WorldWideScience

Sample records for time sharing mechanism

  1. The Time 'Onewayness' Shared by Quantum Mechanics and Relativity

    International Nuclear Information System (INIS)

    Guzzetta, Giuseppe

    2006-01-01

    The measure of the mutation, or change, any material elementary particle unceasingly undergoes, is defined as that of the displacement of a point moving in a three-dimensional Euclidean space, at the velocity of light, on a trajectory decomposable in a rotation and a translation. The rotation accounts for the spin angular momentum of the particle, the translation for its change of location. Then, an elementary mutation is proportional to an elementary interval of universal time. The connection between space and time is such that the operation of universal time conjugation, that is, the change of sign of t, involves space inversion, so coinciding with the operation currently defined as TCP. It implies that to a given physical process, another equally possible one corresponds in which the sequence of events (that still follow the same time course) is reversed, and actors are the enantiomorphic counterparts (anti-particles instead of particles, and vice versa) of those playing in the first physical process. Since no alternative is left to any elementary particle, that exists in that it undergoes an everlasting mutation, the unidirectionality of time must not be understood as a choice between two alternative directions. Many formalisms of Special Relativity can be derived from the above definition of the mutation of a material elementary particle. Anyhow, some discordances seems to crop out whose discussion is beyond the purpose of the present paper

  2. The People's Time Sharing System

    NARCIS (Netherlands)

    Tanenbaum, A.S.; Benson, W.H.

    1973-01-01

    A set of programs running under a multiprogramming batch operating system on the CDC 6600 which provide remote users with a time sharing service is described. The basis for the system is the ability of a user program to create job control statements during execution, thereby tricking the operating

  3. Universal algorithm of time sharing

    International Nuclear Information System (INIS)

    Silin, I.N.; Fedyun'kin, E.D.

    1979-01-01

    Timesharing system algorithm is proposed for the wide class of one- and multiprocessor computer configurations. Dynamical priority is the piece constant function of the channel characteristic and system time quantum. The interactive job quantum has variable length. Characteristic recurrent formula is received. The concept of the background job is introduced. Background job loads processor if high priority jobs are inactive. Background quality function is given on the base of the statistical data received in the timesharing process. Algorithm includes optimal trashing off procedure for the jobs replacements in the memory. Sharing of the system time in proportion to the external priorities is guaranteed for the all active enough computing channels (back-ground too). The fast answer is guaranteed for the interactive jobs, which use small time and memory. The external priority control is saved for the high level scheduler. The experience of the algorithm realization on the BESM-6 computer in JINR is discussed

  4. 47 CFR 73.1715 - Share time.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Share time. 73.1715 Section 73.1715... Rules Applicable to All Broadcast Stations § 73.1715 Share time. Operation is permitted by two or more... considered part of their licenses. (a) If the licenses of stations authorized to share time do not specify...

  5. Risk sharing relations and enforcement mechanisms

    NARCIS (Netherlands)

    Barr, A.; Dekker, M.; Fafchamps, M.

    2008-01-01

    We investigate whether the set of available enforcement mechanisms affects the formation of risk sharing relations by applying dyadic regression analysis to data from a specifically designed behavioural experiment, two surveys and a genealogical mapping exercise. During the experiment participants

  6. Modeling of the time sharing for lecturers

    Directory of Open Access Journals (Sweden)

    E. Yu. Shakhova

    2017-01-01

    Full Text Available In the context of modernization of the Russian system of higher education, it is necessary to analyze the working time of the university lecturers, taking into account both basic job functions as the university lecturer, and others.The mathematical problem is presented for the optimal working time planning for the university lecturers. The review of the documents, native and foreign works on the study is made. Simulation conditions, based on analysis of the subject area, are defined. Models of optimal working time sharing of the university lecturers («the second half of the day» are developed and implemented in the system MathCAD. Optimal solutions have been obtained.Three problems have been solved:1 to find the optimal time sharing for «the second half of the day» in a certain position of the university lecturer;2 to find the optimal time sharing for «the second half of the day» for all positions of the university lecturers in view of the established model of the academic load differentiation;3 to find the volume value of the non-standardized part of time work in the department for the academic year, taking into account: the established model of an academic load differentiation, distribution of the Faculty number for the positions and the optimal time sharing «the second half of the day» for the university lecturers of the department.Examples are given of the analysis results. The practical application of the research: the developed models can be used when planning the working time of an individual professor in the preparation of the work plan of the university department for the academic year, as well as to conduct a comprehensive analysis of the administrative decisions in the development of local university regulations.

  7. Knowledge-Sharing Hostility and Governance Mechanisms

    DEFF Research Database (Denmark)

    Husted, Kenneth; Michailova, Snejina; Minbaeva, Dana

    2012-01-01

    Purpose – This paper aims at further developing and empirically examining the concept of knowledge-sharing hostility. It seeks to analyze reasons for hoarding knowledge, reasons for rejecting external knowledge, and attitudes towards mistakes, as well as the influence of these factors on actual k...

  8. Time in quantum mechanics

    CERN Document Server

    Mayato, R; Egusquiza, I

    2002-01-01

    The treatment of time in quantum mechanics is still an important and challenging open question in the foundation of the theory. This book describes the problems, and the attempts and achievements in defining, formalizing and measuring different time quantities in quantum theory, such as the parametric (clock) time, tunneling times, decay times, dwell times, delay times, arrival times or jump times. This multiauthored book, written as an introductory guide for the non-initiated as well as a useful source of information for the expert, covers many of the open questions. A brief historical overview is to be found in the introduction. It is followed by 12 chapters devoted to conceptual and theoretical investigations as well as experimental issues in quantum-mechanical time measurements. This unique monograph should attract physicists as well as philosophers of science working in the foundations of quantum physics.

  9. Time Dependent Quantum Mechanics

    OpenAIRE

    Morrison, Peter G.

    2012-01-01

    We present a systematic method for dealing with time dependent quantum dynamics, based on the quantum brachistochrone and matrix mechanics. We derive the explicit time dependence of the Hamiltonian operator for a number of constrained finite systems from this formalism. Once this has been achieved we go on to calculate the wavevector as a function of time, in order to demonstrate the use of matrix methods with respect to several concrete examples. Interesting results are derived for elliptic ...

  10. Design principles of a resource sharing real-time-system

    International Nuclear Information System (INIS)

    Gliss, B.

    1978-01-01

    Criteria for developing a resource sharing real time system are given. Resource sharing necessitates extra precautions for guaranteeing stable operating conditions. Some relevant measures to insure reliability and maintainability of the system are discussed. (Auth.)

  11. Time Asymmetric Quantum Mechanics

    Directory of Open Access Journals (Sweden)

    Arno R. Bohm

    2011-09-01

    Full Text Available The meaning of time asymmetry in quantum physics is discussed. On the basis of a mathematical theorem, the Stone-von Neumann theorem, the solutions of the dynamical equations, the Schrödinger equation (1 for states or the Heisenberg equation (6a for observables are given by a unitary group. Dirac kets require the concept of a RHS (rigged Hilbert space of Schwartz functions; for this kind of RHS a mathematical theorem also leads to time symmetric group evolution. Scattering theory suggests to distinguish mathematically between states (defined by a preparation apparatus and observables (defined by a registration apparatus (detector. If one requires that scattering resonances of width Γ and exponentially decaying states of lifetime τ=h/Γ should be the same physical entities (for which there is sufficient evidence one is led to a pair of RHS's of Hardy functions and connected with it, to a semigroup time evolution t_0≤t<∞, with the puzzling result that there is a quantum mechanical beginning of time, just like the big bang time for the universe, when it was a quantum system. The decay of quasi-stable particles is used to illustrate this quantum mechanical time asymmetry. From the analysis of these processes, we show that the properties of rigged Hilbert spaces of Hardy functions are suitable for a formulation of time asymmetry in quantum mechanics.

  12. Interactively human: Sharing time, constructing materiality.

    Science.gov (United States)

    Roepstorff, Andreas

    2013-06-01

    Predictive processing models of cognition are promising an elegant way to unite action, perception, and learning. However, in the current formulations, they are species-unspecific and have very little particularly human about them. I propose to examine how, in this framework, humans can be able to massively interact and to build shared worlds that are both material and symbolic.

  13. Library Information System Time-Sharing (LISTS) Project. Final Report.

    Science.gov (United States)

    Black, Donald V.

    The Library Information System Time-Sharing (LISTS) experiment was based on three innovations in data processing technology: (1) the advent of computer time-sharing on third-generation machines, (2) the development of general-purpose file-management software and (3) the introduction of large, library-oriented data bases. The main body of the…

  14. Sojourn time asymptotics in processor-sharing queues

    NARCIS (Netherlands)

    Borst, S.C.; Núñez Queija, R.; Zwart, B.

    2006-01-01

    Over the past few decades, the Processor-Sharing (PS) discipline has attracted a great deal of attention in the queueing literature. While the PS paradigm emerged in the sixties as an idealization of round-robin scheduling in time-shared computer systems, it has recently captured renewed interest as

  15. Sharing Ideas: Tough Times Encourage Colleges to Collaborate

    Science.gov (United States)

    Fain, Paul; Blumenstyk, Goldie; Sander, Libby

    2009-01-01

    Tough times are encouraging colleges to share resources in a variety of areas, including campus security, research, and degree programs. Despite its veneer of cooperation, higher education is a competitive industry, where resource sharing is eyed warily. But the recession is chipping away at that reluctance, and institutions are pursuing…

  16. Pediatric Traumatic Brain Injury and Autism: Elucidating Shared Mechanisms

    Directory of Open Access Journals (Sweden)

    Rahul Singh

    2016-01-01

    Full Text Available Pediatric traumatic brain injury (TBI and autism spectrum disorder (ASD are two serious conditions that affect youth. Recent data, both preclinical and clinical, show that pediatric TBI and ASD share not only similar symptoms but also some of the same biologic mechanisms that cause these symptoms. Prominent symptoms for both disorders include gastrointestinal problems, learning difficulties, seizures, and sensory processing disruption. In this review, we highlight some of these shared mechanisms in order to discuss potential treatment options that might be applied for each condition. We discuss potential therapeutic and pharmacologic options as well as potential novel drug targets. Furthermore, we highlight advances in understanding of brain circuitry that is being propelled by improved imaging modalities. Going forward, advanced imaging will help in diagnosis and treatment planning strategies for pediatric patients. Lessons from each field can be applied to design better and more rigorous trials that can be used to improve guidelines for pediatric patients suffering from TBI or ASD.

  17. Principles of discrete time mechanics

    CERN Document Server

    Jaroszkiewicz, George

    2014-01-01

    Could time be discrete on some unimaginably small scale? Exploring the idea in depth, this unique introduction to discrete time mechanics systematically builds the theory up from scratch, beginning with the historical, physical and mathematical background to the chronon hypothesis. Covering classical and quantum discrete time mechanics, this book presents all the tools needed to formulate and develop applications of discrete time mechanics in a number of areas, including spreadsheet mechanics, classical and quantum register mechanics, and classical and quantum mechanics and field theories. A consistent emphasis on contextuality and the observer-system relationship is maintained throughout.

  18. Time in Quantum Mechanics

    International Nuclear Information System (INIS)

    Reznik, B.

    1999-01-01

    Time plays an unusual role in quantum theory, and the measurement of time is very different from the measurement of other physical qualities associated with a particle. As an example, the measurability of when something occurred is conceptually fraught with difficulties within the theory. Time must be measured by clocks, and one must somehow cause the occurrence of the event of interest to interact with a clock to record when that event occurred. But that interaction carries with it an inevitable perturbation of the event itself. I will argue that in addition to the usual ΔtΔE > ℎ associated with the accuracy of any clock, there is an additional ΔtE > ℎ uncertainty in the measurement of the time of arrival of a particle. Furthermore this constraint arises because the timing device can itself prevent the event from ever occurring at all. I will compare time measurements involving physical clocks, with attempts to construct a time operator and describe new difficulties associated with the latter approach

  19. Incentive Mechanism Model Design for Sharing of Information Resources in Rural Areas

    OpenAIRE

    Gao, Xirong; Shan, Lingling

    2013-01-01

    In order to solve the issues concerning the cross-unit sharing of information resources in rural areas, we analyze the incentive problem of the sharing of information resources in rural areas using the incentive theory method; establish corresponding incentive mechanism model (It is divided into positive incentive model and negative incentive model, and only when the two models guarantee each other and are used at the same time can they be effective). Based on this, we put forward the institu...

  20. Time Out with Half-Time: Job Sharing in the Nineties.

    Science.gov (United States)

    Turner, Linda

    1996-01-01

    Job sharing is a form of employment often overlooked by the average worker. Eight women were interviewed for this qualitative research study on the benefits and drawbacks of job sharing. Rather than simply allowing more time for them to spend with their children or on domestic chores, job sharing provided unanticipated opportunities to enjoy a…

  1. Time-sharing visual and auditory tracking tasks

    Science.gov (United States)

    Tsang, Pamela S.; Vidulich, Michael A.

    1987-01-01

    An experiment is described which examined the benefits of distributing the input demands of two tracking tasks as a function of task integrality. Visual and auditory compensatory tracking tasks were utilized. Results indicate that presenting the two tracking signals in two input modalities did not improve time-sharing efficiency. This was attributed to the difficulty insensitivity phenomenon.

  2. GRAPHIC, time-sharing magnet design computer programs at Argonne

    International Nuclear Information System (INIS)

    Lari, R.J.

    1974-01-01

    This paper describes three magnet design computer programs in use at the Zero Gradient Synchrotron of Argonne National Laboratory. These programs are used in the time sharing mode in conjunction with a Tektronix model 4012 graphic display terminal. The first program in called TRIM, the second MAGNET, and the third GFUN. (U.S.)

  3. Sojourn times in finite-capacity processor-sharing queues

    NARCIS (Netherlands)

    Borst, S.C.; Boxma, O.J.; Hegde, N.

    2005-01-01

    Motivated by the need to develop simple parsimonious models for evaluating the performance of wireless data systems, we consider finite-capacity processor-sharing systems. For such systems, we analyze the sojourn time distribution, which presents a useful measure for the transfer delay of documents

  4. Controlling shareholders and market timing in share issuance

    NARCIS (Netherlands)

    Urzua Infante, F.; Larrain, B.

    2013-01-01

    We examine market timing in the equity issuance of firms controlled by large shareholders using a hand-collected data set of controlling shareholders' ownership stakes in Chile between 1990 and 2009. When a firm issues shares, the controlling shareholder can either maintain or change his ownership

  5. Quantum mechanics with quantum time

    International Nuclear Information System (INIS)

    Kapuscik, E.

    1984-01-01

    Using a non-canonical Lie structure of classical mechanics a new algebra of quantum mechanical observables is constructed. The new algebra, in addition to the notion of classical time, makes it possible to introduce the notion of quantum time. A new type of uncertainty relation is derived. (author)

  6. A secure and efficient audit mechanism for dynamic shared data in cloud storage.

    Science.gov (United States)

    Kwon, Ohmin; Koo, Dongyoung; Shin, Yongjoo; Yoon, Hyunsoo

    2014-01-01

    With popularization of cloud services, multiple users easily share and update their data through cloud storage. For data integrity and consistency in the cloud storage, the audit mechanisms were proposed. However, existing approaches have some security vulnerabilities and require a lot of computational overheads. This paper proposes a secure and efficient audit mechanism for dynamic shared data in cloud storage. The proposed scheme prevents a malicious cloud service provider from deceiving an auditor. Moreover, it devises a new index table management method and reduces the auditing cost by employing less complex operations. We prove the resistance against some attacks and show less computation cost and shorter time for auditing when compared with conventional approaches. The results present that the proposed scheme is secure and efficient for cloud storage services managing dynamic shared data.

  7. A Secure and Efficient Audit Mechanism for Dynamic Shared Data in Cloud Storage

    Science.gov (United States)

    2014-01-01

    With popularization of cloud services, multiple users easily share and update their data through cloud storage. For data integrity and consistency in the cloud storage, the audit mechanisms were proposed. However, existing approaches have some security vulnerabilities and require a lot of computational overheads. This paper proposes a secure and efficient audit mechanism for dynamic shared data in cloud storage. The proposed scheme prevents a malicious cloud service provider from deceiving an auditor. Moreover, it devises a new index table management method and reduces the auditing cost by employing less complex operations. We prove the resistance against some attacks and show less computation cost and shorter time for auditing when compared with conventional approaches. The results present that the proposed scheme is secure and efficient for cloud storage services managing dynamic shared data. PMID:24959630

  8. Synchronization resources in heterogeneous environments: Time-sharing, real-time and Java

    International Nuclear Information System (INIS)

    Pereira, A.; Vega, J.; Pacios, L.; Sanchez, E.; Portas, A.

    2006-01-01

    The asynchronous event distribution system (AEDS) was built to provide synchronization resources within the TJ-II local area network. It is a software system developed to add 'soft synchronization' capabilities to the TJ-II data acquisition, control and analysis environments. 'Soft synchronization' signifies that AEDS is not a real-time system. In fact, AEDS is based on TCP/IP over ETHERNET networks. However, its response time is adequate for practical purposes when synchronization requirements can support some delay between event dispatch and message reception. Event broadcasters (or synchronization servers in AEDS terminology) are Windows computers. Destination computers (or synchronization clients) were also Windows machines in the first version of AEDS. However, this fact imposed a very important limitation on synchronization capabilities. To overcome this situation, synchronization clients for different environments have been added to AEDS: for time-sharing operating systems (Unix and Linux), real-time operating systems (OS-9 and VxWorks) and Java applications. These environments have different synchronization primitives, requiring different approaches to provide the required uniform functionality. This has been achieved with POSIX thread library synchronization primitives (mutex and condition variables) on Unix/Linux systems, IPC mechanisms for concurrent processes on OS-9 and VxWorks real-time operating systems, and 'synchronized-wait/notify' primitives on Java virtual machines

  9. Synchronization resources in heterogeneous environments: Time-sharing, real-time and Java

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, A. [Asociacion EURATOM/CIEMAT para Fusion, CIEMAT Edificio 66, Avda. Complutense, 22, 28040 Madrid (Spain)]. E-mail: augusto.pereira@ciemat.es; Vega, J. [Asociacion EURATOM/CIEMAT para Fusion, CIEMAT Edificio 66, Avda. Complutense, 22, 28040 Madrid (Spain); Pacios, L. [Asociacion EURATOM/CIEMAT para Fusion, CIEMAT Edificio 66, Avda. Complutense, 22, 28040 Madrid (Spain); Sanchez, E. [Asociacion EURATOM/CIEMAT para Fusion, CIEMAT Edificio 66, Avda. Complutense, 22, 28040 Madrid (Spain); Portas, A. [Asociacion EURATOM/CIEMAT para Fusion, CIEMAT Edificio 66, Avda. Complutense, 22, 28040 Madrid (Spain)

    2006-07-15

    The asynchronous event distribution system (AEDS) was built to provide synchronization resources within the TJ-II local area network. It is a software system developed to add 'soft synchronization' capabilities to the TJ-II data acquisition, control and analysis environments. 'Soft synchronization' signifies that AEDS is not a real-time system. In fact, AEDS is based on TCP/IP over ETHERNET networks. However, its response time is adequate for practical purposes when synchronization requirements can support some delay between event dispatch and message reception. Event broadcasters (or synchronization servers in AEDS terminology) are Windows computers. Destination computers (or synchronization clients) were also Windows machines in the first version of AEDS. However, this fact imposed a very important limitation on synchronization capabilities. To overcome this situation, synchronization clients for different environments have been added to AEDS: for time-sharing operating systems (Unix and Linux), real-time operating systems (OS-9 and VxWorks) and Java applications. These environments have different synchronization primitives, requiring different approaches to provide the required uniform functionality. This has been achieved with POSIX thread library synchronization primitives (mutex and condition variables) on Unix/Linux systems, IPC mechanisms for concurrent processes on OS-9 and VxWorks real-time operating systems, and 'synchronized-wait/notify' primitives on Java virtual machines.

  10. How to handle part-time, flex-time, and job-sharing employees.

    Science.gov (United States)

    Sachs, L

    2001-01-01

    Offering employment structures other than traditional full-time positions in your practice can help you draw excellent job applicants and also can enable you to increase morale, job satisfaction, and productivity. However, there are many decisions you must make when offering a part-time, flex-time, or job-sharing position. This article explores the pros and cons of offering alternative job structures. It suggests ways to make part-time, flex-time, or job-sharing positions work most effectively, both for the employee and for your practice. In addition, this article suggests which positions are best suited to alternative structures.

  11. Sojourn time tails in processor-sharing systems

    NARCIS (Netherlands)

    Egorova, R.R.

    2009-01-01

    The processor-sharing discipline was originally introduced as a modeling abstraction for the design and performance analysis of the processing unit of a computer system. Under the processor-sharing discipline, all active tasks are assumed to be processed simultaneously, receiving an equal share of

  12. Absolute symbolic addressing, a structure making time-sharing easier

    International Nuclear Information System (INIS)

    Debraine, P.

    1968-08-01

    Time-sharing of computers asks for a certain number of conditions, particularly, an efficient dynamic loading of programs and data. This paper indicates a paging method making linkages with a minimum of table-looking operations. The principle is to use associative memory registers for calling blocks of physical memory, the block address being given by the concatenation of a file number (located in a base register) and a page number (located in the instruction proper). The position within the block is given by a displacement located in the instruction. A second associated base register contains the local part (page number + displacement) of the base address. This extended base register system allows executing programs in a very large programming complex without loss of time. The addresses are fixed at assembly time and the blocks can be loaded anywhere without modification for execution. The various problems associated with the execution of complex programs are presented in this context and shown to be easily solved by the proposed system, the realization of which would be very easy starting from the computer structures existing now. (author) [fr

  13. Relativistic mechanics, time and inertia

    International Nuclear Information System (INIS)

    Kilmister, C.W.; Tocaci, E.

    1985-01-01

    This book offers a thought-provoking approach to the fundamentals of relativity, and is structured to provide a clear-cut introduction to the essentials of relativistic mechanics. It seeks to emphasize the sensible content of concepts, to improve on their inherent or often forgotten fuzziness, and to explore prospects for their further exploitation. The work also provides an analysis conducive to a rigorous, normative definition of Time, which is seen as a synthesis of universal motion, instrumental in defining a general measure to transformations, and as a sufficient reason to suppose that the speed of light must be the same in all inertial reference frames - hence showing this cardinal postulate to be a demonstrable truth. Moreover it provides an augmented perception of what inertial vs. non-inertial systems are. In addition, the book offers a natural, time-like interpretation of Space that departs from the usual converse approach; it offers a self-consistent proposal to rationalize the axiomatic grounds of mechanics, based on a single postulate in conjunction with the overall approach developed. (author). refs.; figs.; tabs

  14. A Qualitative Analysis of Real-Time Continuous Glucose Monitoring Data Sharing with Care Partners: To Share or Not to Share?

    Science.gov (United States)

    Litchman, Michelle L; Allen, Nancy A; Colicchio, Vanessa D; Wawrzynski, Sarah E; Sparling, Kerri M; Hendricks, Krissa L; Berg, Cynthia A

    2018-01-01

    Little research exists regarding how real-time continuous glucose monitoring (RT-CGM) data sharing plays a role in the relationship between patients and their care partners. To (1) identify the benefits and challenges related to RT-CGM data sharing from the patient and care partner perspective and (2) to explore the number and type of individuals who share and follow RT-CGM data. This qualitative content analysis was conducted by examining publicly available blogs focused on RT-CGM and data sharing. A thematic analysis of blogs and associated comments was conducted. A systematic appraisal of personal blogs examined 39 blogs with 206 corresponding comments. The results of the study provided insight about the benefits and challenges related to individuals with diabetes sharing their RT-CGM data with a care partner(s). The analysis resulted in three themes: (1) RT-CGM data sharing enhances feelings of safety, (2) the need to communicate boundaries to avoid judgment, and (3) choice about sharing and following RT-CGM data. RT-CGM data sharing occurred within dyads (n = 46), triads (n = 15), and tetrads (n = 2). Adults and children with type 1 diabetes and their care partners are empowered by the ability to share and follow RT-CGM data. Our findings suggest that RT-CGM data sharing between an individual with diabetes and their care partner can complicate relationships. Healthcare providers need to engage patients and care partners in discussions about best practices related to RT-CGM sharing and following to avoid frustrations within the relationship.

  15. Depression and Chronic Liver Diseases: Are There Shared Underlying Mechanisms?

    Directory of Open Access Journals (Sweden)

    Xiaoqin Huang

    2017-05-01

    Full Text Available The occurrence of depression is higher in patients with chronic liver disease (CLD than that in the general population. The mechanism described in previous studies mainly focused on inflammation and stress, which not only exists in CLD, but also emerges in common chronic diseases, leaving the specific mechanism unknown. This review was to summarize the prevalence and risk factors of depression in CLD including chronic hepatitis B, chronic hepatitis, alcoholic liver disease, and non-alcoholic fatty liver disease, and to point out the possible underlying mechanism of this potential link. Clarifying the origins of this common comorbidity (depression and CLD may provide more information to understand both diseases.

  16. Scalable Spectrum Sharing Mechanism for Local Area Networks Deployment

    DEFF Research Database (Denmark)

    Da Costa, Gustavo Wagner Oliveira; Cattoni, Andrea Fabio; Kovacs, Istvan Zsolt

    2010-01-01

    in high mobility conditions. These goals can be only achieved through the use highly Optimized Local Area (OLA) access networks, operating at low range and low power transmissions. The efficient sharing of radio resources among OLAs will be very difficult to achieve with a traditional network planning......The availability on the market of powerful and lightweight mobile devices has led to a fast diffusion of mobile services for end users and the trend is shifting from voice based services to multimedia contents distribution. The current access networks are, however, able to support relatively low...... data rates and with limited Quality of Service (QoS). In order to extend the access to high data rate services to wireless users, the International Telecommunication Union (ITU) established new requirements for future wireless communication technologies of up to 1Gbps in low mobility and up to 100Mbps...

  17. Delayed and accelerated aging share common longevity assurance mechanisms

    NARCIS (Netherlands)

    Schumacher, B.; van der Pluijm, I.; Moorhouse, M.J.; Kosteas, T.; Robinson, A.R.; Suh, Y.; Breit, T.M.; van Steeg, H.; Niedernhofer, L.J.; van IJcken, W.; Bartke, A.; Spindler, S.R.; Hoeijmakers, J.H.J.; van der Horst, G.T.J.; Garinis, G.A.

    2008-01-01

    Mutant dwarf and calorie-restricted mice benefit from healthy aging and unusually long lifespan. In contrast, mouse models for DNA repair-deficient progeroid syndromes age and die prematurely. To identify mechanisms that regulate mammalian longevity, we quantified the parallels between the

  18. Delayed and accelerated aging share common longevity assurance mechanisms

    NARCIS (Netherlands)

    B. Schumacher (Björn); I. van der Pluijm (Ingrid); M.J. Moorhouse (Michael); T. Kosteas (Theodore); A.R. Robinson (Andria Rasile); Y. Suh (Yousin); T.M. Breit (Timo); H. van Steeg (Harry); L.J. Niedernhofer (Laura); W.F.J. van IJcken (Wilfred); A. Bartke (Andrzej); S.R. Spindler (Stephen); J.H.J. Hoeijmakers (Jan); G.T.J. van der Horst (Gijsbertus); G.A. Garinis (George)

    2008-01-01

    textabstractMutant dwarf and calorie-restricted mice benefit from healthy aging and unusually long lifespan. In contrast, mouse models for DNA repair-deficient progeroid syndromes age and die prematurely. To identify mechanisms that regulate mammalian longevity, we quantified the parallels between

  19. Vibrant times for mechanical metamaterials

    DEFF Research Database (Denmark)

    Christensen, Johan; Kadic, Muamer; Kraft, Oliver

    2015-01-01

    Metamaterials are man-made designer matter that obtains its unusual effective properties by structure rather than chemistry. Building upon the success of electromagnetic and acoustic metamaterials, researchers working on mechanical metamaterials strive at obtaining extraordinary or extreme...... mass density, negative modulus, pentamode, anisotropic mass density, Origami, nonlinear, bistable, and reprogrammable mechanical metamaterials....

  20. Shared mechanisms of perceptual learning and decision making.

    Science.gov (United States)

    Law, Chi-Tat; Gold, Joshua I

    2010-04-01

    Perceptual decisions require the brain to weigh noisy evidence from sensory neurons to form categorical judgments that guide behavior. Here we review behavioral and neurophysiological findings suggesting that at least some forms of perceptual learning do not appear to affect the response properties of neurons that represent the sensory evidence. Instead, improved perceptual performance results from changes in how the sensory evidence is selected and weighed to form the decision. We discuss the implications of this idea for possible sites and mechanisms of training-induced improvements in perceptual processing in the brain. Copyright © 2009 Cognitive Science Society, Inc.

  1. A mechanism for frequency modulation in songbirds shared with humans.

    Science.gov (United States)

    Amador, Ana; Margoliash, Daniel

    2013-07-03

    In most animals that vocalize, control of fundamental frequency is a key element for effective communication. In humans, subglottal pressure controls vocal intensity but also influences fundamental frequency during phonation. Given the underlying similarities in the biomechanical mechanisms of vocalization in humans and songbirds, songbirds offer an attractive opportunity to study frequency modulation by pressure. Here, we present a novel technique for dynamic control of subsyringeal pressure in zebra finches. By regulating the opening of a custom-built fast valve connected to the air sac system, we achieved partial or total silencing of specific syllables, and could modify syllabic acoustics through more complex manipulations of air sac pressure. We also observed that more nuanced pressure variations over a limited interval during production of a syllable concomitantly affected the frequency of that syllable segment. These results can be explained in terms of a mathematical model for phonation that incorporates a nonlinear description for the vocal source capable of generating the observed frequency modulations induced by pressure variations. We conclude that the observed interaction between pressure and frequency was a feature of the source, not a result of feedback control. Our results indicate that, beyond regulating phonation or its absence, regulation of pressure is important for control of fundamental frequencies of vocalizations. Thus, although there are separate brainstem pathways for syringeal and respiratory control of song production, both can affect airflow and frequency. We hypothesize that the control of pressure and frequency is combined holistically at higher levels of the vocalization pathways.

  2. On time in quantum mechanics

    International Nuclear Information System (INIS)

    Vona, Nicola

    2014-01-01

    Although time measurements are routinely performed in laboratories, their theoretical description is still an open problem. Similarly, also the validity and the status of the energy-time uncertainty relation is unsettled. In the first part of this work the necessity of positive operator valued measures (POVM) as descriptions of every quantum experiment is reviewed, as well as the suggestive role played by the probability current in time measurements. Furthermore, it is shown that no POVM exists, which approximately agrees with the probability current on a very natural set of wave functions; nevertheless, the choice of the set is crucial, and on more restrictive sets the probability current does provide a good arrival time prediction. Some ideas to experimentally detect quantum effects in time measurements are discussed. In the second part of the work the energy-time uncertainty relation is considered, in particular for a model of alpha decay for which the variance of the energy can be calculated explicitly, and the variance of time can be estimated. This estimate is tight for systems with long lifetimes, in which case the uncertainty relation is shown to be satisfied. Also the linewidth-lifetime relation is shown to hold, but contrary to the common expectation, it is found that the two relations behave independently, and therefore it is not possible to interpret one as a consequence of the other. To perform the mentioned analysis quantitative scattering estimates are necessary. To this end, bounds of the form parallel 1 R e -iHt ψ parallel (2)/(2)≤Ct -3 have been derived, where ψ denotes the initial state, H the Hamiltonian, R a positive constant, and C is explicitly known. As intermediate step, bounds on the derivatives of the S-matrix in the form parallel 1 K S (n) parallel ∞ ≤C n,K have been established, with n=1,2,3, and the constants C n,K explicitly known.

  3. Internet Data Distribution – extending real-time data sharing throughout the Americas

    Directory of Open Access Journals (Sweden)

    T. Yoksas

    2006-01-01

    Full Text Available The Unidata Program Center (Unidata of the University Corporation of Atmospheric Research (UCAR is involved in three international collaborations whose goals are extension of real-time data delivery-to and sharing-of locally held datasets-by educational institutions throughout the Americas. These efforts are based on the use of Unidata's Internet Data Distribution (IDD system which is built on top of its proven Local Data Manager Version 6 (LDM-6 technology. The Unidata IDD is an event-driven network of cooperating Unidata LDM servers that distributes discipline-neutral data products in near real-time over wide-area networks. The IDD, a collaboration of over 150 mostly North American institutions of higher education, has been the primary source of real-time atmospheric science data for the US university community for over a decade,. In addition to providing a highly reliable mechanism for delivering real-time data, the IDD allows users to easily share locally held datasets.

  4. A Resource Sharing Mechanism for Sustainable Production in the Garment Industry

    Directory of Open Access Journals (Sweden)

    Ke Ma

    2017-12-01

    Full Text Available With the development of mass customization, the traditional garment production model needs to be optimized to have a more sustainable structure. To meet demand for flexibility, low-cost, and high-efficiency, an innovative resource sharing mechanism was proposed in this paper to form a new sustainable type of garment production. Different from the individual production in traditional models, the new mechanism involves resources being shared among various manufacturers. The tradeoff between positive and negative effects of the proposed mechanism is a key issue for sustainable production. In the present study, an overall sustainable index, integrating four production performance indicators, was defined on the basis of an Analytical Network Process to assess various production scenarios. According to the discrete-event simulation results of the different scenarios, we found that garment manufacturers could obtain comprehensive improvements in sustainable production by implementing the proposed resource sharing mechanism under the threshold of an increasing production failure rate.

  5. Analysis of Information Sharing Mechanism in the Food Industry Green Supply Chain Management and Operation Process

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    In order to effectively address the issues of environmental pollution and food safety in food industry,the green supply chain management should be used in the food industry.However,information sharing is the basis of supply chain management.For this purpose,on the basis of describing the connotation of food industry green supply chain management,the paper introduces the contents and the effects of information sharing mode in detail.It focuses on the barriers of the implementation of information-sharing mechanisms in the food industry green supply chain management and operation process and analyzes the necessity of using information sharing mechanism among the members of the food industry green supply chain management mode by game theory,so as to strengthen the competitiveness of enterprises through supply chain management.

  6. Research on the Mechanism of Cross Organizational Knowledge Sharing in BIM Competitive Environment

    Directory of Open Access Journals (Sweden)

    Zhong Wei

    2017-01-01

    Full Text Available Co-opetition under the environment of BIM implementation process because the level is not high resulting in the project BIM application value of incomplete knowledge sharing among organizations, thus establishing good knowledge can effectively solve this problem and achieve the overall benefit and benefit sharing mechanism in the project organization. This paper defines five competing modes according to the competing degree of organization between different BIM applications, including imperfect competition, competition, competition and cooperation, full cooperation and cooperation, and put forward the conceptual model and related assumptions. Analysis of the effect of path and effect of project determined in BIM application mode, the concurrence of knowledge sharing, efficiency and overall efficiency of the project within the organization through the survey and empirical results, and according to the proposed contract, the distribution of benefits and work three kinds of knowledge sharing mechanism implementation path.

  7. Shared Leadership Improves Team Novelty: The Mechanism and Its Boundary Condition

    Science.gov (United States)

    Sun, Xiaomin; Jie, Yuan; Wang, Yilu; Xue, Gang; Liu, Yan

    2016-01-01

    Previous research has revealed the significant impact of shared leadership on team creativity, yet the mechanism underlying this relationship has rarely been investigated. The current research examined how shared leadership influenced team creativity (novelty and usefulness) across 3 studies using both long-term project teams and temporal task teams in the laboratory. The results showed that shared leadership enhanced the novelty dimension of team creativity by improving constructive controversy. Furthermore, team goal orientation moderated this effect. The indirect effect of constructive controversy holds for teams with learning goal orientation but not for those with performance goal orientation. Such patterns were not found in the usefulness dimension of team creativity. PMID:28066289

  8. Symmetries in discrete-time mechanics

    International Nuclear Information System (INIS)

    Khorrami, M.

    1996-01-01

    Based on a general formulation for discrete-time quantum mechanics, introduced by M. Khorrami (Annals Phys. 224 (1995), 101), symmetries in discrete-time quantum mechanics are investigated. It is shown that any classical continuous symmetry leads to a conserved quantity in classical mechanics, as well as quantum mechanics. The transformed wave function, however, has the correct evolution if and only if the symmetry is nonanomalous. Copyright copyright 1996 Academic Press, Inc

  9. Sharing Steps in the Workplace: Changing Privacy Concerns Over Time

    DEFF Research Database (Denmark)

    Jensen, Nanna Gorm; Shklovski, Irina

    2016-01-01

    study of a Danish workplace participating in a step counting campaign. We find that concerns of employees who choose to participate and those who choose not to differ. Moreover, privacy concerns of participants develop and change over time. Our findings challenge the assumption that consumers...

  10. Tunneling time in space fractional quantum mechanics

    Science.gov (United States)

    Hasan, Mohammad; Mandal, Bhabani Prasad

    2018-02-01

    We calculate the time taken by a wave packet to travel through a classically forbidden region of space in space fractional quantum mechanics. We obtain the close form expression of tunneling time from a rectangular barrier by stationary phase method. We show that tunneling time depends upon the width b of the barrier for b → ∞ and therefore Hartman effect doesn't exist in space fractional quantum mechanics. Interestingly we found that the tunneling time monotonically reduces with increasing b. The tunneling time is smaller in space fractional quantum mechanics as compared to the case of standard quantum mechanics. We recover the Hartman effect of standard quantum mechanics as a special case of space fractional quantum mechanics.

  11. Time-Varying Transition Probability Matrix Estimation and Its Application to Brand Share Analysis.

    Science.gov (United States)

    Chiba, Tomoaki; Hino, Hideitsu; Akaho, Shotaro; Murata, Noboru

    2017-01-01

    In a product market or stock market, different products or stocks compete for the same consumers or purchasers. We propose a method to estimate the time-varying transition matrix of the product share using a multivariate time series of the product share. The method is based on the assumption that each of the observed time series of shares is a stationary distribution of the underlying Markov processes characterized by transition probability matrices. We estimate transition probability matrices for every observation under natural assumptions. We demonstrate, on a real-world dataset of the share of automobiles, that the proposed method can find intrinsic transition of shares. The resulting transition matrices reveal interesting phenomena, for example, the change in flows between TOYOTA group and GM group for the fiscal year where TOYOTA group's sales beat GM's sales, which is a reasonable scenario.

  12. Time-Varying Transition Probability Matrix Estimation and Its Application to Brand Share Analysis.

    Directory of Open Access Journals (Sweden)

    Tomoaki Chiba

    Full Text Available In a product market or stock market, different products or stocks compete for the same consumers or purchasers. We propose a method to estimate the time-varying transition matrix of the product share using a multivariate time series of the product share. The method is based on the assumption that each of the observed time series of shares is a stationary distribution of the underlying Markov processes characterized by transition probability matrices. We estimate transition probability matrices for every observation under natural assumptions. We demonstrate, on a real-world dataset of the share of automobiles, that the proposed method can find intrinsic transition of shares. The resulting transition matrices reveal interesting phenomena, for example, the change in flows between TOYOTA group and GM group for the fiscal year where TOYOTA group's sales beat GM's sales, which is a reasonable scenario.

  13. Exploring the Cognitive Foundations of the Shared Attention Mechanism: Evidence for a Relationship between Self-Categorization and Shared Attention across the Autism Spectrum

    Science.gov (United States)

    Skorich, Daniel P.; Gash, Tahlia B.; Stalker, Katie L.; Zheng, Lidan; Haslam, S. Alexander

    2017-01-01

    The social difficulties of autism spectrum disorder (ASD) are typically explained as a disruption in the Shared Attention Mechanism (SAM) sub-component of the theory of mind (ToM) system. In the current paper, we explore the hypothesis that SAM's capacity to construct the self-other-object relations necessary for shared-attention arises from a…

  14. Children's Perspectives on Everyday Experiences of Shared Residence: Time, Emotions and Agency Dilemmas

    Science.gov (United States)

    Haugen, Gry Mette D.

    2010-01-01

    Shared residence is often presented as an arrangement that is in the best interests of the child following the divorce of its parents. Based on in-depth interviews with Norwegian children who have experienced shared residence, this article seeks to explore some dilemmas concerning time, agency and the children's emotions. Three characteristics of…

  15. A new revenue sharing mechanism for coordinating multi-echelon supply chains

    NARCIS (Netherlands)

    Rhee, van der B.; Venugopal, V.; Veen, van der J.A.A.; Nalla, V.R.

    2009-01-01

    One of the key issues in Supply Chain Management is to prevent sub-optimization caused by the distribution of decision power over the various entities. Over the last decade, various contract mechanisms such as Revenue Sharing (RS) have been used to overcome such difficulties. Typically, a contract

  16. Part-time and Job-Share Careers Among Pharmacy Practice Faculty Members

    OpenAIRE

    Griffin, Brooke; Vest, Kathleen; Pohl, Shaunte; Mazan, Jennifer; Winkler, Susan

    2014-01-01

    Part-time and job-share policies may allow pharmacy practice faculty members to achieve work/life balance while pursuing their professional goals. Precedent for alternative work schedules within the health professions community can be found throughout the literature; however, little is known about part-time roles in academic pharmacy. The design and implementation of 3 different alternative faculty appointments are described and department chair and faculty perspectives are shared. Teaching, ...

  17. A STUDY OF SOME SOFTWARE PARAMETERS IN TIME-SHARING SYSTEMS.

    Science.gov (United States)

    A review is made of some existing time-sharing computer systems and an exploration of various software characteristics is conducted. This...of the various parameters upon the average response cycle time, the average number in the queue awaiting service , the average length of time a user is

  18. Intelligence and temporal accuracy of behaviour: unique and shared associations with reaction time and motor timing.

    Science.gov (United States)

    Holm, Linus; Ullén, Fredrik; Madison, Guy

    2011-10-01

    Intelligence is associated with accuracy in a wide range of timing tasks. One source of such associations is likely to be individual differences in top-down control, e.g., sustained attention, that influence performance in both temporal tasks and other cognitively controlled behaviours. In addition, we have studied relations between intelligence and a simple rhythmic motor task, isochronous serial interval production (ISIP), and found a substantial component of that relation, which is independent of fluctuations in top-down control. The main purpose of the present study was to investigate whether such bottom-up mechanisms are involved also in the relation between intelligence and reaction time (RT) tasks. We thus investigated whether common variance between the ISIP and RT tasks underlies their respective associations with intelligence. Two hundred and twelve participants performed a simple RT task, a choice RT task and the ISIP task. Intelligence was assessed with the Raven SPM Plus. The analysed timing variables included mean and variability in the RT tasks and two variance components in the ISIP task. As predicted, RT and ISIP variables were associated with intelligence. The timing variables were positively intercorrelated, and a principal component analysis revealed a substantial first principal component that was strongly related to all timing variables, and positively correlated with intelligence. Furthermore, a commonality analysis demonstrated that the relations between intelligence and the timing variables involved a commonality between the timing variables as well as unique contributions from choice RT and ISIP. We discuss possible implications of these findings and argue that they support our main hypothesis, i.e., that relations between intelligence and RT tasks have a bottom-up component.

  19. Information Sharing Mechanism among Mobile Agents In Ad-hoc Network Environment and Its Applications

    Directory of Open Access Journals (Sweden)

    Kunio Umetsuji

    2004-12-01

    Full Text Available Mobile agents are programs that can move from one site to another in a network with their data and states. Mobile agents are expected to be an essential tool in pervasive computing. In multi platform environment, it is important to communicate with mobile agents only using their universal or logical name not using their physical locations. More, in an ad-hoc network environment, an agent can migrate autonomously and communicate with other agents on demand. It is difficult that mobile agent grasps the position information on other agents correctly each other, because mobile agent processes a task while moving a network successively. In order to realize on-demand mutual communication among mobile agents without any centralized servers, we propose a new information sharing mechanism within mobile agents. In this paper, we present a new information sharing mechanism within mobile agents. The method is a complete peer based and requires no agent servers to manage mobile agent locations. Therefore, a mobile agent can get another mobile agent, communicate with it and shares information stored in the agent without any knowledge of the location of the target mobile agent. The basic idea of the mechanism is an introduction of Agent Ring, Agent Chain and Shadow Agent. With this mechanism, each agent can communicate with other agents in a server-less environment, which is suitable for ad-hoc agent network and an agent system can manage agents search and communications efficiently.

  20. Incentive Mechanism for P2P Content Sharing over Heterogenous Access Networks

    Science.gov (United States)

    Sato, Kenichiro; Hashimoto, Ryo; Yoshino, Makoto; Shinkuma, Ryoichi; Takahashi, Tatsuro

    In peer-to-peer (P2P) content sharing, users can share their content by contributing their own resources to one another. However, since there is no incentive for contributing contents or resources to others, users may attempt to obtain content without any contribution. To motivate users to contribute their resources to the service, incentive-rewarding mechanisms have been proposed. On the other hand, emerging wireless technologies, such as IEEE 802.11 wireless local area networks, beyond third generation (B3G) cellular networks and mobile WiMAX, provide high-speed Internet access for wireless users. Using these high-speed wireless access, wireless users can use P2P services and share their content with other wireless users and with fixed users. However, this diversification of access networks makes it difficult to appropriately assign rewards to each user according to their contributions. This is because the cost necessary for contribution is different in different access networks. In this paper, we propose a novel incentive-rewarding mechanism called EMOTIVER that can assign rewards to users appropriately. The proposed mechanism uses an external evaluator and interactive learning agents. We also investigate a way of appropriately controlling rewards based on the system service's quality and managing policy.

  1. Shared molecular and cellular mechanisms of premature ageing and ageing-associated diseases.

    Science.gov (United States)

    Kubben, Nard; Misteli, Tom

    2017-10-01

    Ageing is the predominant risk factor for many common diseases. Human premature ageing diseases are powerful model systems to identify and characterize cellular mechanisms that underpin physiological ageing. Their study also leads to a better understanding of the causes, drivers and potential therapeutic strategies of common diseases associated with ageing, including neurological disorders, diabetes, cardiovascular diseases and cancer. Using the rare premature ageing disorder Hutchinson-Gilford progeria syndrome as a paradigm, we discuss here the shared mechanisms between premature ageing and ageing-associated diseases, including defects in genetic, epigenetic and metabolic pathways; mitochondrial and protein homeostasis; cell cycle; and stem cell-regenerative capacity.

  2. Sojourn time asymptotics in Processor Sharing queues with varying service rate

    NARCIS (Netherlands)

    Egorova, R.; Mandjes, M.R.H.; Zwart, B.

    2007-01-01

    Abstract This paper addresses the sojourn time asymptotics for a GI/GI/⋅ queue operating under the Processor Sharing (PS) discipline with stochastically varying service rate. Our focus is on the logarithmic estimates of the tail of sojourn-time distribution, under the assumption that the job-size

  3. Sojourn time asymptotics in the M/G/1 processor sharing queue

    NARCIS (Netherlands)

    A.P. Zwart (Bert); O.J. Boxma (Onno)

    1998-01-01

    textabstractWe show for the M/G/1 processor sharing queue that the service time distribution is regularly varying of index $-nu$, $nu$ non-integer, iff the sojourn time distribution is regularly varying of index $-nu $. This result is derived from a new expression for the Laplace-Stieltjes transform

  4. Time perception mechanisms at central nervous system

    Directory of Open Access Journals (Sweden)

    Rhailana Fontes

    2016-04-01

    Full Text Available The five senses have specific ways to receive environmental information and lead to central nervous system. The perception of time is the sum of stimuli associated with cognitive processes and environmental changes. Thus, the perception of time requires a complex neural mechanism and may be changed by emotional state, level of attention, memory and diseases. Despite this knowledge, the neural mechanisms of time perception are not yet fully understood. The objective is to relate the mechanisms involved the neurofunctional aspects, theories, executive functions and pathologies that contribute the understanding of temporal perception. Articles form 1980 to 2015 were searched by using the key themes: neuroanatomy, neurophysiology, theories, time cells, memory, schizophrenia, depression, attention-deficit hyperactivity disorder and Parkinson’s disease combined with the term perception of time. We evaluated 158 articles within the inclusion criteria for the purpose of the study. We conclude that research about the holdings of the frontal cortex, parietal, basal ganglia, cerebellum and hippocampus have provided advances in the understanding of the regions related to the perception of time. In neurological and psychiatric disorders, the understanding of time depends on the severity of the diseases and the type of tasks.

  5. Time Perception Mechanisms at Central Nervous System.

    Science.gov (United States)

    Fontes, Rhailana; Ribeiro, Jéssica; Gupta, Daya S; Machado, Dionis; Lopes-Júnior, Fernando; Magalhães, Francisco; Bastos, Victor Hugo; Rocha, Kaline; Marinho, Victor; Lima, Gildário; Velasques, Bruna; Ribeiro, Pedro; Orsini, Marco; Pessoa, Bruno; Leite, Marco Antonio Araujo; Teixeira, Silmar

    2016-04-01

    The five senses have specific ways to receive environmental information and lead to central nervous system. The perception of time is the sum of stimuli associated with cognitive processes and environmental changes. Thus, the perception of time requires a complex neural mechanism and may be changed by emotional state, level of attention, memory and diseases. Despite this knowledge, the neural mechanisms of time perception are not yet fully understood. The objective is to relate the mechanisms involved the neurofunctional aspects, theories, executive functions and pathologies that contribute the understanding of temporal perception. Articles form 1980 to 2015 were searched by using the key themes: neuroanatomy, neurophysiology, theories, time cells, memory, schizophrenia, depression, attention-deficit hyperactivity disorder and Parkinson's disease combined with the term perception of time. We evaluated 158 articles within the inclusion criteria for the purpose of the study. We conclude that research about the holdings of the frontal cortex, parietal, basal ganglia, cerebellum and hippocampus have provided advances in the understanding of the regions related to the perception of time. In neurological and psychiatric disorders, the understanding of time depends on the severity of the diseases and the type of tasks.

  6. Information-sharing tendency on Twitter and time evolution of tweeting

    Science.gov (United States)

    Kwon, H. W.; Kim, H. S.; Lee, K.; Choi, M. Y.

    2013-03-01

    While topics on Twitter may be categorized according to their predictability and sustainability, some topics have characteristics depending on the time scale. Here we propose a good measure for the transition of sustainability, which we call the information-sharing tendency, and find that the unpredictability on Twitter is provoked by the exposure of Twitter users to external environments, e.g., mass media and other social network services. In addition, it is demonstrated that the numbers of articles and comments on on-line newspapers serve as plausible measures of exposure. From such measures of exposure, the time evolution of tweeting can be described, when the information-sharing tendency is known.

  7. Shared use agreements and leisure time physical activity in North Carolina public schools.

    Science.gov (United States)

    Carlton, Troy A; Kanters, Michael A; Bocarro, Jason N; Floyd, Myron F; Edwards, Michael B; Suau, Luis J

    2017-02-01

    Although increasing community access to public schools through shared use agreements (SUAs) has been a recommended strategy for promoting physical activity (PA) among national, state and local organizations, empirical evidence examining the efficacy of SUAs is limited. This study examined the degree of usage and production of PA among schools with shared use, and how variation in PA output is related to characteristics of the school, type of activity, facility type, and when activity occurs. Data were collected in 20 schools across North Carolina using System for Observing Play and Recreation in Communities (SOPARC) and Structured Physical Activity Surveys (SPAS) to assess PA in school athletic facilities during out of school time. Findings indicated that although schools had a policy of shared or open use, most facilities were empty during non-school hours. Hierarchal linear regression models also showed that formal programming was positively associated with both use and PA levels. Given the abundance of empty facilities, community groups in need of space to facilitate structured PA programs should pursue avenues of sharing facilities with public schools. Furthermore, to increase the efficacy of shared use, structured physical activity programs may be needed. Future studies are encouraged to further explore the effects of the specific types of shared use programs on PA production as well other aspects of the built environment surrounding schools. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Exploring the Cognitive Foundations of the Shared Attention Mechanism: Evidence for a Relationship Between Self-Categorization and Shared Attention Across the Autism Spectrum.

    Science.gov (United States)

    Skorich, Daniel P; Gash, Tahlia B; Stalker, Katie L; Zheng, Lidan; Haslam, S Alexander

    2017-05-01

    The social difficulties of autism spectrum disorder (ASD) are typically explained as a disruption in the Shared Attention Mechanism (SAM) sub-component of the theory of mind (ToM) system. In the current paper, we explore the hypothesis that SAM's capacity to construct the self-other-object relations necessary for shared-attention arises from a self-categorization process, which is weaker among those with more autistic-like traits. We present participants with self-categorization and shared-attention tasks, and measure their autism-spectrum quotient (AQ). Results reveal a negative relationship between AQ and shared-attention, via self-categorization, suggesting a role for self-categorization in the disruption in SAM seen in ASD. Implications for intervention, and for a ToM model in which weak central coherence plays a role are discussed.

  9. It's all in the timing: calibrating temporal penalties for biomedical data sharing.

    Science.gov (United States)

    Xia, Weiyi; Wan, Zhiyu; Yin, Zhijun; Gaupp, James; Liu, Yongtai; Clayton, Ellen Wright; Kantarcioglu, Murat; Vorobeychik, Yevgeniy; Malin, Bradley A

    2018-01-01

    Biomedical science is driven by datasets that are being accumulated at an unprecedented rate, with ever-growing volume and richness. There are various initiatives to make these datasets more widely available to recipients who sign Data Use Certificate agreements, whereby penalties are levied for violations. A particularly popular penalty is the temporary revocation, often for several months, of the recipient's data usage rights. This policy is based on the assumption that the value of biomedical research data depreciates significantly over time; however, no studies have been performed to substantiate this belief. This study investigates whether this assumption holds true and the data science policy implications. This study tests the hypothesis that the value of data for scientific investigators, in terms of the impact of the publications based on the data, decreases over time. The hypothesis is tested formally through a mixed linear effects model using approximately 1200 publications between 2007 and 2013 that used datasets from the Database of Genotypes and Phenotypes, a data-sharing initiative of the National Institutes of Health. The analysis shows that the impact factors for publications based on Database of Genotypes and Phenotypes datasets depreciate in a statistically significant manner. However, we further discover that the depreciation rate is slow, only ∼10% per year, on average. The enduring value of data for subsequent studies implies that revoking usage for short periods of time may not sufficiently deter those who would violate Data Use Certificate agreements and that alternative penalty mechanisms may need to be invoked. © The Author 2017. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  10. Extending a HSF-enabled open-source real-time operating system with resource sharing

    NARCIS (Netherlands)

    Heuvel, van den M.M.H.P.; Bril, R.J.; Lukkien, J.J.; Behnam, M.; Petters, S.M.; Zijlstra, P.

    2010-01-01

    Hierarchical scheduling frameworks (HSFs) provide means for composing complex real-time systems from well-defined, independently analyzed subsystems. To support resource sharing within two-level, fixed priority scheduled HSFs, two synchronization protocols based on the stack resource policy (SRP)

  11. Working Memory Span Development: A Time-Based Resource-Sharing Model Account

    Science.gov (United States)

    Barrouillet, Pierre; Gavens, Nathalie; Vergauwe, Evie; Gaillard, Vinciane; Camos, Valerie

    2009-01-01

    The time-based resource-sharing model (P. Barrouillet, S. Bernardin, & V. Camos, 2004) assumes that during complex working memory span tasks, attention is frequently and surreptitiously switched from processing to reactivate decaying memory traces before their complete loss. Three experiments involving children from 5 to 14 years of age…

  12. Mean sojourn times for phase-type discriminatory processor sharing systems

    NARCIS (Netherlands)

    Haviv, M.; van der Wal, J.

    2008-01-01

    In a discriminatory processor sharing (DPS) queueing model, each job (or customer) belongs to one out of finitely many classes. The arrival processes are Poisson. Classes differ with respect to arrival rates and service time distributions. Moreover, classes have different priority levels. All jobs

  13. Protocol-transparent resource sharing in hierarchically scheduled real-time systems

    NARCIS (Netherlands)

    Heuvel, van den M.M.H.P.; Bril, R.J.; Lukkien, J.J.

