path in the data plane was less than 5 dB. This low-polarization-dependence OPS system enabled us to handle DWDM/DQPSK optical packets (1.28 Tbit/s/port) with time-varying polarization after transmission through 100 km fiber in the field. © 2011 Optical Society of America

  13. Cyber-workstation for computational neuroscience

    Directory of Open Access Journals (Sweden)

    Jack DiGiovanna

    2010-01-01

    Full Text Available A Cyber-Workstation (CW to study in vivo, real-time interactions between computational models and large-scale brain subsystems during behavioral experiments has been designed and implemented. The design philosophy seeks to directly link the in vivo neurophysiology laboratory with scalable computing resources to enable more sophisticated computational neuroscience investigation. The architecture designed here allows scientists develop new models and integrate them with existing models (e.g. recursive least-squares regressor by specifying appropriate connection in a block-diagram. Then, adaptive middleware transparently implements these user specifications using the full power of remote grid-computing hardware. In effect, the middleware deploys an on-demand and flexible neuroscience research test-bed to provide the neurophysiology laboratory extensive computational power from an outside source. The CW consolidates distributed software and hardware resources to support time-critical and/or resource-demanding computing during data collection from behaving animals. This power and flexibility is important as experimental and theoretical neuroscience evolves based on insights gained from data-intensive experiments, new technologies and engineering methodologies. This paper describes briefly the computational infrastructure and its most relevant components. Each component is discussed within a systematic process of setting up an in vivo, neuroscience experiment. Furthermore, a co-adaptive brain machine interface is implemented on the CW to illustrate how this integrated computational and experimental platform can be used to study systems neurophysiology and learning in a behavior task. We believe this implementation is also the first remote execution and adaptation of a brain-machine interface.

  14. SIMULASI JARINGAN KOMPUTER MENGGUNAKAN CISCO PACKET TRACER

    Directory of Open Access Journals (Sweden)

    M Mufadhol

    2012-01-01

    Full Text Available Perkembangan jaringan komputer saat ini begitu pesat, monitoring jaringan komputer akan menjadi suatu hal yang sulit dan rumit. Koneksi jaringan komputer merupakan suatu hal yang mendasar dalam suatu jaringan, karena bila koneksi itu bermasalah maka semua jenis aplikasi yang dijalankan melalui jaringan komputer tidak dapat digunakan. Cisco packet tracer dapat digunakan untuk simulasi yang mencerminkan arsitektur dan juga model dari jaringan komputer pada sistem jaringan yang digunakan. Dengan menggunakan aplikasi cisco packet tracer, simulasi mengenai jaringan dapat dimanfaatkan menjadi informasi tentang keadaan koneksi komputer dalam suatu jaringan.

  15. Determination of dynamic doxorubicin-EC50 value in an automated high-content workstation for cellular assays.

    Science.gov (United States)

    Wolf, Peter; Hartl, Florian; Brischwein, Martin; Wolf, Bernhard

    2011-12-01

    To overcome the problems of endpoint tests routinely required for EC50 determination, we utilized a novel automated high-content workstation and calculated a time-resolved EC50 value of MCF-7 mamma carcinoma cells treated with a pharmacologic agent. Measuring parameters were the cellular oxygen consumption and the extracellular acidification. These parameters were detected in real-time and label free with optochemical sensor spots in a modified 24-well sensor plate. In particular, the objective was to compare the measuring data of the workstation with a classical standard resazurin cell assay and to transfer the benefit of continuously recorded metabolic data of the workstation to practical time-resolved information about the effect of the applied active reagent (doxorubicin). MCF-7 cells were treated with a broad range of doxorubicin concentrations (100 μM to 1 nM) over 24 h and cellular activities were investigated with both, the resazurin assay and the automated workstation. Twenty-four hours after treatment, the resazurin assay showed an EC50 value (6.3 μM) which was about one decade above the value obtained from oxygen consumption rate (0.37 μM) and extracellular acidification rate (0.72 μM), measured with the workstation. Presumably, the differences are due to the different metabolic nature and regulation behind these measuring parameters. By polynomial fitting of continuously recorded metabolic data, we were able to point out a dynamic, time-resolved EC50 characteristic for different time points. The workstation is a powerful tool to record in vitro kinetic data of pharmacologic effects in vital cells in an automated experimental run. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. CASSINI S INMS TELEMETRY PACKET DATA V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The Cassini Ion and Neutral Mass Spectrometer (INMS) Packet data set contains all telemetry packets as received from the instrument. One standard product data type...

  17. A Neuro-Oncology Workstation for Structuring, Modeling, and Visualizing Patient Records.

    Science.gov (United States)

    Hsu, William; Arnold, Corey W; Taira, Ricky K

    2010-11-01

    The patient medical record contains a wealth of information consisting of prior observations, interpretations, and interventions that need to be interpreted and applied towards decisions regarding current patient care. Given the time constraints and the large-often extraneous-amount of data available, clinicians are tasked with the challenge of performing a comprehensive review of how a disease progresses in individual patients. To facilitate this process, we demonstrate a neuro-oncology workstation that assists in structuring and visualizing medical data to promote an evidence-based approach for understanding a patient's record. The workstation consists of three components: 1) a structuring tool that incorporates natural language processing to assist with the extraction of problems, findings, and attributes for structuring observations, events, and inferences stated within medical reports; 2) a data modeling tool that provides a comprehensive and consistent representation of concepts for the disease-specific domain; and 3) a visual workbench for visualizing, navigating, and querying the structured data to enable retrieval of relevant portions of the patient record. We discuss this workstation in the context of reviewing cases of glioblastoma multiforme patients.

  18. Molecular state reconstruction by nonlinear wave packet interferometry.

    Science.gov (United States)

    Humble, Travis S; Cina, Jeffrey A

    2004-08-06

    We show that time- and phase-resolved two-color nonlinear wave packet interferometry can be used to reconstruct the probability amplitude of an optically prepared molecular wave packet without prior knowledge of the underlying potential surface. We analyze state reconstruction in pure- and mixed-state model systems excited by shaped laser pulses and propose nonlinear wave packet interferometry as a tool for identifying optimized wave packets in coherent control experiments.

  19. Survival of the Fittest: An Active Queue Management Technique for Noisy Packet Flows

    Directory of Open Access Journals (Sweden)

    Shirish S. Karande

    2007-01-01

    Full Text Available We present a novel active queue management (AQM technique to demonstrate the efficacy of practically harnessing the predictive utility of SSR indications for improved video communication. We consider a network within which corrupted packets are relayed over multiple hops, but a certain percentage of packets needs to be dropped at an intermediate node due to congestion. We propose an AQM technique, survival of the fittest (SOTF, to be employed at the relay node, within which we use packet state information, available from SSR indications and checksums, to drop packets with the highest corruption levels. On the basis of actual 802.11b measurements we show that such a side information (SI aware processing within the network can provide significant performance benefits over an SI-unaware scheme, random queue management (RQM, which is forced to randomly discard packets. With trace-based simulations, we show the utility of the proposed AQM technique in improving the error recovery performance of cross-layer FEC schemes. Finally, with the help of H.264-based video simulations these improvements are shown to translate into a significant improvement in video quality.

  20. Peninsula Humane Society Teacher's Packet. Secondary Level.

    Science.gov (United States)

    Peninsula Humane Society, San Mateo, CA.

    Activities in this teacher's packet are designed to familiarize secondary school students with the responsibilities involved in pet ownership. Teaching plans are provided for a total of 12 lessons grouped under social studies, language arts, math, and health sciences. Activities focus on pet overpopulation, expressions of social responses in…

  1. Issues in Satellite Packet Video Communication.

    Science.gov (United States)

    1983-07-01

    i.o . .. . . _ _: .. ,: -t - .. . ..:’, • ... . . . ... . . . j.. - . ". 4 ISSUES IN SATELLITE PACKET VIDEO COMMUNICATIO \\ For the transmitter: 1. Get...No. 4469. Ma. 1981. 4. Forgie. James W., ST- A Proposed Internet Stream Protocol, M.I.T. Lincoln Laboratory, IEN 119, September 1979. 5. Jam. A. K

  2. Solid Waste Activity Packet for Teachers.

    Science.gov (United States)

    Illinois Univ., Urbana. Cooperative Extension Service.

    This solid waste activity packet introduces students to the solid waste problem in Illinois. Topics explore consumer practices in the market place, packaging, individual and community garbage generation, and disposal practices. The activities provide an integrated approach to incorporating solid waste management issues into subject areas. The…

  3. Impact of Packet Sampling on Link Dimensioning

    NARCIS (Netherlands)

    Schmidt, R.D.O.; Sadre, R.; Sperotto, A.; Berg, H. van den; Pras, A.

    2015-01-01

    Link dimensioning is used by network operators to properly provision the capacity of their network links. Proposed methods for link dimensioning often require statistics, such as traffic variance, that need to be calculated from packet-level measurements. In practice, due to increasing traffic

  4. The Impact of Ergonomically Designed Workstations on Shoulder EMG Activity during Carpet Weaving.

    Science.gov (United States)

    Motamedzade, Majid; Afshari, Davood; Soltanian, Alireza

    2014-01-01

    The present study aimed to evaluate the biomechanical exposure to the trapezius muscle activity in female weavers for a prolonged period in the workstation A (suggested by previous studies) and workstation B (proposed by the present study). Electromyography data were collected from nine females during four hours for each ergonomically designed workstation at the Ergonomics Laboratory, Hamadan, Iran. The design criteria for ergonomically designed workstations were: 1) weaving height (20 and 3 cm above elbow height for workstations A and B, respectively), and 2) seat type (10° and 0° forwardsloping seat for workstations A and B, respectively). The amplitude probability distribution function (APDF) analysis showed that the left and right upper trapezius muscle activity was almost similar at each workstation. Trapezius muscle activity in the workstation A was signifi-cantly greater than workstations B (Pweaving may be associated with musculoskeletal symptoms.

  5. Muscle activity patterns and spinal shrinkage in office workers using a sit-stand workstation versus a sit workstation.

    Science.gov (United States)

    Gao, Ying; Cronin, Neil J; Pesola, Arto J; Finni, Taija

    2016-10-01

    Reducing sitting time by means of sit-stand workstations is an emerging trend, but further evidence is needed regarding their health benefits. This cross-sectional study compared work time muscle activity patterns and spinal shrinkage between office workers (aged 24-62, 58.3% female) who used either a sit-stand workstation (Sit-Stand group, n = 10) or a traditional sit workstation (Sit group, n = 14) for at least the past three months. During one typical workday, muscle inactivity and activity from quadriceps and hamstrings were monitored using electromyography shorts, and spinal shrinkage was measured using stadiometry before and after the workday. Compared with the Sit group, the Sit-Stand group had less muscle inactivity time (66.2 ± 17.1% vs. 80.9 ± 6.4%, p = 0.014) and more light muscle activity time (26.1 ± 12.3% vs. 14.9 ± 6.3%, p = 0.019) with no significant difference in spinal shrinkage (5.62 ± 2.75 mm vs. 6.11 ± 2.44 mm). This study provides evidence that working with sit-stand workstations can promote more light muscle activity time and less inactivity without negative effects on spinal shrinkage. Practitioner Summary: This cross-sectional study compared the effects of using a sit-stand workstation to a sit workstation on muscle activity patterns and spinal shrinkage in office workers. It provides evidence that working with a sit-stand workstation can promote more light muscle activity time and less inactivity without negative effects on spinal shrinkage.

  6. Segregation of helicity in inertial wave packets

    Science.gov (United States)

    Ranjan, A.

    2017-03-01

    Inertial waves are known to exist in the Earth's rapidly rotating outer core and could be important for the dynamo generation. It is well known that a monochromatic inertial plane wave traveling parallel to the rotation axis (along positive z ) has negative helicity while the wave traveling antiparallel (negative z ) has positive helicity. Such a helicity segregation, north and south of the equator, is necessary for the α2-dynamo model based on inertial waves [Davidson, Geophys. J. Int. 198, 1832 (2014), 10.1093/gji/ggu220] to work. The core is likely to contain a myriad of inertial waves of different wave numbers and frequencies. In this study, we investigate whether this characteristic of helicity segregation also holds for an inertial wave packet comprising waves with the same sign of Cg ,z, the z component of group velocity. We first derive the polarization relations for inertial waves and subsequently derive the resultant helicity in wave packets forming as a result of superposition of two or more waves. We find that the helicity segregation does hold for an inertial wave packet unless the wave numbers of the constituent waves are widely separated. In the latter case, regions of opposite color helicity do appear, but the mean helicity retains the expected sign. An illustration of this observation is provided by (a) calculating the resultant helicity for a wave packet formed by superposition of four upward-propagating inertial waves with different wave vectors and (b) conducting the direct numerical simulation of a Gaussian eddy under rapid rotation. Last, the possible effects of other forces such as the viscous dissipation, the Lorentz force, buoyancy stratification, and nonlinearity on helicity are investigated and discussed. The helical structure of the wave packet is likely to remain unaffected by dissipation or the magnetic field, but can be modified by the presence of linearly stable stratification and nonlinearity.

  7. Method and allocation device for allocating pending requests for data packet transmission at a number of inputs to a number of outputs of a packet switching device in successive time slots

    Science.gov (United States)

    Abel, Francois; Iliadis, Ilias; Minkenberg, Cyriel J. A.

    2009-02-03

    A method for allocating pending requests for data packet transmission at a number of inputs to a number of outputs of a switching system in successive time slots, including a matching method including the steps of providing a first request information in a first time slot indicating data packets at the inputs requesting transmission to the outputs of the switching system, performing a first step in the first time slot depending on the first request information to obtain a first matching information, providing a last request information in a last time slot successive to the first time slot, performing a last step in the last time slot depending on the last request information and depending on the first matching information to obtain a final matching information, and assigning the pending data packets at the number of inputs to the number of outputs based on the final matching information.

  8. A standardized non-instrumental tool for characterizing workstations concerned with exposure to engineered nanomaterials

    Science.gov (United States)

    Canu I, Guseva; C, Ducros; S, Ducamp; L, Delabre; S, Audignon-Durand; C, Durand; Y, Iwatsubo; D, Jezewski-Serra; Bihan O, Le; S, Malard; A, Radauceanu; M, Reynier; M, Ricaud; O, Witschger

    2015-05-01

    The French national epidemiological surveillance program EpiNano aims at surveying mid- and long-term health effects possibly related with occupational exposure to either carbon nanotubes or titanium dioxide nanoparticles (TiO2). EpiNano is limited to workers potentially exposed to these nanomaterials including their aggregates and agglomerates. In order to identify those workers during the in-field industrial hygiene visits, a standardized non-instrumental method is necessary especially for epidemiologists and occupational physicians unfamiliar with nanoparticle and nanomaterial exposure metrology. A working group, Quintet ExpoNano, including national experts in nanomaterial metrology and occupational hygiene reviewed available methods, resources and their practice in order to develop a standardized tool for conducting company industrial hygiene visits and collecting necessary information. This tool, entitled “Onsite technical logbook”, includes 3 parts: company, workplace, and workstation allowing a detailed description of each task, process and exposure surrounding conditions. This logbook is intended to be completed during the company industrial hygiene visit. Each visit is conducted jointly by an industrial hygienist and an epidemiologist of the program and lasts one or two days depending on the company size. When all collected information is computerized using friendly-using software, it is possible to classify workstations with respect to their potential direct and/or indirect exposure. Workers appointed to workstations classified as concerned with exposure are considered as eligible for EpiNano program and invited to participate. Since January 2014, the Onsite technical logbook has been used in ten company visits. The companies visited were mostly involved in research and development. A total of 53 workstations with potential exposure to nanomaterials were pre-selected and observed: 5 with TiO2, 16 with single-walled carbon nanotubes, 27 multiwalled

  9. Classroom evaluation of the Arlyn Arm robotic workstation.

    Science.gov (United States)

    Eberhardt, S P; Osborne, J; Rahman, T

    2000-01-01

    High school and junior high school students with neuromuscular weakness and other disorders of the arms evaluated a recently commercialized robotic workstation, the Arlyn Arm, to carry out art projects and science experiments. These tasks were designed for independent execution with the workstation using standard or custom-designed tools. Each task was divided into subtasks, and the execution time of each subtask was determined as a measure of efficiency. Special attention was given to the causes of required experimenter intervention. While subjects easily accomplished some subtasks, others required considerable intervention. Most of these interventions could be avoided by further customizing accessories. It is concluded that the Arlyn Arm workstation could be of considerable benefit in a classroom setting to persons with severe neuromuscular disorders.

  10. Advanced human machine interaction for an image interpretation workstation

    Science.gov (United States)

    Maier, S.; Martin, M.; van de Camp, F.; Peinsipp-Byma, E.; Beyerer, J.

    2016-05-01

    In recent years, many new interaction technologies have been developed that enhance the usability of computer systems and allow for novel types of interaction. The areas of application for these technologies have mostly been in gaming and entertainment. However, in professional environments, there are especially demanding tasks that would greatly benefit from improved human machine interfaces as well as an overall improved user experience. We, therefore, envisioned and built an image-interpretation-workstation of the future, a multi-monitor workplace comprised of four screens. Each screen is dedicated to a complex software product such as a geo-information system to provide geographic context, an image annotation tool, software to generate standardized reports and a tool to aid in the identification of objects. Using self-developed systems for hand tracking, pointing gestures and head pose estimation in addition to touchscreens, face identification, and speech recognition systems we created a novel approach to this complex task. For example, head pose information is used to save the position of the mouse cursor on the currently focused screen and to restore it as soon as the same screen is focused again while hand gestures allow for intuitive manipulation of 3d objects in mid-air. While the primary focus is on the task of image interpretation, all of the technologies involved provide generic ways of efficiently interacting with a multi-screen setup and could be utilized in other fields as well. In preliminary experiments, we received promising feedback from users in the military and started to tailor the functionality to their needs

  11. Random linear network coding for streams with unequally sized packets

    DEFF Research Database (Denmark)

    Taghouti, Maroua; Roetter, Daniel Enrique Lucani; Pedersen, Morten Videbæk

    2016-01-01

    State of the art Random Linear Network Coding (RLNC) schemes assume that data streams generate packets with equal sizes. This is an assumption that results in the highest efficiency gains for RLNC. A typical solution for managing unequal packet sizes is to zero-pad the smallest packets. However...... of packets, which are strategies that require additional signalling. Performance is evaluated using CAIDA TCP packets and 4k video traces. Our results show that our mechanisms reduce significantly the padding overhead even for small field sizes. Finally, our strategies provide a natural trade-off between...

  12. Sparse Packetized Predictive Control for Networked Control over Erasure Channels

    DEFF Research Database (Denmark)

    Nagahara, Masaaki; Quevedo, Daniel E.; Østergaard, Jan

    2014-01-01

    We study feedback control over erasure channels with packet-dropouts. To achieve robustness with respect to packet-dropouts, the controller transmits data packets containing plant input predictions, which minimize a finite horizon cost function. To reduce the data size of packets, we propose...... to adopt sparsity-promoting optimizations, namely, l1 - l2 and l2-constrained l0 optimizations, for which efficient algorithms exist. We show how to design the tuning parameters to ensure (practical) stability of the resulting feedback control systems when the number of consecutive packet...

  13. A New Texture Synthesis Algorithm Based on Wavelet Packet Tree

    Directory of Open Access Journals (Sweden)

    Hsi Chin Hsin

    2012-01-01

    Full Text Available This paper presents an efficient texture synthesis based on wavelet packet tree (TSWPT. It has the advantage of using a multiresolution representation with a greater diversity of bases functions for the nonlinear time series applications such as fractal images. The input image is decomposed into wavelet packet coefficients, which are rearranged and organized to form hierarchical trees called wavelet packet trees. A 2-step matching, that is, coarse matching based on low-frequency wavelet packet coefficients followed by fine matching based on middle-high-frequency wavelet packet coefficients, is proposed for texture synthesis. Experimental results show that the TSWPT algorithm is preferable, especially in terms of computation time.

  14. On the Effects of Heterogeneous Packet Lengths on Network Coding

    DEFF Research Database (Denmark)

    Compta, Pol Torres; Fitzek, Frank; Roetter, Daniel Enrique Lucani

    2014-01-01

    Random linear network coding (RLNC) has been shown to provide increased throughput, security and robustness for the transmission of data through the network. Most of the analysis and the demonstrators have focused on the study of data packets with the same size (number of bytes). This constitutes...... a best case scenario as coded packets will incur little overhead to handle such packets. However, packet lengths are quite heterogeneous in real networks, which can cause a high overhead or, alternatively, a high delay in the transmission of data packets. As we show, this can have a severe effect...... on a variety of applications. This paper proposes a series of mechanisms to manage heterogeneous packet lengths and analyzes the induced overhead of those mechanisms using real packet length distributions provided by CAIDA and own measurements using video content. Our results show that an appropriate...

  15. Video display terminal workstation improvement program: I. Baseline associations between musculoskeletal discomfort and ergonomic features of workstations.

    Science.gov (United States)

    Demure, B; Luippold, R S; Bigelow, C; Ali, D; Mundt, K A; Liese, B

    2000-08-01

    Associations between selected sites of musculoskeletal discomfort and ergonomic characteristics of the video display terminal (VDT) workstation were assessed in analyses controlling for demographic, psychosocial stress, and VDT use factors in 273 VDT users from a large administrative department. Significant associations with wrist/hand discomfort were seen for female gender; working 7+ hours at a VDT; low job satisfaction; poor keyboard position; use of new, adjustable furniture; and layout of the workstation. Significantly increased odds ratios for neck/shoulder discomfort were observed for 7+ hours at a VDT, less than complete job control, older age (40 to 49 years), and never/infrequent breaks. Lower back discomfort was related marginally to working 7+ hours at a VDT. These results demonstrate that some characteristics of VDT workstations, after accounting for psychosocial stress, can be correlated with musculoskeletal discomfort.

  16. Spatiotemporal Imaging of Ultrafast Molecular Motion: Collapse and Revival of the D2+ Nuclear Wave Packet

    Science.gov (United States)

    Ergler, Th.; Rudenko, A.; Feuerstein, B.; Zrost, K.; Schröter, C. D.; Moshammer, R.; Ullrich, J.

    2006-11-01

    We report on a real-time imaging of the ultrafast D2+ rovibrational nuclear wave-packet motion performed using a combination of a pump-probe setup with 7 fs laser pulses and a “reaction-microscope” spectrometer. We observe fast dephasing (collapse) of the vibrational wave packet and its subsequent revival and prove rotational excitation in ultrashort laser pulses. Channel-selective Fourier analysis of the wave packet’s long-term (˜3000fs) evolution allows us to resolve its individual constituents, revealing unique information on the mechanisms of strong-field ionization and dissociation.

  17. Dynamic Average Consensus and Consensusability of General Linear Multiagent Systems with Random Packet Dropout

    Directory of Open Access Journals (Sweden)

    Wen-Min Zhou

    2013-01-01

    Full Text Available This paper is concerned with the consensus problem of general linear discrete-time multiagent systems (MASs with random packet dropout that happens during information exchange between agents. The packet dropout phenomenon is characterized as being a Bernoulli random process. A distributed consensus protocol with weighted graph is proposed to address the packet dropout phenomenon. Through introducing a new disagreement vector, a new framework is established to solve the consensus problem. Based on the control theory, the perturbation argument, and the matrix theory, the necessary and sufficient condition for MASs to reach mean-square consensus is derived in terms of stability of an array of low-dimensional matrices. Moreover, mean-square consensusable conditions with regard to network topology and agent dynamic structure are also provided. Finally, the effectiveness of the theoretical results is demonstrated through an illustrative example.

  18. A Packetized SPIHT Algorithm with Overcomplete Wavelet Coefficients for Increased Robustness

    Directory of Open Access Journals (Sweden)

    Sriraja Y

    2006-01-01

    Full Text Available This paper presents a wavelet-based image encoding scheme with error resilience and error concealment suitable for transmission over networks prone to packet losses. The scheme involves partitioning the data into independent descriptions of roughly equal lengths, achieved by a combination of packetization and modifications to the wavelet tree structure without additional redundancy. With a weighted-averaging-based interpolation method, our proposed encoding scheme attains an improvement of about 0.5–1.5 dB in PSNR over other similar methods. We also investigate the use of overcomplete wavelet transform coefficients as side information for our encoding scheme to improve the error resilience when severe packet losses occur. Experiments show that we are able to achieve a high coding performance along with a good perceptual quality for the reconstructed image.

  19. Multiple descriptions for packetized predictive control

    DEFF Research Database (Denmark)

    Østergaard, Jan; Quevedo, Daniel

    2016-01-01

    In this paper, we propose to use multiple descriptions (MDs) to achieve a high degree of robustness towards random packet delays and erasures in networked control systems. In particular, we consider the scenario, where a data-rate limited channel is located between the controller and the plant...... input. This forward channel also introduces random delays and dropouts. The feedback channel from the plant output to the controller is assumed noiseless. We show how to design MDs for packetized predicted control (PPC) in order to enhance the robustness. In the proposed scheme, a quantized control...... be reliably reconstructed at the plant side. For the particular case of LTI plant models and i.i.d. channels, we show that the overall system forms a Markov jump linear system. We provide conditions for mean square stability and derive upper bounds on the operational bit rate of the quantizer to guarantee...

  20. Experimental Packet Radio System Design Plan

    Science.gov (United States)

    1974-03-13

    HERBEP ♦ PftCKET ♦HEfiL’ER ♦PACKET ♦ IMP ICl=iTnR£*SEEUENCE* TD DP FrtDM ♦LENGTH ♦LENGTH ♦TYPE ♦ ♦NUMIER ♦STPTIDN ♦ ♦ IN...5 .olts and -12 volts. The electrical operating properties are listed below: 256 x 8 1024 y 16 QUIESCENT DEVICE CURRENT 55M - 440M- ACC ESS

  1. Turbulent Spot Pressure Fluctuation Wave Packet Model

    Energy Technology Data Exchange (ETDEWEB)

    Dechant, Lawrence J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-05-01

    Wave packet analysis provides a connection between linear small disturbance theory and subsequent nonlinear turbulent spot flow behavior. The traditional association between linear stability analysis and nonlinear wave form is developed via the method of stationary phase whereby asymptotic (simplified) mean flow solutions are used to estimate dispersion behavior and stationary phase approximation are used to invert the associated Fourier transform. The resulting process typically requires nonlinear algebraic equations inversions that can be best performed numerically, which partially mitigates the value of the approximation as compared to a more complete, e.g. DNS or linear/nonlinear adjoint methods. To obtain a simpler, closed-form analytical result, the complete packet solution is modeled via approximate amplitude (linear convected kinematic wave initial value problem) and local sinusoidal (wave equation) expressions. Significantly, the initial value for the kinematic wave transport expression follows from a separable variable coefficient approximation to the linearized pressure fluctuation Poisson expression. The resulting amplitude solution, while approximate in nature, nonetheless, appears to mimic many of the global features, e.g. transitional flow intermittency and pressure fluctuation magnitude behavior. A low wave number wave packet models also recover meaningful auto-correlation and low frequency spectral behaviors.

  2. Counter-propagating patterns in the BioPhotonics Workstation

    DEFF Research Database (Denmark)

    Palima, Darwin; Lindballe, T.; Kristensen, M.V.

    2010-01-01

    The counter-propagating geometry opens an extra degree of freedom for shaping light while subsuming single-sided illumination as a special case (i.e., one beam set turned off). In its conventional operation, our BioPhotonics Workstation (BWS) uses symmetric, co-axial counter-propagating beams...

  3. Ergonomics in the computer workstation | Karoney | East African ...

    African Journals Online (AJOL)

    Background: Awareness of effects of long term use of computer and application of ergonomics in the computer workstation is important for preventing musculoskeletal disorders, eyestrain and psychosocial effects. Objectives: To determine the awareness of ºphysical and psychological effects of prolonged computer usage ...

  4. Post-deployment usability evaluation of a radiology workstation

    NARCIS (Netherlands)

    Jorritsma, Wiard; Cnossen, Fokie; Dierckx, Rudi; Oudkerk, Matthijs; van Ooijen, Peter

    2015-01-01

    Objective To evaluate the usability of a radiology workstation after deployment in a hospital. Significance In radiology, it is difficult to perform valid pre-deployment usability evaluations due to the heterogeneity of the user group, the complexity of the radiological workflow, and the complexity

  5. Automated workstation for the operation of spacecraft engineering subsystems

    Science.gov (United States)

    Bahrami, K. A.; Atkins, K. L.; Saxon, R.; Kaufman, N.

    1988-01-01

    This paper addresses the development of a workstation that exploits automated tools to enable an operator to monitor concurrently several engineering subsystems and/or several space missions. The use of artificial intelligence and advanced graphics capabilities to achieve fast prototypes is discussed. The monitoring of engineering telemetry data from the Power and Pyro Subsystem of the Galileo spacecraft is emphasized.

  6. Providing Independent Reading Comprehension Strategy Practice through Workstations

    Science.gov (United States)

    Young, Chase

    2014-01-01

    This article describes an action research project undertaken by a second grade teacher looking for research-based ways to increase his students' reading comprehension. He designed fifteen comprehension workstations and evaluated their effect on his second graders' reading comprehension scores as measured by district Imagination Station…

  7. The Impact of Ergonomically Designed Workstations on Shoulder EMG Activity during Carpet Weaving

    Science.gov (United States)

    Motamedzade, Majid; Afshari, Davood; Soltanian, Alireza

    2014-01-01

    Background: The present study aimed to evaluate the biomechanical exposure to the trapezius muscle activity in female weavers for a prolonged period in the workstation A (suggested by previous studies) and workstation B (proposed by the present study). Methods: Electromyography data were collected from nine females during four hours for each ergonomically designed workstation at the Ergonomics Laboratory, Hamadan, Iran. The design criteria for ergonomically designed workstations were: 1) weaving height (20 and 3 cm above elbow height for workstations A and B, respectively), and 2) seat type (10° and 0° forwardsloping seat for workstations A and B, respectively). Results: The amplitude probability distribution function (APDF) analysis showed that the left and right upper trapezius muscle activity was almost similar at each workstation. Trapezius muscle activity in the workstation A was signifi­cantly greater than workstations B (P<0.001). Conclusion: In general, use of workstation B leads to significantly reduced muscle activity levels in the upper trapezius as compared to workstation A in weavers. Despite the positive impact of workstation B in reducing trapezius muscle activity, it seems that constrained postures of the upper arm during weaving may be associated with musculoskeletal symptoms. PMID:25650180

  8. Assessment of pancreatic tumor resectability with multidetector computed tomography: semiautomated console-generated images versus dedicated workstation-generated images.

    Science.gov (United States)

    Singh, Anand K; Sahani, Dushyant V; Blake, Michael A; Joshi, Mukta C; Wargo, Jennifer A; Fernandez-del Castillo, Carlos

    2008-08-01

    The purpose of this retrospective study was to compare the maximum intensity projection (MIP) images generated at a multidetector computed tomography (MDCT) scanner console using advanced tools at a three-dimensional (3D) workstation for assessment of pancreatic tumor resectability. Institutional review board approval and informed consent wavier were obtained for this retrospective study. The intraoperative findings were used as reference standard. Two radiologists assessed console MIPs that were created using computed tomographic (CT) data sets of 30 patients (17 men and 13 women; age range, 35-79 years; mean age, 58 years) operated for pancreatic tumors. Semi-automated MIP images were created on a separate MDCT console. Two blinded radiologist (R1, R2) and surgeons (S1, S2) evaluated the image data independently for vascular involvement and tumor resectability. The image quality and diagnostic confidence for MIPs were graded on a 5-point scale (1 = poor, 2 = suboptimal, 3 = intermediate, 4 = good; 5 = excellent) and comparison was made with 3D workstation image scores. The findings revealed greater than 90% sensitivity, specificity, and accuracy for detecting involvement of peripancreatic vessels by pancreatic tumor with an excellent interobserver agreement (kappa = 0.87-1.00). The findings of console-generated MIPs were same as the findings of 3D workstation images. The mean of image quality and diagnostic confidence grading for console MIPs by assessors were 4.4 and 4.2, respectively. The average time to generate simple MIPs at the console was 3.4 minutes (range, 2.3-4.4) compared to 26 minutes (range, 18-33) to create images at the 3D workstation. Semi-automated MIPs generated from an MDCT scanner console is an excellent alternative to 3D workstation images for assessing resectability of pancreatic tumor based on vascular involvement. Console MIPs can be quickly generated during the time of scan and thus can improve CT workflow.

  9. Survey of ANL organization plans for word processors, personal computers, workstations, and associated software

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, K.R.; Rockwell, V.S.

    1992-08-01

    The Computing and Telecommunications Division (CTD) has compiled this Survey of ANL Organization plans for Word Processors, Personal Computers, Workstations, and Associated Software (ANL/TM, Revision 4) to provide DOE and Argonne with a record of recent growth in the acquisition and use of personal computers, microcomputers, and word processors at ANL. Laboratory planners, service providers, and people involved in office automation may find the Survey useful. It is for internal use only, and any unauthorized use is prohibited. Readers of the Survey should use it as a reference document that (1) documents the plans of each organization for office automation, (2) identifies appropriate planners and other contact people in those organizations and (3) encourages the sharing of this information among those people making plans for organizations and decisions about office automation. The Survey supplements information in both the ANL Statement of Site Strategy for Computing Workstations (ANL/TM 458) and the ANL Site Response for the DOE Information Technology Resources Long-Range Plan (ANL/TM 466).

  10. Survey of ANL organization plans for word processors, personal computers, workstations, and associated software. Revision 4

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, K.R.; Rockwell, V.S.

    1992-08-01

    The Computing and Telecommunications Division (CTD) has compiled this Survey of ANL Organization plans for Word Processors, Personal Computers, Workstations, and Associated Software (ANL/TM, Revision 4) to provide DOE and Argonne with a record of recent growth in the acquisition and use of personal computers, microcomputers, and word processors at ANL. Laboratory planners, service providers, and people involved in office automation may find the Survey useful. It is for internal use only, and any unauthorized use is prohibited. Readers of the Survey should use it as a reference document that (1) documents the plans of each organization for office automation, (2) identifies appropriate planners and other contact people in those organizations and (3) encourages the sharing of this information among those people making plans for organizations and decisions about office automation. The Survey supplements information in both the ANL Statement of Site Strategy for Computing Workstations (ANL/TM 458) and the ANL Site Response for the DOE Information Technology Resources Long-Range Plan (ANL/TM 466).

  11. The impact of neighboring infection on the computer virus spread in packets on scale-free networks

    Science.gov (United States)

    Lazfi, S.; Lamzabi, S.; Rachadi, A.; Ez-Zahraouy, H.

    2017-12-01

    In this paper, we introduce the effect of neighbors on the infection of packets by computer virus in the SI and SIR models using the minimal traffic routing protocol. We have applied this model to the Barabasi-Albert network to determine how intrasite and extrasite infection rates affect virus propagation through the traffic flow of information packets in both the free-flow and the congested phases. The numerical results show that when we change the intrasite infection rate λ1 while keeping constant the extrasite infection rate λ2, we get normal behavior in the congested phase: in the network, the proportion of infected packets increases to reach a peak and then decreases resulting in a simultaneous increase of the recovered packets. In contrast, when the intrasite infection rate λ1 is kept fixed, an increase of the extrasite infection rate results in two regimes: The first one is characterized by an increase of the proportion of infected packets until reaching some peak value and then decreases smoothly. The second regime is characterized by an increase of infected packets to some stationary value.

  12. Breastfeeding Resources in Maternity Hospitals and Birth Centers in the Commonwealth of Massachusetts (USA): A Content Analysis of Discharge Packets.

    Science.gov (United States)

    Eshelman, Jill; Edwards, Roger A; Ghiringhelli, Kara; Mainello, Kristen; Colchamiro, Rachel; Forgit, Julie; Tolan, Ellen; Nordstrom, Christina

    2015-11-01

    Few studies have analyzed patient education materials provided at discharge. To the best of our knowledge, there are no comprehensive studies analyzing and reporting the content of breastfeeding discharge packets within the United States. This study analyzed the extent to which patient education materials provided at discharge from maternity facilities in Massachusetts cover topics that support successful breastfeeding. We collected discharge packets from all 48 maternity hospitals/birth centers. Topics for analysis were based on recommendations associated with the Baby-Friendly Hospital Initiative and content identified for discharge packets generally. Materials were reviewed independently and scored according to 39 criteria that we assembled from various sources for optimal breastfeeding information at discharge. Bivariate and multivariate analyses were used to explore if any hospital characteristics predicted presence of breastfeeding education topics in written information provided at discharge. An average of 25.4 of 39 criteria (65.2%, ranging from 30.7%-97.4%) were included in packets submitted by all 48 facilities. Exploratory multivariate analyses did not show relationships of hospital characteristics to contents of packets. Each facility received a 2-page report noting strengths, suggestions for improvement, and individual scores on all 39 criteria. Discharge packet contents varied widely; whereas some institutions' information met and/or exceeded recommended content, others were limited and/or missing information. These analyses provide a thorough review of discharge packet content for all facilities in Massachusetts; however, further study is needed to identify the implications of such variation for breastfeeding outcomes. © The Author(s) 2015.

  13. The performance of multichannel, multihop packet radio networks

    Science.gov (United States)

    Shacham, Nachum; King, Peter J. B.

    The architecture for a packet radio network which utilizes parallel multihop multiple-access channels is proposed. Consideration is given to single and multichannel transmissions, routing in single and multichannel transmission systems, the quiescent channel, and nodes. The performance of multihop multichannel packet radio networks is evaluated; throughput and average packet progress per hop under slotted ALOHA and CSMA protocols are analyzed. It is noted that multichannel transmission provides no significant advantages over single channel transmission.

  14. Compressed Domain Packet Loss Concealment of Sinusoidally Coded Speech

    DEFF Research Database (Denmark)

    Rødbro, Christoffer A.; Christensen, Mads Græsbøll; Andersen, Søren Vang

    2003-01-01

    We consider the problem of packet loss concealment for voice over IP (VoIP). The speech signal is compressed at the transmitter using a sinusoidal coding scheme working at 8 kbit/s. At the receiver, packet loss concealment is carried out working directly on the quantized sinusoidal parameters......, based on time-scaling of the packets surrounding the missing ones. Subjective listening tests show promising results indicating the potential of sinusoidal speech coding for VoIP....