    2010-01-01

    Hierarchical scheduling frameworks (HSFs) provide means for composing complex real-time systems from well-defined, independently analyzed subsystems. To support resource sharing within two-level HSFs, three synchronization protocols based on the stack resource policy (SRP) have recently been

  14. Sharing Time and the Poetic Patterning of Caribbean Independence: The Narrative Architecture of Voice

    Science.gov (United States)

    Van der Aa, Jef

    2013-01-01

    This article discusses the narrative architecture and interactional uptake of a school child's story about independence in Barbados during sharing time. It is found that an institutional focus on standard resources impacts both teachers' and children's sociolinguistic behavior. Ethnopoetic analysis brings out the child's patterned use of narrative…

  15. Shared random access memory resource for multiprocessor real-time systems

    International Nuclear Information System (INIS)

    Dimmler, D.G.; Hardy, W.H. II

    1977-01-01

    A shared random-access memory resource is described which is used within real-time data acquisition and control systems with multiprocessor and multibus organizations. Hardware and software aspects are discussed in a specific example where interconnections are done via a UNIBUS. The general applicability of the approach is also discussed

  16. The interplay of couple's shared time, women's intimacy, and intradyadic stress.

    Science.gov (United States)

    Milek, Anne; Butler, Emily A; Bodenmann, Guy

    2015-12-01

    Theoretically, spending time together should be central for couples to build intimacy and should be associated with less relationship stress; however, few empirical studies have examined these links. The present study used 14 days of diary data from 92 women to investigate the interplay between the amount of time they spent with their partner (shared time), intimacy, and daily stress originating inside the relationship (intradyadic stress) on a within- and between-personal level. Multilevel analyses revealed moderation patterns: For example, when women spent more time with their partners than usual on a weekday with low levels of intradyadic stress, they reported higher intimacy. These associations varied substantially between women and were weaker on the weekend or on days with high levels of intradyadic stress. At the between-person level, higher average shared time appeared to buffer the negative association between intradyadic stress and intimacy. Our results suggest that daily fluctuations in intradyadic stress, intimacy, and shared time may have different implications compared with aggregated amounts of those variables. Spending more time together on a weekday with low intimacy might be linked to more intradyadic stress, but aggregated over the long run, spending more time together may provide opportunities for stress resolution and help couples to maintain their intimacy. (c) 2015 APA, all rights reserved).

  17. Time Operator in Relativistic Quantum Mechanics

    Science.gov (United States)

    Khorasani, Sina

    2017-07-01

    It is first shown that the Dirac’s equation in a relativistic frame could be modified to allow discrete time, in agreement to a recently published upper bound. Next, an exact self-adjoint 4 × 4 relativistic time operator for spin-1/2 particles is found and the time eigenstates for the non-relativistic case are obtained and discussed. Results confirm the quantum mechanical speculation that particles can indeed occupy negative energy levels with vanishingly small but non-zero probablity, contrary to the general expectation from classical physics. Hence, Wolfgang Pauli’s objection regarding the existence of a self-adjoint time operator is fully resolved. It is shown that using the time operator, a bosonic field referred here to as energons may be created, whose number state representations in non-relativistic momentum space can be explicitly found.

  18. A Supply Chain Coordination Mechanism with Cost Sharing of Corporate Social Responsibility

    Directory of Open Access Journals (Sweden)

    Yong Liu

    2018-04-01

    Full Text Available The competition of modern enterprises has shifted from brand competition among enterprises of the past to that of supply chains; and considering corporate social responsibility (CSR within supply chain management has become an inevitable requirement for improving the competitiveness of enterprises and conforms to the trend of standardization of social responsibility guidelines. This paper deals with channel coordination and decision-making in a CSR supply chain that is comprised of a dominant retailer and n homogeneous suppliers. The Stackelberg game is employed to analyze the optimal decision-making of this supply chain under either decentralized or centralized decision-making processes. After that, the thought and method of super conflict equilibrium are used to design the coordination decision-making mechanism of this supply chain based on the cost sharing of CSR to solve channel conflict and to optimize the decision. The results show that the proposed mechanism based on the cost sharing of CSR is better than those with only either the retailer or the suppliers being CSR; and it can well describe the relationship between the retailer and the suppliers, and increase the eagerness of the retailer and suppliers to carry out their CSR under various circumstances without having the profits adversely affected. As a matter of fact, this mechanism maximizes the profits of the entire supply chain system and also enhances the competitiveness of the chain.

  19. Shared control on lunar spacecraft teleoperation rendezvous operations with large time delay

    Science.gov (United States)

    Ya-kun, Zhang; Hai-yang, Li; Rui-xue, Huang; Jiang-hui, Liu

    2017-08-01

    Teleoperation could be used in space on-orbit serving missions, such as object deorbits, spacecraft approaches, and automatic rendezvous and docking back-up systems. Teleoperation rendezvous and docking in lunar orbit may encounter bottlenecks for the inherent time delay in the communication link and the limited measurement accuracy of sensors. Moreover, human intervention is unsuitable in view of the partial communication coverage problem. To solve these problems, a shared control strategy for teleoperation rendezvous and docking is detailed. The control authority in lunar orbital maneuvers that involves two spacecraft as rendezvous and docking in the final phase was discussed in this paper. The predictive display model based on the relative dynamic equations is established to overcome the influence of the large time delay in communication link. We discuss and attempt to prove via consistent, ground-based simulations the relative merits of fully autonomous control mode (i.e., onboard computer-based), fully manual control (i.e., human-driven at the ground station) and shared control mode. The simulation experiments were conducted on the nine-degrees-of-freedom teleoperation rendezvous and docking simulation platform. Simulation results indicated that the shared control methods can overcome the influence of time delay effects. In addition, the docking success probability of shared control method was enhanced compared with automatic and manual modes.

  20. Action simulation: time course and representational mechanisms

    Science.gov (United States)

    Springer, Anne; Parkinson, Jim; Prinz, Wolfgang

    2013-01-01

    The notion of action simulation refers to the ability to re-enact foreign actions (i.e., actions observed in other individuals). Simulating others' actions implies a mirroring of their activities, based on one's own sensorimotor competencies. Here, we discuss theoretical and experimental approaches to action simulation and the study of its representational underpinnings. One focus of our discussion is on the timing of internal simulation and its relation to the timing of external action, and a paradigm that requires participants to predict the future course of actions that are temporarily occluded from view. We address transitions between perceptual mechanisms (referring to action representation before and after occlusion) and simulation mechanisms (referring to action representation during occlusion). Findings suggest that action simulation runs in real-time; acting on newly created action representations rather than relying on continuous visual extrapolations. A further focus of our discussion pertains to the functional characteristics of the mechanisms involved in predicting other people's actions. We propose that two processes are engaged, dynamic updating and static matching, which may draw on both semantic and motor information. In a concluding section, we discuss these findings in the context of broader theoretical issues related to action and event representation, arguing that a detailed functional analysis of action simulation in cognitive, neural, and computational terms may help to further advance our understanding of action cognition and motor control. PMID:23847563

  1. Abundant genetic overlap between blood lipids and immune-mediated diseases indicates shared molecular genetic mechanisms.

    Directory of Open Access Journals (Sweden)

    Ole A Andreassen

    Full Text Available Epidemiological studies suggest a relationship between blood lipids and immune-mediated diseases, but the nature of these associations is not well understood. We used genome-wide association studies (GWAS to investigate shared single nucleotide polymorphisms (SNPs between blood lipids and immune-mediated diseases. We analyzed data from GWAS (n~200,000 individuals, applying new False Discovery Rate (FDR methods, to investigate genetic overlap between blood lipid levels [triglycerides (TG, low density lipoproteins (LDL, high density lipoproteins (HDL] and a selection of archetypal immune-mediated diseases (Crohn's disease, ulcerative colitis, rheumatoid arthritis, type 1 diabetes, celiac disease, psoriasis and sarcoidosis. We found significant polygenic pleiotropy between the blood lipids and all the investigated immune-mediated diseases. We discovered several shared risk loci between the immune-mediated diseases and TG (n = 88, LDL (n = 87 and HDL (n = 52. Three-way analyses differentiated the pattern of pleiotropy among the immune-mediated diseases. The new pleiotropic loci increased the number of functional gene network nodes representing blood lipid loci by 40%. Pathway analyses implicated several novel shared mechanisms for immune pathogenesis and lipid biology, including glycosphingolipid synthesis (e.g. FUT2 and intestinal host-microbe interactions (e.g. ATG16L1. We demonstrate a shared genetic basis for blood lipids and immune-mediated diseases independent of environmental factors. Our findings provide novel mechanistic insights into dyslipidemia and immune-mediated diseases and may have implications for therapeutic trials involving lipid-lowering and anti-inflammatory agents.

  2. A supply chain contract with flexibility as a risk-sharing mechanism for demand forecasting

    Science.gov (United States)

    Kim, Whan-Seon

    2013-06-01

    Demand forecasting is one of the main causes of the bullwhip effect in a supply chain. As a countermeasure for demand uncertainty as well as a risk-sharing mechanism for demand forecasting in a supply chain, this article studies a bilateral contract with order quantity flexibility. Under the contract, the buyer places orders in advance for the predetermined horizons and makes minimum purchase commitments. The supplier, in return, provides the buyer with the flexibility to adjust the order quantities later, according to the most updated demand information. To conduct comparative simulations, four-echelon supply chain models, that employ the contracts and different forecasting techniques under dynamic market demands, are developed. The simulation outcomes show that demand fluctuation can be effectively absorbed by the contract scheme, which enables better inventory management and customer service. Furthermore, it has been verified that the contract scheme under study plays a role as an effective coordination mechanism in a decentralised supply chain.

  3. Shared and unique mechanisms underlying binge eating disorder and addictive disorders

    Science.gov (United States)

    Schulte, Erica M.; Grilo, Carlos M.; Gearhardt, Ashley N.

    2018-01-01

    Scientific interest in “food addiction” is growing, but the topic remains controversial. One critique of “food addiction” is its high degree of phenotypic overlap with binge eating disorder (BED). In order to examine associations between problematic eating behaviors, such as binge eating and “food addiction,” we propose the need to move past examining similarities and differences in symptomology. Instead, focusing on relevant mechanisms may more effectively determine whether “food addiction” contributes to disordered eating behavior for some individuals. This paper reviews the evidence for mechanisms that are shared (i.e., reward dysfunction, impulsivity) and unique for addiction (i.e., withdrawal, tolerance) and eating disorder (i.e., dietary restraint, shape/weight concern) frameworks. This review will provide a guiding framework to outline future areas of research needed to evaluate the validity of the “food addiction” model and to understand its potential contribution to disordered eating. PMID:26879210

  4. Infectivity versus Seeding in Neurodegenerative Diseases Sharing a Prion-Like Mechanism

    Directory of Open Access Journals (Sweden)

    Natalia Fernández-Borges

    2013-01-01

    Full Text Available Prions are considered the best example to prove that the biological information can be transferred protein to protein through a conformational change. The term “prion-like” is used to describe molecular mechanisms that share similarities with the mammalian prion protein self-perpetuating aggregation and spreading characteristics. Since prions are presumably composed only of protein and are infectious, the more similar the mechanisms that occur in the different neurodegenerative diseases, the more these processes will resemble an infection. In vitro and in vivo experiments carried out during the last decade in different neurodegenerative disorders such as Alzheimer's disease (AD, Parkinson's diseases (PD, and amyotrophic lateral sclerosis (ALS have shown a convergence toward a unique mechanism of misfolded protein propagation. In spite of the term “infection” that could be used to explain the mechanism governing the diversity of the pathological processes, other concepts as “seeding” or “de novo induction” are being used to describe the in vivo propagation and transmissibility of misfolded proteins. The current studies are demanding an extended definition of “disease-causing agents” to include those already accepted as well as other misfolded proteins. In this new scenario, “seeding” would be a type of mechanism by which an infectious agent can be transmitted but should not be used to define a whole “infection” process.

  5. [Part-time medical specialist training; experiences with job-sharing for trainee internists].

    Science.gov (United States)

    Bevers, K; Nauta, S; Stuyt, P M

    2004-02-14

    Due to various factors such as social changes, an increasing number of couples with two incomes, and a growing proportion of female doctors, there has been a growing demand for part-time work in recent years. This is also true for resident physicians. Objections such as a discontinuity in care and the decline in the quality of education frequently prevent resident physicians from working part-time. Over the past two years, the University Medical Centre Nijmegen, the Netherlands, has experimented with job-sharing on clinical wards for resident physicians in internal medicine. This approach works well in practice, as long as a number of conditions, including the proper transfer of medical information and good communication, are satisfied. Job-sharing is one means of satisfying the growing demand for part-time work among resident physicians and specialists.

  6. Quantum mechanics, stochasticity and space-time

    International Nuclear Information System (INIS)

    Ramanathan, R.

    1986-04-01

    An extended and more rigorous version of a recent proposal for an objective stochastic formulation of quantum mechanics along with its extension to the relativistic case without spin is presented. The relativistic Klein-Gordon equation is shown to be a particular form of the relativistic Kolmogorov-Fokker-Planck equation which is derived from a covariant formulation of the Chapman-Kolmogorov condition. Complexification of probability amplitudes is again achieved only through a conformal rotation of Minkowski space-time M 4 . (author)

  7. Part-time and job-share careers among pharmacy practice faculty members.

    Science.gov (United States)

    Griffin, Brooke; Vest, Kathleen; Pohl, Shaunte; Mazan, Jennifer; Winkler, Susan

    2014-04-17

    Part-time and job-share policies may allow pharmacy practice faculty members to achieve work/life balance while pursuing their professional goals. Precedent for alternative work schedules within the health professions community can be found throughout the literature; however, little is known about part-time roles in academic pharmacy. The design and implementation of 3 different alternative faculty appointments are described and department chair and faculty perspectives are shared. Teaching, service, and scholarship responsibilities, as well as outcomes before and after changes in appointment, are described. Advantages and disadvantages, including advice for other colleges of pharmacy, are presented. Alternate appointments may be a key factor in retaining highly qualified faculty members who continue to bring their expertise to teaching, precepting, and scholarship within a college or school of pharmacy.

  8. Research on Information Sharing Mechanism of Network Organization Based on Evolutionary Game

    Science.gov (United States)

    Wang, Lin; Liu, Gaozhi

    2018-02-01

    This article first elaborates the concept and effect of network organization, and the ability to share information is analyzed, secondly introduces the evolutionary game theory, network organization for information sharing all kinds of limitations, establishes the evolutionary game model, analyzes the dynamic evolution of network organization of information sharing, through reasoning and evolution. The network information sharing by the initial state and two sides of the game payoff matrix of excess profits and information is the information sharing of cost and risk sharing are the influence of network organization node information sharing decision.

  9. The Effects of Abandonment Options on Investment Timing and Profit Sharing of FDI

    Directory of Open Access Journals (Sweden)

    Weiwei Zhang

    2017-01-01

    Full Text Available The paper incorporates cooperative game theory into a real option method in a foreign direct investment setting and examines the operational decisions of a multinational corporation in a cooperative framework, where the corporation is endowed with an abandonment option and shares its profit with the host country. In particular, we investigate how the abandonment options affect the optimal investment timing and the optimal profit share of a foreign direct investment using a real option game method. We show that the flexibility of the abandonment option induces the corporation to investment earlier, which indicates the negative effects on investment trigger. The result is consistent with intuition since the abandonment option provides insurance and thus reduces the overall risk of the project. We also find that the introduction of the abandonment option reduces the optimal profit share in a cooperative framework and in turn the lower profit share increases the investment trigger, thereby having a positive effect on the investment threshold to hinder the investment. By numerical analysis, we find that the overall effect of the abandonment options is inversely related to the investment trigger. These findings provide quantitative analysis about the decisions regarding cooperation in international investment extraction projects.

  10. Psychological reality and the role of the teacher in early-education sharing time

    Science.gov (United States)

    Alsafi, Abdullah T.

    1994-01-01

    The study of children's language development has been strongly influenced since the 1950s by linguistic research. How well, however, has the education of young children incorporated the concept of psychological reality, which interrelates the child's perceptual and cognitive development with linguistic and non-linguistic events in his/her environment? In reply to this question, the paper concentrates on"sharing time", known also as"show and tell", which has both affective and cognitive value. Although sharing time is a student-centered activity, the teacher plays a pivotal role in establishing its context, structure and norms. Feedback from the teacher and peers promotes language development, and the growth of curiosity and inquisitiveness. The article is derived from experience in teaching kindergarten teachers to conduct sharing time periods in Saudi Arabia. Practical suggestions are made for the implementation of the activity, in the interests of encouraging spontaneous and personalized language rather than focusing on evaluation of students' competence in the formal aspects of language development.

  11. Optimal loading and protection of multi-state systems considering performance sharing mechanism

    International Nuclear Information System (INIS)

    Xiao, Hui; Shi, Daimin; Ding, Yi; Peng, Rui

    2016-01-01

    Engineering systems are designed to carry the load. The performance of the system largely depends on how much load it carries. On the other hand, the failure rate of the system is strongly affected by its load. Besides internal failures, such as fatigue and aging process, systems may also fail due to external impacts such as nature disasters and terrorism. In this paper, we integrate the effect of loading and protection of external impacts on multi-state systems with performance sharing mechanism. The objective of this research is to determine how to balance the load and protection on system elements. An availability evaluation algorithm of the proposed system is suggested and the corresponding optimization problem is solved utilizing genetic algorithms. - Highlights: • Performance sharing of multi-state systems is considered. • The effect of load on system elements is analyzed. • Joint optimization model of element loading and protection is formulated. • Genetic Algorithms are adapted to solve the reliability optimization problem.

  12. Time-resolved echo-shared parallel MRA of the lung: observer preference study of image quality in comparison with non-echo-shared sequences

    International Nuclear Information System (INIS)

    Fink, C.; Puderbach, M.; Zaporozhan, J.; Plathow, C.; Kauczor, H.-U.; Ley, S.

    2005-01-01

    The aim of this study was to evaluate the image quality of time-resolved echo-shared parallel MRA of the lung. The pulmonary vasculature of nine patients (seven females, two males; median age: 44 years) with pulmonary disease was examined using a time-resolved MRA sequence combining echo sharing with parallel imaging (time-resolved echo-shared angiography technique, or TREAT). The sharpness of the vessel borders, conspicuousness of peripheral lung vessels, artifact level, and overall image quality of TREAT was assessed independently by four readers in a side-by-side comparison with non-echo-shared time-resolved parallel MRA data (pMRA) previously acquired in the same patients. Furthermore, the SNR of pulmonary arteries (PA) and veins (PV) achieved with both pulse sequences was compared. The mean voxel size of TREAT MRA was decreased by 24% compared with the non-echo-shared MRA. Regarding the sharpness of the vessel borders, conspicuousness of peripheral lung vessels, and overall image quality the TREAT sequence was rated superior in 75-76% of all cases. If the TREAT images were preferred over the pMRA images, the advantage was rated as major in 61-71% of all cases. The level of artifacts was not increased with the TREAT sequence. The mean interobserver agreement for all categories ranged between fair (artifact level) and good (overall image quality). The maximum SNR of TREAT did not differ from non-echo-shared parallel MRA (PA: TREAT: 273±45; pMRA: 280±71; PV: TREAT: 273±33; pMRA: 258±62). TREAT achieves a higher spatial resolution than non-echo-shared parallel MRA which is also perceived as an improved image quality. (orig.)

  13. Physician as partner or salesman? Shared decision-making in real-time encounters.

    Science.gov (United States)

    Karnieli-Miller, Orit; Eisikovits, Zvi

    2009-07-01

    The results of recent research have led to the increased advocacy of shared decision-making regarding medical treatment. Nonetheless, only a limited number of studies have focused on the process of decision-making in real-time encounters. The present paper aims to document and analyze this process. Specifically, we assess whether these decisions are the result of partnership or of persuasive tactics based on power and hierarchical relationships. We will describe and analyze different strategies used by pediatric gastroenterologists in breaking bad news encounters, as well as their consequences. The analysis is based on a multi-method, multi-participant phenomenological study on breaking bad news to adolescents and their families regarding a chronic illness. It included 17 units of analysis (actual encounters and 52 interviews with physicians, parents and adolescents). Data were collected from three hospitals in Northern Israel using observations and audiotapes of diagnosis disclosure encounters and audio-taped interviews with all participants. The analysis identified eight different presentation tactics used in actual encounters during which physicians made various use of language, syntax and different sources of power to persuade patients to agree with their preferred treatment choice. The tactics included various ways of presenting the illness, treatment and side effects; providing examples from other success or failure stories; sharing the decision only concerning technicalities; and using plurals and authority. The findings suggest that shared decision-making may be advocated as a philosophical tenet or a value, but it is not necessarily implemented in actual communication with patients. Rather, treatment decisions tend to be unilaterally made, and a variety of persuasive approaches are used to ensure agreement with the physician's recommendation. The discussion is focused on the complexity of sharing a decision, especially in the initial bad news encounter

  14. Structure and Mechanism of Receptoe Sharing by the IL-10R2 Common Chain

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Sung-il; Jones, Brandi C.; Logsdon, Naomi J.; Harris, Bethany D.; Deshpande, Ashlesha; Radaeva, Svetlana; Halloran, Brian A.; Gao, Bin; Walter, Mark R. (NIH); (UAB)

    2010-06-14

    IL-10R2 is a shared cell surface receptor required for the activation of five class 2 cytokines (IL-10, IL-22, IL-26, IL-28, and IL-29) that play critical roles in host defense. To define the molecular mechanisms that regulate its promiscuous binding, we have determined the crystal structure of the IL-10R2 ectodomain at 2.14 {angstrom} resolution. IL-10R2 residues required for binding were identified by alanine scanning and used to derive computational models of IL-10/IL-10R1/IL-10R2 and IL-22/IL-22R1/IL-10R2 ternary complexes. The models reveal a conserved binding epitope that is surrounded by two clefts that accommodate the structural and chemical diversity of the cytokines. These results provide a structural framework for interpreting IL-10R2 single nucleotide polymorphisms associated with human disease.

  15. Structure and Mechanism of Receptor Sharing by the IL-10R2 Common Chain

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Sung-il; Jones, Brandi C.; Logsdon, Naomi J.; Harris, Bethany D.; Deshpande, Ashlesha; Radaeva, Svetlana; Halloran, Brian A.; Gao, Bin; Walter, Mark R. (NIH); (UAB)

    2010-07-19

    IL-10R2 is a shared cell surface receptor required for the activation of five class 2 cytokines (IL-10, IL-22, IL-26, IL-28, and IL-29) that play critical roles in host defense. To define the molecular mechanisms that regulate its promiscuous binding, we have determined the crystal structure of the IL-10R2 ectodomain at 2.14 {angstrom} resolution. IL-10R2 residues required for binding were identified by alanine scanning and used to derive computational models of IL-10/IL-10R1/IL-10R2 and IL-22/IL-22R1/IL-10R2 ternary complexes. The models reveal a conserved binding epitope that is surrounded by two clefts that accommodate the structural and chemical diversity of the cytokines. These results provide a structural framework for interpreting IL-10R2 single nucleotide polymorphisms associated with human disease.

  16. Price-Dynamics of Shares and Bohmian Mechanics: Deterministic or Stochastic Model?

    Science.gov (United States)

    Choustova, Olga

    2007-02-01

    We apply the mathematical formalism of Bohmian mechanics to describe dynamics of shares. The main distinguishing feature of the financial Bohmian model is the possibility to take into account market psychology by describing expectations of traders by the pilot wave. We also discuss some objections (coming from conventional financial mathematics of stochastic processes) against the deterministic Bohmian model. In particular, the objection that such a model contradicts to the efficient market hypothesis which is the cornerstone of the modern market ideology. Another objection is of pure mathematical nature: it is related to the quadratic variation of price trajectories. One possibility to reply to this critique is to consider the stochastic Bohm-Vigier model, instead of the deterministic one. We do this in the present note.

  17. Shared genetic aetiology of puberty timing between sexes and with health-related outcomes.

    Science.gov (United States)

    Day, Felix R; Bulik-Sullivan, Brendan; Hinds, David A; Finucane, Hilary K; Murabito, Joanne M; Tung, Joyce Y; Ong, Ken K; Perry, John R B

    2015-11-09

    Understanding of the genetic regulation of puberty timing has come largely from studies of rare disorders and population-based studies in women. Here, we report the largest genomic analysis for puberty timing in 55,871 men, based on recalled age at voice breaking. Analysis across all genomic variants reveals strong genetic correlation (0.74, P=2.7 × 10(-70)) between male and female puberty timing. However, some loci show sex-divergent effects, including directionally opposite effects between sexes at the SIM1/MCHR2 locus (Pheterogeneity=1.6 × 10(-12)). We find five novel loci for puberty timing (Ppuberty, LEPR and KAL1. Finally, we identify genetic correlations that indicate shared aetiologies in both sexes between puberty timing and body mass index, fasting insulin levels, lipid levels, type 2 diabetes and cardiovascular disease.

  18. Biological mechanisms, one molecule at a time

    Science.gov (United States)

    Tinoco, Ignacio; Gonzalez, Ruben L.

    2011-01-01

    The last 15 years have witnessed the development of tools that allow the observation and manipulation of single molecules. The rapidly expanding application of these technologies for investigating biological systems of ever-increasing complexity is revolutionizing our ability to probe the mechanisms of biological reactions. Here, we compare the mechanistic information available from single-molecule experiments with the information typically obtained from ensemble studies and show how these two experimental approaches interface with each other. We next present a basic overview of the toolkit for observing and manipulating biology one molecule at a time. We close by presenting a case study demonstrating the impact that single-molecule approaches have had on our understanding of one of life's most fundamental biochemical reactions: the translation of a messenger RNA into its encoded protein by the ribosome. PMID:21685361

  19. 47 CFR 25.259 - Time sharing between NOAA meteorological satellite systems and non-voice, non-geostationary...

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Time sharing between NOAA meteorological... SATELLITE COMMUNICATIONS Technical Standards § 25.259 Time sharing between NOAA meteorological satellite... Atmospheric Administration (“NOAA”) satellite systems. When calculating the protection areas for a NOAA...

  20. A Comparison of Job Satisfaction and General Well-Being for Job Sharing and Part-Time Female Employees.

    Science.gov (United States)

    Kane, Debbie

    1996-01-01

    Explores factors that influence how women cope with multiple roles. Discusses implications of a study that investigated job sharing as a part-time employment alternative for women (n=4 job-sharing nurses and n=4 part-time nurses) wanting a healthier balance between home and work life. (SNR)

  1. The Independent and Shared Mechanisms of Intrinsic Brain Dynamics: Insights From Bistable Perception

    Directory of Open Access Journals (Sweden)

    Teng Cao

    2018-04-01

    Full Text Available In bistable perception, constant input leads to alternating perception. The dynamics of the changing perception reflects the intrinsic dynamic properties of the “unconscious inferential” process in the brain. Under the same condition, individuals differ in how fast they experience the perceptual alternation. In this study, testing many forms of bistable perception in a large number of observers, we investigated the key question of whether there is a general and common mechanism or multiple and independent mechanisms that control the dynamics of the inferential brain. Bistable phenomena tested include binocular rivalry, vase-face, Necker cube, moving plaid, motion induced blindness, biological motion, spinning dancer, rotating cylinder, Lissajous-figure, rolling wheel, and translating diamond. Switching dynamics for each bistable percept was measured in 100 observers. Results show that the switching rates of subsets of bistable percept are highly correlated. The clustering of dynamic properties of some bistable phenomena but not an overall general control of switching dynamics implies that the brain’s inferential processes are both shared and independent – faster in constructing 3D structure from motion does not mean faster in integrating components into an objects.

  2. Analysis on Time Window of Shared Parking in Hospitals Based on Parking Behaviors

    Directory of Open Access Journals (Sweden)

    Qin Chen

    2017-01-01

    Full Text Available Hospitals are essential components of a city; huge traffic demand is generated and attracted, causing contradiction between parking supply and demand. By sharing parking berths, limited space can serve more demand which is beneficial to alleviating parking problems. Aimed at improving the capacity of shared parking, the paper analyzes four parking groups in typical hospitals, which are medical staff, outpatients, emergency patients, and visiting groups. The parking demand of medical staff is rigid. For outpatients and visiting groups, longer walking distance is acceptable and more attention is paid to parking fee. By contrast, emergency patients can accept shorter walking distance and focus more on convenience due to urgency. Under this circumstance, parking behaviors selection models are established by means of Multinomial Logit Model. On this basis, time value is adopted to calculate the tolerance of alterative parking time. Moreover, this paper explores the variation of time window, under different parking impedance. A case study is conducted and suggests that start and end point of a certain time window can be influenced by external factors.

  3. A Comprehensive Optimization Strategy for Real-time Spatial Feature Sharing and Visual Analytics in Cyberinfrastructure

    Science.gov (United States)

    Li, W.; Shao, H.

    2017-12-01

    For geospatial cyberinfrastructure enabled web services, the ability of rapidly transmitting and sharing spatial data over the Internet plays a critical role to meet the demands of real-time change detection, response and decision-making. Especially for the vector datasets which serve as irreplaceable and concrete material in data-driven geospatial applications, their rich geometry and property information facilitates the development of interactive, efficient and intelligent data analysis and visualization applications. However, the big-data issues of vector datasets have hindered their wide adoption in web services. In this research, we propose a comprehensive optimization strategy to enhance the performance of vector data transmitting and processing. This strategy combines: 1) pre- and on-the-fly generalization, which automatically determines proper simplification level through the introduction of appropriate distance tolerance (ADT) to meet various visualization requirements, and at the same time speed up simplification efficiency; 2) a progressive attribute transmission method to reduce data size and therefore the service response time; 3) compressed data transmission and dynamic adoption of a compression method to maximize the service efficiency under different computing and network environments. A cyberinfrastructure web portal was developed for implementing the proposed technologies. After applying our optimization strategies, substantial performance enhancement is achieved. We expect this work to widen the use of web service providing vector data to support real-time spatial feature sharing, visual analytics and decision-making.

  4. Individual Differences and Time-Sharing Ability: A Critical Review and Analysis.

    Science.gov (United States)

    1982-03-01

    the mythical innkeeper for which it is named. The paradigm involves the following steps: I) The user chooses a factor solution of interest as a "target...A) L L(T) L(C) LL L(A) A ACT ) A(C) Individual Differences and Time-Sharing Abilities Page 41 TABLE 21: LATENT ROOT PARALLEL A’ALYSIS -- DIFFERENCE...753 10 C(A) .350 11 L .711 12 L(T) .399 13 L(C) .650 14 LL .740 15 L(A) .521 16 A .504 17 ACT ) .489 18 A(C) .559 19 A(L) .545 7. FIGURE 1. LATENT

  5. Splitting hairs? Profit-sharing mechanisms in contracts under EC Competition Law

    International Nuclear Information System (INIS)

    Hancher, L.

    2008-01-01

    The focus in this article is on the potential competition law risks posed by various types of profit splitting mechanism clauses and the potential competition law risks associated with the drafting and enforcement of such clauses, and in particular the possible risks attached to any sharing of sensitive commercial information. These types of clauses are not uncommon in long-term LNG contracts. LNG is of course transported over long distances by ships, from a liquefaction plant to a re-gasification terminal. Profit-splitting mechanisms could however also be - and indeed have been - applied to pipeline sales. LNG transport permits greater flexibility as regards delivery a cargo can easily be diverted to a more attractive market before it reaches its destination. Furthermore, it is easier to monitor the destination of the cargo whereas pipeline gas is often impossible to track to a final destination once the gas has been delivered. Hence, sellers may attempt to maximise their returns on sales of LNG to different markets by incorporating some form of profit sharing mechanisms into their contracts in order to benefit from the proceeds of any diversion of the cargo to a higher priced market elsewhere in the European Union. Although this type of arrangement may make commercial sense for the seller, and indeed the seller's financial backers, seeking to maximise the returns on their investments, profit-splitting and price-sharing clauses can raise concerns under European competition law. In particular both the Commission and the European Courts have been concerned that any types of contracts may amount to a restriction on resale could either divide or partition the various national markets, thus frustrating the objective of ensuring undistorted competition throughout the internal market. Furthermore, European competition law has traditionally taken a tough line on resale price maintenance restrictions - contractual clauses that require a buyer to impose a certain price in

  6. A shared memory based interface of MARTe with EPICS for real-time applications

    International Nuclear Information System (INIS)

    Yun, Sangwon; Neto, André C.; Park, Mikyung; Lee, Sangil; Park, Kaprai

    2014-01-01

    Highlights: • We implemented a shared memory based interface of MARTe with EPICS. • We implemented an EPICS module supporting device and driver support. • We implemented an example EPICS IOC and CSS OPI for evaluation. - Abstract: The Multithreaded Application Real-Time executor (MARTe) is a multi-platform C++ middleware designed for the implementation of real-time control systems. It currently supports the Linux, Linux + RTAI, VxWorks, Solaris and MS Windows platforms. In the fusion community MARTe is being used at JET, COMPASS, ISTTOK, FTU and RFX in fusion [1]. The Experimental Physics and Industrial Control System (EPICS), a standard framework for the control systems in KSTAR and ITER, is a set of software tools and applications which provide a software infrastructure for use in building distributed control systems to operate devices. For a MARTe based application to cooperate with an EPICS based application, an interface layer between MARTe and EPICS is required. To solve this issue, a number of interfacing solutions have been proposed and some of them have been implemented. Nevertheless, a new approach is required to mitigate the functional limitations of existing solutions and to improve their performance for real-time applications. This paper describes the design and implementation of a shared memory based interface between MARTe and EPICS

  7. A shared memory based interface of MARTe with EPICS for real-time applications

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Sangwon, E-mail: yunsw@nfri.re.kr [National Fusion Research Institute (NFRI), Gwahangno 169-148, Yuseong-Gu, Daejeon 305-806 (Korea, Republic of); Neto, André C. [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa, P-1049-001 Lisboa (Portugal); Park, Mikyung; Lee, Sangil; Park, Kaprai [National Fusion Research Institute (NFRI), Gwahangno 169-148, Yuseong-Gu, Daejeon 305-806 (Korea, Republic of)

    2014-05-15

    Highlights: • We implemented a shared memory based interface of MARTe with EPICS. • We implemented an EPICS module supporting device and driver support. • We implemented an example EPICS IOC and CSS OPI for evaluation. - Abstract: The Multithreaded Application Real-Time executor (MARTe) is a multi-platform C++ middleware designed for the implementation of real-time control systems. It currently supports the Linux, Linux + RTAI, VxWorks, Solaris and MS Windows platforms. In the fusion community MARTe is being used at JET, COMPASS, ISTTOK, FTU and RFX in fusion [1]. The Experimental Physics and Industrial Control System (EPICS), a standard framework for the control systems in KSTAR and ITER, is a set of software tools and applications which provide a software infrastructure for use in building distributed control systems to operate devices. For a MARTe based application to cooperate with an EPICS based application, an interface layer between MARTe and EPICS is required. To solve this issue, a number of interfacing solutions have been proposed and some of them have been implemented. Nevertheless, a new approach is required to mitigate the functional limitations of existing solutions and to improve their performance for real-time applications. This paper describes the design and implementation of a shared memory based interface between MARTe and EPICS.

  8. Time Shared Optical Network (TSON): a novel metro architecture for flexible multi-granular services.

    Science.gov (United States)

    Zervas, Georgios S; Triay, Joan; Amaya, Norberto; Qin, Yixuan; Cervelló-Pastor, Cristina; Simeonidou, Dimitra

    2011-12-12

    This paper presents the Time Shared Optical Network (TSON) as metro mesh network architecture for guaranteed, statistically-multiplexed services. TSON proposes a flexible and tunable time-wavelength assignment along with one-way tree-based reservation and node architecture. It delivers guaranteed sub-wavelength and multi-granular network services without wavelength conversion, time-slice interchange and optical buffering. Simulation results demonstrate high network utilization, fast service delivery, and low end-to-end delay on a contention-free sub-wavelength optical transport network. In addition, implementation complexity in terms of Layer 2 aggregation, grooming and optical switching has been evaluated. © 2011 Optical Society of America

  9. Real-time telemedicine using shared three-dimensional workspaces over ATM

    Science.gov (United States)

    Cahoon, Peter; Forsey, David R.; Hutchison, Susan

    1999-03-01

    During the past five years a high speed ATM network has been developed at UBC that provides a campus testbed, a local testbed to the hospitals, and a National testbed between here and the BADLAB in Ottawa. This testbed has been developed to combine a commercial shared audio/video/whiteboard environment coupled with a shared interactive 3-dimensional solid model. This solid model ranges from a skull reconstructed from a CT scan with muscles and an overlying skin, to a model of the ventricle system of the human brain. Typical interactions among surgeon, radiologist and modeler consist of having image slices of the original scan shared by all and the ability to adjust the surface of the model to conform to each individuals perception of what the final object should look like. The purpose of this interaction can range from forensic reconstruction from partial remains to pre-maxillofacial surgery. A joint project with the forensic unit of the R.C.M.P. in Ottawa using the BADLAB is now in the stages of testing this methodology on a real case beginning with a CT scan of partial remains. A second study underway with the department of Maxiofacial reconstruction at Dalhousie University in Halifax Nova Scotia and concerns a subject who is about to undergo orthognathic surgery, in particular a mandibular advancement. This subject has been MRI scanned, a solid model constructed of the mandible and the virtual surgery constructed on the model. This model and the procedure have been discussed and modified by the modeler and the maxillofacial specialist using these shared workspaces. The procedure will be repeated after the actual surgery to verify the modeled procedure. The advantage of this technique is that none of the specialists need be in the same room, or city. Given the scarcity of time and specialists this methodology shows great promise. In November of this last year a shared live demonstration of this facial modeler was done between Vancouver and Dalhousie University in

  10. Shared or separate mechanisms for self-face and other-face processing? Evidence from adaptation.

    Directory of Open Access Journals (Sweden)

    Brendan eRooney

    2012-03-01

    Full Text Available Evidence that self-face recognition is dissociable from general face recognition hasimportant implications both for models of social cognition and for our understanding offace recognition. In two studies, we examine how adaptation affects the perception ofpersonally familiar faces, and we use a visual adaptation paradigm to investigatewhether the neural mechanisms underlying the recognition of one’s own and other facesare shared or separate. In Study 1 we show that the representation of personally familiarfaces is rapidly updated by visual experience with unfamiliar faces, so that theperception of one’s own face and a friend’s face is altered by a brief period ofadaptation to distorted unfamiliar faces. In Study 2, participants adapted to images oftheir own and a friend’s face distorted in opposite directions; the contingent aftereffectswe observe are indicative of separate neural populations, but we suggest that thesereflect coding of facial identity rather than of the categories ‘self’ and ‘other’.

  11. Chronic Pain and Mental Health Disorders: Shared Neural Mechanisms, Epidemiology, and Treatment.

    Science.gov (United States)

    Hooten, W Michael

    2016-07-01

    Chronic pain and mental health disorders are common in the general population, and epidemiological studies suggest that a bidirectional relationship exists between these 2 conditions. The observations from functional imaging studies suggest that this bidirectional relationship is due in part to shared neural mechanisms. In addition to depression, anxiety, and substance use disorders, individuals with chronic pain are at risk of other mental health problems including suicide and cigarette smoking and many have sustained sexual violence. Within the broader biopsychosocial model of pain, the fear-avoidance model explains how behavioral factors affect the temporal course of chronic pain and provides the framework for an array of efficacious behavioral interventions including cognitive-behavioral therapy, acceptance-based therapies, and multidisciplinary pain rehabilitation. Concomitant pain and mental health disorders often complicate pharmacological management, but several drug classes, including serotonin-norepinephrine reuptake inhibitors, tricyclic antidepressants, and anticonvulsants, have efficacy for both conditions and should be considered first-line treatment agents. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  12. Calculation of retention time tolerance windows with absolute confidence from shared liquid chromatographic retention data.

    Science.gov (United States)

    Boswell, Paul G; Abate-Pella, Daniel; Hewitt, Joshua T

    2015-09-18

    Compound identification by liquid chromatography-mass spectrometry (LC-MS) is a tedious process, mainly because authentic standards must be run on a user's system to be able to confidently reject a potential identity from its retention time and mass spectral properties. Instead, it would be preferable to use shared retention time/index data to narrow down the identity, but shared data cannot be used to reject candidates with an absolute level of confidence because the data are strongly affected by differences between HPLC systems and experimental conditions. However, a technique called "retention projection" was recently shown to account for many of the differences. In this manuscript, we discuss an approach to calculate appropriate retention time tolerance windows for projected retention times, potentially making it possible to exclude candidates with an absolute level of confidence, without needing to have authentic standards of each candidate on hand. In a range of multi-segment gradients and flow rates run among seven different labs, the new approach calculated tolerance windows that were significantly more appropriate for each retention projection than global tolerance windows calculated for retention projections or linear retention indices. Though there were still some small differences between the labs that evidently were not taken into account, the calculated tolerance windows only needed to be relaxed by 50% to make them appropriate for all labs. Even then, 42% of the tolerance windows calculated in this study without standards were narrower than those required by WADA for positive identification, where standards must be run contemporaneously. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Characteristics of a direct methanol fuel cell system with the time shared fuel supplying approach

    International Nuclear Information System (INIS)

    Na, Youngseung; Kwon, Jungmin; Kim, Hyun; Cho, Hyejung; Song, Inseob

    2013-01-01

    DMFC (direct methanol fuel cell) systems usually employ two pumps for supplying the methanol solution. The conventional system configuration, however, may bring about free flow from the methanol reservoir and malfunctions in the self-priming of the pumps. When instruments such as check valves and pressure regulators are applied, they result in excessive weight and control system malfunctions. In this paper, a light and robust DMFC system is proposed. By using the time sharing approach to supply fuel with a 3-way valve, free flow does not occur because only one inlet is opened at one time which means that both the circulation flow from gas liquid separator and the fuel flow from the methanol cartridge are not allowed to be opened at same time. As a result, back flow and self-priming problems do not occur. This makes the system stable and robust due to the removal of both the check valves and the fluctuation from unstable back pressure. Stabilized system doesn't need excessive battery buffering and recycling water any more, which are responsible for the heavy system. The proposed system performs the same level of power and efficiency with the conventional system. Adaptability is also carried out in various environmental temperature conditions. - Highlights: ►A light and robust DMFC system is proposed. ► The circulation pump is able to self-prime by itself after long term storage. ► The time sharing approach to supply fuel enables to control the methanol concentration precisely. ► The methanol concentration is controlled without free flow and the back flow from the fuel feeding pump. ► The excessive buffer of the batteries and the recycling water level are reduced

  14. Time-dependent fiber bundles with local load sharing. II. General Weibull fibers.

    Science.gov (United States)

    Phoenix, S Leigh; Newman, William I

    2009-12-01

    Fiber bundle models (FBMs) are useful tools in understanding failure processes in a variety of material systems. While the fibers and load sharing assumptions are easily described, FBM analysis is typically difficult. Monte Carlo methods are also hampered by the severe computational demands of large bundle sizes, which overwhelm just as behavior relevant to real materials starts to emerge. For large size scales, interest continues in idealized FBMs that assume either equal load sharing (ELS) or local load sharing (LLS) among fibers, rules that reflect features of real load redistribution in elastic lattices. The present work focuses on a one-dimensional bundle of N fibers under LLS where life consumption in a fiber follows a power law in its load, with exponent rho , and integrated over time. This life consumption function is further embodied in a functional form resulting in a Weibull distribution for lifetime under constant fiber stress and with Weibull exponent, beta. Thus the failure rate of a fiber depends on its past load history, except for beta=1 . We develop asymptotic results validated by Monte Carlo simulation using a computational algorithm developed in our previous work [Phys. Rev. E 63, 021507 (2001)] that greatly increases the size, N , of treatable bundles (e.g., 10(6) fibers in 10(3) realizations). In particular, our algorithm is O(N ln N) in contrast with former algorithms which were O(N2) making this investigation possible. Regimes are found for (beta,rho) pairs that yield contrasting behavior for large N. For rho>1 and large N, brittle weakest volume behavior emerges in terms of characteristic elements (groupings of fibers) derived from critical cluster formation, and the lifetime eventually goes to zero as N-->infinity , unlike ELS, which yields a finite limiting mean. For 1/21 but with 0

  15. Efficiency of performing pulmonary procedures in a shared endoscopy unit: procedure time, turnaround time, delays, and procedure waiting time.

    Science.gov (United States)

    Verma, Akash; Lee, Mui Yok; Wang, Chunhong; Hussein, Nurmalah B M; Selvi, Kalai; Tee, Augustine

    2014-04-01

    The purpose of this study was to assess the efficiency of performing pulmonary procedures in the endoscopy unit in a large teaching hospital. A prospective study from May 20 to July 19, 2013, was designed. The main outcome measures were procedure delays and their reasons, duration of procedural steps starting from patient's arrival to endoscopy unit, turnaround time, total case durations, and procedure wait time. A total of 65 procedures were observed. The most common procedure was BAL (61%) followed by TBLB (31%). Overall procedures for 35 (53.8%) of 65 patients were delayed by ≥ 30 minutes, 21/35 (60%) because of "spillover" of the gastrointestinal and surgical cases into the time block of pulmonary procedure. Time elapsed between end of pulmonary procedure and start of the next procedure was ≥ 30 minutes in 8/51 (16%) of cases. In 18/51 (35%) patients there was no next case in the room after completion of the pulmonary procedure. The average idle time of the room after the end of pulmonary procedure and start of next case or end of shift at 5:00 PM if no next case was 58 ± 53 minutes. In 17/51 (33%) patients the room's idle time was >60 minutes. A total of 52.3% of patients had the wait time >2 days and 11% had it ≥ 6 days, reason in 15/21 (71%) being unavailability of the slot. Most pulmonary procedures were delayed due to spillover of the gastrointestinal and surgical cases into the block time allocated to pulmonary procedures. The most common reason for difficulty encountered in scheduling the pulmonary procedure was slot unavailability. This caused increased procedure waiting time. The strategies to reduce procedure delays and turnaround times, along with improved scheduling methods, may have a favorable impact on the volume of procedures performed in the unit thereby optimizing the existing resources.

  16. Real-time sharing of gaze data between multiple eye trackers-evaluation, tools, and advice.

    Science.gov (United States)

    Nyström, Marcus; Niehorster, Diederick C; Cornelissen, Tim; Garde, Henrik

    2017-08-01

    Technological advancements in combination with significant reductions in price have made it practically feasible to run experiments with multiple eye trackers. This enables new types of experiments with simultaneous recordings of eye movement data from several participants, which is of interest for researchers in, e.g., social and educational psychology. The Lund University Humanities Laboratory recently acquired 25 remote eye trackers, which are connected over a local wireless network. As a first step toward running experiments with this setup, demanding situations with real time sharing of gaze data were investigated in terms of network performance as well as clock and screen synchronization. Results show that data can be shared with a sufficiently low packet loss (0.1 %) and latency (M = 3 ms, M A D = 2 ms) across 8 eye trackers at a rate of 60 Hz. For a similar performance using 24 computers, the send rate needs to be reduced to 20 Hz. To help researchers conduct similar measurements on their own multi-eye-tracker setup, open source software written in Python and PsychoPy are provided. Part of the software contains a minimal working example to help researchers kick-start experiments with two or more eye trackers.

  17. Shared genetic origins of allergy and autoimmune diseases

    DEFF Research Database (Denmark)

    Waage, J. E.; Kreiner-Møller, E.; Standl, M.

    2015-01-01

    Parallel increases in allergy and autoimmune disease prevalence in recent time suggest shared, but yet unknown, etiologies. Here, we investigated shared genetic loci and molecular pathways to identify possible shared disease mechanisms between allergy and autoimmune diseases.......Parallel increases in allergy and autoimmune disease prevalence in recent time suggest shared, but yet unknown, etiologies. Here, we investigated shared genetic loci and molecular pathways to identify possible shared disease mechanisms between allergy and autoimmune diseases....

  18. The 'time of occurrence' in quantum mechanics

    International Nuclear Information System (INIS)

    Srinivas, M.D.; Vijayalakshmi, R.

    1981-01-01

    Apart from serving as a parameter in describing the evolution of a system, time appears also as an observable property of a system in experiments where one measures 'the time of occurrence' of an event associated with the system. However, while the observables normally encountered in quantum theory (and characterized by self-adjoint operators or projection-valued measures) correspond to instantaneous measurements, a time of occurrence measurement involves continuous observations being performed on the system to monitor when the event occurs. It is argued that a time of occurrence observable should be represented by a positive-operator-valued measure on the interval over which the experiment is carried out. It is shown that while the requirement of time-translation invariance and the spectral condition rule out the possibility of a self-adjoint time operator (Pauli's theorem), they do allow for time of occurrence observables to be represented by suitable positive-operator-valued measures. It is also shown that the uncertainty in the time of occurrence of an event satisfies the time-energy uncertainty relation as a consequence of the time-translation invariance, only if the time of occurrence experiment is performed on the entire time axis. (author)

  19. Load sharing in distributed real-time systems with state-change broadcasts

    Science.gov (United States)

    Shin, Kang G.; Chang, Yi-Chieh

    1989-01-01

    A decentralized dynamic load-sharing (LS) method based on state-change broadcasts is proposed for a distributed real-time system. Whenever the state of a node changes from underloaded to fully loaded and vice versa, the node broadcasts this change to a set of nodes, called a buddy set, in the system. The performance of the method is evaluated with both analytic modeling and simulation. It is modeled first by an embedded Markov chain for which numerical solutions are derived. The model solutions are then used to calculate the distribution of queue lengths at the nodes and the probability of meeting task deadlines. The analytical results show that buddy sets of 10 nodes outperform those of less than 10 nodes, and the incremental benefit gained from increasing the buddy set size beyond 15 nodes is insignificant. These and other analytical results are verified by simulation. The proposed LS method is shown to meet task deadlines with a very high probability.

  20. Time-Sharing-Based Synchronization and Performance Evaluation of Color-Independent Visual-MIMO Communication.

    Science.gov (United States)

    Kwon, Tae-Ho; Kim, Jai-Eun; Kim, Ki-Doo

    2018-05-14

    In the field of communication, synchronization is always an important issue. The communication between a light-emitting diode (LED) array (LEA) and a camera is known as visual multiple-input multiple-output (MIMO), for which the data transmitter and receiver must be synchronized for seamless communication. In visual-MIMO, LEDs generally have a faster data rate than the camera. Hence, we propose an effective time-sharing-based synchronization technique with its color-independent characteristics providing the key to overcome this synchronization problem in visual-MIMO communication. We also evaluated the performance of our synchronization technique by varying the distance between the LEA and camera. A graphical analysis is also presented to compare the symbol error rate (SER) at different distances.

  1. Distinct and shared cognitive functions mediate event- and time-based prospective memory impairment in normal ageing

    Science.gov (United States)

    Gonneaud, Julie; Kalpouzos, Grégoria; Bon, Laetitia; Viader, Fausto; Eustache, Francis; Desgranges, Béatrice

    2011-01-01

    Prospective memory (PM) is the ability to remember to perform an action at a specific point in the future. Regarded as multidimensional, PM involves several cognitive functions that are known to be impaired in normal aging. In the present study, we set out to investigate the cognitive correlates of PM impairment in normal aging. Manipulating cognitive load, we assessed event- and time-based PM, as well as several cognitive functions, including executive functions, working memory and retrospective episodic memory, in healthy subjects covering the entire adulthood. We found that normal aging was characterized by PM decline in all conditions and that event-based PM was more sensitive to the effects of aging than time-based PM. Whatever the conditions, PM was linked to inhibition and processing speed. However, while event-based PM was mainly mediated by binding and retrospective memory processes, time-based PM was mainly related to inhibition. The only distinction between high- and low-load PM cognitive correlates lays in an additional, but marginal, correlation between updating and the high-load PM condition. The association of distinct cognitive functions, as well as shared mechanisms with event- and time-based PM confirms that each type of PM relies on a different set of processes. PMID:21678154

  2. Analysis of Information Sharing Mechanism in the Food Industry Green Supply Chain Management and Operation Process

    OpenAIRE

    Liu, Ye-ming; Yin, Fang-fang; Fu, Xian-zhi

    2011-01-01

    In order to effectively address the issues of environmental pollution and food safety in food industry, the green supply chain management should be used in the food industry. However, information sharing is the basis of supply chain management. For this purpose, on the basis of describing the connotation of food industry green supply chain management, the paper introduces the contents and the effects of information sharing mode in detail. It focuses on the barriers of the implementation of in...

  3. Quantum secret sharing based on modulated high-dimensional time-bin entanglement

    International Nuclear Information System (INIS)

    Takesue, Hiroki; Inoue, Kyo

    2006-01-01

    We propose a scheme for quantum secret sharing (QSS) that uses a modulated high-dimensional time-bin entanglement. By modulating the relative phase randomly by {0,π}, a sender with the entanglement source can randomly change the sign of the correlation of the measurement outcomes obtained by two distant recipients. The two recipients must cooperate if they are to obtain the sign of the correlation, which is used as a secret key. We show that our scheme is secure against intercept-and-resend (IR) and beam splitting attacks by an outside eavesdropper thanks to the nonorthogonality of high-dimensional time-bin entangled states. We also show that a cheating attempt based on an IR attack by one of the recipients can be detected by changing the dimension of the time-bin entanglement randomly and inserting two 'vacant' slots between the packets. Then, cheating attempts can be detected by monitoring the count rate in the vacant slots. The proposed scheme has better experimental feasibility than previously proposed entanglement-based QSS schemes

  4. Caribbean corals house shared and host-specific microbial symbionts over time and space.

    Science.gov (United States)

    Chu, Nathaniel D; Vollmer, Steven V

    2016-08-01

    The rise of coral diseases has triggered a surge of interest in coral microbial communities. But to fully understand how the coral microbiome may cause or respond to disease, we must first understand structure and variation in the healthy coral microbiome. We used 16S rRNA sequencing to characterize the microbiomes of 100 healthy coral colonies from six Caribbean coral species (Acropora cervicornis, A. palmata, Diploria labyrinthiformis, Diploria strigosa, Porites astreoides and P. furcata) across four reefs and three time points over 1 year. We found host species to be the strongest driver of coral microbiome structure across site and time. Analysis of the core microbiome revealed remarkable similarity in the bacterial taxa represented across coral hosts and many bacterial phylotypes shared across all corals sampled. Some of these widespread bacterial taxa have been identified in Pacific corals, indicating that a core coral microbiome may extend across oceans. Core bacterial phylotypes that were unique to each coral were taxonomically diverse, suggesting that different coral hosts provide persistent, divergent niches for bacteria. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  5. Group Clustering Mechanism for P2P Large Scale Data Sharing Collaboration

    Institute of Scientific and Technical Information of China (English)

    DENGQianni; LUXinda; CHENLi

    2005-01-01

    Research shows that P2P scientific collaboration network will exhibit small-world topology, as do a large number of social networks for which the same pattern has been documented. In this paper we propose a topology building protocol to benefit from the small world feature. We find that the idea of Freenet resembles the dynamic pattern of social interactions in scientific data sharing and the small world characteristic of Freenet is propitious to improve the file locating performance in scientificdata sharing. But the LRU (Least recently used) datas-tore cache replacement scheme of Freenet is not suitableto be used in scientific data sharing network. Based onthe group locality of scientific collaboration, we proposean enhanced group clustering cache replacement scheme.Simulation shows that this scheme improves the request hitratio dramatically while keeping the small average hops per successful request comparable to LRU.

  6. Expressing Environment Assumptions and Real-time Requirements for a Distributed Embedded System with Shared Variables

    DEFF Research Database (Denmark)

    Tjell, Simon; Fernandes, João Miguel

    2008-01-01

    In a distributed embedded system, it is often necessary to share variables among its computing nodes to allow the distribution of control algorithms. It is therefore necessary to include a component in each node that provides the service of variable sharing. For that type of component, this paper...