  15. Bacterial contamination of radiologist workstations: results of a pilot study.

    Science.gov (United States)

    Duszak, Richard; Lanier, Brandi; Tubbs, John A; Ogilvie, Mary; Thompson-Jaeger, Sandra

    2014-02-01

    The aim of this study was to quantify and characterize bacterial contamination of radiologist workstations. Dictation microphones and computer mice at the most frequently used radiologist workstations from 2 inpatient and 2 outpatient reading rooms at 2 teaching hospitals in 2 states were sampled for bacteria. Reference toilet seat and doorknob sampling was performed in the 4 restrooms nearest those reading rooms. One microphone and one mouse in each reading room were sampled again after quick disinfection with an inexpensive, commercially available antiseptic pad. Sampling was performed using direct trypticase soy agar plating, with sampled areas uniformly approximating 50 cm(2). Colonies were quantified and additionally characterized after 24 hours using mannitol salt agar and MacConkey agar. All sampled radiologist computer workstation and restroom sites were contaminated with bacteria. Mean colony counts were 69.4 ± 38.7 (range, 15-123) for microphones, 46.1 ± 58.1 (range, 1-173) for mice, 10.5 ± 9.7 (range, 1-22) for toilet seats, and 14.8 ± 16.0 (range, 1-36) for restroom doorknobs. Of all workstation sites, 64.3% (9 of 14) grew Staphylococcus aureus, and 21.4% (3 of 14) grew enteric organisms. Overall microphone and mouse bacterial contamination was significantly higher than that of nearby restroom toilets and doorknobs (57.8 ± 49.0 vs 12.6 ± 12.5, P = .005). Microphone and mouse bacterial counts were nearly completely eliminated after brief antiseptic swabbing (from 76.9 ± 53.2 to 0.3 ± 0.7, P = .002). Bacterial contamination of microphones and computer mice at radiologist workstations is common, with colonization significantly greater than nearby restroom toilet seats and doorknobs. Simple, rapid, and inexpensive disinfection techniques nearly completely eradicate workstation bacterial contamination. The clinical implications of colonization merits further study. Copyright © 2014 American College of Radiology. Published by Elsevier Inc. All rights

  16. A collaborative approach to lean laboratory workstation design reduces wasted technologist travel.

    Science.gov (United States)

    Yerian, Lisa M; Seestadt, Joseph A; Gomez, Erron R; Marchant, Kandice K

    2012-08-01

    Lean methodologies have been applied in many industries to reduce waste. We applied Lean techniques to redesign laboratory workstations with the aim of reducing the number of times employees must leave their workstations to complete their tasks. At baseline in 68 workflows (aggregates or sequence of process steps) studied, 251 (38%) of 664 tasks required workers to walk away from their workstations. After analysis and redesign, only 59 (9%) of the 664 tasks required technologists to leave their workstations to complete these tasks. On average, 3.4 travel events were removed for each workstation. Time studies in a single laboratory section demonstrated that workers spend 8 to 70 seconds in travel each time they step away from the workstation. The redesigned workstations will allow employees to spend less time travelling around the laboratory. Additional benefits include employee training in waste identification, improved overall laboratory layout, and identification of other process improvement opportunities in our laboratory.

  17. Analysis of cutting force signals by wavelet packet transform for surface roughness monitoring in CNC turning

    Science.gov (United States)

    García Plaza, E.; Núñez López, P. J.

    2018-01-01

    On-line monitoring of surface finish in machining processes has proven to be a substantial advancement over traditional post-process quality control techniques by reducing inspection times and costs and by avoiding the manufacture of defective products. This study applied techniques for processing cutting force signals based on the wavelet packet transform (WPT) method for the monitoring of surface finish in computer numerical control (CNC) turning operations. The behaviour of 40 mother wavelets was analysed using three techniques: global packet analysis (G-WPT), and the application of two packet reduction criteria: maximum energy (E-WPT) and maximum entropy (SE-WPT). The optimum signal decomposition level (Lj) was determined to eliminate noise and to obtain information correlated to surface finish. The results obtained with the G-WPT method provided an in-depth analysis of cutting force signals, and frequency ranges and signal characteristics were correlated to surface finish with excellent results in the accuracy and reliability of the predictive models. The radial and tangential cutting force components at low frequency provided most of the information for the monitoring of surface finish. The E-WPT and SE-WPT packet reduction criteria substantially reduced signal processing time, but at the expense of discarding packets with relevant information, which impoverished the results. The G-WPT method was observed to be an ideal procedure for processing cutting force signals applied to the real-time monitoring of surface finish, and was estimated to be highly accurate and reliable at a low analytical-computational cost.

  18. 40-Gbps optical backbone network deep packet inspection based on FPGA

    Science.gov (United States)

    Zuo, Yuan; Huang, Zhiping; Su, Shaojing

    2014-11-01

    In the era of information, the big data, which contains huge information, brings about some problems, such as high speed transmission, storage and real-time analysis and process. As the important media for data transmission, the Internet is the significant part for big data processing research. With the large-scale usage of the Internet, the data streaming of network is increasing rapidly. The speed level in the main fiber optic communication of the present has reached 40Gbps, even 100Gbps, therefore data on the optical backbone network shows some features of massive data. Generally, data services are provided via IP packets on the optical backbone network, which is constituted with SDH (Synchronous Digital Hierarchy). Hence this method that IP packets are directly mapped into SDH payload is named POS (Packet over SDH) technology. Aiming at the problems of real time process of high speed massive data, this paper designs a process system platform based on ATCA for 40Gbps POS signal data stream recognition and packet content capture, which employs the FPGA as the CPU. This platform offers pre-processing of clustering algorithms, service traffic identification and data mining for the following big data storage and analysis with high efficiency. Also, the operational procedure is proposed in this paper. Four channels of 10Gbps POS signal decomposed by the analysis module, which chooses FPGA as the kernel, are inputted to the flow classification module and the pattern matching component based on TCAM. Based on the properties of the length of payload and net flows, buffer management is added to the platform to keep the key flow information. According to data stream analysis, DPI (deep packet inspection) and flow balance distribute, the signal is transmitted to the backend machine through the giga Ethernet ports on back board. Practice shows that the proposed platform is superior to the traditional applications based on ASIC and NP.

  19. Monitoring and Indentification Packet in Wireless With Deep Packet Inspection Method

    Science.gov (United States)

    Fali Oklilas, Ahmad; Tasmi

    2017-04-01

    Layer 2 and Layer 3 are used to make a process of network monitoring, but with the development of applications on the network such as the p2p file sharing, VoIP, encrypted, and many applications that already use the same port, it would require a system that can classify network traffics, not only based on port number classification. This paper reports the implementation of the deep packet inspection method to analyse data packets based on the packet header and payload to be used in packet data classification. If each application can be grouped based on the application layer, then we can determine the pattern of internet users and also to perform network management of computer science department. In this study, a prototype wireless network and applications SSO were developed to detect the active user. The focus is on the ability of open DPI and nDPI in detecting the payload of an application and the results are elaborated in this paper.

  20. Advanced Software Development Workstation Project, phase 3

    Science.gov (United States)

    1991-01-01

    ACCESS provides a generic capability to develop software information system applications which are explicitly intended to facilitate software reuse. In addition, it provides the capability to retrofit existing large applications with a user friendly front end for preparation of input streams in a way that will reduce required training time, improve the productivity even of experienced users, and increase accuracy. Current and past work shows that ACCESS will be scalable to much larger object bases.

  1. A cycling workstation to facilitate physical activity in office settings.

    Science.gov (United States)

    Elmer, Steven J; Martin, James C

    2014-07-01

    Facilitating physical activity during the workday may help desk-bound workers reduce risks associated with sedentary behavior. We 1) evaluated the efficacy of a cycling workstation to increase energy expenditure while performing a typing task and 2) fabricated a power measurement system to determine the accuracy and reliability of an exercise cycle. Ten individuals performed 10 min trials of sitting while typing (SIT type) and pedaling while typing (PED type). Expired gases were recorded and typing performance was assessed. Metabolic cost during PED type was ∼ 2.5 × greater compared to SIT type (255 ± 14 vs. 100 ± 11 kcal h(-1), P workstation can facilitate physical activity without compromising typing performance. The exercise cycle's inaccuracy could be misleading to users. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  2. Migrating the CERN PS control system to IBM workstations

    CERN Document Server

    De Metz-Noblat, N

    1995-01-01

    The workstations used within the control system of the CERN PS accelerator complex are not produced any more. We had therefore to review the software primary used as user interface and we achieved a port to IBM workstations. We are also preparing the maintenance of this code for the next ten years with minimal staff. This implies a clear separation between general computing facilities, control system developments, and operation. In order to share our experience, we will try to summarize various aspects of this migration: - system installation principles used to speed-up error recovery time and long-term maintenance costs, - problems correlated with the coexistence of two different platforms during migration, - software problems due to the platform and operating system changes, - hidden dependencies from a specific manufacturer.

  3. ISDN communication: Its workstation technology and application system

    Energy Technology Data Exchange (ETDEWEB)

    Sugimura, T.; Ogiwara, Y.; Saito, T. (Hitachi, Ltd., Tokyo (Japan))

    1991-07-01

    This report describes technology for integrated services digital network (ISDN) which allows workstations to process multimedia data and application systems of advanced group teleworking which use such technology. Hitachi has developed workstations which are more powerful, have more functions, and have larger memory capacities. These factors allowed media which require high-speed processing of large quantities of voice and image data to be integrated into the world of conventional text data processing and communications. In addition, the application of group teleworking system has a large impact through the improvements in the office environment, the changes in the style of office work, and the appearance of new businesses. A prototype of this system was exhibited and demonstrated at TELECOM91. 1 ref., 4 figs., 2 tabs.

  4. Psychoacoustic Music Analysis Based on the Discrete Wavelet Packet Transform

    Directory of Open Access Journals (Sweden)

    Xing He

    2008-01-01

    Full Text Available Psychoacoustical computational models are necessary for the perceptual processing of acoustic signals and have contributed significantly in the development of highly efficient audio analysis and coding. In this paper, we present an approach for the psychoacoustic analysis of musical signals based on the discrete wavelet packet transform. The proposed method mimics the multiresolution properties of the human ear closer than other techniques and it includes simultaneous and temporal auditory masking. Experimental results show that this method provides better masking capabilities and it reduces the signal-to-masking ratio substantially more than other approaches, without introducing audible distortion. This model can lead to greater audio compression by permitting further bit rate reduction and more secure watermarking by providing greater signal space for information hiding.

  5. Wavelet Packet based Detection of Surface Faults on Compact Discs

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob; Wickerhauser, Mladen Victor

    2006-01-01

    In this paper the detection of faults on the surface of a compact disc is addressed. Surface faults like scratches and fingerprints disturb the on-line measurement of the pick-up position relative to the track. This is critical since the pick-up is focused on and tracked at the information track...... based on these measurements. A precise detection of the surface fault is a prerequisite to a correct handling of the faults in order to protect the pick-up of the compact disc player from audible track losses. The actual fault handling which is addressed in other publications can be carried out...... by the use of dedicated filters adapted to remove the faults from the measurements. In this paper detection using wavelet packet filters is demonstrated. The filters are designed using the joint best basis method. Detection using these filters shows a distinct improvement compared to detection using ordinary...

  6. Functionalized 2PP structures for the BioPhotonics Workstation

    DEFF Research Database (Denmark)

    Matsuoka, Tomoyo; Nishi, Masayuki; Sakakura, Masaaki

    2011-01-01

    In its standard version, our BioPhotonics Workstation (BWS) can generate multiple controllable counter-propagating beams to create real-time user-programmable optical traps for stable three-dimensional control and manipulation of a plurality of particles. The combination of the platform with micr...... on the BWS platform by functionalizing them with silica-based sol-gel materials inside which dyes can be entrapped....

  7. Improvement of the Display Design for Upgraded HANARO Operator Workstations

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Sang Hoon; Jung, H. S.; Kim, Y. K.; Choi, Y. S.; Choi, H. Y.; Kim, S. J.; In, W. H.

    2007-12-15

    While the existed HANARO Operator-Workstation(OWS) system was upgraded, the display design of OWS was modified altogether and improved more familiarly to operators according to the newly applied style-guide. It was verified that this upgraded system was reliably compatible with the existed Human-Machine Interface(HMI) surroundings and the improved points comparing before were described as newly designed OWS displays were divided by each functions

  8. ARCIMBOLDO_LITE: single-workstation implementation and use.

    Science.gov (United States)

    Sammito, Massimo; Millán, Claudia; Frieske, Dawid; Rodríguez-Freire, Eloy; Borges, Rafael J; Usón, Isabel

    2015-09-01

    ARCIMBOLDO solves the phase problem at resolutions of around 2 Å or better through massive combination of small fragments and density modification. For complex structures, this imposes a need for a powerful grid where calculations can be distributed, but for structures with up to 200 amino acids in the asymmetric unit a single workstation may suffice. The use and performance of the single-workstation implementation, ARCIMBOLDO_LITE, on a pool of test structures with 40-120 amino acids and resolutions between 0.54 and 2.2 Å is described. Inbuilt polyalanine helices and iron cofactors are used as search fragments. ARCIMBOLDO_BORGES can also run on a single workstation to solve structures in this test set using precomputed libraries of local folds. The results of this study have been incorporated into an automated, resolution- and hardware-dependent parameterization. ARCIMBOLDO has been thoroughly rewritten and three binaries are now available: ARCIMBOLDO_LITE, ARCIMBOLDO_SHREDDER and ARCIMBOLDO_BORGES. The programs and libraries can be downloaded from http://chango.ibmb.csic.es/ARCIMBOLDO_LITE.

  9. Energy-efficiency based classification of the manufacturing workstation

    Science.gov (United States)

    Frumuşanu, G.; Afteni, C.; Badea, N.; Epureanu, A.

    2017-08-01

    EU Directive 92/75/EC established for the first time an energy consumption labelling scheme, further implemented by several other directives. As consequence, nowadays many products (e.g. home appliances, tyres, light bulbs, houses) have an EU Energy Label when offered for sale or rent. Several energy consumption models of manufacturing equipments have been also developed. This paper proposes an energy efficiency - based classification of the manufacturing workstation, aiming to characterize its energetic behaviour. The concept of energy efficiency of the manufacturing workstation is defined. On this base, a classification methodology has been developed. It refers to specific criteria and their evaluation modalities, together to the definition & delimitation of energy efficiency classes. The energy class position is defined after the amount of energy needed by the workstation in the middle point of its operating domain, while its extension is determined by the value of the first coefficient from the Taylor series that approximates the dependence between the energy consume and the chosen parameter of the working regime. The main domain of interest for this classification looks to be the optimization of the manufacturing activities planning and programming. A case-study regarding an actual lathe classification from energy efficiency point of view, based on two different approaches (analytical and numerical) is also included.

  10. Energy consumption of personal computer workstations

    Energy Technology Data Exchange (ETDEWEB)

    Szydlowski, R.F.; Chvala, W.D. Jr.

    1994-02-01

    The explosive growth of the information age has had a profound effect on the appearance of today`s office. Although the telephone still remains an important part of the information exchange and processing system within an office, other electronic devices are now considered required equipment within this environment. This office automation equipment includes facsimile machines, photocopiers, personal computers, printers, modems, and other peripherals. A recent estimate of the installed base indicated that 42 million personal computers and 7.3 million printers are in place, consuming 18.2 billion kWh/yr-and this installed base is growing (Luhn 1992). From a productivity standpoint, it can be argued that this equipment greatly improves the efficiency of those working in the office. But of primary concern to energy system designers, building managers, and electric utilities is the fact that this equipment requires electric energy. Although the impact of each incremental piece of equipment is small, installation of thousands of devices per building has resulted in office automation equipment becoming the major contributor to electric consumption and demand growth in commercial buildings. Personal computers and associated equipment are the dominant part of office automation equipment. In some cases, this electric demand growth has caused office buildings electric and cooling systems to overload.

  11. Wave-packet dynamics in quantum wells

    DEFF Research Database (Denmark)

    Kuznetsov, A. V.; Sanders, G. D.; Stanton, C. J.

    1995-01-01

    It has been recently recognized that in bulk semiconductors the displacement current caused by ultrafast optical generation of ''polarized pairs'' in the applied de field is an important mechanism of charge transport in addition to the usual transport current. In quantum-well systems, this polari......It has been recently recognized that in bulk semiconductors the displacement current caused by ultrafast optical generation of ''polarized pairs'' in the applied de field is an important mechanism of charge transport in addition to the usual transport current. In quantum-well systems......, this polarized pair creation is thought to be the only source of photocurrent at the early stages of photoexcitation since the bulk like transport current is inhibited by the barriers. In this work we perform a full quantum-mechanical analysis of ultrafast optical excitation in a de-biased quantum well. We take...... into account the multiple transitions that become allowed in the de field which breaks the Delta n = 0 selection rule. As a result, the carriers are created as wave packets formed by coherent superposition of several eigenstates. When the characteristic size of these wave packets (coherence length) is much...

  12. Trabecular bone remodelling simulated by a stochastic exchange of discrete bone packets from the surface.

    Science.gov (United States)

    Hartmann, M A; Dunlop, J W C; Bréchet, Y J M; Fratzl, P; Weinkamer, R

    2011-08-01

    Human bone is constantly renewed through life via the process of bone remodelling, in which individual packets of bone are removed by osteoclasts and replaced by osteoblasts. Remodelling is mechanically controlled, where osteocytes embedded within the bone matrix are thought to act as mechanical sensors. In this computational work, a stochastic model for bone remodelling is used in which the renewal of bone material occurs by exchange of discrete bone packets. We tested different hypotheses of how the mechanical stimulus for bone remodelling is integrated by osteocytes and sent to actor cells on the bone's surface. A collective (summed) signal from multiple osteocytes as opposed to an individual (maximal) signal from a single osteocyte was found to lead to lower inner porosity and surface roughness of the simulated bone structure. This observation can be interpreted in that collective osteocyte signalling provides an effective surface tension to the remodelling process. Furthermore, the material heterogeneity due to remodelling was studied on a network of trabeculae. As the model is discrete, the age of individual bone packets can be monitored with time. The simulation results were compared with experimental data coming from quantitative back scattered electron imaging by transforming the information about the age of the bone packet into a mineral content. Discrepancies with experiments indicate that osteoclasts preferentially resorb low mineralized, i.e. young, bone at the bone's surface. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Bilateral Waveform Similarity Overlap-and-Add Based Packet Loss Concealment for Voice over IP

    Directory of Open Access Journals (Sweden)

    J.F. Yeh

    2013-08-01

    Full Text Available This paper invested a bilateral waveform similarity overlap-and-add algorithm for voice packet lost. Since Packet lost will cause the semantic misunderstanding, it has become one of the most essential problems in speech communication. This investment is based on waveform similarity measure using overlap-and-Add algorithm and provides the bilateral information to enhance the speech signal reconstruction. Traditionally, it has been improved that waveform similarity overlap-and-add (WSOLA technique is an effective algorithm to deal with packet loss concealment (PLC for real-time time communication. WSOLA algorithm is widely applied to deal with the length adaptation and packet loss concealment of speech signal. Time scale modification of audio signal is one of the most essential research topics in data communication, especially in voice of IP (VoIP. Herein, the proposed the bilateral WSOLA (BWSOLA that is derived from WSOLA. Instead of only exploitation one direction speech data, the proposed method will reconstruct the lost voice data according to the preceding and cascading data. The related algorithms have been developed to achieve the optimal reconstructing estimation. The experimental results show that the quality of the reconstructed speech signal of the bilateral WSOLA is much better compared to the standard WSOLA and GWSOLA on different packet loss rate and length using the metrics PESQ and MOS. The significant improvement is obtained by bilateral information and proposed method. The proposed bilateral waveform similarity overlap-and-add (BWSOLA outperforms the traditional approaches especially in the long duration data loss.

  14. MacPharmacy: A Relational Database Adjunt to a Hypermedia-Based Physician Workstation

    Science.gov (United States)

    Michael, Patricia A.; Foxlee, R. Heath

    1990-01-01

    MacPharmacy is a relational database built as an adjunct to RadOnc, a hypermedia-based physician workstation in the domain of radiation oncology. Conceived originally as a RadOnc module for chemotherapeutic agents, the MacPharmacy database contains information on a large selection of drugs which can be accessed by a variety of users. Information on generic and trade names, pharmacodynamics, indications, and dosage is linked to RadOnc disease descriptions and patient records which contain a clinical summary of the presentation, treatment and results. MacPharmacy's features include data table addition and updating and a customizable user interface that can be linked to other applications. Due to the scarcity of Macintosh-based pharmacy databases, MacPharmacy fills an information gap for clinically-oriented Macintosh users.

  15. All-optical devices for ultrafast packet switching

    DEFF Research Database (Denmark)

    Dorren, H.J.S.; HerreraDorren, J.; Raz, O.

    2007-01-01

    We discuss integrated devices for all-optical packet switching. We focus on monolithically integrated all-optical flip-flops, ultra-fast semiconductor based wavelength converters and explain the operation principles. Finally, a 160 Gb/s all-optical packet switching experiment over 110 km of field...

  16. Wave Packet Propagation and Electric Conductivity of Nanowires

    NARCIS (Netherlands)

    Maeda, Munehiko; Saito, Keiji; Miyashita, Seiji; Raedt, Hans De

    2004-01-01

    We compute the electric conductivity of nanowires in the presence of magnetic domain walls by the method of wave packet propagation. We demonstrate that the propagation through the wire depends on the initial state used in the wave packet simulation. We propose a procedure, based on the Landauer

  17. Packet throughput performance of multiservice, multirate OCDMA in elastic networks

    DEFF Research Database (Denmark)

    Raddo, Thiago R.; Sanches, Anderson L.; Tafur Monroy, Idelfonso

    2016-01-01

    In this paper, the packet throughput performance of multiservice, multirate optical code-division multiple-access (OCDMA) networks is addressed based on two distinct multirate techniques, namely multilength code and multicode. A new analytical formalism to evaluate the packet throughput performance...

  18. Wave packet construction in three-dimensional quantum billiards ...

    Indian Academy of Sciences (India)

    Wave packet construction in three-dimensional quantum billiards: Visualizing the closed orbit, collapse and revival of wave packets in the cubical billiard ... billiard and these levels disappear completely or partially for a parallelepiped billiard as the symmetry breaks due to commensurate or incommensurate ratio of sides.

  19. Manifestations of wave packet revivals in the moments of observables

    Science.gov (United States)

    Sudheesh, C.; Lakshmibala, S.; Balakrishnan, V.

    2004-08-01

    Using a generic Hamiltonian that models wave packet propagation in a Kerr-like medium, matter wave field dynamics in Bose-Einstein condensation, etc., we show that distinctive signatures of wave packet revivals and fractional revivals are displayed by the time evolution of the expectation values of appropriate observables, enabling selective identification of different fractional revivals.

  20. Accounting Clerk Guide, Test Packet--Part I.

    Science.gov (United States)

    Foster, Brian; And Others

    The test packet is part of an eight volume unit for grades 10, 11, and 12, designed for individualized progression in preparing students for entry into the occupation of accounting clerk. The test packet contains both pretests and post-tests for lessons 1 through 12. The unit is concerned with the basic accounting theory found in the accounting…

  1. 41 CFR 101-39.306 - Operator's packet.

    Science.gov (United States)

    2010-07-01

    ...-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.3-Use and Care of GSA Interagency Fleet Management System Vehicles § 101-39.306 Operator's packet. The GSA Interagency Fleet Management System (IFMS) will provide each... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Operator's packet. 101-39...

  2. Controlling the spreading of wave packets of a dissociating molecule

    DEFF Research Database (Denmark)

    Tiwari, Ashwani Kumar; Møller, Klaus Braagaard; Henriksen, Niels Engholm

    2007-01-01

    A first-order perturbation theoretic approach within the electric-dipole approximation is used to study the time evolution of wave packets created by linearly chirped laser pulses on a repulsive potential of Br-2. Our calculations show that negatively chirped pulses focus the wave packet in the F...

  3. Packet Delay Variation Analysis of the CQ Switch

    Directory of Open Access Journals (Sweden)

    I. Radusinović

    2012-06-01

    Full Text Available Packet delay variation analysis for a 32x32 crosspoint queued switch under uniform and IBP arrival traffic is presented in this paper. Different buffer sizes and several scheduling algorithms are observed: longest queue first, round robin, exhaustive round robin and frame based round robin matching. Results show that the least packet delay variation, among observed algorithms, causes round robin algorithm.

  4. Analytic and rule-based decision support tool for VDT workstation adjustment and computer accessories arrangement.

    Science.gov (United States)

    Rurkhamet, Busagarin; Nanthavanij, Suebsak

    2004-12-01

    One important factor that leads to the development of musculoskeletal disorders (MSD) and cumulative trauma disorders (CTD) among visual display terminal (VDT) users is their work posture. While operating a VDT, a user's body posture is strongly influenced by the task, VDT workstation settings, and layout of computer accessories. This paper presents an analytic and rule-based decision support tool called EQ-DeX (an ergonomics and quantitative design expert system) that is developed to provide valid and practical recommendations regarding the adjustment of a VDT workstation and the arrangement of computer accessories. The paper explains the structure and components of EQ-DeX, input data, rules, and adjustment and arrangement algorithms. From input information such as gender, age, body height, task, etc., EQ-DeX uses analytic and rule-based algorithms to estimate quantitative settings of a computer table and a chair, as well as locations of computer accessories such as monitor, document holder, keyboard, and mouse. With the input and output screens that are designed using the concept of usability, the interactions between the user and EQ-DeX are convenient. Examples are also presented to demonstrate the recommendations generated by EQ-DeX.

  5. A digital photogrammetric workstation on the WEB

    Science.gov (United States)

    Drap, P.; Grussenmeyer, P.

    The main features of a WEB-based tool for digital architectural photogrammetry called Architectural Photogrammetry Network Tool for Education and Research (ARPENTEUR) are presented. The aim of this project is to propose a photogrammetric software package made freely available on the Internet as an applet through a simple browser ( http://www.arpenteur.net). All the photogrammetric adjustment and image processing classes are written in Java™. The use of large applets in photogrammetry has not been very advanced until now but rate transfers and compatibility levels of Internet browsers will increase in the near future. Users can set up their own projects by transferring their images, camera, and control information on the ARPENTEUR servers from any place in the world connected on the Internet. Various examples of small format architectural photogrammetry projects are also accessible via WWW and can be used for teaching. This software is an extension of the Traitement d'Images et Photogrammétrie Numérique (TIPHON) software developed at ENSAIS-LERGEC. The photogrammetric model is currently computed by the traditional steps of inner, relative and absolute orientations. The measurements in the images can be performed manually or by image correlation. The measured points, lines, and geometrical primitives are recorded in text files and visualised inside a standard WEB browser. The plotting module is especially dedicated to architectural surveys and based on a formalisation of architectural and geometrical knowledge. The latest developments of the Java programming language and object-oriented systems are used in ARPENTEUR, both in the photogrammetric and in the architectural part, and ensure a high level of compatibility with any hardware platform supporting a WEB browser.

  6. A Modular, Scalable, Extensible, and Transparent Optical Packet Buffer

    Science.gov (United States)

    Small, Benjamin A.; Shacham, Assaf; Bergman, Keren

    2007-04-01

    We introduce a novel optical packet switching buffer architecture that is composed of multiple building-block modules, allowing for a large degree of scalability. The buffer supports independent and simultaneous read and write processes without packet rejection or misordering and can be considered a fully functional packet buffer. It can easily be programmed to support two prioritization schemes: first-in first-out (FIFO) and last-in first-out (LIFO). Because the system leverages semiconductor optical amplifiers as switching elements, wideband packets can be routed transparently. The operation of the system is discussed with illustrative packet sequences, which are then verified on an actual implementation composed of conventional fiber-optic componentry.

  7. Scheduling Issues in ECOFRAME Optical Packet Switched Ring

    Directory of Open Access Journals (Sweden)

    P. Gravey

    2011-06-01

    Full Text Available In the metropolitan area, traditional SONET/SDH circuit switched rings are likely to be replaced with optical packet/burst switching technologies. In this paper we consider a slotted WDM optical packet ring operating without resource reservation mechanisms. In such rings, optical packets in transit have priority over traffic to be inserted by the node. Packets to be inserted are thus queued according to their destination, in order to avoid headof-line blocking. We focus on scheduling policies and compare several MaxWeight scheduling policies, including Oldest Packet First (OPF which emulates FIFO queueing while avoiding head-of-line blocking. We show that there is a trade-off between implementation complexity and fairness, and identify the Largest Virtual Waiting Time First (LVWTF scheduling policy as presenting both a low complexity and a good fairness performance.

  8. Poisson Packet Traffic Generation Based on Empirical Data

    Directory of Open Access Journals (Sweden)

    Andrej Kos

    2003-10-01

    Full Text Available An algorithm for generating equivalent Poisson packet traffic based on empirical traffic data is presented in this paper. Two steps are required in order to produce equivalent Poisson packet traffic. Real traffic trace is analyzed in the first step. In the second step, a new equivalent synthetic Poisson traffic is generated in such a way that the first order statistical parameters remain unchanged. New packet inter-arrival time series are produced in a random manner using negative exponential probability distribution with a known mean. New packet size series are also produced in a random manner. However, due to specified minimum and maximum packet sizes, a truncated exponential probability distribution is applied.

  9. A design study investigating augmented reality and photograph annotation in a digitalized grossing workstation

    Directory of Open Access Journals (Sweden)

    Joyce A Chow

    2017-01-01

    Full Text Available Context: Within digital pathology, digitalization of the grossing procedure has been relatively underexplored in comparison to digitalization of pathology slides. Aims: Our investigation focuses on the interaction design of an augmented reality gross pathology workstation and refining the interface so that information and visualizations are easily recorded and displayed in a thoughtful view. Settings and Design: The work in this project occurred in two phases: the first phase focused on implementation of an augmented reality grossing workstation prototype while the second phase focused on the implementation of an incremental prototype in parallel with a deeper design study. Subjects and Methods: Our research institute focused on an experimental and “designerly” approach to create a digital gross pathology prototype as opposed to focusing on developing a system for immediate clinical deployment. Statistical Analysis Used: Evaluation has not been limited to user tests and interviews, but rather key insights were uncovered through design methods such as “rapid ethnography” and “conversation with materials”. Results: We developed an augmented reality enhanced digital grossing station prototype to assist pathology technicians in capturing data during examination. The prototype uses a magnetically tracked scalpel to annotate planned cuts and dimensions onto photographs taken of the work surface. This article focuses on the use of qualitative design methods to evaluate and refine the prototype. Our aims were to build on the strengths of the prototype's technology, improve the ergonomics of the digital/physical workstation by considering numerous alternative design directions, and to consider the effects of digitalization on personnel and the pathology diagnostics information flow from a wider perspective. A proposed interface design allows the pathology technician to place images in relation to its orientation, annotate directly on the

  10. A Design Study Investigating Augmented Reality and Photograph Annotation in a Digitalized Grossing Workstation.

    Science.gov (United States)

    Chow, Joyce A; Törnros, Martin E; Waltersson, Marie; Richard, Helen; Kusoffsky, Madeleine; Lundström, Claes F; Kurti, Arianit

    2017-01-01

    Within digital pathology, digitalization of the grossing procedure has been relatively underexplored in comparison to digitalization of pathology slides. Our investigation focuses on the interaction design of an augmented reality gross pathology workstation and refining the interface so that information and visualizations are easily recorded and displayed in a thoughtful view. The work in this project occurred in two phases: the first phase focused on implementation of an augmented reality grossing workstation prototype while the second phase focused on the implementation of an incremental prototype in parallel with a deeper design study. Our research institute focused on an experimental and "designerly" approach to create a digital gross pathology prototype as opposed to focusing on developing a system for immediate clinical deployment. Evaluation has not been limited to user tests and interviews, but rather key insights were uncovered through design methods such as "rapid ethnography" and "conversation with materials". We developed an augmented reality enhanced digital grossing station prototype to assist pathology technicians in capturing data during examination. The prototype uses a magnetically tracked scalpel to annotate planned cuts and dimensions onto photographs taken of the work surface. This article focuses on the use of qualitative design methods to evaluate and refine the prototype. Our aims were to build on the strengths of the prototype's technology, improve the ergonomics of the digital/physical workstation by considering numerous alternative design directions, and to consider the effects of digitalization on personnel and the pathology diagnostics information flow from a wider perspective. A proposed interface design allows the pathology technician to place images in relation to its orientation, annotate directly on the image, and create linked information. The augmented reality magnetically tracked scalpel reduces tool switching though limitations

  11. Waveform and packet structure of lion roars

    Directory of Open Access Journals (Sweden)

    W. Baumjohann

    Full Text Available The Equator-S magnetometer is very sensitive and has a sampling rate of normally 128 Hz. The high sampling rate allows for the first time fluxgate magnetometer measurements of ELF waves between the ion cyclotron and the lower hybrid frequencies in the equatorial dayside magnetosheath. The so-called lion roars, typically seen by the Equator-S magnetometer at the bottom of the magnetic troughs of magnetosheath mirror waves, are near-monochromatic packets of electron whistler waves lasting for a few wave cycles only, typically 0.25 s. They are right-hand circularly polarized waves with typical amplitudes of 0.5–1 nT at around one tenth of the electron gyrofrequency. The cone angle between wave vector and ambient field is usually smaller than 1.5°.

    Key words. Interplanetary physics (MHD waves and turbulence; plasma waves and turbulence

  12. Data Aggregation and Packet Bundling of Uplink Small Packets for Monitoring Applications in LTE

    DEFF Research Database (Denmark)

    Kim, Dong Min; Sørensen, René Brandborg; Mahmood, Kashif

    2017-01-01

    In cellular massive machine-type communications, a device can transmit directly to the BS or through an aggregator (intermediate node). While direct device-BS communication has recently been the focus of 5G/3GPP research and standardization efforts, the use of aggregators remains a less explored ...... of aggregators and packet bundle size. Our results show that, in general, data aggregation can benefit the uplink massive MTC in LTE by reducing the signaling overhead....

  13. A study of artificial speech quality assessors of VoIP calls subject to limited bursty packet losses

    Directory of Open Access Journals (Sweden)

    Jelassi Sofiene

    2011-01-01

    Full Text Available Abstract A revolutionary feature of emerging media services over the Internet is their ability to account for human perception during service delivery processes, which surely increases their popularity and incomes. In such a situation, it is necessary to understand the users' perception, what should obviously be done using standardized subjective experiences. However, it is also important to develop artificial quality assessors that enable to automatically quantify the perceived quality. This efficiently helps performing optimal network and service management at the core and edges of the delivery systems. In our article, we explore the behavior rating of new emerging artificial speech quality assessors of VoIP calls subject to moderately bursty packet loss processes. The examined Speech Quality Assessment (SQA algorithms are able to estimate speech quality of live VoIP calls at run-time using control information extracted from header content of received packets. They are especially designed to be sensitive to packet loss burstiness. The performance evaluation study is performed using a dedicated set-up software-based SQA framework. It offers a specialized packet killer and includes the implementation of four SQA algorithms. A speech quality database, which covers a wide range of bursty packet loss conditions, has been created and then thoroughly analyzed. Our main findings are the following: (1 all examined automatic bursty-loss aware speech quality assessors achieve a satisfactory correlation under upper (> 20% and lower (< 10% ranges of packet loss processes; (2 they exhibit a clear weakness to assess speech quality under a moderated packet loss process; (3 the accuracy of sequence-by-sequence basis of examined SQA algorithms should be addressed in detail for further precision.

  14. The effect of a sit-stand workstation intervention on daily sitting, standing and physical activity: protocol for a 12 month workplace randomised control trial.

    Science.gov (United States)

    Hall, Jennifer; Mansfield, Louise; Kay, Tess; McConnell, Alison K

    2015-02-15

    A lack of physical activity and excessive sitting can contribute to poor physical health and wellbeing. The high percentage of the UK adult population in employment, and the prolonged sitting associated with desk-based office-work, make these workplaces an appropriate setting for interventions to reduce sedentary behaviour and increase physical activity. This pilot study aims to determine the effect of an office-based sit-stand workstation intervention, compared with usual desk use, on daily sitting, standing and physical activity, and to examine the factors that underlie sitting, standing and physical activity, within and outside, the workplace. A randomised control trial (RCT) comparing the effects of a sit-stand workstation only and a multi-component sit-stand workstation intervention, with usual desk-based working practice (no sit-stand workstation) will be conducted with office workers across two organisations, over a 12 month period (N = 30). The multicomponent intervention will comprise organisational, environmental and individual elements. Objective data will be collected at baseline, and after 2-weeks, 3-months, 6-months and 12-months of the intervention. Objective measures of sitting, standing, and physical activity will be made concurrently (ActivPAL3™ and ActiGraph (GT3X+)). Activity diaries, ethnographic participant observation, and interviews with participants and key organisational personnel will be used to elicit understanding of the influence of organisational culture on sitting, standing and physical activity behaviour in the workplace. This study will be the first long-term sit-stand workstation intervention study utilising an RCT design, and incorporating a comprehensive process evaluation. The study will generate an understanding of the factors that encourage and restrict successful implementation of sit-stand workstation interventions, and will help inform future occupational wellbeing policy and practice. Other strengths include the

  15. Entanglement of molecular-orientation, rotational and orbital degrees of freedom in multiphoton orientational wave packets

    Energy Technology Data Exchange (ETDEWEB)

    Mainos, C; Dutier, G; Grucker, J; Perales, F; Baudon, J; Ducloy, M [Laboratoire de Physique des Lasers, Universite Paris 13 Av JB Clement, 93430 Villetaneuse (France)

    2008-02-14

    Multiphoton orientational wave packets induced by short resonant polarized laser pulses in a rotationally-frozen interacting molecule contain relevant information. The entanglement of the orbital, rotational and orientational degrees of freedom shows a strong dependence on the polarization state of the absorbed photons and the space orientation of the interacting molecule and enables one to assign the orbital state of the excited molecular electron, to measure the space orientation of the interacting molecule from the orientational recurrences, to relate the measured temporal widths to the angular momentum photon state and the coherence of the laser pulse, to obtain information on the ground rotational state, or to measure the effective temperature of an isotropic molecular assembly. The space orientation of a small number of independent molecules can be distinguished from their distinct orientational dependence in the formation of the individual orientational wave packets.

  16. Entanglement of molecular-orientation, rotational and orbital degrees of freedom in multiphoton orientational wave packets

    Science.gov (United States)

    Mainos, C.; Dutier, G.; Grucker, J.; Perales, F.; Baudon, J.; Ducloy, M.

    2008-02-01

    Multiphoton orientational wave packets induced by short resonant polarized laser pulses in a rotationally-frozen interacting molecule contain relevant information. The entanglement of the orbital, rotational and orientational degrees of freedom shows a strong dependence on the polarization state of the absorbed photons and the space orientation of the interacting molecule and enables one to assign the orbital state of the excited molecular electron, to measure the space orientation of the interacting molecule from the orientational recurrences, to relate the measured temporal widths to the angular momentum photon state and the coherence of the laser pulse, to obtain information on the ground rotational state, or to measure the effective temperature of an isotropic molecular assembly. The space orientation of a small number of independent molecules can be distinguished from their distinct orientational dependence in the formation of the individual orientational wave packets.

  17. The benefits of EVAR planning using a 3D workstation.

    Science.gov (United States)

    Sobocinski, J; Chenorhokian, H; Maurel, B; Midulla, M; Hertault, A; Le Roux, M; Azzaoui, R; Haulon, S

    2013-10-01

    To evaluate the influence of planning endovascular aneurysm repair (EVAR) with a three-dimensional (3D) workstation on early and midterm outcomes. All patients undergoing infrarenal EVAR performed between 2006 and 2009 at our institution were included in the current study. Prior to 2008 (group 1), endograft sizing was performed by interrogation of computed tomography angiography axial images. After 2008 (group 2), endograft sizing was routinely performed using a 3D workstation (Aquarius, Terarecon), allowing for multiplanar reconstruction and centerline analysis. Pre-, peri-, postoperative, and follow-up data were prospectively entered in an electronic database. All postoperative complications and subsequent secondary interventions depicted during the 2-year period following EVAR were compared. Secondary intervention and mortality rates were defined at 2 years and compared. Freedom from secondary intervention and overall survival rates were calculated using the Kaplan-Meier method during follow-up and compared by log-rank test. A total of 295 patients (149 patients in group 1 and 146 patients in group 2) were included. All patients had completed a minimum of 2 years of follow-up. During this 2-year period following EVAR, the type 1 endoleak rate was 8.7% in group 1 and 1.4% in group 2 (p = .004) respectively. Secondary intervention rates related to type 1 endoleak was 5.4% in group 1 and 0 in group 2 (p workstations for EVAR planning significantly reduces the rate of type 1 endoleaks and, therefore, the rate of related secondary interventions. Copyright © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  18. Clinical impact and value of workstation single sign-on.

    Science.gov (United States)

    Gellert, George A; Crouch, John F; Gibson, Lynn A; Conklin, George S; Webster, S Luke; Gillean, John A

    2017-05-01

    CHRISTUS Health began implementation of computer workstation single sign-on (SSO) in 2015. SSO technology utilizes a badge reader placed at each workstation where clinicians swipe or "tap" their identification badges. To assess the impact of SSO implementation in reducing clinician time logging in to various clinical software programs, and in financial savings from migrating to a thin client that enabled replacement of traditional hard drive computer workstations. Following implementation of SSO, a total of 65,202 logins were sampled systematically during a 7day period among 2256 active clinical end users for time saved in 6 facilities when compared to pre-implementation. Dollar values were assigned to the time saved by 3 groups of clinical end users: physicians, nurses and ancillary service providers. The reduction of total clinician login time over the 7day period showed a net gain of 168.3h per week of clinician time - 28.1h (2.3 shifts) per facility per week. Annualized, 1461.2h of mixed physician and nursing time is liberated per facility per annum (121.8 shifts of 12h per year). The annual dollar cost savings of this reduction of time expended logging in is $92,146 per hospital per annum and $1,658,745 per annum in the first phase implementation of 18 hospitals. Computer hardware equipment savings due to desktop virtualization increases annual savings to $2,333,745. Qualitative value contributions to clinician satisfaction, reduction in staff turnover, facilitation of adoption of EHR applications, and other benefits of SSO are discussed. SSO had a positive impact on clinician efficiency and productivity in the 6 hospitals evaluated, and is an effective and cost-effective method to liberate clinician time from repetitive and time consuming logins to clinical software applications. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  19. An Imaging And Graphics Workstation For Image Sequence Analysis

    Science.gov (United States)

    Mostafavi, Hassan

    1990-01-01

    This paper describes an application-specific engineering workstation designed and developed to analyze imagery sequences from a variety of sources. The system combines the software and hardware environment of the modern graphic-oriented workstations with the digital image acquisition, processing and display techniques. The objective is to achieve automation and high throughput for many data reduction tasks involving metric studies of image sequences. The applications of such an automated data reduction tool include analysis of the trajectory and attitude of aircraft, missile, stores and other flying objects in various flight regimes including launch and separation as well as regular flight maneuvers. The workstation can also be used in an on-line or off-line mode to study three-dimensional motion of aircraft models in simulated flight conditions such as wind tunnels. The system's key features are: 1) Acquisition and storage of image sequences by digitizing real-time video or frames from a film strip; 2) computer-controlled movie loop playback, slow motion and freeze frame display combined with digital image sharpening, noise reduction, contrast enhancement and interactive image magnification; 3) multiple leading edge tracking in addition to object centroids at up to 60 fields per second from both live input video or a stored image sequence; 4) automatic and manual field-of-view and spatial calibration; 5) image sequence data base generation and management, including the measurement data products; 6) off-line analysis software for trajectory plotting and statistical analysis; 7) model-based estimation and tracking of object attitude angles; and 8) interface to a variety of video players and film transport sub-systems.

  20. JPL multipolarization workstation - Hardware, software and examples of data analysis

    Science.gov (United States)

    Burnette, Fred; Norikane, Lynne

    1987-01-01

    A low-cost stand-alone interactive image processing workstation has been developed for operations on multipolarization JPL aircraft SAR data, as well as data from future spaceborne imaging radars. A recently developed data compression technique is used to reduce the data volume to 10 Mbytes, for a typical data set, so that interactive analysis may be accomplished in a timely and efficient manner on a supermicrocomputer. In addition to presenting a hardware description of the work station, attention is given to the software that has been developed. Three illustrative examples of data analysis are presented.

  1. Evaluating biomechanics of user-selected sitting and standing computer workstation.

    Science.gov (United States)

    Lin, Michael Y; Barbir, Ana; Dennerlein, Jack T

    2017-11-01

    A standing computer workstation has now become a popular modern work place intervention to reduce sedentary behavior at work. However, user's interaction related to a standing computer workstation and its differences with a sitting workstation need to be understood to assist in developing recommendations for use and set up. The study compared the differences in upper extremity posture and muscle activity between user-selected sitting and standing workstation setups. Twenty participants (10 females, 10 males) volunteered for the study. 3-D posture, surface electromyography, and user-reported discomfort were measured while completing simulated tasks with each participant's self-selected workstation setups. Sitting computer workstation associated with more non-neutral shoulder postures and greater shoulder muscle activity, while standing computer workstation induced greater wrist adduction angle and greater extensor carpi radialis muscle activity. Sitting computer workstation also associated with greater shoulder abduction postural variation (90th-10th percentile) while standing computer workstation associated with greater variation for should rotation and wrist extension. Users reported similar overall discomfort levels within the first 10 min of work but had more than twice as much discomfort while standing than sitting after 45 min; with most discomfort reported in the low back for standing and shoulder for sitting. These different measures provide understanding in users' different interactions with sitting and standing and by alternating between the two configurations in short bouts may be a way of changing the loading pattern on the upper extremity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Observation of Quantum Interference between Separated Mechanical Oscillator Wave Packets.

    Science.gov (United States)

    Kienzler, D; Flühmann, C; Negnevitsky, V; Lo, H-Y; Marinelli, M; Nadlinger, D; Home, J P

    2016-04-08

    We directly observe the quantum interference between two well-separated trapped-ion mechanical oscillator wave packets. The superposed state is created from a spin-motion entangled state using a heralded measurement. Wave packet interference is observed through the energy eigenstate populations. We reconstruct the Wigner function of these states by introducing probe Hamiltonians which measure Fock state populations in displaced and squeezed bases. Squeezed-basis measurements with 8 dB squeezing allow the measurement of interference for Δα=15.6, corresponding to a distance of 240 nm between the two superposed wave packets.

  3. SDRAM-based packet buffer model for high speed switches

    DEFF Research Database (Denmark)

    Rasmussen, Anders; Ruepp, Sarah Renée; Berger, Michael Stübert

    2011-01-01

    This article investigates the how the performance of SDRAM based packet buffering systems for high performance switches can be simulated using OPNET. In order to include the access pattern dependent performance of SDRAM modules in simulations, a custom SDRAM model is implemented in OPNET Modeller...... based on the specifications of a real-life DDR3-SDRAM chip. Based on this model the performance of different schemes for optimizing the performance of such a packet buffer can be evaluated. The purpose of this study is to find efficient schemes for memory mapping of the packet queues and I/O traffic...

  4. JACK - ANTHROPOMETRIC MODELING SYSTEM FOR SILICON GRAPHICS WORKSTATIONS

    Science.gov (United States)

    Smith, B.

    1994-01-01

    JACK is an interactive graphics program developed at the University of Pennsylvania that displays and manipulates articulated geometric figures. JACK is typically used to observe how a human mannequin interacts with its environment and what effects body types will have upon the performance of a task in a simulated environment. Any environment can be created, and any number of mannequins can be placed anywhere in that environment. JACK includes facilities to construct limited geometric objects, position figures, perform a variety of analyses on the figures, describe the motion of the figures and specify lighting and surface property information for rendering high quality images. JACK is supplied with a variety of body types pre-defined and known to the system. There are both male and female bodies, ranging from the 5th to the 95th percentile, based on NASA Standard 3000. Each mannequin is fully articulated and reflects the joint limitations of a normal human. JACK is an editor for manipulating previously defined objects known as "Peabody" objects. Used to describe the figures as well as the internal data structure for representing them, Peabody is a language with a powerful and flexible mechanism for representing connectivity between objects, both the joints between individual segments within a figure and arbitrary connections between different figures. Peabody objects are generally comprised of several individual figures, each one a collection of segments. Each segment has a geometry represented by PSURF files that consist of polygons or curved surface patches. Although JACK does not have the capability to create new objects, objects may be created by other geometric modeling programs and then translated into the PSURF format. Environment files are a collection of figures and attributes that may be dynamically moved under the control of an animation file. The animation facilities allow the user to create a sequence of commands that duplicate the movements of a

  5. Asynchronous broadcast for ordered delivery between compute nodes in a parallel computing system where packet header space is limited

    Science.gov (United States)

    Kumar, Sameer

    2010-06-15

    Disclosed is a mechanism on receiving processors in a parallel computing system for providing order to data packets received from a broadcast call and to distinguish data packets received at nodes from several incoming asynchronous broadcast messages where header space is limited. In the present invention, processors at lower leafs of a tree do not need to obtain a broadcast message by directly accessing the data in a root processor's buffer. Instead, each subsequent intermediate node's rank id information is squeezed into the software header of packet headers. In turn, the entire broadcast message is not transferred from the root processor to each processor in a communicator but instead is replicated on several intermediate nodes which then replicated the message to nodes in lower leafs. Hence, the intermediate compute nodes become "virtual root compute nodes" for the purpose of replicating the broadcast message to lower levels of a tree.

  6. Accessible microscopy workstation for students and scientists with mobility impairments.

    Science.gov (United States)

    Duerstock, Bradley S

    2006-01-01

    An integrated accessible microscopy workstation was designed and developed to allow persons with mobility impairments to control all aspects of light microscopy with minimal human assistance. This system, named AccessScope, is capable of performing brightfield and fluorescence microscopy, image analysis, and tissue morphometry requisite for undergraduate science courses to graduate-level research. An accessible microscope is necessary for students and scientists with mobility impairments to be able to use a microscope independently to better understand microscopical imaging concepts and cell biology. This knowledge is not always apparent by simply viewing a catalog of histological images. The ability to operate a microscope independently eliminates the need to hire an assistant or rely on a classmate and permits one to take practical laboratory examinations by oneself. Independent microscope handling is also crucial for graduate students and scientists with disabilities to perform scientific research. By making a personal computer as the user interface for controlling AccessScope functions, different upper limb mobility impairments could be accommodated by using various computer input devices and assistive technology software. Participants with a range of upper limb mobility impairments evaluated the prototype microscopy workstation. They were able to control all microscopy functions including loading different slides without assistance.

  7. Biomek Cell Workstation: A Variable System for Automated Cell Cultivation.

    Science.gov (United States)

    Lehmann, R; Severitt, J C; Roddelkopf, T; Junginger, S; Thurow, K

    2016-06-01

    Automated cell cultivation is an important tool for simplifying routine laboratory work. Automated methods are independent of skill levels and daily constitution of laboratory staff in combination with a constant quality and performance of the methods. The Biomek Cell Workstation was configured as a flexible and compatible system. The modified Biomek Cell Workstation enables the cultivation of adherent and suspension cells. Until now, no commercially available systems enabled the automated handling of both types of cells in one system. In particular, the automated cultivation of suspension cells in this form has not been published. The cell counts and viabilities were nonsignificantly decreased for cells cultivated in AutoFlasks in automated handling. The proliferation of manual and automated bioscreening by the WST-1 assay showed a nonsignificant lower proliferation of automatically disseminated cells associated with a mostly lower standard error. The disseminated suspension cell lines showed different pronounced proliferations in descending order, starting with Jurkat cells followed by SEM, Molt4, and RS4 cells having the lowest proliferation. In this respect, we successfully disseminated and screened suspension cells in an automated way. The automated cultivation and dissemination of a variety of suspension cells can replace the manual method. © 2015 Society for Laboratory Automation and Screening.

  8. Design and Development of an Integrated Workstation Automation Hub

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Andrew; Ghatikar, Girish; Sartor, Dale; Lanzisera, Steven

    2015-03-30

    Miscellaneous Electronic Loads (MELs) account for one third of all electricity consumption in U.S. commercial buildings, and are drivers for a significant energy use in India. Many of the MEL-specific plug-load devices are concentrated at workstations in offices. The use of intelligence, and integrated controls and communications at the workstation for an Office Automation Hub – offers the opportunity to improve both energy efficiency and occupant comfort, along with services for Smart Grid operations. Software and hardware solutions are available from a wide array of vendors for the different components, but an integrated system with interoperable communications is yet to be developed and deployed. In this study, we propose system- and component-level specifications for the Office Automation Hub, their functions, and a prioritized list for the design of a proof-of-concept system. Leveraging the strength of both the U.S. and India technology sectors, this specification serves as a guide for researchers and industry in both countries to support the development, testing, and evaluation of a prototype product. Further evaluation of such integrated technologies for performance and cost is necessary to identify the potential to reduce energy consumptions in MELs and to improve occupant comfort.

  9. Texture analysis software: integration with a radiological workstation.

    Science.gov (United States)

    Duvauferrier, Régis; Bezy, Joan; Bertaud, Valérie; Toussaint, Grégoire; Morelli, John; Lasbleiz, Jeremy

    2012-01-01

    Image analysis is the daily task of radiologists. The texture of a structure or imaging finding can be more difficult to describe than other parameters. Image processing can help the radiologist in completing this difficult task. The aim of this article is to explain how we have developed texture analysis software and integrated it into a standard radiological workstation. The texture analysis method has been divided into three steps: definition of primitive elements, counting, and statistical analysis. The software was developed in C++ and integrated into a Siemens workstation with a graphical user interface. The results of analyses may be exported in Excel format. The software allows users to perform texture analyses on any type of radiological image without the need for image transfer by simply placing a region of interest. This tool has already been used to assess the trabecular network of vertebra. The integration of such software into PACS extends the applicability of texture analysis beyond that of a mere research tool and facilitates its use in routine clinical practice.

  10. Image sequence analysis workstation for multipoint motion analysis

    Science.gov (United States)

    Mostafavi, Hassan

    1990-08-01

    This paper describes an application-specific engineering workstation designed and developed to analyze motion of objects from video sequences. The system combines the software and hardware environment of a modem graphic-oriented workstation with the digital image acquisition, processing and display techniques. In addition to automation and Increase In throughput of data reduction tasks, the objective of the system Is to provide less invasive methods of measurement by offering the ability to track objects that are more complex than reflective markers. Grey level Image processing and spatial/temporal adaptation of the processing parameters is used for location and tracking of more complex features of objects under uncontrolled lighting and background conditions. The applications of such an automated and noninvasive measurement tool include analysis of the trajectory and attitude of rigid bodies such as human limbs, robots, aircraft in flight, etc. The system's key features are: 1) Acquisition and storage of Image sequences by digitizing and storing real-time video; 2) computer-controlled movie loop playback, freeze frame display, and digital Image enhancement; 3) multiple leading edge tracking in addition to object centroids at up to 60 fields per second from both live input video or a stored Image sequence; 4) model-based estimation and tracking of the six degrees of freedom of a rigid body: 5) field-of-view and spatial calibration: 6) Image sequence and measurement data base management; and 7) offline analysis software for trajectory plotting and statistical analysis.

  11. A prospective study on the user-friendliness of four anaesthesia workstations.

    Science.gov (United States)

    Pouzeratte, Y; Sebbane, M; Jung, B; Delay, J-M; Eliet, J; Eledjam, J-J; Capdevila, X; Jaber, S

    2008-08-01

    Unlike for intensive care unit and home mechanical ventilators, no study has evaluated the user-friendliness of the recently introduced new anaesthesia workstations. We performed a prospective study to evaluate the user-friendliness of four anaesthesia workstations, which were categorized into two groups: first-generation (Kion) and second-generation (Avance, Felix and Primus). Twenty users (12 nurse-anaesthetists and 8 anaesthesiologists) from three different anaesthesia departments at the same univeristy hospital participated in the study. The user-friendliness scale evaluated 10 criteria, including two design and monitoring criteria, four maintenance criteria and four ventilation use criteria. Each criterion was evaluated from 0 (poor) to 10 (excellent). The mean score obtained for the first-generation workstation was lower than those obtained for the three second-generation workstations (P < 0.05). No significant differences in the overall user-friendliness score was observed for the three second-generation workstations. The first-generation workstation obtained a significantly lower score than the three second-generation workstations for the design criteria (P < 0.01). For the screen criteria, the highest score was obtained by Felix, which has the largest screen and associated characters. For the main maintenance criteria, Kion and Felix obtained the lowest scores. No significant differences between the four anaesthesia workstations were found for only three of the user-friendliness criteria (self-test, alarms and settings). Anaesthesia machines have benefited from considerable advances in design and technology. This novel user-friendliness scale revealed that the most recent workstations were more appreciated by users than the first-generation of anaesthesia workstations. This user-friendliness scale may help the anaesthetic staff to 'consensually' choose the future workstation for their anaesthesia department.

  12. Local Surface Reconstruction from MER images using Stereo Workstation

    Science.gov (United States)

    Shin, Dongjoe; Muller, Jan-Peter

    2010-05-01

    The authors present a semi-automatic workflow that reconstructs the 3D shape of the martian surface from local stereo images delivered by PnCam or NavCam on systems such as the NASA Mars Exploration Rover (MER) Mission and in the future the ESA-NASA ExoMars rover PanCam. The process is initiated with manually selected tiepoints on a stereo workstation which is then followed by a tiepoint refinement, stereo-matching using region growing and Levenberg-Marquardt Algorithm (LMA)-based bundle adjustment processing. The stereo workstation, which is being developed by UCL in collaboration with colleagues at the Jet Propulsion Laboratory (JPL) within the EU FP7 ProVisG project, includes a set of practical GUI-based tools that enable an operator to define a visually correct tiepoint via a stereo display. To achieve platform and graphic hardware independence, the stereo application has been implemented using JPL's JADIS graphic library which is written in JAVA and the remaining processing blocks used in the reconstruction workflow have also been developed as a JAVA package to increase the code re-usability, portability and compatibility. Although initial tiepoints from the stereo workstation are reasonably acceptable as true correspondences, it is often required to employ an optional validity check and/or quality enhancing process. To meet this requirement, the workflow has been designed to include a tiepoint refinement process based on the Adaptive Least Square Correlation (ALSC) matching algorithm so that the initial tiepoints can be further enhanced to sub-pixel precision or rejected if they fail to pass the ALSC matching threshold. Apart from the accuracy of reconstruction, it is obvious that the other criterion to assess the quality of reconstruction is the density (or completeness) of reconstruction, which is not attained in the refinement process. Thus, we re-implemented a stereo region growing process, which is a core matching algorithm within the UCL

  13. Throughput and Delay Performance Analysis of Packet Aggregation Scheme for PRMA

    DEFF Research Database (Denmark)

    Zhang, Qi; Iversen, Villy Bæk; Fitzek, Frank H.P.

    2008-01-01

    , the system throughput depends on the size of packets and the number of consecutive packets. From the statistics of existent wireless data networks using PRMA protocol, it shows that the system throughput is quite low because of the inconsecutive small packets. In order to improve the throughput, packet...

  14. Extraction of state-to-state reactive scattering attributes from wave packet in reactant Jacobi coordinates.

    Science.gov (United States)

    Sun, Zhigang; Guo, Hua; Zhang, Dong H

    2010-02-28

    The S-matrix for a scattering system provides the most detailed information about the dynamics. In this work, we discuss the calculation of S-matrix elements for the A+BC-->AB+C, AC+B type reaction. Two methods for extracting S-matrix elements from a single wave packet in reactant Jacobi coordinates are reviewed and compared. Both methods are capable of extracting the state-to-state attributes for both product channels from a single wave packet propagation. It is shown through the examples of H+HD, Cl+H(2), and H+HCl reactions that such reactant coordinate based methods are easy to implement, numerically efficient, and accurate. Additional efficiency can be gained by the use of a L-shaped grid with two-dimensional fast Fourier transform.

  15. Some Results on the Wavelet Packet Decomposition of Nonstationary Processes

    Directory of Open Access Journals (Sweden)

    Sami Touati

    2002-11-01

    Full Text Available Wavelet/wavelet packet decomposition has become a very useful tool in describing nonstationary processes. Important examples of nonstationary processes encountered in practice are cyclostationary processes or almost-cyclostationary processes. In this paper, we study the statistical properties of the wavelet packet decomposition of a large class of nonstationary processes, including in particular cyclostationary and almost-cyclostationary processes. We first investigate in a general framework, the existence and some properties of the cumulants of wavelet packet coefficients. We then study more precisely the almost-cyclostationary case, and determine the asymptotic distributions of wavelet packet coefficients. Finally, we particularize some of our results in the cyclostationary case before providing some illustrative simulations.

  16. GALILEO JUPITER PLASMA RAW PACKETIZED TELEMETRY V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains instrument packet files (IPFs) from the Plasma Science experiment (PLS) onboard the Galileo spacecraft during the Jupiter orbital operations...

  17. Resonance-Assisted Decay of Nondispersive Wave Packets

    OpenAIRE

    Wimberger, S.; Schlagheck, P.; Eltschka, C.; Buchleitner, A.

    2006-01-01

    We present a quantitative semiclassical theory for the decay of nondispersive electronic wave packets in driven, ionizing Rydberg systems. Statistically robust quantities are extracted combining resonance assisted tunneling with subsequent transport across chaotic phase space and a final ionization step.

  18. Further Results on Extended Delivery Time for Secondary Packet Transmission

    KAUST Repository

    Usman, Muneer

    2017-07-10

    Cognitive radio transceiver can opportunistically access the underutilized spectrum resource of primary systems for new wireless services. With interweave cognitive implementation, secondary transmission may be interrupted by primary transmission. To facilitate the packet delay analysis of such secondary transmission, we study the extended delivery time of secondary packet transmission. In particular, we derive the exact distribution function of extended delivery time of a fixed-size secondary packet with non-work-preserving strategy, where interrupted packets must be repeated. We also analyze the effect of imperfect periodic sensing, i.e., the secondary user periodically senses the spectrum for availability, with a chance of missing an available channel on a certain sensing attempt. These results complement previous work on work-preserving strategy with perfect sensing. Selected numerical and simulation results are presented for verifying the mathematical formulation.

  19. Massachusetts Bay - Internal wave packets digitized from SAR imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This feature class contains internal wave packets digitized from SAR imagery at 1:350,000 scale in Massachusetts Bay. Internal waves are nonsinusoidal waves that...

  20. LG based decision aid for naval tactical action officer's (TAO) workstation

    Science.gov (United States)

    Stilman, Boris; Yakhnis, Vladimir; Umanskiy, Oleg; Boyd, Ron

    2005-05-01

    In the increasingly NetCentric battlespace of the 21st century, Stilman Advanced Strategies Linguistic Geometry software has the potential to revolutionize the way that the Navy fights in two key areas: as a Tactical Decision Aid and for creating a relevant Common Operating Picture. Incorporating STILMAN's software into a prototype Tactical Action Officers (TAO) workstation as a Tactical Decision Aid (TDA) will allow warfighters to manage their assets more intelligently and effectively. This prototype workstation will be developed using human-centered design principles and will be an open, component-based architecture for combat control systems for future small surface combatants. It will integrate both uninhabited vehicles and onboard sensors and weapon systems across a squadron of small surface combatants. In addition, the hypergame representation of complex operations provides a paradigm for the presentation of a common operating picture to operators and personnel throughout the command hierarchy. In the hypergame technology there are game levels that span the range from the tactical to the global strategy level, with each level informing the others. This same principle will be applied to presenting the relevant common operating picture to operators. Each operator will receive a common operating picture that is appropriate for their level in the command hierarchy. The area covered by this operating picture and the level of detail contained within it will be dependent upon the specific tasks the operator is performing (supervisory vice tactical control) and the level of the operator (or command personnel) within the command hierarchy. Each level will inform the others to keep the picture concurrent and up-to-date.

  1. Label-controlled optical packet routing technologies and applications

    DEFF Research Database (Denmark)

    Koonen, A.M.J.; Yan, N.; Vegas Olmos, Juan José

    2007-01-01

    An overview is given of various optical packet labeling techniques. The architecture and technologies are discussed for optical packet routing nodes using orthogonal labeling with optoelectronic label processing, and for nodes using time-serial labeling with all-optical time-serial label processing....... An example of a nearterm application is given, and a comparison of routing technologies is made regarding their cost and reliability aspects....

  2. On wave-packet dynamics in a decaying quadratic potential

    DEFF Research Database (Denmark)

    Møller, Klaus Braagaard; Henriksen, Niels Engholm

    1997-01-01

    We consider the time-dependent Schrodinger equation for a quadratic potential with an exponentially decaying force constant. General analytical solutions are presented and we highlight in particular, the signatures of classical mechanics in the wave packet dynamics.......We consider the time-dependent Schrodinger equation for a quadratic potential with an exponentially decaying force constant. General analytical solutions are presented and we highlight in particular, the signatures of classical mechanics in the wave packet dynamics....

  3. Optical packet networks - conclusions from the IST DAVID project

    DEFF Research Database (Denmark)

    Dittmann, Lars

    2004-01-01

    This work outlines the result from the European research project DAVID working with optical packet switch solutions for both WAN and MAN. The project started July 2000 and has been completed successfully by the end of 2003.......This work outlines the result from the European research project DAVID working with optical packet switch solutions for both WAN and MAN. The project started July 2000 and has been completed successfully by the end of 2003....

  4. Priority-based methods for reducing the impact of packet loss on HEVC encoded video streams

    Science.gov (United States)

    Nightingale, James; Wang, Qi; Grecos, Christos

    2013-02-01

    The rapid growth in the use of video streaming over IP networks has outstripped the rate at which new network infrastructure has been deployed. These bandwidth-hungry applications now comprise a significant part of all Internet traffic and present major challenges for network service providers. The situation is more acute in mobile networks where the available bandwidth is often limited. Work towards the standardisation of High Efficiency Video Coding (HEVC), the next generation video coding scheme, is currently on track for completion in 2013. HEVC offers the prospect of a 50% improvement in compression over the current H.264 Advanced Video Coding standard (H.264/AVC) for the same quality. However, there has been very little published research on HEVC streaming or the challenges of delivering HEVC streams in resource-constrained network environments. In this paper we consider the problem of adapting an HEVC encoded video stream to meet the bandwidth limitation in a mobile networks environment. Video sequences were encoded using the Test Model under Consideration (TMuC HM6) for HEVC. Network abstraction layers (NAL) units were packetized, on a one NAL unit per RTP packet basis, and transmitted over a realistic hybrid wired/wireless testbed configured with dynamically changing network path conditions and multiple independent network paths from the streamer to the client. Two different schemes for the prioritisation of RTP packets, based on the NAL units they contain, have been implemented and empirically compared using a range of video sequences, encoder configurations, bandwidths and network topologies. In the first prioritisation method the importance of an RTP packet was determined by the type of picture and the temporal switching point information carried in the NAL unit header. Packets containing parameter set NAL units and video coding layer (VCL) NAL units of the instantaneous decoder refresh (IDR) and the clean random access (CRA) pictures were given the

  5. Semiautomated DNA Mutation Analysis Using a Robotic Workstation and Molecular Beacons

    National Research Council Canada - National Science Library

    Smit, Maarten L; Giesendorf, Belinda A.J; Vet, Jacqueline A.M; Trijbels, Frans J.M; Blom, Henk J

    2001-01-01

    .... Because of new DNA extraction procedures based on DNA-binding magnetic beads, centrifugation can be eliminated and implementation in robotic pipetting workstations can be performed. The use of a robotic pipetting workstation and magnetic beads (1-3) will not only reduce total handling and processing time, but will also eliminate the risk for sample intercha...

  6. Combining Workstation Design and Performance Management to Increase Ergonomically Correct Computer Typing Postures

    Science.gov (United States)

    Culig, Kathryn M.; Dickinson, Alyce M.; Lindstrom-Hazel, Debra; Austin, John

    2008-01-01

    The effects of workstation changes and a performance management (PM) package on seven typing postures were examined for seven office workers. Workstation adjustments were implemented first. Two participants increased five safe postures by 50% or more. The effects of a PM package on postures that did not improve by 50% were then examined using a…

  7. An architecture for an integrated medical workstation : its realization and evaluation

    NARCIS (Netherlands)

    E.M. van Mulligen (Erik)

    1993-01-01

    textabstractThis study describes the development of the HERMES integrated medical workstation for the support of patient care and clinical data analysis. Tbis development proceeded in two steps. First, a prototype integrated workstation was developed for the limited domain of support for clinical

  8. The effect of dynamic workstations on the performance of various computer and office-based tasks

    NARCIS (Netherlands)

    Burford, E.M.; Botter, J.; Commissaris, D.; Könemann, R.; Hiemstra-Van Mastrigt, S.; Ellegast, R.P.

    2013-01-01

    The effect of different workstations, conventional and dynamic, on different types of performance measures for several different office and computer based task was investigated in this research paper. The two dynamic workstations assessed were the Lifespan Treadmill Desk and the RightAngle

  9. Effects of a standing and three dynamic workstations on computer task performance and cognitive function tests

    NARCIS (Netherlands)

    Commissaris, D.A.C.M.; Könemann, R.; Hiemstra-van Mastrigt, S.; Burford, E.M.; Botter, J.; Douwes, M.; Ellegast, R.P.

    2014-01-01

    Sedentary work entails health risks. Dynamic (or active) workstations, at which computer tasks can be combined with physical activity, may reduce the risks of sedentary behaviour. The aim of this study was to evaluate short term task performance while working on three dynamic workstations: a

  10. TCP Packet Trace Analysis. M.S. Thesis

    Science.gov (United States)

    Shepard, Timothy J.

    1991-01-01

    Examination of a trace of packets collected from the network is often the only method available for diagnosing protocol performance problems in computer networks. This thesis explores the use of packet traces to diagnose performance problems of the transport protocol TCP. Unfortunately, manual examination of these traces can be so tedious that effective analysis is not possible. The primary contribution of this thesis is a graphical method of displaying the packet trace which greatly reduce, the tediousness of examining a packet trace. The graphical method is demonstrated by the examination of some packet traces of typical TCP connections. The performance of two different implementations of TCP sending data across a particular network path is compared. Traces many thousands of packets long are used to demonstrate how effectively the graphical method simplifies examination of long complicated traces. In the comparison of the two TCP implementations, the burstiness of the TCP transmitter appeared to be related to the achieved throughput. A method of quantifying this burstiness is presented and its possible relevance to understanding the performance of TCP is discussed.

  11. DESIGN OF AN ARRAYED WAVEGUIDE GRATINGS BASED OPTICAL PACKET SWITCH

    Directory of Open Access Journals (Sweden)

    VAIBHAV SHUKLA

    2016-12-01

    Full Text Available Optical packet switching is considered as the future of data transfer technologyin combination with middle-aged electronics. The biggest challenge encountered in optical packet switching is the lack of optical buffers for storing the contending packets. Therefore, for the contention resolution of packets, a temporary storage in terms of fiber delay lines is used. This task is accomplished by an optical packet switch. In this paper, a design modification in the AWGR (Arrayed Waveguide Grating Router is presented for improving the switch performance. The power budget analysis of the switch is also presented to estimate the sufficient power level of the switch. The obtained results clearly reveal that the architecture presented in this paper can be operated in micro-watts in comparison to the earlier optical switch which operates in milli watts regime. Finally, simulation results are presented to obtain packet loss probability and average delay. Even at the higher load of 0.6, the switch presented in this paper provides a very low loss probability (10^6 and delay remain within 2 slots.

  12. Disinfection of the Radiologist Workstation and Radiologist Hand Hygiene: A Single Institution Practice Quality Improvement Project.

    Science.gov (United States)

    Quon, Jeffrey S; Dilauro, Marc; Ryan, John G

    2017-08-01

    The purpose of this study was to evaluate the workstation disinfection rates and hand hygiene of radiologists and trainees at shared departmental workstations and assess the impact of education and reminder placards on daily habits. A 10-question survey was administered to all staff radiologists, fellows, and residents at our institution. The questions pertained to workstation disinfection, hand hygiene habits, and accessibility to disinfectant wipes and hand sanitizer stations. Subsequently, a short educational PowerPoint presentation was emailed to the department and small reminder placards were placed at each workstation. A follow-up survey was administered. Chi-square and Wilcoxon signed-rank tests were used to analyse the results. The percentage of participants who disinfect their workstations 1-2 times/week, 3-4 times/week or everyday increased from 53.4% (45 of 84 participants) to 74.3% (55 of 74 participants; P = .01), while the number who disinfect their workstation workstation increased from 41.6% (35 of 84 participants) to 48.7% (36 of 74 participants; P = .76) and hand washing after working at the workstation increased from 50.0% (42 of 84 participants) to 56.8% (42 of 74 participants; P = .49). At our institution, the implementation of daily reminder placards at each workstation and the administration of an educational PowerPoint presentation improved the rate of radiologist workstation disinfection. Copyright © 2016 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

  13. Combining control electronics with SOA to equalize packet-to-packet power variations for optical 3R regeneration in optical networks at 10 Gbit/s

    DEFF Research Database (Denmark)

    Wessing, Henrik; Lavigne, B.; Sørensen, Brian Michael

    2004-01-01

    We report on the combined effects of control electronics and a SOA as to suppress packet to packet power fluctuations. Associated to a SOA-MZI based 3R regenerator, we demonstrate a power dynamic range of 9 dB.......We report on the combined effects of control electronics and a SOA as to suppress packet to packet power fluctuations. Associated to a SOA-MZI based 3R regenerator, we demonstrate a power dynamic range of 9 dB....

  14. Construction of a Dual-Tip Scanning Tunneling Microscope: a Prototype Nanotechnology Workstation.

    Science.gov (United States)

    Voelker, Mark Alan

    1993-01-01

    This dissertation describes the construction and performance of a dual-tip scanning tunneling microscope (STM). The microscope was built as a prototype nanotechnology workstation, a general purpose instrument designed to give a researcher the ability to investigate and manipulate nanometer scale structures. Chapter One describes the genesis and development of the concept of nanotechnology, from the atomic hypothesis of Democritus to modern developments in synthetic chemistry. Nanometer scale electronics (molecular electronics) is introduced and the state of the art in this field is described. The dual-tip scanning probe microscope is proposed as a way to address individual molecular electronic devices, a key goal in realizing nanometer scale electronic technology. Investigation of microtubules, a proposed nanometer scale intracellular biological information processing system, is also discussed. Chapter Two reviews the history and fundamental physics of STM, along with the related techniques of Field Ion Microscopy (FIM) and Ballistic Electon Emission Microscopy (BEEM). BEEM is used to introduce the physics of the dual -tip STM. Other dual-probe systems are also described. Chapter Three covers the design and construction of the dual-tip STM. Both hardware and software are described in detail. Chapter Four presents the results obtained with the dual-tip STM, including dual-tip images and noise measurements for the electronic circuitry. The last chapter, Chapter Five, contains suggested design changes for improving the performance of the dual -tip microscope and descriptions of experiments that can be performed with an improved instrument. Design and use of a nanotechnology workstation in the fields of semiconductor electronics, molecular electronics and cellular biology is discussed. Investigation of neurons grown on a silicon chip with a dual-tip STM system is proposed. Four Appendices present a noise model of the STM tunneling gap and preamplifier, describe

  15. Ergonomic assessment of selected workstations on a merchant ship.

    Science.gov (United States)

    Krystosik-Gromadzińska, Agata

    2018-03-01

    This study describes some key ergonomic factors within the engine room, navigation bridge and other locations of a merchant ship. Ergonomic assessments were carried out on a crew of a merchant ship. The study examines the importance of factors such as noise, vibration, heat radiation (in machinery areas), psychological stress and ergonomics of the physical arrangement of the navigation bridge. It also addresses the effect of working in confined areas for a long duration and the need to process large amounts of data, decision-making and the influence of specific operating conditions in different areas of a ship. This study includes analysis of workstations, working methods and the burden of environmental factors as well as a discussion of specific marine environmental conditions such as confined working and leisure spaces, long-term family and sociocultural separation, frequent changes in climate and time zones, and temporary physical overload and long-term psychological burdens.