  7. Time dependent variational method in quantum mechanics

    International Nuclear Information System (INIS)

    Torres del Castillo, G.F.

    1987-01-01

    Using the fact that the solutions to the time-dependent Schodinger equation can be obtained from a variational principle, by restricting the evolution of the state vector to some surface in the corresponding Hilbert space, approximations to the exact solutions can be obtained, which are determined by equations similar to Hamilton's equations. It is shown that, in order for the approximate evolution to be well defined on a given surface, the imaginary part of the inner product restricted to the surface must be non-singular. (author)

  8. Time to consider sharing data extracted from trials included in systematic reviews

    Directory of Open Access Journals (Sweden)

    Luke Wolfenden

    2016-11-01

    Full Text Available Abstract Background While the debate regarding shared clinical trial data has shifted from whether such data should be shared to how this is best achieved, the sharing of data collected as part of systematic reviews has received little attention. In this commentary, we discuss the potential benefits of coordinated efforts to share data collected as part of systematic reviews. Main body There are a number of potential benefits of systematic review data sharing. Shared information and data obtained as part of the systematic review process may reduce unnecessary duplication, reduce demand on trialist to service repeated requests from reviewers for data, and improve the quality and efficiency of future reviews. Sharing also facilitates research to improve clinical trial and systematic review methods and supports additional analyses to address secondary research questions. While concerns regarding appropriate use of data, costs, or the academic return for original review authors may impede more open access to information extracted as part of systematic reviews, many of these issues are being addressed, and infrastructure to enable greater access to such information is being developed. Conclusion Embracing systems to enable more open access to systematic review data has considerable potential to maximise the benefits of research investment in undertaking systematic reviews.

  9. Bacterial intelligence: imitation games, time-sharing, and long-range quantum coherence.

    Science.gov (United States)

    Majumdar, Sarangam; Pal, Sukla

    2017-09-01

    Bacteria are far more intelligent than we can think of. They adopt different survival strategies to make their life comfortable. Researches on bacterial communication to date suggest that bacteria can communicate with each other using chemical signaling molecules as well as using ion channel mediated electrical signaling. Though in past few decades the scopes of chemical signaling have been investigated extensively, those of electrical signaling have received less attention. In this article, we present a novel perspective on time-sharing behavior, which maintains the biofilm growth under reduced nutrient supply between two distant biofilms through electrical signaling based on the experimental evidence reported by Liu et al., in 2017. In addition, following the recent work by Humphries et al. Cell 168(1):200-209, in 2017, we highlight the consequences of long range electrical signaling within biofilm communities through spatially propagating waves of potassium. Furthermore, we address the possibility of two-way cellular communication between artificial and natural cells through chemical signaling being inspired by recent experimental observation (Lentini et al. 2017) where the efficiency of artificial cells in imitating the natural cells is estimated through cellular Turing test. These three spectacular observations lead us to envisage and devise new classical and quantum views of these complex biochemical networks that have never been realized previously.

  10. Equipment calibration with a microprocessor connected to a time-sharing system

    International Nuclear Information System (INIS)

    Fontaine, G.; Guglielmi, L.; Jaeger, J.J.; Szafran, S.

    1981-01-01

    In H.E.P., it is common practice to test and calibrate equipment at different stages (design, construction checks, setting up and running periods) with a dedicated mini or micro-computer (such as CERN CAVIAR). An alternative solution has been developed in which such tasks are split between a microprocessor (Motorola 6800), and a host computer; this allows an easy and cheap multiplication of independant testing set-ups. The local processor is limited to CAMAC data acquisition, histogramming and simple processing, but its computing power is enhanced by a connection to a host time-sharing system via a MUMM multiplexor described in a separate paper. It is thus possible to perform sophisticated computations (fits etc...) and to use the host disk space to store calibration results for later use. In spite of the use of assembly language, a software structure has been devised to ease the constitution of an application program. This is achieved by the interplay of three levels of facilities: macro-instructions, library of subroutines, and Patchy controlled pieces of programs. A comprehensive collection of these is kept in the form of PAM files on the host computer. This system has been used to test calorimeter modules for the UA 1 experiment. (orig.)

  11. Circadian adaptations to meal timing: Neuroendocrine mechanisms

    Directory of Open Access Journals (Sweden)

    Danica F Patton

    2013-10-01

    Full Text Available Circadian rhythms of behavior and physiology are generated by central and peripheral circadian oscillators entrained by periodic environmental or physiological stimuli. A master circadian pacemaker in the hypothalamic suprachiasmatic nucleus is directly entrained by daily light-dark cycles, and coordinates the timing of other oscillators by direct and indirect neural, hormonal and behavioral outputs. The daily rhythm of food intake provides stimuli that entrain most peripheral and central oscillators, some of which can drive a daily rhythm of food anticipatory activity if food is restricted to one daily mealtime. The location of food-entrainable oscillators (FEOs that drive food anticipatory rhythms, and the food-related stimuli that entrain these oscillators, remain to be clarified. Here, we critically examine the role of peripheral metabolic hormones as potential internal entrainment stimuli or outputs for FEOs controlling food anticipatory rhythms in rats and mice. Hormones for which data are available include corticosterone, ghrelin, leptin, insulin, glucagon, and glucagon-like peptide 1. All of these hormones exhibit daily rhythms of synthesis and secretion that are synchronized by meal timing. There is some evidence that ghrelin and leptin modulate the expression of food anticipatory rhythms, but none of the hormones examined so far are necessary for entrainment. Ghrelin and leptin likely modulate food-entrained rhythms by actions in hypothalamic circuits utilizing melanocortin and orexin signaling, although again food-entrained behavioral rhythms can persist in lesion and gene knockout models in which these systems are disabled. Actions of these hormones on circadian oscillators in central reward circuits remain to be evaluated. Food-entrained activity rhythms are likely mediated by a distributed system of circadian oscillators sensitive to multiple feeding related inputs. Metabolic hormones appear to play a modulatory role within this

  12. Job Sharing: A Part-Time Career for a Fuller Life.

    Science.gov (United States)

    Koblinsky, Sally A.; Mikitka, Kathleen F.

    1984-01-01

    Describes job sharing as a rewarding alternative for those who wish to combine a career with child rearing, education, avocations, or leisure activities. Advantages and drawbacks for employers and suggestions for prospective job sharers are elaborated. (SK)

  13. Shared leadership

    DEFF Research Database (Denmark)

    Ulhøi, John Parm; Müller, Sabine

    2012-01-01

    The aim of this paper is twofold. First, this paper comprehensively will review the conceptual and empirical literature to identify such critical underlying mechanisms which enable shared or collective leadership. Second, this article identifies the antecedents and outcomes of shared leadership...... according to the literature review to develop a re-conceptualised and synthesized framework for managing the organizational issues associated with shared leadership on various organizational levels. The paper rectifies this by identifying the critical factors and mechanisms which enable shared leadership...... and its antecedents and outcomes, and to develop a re-conceptualized and synthesized framework of shared leadership. The paper closes with a brief discussion of avenues for future research and implications for managers....

  14. Quantum mechanics and stochastic mechanics for compatible observables at different times

    International Nuclear Information System (INIS)

    Correggi, M.; Morchio, G.

    2002-01-01

    Bohm mechanics and Nelson stochastic mechanics are confronted with quantum mechanics in the presence of noninteracting subsystems. In both cases, it is shown that correlations at different times of compatible position observables on stationary states agree with quantum mechanics only in the case of product wave functions. By appropriate Bell-like inequalities it is shown that no classical theory, in particular no stochastic process, can reproduce the quantum mechanical correlations of position variables of noninteracting systems at different times

  15. SKED software system. Revision D. Time-shared SUPERSKED. Manual 3

    Energy Technology Data Exchange (ETDEWEB)

    Snapper, A.G.; Inglis, G.

    1977-01-01

    A modified version of State Notation was developed for both hardware and software design of laboratory procedures involving control sequences that vary as a function of the behavior of the experimental subjects. The SKED program was refined and integrated into the OS/8 and time-share systems developed by DEC to take advantage of the development of mass-storage devices and the sophistication of the operating system. The current system consists of the mass-storage devices and the sophistication of the operating system. The current system consists of a two-pass compiler with an optional third-pass listing, a set of programs for identifying and merging data acquisition files, and a sophisticated system monitor that can be used to start, stop, load, and modify as many as 12 independent process control and data acquisition procedures. CCL was modified to accept standard DEC Execute, Compile, and Load commands with special switch options to control the compiling of procedures designed in state notation. Three different methods are available to acquire data from as many as 12 independent stations. The system includes a parameter file and dialog that permits the user to configure his system. Four different clocks, the UDC controller, EAE units, line-printers and other specialized devices may be included. The available memory may be partitioned between the process control section and the OS/8 background. Finally, the number of digital input and output interface lines may be assigned to 12 stations in a flexible manner, by means of an interactive dialog. The system can be configured on any BK OS/8 machine or in the background. 44 figures, 28 tables.

  16. Introduction to quantum mechanics a time-dependent perspective

    CERN Document Server

    Tannor, David J

    2007-01-01

    "Introduction to Quantum Mechanics" covers quantum mechanics from a time-dependent perspective in a unified way from beginning to end. Intended for upper-level undergraduate and graduate courses this text will change the way people think about and teach quantum mechanics in chemistry and physics departments.

  17. Concurrent multidisciplinary mechanical design based on design task analysis and knowledge sharing; Sekkei task bunseki to joho kyoyu ni yoru mechatronics kyocho sekkei

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, K.; Ozawa, M.; Mori, T. [Toshiba Corp., Tokyo (Japan)

    1999-09-01

    We have developed a systematic design task planning method based on a design structure matrix(DSM) and a lumped model- based framework for knowledge sharing in a concurrent design environment as key techniques for developing higher quality products in a shorter design time. The DSM facilitates systematic analysis of dependencies among design tasks and optimization of the design process. The framework based on a lumped model description of mechanical systems enables concurrent and cooperative work among multidisciplinary designers at an early stage of the design process. In this paper, we also discuss the relationships between these techniques and the product development flow from product definition to detailed design. (author)

  18. Effect of curing time on microstructure and mechanical strength ...

    Indian Academy of Sciences (India)

    The aim of this paper is to study the influence of curing time on the microstructure and mechanical strength development of alkali activated binders based on vitreous calcium aluminosilicate (VCAS). Mechanical strength of alkali activated mortars cured at 65 °C was assessed for different curing times (4–168 h) using 10 ...

  19. Expressing Environment Assumptions and Real-time Requirements for a Distributed Embedded System with Shared Variables

    DEFF Research Database (Denmark)

    Tjell, Simon; Fernandes, João Miguel

    2008-01-01

    In a distributed embedded system, it is often necessary to share variables among its computing nodes to allow the distribution of control algorithms. It is therefore necessary to include a component in each node that provides the service of variable sharing. For that type of component, this paper...... for the component. The CPN model can be used to validate the environment assumptions and the requirements. The validation is performed by execution of the model during which traces of events and states are automatically generated and evaluated against the requirements....

  20. Regulatory design for RES-E support mechanisms: Learning curves, market structure, and burden-sharing

    International Nuclear Information System (INIS)

    Batlle, C.; Pérez-Arriaga, I.J.; Zambrano-Barragán, P.

    2012-01-01

    Drawing from relevant experiences in power systems around the world, this paper offers a review of existing policy support mechanisms for RES-E, with a detailed analysis of their regulatory implications. While recent studies provide an account of current RES-E support systems, in this paper we focus on some of the impacts these mechanisms have on the overall energy market structure and its performance. Given the rising importance of RES-E in systems everywhere, these impacts should no longer be overlooked. - Highlights: ► This paper offers a critical review of RES-E support mechanisms and their regulatory implications. ► The discussion focuses on how the different schemes impact the performance of the energy markets. ► We propose to redesign of current RES-E mechanisms to optimize incentives and market performance. ► Our recommendation is also to gradually move from price-based mechanisms to auctions.

  1. Towards mutual trust, transparency and equity in virus sharing mechanism: the avian influenza case of Indonesia.

    Science.gov (United States)

    Sedyaningsih, Endang R; Isfandari, Siti; Soendoro, Triono; Supari, Siti Fadilah

    2008-06-01

    As the country hardest hit by avian influenza, both in poultry and in human, Indonesia's decision to withhold samples of avian influenza virus A (H5N1) has fired up a global controversy. The objective of this paper is to describe the position taken by Indonesia in the events leading to the decision and in those conducted to resolve the situation. The sources for this paper are the Indonesian human influenza A(H5N1) case reports and study results, summaries, minutes and reports of national and international meetings of virus sharing, and other related Indonesian and WHO documents. The International Health Regulations 2005 have been applied in different ways based on different interpretations. While one party insists on the importance of free, non-conditional, virus sharing for risk assessment and risk response, Indonesia--as supported by most of the developing countries--stresses on the more basic principles such as sovereignty of a country over its biological materials, transparency of the global system, and equity between developed and developing nations. This event demonstrates the unresolved imbalance between the affluent high-tech countries and the poor agriculture-based countries. Regional, global and in-country meetings must continue to be conducted to find solutions acceptable to all.

  2. Design of Ontology-Based Sharing Mechanism for Web Services Recommendation Learning Environment

    Science.gov (United States)

    Chen, Hong-Ren

    The number of digital learning websites is growing as a result of advances in computer technology and new techniques in web page creation. These sites contain a wide variety of information but may be a source of confusion to learners who fail to find the information they are seeking. This has led to the concept of recommendation services to help learners acquire information and learning resources that suit their requirements. Learning content like this cannot be reused by other digital learning websites. A successful recommendation service that satisfies a certain learner must cooperate with many other digital learning objects so that it can achieve the required relevance. The study proposes using the theory of knowledge construction in ontology to make the sharing and reuse of digital learning resources possible. The learning recommendation system is accompanied by the recommendation of appropriate teaching materials to help learners enhance their learning abilities. A variety of diverse learning components scattered across the Internet can be organized through an ontological process so that learners can use information by storing, sharing, and reusing it.

  3. Explicit time integration of finite element models on a vectorized, concurrent computer with shared memory

    Science.gov (United States)

    Gilbertsen, Noreen D.; Belytschko, Ted

    1990-01-01

    The implementation of a nonlinear explicit program on a vectorized, concurrent computer with shared memory is described and studied. The conflict between vectorization and concurrency is described and some guidelines are given for optimal block sizes. Several example problems are summarized to illustrate the types of speed-ups which can be achieved by reprogramming as compared to compiler optimization.

  4. Secure Real-Time Monitoring and Management of Smart Distribution Grid using Shared Cellular Networks

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Ganem, Hervé; Jorguseski, Ljupco

    2017-01-01

    capabilities. Thanks to the advanced measurement devices, management framework, and secure communication infrastructure developed in the FP7 SUNSEED project, the Distribution System Operator (DSO) now has full observability of the energy flows at the medium/low voltage grid. Furthermore, the prosumers are able......, where the smart grid ICT solutions are provided through shared cellular LTE networks....

  5. Insensitive bounds for the moments of the sojourn time distribution in the M/G/1 processor-sharing queue

    NARCIS (Netherlands)

    Cheung, S.K.; Berg, J.L. van den; Boucherie, R.J.

    2006-01-01

    This paper studies the M/G/1 processor-sharing (PS) queue, in particular the sojourn time distribution conditioned on the initial job size. Although several expressions for the Laplace-Stieltjes transform (LST) are known, these expressions are not suitable for computational purposes. This paper

  6. Insensitive bounds for the moments of the sojourn time distribution in the M/G/1 processor-sharing queue

    NARCIS (Netherlands)

    Cheung, S.K.; van den Berg, Hans Leo; Boucherie, Richardus J.

    2005-01-01

    This paper studies the M/G/1 processor-sharing (PS) queue and the sojourn time distribution conditioned on the initial job size. Although several expressions for the Laplace-Stieltjes transform (LST) are known, these expressions are not applicable for computational purposes. This paper derives

  7. Navajo Code Talker Joe Morris, Sr. shared insights from his time as a secret World War Two messenger

    Science.gov (United States)

    2002-01-01

    Navajo Code Talker Joe Morris, Sr. shared insights from his time as a secret World War Two messenger with his audience at NASA's Dryden Flight Research Center on Nov. 26, 2002. NASA Dryden is located on Edwards Air Force Base in California's Mojave Desert.

  8. Insensitive bounds for the moments of the sojourn time distribution in the M/G/1 processor-sharing queue

    NARCIS (Netherlands)

    Cheung, S.K.; Cheung, S.K.; van den Berg, Hans Leo; Boucherie, Richardus J.

    This paper studies the M/G/1 processor-sharing (PS) queue, in particular the sojourn time distribution conditioned on the initial job size. Although several expressions for the Laplace-Stieltjes transform (LST) are known, these expressions are not suitable for computational purposes. This paper

  9. Evaluation of a Connectionless NoC for a Real-Time Distributed Shared Memory Many-Core System

    NARCIS (Netherlands)

    Rutgers, J.H.; Bekooij, Marco Jan Gerrit; Smit, Gerardus Johannes Maria

    2012-01-01

    Real-time embedded systems like smartphones tend to comprise an ever increasing number of processing cores. For scalability and the need for guaranteed performance, the use of a connection-oriented network-on-chip (NoC) is advocated. Furthermore, a distributed shared memory architecture is preferred

  10. Features of the broader autism phenotype in people with epilepsy support shared mechanisms between epilepsy and autism spectrum disorder.

    Science.gov (United States)

    Richard, Annie E; Scheffer, Ingrid E; Wilson, Sarah J

    2017-04-01

    Richard, A.E., I.E. Scheffer and S.J. Wilson. Features of the broader autism phenotype in people with epilepsy support shared mechanisms between epilepsy and autism spectrum disorder. NEUROSCI BIOBEHAV REV 21(1) XXX-XXX, 2016. To inform on mechanisms underlying the comorbidity of epilepsy and autism spectrum disorder (ASD), we conducted meta-analyses to test whether impaired facial emotion recognition (FER) and theory of mind (ToM), key phenotypic traits of ASD, are more common in people with epilepsy (PWE) than controls. We contrasted these findings with those of relatives of individuals with ASD (ASD-relatives) compared to controls. Furthermore, we examined the relationship of demographic (age, IQ, sex) and epilepsy-related factors (epilepsy onset age, duration, seizure laterality and origin) to FER and ToM. Thirty-one eligible studies of PWE (including 1449 individuals: 77% with temporal lobe epilepsy), and 22 of ASD-relatives (N=1295) were identified by a systematic database search. Analyses revealed reduced FER and ToM in PWE compared to controls (p<0.001), but only reduced ToM in ASD-relatives (p<0.001). ToM was poorer in PWE than ASD-relatives. Only weak associations were found between FER and ToM and epilepsy-related factors. These findings suggest shared mechanisms between epilepsy and ASD, independent of intellectual disability. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Time in quantum mechanics. Vol. 1. 2. ed.

    International Nuclear Information System (INIS)

    Muga, J.G.; Sala Mayato, R.; Egusquiza, I.L.

    2008-01-01

    The treatment of time in quantum mechanics is still an important and challenging open question in the foundation of the quantum theory. This book describes the problems, and the attempts and achievements in defining, formalizing and measuring different time quantities in quantum theory, such as the parametric (clock) time, tunneling times, decay times, dwell times, delay times, arrival times or jump times. This multi-authored book, written as an introductory guide for newcomers to the subject, as well as a useful source of information for the expert, covers many of the open questions. After the brief historical overview in the introduction, 12 contributions are devoted to conceptual and theoretical investigations as well as experimental issues in quantum-mechanical time measurements. This novel monograph should attract physicists as well as philosophers of science working in the foundations of quantum physics. For this revised second edition, all chapters have been updated and extended where appropriate. (orig.)

  12. Evidence for a Shared Mechanism in the Formation of Urea-Induced Kinetic and Equilibrium Intermediates of Horse Apomyoglobin from Ultrarapid Mixing Experiments

    Science.gov (United States)

    Mizukami, Takuya; Abe, Yukiko; Maki, Kosuke

    2015-01-01

    In this study, the equivalence of the kinetic mechanisms of the formation of urea-induced kinetic folding intermediates and non-native equilibrium states was investigated in apomyoglobin. Despite having similar structural properties, equilibrium and kinetic intermediates accumulate under different conditions and via different mechanisms, and it remains unknown whether their formation involves shared or distinct kinetic mechanisms. To investigate the potential mechanisms of formation, the refolding and unfolding kinetics of horse apomyoglobin were measured by continuous- and stopped-flow fluorescence over a time range from approximately 100 μs to 10 s, along with equilibrium unfolding transitions, as a function of urea concentration at pH 6.0 and 8°C. The formation of a kinetic intermediate was observed over a wider range of urea concentrations (0–2.2 M) than the formation of the native state (0–1.6 M). Additionally, the kinetic intermediate remained populated as the predominant equilibrium state under conditions where the native and unfolded states were unstable (at ~0.7–2 M urea). A continuous shift from the kinetic to the equilibrium intermediate was observed as urea concentrations increased from 0 M to ~2 M, which indicates that these states share a common kinetic folding mechanism. This finding supports the conclusion that these intermediates are equivalent. Our results in turn suggest that the regions of the protein that resist denaturant perturbations form during the earlier stages of folding, which further supports the structural equivalence of transient and equilibrium intermediates. An additional folding intermediate accumulated within ~140 μs of refolding and an unfolding intermediate accumulated in <1 ms of unfolding. Finally, by using quantitative modeling, we showed that a five-state sequential scheme appropriately describes the folding mechanism of horse apomyoglobin. PMID:26244984

  13. On the definition of time operator in quantum mechanics

    International Nuclear Information System (INIS)

    Nowicki, A.A.

    1974-01-01

    Different approaches to the quantum-mechanical definition of time operator T are briefly discussed. In particular we define the analytic continuation of the time operator and show that one can construct its exact eigenstates. We consider also the case of a relativistic free scalar particle and discuss the notion of proper time operator S. (author)

  14. Immune regulation of systemic hypertension, pulmonary arterial hypertension, and preeclampsia: shared disease mechanisms and translational opportunities.

    Science.gov (United States)

    Jafri, Salema; Ormiston, Mark L

    2017-12-01

    Systemic hypertension, preeclampsia, and pulmonary arterial hypertension (PAH) are diseases of high blood pressure in the systemic or pulmonary circulation. Beyond the well-defined contribution of more traditional pathophysiological mechanisms, such as changes in the renin-angiotensin-aldosterone system, to the development of these hypertensive disorders, there is substantial clinical evidence supporting an important role for inflammation and immunity in the pathogenesis of each of these three conditions. Over the last decade, work in small animal models, bearing targeted deficiencies in specific cytokines or immune cell subsets, has begun to clarify the immune-mediated mechanisms that drive changes in vascular structure and tone in hypertensive disease. By summarizing the clinical and experimental evidence supporting a contribution of the immune system to systemic hypertension, preeclampsia, and PAH, the current review highlights the cellular and molecular pathways that are common to all three hypertensive disorders. These mechanisms are centered on an imbalance in CD4 + helper T cell populations, defined by excessive Th17 responses and impaired T reg activity, as well as the excessive activation or impairment of additional immune cell types, including macrophages, dendritic cells, CD8 + T cells, B cells, and natural killer cells. The identification of common immune mechanisms in systemic hypertension, preeclampsia, and PAH raises the possibility of new therapeutic strategies that target the immune component of hypertension across multiple disorders. Copyright © 2017 the American Physiological Society.

  15. Skinner-Rusk approach to time-dependent mechanics

    NARCIS (Netherlands)

    Cortés, Jorge; Martínez, Sonia; Cantrijn, Frans

    2002-01-01

    The geometric approach to autonomous classical mechanical systems in terms of a canonical first-order system on the Whitney sum of the tangent and cotangent bundle, developed by Skinner and Rusk, is extended to the time-dependent framework.

  16. Real-time observations of mechanical stimulus-induced enhancements of mechanical properties in osteoblast cells

    International Nuclear Information System (INIS)

    Zhang Xu; Liu Xiaoli; Sun Jialun; He Shuojie; Lee, Imshik; Pak, Hyuk Kyu

    2008-01-01

    Osteoblast, playing a key role in the pathophysiology of osteoporosis, is one of the mechanical stress sensitive cells. The effects of mechanical load-induced changes of mechanical properties in osteoblast cells were studied at real-time. Osteoblasts obtained from young Wister rats were exposed to mechanical loads in different frequencies and resting intervals generated by atomic force microscopy (AFM) probe tip and simultaneously measured the changes of the mechanical properties by AFM. The enhancement of the mechanical properties was observed and quantified by the increment of the apparent Young's modulus, E * . The observed mechanical property depended on the frequency of applied tapping loads. For the resting interval is 50 s, the mechanical load-induced enhancement of E * -values disappears. It seems that the enhanced mechanical property was recover able under no additional mechanical stimulus

  17. Joint effects of asymmetric payoff and reciprocity mechanisms on collective cooperation in water sharing interactions: a game theoretic perspective.

    Directory of Open Access Journals (Sweden)

    Cho Nam Ng

    Full Text Available Common-pool resource (CPR dilemmas distinguish themselves from general public good problems by encompassing both social and physical features. This paper examines how a physical mechanism, namely asymmetric payoff; and a social mechanism, reciprocity; simultaneously affect collective cooperation in theoretical water sharing interactions. We present an iterative N-person game theoretic model to investigate the joint effects of these two mechanisms in a linear fully connected river system under three information assumptions. From a simple evolutionary perspective, this paper quantitatively addresses the conditions for Nash Equilibrium in which collective cooperation might be established. The results suggest that direct reciprocity increases every actor's motivation to contribute to the collective good of the river system. Meanwhile, various upstream and downstream actors manifest individual disparities as a result of the direct reciprocity and asymmetric payoff mechanisms. More specifically, the downstream actors are less willing to cooperate unless there is a high probability that long-term interactions are ensured; however, a greater level of asymmetries is likely to increase upstream actors' incentives to cooperate even though the interactions could quickly end. The upstream actors also display weak sensitivity to an increase in the total number of actors, which generally results in a reduction in the other actors' motivation for cooperation. It is also shown that the indirect reciprocity mechanism relaxes the overall conditions for cooperative Nash Equilibrium.

  18. How the Senate and the President Affect the Timing of Power-sharing Rule Changes in the US House

    OpenAIRE

    Gisela Sin; Arthur Lupia

    2013-01-01

    A new model and related empirical work explain how the Senate and President affect the timing of power-sharing rule changes in the US House. We argue that shifts in the Senate's or President's preferences (e.g., a new majority party in the Senate; a new president) reshape House members' expectations about which legislative outcomes are achievable. Reshaped expectations, in turn, can alter House members' perceptions of the consequences of reallocating power among themselves. We prove that such...

  19. C. elegans germline-deficient mutants respond to pathogen infection using shared and distinct mechanisms.

    Directory of Open Access Journals (Sweden)

    Michael TeKippe

    2010-07-01

    Full Text Available Reproduction extracts a cost in resources that organisms are then unable to utilize to deal with a multitude of environmental stressors. In the nematode C. elegans, development of the germline shortens the lifespan of the animal and increases its susceptibility to microbial pathogens. Prior studies have demonstrated germline-deficient nematodes to have increased resistance to gram negative bacteria. We show that germline-deficient strains display increased resistance across a broad range of pathogens including gram positive and gram negative bacteria, and the fungal pathogen Cryptococcus neoformans. Furthermore, we show that the FOXO transcription factor DAF-16, which regulates longevity and immunity in C. elegans, appears to be crucial for maintaining longevity in both wild-type and germline-deficient backgrounds. Our studies indicate that germline-deficient mutants glp-1 and glp-4 respond to pathogen infection using common and different mechanisms that involve the activation of DAF-16.

  20. Student Understanding of Time Dependence in Quantum Mechanics

    Science.gov (United States)

    Emigh, Paul J.; Passante, Gina; Shaffer, Peter S.

    2015-01-01

    The time evolution of quantum states is arguably one of the more difficult ideas in quantum mechanics. In this article, we report on results from an investigation of student understanding of this topic after lecture instruction. We demonstrate specific problems that students have in applying time dependence to quantum systems and in recognizing…

  1. On the role of time in nonrelativistic quantum mechanics

    International Nuclear Information System (INIS)

    Chattaraj, P.K.; Sannigrahi, A.B.

    1994-01-01

    It has been didactically analysed that time appears as a parameter in nonrelativistic quantum mechanics. Corresponding Heisenberg's uncertainty principle is discussed. Dynamical behaviour of time and its operator equivalence are generally obtained from analogy and should not be treated at par with other dynamical observables, e.g. momentum. (author). 8 refs

  2. Toward a Conceptual Model for Social Mechanisms Enabling Knowledge Sharing: Dynamic Relationships among Three Dimensions of Social Capital

    Science.gov (United States)

    Jo, Sung Jun

    2008-01-01

    Knowledge sharing is important because individual knowledge is not transformed into organizational knowledge until it is shared. The conceptual model presents how social factors create the conditions for effective knowledge sharing. It illustrates how three dimensions of social capital impact with each other and with knowledge sharing. Social…

  3. Part-time work and job sharing in health care: is the NHS a family-friendly employer?

    Science.gov (United States)

    Branine, Mohamed

    2003-01-01

    This paper examines the nature and level of flexible employment in the National Health Service (NHS) by investigating the extent to which part-time work and job sharing arrangements are used in the provision and delivery of health care. It attempts to analyse the reasons for an increasing number of part-timers and a very limited number of job sharers in the NHS and to explain the advantages and disadvantages of each pattern of employment. Data collected through the use of questionnaires and interviews from 55 NHS trusts reveal that the use of part-time work is a tradition that seems to fit well with the cost-saving measures imposed on the management of the service but at the same time it has led to increasing employee dissatisfaction, and that job sharing arrangements are suitable for many NHS employees since the majority of them are women with a desire to combine family commitments with career prospects but a very limited number of employees have had the opportunity to job share. Therefore it is concluded that to attract and retain the quality of staff needed to ensure high performance standards in the provision and delivery of health care the NHS should accept the diversity that exists within its workforce and take a more proactive approach to promoting a variety of flexible working practices and family-friendly policies.

  4. Mechanism and Therapy for the Shared Susceptibility to Migraine and Epilepsy after Traumatic Brain Injury (TBI)

    Science.gov (United States)

    2013-10-01

    and 7 days post injury time point. Figure 20 shows the typical lesion pattern following our protocol. Figure 21 shows Nissl stain at different...diameter. Figure 21. Light microscopy images of Nissl stain displaying lesion area 1 week following impact in WT (Stat3-LoxP) and KO (Stat3-LoxP-Cre...cryoprotectant solution pending further processing. Every third section was collected to quantify infarct volumes using cresyl violet ( Nissl ) stain (Ohab et

  5. Attosecond delays in photoionization: time and quantum mechanics

    International Nuclear Information System (INIS)

    Maquet, Alfred; Caillat, Jérémie; Taïeb, Richard

    2014-01-01

    This article addresses topics regarding time measurements performed on quantum systems. The motivation is linked to the advent of ‘attophysics’ which makes feasible to follow the motion of electrons in atoms and molecules, with time resolution at the attosecond (1 as = 10 −18 s) level, i.e. at the natural scale for electronic processes in these systems. In this context, attosecond ‘time-delays’ have been recently measured in experiments on photoionization and the question arises if such advances could cast a new light on the still active discussion on the status of the time variable in quantum mechanics. One issue still debatable is how to decide whether one can define a quantum time operator with eigenvalues associated to measurable ‘time-delays’, or time is a parameter, as it is implicit in the Newtonian classical mechanics. One objective of this paper is to investigate if the recent attophysics-based measurements could shed light on this parameter–operator conundrum. To this end, we present here the main features of the theory background, followed by an analysis of the experimental schemes that have been used to evidence attosecond ‘time-delays’ in photoionization. Our conclusion is that these results reinforce the view that time is a parameter which cannot be defined without reference to classical mechanics. (tutorial)

  6. Time-dependent reliability sensitivity analysis of motion mechanisms

    International Nuclear Information System (INIS)

    Wei, Pengfei; Song, Jingwen; Lu, Zhenzhou; Yue, Zhufeng

    2016-01-01

    Reliability sensitivity analysis aims at identifying the source of structure/mechanism failure, and quantifying the effects of each random source or their distribution parameters on failure probability or reliability. In this paper, the time-dependent parametric reliability sensitivity (PRS) analysis as well as the global reliability sensitivity (GRS) analysis is introduced for the motion mechanisms. The PRS indices are defined as the partial derivatives of the time-dependent reliability w.r.t. the distribution parameters of each random input variable, and they quantify the effect of the small change of each distribution parameter on the time-dependent reliability. The GRS indices are defined for quantifying the individual, interaction and total contributions of the uncertainty in each random input variable to the time-dependent reliability. The envelope function method combined with the first order approximation of the motion error function is introduced for efficiently estimating the time-dependent PRS and GRS indices. Both the time-dependent PRS and GRS analysis techniques can be especially useful for reliability-based design. This significance of the proposed methods as well as the effectiveness of the envelope function method for estimating the time-dependent PRS and GRS indices are demonstrated with a four-bar mechanism and a car rack-and-pinion steering linkage. - Highlights: • Time-dependent parametric reliability sensitivity analysis is presented. • Time-dependent global reliability sensitivity analysis is presented for mechanisms. • The proposed method is especially useful for enhancing the kinematic reliability. • An envelope method is introduced for efficiently implementing the proposed methods. • The proposed method is demonstrated by two real planar mechanisms.

  7. A Karaoke System with Real-Time Media Merging and Sharing Functions for a Cloud-Computing-Integrated Mobile Device

    Directory of Open Access Journals (Sweden)

    Her-Tyan Yeh

    2013-01-01

    Full Text Available Mobile devices such as personal digital assistants (PDAs, smartphones, and tablets have increased in popularity and are extremely efficient for work-related, social, and entertainment uses. Popular entertainment services have also attracted substantial attention. Thus, relevant industries have exerted considerable efforts in establishing a method by which mobile devices can be used to develop excellent and convenient entertainment services. Because cloud-computing technology is mature and possesses a strong computing processing capacity, integrating this technology into the entertainment service function in mobile devices can reduce the data load on a system and maintain mobile device performances. This study combines cloud computing with a mobile device to design a karaoke system that contains real-time media merging and sharing functions. This system enables users to download music videos (MVs from their mobile device and sing and record their singing by using the device. They can upload the recorded song to the cloud server where it is merged with real-time media. Subsequently, by employing a media streaming technology, users can store their personal MVs in their mobile device or computer and instantaneously share these videos with others on the Internet. Through this process, people can instantly watch shared videos, enjoy the leisure and entertainment effects of mobile devices, and satisfy their desire for singing.

  8. An ERP study of structural anomalies in native and semantic free artificial grammar: evidence for shared processing mechanisms.

    Science.gov (United States)

    Tabullo, Ángel; Sevilla, Yamila; Segura, Enrique; Zanutto, Silvano; Wainselboim, Alejandro

    2013-08-21

    Artificial grammars have been widely applied to the study of sequential learning in language, but few studies have directly compared the neural correlates of artificial and native grammar processing. In this study, we examined Event Related Potentials (ERPs) elicited by structural anomalies in semantic-free artificial grammar sequences and sentences in the subjects' native language (Spanish). Although ERPs differed during early stages, we observed similar posterior negativities (N400) and P600 effects in a late stage. We interpret these results as evidence of at least partially shared neural mechanisms for processing of language and artificial grammars. We suggest that in both the natural and artificial grammars, the N400 and P600 components we observed can be explained as the result of unfulfilled predictions about incoming stimuli. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Parent-Child Shared Time From Middle Childhood to Late Adolescence: Developmental Course and Adjustment Correlates

    Science.gov (United States)

    Lam, Chun Bun; McHale, Susan M.; Crouter, Ann C.

    2012-01-01

    The development and adjustment correlates of parent-child social (parent, child, and others present) and dyadic time (only parent and child present) from age 8 to 18 were examined. Mothers, fathers, and firstborns and secondborns from 188 White families participated in both home and nightly phone interviews. Social time declined across adolescence, but dyadic time with mothers and fathers peaked in early and middle adolescence, respectively. Additionally, secondborns’ social time declined more slowly than firstborns’, and gendered time use patterns were more pronounced in boys and in opposite-sex sibling dyads. Finally, youths who spent more dyadic time with their fathers, on average, had higher general self-worth, and changes in social time with fathers were positively linked to changes in social competence. PMID:22925042

  10. Parent-child shared time from middle childhood to late adolescence: developmental course and adjustment correlates.

    Science.gov (United States)

    Lam, Chun Bun; McHale, Susan M; Crouter, Ann C

    2012-11-01

    The development and adjustment correlates of parent-child social (parent, child, and others present) and dyadic time (only parent and child present) from age 8 to 18 were examined. Mothers, fathers, and firstborns and secondborns from 188 White families participated in both home and nightly phone interviews. Social time declined across adolescence, but dyadic time with mothers and fathers peaked in early and middle adolescence, respectively. In addition, secondborns' social time declined more slowly than firstborns', and gendered time use patterns were more pronounced in boys and in opposite-sex sibling dyads. Finally, youths who spent more dyadic time with their fathers, on average, had higher general self-worth, and changes in social time with fathers were positively linked to changes in social competence. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

  11. Biological timing and the clock metaphor: oscillatory and hourglass mechanisms.

    Science.gov (United States)

    Rensing, L; Meyer-Grahle, U; Ruoff, P

    2001-05-01

    Living organisms have developed a multitude of timing mechanisms--"biological clocks." Their mechanisms are based on either oscillations (oscillatory clocks) or unidirectional processes (hourglass clocks). Oscillatory clocks comprise circatidal, circalunidian, circadian, circalunar, and circannual oscillations--which keep time with environmental periodicities--as well as ultradian oscillations, ovarian cycles, and oscillations in development and in the brain, which keep time with biological timescales. These clocks mainly determine time points at specific phases of their oscillations. Hourglass clocks are predominantly found in development and aging and also in the brain. They determine time intervals (duration). More complex timing systems combine oscillatory and hourglass mechanisms, such as the case for cell cycle, sleep initiation, or brain clocks, whereas others combine external and internal periodicities (photoperiodism, seasonal reproduction). A definition of a biological clock may be derived from its control of functions external to its own processes and its use in determining temporal order (sequences of events) or durations. Biological and chemical oscillators are characterized by positive and negative feedback (or feedforward) mechanisms. During evolution, living organisms made use of the many existing oscillations for signal transmission, movement, and pump mechanisms, as well as for clocks. Some clocks, such as the circadian clock, that time with environmental periodicities are usually compensated (stabilized) against temperature, whereas other clocks, such as the cell cycle, that keep time with an organismic timescale are not compensated. This difference may be related to the predominance of negative feedback in the first class of clocks and a predominance of positive feedback (autocatalytic amplification) in the second class. The present knowledge of a compensated clock (the circadian oscillator) and an uncompensated clock (the cell cycle), as well

  12. Knowledge Sharing

    DEFF Research Database (Denmark)

    Holdt Christensen, Peter

    The concept of knowledge management has, indeed, become a buzzword that every single organization is expected to practice and live by. Knowledge management is about managing the organization's knowledge for the common good of the organization -but practicing knowledge management is not as simple...... as that. This article focuses on knowledge sharing as the process seeking to reduce the resources spent on reinventing the wheel.The article introduces the concept of time sensitiveness; i.e. that knowledge is either urgently needed, or not that urgently needed. Furthermore, knowledge sharing...... is considered as either a push or pull system. Four strategies for sharing knowledge - help, post-it, manuals and meeting, and advice are introduced. Each strategy requires different channels for sharing knowledge. An empirical analysis in a production facility highlights how the strategies can be practiced....

  13. Parent-Child Shared Time from Middle Childhood to Late Adolescence: Developmental Course and Adjustment Correlates

    Science.gov (United States)

    Lam, Chun Bun; McHale, Susan M.; Crouter, Ann C.

    2012-01-01

    The development and adjustment correlates of parent-child social (parent, child, and others present) and dyadic time (only parent and child present) from age 8 to 18 were examined. Mothers, fathers, and firstborns and secondborns from 188 White families participated in both home and nightly phone interviews. Social time declined across…

  14. WCET analysis in shared resources real-time systems with TDMA buses

    NARCIS (Netherlands)

    Rihani, H.; Moy, M.; Maiza, C.; Altmeyer, S.

    2015-01-01

    Predictability is an important aspect in real-time and safety-critical systems, where non-functional properties -- such as the timing behavior -- have high impact on the system correctness. As many safety-critical systems have a growing performance demand, simple, but outdated architectures are not

  15. Sensory-specific clock components and memory mechanisms: investigation with parallel timing.

    Science.gov (United States)

    Gamache, Pierre-Luc; Grondin, Simon

    2010-05-01

    A challenge for researchers in the time-perception field is to determine whether temporal processing is governed by a central mechanism or by multiple mechanisms working in concert. Behavioral studies of parallel timing offer interesting insights into the question, although the conclusions fail to converge. Most of these studies focus on the number-of-clocks issue, but the commonality of memory mechanisms involved in time processing is often neglected. The present experiment aims to address a straightforward question: do signals from different modalities marking time intervals share the same clock and/or the same memory resources? To this end, an interval reproduction task involving the parallel timing of two sensory signals presented either in the same modality or in different modalities was conducted. The memory component was tested by manipulating the delay separating the presentation of the target intervals and the moment when the reproduction of one of these began. Results show that there is more variance when only visually marked intervals are presented, and this effect is exacerbated with longer retention delays. Finally, when there is only one interval to process, encoding the interval with signals delivered from two modalities helps to reduce variance. Taken together, these results suggest that the hypothesis stating that there are sensory-specific clock components and memory mechanisms is viable.

  16. Timing reproduction in teleost fish: cues and mechanisms

    Science.gov (United States)

    Juntti, Scott A; Fernald, Russell D

    2016-01-01

    Fish comprise half of extant vertebrate species and use a rich variety of reproductive strategies that have yielded insights into the basic mechanisms that evolved for sex. To maximize the chances of fertilization and survival of offspring, fish species time reproduction to occur at optimal times. For years, ethologists have performed painstaking experiments to identify sensory inputs and behavioral outputs of the brain during mating. Here we review known mechanisms that generate sexual behavior, focusing on the factors that govern the timing of these displays. The development of new technologies, including high-throughput sequencing and genome engineering, have the potential to provide novel insights into how the vertebrate brain consummates mating at the appropriate time. PMID:26952366

  17. Proper-time quantum-mechanics and the Klein paradox

    International Nuclear Information System (INIS)

    Thaller, B.

    1981-01-01

    Scattering at high potential-steps is treated in the framework of relativistic proper-time theory. No paradox arises in contrast to Dirac's wavemechanics (''Klein's paradox''); pair creation may happen with a certain probability and may be described as a scattering process with ordinary quantum-mechanical methods. (author)

  18. Experiments on microsecond conduction time plasma opening switch mechanisms

    International Nuclear Information System (INIS)

    Rix, W.; Coleman, M.; Miller, A.R.; Parks, D.; Robertson, K.; Thompson, J.; Waisman, E.; Wilson, A.

    1993-01-01

    The authors describe a series of experiments carried out on ACE 2 and ACE 4 to elucidate the mechanisms controlling the conduction and opening phases on plasma opening switches in a radial geometry with conduction times on the order of a microsecond. The results indicate both conduction and opening physics are similar to that observed on lower current systems in a coaxial geometry

  19. Time-varying properties of renal autoregulatory mechanisms

    DEFF Research Database (Denmark)

    Zou, Rui; Cupples, Will A; Yip, K P

    2002-01-01

    In order to assess the possible time-varying properties of renal autoregulation, time-frequency and time-scaling methods were applied to renal blood flow under broad-band forced arterial blood pressure fluctuations and single-nephron renal blood flow with spontaneous oscillations obtained from...... normotensive (Sprague-Dawley, Wistar, and Long-Evans) rats, and spontaneously hypertensive rats. Time-frequency analyses of normotensive and hypertensive blood flow data obtained from either the whole kidney or the single-nephron show that indeed both the myogenic and tubuloglomerular feedback (TGF) mechanisms...... have time-varying characteristics. Furthermore, we utilized the Renyi entropy to measure the complexity of blood-flow dynamics in the time-frequency plane in an effort to discern differences between normotensive and hypertensive recordings. We found a clear difference in Renyi entropy between...

  20. KETERAMPILAN METAKOGNITIF DAN HASIL BELAJAR KOGNITIF SISWA DENGAN PEMBELAJARAN READING CONCEPT MAP-TIMED PAIR SHARE (REMAP-TMPS

    Directory of Open Access Journals (Sweden)

    Fatia Rosyida

    2016-04-01

    Tujuan penelitian ini adalah untuk mengetahui pengaruh pembelajaran Reading-Concept Map-Timed Pair Share (Remap-TmPS terhadap keterampilan metakognitif dan hasil belajar kognitif. Jenis penelitian ini adalah eksperimen semu dengan desain penelitian Pretes-Postest Nonequivalent Control Group Design. Sampel penelitian ini adalah kelas X MIA 2 dan X MIA 3 di SMAN 2 Batu. Data keterampilan metakognitif  dan hasil belajar kognitif diperoleh dari tes essay. Data tersebut dianalisis mengunakan uji anacova. Hasil penelitian menunjukkan pembelajaran biologi berbasis Remap-TmPS berpengaruh terhadap keterampilan metakognitif dan hasil belajar kognitif siswa.

  1. Conception and production of a time sharing system for a Mitra-15 CII mini-computer dedicated to APL

    International Nuclear Information System (INIS)

    Perrin, Rene

    1977-01-01

    The installation of a time-sharing system on a mini-computer poses several interesting problems. These technical problems are especially interesting when the goal is to equitably divide the physical resources of the machine amongst users of a high level, conservational language like APL. Original solutions were necessary to be able to retain the rapidity and performances of the original hard and software. The system has been implemented in such way that several users may simultaneously access logical resources, such as the library zones their read/write requests are managed by semaphores which may also be directly controlled by the APL programmer. (author) [fr

  2. [Part-time medical specialist training; experiences with job-sharing for trainee internists

    NARCIS (Netherlands)

    Bevers, K.; Nauta, S.; Stuyt, P.M.J.

    2004-01-01

    Due to various factors such as social changes, an increasing number of couples with two incomes, and a growing proportion of female doctors, there has been a growing demand for part-time work in recent years. This is also true for resident physicians. Objections such as a discontinuity in care and

  3. Student understanding of time dependence in quantum mechanics

    Directory of Open Access Journals (Sweden)

    Paul J. Emigh

    2015-09-01

    Full Text Available [This paper is part of the Focused Collection on Upper Division Physics Courses.] The time evolution of quantum states is arguably one of the more difficult ideas in quantum mechanics. In this article, we report on results from an investigation of student understanding of this topic after lecture instruction. We demonstrate specific problems that students have in applying time dependence to quantum systems and in recognizing the key role of the energy eigenbasis in determining the time dependence of wave functions. Through analysis of student responses to a set of four interrelated tasks, we categorize some of the difficulties that underlie common errors. The conceptual and reasoning difficulties that have been identified are illustrated through student responses to four sets of questions administered at different points in a junior-level course on quantum mechanics. Evidence is also given that the problems persist throughout undergraduate instruction and into the graduate level.

  4. Time to rethink the neural mechanisms of learning and memory.

    Science.gov (United States)

    Gallistel, Charles R; Balsam, Peter D

    2014-02-01

    Most studies in the neurobiology of learning assume that the underlying learning process is a pairing - dependent change in synaptic strength that requires repeated experience of events presented in close temporal contiguity. However, much learning is rapid and does not depend on temporal contiguity, which has never been precisely defined. These points are well illustrated by studies showing that the temporal relations between events are rapidly learned- even over long delays- and that this knowledge governs the form and timing of behavior. The speed with which anticipatory responses emerge in conditioning paradigms is determined by the information that cues provide about the timing of rewards. The challenge for understanding the neurobiology of learning is to understand the mechanisms in the nervous system that encode information from even a single experience, the nature of the memory mechanisms that can encode quantities such as time, and how the brain can flexibly perform computations based on this information. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Soft Time-Suboptimal Controlling Structure for Mechanical Systems

    DEFF Research Database (Denmark)

    Kulczycki, Piotr; Wisniewski, Rafal; Kowalski, Piotr

    2004-01-01

    The paper presents conception of a soft control structure based on the time-optimal approach. Its parameters are selected in accordance with the rules of the statistical decision theory and additionally it allows to eliminate rapid changes in control values. The object is a basic mechanical system......, with uncertain (also non-stationary) mass treated as a stochastic process. The methodology proposed here is of a universal nature and may easily be applied with respect to other uncertainty elements of timeoptimal controlled mechanical systems....

  6. Joint accurate time and stable frequency distribution infrastructure sharing fiber footprint with research network

    Czech Academy of Sciences Publication Activity Database

    Vojtěch, J.; Šlapák, M.; Škoda, P.; Radil, J.; Havliš, O.; Altmann, M.; Münster, P.; Velč, R.; Kundrát, J.; Altmannová, L.; Vohnout, R.; Horváth, T.; Hůla, M.; Smotlacha, V.; Čížek, Martin; Pravdová, Lenka; Řeřucha, Šimon; Hrabina, Jan; Číp, Ondřej

    2017-01-01

    Roč. 56, č. 2 (2017), s. 1-7, č. článku 027101. ISSN 0091-3286 R&D Projects: GA ČR GB14-36681G Institutional support: RVO:68081731 Keywords : accurate time * stable frequency * wavelength division multiplexing * bidirectional reciprocal path * Sagnac effect Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 1.082, year: 2016

  7. The problem of time quantum mechanics versus general relativity

    CERN Document Server

    Anderson, Edward

    2017-01-01

    This book is a treatise on time and on background independence in physics. It first considers how time is conceived of in each accepted paradigm of physics: Newtonian, special relativity, quantum mechanics (QM) and general relativity (GR). Substantial differences are moreover uncovered between what is meant by time in QM and in GR. These differences jointly source the Problem of Time: Nine interlinked facets which arise upon attempting concurrent treatment of the QM and GR paradigms, as is required in particular for a background independent theory of quantum gravity. A sizeable proportion of current quantum gravity programs - e.g. geometrodynamical and loop quantum gravity approaches to quantum GR, quantum cosmology, supergravity and M-theory - are background independent in this sense. This book's foundational topic is thus furthermore of practical relevance in the ongoing development of quantum gravity programs. This book shows moreover that eight of the nine facets of the Problem of Time already occur upon ...

  8. Quantum mechanics of time travel through post-selected teleportation

    International Nuclear Information System (INIS)

    Lloyd, Seth; Garcia-Patron, Raul; Maccone, Lorenzo; Giovannetti, Vittorio; Shikano, Yutaka

    2011-01-01

    This paper discusses the quantum mechanics of closed-timelike curves (CTCs) and of other potential methods for time travel. We analyze a specific proposal for such quantum time travel, the quantum description of CTCs based on post-selected teleportation (P-CTCs). We compare the theory of P-CTCs to previously proposed quantum theories of time travel: the theory is inequivalent to Deutsch's theory of CTCs, but it is consistent with path-integral approaches (which are the best suited for analyzing quantum-field theory in curved space-time). We derive the dynamical equations that a chronology-respecting system interacting with a CTC will experience. We discuss the possibility of time travel in the absence of general-relativistic closed-timelike curves, and investigate the implications of P-CTCs for enhancing the power of computation.

  9. Recent improvements in the performance of the muiltitasked TORT on time-shared Cray computers

    International Nuclear Information System (INIS)

    Azmy, Y.Y.

    1996-01-01

    Coarse-grained angular domain decomposition of the mesh sweep algorithm has been implemented in ORNL's three dimensional transport code TORT for Cray's macrotasking environment on platforms running the UNICOS operating system. A performance model constructed earlier is reviewed and its main result, namely the identification of the sources of parallelization overhead, is used to motivate the present work. The sources of overhead treated here are: redundant operations in the angular loop across participating tasks; repetitive task creation; lock utilization to prevent overwriting the flux moment arrays accumulated by the participating tasks. Substantial reduction in the parallelization overhead is demonstrated via sample runs with fixed tunning, i.e. zero CPU hold time. Up to 50% improvement in the wall clock speedup over the previous implementation with autotunning is observed in some test problems

  10. Collisionless Weibel shocks: Full formation mechanism and timing

    Energy Technology Data Exchange (ETDEWEB)

    Bret, A. [ETSI Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Instituto de Investigaciones Energéticas y Aplicaciones Industriales, Campus Universitario de Ciudad Real, 13071 Ciudad Real (Spain); Stockem, A. [GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon (Portugal); Institut für Theoretische Physik, Lehrstuhl IV: Weltraum- und Astrophysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Narayan, R. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51 Cambridge, Massachusetts 02138 (United States); Silva, L. O. [GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon (Portugal)

    2014-07-15

    Collisionless shocks in plasmas play an important role in space physics (Earth's bow shock) and astrophysics (supernova remnants, relativistic jets, gamma-ray bursts, high energy cosmic rays). While the formation of a fluid shock through the steepening of a large amplitude sound wave has been understood for long, there is currently no detailed picture of the mechanism responsible for the formation of a collisionless shock. We unravel the physical mechanism at work and show that an electromagnetic Weibel shock always forms when two relativistic collisionless, initially unmagnetized, plasma shells encounter. The predicted shock formation time is in good agreement with 2D and 3D particle-in-cell simulations of counterstreaming pair plasmas. By predicting the shock formation time, experimental setups aiming at producing such shocks can be optimised to favourable conditions.

  11. Individuation in Quantum Mechanics and Space-Time

    Science.gov (United States)

    Jaeger, Gregg

    2010-10-01

    Two physical approaches—as distinct, under the classification of Mittelstaedt, from formal approaches—to the problem of individuation of quantum objects are considered, one formulated in spatiotemporal terms and one in quantum mechanical terms. The spatiotemporal approach itself has two forms: one attributed to Einstein and based on the ontology of space-time points, and the other proposed by Howard and based on intersections of world lines. The quantum mechanical approach is also provided here in two forms, one based on interference and another based on a new Quantum Principle of Individuation (QPI). It is argued that the space-time approach to individuation fails and that the quantum approach offers several advantages over it, including consistency with Leibniz’s Principle of Identity of Indiscernibles.

  12. A Standard for Sharing and Accessing Time Series Data: The Heliophysics Application Programmers Interface (HAPI) Specification

    Science.gov (United States)

    Vandegriff, J. D.; King, T. A.; Weigel, R. S.; Faden, J.; Roberts, D. A.; Harris, B. T.; Lal, N.; Boardsen, S. A.; Candey, R. M.; Lindholm, D. M.

    2017-12-01

    We present the Heliophysics Application Programmers Interface (HAPI), a new interface specification that both large and small data centers can use to expose time series data holdings in a standard way. HAPI was inspired by the similarity of existing services at many Heliophysics data centers, and these data centers have collaborated to define a single interface that captures best practices and represents what everyone considers the essential, lowest common denominator for basic data access. This low level access can serve as infrastructure to support greatly enhanced interoperability among analysis tools, with the goal being simplified analysis and comparison of data from any instrument, model, mission or data center. The three main services a HAPI server must perform are 1. list a catalog of datasets (one unique ID per dataset), 2. describe the content of one dataset (JSON metadata), and 3. retrieve numerical content for one dataset (stream the actual data). HAPI defines both the format of the query to the server, and the response from the server. The metadata is lightweight, focusing on use rather than discovery, and the data format is a streaming one, with Comma Separated Values (CSV) being required and binary or JSON streaming being optional. The HAPI specification is available at GitHub, where projects are also underway to develop reference implementation servers that data providers can adapt and use at their own sites. Also in the works are data analysis clients in multiple languages (IDL, Python, Matlab, and Java). Institutions which have agreed to adopt HAPI include Goddard (CDAWeb for data and CCMC for models), LASP at the University of Colorado Boulder, the Particles and Plasma Interactions node of the Planetary Data System (PPI/PDS) at UCLA, the Plasma Wave Group at the University of Iowa, the Space Sector at the Johns Hopkins Applied Physics Lab (APL), and the tsds.org site maintained at George Mason University. Over the next year, the adoption of a

  13. On the problem of time in quantum mechanics

    Science.gov (United States)

    Bauer, M.