  16. Advanced Operator Workstation Display Design for a User Interface

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Sang-Hoon; Jung, Hoan-Sung; Choi, Young-San; Kim, Young-Ki; Kim, Hyung-Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2007-10-15

    The HANARO operator workstation in the main control room that continuously controls and monitors the overall reactor condition is being upgraded in various directions to catch up with the demand from operators. But the original design of OWS has some difficulties in the implementation of a more sophisticated system due to the poor software configuration that has a limitation in its hardware performance. Such hardware restrictions as the resolution problem, system performance, and a utility which is behind the times result in retarding development of the OWS display design. But with hardware progress a more comprehensive control system can be realized and it satisfies more requirements with a high specification. It is demonstrated in this paper that the applied functions are shown through a remarkable example of a display.

  17. VDU workstations and vision in post office and bank operators.

    Science.gov (United States)

    Tebboune, Cheikh El-Bachir; Mebarki, Bouhafs

    2012-01-01

    A cross-sectional study was carried out on a sample of 26 VDU operators in a post office and a bank, working regularly on video display units. The study aimed at (1) determining the physical working conditions, particularly lighting conditions, (2) assessing employees' complaints, (3) measuring visual defects among operators in VDU workstations. The following results are revealed: (a) ergonomic shortcomings in workplace and work station design were clearly noticed (b) noise level was between 60 db and 78 db, (c) illumination parameters did not much the task and caused ocular symptoms and visual fatigue, (d) visual tests revealed vision defects in 84.6% of the cases, (e) visual fatigue was noticed at the end of the working day. The abnormal frequency of operators' complaints can be explained by the association of visual defects and inadequate working conditions.

  18. The importance of an ergonomic workstation to practicing sonographers.

    Science.gov (United States)

    Baker, Joan P; Coffin, Carolyn T

    2013-08-01

    Musculoskeletal disorders have been described in a number of professions over the years. They are defined as injuries that are caused by or aggravated by workplace activities, and they account for up to 60% of all workplace illnesses. They are known by different names, such as musculoskeletal disorder, repetitive strain injury, cumulative trauma disorder, and repetitive motion injury. Musculoskeletal disorders have only been identified in sonographers since 1997 but are increasing in incidence. Surveys done among American and Canadian sonographers in 1997 showed an 84% incidence; however, this incidence had increased to 90% by 2008. Understanding the importance of optimal body mechanics and how to maintain neutral postures will enable sonographers to reduce the risk factors associated with their profession. Even with the most advanced equipment, an ergonomic workstation is only as effective as the person using it.

  19. A workstation based simulator for teaching compressible aerodynamics

    Science.gov (United States)

    Benson, Thomas J.

    1994-01-01

    A workstation-based interactive flow simulator has been developed to aid in the teaching of undergraduate compressible aerodynamics. By solving the equations found in NACA 1135, the simulator models three basic fluids problems encountered in supersonic flow: flow past a compression corner, flow past two wedges in series, and flow past two opposed wedges. The study can vary the geometry or flow conditions through a graphical user interface and the new conditions are calculated immediately. Various graphical formats present the results of the flow calculations to the student. The simulator includes interactive questions and answers to aid in both the use of the tool and to develop an understanding of some of the complexities of compressible aerodynamics. A series of help screens make the simulator easy to learn and use.

  20. Advanced software development workstation project: Engineering scripting language. Graphical editor

    Science.gov (United States)

    1992-01-01

    Software development is widely considered to be a bottleneck in the development of complex systems, both in terms of development and in terms of maintenance of deployed systems. Cost of software development and maintenance can also be very high. One approach to reducing costs and relieving this bottleneck is increasing the reuse of software designs and software components. A method for achieving such reuse is a software parts composition system. Such a system consists of a language for modeling software parts and their interfaces, a catalog of existing parts, an editor for combining parts, and a code generator that takes a specification and generates code for that application in the target language. The Advanced Software Development Workstation is intended to be an expert system shell designed to provide the capabilities of a software part composition system.

  1. Adaptive Conflict-Free Optimization of Rule Sets for Network Security Packet Filtering Devices

    Directory of Open Access Journals (Sweden)

    Andrea Baiocchi

    2015-01-01

    Full Text Available Packet filtering and processing rules management in firewalls and security gateways has become commonplace in increasingly complex networks. On one side there is a need to maintain the logic of high level policies, which requires administrators to implement and update a large amount of filtering rules while keeping them conflict-free, that is, avoiding security inconsistencies. On the other side, traffic adaptive optimization of large rule lists is useful for general purpose computers used as filtering devices, without specific designed hardware, to face growing link speeds and to harden filtering devices against DoS and DDoS attacks. Our work joins the two issues in an innovative way and defines a traffic adaptive algorithm to find conflict-free optimized rule sets, by relying on information gathered with traffic logs. The proposed approach suits current technology architectures and exploits available features, like traffic log databases, to minimize the impact of ACO development on the packet filtering devices. We demonstrate the benefit entailed by the proposed algorithm through measurements on a test bed made up of real-life, commercial packet filtering devices.

  2. Detection of Pathological and Normal Heartbeat Using Wavelet Packet, Support Vector Machines and Multilayer Perceptron

    Directory of Open Access Journals (Sweden)

    Alejandro J. Orozco-Naranjo

    2013-11-01

    Full Text Available This paper presents the results obtained by developing a methodology to detect 5 types of heartbeats (Normal (N, Right bundle branch block (RBBB, Left bundle branch block (LBBB, Premature atrial contraction (APC and Premature ventricular contraction (PVC, using Wavelet transform packets with non-adaptative mode applied on features extraction from heartbeats. It was used the Shannon function to calculate the entropy and It was added an identification nodes stage per every type of cardiac signal in the Wavelet tree. The using of Wavelet packets transform allows the access to information which results of decomposition of low and high frecuency, giving providing a more integral analysis than achieved by the discrete Wavelet transform. Three families of mother Wavelet were evaluated on transformation: Daubechies, Symlet and Reverse Biorthogonal, which were results from a previous research in that were identified the mother Wavelet that had higher entropy with the cardiac signals. With non-adaptive mode, the computational cost is reduced when Wavelet packets are used; this cost represents the most marked disadvantage from the transform. To classify the heartbeats were used Support Vector Machines and Multilayer Perceptron. The best classification error was achieved employing Support Vector Machine and a radial basis function; it was 2.57 %.

  3. Modeling the spread of virus in packets on scale free network

    Science.gov (United States)

    Lamzabi, S.; Lazfi, S.; Rachadi, A.; Ez-Zahraouy, H.; Benyoussef, A.

    2016-01-01

    In this paper, we propose a new model for computer virus attacks and recovery at the level of information packets. The model we propose is based on one hand on the susceptible-infected (SI) and susceptible-infected-recovered (SIR) stochastic epidemic models for computer virus propagation and on the other hand on the time-discrete Markov chain of the minimal traffic routing protocol. We have applied this model to the scale free Barabasi-Albert network to determine how the dynamics of virus propagation is affected by the traffic flow in both the free-flow and the congested phases. The numerical results show essentially that the proportion of infected and recovered packets increases when the rate of infection λ and the recovery rate β increase in the free-flow phase while in the congested phase, the number of infected (recovered) packets presents a maximum (minimum) at certain critical value of β characterizing a certain competition between the infection and the recovery rates.

  4. Transitioning Newborns from NICU to Home: Family Information Packet

    Science.gov (United States)

    ... bienestar Condiciones y enfermedades Atención médica Medicamentos La seguridad del paciente Calidad de atención médica Healthcare Delivery ... Research Trust Fund News Newsroom Press Releases AHRQ Social Media AHRQ Stats Data Visualizations Impact Case Studies ...

  5. Load balancing in OCDM optical packet switched networks

    Science.gov (United States)

    Yun, Ling; Qiu, Kun; Jiang, JIhai; Li, Yanqiu

    2008-11-01

    Optical packet switching (OPS), which transfers the switching function from electrical domain to optical domain and provides the smallest switching granularity, is the most potential candidate of switching form in the future optical networks. Optical code division multiplexing (OCDM) is the mostly practical all-optical processing technology at the state of the art. The experiments of optical packet switching with optical code (OC) label have demonstrated the switching capability and advantages. But the timing of erasing and inserting label, which is similar with the bit-serial label processing, is the stringent requirement of this scheme. OCDM optical packet switching, which encodes the payload directly and removes the label when the payload is recovered at the decoder, has no stringent timing requirement. Multiple access interference (MAI) is the main factor degrading the performance of OCDM optical packet-switched networks. In this paper, the effects of MAI are studied at the end of optical label path where the packets experience multiple hops. For eliminating the end-to-end BER, the optical label paths need to be established in an optimum way and the load are required to be balanced. One load-balancing algorithm based on the end-to-end BER of OCDM path is proposed to improve the network performance.

  6. Changing the way we work: elevating energy expenditure with workstation alternatives.

    Science.gov (United States)

    Tudor-Locke, C; Schuna, J M; Frensham, L J; Proenca, M

    2014-06-01

    Emerging evidence supports the feasibility of raising daily energy expenditure (EE) by replacing office work-related sedentary behavior with low-intensity non-exercise physical activity (PA) via workstation alternatives to the traditional office chair and desktop computer-based combinations. The purpose of this review article is to introduce a simple taxonomy to facilitate classification and study of workstation alternatives, catalog the diversity of research undertaken to date related to energy balance, and present and summarize the gaps and opportunities for a research agenda for workstation alternatives moving forward. A PubMed search elicited 57 English language articles published since 2000; additional articles were identified by reviewing reference sections and contacting authors. Selection criteria ultimately focused on use of workstation alternatives during simulated or real work tasks. The EE of sitting on a stability ball or using sit-stand/standing desks is comparable to the traditional seated condition (≅1.2 kcal min(-1)). The treadmill and pedal desks (active workstation alternatives) offer the greatest promise in terms of EE (≅2-4 kcal min(-1)). Sitting on a stability ball or using sit-stand/standing desks does not impair task performance relative to the traditional seated condition. Some evidence of typing impairment is inconsistently reported with active workstation alternatives; the finer motor skills required for mouse-related tasks may be more affected. Little is known about learning or adaptation with practice. Users are generally accepting of workstation alternatives; however, there is evidence of less than optimal use. Active workstations (that is, treadmill desks and pedal desks) in particular represent a potential strategy for mitigating the diminished EE inherent to contemporary office-based workplaces, but only if they are scalable. The science supporting active workstations is young and heterogeneous; however, this means that

  7. Converting multiple OC-3c ATM streams to HIPPI to drive an HDTV frame buffer from a workstation cluster

    Energy Technology Data Exchange (ETDEWEB)

    Tolmie, D.E.; Dornhoff, A.G.; DuBois, A.J.

    1994-12-01

    A group of eight Digital Equipment Corporation Alpha workstations is interconnected with ATM to form a cluster with supercomputer power. For output, each workstation drives a single ``tile`` on an 8-tile high-resolution frame buffer. A special purpose adapter is used to convert the workstation`s ATM format to the frame buffer`s HIPPI format. This paper discusses the rationale behind the workstation farm, and then describes the visualization output path in detail. To provide the system quickly, special emphasis was placed on making the design as simple as possible. The design choices are examined, and the resultant system is described.

  8. Zoning and workstation analysis in interventional cardiology; Zonage et etude de poste en cardiologie interventionnelle

    Energy Technology Data Exchange (ETDEWEB)

    Degrange, J.P. [RP-Consult, 42 rue Pouchet, 75017 Paris (France)

    2009-07-01

    As interventional cardiology can induce high doses not only for patients but also for the personnel, the delimitation of regulated areas (or zoning) and workstation analysis (dosimetry) are very important in terms of radioprotection. This paper briefly recalls methods and tools for the different steps to perform zoning and workstation analysis. It outlines the peculiarities of interventional cardiology, presents methods and tools adapted to interventional cardiology, and then discusses the same issues but for workstation analysis. It also outlines specific problems which can be met, and their possible adapted solutions

  9. High-performance mass storage system for workstations

    Science.gov (United States)

    Chiang, T.; Tang, Y.; Gupta, L.; Cooperman, S.

    1993-01-01

    Reduced Instruction Set Computer (RISC) workstations and Personnel Computers (PC) are very popular tools for office automation, command and control, scientific analysis, database management, and many other applications. However, when using Input/Output (I/O) intensive applications, the RISC workstations and PC's are often overburdened with the tasks of collecting, staging, storing, and distributing data. Also, by using standard high-performance peripherals and storage devices, the I/O function can still be a common bottleneck process. Therefore, the high-performance mass storage system, developed by Loral AeroSys' Independent Research and Development (IR&D) engineers, can offload a RISC workstation of I/O related functions and provide high-performance I/O functions and external interfaces. The high-performance mass storage system has the capabilities to ingest high-speed real-time data, perform signal or image processing, and stage, archive, and distribute the data. This mass storage system uses a hierarchical storage structure, thus reducing the total data storage cost, while maintaining high-I/O performance. The high-performance mass storage system is a network of low-cost parallel processors and storage devices. The nodes in the network have special I/O functions such as: SCSI controller, Ethernet controller, gateway controller, RS232 controller, IEEE488 controller, and digital/analog converter. The nodes are interconnected through high-speed direct memory access links to form a network. The topology of the network is easily reconfigurable to maximize system throughput for various applications. This high-performance mass storage system takes advantage of a 'busless' architecture for maximum expandability. The mass storage system consists of magnetic disks, a WORM optical disk jukebox, and an 8mm helical scan tape to form a hierarchical storage structure. Commonly used files are kept in the magnetic disk for fast retrieval. The optical disks are used as archive

  10. Optimization and Assessment of Wavelet Packet Decompositions with Evolutionary Computation

    Directory of Open Access Journals (Sweden)

    Schell Thomas

    2003-01-01

    Full Text Available In image compression, the wavelet transformation is a state-of-the-art component. Recently, wavelet packet decomposition has received quite an interest. A popular approach for wavelet packet decomposition is the near-best-basis algorithm using nonadditive cost functions. In contrast to additive cost functions, the wavelet packet decomposition of the near-best-basis algorithm is only suboptimal. We apply methods from the field of evolutionary computation (EC to test the quality of the near-best-basis results. We observe a phenomenon: the results of the near-best-basis algorithm are inferior in terms of cost-function optimization but are superior in terms of rate/distortion performance compared to EC methods.

  11. On-board congestion control for satellite packet switching networks

    Science.gov (United States)

    Chu, Pong P.

    1991-01-01

    It is desirable to incorporate packet switching capability on-board for future communication satellites. Because of the statistical nature of packet communication, incoming traffic fluctuates and may cause congestion. Thus, it is necessary to incorporate a congestion control mechanism as part of the on-board processing to smooth and regulate the bursty traffic. Although there are extensive studies on congestion control for both baseband and broadband terrestrial networks, these schemes are not feasible for space based switching networks because of the unique characteristics of satellite link. Here, we propose a new congestion control method for on-board satellite packet switching. This scheme takes into consideration the long propagation delay in satellite link and takes advantage of the the satellite's broadcasting capability. It divides the control between the ground terminals and satellite, but distributes the primary responsibility to ground terminals and only requires minimal hardware resource on-board satellite.

  12. Foreign Material in the Gastrointestinal Tract: Cocaine Packets

    Directory of Open Access Journals (Sweden)

    Nurten Turkel Kucukmetin

    2014-01-01

    Full Text Available Smuggling drugs by swallowing or inserting into a body cavity is not only a serious and growing international crime, but can also lead to lethal medical complications. The most common cause of death in ‘body packers', people transporting drugs by ingesting a packet into the gastrointestinal tract, is acute drug toxicity from a ruptured packet. However, more than 30 years after the initial report of body packing, there is still no definitive treatment protocol for the management of this patient group. The treatment strategy is determined according to the particular condition of the patient and the clinical experience of the treatment center. Surgical intervention is also less common now, due to both the use of improved packaging materials among smugglers and a shift towards a more conservative medical approach. Herein, we report a case of toxicity from ingested packets of cocaine that leaked and, despite surgery, resulted in exitus of the patient.

  13. Packet Header Compression for the Internet of Things

    Directory of Open Access Journals (Sweden)

    Pekka KOSKELA

    2016-01-01

    Full Text Available Due to the extensive growth of Internet of Things (IoT, the number of wireless devices connected to the Internet is forecasted to grow to 26 billion units installed in 2020. This will challenge both the energy efficiency of wireless battery powered devices and the bandwidth of wireless networks. One solution for both challenges could be to utilize packet header compression. This paper reviews different packet compression, and especially packet header compression, methods and studies the performance of Robust Header Compression (ROHC in low speed radio networks such as XBEE, and in high speed radio networks such as LTE and WLAN. In all networks, the compressing and decompressing processing causes extra delay and power consumption, but in low speed networks, energy can still be saved due to the shorter transmission time.

  14. Advances in integrated photonic circuits for packet-switched interconnection

    Science.gov (United States)

    Williams, Kevin A.; Stabile, Ripalta

    2014-03-01

    Sustained increases in capacity and connectivity are needed to overcome congestion in a range of broadband communication network nodes. Packet routing and switching in the electronic domain are leading to unsustainable energy- and bandwidth-densities, motivating research into hybrid solutions: optical switching engines are introduced for massive-bandwidth data transport while the electronic domain is clocked at more modest GHz rates to manage routing. Commercially-deployed optical switching engines using MEMS technologies are unwieldy and too slow to reconfigure for future packet-based networking. Optoelectronic packet-compliant switch technologies have been demonstrated as laboratory prototypes, but they have so far mostly used discretely pigtailed components, which are impractical for control plane development and product assembly. Integrated photonics has long held the promise of reduced hardware complexity and may be the critical step towards packet-compliant optical switching engines. Recently a number of laboratories world-wide have prototyped optical switching circuits using monolithic integration technology with up to several hundreds of integrated optical components per chip. Our own work has focused on multi-input to multi-output switching matrices. Recently we have demonstrated 8×8×8λ space and wavelength selective switches using gated cyclic routers and 16×16 broadband switching chips using monolithic multi-stage networks. We now operate these advanced circuits with custom control planes implemented with FPGAs to explore real time packet routing in multi-wavelength, multi-port test-beds. We review our contributions in the context of state of the art photonic integrated circuit technology and packet optical switching hardware demonstrations.

  15. The Control Packet Collision Avoidance Algorithm for the Underwater Multichannel MAC Protocols via Time-Frequency Masking

    Directory of Open Access Journals (Sweden)

    Yang Yu

    2016-01-01

    Full Text Available Establishing high-speed and reliable underwater acoustic networks among multiunmanned underwater vehicles (UUVs is basic to realize cooperative and intelligent control among different UUVs. Nevertheless, different from terrestrial network, the propagation speed of the underwater acoustic network is 1500 m/s, which makes the design of the underwater acoustic network MAC protocols a big challenge. In accordance with multichannel MAC protocols, data packets and control packets are transferred through different channels, which lowers the adverse effect of acoustic network and gradually becomes the popular issues of underwater acoustic networks MAC protocol research. In this paper, we proposed a control packet collision avoidance algorithm utilizing time-frequency masking to deal with the control packets collision in the control channel. This algorithm is based on the scarcity of the noncoherent underwater acoustic communication signals, which regards collision avoiding as separation of the mixtures of communication signals from different nodes. We first measure the W-Disjoint Orthogonality of the MFSK signals and the simulation result demonstrates that there exists time-frequency mask which can separate the source signals from the mixture of the communication signals. Then we present a pairwise hydrophones separation system based on deep networks and the location information of the nodes. Consequently, the time-frequency mask can be estimated.

  16. Electron acceleration by Landau resonance with whistler mode wave packets

    Science.gov (United States)

    Gurnett, D. A.; Reinleitner, L. A.

    1983-01-01

    Recent observations of electrostatic waves associated with whistler mode chorus emissions provide evidence that electrons are being trapped by Landau resonance interactions with the chorus. In this paper, the trapping, acceleration and escape of electrons in Landau resonance with a whistler mode wave packet are discussed. It is shown that acceleration can occur by both inhomogeneous and dispersive effects. The maximum energy gained is controlled by the points where trapping and escape occur. Large energy changes are possible if the frequency of the wave packet or the magnetic field strength increase between the trapping and escape points. Various trapping and escape mechanisms are discussed.

  17. Exact elegant Laguerre-Gaussian vector wave packets.

    Science.gov (United States)

    Nasalski, W

    2013-03-15

    An exact closed-form representation is derived of a vector elegant Laguerre-Gaussian wave packet. Its space-time representation consists of three mutually orthogonal field components--of a common azimuthal index and different radial indices--uniquely distinguished by first three powers of the paraxial parameter. The transverse components are of tm-radial and te-azimuthal polarization and appear, under their normal incidence, to be eigenmodes of any horizontally planar, homogeneous and isotropic structure, with eigenvalues given by the reflection and transmission coefficients. In this context, the interrelations between the cross-polarization symmetries of wave packets in free space and at medium planar interfaces are discussed.

  18. 106-17 Telemetry Standards Chapter 7 Packet Telemetry Downlink

    Science.gov (United States)

    2017-07-31

    Figure 7-22. PTFR Payload Structure .................................................................................... 7-13 Figure 7-23. Start of...Acronyms IP Internet Protocol IPv4 Internet Protocol, Version 4 IPv6 Internet Protocol, Version 6 LLP low-latency PTDP MAC media access control...o 4’b0101: PT Internet Protocol (IP) Packet o 4’b0110: PT Chapter 24 TmNSMessage Packet o 4’b0111 – 4’b1111: Reserved • Fragment (bits 17 – 16

  19. Wave packet dynamics of photon-added coherent states

    Science.gov (United States)

    Sudheesh, C.; Lakshmibala, S.; Balakrishnan, V.

    2005-09-01

    We show in the framework of a tractable model that revivals and fractional revivals of wave packets afford clear signatures of the extent of departure from coherence and from Poisson statistics of an initial state of the radiation field propagating in a nonlinear medium. We establish this by considering a generic Hamiltonian which models wave packet propagation in a Kerr-like medium, and comparing the non-classical effects displayed by an initial photon-added coherent state with that of an inital ideal coherent state.

  20. Control of Wave Packet Revivals Using Geometric Phases

    Science.gov (United States)

    Seshadri, S.; Lakshmibala, S.; Balakrishnan, V.

    2000-10-01

    Wave packets in a system governed by a Hamiltonian with a generic nonlinear spectrum typically exhibit both full and fractional revivals. It is shown that, by varying the parameters in the Hamiltonian cyclically with a period T and thus inducing suitable geometric phases in the states, fractional revivals can be eliminated at the relevant times T, 2 T,... . Further, with the introduction of this time step T, the occurrence of near full revivals can be mapped onto that of Poincaré recurrences in an irrational rotation map of the circle. The distinctive recurrence statistics of the latter can thus serve as a clear signature of the dynamics of wave packet revivals.

  1. Preferred access in packet-switching radio networks

    Science.gov (United States)

    Shacham, N.

    Channel-access protocols that provide prioritized access to a common channel in a packet switching network are considered. The elements of such protocols are discussed and a specific protocol that integrates two types of packets is proposed. A probabilistic model of the protocol is presented, and its analysis yields the throughput-delay characteristics of the two classes and the interaction between them. The model is analyzed by a method similar to the one used in priority queues; this method allows consideration of each class separately, thus reducing the computational effort substantially.

  2. Speech transport in packet-radio networks with mobile nodes

    Science.gov (United States)

    Shacham, N.; Craighill, E. J.; Poggio, A. A.

    1983-12-01

    A research effort to provide speech-carrying capabilities to a data-oriented packet-switching radio network is described. The features of the network that limit its ability to carry packetized speech are discussed, and their effects on the network performance are analyzed. A new protocol, called duct routing, that enhances the network capabilities in a mobile environment is presented. That protocol makes use of repeater redundancy to compensate for loss of communication connectivity due to node mobility. A series of experiments to evaluate the network performance in carrying speech traffic, both with data and voice protocols, is described, and the results are presented and discussed.

  3. A first packet processing subdomain cluster model based on SDN

    Science.gov (United States)

    Chen, Mingyong; Wu, Weimin

    2017-08-01

    For the current controller cluster packet processing performance bottlenecks and controller downtime problems. An SDN controller is proposed to allocate the priority of each device in the SDN (Software Defined Network) network, and the domain contains several network devices and Controller, the controller is responsible for managing the network equipment within the domain, the switch performs data delivery based on the load of the controller, processing network equipment data. The experimental results show that the model can effectively solve the risk of single point failure of the controller, and can solve the performance bottleneck of the first packet processing.

  4. Gabor Wave Packet Method to Solve Plasma Wave Equations

    Energy Technology Data Exchange (ETDEWEB)

    A. Pletzer; C.K. Phillips; D.N. Smithe

    2003-06-18

    A numerical method for solving plasma wave equations arising in the context of mode conversion between the fast magnetosonic and the slow (e.g ion Bernstein) wave is presented. The numerical algorithm relies on the expansion of the solution in Gaussian wave packets known as Gabor functions, which have good resolution properties in both real and Fourier space. The wave packets are ideally suited to capture both the large and small wavelength features that characterize mode conversion problems. The accuracy of the scheme is compared with a standard finite element approach.

  5. Analysis and implementation of packet preemption for Time Sensitive Networks

    DEFF Research Database (Denmark)

    Zhou, Zifan; Yan, Ying; Ruepp, Sarah Renée

    2017-01-01

    A standard priority-queuing system is capable of arranging packets with different traffic classes to guarantee a relatively low latency for the high priority traffic. However, in practical cases, severe delay may be caused by starting a large, low-priority frame ahead of a time-critical frame....... In this paper, interspersed express traffic is evaluated, which enables preemption of non-time-critical transmission, in particular, the preemptive queuing system allows the cut-through transmission for critical traffic and minimizes the jitter. We analyse the performance of packet preemption through a system...

  6. Modulation instability of wave packets propagating in inhomogeneous nonlinear fiber

    Science.gov (United States)

    Lapin, V. A.; Fotiadi, A. A.

    2017-05-01

    The formation conditions and the effective gain of frequency-modulated soliton wave packets in a non-uniform along the length of active optical fibers were investigated. For packets modulated wave propagating in the nonlinear dependence of the fibers with the dispersion of the fiber length, the power of the generated pulses can be considerably increased in comparison with the homogeneous fibers. Due to the constant growth of the spectral width of the generated pulse sequence can no longer return to the state of the modulated continuous wave. As a result, the pulse duration with some fluctuations steadily declining. The amplitude and period of these oscillations are also reduced.

  7. Symmetry and conservation laws in semiclassical wave packet dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Ohsawa, Tomoki, E-mail: tomoki@utdallas.edu [Department of Mathematical Sciences, The University of Texas at Dallas, 800 W Campbell Rd., Richardson, Texas 75080-3021 (United States)

    2015-03-15

    We formulate symmetries in semiclassical Gaussian wave packet dynamics and find the corresponding conserved quantities, particularly the semiclassical angular momentum, via Noether’s theorem. We consider two slightly different formulations of Gaussian wave packet dynamics; one is based on earlier works of Heller and Hagedorn and the other based on the symplectic-geometric approach by Lubich and others. In either case, we reveal the symplectic and Hamiltonian nature of the dynamics and formulate natural symmetry group actions in the setting to derive the corresponding conserved quantities (momentum maps). The semiclassical angular momentum inherits the essential properties of the classical angular momentum as well as naturally corresponds to the quantum picture.

  8. Integrated model for line balancing with workstation inventory management

    Directory of Open Access Journals (Sweden)

    Dilip Roy

    2010-06-01

    Full Text Available In this paper, we address the optimization of an integrated line balancing process with workstation inventory management. While doing so, we have studied the interconnection between line balancing and its conversion process. Almost each and every moderate to large manufacturing industry depends on a long and integrated supply chain, consisting of inbound logistic, conversion process and outbound logistic. In this sense an approach addresses a very general problem of integrated line balancing. Research works reported in the literature so far mainly deals with minimization of cost for inbound and outbound logistic subsystems. In most of the cases conversion process has been ignored. We suggest a generic approach for linking the balancing of the line of production in the conversion area with the customers’ rate of demand in the market and for configuring the related stock chambers. Thus, the main aim of this paper is to translate the underlying problem in the form of mixed nonlinear programming problem and design the optimum supply chain so that the total inventory cost and the cost of balancing loss of the conversion process is jointly minimized and ideal cycle time of the production process is determined along with ideal sizes of the stock chambers. A numerical example has been added to demonstrate the suitability of our approach.

  9. An Iterative Approach To Development Of A PACS Display Workstation

    Science.gov (United States)

    O'Malley, Kathleen G.

    1989-05-01

    An iterative prototyping approach has been used in the development of requirements for a new user interface for the display workstation in the CommView system product line. This approach involves many steps, including development of the preliminary concept, validation and ranking of ideas within that concept, prototyping, evaluating, and revising. We describe in this paper the process undertaken to design and evaluate the new user interface. Staff at Abbott Northwestern Hospital, Bowman Gray/Baptist Hospital Medical Center, Duke University Medical Center, Georgetown University Medical Center and Robert Wood Johnson University Hospital participated in various aspects of the study. The subject population included radiologists, residents, technologists and staff physicians from several areas in the hospitals. Subjects participated in in-depth interviews, answered questionnaires, and performed specific tasks, to aid our development process. We feel this method has resulted in a product that will achieve a high level of customer satisfaction, developed in less time than a traditional approach. Some of the reasons we believe in the value of this approach are: • Users may not be able to describe their needs in terms that designers are expecting, leading to misinterpretation; • Users may not be able to choose between options without seeing them; • Users needs and choices evolve with experience; • Users true choices and needs may not seem logical to one not performing those tasks (i.e., the designers).

  10. Design and analysis of wudu’ (ablution) workstation for elderly in Malaysia

    Science.gov (United States)

    Aman, A.; Dawal, S. Z. M.; Rahman, N. I. A.

    2017-06-01

    Wudu’ (Ablution) workstation is one of the facilities used by most Muslims in all categories. At present, there are numbers of design guidelines for praying facilities but still lacking on wudu’ (ablution) area specification especially or elderly. Thus, It is timely to develop an ergonomic wudu’ workstation for elderly to perform ablution independently and confidently. This study was conducted to design an ergonomic ablution unit for the Muslim’s elderly in Malaysia. An ablution workstation was designed based on elderly anthropometric dimensions and was then analyse using CATIA V5R21 for posture investigation using RULAs. The results of the study has identified significant anthropometric dimensions in designing wudu’ (ablution) workstation for elderly people. This study can be considered as preliminary study for the development of an ergonomic ablution design for elderly. This effort will become one of the significant social contributions to our elderly population in developing our nation holistically.

  11. Ergonomics standards and guidelines for computer workstation design and the impact on users' health - a review.

    Science.gov (United States)

    Woo, E H C; White, P; Lai, C W K

    2016-03-01

    This paper presents an overview of global ergonomics standards and guidelines for design of computer workstations, with particular focus on their inconsistency and associated health risk impact. Overall, considerable disagreements were found in the design specifications of computer workstations globally, particularly in relation to the results from previous ergonomics research and the outcomes from current ergonomics standards and guidelines. To cope with the rapid advancement in computer technology, this article provides justifications and suggestions for modifications in the current ergonomics standards and guidelines for the design of computer workstations. Practitioner Summary: A research gap exists in ergonomics standards and guidelines for computer workstations. We explore the validity and generalisability of ergonomics recommendations by comparing previous ergonomics research through to recommendations and outcomes from current ergonomics standards and guidelines.

  12. Robotic, MEMS-based Multi Utility Sample Preparation Instrument for ISS Biological Workstation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project will develop a multi-functional, automated sample preparation instrument for biological wet-lab workstations on the ISS. The instrument is based on a...

  13. Effects of two workstation positions for below-knee assembly work on upper extremity muscle activity.

    Science.gov (United States)

    Shin, Seung-Je; Yoo, Won-Gyu

    2015-01-01

    [Purpose] This study was performed to determine which set of below-knee working conditions minimizes upper extremity muscle activity and which of upward- or downward-direction workstations poses the greater risk of upper extremity disorder. [Subjects] The study population consisted of 15 young male workers. [Methods] EMG activities of the right anterior deltoid, biceps brachii, and lower trapezius muscles were measured in two below-knee assembly workstation positions. [Results] The anterior deltoid and biceps brachii muscle activities of Position 1 were significantly higher than those of Position 2. The lower trapezius muscle activity of Position 2 was significantly higher than that of Position 1. [Conclusion] Upward-direction workstations appear to pose a greater risk of upper extremity disorder than downward-direction workstations in below-knee assembly work.

  14. Simulation Technology Research Division assessment of the IBM RISC SYSTEM/6000 Model 530 workstation

    Energy Technology Data Exchange (ETDEWEB)

    Valdez, G.D. (Applied Methods, Inc., Albuquerque, NM (USA)); Halbleib, J.A.; Kensek, R.P.; Lorence, L.J. (Sandia National Labs., Albuquerque, NM (USA))

    1990-11-01

    A workstation manufactured by International Business Machines Corporation (IBM) was loaned to the Simulation Technology Research Division for evaluation. We have found that these new UNIX workstations from IBM have superior cost to performance ratios compared to the CRAY supercomputers and Digital's VAX machines. Our appraisal of this workstation included floating-point performance, system and environment functionality, and cost effectiveness. Our assessment was based on a suite of radiation transport codes developed at Sandia that constitute the bulk of our division's computing workload. In this report, we also discuss our experience with features that are unique to this machine such as the AIX operating system and the XLF Fortran Compiler. The interoperability of the RS/6000 workstation with Sandia's network of CRAYs and VAXs was also assessed.

  15. Novel method for quantitative assessment of physical workload of healthcare workers by a tetherless ergonomics workstation.

    Science.gov (United States)

    Smith, Warren D; Alharbi, Kamal A; Dixon, Jeremy B; Reggad, Hind

    2012-01-01

    Healthcare workers are at risk of physical injury. Our laboratory has developed a tetherless ergonomics workstation that is suitable for studying physicians' and nurses' physical workloads in clinical settings. The workstation uses wearable sensors to record multiple channels of body orientation and muscle activity and wirelessly transmits them to a base station laptop computer for display, storage, and analysis. The ergonomics workstation generates long records of multi-channel data, so it is desired that the workstation automatically process these records and provide graphical and quantitative summaries of the physical workloads experienced by the healthcare workers. This paper describes a novel method of automated quantitative assessment of physical workload, termed joint cumulative amplitude-duration (JCAD) analysis, that has advantages over previous methods and illustrates its use in a comparison of the physical workloads of robotically-assisted surgery versus manual video-endoscopic surgery.

  16. Synchronization, retiming and OTDM of an asynchronous 10 Gigabit Ethernet NRZ packet using a time lens for Terabit Ethernet

    DEFF Research Database (Denmark)

    Hu, Hao; Laguardia Areal, Janaina; Mulvad, Hans Christian Hansen

    2011-01-01

    An asynchronous 10G Ethernet packet is synchronized and retimed to a master clock using a time lens. The NRZ packet is converted into an RZ packet and multiplexed with a serial 1.28 Tb/s signal.......An asynchronous 10G Ethernet packet is synchronized and retimed to a master clock using a time lens. The NRZ packet is converted into an RZ packet and multiplexed with a serial 1.28 Tb/s signal....

  17. Functionalizing 2PP-fabricated microtools for optical manipulation on the BioPhotonics Workstation

    DEFF Research Database (Denmark)

    Matsuoka, Tomoyo; Nishi, Masayuki; Sakakura, Masaaki

    Functionalization of the structures fabricated by two-photon polymerization was achieved by coating them with sol-gel materials, which contain calcium indicators. The structures are expected to work potentially as nano-sensors on the BioPhotonics Workstation.......Functionalization of the structures fabricated by two-photon polymerization was achieved by coating them with sol-gel materials, which contain calcium indicators. The structures are expected to work potentially as nano-sensors on the BioPhotonics Workstation....

  18. Massachusetts Bay - Internal Wave Packets Digitized from SAR Imagery and Intersected with Bathymetry

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This feature class contains internal wave packets digitized from SAR imagery and intersected with bathymetry for Massachusetts Bay. The internal wave packets were...

  19. Direct-Sequence Spread-Spectrum Modulation for Utility Packet Transmission in Underwater Acoustic Communication Networks

    National Research Council Canada - National Science Library

    Duke, Peter

    2002-01-01

    ...) modulation for utility-packet transmission in Seaweb underwater wireless acoustic communications networks, Seaweb networks require robust channel-tolerant utility packets having a low probability of detection (LPD...

  20. An approximate analysis of delay for fixed and variable length packets in an unslotted ALOHA channel

    Science.gov (United States)

    Ferguson, M. J.

    1977-01-01

    In this paper we compute the mean delay for an unslotted ALOHA random access channel for both fixed and variable length packets. The analysis is based on the concept of a user cycle and obtains steady state results. When the channel is 'stable', the results seem quite accurate. The input parameters to the model are the number of users, the mean think time, and mean retransmission time. The model yields total traffic, throughput and delay but only the latter is emphasized here. Because of the steady state nature of the analysis, no information is obtained on stability. The results are verified by simulation.

  1. Stacked optical code label for multicasting in optical packet switching networks.

    Science.gov (United States)

    Xin, Ming; Chen, Minghua; Chen, Hongwei; Xie, Shizhong

    2009-03-16

    Stacked optical code (OC) label and its en/decoder based on fiber Bragg gratings (FBG) are proposed and experimentally demonstrated. This kind of label can carry several nodes' address information simultaneously in optical packet switching networks, so it can be employed in optical multicasting and simplify the node's structure a lot. The en/decoder is fabricated with high precision by our FBG techniques, and the experiment results show that the stacked OC label can support optical multicasting very well. (c) 2009 Optical Society of America

  2. PARALLEL QUICK SEARCH ALGORITHM TO SPEED PACKET PAYLOAD FILTERING IN NIDS

    OpenAIRE

    Hnaif, Adnan A.; MOHAMMAD ALHALAIQAH; OMAR ABOUABDALLA; SURESWARAN RAMADASS; Kadhum, Mohammed M.

    2009-01-01

    An Intrusion Detection System (IDS) is a system to detect intruders who try to hack in to the network and steal information and report them to the network administrator. There are many tools used in this field, snort consider one of the most tools mostly used in Network Intrusion Detection System (NIDS). In spite of consuming 31% of total processing due to string matching, and 80% of total processing in case of web-intensive traffic, snort using its rule sets to determine which packets are al...

  3. Effect of Standing or Walking at a Workstation on Cognitive Function: A Randomized Counterbalanced Trial.

    Science.gov (United States)

    Bantoft, Christina; Summers, Mathew J; Tranent, Peter J; Palmer, Matthew A; Cooley, P Dean; Pedersen, Scott J

    2016-02-01

    In the present study, we examined the effect of working while seated, while standing, or while walking on measures of short-term memory, working memory, selective and sustained attention, and information-processing speed. The advent of computer-based technology has revolutionized the adult workplace, such that average adult full-time employees spend the majority of their working day seated. Prolonged sitting is associated with increasing obesity and chronic health conditions in children and adults. One possible intervention to reduce the negative health impacts of the modern office environment involves modifying the workplace to increase incidental activity and exercise during the workday. Although modifications, such as sit-stand desks, have been shown to improve physiological function, there is mixed information regarding the impact of such office modification on individual cognitive performance and thereby the efficiency of the work environment. In a fully counterbalanced randomized control trial, we assessed the cognitive performance of 45 undergraduate students for up to a 1-hr period in each condition. The results indicate that there is no significant change in the measures used to assess cognitive performance associated with working while seated, while standing, or while walking at low intensity. These results indicate that cognitive performance is not degraded with short-term use of alternate workstations. © 2015, Human Factors and Ergonomics Society.

  4. Walking Workstation Use Reduces Ambulatory Blood Pressure in Adults With Prehypertension.

    Science.gov (United States)

    Zeigler, Zachary S; Swan, Pamela D; Bhammar, Dharini M; Gaesser, Glenn A

    2015-06-16

    The acute effect of low-intensity walking on blood pressure (BP) is unclear. To determine if the acute use of a walking workstation reduces ambulatory blood pressure (ABP) in prehypertensive men and women. Ten prehypertensive adults participated in a randomized, cross-over study that included a control workday and a walking workstation workday. ABP was measured for 7 hour during the workday and for 6 hour after work. Both systolic BP (SBP) (134 ± 14 vs. 137 ± 16 mmHg; P = .027) and diastolic BP (DBP) (79 ± 10 vs. 82 ± 12 mmHg; P = .001) were lower on the walking workstation day. Postwork hours (4:00 PM-10:00 PM), SBP (129 ± 13 vs. 133 ± 14 mmHg; P = .008), and DBP (74 ± 11 vs. 78 ± 13 mmHg; P = .001) were also lower on the walking workstation day. DBP load was significantly lower during the walking workstation day, with only 14% of the readings above 90 mmHg compared with 22% of the control day readings (P = .037). Accumulation of very-light-intensity physical activity (~2 METs) over the course of a single work day using a walking workstation may reduce BP burden in prehypertensive individuals.

  5. [A particular anthropometric method for the study of accessibility of a workstation].

    Science.gov (United States)

    Molinaro, V; Del Ferraro, S

    2008-01-01

    One of the main factors which can involve musculo-skeletal disorders is the assumption of awkward postures. These lasts can be caused, in some cases, by a no-suitable collocation of some devices which are indispensable for the work. It is possible to evaluate if the chosen collocation is adequate or not by studying the accessibility of the workstation with a special regard for the accessibility of the devices placed inside the workstation. EN ISO 14738:2002 is a specific standard which has been adopted in Italy as UNI EN ISO 14738:2004. This standard gives some useful requirements, in terms of accessibility, to design a workstation at no-mobile machinery. In this study, the authors have analyzed a check out workstation by following the requirements described in UNI EN ISO 14738:2004. Critical aspects, related to the organization both of the work activities either of the workstation, have been highlighted taking into account standard criteria. Finally the authors make a new design of the check out workstation trying to optimize device collocation in order to reduce awkward postures. The new configuration has been investigated by applying the criteria mentioned in the standard.

  6. An Experimental Exploration of the Impact of Sensor-Level Packet Loss on Network Intrusion Detection

    Science.gov (United States)

    2015-07-01

    gator010 abridged with the packet dropper using the capped-by-packets algorithm and abridged by pcapreplay ............ 16 Fig. 10 Sigmoid nonlinear...is not random but is very similiar to both the results of the capped-by-packet algorithm of the packet dropper and a sigmoid function. When we used...the PLR verses the ALR will allow us to compare the results against our results from the theoretical exploration.2 We should be able to use curve

  7. Excitation of localized wave packet in swept-wing supersonic boundary layer

    Directory of Open Access Journals (Sweden)

    Yatskikh Aleksey

    2017-01-01

    Full Text Available The evolution of the artificial wave packet in swept-wing supersonic boundary layer was experimentally studied at M = 2. The localized disturbances were generated by a pulse glow discharge. Measurements were provided by a hot-wire anemometer. The spatial structure of the wave packet was studied. It was found that the wave packet has an asymmetric shape. In addition, the velocity of the propagation downstream of the wave packet was estimated.

  8. 160 Gbit/s optical packet switching using a silicon chip

    DEFF Research Database (Denmark)

    Hu, Hao; Ji, Hua; Galili, Michael

    2012-01-01

    We have successfully demonstrated 160 Gbit/s all-optical packet switching based on cross-phase modulation using a silicon chip. Error free performance is achieved for the 4-to-1 switched 160 Gbit/s packet.......We have successfully demonstrated 160 Gbit/s all-optical packet switching based on cross-phase modulation using a silicon chip. Error free performance is achieved for the 4-to-1 switched 160 Gbit/s packet....

  9. Optical frame synchronizer for 10 G Ethernet packets aiming at 1 Tb/s OTDM Ethernet

    DEFF Research Database (Denmark)

    Hu, Hao; Palushani, Evarist; Laguardia Areal, Janaina

    2010-01-01

    Synchronization of 10 G Ethernet packets to a local clock was demonstrated using a phase modulator and a SMF as retiming elements. Error free performances for the synchronized packets with different lengths were achieved.......Synchronization of 10 G Ethernet packets to a local clock was demonstrated using a phase modulator and a SMF as retiming elements. Error free performances for the synchronized packets with different lengths were achieved....

  10. Non-linear wave packet dynamics of coherent states

    Indian Academy of Sciences (India)

    We have compared the non-linear wave packet dynamics of coherent states of various symmetry groups and found that certain generic features of non-linear evolution are present in each case. Thus the initial coherent structures are quickly destroyed but are followed by Schrödinger cat formation and revival. We also report ...

  11. Hardware packet pacing using a DMA in a parallel computer

    Science.gov (United States)

    Chen, Dong; Heidelberger, Phillip; Vranas, Pavlos

    2013-08-13

    Method and system for hardware packet pacing using a direct memory access controller in a parallel computer which, in one aspect, keeps track of a total number of bytes put on the network as a result of a remote get operation, using a hardware token counter.

  12. Wave packet construction in three-dimensional quantum billiards ...

    Indian Academy of Sciences (India)

    as the symmetry breaks due to commensurate or incommensurate ratio of sides. Keywords. Three-dimensional bound systems; revivals and collapses; quantum mechanics. PACS Nos 03.65.Ge; 03.65.Yz; 42.50.Md. 1. Introduction. The study of time evolution of the unbound and bound-state wave packet illuminates.

  13. Application of Cellular Automata to Detection of Malicious Network Packets

    Science.gov (United States)

    Brown, Robert L.

    2014-01-01

    A problem in computer security is identification of attack signatures in network packets. An attack signature is a pattern of bits that characterizes a particular attack. Because there are many kinds of attacks, there are potentially many attack signatures. Furthermore, attackers may seek to avoid detection by altering the attack mechanism so that…

  14. The Effect of Double Buffer Management in Packet Analysis of ...

    African Journals Online (AJOL)

    of file downloads between the HTTP server and clients are also varied to follow the behavior of data. The buf(er ... to accommodate. Keywords: buffer, traffic analysis, packet, HTTP, server, clients, byte, double buffer. ... Mobile Ad hoc Networks (MANETs), each node serves as a host as well as a router and uses consequently ...

  15. A CURRICULUM FOR ENGLISH, STUDENT PACKET, GRADE 12.

    Science.gov (United States)

    Nebraska Univ., Lincoln. Curriculum Development Center.

    THE LITERATURE PROGRAM OF THE GRADE 12 STUDENT PACKET OF THE NEBRASKA ENGLISH CURRICULUM CONSISTS OF A SELECTIVE SURVEY OF ENGLISH LITERATURE FROM THE RENAISSANCE TO THE 20TH CENTURY. IT BEGINS WITH A UNIT ON SHAKESPEAREAN TRAGEDY IN WHICH STUDENTS READ REVENGE TRAGEDIES--SENECA'S "THYESTES" AND KYD'S "THE SPANISH TRAGEDY"--AS…

  16. The Sphinx and the Pyramids at Giza. Educational Packet.

    Science.gov (United States)

    Gagliano, Sara; Rapport, Wendy

    This packet of materials was created to accompany the exhibit "The Sphinx and the Pyramids: 100 Years of American Archaeology at Giza" at the Semitic Museum of Harvard University. The lessons and teacher's guide focus on the following: (1) "The Mystery of the Secret Tomb" where students take on the role of an archaeologist by…

  17. Analysis Of Packets Delay In Wireless Data Networks

    Directory of Open Access Journals (Sweden)

    Krivchenkov Aleksandr

    2015-12-01

    Full Text Available The networks with wireless links for automation control applications traffic transmission when packets have small size and application payload is predictable are under consideration. Analytical model for packets delay on their propagation path through the network is proposed. Estimations for network architectures based on WiFi and Bluetooth wireless technologies are made. The specifications for physical layer 802.11 a/b/g/n and 802.15.1 are under consideration. Analytical and experimental results for delivered network bandwidth for different network architecture, traffic structure and wireless technologies were compared to validate that basic mechanisms are correctly taken into account in the model. It is shown that basic effects are taken into account and further accuracy “improvement” of the model will give not more than 5%. As a result that is important for automation control applications we have reliably received the lowest possible level for packets delay in one wireless link. For 802.11 it is of order of 0.2 ms, for 802.15.1 it is 1.25 ms and is true when application packet can be transferred by one data frame.

  18. A simple livelock-free algorithm for packet switching

    National Research Council Canada - National Science Library

    Shyamasundar, R.K

    1984-01-01

    ... as a livelock-free algorithm for packet switching is obtained using the strategy of the banker's algorithm. Furthermore, the solution obtained is interpreted for the hyper-fast banker's problem. 1. Introduction In most cases, the occurrence of network deadlock has a horrendous impact upon network users. When the deadlocks are discovered, they are frequ...

  19. "Macbeth." A Play Packet To Accompany "Elementary, My Dear Shakespeare."

    Science.gov (United States)

    Engen, Barbara; Campbell, Joy

    Intended for use by elementary school teachers as a supplement to the book, "Elementary, My Dear Shakespeare," or for use by itself to produce one Shakespeare play, this play packet contains ready-to-reproduce materials for the production of "Macbeth." Materials include: staging suggestions for scenery, props, lighting, and…

  20. INTERNET TRAFFIC AND PACKET ROUND TRIP DELAY SELF ...

    African Journals Online (AJOL)

    Long Range Dependence(LRD). In this work, it has been shown that the Internet traffic and Packet. Round Trip Delay visuaiized as a time series are statistically selfsimilar. The autocorrelation function decays reveals the data ..... satisfied by the well-known family of "Pareto. Distribution", originally introduced for modelling.

  1. Solar Energy Education Packet for Elementary & Secondary Students. Revised Edition.

    Science.gov (United States)

    Center for Renewable Resources, Washington, DC.

    The arrangement of this packet is essentially evolutionary, with a conscious effort to alternate reading assignments, activities and experiments. It begins with solar energy facts and terminology as background to introduce the reader to basic concepts. It progresses into a discussion of passive solar systems. This is followed by several projects…

  2. Solar Energy Education Packet for Elementary & Secondary Students.

    Science.gov (United States)

    Center for Renewable Resources, Washington, DC.

    The arrangement of this packet is essentially evolutionary, with a conscious effort to alternate reading assignments, activities and experiments. It begins with solar energy facts and terminology as background to introduce the reader to basic concepts. It progresses into a discussion of passive solar systems. This is followed by several projects…

  3. Designs and algorithms for packet and content inspection

    NARCIS (Netherlands)

    Sourdis, I.

    2007-01-01

    This dissertation deals with essential issues pertaining to high performance processing for network security and deep packet inspection. The proposed solutions keep pace with the increasing number and complexity of known attack descriptions providing multi-Gbps processing rates. We advocate the use

  4. Energy Crisis: Libya's and Nigeria's Role. Resource Packet.

    Science.gov (United States)

    African-American Inst., New York, NY. School Services Div.

    This resource packet contains practical suggestions and resource materials to help secondary teachers teach about Libya's and Nigeria's roles in the energy crisis. Students become acquainted with the governments and cultures of the two countries, examine their social problems, and learn how the Libyan and Nigerian governments are using money from…

  5. Green partial packet recovery in wireless sensor networks

    KAUST Repository

    Daghistani, Anas

    2015-08-18

    Partial packet recovery is well known for increasing network throughput and reducing frame retransmissions. However, partial packet recovery methods in the literature are not energy-aware and hence they are not suitable for the battery powered wireless sensor motes. We propose Green-Frag, a novel adaptive partial packet recovery mechanism that is energy friendly. It can help prolonging the battery life of wireless sensor motes that are usually resource constrained. It dynamically partitions the frame into smaller blocks to avoid dropping the whole frame due to a single bit error. Also, Green-Frag is able to tolerate high interference and save energy by varying the transmit power based on channel quality and interference pattern. We experimentally evaluate the energy efficiency as well as goodput and delay of Green-Frag using our TelosB sensor mote testbed. We find that Green-Frag reduces energy consumption by 33% on average compared to the state of the art partial packet recovery scheme in the literature in the presence of Wi-Fi interference. In the worst case, this reduction in energy consumption comes at the cost of 10% reduction in goodput. Finally, Green-Frag reduces the latency by 22% on average compared to other static frame fragmentation schemes.

  6. Time-lens based optical packet pulse compression and retiming

    DEFF Research Database (Denmark)

    Laguardia Areal, Janaina; Hu, Hao; Palushani, Evarist

    2010-01-01

    This paper presents a new optical circuit that performs both pulse compression and frame synchronization and retiming. Our design aims at directly multiplexing several 10G Ethernet data packets (frames) to a high-speed OTDM link. This scheme is optically transparent and does not require clock...

  7. Jittering wave-packet models for subsonic jet noise

    Science.gov (United States)

    Cavalieri, André V. G.; Jordan, Peter; Agarwal, Anurag; Gervais, Yves

    2011-08-01

    Three simplified wave-packet models of the coherent structures in subsonic jets are presented. The models comprise convected wave-packets with time-dependent amplitudes and spatial extents. The dependence of the radiated sound on the temporal variations of the amplitude and spatial extent of the modulations are studied separately in the first two model problems, being considered together in the third. Analytical expressions for the radiated sound pressure are obtained for the first and third models. Results show that temporally localised changes in the wave-packet can lead to radiation patterns which are directional and which comprise high-amplitude bursts; such intermittency is observed in subsonic jets at the end of the potential core, and so the models may help explain the higher noise levels and intermittent character of the sound radiated to low emission angles for subsonic jets. By means of an efficiency metric, relating the radiated acoustic power to the fluctuation energy of the source, we show that the source becomes more powerful as its temporal localisation is increased. This result extends that of Sandham et al. (Journal of Sound and Vibration 294(1) (2006) 355-361) who found similar behaviour for an infinitely extended wavy-wall. The pertinence of the model is assessed using two sets of data for a Mach 0.9 jet. One corresponds to a direct numerical simulation (DNS) of a Reynolds number 3600 turbulent jet and the other to a large eddy simulation (LES) of a Reynolds number 4×10 5 jet. Both time-averaged and time-dependent amplitudes and spatial extents are extracted from the velocity field of the numerical data. Computing the sound field generated by the wave-packet models we find for both simulations that while the wave-packet with a time-averaged envelope shows discrepancies of more than an order of magnitude with the sound field, when the wave-packet 'jitters' in a way similar to the intermittency displayed by the simulations, we obtain agreement to

  8. Time-resolved Imaging of H2 + (D2 +) Nuclear Wave Packets

    Science.gov (United States)

    Ergler, Th.; Rudenko, A.; Feuerstein, B.; Zrost, K.; Schröter, C. D.; Moshammer, R.; Ullrich, J.

    The spatio-temporal evolution of H2 + (D2 +) nuclear wave packets is mapped using time-resolved Coulomb explosion imaging. We visualize the motion of both dissociating and bound parts of the wave packet, observe its dephasing and subsequent revivals. The reconstructed probability density of the wave packet is in good agreement with earlier theoretical predictions.

  9. Random access with adaptive packet aggregation in LTE/LTE-A.

    Science.gov (United States)

    Zhou, Kaijie; Nikaein, Navid

    While random access presents a promising solution for efficient uplink channel access, the preamble collision rate can significantly increase when massive number of devices simultaneously access the channel. To address this issue and improve the reliability of the random access, an adaptive packet aggregation method is proposed. With the proposed method, a device does not trigger a random access for every single packet. Instead, it starts a random access when the number of aggregated packets reaches a given threshold. This method reduces the packet collision rate at the expense of an extra latency, which is used to accumulate multiple packets into a single transmission unit. Therefore, the tradeoff between packet loss rate and channel access latency has to be carefully selected. We use semi-Markov model to derive the packet loss rate and channel access latency as functions of packet aggregation number. Hence, the optimal amount of aggregated packets can be found, which keeps the loss rate below the desired value while minimizing the access latency. We also apply for the idea of packet aggregation for power saving, where a device aggregates as many packets as possible until the latency constraint is reached. Simulations are carried out to evaluate our methods. We find that the packet loss rate and/or power consumption are significantly reduced with the proposed method.

  10. Development of a mobile HIS/PACS workstation to assist critical cardiac patients in an intensive care unit

    Science.gov (United States)

    Gutierrez, Marco A.; Cestari, Idagene A.; Hamamoto, Gina; Bacht, Simão; Rebelo, Marina S.; Silva, João E. M. M.; Lage, Silvia G.

    2008-03-01

    The current study describes the experience in the implementation of a mobile HIS/PACS workstation to assist critical cardiac patients in an Intensive Care Unit (ICU). Recently, mobile devices connected to a WiFi network were incorporated to the Hospital information System, providing the same functionalities of common desktop counterpart. However, the use of commercially devices like PDAs and Pocket PCs presented a series of problems that are more emphasized in the ICUs 1) low autonomy of the batteries, which need constant recharges; 2) low robustness of the devices; 3) insufficient display area to show medical images and vital signals; 4) data entry remains a major problem and imposes an extra time consumption to the staff; 5) high cost when fully equipped with WiFi connection, optical reader to access bar codes and memory. To address theses problems we developed a mobile workstation (MedKart) that provides access the HIS and PACS systems, with all resources and an ergonomic and practical design to be used by physicians and nurses inside the ICU. The system fulfills the requirements to assist, in the point-of-care, critical cardiac patients in Intensive Care Units.

  11. High-Bandwidth Tactical-Network Data Analysis in a High-Performance-Computing (HPC) Environment: Packet-Level Analysis

    Science.gov (United States)

    2015-09-01

    The module takes 2 different types of input data cuts. The cuts come from Binary Large Object ( BLOb ) files and/or Packet Capture (PCAP) files. During...into CommsIp’s Process method. Though BLOb Nettap cuts5 and PCAP cuts are roughly the same, BLOb cuts contain more cut metadata. The metadata for... BLOb Nettap cut metadata also contains information about whether or not the data collection device experienced an overflow error (resulting in

  12. State-of-the-art digital photogrammetric workstations for topographic applications

    Science.gov (United States)

    Heipke, Christian

    1993-09-01

    Digital Photogrammetric Workstations (DPWS) have become a major focus of research within the photogrammetric community in the last year. This paper presents the state-of-the-art of DPWS. A DPWS is the main component of a Digital Photogrammetric Systems (DPS). A DPS is defined as hardware and software for deriving input data for Geographic Information Systems (GIS) as well as for Computer Aided Design (CAD) systems and other photogrammetric products from digital imagery using manual and automatic techniques. Besides the DPWS itself a DPS also includes A/D and D/A convertors for the imagery (digital cameras, film scanners, output devices for producing film and paper hardcopies). First design issues of a DPWS are addressed. Then, the question of automation versus interaction is discussed, and it is pointed out, where automation is possible in the chain of processing digital imagery. Subsequently a classification of the different kinds of DPWS according to their products is given. Then first experiences and results obtained by civilian mapping organizations involved in digital photogrammetry and using DPWS are described. Finally requirements for a broader use in practice and trends for further development in digital photogrammetry and in DPS are pointed out.

  13. The use of bicycle workstations to increase physical activity in secondary classrooms

    Directory of Open Access Journals (Sweden)

    Alicia Fedewa

    2017-11-01

    Full Text Available Background To date, the majority of interventions have implemented classroom-based physical activity (PA at the elementary level; however, there is both the potential and need to explore student outcomes at high-school level as well, given that very few studies have incorporated classroom-based PA interventions for adolescents. One exception has been the use of bicycle workstations within secondary classrooms. Using bicycle workstations in lieu of traditional chairs in a high school setting shows promise for enhancing adolescents’ physical activity during the school day. Participants and procedure The present study explored the effects of integrating bicycle workstations into a secondary classroom setting for four months in a sample of 115 adolescents using an A-B-A-B withdrawal design. The study took place in one Advanced Placement English classroom across five groups of students. Physical activity outcomes included average heart rate, and caloric expenditure. Behavioural outcomes included percentage of on-task/off-task behaviour and number of teacher prompts in redirecting off-task behaviour. Feasibility and acceptability data of using the bicycle workstations were also collected. Results Findings showed significant improvements in physical activity as measured by heart rate and caloric expenditure, although heart rate percentage remained in the low intensity range when students were on the bicycle workstations. No effects were found on students’ on-task behaviour when using the bicycle workstations. Overall, students found the bikes acceptable to use but noted disadvantages of them as well. Conclusions Using bicycle workstations in high-school settings appears promising for enhancing low-intensity physical activity among adolescents. The limitations of the present study and implications for physical activity interventions in secondary schools are discussed.

  14. Shoulder girdle muscle activity and fatigue in traditional and improved design carpet weaving workstations.

    Science.gov (United States)

    Allahyari, Teimour; Mortazavi, Narges; Khalkhali, Hamid Reza; Sanjari, Mohammad Ali

    2016-01-01

    Work-related musculoskeletal disorders in the neck and shoulder regions are common among carpet weavers. Working for prolonged hours in a static and awkward posture could result in an increased muscle activity and may lead to musculoskeletal disorders. Ergonomic workstation improvements can reduce muscle fatigue and the risk of musculoskeletal disorders. The aim of this study is to assess and to compare upper trapezius and middle deltoid muscle activity in 2 traditional and improved design carpet weaving workstations. These 2 workstations were simulated in a laboratory and 12 women carpet weavers worked for 3 h. Electromyography (EMG) signals were recorded during work in bilateral upper trapezius and bilateral middle deltoid. The root mean square (RMS) and median frequency (MF) values were calculated and used to assess muscle load and fatigue. Repeated measure ANOVA was performed to assess the effect of independent variables on muscular activity and fatigue. The participants were asked to report shoulder region fatigue on the Borg's Category-Ratio scale (Borg CR-10). Root mean square values in workstation A are significantly higher than in workstation B. Furthermore, EMG amplitude was higher in bilateral trapezius than in bilateral deltoid. However, muscle fatigue was not observed in any of the workstations. The results of the study revealed that muscle load in a traditional workstation was high, but fatigue was not observed. Further studies investigating other muscles involved in carpet weaving tasks are recommended. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  15. Field trial of 160 Gbit/s DWDM-based optical packet switching and transmission.

    Science.gov (United States)

    Furukawa, Hideaki; Wada, Naoya; Awaji, Yoshinari; Miyazaki, Tetsuya; Kong, Eddie; Chan, Peter; Man, Ray; Cincotti, Gabriella; Kitayama, Ken-ichi

    2008-07-21

    We demonstrated, for the first time, a field trial of 160 (16 lambda x 10) Gbit/s, fine granularity, DWDM-based optical packet switching and transmission by newly-developed burst-mode EDFAs and an optical packet switch prototype with multiple all-optical label processors. We achieved 64 km field transmission and switching of 160 (16 lambda x 10) Gbit/s DWDM-based optical packets encapsulating almost 10 Gbit/s IP packets with error-free operation (IP-packet-loss-rate <10(-6) and bit-error-rate <10(-9)).

  16. Towards Effective Trust-Based Packet Filtering in Collaborative Network Environments

    DEFF Research Database (Denmark)

    Meng, Weizhi; Li, Wenjuan; Kwok, Lam-For

    2017-01-01

    Overhead network packets are a big challenge for intrusion detection systems (IDSs), which may increase system burden, degrade system performance, and even cause the whole system collapse, when the number of incoming packets exceeds the maximum handling capability. To address this issue, packet...... filtration is considered as a promising solution, and our previous research efforts have proven that designing a trust-based packet filter was able to refine unwanted network packets and reduce the workload of a local IDS. With the development of Internet cooperation, collaborative intrusion detection...

  17. Array CGH data modeling and smoothing in Stationary Wavelet Packet Transform domain

    Directory of Open Access Journals (Sweden)

    Oraintara Soontorn

    2008-09-01

    Full Text Available Abstract Background Array-based comparative genomic hybridization (array CGH is a highly efficient technique, allowing the simultaneous measurement of genomic DNA copy number at hundreds or thousands of loci and the reliable detection of local one-copy-level variations. Characterization of these DNA copy number changes is important for both the basic understanding of cancer and its diagnosis. In order to develop effective methods to identify aberration regions from array CGH data, many recent research work focus on both smoothing-based and segmentation-based data processing. In this paper, we propose stationary packet wavelet transform based approach to smooth array CGH data. Our purpose is to remove CGH noise in whole frequency while keeping true signal by using bivariate model. Results In both synthetic and real CGH data, Stationary Wavelet Packet Transform (SWPT is the best wavelet transform to analyze CGH signal in whole frequency. We also introduce a new bivariate shrinkage model which shows the relationship of CGH noisy coefficients of two scales in SWPT. Before smoothing, the symmetric extension is considered as a preprocessing step to save information at the border. Conclusion We have designed the SWTP and the SWPT-Bi which are using the stationary wavelet packet transform with the hard thresholding and the new bivariate shrinkage estimator respectively to smooth the array CGH data. We demonstrate the effectiveness of our approach through theoretical and experimental exploration of a set of array CGH data, including both synthetic data and real data. The comparison results show that our method outperforms the previous approaches.

  18. Virtual slide telepathology workstation of the future: lessons learned from teleradiology☆

    Science.gov (United States)

    Krupinski, Elizabeth A.

    2013-01-01

    Summary The clinical reading environment for the 21st century pathologist looks very different than it did even a few short years ago. Glass slides are quickly being replaced by digital “virtual slides,” and the traditional light microscope is being replaced by the computer display. There are numerous questions that arise however when deciding exactly what this new digital display viewing environment will be like. Choosing a workstation for daily use in the interpretation of digital pathology images can be a very daunting task. Radiology went digital nearly 20 years ago and faced many of the same challenges so there are lessons to be learned from these experiences. One major lesson is that there is no “one size fits all” workstation so users must consider a variety of factors when choosing a workstation. In this article, we summarize some of the potentially critical elements in a pathology workstation and the characteristics one should be aware of and look for in the selection of one. Issues pertaining to both hardware and software aspects of medical workstations will be reviewed particularly as they may impact the interpretation process. PMID:19552939

  19. Virtual slide telepathology workstation-of-the-future: lessons learned from teleradiology.

    Science.gov (United States)

    Krupinski, Elizabeth A

    2009-11-01

    The clinical reading environment for the twenty-first century pathologist looks very different than it did even a few short years ago. Glass slides are quickly being replaced by digital "virtual slides" and the traditional light microscope is being replaced by the computer display. There are numerous questions that arise however when deciding exactly what this new digital display viewing environment be like. Choosing a workstation for daily use in the interpretation of digital pathology images can be a very daunting task. Radiology went digital nearly 20 years ago and faced many of the same challenges so there are lessons to be learned from these experiences. One major lesson is that there is no "one size fits all" workstation so users must consider a variety of factors when choosing a workstation. In this article, we summarize some of the potentially critical elements in a pathology workstation and the characteristics one should be aware of and look for in the selection of one. Issues pertaining to both hardware and software aspects of medical workstations will be reviewed particularly as they may impact the interpretation process.

  20. Virtual slide telepathology workstation of the future: lessons learned from teleradiology.

    Science.gov (United States)

    Krupinski, Elizabeth A

    2009-08-01

    The clinical reading environment for the 21st century pathologist looks very different than it did even a few short years ago. Glass slides are quickly being replaced by digital "virtual slides," and the traditional light microscope is being replaced by the computer display. There are numerous questions that arise however when deciding exactly what this new digital display viewing environment will be like. Choosing a workstation for daily use in the interpretation of digital pathology images can be a very daunting task. Radiology went digital nearly 20 years ago and faced many of the same challenges so there are lessons to be learned from these experiences. One major lesson is that there is no "one size fits all" workstation so users must consider a variety of factors when choosing a workstation. In this article, we summarize some of the potentially critical elements in a pathology workstation and the characteristics one should be aware of and look for in the selection of one. Issues pertaining to both hardware and software aspects of medical workstations will be reviewed particularly as they may impact the interpretation process.

  1. Experimental and trial-based study of Resilient Packet Ring

    Science.gov (United States)

    Ramnath, Vasudha; Cheng, Heng Seng; Ngoh, Lek Heng

    2002-08-01

    An experimental study of the Resilient Packet Ring (RPR) media access control (MAC) technology that is optimized for IP traffic in the metropolitan-area-network (MAN) environment is described. The study involved the deployment and trials of a RPR testbed encompassing a public optical fiber infrastructure in which Cisco Systems' Dynamic Packet Transport (DPT) Ring Technology - a prestandard RPR implementation - was used. We focus on a number of important RPR protocol features that are vital to the future success of RPR as a MAN/wide-area-network (WAN) network technology. Related research on RPR/DPT has been done so far through simulation studies only. Standardization of RPR is currently being performed by the Institute of Electrical and Electronics Engineers (IEEE) 802.17 working group and is expected to be completed in 2003. Also, we present and discuss the experiments and tests performed to investigate the key features of RPR, along with the results obtained.

  2. Transmission Delay Modeling of Packet Communication over Digital Subscriber Line

    Directory of Open Access Journals (Sweden)

    Jiri Vodrazka

    2013-01-01

    Full Text Available Certain multimedia and voice services, such as VoIP, IPTV, etc., are significantly delay sensitive and their performance is influenced by the overall transmission delay and its variance. One of the most common solutions used in access networks are xDSL lines, especially ADSL2+ or VDSL2. Although these subscriber lines also use packet communication, there are several differences and mechanisms, which influence their resulting delay. Their delay characteristics are also dependent on the individual settings of each xDSL provider, therefore we decided to investigate this area for typical commercially available lines in Czech Republic. Based on the measured values and experiments with real ADSL2+ lines we also developed a potential modeling method, which is presented in this article as well. The parameters for packet jitter based on the generalized Pareto distribution were modeled.

  3. Cherenkov Radiation Control via Self-accelerating Wave-packets.

    Science.gov (United States)

    Hu, Yi; Li, Zhili; Wetzel, Benjamin; Morandotti, Roberto; Chen, Zhigang; Xu, Jingjun

    2017-08-18

    Cherenkov radiation is a ubiquitous phenomenon in nature. It describes electromagnetic radiation from a charged particle moving in a medium with a uniform velocity larger than the phase velocity of light in the same medium. Such a picture is typically adopted in the investigation of traditional Cherenkov radiation as well as its counterparts in different branches of physics, including nonlinear optics, spintronics and plasmonics. In these cases, the radiation emitted spreads along a "cone", making it impractical for most applications. Here, we employ a self-accelerating optical pump wave-packet to demonstrate controlled shaping of one type of generalized Cherenkov radiation - dispersive waves in optical fibers. We show that, by tuning the parameters of the wave-packet, the emitted waves can be judiciously compressed and focused at desired locations, paving the way to such control in any physical system.

  4. Time-series analysis of vibrational nuclear wave packet dynamics

    Science.gov (United States)

    Thumm, Uwe; Niederhausen, Thomas; Feuerstein, Bernold

    2008-10-01

    We discuss the extent to which measured time-dependent fragment kinetic energy release (KER) spectra and calculated nuclear probability densities can reveal 1) the transition frequencies between stationary vibrational states, 2) the nodal structure of stationary vibrational states, 3) the ground-state adiabatic electronic potential curve of the molecular ion, and 4) the progression of decoherence induced by random interactions with the environment. We illustrate our discussion with numerical simulations for the time-dependent nuclear motion of vibrational wave packets in the D2^+ molecular ion caused by the ionization of its neutral D2 parent molecule with an intense pump laser pulse. Based on a harmonic time-series analysis, we suggest a general scheme for the full reconstruction, up to an overall phase factor, of the initial wave packets based on measured KER spectra, cf., Phys. Rev. A 77, 063401 (2008).

  5. Back-reaction of perturbation wave packets on gray solitons

    Science.gov (United States)

    Walczak, P. B.; Anglin, J. R.

    2012-07-01

    Within the Bogoliubov-de Gennes linearization theory of quantum or classical perturbations around a background solution to the one-dimensional nonlinear Schrödinger equation, we study the back-reaction of wave-packet perturbations on a gray-soliton background. From our recently published exact solutions, we determine that a wave packet effectively jumps ahead as it passes through a soliton, emerging with a wavelength-dependent forward translation in comparison to its motion in absence of the soliton. From this and from the full theory's exact momentum conservation, we deduce that post-Bogoliubov back-reaction must include a commensurate forward advance by the soliton itself. We quantify this effect with a simple theory, and confirm that it agrees with full numerical solution of the classical nonlinear Schrödinger equation. We briefly discuss the implications of this effect for quantum behavior of solitons in quasicondensed dilute gases at finite temperature.

  6. Service Time Analysis for Secondary Packet Transmission with Adaptive Modulation

    KAUST Repository

    Wang, Wen-Jing

    2017-05-12

    Cognitive radio communications can opportunistically access underutilized spectrum for emerging wireless applications. With interweave cognitive implementation, secondary user transmits only if primary user does not occupy the channel and waits for transmission otherwise. Therefore, secondary packet transmission involves both transmission time and waiting time. The resulting extended delivery time (EDT) is critical to the throughput analysis of secondary system. In this paper, we study the EDT of secondary packet transmission with adaptive modulation under interweave implementation to facilitate the delay and throughput analysis of such cognitive radio system. In particular, we propose an analytical framework to derive the probability density functions of EDT considering random-length transmission and waiting slots. We also present selected numerical results to illustrate the mathematical formulations and to verify our analytical approach.

  7. Predictive onboard flow control in packet switching satellites

    Science.gov (United States)

    Bobinsky, E. A.

    1992-01-01

    We outline two alternate approaches to predicting the onset of congestion in a packet switching satellite, and argue that predictive, rather than reactive, flow control is necessary for the efficient operation of such a system. The first method discussed is based on standard, statistical techniques which are used to periodically calculate a probability of near-term congestion based on arrival rate statistics. If this probability exceeds a present threshold, the satellite would transmit a rate-reduction signal to all active ground stations. The second method discussed would utilize a neural network to periodically predict the occurrence of buffer overflow based on input data which would include, in addition to arrival rates, the distributions of packet lengths, source addresses, and destination addresses.

  8. Predictive onboard flow control for packet switching satellites

    Science.gov (United States)

    Bobinsky, Eric A.

    1992-01-01

    We outline two alternate approaches to predicting the onset of congestion in a packet switching satellite, and argue that predictive, rather than reactive, flow control is necessary for the efficient operation of such a system. The first method discussed is based on standard, statistical techniques which are used to periodically calculate a probability of near-term congestion based on arrival rate statistics. If this probability exceeds a present threshold, the satellite would transmit a rate-reduction signal to all active ground stations. The second method discussed would utilize a neural network to periodically predict the occurrence of buffer overflow based on input data which would include, in addition to arrival rates, the distributions of packet lengths, source addresses, and destination addresses.

  9. SARA - SURE/ASSIST RELIABILITY ANALYSIS WORKSTATION (UNIX VERSION)

    Science.gov (United States)

    Butler, R. W.

    1994-01-01

    SARA, the SURE/ASSIST Reliability Analysis Workstation, is a bundle of programs used to solve reliability problems. The mathematical approach chosen to solve a reliability problem may vary with the size and nature of the problem. The Systems Validation Methods group at NASA Langley Research Center has created a set of four software packages that form the basis for a reliability analysis workstation, including three for use in analyzing reconfigurable, fault-tolerant systems and one for analyzing non-reconfigurable systems. The SARA bundle includes the three for reconfigurable, fault-tolerant systems: SURE reliability analysis program (COSMIC program LAR-13789, LAR-14921); the ASSIST specification interface program (LAR-14193, LAR-14923), and PAWS/STEM reliability analysis programs (LAR-14165, LAR-14920). As indicated by the program numbers in parentheses, each of these three packages is also available separately in two machine versions. The fourth package, which is only available separately, is FTC, the Fault Tree Compiler (LAR-14586, LAR-14922). FTC is used to calculate the top-event probability for a fault tree which describes a non-reconfigurable system. PAWS/STEM and SURE are analysis programs which utilize different solution methods, but have a common input language, the SURE language. ASSIST is a preprocessor that generates SURE language from a more abstract definition. ASSIST, SURE, and PAWS/STEM are described briefly in the following paragraphs. For additional details about the individual packages, including pricing, please refer to their respective abstracts. ASSIST, the Abstract Semi-Markov Specification Interface to the SURE Tool program, allows a reliability engineer to describe the failure behavior of a fault-tolerant computer system in an abstract, high-level language. The ASSIST program then automatically generates a corresponding semi-Markov model. A one-page ASSIST-language description may result in a semi-Markov model with thousands of states and

  10. Mixture block coding with progressive transmission in packet video. Appendix 1: Item 2. M.S. Thesis

    Science.gov (United States)

    Chen, Yun-Chung

    1989-01-01

    Video transmission will become an important part of future multimedia communication because of dramatically increasing user demand for video, and rapid evolution of coding algorithm and VLSI technology. Video transmission will be part of the broadband-integrated services digital network (B-ISDN). Asynchronous transfer mode (ATM) is a viable candidate for implementation of B-ISDN due to its inherent flexibility, service independency, and high performance. According to the characteristics of ATM, the information has to be coded into discrete cells which travel independently in the packet switching network. A practical realization of an ATM video codec called Mixture Block Coding with Progressive Transmission (MBCPT) is presented. This variable bit rate coding algorithm shows how a constant quality performance can be obtained according to user demand. Interactions between codec and network are emphasized including packetization, service synchronization, flow control, and error recovery. Finally, some simulation results based on MBCPT coding with error recovery are presented.