    2017-05-01

    The problem of time in quantum mechanics (QM) concerns the fact that in the Schrödinger equation time is a parameter, not an operator. Pauli's objection to a time-energy uncertainty relation analogue to the position-momentum one, conjectured by Heisenberg early on, seemed to exclude the existence of such an operator. However Dirac's formulation of an electron's relativistic QM does allow the introduction of a dynamical time operator that is self-adjoint. Consequently, it can be considered as the generator of a unitary transformation of the system, as well as an additional system observable subject to uncertainty. In the present paper these aspects are examined within the standard framework of relativistic QM.

  14. Does a kidney-sharing alliance have to sacrifice cold ischemic time for better HLA matching?

    Science.gov (United States)

    Oniscu, Gabriel C; Plant, William; Pocock, Phil; Forsythe, John L R

    2002-05-27

    The Scotland-Northern Ireland Kidney Allocation Alliance was created in August 1998. The purpose was to optimize the transplant service through increased regional exchange, higher quality matched kidneys, and better organ distribution. An analysis was performed on prospectively collected data regarding retrieval and transplant activity. The degree of HLA matching, the cold ischemic time (CIT), the balance of exchange, and graft survival were analyzed for a 2-year period after the introduction of the new alliance and compared with the last year before alliance. There was a 17.7% increase in the number of transplants performed. In the 2-year period, 78% of kidneys were exported from the retrieving center compared with 55% in the prealliance year, (Pexchanged within the Alliance (P>0.05, Student's t test). The largest center was a net importer of kidneys, whereas small and medium-sized centers balanced their exchange within the 2-year period. The 1-year transplant survival rate improved from 81.5% in the prealliance year to 88.4% at the end of the second year. The introduction of a regional kidney allocation alliance has improved the degree of HLA matching and increased the exchange of organs, without a significant increase in the CIT and any detrimental effect on graft survival.

  15. Time Sharing Between Robotics and Process Control: Validating a Model of Attention Switching.

    Science.gov (United States)

    Wickens, Christopher Dow; Gutzwiller, Robert S; Vieane, Alex; Clegg, Benjamin A; Sebok, Angelia; Janes, Jess

    2016-03-01

    The aim of this study was to validate the strategic task overload management (STOM) model that predicts task switching when concurrence is impossible. The STOM model predicts that in overload, tasks will be switched to, to the extent that they are attractive on task attributes of high priority, interest, and salience and low difficulty. But more-difficult tasks are less likely to be switched away from once they are being performed. In Experiment 1, participants performed four tasks of the Multi-Attribute Task Battery and provided task-switching data to inform the role of difficulty and priority. In Experiment 2, participants concurrently performed an environmental control task and a robotic arm simulation. Workload was varied by automation of arm movement and both the phases of environmental control and existence of decision support for fault management. Attention to the two tasks was measured using a head tracker. Experiment 1 revealed the lack of influence of task priority and confirmed the differing roles of task difficulty. In Experiment 2, the percentage attention allocation across the eight conditions was predicted by the STOM model when participants rated the four attributes. Model predictions were compared against empirical data and accounted for over 95% of variance in task allocation. More-difficult tasks were performed longer than easier tasks. Task priority does not influence allocation. The multiattribute decision model provided a good fit to the data. The STOM model is useful for predicting cognitive tunneling given that human-in-the-loop simulation is time-consuming and expensive. © 2016, Human Factors and Ergonomics Society.

  16. The impact of public transportation strikes on use of a bicycle share program in London: interrupted time series design.

    Science.gov (United States)

    Fuller, Daniel; Sahlqvist, Shannon; Cummins, Steven; Ogilvie, David

    2012-01-01

    To investigate the immediate and sustained effects of two London Underground strikes on use of a public bicycle share program. An interrupted time series design was used to examine the impact of two 24 hour strikes on the total number of trips per day and mean trip duration per day on the London public bicycle share program. The strikes occurred on September 6th and October 4th 2010 and limited service on the London Underground. The mean total number of trips per day over the whole study period was 14,699 (SD=5390) while the mean trip duration was 18.5 minutes (SD=3.7). Significant increases in daily trip count were observed following strike 1 (3864: 95% CI 125 to 7604) and strike 2 (11,293: 95% CI 5169 to 17,416). Events that greatly constrain the primary motorised mode of transportation for a population may have unintended short-term effects on travel behaviour. These findings suggest that limiting transportation options may have the potential to increase population levels of physical activity by promoting the use of cycling. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Shared Contract-Obedient Endpoints

    Directory of Open Access Journals (Sweden)

    Étienne Lozes

    2012-12-01

    Full Text Available Most of the existing verification techniques for message-passing programs suppose either that channel endpoints are used in a linear fashion, where at most one thread may send or receive from an endpoint at any given time, or that endpoints may be used arbitrarily by any number of threads. The former approach usually forbids the sharing of channels while the latter limits what is provable about programs. In this paper we propose a midpoint between these techniques by extending a proof system based on separation logic to allow sharing of endpoints. We identify two independent mechanisms for supporting sharing: an extension of fractional shares to endpoints, and a new technique based on what we call reflexive ownership transfer. We demonstrate on a number of examples that a linear treatment of sharing is possible.

  18. Real-time sharing and expression of migraine headache suffering on Twitter: a cross-sectional infodemiology study.

    Science.gov (United States)

    Nascimento, Thiago D; DosSantos, Marcos F; Danciu, Theodora; DeBoer, Misty; van Holsbeeck, Hendrik; Lucas, Sarah R; Aiello, Christine; Khatib, Leen; Bender, MaryCatherine A; Zubieta, Jon-Kar; DaSilva, Alexandre F

    2014-04-03

    Although population studies have greatly improved our understanding of migraine, they have relied on retrospective self-reports that are subject to memory error and experimenter-induced bias. Furthermore, these studies also lack specifics from the actual time that attacks were occurring, and how patients express and share their ongoing suffering. As technology and language constantly evolve, so does the way we share our suffering. We sought to evaluate the infodemiology of self-reported migraine headache suffering on Twitter. Trained observers in an academic setting categorized the meaning of every single "migraine" tweet posted during seven consecutive days. The main outcome measures were prevalence, life-style impact, linguistic, and timeline of actual self-reported migraine headache suffering on Twitter. From a total of 21,741 migraine tweets collected, only 64.52% (14,028/21,741 collected tweets) were from users reporting their migraine headache attacks in real-time. The remainder of the posts were commercial, re-tweets, general discussion or third person's migraine, and metaphor. The gender distribution available for the actual migraine posts was 73.47% female (10,306/14,028), 17.40% males (2441/14,028), and 0.01% transgendered (2/14,028). The personal impact of migraine headache was immediate on mood (43.91%, 6159/14,028), productivity at work (3.46%, 486/14,028), social life (3.45%, 484/14,028), and school (2.78%, 390/14,028). The most common migraine descriptor was "Worst" (14.59%, 201/1378) and profanity, the "F-word" (5.3%, 73/1378). The majority of postings occurred in the United States (58.28%, 3413/5856), peaking on weekdays at 10:00h and then gradually again at 22:00h; the weekend had a later morning peak. Twitter proved to be a powerful source of knowledge for migraine research. The data in this study overlap large-scale epidemiological studies, avoiding memory bias and experimenter-induced error. Furthermore, linguistics of ongoing migraine reports

  19. Time as an Observable in Nonrelativistic Quantum Mechanics

    Science.gov (United States)

    Hahne, G. E.

    2003-01-01

    The argument follows from the viewpoint that quantum mechanics is taken not in the usual form involving vectors and linear operators in Hilbert spaces, but as a boundary value problem for a special class of partial differential equations-in the present work, the nonrelativistic Schrodinger equation for motion of a structureless particle in four- dimensional space-time in the presence of a potential energy distribution that can be time-as well as space-dependent. The domain of interest is taken to be one of two semi-infinite boxes, one bounded by two t=constant planes and the other by two t=constant planes. Each gives rise to a characteristic boundary value problem: one in which the initial, input values on one t=constant wall are given, with zero asymptotic wavefunction values in all spatial directions, the output being the values on the second t=constant wall; the second with certain input values given on both z=constant walls, with zero asymptotic values in all directions involving time and the other spatial coordinates, the output being the complementary values on the z=constant walls. The first problem corresponds to ordinary quantum mechanics; the second, to a fully time-dependent version of a problem normally considered only for the steady state (time-independent Schrodinger equation). The second problem is formulated in detail. A conserved indefinite metric is associated with space-like propagation, where the sign of the norm of a unidirectional state corresponds to its spatial direction of travel.

  20. Noether symmetries and integrability in time-dependent Hamiltonian mechanics

    Directory of Open Access Journals (Sweden)

    Jovanović Božidar

    2016-01-01

    Full Text Available We consider Noether symmetries within Hamiltonian setting as transformations that preserve Poincaré-Cartan form, i.e., as symmetries of characteristic line bundles of nondegenerate 1-forms. In the case when the Poincaré-Cartan form is contact, the explicit expression for the symmetries in the inverse Noether theorem is given. As examples, we consider natural mechanical systems, in particular the Kepler problem. Finally, we prove a variant of the theorem on complete (non-commutative integrability in terms of Noether symmetries of time-dependent Hamiltonian systems.

  1. Collecting response times using Amazon Mechanical Turk and Adobe Flash.

    Science.gov (United States)

    Simcox, Travis; Fiez, Julie A

    2014-03-01

    Crowdsourcing systems like Amazon's Mechanical Turk (AMT) allow data to be collected from a large sample of people in a short amount of time. This use has garnered considerable interest from behavioral scientists. So far, most experiments conducted on AMT have focused on survey-type instruments because of difficulties inherent in running many experimental paradigms over the Internet. This study investigated the viability of presenting stimuli and collecting response times using Adobe Flash to run ActionScript 3 code in conjunction with AMT. First, the timing properties of Adobe Flash were investigated using a phototransistor and two desktop computers running under several conditions mimicking those that may be present in research using AMT. This experiment revealed some strengths and weaknesses of the timing capabilities of this method. Next, a flanker task and a lexical decision task implemented in Adobe Flash were administered to participants recruited with AMT. The expected effects in these tasks were replicated. Power analyses were conducted to describe the number of participants needed to replicate these effects. A questionnaire was used to investigate previously undescribed computer use habits of 100 participants on AMT. We conclude that a Flash program in conjunction with AMT can be successfully used for running many experimental paradigms that rely on response times, although experimenters must understand the limitations of the method.

  2. Universal entrainment mechanism controls contact times with motile cells

    Science.gov (United States)

    Mathijssen, Arnold J. T. M.; Jeanneret, Raphaël; Polin, Marco

    2018-03-01

    Contact between particles and motile cells underpins a wide variety of biological processes, from nutrient capture and ligand binding to grazing, viral infection, and cell-cell communication. The window of opportunity for these interactions depends on the basic mechanism determining contact time, which is currently unknown. By combining experiments on three different species—Chlamydomonas reinhardtii, Tetraselmis subcordiforms, and Oxyrrhis marina—with simulations and analytical modeling, we show that the fundamental physical process regulating proximity to a swimming microorganism is hydrodynamic particle entrainment. The resulting distribution of contact times is derived within the framework of Taylor dispersion as a competition between advection by the cell surface and microparticle diffusion, and predicts the existence of an optimal tracer size that is also observed experimentally. Spatial organization of flagella, swimming speed, and swimmer and tracer size influence entrainment features and provide tradeoffs that may be tuned to optimize the estimated probabilities for microbial interactions like predation and infection.

  3. Shared pledge shared vision

    International Nuclear Information System (INIS)

    Boussaha, Ali; Diatta, Christian Sina

    2005-01-01

    The New Partnership for Africa's Development (NEPAD) is a pledge by African leaders to eradicate poverty and to promote sustainable growth and development. NEPAD is a 'new framework of interaction with the rest of the world, including the industrialised countries and multilateral organizations.' The agenda is based on regional priorities and development plans and its implementation relies on African ownership and management. As a UN system organisation, the IAEA strongly supports the priorities identified in the Millennium Declaration and the New Partnership for Africa's Development. As a technical agency, the IAEA shares its recognized core competencies and technical expertise in support of NEPAD goals. Efforts aim at strengthening institutional capacity building in nuclear sciences and technology and promoting the sustainable application of nuclear techniques for social and economic development. The IAEA has a membership of 34 African countries. The Agency supports them under its technical cooperation programme through provision of expertise, training opportunities and equipment in priority areas identified by the countries themselves. For many African Member States, meeting basic human needs through the implementation of poverty alleviation strategies remains the top priority on the agenda for national development plans and international cooperation programmes. In the context of sustainable development, special attention is being paid to enlarging the contribution of isotopes and nuclear techniques in major areas of economic and social significance and to promoting regional cooperation in nuclear science and technology related fields. As a partner in development, the Agency has promoted and undertaken programmes to support African countries' efforts to address priority development issues particularly in the areas of health care, food and agriculture and water resources development. The IAEA technical cooperation mechanism includes support to the African Regional

  4. Distinct timing mechanisms produce discrete and continuous movements.

    Directory of Open Access Journals (Sweden)

    Raoul Huys

    2008-04-01

    Full Text Available The differentiation of discrete and continuous movement is one of the pillars of motor behavior classification. Discrete movements have a definite beginning and end, whereas continuous movements do not have such discriminable end points. In the past decade there has been vigorous debate whether this classification implies different control processes. This debate up until the present has been empirically based. Here, we present an unambiguous non-empirical classification based on theorems in dynamical system theory that sets discrete and continuous movements apart. Through computational simulations of representative modes of each class and topological analysis of the flow in state space, we show that distinct control mechanisms underwrite discrete and fast rhythmic movements. In particular, we demonstrate that discrete movements require a time keeper while fast rhythmic movements do not. We validate our computational findings experimentally using a behavioral paradigm in which human participants performed finger flexion-extension movements at various movement paces and under different instructions. Our results demonstrate that the human motor system employs different timing control mechanisms (presumably via differential recruitment of neural subsystems to accomplish varying behavioral functions such as speed constraints.

  5. Conformal quantum mechanics and holography in noncommutative space-time

    Science.gov (United States)

    Gupta, Kumar S.; Harikumar, E.; Zuhair, N. S.

    2017-09-01

    We analyze the effects of noncommutativity in conformal quantum mechanics (CQM) using the κ-deformed space-time as a prototype. Up to the first order in the deformation parameter, the symmetry structure of the CQM algebra is preserved but the coupling in a canonical model of the CQM gets deformed. We show that the boundary conditions that ensure a unitary time evolution in the noncommutative CQM can break the scale invariance, leading to a quantum mechanical scaling anomaly. We calculate the scaling dimensions of the two and three point functions in the noncommutative CQM which are shown to be deformed. The AdS2 / CFT1 duality for the CQM suggests that the corresponding correlation functions in the holographic duals are modified. In addition, the Breitenlohner-Freedman bound also picks up a noncommutative correction. The strongly attractive regime of a canonical model of the CQM exhibit quantum instability. We show that the noncommutativity softens this singular behaviour and its implications for the corresponding holographic duals are discussed.

  6. Supersymmetric mechanics. Vol. 2. The attractor mechanism and space time singularities

    International Nuclear Information System (INIS)

    Bellucci, S.; Marrani, A.; Ferrara, S.

    2006-01-01

    This is the second volume in a series of books on the general theme of Supersymmetric Mechanics; the series is based on lectures and discussions held in 2005 and 2006 at the INFN-Laboratori Nazionali di Frascati. The first volume appears as Lect. Notes Physics, Vol. 698 ''Supersymmetric Mechanics, Vol.1: Supersymmetry, Noncommutativity and Matrix Models'' (2006) ISBN: 3-540-33313-4. The present extensive lecture supplies a pedagogical introduction, at the non-expert level, to the attractor mechanism in space-time singularities. In such a framework, supersymmetry seems to be related to dynamical systems with fixed points, describing the equilibrium state and the stability features of the thermodynamics of black holes. After a qualitative overview, explicit examples realizing the attractor mechanism are treated at some length; they include relevant cases of asymptotically flat, maximal and non-maximal, extended supergravities in 4 and 5 dimensions. A number of recent advances along various directions of research on the attractor mechanism are also given. (orig.)

  7. Incentives for Part-Time Faculty to Participate in the Shared Governance Process within the Institution of California Community Colleges (CCC)

    Science.gov (United States)

    Huyck, Kristen J.

    2012-01-01

    The involvement of part-time faculty tends to be even lower than the engagement level of full-time faculty who partake in the system of shared governance in the California Community Colleges (CCC). During a time when state funds are diminishing, there is a projection of retirement for many community college leaders (Fulton-Calkins & Milling,…

  8. Early mechanical stimulation only permits timely bone healing in sheep.

    Science.gov (United States)

    Tufekci, Pelin; Tavakoli, Aramesh; Dlaska, Constantin; Neumann, Mirjam; Shanker, Mihir; Saifzadeh, Siamak; Steck, Roland; Schuetz, Michael; Epari, Devakar

    2018-06-01

    Bone fracture healing is sensitive to the fixation stability. However, it is unclear which phases of healing are mechano-sensitive and if mechanical stimulation is required throughout repair. In this study, a novel bone defect model, which isolates an experimental fracture from functional loading, was applied in sheep to investigate if stimulation limited to the early proliferative phase is sufficient for bone healing. An active fixator controlled motion in the fracture. Animals of the control group were unstimulated. In the physiological-like group, 1 mm axial compressive movements were applied between day 5 and 21, thereafter the movements were decreased in weekly increments and stopped after 6 weeks. In the early stimulatory group, the movements were stopped after 3 weeks. The experimental fractures were evaluated with mechanical and micro-computed tomography methods after 9 weeks healing. The callus strength of the stimulated fractures (physiological-like and early stimulatory) was greater than the unstimulated control group. The control group was characterized by minimal external callus formation and a lack of bone bridging at 9 weeks. In contrast, the stimulated groups exhibited advanced healing with solid bone formation across the defect. This was confirmed quantitatively by a lower bone volume in the control group compared to the stimulated groups.The novel experimental model permits the application of a well-defined load history to an experimental bone fracture. The poor healing observed in the control group is consistent with under-stimulation. This study has shown early mechanical stimulation only is sufficient for a timely healing outcome. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1790-1796, 2018. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  9. Job Sharing Through Part Time Contracts. A Consideration in the Context of Declining School Enrolments in Ontario.

    Science.gov (United States)

    Kumar, Krishna

    Two questionnaires were sent to all school boards and a sample of teachers in Ontario to assess how receptive boards and teachers are to job sharing as an alternative work pattern in schools affected by declining enrollment. The report gives the background of the concept of job sharing and an analysis of the benefits, work situations, and problems…

  10. Temporal isolation in an HSF-enabled real-time kernel in the presence of shared resources

    NARCIS (Netherlands)

    Heuvel, van den M.M.H.P.; Bril, R.J.; Lukkien, J.J.; Parmer, G.; Gleixner, T.

    2011-01-01

    Hierarchical scheduling frameworks (HSFs) have been extensively investigated as a paradigm for facilitating temporal isolation between components that need to be integrated on a single shared processor. To support resource sharing within two-level, fixed priority scheduled HSFs, two synchronization

  11. Tailoring Shared Governance to the Needs and Opportunities of the Times. Research & Occasional Paper Series: CSHE.13.13

    Science.gov (United States)

    King, C. Judson

    2013-01-01

    Shared governance between the administration and faculty has been traditional for most public universities, but varies considerably in its nature and effectiveness. In the United States it probably takes its most structured form at the University of California. There are good reasons for having shared governance, and yet it tends to be poorly…

  12. Overcoming misconceptions in quantum mechanics with the time evolution operator

    International Nuclear Information System (INIS)

    Garcia Quijas, P C; Arevalo Aguilar, L M

    2007-01-01

    Recently, there have been many efforts to use the research techniques developed in the field of physics education research to improve the teaching and learning of quantum mechanics. In particular, part of this research is focusing on misconceptions held by students. For instance, a set of misconceptions is associated with the concept of stationary states. In this paper, we argue that a possible way to remove these is to solve the Schroedinger equation using the evolution operator method (EOM), and stress the fact that to find stationary states is only the first step in solving that equation. The EOM consists in solving the Schroedinger equation by direct integration, i.e. Ψ(x, t) = U(t)Ψ(x, 0), where U(t)=e -itH-hat/h is the time evolution operator, and Ψ(x, 0) is the initial state. We apply the evolution operator method in the case of the harmonic oscillator

  13. Incentive mechanism based on cooperative advertising for cost information sharing in a supply chain with competing retailers

    Science.gov (United States)

    Setak, Mostafa; Kafshian Ahar, Hajar; Alaei, Saeed

    2017-09-01

    This paper proposes a new motivation for information sharing in a decentralized channel consisting of a single manufacturer and two competing retailers. The manufacturer provides a common product to the retailers at the same wholesale price. Both retailers add their own values to the product and distribute it to consumers. Factors such as retail prices, values added to the product, and local advertising of the retailers simultaneously have effect on market demand. Each retailer has full information about the own added value which is unknown to the manufacturer and other retailer. The manufacturer uses a cooperative advertising program for motivating the retailers to disclose their private information. A numerical study is presented to compare different scenarios of information sharing. Computational results show that there is a condition in which full information sharing is beneficial for all members of the supply chain through cooperative advertising program and, therefore, retailers have enough incentive to disclose their cost information to the manufacturer.

  14. The influence of business conditions on supply chain information-sharing mechanisms : A study among supply chain links of SMEs

    NARCIS (Netherlands)

    Welker, Gera A.; van der Vaart, Taco; van Donk, Dirk Pieter

    The literature acknowledges that the type and the level of supply chain integration differ in various situations. This paper investigates the influence of business conditions on internal and external information sharing and the role of ICT in order processing, using a multi-case study among SMEs.

  15. Increasing Power by Sharing Information from Genetic Background and Treatment in Clustering of Gene Expression Time Series

    Directory of Open Access Journals (Sweden)

    Sura Zaki Alrashid

    2018-02-01

    Full Text Available Clustering of gene expression time series gives insight into which genes may be co-regulated, allowing us to discern the activity of pathways in a given microarray experiment. Of particular interest is how a given group of genes varies with different conditions or genetic background. This paper develops
a new clustering method that allows each cluster to be parameterised according to whether the behaviour of the genes across conditions is correlated or anti-correlated. By specifying correlation between such genes,more information is gain within the cluster about how the genes interrelate. Amyotrophic lateral sclerosis (ALS is an irreversible neurodegenerative disorder that kills the motor neurons and results in death within 2 to 3 years from the symptom onset. Speed of progression for different patients are heterogeneous with significant variability. The SOD1G93A transgenic mice from different backgrounds (129Sv and C57 showed consistent phenotypic differences for disease progression. A hierarchy of Gaussian isused processes to model condition-specific and gene-specific temporal co-variances. This study demonstrated about finding some significant gene expression profiles and clusters of associated or co-regulated gene expressions together from four groups of data (SOD1G93A and Ntg from 129Sv and C57 backgrounds. Our study shows the effectiveness of sharing information between replicates and different model conditions when modelling gene expression time series. Further gene enrichment score analysis and ontology pathway analysis of some specified clusters for a particular group may lead toward identifying features underlying the differential speed of disease progression.

  16. Characterizing time-dependent mechanics in metallic MEMS

    Directory of Open Access Journals (Sweden)

    Geers M.G.D.

    2010-06-01

    Full Text Available Experiments for characterization of time-dependent material properties in free-standing metallic microelectromechanical system (MEMS pose challenges: e.g. fabrication and handling (sub-μm sized specimens, control and measurement of sub-μN loads and sub-μm displacements over long periods and various temperatures [1]. A variety of experimental setups have been reported each having their pros and cons. One example is a micro-tensile tester with an ingenious electro-static specimen gripping system [2] aiding simple specimen design giving good results at μN and sub-μm levels, but without in-situ full-field observations. Other progressive examples assimilate the specimen, MEMS actuators and load cells on a single chip [3,4] yielding significant results at nN and nm levels with in-situ TEM/SEM observability, though not without complications: complex load actuator/sensor calibration per chip, measures to reduce fabrication failure and unfeasible cofabrication on wafers with commercial metallic MEMS. This work aims to overcome these drawbacks by developing experimental methods with high sensitivity, precision and in-situ full-field observation capabilities. Moreover, these should be applicable to simple free-standing metallic MEMS that can be co-fabricated with commercial devices. These methods will then serve in systematic studies into size-effects in time-dependent material properties. First a numeric-experimental method is developed. It characterizes bending deformation of onwafer μm-sized aluminum cantilevers. A specially designed micro-clamp is used to mechanically apply a constant precise deflection of the beam (zres <50 nm for a prolonged period, see fig. 1. After this period, the deflection by the micro-clamp is removed. Full-field height maps with the ensuing deformation are measured over time with confocal optical profilometry (COP. This yields the tip deflection as function of time with ~3 nm precision, see fig.2. To extract material

  17. Attention: Reaction Time and Accuracy Reveal Different Mechanisms

    Science.gov (United States)

    Prinzmetal, William; McCool, Christin; Park, Samuel

    2005-01-01

    The authors propose that there are 2 different mechanisms whereby spatial cues capture attention. The voluntary mechanism is the strategic allocation of perceptual resources to the location most likely to contain the target. The involuntary mechanism is a reflexive orienting response that occurs even when the spatial cue does not indicate the…

  18. A Hierarchical Auction-Based Mechanism for Real-Time Resource Allocation in Cloud Robotic Systems.

    Science.gov (United States)

    Wang, Lujia; Liu, Ming; Meng, Max Q-H

    2017-02-01

    Cloud computing enables users to share computing resources on-demand. The cloud computing framework cannot be directly mapped to cloud robotic systems with ad hoc networks since cloud robotic systems have additional constraints such as limited bandwidth and dynamic structure. However, most multirobotic applications with cooperative control adopt this decentralized approach to avoid a single point of failure. Robots need to continuously update intensive data to execute tasks in a coordinated manner, which implies real-time requirements. Thus, a resource allocation strategy is required, especially in such resource-constrained environments. This paper proposes a hierarchical auction-based mechanism, namely link quality matrix (LQM) auction, which is suitable for ad hoc networks by introducing a link quality indicator. The proposed algorithm produces a fast and robust method that is accurate and scalable. It reduces both global communication and unnecessary repeated computation. The proposed method is designed for firm real-time resource retrieval for physical multirobot systems. A joint surveillance scenario empirically validates the proposed mechanism by assessing several practical metrics. The results show that the proposed LQM auction outperforms state-of-the-art algorithms for resource allocation.

  19. Elastodynamic metasurface: Depolarization of mechanical waves and time effects

    Energy Technology Data Exchange (ETDEWEB)

    Boutin, Claude, E-mail: claude.boutin@entpe.fr [Ecole Nationale des Travaux Publics de l' Etat, Université de Lyon, LGCB, UMR CNRS 5513, Vaulx-en-Velin (France); Schwan, Logan [Acoustics Research Center, University of Salford, Newton Building, Salford M5 4WT (United Kingdom); Dietz, Matthew S. [Department of Civil Engineering, University of Bristol, Queen' s Building, Bristol BS8 1TR (United Kingdom)

    2015-02-14

    We report the concept of microstructured surfaces with inner resonance in the field of elastodynamics, so-called elastodynamic metasurfaces. Such metasurfaces allow for wavefield manipulation of mechanical waves by tuning the boundary conditions at specific frequencies. In particular, they can be used to depolarize elastic waves without introducing heterogeneities in the medium itself; the physical means to do so in homogeneous elastic media used to remain, surprisingly, an open question while depolarization is commonplace in electromagnetism. The principle relies on the anisotropic behaviour of a subwavelength array of resonators: Their subwavelength configuration confines the Bragg interferences scattered by resonators into a boundary layer. The effective behaviour of the resonating array is expressed with homogenization as an unconventional impedance, the frequency-dependence, and anisotropy of which lead to depolarization and time effects. The concept of the elastodynamic metasurface is tested experimentally and results bear testament to its efficacy and robustness. Elastodynamic metasurfaces are easily realized and analytically predictable, opening new possibilities in tomography techniques, ultrasonics, geophysics, vibration control, materials and structure design.

  20. Fluctuations of the experience of togetherness within the team over time: task-cohesion and shared understanding throughout a sporting regular season.

    Science.gov (United States)

    Bourbousson, Jérôme; Fortes-Bourbousson, Marina

    2017-06-01

    Based on a diagnosis action research design, the present study assessed the fluctuations of the team experience of togetherness. Reported experiences of 12 basketball team members playing in the under-18 years old national championship were studied during a four-month training and competitive period. Time series analysis (Auto-Regressive Integrated Moving Average procedures) served to describe temporal properties of the way in which the fluctuations of task-cohesion and shared understanding were step-by-step experienced over time, respectively. Correlations, running-correlations and cross-lagged correlations were used to describe the temporal links that governed the relationships between both phenomena. The results indicated that the task-cohesion dimensions differed mainly for shared understanding dynamics in that their time fluctuations were not embedded in external events, and that the variations in shared understanding tend to precede 'individual attractions to the task' variations with seven team practical sessions. This study argues for further investigation of how 'togetherness' is experienced alternatively as a feeling of cohesion or shared understanding. Practitioner Summary: The present action research study investigated the experience that the team members have to share information during practice, and the subsequent benefices on team cohesion. Results call for specific interventions that make team members accept the fluctuating nature of team phenomena, to help them maintaining their daily efforts.

  1. Rheumatoid Arthritis-Associated Interstitial Lung Disease and Idiopathic Pulmonary Fibrosis: Shared Mechanistic and Phenotypic Traits Suggest Overlapping Disease Mechanisms.

    Science.gov (United States)

    Paulin, Francisco; Doyle, Tracy J; Fletcher, Elaine A; Ascherman, Dana P; Rosas, Ivan O

    2015-01-01

    The prevalence of clinically evident interstitial lung disease in patients with rheumatoid arthritis is approximately 10%. An additional 33% of undiagnosed patients have interstitial lung abnormalities that can be detected with high-resolution computed tomography. Rheumatoid arthritis-interstitial lung disease patients have three times the risk of death compared to those with rheumatoid arthritis occurring in the absence of interstitial lung disease, and the mortality related to interstitial lung disease is rising. Rheumatoid arthritis-interstitial lung disease is most commonly classified as the usual interstitial pneumonia pattern, overlapping mechanistically and phenotypically with idiopathic pulmonary fibrosis, but can occur in a non-usual interstitial pneumonia pattern, mainly nonspecific interstitial pneumonia. Based on this, we propose two possible pathways to explain the coexistence of rheumatoid arthritis and interstitial lung disease: (i) Rheumatoid arthritis-interstitial lung disease with a non-usual interstitial pneumonia pattern may come about when an immune response against citrullinated peptides taking place in another site (e.g. the joints) subsequently affects the lungs; (ii) Rheumatoid arthritis-interstitial lung disease with a usual interstitial pneumonia pattern may represent a disease process in which idiopathic pulmonary fibrosis-like pathology triggers an immune response against citrullinated proteins that promotes articular disease indicative of rheumatoid arthritis. More studies focused on elucidating the basic mechanisms leading to different sub-phenotypes of rheumatoid arthritis-interstitial lung disease and the overlap with idiopathic pulmonary fibrosis are necessary to improve our understanding of the disease process and to define new therapeutic targets.

  2. Complex New Product Development projects - How the Project Manager’s Information Sharing With Core Actors Changes Over Time

    DEFF Research Database (Denmark)

    Jepsen, Lisbeth Brøde

    2013-01-01

    A heavily burdened project manager must ensure effective information sharing with actors inside and outside the organization because this is a necessary condition for a new product development (NPD) project to achieve its objectives. Knowledge, however, on who actually assists a project manager...... with the information sharing during NPD projects is limited; therefore, this study of longitudinal objective email data (4658 emails) during a NPD project contributes to theory and practice by advancing our understanding of when and how the project manager establishes relationships with different core actors inside...

  3. Knowledge Sharing is Knowledge Creation

    DEFF Research Database (Denmark)

    Greve, Linda

    2015-01-01

    Knowledge sharing and knowledge transfer are important to knowledge communication. However when groups of knowledge workers engage in knowledge communication activities, it easily turns into mere mechanical information processing despite other ambitions. This article relates literature of knowledge...... communication and knowledge creation to an intervention study in a large Danish food production company. For some time a specific group of employees uttered a wish for knowledge sharing, but it never really happened. The group was observed and submitted to metaphor analysis as well as analysis of co...

  4. Time symmetry and asymmetry in quantum mechanics and quantum cosmology

    International Nuclear Information System (INIS)

    Gell-Mann, M.; Hartle, J.B.

    1992-01-01

    The disparity between the time symmetry of the fundamental laws of physics and the time asymmetries of the observed universe has been a subject of fascination for physicists since the late 19th century. It was also for Sakharov, if the authors judge correctly from his writings the following general time asymmetries are observed in this universe: The thermodynamic arrow of time --- the fact that approximately isolated systems are now almost all evolving towards equilibrium in the same direction of time. The psychological arrow of time --- we remember the past, we predict the future. The arrow of time of retarded electromagnetic radiation. The arrow of time supplied by the CP non-invariance of the weak interactions and the CPT invariance of field theory. The arrow of time of the approximately uniform expansion of the universe. The arrow of time supplied by the growth of inhomogeneity in the expanding universe

  5. 47 CFR 25.260 - Time sharing between DoD meteorological satellite systems and non-voice, non-geostationary...

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Time sharing between DoD meteorological satellite systems and non-voice, non-geostationary satellite systems in the 400.15-401 MHz band. 25.260 Section 25.260 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES...

  6. Domain-general involvement of the posterior frontolateral cortex in time-based resource-sharing in working memory: An fMRI study

    NARCIS (Netherlands)

    Vergauwe, E.; Hartstra, E.; Barrouillet, P.; Brass, M.

    2015-01-01

    Working memory is often defined in cognitive psychology as a system devoted to the simultaneous processing and maintenance of information. In line with the time-based resource-sharing model of working memory (TBRS; Barrouillet and Camos, 2015; Barrouillet et al., 2004), there is accumulating

  7. Mechanisms of time-based figure-ground segregation.

    Science.gov (United States)

    Kandil, Farid I; Fahle, Manfred

    2003-11-01

    Figure-ground segregation can rely on purely temporal information, that is, on short temporal delays between positional changes of elements in figure and ground (Kandil, F.I. & Fahle, M. (2001) Eur. J. Neurosci., 13, 2004-2008). Here, we investigate the underlying mechanisms by measuring temporal segregation thresholds for various kinds of motion cues. Segregation can rely on monocular first-order motion (based on luminance modulation) and second-order motion cues (contrast modulation) with a high temporal resolution of approximately 20 ms. The mechanism can also use isoluminant motion with a reduced temporal resolution of 60 ms. Figure-ground segregation can be achieved even at presentation frequencies too high for human subjects to inspect successive frames individually. In contrast, when stimuli are presented dichoptically, i.e. separately to both eyes, subjects are unable to perceive any segregation, irrespective of temporal frequency. We propose that segregation in these displays is detected by a mechanism consisting of at least two stages. On the first level, standard motion or flicker detectors signal local positional changes (flips). On the second level, a segregation mechanism combines the local activities of the low-level detectors with high temporal precision. Our findings suggest that the segregation mechanism can rely on monocular detectors but not on binocular mechanisms. Moreover, the results oppose the idea that segregation in these displays is achieved by motion detectors of a higher order (motion-from-motion), but favour mechanisms sensitive to short temporal delays even without activation of higher-order motion detectors.

  8. What happened to anti-malarial markets after the Affordable Medicines Facility-malaria pilot? Trends in ACT availability, price and market share from five African countries under continuation of the private sector co-payment mechanism.

    Science.gov (United States)

    Tougher, Sarah; Hanson, Kara; Goodman, Catherine

    2017-04-25

    The private sector supplies anti-malarial treatment for large proportions of patients in sub-Saharan Africa. Following the large-scale piloting of the Affordable Medicines Facility-malaria (AMFm) from 2010 to 2011, a private sector co-payment mechanism (CPM) provided continuation of private sector subsidies for quality-assured artemisinin combination therapies (QAACT). This article analyses for the first time the extent to which improvements in private sector QAACT supply and distribution observed during the AMFm were maintained or intensified during continuation of the CPM through 2015 in Kenya, Madagascar, Nigeria, Tanzania and Uganda using repeat cross-sectional outlet survey data. QAACT market share in all five countries increased during the AMFm period (p private sector QAACT availability were maintained or improved. In 2014/15, private sector QAACT availability was greater than 70% in Nigeria (84.3%), Kenya (70.5%), Tanzania (83.0%) and Uganda (77.1%), but only 11.2% in Madagascar. QAACT market share was maintained or improved post-AMFm in Nigeria, Tanzania and Uganda, but statistically significant declines were observed in Kenya and Madagascar. In 2014/5, QAACT market share was highest in Kenya and Uganda (48.2 and 47.5%, respectively) followed by Tanzania (39.2%), Nigeria (35.0%), and Madagascar (7.0%). Four of the five countries experienced significant decreases in median QAACT price during the AMFm period. Private sector QAACT prices were maintained or further reduced in Tanzania, Nigeria and Uganda, but prices increased significantly in Kenya and Madagascar. SP prices were consistently lower than those of QAACT in the AMFm period, with the exception of Kenya and Tanzania in 2011, where they were equal. In 2014/5 QAACT remained two to three times more expensive than the most popular non-artemisinin therapy in all countries except Tanzania. Results suggest that a private sector co-payment mechanism for QAACT implemented at national scale for 5 years was

  9. Sharing family and household:

    DEFF Research Database (Denmark)

    Winther, Ida Wentzel

    Keynote: Family relationships are normatively assumed to be characterized by ‘sharing’, such as living together in the same home, occupying the same place, sharing stuff, blood and biology, spending special and ordinary time together, and consequently creating shared biographical experiences....... In that way, families are thrown into togetherness. At the same time, we see families in varying forms where 'sharing' is lived and contested differently. In Denmark, many children live in nuclear families, and many live in different variations of more than one household. For those who share household...... and family, 'sharing' will be a basic condition. No matter what, they should share life circumstances, more stories, more places and spaces, more households families with both kin and non-kin. This keynote addresses the particular of children’s experiences of living apart and/or living together in sharing...

  10. Time-dependent problems in quantum-mechanical state reconstruction

    International Nuclear Information System (INIS)

    Leonhardt, U.; Bardroff, P. J.

    1997-01-01

    We study the state reconstruction of wave packets that travel in time-dependent potentials. We solve the problem for explicitly time-dependent potentials. We solve the problem for explicitly time-dependent harmonic oscillators and sketch a general adaptive technique for finding the wave function that matches and observed evolution. (authors)

  11. View-sharing in keyhole imaging: Partially compressed central k-space acquisition in time-resolved MRA at 3.0 T

    Energy Technology Data Exchange (ETDEWEB)

    Hadizadeh, Dariusch R., E-mail: Dariusch.Hadizadeh@ukb.uni-bonn.de [University of Bonn, Department of Radiology, Sigmund-Freud-Strasse 25, 53127 Bonn (Germany); Gieseke, Juergen [University of Bonn, Department of Radiology, Sigmund-Freud-Strasse 25, 53127 Bonn (Germany); Philips Healthcare, Best (Netherlands); Beck, Gabriele; Geerts, Liesbeth [Philips Healthcare, Best (Netherlands); Kukuk, Guido M. [University of Bonn, Department of Radiology, Sigmund-Freud-Strasse 25, 53127 Bonn (Germany); Bostroem, Azize [Department of Neurosurgery, Sigmund-Freud-Strasse 25, 53127 Bonn, Deutschland (Germany); Urbach, Horst; Schild, Hans H.; Willinek, Winfried A. [University of Bonn, Department of Radiology, Sigmund-Freud-Strasse 25, 53127 Bonn (Germany)

    2011-11-15

    Introduction: Time-resolved contrast-enhanced magnetic resonance (MR) angiography (CEMRA) of the intracranial vasculature has proved its clinical value for the evaluation of cerebral vascular disease in cases where both flow hemodynamics and morphology are important. The purpose of this study was to evaluate a combination of view-sharing with keyhole imaging to increase spatial and temporal resolution of time-resolved CEMRA at 3.0 T. Methods: Alternating view-sharing was combined with randomly segmented k-space ordering, keyhole imaging, partial Fourier and parallel imaging (4DkvsMRA). 4DkvsMRA was evaluated using varying compression factors (80-100) resulting in spatial resolutions ranging from (1.1 x 1.1 x 1.4) to (0.96 x 0.96 x 0.95) mm{sup 3} and temporal resolutions ranging from 586 ms/dynamic scan - 288 ms/dynamic scan in three protocols in 10 healthy volunteers and seven patients (17 subjects). DSA correlation was available in four patients with cerebral arteriovenous malformations (cAVMs) and one patient with cerebral teleangiectasia. Results: 4DkvsMRA was successfully performed in all subjects and showed clear depiction of arterial and venous phases with diagnostic image quality. At the maximum view-sharing compression factor (=100), a 'flickering' artefact was observed. Conclusion: View-sharing in keyhole imaging allows for increased spatial and temporal resolution in time-resolved MRA.

  12. View-sharing in keyhole imaging: Partially compressed central k-space acquisition in time-resolved MRA at 3.0 T

    International Nuclear Information System (INIS)

    Hadizadeh, Dariusch R.; Gieseke, Juergen; Beck, Gabriele; Geerts, Liesbeth; Kukuk, Guido M.; Bostroem, Azize; Urbach, Horst; Schild, Hans H.; Willinek, Winfried A.

    2011-01-01

    Introduction: Time-resolved contrast-enhanced magnetic resonance (MR) angiography (CEMRA) of the intracranial vasculature has proved its clinical value for the evaluation of cerebral vascular disease in cases where both flow hemodynamics and morphology are important. The purpose of this study was to evaluate a combination of view-sharing with keyhole imaging to increase spatial and temporal resolution of time-resolved CEMRA at 3.0 T. Methods: Alternating view-sharing was combined with randomly segmented k-space ordering, keyhole imaging, partial Fourier and parallel imaging (4DkvsMRA). 4DkvsMRA was evaluated using varying compression factors (80-100) resulting in spatial resolutions ranging from (1.1 x 1.1 x 1.4) to (0.96 x 0.96 x 0.95) mm 3 and temporal resolutions ranging from 586 ms/dynamic scan - 288 ms/dynamic scan in three protocols in 10 healthy volunteers and seven patients (17 subjects). DSA correlation was available in four patients with cerebral arteriovenous malformations (cAVMs) and one patient with cerebral teleangiectasia. Results: 4DkvsMRA was successfully performed in all subjects and showed clear depiction of arterial and venous phases with diagnostic image quality. At the maximum view-sharing compression factor (=100), a 'flickering' artefact was observed. Conclusion: View-sharing in keyhole imaging allows for increased spatial and temporal resolution in time-resolved MRA.

  13. Principle for possible memory structures with extra high density by using the electron sharing mechanisms of atoms in an inflective orbit

    Science.gov (United States)

    Sengor, T.

    2014-10-01

    Both of the qualitative and quantitative knowledge of electromagnetic fields in the inter-atomic scale bring useful applications. From this point of view, bringing some possible new sights and solutions to atom-electron-photon-atom and/or molecule interactions is aimed in the near-field at inter atomic scale and their potential applications. The electron sharing processes between neighbor atoms are considered as an inflective surface system and an inflective guiding processes. The critical pass and transition structures are derived. The structures involving trigging that transition mechanisms may be suitable to design extra high density and fast data storage processes. The electron sharing processes between two near atomic system are modelled with gate mechanisms involving two distinct passages: continuous pass and discontinuous pass. Even if the stochastic processes are applicable at these cases theoretical approach putting an influence like inner and external dipole mechanisms fits best to the situation and provides almost deterministic scheme, which has potential to estimate some processes being able to design new electronics structures and devices. We call orbitron all of such structures and/or devices. The boundary value problem of atomic system sharing an electron in the way of electron passage model is formulated in inflective spherical coordinate system. The wave phenomenon is studied near spherically inflection points. The analytical essentials are derived for the solution of Helmholtz's equation when inflective boundaries are included. The evaluation is obtained by the extracted separation method. The results are given by using the spherically inflective wave series. The method is reshaped for the solution of Schrödinger equation.

  14. Timing Is Everything: Corticothalamic Mechanisms for Active Listening.

    Science.gov (United States)

    Linden, Jennifer F

    2017-07-05

    In this issue of Neuron, Guo et al. (2017) describe a layer 6 corticothalamic circuit that alternately drives cortical states favoring either sensory detection or discrimination. They also identify a neural mechanism that resets the phase of low-frequency cortical oscillations. Copyright © 2017. Published by Elsevier Inc.

  15. Time dependent mechanical modeling for polymers based on network theory

    Energy Technology Data Exchange (ETDEWEB)

    Billon, Noëlle [MINES ParisTech, PSL-Research University, CEMEF – Centre de mise en forme des matériaux, CNRS UMR 7635, CS 10207 rue Claude Daunesse 06904 Sophia Antipolis Cedex (France)

    2016-05-18

    Despite of a lot of attempts during recent years, complex mechanical behaviour of polymers remains incompletely modelled, making industrial design of structures under complex, cyclic and hard loadings not totally reliable. The non linear and dissipative viscoelastic, viscoplastic behaviour of those materials impose to take into account non linear and combined effects of mechanical and thermal phenomena. In this view, a visco-hyperelastic, viscoplastic model, based on network description of the material has recently been developed and designed in a complete thermodynamic frame in order to take into account those main thermo-mechanical couplings. Also, a way to account for coupled effects of strain-rate and temperature was suggested. First experimental validations conducted in the 1D limit on amorphous rubbery like PMMA in isothermal conditions led to pretty goods results. In this paper a more complete formalism is presented and validated in the case of a semi crystalline polymer, a PA66 and a PET (either amorphous or semi crystalline) are used. Protocol for identification of constitutive parameters is described. It is concluded that this new approach should be the route to accurately model thermo-mechanical behaviour of polymers using a reduced number of parameters of some physical meaning.

  16. Time Synchronization and Distribution Mechanisms for Space Networks

    Science.gov (United States)

    Woo, Simon S.; Gao, Jay L.; Clare, Loren P.; Mills, David L.

    2011-01-01

    This work discusses research on the problems of synchronizing and distributing time information between spacecraft based on the Network Time Protocol (NTP), where NTP is a standard time synchronization protocol widely used in the terrestrial network. The Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol was designed and developed for synchronizing spacecraft that are in proximity where proximity is less than 100,000 km distant. A particular application is synchronization between a Mars orbiter and rover. Lunar scenarios as well as outer-planet deep space mother-ship-probe missions may also apply. Spacecraft with more accurate time information functions as a time-server, and the other spacecraft functions as a time-client. PITS can be easily integrated and adaptable to the CCSDS Proximity-1 Space Link Protocol with minor modifications. In particular, PITS can take advantage of the timestamping strategy that underlying link layer functionality provides for accurate time offset calculation. The PITS algorithm achieves time synchronization with eight consecutive space network time packet exchanges between two spacecraft. PITS can detect and avoid possible errors from receiving duplicate and out-of-order packets by comparing with the current state variables and timestamps. Further, PITS is able to detect error events and autonomously recover from unexpected events that can possibly occur during the time synchronization and distribution process. This capability achieves an additional level of protocol protection on top of CRC or Error Correction Codes. PITS is a lightweight and efficient protocol, eliminating the needs for explicit frame sequence number and long buffer storage. The PITS protocol is capable of providing time synchronization and distribution services for a more general domain where multiple entities need to achieve time synchronization using a single point-to-point link.

  17. To share and be shared

    DEFF Research Database (Denmark)

    Winther, Ida Wentzel

    2018-01-01

    to another. To a certain degree, they share their everyday lives, things, places, memories, and past/future, but as the ones who move back and forth, they belong a little less in each place. This article is about children who are shared between their parent, households and siblings. They are shared...

  18. Fast rise times and the physical mechanism of deep earthquakes

    Science.gov (United States)

    Houston, H.; Williams, Q.

    1991-01-01

    A systematic global survey of the rise times and stress drops of deep and intermediate earthquakes is reported. When the rise times are scaled to the seismic moment release of the events, their average is nearly twice as fast for events deeper than about 450 km as for shallower events.

  19. Changes in accountability mechanism in times of crisis

    DEFF Research Database (Denmark)

    Hansen, Hanne Foss; Kristiansen, Mads Bøge

    been adjusted downwards. As a result the pressure on the public finances has increased and public sector reforms are launched. This paper analyses how public sector accountability mechanisms are changed as part of crisis responses. The analysis shows that accountability dynamics are changing in favour...... of strengthening political, administrative and professional accountability mechanisms focused on the aspect of financial conduct. This is done by introducing a budgetary law increasing the surveillance of financial conduct by establishing new hierarchical and diagonal accountability relations. The role...... as a move towards classical economic public sector accountability thinking stressing the importance of fiscal discipline. In addition several important accountability institutions seems to further develop their accountability policies stressing another economic value namely effectiveness. Finally...

  20. Time and Classical and Quantum Mechanics Indeterminacy vs. Discontinuity

    CERN Document Server

    Lynds, P

    2001-01-01

    It is postulated there is not a precise static instant in time underlying a dynamical physical process at which the relative position of a body in relative motion or a specific physical magnitude would theoretically be precisely determined. It is concluded it is exactly because of this that time (relative interval as indicated by a clock) and the continuity of a physical process is possible, with there being a necessary trade off of all precisely determined physical values at a time, for their continuity through time. This explanation is also shown to be the correct solution to the motion and infinity paradoxes, excluding the Stadium, originally conceived by the ancient Greek mathematician Zeno of Elea. Quantum Cosmology, Imaginary Time and Chronons are also then discussed, with the latter two appearing to be superseded on a theoretical basis.

  1. Predicting multiprocessing efficiency on the Cray multiprocessors in a (CTSS) time-sharing environment/application to a 3-D magnetohydrodynamics code

    International Nuclear Information System (INIS)

    Mirin, A.A.

    1988-01-01

    A formula is derived for predicting multiprocessing efficiency on Cray supercomputers equipped with the Cray Time-Sharing System (CTSS). The model is applicable to an intensive time-sharing environment. The actual efficiency estimate depends on three factors: the code size, task length, and job mix. The implementation of multitasking in a three-dimensional plasma magnetohydrodynamics (MHD) code, TEMCO, is discussed. TEMCO solves the primitive one-fluid compressible MHD equations and includes resistive and Hall effects in Ohm's law. Virtually all segments of the main time-integration loop are multitasked. The multiprocessing efficiency model is applied to TEMCO. Excellent agreement is obtained between the actual multiprocessing efficiency and the theoretical prediction

  2. Unitarity and the time evolution of quantum mechanical states

    International Nuclear Information System (INIS)

    Kabir, P.K.; Pilaftsis, A.

    1996-01-01

    The basic requirement that, in quantum theory, the time evolution of any state is determined by the action of a unitary operator, is shown to be the underlying cause for certain open-quote open-quote exact close-quote close-quote results that have recently been reported about the time dependence of transition rates in quantum theory. Departures from exponential decay, including the open-quote open-quote quantum Zeno effect,close-quote close-quote as well as a theorem by Khalfin about the ratio of reciprocal transition rates, are shown to follow directly from such considerations. At sufficiently short times, unitarity requires that reciprocity must hold, independent of whether T invariance is valid. If T invariance does not hold, unitarity restricts the form of possible time dependence of reciprocity ratios. copyright 1996 The American Physical Society

  3. Psychological and neural mechanisms of subjective time dilation

    Directory of Open Access Journals (Sweden)

    Virginie evan Wassenhove

    2011-04-01

    Full Text Available For a given physical duration, certain events can be experienced as subjectively longer in duration than others. Try this for yourself: take a quick glance at the second hand of a clock. Immediately, the tick will pause momentarily and appear to be longer than the subsequent ticks. Yet, they all last exactly one second. By and large, a deviant or an unexpected stimulus in a series of similar events (same duration, same features can elicit a relative overestimation of subjective time (or "time dilation" but, as is shown here, this is not always the case. We conducted an event-related functional magnetic neuroimaging (fMRI study on the time dilation effect. Participants were presented with a series of five visual discs, all static and of equal duration (standards except for the fourth one, a looming or a receding target. The duration of the target was systematically varied and participants judged whether it was shorter or longer than all other standards in the sequence. Subjective time dilation was observed for the looming stimulus but not for the receding one, which was estimated to be of equal duration to the standards. The neural activation for targets (looming and receding contrasted with the standards revealed an increased activation of the anterior insula and of the anterior cingulate cortex. Contrasting the looming with the receding targets (i.e. capturing the time dilation effect proper revealed a specific activation of cortical midline structures. The implication of midline structures in the time dilation illusion is here interpreted in the context of self-referential processes.

  4. Sharing City

    DEFF Research Database (Denmark)

    This magazine offers an insight into the growing commercial innovation, civic movements, and political narratives surrounding sharing economy services, solutions and organisational types. It presents a cross-section of the manifold sharing economy services and solutions that can be found in Denmark....... Moreover, 15 thought leading experts - professionals and academic - have been invited to give their perspective on sharing economy for cities. This magazine touches upon aspects of the sharing economy as mobility, communities, sustainability, business development, mobility, and urban-rural relation....

  5. Using Simulated Partial Dynamic Run-Time Reconfiguration to Share Embedded FPGA Compute and Power Resources across a Swarm of Unpiloted Airborne Vehicles

    Directory of Open Access Journals (Sweden)

    Kearney David

    2007-01-01

    Full Text Available We show how the limited electrical power and FPGA compute resources available in a swarm of small UAVs can be shared by moving FPGA tasks from one UAV to another. A software and hardware infrastructure that supports the mobility of embedded FPGA applications on a single FPGA chip and across a group of networked FPGA chips is an integral part of the work described here. It is shown how to allocate a single FPGA's resources at run time and to share a single device through the use of application checkpointing, a memory controller, and an on-chip run-time reconfigurable network. A prototype distributed operating system is described for managing mobile applications across the swarm based on the contents of a fuzzy rule base. It can move applications between UAVs in order to equalize power use or to enable the continuous replenishment of fully fueled planes into the swarm.

  6. Life-time management for mechanical components; Lebensdauermanagement mechanischer Komponenten

    Energy Technology Data Exchange (ETDEWEB)

    Roos, E. [Stuttgart Univ. (DE). Materialpruefungsanstalt (MPA)

    2006-07-01

    The safety and economic efficiency of industrial systems depend on the quality of components and systems. In the field of power generation, power plants should be safe and have high availability and minimum specific generation cost. Life management is essential for this. Depending on the safety relevance of systems, structures and components (SSC), this includes proofs of integrity, time-oriented or condition-oriented preventive maintenance, or just failure-oriented maintenance. (orig.)

  7. File sharing

    NARCIS (Netherlands)

    van Eijk, N.

    2011-01-01

    ‘File sharing’ has become generally accepted on the Internet. Users share files for downloading music, films, games, software etc. In this note, we have a closer look at the definition of file sharing, the legal and policy-based context as well as enforcement issues. The economic and cultural

  8. Replacing the Ethernet access mechanism with the real-time access mechanism of Twentenet

    NARCIS (Netherlands)

    Pras, Aiko

    1989-01-01

    The way in which a Local Area Network access mechanism (Medium Access Control protocol) designed for a specific type of physical service can be used on top of another type of physical service is discussed using a particular example. In the example, an Ethernet physical layer is used to provide

  9. Synchronization as a biological, psychological and social mechanism to create common time: A theoretical frame and a single case study.