  11. Organizations with Resources Relevant to Addressing Barriers to Student Learning: A Catalogue of Clearinghouses, Technical Assistance Centers, and Other Agencies. A Resource Aid Packet.

    Science.gov (United States)

    California Univ., Los Angeles. Center for Mental Health in Schools.

    This catalogue has been created as part of the UCLA Center for Mental Health in Schools' effort to compile and disseminate a set of resources useful to addressing barriers to student learning. This resource packet categorizes and provides contact information on organizations focusing on children's mental health, education and schools, school-based…

  12. Digital Image Watermarking Algorithm Based on Wavelet Packet

    OpenAIRE

    Geetha, A.; B.Vijayakumari; C.Nagavani; T.Pandiselvi

    2011-01-01

    In this paper, a method for Digital Image Watermarking based on the modification of certain subband of the wavelet packet decomposition was presented. A key is used for wavelet bases selection, watermark generation and selection of blocks for embedding the watermark bits. To efficiently embed the watermark within the images and provide the robustness for the watermark detection under attacks, watermark is embedded by quantizing the mean of the wavelet coefficient block. A method for exploitin...

  13. Effect of latency and packet loss on achievable bandwidth

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    Following an incident with a slow database replication between CERN's data centers, we discovered that even a very low rate packet loss in the network can induce significant penalties to long distance single stream TCP transfers. We explore the behaviour of multiple congestion control algorithms in a controlled loss environment in order to understand what is the achievable throughput of TCP data transfers between the Meyrin and Wigner data centres.

  14. Visualizing picometric quantum ripples of ultrafast wave-packet interference.

    Science.gov (United States)

    Katsuki, Hiroyuki; Chiba, Hisashi; Girard, Bertrand; Meier, Christoph; Ohmori, Kenji

    2006-03-17

    Interference fringes in vibrating molecules are a signature of quantum mechanics, but are often so short-lived and closely spaced that they elude visualization. We have experimentally visualized dynamical quantum interferences, which appear and disappear in less than 100 femtoseconds in the iodine molecule synchronously with the periodic crossing of two counterpropagating nuclear wave packets. The obtained images have picometer and femtosecond spatiotemporal resolution, representing a detailed picture of the quantum interference.

  15. SDN architecture for optical packet and circuit integrated networks

    Science.gov (United States)

    Furukawa, Hideaki; Miyazawa, Takaya

    2016-02-01

    We have been developing an optical packet and circuit integrated (OPCI) network, which realizes dynamic optical path, high-density packet multiplexing, and flexible wavelength resource allocation. In the OPCI networks, a best-effort service and a QoS-guaranteed service are provided by employing optical packet switching (OPS) and optical circuit switching (OCS) respectively, and users can select these services. Different wavelength resources are assigned for OPS and OCS links, and the amount of their wavelength resources are dynamically changed in accordance with the service usage conditions. To apply OPCI networks into wide-area (core/metro) networks, we have developed an OPCI node with a distributed control mechanism. Moreover, our OPCI node works with a centralized control mechanism as well as a distributed one. It is therefore possible to realize SDN-based OPCI networks, where resource requests and a centralized configuration are carried out. In this paper, we show our SDN architecture for an OPS system that configures mapping tables between IP addresses and optical packet addresses and switching tables according to the requests from multiple users via a web interface. While OpenFlow-based centralized control protocol is coming into widespread use especially for single-administrative, small-area (LAN/data-center) networks. Here, we also show an interworking mechanism between OpenFlow-based networks (OFNs) and the OPCI network for constructing a wide-area network, and a control method of wavelength resource selection to automatically transfer diversified flows from OFNs to the OPCI network.

  16. Software For Management Of A Packet-Radio Network

    Science.gov (United States)

    Smyth, Patrick J.; Chauvin, Todd H.; Oliver, Gordon P.; Statman, Joseph I.

    1994-01-01

    Network-management software assists in planning, monitoring, and controlling resources of Datalink network. Packet-message network featuring time-division multiple access, frequency and spatial diversity, and dynamic tree-structured routing scheme. Developed for communication between central control station on ground and instrumented aircraft flying over test range. Aircraft derives navigational data from satellites of Global Positioning System, and primary function of Datalink network feeding GPS position data from participating aircraft into control center in real time.

  17. Multi-threshold de-noising of electrical imaging logging data based on the wavelet packet transform

    Science.gov (United States)

    Xie, Fang; Xiao, Chengwen; Liu, Ruilin; Zhang, Lili

    2017-08-01

    A key problem of effectiveness evaluation for fractured-vuggy carbonatite reservoir is how to accurately extract fracture and vug information from electrical imaging logging data. Drill bits quaked during drilling and resulted in rugged surfaces of borehole walls and thus conductivity fluctuations in electrical imaging logging data. The occurrence of the conductivity fluctuations (formation background noise) directly affects the fracture/vug information extraction and reservoir effectiveness evaluation. We present a multi-threshold de-noising method based on wavelet packet transform to eliminate the influence of rugged borehole walls. The noise is present as fluctuations in button-electrode conductivity curves and as pockmarked responses in electrical imaging logging static images. The noise has responses in various scales and frequency ranges and has low conductivity compared with fractures or vugs. Our de-noising method is to decompose the data into coefficients with wavelet packet transform on a quadratic spline basis, then shrink high-frequency wavelet packet coefficients in different resolutions with minimax threshold and hard-threshold function, and finally reconstruct the thresholded coefficients. We use electrical imaging logging data collected from fractured-vuggy Ordovician carbonatite reservoir in Tarim Basin to verify the validity of the multi-threshold de-noising method. Segmentation results and extracted parameters are shown as well to prove the effectiveness of the de-noising procedure.

  18. Multifocal ERG wavelet packet decomposition applied to glaucoma diagnosis

    Directory of Open Access Journals (Sweden)

    Rodríguez-Ascariz José M

    2011-05-01

    Full Text Available Abstract Background Glaucoma is the second-leading cause of blindness worldwide and early diagnosis is essential to its treatment. Current clinical methods based on multifocal electroretinography (mfERG essentially involve measurement of amplitudes and latencies and assume standard signal morphology. This paper presents a new method based on wavelet packet analysis of global-flash multifocal electroretinogram signals. Methods This study comprised twenty-five patients diagnosed with OAG and twenty-five control subjects. Their mfERG recordings data were used to develop the algorithm method based on wavelet packet analysis. By reconstructing the third wavelet packet contained in the fourth decomposition level (ADAA4 of the mfERG recording, it is possible to obtain a signal from which to extract a marker in the 60-80 ms time interval. Results The marker found comprises oscillatory potentials with a negative-slope basal line in the case of glaucomatous recordings and a positive-slope basal line in the case of normal signals. Application of the optimal threshold calculated in the validation cases showed that the technique proposed achieved a sensitivity of 0.81 and validation specificity of 0.73. Conclusions This new method based on mfERG analysis may be reliable enough to detect functional deficits that are not apparent using current automated perimetry tests. As new stimulation and analysis protocols develop, mfERG has the potential to become a useful tool in early detection of glaucoma-related functional deficits.

  19. The effect of human rhythm on packet delivery

    Science.gov (United States)

    Zhou, Zhao; Huang, Zi-Gang; Yang, Lei; Xue, De-Sheng; Wang, Ying-Hai

    2010-08-01

    In communication networks such as the Internet, the relationship between packet generation rate and time is similar to a rectangle wavefunction due to the rhythm of humans. Thus, we investigate the traffic dynamics on a network with a rectangle wavepacket generation rate. It is found that the critical delivering capacity parameter βc (which separates the congested phase and the free phase) decreases significantly with the duty cycle r of the rectangle wave for package generation. And, in the congested phase, more collective generation of packets (smaller r) is helpful for decreasing the packet aggregation rate. Moreover, it is found that the congested phase can be divided into two regions, i.e., region 1 and region 2, where the distributions of queue lengths are nonlinear and linear, respectively. Also, the linear expression for the distribution of queue lengths in region 2 is obtained analytically. Our work reveals an obvious effect of the rectangle wave on the traffic dynamics and the queue length distribution in the system, which is of essential interest and may provide insights into the designing of work-rest schedules and routing strategies.

  20. Characteristics of vortex packets in a boundary layer

    Science.gov (United States)

    Ganapathisubramani, Bharathram; Longmire, Ellen; Marusic, Ivan

    2002-11-01

    Stereo PIV was used to measure all three velocity components in streamwise-spanwise (x-y) planes of a turbulent boundary layer at Re_τ = 1060. Datasets were obtained in the log layer and beyond. The vector fields in the log layer (z^+ = 92 and 150, z - wall normal direction) revealed signatures of vortex packets similar to those found by Adrian and co-workers in their PIV experiments. Groups of legs of hairpin vortices appeared to be coherently arranged along the x direction. These regions also generated substantial Reynolds shear stress (-uw), sometimes as high as 40U_τ^2. A feature extraction algorithm was developed to automate the identification and characterization of these packets of hairpin vortices. Identified patches contributed 28% to the total -uw while occupying less than 5% of the total area in the log layer. Beyond the log layer (z^+ = 198, 530), the spatial organization into packets breaks down. Instead, large individual vortex cores and spanwise strips of positive and negative wall-normal velocity were observed. Supported by NSF (ACI-9982774, CTS-9983933).

  1. Recovery of vortex packet organization in perturbed turbulent boundary layers

    Science.gov (United States)

    Tan, Yan Ming; Longmire, Ellen K.

    2017-10-01

    Turbulent boundary layers with R eτ=2500 were perturbed by an array of cylinders projecting outward from the wall, and the flow organization downstream was investigated at multiple measurement heights in the logarithmic region. Two array heights were considered: H =0.2 δ , extending through the log region and H =δ , extending to the top of the boundary layer. Results from instantaneous PIV in wall-parallel planes and a vortex packet identification algorithm clearly showed a bottom-up mechanism for packet recovery downstream of the H =δ array, even though streamwise velocity statistics remained strongly perturbed. In contrast, some indications of top-down recovery were observed for the flow perturbed by the shorter H =0.2 δ (H+=500 ) array. In this case, however, packet structures closer to the wall at z+=125 remained altered beyond the end of the measurement domain 7δ downstream of the cylinders even though streamwise velocity statistics relaxed nearly to the unperturbed values.

  2. Characteristics of vortex packets in turbulent boundary layers

    Science.gov (United States)

    Ganapathisubramani, Bharathram; Longmire, Ellen K.; Marusic, Ivan

    2003-03-01

    Stereoscopic particle image velocimetry (PIV) was used to measure all three instantaneous components of the velocity field in streamwise spanwise planes of a turbulent boundary layer at Re[tau]=1060 (Re[theta]=2500). Datasets were obtained in the logarithmic layer and beyond. The vector fields in the log layer (z+=92 and 150) revealed signatures of vortex packets similar to those proposed by Adrian and co-workers in their PIV experiments. Groups of legs of hairpin vortices appeared to be coherently arranged in the streamwise direction. These regions also generated substantial Reynolds shear stress, sometimes as high as 40 times [minus sign]uw. A feature extraction algorithm was developed to automate the identification and characterization of these packets of hairpin vortices. Identified patches contributed 28% to [minus sign]uw while occupying only 4% of the total area at z+=92. At z+=150, these patches occupied 4.5% of the total area while contributing 25% to [minus sign]uw. Beyond the log layer (z+=198 and 530), the spatial organization into packets is seen to break down.

  3. Efficient incremental relaying for packet transmission over fading channels

    KAUST Repository

    Fareed, Muhammad Mehboob

    2014-07-01

    In this paper, we propose a novel relaying scheme for packet transmission over fading channels, which improves the spectral efficiency of cooperative diversity systems by utilizing limited feedback from the destination. Our scheme capitalizes on the fact that relaying is only required when direct transmission suffers deep fading. We calculate the packet error rate for the proposed efficient incremental relaying (EIR) scheme with both amplify and forward and decode and forward relaying. We compare the performance of the EIR scheme with the threshold-based incremental relaying (TIR) scheme. It is shown that the efficiency of the TIR scheme is better for lower values of the threshold. However, the efficiency of the TIR scheme for higher values of threshold is outperformed by the EIR. In addition, three new threshold-based adaptive EIR are devised to further improve the efficiency of the EIR scheme. We calculate the packet error rate and the efficiency of these new schemes to provide the analytical insight. © 2014 IEEE.

  4. The performance analysis of linux networking - packet receiving

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Wenji; Crawford, Matt; Bowden, Mark; /Fermilab

    2006-11-01

    The computing models for High-Energy Physics experiments are becoming ever more globally distributed and grid-based, both for technical reasons (e.g., to place computational and data resources near each other and the demand) and for strategic reasons (e.g., to leverage equipment investments). To support such computing models, the network and end systems, computing and storage, face unprecedented challenges. One of the biggest challenges is to transfer scientific data sets--now in the multi-petabyte (10{sup 15} bytes) range and expected to grow to exabytes within a decade--reliably and efficiently among facilities and computation centers scattered around the world. Both the network and end systems should be able to provide the capabilities to support high bandwidth, sustained, end-to-end data transmission. Recent trends in technology are showing that although the raw transmission speeds used in networks are increasing rapidly, the rate of advancement of microprocessor technology has slowed down. Therefore, network protocol-processing overheads have risen sharply in comparison with the time spent in packet transmission, resulting in degraded throughput for networked applications. More and more, it is the network end system, instead of the network, that is responsible for degraded performance of network applications. In this paper, the Linux system's packet receive process is studied from NIC to application. We develop a mathematical model to characterize the Linux packet receiving process. Key factors that affect Linux systems network performance are analyzed.

  5. Cognitive function during low-intensity walking: a test of the treadmill workstation.

    Science.gov (United States)

    Alderman, Brandon L; Olson, Ryan L; Mattina, Diana M

    2014-05-01

    The purpose of this study was to examine the effects of walking at self-selected speed on an active workstation on cognitive performance. Sixty-six participants (n = 27 males, 39 females; mean age = 21.06 ± 1.6 years) completed a treadmill-desk walking and a seated control condition, separated by 48 hours. During each condition, participants completed computerized versions of the Stroop test, a modified flanker task, and a test of reading comprehension. No significant differences in response speed or accuracy were found between walking and sitting conditions for any the cognitive tests. These findings reveal that performance on cognitive tasks, including executive control processes, are not impaired by walking on an active workstation. Implementing active workstations into offices and classrooms may help to decrease sedentariness without impairing task performance.

  6. A study of workstation computational performance for real-time flight simulation

    Science.gov (United States)

    Maddalon, Jeffrey M.; Cleveland, Jeff I., II

    1995-01-01

    With recent advances in microprocessor technology, some have suggested that modern workstations provide enough computational power to properly operate a real-time simulation. This paper presents the results of a computational benchmark, based on actual real-time flight simulation code used at Langley Research Center, which was executed on various workstation-class machines. The benchmark was executed on different machines from several companies including: CONVEX Computer Corporation, Cray Research, Digital Equipment Corporation, Hewlett-Packard, Intel, International Business Machines, Silicon Graphics, and Sun Microsystems. The machines are compared by their execution speed, computational accuracy, and porting effort. The results of this study show that the raw computational power needed for real-time simulation is now offered by workstations.

  7. Multimodal optical workstation for simultaneous linear, nonlinear microscopy and nanomanipulation: upgrading a commercial confocal inverted microscope.

    Science.gov (United States)

    Mathew, Manoj; Santos, Susana I C O; Zalvidea, Dobryna; Loza-Alvarez, Pablo

    2009-07-01

    In this work we propose and build a multimodal optical workstation that extends a commercially available confocal microscope (Nikon Confocal C1-Si) to include nonlinear/multiphoton microscopy and optical manipulation/stimulation tools such as nanosurgery. The setup allows both subsystems (confocal and nonlinear) to work independently and simultaneously. The workstation enables, for instance, nanosurgery along with simultaneous confocal and brightfield imaging. The nonlinear microscopy capabilities are added around the commercial confocal microscope by exploiting all the flexibility offered by this microscope and without need for any mechanical or electronic modification of the confocal microscope systems. As an example, the standard differential interference contrast condenser and diascopic detector in the confocal microscope are readily used as a forward detection mount for second harmonic generation imaging. The various capabilities of this workstation, as applied directly to biology, are demonstrated using the model organism Caenorhabditis elegans.

  8. SESSION – PACKET INSPECTOR MOBILE AGENT TO PREVENT ENCRYPTED COOKIES AND HTTP POST HIJACKING IN MANET

    Directory of Open Access Journals (Sweden)

    ARUN V.

    2016-12-01

    Full Text Available A statistics states that public Wi-Fi hotspots are set to grow from 1.3 million in 2011 to 5.8 million by 2015. Due to increase in public free Wi-Fi access, userscount increases rapidly letting them to expose in vulnerable intrusion attacks. Accessing the social network and other confidential sites such as banking in public Wi-Fi, exposes the credential to the intruder. Man-in-the-middle attack plays a major role in accessing the user credential. Analysing the packets exposes the HTTP post information in the network. Capturing encrypted cookies by the man-in-the-middle can access the secure site and allows the intruder to be an authorized person. Mobile agent is a piece of code that migrates and performs actions in the host and is used to prevent intrusion. We propose a model to prevent intrusion in the wireless ad-hoc network using mobile agent. Session-Packet inspector is proposed to handle HTTP post hijacking and encrypted cookie usage by the intruder.

  9. Coherent structural trapping through wave packet dispersion during photoinduced spin state switching

    Science.gov (United States)

    Lemke, Henrik T.; Kjær, Kasper S.; Hartsock, Robert; van Driel, Tim B.; Chollet, Matthieu; Glownia, James M.; Song, Sanghoon; Zhu, Diling; Pace, Elisabetta; Matar, Samir F.; Nielsen, Martin M.; Benfatto, Maurizio; Gaffney, Kelly J.; Collet, Eric; Cammarata, Marco

    2017-01-01

    The description of ultrafast nonadiabatic chemical dynamics during molecular photo-transformations remains challenging because electronic and nuclear configurations impact each other and cannot be treated independently. Here we gain experimental insights, beyond the Born–Oppenheimer approximation, into the light-induced spin-state trapping dynamics of the prototypical [Fe(bpy)3]2+ compound by time-resolved X-ray absorption spectroscopy at sub-30-femtosecond resolution and high signal-to-noise ratio. The electronic decay from the initial optically excited electronic state towards the high spin state is distinguished from the structural trapping dynamics, which launches a coherent oscillating wave packet (265 fs period), clearly identified as molecular breathing. Throughout the structural trapping, the dispersion of the wave packet along the reaction coordinate reveals details of intramolecular vibronic coupling before a slower vibrational energy dissipation to the solution environment. These findings illustrate how modern time-resolved X-ray absorption spectroscopy can provide key information to unravel dynamic details of photo-functional molecules. PMID:28537270

  10. Coherent structural trapping through wave packet dispersion during photoinduced spin state switching

    Science.gov (United States)

    Lemke, Henrik T.; Kjær, Kasper S.; Hartsock, Robert; van Driel, Tim B.; Chollet, Matthieu; Glownia, James M.; Song, Sanghoon; Zhu, Diling; Pace, Elisabetta; Matar, Samir F.; Nielsen, Martin M.; Benfatto, Maurizio; Gaffney, Kelly J.; Collet, Eric; Cammarata, Marco

    2017-05-01

    The description of ultrafast nonadiabatic chemical dynamics during molecular photo-transformations remains challenging because electronic and nuclear configurations impact each other and cannot be treated independently. Here we gain experimental insights, beyond the Born-Oppenheimer approximation, into the light-induced spin-state trapping dynamics of the prototypical [Fe(bpy)3]2+ compound by time-resolved X-ray absorption spectroscopy at sub-30-femtosecond resolution and high signal-to-noise ratio. The electronic decay from the initial optically excited electronic state towards the high spin state is distinguished from the structural trapping dynamics, which launches a coherent oscillating wave packet (265 fs period), clearly identified as molecular breathing. Throughout the structural trapping, the dispersion of the wave packet along the reaction coordinate reveals details of intramolecular vibronic coupling before a slower vibrational energy dissipation to the solution environment. These findings illustrate how modern time-resolved X-ray absorption spectroscopy can provide key information to unravel dynamic details of photo-functional molecules.

  11. PARALLEL QUICK SEARCH ALGORITHM TO SPEED PACKET PAYLOAD FILTERING IN NIDS

    Directory of Open Access Journals (Sweden)

    ADNAN A. HNAIF

    2009-06-01

    Full Text Available An Intrusion Detection System (IDS is a system to detect intruders who try to hack in to the network and steal information and report them to the network administrator. There are many tools used in this field, snort consider one of the most tools mostly used in Network Intrusion Detection System (NIDS. In spite of consuming 31% of total processing due to string matching, and 80% of total processing in case of web-intensive traffic, snort using its rule sets to determine which packets are allowed to pass and which are rejected. In this paper, we parallelized the quick search algorithm using OpenMP and Pthread (Posix using C language and made a comparison between them; we determine the required number of threads according to many factors. By doing this, we managed to speed up the filtering process for more than 40% and finally. We applied the proposed method into NIDS to enhance the speed of matching process between incoming packet contents and snort rule sets.

  12. Sampled-Data Consensus of Linear Multi-agent Systems With Packet Losses.

    Science.gov (United States)

    Zhang, Wenbing; Tang, Yang; Huang, Tingwen; Kurths, Jurgen

    In this paper, the consensus problem is studied for a class of multi-agent systems with sampled data and packet losses, where random and deterministic packet losses are considered, respectively. For random packet losses, a Bernoulli-distributed white sequence is used to describe packet dropouts among agents in a stochastic way. For deterministic packet losses, a switched system with stable and unstable subsystems is employed to model packet dropouts in a deterministic way. The purpose of this paper is to derive consensus criteria, such that linear multi-agent systems with sampled-data and packet losses can reach consensus. By means of the Lyapunov function approach and the decomposition method, the design problem of a distributed controller is solved in terms of convex optimization. The interplay among the allowable bound of the sampling interval, the probability of random packet losses, and the rate of deterministic packet losses are explicitly derived to characterize consensus conditions. The obtained criteria are closely related to the maximum eigenvalue of the Laplacian matrix versus the second minimum eigenvalue of the Laplacian matrix, which reveals the intrinsic effect of communication topologies on consensus performance. Finally, simulations are given to show the effectiveness of the proposed results.In this paper, the consensus problem is studied for a class of multi-agent systems with sampled data and packet losses, where random and deterministic packet losses are considered, respectively. For random packet losses, a Bernoulli-distributed white sequence is used to describe packet dropouts among agents in a stochastic way. For deterministic packet losses, a switched system with stable and unstable subsystems is employed to model packet dropouts in a deterministic way. The purpose of this paper is to derive consensus criteria, such that linear multi-agent systems with sampled-data and packet losses can reach consensus. By means of the Lyapunov function

  13. Synchronization, retiming and time-division multiplexing of an asynchronous 10 gigabit NRZ Ethernet packet to Terabit Ethernet

    DEFF Research Database (Denmark)

    Hu, Hao; Laguardia Areal, Janaina; Mulvad, Hans Christian Hansen

    2011-01-01

    An asynchronous 10 Gb/s Ethernet packet with maximum packet size of 1518 bytes is synchronized and retimed to a master clock with 200 kHz frequency offset using a time lens. The NRZ packet is simultaneously converted into an RZ packet, then further pulse compressed to a FWHM of 400 fs and finally....../s of the Ethernet packet is achieved. © 2011 Optical Society of America....

  14. Derivative-Free Distributed Filtering for MIMO Robotic Systems under Delays and Packet Drops

    Directory of Open Access Journals (Sweden)

    Gerasimos G. Rigatos

    2013-02-01

    Full Text Available This paper presents an approach to distributed state estimation-based control of nonlinear MIMO systems, capable of incorporating delayed measurements in the estimation algorithm while also being robust to packet losses. First, the paper examines the problem of distributed nonlinear filtering over a communication/sensors network, and the use of the estimated state vector in a control loop. As a possible filtering approach, an extended information filter (EIF is proposed. The extended information filter requires the computation of Jacobians which in the case of high order nonlinear dynamical systems can be a cumbersome procedure, while it also introduces cumulative errors to the state estimation due to the approximative linearization performed in the Taylor series expansion of the system's nonlinear model. To overcome the aforementioned weaknesses of the extended information filter, a derivative-free approach to extended information filtering has been proposed. Distributed filtering is now based on a derivative-free implementation of Kalman filtering which is shown to be applicable to MIMO nonlinear dynamical systems. In the proposed derivative-free extended information filtering, the system is first subject to a linearization transformation that makes use of the differential flatness theory. It is shown how the proposed distributed filtering method can succeed in compensation of random delays and packet drops which may appear during the transmission of measurements and of state vector estimates, thus assuring a reliable performance of the distributed filtering-based control scheme. Evaluation tests are carried out on benchmark MIMO nonlinear systems, such as multi-DOF robotic manipulators.

  15. Accuracy of apparent diffusion coefficient value measurement on PACS workstation: A comparative analysis.

    Science.gov (United States)

    El Kady, Reem M; Choudhary, Arabinda Kumar; Tappouni, Rafel

    2011-03-01

    The purpose of this article is to evaluate the accuracy of apparent diffusion coefficient (ADC) measurements made with a PACS workstation compared with measurements made with a dedicated workstation, which is currently considered the reference standard. A retrospective review was performed in liver lesions from 79 patients using three MRI platforms. The final diagnosis was established by liver biopsy in 31 patients and by dynamic MRI and follow-up, both clinical and radiologic as indicated, in 48 patients. Each lesion that was clearly demonstrable on the ADC map was measured with a commercial dedicated postprocessing workstation and again with a PACS system. A two-sample t test was used to determine the statistically significant differences between the two ADC measurements. A total of 79 patients with 120 liver lesions were included. ADC values measured on the workstation were 0.4-4.38 × 10(-3) mm(2)/s. The ADC values measured on the PACS were 0.42-4.35 × 10(-3) mm(2)/s. The T value was -1.113, with 119 degrees of freedom, and the significance level was 0.268, which implies no significant difference between the two different measuring systems for all pathologic abnormalities and MRI scanners used. ADC values measured on a routine PACS workstation are as accurate as the values obtained on a dedicated specialized workstation. ADC value measurement on the routine PACS will save time and lead to increased utilization, which, in turn, will lead to an improved understanding of the different disease processes and their clinical management.

  16. Tracking an electronic wave packet in the vicinity of a conical intersection

    Science.gov (United States)

    Qi, Da-Long; Duan, Hong-Guang; Sun, Zhen-Rong; Miller, R. J. Dwayne; Thorwart, Michael

    2017-08-01

    This work treats the impact of vibrational coherence on the quantum efficiency of a dissipative electronic wave packet in the vicinity of a conical intersection by monitoring the time-dependent wave packet projection onto the tuning and the coupling mode. The vibrational coherence of the wave packet is tuned by varying the strength of the dissipative vibrational coupling of the tuning and the coupling modes to their thermal baths. We observe that the most coherent wave packet yields a quantum efficiency of 93%, but with a large transfer time constant. The quantum yield is dramatically decreased to 50% for a strongly damped incoherent wave packet, but the associated transfer time of the strongly localized wave packet is short. In addition, we find for the strongly damped wave packet that the transfer occurs via tunneling of the wave packet between the potential energy surfaces before the seam of the conical intersection is reached and a direct passage takes over. Our results provide direct evidence that vibrational coherence of the electronic wave packet is a decisive factor which determines the dynamical behavior of a wave packet in the vicinity of the conical intersection.

  17. Palletizing system of packets containing confectionery materials; Kashi zairyo backet paretaizu system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-02-29

    A palletizing system of packets containing confectionery materials was manufactured and delivered (Figure 11). The three-step loaded packets on which the confectionery materials carried out from the preceding process were put are positioned on the tip conveyor. These packets are then sequentially taken out from the upper packet and transferred to an empty pallet. The step-loaded packets are easy to shift from the position, so a special hand that allows the position shift was applied. For the step loading of packets, the special relief mechanism and push-in operation of a hook are used so that the clearance between packets does not occur. The packet dimensions are about 500 x 350 x 380 mm (W/H/D). The maximum weight is about 30 kg. A pallet is made of resin. Five packets in five steps are loaded on one pallet. The main configuration of this system is as follows: (1) Palletizer (VPR-800) x 1. (2) Controller (meirocs-G) x 1. (3) Packet catch-only hand x 1. (4) Tip conveyor x 1. (5) Safety fence. (translated by NEDO)

  18. BioPhotonics Workstation: 3D interactive manipulation, observation and characterization

    DEFF Research Database (Denmark)

    Glückstad, Jesper

    2011-01-01

    In ppo.dk we have invented the BioPhotonics Workstation to be applied in 3D research on regulated microbial cell growth including their underlying physiological mechanisms, in vivo characterization of cell constituents and manufacturing of nanostructures and new materials.......In ppo.dk we have invented the BioPhotonics Workstation to be applied in 3D research on regulated microbial cell growth including their underlying physiological mechanisms, in vivo characterization of cell constituents and manufacturing of nanostructures and new materials....

  19. Workstation allows engineers to design state-of-the-art plants

    Energy Technology Data Exchange (ETDEWEB)

    Sopocy, D.M.; Stenzel, W.C.; Kalinik, J.B.; Tokarski, T.A. (Sargent and Lundy, Chicago, IL (United States)); Pace, S.E. (Electric Power Research Institute, Palo Alto, CA (United States))

    1993-03-01

    This article reviews the development of a workstation for computer-aided design and simulation of state-of-the-art power plants. The topics of the article include the project team, technology guideline modules, conceptual designs, workstation design, innovative software technologies, and typical guideline module. The advanced technologies being addressed by the project are appropriate for a wide range of fuels and power technologies. They include advanced pulverized coal-fired plants, combustion turbines, combined-cycle, and circulating fluidized-bed combustion plants.

  20. Analysis on the influence of supply method on a workstation with the help of dynamic simulation

    Directory of Open Access Journals (Sweden)

    Gavriluță Alin

    2017-01-01

    Full Text Available Considering the need of flexibility in any manufacturing process, the choice of the supply method of an assembly workstation can be a decision with instead influence on its performances. Using dynamic simulation, this article wants to compare the effect on a workstation cycle time of three different supply methods: supply on stock, supply in “Strike Zone” and synchronous supply. This study is part of an extended work that has the aim of compering by 3D layout design and dynamic simulation, different supply methods on an assembly line performances.

  1. Five-wave-packet quantum error correction based on continuous-variable cluster entanglement.

    Science.gov (United States)

    Hao, Shuhong; Su, Xiaolong; Tian, Caixing; Xie, Changde; Peng, Kunchi

    2015-10-26

    Quantum error correction protects the quantum state against noise and decoherence in quantum communication and quantum computation, which enables one to perform fault-torrent quantum information processing. We experimentally demonstrate a quantum error correction scheme with a five-wave-packet code against a single stochastic error, the original theoretical model of which was firstly proposed by S. L. Braunstein and T. A. Walker. Five submodes of a continuous variable cluster entangled state of light are used for five encoding channels. Especially, in our encoding scheme the information of the input state is only distributed on three of the five channels and thus any error appearing in the remained two channels never affects the output state, i.e. the output quantum state is immune from the error in the two channels. The stochastic error on a single channel is corrected for both vacuum and squeezed input states and the achieved fidelities of the output states are beyond the corresponding classical limit.

  2. Effectiveness of the Interactive Videodisc Workstation in Use in the English Language Center at Brigham Young University.

    Science.gov (United States)

    Branvold, Dwight; And Others

    1986-01-01

    Assessment of the effectiveness of workstations teaching English-as-a-second-language content, vocabulary, and idiomatic expressions through an adventure film found that the workstations were highly motivational and stimulating, while their effectiveness depended on the students' individual learning styles. (Author/CB)

  3. Comparisons of musculoskeletal complaints and data entry between a sitting and a sit-stand workstation paradigm.

    Science.gov (United States)

    Husemann, Britta; Von Mach, Carolin Yvonne; Borsotto, Daniel; Zepf, Kirsten Isabel; Scharnbacher, Jutta

    2009-06-01

    Seated working positions are often regarded as a cause for discomfort in the musculoskeletal system. Performing work in different working positions--that is, alternating between sitting and standing (sit-stand workstation paradigm)--could help reduce physical complaints. The questions were whether performing office work partly in a standing position leads to reduced complaints and whether standing would change the efficiency of data entry office work. We investigated the effect of a sit-stand workstation paradigmd during experimental data entry office work on physical and psychological complaints and data entry efficiency by conducting a randomized controlled trial with 60 male participants ages 18 to 35 years. In this experiment, musculoskeletal complaints were reduced by a sit-stand workstation paradigm. A trend could be identified indicating a small but nonsignificant loss of efficiency in data entry while standing. A sit-stand workstation paradigm reduces musculoskeletal complaints without considerably affecting data entry efficiency under the presented study conditions (young male participants, short duration, fixed and controlled sit-stand workstation paradigm, simulated experimental working condition). According to the present data, implementing a sit-stand workstation paradigm can be an effective workplace health intervention to reduce musculoskeletal complaints. This experiment encourages further studies on the effectiveness of a sit-stand workstation paradigm. Experimental research and field studies that prove the reduction of complaints when introducing a sit-stand workstation paradigm in the workplace could be the basis for evidence-based recommendations regarding such interventions.

  4. The relationship between musculoskeletal symptoms, postures and the fit between workers' anthropometrics and their computer workstation configuration.

    Science.gov (United States)

    Baker, Nancy A; Moehling, Krissy

    2013-01-01

    Awkward postures during computer use are assumed to be related to the fit between the worker and the workstation configuration, with greater mismatches leading to higher levels of musculoskeletal symptoms (MSS). The objective of this study was to examine if chronic MSS of the neck/shoulder, back, and wrist/hands was associated with 1) discrepancies between workstation setups and worker anthropometrics and 2) workers' postures. Secondary analysis on data collected from a randomized controlled cross-over design trial (N=74). Subjects' workstation configurations, baseline levels of MSS, working postures, and anthropometrics were measured. Correlations were completed to determine the association between postures and discrepancies between the worker anthropometrics and workstation configuration. Associations were examined between postures, workstation discrepancies and worker MSS. There were only 3 significant associations between worker posture and MSS, and 3 significant associations between discrepancies in worker/workstation set-up and MSS. The relationship between chronic MSS and the workers computer workstation configuration is multifactorial. While postures and the fit between the worker and workstation may be associated with MSS, other variables need to be explored to better understand the phenomenon.

  5. Physical Watermarking for Securing Cyber-Physical Systems via Packet Drop Injections

    Energy Technology Data Exchange (ETDEWEB)

    Ozel, Omur [Carnegie Mellon Univ., Pittsburgh, PA (United States); Weekrakkody, Sean [Carnegie Mellon Univ., Pittsburgh, PA (United States); Sinopoli, Bruno [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2017-10-23

    Physical watermarking is a well known solution for detecting integrity attacks on Cyber-Physical Systems (CPSs) such as the smart grid. Here, a random control input is injected into the system in order to authenticate physical dynamics and sensors which may have been corrupted by adversaries. Packet drops may naturally occur in a CPS due to network imperfections. To our knowledge, previous work has not considered the role of packet drops in detecting integrity attacks. In this paper, we investigate the merit of injecting Bernoulli packet drops into the control inputs sent to actuators as a new physical watermarking scheme. With the classical linear quadratic objective function and an independent and identically distributed packet drop injection sequence, we study the effect of packet drops on meeting security and control objectives. Our results indicate that the packet drops could act as a potential physical watermark for attack detection in CPSs.

  6. Relay-Assisted Partial Packet Recovery with IDMA Method in CDMA Wireless Network

    CERN Document Server

    Luo, Zhifeng; Wong, Albert Kai-sun; Qiu, Shuisheng

    2010-01-01

    Automatic Repeat Request (ARQ) is an effective technique for reliable transmission of packets in wireless networks. In ARQ, however, only a few erroneous bits in a packet will cause the entire packet to be discarded at the receiver. In this case, it's wasteful to retransmit the correct bit in the received packet. The partial packet recovery only retransmits the unreliable decoded bits in order to increase the throughput of network. In addition, the cooperative transmission based on Interleave-division multiple-access (IDMA) can obtain diversity gains with multiple relays with different locations for multiple sources simultaneously. By exploring the diversity from the channel between relay and destination, we propose a relay-assisted partial packet recovery in CDMA wireless network to improve the performance of throughput. In the proposed scheme, asynchronous IDMA iterative chip-by-chip multiuser detection is utilized as a method of multiple partial recovery, which can be a complementarity in a current CDMA ne...

  7. Multiple-input multiple-output wavelet packet modulation based software-defined radio transceiver design

    OpenAIRE

    Cribbs, Michael R.

    2015-01-01

    Approved for public release; distribution is unlimited In this thesis, a software-defined radio (SDR) transmitter and receiver is developed using GNU Radio. The designed SDR multiplexes orthogonal subcarriers using wavelet packet modulation (WPM). WPM achieves subcarrier orthogonality by employing the inverse discrete wavelet packet transform (IDWPT) for the transmitter and discrete wavelet packet transform (DWPT) for the receiver. Realization concerns for the IDWPT and DWPT are discussed ...

  8. An Experimental Exploration of the Impact of Network-Level Packet Loss on Network Intrusion Detection

    Science.gov (United States)

    2015-08-01

    packet loss is very common on the Internet. The Transmission Control Protocol ( TCP ) is specifically designed to account for general packet loss and uses...normal congestion control behavior”.4 Although generalized packet loss is not the focus of this research because it is assumed that the target and...datasets and generate and validate a general function. 10 6. References 1. Stevens WR. TCP slow start, congestion avoidance, fast retransmit, and

  9. 76 FR 21775 - Notice of Issuance of Final Determination Concerning Certain Office Workstations

    Science.gov (United States)

    2011-04-18

    ...-, and 135-degree connectors for its workstations which permit its customers to shape their office... particle board and then bond to each board a high pressure laminate top, a backer and edge bands. With... their outermost container needs to be marked. LAW AND ANALYSIS: Government Procurement Pursuant to...