    Science.gov (United States)

    Bao, Yan; Pöppel, Ernst; Wang, Lingyan; Lin, Xiaoxiong; Yang, Taoxi; Avram, Mihai; Blautzik, Janusch; Paolini, Marco; Silveira, Sarita; Vedder, Aline; Zaytseva, Yuliya; Zhou, Bin

    2015-12-01

    Synchronizing neural processes, mental activities, and social interactions is considered to be fundamental for the creation of temporal order on the personal and interpersonal level. Several different types of synchronization are distinguished, and for each of them examples are given: self-organized synchronizations on the neural level giving rise to pre-semantically defined time windows of some tens of milliseconds and of approximately 3 s; time windows that are created by synchronizing different neural representations, as for instance in aesthetic appreciations or moral judgments; and synchronization of biological rhythms with geophysical cycles, like the circadian clock with the 24-hr rhythm of day and night. For the latter type of synchronization, an experiment is described that shows the importance of social interactions for sharing or avoiding common time. In a group study with four subjects being completely isolated together for 3 weeks from the external world, social interactions resulted both in intra- and interindividual circadian synchronization and desynchronization. A unique phenomenon in circadian regulation is described, the "beat phenomenon," which has been made visible by the interaction of two circadian rhythms with different frequencies in one body. The separation of the two physiological rhythms was the consequence of social interactions, that is, by the desire of a subject to share and to escape common time during different phases of the long-term experiment. The theoretical arguments on synchronization are summarized with the general statement: "Nothing in cognitive science makes sense except in the light of time windows." The hypothesis is forwarded that time windows that express discrete timing mechanisms in behavioral control and on the level of conscious experiences are the necessary bases to create cognitive order, and it is suggested that time windows are implemented by neural oscillations in different frequency domains. © 2015 The

  10. Time evolution of morphology in mechanically alloyed Fe-Cu

    KAUST Repository

    Wille, Catharina Gabriele

    2011-05-01

    Being widely accessible as well as already utilised in many applications, Fe-Cu acts as an ideal binary model alloy to elaborate the enforced nonequilibrium enhanced solubility in such a solution system that shows a limited regime of miscibility and characterised by a large positive heat of mixing. In addition to the detailed analysis of ball milled Fe-Cu powders by means of Atom Probe Tomography (APT), site specific structural analysis has been performed in this study using Transmission Electron Microscopy (TEM).In this contribution results on powders with low Cu concentrations (2.5-10 at%) are presented. Combining a ductile element (Cu, fcc) and a brittle one (Fe, bcc), striking differences in morphology were expected and found on all length-scales, depending on the mixing ratio of the two elements. However, not only could the atomic mixing of Fe and Cu be evaluated, but also the distribution of impurities, mostly stemming from the fabrication procedure. The combination of APT and TEM enables a correlation between the structural evolution and the chemical mixing during the milling process. For the first time, a clear distinction can be drawn between the morphological evolution at the surface and in the interior of the powder particles. This became possible owing to the site specific sample preparation of TEM lamellae by Focussed Ion Beam (FIB). Surprisingly, the texture arising from the ball milling process can directly be related to the classical rolling texture of cold rolled Fe. In addition, full homogeneity can be achieved even on the nano-scale for this material as shown by APT, resulting in an extended miscibility region in comparison to the equilibrium phase diagram. Grain sizes were determined by means of XRD and TEM. The strain corrected XRD results are in very good agreement with the values derived by TEM, both confirming a truly nanocrystalline structure. © 2011 Elsevier B.V.

  11. Traditional Knowledge in the Time of Neo-Liberalism: Access and Benefit-Sharing Regimes in India and Bhutan

    Directory of Open Access Journals (Sweden)

    Indrani Barpujari

    2017-03-01

    Full Text Available In a neoliberal world, traditional knowledge (TK of biodiversity possessed by Indigenous and Local Communities (ILCs in the global South has become a valuable "commodity" or "bio-resource," necessitating the setting up of harmonized ground rules (international and national in the form of an access and benefitsharing regime to facilitate its exchange in the world market. Despite criticisms that a regime with a neo-liberal orientation is antithetical to the normative ethos of ILCs, it could also offer a chance for developing countries and ILCs to generate revenue for socioeconomic development—to which they are gradually becoming open, but only under fair and equitable terms. Based on this context, this article proposes to look into the legal and policy frameworks and institutional regimes governing access and benefit sharing of TK associated with biological resources in two countries of South Asia: India and Bhutan. The article seeks to examine how such regimes are reconciling the imperatives of a neo-liberal economy with providing a just and equitable framework for ILCs and TK holders, which is truly participatory and not top-down.

  12. Exploring the Sharing Economy

    DEFF Research Database (Denmark)

    Netter, Sarah

    Despite the growing interest on the part of proponents and opponents - ranging from business, civil society, media, to policy-makers alike - there is still limited knowledge about the working mechanisms of the sharing economy. The thesis is dedicated to explore this understudied phenomenon...... and to provide a more nuanced understanding of the micro- and macro-level tensions that characterize the sharing economy. This thesis consists of four research papers, each using different literature, methodology, and data sets. The first paper investigates how the sharing economy is diffused and is ‘talked......-level tensions experience by sharing platforms by looking at the case of mobile fashion reselling and swapping markets. The final paper combines the perspectives of different sharing economy stakeholders and outlines some of the micro and macro tensions arising in and influencing the organization of these multi...

  13. Tunneling time distribution by means of Nelson's quantum mechanics and wave-particle duality

    International Nuclear Information System (INIS)

    Hara, Koh'ichiro; Ohba, Ichiro

    2003-01-01

    We calculate a tunneling time distribution by means of Nelson's quantum mechanics and investigate its statistical properties. The relationship between the average and deviation of tunneling time suggests the existence of 'wave-particle duality' in the tunneling phenomena

  14. TRF1 and TRF2 use different mechanisms to find telomeric DNA but share a novel mechanism to search for protein partners at telomeres.

    Science.gov (United States)

    Lin, Jiangguo; Countryman, Preston; Buncher, Noah; Kaur, Parminder; E, Longjiang; Zhang, Yiyun; Gibson, Greg; You, Changjiang; Watkins, Simon C; Piehler, Jacob; Opresko, Patricia L; Kad, Neil M; Wang, Hong

    2014-02-01

    Human telomeres are maintained by the shelterin protein complex in which TRF1 and TRF2 bind directly to duplex telomeric DNA. How these proteins find telomeric sequences among a genome of billions of base pairs and how they find protein partners to form the shelterin complex remains uncertain. Using single-molecule fluorescence imaging of quantum dot-labeled TRF1 and TRF2, we study how these proteins locate TTAGGG repeats on DNA tightropes. By virtue of its basic domain TRF2 performs an extensive 1D search on nontelomeric DNA, whereas TRF1's 1D search is limited. Unlike the stable and static associations observed for other proteins at specific binding sites, TRF proteins possess reduced binding stability marked by transient binding (∼ 9-17 s) and slow 1D diffusion on specific telomeric regions. These slow diffusion constants yield activation energy barriers to sliding ∼ 2.8-3.6 κ(B)T greater than those for nontelomeric DNA. We propose that the TRF proteins use 1D sliding to find protein partners and assemble the shelterin complex, which in turn stabilizes the interaction with specific telomeric DNA. This 'tag-team proofreading' represents a more general mechanism to ensure a specific set of proteins interact with each other on long repetitive specific DNA sequences without requiring external energy sources.

  15. Utility-maximizing model of household time use for independent, shared, and allocated activities incorporating group decision mechanisms

    NARCIS (Netherlands)

    Zhang, J.; Timmermans, H.J.P.; Borgers, A.W.J.

    2002-01-01

    Existing activity-based models of transport demand typically assume an individual decision-making process. The focus on theories of individual decision making may be partially due to the lack of behaviorally oriented modeling methodologies for group decision making. Therefore, an attempt has been

  16. The Mechanisms of Space-Time Association: Comparing Motor and Perceptual Contributions in Time Reproduction

    Science.gov (United States)

    Fabbri, Marco; Cellini, Nicola; Martoni, Monica; Tonetti, Lorenzo; Natale, Vincenzo

    2013-01-01

    The spatial-temporal association indicates that time is represented spatially along a left-to-right line. It is unclear whether the spatial-temporal association is mainly related to a perceptual or a motor component. In addition, the spatial-temporal association is not consistently found using a time reproduction task. Our rationale for this…

  17. Prospects of a mathematical theory of human behavior in complex man-machine systems tasks. [time sharing computer analogy of automobile driving

    Science.gov (United States)

    Johannsen, G.; Rouse, W. B.

    1978-01-01

    A hierarchy of human activities is derived by analyzing automobile driving in general terms. A structural description leads to a block diagram and a time-sharing computer analogy. The range of applicability of existing mathematical models is considered with respect to the hierarchy of human activities in actual complex tasks. Other mathematical tools so far not often applied to man machine systems are also discussed. The mathematical descriptions at least briefly considered here include utility, estimation, control, queueing, and fuzzy set theory as well as artificial intelligence techniques. Some thoughts are given as to how these methods might be integrated and how further work might be pursued.

  18. Elaboration of the international transfer mechanism of reduction in greenhouse gas emissions on the basis of the Russian federal law About agreements of products sharing'

    International Nuclear Information System (INIS)

    Toivonen, N.R.; Koulikovskaya, L.

    2001-01-01

    Suggestions for a comprehensive legal framework for the implementation in Russia of the flexibility mechanisms established under the Kyoto Protocol (i.e. joint implementation; clean development mechanism; international emissions trading) are proposed. It is suggested that the legal framework be established using the principles embodied in the existing Russian federal law, 'About agreements of product sharing' adopted in 1995. As a basic requirement, it is suggested that the new federal law must include the fundamental elements required to create possibilities for the Russian Federation to participate in the process of certified emission reductions (CER) transfer, emissions reduction unit (ERU) negotiation, and adjusted amount units (AAU) trading within the framework of the Kyoto Protocol implementation. The new law must also embody the basic procedures required to enter into agreements at the international, inter-regional and inter-sectoral levels. Failure to develop the legislative support and the legal framework to facilitate valid Russian participation in the implementation of the Kyoto Protocol will prevent many valuable initiatives and projects from being realized

  19. Time expenditure in computer aided time studies implemented for highly mechanized forest equipment

    Directory of Open Access Journals (Sweden)

    Elena Camelia Mușat

    2016-06-01

    Full Text Available Time studies represent important tools that are used in forest operations research to produce empirical models or to comparatively assess the performance of two or more operational alternatives with the general aim to predict the performance of operational behavior, choose the most adequate equipment or eliminate the useless time. There is a long tradition in collecting the needed data in a traditional fashion, but this approach has its limitations, and it is likely that in the future the use of professional software would be extended is such preoccupations as this kind of tools have been already implemented. However, little to no information is available in what concerns the performance of data analyzing tasks when using purpose-built professional time studying software in such research preoccupations, while the resources needed to conduct time studies, including here the time may be quite intensive. Our study aimed to model the relations between the variation of time needed to analyze the video-recorded time study data and the variation of some measured independent variables for a complex organization of a work cycle. The results of our study indicate that the number of work elements which were separated within a work cycle as well as the delay-free cycle time and the software functionalities that were used during data analysis, significantly affected the time expenditure needed to analyze the data (α=0.01, p<0.01. Under the conditions of this study, where the average duration of a work cycle was of about 48 seconds and the number of separated work elements was of about 14, the speed that was usedto replay the video files significantly affected the mean time expenditure which averaged about 273 seconds for half of the real speed and about 192 seconds for an analyzing speed that equaled the real speed. We argue that different study designs as well as the parameters used within the software are likely to produce

  20. Ditching the Disc: The Effects of Cloud-Based Image Sharing on Department Efficiency and Report Turnaround Times in Mammography.

    Science.gov (United States)

    Morgan, Matthew B; Young, Elizabeth; Harada, Scott; Winkler, Nicole; Riegert, Joanna; Jones, Tony; Hu, Nan; Stein, Matthew

    2017-12-01

    In screening mammography, accessing prior examination images is crucial for accurate diagnosis and avoiding false-positives. When women visit multiple institutions for their screens, these "outside" examinations must be retrieved for comparison. Traditionally, prior images are obtained by faxing requests to other institutions and waiting for standard mail (film or CD-ROM), which can greatly delay report turnaround times. Recently, advancements in cloud-based image transfer technology have opened up more efficient options for examination transfer between institutions. The objective of this study was to evaluate the effect of cloud-based image transfer on mammography department workflow, time required to obtain prior images, and report turnaround times. Sixty screening examinations requiring prior images were placed into two groups (30 each). The control group used the standard institutional protocol for requesting prior images: faxing requests and waiting for mailed examinations. The experimental group used a cloud-based transfer for both requesting and receiving examinations. The mean number of days between examination request and examination receipt was measured for both groups and compared. The mean number of days from examination request to receipt was 6.08 days (SD 3.50) in the control group compared with 3.16 days (SD 3.95) in the experimental group. Using a cloud-based image transfer to obtain prior mammograms resulted in an average reduction of 2.92 days (P = .0361; 95% confidence interval 0.20-5.65) between examination request and receipt. This improvement in system efficiency is relevant for interpreting radiologists working to improve reporting times and for patients anxious to receive their mammography results. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  1. Increasing Power by Sharing Information from Genetic Background and Treatment in Clustering of Gene Expression Time Series

    OpenAIRE

    Sura Zaki Alrashid; Muhammad Arifur Rahman; Nabeel H Al-Aaraji; Neil D Lawrence; Paul R Heath

    2018-01-01

    Clustering of gene expression time series gives insight into which genes may be co-regulated, allowing us to discern the activity of pathways in a given microarray experiment. Of particular interest is how a given group of genes varies with different conditions or genetic background. This paper develops
a new clustering method that allows each cluster to be parameterised according to whether the behaviour of the genes across conditions is correlated or anti-correlated. By specifying correlati...

  2. Story time turbocharger? Child engagement during shared reading and cerebellar activation and connectivity in preschool-age children listening to stories.

    Directory of Open Access Journals (Sweden)

    John S Hutton

    Full Text Available Expanding behavioral and neurobiological evidence affirms benefits of shared (especially parent-child reading on cognitive development during early childhood. However, the majority of this evidence involves factors under caregiver control, the influence of those intrinsic to the child, such as interest or engagement in reading, largely indirect or unclear. The cerebellum is increasingly recognized as playing a "smoothing" role in higher-level cognitive processing and learning, via feedback loops with language, limbic and association cortices. We utilized functional MRI to explore the relationship between child engagement during a mother-child reading observation and neural activation and connectivity during a story listening task, in a sample of 4-year old girls. Children exhibiting greater interest and engagement in the narrative showed increased activation in right-sided cerebellar association areas during the task, and greater functional connectivity between this activation cluster and language and executive function areas. Our findings suggest a potential cerebellar "boost" mechanism responsive to child engagement level that may contribute to emergent literacy development during early childhood, and synergy between caregiver and child factors during story sharing.

  3. Inter-Firm Information Sharing in Enterprise Resource Planning Systems: a call for timely but limited access to customer information

    Directory of Open Access Journals (Sweden)

    Michael Busing

    2001-11-01

    Full Text Available Current trends in Enterprise Resource Planning (ERP suggest that supply chain management and tight control over scheduling jobs within the supply chain are key tactical planning issues. Modern ERP software packages, in conjunction with the World Wide Web, allow for automated exchange of information within a company and also between two or more companies (i.e., conveyance of customer information to suppliers of parts and components for the purposes of effective planning and control. While ease of information exchange between a customer and supplier is increasingly critical to the success of modern-day planning and control efforts, the issue of information security is also a very real concern. Suppliers can benefit from gaining access to a customer's dispatch list and material requirements plan (MRP in order to determine real-time priority of jobs in queue at various work centers within their own organization. Other customer information, however, should remain secure and unavailable to supplier firms for competitive reasons such as threat of forward integration. This paper presents a previously tested priority-sequencing rule that explicitly considers downstream shop conditions in determining which job to run next The rule proves to perform well on mean flow time and lateness as well as on variability of these measures. The rule is extended here to incorporate the case where a downstream work center is outside official corporate boundaries. With the call for free exchange of information comes the threat of other, perhaps proprietary, information being accessed by vendors or others outside the official corporate boundaries. The paper will propose information that should be freely exchanged between customers and suppliers and information that should remain secure. Finally, practical measures to manage access to web-enabled ERP information will be proposed.

  4. Effectiveness of anonymised information sharing and use in health service, police, and local government partnership for preventing violence related injury: experimental study and time series analysis

    Science.gov (United States)

    Florence, Curtis; Brennan, Iain; Simon, Thomas

    2011-01-01

    Objective To evaluate the effectiveness of anonymised information sharing to prevent injury related to violence. Design Experimental study and time series analysis of a prototype community partnership between the health service, police, and local government partners designed to prevent violence. Setting Cardiff, Wales, and 14 comparison cities designated “most similar” by the Home Office in England and Wales. Intervention After a 33 month development period, anonymised data relevant to violence prevention (precise violence location, time, days, and weapons) from patients attending emergency departments in Cardiff and reporting injury from violence were shared over 51 months with police and local authority partners and used to target resources for violence prevention. Main outcome measures Health service records of hospital admissions related to violence and police records of woundings and less serious assaults in Cardiff and other cities after adjustment for potential confounders. Results Information sharing and use were associated with a substantial and significant reduction in hospital admissions related to violence. In the intervention city (Cardiff) rates fell from seven to five a month per 100 000 population compared with an increase from five to eight in comparison cities (adjusted incidence rate ratio 0.58, 95% confidence interval 0.49 to 0.69). Average rate of woundings recorded by the police changed from 54 to 82 a month per 100 000 population in Cardiff compared with an increase from 54 to 114 in comparison cities (adjusted incidence rate ratio 0.68, 0.61 to 0.75). There was a significant increase in less serious assaults recorded by the police, from 15 to 20 a month per 100 000 population in Cardiff compared with a decrease from 42 to 33 in comparison cities (adjusted incidence rate ratio 1.38, 1.13 to 1.70). Conclusion An information sharing partnership between health services, police, and local government in Cardiff, Wales, altered policing

  5. New Technologies: Real-time Telepathology Systems-Novel Cost-effective Tools for Real-time Consultation and Data Sharing.

    Science.gov (United States)

    Siegel, Gabriel; Regelman, Dan; Maronpot, Robert; Rosenstock, Moti; Nyska, Abraham

    2017-12-01

    Real-time telepathology for use in investigative and regulated preclinical toxicology studies is now feasible. Newly developed microscope-integrated telepathology systems enable geographically remote stakeholders to view the live histopathology slide as seen by the study pathologist within the microscope. Simultaneous online viewing and dialog between study pathologist and remote colleagues is an efficient and cost-effective means for consultation, pathology working groups, and peer review, facilitating good science and economic benefits by enabling more timely and informed clinical decisions.

  6. Passenger Sharing of the High-Speed Railway from Sensitivity Analysis Caused by Price and Run-time Based on the Multi-Agent System

    Directory of Open Access Journals (Sweden)

    Ma Ning

    2013-09-01

    Full Text Available Purpose: Nowadays, governments around the world are active in constructing the high-speed railway. Therefore, it is significant to make research on this increasingly prevalent transport.Design/methodology/approach: In this paper, we simulate the process of the passenger’s travel mode choice by adjusting the ticket fare and the run-time based on the multi-agent system (MAS.Findings: From the research we get the conclusion that increasing the run-time appropriately and reducing the ticket fare in some extent are effective ways to enhance the passenger sharing of the high-speed railway.Originality/value: We hope it can provide policy recommendations for the railway sectors in developing the long-term plan on high-speed railway in the future.

  7. The benefits and challenges of sharing glidein factory operations across nine time zones between OSG and CMS

    Science.gov (United States)

    Sfiligoi, I.; Dost, J. M.; Zvada, M.; Butenas, I.; Holzman, B.; Wuerthwein, F.; Kreuzer, P.; Teige, S. W.; Quick, R.; Hernández, J. M.; Flix, J.

    2012-12-01

    OSG has been operating for a few years at UCSD a glideinWMS factory for several scientific communities, including CMS analysis, HCC and GLOW. This setup worked fine, but it had become a single point of failure. OSG thus recently added another instance at Indiana University, serving the same user communities. Similarly, CMS has been operating a glidein factory dedicated to reprocessing activities at Fermilab, with similar results. Recently, CMS decided to host another glidein factory at CERN, to increase the availability of the system, both for analysis, MC and reprocessing jobs. Given the large overlap between this new factory and the three factories in the US, and given that CMS represents a significant fraction of glideins going through the OSG factories, CMS and OSG formed a common operations team that operates all of the above factories. The reasoning behind this arrangement is that most operational issues stem from Grid-related problems, and are very similar for all the factory instances. Solving a problem in one instance thus very often solves the problem for all of them. This paper presents the operational experience of how we address both the social and technical issues of running multiple instances of a glideinWMS factory with operations staff spanning multiple time zones on two continents.

  8. Real-time electricity pricing mechanism in China based on system dynamics

    International Nuclear Information System (INIS)

    He, Yongxiu; Zhang, Jixiang

    2015-01-01

    Highlights: • The system dynamics is used to research the real-time electricity pricing mechanism. • Four kinds of the real-time electricity pricing models are carried out and simulated. • It analysed the electricity price, the user satisfaction and the social benefits under the different models. • Market pricing is the trend of the real-time electricity pricing mechanism. • Initial development path of the real-time price mechanism for China is designed between 2015 and 2030. - Abstract: As an important means of demand-side response, the reasonable formulation of the electricity price mechanism will have an important impact on the balance between the supply and demand of electric power. With the introduction of Chinese intelligence apparatus and the rapid development of smart grids, real-time electricity pricing, as the frontier electricity pricing mechanism in the smart grid, will have great significance on the promotion of energy conservation and the improvement of the total social surplus. From the perspective of system dynamics, this paper studies different real-time electricity pricing mechanisms based on load structure, cost structure and bidding and analyses the situation of user satisfaction and the total social surplus under different pricing mechanisms. Finally, through the comparative analysis of examples under different real-time pricing scenarios, this paper aims to explore and design the future dynamic real-time electricity pricing mechanism in China, predicts the dynamic real-time pricing level and provides a reference for real-time electricity price promotion in the future

  9. Global resource sharing

    CERN Document Server

    Frederiksen, Linda; Nance, Heidi

    2011-01-01

    Written from a global perspective, this book reviews sharing of library resources on a global scale. With expanded discovery tools and massive digitization projects, the rich and extensive holdings of the world's libraries are more visible now than at any time in the past. Advanced communication and transmission technologies, along with improved international standards, present a means for the sharing of library resources around the globe. Despite these significant improvements, a number of challenges remain. Global Resource Sharing provides librarians and library managers with a comprehensive

  10. A Study of the Effect of Reward system’s Mechanisms on New Product development considering the mediating role of Knowledge-Sharing (Case study: Home Appliances Province Manufacturing Companies in Esfahan)

    OpenAIRE

    Hassan Ghorbani; Tania Ladoni

    2013-01-01

    The present paper, titled ‘A Study of the Effect of reward systemʼs mechanisms on new product development the mediating role of knowledge-sharing’ examines the important role of rewarding mechanisms in facilitating the knowledge-sharing among individuals and the effects of a joint reward system on knowledge-sharing among the members and the new product development performance in home appliances factories in Isfahan Province. This research, in terms of its purpose, is an applied one; and in te...

  11. Current sharing temperature of NbTi SULTAN samples compared to prediction using a single pinning mechanism parametrization for NbTi strand

    International Nuclear Information System (INIS)

    Pong, Ian; Vostner, Alexander; Devred, Arnaud; Bessette, Denis; Mitchell, Neil; Bordini, Bernardo; Bottura, Luca; Jewell, Matthew; Long Feng; Wu Yu

    2012-01-01

    NbTi strands to be used in four of the six ITER poloidal field (PF) coils, all the correction coils (CC) and all the superconducting feeder busbars are being produced in China. Short full-size qualification conductor (cabled and jacketed) samples have been developed at ASIPP and tested at CRPP. Single pinning mechanism parametrization for this Chinese strand (type S2) has been obtained using the Bottura scaling law. The determination of the scaling parameters using a Kramer-type regression method will be described. A comparison between the critical temperature at the operating current and field of a single strand as determined by the parametrization and the current sharing temperature (T CS ) of a few conductor samples tested at the SULTAN facility will be made. The validity and limitation of the estimation will be discussed. The estimated T CS dependence on various (superconducting critical as well as geometric and volumetric) parameters will be assessed using the modelled critical surface. Errors propagated from critical current (I c ) measurements of the strands and parameter fitting, and other uncertainties, will be quantified. (paper)

  12. Time-dependent mechanical behavior of human amnion: Macroscopic and microscopic characterization

    OpenAIRE

    2014-01-01

    © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. Characterizing the mechanical response of the human amnion is essential to understand and to eventually prevent premature rupture of fetal membranes. In this study a large set of macroscopic and microscopic mechanical tests have been carried out on fresh unfixed amnion to gain insight into the time dependent material response and the underlying mechanisms. Creep and relaxation responses of amnion were characterized in...

  13. Discretization of space and time in wave mechanics: the validity limit

    OpenAIRE

    Roatta , Luca

    2017-01-01

    Assuming that space and time can only have discrete values, it is shown that wave mechanics must necessarily have a specific applicability limit: in a discrete context, unlike in a continuous one, frequencies can not have arbitrarily high values.

  14. Effect of a Disintegration Mechanism on Wetting, Water Absorption, and Disintegration Time of Orodispersible Tablets

    OpenAIRE

    Pabari, RM; Ramtoola, Z

    2012-01-01

    The aim of this study was to evaluate the influence of disintegration mechanism of various types of disintegrants on the absorption ratio (AR), wetting time (WT), and disintegration time (DT) of orodispersible tablets (ODTs). ODTs were prepared by direct compression using mannitol as filler and disintegrants selected from a range of swellable, osmotic, and porous disintegrants. Tablets formed were characterized for their water AR, WT, and DT. The porosity and mechanical strength of the tablet...

  15. The criterion for time symmetry of probabilistic theories and the reversibility of quantum mechanics

    International Nuclear Information System (INIS)

    Holster, A T

    2003-01-01

    Physicists routinely claim that the fundamental laws of physics are 'time symmetric' or 'time reversal invariant' or 'reversible'. In particular, it is claimed that the theory of quantum mechanics is time symmetric. But it is shown in this paper that the orthodox analysis suffers from a fatal conceptual error, because the logical criterion for judging the time symmetry of probabilistic theories has been incorrectly formulated. The correct criterion requires symmetry between future-directed laws and past-directed laws. This criterion is formulated and proved in detail. The orthodox claim that quantum mechanics is reversible is re-evaluated. The property demonstrated in the orthodox analysis is shown to be quite distinct from time reversal invariance. The view of Satosi Watanabe that quantum mechanics is time asymmetric is verified, as well as his view that this feature does not merely show a de facto or 'contingent' asymmetry, as commonly supposed, but implies a genuine failure of time reversal invariance of the laws of quantum mechanics. The laws of quantum mechanics would be incompatible with a time-reversed version of our universe

  16. Modelling time-dependent mechanical behaviour of softwood using deformation kinetics

    DEFF Research Database (Denmark)

    Engelund, Emil Tang; Svensson, Staffan

    2010-01-01

    The time-dependent mechanical behaviour (TDMB) of softwood is relevant, e.g., when wood is used as building material where the mechanical properties must be predicted for decades ahead. The established mathematical models should be able to predict the time-dependent behaviour. However, these models...... are not always based on the actual physical processes causing time-dependent behaviour and the physical interpretation of their input parameters is difficult. The present study describes the TDMB of a softwood tissue and its individual tracheids. A model is constructed with a local coordinate system that follows...... macroscopic viscoelasticity, i.e., the time-dependent processes are to a significant degree reversible....

  17. A relational solution to the problem of time in quantum mechanics and quantum gravity: a fundamental mechanism for quantum decoherence

    International Nuclear Information System (INIS)

    Gambini, Rodolfo; Porto, Rafael A; Pullin, Jorge

    2004-01-01

    The use of a relational time in quantum mechanics is a framework in which one promotes to quantum operators all variables in a system, and later chooses one of the variables to operate like a 'clock'. Conditional probabilities are computed for variables of the system to take certain values when the 'clock' specifies a certain time. This framework is attractive in contexts where the assumption of usual quantum mechanics of the existence of an external, perfectly classical clock, appears unnatural, as in quantum cosmology. Until recently, there were problems with such constructions in ordinary quantum mechanics with additional difficulties in the context of constrained theories like general relativity. A scheme we recently introduced to consistently discretize general relativity removed such obstacles. Since the clock is now an object subject to quantum fluctuations, the resulting evolution in time is not exactly unitary and pure states decohere into mixed states. Here we work out in detail the type of decoherence generated, and we find it to be of Lindblad type. This is attractive since it implies that one can have loss of coherence without violating the conservation of energy. We apply the framework to a simple cosmological model to illustrate how a quantitative estimate of the effect could be computed. For most quantum systems it appears to be too small to be observed, although certain macroscopic quantum systems could in the future provide a testing ground for experimental observation

  18. Regulating the sharing economy

    Directory of Open Access Journals (Sweden)

    Kristofer Erickson

    2016-06-01

    Full Text Available In this introductory essay, we explore definitions of the ‘sharing economy’, a concept indicating both social (relational, communitarian and economic (allocative, profit-seeking aspects which appear to be in tension. We suggest combining the social and economic logics of the sharing economy to focus on the central features of network enabled, aggregated membership in a pool of offers and demands (for goods, services, creative expressions. This definition of the sharing economy distinguishes it from other related peer-to-peer and collaborative forms of production. Understanding the social and economic motivations for and implications of participating in the sharing economy is important to its regulation. Each of the papers in this special issue contributes to knowledge by linking the social and economic aspects of sharing economy practices to regulatory norms and mechanisms. We conclude this essay by suggesting future research to further clarify and render intelligible the sharing economy, not as a contradiction in terms but as an empirically observable realm of socio-economic activity.

  19. Domain-general involvement of the posterior frontolateral cortex in time-based resource-sharing in working memory: An fMRI study.

    Science.gov (United States)

    Vergauwe, Evie; Hartstra, Egbert; Barrouillet, Pierre; Brass, Marcel

    2015-07-15

    Working memory is often defined in cognitive psychology as a system devoted to the simultaneous processing and maintenance of information. In line with the time-based resource-sharing model of working memory (TBRS; Barrouillet and Camos, 2015; Barrouillet et al., 2004), there is accumulating evidence that, when memory items have to be maintained while performing a concurrent activity, memory performance depends on the cognitive load of this activity, independently of the domain involved. The present study used fMRI to identify regions in the brain that are sensitive to variations in cognitive load in a domain-general way. More precisely, we aimed at identifying brain areas that activate during maintenance of memory items as a direct function of the cognitive load induced by both verbal and spatial concurrent tasks. Results show that the right IFJ and bilateral SPL/IPS are the only areas showing an increased involvement as cognitive load increases and do so in a domain general manner. When correlating the fMRI signal with the approximated cognitive load as defined by the TBRS model, it was shown that the main focus of the cognitive load-related activation is located in the right IFJ. The present findings indicate that the IFJ makes domain-general contributions to time-based resource-sharing in working memory and allowed us to generate the novel hypothesis by which the IFJ might be the neural basis for the process of rapid switching. We argue that the IFJ might be a crucial part of a central attentional bottleneck in the brain because of its inability to upload more than one task rule at once. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Relationship between transit time and mechanical properties of a cell through a stenosed microchannel.

    Science.gov (United States)

    Ye, Ting; Shi, Huixin; Phan-Thien, Nhan; Lim, Chwee Teck; Li, Yu

    2018-01-24

    The changes in the mechanical properties of a cell are not only the cause of some diseases, but can also be a biomarker for some disease states. In recent times, microfluidic devices with built-in constrictions have been widely used to measure these changes. The transit time in such devices, defined as the time that a cell takes to pass through a constriction, has been found to be a crucial factor associated with the cell mechanical properties. Here, we use smoothed dissipative particle dynamics (SDPD), a particle-based numerical method, to explore the relationship between the transit time and mechanical properties of a cell. Three expressions of the transit time are developed from our simulation data, with respect to the stenosed size of constrictions, the shear modulus and bending modulus of cells, respectively. We show that a convergent constriction (the inlet is wider than the outlet), and a sharp-corner constriction (the constriction outlet is narrow) are better in identifying the differences in the transit time of cells. Moreover, the transit time increases and gradually approaches a constant as the shear modulus of cells increases, but increases first and then decreases as the bending modulus increases. These results suggest that the mechanical properties of cells can indeed be measured by analyzing their transit time, based on the recommended microfluidic device.

  1. Sharing knowledge

    Energy Technology Data Exchange (ETDEWEB)

    2009-07-01

    The workshop on Climate Change Impacts and Adaptation Strategies for Arctic Indigenous Communities is one stage in developing positions and providing input from the perspectives of Arctic Peoples in preparation for the Indigenous Peoples' Global Summit on Climate Change that will take place in April, 2009, in Anchorage, Alaska. The Summit, organized by the Inuit Circumpolar Council with oversight of an International Steering Committee, will bring together hundreds of indigenous Peoples around the world. This Workshop intended to bring together Arctic Indigenous Peoples to deliver and to share information, academic research, case studies based on traditional knowledge and researchers knowledgeable in traditional knowledge and/or policy issues drawn from traditional knowledge. The following themes were discussed: 1) Traditional knowledge research and education; 2) Laws and lawmaking; 3) Food and health; 4) Organisation; 5) Communications and advocacy. (ln)

  2. Detecting method for crude oil price fluctuation mechanism under different periodic time series

    International Nuclear Information System (INIS)

    Gao, Xiangyun; Fang, Wei; An, Feng; Wang, Yue

    2017-01-01

    Highlights: • We proposed the concept of autoregressive modes to indicate the fluctuation patterns. • We constructed transmission networks for studying the fluctuation mechanism. • There are different fluctuation mechanism under different periodic time series. • Only a few types of autoregressive modes control the fluctuations in crude oil price. • There are cluster effects during the fluctuation mechanism of autoregressive modes. - Abstract: Current existing literatures can characterize the long-term fluctuation of crude oil price time series, however, it is difficult to detect the fluctuation mechanism specifically under short term. Because each fluctuation pattern for one short period contained in a long-term crude oil price time series have dynamic characteristics of diversity; in other words, there exhibit various fluctuation patterns in different short periods and transmit to each other, which reflects the reputedly complicate and chaotic oil market. Thus, we proposed an incorporated method to detect the fluctuation mechanism, which is the evolution of the different fluctuation patterns over time from the complex network perspective. We divided crude oil price time series into segments using sliding time windows, and defined autoregressive modes based on regression models to indicate the fluctuation patterns of each segment. Hence, the transmissions between different types of autoregressive modes over time form a transmission network that contains rich dynamic information. We then capture transmission characteristics of autoregressive modes under different periodic time series through the structure features of the transmission networks. The results indicate that there are various autoregressive modes with significantly different statistical characteristics under different periodic time series. However, only a few types of autoregressive modes and transmission patterns play a major role in the fluctuation mechanism of the crude oil price, and these

  3. Application of Mathematica Software for Estimate the Fatigue Life Time Duration of Mechanical System

    Directory of Open Access Journals (Sweden)

    Petru Florin Minda

    2010-10-01

    Full Text Available The paper present how we can use Mathematica to solve the equations types usually used to determinate the maximum stress cycles that can be support by a mechanical system until he will be out of use. To illustrate the type of equations used in specialized literature to estimate fatigue life time duration was chosen a specific case of mechanical structure applied to fatigue. It is about lever button of runner blade mechanism of Kaplan turbine, that in function support a very intensive alternative strain.

  4. Influence of temperature on patch residence time in parasitoids: physiological and behavioural mechanisms

    Science.gov (United States)

    Moiroux, Joffrey; Abram, Paul K.; Louâpre, Philippe; Barrette, Maryse; Brodeur, Jacques; Boivin, Guy

    2016-04-01

    Patch time allocation has received much attention in the context of optimal foraging theory, including the effect of environmental variables. We investigated the direct role of temperature on patch time allocation by parasitoids through physiological and behavioural mechanisms and its indirect role via changes in sex allocation and behavioural defences of the hosts. We compared the influence of foraging temperature on patch residence time between an egg parasitoid, Trichogramma euproctidis, and an aphid parasitoid, Aphidius ervi. The latter attacks hosts that are able to actively defend themselves, and may thus indirectly influence patch time allocation of the parasitoid. Patch residence time decreased with an increase in temperature in both species. The increased activity levels with warming, as evidenced by the increase in walking speed, partially explained these variations, but other mechanisms were involved. In T. euproctidis, the ability to externally discriminate parasitised hosts decreased at low temperature, resulting in a longer patch residence time. Changes in sex allocation with temperature did not explain changes in patch time allocation in this species. For A. ervi, we observed that aphids frequently escaped at intermediate temperature and defended themselves aggressively at high temperature, but displayed few defence mechanisms at low temperature. These defensive behaviours resulted in a decreased patch residence time for the parasitoid and partly explained the fact that A. ervi remained for a shorter time at the intermediate and high temperatures than at the lowest temperature. Our results suggest that global warming may affect host-parasitoid interactions through complex mechanisms including both direct and indirect effects on parasitoid patch time allocation.

  5. Quantum mechanics in curved space-time and its consequences for the theory on the flat space-time

    International Nuclear Information System (INIS)

    Tagirov, E.A.

    1997-01-01

    Thus, the structure is extracted from the initial general-relativistic setting of the quantum theory of the scalar field φ that can be considered as quantum mechanics in V 1,3 in the Schroedinger picture, which includes relativistic corrections not only in the Hamiltonian of the Schroedinger equation but also in the operators of primary observables. In the terms pertaining to these corrections the operators differ from their counterparts resulting from quantization of a classical spinless particle. In general, they do not commute at all and thus the quantum phase space loses the feature that half its coordinates retain a manifold structure, which Biedenharn called 'a miracle of quantization'. This non-commutativity expands up to the exact (in the sense 'non-asymptotic in c -2 ') quantum mechanics of a free motion in the Minkowski space-time if curvilinear coordinates are taken as observables, which are necessary if non-inertial frames of references are considered

  6. On the definition of the time evolution operator for time-independent Hamiltonians in non-relativistic quantum mechanics

    Science.gov (United States)

    Amaku, Marcos; Coutinho, Francisco A. B.; Masafumi Toyama, F.

    2017-09-01

    The usual definition of the time evolution operator e-i H t /ℏ=∑n=0∞1/n ! (-i/ℏHt ) n , where H is the Hamiltonian of the system, as given in almost every book on quantum mechanics, causes problems in some situations. The operators that appear in quantum mechanics are either bounded or unbounded. Unbounded operators are not defined for all the vectors (wave functions) of the Hilbert space of the system; when applied to some states, they give a non-normalizable state. Therefore, if H is an unbounded operator, the definition in terms of the power series expansion does not make sense because it may diverge or result in a non-normalizable wave function. In this article, we explain why this is so and suggest, as an alternative, another definition used by mathematicians.

  7. The effects of activity-travel context and individual attitudes on car-sharing decisions under travel time uncertainty : a hybrid choice modeling approach

    NARCIS (Netherlands)

    Kim, J.; Rasouli, S.; Timmermans, H.J.P.

    2017-01-01

    People's daily decision to use car-sharing rather than other transport modes for conducting a specific activity has been investigated recently in assessing the market potential of car-sharing systems. Most studies have estimated transport mode choice models with an extended choice set using

  8. A time-based admission control mechanism for IEEE 802.11 ad Hoc networks

    OpenAIRE

    Costa, Luís Henrique M. K.; Cerveira, Carlos Rodrigo

    2006-01-01

    This paper presents a time-based admission control mechanism (TAC) for IEEE 802.11 ad hoc networks. The proposed mechanism was adapted to the QoS AODV routing protocol, which takes the quality of service requirements of the data flow into account in the route discovery process. TAC-AODV estimates the idle time of the physical medium based on the frames listened. The incoming traffic is admitted according to the offered load as well as the intra-flow interference, calculated based on the numbe...

  9. A mechanical nanomembrane detector for time-of-flight mass spectrometry.

    Science.gov (United States)

    Park, Jonghoo; Qin, Hua; Scalf, Mark; Hilger, Ryan T; Westphall, Michael S; Smith, Lloyd M; Blick, Robert H

    2011-09-14

    We describe here a new principle for ion detection in time-of-flight (TOF) mass spectrometry in which an impinging ion packet excites mechanical vibrations in a silicon nitride (Si(3)N(4)) nanomembrane. The nanomembrane oscillations are detected by means of time-varying field emission of electrons from the mechanically oscillating nanomembrane. Ion detection is demonstrated in the MALDI-TOF analysis of proteins varying in mass from 5729 (insulin) to 150,000 (Immunoglobulin G) daltons. The detector response agrees well with the predictions of a thermomechanical model in which the impinging ion packet causes a nonuniform temperature distribution in the nanomembrane, exciting both fundamental and higher order oscillations.

  10. Respiratory system dynamical mechanical properties: modeling in time and frequency domain.

    Science.gov (United States)

    Carvalho, Alysson Roncally; Zin, Walter Araujo

    2011-06-01

    The mechanical properties of the respiratory system are important determinants of its function and can be severely compromised in disease. The assessment of respiratory system mechanical properties is thus essential in the management of some disorders as well as in the evaluation of respiratory system adaptations in response to an acute or chronic process. Most often, lungs and chest wall are treated as a linear dynamic system that can be expressed with differential equations, allowing determination of the system's parameters, which will reflect the mechanical properties. However, different models that encompass nonlinear characteristics and also multicompartments have been used in several approaches and most specifically in mechanically ventilated patients with acute lung injury. Additionally, the input impedance over a range of frequencies can be assessed with a convenient excitation method allowing the identification of the mechanical characteristics of the central and peripheral airways as well as lung periphery impedance. With the evolution of computational power, the airway pressure and flow can be recorded and stored for hours, and hence continuous monitoring of the respiratory system mechanical properties is already available in some mechanical ventilators. This review aims to describe some of the most frequently used models for the assessment of the respiratory system mechanical properties in both time and frequency domain.

  11. Governing Individual Knowledge Sharing Behavior

    DEFF Research Database (Denmark)

    Minbaeva, Dana; Pedersen, Torben

    2010-01-01

    The emerging Knowledge Governance Approach asserts the need to build microfoundations grounded in individual action. Toward this goal, using the Theory of Planned Behavior, we aim to explain individual knowledge sharing behavior as being determined by the intention to share knowledge and its...... antecedents: attitude toward knowledge sharing, subjective norms, and perceived behavioral control. In addition, we consider managerial interventions (governance mechanisms) that managers can employ to influence the identified antecedents and thereby govern individual knowledge sharing behavior. We test...... a positive effect on subjective norms and perceived behavioral control, respectively....

  12. Regional differences in recipient waitlist time and pre- and post-transplant mortality after the 2006 United Network for Organ Sharing policy changes in the donor heart allocation algorithm.

    Science.gov (United States)

    Schulze, P Christian; Kitada, Shuichi; Clerkin, Kevin; Jin, Zhezhen; Mancini, Donna M

    2014-04-01

    This study examined the impact of the United Network for Organ Sharing (UNOS) policy changes for regional differences in waitlist time and mortality before and after heart transplantation. The 2006 UNOS thoracic organ allocation policy change was implemented to allow for greater regional sharing of organs for heart transplantation. We analyzed 36,789 patients who were listed for heart transplantation from January 1999 through April 2012. These patients were separated into 2 eras centered on the July 12, 2006 UNOS policy change. Pre- and post-transplantation characteristics were compared by UNOS regions. Waitlist mortality decreased nationally (up to 180 days: 13.3% vs. 7.9% after the UNOS policy change, p < 0.001) and within each region. Similarly, 2-year post-transplant mortality decreased nationally (2-year mortality: 17.3% vs. 14.6%; p < 0.001) as well as regionally. Waitlist time for UNOS status 1A and 1B candidates increased nationally 17.8 days on average (p < 0.001) with variability between the regions. The greatest increases were in Region 9 (59.2-day increase, p < 0.001) and Region 4 (41.2-day increase, p < 0.001). Although the use of mechanical circulatory support increased nearly 2.3-fold nationally in Era 2, significant differences were present on a regional basis. In Regions 6, 7, and 10, nearly 40% of those transplanted required left ventricular assist device bridging, whereas only 19.6%, 22.3%, and 15.5% required a left ventricular assist device in regions 3, 4, and 5, respectively. The 2006 UNOS policy change has resulted in significant regional heterogeneity with respect to waitlist time and reliance on mechanical circulatory support as a bridge to transplantation, although overall both waitlist mortality and post-transplant survival are improved. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  13. The effect warming time of mechanical properties and structural phase aluminum alloy nickel

    International Nuclear Information System (INIS)

    Husna Al Hasa, M.; Anwar Muchsin

    2011-01-01

    Ferrous aluminum alloys as fuel cladding will experience the process of heat treatment above the recrystallization temperature. Temperature and time of heat treatment will affect the nature of the metal. Heating time allows will affect change in mechanical properties, thermal and structure of the metal phase. This study aims to determine the effect of time of heat treatment on mechanical properties and phase metal alloys. Testing the mechanical properties of materials, especially violence done by the method of Vickers. Observation of microstructural changes made by metallographic-optical and phase structure were analyzed Based on the x-ray diffraction patterns Elemental analysis phase alloy compounds made by EDS-SEM. Test results show the nature of violence AlFeNiMg alloy by heating at 500°C with a warm-up time 1 hour, 2 hours and 3 hours respectively decreased range 94.4 HV, 87.6 HV and 85.1 HV. The nature of violence AlFeNi alloy showed a decrease in line with the longer heating time. Metallographic-optical observations show the microstructural changes with increasing heating time. Microstructure shows the longer the heating time trend equi axial shaped grain structure of growing and the results showed a trend analyst diffraction pattern formation and phase θ α phase (FeAl3) in the alloy. (author)

  14. Job Sharing in the Schools.

    Science.gov (United States)

    Moorman, Barbara; And Others

    Job sharing is defined as "two people sharing the responsibilities of one full-time position with salary and benefits prorated"; the concept focuses on positions usually offered only as full-time jobs, often in professional and managerial categories. This book is a guide for teachers and administrators on the implementation and use of…

  15. Sharing (and) familiarities

    DEFF Research Database (Denmark)

    Rasmussen, Jon Dag; Winther, Ida Wentzel; Davies, Hayley

    but not exclusive to lifestories/biographies, travels, times, spaces and material items, bodies and intimate knowledge of one another, surnames - in the subjective lives of family members? Sociology has traditionally been preoccupied with notions and logics of sharing in homely contexts (e.g. Simmel’s work...

  16. The Concept, Measurement, and Mechanism of Shared Leadership%共享型领导的概念、测量与作用机制

    Institute of Scientific and Technical Information of China (English)

    蒿坡; 龙立荣

    2017-01-01

    Due to the flat structures and the prevalence of team-based management in organizations,shared leadership which is horizontal,bottom-up and distributed among team members,has drawn much attention of researchers and practitioners.We first make clear the origins,concepts of shared leadership,its difference with other related concepts,and its measurement by systematically reviewing the existing literature of shared leadership.Then we clarify the fundamental theories about how shared leadership forms and summarize its em pirical studies.On this basis,we construct a theoretical model of shared leadership.Lastly,we summarize the managerial implications,limitations and future directions of shared leadership.%随着组织管理结构的扁平化以及团队管理的流行,共享型领导这一水平的、非正式的、分布于团队成员之间的集体领导力模式开始受到大量学者和管理者的关注.本文通过对现有共享型领导研究文献的系统梳理,明确了共享型领导的理论起源、概念内涵、与其他相关概念的区别和测量方法;了解了共享型领导形成的理论基础以及实证研究现状,并在此基础上构建了一个共享型领导的双元模型;最后提出了共享型领导对组织管理实践的启示,总结了现有研究的局限性以及未来的研究方向.

  17. Preoperative evaluation of hepatic arterial and portal venous anatomy using the time resolved echo-shared MR angiographic technique in living liver donors

    International Nuclear Information System (INIS)

    Lee, Min Woo; Lee, Jeong Min; Lee, Jae Young; Kim, Se Hyung; Park, Eun-Ah; Han, Joon Koo; Choi, Jin-Young; Choi, Byung Ihn; Kim, Young Jun; Suh, Kyung-Suk

    2007-01-01

    The purpose of this study was to determine whether MR angiography utilizing the time resolved echo-shared angiographic technique (TREAT) can provide an effective assessment of the hepatic artery (HA) and portal vein (PV) in living donor candidates. MR angiography (MRA)was performed in 27 patients (23 men and 4 women; mean age, 31 years) by using TREAT. Two blinded radiologists evaluated HA anatomy, origin of segment IV feeding artery and PV anatomy in consensus. Qualitative evaluations of MRA images were performed using the following criteria: (a) overall image quality, (b) presence of artifacts, and (c) degree of venous contamination of the arterial phase. Using intraoperative findings as a standard of reference, the accuracy for the HA anatomy, origin of segment IV feeding artery and PV anatomy on TREAT-MRA were 93% (25/27), 85% (23/27), and 96% (26/27), respectively. Overall image qualities were as follows: excellent (n=22, 81%), good (n=4, 15%), and fair (n=1, 4%). Significant artifacts or venous contamination of the arterial phase images was not noted in any patient. TREAT-MRA can provide a complete evaluation of HA and PV anatomy during preoperative evaluation of living liver donors. Furthermore, it provides a more detailed anatomy of the HA without venous contamination. (orig.)

  18. From interatomic interaction potentials via Einstein field equation techniques to time dependent contact mechanics

    International Nuclear Information System (INIS)

    Schwarzer, N

    2014-01-01

    In order to understand the principle differences between rheological or simple stress tests like the uniaxial tensile test to contact mechanical tests and the differences between quasistatic contact experiments and oscillatory ones, this study resorts to effective first principles. This study will show how relatively simple models simulating bond interactions in solids using effective potentials like Lennard-Jones and Morse can be used to investigate the effect of time dependent stress-induced softening or stiffening of these solids. The usefulness of the current study is in the possibility of deriving relatively simple dependences of the bulk-modulus B on time, shear and pressure P with time t. In cases where it is possible to describe, or at least partially describe a material by Lennard-Jones potential approaches, the above- mentioned dependences are even completely free of microscopic material parameters. Instead of bond energies and length, only specific integral parameters like Young’s modulus and Poisson’s ratio are required. However, in the case of time dependent (viscose) material behavior the parameters are not constants anymore. They themselves depend on time and the actual stress field, especially the shear field. A body completely consisting of so called standard linear solid interacting particles will then phenomenologically show a completely different and usually much more complicated mechanical behavior. The influence of the time dependent pressure-shear-induced Young’s modulus change is discussed with respect to mechanical contact experiments and their analysis in the case of viscose materials. (papers)

  19. Extending a real-time operating system with a mechanism for criticality-level changes

    NARCIS (Netherlands)

    Gupta, T.

    2015-01-01

    Systems robustness, cost reduction and certification play an important role in the automotive domain. If there is a fault, e.g. task overshooting its allocated execution time, sufficient mechanisms should be available to safeguard the system against those. Applications of different criticalities

  20. Math modeling and computer mechanization for real time simulation of rotary-wing aircraft

    Science.gov (United States)

    Howe, R. M.

    1979-01-01

    Mathematical modeling and computer mechanization for real time simulation of rotary wing aircraft is discussed. Error analysis in the digital simulation of dynamic systems, such as rotary wing aircraft is described. The method for digital simulation of nonlinearities with discontinuities, such as exist in typical flight control systems and rotor blade hinges, is discussed.

  1. On the relation between texture perception and fundamental mechanical parameters for liquids and time dependent solids

    NARCIS (Netherlands)

    Vliet, van T.

    2002-01-01

    Abstract Aspects of the relationship between texture perception in the mouth and fundamental mechanical parameters for liquids and time dependent solids are discussed. The emphasis is on the physical side of the relation. The importance is stressed of the incorporation of a thorough knowledge of

  2. Pricing mechanism for real-time balancing in regional electricity markets

    NARCIS (Netherlands)

    De Weerdt, M.M.; Ketter, W.; Collins, J.

    2011-01-01

    We consider the problem of designing a pricing mechanism for precisely controlling the real-time balance in electricity markets, where retail brokers aggregate the supply and demand of a number of individual customers, and must purchase or sell power at the wholesale level such that the total supply

  3. Numerical modelling of the time-dependent mechanical behaviour of softwood

    DEFF Research Database (Denmark)

    Engelund, Emil Tang

    2010-01-01

    When using wood as a structural material it is important to consider its time-dependent mechanical behaviour and to predict this behaviour for decades ahead. For this purpose, several rheological mathematical models, spanning from fairly simple to very complex ones, have been developed over...

  4. Neural Mechanisms of Interference Control and Time Discrimination in Attention-Deficit/Hyperactivity Disorder

    Science.gov (United States)

    Vloet, Timo D.; Gilsbach, Susanne; Neufang, Susanne; Fink, Gereon R.; Herpertz-Dahlmann, Beate; Konrad, Kerstin

    2010-01-01

    Objective: Both executive functions and time perception are typically impaired in subjects with attention-deficit/hyperactivity disorder (ADHD). However, the exact neural mechanisms underlying these deficits remain to be investigated. Method: Fourteen subjects with ADHD and 14 age- and IQ-matched controls (aged 9 through 15 years) were assessed…

  5. Shared Authentic Leadership in Research Teams: Testing a Multiple Mediation Model

    NARCIS (Netherlands)

    Günter, Hannes; Gardner, William L.; Davis McCauley, Kelly; Randolph-Seng, Brandon; P. Prahbu, Veena

    2017-01-01

    Research teams face complex leadership and coordination challenges. We propose shared authentic leadership (SAL) as a timely approach to addressing these challenges. Drawing from authentic and functional leadership theories, we posit a multiple mediation model that suggests three mechanisms whereby

  6. Mechanics and Newton-Cartan-like gravity on the Newton-Hooke space-time

    International Nuclear Information System (INIS)

    Tian Yu; Guo Hanying; Huang Chaoguang; Xu Zhan; Zhou Bin

    2005-01-01

    We focus on the dynamical aspects on Newton-Hooke space-time NH + mainly from the viewpoint of geometric contraction of the de Sitter spacetime with Beltrami metric. (The term spacetime is used to denote a space with non-degenerate metric, while the term space-time is used to denote a space with degenerate metric.) We first discuss the Newton-Hooke classical mechanics, especially the continuous medium mechanics, in this framework. Then, we establish a consistent theory of gravity on the Newton-Hooke space-time as a kind of Newton-Cartan-like theory, parallel to the Newton's gravity in the Galilei space-time. Finally, we give the Newton-Hooke invariant Schroedinger equation from the geometric contraction, where we can relate the conservative probability in some sense to the mass density in the Newton-Hooke continuous medium mechanics. Similar consideration may apply to the Newton-Hooke space-time NH - contracted from anti-de Sitter spacetime

  7. Gradient plasticity for thermo-mechanical processes in metals with length and time scales

    Science.gov (United States)

    Voyiadjis, George Z.; Faghihi, Danial

    2013-03-01

    A thermodynamically consistent framework is developed in order to characterize the mechanical and thermal behavior of metals in small volume and on the fast transient time. In this regard, an enhanced gradient plasticity theory is coupled with the application of a micromorphic approach to the temperature variable. A physically based yield function based on the concept of thermal activation energy and the dislocation interaction mechanisms including nonlinear hardening is taken into consideration in the derivation. The effect of the material microstructural interface between two materials is also incorporated in the formulation with both temperature and rate effects. In order to accurately address the strengthening and hardening mechanisms, the theory is developed based on the decomposition of the mechanical state variables into energetic and dissipative counterparts which endowed the constitutive equations to have both energetic and dissipative gradient length scales for the bulk material and the interface. Moreover, the microstructural interaction effect in the fast transient process is addressed by incorporating two time scales into the microscopic heat equation. The numerical example of thin film on elastic substrate or a single phase bicrystal under uniform tension is addressed here. The effects of individual counterparts of the framework on the thermal and mechanical responses are investigated. The model is also compared with experimental results.