  10. Treadmill workstations: the effects of walking while working on physical activity and work performance.

    Directory of Open Access Journals (Sweden)

    Avner Ben-Ner

    Full Text Available We conducted a 12-month-long experiment in a financial services company to study how the availability of treadmill workstations affects employees' physical activity and work performance. We enlisted sedentary volunteers, half of whom received treadmill workstations during the first two months of the study and the rest in the seventh month of the study. Participants could operate the treadmills at speeds of 0-2 mph and could use a standard chair-desk arrangement at will. (a Weekly online performance surveys were administered to participants and their supervisors, as well as to all other sedentary employees and their supervisors. Using within-person statistical analyses, we find that overall work performance, quality and quantity of performance, and interactions with coworkers improved as a result of adoption of treadmill workstations. (b Participants were outfitted with accelerometers at the start of the study. We find that daily total physical activity increased as a result of the adoption of treadmill workstations.

  11. BioPhotonics Workstation supporting 3D joystick-control of microplatforms [invited

    DEFF Research Database (Denmark)

    Tauro, Sandeep; Palima, Darwin; Perch-Nielsen, Ivan R.

    2010-01-01

    of several microtools simultaneously near one single cell. The experiments are performed in our BioPhotonics Workstation with counterpropagating beam geometry. This geometry provides a large manipulation area and allows realtime manipulation or a plurality or traps (euITenl1y 100 independently reconfigurable...

  12. IBIS integrated biological imaging system: electron micrograph image-processing software running on Unix workstations.

    Science.gov (United States)

    Flifla, M J; Garreau, M; Rolland, J P; Coatrieux, J L; Thomas, D

    1992-12-01

    'IBIS' is a set of computer programs concerned with the processing of electron micrographs, with particular emphasis on the requirements for structural analyses of biological macromolecules. The software is written in FORTRAN 77 and runs on Unix workstations. A description of the various functions and the implementation mode is given. Some examples illustrate the user interface.

  13. Touch-typing VDU operation: workstation adjustment, working posture, and workers' perceptions

    NARCIS (Netherlands)

    Delleman, N.J.; Berndsen, M.B.

    2002-01-01

    At a VDU workstation professional touch-typing operators worked at eight different combined adjustments of visual target height and chair backrest inclination. Working posture, workers' perceptions and work performance were measured. Two conclusions were drawn. First, in order to minimize the load

  14. Sewing machine operation : workstation adjustment, working posture, and workers’ perceptions

    NARCIS (Netherlands)

    Delleman, N.J.; Dul, J.

    2002-01-01

    At a traditional sewing machine workstation professional operators worked at ten different combined adjustments of table height, desk slope, and pedal position. Working posture and workers’ perceptions were measured. Two recommendations were formulated in order to minimize the load on the

  15. [Study on the feasibility of human papilloma virus subtypes detection by automatic nucleic acid extraction workstation].

    Science.gov (United States)

    Zhang, Rui; Ye, Ali; Dou, Yaling; Gan, Yong; Kong, Lingjun; Chen, Yu; Xu, Yingchun

    2015-12-08

    To verify the feasibility of human papilloma virus(HPV) subtypes detection by AUTRAX automatic nucleic acid extraction workstation. A total of 183 HPV test samples (2 562 types) were collected during August 2014 in Peking Union Medical College Hospital. Nucleic acid determination kit of high-risk HPV types (16, 18, 35, 39, 58, 31, 33, 68, 56, 45, 59, 51, 52) and 6 , 11 type (real-time PCR) were applied for detection. Each sample was divided into two parts. One part was treated with manual extraction, which entailed manually preparing PCR reaction system and added the sample to the PCR plate. Another was treated with the AUTRAX automatic nucleic acid extraction workstation, which automatically prepared the reaction system and added to the PCR board. These two parts proceeded to the real-time PCR detection. The result of manual extraction was set as the golden standard and the Kappa consistency analysis was conducted. Meanwhile, precision and pollution prevention of the AUTRAX were verified. The sensitivity of AUTRAX automatic nucleic acids extraction workstation was 97.12% (101/104). The specificity was 99.51% (2 446/2 458). The accuracy was 99.42% (2 547/2 562). The result of Kappa consistency analysis showed that the two parts were the same (Kappa=0.926). Coefficient of variation (CV) of each HPV types was less than 5%.No pollution phenomenon was found. AUTRAX automatic nucleic acids extraction workstation can be used for the HPV subtypes detection in clinical settings.

  16. Effects of dynamic workstation Oxidesk on acceptance, physical activity, mental fitness and work performance

    NARCIS (Netherlands)

    Groenesteijn, L.; Commissaris, D.A.C.M.; Berg-Zwetsloot, M. van den; Hiemstra-Van Mastrigt, S.

    2016-01-01

    BACKGROUND: Working in an office environment is characterised by physical inactivity and sedentary behaviour. This behaviour contributes to several health risks in the long run. Dynamic workstations which allow people to combine desk activities with physical activity, may contribute to prevention of

  17. Flexible structure control experiments using a real-time workstation for computer-aided control engineering

    Science.gov (United States)

    Stieber, Michael E.

    1989-01-01

    A Real-Time Workstation for Computer-Aided Control Engineering has been developed jointly by the Communications Research Centre (CRC) and Ruhr-Universitaet Bochum (RUB), West Germany. The system is presently used for the development and experimental verification of control techniques for large space systems with significant structural flexibility. The Real-Time Workstation essentially is an implementation of RUB's extensive Computer-Aided Control Engineering package KEDDC on an INTEL micro-computer running under the RMS real-time operating system. The portable system supports system identification, analysis, control design and simulation, as well as the immediate implementation and test of control systems. The Real-Time Workstation is currently being used by CRC to study control/structure interaction on a ground-based structure called DAISY, whose design was inspired by a reflector antenna. DAISY emulates the dynamics of a large flexible spacecraft with the following characteristics: rigid body modes, many clustered vibration modes with low frequencies and extremely low damping. The Real-Time Workstation was found to be a very powerful tool for experimental studies, supporting control design and simulation, and conducting and evaluating tests withn one integrated environment.

  18. Micro machining workstation for a diode pumped Nd:YAG high brightness laser system

    NARCIS (Netherlands)

    Kleijhorst, R.A.; Offerhaus, Herman L.; Bant, P.

    1998-01-01

    A Nd:YAG micro-machining workstation that allows cutting on a scale of a few microns has been developed and operated. The system incorporates a telescope viewing system that allows control during the work and a software interface to translate AutoCad files. Some examples of the performance are

  19. Mammography workstation design: effect on mammographer behaviour and the risk of musculoskeletal disorders

    Science.gov (United States)

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

    2008-03-01

    In the UK Breast Screening Programme there is a growing transition from film to digital mammography, and consequently a change in mammography workstation ergonomics. This paper investigates the effect of the change for radiologists including their comfort, likelihood of developing musculoskeletal disorders (MSD's), and work practices. Three workstations types were investigated: one with all film mammograms; one with digital mammograms alongside film mammograms from the previous screening round, and one with digital mammograms alongside digitised film mammograms from the previous screening round. Mammographers were video-taped whilst conducting work sessions at each of the workstations. Event based Rapid Upper Limb Assessment (RULA) postural analysis showed no overall increase in MSD risk level in the switch from the film to digital workstation. Average number of visual glances at the prior mammograms per case measured by analysis of recorded video footage showed an increase if the prior mammograms were digitised, rather than displayed on a multi-viewer (p<.05). This finding has potential implications for mammographer performance in the transition to digital mammography in the UK.

  20. Evaluation plan for a cardiological multi-media workstation (I4C project)

    NARCIS (Netherlands)

    Hofstede, J.W. van der; Quak, A.B.; Ginneken, A.M. van; Macfarlane, P.W.; Watson, J.; Hendriks, P.R.; Zeelenberg, C.

    1997-01-01

    The goal of the I4C project (Integration and Communication for the Continuity of Cardiac Care) is to build a multi-media workstation for cardiac care and to assess its impact in the clinical setting. This paper describes the technical evaluation plan for the prototype.

  1. 76 FR 10403 - Hewlett Packard (HP), Global Product Development, Engineering Workstation Refresh Team, Working...

    Science.gov (United States)

    2011-02-24

    ... Workstation Refresh Team, Working On-Site at General Motors Corporation, Milford, MI; Notice of Revised... Engineering Application Support Team, working on-site at General Motors Corporation, Milford, Michigan... Team, working on-site at General Motors Corporation, Milford, Michigan, who became totally or partially...

  2. Feature extraction for EEG-based brain-computer interfaces by wavelet packet best basis decomposition.

    Science.gov (United States)

    Yang, Bang-hua; Yan, Guo-zheng; Yan, Rong-guo; Wu, Ting

    2006-12-01

    A method based on wavelet packet best basis decomposition (WPBBD) is investigated for the purpose of extracting features of electroencephalogram signals produced during motor imagery tasks in brain-computer interfaces. The method includes the following three steps. (1) Original signals are decomposed by wavelet packet transform (WPT) and a wavelet packet library can be formed. (2) The best basis for classification is selected from the library. (3) Subband energies included in the best basis are used as effective features. Three different motor imagery tasks are discriminated using the features. The WPBBD produces a 70.3% classification accuracy, which is 4.2% higher than that of the existing wavelet packet method.

  3. Feature extraction for EEG-based brain computer interfaces by wavelet packet best basis decomposition

    Science.gov (United States)

    Yang, Bang-hua; Yan, Guo-zheng; Yan, Rong-guo; Wu, Ting

    2006-12-01

    A method based on wavelet packet best basis decomposition (WPBBD) is investigated for the purpose of extracting features of electroencephalogram signals produced during motor imagery tasks in brain-computer interfaces. The method includes the following three steps. (1) Original signals are decomposed by wavelet packet transform (WPT) and a wavelet packet library can be formed. (2) The best basis for classification is selected from the library. (3) Subband energies included in the best basis are used as effective features. Three different motor imagery tasks are discriminated using the features. The WPBBD produces a 70.3% classification accuracy, which is 4.2% higher than that of the existing wavelet packet method.

  4. The application study of wavelet packet transformation in the de-noising of dynamic EEG data.

    Science.gov (United States)

    Li, Yifeng; Zhang, Lihui; Li, Baohui; Wei, Xiaoyang; Yan, Guiding; Geng, Xichen; Jin, Zhao; Xu, Yan; Wang, Haixia; Liu, Xiaoyan; Lin, Rong; Wang, Quan

    2015-01-01

    This paper briefly describes the basic principle of wavelet packet analysis, and on this basis introduces the general principle of wavelet packet transformation for signal den-noising. The dynamic EEG data under +Gz acceleration is made a de-noising treatment by using wavelet packet transformation, and the de-noising effects with different thresholds are made a comparison. The study verifies the validity and application value of wavelet packet threshold method for the de-noising of dynamic EEG data under +Gz acceleration.

  5. [Epileptic EEG signal classification based on wavelet packet transform and multivariate multiscale entropy].

    Science.gov (United States)

    Xu, Yonghong; Li, Xingxing; Zhao, Yong

    2013-10-01

    In this paper, a new method combining wavelet packet transform and multivariate multiscale entropy for the classification of epilepsy EEG signals is introduced. Firstly, the original EEG signals are decomposed at multi-scales with the wavelet packet transform, and the wavelet packet coefficients of the required frequency bands are extracted. Secondly, the wavelet packet coefficients are processed with multivariate multiscale entropy algorithm. Finally, the EEG data are classified by support vector machines (SVM). The experimental results on the international public Bonn epilepsy EEG dataset show that the proposed method can efficiently extract epileptic features and the accuracy of classification result is satisfactory.

  6. Maintenance Support for DARPA SATNET Packet Communications System

    Science.gov (United States)

    1980-09-30

    modifications and the frequencies of the 2 oscillators in the modems for these earth terminals have been set to the proper values, the modems for ETAM ...and thus abort the demodulation of the full packet. This problem has been corrected and the T&M words have been turned on at ETAM . It is now necessary...fairly accurately. Figure 1 shows that ETA and Goonhilly are roughly at the same power level and TANUM is about 2 dB lower. It is also noted that ETAM

  7. Packetizing OCP Transactions in the MANGO Network-on-Chip

    DEFF Research Database (Denmark)

    Bjerregaard, Tobias; Sparsø, Jens

    2006-01-01

    The scaling of CMOS technology causes a widening gap between the performance of on-chip communication and computation. This calls for a communication-centric design flow. The MANGO network-on-chip architecture enables globally asynchronous locally synchronous (GALS) system-on-chip design, while...... transactions are packetized and transmitted across the shared network, and illustrate how this affects the end-to-end performance. A high predictability of the latency of communication on shared links is shown in a MANGO-based demonstrator system...

  8. Techniques for the Detection of Faulty Packet Header Modifications

    Science.gov (United States)

    2014-03-12

    Since then, a variety of solutions employing these principles have been devel- oped [3, 37–40]. xOMB (pronounced “ zombie ”) [37] is a modular software...limited TCP probes and examining ICMP quotations from the ICMP TTL-exceeded mes- sages that come back when the packet expires. The RFC that defines the...However, with no out-of-band channel between the two end hosts and no Diffie-Hellman- like setup, coming up with such a shared secret is difficult

  9. A Time-Frequency Auditory Model Using Wavelet Packets

    DEFF Research Database (Denmark)

    Agerkvist, Finn

    1996-01-01

    A time-frequency auditory model is presented. The model uses the wavelet packet analysis as the preprocessor. The auditory filters are modelled by the rounded exponential filters, and the excitation is smoothed by a window function. By comparing time-frequency excitation patterns it is shown...... that the change in the time-frequency excitation pattern introduced when a test tone at masked threshold is added to the masker is approximately equal to 7 dB for all types of maskers. The classic detection ratio therefore overrates the detection efficiency of the auditory system....

  10. Effects of wireless packet loss in industrial process control systems.

    Science.gov (United States)

    Liu, Yongkang; Candell, Richard; Moayeri, Nader

    2017-05-01

    Timely and reliable sensing and actuation control are essential in networked control. This depends on not only the precision/quality of the sensors and actuators used but also on how well the communications links between the field instruments and the controller have been designed. Wireless networking offers simple deployment, reconfigurability, scalability, and reduced operational expenditure, and is easier to upgrade than wired solutions. However, the adoption of wireless networking has been slow in industrial process control due to the stochastic and less than 100% reliable nature of wireless communications and lack of a model to evaluate the effects of such communications imperfections on the overall control performance. In this paper, we study how control performance is affected by wireless link quality, which in turn is adversely affected by severe propagation loss in harsh industrial environments, co-channel interference, and unintended interference from other devices. We select the Tennessee Eastman Challenge Model (TE) for our study. A decentralized process control system, first proposed by N. Ricker, is adopted that employs 41 sensors and 12 actuators to manage the production process in the TE plant. We consider the scenario where wireless links are used to periodically transmit essential sensor measurement data, such as pressure, temperature and chemical composition to the controller as well as control commands to manipulate the actuators according to predetermined setpoints. We consider two models for packet loss in the wireless links, namely, an independent and identically distributed (IID) packet loss model and the two-state Gilbert-Elliot (GE) channel model. While the former is a random loss model, the latter can model bursty losses. With each channel model, the performance of the simulated decentralized controller using wireless links is compared with the one using wired links providing instant and 100% reliable communications. The sensitivity of the

  11. On the Packet Loss Correlation in Wireless Mesh Networks

    DEFF Research Database (Denmark)

    Pahlevani, Peyman; Cabrera Guerrero, Juan Alberto; Roetter, Daniel Enrique Lucani

    2014-01-01

    /or multi-path routing approaches as well as network coding (NC) subgraph selection problems (routing in NC). This paper proposes simple channel models to incorporate the effect of correlation between receivers in a parametric fashion and supports them with a measurement campaign that leverages various......State-of-the-art analysis and protocols in wireless mesh networks typically assume an independent packet loss channel for each receiver of a transmission. Although this is usually transparent for single-path protocol design, this assumption may severely degrade the performance of opportunistic and...

  12. Electroencephalography data analysis by using discrete wavelet packet transform

    Science.gov (United States)

    Karim, Samsul Ariffin Abdul; Ismail, Mohd Tahir; Hasan, Mohammad Khatim; Sulaiman, Jumat; Muthuvalu, Mohana Sundaram; Janier Josefina, B.

    2015-05-01

    Electroencephalography (EEG) is the electrical activity generated by the movement of neurons in the brain. It is categorized into delta waves, theta, alpha, beta and gamma. These waves exist in a different frequency band. This paper is a continuation of our previous research. EEG data will be decomposed using Discrete Wavelet Packet Transform (DWPT). Daubechies wavelets 10 (D10) will be used as the basic functions for research purposes. From the main results, it is clear that the DWPT able to characterize the EEG signal corresponding to each wave at a specific frequency. Furthermore, the numerical results obtained better than the results using DWT. Statistical analysis support our main findings.

  13. Performance Characteristics of a Kernel-Space Packet Capture Module

    Science.gov (United States)

    2010-03-01

    PF_RING protocol prevents the packets from going through the net- work stack, allowing the NIC driver to deliver the skb directly to a ring-buffer that is...protocol tap, if any are run- ning - Passing a copy of the frame to the L3 protocol handler associated with skb ->protocol - Taking care of those features...1468,5 +1502,14 @@ skb −>cloned ) ; #endif + + +# i f d e f PKAP_ENABLED + atomic_dec(&pfr−>num_ring_users ) ; +#e lse / * PKAP * / atomic_set(&pfr

  14. Observation of Accelerating Wave Packets in Curved Space

    Directory of Open Access Journals (Sweden)

    Anatoly Patsyk

    2018-01-01

    Full Text Available We present the first experimental observation of accelerating beams in curved space. More specifically, we demonstrate, experimentally and theoretically, shape-preserving accelerating beams propagating on spherical surfaces: closed-form solutions of the wave equation manifesting nongeodesic self-similar evolution. Unlike accelerating beams in flat space, these wave packets change their acceleration trajectory due to the interplay between interference effects and the space curvature, and they focus and defocus periodically due to the spatial curvature of the medium in which they propagate.

  15. The driver workstation in commercial vehicles; Ergonomie und Design von Fahrerarbeitsplaetzen in Nutzfahrzeugen

    Energy Technology Data Exchange (ETDEWEB)

    Kraus, W. [HAW-Hamburg (Germany)

    2003-07-01

    Nowadays, ergonomics and design are quality factors and indispensable elements of commercial vehicle design and development. Whereas a vehicle's appearance, i.e. its outside design, produces fascination and image, the design of its passenger cell focuses entirely on drivers and their tasks. Today, passenger-cell design and the ergonomics of driver workstations in commercial vehicles are clearly becoming more and more important. This article concentrates above all on defining commercial vehicle drivers, which, within the scope of research projects on coach-driver workstations, has provided new insight into the design of driver workstations. In light of the deficits determined, the research project mainly focused on designing driver workstations which were in line with the latest findings in ergonomics and human engineering. References to the methodology of driver-workstation optimization seems important in this context. The afore-mentioned innovations in the passenger cells of commercial vehicles will be explained and described by means of topical and practical examples. (orig.) [German] Ergonomie und Design sind heute Qualitaetsfaktoren und unverzichtbarer Bestandteil bei der Entwicklung von Nutzfahrzeugen. Erzeugt das Erscheinungsbild, die Aussengestaltung des Fahrzeugs, die Faszination und das Image, so ist die Innengestaltung weitgehend ganz auf die Bedienpersonen und ihre Arbeitsaufgaben bezogen. Die Innenraumgestaltung und die Ergonomie von Fahrerarbeitsplaetzen in Nutzfahrzeugen sind heute in einer Phase der deutlichen Aufwertung zu sehen. Im Beitrag wird besonders auf die Definition der Bedienpersonen fuer Nutzfahrzeuge eingegangen, die im Rahmen des Forschungsprojekts Fahrerarbeitsplatz im Reisebus zu neuen Erkenntnissen bei der Auslegung von Arbeitsplaetzen fuehrte. Gemaess der ermittelten Defizite konzentriert sich die Studie im Kern auf das Gestaltungskonzept des Fahrerarbeitsplatzes nach ergonomischen und arbeitswissenschaftlichen Erkenntnissen

  16. Rolling bearing fault diagnosis using adaptive deep belief network with dual-tree complex wavelet packet.

    Science.gov (United States)

    Shao, Haidong; Jiang, Hongkai; Wang, Fuan; Wang, Yanan

    2017-07-01

    Automatic and accurate identification of rolling bearing fault categories, especially for the fault severities and compound faults, is a challenge in rotating machinery fault diagnosis. For this purpose, a novel method called adaptive deep belief network (DBN) with dual-tree complex wavelet packet (DTCWPT) is developed in this paper. DTCWPT is used to preprocess the vibration signals to refine the fault characteristics information, and an original feature set is designed from each frequency-band signal of DTCWPT. An adaptive DBN is constructed to improve the convergence rate and identification accuracy with multiple stacked adaptive restricted Boltzmann machines (RBMs). The proposed method is applied to the fault diagnosis of rolling bearings. The results confirm that the proposed method is more effective than the existing methods. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  17. Bearing fault detection using motor current signal analysis based on wavelet packet decomposition and Hilbert envelope

    Directory of Open Access Journals (Sweden)

    Imaouchen Yacine

    2015-01-01

    Full Text Available To detect rolling element bearing defects, many researches have been focused on Motor Current Signal Analysis (MCSA using spectral analysis and wavelet transform. This paper presents a new approach for rolling element bearings diagnosis without slip estimation, based on the wavelet packet decomposition (WPD and the Hilbert transform. Specifically, the Hilbert transform first extracts the envelope of the motor current signal, which contains bearings fault-related frequency information. Subsequently, the envelope signal is adaptively decomposed into a number of frequency bands by the WPD algorithm. Two criteria based on the energy and correlation analyses have been investigated to automate the frequency band selection. Experimental studies have confirmed that the proposed approach is effective in diagnosing rolling element bearing faults for improved induction motor condition monitoring and damage assessment.

  18. Mapping of Coherent Nuclear Wave Packet Dynamics in D_2^+ with Ultrashort Laser Pulses

    Science.gov (United States)

    Feuerstein, Bernold; Thumm, Uwe

    2003-05-01

    Fast ionization of D2 leads to the coherent population of many vibrational states of D_2^+. Usually, only the squared absolute values of the vibrational state amplitudes, known as Franck-Condon factors, are observed since insufficient experimental time resolution averages out all coherence effects. We propose a Coulomb explosion imaging method to visualize the coherent motion of bound wave packets using ultrashort (5 fs), intense pump-probe laser pulses. With this type of experiment, decoherence times in the fs to ps range could be directly measured, providing essential information for coherent control. Supported in part by NSF (grant PHY-0071035) and Division of Chemical Sciences, Office of Basic Energy Scienes, Office of Energy Research, US DOE.

  19. A Workshop on UNIX, Workstations, and Internet Connections.

    Science.gov (United States)

    Vierheller, Timothy R.

    1997-01-01

    Describes a workshop that introduces participants to the UNIX operating system. Provides an overview of how to access information on the Internet and gain familiarity with Web browsers, file transfer programs, telnet sessions, newsreaders, and Gopher services. (DDR)

  20. Packet loss rate prediction using the sparse basis prediction model.

    Science.gov (United States)

    Atiya, Amir E; Yoo, Sung Goo; Chong, Kil To; Kim, Hyongsuk

    2007-05-01

    The quality of multimedia communicated through the Internet is highly sensitive to packet loss. In this letter, we develop a time-series prediction model for the end-to-end packet loss rate (PLR). The estimate of the PLR is needed in several transmission control mechanisms such as the TCP-friendly congestion control mechanism for UDP traffic. In addition, it is needed to estimate the amount of redundancy for the forward error correction (FEC) mechanism. An accurate prediction would therefore be very valuable. We used a relatively novel prediction model called sparse basis prediction model. It is an adaptive nonlinear prediction approach, whereby a very large dictionary of possible inputs are extracted from the time series (for example, through moving averages, some nonlinear transformations, etc.). Only few of the very best inputs among the dictionary are selected and are combined linearly. An algorithm adaptively updates the input selection (as well as updates the weights) each time a new time sample arrives in a computationally efficient way. Simulation experiments indicate significantly better prediction performance for the sparse basis approach, as compared to other traditional nonlinear approaches.

  1. Qualitative dynamics of wave packets in turbulent jets

    Science.gov (United States)

    Semeraro, Onofrio; Lusseyran, François; Pastur, Luc; Jordan, Peter

    2017-09-01

    We analyze the temporal dynamics associated with axisymmetric coherent structures in a turbulent jet. It has long been established that turbulent jets comprise large-scale coherent structures, now more commonly referred to as "wave packets" [Jordan and Colonius, Annu. Rev. Fluid Mech. 45, 173 (2013), 10.1146/annurev-fluid-011212-140756]. These structures exhibit a marked spatiotemporal organization, despite turbulence, and we aim to characterize their temporal dynamics by means of nonlinear statistical tools. The analysis is based on data presented Breakey et al., in Proceedings of the 19th AIAA/CEAS Aeroacoustics Conference, AIAA Paper 2013-2083 (AIAA, Reston, VA, 2013), where time series of the wave-packet signatures are extracted at different streamwise locations. The experiment runs at Ma=0.6 and Re=5.7 ×105 . A thorough analysis is performed. Statistical tools are used to estimate the embedding and correlation dimensions that characterize the dynamical system. Input-output transfer functions are designed as control-oriented models; and for this special case, consistent with other recent studies, we find that linear models can reproduce much of the convective input-ouput behavior. Finally, we show how surrogate models can partially reproduce the nonlinear dynamics.

  2. Parametric packet-based audiovisual quality model for IPTV services

    CERN Document Server

    Garcia, Marie-Neige

    2014-01-01

    This volume presents a parametric packet-based audiovisual quality model for Internet Protocol TeleVision (IPTV) services. The model is composed of three quality modules for the respective audio, video and audiovisual components. The audio and video quality modules take as input a parametric description of the audiovisual processing path, and deliver an estimate of the audio and video quality. These outputs are sent to the audiovisual quality module which provides an estimate of the audiovisual quality. Estimates of perceived quality are typically used both in the network planning phase and as part of the quality monitoring. The same audio quality model is used for both these phases, while two variants of the video quality model have been developed for addressing the two application scenarios. The addressed packetization scheme is MPEG2 Transport Stream over Real-time Transport Protocol over Internet Protocol. In the case of quality monitoring, that is the case for which the network is already set-up, the aud...

  3. Two-law approximation for voice delay in packet networks

    Science.gov (United States)

    Pazhyannur, Rajesh S.; Fleming, Philip J.

    2001-07-01

    Traditionally, voice has been transported using circuit switched networks, the Public Switched Telephone Network (PSTN) for example. However, driven by the ubiquity of the Internet and the development of low bit-rate digital voice codecs there has been increasing focus on using packet-switched networks for voice traffic. We focus on one such application. Our model comprises of a relatively slow packet link (between 1.5 and 5.0 Mbps) being utilized for voice traffic. Large number (of the order of 100) voice sources are multiplexed on this link. For such a link we obtain delay distributions seen by a voice source. Specifically, we exploit key characteristics of the model, such as the large number of sources to obtain a heavy traffic approximation for the system. The key result is that the delays can be well approximated by concatenation of two exponential distributions. We also provide valuable insight into how the delay distribution is connected with the statistical properties of the voice sources, in particular their correlation behavior. Our analytical results are validated with simulation results.

  4. Design of a workstation and its evaluation under the influence of noise and illumination for an assembly task.

    Science.gov (United States)

    Muzammil, Mohammad; Ahmad, Saman; Khan, Abid Ali; Hasan, Faisal

    2011-01-01

    An experimental research was conducted to design a workstation for a lock manufacturing assembly. Two experiments were conducted in the present study. Nine male subjects in the age range of 18-35 years participated in the first experiment. For the second experiment, nine subjects in each of the three age groups (viz. 17-22, 23-28 and 29-35 years) volunteered for experimental investigations. The designed workstation was evaluated under varying levels of noise and illumination for workers of different age groups. Three different workstations were evaluated. The task was performed by a worker in two different sitting positions and three settings of arms position. It was found that workstation type, backrest support and arms positions were all having a statistically significant effect on task performance. Workstation with work surface to seat height ratio of 1.82 was found to be better when the task was performed using backrest and arms were supported on the work surface. This workstation was evaluated for three different age groups of workers under different levels of noise and illumination. The results of the study showed that age of the worker, illumination level and level of noise were all contributing significantly towards task performance. The design of a workstation for assembly task would help greatly in creating a better working environment and enhancing the productivity of workers exposed to environmental stressors like noise and illumination. © 2011 - IOS Press and the authors. All rights reserved

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

    Science.gov (United States)

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

    2017-08-01

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

  6. Comparison of full-field digital mammography workstation and conventional picture archiving and communication system in image quality and diagnostic performance.

    Science.gov (United States)

    Kang, Bong Joo; Kim, Sung Hun; Choi, Byung Gil

    2011-01-01

    The object of this study was to compare of full-field digital mammography (FFDM) workstation and conventional picture archiving and communication systems (PACS) in image quality and diagnostic performance. We assembled 80 masses and 80 microcalcifications. Images were displayed on workstation, 5M, and 3M PACS monitors. The image quality for mammograms on workstation was significantly better than that for mammograms on PACS monitors. The sensitivity and NPV for microcalcifications on workstation were higher than those on PACS monitors. The conventional PACS cannot substitute for a FFDM workstation for mammographic evaluation. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. 4x4 optical packet switching of asynchronous burst optical packets with a prototype, 4x4 label processing and switching sub-system.

    Science.gov (United States)

    Urata, Ryohei; Nakahara, Tatsushi; Takenouchi, Hirokazu; Segawa, Toru; Ishikawa, Hiroshi; Ohki, Akira; Sugiyama, Hiroki; Nishihara, Susumu; Takahashi, Ryo

    2010-07-19

    We report a prototype, 4x4 (4 input/4 output) label processing and switching sub-system for 10-Gb/s asynchronous burst variable-length optical packets. With the prototype, we perform a 4x4 optical packet switching demonstration, achieving error-free (BERswitching operation for all possible input/output combinations (16 switching paths) simultaneously. Power consumption and latency of the entire, self-contained sub-system is 83 W (includes fan power) and 300 ns, respectively.

  8. Packetized Predictive Control for Rate-Limited Networks via Sparse Representation

    DEFF Research Database (Denmark)

    Nagahara, Masaaki; Quevedo, Daniel; Østergaard, Jan

    2012-01-01

    controller and the plant input. To achieve robustness with respect to dropouts, the controller transmits data packets containing plant input predictions, which minimize a finite horizon cost function. In our formulation, we design sparse packets for rate-limited networks, by adopting an an ℓ0 optimization...

  9. Guide to Alternative Mortgage Instruments. Teachers Instructional Packet, TIP No. 4, Spring 1985.

    Science.gov (United States)

    Texas A and M Univ., College Station. Texas Real Estate Research Center.

    Part of a series of classroom aids designed for real estate instructors, this instructional packet was developed to help real estate students understand the various alternative mortgage instruments, including their major advantages and disadvantages. First, an evaluation form for the packet is presented. Next, a summary presentation on four basic…

  10. 106-17 Telemetry Standards Recorder Data Packet Format Standard Chapter 11

    Science.gov (United States)

    2017-07-01

    Video Frame Format, 16-Bit Little-Endian Aligned...11-66 Figure 11-49. Format 0 MPEG-2/H.264 Video Frame Format, 16-Bit Big-Endian (Native) Aligned...Figure 11-60. Image Data Intra-Packet Header, Format 0 ............................................... 11-81 Figure 11-61. Still Imagery Packet Channel

  11. Flow monitoring explained: from packet capture to data analysis with NetFlow and IPFIX

    NARCIS (Netherlands)

    Hofstede, R.J.; Celeda, Pavel; Trammell, Brian; Drago, Idilio; Sadre, R.; Sperotto, Anna; Pras, Aiko

    2014-01-01

    Flow monitoring has become a prevalent method for monitoring traffic in high-speed networks. By focusing on the analysis of flows, rather than individual packets, it is often said to be more scalable than traditional packet-based traffic analysis. Flow monitoring embraces the complete chain of

  12. Joint Connection and Packet level Analysis in W-CDMA Radio Interface

    DEFF Research Database (Denmark)

    Benetis, Vilius; Popova, Larissa; Iversen, Villy Bæk

    2007-01-01

    This work introduces a new analytical method for performance evaluation of wireless packet-oriented networks. Unlike traditional call admission control procedures commonly used for performance evaluation of wireless networks, this paper deals with the problem of coupling connection and packet lev...

  13. Remark on characterization of wave front set by wave packet transform

    OpenAIRE

    Kato, Keiichi; Kobayashi, Masaharu; Ito, Shingo

    2017-01-01

    In this paper, we give characterizations of usual wave front set and wave front set in $H^s$ in terms of wave packet transform without any restriction on basic wave packet, which give complete answers of the question raised by G. B. Folland.

  14. A Scheduling Algorithm for Time Bounded Delivery of Packets on the Internet

    NARCIS (Netherlands)

    I. Vaishnavi (Ishan)

    2008-01-01

    htmlabstractThis thesis aims to provide a better scheduling algorithm for Real-Time delivery of packets. A number of emerging applications such as VoIP, Tele-immersive environments, distributed media viewing and distributed gaming require real-time delivery of packets. Currently the scheduling

  15. Fair & power-efficient channel-dependent scheduling for CDMA packet networks

    NARCIS (Netherlands)

    Zan, Lei; Heijenk, Geert; El Zarki, Magda

    2003-01-01

    Recently, there has been a significant increase in the amount of packet data services, such as web browsing, being offered over mobile phones. Data services are expected to account for the highest volume of traffic soon. However, current downlink scheduling algorithms for packet data services cannot

  16. Simulation on the electronic wave packet cyclotron motion in a Weyl semimetal slab.

    Science.gov (United States)

    Yao, Haibo; Zhu, Mingfeng; Jiang, Liwei; Zheng, Yisong

    2017-04-20

    We perform a numerical simulation on the time evolution of an electronic wave packet in a Weyl semimetal (WSM) slab driven by a magnetic field. We find that the evolution trajectory of the wave packet depends sensitively on its initial spin state. Only with initial spin state identical to that of the Fermi arc state at the surface it localized, does the wave packet evolution demonstrate the characteristic cyclotron orbit of WSM previously predicted from a semiclassical viewpoint. By analyzing the eigen-expansion of the electronic wave packet, we find the chiral Landau levels (LLs) of the WSM slab, as ingredients of the wave packet, to be responsible for establishing the characteristic WSM cyclotron orbit. In contrast, the nonchiral LLs contribute irregular oscillations to the wave packet evolution, going against the formation of a well-defined cyclotron orbit. In addition, the tilted magnetic field does not affect the motion of the electronic wave packet along the Fermi arcs in the momentum space. It does, however, alter the evolution trajectory of the electronic wave packet in real space and spin space. Finally, the energy disalignment of the Weyl nodes results in a 3D cyclotron orbit in real space.

  17. Protection of Video Packets over a Wireless Rayleigh Fading Link: FEC versus ARQ

    Directory of Open Access Journals (Sweden)

    Marc Moeneclaey

    2008-07-01

    Full Text Available Video content can be provided to an end user by transmitting video data as a sequence of internet protocol (IP packets over the network. When the network contains a wireless link, packet erasures occur because of occasional deep fades. In order to maintain a sufficient video quality at the end user, video packets must be protected against erasures by means of a suitable form of error control. In this contribution, we investigate two types of error control: (1 forward error correction (FEC, which involves the transmission of parity packets that enables recovery of a limited number of erased video packets, and (2 the use of an automatic repeat request (ARQ protocol, where the receiver requests the retransmission of video packets that have been erased. We point out that FEC and ARQ considerably reduce the probability of unrecoverable packet loss, because both error control techniques provide a diversity gain, as compared to the case where no protection against erasures is applied. We derive a simple analytical expression for the diversity gain resulting from FEC or ARQ, in terms of the channel coherence time, the allowable latency, and (for FEC the allowable overhead or (for ARQ the time interval between (retransmissions of copies of a same packet. In the case of HDTV transmission over a 60 GHz indoor wireless link, ARQ happens to outperform FEC.

  18. On the fractional Fourier and continuous fractional wave packet transforms of almost periodic functions

    Directory of Open Access Journals (Sweden)

    Banu Ünalmış Uzun

    2017-06-01

    Full Text Available Abstract We state the fractional Fourier transform and the continuous fractional wave packet transform as ways for analyzing persistent signals such as almost periodic functions and strong limit power signals. We construct frame decompositions for almost periodic functions using these two transforms. Also a norm equality of this signal is given using the continuous fractional wave packet transform.

  19. On the fractional Fourier and continuous fractional wave packet transforms of almost periodic functions.

    Science.gov (United States)

    Uzun, Banu Ünalmış

    2017-01-01

    We state the fractional Fourier transform and the continuous fractional wave packet transform as ways for analyzing persistent signals such as almost periodic functions and strong limit power signals. We construct frame decompositions for almost periodic functions using these two transforms. Also a norm equality of this signal is given using the continuous fractional wave packet transform.

  20. On the fractional Fourier and continuous fractional wave packet transforms of almost periodic functions

    OpenAIRE

    Uzun, Banu ?nalm??

    2017-01-01

    We state the fractional Fourier transform and the continuous fractional wave packet transform as ways for analyzing persistent signals such as almost periodic functions and strong limit power signals. We construct frame decompositions for almost periodic functions using these two transforms. Also a norm equality of this signal is given using the continuous fractional wave packet transform.

  1. On the fractional Fourier and continuous fractional wave packet transforms of almost periodic functions

    OpenAIRE

    Banu Ünalmış Uzun

    2017-01-01

    Abstract We state the fractional Fourier transform and the continuous fractional wave packet transform as ways for analyzing persistent signals such as almost periodic functions and strong limit power signals. We construct frame decompositions for almost periodic functions using these two transforms. Also a norm equality of this signal is given using the continuous fractional wave packet transform.

  2. 160 Gb/s all-optical packet switching field experiment

    DEFF Research Database (Denmark)

    Dorren, H.J.S.; Herrera, J.; Raz, O.

    2007-01-01

    We discus an all-optical packet switching experiment over 110 km of field installed optical fiber. The switching node is controlled by solely photonic control circuits.......We discus an all-optical packet switching experiment over 110 km of field installed optical fiber. The switching node is controlled by solely photonic control circuits....