  8. Job sharing: a viable option for the clinical nurse specialist.

    Science.gov (United States)

    Haibeck, S V; Howard, J L

    1991-01-01

    NUMEROUS WORK TIME options have been developed to attract, retain and meet the various needs of nurses. Job sharing, a work option little known to nurses, can be a successful alternative for balancing professional and personal lifestyle. The business literature supports job sharing and other innovative work options as successful mechanisms in retaining quality employees in their respective professions. After exploring the literature in this area, a proposal for job sharing the oncology clinical nurse specialist (CNS) position was presented to the Personnel Director and Vice President of Nursing at our institution. The proposal addressed the advantages and disadvantages of the concept. These included: (1) scheduling flexibility, (2) reduced absenteeism and turnover, (3) increased productivity, (4) handling fringe benefits, and (5) job satisfaction. The proposal was accepted, and the job sharing position has been successfully implemented for more than 2 years now. This paper describes issues relevant to designing and implementing job sharing in a CNS position.

  9. Instant Social Ride-Sharing

    OpenAIRE

    Gidofalvi, Gyözö; Herenyi, Gergely; Bach Pedersen, Torben

    2008-01-01

    This paper explores the use of ride–sharing as a resource-efficient mode of personal transportation. While the perceived benefits of ride–sharing include reduced travel times, transportation costs, congestion, and carbon emissions, its wide–spread adoption is hindered by a number of barriers. These include the scheduling and coordination of routes, safety risks, social discomfort in sharing private spaces, and an imbalance of costs and benefits among parties. To address these barriers, the au...

  10. Impact of Interlayer Dwell Time on Microstructure and Mechanical Properties of Nickel and Titanium Alloys

    Science.gov (United States)

    Foster, B. K.; Beese, A. M.; Keist, J. S.; McHale, E. T.; Palmer, T. A.

    2017-09-01

    Path planning in additive manufacturing (AM) processes has an impact on the thermal histories experienced at discrete locations in simple and complex AM structures. One component of path planning in directed energy deposition is the time required for the laser or heat source to return to a given location to add another layer of material. As structures become larger and more complex, the length of this interlayer dwell time can significantly impact the resulting thermal histories. The impact of varying dwell times between 0 and 40 seconds on the microstructural and mechanical properties of Inconel® 625 and Ti-6Al-4V builds has been characterized. Even though these materials display different microstructures and solid-state phase transformations, the addition of an interlayer dwell generally led to a finer microstructure in both materials that impacted the resulting mechanical properties. With the addition of interlayer dwell times up to 40 seconds in the Inconel® 625 builds, finer secondary dendrite arm spacing values, produced by changes in the thermal history, correspond to increased yield and tensile strengths. These mechanical properties did not appear to change significantly, however, for dwell times greater than 20 seconds in the Inconel® 625 builds, indicating that longer dwell times have a minimal impact. The addition of interlayer dwell times in Ti-6Al-4V builds resulted in a slight decrease in the measured alpha lath widths and a much more noticeable decrease in the width of prior beta grains. In addition, the yield and tensile values continued to increase, nearly reaching the values observed in the rolled plate substrate material with dwell times up to 40 seconds.

  11. Shared decision making

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000877.htm Shared decision making To use the sharing features on this page, ... treatment you both support. When to use Shared Decision Making Shared decision making is often used when you ...

  12. Sharing Death

    DEFF Research Database (Denmark)

    Sandvik, Kjetil; Refslund Christensen, Dorthe

    This paper examines the demarcation of space and time and the materiality of Mindet.dk as a designated place with its own (social) rules; a place for performing grief and segregating it from other aspects of social life. By logging in, the individuals step into the sacred space where they can spe...

  13. Absolute symbolic addressing, a structure making time-sharing easier; Adressage symbolique absolu, structure facilitant le travail en partage de temps

    Energy Technology Data Exchange (ETDEWEB)

    Debraine, P [Commissariat a l' Energie Atomique, 91 - Saclay (France). Centre d' Etudes Nucleaires, services scientifiques

    1968-08-01

    Time-sharing of computers asks for a certain number of conditions, particularly, an efficient dynamic loading of programs and data. This paper indicates a paging method making linkages with a minimum of table-looking operations. The principle is to use associative memory registers for calling blocks of physical memory, the block address being given by the concatenation of a file number (located in a base register) and a page number (located in the instruction proper). The position within the block is given by a displacement located in the instruction. A second associated base register contains the local part (page number + displacement) of the base address. This extended base register system allows executing programs in a very large programming complex without loss of time. The addresses are fixed at assembly time and the blocks can be loaded anywhere without modification for execution. The various problems associated with the execution of complex programs are presented in this context and shown to be easily solved by the proposed system, the realization of which would be very easy starting from the computer structures existing now. (author) [French] Le partage de temps des ordinateurs demande la realisation d'un certain nombre de conditions, en particulier, un chargement dynamique efficace des programmes et des donnees. Cet article indique une methode de pagination realisant les liaisons avec un minimum de consultations de tables. Le principe consiste a utiliser une memoire associative composee de registres pour appeler les blocs de la memoire physique, l'adresse de bloc etant donnee par concatenation d'un no de fichier (loge dans un registre de base) et d'un no de page (loge dans l'instruction proprement dite). La position a l'interieur du bloc est donnee par un deplacement loge dans l'instruction. Un second registre de base, associe au premier, contient la partie locale (no de page + deplacement) de l'adresse de base. Ce systeme d'extension de registre de base

  14. Comparing the effects of rise time and inspiratory cycling criteria on 6 different mechanical ventilators.

    Science.gov (United States)

    Gonzales, Joshua F; Russian, Christopher J; Gregg Marshall, S; Collins, Kevin P

    2013-03-01

    Inspiratory rise time and cycling criteria are important settings in pressure support ventilation. The purpose of this study was to investigate the impact of minimum and maximum rise time and inspiratory cycling criteria settings on 6 new generation ventilators. Our hypothesis was there would be a difference in the exhaled tidal volume, inspiratory time, and peak flow among 6 different ventilators, based, on change in rise time and cycling criteria. The research utilized a breathing simulator and 4 different ventilator models. All mechanical ventilators were set to a spontaneous mode of ventilation with settings of pressure support 8 cm H2O and PEEP of 5 cm H2O. A minimum and maximum setting for rise time and cycling criteria were examined. Exhaled tidal volume, inspiratory time, and peak flow measurements were recorded for each simulation. Significant (P ventilator. Significant differences in exhaled tidal volume, inspiratory time, and peak flow were observed by adjusting rise time and cycling criteria. This research demonstrates that during pressure support ventilation strategy, adjustments in rise time and/or cycling criteria can produce changes in inspiratory parameters. Obviously, this finding has important implications for practitioners who utilize a similar pressure support strategy when conducting a ventilator wean. Additionally, this study outlines major differences among ventilator manufacturers when considering inspiratory rise time and cycling criteria.

  15. Coupling Flux Towers and Networks with Proximal and Remote Sensing Data: New Tools to Collect and Share Time-Synchronized Hourly Fluxes

    Science.gov (United States)

    Burba, George; Avenson, Tom; Burkart, Andreas; Gamon, John; Guan, Kaiyu; Julitta, Tommaso; Pastorello, Gilberto; Sakowska, Karolina

    2017-04-01

    Multiple hundreds of flux towers are presently operational as standalone projects and as parts of larger networks. However, the vast majority of these towers do not allow straight-forward coupling with satellite data, and even fewer have optical sensors for validation of satellite products and upscaling from field to regional levels. In 2016, new tools to collect, process, and share time-synchronized flux data from multiple towers were developed and deployed globally. Originally designed to automate site and data management, these new tools can also be effective in coupling tower data with satellite data due to the following present capabilities: Fully automated FluxSuite system combines hardware, software and web-services, and does not require an expert to run it It can be incorporated into a new flux station or added to a present station, using weatherized remotely-accessible microcomputer, SmartFlux2 It utilizes EddyPro software to calculate fully-processed fluxes and footprints in near-realtime, alongside radiation, optical, weather and soil data All site data are merged into a single quality-controlled file timed using PTP time protocol Data from optical sensors can be integrated into this complete dataset via compatible dataloggers Multiple stations can be linked into time-synchronized network with automated reports and email alerts visible to PIs in real-time Remote sensing researchers without stations can form "virtual networks" of stations by collaborating with tower PIs from different physical networks The present system can then be utilized to couple ground data with satellite data via the following proposed concept: GPS-driven PTP protocol will synchronize instrumentation within the station, different stations with each other, and all of these to satellite data to precisely align optical and flux data in time Footprint size and coordinates computed and stored with flux data will help correctly align footprints and satellite motion to precisely align

  16. Life time estimation for irradiation assisted mechanical cracking of PWR RCCA rodlets

    Energy Technology Data Exchange (ETDEWEB)

    Matsuoka, Takanori; Yamaguchi, Youichirou [Nuclear Development Corp., Tokai, Ibaraki (Japan)

    1999-09-01

    Intergranular cracks of cladding tubes had been observed at the tips of the rodlets of PWR rod cluster control assemblies (RCCAs). Because RCCAs were important core components, an investigation was carried out to estimate their service lifetime. The reviews on their mechanism and the life time estimation are shown in this paper. The summaries are as follows. (1) The mechanism of the intergranular crack of the cladding tube was not IASCC but irradiation assisted mechanical cracking (IAMC) caused by an increase in hoop strain due to the swelling of the absorber and a decrease in elongation due to neutron irradiation. (2) The crack initiation limit of cylindrical shells made of low ductile material and subjected to internal pressure was determined in relation to the uniform strain of the material and was in accordance with that of the RCCA rodlets in an actual plant. (3) From the above investigation, the method of estimating the lifetime and countermeasures for its extension were obtained. (author)

  17. Job Sharing in the Public Sector.

    Science.gov (United States)

    Olmsted, Barney; And Others

    Job sharing is defined as "two people sharing the responsibilities of one full-time position with salary and benefits prorated"; the concept focuses on positions usually offered only as full-time jobs, often in professional and managerial categories. This book presents an overview of current job sharing and permanent part-time employment…

  18. An energy saving mechanism of EPON networks for real time video transmission

    Science.gov (United States)

    Liu, Chien-Ping; Wu, Ho-Ting; Chiang, Yun-Ting; Chien, Shieh-Chieh; Ke, Kai-Wei

    2015-07-01

    Modern access networks are constructed widely by passive optical networks (PONs) to meet the growing bandwidth demand. However, higher bandwidth means more energy consumption. To save energy, a few research works propose the dual-mode energy saving mechanism that allows the ONU to operate between active and sleep modes periodically. However, such dual-mode energy saving design may induce unnecessary power consumption or packet delay increase in the case where only downstream data exist for most of the time. In this paper, we propose a new tri-mode energy saving scheme for Ethernet PON (EPON). The new tri-mode energy saving design, combining the dual-mode saving mechanism with the doze mode, allows the ONU to switch among these three modes alternatively. In the doze mode, the ONU may receive downstream data while keeping its transmitter close. Such scenario is often observed for real time video downstream transmission. Furthermore, the low packet delay of high priority upstream data can be attained through the use of early wake-up mechanism employed in both energy saving modes. The energy saving and system efficiency can thus be achieved jointly while maintaining the differentiated QoS for data with various priorities. Performance results via simulation have demonstrated the effectiveness of such mechanism.

  19. Computation and Communication Evaluation of an Authentication Mechanism for Time-Triggered Networked Control Systems

    Science.gov (United States)

    Martins, Goncalo; Moondra, Arul; Dubey, Abhishek; Bhattacharjee, Anirban; Koutsoukos, Xenofon D.

    2016-01-01

    In modern networked control applications, confidentiality and integrity are important features to address in order to prevent against attacks. Moreover, network control systems are a fundamental part of the communication components of current cyber-physical systems (e.g., automotive communications). Many networked control systems employ Time-Triggered (TT) architectures that provide mechanisms enabling the exchange of precise and synchronous messages. TT systems have computation and communication constraints, and with the aim to enable secure communications in the network, it is important to evaluate the computational and communication overhead of implementing secure communication mechanisms. This paper presents a comprehensive analysis and evaluation of the effects of adding a Hash-based Message Authentication (HMAC) to TT networked control systems. The contributions of the paper include (1) the analysis and experimental validation of the communication overhead, as well as a scalability analysis that utilizes the experimental result for both wired and wireless platforms and (2) an experimental evaluation of the computational overhead of HMAC based on a kernel-level Linux implementation. An automotive application is used as an example, and the results show that it is feasible to implement a secure communication mechanism without interfering with the existing automotive controller execution times. The methods and results of the paper can be used for evaluating the performance impact of security mechanisms and, thus, for the design of secure wired and wireless TT networked control systems. PMID:27463718

  20. Hard and soft sub-time-optimal controllers for a mechanical system with uncertain mass

    DEFF Research Database (Denmark)

    Kulczycki, P.; Wisniewski, Rafal; Kowalski, P.

    2004-01-01

    An essential limitation in using the classical optimal control has been its limited robustness to modeling inadequacies and perturbations. This paper presents conceptions of two practical control structures based on the time-optimal approach: hard and soft ones. The hard structure is defined...... by parameters selected in accordance with the rules of the statistical decision theory; however, the soft structure allows additionally to eliminate rapid changes in control values. The object is a basic mechanical system, with uncertain (also non-stationary) mass treated as a stochastic process....... The methodology proposed here is of a universal nature and may easily be applied with respect to other elements of uncertainty of time-optimal controlled mechanical systems....

  1. Hard and soft Sub-Time-Optimal Controllers for a Mechanical System with Uncertain Mass

    DEFF Research Database (Denmark)

    Kulczycki, P.; Wisniewski, Rafal; Kowalski, P.

    2005-01-01

    An essential limitation in using the classical optimal control has been its limited robustness to modeling inadequacies and perturbations. This paper presents conceptions of two practical control structures based on the time-optimal approach: hard and soft ones. The hard structure is defined...... by parameters selected in accordance with the rules of the statistical decision theory; however, the soft structure allows additionally to eliminate rapid changes in control values. The object is a basic mechanical system, with uncertain (also non-stationary) mass treated as a stochastic process....... The methodology proposed here is of a universal nature and may easily be applied with respect to other elements of uncertainty of time-optimal controlled mechanical systems....

  2. Rotation stability of high speed neutron time-of-flight mechanical chopper

    International Nuclear Information System (INIS)

    Habib, N.; Adib, M.

    1998-01-01

    A modified rotation stabilization system has been designed to maintain the stability of a neutron time-of-flight (TOF) mechanical chopper rates from 460 rpm to 16000 rpm. The main principle of the system is based on comparing the chopper's rotation period with the preselected one from a quartz timer. The result of comparison is used to control the current driver of the chopper's motor. A 600 Hz three phase generator controlled by a magnetic amplifier was used as a current driver. The stability of the chopper's rotation rate at 16000 rpm was 0.02%. An improved method precise time scale calibration of the TOF spectrometer is applied

  3. A Time-Space Symmetry Based Cylindrical Model for Quantum Mechanical Interpretations

    Science.gov (United States)

    Vo Van, Thuan

    2017-12-01

    Following a bi-cylindrical model of geometrical dynamics, our study shows that a 6D-gravitational equation leads to geodesic description in an extended symmetrical time-space, which fits Hubble-like expansion on a microscopic scale. As a duality, the geodesic solution is mathematically equivalent to the basic Klein-Gordon-Fock equations of free massive elementary particles, in particular, the squared Dirac equations of leptons. The quantum indeterminism is proved to have originated from space-time curvatures. Interpretation of some important issues of quantum mechanical reality is carried out in comparison with the 5D space-time-matter theory. A solution of lepton mass hierarchy is proposed by extending to higher dimensional curvatures of time-like hyper-spherical surfaces than one of the cylindrical dynamical geometry. In a result, the reasonable charged lepton mass ratios have been calculated, which would be tested experimentally.

  4. Hydraulic mechanism and time-dependent characteristics of loose gully deposits failure induced by rainfall

    Directory of Open Access Journals (Sweden)

    Yong Wu

    2015-12-01

    Full Text Available Failure of loose gully deposits under the effect of rainfall contributes to the potential risk of debris flow. In the past decades, researches on hydraulic mechanism and time-dependent characteristics of loose deposits failure are frequently reported, however adequate measures for reducing debris flow are not available practically. In this context, a time-dependent model was established to determine the changes of water table of loose deposits using hydraulic and topographic theories. In addition, the variation in water table with elapsed time was analyzed. The formulas for calculating hydrodynamic and hydrostatic pressures on each strip and block unit of deposit were proposed, and the slope stability and failure risk of the loose deposits were assessed based on the time-dependent hydraulic characteristics of established model. Finally, the failure mechanism of deposits based on infinite slope theory was illustrated, with an example, to calculate sliding force, anti-sliding force and residual sliding force applied to each slice. The results indicate that failure of gully deposits under the effect of rainfall is the result of continuously increasing hydraulic pressure and water table. The time-dependent characteristics of loose deposit failure are determined by the factors of hydraulic properties, drainage area of interest, rainfall pattern, rainfall duration and intensity.

  5. The Clinical Utilisation of Respiratory Elastance Software (CURE Soft): a bedside software for real-time respiratory mechanics monitoring and mechanical ventilation management.

    Science.gov (United States)

    Szlavecz, Akos; Chiew, Yeong Shiong; Redmond, Daniel; Beatson, Alex; Glassenbury, Daniel; Corbett, Simon; Major, Vincent; Pretty, Christopher; Shaw, Geoffrey M; Benyo, Balazs; Desaive, Thomas; Chase, J Geoffrey

    2014-09-30

    Real-time patient respiratory mechanics estimation can be used to guide mechanical ventilation settings, particularly, positive end-expiratory pressure (PEEP). This work presents a software, Clinical Utilisation of Respiratory Elastance (CURE Soft), using a time-varying respiratory elastance model to offer this ability to aid in mechanical ventilation treatment. CURE Soft is a desktop application developed in JAVA. It has two modes of operation, 1) Online real-time monitoring decision support and, 2) Offline for user education purposes, auditing, or reviewing patient care. The CURE Soft has been tested in mechanically ventilated patients with respiratory failure. The clinical protocol, software testing and use of the data were approved by the New Zealand Southern Regional Ethics Committee. Using CURE Soft, patient's respiratory mechanics response to treatment and clinical protocol were monitored. Results showed that the patient's respiratory elastance (Stiffness) changed with the use of muscle relaxants, and responded differently to ventilator settings. This information can be used to guide mechanical ventilation therapy and titrate optimal ventilator PEEP. CURE Soft enables real-time calculation of model-based respiratory mechanics for mechanically ventilated patients. Results showed that the system is able to provide detailed, previously unavailable information on patient-specific respiratory mechanics and response to therapy in real-time. The additional insight available to clinicians provides the potential for improved decision-making, and thus improved patient care and outcomes.

  6. Designing for Sharing in Local Communities

    DEFF Research Database (Denmark)

    Malmborg, Lone; Light, Ann; Fitzpatrick, Geraldine

    2015-01-01

    The Sharing Economy has brought new attention to the everyday practice of sharing. Digital tools are changing both what we can do together across neighbourhoods and how we think about sharing our time, materials and skills. It is possible to design to boost resource management, economic wellbeing...... and social resilience by fostering sharing practices, but do different designs speak to different priorities in design for sharing?...

  7. Study on a new type variable valve lift timing mechanism with a three dimensional cam; Sanjigen cam ni yoru shinkahen valve lift timing kiko ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Ogura, M; Song, C [Nippon Institute of Technology, Saitama (Japan)

    1997-10-01

    The variable valve timing mechanism was invented to get a torque band at wide engine speed, and to reduce a compression job and pumping loss by a miler cycle at partial load. In this paper, the new type variable valve timing mechanism applying a three dimensional cam was proposed. Also, the feature of mechanism and the control system was done obviously. Further, about a miler cycle, a thermodynamics -like consideration was described. 5 refs., 8 figs.

  8. Time with friends and physical activity as mechanisms linking obesity and television viewing among youth.

    Science.gov (United States)

    Vandewater, Elizabeth A; Park, Seoung Eun; Hébert, Emily T; Cummings, Hope M

    2015-07-27

    Though bivariate relationships between childhood obesity, physical activity, friendships and television viewing are well documented, empirical assessment of the extent to which links between obesity and television may be mediated by these factors is scarce. This study examines the possibility that time with friends and physical activity are potential mechanisms linking overweight/obesity to television viewing in youth. Data were drawn from children ages 10-18 years old (M = 13.81, SD = 2.55) participating in the 2002 wave of Child Development Supplement (CDS) to the Panel Study of Income Dynamics (PSID) (n = 1,545). Data were collected both directly and via self-report from children and their parents. Path analysis was employed to examine a model whereby the relationships between youth overweight/obesity and television viewing were mediated by time spent with friends and moderate-to-vigorous physical activity (MVPA). Overweight/obesity was directly related to less time spent with friends, but not to MVPA. Time spent with friends was directly and positively related to MVPA, and directly and negatively related to time spent watching television without friends. In turn, MVPA was directly and negatively related to watching television without friends. There were significant indirect effects of both overweight/obesity and time with friends on television viewing through MVPA, and of overweight/obesity on MVPA through time with friends. Net of any indirect effects, the direct effect of overweight/obesity on television viewing remained. The final model fit the data extremely well (χ2 = 5.77, df = 5, ptelevision viewing in youth. These findings highlight the importance of moving from examinations of bivariate relationships between weight status and television viewing to more nuanced explanatory models which attempt to identify and unpack the possible mechanisms linking them.

  9. Active sharing

    CERN Multimedia

    2012-01-01

    The big news this week is, of course, the conclusions from the LHC performance workshop held in Chamonix from 6 to 10 February . The main recommendation, endorsed by CERN’s Machine Advisory Committee and adopted by the Management, is that the LHC will run at 4 TeV per beam this year. You can find all the details from Chamonix in the slides presented on Wednesday at the summary session, which leaves me free to talk about another important development coming up soon.   In ten days time, a new kind of gathering will be taking place in Geneva, bringing together two previously separate conferences, one driven by physics, the other by the medical community, but both looking to apply physics to the advancement of health. The merger of the International Conference for Translational Research in Radio-Oncology and CERN’s workshop on Physics for Health in Europe (ICTR-PHE) makes for a very eclectic mix. Presentations range from active shielding for interplanetary flight to the rather...

  10. Staffing Alternatives: Use of Retired Persons, Flex-Time, Job Sharing and Other Suggestions. Suggested Personnel Policy Guidelines for School Districts. [Revised].

    Science.gov (United States)

    Oregon State Dept. of Education, Salem.

    This report addresses three alternatives in employing certified and classified staff in school districts: early retirement, flexible working hours, and (in the most detail) job sharing. It is noted that financial reductions make it difficult for schools to meet both their budgets and rising community/parental expectations, while declining…

  11. Data forwarding mechanism for supporting real-time services during relocations in UMTS systems

    Science.gov (United States)

    Cai, Wei; Liao, Xianglong; Zheng, Liang; Liu, Zehong

    2004-04-01

    To minimize the interruption during the handovers or relocations invoked by subscribers moving is a very critical factor to enhance the performance of the UMTS systems. We know that the 2G systems have been optimized to minimize the interruption of speech during handovers by two main technologies: one is the bi-casting for the DL traffic and the other is the fast radio resynchronization by the UE for the UL traffic. In the UMTS systems, we have also implemented lossless relocations for non real-time services with high reliability by data buffering in the source RNC and target RNC for the UE. However, the UMTS systems support four QoS classes traffic flow: conversational class, streaming class, interactive class and background class. The main distinguishing factor between these QoS classes is how delay sensitive the traffic is: Conversational and Streaming classes are mainly used to carry real-time traffic flows, like video telephony, interactive and background classes are mainly used by traditional Internet applications like WWW, E-mail and FTP. It"s essential to provide the solutions for supporting real-time services to meet the requirement for QoS in UMTS systems. Apparently, the Data buffering mechanism is not adapted to real-time services because of it"s delay may exceed the basic requirement for real-time services. Under this background, the paper discussed two data forwarding solutions for real-time services from the PS domain in the UMTS systems: packet duplication and Core Network bi-casting. The former mechanism does not require any new procedures, messages nor information elements. The later mechanism requires that the GGSN or SGSN is able to bi-cast the DL traffic to the target RNC according to the relocations involving two SGSNs or just involving one SGSN. It also implicitly shows that we need change procedures at the nodes SGSN, GGSN and RNC which are involved in the relocation procedure based on existing procedures that we have already designed if

  12. One Share-One Vote

    DEFF Research Database (Denmark)

    Poulsen, Thomas; Eklund, Johan E.

    Shares with more voting rights than cash flow rights provide their owners with a disproportional influence that is often found to destroy the value of outside equity. This is taken as evidence of discretionary use of power. However, concentration of power does not necessarily result from control...... enhancing mechanisms; it could also be that some shareholders retain a large block in a one share-one vote structure. In this paper, we develop a methodology to disentangle disproportionality, which allows us to test the effect of deviations from one share-one vote more precisely. Our empirical findings add...

  13. [Influence of the occlusal interference time on masticatory muscle mechanical hyperalgesia in rats].

    Science.gov (United States)

    Liu, Cun-rui; Xu, Xiao-xiang; Cao, Ye; Xie, Qiu-fei

    2016-02-18

    To investigate the relationship between the removal time of 0.2 mm occlusal interference and the recovery of masticatory muscle mechanical hyperalgesia in rats. Forty male Sprague-Dawley rats (200-220 g) were randomly assigned to eight groups, with five rats in each group: (1) naive group: these rats were anesthetized and their mouths were forced open for about 5 min (the same duration as the other groups), but restorations were not applied; (2) sham-occlusal interference control group: bands were bonded to the right maxillary first molars which did not interfere with occlusion; (3)occlusal interference group: 0.2 mm thick crowns were bonded to the right maxillary first molars; (4) 2, 3, 4, 5, and 6 d removal of occlusal interference groups: 0.2 mm thick crowns were bonded to the right maxillary first molars and removed on days 2, 3, 4, 5, and 6. The naive group and sham-occlusal interference control group were control groups. The other groups were experimental groups. Bilateral masticatory muscle mechanical withdrawal thresholds were tested on pre-application days 1, 2, and 3, and on post-application days 1, 3, 5, 7, 10, 14, 21 and 28. The rats were weighed on pre-application day 1 and on post-application days 1, 2, 3, 4, 5, 6, and 7. Between the naive group and the sham-occlusal interference control group, there was no significant difference in the masticatory muscle mechanical withdrawal threshold of bilateral temporalis and masseters at each time point. No significant difference was detected between the contralateral side and ipsilateral side in experimental groups (P>0.05). In the 2, 3, 4, and 5 d removal of occlusal interference groups, the masticatory muscle mechanical withdrawal thresholds decreased after occlusal interference and increased after removal of the crowns and recovered to the baseline on days 7, 10, 14, and 14, respectively [the masticatory muscle mechanical withdrawal thresholds of right masseter muscle were (137.46 ± 2.08) g, (139.02 ± 2

  14. Effect of a disintegration mechanism on wetting, water absorption, and disintegration time of orodispersible tablets.

    Science.gov (United States)

    Pabari, Rm; Ramtoola, Z

    2012-07-01

    The aim of this study was to evaluate the influence of disintegration mechanism of various types of disintegrants on the absorption ratio (AR), wetting time (WT), and disintegration time (DT) of orodispersible tablets (ODTs). ODTs were prepared by direct compression using mannitol as filler and disintegrants selected from a range of swellable, osmotic, and porous disintegrants. Tablets formed were characterized for their water AR, WT, and DT. The porosity and mechanical strength of the tablets were also measured. Results show that the DT of formulated ODTs was directly related to the WT and was a function of the disintegration mechanism of the disintegrant used. The lowest WT and DT were observed for tablets formulated using the osmotic disintegrant sodium citrate and these tablets also showed the lowest AR and porosity. The wetting and disintegration of tablets containing the highly swellable disintegrant, sodium starch glycollate, was slowest despite their high water AR and high tablet porosity. Rapid wetting and disintegration of ODTs were therefore not necessarily related to the porosity of the tablets.

  15. Autoregressive Prediction with Rolling Mechanism for Time Series Forecasting with Small Sample Size

    Directory of Open Access Journals (Sweden)

    Zhihua Wang

    2014-01-01

    Full Text Available Reasonable prediction makes significant practical sense to stochastic and unstable time series analysis with small or limited sample size. Motivated by the rolling idea in grey theory and the practical relevance of very short-term forecasting or 1-step-ahead prediction, a novel autoregressive (AR prediction approach with rolling mechanism is proposed. In the modeling procedure, a new developed AR equation, which can be used to model nonstationary time series, is constructed in each prediction step. Meanwhile, the data window, for the next step ahead forecasting, rolls on by adding the most recent derived prediction result while deleting the first value of the former used sample data set. This rolling mechanism is an efficient technique for its advantages of improved forecasting accuracy, applicability in the case of limited and unstable data situations, and requirement of little computational effort. The general performance, influence of sample size, nonlinearity dynamic mechanism, and significance of the observed trends, as well as innovation variance, are illustrated and verified with Monte Carlo simulations. The proposed methodology is then applied to several practical data sets, including multiple building settlement sequences and two economic series.

  16. Possible mechanism of polyspermy block in human oocytes observed by time-lapse cinematography.

    Science.gov (United States)

    Mio, Yasuyuki; Iwata, Kyoko; Yumoto, Keitaro; Kai, Yoshiteru; Sargant, Haruka C; Mizoguchi, Chizuru; Ueda, Minako; Tsuchie, Yuka; Imajo, Akifumi; Iba, Yumiko; Nishikori, Kyoko

    2012-09-01

    To analyze the fertilization process related to polyspermy block in human oocytes using an in vitro culturing system for time-lapse cinematography. We had 122 oocytes donated for this study from couples that provided informed consent. We recorded human oocytes at 2,000 to 2,800 frames every 10 s during the fertilization process and thereafter every 2 min using a new in vitro culture system originally developed by the authors for time-lapse cinematography. We displayed 30 frames per second for analysis of the polyspermy block during fertilization. Three oocytes showed the leading and following sperm within the zona pellucida in the same microscopic field. The dynamic images obtained during the fertilization process using this new system revealed that once a leading sperm penetrated the zona pellucida and attached to the oocyte membrane, a following sperm was arrested from further penetration into the zona pellucida within 10 s. The present results strongly suggest the existence of a novel mechanism of polyspermy block that takes place at the zona pellucida immediately after fertilization. These findings are clearly different from previous mechanisms describing polyspermy block as the oocyte membrane block to sperm penetration and the zona reaction. The finding presented herein thus represents a novel discovery about the highly complicated polyspermy block mechanism occurring in human oocytes.

  17. Finding the Law for Sharing Data in Academia

    NARCIS (Netherlands)

    Hoorn, Esther; Domingus, Marlon; Schmidt, Birgit; Dobreva, Milena

    2015-01-01

    How can universities provide good advice about the legal aspects of research data management? At the same time, how can universities prevent that perceived legal risks become barriers to: conducting research, sharing research data, valorisation of research data, and control mechanisms for the

  18. Time-dependent convection study of the driving mechanism in the DBV white dwarfs

    International Nuclear Information System (INIS)

    Dupret, M A; Quirion, P O; Fontaine, G; Brassard, P; Grigahcene, A

    2008-01-01

    We apply for the first time time-dependent convection (TDC) models to the study of the driving mechanism of the Pulsating DB (V777 Herculis) white dwarfs. From the blue to the red edge of the instability strip of these stars, TDC appears to play a central role in the driving. Around the blue edge, the convection adapts quasi-instantaneously to the oscillations, so that TDC must be included in the models. For the first time, we show that the red edge of the DB instability strip is successfully obtained with a TDC treatment, especially thanks to the terms due to the turbulent pressure variations, while it is not reproduced with frozen convection models.

  19. Comment on ‘Overcoming misconceptions in quantum mechanics with the time evolution operator’

    International Nuclear Information System (INIS)

    Toyama, F M; Nogami, Y

    2013-01-01

    In their paper ‘Overcoming misconceptions in quantum mechanics with the time evolution operator’, García Quijas and Arévalo Aguilar (2007 Eur. J. Phys. 28 147) examined the time-dependent wave function of a particle in the one-dimensional harmonic oscillator potential using two different methods. The two wave functions that the authors obtained through the methods have different analytical expressions. The authors showed numerically that the two wave functions lead to the same probability density. When the real parts of the wave functions are compared, however, they are different in their details. That was puzzling because both wave functions are supposed to be solutions of the same time-dependent Schrödinger equation with the same initial condition. We point out that the two wave functions are actually identical. We show this analytically. (letters and comments)

  20. Time travel paradoxes, path integrals, and the many worlds interpretation of quantum mechanics

    International Nuclear Information System (INIS)

    Everett, Allen

    2004-01-01

    We consider two approaches to evading paradoxes in quantum mechanics with closed timelike curves. In a model similar to Politzer's, assuming pure states and using path integrals, we show that the problems of paradoxes and of unitarity violation are related; preserving unitarity avoids paradoxes by modifying the time evolution so that improbable events become certain. Deutsch has argued, using the density matrix, that paradoxes do not occur in the 'many worlds interpretation'. We find that in this approach account must be taken of the resolution time of the device that detects objects emerging from a wormhole or other time machine. When this is done one finds that this approach is viable only if macroscopic objects traversing a wormhole interact with it so strongly that they are broken into microscopic fragments

  1. Approximations of time-dependent phenomena in quantum mechanics: adiabatic versus sudden processes

    International Nuclear Information System (INIS)

    Melnichuk, S V; Dijk, W van; Nogami, Y

    2005-01-01

    By means of a one-dimensional model of a particle in an infinite square-well potential with one wall moving at a constant speed, we examine aspects of time-dependent phenomena in quantum mechanics such as adiabatic and sudden processes. The particle is assumed to be initially in the ground state of the potential with its initial width. The time dependence of the wavefunction of the particle in the well is generally more complicated when the potential well is compressed than when it is expanded. We are particularly interested in the case in which the potential well is suddenly compressed. The so-called sudden approximation is not applicable in this case. We also study the energy of the particle in the changing well as a function of time for expansion and contraction as well as for expansion followed by contraction and vice versa

  2. Real-time dynamics of matrix quantum mechanics beyond the classical approximation

    Science.gov (United States)

    Buividovich, Pavel; Hanada, Masanori; Schäfer, Andreas

    2018-03-01

    We describe a numerical method which allows to go beyond the classical approximation for the real-time dynamics of many-body systems by approximating the many-body Wigner function by the most general Gaussian function with time-dependent mean and dispersion. On a simple example of a classically chaotic system with two degrees of freedom we demonstrate that this Gaussian state approximation is accurate for significantly smaller field strengths and longer times than the classical one. Applying this approximation to matrix quantum mechanics, we demonstrate that the quantum Lyapunov exponents are in general smaller than their classical counterparts, and even seem to vanish below some temperature. This behavior resembles the finite-temperature phase transition which was found for this system in Monte-Carlo simulations, and ensures that the system does not violate the Maldacena-Shenker-Stanford bound λL < 2πT, which inevitably happens for classical dynamics at sufficiently small temperatures.

  3. From Discrete Space-Time to Minkowski Space: Basic Mechanisms, Methods and Perspectives

    Science.gov (United States)

    Finster, Felix

    This survey article reviews recent results on fermion systems in discrete space-time and corresponding systems in Minkowski space. After a basic introduction to the discrete setting, we explain a mechanism of spontaneous symmetry breaking which leads to the emergence of a discrete causal structure. As methods to study the transition between discrete space-time and Minkowski space, we describe a lattice model for a static and isotropic space-time, outline the analysis of regularization tails of vacuum Dirac sea configurations, and introduce a Lorentz invariant action for the masses of the Dirac seas. We mention the method of the continuum limit, which allows to analyze interacting systems. Open problems are discussed.

  4. General-Covariant Quantum Mechanics of Dirac Particle in Curved Space-Times

    International Nuclear Information System (INIS)

    Tagirov, Eh.A.

    1994-01-01

    A general covariant analog of the standard non-relativistic Quantum Mechanics with relativistic corrections in normal geodesic frames in the general Riemannian space-time is constructed for the Dirac particle. Not only the Pauli equation with hermitian Hamiltonian and the pre-Hilbert structure of space of its solutions but also the matrix elements of hermitian operators of momentum, (curvilinear) spatial coordinates and spin of the particle are deduced as general-covariant asymptotic approximation in c -2 , c being the velocity of light, to their naturally determined general-relativistic pre images. It is shown that the Hamiltonian in the Pauli equation originated by the Dirac equation is unitary equivalent to the operator of energy, originated by the metric energy-momentum tensor of the spinor field. Commutation and other properties of the observables connected with the considered change of geometrical background of Quantum Mechanics are briefly discussed. 7 refs

  5. Microstructural Evolution of Advanced Radiation-Resistant ODS Steel with Different Lengths of Mechanical Alloying Time

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Sanghoon; Kim, Ga Eon; Kang, Suk Hoon; Kim, Tae Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Austenitic stainless steel may be one of the candidates because of good strength and corrosion resistance at the high temperatures, however irradiation swelling well occurred to 120dpa at high temperatures and this leads the decrease of the mechanical properties and dimensional stability. Compared to this, ferritic/ martensitic steel is a good solution because of excellent thermal conductivity and good swelling resistance. Unfortunately, the available temperature range of ferritic/martensitic steel is limited up to 650 .deg. C. ODS steel is the most promising structural material because of excellent creep and irradiation resistance by uniformly distributed nano-oxide particles with a high density which is extremely stable at the high temperature in ferritic/martensitic matrix. In this study, powder properties and microstructures of the ODS steel with different length of mechanical alloying time was investigated. The ODS steel milled 5h showed homogeneous grain structure with the highest hardness.

  6. Microstructural Evolution of Advanced Radiation-Resistant ODS Steel with Different Lengths of Mechanical Alloying Time

    International Nuclear Information System (INIS)

    Noh, Sanghoon; Kim, Ga Eon; Kang, Suk Hoon; Kim, Tae Kyu

    2015-01-01

    Austenitic stainless steel may be one of the candidates because of good strength and corrosion resistance at the high temperatures, however irradiation swelling well occurred to 120dpa at high temperatures and this leads the decrease of the mechanical properties and dimensional stability. Compared to this, ferritic/ martensitic steel is a good solution because of excellent thermal conductivity and good swelling resistance. Unfortunately, the available temperature range of ferritic/martensitic steel is limited up to 650 .deg. C. ODS steel is the most promising structural material because of excellent creep and irradiation resistance by uniformly distributed nano-oxide particles with a high density which is extremely stable at the high temperature in ferritic/martensitic matrix. In this study, powder properties and microstructures of the ODS steel with different length of mechanical alloying time was investigated. The ODS steel milled 5h showed homogeneous grain structure with the highest hardness

  7. Chemical dynamics in the gas phase: Time-dependent quantum mechanics of chemical reactions

    Energy Technology Data Exchange (ETDEWEB)

    Gray, S.K. [Argonne National Laboratory, IL (United States)

    1993-12-01

    A major goal of this research is to obtain an understanding of the molecular reaction dynamics of three and four atom chemical reactions using numerically accurate quantum dynamics. This work involves: (i) the development and/or improvement of accurate quantum mechanical methods for the calculation and analysis of the properties of chemical reactions (e.g., rate constants and product distributions), and (ii) the determination of accurate dynamical results for selected chemical systems, which allow one to compare directly with experiment, determine the reliability of the underlying potential energy surfaces, and test the validity of approximate theories. This research emphasizes the use of recently developed time-dependent quantum mechanical methods, i.e. wave packet methods.

  8. PREFACE: The 395th Wilhelm and Else Heraeus Seminar: `Time-dependent phenomena in Quantum Mechanics'

    Science.gov (United States)

    Kleber, Manfred; Kramer, Tobias

    2008-03-01

    The 395th Wilhelm and Else Heraeus Seminar: `Time-dependent phenomena in Quantum Mechanics' took place at the Heinrich Fabri Institute in Blaubeuren, Germany, 12-16 September 2007. The conference covered a wide range of topics connected with time-dependent phenomena in quantum mechanical systems. The 20 invited talks and 15 short talks with posters at the workshop covered the historical debate between Schrödinger, Dirac and Pauli about the role of time in Quantum Mechanics (the debate was carried out sometimes in footnotes) up to the almost direct observation of electron dynamics on the attosecond time-scale. Semiclassical methods, time-delay, monodromy, variational principles and quasi-resonances are just some of the themes which are discussed in more detail in the papers. Time-dependent methods also shed new light on energy-dependent systems, where the detour of studying the time-evolution of a quantum states allows one to solve previously intractable problems. Additional information is available at the conference webpage http://www.quantumdynamics.de The organizer would like to thank all speakers, contributors, session chairs and referees for their efforts in making the conference a success. We also gratefully acknowledge the generous financial support from the Wilhelm and Else Heraeus Foundation for the conference and the production of this special volume of Journal of Physics: Conference Series. Manfred Kleber Physik Department T30, Technische Universität München, 85747 Garching, Germany mkleber@ph.tum.de Tobias Kramer Institut I: Theoretische Physik, Universität Regensburg, 93040 Regensburg, Germany tobias.kramer@physik.uni-regensburg.de Guest Editors Front row (from left): W Schleich, E J Heller, J B Delos, H Friedrich, K Richter, M Kleber, P Kramer, M Man'ko, A del Campo, V Man'ko, M Efremov, A Ruiz, M O Scully Middle row: A Zamora, R Aganoglu, T Kramer, J Eiglsperger, H Cruz, P Raab, I Cirac, G Muga, J Larson, V Dodonov, W Becker Back row: A Eckardt, A

  9. Stability of orbits in nonlinear mechanics for finite but very long times

    International Nuclear Information System (INIS)

    Warnock, R.L.; Ruth, R.D.

    1990-07-01

    In various applications of nonlinear mechanics, especially in accelerator design, it would be useful to set bounds on the motion for finite but very long times. Such bounds can be sought with the help of a canonical transformation to new action-angle variables (J, Ψ), such that action J is nearly constant while the angle Ψ advances almost linearly with the time. By examining the change in J during a time T 0 from many initial conditions in the open domain Ω of phase space, one can estimate the change in J during a much larger time T, on any orbit starting in a smaller open domain Ω 0 contained-in Ω. A numerical realization of this idea is described. The canonical transformations, equivalent to close approximations to invariant tori, are constructed by an effective new method in which surfaces are fitted to orbit data. In a first application to a model sextupole lattice in a region of strong nonlinearity, we predict stability of betatron motion in two degrees of freedom for a time comparable to the storage time in a proton storage ring (10 8 turns). 10 refs., 6 figs., 1 tab

  10. Stability of orbits in nonlinear mechanics for finite but very long times

    Energy Technology Data Exchange (ETDEWEB)

    Warnock, R.L.; Ruth, R.D.

    1990-07-01

    In various applications of nonlinear mechanics, especially in accelerator design, it would be useful to set bounds on the motion for finite but very long times. Such bounds can be sought with the help of a canonical transformation to new action-angle variables (J, {Psi}), such that action J is nearly constant while the angle {Psi} advances almost linearly with the time. By examining the change in J during a time T{sub 0} from many initial conditions in the open domain {Omega} of phase space, one can estimate the change in J during a much larger time T, on any orbit starting in a smaller open domain {Omega}{sub 0} {contained in} {Omega}. A numerical realization of this idea is described. The canonical transformations, equivalent to close approximations to invariant tori, are constructed by an effective new method in which surfaces are fitted to orbit data. In a first application to a model sextupole lattice in a region of strong nonlinearity, we predict stability of betatron motion in two degrees of freedom for a time comparable to the storage time in a proton storage ring (10{sup 8} turns). 10 refs., 6 figs., 1 tab.

  11. Neurocognitive Mechanisms of Prejudice Formation: The Role of Time-Dependent Memory Consolidation.

    Science.gov (United States)

    Enge, Luke R; Lupo, Amber K; Zárate, Michael A

    2015-07-01

    Prejudice is generally thought to derive from learned, emotion-laden experiences. The mechanisms underlying the formation of prejudice over time, however, remain unknown. In the present research, we proposed and tested hypotheses regarding prejudice formation derived from research on memory consolidation and social perception. We hypothesized that time-dependent memory consolidation would produce better implicit memory for negative out-group information and positive in-group information, compared with negative in-group information and positive out-group information. Fifty undergraduates learned positive and negative information about racial in-group (Latino) and out-group (African American) targets. Participants returned after both a short time delay (2-6 hr after the learning session) and a long time delay (48 hr after the learning session) to complete a lexical decision task. Results demonstrated that participants responded to information consistent with an in-group bias faster after a long time delay than after a short time delay. Our findings have important implications for the study of social perception and memory consolidation. © The Author(s) 2015.

  12. Time-dependent chemo-electro-mechanical behavior of hydrogel-based structures

    Science.gov (United States)

    Leichsenring, Peter; Wallmersperger, Thomas

    2018-03-01

    Charged hydrogels are ionic polymer gels and belong to the class of smart materials. These gels are multiphasic materials which consist of a solid phase, a fluid phase and an ionic phase. Due to the presence of bound charges these materials are stimuli-responsive to electrical or chemical loads. The application of electrical or chemical stimuli as well as mechanical loads lead to a viscoelastic response. On the macroscopic scale, the response is governed by a local reversible release or absorption of water which, in turn, leads to a local decrease or increase of mass and a respective volume change. Furthermore, the chemo-electro-mechanical equilibrium of a hydrogel depends on the chemical composition of the gel and the surrounding solution bath. Due to the presence of bound charges in the hydrogel, this system can be understood as an osmotic cell where differences in the concentration of mobile ions in the gel and solution domain lead to an osmotic pressure difference. In the present work, a continuum-based numerical model is presented in order to describe the time-dependent swelling behavior of hydrogels. The numerical model is based on the Theory of Porous Media and captures the fluid-solid, fluid-ion and ion-ion interactions. As a direct consequence of the chemo-electro-mechanical equilibrium, the corresponding boundary conditions are defined following the equilibrium conditions. For the interaction of the hydrogel with surrounding mechanical structures, also respective jump condtions are formulated. Finaly, numerical results of the time-dependent behavior of a hydrogel-based chemo-sensor will be presented.

  13. Compulsory acquisition of shares buyer, other shareholders, abuse of right of compulsory acquisition of shares

    Directory of Open Access Journals (Sweden)

    Arsić Zoran V.

    2015-01-01

    Full Text Available Company Act of Republic of Serbia includes mechanism for the compulsory acquisition of the shareholdings of minority shareholders. Technically this procedure is effected on the basis of the shareholders assembly resolution. Buyer is shareholder who has at least 90% of share capital and at least 90% of votes. Shares owned by entity under his dominant influence will be treated as shares of that shareholder provided that dominant influence exists at least one year. Company's own shares, and shares subject o a pledge do not represent shares of other shareholders. There are several actions which may be treated as abuse of right of compulsory acquisition of shares.

  14. Ontogenic timing mechanism initiates the expression of rat intestinal sucrase activity

    International Nuclear Information System (INIS)

    Yeh, K.Y.; Holt, P.R.

    1986-01-01

    Morphologic and enzymic differentiation occurs in rat small intestinal epithelium during 16-20 days of postnatal life. This change is considered to be initiated by an ontogenic timing mechanism and is modulated by extrinsic systemic and luminal factors. The importance of the ontogenic timing was tested directly using a transplantation technique in which jejunal isografts from newborn (day 0) and 5-day-old (day 5) rats were implanted under the skin of newborn (day 0) hosts. Isografts showing cryptvillus architecture were obtained in 44% and 21% of transplants, respectively. Day 0 isografts and host intestine expressed sucrase activity at about 16-18 days of age and showed similar crypt cell labeling and epithelial migration after [3H]thymidine injection. Day 5 isografts expressed sucrase activity when the hosts were 13 days of age, whereas host intestine showed no detectable sucrase activity. Isograft lactase activities in both experimental transplant models were significantly higher than host intestinal lactase up to 28 days of age, suggesting that luminal factors are important in modulating lactase activity during the first 4 wk of postnatal life. It is concluded that (a) no systemic factors at day 13 inhibit the expression of sucrase activity and (b) an ontogenic timing mechanism in the jejunum initiates the expression of sucrase activity

  15. Job sharing at the managerial level.

    Science.gov (United States)

    Acorn, S; Williams, J; Dempster, L; Provost, S; McEwan, C

    1997-05-01

    Job sharing restructures a full-time position-two individuals share the responsibilities and the benefits of the position. If nurses are committed to making it work, this arrangement can succeed at the managerial level.

  16. Optical Coherence Tomography (OCT for Time-Resolved Imaging of Alveolar Dynamics in Mechanically Ventilated Rats

    Directory of Open Access Journals (Sweden)

    Christian Schnabel

    2017-03-01

    Full Text Available Though artificial ventilation is an essential life-saving treatment, the mechanical behavior of lung tissue at the alveolar level is still unknown. Therefore, we need to understand the tissue response during artificial ventilation at this microscale in order to develop new and more protective ventilation methods. Optical coherence tomography (OCT combined with intravital microscopy (IVM is a promising tool for visualizing lung tissue dynamics with a high spatial and temporal resolution in uninterruptedly ventilated rats. We present a measurement setup using a custom-made animal ventilator and a gating technique for data acquisition of time-resolved sequences.

  17. Horizons and non-local time evolution of quantum mechanical systems

    International Nuclear Information System (INIS)

    Casadio, Roberto

    2015-01-01

    According to general relativity, trapping surfaces and horizons are classical causal structures that arise in systems with sharply defined energy and corresponding gravitational radius. The latter concept can be extended to a quantum mechanical matter state simply by means of the spectral decomposition, which allows one to define an associated ''horizon wave-function''. Since this auxiliary wave-function contains crucial information about the causal structure of space-time, a new proposal is formulated for the time evolution of quantum systems in order to account for the fundamental classical property that outer observers cannot receive signals from inside a horizon. The simple case of a massive free particle at rest is used throughout the paper as a toy model to illustrate the main ideas. (orig.)

  18. Theoretical treatment of photodissociation of water by time-dependent quantum mechanical methods

    International Nuclear Information System (INIS)

    Weide, K.

    1993-01-01

    An algorithm for wavepacket propagation, based on Kosloff's method of expansion of the time evolution operator in terms of Chebychev polynomials, and some details of its implementation are described. With the programs developed, quantum-mechanical calculations for up to three independent molecular coordinates are possible and feasible and therefore photodissociation of non-rotating triatomic molecules can be treated exactly. The angular degree of freedom here is handled by expansion in terms of free diatomic rotor states. The time-dependent wave packet picture is compared with the more traditional view of stationary wave functions, and both are used to interpret computational results where appropriate. Two-dimensional calculations have been performed to explain several experimental observations about water photodissociation. All calculations are based on ab initio potential energy surfaces, and it is explained in each case why it is reasonable to neglect the third degree of freedom. Many experimental results are reproduced quantitatively. (orig.) [de

  19. Effect of ageing time on mechanical properties of plasticized poly(hydroxybutyrate) (PHB)

    Science.gov (United States)

    Farris, Giuseppe; Cinelli, Patrizia; Anguillesi, Irene; Salvadori, Sara; Coltelli, Maria-Beatrice; Lazzeri, Andrea

    2014-05-01

    Polyhydroxybutyrate (PHB) based materials were prepared by melt extrusion by using different plasticizers, such as poly(ethylene glycol)s (PEG)s having different molecular weight (400, 1500 and 4000). The plasticizers content was varied in the range 10-20% by weight versus the PHB polymeric matrix. The variation of tensile properties of the different samples was monitored as a function of time of ageing to study the stability of the material. The elastic modulus and tensile strength increased as a function of time, whereas the strain at break decreased. The experimental results were explained by considering both the demixing of the plasticizers and the occurring of secondary crystallization. Moreover the variation in mechanical properties was correlated to the structure and concentration of the different plasticizers employed.

  20. SAFCM: A Security-Aware Feedback Control Mechanism for Distributed Real-Time Embedded Systems

    DEFF Research Database (Denmark)

    Ma, Yue; Jiang, Wei; Sang, Nan

    2012-01-01

    Distributed Real-time Embedded (DRE) systems are facing great challenges in networked, unpredictable and especially unsecured environments. In such systems, there is a strong need to enforce security on distributed computing nodes in order to guard against potential threats, while satisfying......-time systems, a multi-input multi-output feedback loop is designed and a model predictive controller is deployed based on an equation model that describes the dynamic behavior of the DRE systems. This control loop uses security level scaling to globally control the CPU utilization and security performance...... for the whole system. We propose a "security level" metric based on an evolution of cryptography algorithms used in embedded systems. Experimental results demonstrate that SAFCM not only has the excellent adaptivity compared to open-loop mechanism, but also has a better overall performance than PID control...

  1. Time dependency in the mechanical properties of crystalline rocks. A literature survey

    International Nuclear Information System (INIS)

    Hagros, A.; Johansson, E.; Hudson, J.A.

    2008-09-01

    Because of the long design life, elevated temperatures, and the location at depth (high stresses), time-dependent aspects of the mechanical properties of crystalline rock are potentially important for the design and the long term safety of the radioactive waste repository at Olkiluoto. However, time-dependent effects in rock mechanics are still one of the least understood aspects of the physical behaviour of rock masses, this being partly due to the fact that it is difficult to conduct long-term experimental tests - either in the laboratory or in situ. Yet, the time-dependent mechanical behaviour needs to be characterised so that it can be included in the modelling studies supporting repository design. The Introduction explains the background to the literature survey and includes definitions of the terms 'creep' (increasing strain at constant stress) and 'stress relaxation' (decreasing stress at constant strain). Moreover, it is noted that the rock around an in situ excavation is loaded by the adjacent rock elements and so the timedependent behaviour will depend on the unloading stiffness of these and hence will not actually be either pure creep or pure stress relaxation. The Appendix contains the results of the literature survey of reported time-dependent research as it applies to crystalline rock. A summary of each of the 38 literature items is presented in tabular form covering document number, subject area, document reference, subject matter, objectives, methodology, highlighted figures, conclusions and comments. It is concluded that the time-dependent failure strength of all rocks observed may be interpreted by sub-critical crack growth assisted by the stress corrosion mechanism. Also, certain parameters are known to affect the long-term properties: mineralogy, grain size, water/water chemistry, confining stress and loading history. At some point in the loading history of rock, the state of crack development reaches a point whereby the continued generation of

  2. Paralinguistic mechanisms of production in human "beatboxing": a real-time magnetic resonance imaging study.

    Science.gov (United States)

    Proctor, Michael; Bresch, Erik; Byrd, Dani; Nayak, Krishna; Narayanan, Shrikanth

    2013-02-01

    Real-time magnetic resonance imaging (rtMRI) was used to examine mechanisms of sound production by an American male beatbox artist. rtMRI was found to be a useful modality with which to study this form of sound production, providing a global dynamic view of the midsagittal vocal tract at frame rates sufficient to observe the movement and coordination of critical articulators. The subject's repertoire included percussion elements generated using a wide range of articulatory and airstream mechanisms. Many of the same mechanisms observed in human speech production were exploited for musical effect, including patterns of articulation that do not occur in the phonologies of the artist's native languages: ejectives and clicks. The data offer insights into the paralinguistic use of phonetic primitives and the ways in which they are coordinated in this style of musical performance. A unified formalism for describing both musical and phonetic dimensions of human vocal percussion performance is proposed. Audio and video data illustrating production and orchestration of beatboxing sound effects are provided in a companion annotated corpus.