  3. Dynamic optical fiber delivery of Ka-band packet transmissions for wireless access networks

    DEFF Research Database (Denmark)

    Rodríguez Páez, Juan Sebastián; Madsen, Peter; Tafur Monroy, Idelfonso

    2017-01-01

    A Reconfigurable Radio Access Unit is presented and experimentally demonstrated. In the unit, an optical switching system is set to dynamically deliver different packets to different points in the network. The packets are transmitted wirelesslty on the Ka-band (26–40 GHz), achieving BER values...

  4. An analytical model for perpetual network codes in packet erasure channels

    DEFF Research Database (Denmark)

    Pahlevani, Peyman; Crisostomo, Sergio; Roetter, Daniel Enrique Lucani

    2016-01-01

    Perpetual codes provide a sparse, but structured coding for fast encoding and decoding. In this work, we illustrate that perpetual codes introduce linear dependent packet transmissions in the presence of an erasure channel. We demonstrate that the number of linear dependent packet transmissions i...

  5. MIDAS-W: a workstation-based incoherent scatter radar data acquisition system

    Directory of Open Access Journals (Sweden)

    J. M. Holt

    Full Text Available The Millstone Hill Incoherent Scatter Data Acquisition System (MIDAS is based on an abstract model of an incoherent scatter radar. This model is implemented in a hierarchical software system, which serves to isolate hardware and low-level software implementation details from higher levels of the system. Inherent in this is the idea that implementation details can easily be changed in response to technological advances. MIDAS is an evolutionary system, and the MIDAS hardware has, in fact, evolved while the basic software model has remained unchanged. From the earliest days of MIDAS, it was realized that some functions implemented in specialized hardware might eventually be implemented by software in a general-purpose computer. MIDAS-W is the realization of this concept. The core component of MIDAS-W is a Sun Microsystems UltraSparc 10 workstation equipped with an Ultrarad 1280 PCI bus analog to digital (A/D converter board. In the current implementation, a 2.25 MHz intermediate frequency (IF is bandpass sampled at 1 µs intervals and these samples are multicast over a high-speed Ethernet which serves as a raw data bus. A second workstation receives the samples, converts them to filtered, decimated, complex baseband samples and computes the lag-profile matrix of the decimated samples. Overall performance is approximately ten times better than the previous MIDAS system, which utilizes a custom digital filtering module and array processor based correlator. A major advantage of MIDAS-W is its flexibility. A portable, single-workstation data acquisition system can be implemented by moving the software receiver and correlator programs to the workstation with the A/D converter. When the data samples are multicast, additional data processing systems, for example for raw data recording, can be implemented simply by adding another workstation with suitable software to the high-speed network. Testing of new data processing software is also greatly

  6. MIDAS-W: a workstation-based incoherent scatter radar data acquisition system

    Directory of Open Access Journals (Sweden)

    J. M. Holt

    2000-09-01

    Full Text Available The Millstone Hill Incoherent Scatter Data Acquisition System (MIDAS is based on an abstract model of an incoherent scatter radar. This model is implemented in a hierarchical software system, which serves to isolate hardware and low-level software implementation details from higher levels of the system. Inherent in this is the idea that implementation details can easily be changed in response to technological advances. MIDAS is an evolutionary system, and the MIDAS hardware has, in fact, evolved while the basic software model has remained unchanged. From the earliest days of MIDAS, it was realized that some functions implemented in specialized hardware might eventually be implemented by software in a general-purpose computer. MIDAS-W is the realization of this concept. The core component of MIDAS-W is a Sun Microsystems UltraSparc 10 workstation equipped with an Ultrarad 1280 PCI bus analog to digital (A/D converter board. In the current implementation, a 2.25 MHz intermediate frequency (IF is bandpass sampled at 1 µs intervals and these samples are multicast over a high-speed Ethernet which serves as a raw data bus. A second workstation receives the samples, converts them to filtered, decimated, complex baseband samples and computes the lag-profile matrix of the decimated samples. Overall performance is approximately ten times better than the previous MIDAS system, which utilizes a custom digital filtering module and array processor based correlator. A major advantage of MIDAS-W is its flexibility. A portable, single-workstation data acquisition system can be implemented by moving the software receiver and correlator programs to the workstation with the A/D converter. When the data samples are multicast, additional data processing systems, for example for raw data recording, can be implemented simply by adding another workstation with suitable software to the high-speed network. Testing of new data processing software is also greatly

  7. A Neural Network Based Workstation for Automated Cell Proliferation Analysis

    Science.gov (United States)

    2001-10-25

    proliferation analysis, of cytological microscope images. The software of the system assists the expert biotechnologist during cell proliferation and...work was supported by the Programa de Apoyo a Proyectos de Desarrollo e Investigacíon en Informática REDII 2000. We thank Blanca Itzel Taboada for

  8. New scheme of variable optical buffer for IP packets used in access control of HORNET

    Science.gov (United States)

    Fang, Nian; Wang, Lutang; Huang, Zhaoming

    2002-09-01

    A new scheme of variable optical buffer for IP packets is reported. It may be used in access control of HORNET (Hybrid Optoelectronic Ring NETwork), to avoid collision of added packet and the packet already on the ring and improve the loss ratio of the packets. In this scheme, a new multi-wavelength fiber loop memory technique is employed. This architecture uses the wavelength converter (WC) to specify the packets delay and wavelength conversion is accomplished by the technique of four-wave-mixing (FWM) with a semiconductor optical amplifier (SOA). The range of delay is 10 to 9990 bytes periods. First, architecture, operation principle, characteristics and applications of this scheme of variable optical buffer are introduced. Next, a new unslotted CSMA/CA MAC scheme based on the variable optical buffer is briefly introduced too. Finally, the simulation results are presented.

  9. E-model MOS Estimate Improvement through Jitter Buffer Packet Loss Modelling

    Directory of Open Access Journals (Sweden)

    Adrian Kovac

    2011-01-01

    Full Text Available Proposed article analyses dependence of MOS as a voice call quality (QoS measure estimated through ITU-T E-model under real network conditions with jitter. In this paper, a method of jitter effect is proposed. Jitter as voice packet time uncertainty appears as increased packet loss caused by jitter memory buffer under- or overflow. Jitter buffer behaviour at receiver’s side is modelled as Pareto/D/1/K system with Pareto-distributed packet interarrival times and its performance is experimentally evaluated by using statistic tools. Jitter buffer stochastic model is then incorporated into E-model in an additive manner accounting for network jitter effects via excess packet loss complementing measured network packet loss. Proposed modification of E-model input parameter adds two degrees of freedom in modelling: network jitter and jitter buffer size.

  10. Statistical Mechanics-Inspired Modeling of Heterogeneous Packet Transmission in Communication Networks.

    Science.gov (United States)

    Sarkar, S; Mukherjee, K; Ray, A; Srivastav, A; Wettergren, T A

    2012-08-01

    This paper presents the qualitative nature of communication network operations as abstraction of typical thermodynamic parameters (e.g., order parameter, temperature, and pressure). Specifically, statistical mechanics-inspired models of critical phenomena (e.g., phase transitions and size scaling) for heterogeneous packet transmission are developed in terms of multiple intensive parameters, namely, the external packet load on the network system and the packet transmission probabilities of heterogeneous packet types. Network phase diagrams are constructed based on these traffic parameters, and decision and control strategies are formulated for heterogeneous packet transmission in the network system. In this context, decision functions and control objectives are derived in closed forms, and the pertinent results of test and validation on a simulated network system are presented.

  11. Source Authentication for Code Dissemination Supporting Dynamic Packet Size in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Daehee Kim

    2016-07-01

    Full Text Available Code dissemination in wireless sensor networks (WSNs is a procedure for distributing a new code image over the air in order to update programs. Due to the fact that WSNs are mostly deployed in unattended and hostile environments, secure code dissemination ensuring authenticity and integrity is essential. Recent works on dynamic packet size control in WSNs allow enhancing the energy efficiency of code dissemination by dynamically changing the packet size on the basis of link quality. However, the authentication tokens attached by the base station become useless in the next hop where the packet size can vary according to the link quality of the next hop. In this paper, we propose three source authentication schemes for code dissemination supporting dynamic packet size. Compared to traditional source authentication schemes such as μTESLA and digital signatures, our schemes provide secure source authentication under the environment, where the packet size changes in each hop, with smaller energy consumption.

  12. Mapping of coherent and decohering nuclear wave-packet dynamics in D+2 with ultrashort laser pulses

    Science.gov (United States)

    Feuerstein, Bernold; Thumm, Uwe

    2003-06-01

    Fast ionization of D2 leads to the coherent population of many vibrational states of D+2. Usually, only the squared absolute values of the vibrational state amplitudes, known as Franck-Condon factors, are observed since insufficient experimental time resolution averages out all coherence effects. We propose a Coulomb explosion imaging method to visualize the coherent motion of bound wave packets using ultrashort (5 fs), intense pump-probe laser pulses. With this type of experiment decoherence times in the fs to ps range may become directly observable and provide essential information for coherent control.

  13. Optical label swapping and packet transmission based on ASK/DPSK orthogonal modulation format in IP-over-WDM networks

    DEFF Research Database (Denmark)

    Chi, Nan; Xu, Lin; Christiansen, Lotte Jin

    2003-01-01

    We demonstrate all-optical label swapping based on SOA, EAM and HNLF for a two-level optically labeled packet using orthogonal ASK/DPSK modulation format. The ASK/DPSK packet is successfully transmitted over 80 km NZDSF.......We demonstrate all-optical label swapping based on SOA, EAM and HNLF for a two-level optically labeled packet using orthogonal ASK/DPSK modulation format. The ASK/DPSK packet is successfully transmitted over 80 km NZDSF....

  14. Application of a screening method in assessing occupational safety and health of computer workstations.

    Science.gov (United States)

    Niskanen, Toivo; Lehtelä, Jouni; Länsikallio, Riina

    2014-01-01

    Employers and workers need concrete guidance to plan and implement changes in the ergonomics of computer workstations. The Näppärä method is a screening tool for identifying problems requiring further assessment and corrective actions. The aim of this study was to assess the work of occupational safety and health (OSH) government inspectors who used Näppärä as part of their OSH enforcement inspections (430 assessments) related to computer work. The modifications in workstation ergonomics involved mainly adjustments to the screen, mouse, keyboard, forearm supports, and chair. One output of the assessment is an index indicating the percentage of compliance items. This method can be considered as exposure assessment and ergonomics intervention used as a benchmark for the level of ergonomics. Future research can examine whether the effectiveness of participatory ergonomics interventions should be investigated with Näppärä.

  15. Development and Evaluation of the Habitat Demonstration Unit Medical Operations Workstation and Opportunities for Future Research

    Science.gov (United States)

    Howard, Robert L., Jr.

    2012-01-01

    As NASA develops missions to leave Earth orbit and explore distant destinations (Mars, Moon, Asteroids) it is necessary to rethink human spaceflight paradigms in the life sciences. Standards developed for low earth orbit human spaceflight may not be fully applicable and in-space research may be required to develop new standards. Preventative and emergency medical care may require new capabilities never before used in space. Due to spacecraft volume limitations, this work area may also be shared with various animal and plant life science research. This paper explores the prototype Medical Operations Workstation within the NASA Habitat Demonstration Unit and discusses some of the lessons learned from field analogue missions involving the workstation. Keywords: Exploration, medical, health, crew, injury emergency, biology, animal, plant, science, preventative, emergency.

  16. Computer modeling and design of diagnostic workstations and radiology reading rooms

    Science.gov (United States)

    Ratib, Osman M.; Amato, Carlos L.; Balbona, Joseph A.; Boots, Kevin; Valentino, Daniel J.

    2000-05-01

    We used 3D modeling techniques to design and evaluate the ergonomics of diagnostic workstation and radiology reading room in the planning phase of building a new hospital at UCLA. Given serious space limitations, the challenge was to provide more optimal working environment for radiologists in a crowded and busy environment. A particular attention was given to flexibility, lighting condition and noise reduction in rooms shared by multiple users performing diagnostic tasks as well as regular clinical conferences. Re-engineering workspace ergonomics rely on the integration of new technologies, custom designed cabinets, indirect lighting, sound-absorbent partitioning and geometric arrangement of workstations to allow better privacy while optimizing space occupation. Innovations included adjustable flat monitors, integration of videoconferencing and voice recognition, control monitor and retractable keyboard for optimal space utilization. An overhead compartment protecting the monitors from ambient light is also used as accessory lightbox and rear-view projection screen for conferences.

  17. Effects of dynamic workstation Oxidesk on acceptance, physical activity, mental fitness and work performance.

    Science.gov (United States)

    Groenesteijn, L; Commissaris, D A C M; Van den Berg-Zwetsloot, M; Hiemstra-Van Mastrigt, S

    2016-07-19

    Working in an office environment is characterised by physical inactivity and sedentary behaviour. This behaviour contributes to several health risks in the long run. Dynamic workstations which allow people to combine desk activities with physical activity, may contribute to prevention of these health risks. A dynamic workstation, called Oxidesk, was evaluated to determine the possible contribution to healthy behaviour and the impact on perceived work performance. A field test was conducted with 22 office workers, employed at a health insurance company in the Netherlands. The Oxidesk was well accepted, positively perceived for fitness and the participants maintained their work performance. Physical activity was lower than the activity level required in the Dutch guidelines for sufficient physical activity. Although there was a slight increase in physical activity, the Oxidesk may be helpful in the reducing health risks involved and seems applicable for introduction to office environments.

  18. Teleophthalmology assessment of diabetic retinopathy fundus images: smartphone versus standard office computer workstation.

    Science.gov (United States)

    Kumar, Sajeesh; Wang, Erh-Hsuan; Pokabla, Michael J; Noecker, Robert J

    2012-03-01

    To evaluate the diagnostic capability of a smartphone handset compared with a standard office computer workstation for teleophthalmology fundus photo assessments of diabetic retinopathy. Eligible, consenting participants' fundus images were acquired using a non-mydriatic camera. These images along with other medical data were transmitted 20 miles away through the Internet (gold standard) and also through an iPhone(®) (Apple, Cupertino, CA) to two ophthalmologists, who independently compared the images. The κ coefficient between the gold standard workstation display and iPhone images to detect retinopathy-related changes for both readers was more than 0.9. The image quality of the iPhone was scored high by the ophthalmologists. Ophthalmic images transmitted through both smartphone and Internet techniques match well with each other. Despite current limitations, smartphones could represent as a tool for fundus photo assessments of diabetic retinopathy. Further studies are needed to investigate the economic and clinical feasibility of smartphones in ophthalmology.

  19. SPREADSHEET-BASED PROGRAM FOR ERGONOMIC ADJUSTMENT OF NOTEBOOK COMPUTER AND WORKSTATION SETTINGS.

    Science.gov (United States)

    Nanthavanij, Suebsak; Prae-Arporn, Kanlayanee; Chanjirawittaya, Sorajak; Paripoonyo, Satirajit; Rodloy, Somsak

    2015-06-01

    This paper discusses a computer program, ErgoNBC, which provides suggestions regarding the ergonomic settings of a notebook computer (NBC), workstation components, and selected accessories in order to help computer users to assume an appropriate work posture during the NBC work. From the users' body height, NBC and workstation component data, ErgoNBC computes the recommended tilt angle of NBC base unit, NBC screen angle, distance between the user and NBC, seat height and work surface height. If necessary, the NBC base support, seat cushion and footrest, including their settings, are recommended. An experiment involving twenty-four university students was conducted to evaluate the recommendations provided by ErgoNBC. The Rapid Upper Limb Assessment (RULA) technique was used to analyze their work postures both before and after implementing the Ergo NBC's recommendations. The results clearly showed that ErgoNBC could significantly help to improve the subjects' work postures.

  20. Endovascular abdominal aortic aneurysm sizing and case planning using the TeraRecon Aquarius workstation.

    Science.gov (United States)

    Lee, W Anthony

    2007-01-01

    The gold standard for preoperative evaluation of an aortic aneurysm is a computed tomography angiogram (CTA). Three-dimensional reconstruction and analysis of the computed tomography data set is enormously helpful, and even sometimes essential, in proper sizing and planning for endovascular stent graft repair. To a large extent, it has obviated the need for conventional angiography for morphologic evaluation. The TeraRecon Aquarius workstation (San Mateo, Calif) represents a highly sophisticated but user-friendly platform utilizing a combination of task-specific hardware and software specifically designed to rapidly manipulate large Digital Imaging and Communications in Medicine (DICOM) data sets and provide surface-shaded and multiplanar renderings in real-time. This article discusses the basics of sizing and planning for endovascular abdominal aortic aneurysm repair and the role of 3-dimensional analysis using the TeraRecon workstation.

  1. Workstation-Based Avionics Simulator to Support Mars Science Laboratory Flight Software Development

    Science.gov (United States)

    Henriquez, David; Canham, Timothy; Chang, Johnny T.; McMahon, Elihu

    2008-01-01

    The Mars Science Laboratory developed the WorkStation TestSet (WSTS) to support flight software development. The WSTS is the non-real-time flight avionics simulator that is designed to be completely software-based and run on a workstation class Linux PC. This provides flight software developers with their own virtual avionics testbed and allows device-level and functional software testing when hardware testbeds are either not yet available or have limited availability. The WSTS has successfully off-loaded many flight software development activities from the project testbeds. At the writing of this paper, the WSTS has averaged an order of magnitude more usage than the project's hardware testbeds.

  2. STUDY THE EFFECTIVENESS APPLICATIONS OF FUZZY CONTROLLER WITH TWO ENTRANCES IN THE SYSTEM OF ACTIVE QUEUE MANAGEMENT THE PACKETS IN TCP/IP NETWORKS

    Directory of Open Access Journals (Sweden)

    O. V. Nevdachyna

    2016-01-01

    Full Text Available The paper presents an approach to solving the overloading problem in TCP/IP networks. Offered fuzzy controller with two inputs for system of active queue management packages in TCP/IP networks, and investigated its use in these systems with a random change of traffic load. Proposed controller has two inputs, one of which is the value of the difference between the current queue length and the second – the difference between the current level of usage of the buffer. The output of the fuzzy controller calculates the probability of discarding packet.Mathematical model system of active queue management that is studied is presented in an interactive MATLAB system, in wherein also is demonstrated the processes occurring in the system with a random change of traffic load. The research results show that the AQM-system with fuzzy controller with two entrances stable enough maintains the desired current length the queue for sufficiently small values of the probability of dropping/marking packets (at acceptable size of queue q0= 200 packets, the average probability of dropping / marking is not more than 3,5×10–3 or less 0,35% packets is discarded or marked from the total number of incoming packets. The results obtained will help improve the efficiency of the functioning and operation of TCP / IP networks by increasing data transmission quality. this happens due introduction of the proposed controller at the design of new, more efficient routers for networks to minimize the delay of information.

  3. UNIX based client/server hospital information system.

    Science.gov (United States)

    Nakamura, S; Sakurai, K; Uchiyama, M; Yoshii, Y; Tachibana, N

    1995-01-01

    SMILE (St. Luke's Medical Center Information Linkage Environment) is a HIS which is a client/server system using a UNIX workstation under an open network, LAN(FDDI&10BASE-T). It provides a multivendor environment, high performance with low cost and a user-friendly GUI. However, the client/server architecture with a UNIX workstation does not have the same OLTP environment (ex. TP monor) as the mainframe. So, our system problems and the steps used to solve them were reviewed. Several points that are necessary for a client/server system with a UNIX workstation in the future are presented.

  4. Active Workstations Do Not Impair Executive Function in Young and Middle-Age Adults.

    Science.gov (United States)

    Ehmann, Peter J; Brush, Christopher J; Olson, Ryan L; Bhatt, Shivang N; Banu, Andrea H; Alderman, Brandon L

    2017-05-01

    This study aimed to examine the effects of self-selected low-intensity walking on an active workstation on executive functions (EF) in young and middle-age adults. Using a within-subjects design, 32 young (20.6 ± 2.0 yr) and 26 middle-age (45.6 ± 11.8 yr) adults performed low-intensity treadmill walking and seated control conditions in randomized order on separate days, while completing an EF test battery. EF was assessed using modified versions of the Stroop (inhibition), Sternberg (working memory), Wisconsin Card Sorting (cognitive flexibility), and Tower of London (global EF) cognitive tasks. Behavioral performance outcomes were assessed using composite task z-scores and traditional measures of reaction time and accuracy. Average HR and step count were also measured throughout. The expected task difficulty effects were found for reaction time and accuracy. No significant main effects or interactions as a function of treadmill walking were found for tasks assessing global EF and the three individual EF domains. Accuracy on the Tower of London task was slightly impaired during slow treadmill walking for both age-groups. Middle-age adults displayed longer planning times for more difficult conditions of the Tower of London during walking compared with sitting. A 50-min session of low-intensity treadmill walking on an active workstation resulted in accruing approximately 4500 steps. These findings suggest that executive function performance remains relatively unaffected while walking on an active workstation, further supporting the use of treadmill workstations as an effective approach to increase physical activity and reduce sedentary time in the workplace.

  5. Printed Persian Subword Recognition Using Wavelet Packet Descriptors

    Directory of Open Access Journals (Sweden)

    Samira Nasrollahi

    2013-01-01

    Full Text Available In this paper, we present a new approach to offline OCR (optical character recognition for printed Persian subwords using wavelet packet transform. The proposed algorithm is used to extract font invariant and size invariant features from 87804 subwords of 4 fonts and 3 sizes. The feature vectors are compressed using PCA. The obtained feature vectors yield a pictorial dictionary for which an entry is the mean of each group that consists of the same subword with 4 fonts in 3 sizes. The sets of these features are congregated by combining them with the dot features for the recognition of printed Persian subwords. To evaluate the feature extraction results, this algorithm was tested on a set of 2000 subwords in printed Persian text documents. An encouraging recognition rate of 97.9% is got at subword level recognition.

  6. Modelling of packet traffic with matrix analytic methods

    DEFF Research Database (Denmark)

    Andersen, Allan T.

    1995-01-01

    network services i.e. 800 and 900 calls and advanced mobile communication services. The Markovian Arrival Process (MAP) has been used as a versatile tool to model the packet arrival process. Applying the MAP facilitates the use of Matrix Analytic methods to obtain performance measures associated......-scales. In this study we show that 8-16 state MAPs are able to capture this very variable behaviour over several timescales. The queueing behaviour of these MAPs has been analyzed with Matrix Analytic methods. The results correspond to those obtained by trace driven simulations of measured LAN traffic. It is shown...... process. A heuristic formula for the tail behaviour of a single server queue fed by a superposition of renewal processes has been evaluated. The evaluation was performed by applying Matrix Analytic methods. The heuristic formula has applications in the Call Admission Control (CAC) procedure of the future...

  7. Speech Subvocal Signal Processing using Packet Wavelet and Neuronal Network

    Directory of Open Access Journals (Sweden)

    Luis E. Mendoza

    2013-11-01

    Full Text Available This paper presents the results obtained from the recording, processing and classification of words in the Spanish language by means of the analysis of subvocal speech signals. The processed database has six words (forward, backward, right, left, start and stop. In this work, the signals were sensed with surface electrodes placed on the surface of the throat and acquired with a sampling frequency of 50 kHz. The signal conditioning consisted in: the location of area of interest using energy analysis, and filtering using Discrete Wavelet Transform. Finally, the feature extraction was made in the time-frequency domain using Wavelet Packet and statistical techniques for windowing. The classification was carried out with a backpropagation neural network whose training was performed with 70% of the database obtained. The correct classification rate was 75%±2.

  8. A quantum wave packet study of the ND + D reaction

    Science.gov (United States)

    Surucu, Seda; Tasmanoglu, Gulsen; Akpinar, Sinan

    2012-07-01

    We present the quantum scattering dynamics of the depletion reaction ND ? + D‧ ? N ? + D2 and of the exchange reaction ND ? + D‧ ? ND‧ ? + D using the real wave packet and flux methods and modified NH2 ? potential energy surface (PES). A quantum scattering dynamics calculation is used to study the initial-state-resolved reaction probabilities, integral cross section, rate constants and thermal rate constant for both channels using the centrifugal sudden (CS) approximation for non-zero total angular momentum (J) values. Integral cross sections for both reactions depend strongly on the initial rotational states. In particular, the thermal reaction rate constant for the depletion channel is in good agreement with experimental and semiclassical results.

  9. Quantum oscillations and wave packet revival in conical graphene structure

    Science.gov (United States)

    Sinha, Debabrata; Berche, Bertrand

    2016-03-01

    We present analytical expressions for the eigenstates and eigenvalues of electrons confined in a graphene monolayer in which the crystal symmetry is locally modified by replacing a hexagon by a pentagon, square or heptagon. The calculations are performed in the continuum limit approximation in the vicinity of the Dirac points, solving Dirac equation by freezing out the carrier radial motion. We include the effect of an external magnetic field and show the appearance of Aharonov-Bohm oscillations and find out the conditions of gapped and gapless states in the spectrum. We show that the gauge field due to a disclination lifts the orbital degeneracy originating from the existence of two valleys. The broken valley degeneracy has a clear signature on quantum oscillations and wave packet dynamics.

  10. Use of an anaesthesia workstation barrier device to decrease contamination in a simulated operating room.

    Science.gov (United States)

    Hunter, S; Katz, D; Goldberg, A; Lin, H-M; Pasricha, R; Benesh, G; Le Grand, B; DeMaria, S

    2017-06-01

    Strategies to achieve reductions in perioperative infections have focused on hand hygiene among anaesthestists but have been of limited efficacy. We performed a study in a simulated operating room to determine whether a barrier covering the anaesthesia workstation during induction and intubation might reduce the risk of contamination of the area and possibly, by extension, the patient. Forty-two attending and resident anaesthetists unaware of the study design were enrolled in individual simulation sessions in which they were asked to induce and intubate a human simulator that had been prepared with fluorescent marker in its oropharynx as a marker of potentially pathogenic bacteria. Twenty-one participants were assigned to a control group, whereas the other 21 performed the simulation with a barrier device covering the anaesthesia workstation. After the simulation, an investigator examined 14 target sites with an ultraviolet light to assess spread of the fluorescent marker of contamination to those sites. The difference in rates of contamination between the control group and the barrier group was highly significant, with 44.8% (2.5%) of sites contaminated in the control group vs 19.4% (2.6%) of sites in the barrier group ( P workstation during induction and intubation might reduce contamination of the intraoperative environment.

  11. Tetherless ergonomics workstation to assess nurses' physical workload in a clinical setting.

    Science.gov (United States)

    Smith, Warren D; Nave, Michael E; Hreljac, Alan P

    2011-01-01

    Nurses are at risk of physical injury when moving immobile patients. This paper describes the development and testing of a tetherless ergonomics workstation that is suitable for studying nurses' physical workload in a clinical setting. The workstation uses wearable sensors to record multiple channels of body orientation and muscle activity and wirelessly transmits them to a base station laptop computer for display, storage, and analysis. In preparation for use in a clinical setting, the workstation was tested in a laboratory equipped for multi-camera video motion analysis. The testing included a pilot study of the effect of bed height on student nurses' physical workload while they repositioned a volunteer posing as a bedridden patient toward the head of the bed. Each nurse subject chose a preferred bed height, and data were recorded, in randomized order, with the bed at this height, at 0.1 m below this height, and at 0.1 m above this height. The testing showed that the body orientation recordings made by the wearable sensors agreed closely with those obtained from the video motion analysis system. The pilot study showed the following trends: As the bed height was raised, the nurses' trunk flexion at both thoracic and lumbar sites and lumbar muscle effort decreased, whereas trapezius and deltoid muscle effort increased. These trends will be evaluated by further studies of practicing nurses in the clinical setting.

  12. Frequency of neck and shoulder pain and use of adjustable computer workstation among bankers.

    Science.gov (United States)

    Shabbir, Maryam; Rashid, Sajid; Umar, Bilal; Ahmad, Aqeel; Ehsan, Sarah

    2016-01-01

    Neck and shoulder are the most susceptible areas for developing musculoskeletal symptoms among computer users. The modifiable risk factors for these work related musculoskeletal disorders include physical office environment and psychosocial work related factors. Computer workstation layout had been shown to be an important physical aspect of work environment that influences the upper quadrant symptoms. Our objective was to find the frequency of neck and shoulder pain and use of adjustable computer workstation among bankers of Islamabad/Rawalpindi/Multan. A cross sectional study was conducted and 120 participants were questioned. Purposive sampling technique was used in this study. Maastricht Upper Extremity Questionnaire (MUEQ) was remodeled and important questions were extracted from its detailed version. The tool was then validated by taking expert opinion. Frequencies and percentages were calculated for categorical variables. Pain in the neck during working hours was experienced by 71.67% of the respondents and 48.33% of the participants had experienced shoulder pain during working hours. Adjustable keyboards were used by 16.67% of respondents. Back care material was used by 40% bankers. Adjustable chairs were used by 95.83% of the participants. Only 3% of the bankers did not have chairs with adjustable heights. Chairs with adjustable armrests were used by 25% bankers. Neck and shoulder pain are common occurrences among bankers. Most of the components of workstations of bankers were adjustable but some of them still need attention.

  13. Low Cost Desktop Image Analysis Workstation With Enhanced Interactive User Interface

    Science.gov (United States)

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

    1989-05-01

    A multimodality picture archiving and communication system (PACS) is in routine clinical use in the UCLA Radiology Department. Several types workstations are currently implemented for this PACS. Among them, the Apple Macintosh II personal computer was recently chosen to serve as a desktop workstation for display and analysis of radiological images. This personal computer was selected mainly because of its extremely friendly user-interface, its popularity among the academic and medical community and its low cost. In comparison to other microcomputer-based systems the Macintosh II offers the following advantages: the extreme standardization of its user interface, file system and networking, and the availability of a very large variety of commercial software packages. In the current configuration the Macintosh II operates as a stand-alone workstation where images are imported from a centralized PACS server through an Ethernet network using a standard TCP-IP protocol, and stored locally on magnetic disk. The use of high resolution screens (1024x768 pixels x 8bits) offer sufficient performance for image display and analysis. We focused our project on the design and implementation of a variety of image analysis algorithms ranging from automated structure and edge detection to sophisticated dynamic analysis of sequential images. Specific analysis programs were developed for ultrasound images, digitized angiograms, MRI and CT tomographic images and scintigraphic images.

  14. Pre-analytical workstations: a tool for reducing laboratory errors.

    Science.gov (United States)

    Da Rin, Giorgio

    2009-06-01

    Laboratory testing, a highly complex process commonly called the total testing process (TTP), is usually subdivided into three traditional (pre-, intra-, and post-) analytical phases. The majority of errors in TTP originate in the pre-analytical phase, being due to individual or system design defects. In order to reduce errors in TTP, the pre-analytical phase should therefore be prioritized. In addition to developing procedures, providing training, improving interdepartmental cooperation, information technology and robotics may be a tool to reduce errors in specimen collection and pre-analytical sample handling. It has been estimated that >2000 clinical laboratories worldwide use total or subtotal automation supporting pre-analytic activities, with a high rate of increase compared to 2007; the need to reduce errors seems to be the catalyst for increasing the use of robotics. Automated systems to prevent medical personnel from drawing blood from the wrong patient were introduced commercially in the early 1990s. Correct patient identification and test tube labelling before phlebotomy are of extreme importance for patient safety in TTP, but currently few laboratories are interested in such products. At San Bassiano hospital, the implementation of advanced information technology and robotics in the pre-analytical phase (specimen collection and pre-analytical sample handling) have improved accuracy, and clinical efficiency of the laboratory process and created a TTP that minimizes errors.

  15. Influence of Input Hardware and Work Surface Angle on Upper Limb Posture in a Hybrid Computer Workstation.

    Science.gov (United States)

    Kingston, David C; Riddell, Maureen F; McKinnon, Colin D; Gallagher, Kaitlin M; Callaghan, Jack P

    2016-02-01

    We evaluated the effect of work surface angle and input hardware on upper-limb posture when using a hybrid computer workstation. Offices use sit-stand and/or tablet workstations to increase worker mobility. These workstations may have negative effects on upper-limb joints by increasing time spent in non-neutral postures, but a hybrid standing workstation may improve working postures. Fourteen participants completed office tasks in four workstation configurations: a horizontal or sloped 15° working surface with computer or tablet hardware. Three-dimensional right upper-limb postures were recorded during three tasks: reading, form filling, and writing e-mails. Amplitude probability distribution functions determined the median and range of upper-limb postures. The sloped-surface tablet workstation decreased wrist ulnar deviation by 5° when compared to the horizontal-surface computer when reading. When using computer input devices (keyboard and mouse), the shoulder, elbow, and wrist were closest to neutral joint postures when working on a horizontal work surface. The elbow was 23° and 15° more extended, whereas the wrist was 6° less ulnar deviated, when reading compared to typing forms or e-mails. We recommend that the horizontal-surface computer configuration be used for typing and the sloped-surface tablet configuration be used for intermittent reading tasks in this hybrid workstation. Offices with mobile employees could use this workstation for alternating their upper-extremity postures; however, other aspects of the device need further investigation. © 2015, Human Factors and Ergonomics Society.

  16. Reclaiming "Old" Literacies in the New Literacy Information Age: The Functional Literacies of the Mediated Workstation

    Science.gov (United States)

    Shepherd, Ryan; Goggin, Peter

    2012-01-01

    For many writing faculty, electronic or digital literacies may not play an overtly significant role in their course designs and teaching practices, but these literacies still play a significant role in how students write. Whether or not writing teachers want to accept it, functional computer literacies are an important aspect of teaching writing.…

  17. Stand by Me: Qualitative Insights into the Ease of Use of Adjustable Workstations

    Directory of Open Access Journals (Sweden)

    Jonine Jancey

    2016-08-01

    Full Text Available Background: Office workers sit for more than 80% of the work day making them an important target for work site health promotion interventions to break up prolonged sitting time. Adjustable workstations are one strategy used to reduce prolonged sitting time. This study provides both an employees’ and employers’ perspective into the advantages, disadvantages, practicality and convenience of adjustable workstations and how movement in the office can be further supported by organisations. This qualitative study was part of the Uprising pilot study. Employees were from the intervention arm of a two group (intervention n = 18 and control n = 18 study. Employers were the immediate line-manager of the employee. Data were collected via employee focus groups (n = 17 and employer individual interviews (n = 12. The majority of participants were female (n = 18, had healthy weight, and had a post-graduate qualification. All focus group discussions and interviews were recorded, transcribed verbatim and the data coded according to the content. Qualitative content analysis was conducted. Results: Employee data identified four concepts: enhanced general wellbeing; workability and practicality; disadvantages of the retro-fit; and triggers to stand. Most employees (n = 12 reported enhanced general well-being, workability and practicality included less email exchange and positive interaction (n = 5, while the instability of the keyboard a commonly cited disadvantage. Triggers to stand included time and task based prompts. Employer data concepts included: general health and wellbeing; work engagement; flexibility; employee morale; and injury prevention. Over half of the employers (n = 7 emphasised back care and occupational health considerations as important, as well as increased level of staff engagement and strategies to break up prolonged periods of sitting. Discussion: The focus groups highlight the perceived general health benefits from this short

  18. Vortex packet recovery in a turbulent boundary layer perturbed by an array of cylinders

    Science.gov (United States)

    Tan, Yan Ming; Longmire, Ellen

    2015-11-01

    PIV measurements were acquired in a zero pressure gradient turbulent boundary layer (Reτ = 2500) perturbed by a narrowly spaced (0.2 δ) array of cylinders. Two array heights were considered with one extending to the top of the log region and the other to the top of the boundary layer. Wall-parallel measurements were obtained at three locations in the log region by fixed and flying PIV. The measurement system for flying PIV moves with the flow to track the evolution of structures upstream and downstream of the array. Initially, both arrays disrupt the packets such that none are apparent. Then, packets appear either to recover or re-initiate at some distance downstream. A packet signature was denoted by a low momentum region bounded by counter rotating swirling structures. A low momentum region identification algorithm was applied to both fixed and flying PIV data to quantify packet recovery downstream of the array. The results indicate that packets reappear sooner further from the wall and later closer to the wall for the shorter array supporting the top down notion of packet reorganization proposed by Zheng & Longmire (JFM, 2014). The opposite trend was observed for the taller array whereby packets recovered earlier closer to the wall and later further from the wall.

  19. Optimal Erasure Protection Assignment for Scalable Compressed Data with Small Channel Packets and Short Channel Codewords

    Directory of Open Access Journals (Sweden)

    Johnson Thie

    2004-03-01

    Full Text Available We are concerned with the efficient transmission of scalable compressed data over lossy communication channels. Recent works have proposed several strategies for assigning optimal code redundancies to elements in a scalable data stream under the assumption that all elements are encoded onto a common group of network packets. When the size of the data to be encoded becomes large in comparison to the size of the network packets, such schemes require very long channel codes with high computational complexity. In networks with high loss, small packets are generally more desirable than long packets. This paper proposes a robust strategy for optimally assigning elements of the scalable data to clusters of packets, subject to constraints on packet size and code complexity. Given a packet cluster arrangement, the scheme then assigns optimal code redundancies to the source elements subject to a constraint on transmission length. Experimental results show that the proposed strategy can outperform previously proposed code redundancy assignment policies subject to the above-mentioned constraints, particularly at high channel loss rates.

  20. Experimental evaluation of the impact of packet capturing tools for web services.

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Yung Ryn; Mohapatra, Prasant (University of California, Davis, CA); Chuah, Chen-Nee (University of California, Davis, CA); Chen, Chao-Chih (University of California, Davis, CA)

    2011-10-01

    Network measurement is a discipline that provides the techniques to collect data that are fundamental to many branches of computer science. While many capturing tools and comparisons have made available in the literature and elsewhere, the impact of these packet capturing tools on existing processes have not been thoroughly studied. While not a concern for collection methods in which dedicated servers are used, many usage scenarios of packet capturing now requires the packet capturing tool to run concurrently with operational processes. In this work we perform experimental evaluations of the performance impact that packet capturing process have on web-based services; in particular, we observe the impact on web servers. We find that packet capturing processes indeed impact the performance of web servers, but on a multi-core system the impact varies depending on whether the packet capturing and web hosting processes are co-located or not. In addition, the architecture and behavior of the web server and process scheduling is coupled with the behavior of the packet capturing process, which in turn also affect the web server's performance.