  3. Mechanical & morphological properties of attapulgite/NR composites: Effect of mixing time variation

    Energy Technology Data Exchange (ETDEWEB)

    Nor, Nor Aina Mohd, E-mail: ayena90@yahoo.com; Othman, Nadras, E-mail: srnadras@usm.my; Ismail, Hanafi, E-mail: ihanafi@usm.my [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, 14300 Nibong Tebal, Pulau Pinang (Malaysia)

    2015-07-22

    The development of composite material based on attapulgite clay (ATP) as a filler and natural rubber (NR) matrices were prepared by combination of melt mixing and latex compounding methods. Sonication technique was chosen in this work to disperse the attapulgite suspension. 6 phr of attapulgite loading was fabricated using different time of mixing ranging from 30 minutes until 2 hours and sonication time was kept constant at 15 minutes. Then, co-coagulating HA latex with attapulgite clay suspension through latex compounding method produced the masterbatch. The masterbatch was compounded with natural rubber by melt mixing method. The mechanical and morphological characteristics were investigated in this work. From mechanical testing, M1 showed the highest value of tensile and tear strength. By comparing with M30 and M2, M1 shows high 300% tensile modulus and lower crosslink density. However, when the time of mixing was prolonged to 2 hours, the results for tensile strength, elongation at break and tear strength were decreased. This is due to flocculation of attapulgite particles. Sonication techniques also proved that the tensile strength and elongation at break of these three samples were higher compared to gum NR (NR) and attapulgite compounded with NR using a conventional method (in-situ 6). From field emission scanning electron microscope (FESEM) results, it revealed that M1 had good dispersion in the NR system. It is proved that the higher tensile strength was due to good dispersion of attapulgite clay in the NR matrix. It was also supported from crosslink density, which is lower than NR and in-situ 6 results. It showed that the penetration of toluene solvent into rubber compound was restricted. The optimum time, M1 give the best results, which can be compared to control the sample.

  4. Mechanical & morphological properties of attapulgite/NR composites: Effect of mixing time variation

    International Nuclear Information System (INIS)

    Nor, Nor Aina Mohd; Othman, Nadras; Ismail, Hanafi

    2015-01-01

    The development of composite material based on attapulgite clay (ATP) as a filler and natural rubber (NR) matrices were prepared by combination of melt mixing and latex compounding methods. Sonication technique was chosen in this work to disperse the attapulgite suspension. 6 phr of attapulgite loading was fabricated using different time of mixing ranging from 30 minutes until 2 hours and sonication time was kept constant at 15 minutes. Then, co-coagulating HA latex with attapulgite clay suspension through latex compounding method produced the masterbatch. The masterbatch was compounded with natural rubber by melt mixing method. The mechanical and morphological characteristics were investigated in this work. From mechanical testing, M1 showed the highest value of tensile and tear strength. By comparing with M30 and M2, M1 shows high 300% tensile modulus and lower crosslink density. However, when the time of mixing was prolonged to 2 hours, the results for tensile strength, elongation at break and tear strength were decreased. This is due to flocculation of attapulgite particles. Sonication techniques also proved that the tensile strength and elongation at break of these three samples were higher compared to gum NR (NR) and attapulgite compounded with NR using a conventional method (in-situ 6). From field emission scanning electron microscope (FESEM) results, it revealed that M1 had good dispersion in the NR system. It is proved that the higher tensile strength was due to good dispersion of attapulgite clay in the NR matrix. It was also supported from crosslink density, which is lower than NR and in-situ 6 results. It showed that the penetration of toluene solvent into rubber compound was restricted. The optimum time, M1 give the best results, which can be compared to control the sample

  5. Introduction of a quantum of time ('chronon') and its consequences for quantum mechanics

    International Nuclear Information System (INIS)

    Farias, R.H.A.; Recami, E.; INFN, Milan; Campinas, State University, SP

    1998-01-01

    The authors discuss the consequences of the introduction of a quantum of time τ 0 in the formalism of non-relativistic quantum mechanics, by referring themselves in particular to the theory of the chronon as proposed by P. Caldirola. Such an interesting 'finite difference' theory, forwards -at the classical level- a solution for the motion of a particle endowed with a non-negligible charge in an external electromagnetic field, overcoming all the known difficulties met by Abraham-Lorentz's and Dirac's approaches (and even allowing a clear answer to the question whether a free falling charged particle does or not emit radiation), and -at the quantum level- yields a remarkable mass spectrum for leptons. After having briefly reviewed Caldirola's approach, the first aim of the authors is to work out, discuss, and compare one another the mew representations of Quantum Mechanics (QM) resulting from it, in the Schroedinger, Heisenberg and density-operator (Liouville-von Neumann) pictures, respectively.The authors also obtain the (retarded) finite-difference Schroedinger equation within the Feynman path integral approach, and study some of its relevant solutions. They, then, derive the time-evolution operators of this discrete theory, and use them to get the finite-difference Heisenberg equations. At last, the density matrix formalism is applied to the solution of the measurement problem in QM, with very interesting results, so as a natural explication of 'decoherence', which reveal the power of dicretized (in particular, retarded) QM

  6. Introduction of a quantum of time (`chronon`) and its consequences for quantum mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Farias, R.H.A. [Lab. Nacional de Luz Sincrotron, Campinas, SP (Brazil); Recami, E. [Bergamo Univ. (Italy). Fac. di Ingegneria]|[INFN, Milan (Italy)]|[Campinas, State University, SP (Brazil). DMO-FEEC, CCS

    1998-12-31

    The authors discuss the consequences of the introduction of a quantum of time {tau}{sub 0} in the formalism of non-relativistic quantum mechanics, by referring themselves in particular to the theory of the chronon as proposed by P. Caldirola. Such an interesting `finite difference` theory, forwards -at the classical level- a solution for the motion of a particle endowed with a non-negligible charge in an external electromagnetic field, overcoming all the known difficulties met by Abraham-Lorentz`s and Dirac`s approaches (and even allowing a clear answer to the question whether a free falling charged particle does or not emit radiation), and -at the quantum level- yields a remarkable mass spectrum for leptons. After having briefly reviewed Caldirola`s approach, the first aim of the authors is to work out, discuss, and compare one another the mew representations of Quantum Mechanics (QM) resulting from it, in the Schroedinger, Heisenberg and density-operator (Liouville-von Neumann) pictures, respectively.The authors also obtain the (retarded) finite-difference Schroedinger equation within the Feynman path integral approach, and study some of its relevant solutions. They, then, derive the time-evolution operators of this discrete theory, and use them to get the finite-difference Heisenberg equations. At last, the density matrix formalism is applied to the solution of the measurement problem in QM, with very interesting results, so as a natural explication of `decoherence`, which reveal the power of dicretized (in particular, retarded) QM.

  7. Introduction of a quantum of time (`chronon`) and its consequences for quantum mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Farias, R H.A. [Lab. Nacional de Luz Sincrotron, Campinas, SP (Brazil); Recami, E [Bergamo Univ. (Italy). Fac. di Ingegneria; [INFN, Milan (Italy); [Campinas, State University, SP (Brazil). DMO-FEEC, CCS

    1999-12-31

    The authors discuss the consequences of the introduction of a quantum of time {tau}{sub 0} in the formalism of non-relativistic quantum mechanics, by referring themselves in particular to the theory of the chronon as proposed by P. Caldirola. Such an interesting `finite difference` theory, forwards -at the classical level- a solution for the motion of a particle endowed with a non-negligible charge in an external electromagnetic field, overcoming all the known difficulties met by Abraham-Lorentz`s and Dirac`s approaches (and even allowing a clear answer to the question whether a free falling charged particle does or not emit radiation), and -at the quantum level- yields a remarkable mass spectrum for leptons. After having briefly reviewed Caldirola`s approach, the first aim of the authors is to work out, discuss, and compare one another the mew representations of Quantum Mechanics (QM) resulting from it, in the Schroedinger, Heisenberg and density-operator (Liouville-von Neumann) pictures, respectively.The authors also obtain the (retarded) finite-difference Schroedinger equation within the Feynman path integral approach, and study some of its relevant solutions. They, then, derive the time-evolution operators of this discrete theory, and use them to get the finite-difference Heisenberg equations. At last, the density matrix formalism is applied to the solution of the measurement problem in QM, with very interesting results, so as a natural explication of `decoherence`, which reveal the power of dicretized (in particular, retarded) QM.

  8. Microbubble responses to a similar mechanical index with different real-time perfusion imaging techniques.

    Science.gov (United States)

    Porter, Thomas R; Oberdorfer, Joseph; Rafter, Patrick; Lof, John; Xie, Feng

    2003-08-01

    The purpose of this study was to determine differences in contrast enhancement and microbubble destruction rates with current commercially available low-mechanical index (MI) real-time perfusion imaging modalities. A tissue-mimicking phantom was developed that had vessels at 3 cm (near field) and 9 cm (far field) from a real-time transducer. Perfluorocarbon-exposed sonicated dextrose albumin microbubbles (PESDA) were injected proximal to a mixing chamber, and then passed through these vessels while the region was insonified with either pulses of alternating polarity with pulse inversion Doppler (PID) or pulses of alternating amplitude by power modulation (PM) at MIs of 0.1, 0.2 and 0.3. Effluent microbubble concentration, contrast intensity and the slope of digital contrast intensity vs. time were measured. Our results demonstrated that microbubble destruction already occurs with PID at an MI of 0.1. Contrast intensity seen with PID was less than with PM. Therefore, differences in contrast enhancement and microbubble destruction rates occur at a similar MI setting when using different real-time pulse sequence schemes.

  9. Mechanism by which BMI influences leisure-time physical activity behavior.

    Science.gov (United States)

    Godin, Gaston; Bélanger-Gravel, Ariane; Nolin, Bertrand

    2008-06-01

    The objective of this prospective study was to clarify the mechanism by which BMI influences leisure-time physical activity. This was achieved in accordance with the assumptions underlying the Theory of Planned Behavior (TPB), considered as one of the most useful theories to predict behavior adoption. At baseline, a sample of 1,530 respondents completed a short questionnaire to measure intention and perceived behavioral control (PBC), the two proximal determinants of behavior of TPB. Past behavior, sociodemographic variables, and weight and height were also assessed. The dependent variable, leisure-time physical activity was assessed 3 months later. Hierarchical multiple regression analyses revealed that BMI is a direct predictor of future leisure-time physical activity, not mediated by the variables of TPB. Additional hierarchical analyses indicated that BMI was not a moderator of the intention-behavior and PBC-behavior relationships. The results of this study suggest that high BMI is a significant negative determinant of leisure-time physical activity. This observation reinforces the importance of preventing weight gain as a health promotion strategy for avoiding a sedentary lifestyle.

  10. Beginning SharePoint 2010 Administration Windows SharePoint Foundation 2010 and Microsoft SharePoint Server 2010

    CERN Document Server

    Husman, Göran

    2010-01-01

    Complete coverage on the latest advances in SharePoint 2010 administration. SharePoint 2010 comprises an abundance of new features, and this book shows you how to take advantage of all SharePoint 2010's many improvements. Written by a four-time SharePoint MVP, Beginning SharePoint 2010 Administration begins with a comparison of SharePoint 2010 compared to the previous version and then examines the differences between WSS 4.0 and MSS 2010. Packed with step-by-step instructions, tips and tricks, and real-world examples, this book dives into the basics of how to install, manage, and administrate

  11. Guarantee of remaining life time. Integrity of mechanical components and control of ageing phenomena

    International Nuclear Information System (INIS)

    Schuler, X.; Herter, K.H.; Koenig, G.

    2012-01-01

    The life time of safety relevant systems, structures and components (SSC) of Nuclear Power Plants (NPP) is determined by two main principles. First of all the required quality has to be produced during the design and fabrication process. This means that quality has to be produced and can't be improved by excessive inspections (Basis Safety - quality through production principle). The second one is assigned to the initial quality which has to be maintained during operation. This concerns safe operation during the total life time (life time management), safety against ageing phenomena (AM - ageing management) as well as proof of integrity (e.g. break preclusion or avoidance of fracture for SSC with high safety relevance). Initiated by the Fukushima Dai-ichi event in Japan in spring 2011 for German NPP's Long Term Operation (LTO) is out of question. In June 2011 legislation took decision to phase-out from nuclear by 2022. As a fact safe operation shall be guaranteed for the remaining life time. Within this technical framework the ageing management is a key element. Depending on the safety-relevance of the SSC under observation including preventive maintenance various tasks are required in particular to clarify the mechanisms which contribute systemspecifically to the damage of the components and systems and to define their controlling parameters which have to be monitored and checked. Appropriate continuous or discontinuous measures are to be considered in this connection. The approach to ensure a high standard of quality in operation for the remaining life time and the management of the technical and organizational aspects are demonstrated and explained. The basis for ageing management to be applied to NNPs is included in Nuclear Safety Standard 1403 which describes the ageing management procedures. For SSC with high safety relevance a verification analysis for rupture preclusion (proof of integrity, integrity concept) shall be performed (Nuclear Safety Standard 3206

  12. Introduction of a quantum of time (''chronon'') and its consequences for quantum mechanics

    International Nuclear Information System (INIS)

    Farias, R.H.A.; Recami, E.

    1998-07-01

    We discuss the consequences of the introduction of a quantum of time τ 0 in the formalism of non-relativistic quantum mechanics, by referring ourselves, in particular, to the theory of the chronon as proposed by P. Caldirola. Such an interesting ''finite difference'' theory, forwards - at the classical level - a solution for the motion of a particle endowed with a non-negligible charge in an external electromagnetic field, overcoming all the known difficulties met by Abraham-Lorentz's and Dirac's approaches (and even allowing a clear answer to the question whether a free falling charged particle does or does not emit radiation), and - at the quantum level - yields a remarkable mass spectrum for leptons. After having briefly reviewed Caldirola's approach, our first aim is to work out, discuss, and compare to one another the new representations of Quantum Mechanics (QM) resulting from it, in the Schroedinger, Heisenberg and density-operator (Liouville-von Neumann) pictures, respectively. Moreover, for each representation, three (retarded, symmetric and advanced) formulations are possible, which refer either to times t and t-τ 0 , or to times t-τ 0 /2 and t+τ 0 /2, or to times t and t+τ 0 , respectively. It is interesting to notice that, when the chronon tends to zero, the ordinary QM is obtained as the limiting case of the ''symmetric'' formulation only; while the ''retarded'' one does naturally appear to describe QM with friction, i.e., to describe dissipative quantum systems (like a particle moving in an absorbing medium). In this sense, discretized QM is much richer than the ordinary one. We also obtain the (retarded) finite-difference Schroedinger equation within the Feynman path integral approach, and study some of its relevant solutions. We then derive the time-evolution operators of this discrete theory, and use them to get the finite-difference Heisenberg equations. When discussing the mutual compatibility of the various pictures listed above, we find

  13. The time-local view of nonequilibrium statistical mechanics. I. Linear theory of transport and relaxation

    Science.gov (United States)

    der, R.

    1987-01-01

    The various approaches to nonequilibrium statistical mechanics may be subdivided into convolution and convolutionless (time-local) ones. While the former, put forward by Zwanzig, Mori, and others, are used most commonly, the latter are less well developed, but have proven very useful in recent applications. The aim of the present series of papers is to develop the time-local picture (TLP) of nonequilibrium statistical mechanics on a new footing and to consider its physical implications for topics such as the formulation of irreversible thermodynamics. The most natural approach to TLP is seen to derive from the Fourier-Laplace transformwidetilde{C}(z)) of pertinent time correlation functions, which on the physical sheet typically displays an essential singularity at z=∞ and a number of macroscopic and microscopic poles in the lower half-plane corresponding to long- and short-lived modes, respectively, the former giving rise to the autonomous macrodynamics, whereas the latter are interpreted as doorway modes mediating the transfer of information from relevant to irrelevant channels. Possible implications of this doorway mode concept for socalled extended irreversible thermodynamics are briefly discussed. The pole structure is used for deriving new kinds of generalized Green-Kubo relations expressing macroscopic quantities, transport coefficients, e.g., by contour integrals over current-current correlation functions obeying Hamiltonian dynamics, the contour integration replacing projection. The conventional Green-Kubo relations valid for conserved quantities only are rederived for illustration. Moreover,widetilde{C}(z) may be expressed by a Laurent series expansion in positive and negative powers of z, from which a rigorous, general, and straightforward method is developed for extracting all macroscopic quantities from so-called secularly divergent expansions ofwidetilde{C}(z) as obtained from the application of conventional many-body techniques to the calculation

  14. Temporal predictive mechanisms modulate motor reaction time during initiation and inhibition of speech and hand movement.

    Science.gov (United States)

    Johari, Karim; Behroozmand, Roozbeh

    2017-08-01

    Skilled movement is mediated by motor commands executed with extremely fine temporal precision. The question of how the brain incorporates temporal information to perform motor actions has remained unanswered. This study investigated the effect of stimulus temporal predictability on response timing of speech and hand movement. Subjects performed a randomized vowel vocalization or button press task in two counterbalanced blocks in response to temporally-predictable and unpredictable visual cues. Results indicated that speech and hand reaction time was decreased for predictable compared with unpredictable stimuli. This finding suggests that a temporal predictive code is established to capture temporal dynamics of sensory cues in order to produce faster movements in responses to predictable stimuli. In addition, results revealed a main effect of modality, indicating faster hand movement compared with speech. We suggest that this effect is accounted for by the inherent complexity of speech production compared with hand movement. Lastly, we found that movement inhibition was faster than initiation for both hand and speech, suggesting that movement initiation requires a longer processing time to coordinate activities across multiple regions in the brain. These findings provide new insights into the mechanisms of temporal information processing during initiation and inhibition of speech and hand movement. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Gravity, two times, tractors, Weyl invariance, and six-dimensional quantum mechanics

    International Nuclear Information System (INIS)

    Bonezzi, R.; Latini, E.; Waldron, A.

    2010-01-01

    Fefferman and Graham showed some time ago that four-dimensional conformal geometries could be analyzed in terms of six-dimensional, ambient, Riemannian geometries admitting a closed homothety. Recently, it was shown how conformal geometry provides a description of physics manifestly invariant under local choices of unit systems. Strikingly, Einstein's equations are then equivalent to the existence of a parallel scale tractor (a six-component vector subject to a certain first order covariant constancy condition at every point in four-dimensional spacetime). These results suggest a six-dimensional description of four-dimensional physics, a viewpoint promulgated by the 2 times physics program of Bars. The Fefferman-Graham construction relies on a triplet of operators corresponding, respectively, to a curved six-dimensional light cone, the dilation generator and the Laplacian. These form an sp(2) algebra which Bars employs as a first class algebra of constraints in a six-dimensional gauge theory. In this article four-dimensional gravity is recast in terms of six-dimensional quantum mechanics by melding the 2 times and tractor approaches. This parent formulation of gravity is built from an infinite set of six-dimensional fields. Successively integrating out these fields yields various novel descriptions of gravity including a new four-dimensional one built from a scalar doublet, a tractor-vector multiplet and a conformal class of metrics.

  16. Reliable file sharing in distributed operating system using web RTC

    Science.gov (United States)

    Dukiya, Rajesh

    2017-12-01

    Since, the evolution of distributed operating system, distributed file system is come out to be important part in operating system. P2P is a reliable way in Distributed Operating System for file sharing. It was introduced in 1999, later it became a high research interest topic. Peer to Peer network is a type of network, where peers share network workload and other load related tasks. A P2P network can be a period of time connection, where a bunch of computers connected by a USB (Universal Serial Bus) port to transfer or enable disk sharing i.e. file sharing. Currently P2P requires special network that should be designed in P2P way. Nowadays, there is a big influence of browsers in our life. In this project we are going to study of file sharing mechanism in distributed operating system in web browsers, where we will try to find performance bottlenecks which our research will going to be an improvement in file sharing by performance and scalability in distributed file systems. Additionally, we will discuss the scope of Web Torrent file sharing and free-riding in peer to peer networks.

  17. One-way shared memory

    DEFF Research Database (Denmark)

    Schoeberl, Martin

    2018-01-01

    Standard multicore processors use the shared main memory via the on-chip caches for communication between cores. However, this form of communication has two limitations: (1) it is hardly time-predictable and therefore not a good solution for real-time systems and (2) this single shared memory...... is a bottleneck in the system. This paper presents a communication architecture for time-predictable multicore systems where core-local memories are distributed on the chip. A network-on-chip constantly copies data from a sender core-local memory to a receiver core-local memory. As this copying is performed...... in one direction we call this architecture a one-way shared memory. With the use of time-division multiplexing for the memory accesses and the network-on-chip routers we achieve a time-predictable solution where the communication latency and bandwidth can be bounded. An example architecture for a 3...

  18. Time of elevation of head of bed for patients receiving mechanical ventilation and its related factors.

    Science.gov (United States)

    Martí-Hereu, L; Arreciado Marañón, A

    The semirecumbent position is a widespread recommendation for the prevention of pneumonia associated with mechanical ventilation. To identify the time of elevation of head of bed for patients under mechanical ventilation and the factors related to such elevation in an intensive care unit. An observational, descriptive cross-sectional study. Conducted in an intensive care unit of a tertiary hospital from April to June 2015. The studied population were mechanically ventilated patients. Daily hours in which patients remained with the head of the bed elevated (≥30°), socio-demographic data and clinical variables were recorded. 261 head elevation measurements were collected. The average daily hours that patients remained at ≥30° was 16h28' (SD ±5h38'), equivalent to 68.6% (SD ±23.5%) of the day. Factors related to elevations ≥30° for longer were: enteral nutrition, levels of deep sedation, cardiac and neurocritical diagnostics. Factors that hindered the position were: sedation levels for agitation and abdominal pathologies. Sex, age and ventilation mode did not show a significant relationship with bed head elevation. Although raising the head of the bed is an easy to perform, economical and measurable preventive measure, its compliance is low due to specific factors specific related o the patient's clinical condition. Using innovations such as continuous measurement of the head position helps to evaluate clinical practice and allows to carry out improvement actions whose impact is beneficial to the patient. Copyright © 2017 Sociedad Española de Enfermería Intensiva y Unidades Coronarias (SEEIUC). Publicado por Elsevier España, S.L.U. All rights reserved.

  19. Quality Saving Mechanisms of Mitochondria during Aging in a Fully Time-Dependent Computational Biophysical Model.

    Directory of Open Access Journals (Sweden)

    Daniel Mellem

    Full Text Available Mitochondria are essential for the energy production of eukaryotic cells. During aging mitochondria run through various processes which change their quality in terms of activity, health and metabolic supply. In recent years, many of these processes such as fission and fusion of mitochondria, mitophagy, mitochondrial biogenesis and energy consumption have been subject of research. Based on numerous experimental insights, it was possible to qualify mitochondrial behaviour in computational simulations. Here, we present a new biophysical model based on the approach of Figge et al. in 2012. We introduce exponential decay and growth laws for each mitochondrial process to derive its time-dependent probability during the aging of cells. All mitochondrial processes of the original model are mathematically and biophysically redefined and additional processes are implemented: Mitochondrial fission and fusion is separated into a metabolic outer-membrane part and a protein-related inner-membrane part, a quality-dependent threshold for mitophagy and mitochondrial biogenesis is introduced and processes for activity-dependent internal oxidative stress as well as mitochondrial repair mechanisms are newly included. Our findings reveal a decrease of mitochondrial quality and a fragmentation of the mitochondrial network during aging. Additionally, the model discloses a quality increasing mechanism due to the interplay of the mitophagy and biogenesis cycle and the fission and fusion cycle of mitochondria. It is revealed that decreased mitochondrial repair can be a quality saving process in aged cells. Furthermore, the model finds strategies to sustain the quality of the mitochondrial network in cells with high production rates of reactive oxygen species due to large energy demands. Hence, the model adds new insights to biophysical mechanisms of mitochondrial aging and provides novel understandings of the interdependency of mitochondrial processes.

  20. Sharing Keynote Slideshows

    CERN Document Server

    Clark, Josh

    2010-01-01

    Slideshows have come a long way since overhead projectors were your only option. You can show share your ideas with the world via email, DVD, PDF, YouTube, iPhone, or kiosk. Once your show is polished to perfection, this thorough, accessible guide shows you how to export and deliver it all possible ways-even as a PowerPoint file, QuickTime movie, or web site. As a bonus, you'll find advice on setting up your equipment and delivering an effective presentation.

  1. Effect Of Milling Time On Microstructure Of AA6061 Composites Fabricated Via Mechanical Alloying

    Directory of Open Access Journals (Sweden)

    Tomiczek B.

    2015-06-01

    Full Text Available The aim of this work is to determine the effect of manufacturing conditions, especially milling time, on the microstructure and crystallite size of a newly developed nanostructural composite material with the aluminium alloy matrix reinforced with halloysite nanotubes. Halloysite, being a clayey mineral of volcanic origin, is characterized by high porosity and large specific surface area. Thus it can be used as an alternative reinforcement in metal matrix composite materials. In order to obtain this goal, composite powders with fine microstructures were fabricated using high-energy mechanical alloying, cold compacting and hot extrusion techniques. The obtained composite powders of aluminium alloy reinforced with 5, 10 and 15 wt% of halloysite nanotubes were characterized with SEM, TEM and XRD analysis. It has been proven that the use of mechanical alloying leads to a high degree of deformation, which, coupled with a decreased grain size below 100 nm and the dispersion of the refined reinforcing particles–reinforces the material very well.

  2. Real-time transient stabilization and voltage regulation of power generators with unknown mechanical power input

    International Nuclear Information System (INIS)

    Kenne, Godpromesse; Goma, Raphael; Nkwawo, Homere; Lamnabhi-Lagarrigue, Francoise; Arzande, Amir; Vannier, Jean Claude

    2010-01-01

    A nonlinear adaptive excitation controller is proposed to enhance the transient stability and voltage regulation of synchronous generators with unknown power angle and mechanical power input. The proposed method is based on a standard third-order model of a synchronous generator which requires only information about the physical available measurements of relative angular speed, active electric power, infinite bus and generator terminal voltages. The operating conditions are computed online using the above physical available measurements, the terminal voltage reference value and the estimate of the mechanical power input. The proposed design is therefore capable of providing satisfactory voltage in the presence of unknown variations of the power system operating conditions. Using the concept of sliding mode equivalent control techniques, a robust decentralized adaptive controller which insures the exponential convergence of the outputs to the desired ones, is obtained. Real-time experimental results are reported, comparing the performance of the proposed adaptive nonlinear control scheme to one of the conventional AVR/PSS controller. The high simplicity of the overall adaptive control scheme and its robustness with respect to line impedance variation including critical unbalanced operating condition and temporary turbine fault, constitute the main positive features of the proposed approach.

  3. Rhythm in joint action: psychological and neurophysiological mechanisms for real-time interpersonal coordination

    Science.gov (United States)

    Keller, Peter E.; Novembre, Giacomo; Hove, Michael J.

    2014-01-01

    Human interaction often requires simultaneous precision and flexibility in the coordination of rhythmic behaviour between individuals engaged in joint activity, for example, playing a musical duet or dancing with a partner. This review article addresses the psychological processes and brain mechanisms that enable such rhythmic interpersonal coordination. First, an overview is given of research on the cognitive-motor processes that enable individuals to represent joint action goals and to anticipate, attend and adapt to other's actions in real time. Second, the neurophysiological mechanisms that underpin rhythmic interpersonal coordination are sought in studies of sensorimotor and cognitive processes that play a role in the representation and integration of self- and other-related actions within and between individuals' brains. Finally, relationships between social–psychological factors and rhythmic interpersonal coordination are considered from two perspectives, one concerning how social-cognitive tendencies (e.g. empathy) affect coordination, and the other concerning how coordination affects interpersonal affiliation, trust and prosocial behaviour. Our review highlights musical ensemble performance as an ecologically valid yet readily controlled domain for investigating rhythm in joint action. PMID:25385772

  4. Real-time transient stabilization and voltage regulation of power generators with unknown mechanical power input

    Energy Technology Data Exchange (ETDEWEB)

    Kenne, Godpromesse, E-mail: gokenne@yahoo.co [Laboratoire d' Automatique et d' Informatique Appliquee (LAIA), Departement de Genie Electrique, Universite de Dschang, B.P. 134 Bandjoun (Cameroon); Goma, Raphael, E-mail: raphael.goma@lss.supelec.f [Laboratoire des Signaux et Systemes (L2S), CNRS-SUPELEC, Universite Paris XI, 3 Rue Joliot Curie, 91192 Gif-sur-Yvette (France); Nkwawo, Homere, E-mail: homere.nkwawo@iutv.univ-paris13.f [Departement GEII, Universite Paris XIII, 99 Avenue Jean Baptiste Clement, 93430 Villetaneuse (France); Lamnabhi-Lagarrigue, Francoise, E-mail: lamnabhi@lss.supelec.f [Laboratoire des Signaux et Systemes (L2S), CNRS-SUPELEC, Universite Paris XI, 3 Rue Joliot Curie, 91192 Gif-sur-Yvette (France); Arzande, Amir, E-mail: Amir.arzande@supelec.f [Departement Energie, Ecole Superieure d' Electricite-SUPELEC, 3 Rue Joliot Curie, 91192 Gif-sur-Yvette (France); Vannier, Jean Claude, E-mail: Jean-claude.vannier@supelec.f [Departement Energie, Ecole Superieure d' Electricite-SUPELEC, 3 Rue Joliot Curie, 91192 Gif-sur-Yvette (France)

    2010-01-15

    A nonlinear adaptive excitation controller is proposed to enhance the transient stability and voltage regulation of synchronous generators with unknown power angle and mechanical power input. The proposed method is based on a standard third-order model of a synchronous generator which requires only information about the physical available measurements of relative angular speed, active electric power, infinite bus and generator terminal voltages. The operating conditions are computed online using the above physical available measurements, the terminal voltage reference value and the estimate of the mechanical power input. The proposed design is therefore capable of providing satisfactory voltage in the presence of unknown variations of the power system operating conditions. Using the concept of sliding mode equivalent control techniques, a robust decentralized adaptive controller which insures the exponential convergence of the outputs to the desired ones, is obtained. Real-time experimental results are reported, comparing the performance of the proposed adaptive nonlinear control scheme to one of the conventional AVR/PSS controller. The high simplicity of the overall adaptive control scheme and its robustness with respect to line impedance variation including critical unbalanced operating condition and temporary turbine fault, constitute the main positive features of the proposed approach.

  5. Effect of austempering temperature and time on mechanical properties of SAE 9260 steel

    Science.gov (United States)

    Dalwatkar, Ranjit; Prabhu, N.; Singh, R. K. P.

    2018-04-01

    This work describes the effect of austempering heat treatment on microstrcuture and mechanical properties of SAE 9260 steel. Steel samples, austenitized at 900 °C for one hour, were isothermally heat treated in the temperature range 300,325 and 350 °C for different times. Microstructural characterization was carried out using optical and scanning electron microscopes. The microstructure of the austempered samples consisted of bainitic ferrite and retained austenite. The volume fraction of retained austenite was determined using X-ray diffraction. Isothermal heat treatment at 350 °C for 20 min, resulted in a retained austenite content of around 38% in the microstructure. Increase in isothermal transformation temperature led to an increase in the fraction of retained austenite. Also, good combination of strength and ductility was obtained in the samples with increased amounts of retained austenite.

  6. Short-time, high temperature mechanical testing of electrically conductive materials

    International Nuclear Information System (INIS)

    Marion, R.H.; Karnes, C.H.

    1975-10-01

    Design and performance details are given for a facility which was developed to obtain the mechanical properties of materials under high heating rate or transient temperature conditions and medium strain rates. The system is shown to be applicable to materials possessing electrical resistivities ranging from that of aluminum to that of graphite without taxing the heating capability. Heating rates as high as 2000 0 K/s in graphite are attained under controlled conditions. Methods of measuring temperature and the effects of expected temperature distributions are discussed. A method for measuring strain valid for transient temperature conditions to 3000 0 K is described. Results are presented for the stress-strain behavior of 316 stainless steel and ATJ(S) graphite obtained for heating times of a few seconds. (auth)

  7. Online Identification of a Mechanical System in the Frequency Domain with Short-Time DFT

    Directory of Open Access Journals (Sweden)

    Niko Nevaranta

    2015-07-01

    Full Text Available A proper system identification method is of great importance in the process of acquiring an analytical model that adequately represents the characteristics of the monitored system. While the use of different time-domain online identification techniques has been widely recognized as a powerful approach for system diagnostics, the frequency domain identification techniques have primarily been considered for offline commissioning purposes. This paper addresses issues in the online frequency domain identification of a flexible two-mass mechanical system with varying dynamics, and a particular attention is paid to detect the changes in the system dynamics. An online identification method is presented that is based on a recursive Kalman filter configured to perform like a discrete Fourier transform (DFT at a selected set of frequencies. The experimental online identification results are compared with the corresponding values obtained from the offline-identified frequency responses. The results show an acceptable agreement and demonstrate the feasibility of the proposed identification method.

  8. Resolving nanoparticle growth mechanisms from size- and time-dependent growth rate analysis

    Science.gov (United States)

    Pichelstorfer, Lukas; Stolzenburg, Dominik; Ortega, John; Karl, Thomas; Kokkola, Harri; Laakso, Anton; Lehtinen, Kari E. J.; Smith, James N.; McMurry, Peter H.; Winkler, Paul M.

    2018-01-01

    Atmospheric new particle formation occurs frequently in the global atmosphere and may play a crucial role in climate by affecting cloud properties. The relevance of newly formed nanoparticles depends largely on the dynamics governing their initial formation and growth to sizes where they become important for cloud microphysics. One key to the proper understanding of nanoparticle effects on climate is therefore hidden in the growth mechanisms. In this study we have developed and successfully tested two independent methods based on the aerosol general dynamics equation, allowing detailed retrieval of time- and size-dependent nanoparticle growth rates. Both methods were used to analyze particle formation from two different biogenic precursor vapors in controlled chamber experiments. Our results suggest that growth rates below 10 nm show much more variation than is currently thought and pin down the decisive size range of growth at around 5 nm where in-depth studies of physical and chemical particle properties are needed.

  9. Development of diverse methods for drop time measurement of PFBR shut down mechanisms

    International Nuclear Information System (INIS)

    Prakash, V.; Nashine, B.K.; Padmakumar, G.; Vijayashree, R.; Sharma, Prashant; Patri, Sudheer; Chandramouli, S.; Rajan, K.K.

    2015-01-01

    Prototype Fast Breeder Reactor (PFBR) is equipped with two shutdown systems namely, Control and Safety Rod Drive Mechanism (CSRDM) and Diverse Safety Rod Drive Mechanism (DSRDM). DSRDM is used for the safe shut down of the reactor. During a SCRAM, DSR is released from its electromagnet and falls into the reactor core under gravity. It is a safety requirement to measure the fall time of DSR during each SCRAM. As no sensor can be attached to the moving part of DSR, non-contact type measurement techniques namely acoustic and eddy current methods are envisaged for the measurement of DSR fall time in PFBR. Acoustic technique uses accelerometer mounted on upper part of DSRDM for the detection of acoustic events during the movement of DSR in the DSR subassembly. Measurements were carried out in various water/sodium facilities and an On-line measurement system for PFBR has been developed. The developed system was tested for its performance and results were compared with ultrasonic method to establish its measurement sensitivity. Eddy current position sensor uses the property of change in inductance due to the entry of DSR piston into the DSR dashpot region. DSR piston, which is made up of modified 9Cr-1Mo steel, replaces the liquid sodium in the dashpot, which results in a change in inductance in the sensor coil embedded in DSR subassembly sheath near the entry of dashpot. A sensor with two pick-up coils was successfully developed and tested in sodium at various temperatures for various test conditions. The developed eddy current system was installed in prototype DSRDM, tested for its performance and the results are compared with acoustic technique. This paper discusses the details of the developmental activities of both the techniques and their experimental verification using prototype DSRDM. (author)

  10. Qualitative Data Sharing Practices in Social Sciences

    Science.gov (United States)

    Jeng, Wei

    2017-01-01

    Social scientists have been sharing data for a long time. Sharing qualitative data, however, has not become a common practice, despite the context of e-Research, information growth, and funding agencies' mandates on research data archiving and sharing. Since most systematic and comprehensive studies are based on quantitative data practices, little…

  11. A unified model of time perception accounts for duration-based and beat-based timing mechanisms

    Directory of Open Access Journals (Sweden)

    Sundeep eTeki

    2012-01-01

    Full Text Available Accurate timing is an integral aspect of sensory and motor processes such as the perception of speech and music and the execution of skilled movement. Neuropsychological studies of time perception in patient groups and functional neuroimaging studies of timing in normal participants suggest common neural substrates for perceptual and motor timing. A timing system is implicated in core regions of the motor network such as the cerebellum, inferior olive, basal ganglia, pre-supplementary and supplementary motor area, pre-motor cortex and higher regions such as the prefrontal cortex.In this article, we assess how distinct parts of the timing system subserve different aspects of perceptual timing. We previously established brain bases for absolute, duration-based timing and relative, beat-based timing in the olivocerebellar and striato-thalamo-cortical circuits respectively (Teki et al., 2011. However, neurophysiological and neuroanatomical studies provide a basis to suggest that timing functions of these circuits may not be independent.Here, we propose a unified model of time perception based on coordinated activity in the core striatal and olivocerebellar networks that are interconnected with each other and the cerebral cortex th

  12. Processing Mechanisms in Hearing-Impaired Listeners: Evidence from Reaction Times and Sentence Interpretation.

    Science.gov (United States)

    Carroll, Rebecca; Uslar, Verena; Brand, Thomas; Ruigendijk, Esther

    The authors aimed to determine whether hearing impairment affects sentence comprehension beyond phoneme or word recognition (i.e., on the sentence level), and to distinguish grammatically induced processing difficulties in structurally complex sentences from perceptual difficulties associated with listening to degraded speech. Effects of hearing impairment or speech in noise were expected to reflect hearer-specific speech recognition difficulties. Any additional processing time caused by the sustained perceptual challenges across the sentence may either be independent of or interact with top-down processing mechanisms associated with grammatical sentence structure. Forty-nine participants listened to canonical subject-initial or noncanonical object-initial sentences that were presented either in quiet or in noise. Twenty-four participants had mild-to-moderate hearing impairment and received hearing-loss-specific amplification. Twenty-five participants were age-matched peers with normal hearing status. Reaction times were measured on-line at syntactically critical processing points as well as two control points to capture differences in processing mechanisms. An off-line comprehension task served as an additional indicator of sentence (mis)interpretation, and enforced syntactic processing. The authors found general effects of hearing impairment and speech in noise that negatively affected perceptual processing, and an effect of word order, where complex grammar locally caused processing difficulties for the noncanonical sentence structure. Listeners with hearing impairment were hardly affected by noise at the beginning of the sentence, but were affected markedly toward the end of the sentence, indicating a sustained perceptual effect of speech recognition. Comprehension of sentences with noncanonical word order was negatively affected by degraded signals even after sentence presentation. Hearing impairment adds perceptual processing load during sentence processing

  13. Birth Order and Child Cognitive Outcomes: An Exploration of the Parental Time Mechanism

    Science.gov (United States)

    Monfardini, Chiara; See, Sarah Grace

    2016-01-01

    Higher birth order positions are associated with poorer outcomes due to smaller shares of resources received within the household. Using a sample of Panel Study of Income Dynamics-Child Development Supplement children, we investigate if the negative birth order effect we find in cognitive outcomes is due to unequal allocation of mother and father…

  14. Mapping the landscape of shared leadership

    DEFF Research Database (Denmark)

    Ulhøi, John Parm; Müller, Sabine

    2014-01-01

    As can be seen from the substantial increase in the volume and scope of leadership publications over the last ten to fifteen years, leadership is a construct with important social and relational properties. Shared leadership in particular has attracted considerable attention from organization......, and to develop synthesized framework of shared leadership. The paper closes with a brief discussion of avenues for future research and implications for managers....... and management scholars, although there has been surprisingly little focus on the key structuring processes and mechanisms that enable shared leadership. The aim of this paper is to rectify this by identifying the critical factors and mechanisms which enable shared leadership and its antecedents and outcomes...

  15. Time variations in the mechanical characteristics of local crustal segments according to seismic observations

    Science.gov (United States)

    Kocharyan, G. G.; Gamburtseva, N. G.; Sanina, I. A.; Danilova, T. V.; Nesterkina, M. A.; Gorbunova, E. M.; Ivanchenko, G. N.

    2011-04-01

    The results of the seismic observations made with two different experimental setups are presented. In the first case, the signals produced by underground nuclear explosions at the Semipalatinsk Test Site were measured on a linear profile, which allowed one to definitely outline the areas where the mechanical properties of rocks experienced considerable time variations. In the second case, the waves excited by the open-pit mine blasts recorded at a small-aperture seismic array at the Mikhnevo Geophysical Station (Institute of Geosphere Dynamics, Russian Academy of Sciences) on the East European Platform favored the estimation of variations in the integral characteristics of the seismic path. Measurements in aseismic regions characterized by diverse geological structure and different tectonic conditions revealed similar effects of the strong dependency of seismic parameters on the time of explosions. Here, the variations experienced by the maximum amplitudes of oscillations and irrelevant to seasonal changes or local conditions reached a factor of two. The generic periods of these variations including the distinct annual rhythm are probably the fragments of a lower-frequency process. The obtained results suggest that these variations are due to changes in the stressstrain state of active fault zones, which, in turn, can be associated with the macroscale motion of large blocks triggered by tidal strains, tectonic forces and, possibly, variations in the rate of the Earth's rotation.

  16. The time-course of feature interference in agreement comprehension: Multiple mechanisms and asymmetrical attraction.

    Science.gov (United States)

    Tanner, Darren; Nicol, Janet; Brehm, Laurel

    2014-10-01

    Attraction interference in language comprehension and production may be as a result of common or different processes. In the present paper, we investigate attraction interference during language comprehension, focusing on the contexts in which interference arises and the time-course of these effects. Using evidence from event-related brain potentials (ERPs) and sentence judgment times, we show that agreement attraction in comprehension is best explained as morphosyntactic interference during memory retrieval. This stands in contrast to attraction as a message-level process involving the representation of the subject NP's number features, which is a strong contributor to attraction in production. We thus argue that the cognitive antecedents of agreement attraction in comprehension are non-identical with those of attraction in production, and moreover, that attraction in comprehension is primarily a consequence of similarity-based interference in cue-based memory retrieval processes. We suggest that mechanisms responsible for attraction during language comprehension are a subset of those involved in language production.

  17. The electro-mechanical integration of the NA62 GigaTracker time tagging pixel detector

    CERN Document Server

    Morel, M; Aglieri Rinella, G; Carassiti, V; Ceccucci, A; Daguin, J; Fiorini, M; Jarron, P; Kaplon, J; Mapelli, A; Marchetto, F; Noy, M; Nuessle, G; Perktold, L; Petagna, P; Riedler, P

    2010-01-01

    The NA62 GigaTracker is a low mass time tagging hybrid pixel detector operating in a beam with a particle rate of 750 MHz. It consists of three stations with a sensor size of 60 × 27mm2 containing 18000 pixels, each 300 × 300μm2. The active area is connected to a matrix of 2 × 5 pixel ASICs, which time tag the arrival of the particles with a binning of 100 ps. The detector operates in vacuum at -20 to 0°C and the material budget per station must be below 0.5% X0. Due to the high radiation environment of 2 × 1014 1 MeV neutron equivalent cm−2/yr−1 it is planned to exchange the detector modules regularly. The low material budget, cooling requirements and the request for easy module access has driven the electro-mechanical integration of the GigaTracker, which is presented in this paper

  18. The strength and timing of the mitochondrial bottleneck in salmon suggests a conserved mechanism in vertebrates.

    Directory of Open Access Journals (Sweden)

    Jonci N Wolff

    Full Text Available In most species mitochondrial DNA (mtDNA is inherited maternally in an apparently clonal fashion, although how this is achieved remains uncertain. Population genetic studies show not only that individuals can harbor more than one type of mtDNA (heteroplasmy but that heteroplasmy is common and widespread across a diversity of taxa. Females harboring a mixture of mtDNAs may transmit varying proportions of each mtDNA type (haplotype to their offspring. However, mtDNA variants are also observed to segregate rapidly between generations despite the high mtDNA copy number in the oocyte, which suggests a genetic bottleneck acts during mtDNA transmission. Understanding the size and timing of this bottleneck is important for interpreting population genetic relationships and for predicting the inheritance of mtDNA based disease, but despite its importance the underlying mechanisms remain unclear. Empirical studies, restricted to mice, have shown that the mtDNA bottleneck could act either at embryogenesis, oogenesis or both. To investigate whether the size and timing of the mitochondrial bottleneck is conserved between distant vertebrates, we measured the genetic variance in mtDNA heteroplasmy at three developmental stages (female, ova and fry in chinook salmon and applied a new mathematical model to estimate the number of segregating units (N(e of the mitochondrial bottleneck between each stage. Using these data we estimate values for mtDNA Ne of 88.3 for oogenesis, and 80.3 for embryogenesis. Our results confirm the presence of a mitochondrial bottleneck in fish, and show that segregation of mtDNA variation is effectively complete by the end of oogenesis. Considering the extensive differences in reproductive physiology between fish and mammals, our results suggest the mechanism underlying the mtDNA bottleneck is conserved in these distant vertebrates both in terms of it magnitude and timing. This finding may lead to improvements in our understanding of

  19. Natural time analysis and Tsallis non-additive entropy statistical mechanics.

    Science.gov (United States)

    Sarlis, N. V.; Skordas, E. S.; Varotsos, P.

    2016-12-01

    Upon analyzing the seismic data in natural time and employing a sliding natural time window comprising a number of events that would occur in a few months, it has been recently uncovered[1] that a precursory Seismic Electric Signals activity[2] initiates almost simultaneously with the appearance of a minimum in the fluctuations of the order parameter of seismicity [3]. Such minima have been ascertained [4] during periods of the magnitude time series exhibiting long range correlations [5] a few months before all earthquakes of magnitude 7.6 or larger that occurred in the entire Japanese area from 1 January 1984 to 11 March 2011 (the day of the M9 Tohoku-Oki earthquake). Before and after these minima, characteristic changes of the temporal correlations between earthquake magnitudes are observed which cannot be captured by Tsallis non-additive entropy statistical mechanics in the frame of which it has been suggested that kappa distributions arise [6]. Here, we extend the study concerning the existence of such minima in a large area that includes Aegean Sea and its surrounding area which exhibits in general seismo-tectonics [7] different than that of the entire Japanese area. References P. A. Varotsos et al., Tectonophysics, 589 (2013) 116. P. Varotsos and M. Lazaridou, Tectonophysics 188 (1991) 321. P.A. Varotsos et al., Phys Rev E 72 (2005) 041103. N. V. Sarlis et al., Proc Natl Acad Sci USA 110 (2013) 13734. P. A. Varotsos, N. V. Sarlis, and E. S. Skordas, J Geophys Res Space Physics 119 (2014), 9192, doi: 10.1002/2014JA0205800. G. Livadiotis, and D. J. McComas, J Geophys Res 114 (2009) A11105, doi:10.1029/2009JA014352. S. Uyeda et al., Tectonophysics, 304 (1999) 41.

  20. Neuromuscular mechanisms and neural strategies in the control of time-varying muscle contractions.

    Science.gov (United States)

    Erimaki, Sophia; Agapaki, Orsalia M; Christakos, Constantinos N

    2013-09-01

    The organization of the neural input to motoneurons that underlies time-varying muscle force is assumed to depend on muscle transfer characteristics and neural strategies or control modes utilizing sensory signals. We jointly addressed these interlinked, but previously studied individually and partially, issues for sinusoidal (range 0.5-5.0 Hz) force-tracking contractions of a human finger muscle. Using spectral and correlation analyses of target signal, force signal, and motor unit (MU) discharges, we studied 1) patterns of such discharges, allowing inferences on the motoneuronal input; 2) transformation of MU population activity (EMG) into quasi-sinusoidal force; and 3) relation of force oscillation to target, carrying information on the input's organization. A broad view of force control mechanisms and strategies emerged. Specifically, synchronized MU and EMG modulations, reflecting a frequency-modulated motoneuronal input, accompanied the force variations. Gain and delay drops between EMG modulation and force oscillation, critical for the appropriate organization of this input, occurred with increasing target frequency. According to our analyses, gain compensation was achieved primarily through rhythmical activation/deactivation of higher-threshold MUs and secondarily through the adaptation of the input's strength expected during tracking tasks. However, the input's timing was not adapted to delay behaviors and seemed to depend on the control modes employed. Thus, for low-frequency targets, the force oscillation was highly coherent with, but led, a target, this timing error being compatible with predictive feedforward control partly based on the target's derivatives. In contrast, the force oscillation was weakly coherent, but in phase, with high-frequency targets, suggesting control mainly based on a target's rhythm.

  1. In vivo time-resolved microtomography reveals the mechanics of the blowfly flight motor.

    Directory of Open Access Journals (Sweden)

    Simon M Walker

    2014-03-01

    Full Text Available Dipteran flies are amongst the smallest and most agile of flying animals. Their wings are driven indirectly by large power muscles, which cause cyclical deformations of the thorax that are amplified through the intricate wing hinge. Asymmetric flight manoeuvres are controlled by 13 pairs of steering muscles acting directly on the wing articulations. Collectively the steering muscles account for <3% of total flight muscle mass, raising the question of how they can modulate the vastly greater output of the power muscles during manoeuvres. Here we present the results of a synchrotron-based study performing micrometre-resolution, time-resolved microtomography on the 145 Hz wingbeat of blowflies. These data represent the first four-dimensional visualizations of an organism's internal movements on sub-millisecond and micrometre scales. This technique allows us to visualize and measure the three-dimensional movements of five of the largest steering muscles, and to place these in the context of the deforming thoracic mechanism that the muscles actuate. Our visualizations show that the steering muscles operate through a diverse range of nonlinear mechanisms, revealing several unexpected features that could not have been identified using any other technique. The tendons of some steering muscles buckle on every wingbeat to accommodate high amplitude movements of the wing hinge. Other steering muscles absorb kinetic energy from an oscillating control linkage, which rotates at low wingbeat amplitude but translates at high wingbeat amplitude. Kinetic energy is distributed differently in these two modes of oscillation, which may play a role in asymmetric power management during flight control. Structural flexibility is known to be important to the aerodynamic efficiency of insect wings, and to the function of their indirect power muscles. We show that it is integral also to the operation of the steering muscles, and so to the functional flexibility of the

  2. In vivo time-resolved microtomography reveals the mechanics of the blowfly flight motor.

    Science.gov (United States)

    Walker, Simon M; Schwyn, Daniel A; Mokso, Rajmund; Wicklein, Martina; Müller, Tonya; Doube, Michael; Stampanoni, Marco; Krapp, Holger G; Taylor, Graham K

    2014-03-01

    Dipteran flies are amongst the smallest and most agile of flying animals. Their wings are driven indirectly by large power muscles, which cause cyclical deformations of the thorax that are amplified through the intricate wing hinge. Asymmetric flight manoeuvres are controlled by 13 pairs of steering muscles acting directly on the wing articulations. Collectively the steering muscles account for flight muscle mass, raising the question of how they can modulate the vastly greater output of the power muscles during manoeuvres. Here we present the results of a synchrotron-based study performing micrometre-resolution, time-resolved microtomography on the 145 Hz wingbeat of blowflies. These data represent the first four-dimensional visualizations of an organism's internal movements on sub-millisecond and micrometre scales. This technique allows us to visualize and measure the three-dimensional movements of five of the largest steering muscles, and to place these in the context of the deforming thoracic mechanism that the muscles actuate. Our visualizations show that the steering muscles operate through a diverse range of nonlinear mechanisms, revealing several unexpected features that could not have been identified using any other technique. The tendons of some steering muscles buckle on every wingbeat to accommodate high amplitude movements of the wing hinge. Other steering muscles absorb kinetic energy from an oscillating control linkage, which rotates at low wingbeat amplitude but translates at high wingbeat amplitude. Kinetic energy is distributed differently in these two modes of oscillation, which may play a role in asymmetric power management during flight control. Structural flexibility is known to be important to the aerodynamic efficiency of insect wings, and to the function of their indirect power muscles. We show that it is integral also to the operation of the steering muscles, and so to the functional flexibility of the insect flight motor.

  3. Inhibition mechanisms of hemoglobin, immunoglobulin G, and whole blood in digital and real-time PCR.

    Science.gov (United States)

    Sidstedt, Maja; Hedman, Johannes; Romsos, Erica L; Waitara, Leticia; Wadsö, Lars; Steffen, Carolyn R; Vallone, Peter M; Rådström, Peter

    2018-04-01

    Blood samples are widely used for PCR-based DNA analysis in fields such as diagnosis of infectious diseases, cancer diagnostics, and forensic genetics. In this study, the mechanisms behind blood-induced PCR inhibition were evaluated by use of whole blood as well as known PCR-inhibitory molecules in both digital PCR and real-time PCR. Also, electrophoretic mobility shift assay was applied to investigate interactions between inhibitory proteins and DNA, and isothermal titration calorimetry was used to directly measure effects on DNA polymerase activity. Whole blood caused a decrease in the number of positive digital PCR reactions, lowered amplification efficiency, and caused severe quenching of the fluorescence of the passive reference dye 6-carboxy-X-rhodamine as well as the double-stranded DNA binding dye EvaGreen. Immunoglobulin G was found to bind to single-stranded genomic DNA, leading to increased quantification cycle values. Hemoglobin affected the DNA polymerase activity and thus lowered the amplification efficiency. Hemoglobin and hematin were shown to be the molecules in blood responsible for the fluorescence quenching. In conclusion, hemoglobin and immunoglobulin G are the two major PCR inhibitors in blood, where the first affects amplification through a direct effect on the DNA polymerase activity and quenches the fluorescence of free dye molecules, and the latter binds to single-stranded genomic DNA, hindering DNA polymerization in the first few PCR cycles. Graphical abstract PCR inhibition mechanisms of hemoglobin and immunoglobulin G (IgG). Cq quantification cycle, dsDNA double-stranded DNA, ssDNA single-stranded DNA.

  4. Introduction of a quantum of time (``chronon``) and its consequences for quantum mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Farias, R H.A. [LNLS - Laboratorio Nacional de Luz Sincrotron, Campinas, S.P. (Brazil); Recami, E [Facolta di Ingegneria, Universita Statale di Bergamo, Bergamo (Italy)

    1998-07-01

    We discuss the consequences of the introduction of a quantum of time {tau}{sub 0} in the formalism of non-relativistic quantum mechanics, by referring ourselves, in particular, to the theory of the chronon as proposed by P. Caldirola. Such an interesting ``finite difference`` theory, forwards - at the classical level - a solution for the motion of a particle endowed with a non-negligible charge in an external electromagnetic field, overcoming all the known difficulties met by Abraham-Lorentz`s and Dirac`s approaches (and even allowing a clear answer to the question whether a free falling charged particle does or does not emit radiation), and - at the quantum level - yields a remarkable mass spectrum for leptons. After having briefly reviewed Caldirola`s approach, our first aim is to work out, discuss, and compare to one another the new representations of Quantum Mechanics (QM) resulting from it, in the Schroedinger, Heisenberg and density-operator (Liouville-von Neumann) pictures, respectively. Moreover, for each representation, three (retarded, symmetric and advanced) formulations are possible, which refer either to times t and t-{tau}{sub 0}, or to times t-{tau}{sub 0}/2 and t+{tau}{sub 0}/2, or to times t and t+{tau}{sub 0}, respectively. It is interesting to notice that, when the chronon tends to zero, the ordinary QM is obtained as the limiting case of the ``symmetric`` formulation only; while the ``retarded`` one does naturally appear to describe QM with friction, i.e., to describe dissipative quantum systems (like a particle moving in an absorbing medium). In this sense, discretized QM is much richer than the ordinary one. We also obtain the (retarded) finite-difference Schroedinger equation within the Feynman path integral approach, and study some of its relevant solutions. We then derive the time-evolution operators of this discrete theory, and use them to get the finite-difference Heisenberg equations. When discussing the mutual compatibility of the

  5. Los espacios compartidos ("Shared Space"

    Directory of Open Access Journals (Sweden)

    Mateus Porto Schettino

    2008-07-01

    The "Shared Space" concept was formally defined when the European Project with this title took place, as part of the Interreg IIIB, North Sea Program. "Shared Space" initiated at 2004 and it's time as a project partly financed by the European Union finish at 2008, after having promoted seven "pilot projects" at Germany, Belgium, Denmark, Holland and England. Nevertheless, Shared Space, it's just a new name for a technique with decades of history, developed fundamentally in Holland and which implemented new criteria for traffic regulation and public space design, were based on all traffic signs elimination and on the spatial integration of all different street users. To analyze Shared Space's projects construction and operation experience, and evaluate their possible application in some Spanish city centres is this paper main objective.

  6. Mechanics

    CERN Document Server

    Hartog, J P Den

    1961-01-01

    First published over 40 years ago, this work has achieved the status of a classic among introductory texts on mechanics. Den Hartog is known for his lively, discursive and often witty presentations of all the fundamental material of both statics and dynamics (and considerable more advanced material) in new, original ways that provide students with insights into mechanical relationships that other books do not always succeed in conveying. On the other hand, the work is so replete with engineering applications and actual design problems that it is as valuable as a reference to the practicing e

  7. Influences of social reward experience on behavioral responses to drugs of abuse: Review of shared and divergent neural plasticity mechanisms for sexual reward and drugs of abuse.

    Science.gov (United States)

    Beloate, Lauren N; Coolen, Lique M

    2017-12-01

    Different factors influence the development of drug addiction in humans, including social reward experiences. In animals, experience with social rewards, such as sexual behavior, pair bonding, social and environmental enrichment, can be protective. However, loss or lack of social rewards can lead to a vulnerability to drug-seeking behavior. The effects of social reward experience on drug-seeking behavior are associated with changes in the neural pathways that control drug-related behavior. This review will provide an introduction and overview of the mesolimbic pathway and the influence of social reward experience on drug-seeking behavior in rodents. Moreover, the research from our laboratory on effects of sexual experience and loss of sex reward on psychostimulant and opiate reward will be reviewed. Finally, we will review current knowledge of the neural mechanisms that underlie these interactions. Investigations of the neural underpinnings by which social and drug rewards interact contribute to improved understanding of the neural basis of vulnerability for drug addiction and reward-related behaviors in general. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Shared decision-making: is it time to obtain informed consent before radiologic examinations utilizing ionizing radiation? Legal and ethical implications.

    Science.gov (United States)

    Berlin, Leonard

    2014-03-01

    Concerns about the possibility of developing cancer due to diagnostic imaging examinations utilizing ionizing radiation exposure are increasing. Research studies of survivors of atomic bomb explosions, nuclear reactor accidents, and other unanticipated exposures to similar radiation have led to varying conclusions regarding the stochastic effects of radiation exposure. That high doses of ionizing radiation cause cancer in humans is generally accepted, but the question of whether diagnostic levels of radiation cause cancer continues to be hotly debated. It cannot be denied that overexposure to ionizing radiation beyond a certain threshold, which has not been exactly determined, does generate cancer. This causes a dilemma: what should patients be informed about the possibility that a CT or similar examination might cause cancer later in life? At present, there is no consensus in the radiology community as to whether informed consent must be obtained from a patient before the patient undergoes a CT or similar examination. The author analyzes whether there is a legal duty mandating radiologists to obtain such informed consent but also, irrespective of the law, whether there an ethical duty that compels radiologists to inform patients of potential adverse effects of ionizing radiation. Over the past decade, there has been a noticeable shift from a benevolent, paternalistic approach to medical care to an autonomy-based, shared-decision-making approach, whereby patient and physician work as partners in determining what is medically best for the patient. Radiologists should discuss the benefits and hazards of imaging with their patients. Copyright © 2014. Published by Elsevier Inc.

  9. Statistical mechanics of a time-homogeneous system of money and antimoney

    Science.gov (United States)

    Schmitt, Matthias; Schacker, Andreas; Braun, Dieter

    2014-03-01

    Financial crises appear throughout human history. While there are many schools of thought on what the actual causes of such crises are, it has been suggested that the creation of credit money might be a source of financial instability. We discuss how the credit mechanism in a system of fractional reserve banking leads to non-local transfers of purchasing power that also affect non-involved agents. To overcome this issue, we impose the local symmetry of time homogeneity on the monetary system. A bi-currency system of non-bank assets (money) and bank assets (antimoney) is considered. A payment is either made by passing on money or by receiving antimoney. As a result, a free floating exchange rate between non-bank assets and bank assets is established. Credit creation is replaced by the simultaneous transfer of money and antimoney at a negotiated exchange rate. This is in contrast to traditional discussions of full reserve banking, which stalls creditary lending. With money and antimoney, the problem of credit crunches is mitigated while a full time symmetry of the monetary system is maintained. As a test environment for such a monetary system, we discuss an economy of random transfers. Random transfers are a strong criterion to probe the stability of monetary systems. The analysis using statistical physics provides analytical solutions and confirms that a money-antimoney system could be functional. Equally important to the probing of the stability of such a monetary system is the question of how to implement the credit default dynamics. This issue remains open.

  10. Statistical mechanics of a time-homogeneous system of money and antimoney

    International Nuclear Information System (INIS)

    Schmitt, Matthias; Schacker, Andreas; Braun, Dieter

    2014-01-01

    Financial crises appear throughout human history. While there are many schools of thought on what the actual causes of such crises are, it has been suggested that the creation of credit money might be a source of financial instability. We discuss how the credit mechanism in a system of fractional reserve banking leads to non-local transfers of purchasing power that also affect non-involved agents. To overcome this issue, we impose the local symmetry of time homogeneity on the monetary system. A bi-currency system of non-bank assets (money) and bank assets (antimoney) is considered. A payment is either made by passing on money or by receiving antimoney. As a result, a free floating exchange rate between non-bank assets and bank assets is established. Credit creation is replaced by the simultaneous transfer of money and antimoney at a negotiated exchange rate. This is in contrast to traditional discussions of full reserve banking, which stalls creditary lending. With money and antimoney, the problem of credit crunches is mitigated while a full time symmetry of the monetary system is maintained. As a test environment for such a monetary system, we discuss an economy of random transfers. Random transfers are a strong criterion to probe the stability of monetary systems. The analysis using statistical physics provides analytical solutions and confirms that a money–antimoney system could be functional. Equally important to the probing of the stability of such a monetary system is the question of how to implement the credit default dynamics. This issue remains open

  11. On Converting Secret Sharing Scheme to Visual Secret Sharing Scheme

    Directory of Open Access Journals (Sweden)

    Wang Daoshun

    2010-01-01

    Full Text Available Abstract Traditional Secret Sharing (SS schemes reconstruct secret exactly the same as the original one but involve complex computation. Visual Secret Sharing (VSS schemes decode the secret without computation, but each share is m times as big as the original and the quality of the reconstructed secret image is reduced. Probabilistic visual secret sharing (Prob.VSS schemes for a binary image use only one subpixel to share the secret image; however the probability of white pixels in a white area is higher than that in a black area in the reconstructed secret image. SS schemes, VSS schemes, and Prob. VSS schemes have various construction methods and advantages. This paper first presents an approach to convert (transform a -SS scheme to a -VSS scheme for greyscale images. The generation of the shadow images (shares is based on Boolean XOR operation. The secret image can be reconstructed directly by performing Boolean OR operation, as in most conventional VSS schemes. Its pixel expansion is significantly smaller than that of VSS schemes. The quality of the reconstructed images, measured by average contrast, is the same as VSS schemes. Then a novel matrix-concatenation approach is used to extend the greyscale -SS scheme to a more general case of greyscale -VSS scheme.

  12. Rethinking the Sharing Economy

    DEFF Research Database (Denmark)

    Kornberger, Martin; Leixnering, Stephan; Meyer, Renate

    2017-01-01

    Our paper focuses on a non-standard sharing example that harbors the potential to disrupt received wisdom on the sharing economy. While originally entering the field to analyze, broadly from a governance perspective, how the 2015 refugee crisis was handled in Vienna, Austria, we found that the no...... of sharing: economic and moral. Our paper contributes to this Special Issue of the Academy of Management Discoveries by highlighting and explaining the two-fold economic and moral nature of sharing and the organization of sharing between movement and platform....... sharing of resources (i.e., the economic dimension): the sharing of a distinct concern (i.e., the moral dimension of sharing). Our discovery exemplifies such a moral dimension that is rather different from the status quo materialistic treatments focusing on economic transactions and property rights...

  13. Job Sharing in Education.

    Science.gov (United States)

    Davidson, Wilma; Kline, Susan

    1979-01-01

    The author presents the advantages of job sharing for all school personnel, saying that education is particularly adaptable to this new form of employment. Current job sharing programs in Massachusetts, California, and New Jersey schools are briefly discussed. (SJL)

  14. Production sharing agreements

    International Nuclear Information System (INIS)

    1994-01-01

    This paper, which was presented at the Production Sharing Agreement seminar, discusses economic rent, negotiations, trends in fiscal system development, and concessionary systems. Production sharing contracts, risk service contracts, joint ventures and the global market are examined. (UK)

  15. Real-time deformations of organ based on structural mechanics for surgical simulators

    Science.gov (United States)

    Nakaguchi, Toshiya; Tagaya, Masashi; Tamura, Nobuhiko; Tsumura, Norimichi; Miyake, Yoichi

    2006-03-01

    This research proposes the deformation model of organs for the development of the medical training system using Virtual Reality (VR) technology. First, the proposed model calculates the strains of coordinate axis. Secondly, the deformation is obtained by mapping the coordinate of the object to the strained coordinate. We assume the beams in the coordinate space to calculate the strain of the coordinate axis. The forces acting on the object are converted to the forces applied to the beams. The bend and the twist of the beams are calculated based on the theory of structural mechanics. The bend is derived by the finite element method. We propose two deformation methods which differ in the position of the beams in the coordinate space. One method locates the beams along the three orthogonal axes (x, y, z). Another method locates the beam in the area where the deformation is large. In addition, the strain of the coordinate axis is attenuated in proportion to the distance from the point of action to consider the attenuation of the stress which is a viscoelastic feature of the organs. The proposed model needs less computational cost compared to the conventional deformation method since our model does not need to divide the object into the elasticity element. The proposed model was implemented in the laparoscopic surgery training system, and a real-time deformation can be realized.

  16. Mechanical Properties, Short Time Creep, and Fatigue of an Austenitic Steel

    Directory of Open Access Journals (Sweden)

    Josip Brnic

    2016-04-01

    Full Text Available The correct choice of a material in the process of structural design is the most important task. This study deals with determining and analyzing the mechanical properties of the material, and the material resistance to short-time creep and fatigue. The material under consideration in this investigation is austenitic stainless steel X6CrNiTi18-10. The results presenting ultimate tensile strength and 0.2 offset yield strength at room and elevated temperatures are displayed in the form of engineering stress-strain diagrams. Besides, the creep behavior of the steel is presented in the form of creep curves. The material is consequently considered to be creep resistant at temperatures of 400 °C and 500 °C when subjected to a stress which is less than 0.9 of the yield strength at the mentioned temperatures. Even when the applied stress at a temperature of 600 °C is less than 0.5 of the yield strength, the steel may be considered as resistant to creep. Cyclic tensile fatigue tests were carried out at stress ratio R = 0.25 using a servo-pulser machine and the results were recorded. The analysis shows that the stress level of 434.33 MPa can be adopted as a fatigue limit. The impact energy was also determined and the fracture toughness assessed.

  17. Modelling the thermal quenching mechanism in quartz based on time-resolved optically stimulated luminescence

    International Nuclear Information System (INIS)

    Pagonis, V.; Ankjaergaard, C.; Murray, A.S.; Jain, M.; Chen, R.; Lawless, J.; Greilich, S.

    2010-01-01

    This paper presents a new numerical model for thermal quenching in quartz, based on the previously suggested Mott-Seitz mechanism. In the model electrons from a dosimetric trap are raised by optical or thermal stimulation into the conduction band, followed by an electronic transition from the conduction band into an excited state of the recombination center. Subsequently electrons in this excited state undergo either a direct radiative transition into a recombination center, or a competing thermally assisted non-radiative process into the ground state of the recombination center. As the temperature of the sample is increased, more electrons are removed from the excited state via the non-radiative pathway. This reduction in the number of available electrons leads to both a decrease of the intensity of the luminescence signal and to a simultaneous decrease of the luminescence lifetime. Several simulations are carried out of time-resolved optically stimulated luminescence (TR-OSL) experiments, in which the temperature dependence of luminescence lifetimes in quartz is studied as a function of the stimulation temperature. Good quantitative agreement is found between the simulation results and new experimental data obtained using a single-aliquot procedure on a sedimentary quartz sample.

  18. Time-Resolved Micro PIV in the Pivoting Area of the Triflo Mechanical Heart Valve.

    Science.gov (United States)

    Vennemann, Bernhard M; Rösgen, Thomas; Carrel, Thierry P; Obrist, Dominik

    2016-09-01

    The Lapeyre-Triflo FURTIVA valve aims at combining the favorable hemodynamics of bioprosthetic heart valves with the durability of mechanical heart valves (MHVs). The pivoting region of MHVs is hemodynamically of special interest as it may be a region of high shear stresses, combined with areas of flow stagnation. Here, platelets can be activated and may form a thrombus which in the most severe case can compromise leaflet mobility. In this study we set up an experiment to replicate the pulsatile flow in the aortic root and to study the flow in the pivoting region under physiological hemodynamic conditions (CO = 4.5 L/min / CO = 3.0 L/min, f = 60 BPM). It was found that the flow velocity in the pivoting region could reach values close to that of the bulk flow during systole. At the onset of diastole the three valve leaflets closed in a very synchronous manner within an average closing time of 55 ms which is much slower than what has been measured for traditional bileaflet MHVs. Hot spots for elevated viscous shear stresses were found at the flanges of the housing and the tips of the leaflet ears. Systolic VSS was maximal during mid-systole and reached levels of up to 40 Pa.

  19. Mechanical Properties, Short Time Creep, and Fatigue of an Austenitic Steel.

    Science.gov (United States)

    Brnic, Josip; Turkalj, Goran; Canadija, Marko; Lanc, Domagoj; Krscanski, Sanjin; Brcic, Marino; Li, Qiang; Niu, Jitai

    2016-04-20

    The correct choice of a material in the process of structural design is the most important task. This study deals with determining and analyzing the mechanical properties of the material, and the material resistance to short-time creep and fatigue. The material under consideration in this investigation is austenitic stainless steel X6CrNiTi18-10. The results presenting ultimate tensile strength and 0.2 offset yield strength at room and elevated temperatures are displayed in the form of engineering stress-strain diagrams. Besides, the creep behavior of the steel is presented in the form of creep curves. The material is consequently considered to be creep resistant at temperatures of 400 °C and 500 °C when subjected to a stress which is less than 0.9 of the yield strength at the mentioned temperatures. Even when the applied stress at a temperature of 600 °C is less than 0.5 of the yield strength, the steel may be considered as resistant to creep. Cyclic tensile fatigue tests were carried out at stress ratio R = 0.25 using a servo-pulser machine and the results were recorded. The analysis shows that the stress level of 434.33 MPa can be adopted as a fatigue limit. The impact energy was also determined and the fracture toughness assessed.

  20. Analytical Method to Estimate Fatigue Life Time Duration in Service for Runner Blade Mechanism of Kaplan Turbines

    Directory of Open Access Journals (Sweden)

    Ana – Maria Budai

    2010-10-01

    Full Text Available The paper present an analytical method that can be used to determianted fatigue life time duration in service for runner blade mechanism of Kaplan turbines. The study was made for lever button of runer blade mechanism using two analytical relation to calculate the maximum number of stress cycles whereupon the mechanism work without any damage. To estimate fatigue life time duration will be used a formula obtained from one of most comon cumulative damage methodology taking in consideration the real exploatation conditions of a specified Kapaln turbine.

  1. Genome-Wide Progesterone Receptor Binding: Cell Type-Specific and Shared Mechanisms in T47D Breast Cancer Cells and Primary Leiomyoma Cells

    Science.gov (United States)

    Huang, Lei; Owen, Jonas K.; Xie, Anna; Navarro, Antonia; Monsivais, Diana; Coon V, John S.; Kim, J. Julie; Dai, Yang; Bulun, Serdar E.

    2012-01-01

    Background Progesterone, via its nuclear receptor (PR), exerts an overall tumorigenic effect on both uterine fibroid (leiomyoma) and breast cancer tissues, whereas the antiprogestin RU486 inhibits growth of these tissues through an unknown mechanism. Here, we determined the interaction between common or cell-specific genome-wide binding sites of PR and mRNA expression in RU486-treated uterine leiomyoma and breast cancer cells. Principal Findings ChIP-sequencing revealed 31,457 and 7,034 PR-binding sites in breast cancer and uterine leiomyoma cells, respectively; 1,035 sites overlapped in both cell types. Based on the chromatin-PR interaction in both cell types, we statistically refined the consensus progesterone response element to G•ACA• • •TGT•C. We identified two striking differences between uterine leiomyoma and breast cancer cells. First, the cis-regulatory elements for HSF, TEF-1, and C/EBPα and β were statistically enriched at genomic RU486/PR-targets in uterine leiomyoma, whereas E2F, FOXO1, FOXA1, and FOXF sites were preferentially enriched in breast cancer cells. Second, 51.5% of RU486-regulated genes in breast cancer cells but only 6.6% of RU486-regulated genes in uterine leiomyoma cells contained a PR-binding site within 5 kb from their transcription start sites (TSSs), whereas 75.4% of RU486-regulated genes contained a PR-binding site farther than 50 kb from their TSSs in uterine leiomyoma cells. RU486 regulated only seven mRNAs in both cell types. Among these, adipophilin (PLIN2), a pro-differentiation gene, was induced via RU486 and PR via the same regulatory region in both cell types. Conclusions Our studies have identified molecular components in a RU486/PR-controlled gene network involved in the regulation of cell growth, cell migration, and extracellular matrix function. Tissue-specific and common patterns of genome-wide PR binding and gene regulation may determine the therapeutic effects of antiprogestins in uterine fibroids and

  2. Job Sharing in Geography.

    Science.gov (United States)

    Kay, Jeanne

    1982-01-01

    Job sharing is an employment alternative in which two qualified individuals manage the responsibilities of a single position. Discusses the barriers to and the potential, advantages, disadvantages, pitfalls, and challenges of job sharing. Focuses on job sharing in the geography profession. (Author/JN)

  3. The Sharing Economy

    OpenAIRE

    Reinhold, Stephan; Dolnicar, Sara

    2017-01-01

    Peer-to-peer accommodation networks in general, and Airbnb in specific, are frequently referred to as part of the sharing economy. This chapter provides an overview of key characteristics of the sharing economy, discusses how these characteristics relate to peer-to-peer accommodation, and positions peer-to-peer accommodation networks within the sharing economy.

  4. Satisfaction and 'comparison sharing'

    DEFF Research Database (Denmark)

    Amilon, Anna

    2009-01-01

    the probability of satisfaction. Results show that comparison sharing impacts satisfaction for women, and that those women who share more equally than their peers are more likely to be satisfied, whereas comparison sharing has no influence on satisfaction for men. Also, parents are less likely to be satisfied...

  5. Shared Decision Making for Better Schools.

    Science.gov (United States)

    Brost, Paul

    2000-01-01

    Delegating decision making to those closest to implementation can result in better decisions, more support for improvement initiatives, and increased student performance. Shared decision making depends on capable school leadership, a professional community, instructional guidance mechanisms, knowledge and skills, information sharing, power, and…

  6. Analysis of the feasibility of inclusion of decentralised renewable electricity systems into a mandated market share mechanism for China. Executive summary

    International Nuclear Information System (INIS)

    Van der Linden, N.H.; Junfeng, L.; Keyun, D.; Martens, J.W.; Ramani, K.V.; Sicheng, W.; Shutian, W.; Tak, C. van der

    2003-09-01

    , simplified procedures have been developed for verifying the number of DRES sold and the operational status of the systems. The analyses shows that inclusion of stand alone PV and wind into the MMS is not feasible because the required verification procedures for these technologies appear to be too costly and the additional electricity generated is only significant if the premium price of wind and PV is some 100 times higher compared to grid connected RE technologies. For mini-hydro, however, it is concluded that inclusion into the MMS is feasible and recommendable

  7. Analysis of the feasibility of inclusion of decentralised renewable electricity systems into a mandated market share mechanism for China. Final Report

    International Nuclear Information System (INIS)

    Van der Linden, N.H.; Junfeng, L.; Keyun, D.; Martens, J.W.; Ramani, K.V.; Sicheng, W.; Shutian, W.; Tak, C. van der

    2003-10-01

    , simplified procedures have been developed for verifying the number of DRES sold and the operational status of the systems. The analyses shows that inclusion of stand alone PV and wind into the MMS is not feasible because the required verification procedures for these technologies appear to be too costly and the additional electricity generated is only significant if the premium price of wind and PV is some 100 times higher compared to grid connected RE technologies. For mini-hydro, however, it is concluded that inclusion into the MMS is feasible and recommendable

  8. Real time monitoring in-vivo micro-environment through the wound heal mechanism

    Science.gov (United States)

    Yan, Jack

    2013-02-01

    One of the In-vivo system's challenge is real time display the sensing information. Usually Ultrasound, CT, MRI, PET are used to get the internal information, this thesis proposed another approach to address the display challenge. Special nano-particles are in-taken or injected to living subject (usually into blood circulation) to sense and collect psychological information when the active particles pass through the tissues of interest. Using the wound healing mechanism, these activated particles (Information collected) can be drifted out to the wound area and adhibited close to the skin, then skin can show different color if the activated particles are concentrated enough in the specific area to create a skin screen. The skin screen can display the blood status, internal organ's temperature, pressure depending the nano-particles' function and their pathway. This approach can also be used to display in-body video if the particles are sensitive and selective enough. In the future, the skin screen can be bio-computer's monitor. The wound healing in an animal model normally divides in four phase: Hemostasis, Inflammation, Proliferation and Maturation. Hemostasis phase is to form a stable clot sealing the damaged vessel. Inflammation phase causes the blood vessels to become leaky releasing plasma and PMN's (polymorphonucleocytes) into the surrounding tissue and provide the first line of defense against infection. Proliferation phase involves replacement of dermal tissues and sometimes subdermal tissues in deeper wounds as well as contraction of the wound. Maturation phase remodels the dermal tissues mainly by fibroblast to produce greater tensile strength. The skin screen wound will be carefully controlled to be triggered at dermis layer.

  9. Final Technical Report of project: "Contactless Real-Time Monitoring of Paper Mechanical Behavior During Papermaking"

    Energy Technology Data Exchange (ETDEWEB)

    Emmanuel Lafond; Paul Ridgway; Ted Jackson; Rick Russo; Ken Telschow; Vance Deason; Yves Berthelot; David Griggs; Xinya Zhang; Gary Baum

    2005-08-30

    The early precursors of laser ultrasonics on paper were Prof. Y. Berthelot from the Georgia Institute of Technology/Mechanical Engineering department, and Prof. P. Brodeur from the Institute of Paper Science and Technology, both located in Atlanta, Georgia. The first Ph.D. thesis that shed quite some light on the topic, but also left some questions unanswered, was completed by Mont A. Johnson in 1996. Mont Johnson was Prof. Berthelot's student at Georgia Tech. In 1997 P. Brodeur proposed a project involving himself, Y. Berthelot, Dr. Ken Telschow and Mr. Vance Deason from INL, Honeywell-Measurex and Dr. Rick Russo from LBNL. The first time the proposal was not accepted and P. Brodeur decided to re-propose it without the involvement from LBNL. Rick Russo proposed a separate project on the same topic on his side. Both proposals were finally accepted and work started in the fall of 1997 on the two projects. Early on, the biggest challenge was to find an optical detection method which could detect laser-induced displacements of the web surface that are of the order of .1 micron in the ultrasonic range. This was to be done while the web was having an out-of-plane amplitude of motion in the mm range due to web flutter; while moving at 10 m/s to 30 m/s in the plane of the web, on the paper machine. Both teams grappled with the same problems and tried similar methods in some cases, but came up with two similar but different solutions one year later. The IPST, GT, INL team found that an interferometer made by Lasson Technologies Inc. using the photo-induced electro-motive force in Gallium Arsenide was able to detect ultrasonic waves up to 12-15 m/s. It also developed in house an interferometer using the Two-Wave Mixing effect in photorefractive crystals that showed good promises for on-line applications, and experimented with a scanning mirror to reduce motion-induced texture noise from the web and improve signal to noise ratio. On its side, LBNL had the idea to

  10. Borrowing brainpower - sharing insecurities

    DEFF Research Database (Denmark)

    Wegener, Charlotte; Meier, Ninna; Ingerslev, Karen

    2016-01-01

    Academic writing is a vital, yet complex skill that must be developed within a doctoral training process. In addition, becoming an academic researcher is a journey of changing sense of self and identity. Through analysis of a group session, we show how the feedback of peers addresses questions...... of structure and writing style along with wider issues of researcher identity. Thus, peer learning is demonstrated as a process of simultaneously building a text and an identity as scholarly researcher. The paper advocates ‘borrowing brainpower’ from peers in order to write better texts and, at the same time......, ‘share insecurities’ during the development of the researcher identity. Based on a distributed notion of peer learning and identity, we point to the need for further research into the everyday activities of doctoral writing groups in order to understand the dynamic relationship between production of text...

  11. A Shared Scratchpad Memory with Synchronization Support

    DEFF Research Database (Denmark)

    Hansen, Henrik Enggaard; Maroun, Emad Jacob; Kristensen, Andreas Toftegaard

    2017-01-01

    Multicore processors usually communicate via shared memory, which is backed up by a shared level 2 cache and a cache coherence protocol. However, this solution is not a good fit for real-time systems, where we need to provide tight guarantees on execution and memory access times. In this paper, we...... propose a shared scratchpad memory as a time-predictable communication and synchronization structure, instead of the level 2 cache. The shared on-chip memory is accessed via a time division multiplexing arbiter, isolating the execution time of load and store instructions between processing cores....... Furthermore, the arbiter supports an extended time slot where an atomic load and store instruction can be executed to implement synchronization primitives. In the evaluation we show that a shared scratchpad memory is an efficient communication structure for a small number of processors; in our setup, 9 cores...

  12. A novel local recycling mechanism that enhances enteric bioavailability of flavonoids and prolongs their residence time in the gut.

    Science.gov (United States)

    Xia, Bijun; Zhou, Qiong; Zheng, Zhijie; Ye, Ling; Hu, Ming; Liu, Zhongqiu

    2012-11-05

    Recycling in the gastrointestinal tract is important for endogenous substances such as bile acids and for xenobiotics such as flavonoids. Although both enterohepatic and enteric recycling mechanisms are well recognized, no one has discussed the third recycling mechanism for glucuronides: local recycling. The intestinal absorption and metabolism of wogonin and wogonoside (wogonin-7-glucuronide) was characterized by using a four-site perfused rat intestinal model, and hydrolysis of wogonoside was measured in various enzyme preparations. In the perfusion model, the wogonoside and wogonin were interconverted in all four perfused segments. Absorption of wogonoside and conversion to its aglycon at the upper small intestine was inhibited in the presence of a glucuronidase inhibitor (saccharolactone) but was not inhibited by lactase phlorizin hydrolase (LPH) inhibitor gluconolactone or antibiotics. Further investigation indicated that hydrolysis of wogonoside in the blank intestinal perfusate was not correlated with bacterial counts. Kinetic studies indicated that K(m) values from blank duodenal and jejunal perfusate were essentially identical to the K(m) values from intestinal S9 fraction but were much higher (>2-fold) than those from the microbial enzyme extract. Lastly, jejunal perfusate and S9 fraction share the same optimal pH, which was different from those of fecal extract. In conclusion, local recycling of wogonin and wogonoside is the first demonstrated example that this novel mechanism is functional in the upper small intestine without significant contribution from bacteria β-glucuronidase.

  13. Annual Research Review: Reaction time variability in ADHD and autism spectrum disorders: measurement and mechanisms of a proposed trans-diagnostic phenotype

    Science.gov (United States)

    Karalunas, Sarah L.; Geurts, Hilde M.; Konrad, Kerstin; Bender, Stephan; Nigg, Joel T.

    2014-01-01

    Background Intraindividual variability in reaction time (RT) has received extensive discussion as an indicator of cognitive performance, a putative intermediate phenotype of many clinical disorders, and a possible trans-diagnostic phenotype that may elucidate shared risk factors for mechanisms of psychiatric illnesses. Scope and Methodology Using the examples of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorders (ASD), we discuss RT variability. We first present a new meta-analysis of RT variability in ASD with and without comorbid ADHD. We then discuss potential mechanisms that may account for RT variability and statistical models that disentangle the cognitive processes affecting RTs. We then report a second meta-analysis comparing ADHD and non-ADHD children on diffusion model parameters. We consider how findings inform the search for neural correlates of RT variability. Findings Results suggest that RT variability is increased in ASD only when children with comorbid ADHD are included in the sample. Furthermore, RT variability in ADHD is explained by moderate to large increases (d = 0.63–0.99) in the ex-Gaussian parameter τ and the diffusion parameter drift rate, as well as by smaller differences (d = 0.32) in the diffusion parameter of nondecision time. The former may suggest problems in state regulation or arousal and difficulty detecting signal from noise, whereas the latter may reflect contributions from deficits in motor organization or output. The neuroimaging literature converges with this multicomponent interpretation and also highlights the role of top-down control circuits. Conclusion We underscore the importance of considering the interactions between top-down control, state regulation (e.g. arousal), and motor preparation when interpreting RT variability and conclude that decomposition of the RT signal provides superior interpretive power and suggests mechanisms convergent with those implicated using other cognitive

  14. Successful Architectural Knowledge Sharing: Beware of Emotions

    Science.gov (United States)

    Poort, Eltjo R.; Pramono, Agung; Perdeck, Michiel; Clerc, Viktor; van Vliet, Hans

    This chapter presents the analysis and key findings of a survey on architectural knowledge sharing. The responses of 97 architects working in the Dutch IT Industry were analyzed by correlating practices and challenges with project size and success. Impact mechanisms between project size, project success, and architectural knowledge sharing practices and challenges were deduced based on reasoning, experience and literature. We find that architects run into numerous and diverse challenges sharing architectural knowledge, but that the only challenges that have a significant impact are the emotional challenges related to interpersonal relationships. Thus, architects should be careful when dealing with emotions in knowledge sharing.

  15. Dynamic quantum secret sharing

    International Nuclear Information System (INIS)

    Jia, Heng-Yue; Wen, Qiao-Yan; Gao, Fei; Qin, Su-Juan; Guo, Fen-Zhuo

    2012-01-01

    In this Letter we consider quantum secret sharing (QSS) between a sender and a dynamic agent group, called dynamic quantum secret sharing (DQSS). In the DQSS, the change of the agent group is allowable during the procedure of sharing classical and quantum information. Two DQSS schemes are proposed based on a special kind of entangled state, starlike cluster states. Without redistributing all the shares, the changed agent group can reconstruct the sender's secret by their cooperation. Compared with the previous quantum secret sharing scheme, our schemes are more flexible and suitable for practical applications. -- Highlights: ► We consider quantum secret sharing between a sender and a dynamic agent group, called dynamic quantum secret sharing (DQSS). ► In the DQSS, the change of the agent group is allowable during the procedure of sharing classical and quantum information. ► Two DQSS schemes are proposed based on a special kind of entangled state, starlike cluster states. ► Without redistributing all the shares, the changed agent group can reconstruct the sender's secret by their cooperation. ► Compared with the previous quantum secret sharing scheme, our schemes are more flexible and suitable for practical applications.

  16. Time evolution of some quantum-mechanical systems. Wavefunction cloning in evolving rotating systems. Finite range boundary conditions for time dependent Schroedinger Equation

    International Nuclear Information System (INIS)

    Arvieu, R.; Carbonell, J.; Gignoux, C.; Mangin-Brinet, M.; Rozmej, P.

    1997-01-01

    The time evolution of coherent rotational wave packets associated to a diatomic molecule or to a deformed nucleus has been studied. Assuming a rigid body dynamics the J(J+1) law leads to a mechanism of cloning: the way function is divided into wave packets identical to the initial one at specific time. Applications are studied for a nuclear wave packed formed by Coulomb excitation. Exact boundary conditions at finite distance for the solution of the time-dependent Schroedinger equation are derived. A numerical scheme based on Crank-Nicholson method is proposed to illustrate its applicability in several examples. (authors)

  17. Nonlinear time reversal signal processing techniques applied to acousto-mechanical imaging of complex materials

    Czech Academy of Sciences Publication Activity Database

    Dos Santos, S.; Dvořáková, Zuzana; Caliez, M.; Převorovský, Zdeněk

    2015-01-01

    Roč. 138, č. 3 (2015) ISSN 0001-4966 Institutional support: RVO:61388998 Keywords : acousto-mechanical characterization of skin aging * nonlinear elastic wave spectroscopy (NEWS) * PM-space statistical approach Subject RIV: BI - Acoustics

  18. Knowledge Management for Shared Awareness

    Science.gov (United States)

    2013-05-01

    knowledge derived from experiences that can be communicated through mechanisms such as storytelling , debriefing etc., or summarized in databases...patterned on the neural architecture of the brain . Neural nets often consist of a large number of nodes connected by links that transmit signals...that allow speech generation by a computer. Storytelling : The use of stories in organizations as a way of sharing knowledge and helping learning

  19. Shared mechanisms among neurodegenerative diseases: from ...

    Indian Academy of Sciences (India)

    douglas arneson

    amyotrophic lateral sclerosis (ALS) are pressing health concerns in modern societies for which ... subsets of diseases, and a systematic review of the most current information ... (vesicle-associated membrane protein)-associated protein B) for ...

  20. Job sharing. Part 1.

    Science.gov (United States)

    Anderson, K; Forbes, R

    1989-01-01

    This article is the first of a three part series discussing the impact of nurses job sharing at University Hospital, London, Ontario. This first article explores the advantages and disadvantages of job sharing for staff nurses and their supervising nurse manager, as discussed in the literature. The results of a survey conducted on a unit with a large number of job sharing positions, concur with literature findings. The second article will present the evaluation of a pilot project in which two nurses job share a first line managerial position in the Operating Room. The third article will relate the effects of job sharing on women's perceived general well being. Job sharing in all areas, is regarded as a positive experience by both nurse and administrators.

  1. The Sharing Economy

    DEFF Research Database (Denmark)

    Avital, Michel; Carroll, John M.; Hjalmarsson, Anders

    2015-01-01

    The sharing economy is spreading rapidly worldwide in a number of industries and markets. The disruptive nature of this phenomenon has drawn mixed responses ranging from active conflict to adoption and assimilation. Yet, in spite of the growing attention to the sharing economy, we still do not know...... much about it. With the abundant enthusiasm about the benefits that the sharing economy can unleash and the weekly reminders about its dark side, further examination is required to determine the potential of the sharing economy while mitigating its undesirable side effects. The panel will join...... the ongoing debate about the sharing economy and contribute to the discourse with insights about how digital technologies are critical in shaping this turbulent ecosystem. Furthermore, we will define an agenda for future research on the sharing economy as it becomes part of the mainstream society as well...

  2. A Truth Serum for Sharing Rewards

    OpenAIRE

    Carvalho, Arthur; Larson, Kate

    2013-01-01

    We study a problem where a group of agents has to decide how a joint reward should be shared among them. We focus on settings where the share that each agent receives depends on the subjective opinions of its peers concerning that agent's contribution to the group. To this end, we introduce a mechanism to elicit and aggregate subjective opinions as well as for determining agents' shares. The intuition behind the proposed mechanism is that each agent who believes that the others are telling th...

  3. Mechanics

    CERN Document Server

    Chester, W

    1979-01-01

    When I began to write this book, I originally had in mind the needs of university students in their first year. May aim was to keep the mathematics simple. No advanced techniques are used and there are no complicated applications. The emphasis is on an understanding of the basic ideas and problems which require expertise but do not contribute to this understanding are not discussed. How­ ever, the presentation is more sophisticated than might be considered appropri­ ate for someone with no previous knowledge of the subject so that, although it is developed from the beginning, some previous acquaintance with the elements of the subject would be an advantage. In addition, some familiarity with element­ ary calculus is assumed but not with the elementary theory of differential equations, although knowledge of the latter would again be an advantage. It is my opinion that mechanics is best introduced through the motion of a particle, with rigid body problems left until the subject is more fully developed. Howev...

  4. Display Sharing: An Alternative Paradigm

    Science.gov (United States)

    Brown, Michael A.

    2010-01-01

    The current Johnson Space Center (JSC) Mission Control Center (MCC) Video Transport System (VTS) provides flight controllers and management the ability to meld raw video from various sources with telemetry to improve situational awareness. However, maintaining a separate infrastructure for video delivery and integration of video content with data adds significant complexity and cost to the system. When considering alternative architectures for a VTS, the current system's ability to share specific computer displays in their entirety to other locations, such as large projector systems, flight control rooms, and back supporting rooms throughout the facilities and centers must be incorporated into any new architecture. Internet Protocol (IP)-based systems also support video delivery and integration. IP-based systems generally have an advantage in terms of cost and maintainability. Although IP-based systems are versatile, the task of sharing a computer display from one workstation to another can be time consuming for an end-user and inconvenient to administer at a system level. The objective of this paper is to present a prototype display sharing enterprise solution. Display sharing is a system which delivers image sharing across the LAN while simultaneously managing bandwidth, supporting encryption, enabling recovery and resynchronization following a loss of signal, and, minimizing latency. Additional critical elements will include image scaling support, multi -sharing, ease of initial integration and configuration, integration with desktop window managers, collaboration tools, host and recipient controls. This goal of this paper is to summarize the various elements of an IP-based display sharing system that can be used in today's control center environment.

  5. Probabilistic Infinite Secret Sharing

    OpenAIRE

    Csirmaz, László

    2013-01-01

    The study of probabilistic secret sharing schemes using arbitrary probability spaces and possibly infinite number of participants lets us investigate abstract properties of such schemes. It highlights important properties, explains why certain definitions work better than others, connects this topic to other branches of mathematics, and might yield new design paradigms. A probabilistic secret sharing scheme is a joint probability distribution of the shares and the secret together with a colle...

  6. BBSRC Data Sharing Policy

    OpenAIRE

    Amanda Collis; David McAllister; Michael Ball

    2011-01-01

    BBSRC recognizes the importance of contributing to the growing international efforts in data sharing. BBSRC is committed to getting the best value for the funds we invest and believes that making research data more readily available will reinforce open scientific inquiry and stimulate new investigations and analyses. BBSRC supports the view that data sharing should be led by the scientific community and driven by scientific need. It should also be cost effective and the data shared should be ...

  7. Factors Impacting Knowledge Sharing

    DEFF Research Database (Denmark)

    Schulzmann, David; Slepniov, Dmitrij

    The purpose of this paper is to examine various factors affecting knowledge sharing at the R&D center of a Western MNE in China. The paper employs qualitative methodology and is based on the action research and case study research techniques. The findings of the paper advance our understanding...... about factors that affect knowledge sharing. The main emphasis is given to the discussion on how to improve knowledge sharing in global R&D organizations....

  8. Regulating the sharing economy

    OpenAIRE

    Erickson, Kristofer; Sorensen, Inge

    2016-01-01

    In this introductory essay, we explore definitions of the ‘sharing economy’, a concept indicating both social (relational, communitarian) and economic (allocative, profit-seeking) aspects which appear to be in tension. We suggest combining the social and economic logics of the sharing economy to focus on the central features of network enabled, aggregated membership in a pool of offers and demands (for goods, services, creative expressions). This definition of the sharing economy distinguishe...

  9. How emotions change time

    Directory of Open Access Journals (Sweden)

    Annett eSchirmer

    2011-10-01

    Full Text Available Experimental evidence suggests that emotions can both speed-up and slow-down the internal clock. Speeding-up has been observed for to-be-timed emotional stimuli that have the capacity to sustain attention, whereas slowing-down has been observed for to-be-timed neutral stimuli that are presented in the context of emotional distractors. These effects have been explained by mechanisms that involve changes in bodily arousal, attention or sentience. A review of these mechanisms suggests both merits and difficulties in the explanation of the emotion-timing link. Therefore, a hybrid mechanism involving stimulus-specific sentient representations is proposed as a candidate for mediating emotional influences on time. According to this proposal, emotional events enhance sentient representations, which in turn support temporal estimates. Emotional stimuli with a larger share in ones sentience are then perceived as longer than neutral stimuli with a smaller share.

  10. Phenomenology of experiential sharing

    DEFF Research Database (Denmark)

    León, Felipe; Zahavi, Dan

    2016-01-01

    The chapter explores the topic of experiential sharing by drawing on the early contributions of the phenomenologists Alfred Schutz and Gerda Walther. It is argued that both Schutz and Walther support, from complementary perspectives, an approach to experiential sharing that has tended to be overl......The chapter explores the topic of experiential sharing by drawing on the early contributions of the phenomenologists Alfred Schutz and Gerda Walther. It is argued that both Schutz and Walther support, from complementary perspectives, an approach to experiential sharing that has tended...

  11. A Data Sharing Story

    Directory of Open Access Journals (Sweden)

    Mercè Crosas

    2012-01-01

    Full Text Available From the early days of modern science through this century of Big Data, data sharing has enabled some of the greatest advances in science. In the digital age, technology can facilitate more effective and efficient data sharing and preservation practices, and provide incentives for making data easily accessible among researchers. At the Institute for Quantitative Social Science at Harvard University, we have developed an open-source software to share, cite, preserve, discover and analyze data, named the Dataverse Network. We share here the project’s motivation, its growth and successes, and likely evolution.

  12. Share your sweets

    DEFF Research Database (Denmark)

    Byrnit, Jill; Høgh-Olesen, Henrik; Makransky, Guido

    2015-01-01

    study to examine the sharing behavior of groups of captive chimpanzees and bonobos when introducing the same type of food (branches) manipulated to be of two different degrees of desirability (with or without syrup). Results showed that, the large majority of food transfers in both species came about...... as sharing in which group members were allowed to co-feed or remove food from the stock of the food possessor, and the introduction of high-value food resulted in more sharing, not less. Food sharing behavior differed between species in that chimpanzees displayed significantly more begging behavior than...

  13. Protection of Cultural Heritage in Urban Areas during Peace and Conflict Times from Threats to Risk Preparedness as a Shared Responsibility

    Science.gov (United States)

    Cimino, C.

    2013-07-01

    In times of economic hardship, the support given by specialized civil society organisations to public institutions in the protection of cultural heritage has often proved very useful, and there is evidence that their contribution is essential in times of conflicts and natural disasters, if well-designed plans and measures are organized efficiently, thoroughly tested and properly implemented. The 1954 Hague Convention for the Protection of Cultural Property in the Event of Armed Conflict (HC), its two Protocols and other international juridical instruments address these situations since decades, however, they remained widely not-applied in absence of proper regulatory instruments. In 2004, the Second Protocol of the Hague Convention (1999HP) entered into force and the Committee of the State Parties was formed. It became clear that a new trend started when, in 2009, draft Guidelines for the implementation of the 1999HP were issued. Meanwhile, WATCH, in partnership with the Council of the United Municipalitities of Jbail (Lebanon) and the Head of the Municipality of Mtskheta (Georgia) prepared a project proposal aimed to set a precedent in the governance of urban sites that are registered in the World Heritage List which are at risk of armed conflict. The project War Free World Heritage Listed Cities http://www.warfreeheritage.net/ was co-financed in 2010 with a grant within the framework of the EC CIUDAD programme and it is currently at an advanced level of implementation. This presentation will focus on achievements and contingencies faced during implementation as well as lessons learned that could be surely useful for pers pective applicants.

  14. It Takes Two: NASA and NOAA's Shared Path of Hurricane Science Flights with the Global Hawk. Time for the Research To Operations (R2O) Transition?

    Science.gov (United States)

    Emory, A. E.; Wick, G. A.; Dunion, J. P.; McLinden, M.; Schreier, M. M.; Black, P.; Hood, R. E.; Sippel, J.; Tallapragada, V.

    2017-12-01

    The impacts of Harvey, Irma, and Maria during the 2017 Atlantic hurricane season re-emphasized the critical need for accurate operational forecasts. The combined NASA East Pacific Origins and Characteristics of Hurricanes (EPOCH) and NOAA UAS field campaign during August 2017 was the fourth campaign in a series of dual agency partnerships between NASA and NOAA to improve forecasting accuracy in tropical cyclogenesis and rapid intensification. A brief history of Global Hawk (GH) hurricane field campaigns, including GRIP (2010), HS3 (2012-2014), NOAA-SHOUT (2015-2016) and EPOCH (2017), will show the incremental steps taken over the last eight years to bring the GH from a research platform to a candidate for operational hurricane reconnaissance. GH dropsondes were assimilated into the ECMWF and HWRF forecast models during the 2015-2016 NOAA SHOUT campaigns. EPOCH marked the first time that GH dropsondes were assimilated in real-time into NOAA's GFS forecast model. Early results show that assimilating dropsonde data significantly increases skill in predicting intensity change, which is game changing since the National Hurricane Center intensity error trend has remained virtually unchanged, particularly at 24 hours, over the last 25 years. The results from the past few years suggest that a paradigm shift of sampling the environment with a high-altitude, long-duration UAS like the GH that is capable of deploying up to 90 dropsondes ahead of and over the top of a developing or strengthening tropical cyclone could produce the best return on hurricane forecast predictions in subsequent years. Recommendations for the future, including lessons learned and the potential for R2O transition will be discussed.

  15. Timing Embryo Segmentation: Dynamics and Regulatory Mechanisms of the Vertebrate Segmentation Clock

    Science.gov (United States)

    Resende, Tatiana P.; Andrade, Raquel P.; Palmeirim, Isabel

    2014-01-01

    All vertebrate species present a segmented body, easily observed in the vertebrate column and its associated components, which provides a high degree of motility to the adult body and efficient protection of the internal organs. The sequential formation of the segmented precursors of the vertebral column during embryonic development, the somites, is governed by an oscillating genetic network, the somitogenesis molecular clock. Herein, we provide an overview of the molecular clock operating during somite formation and its underlying molecular regulatory mechanisms. Human congenital vertebral malformations have been associated with perturbations in these oscillatory mechanisms. Thus, a better comprehension of the molecular mechanisms regulating somite formation is required in order to fully understand the origin of human skeletal malformations. PMID:24895605

  16. Car sharing à la carte

    CERN Multimedia

    Anaïs Schaeffer

    2012-01-01

    Do you want to make your commute to CERN easier, while saving money at the same time? Would you prefer not to spend a quarter of an hour crawling round the CERN car parks looking for a space? If so, read on: this article might well be of great interest to you.   We would like to draw your attention to a well established, albeit sadly under-used, method of transport: car sharing. To promote car-sharing, the GS Department has stepped in to call on the services of the Swiss firm Green Monkeys which specialises in this user-friendly and intelligent transport scheme. The company’s slogan is:  “Car-sharing as you want, when you want and as much as you want”. The principle is very straightforward. To use this car-sharing facility, you simply complete your free online registration with Green Monkeys, providing the following details: your journey, departure time, arrival time and days of the week, and indicating whether you are a passenger or driver or both. &a...

  17. Classical and quantum-mechanical axioms with the higher time derivative formalism

    International Nuclear Information System (INIS)

    Kamalov, Timur

    2013-01-01

    A Newtonian mechanics model is essentially the model of a point body in an inertial reference frame. How to describe extended bodies in non-inertial (vibration) reference frames with the random initial conditions? One of the most generalized ways of descriptions (known as the higher derivatives formalism) consists in taking into account the infinite number of the higher temporal derivatives of the coordinates in the Lagrange function. Such formalism describing physical objects in the infinite dimensions space does not contradict to the quantum mechanics and infinite dimensions Hilbert space.

  18. One-Time URL: A Proximity Security Mechanism between Internet of Things and Mobile Devices.

    Science.gov (United States)

    Solano, Antonio; Dormido, Raquel; Duro, Natividad; González, Víctor

    2016-10-13

    The aim of this paper is to determine the physical proximity of connected things when they are accessed from a smartphone. Links between connected things and mobile communication devices are temporarily created by means of dynamic URLs (uniform resource locators) which may be easily discovered with pervasive short-range radio frequency technologies available on smartphones. In addition, a multi cross domain silent logging mechanism to allow people to interact with their surrounding connected things from their mobile communication devices is presented. The proposed mechanisms are based in web standards technologies, evolving our social network of Internet of Things towards the so-called Web of Things.

  19. Effect of Weathering Time on the Physical - Mechanical Properties and Color Change in Wood Flour/HDPE Composite

    Directory of Open Access Journals (Sweden)

    Behzad Kord

    2014-05-01

    Full Text Available This study was carried out to investigate the effect of weathering time on the physical and mechanical properties and color change in composite made of wood flour and high density polyethylene (HDPE. For this purpose, wood flour and polyethylene at a weight ratio of 60:40 with coupling agent were compounded in an internal mixer, and the samples were made in injection molding. Then, the weathering process by ultraviolet irradiation and water spray was done on the samples at different times of 250, 500, 1000 and 2000 hours in accelerated weathering apparatus. Finally, the physical and mechanical properties and color measurement of samples were tested, and compared with control samples. Results indicated that the flexural strength, flexural modulus, tensile strength and tensile modulus decreased with an increase in weathering time; however, the water absorption increased. Also, the yellowness of wood plastic samples decreased with an increase in weathering time and due to the lightness and color change increased.

  20. Correction of fatigue parameters of concrete using approximation of mechanical-Fracture parameters in time

    Czech Academy of Sciences Publication Activity Database

    Šimonová, H.; Keršner, Z.; Seitl, Stanislav; Pryl, D.; Pukl, R.

    -, č. 1 (2012), s. 57-59 ISSN 1213-3116 R&D Projects: GA ČR(CZ) GAP104/11/0833 Institutional support: RVO:68081723 Keywords : fatigue * concrete * correction * fracture parameters Subject RIV: JL - Materials Fatigue, Friction Mechanics

  1. A method for time-resolved measurements of the mechanics of phagocytic cups

    NARCIS (Netherlands)

    Irmscher, M.; Jong, de A.M.; Kress, H.; Prins, M.W.J.

    2013-01-01

    The internalization of matter by phagocytosis is of key importance in the defence against bacterial pathogens and in the control of cancerous tumour growth. Despite the fact that phagocytosis is an inherently mechanical process, little is known about the forces and energies that a cell requires for

  2. Drainage of pleural effusion in mechanically ventilated patients: time to measure chest wall compliance?

    Science.gov (United States)

    Formenti, Paolo; Umbrello, Michele; Piva, Ilaria R; Mistraletti, Giovanni; Zaniboni, Matteo; Spanu, Paolo; Noto, Andrea; Marini, John J; Iapichino, Gaetano

    2014-10-01

    Pleural effusion (PE) is commonly encountered in mechanically ventilated, critically ill patients and is generally addressed with evacuation or by fluid displacement using increased airway pressure (P(AW)). However, except when massive or infected, clear evidence is lacking to guide its management. The aim of this study was to investigate the effect of recruitment maneuvers and drainage of unilateral PE on respiratory mechanics, gas exchange, and lung volume. Fifteen critically ill and mechanically ventilated patients with unilateral PE were enrolled. A 3-step protocol (baseline, recruitment, and effusion drainage) was applied to patients with more than 400 mL of PE, as estimated by chest ultrasound. Predefined subgroup analysis compared patients with normal vs reduced chest wall compliance (C(CW)). Esophageal and P(AW)s, respiratory system, lung and C(CW)s, arterial blood gases, and end-expiratory lung volumes were recorded. In the whole case mix, neither recruitment nor drainage improved gas exchange, lung volume, or tidal mechanics. When C(CW) was normal, recruitment improved lung compliance (81.9 [64.8-104.1] vs 103.7 [91.5-111.7] mL/cm H2O, P drainage had no significant effect on total respiratory system mechanics or gas exchange, although it measurably increased lung volume (1717 vs 2150 mL, P drainage improved respiratory system and C(CW)s as well as lung volume (42.7 [38.9-50.0] vs 47.0 [43.8-63.3], P Drainage of a moderate-sized effusion should not be routinely performed in unselected population of critically ill patients. We suggest that measurement of C(CW) may help in the decision-making process. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Millennials and the Sharing Economy

    DEFF Research Database (Denmark)

    Ranzini, Giulia; Newlands, Gemma; Anselmi, Guido

    Report from the EU H2020 Research Project Ps2Share: Participation, Privacy, and Power in the Sharing Economy......Report from the EU H2020 Research Project Ps2Share: Participation, Privacy, and Power in the Sharing Economy...

  4. Time-based prospective memory in young children-Exploring executive functions as a developmental mechanism.

    Science.gov (United States)

    Kretschmer, Anett; Voigt, Babett; Friedrich, Sylva; Pfeiffer, Kathrin; Kliegel, Matthias

    2014-01-01

    The present study investigated time-based prospective memory (PM) during the transition from kindergarten/preschool to school age and applied mediation models to test the impact of executive functions (working memory, inhibitory control) and time monitoring on time-based PM development. Twenty-five preschool (age: M = 5.75, SD = 0.28) and 22 primary school children (age: M = 7.83, SD = 0.39) participated. To examine time-based PM, children had to play a computer-based driving game requiring them to drive a car on a road without hitting others cars (ongoing task) and to refill the car regularly according to a fuel gauge, which serves as clock equivalent (PM task). The level of gas that was still left in the fuel gauge was not displayed on the screen and children had to monitor it via a button press (time monitoring). Results revealed a developmental increase in time-based PM performance from preschool to school age. Applying the mediation models, only working memory was revealed to influence PM development. Neither inhibitory control alone nor the mediation paths leading from both executive functions to time monitoring could explain the link between age and time-based PM. Thus, results of the present study suggest that working memory may be one key cognitive process driving the developmental growth of time-based PM during the transition from preschool to school age.

  5. Mobile energy sharing futures

    DEFF Research Database (Denmark)

    Worgan, Paul; Knibbe, Jarrod; Plasencia, Diego Martinez

    2016-01-01

    We foresee a future where energy in our mobile devices can be shared and redistributed to suit our current task needs. Many of us are beginning to carry multiple mobile devices and we seek to re-evaluate the traditional view of a mobile device as only accepting energy. In our vision, we can...... sharing futures....

  6. 5G Spectrum Sharing

    OpenAIRE

    Nekovee, Maziar; Rudd, Richard

    2017-01-01

    In this paper an overview is given of the current status of 5G industry standards, spectrum allocation and use cases, followed by initial investigations of new opportunities for spectrum sharing in 5G using cognitive radio techniques, considering both licensed and unlicensed scenarios. A particular attention is given to sharing millimeter-wave frequencies, which are of prominent importance for 5G.

  7. NCSU Reactor Sharing Program

    International Nuclear Information System (INIS)

    Perez, P.B.

    1993-01-01

    The Nuclear Reactor Program at North Carolina State University provides the PULSTAR Research Reactor and associated facilities to eligible institutions with support, in part, from the Department of Energy Reactor Sharing Program. Participation in the NCSU Reactor Sharing Program continues to increase steadily with visitors ranging from advance high school physics and chemistry students to Ph.D. level research from neighboring universities

  8. 'An Arena for Sharing'

    DEFF Research Database (Denmark)

    la Cour, Karen; Ledderer, Loni; Hansen, Helle Ploug

    2015-01-01

    relatives). In-depth interviews were conducted in the participants' homes 1 month after the rehabilitation course. Data were analyzed by a constant comparative method. Results: Residential rehabilitation course was identified to serve as an "arena for sharing," underpinned by 3 dimensions of sharing...

  9. Spinorial space-time and the origin of Quantum Mechanics. The dynamical role of the physical vacuum

    International Nuclear Information System (INIS)

    Gonzalez-Mestres, Luis

    2016-01-01

    Is Quantum Mechanics really and ultimate principle of Physics described by a set of intrinsic exact laws? Are standard particles the ultimate constituents of matter? The two questions appear to be closely related, as a preonic structure of the physical vacuum would have an influence on the properties of quantum particles. Although the first preon models were just « quark-like » and assumed preons to be direct constituents of the conventional « elementary » particles, we suggested in 1995 that preons could instead be constituents of the physical vacuum (the superbradyon hypothesis). Standard particles would then be excitations of the preonic vacuum and have substantially different properties from those of preons themselves (critical speed…). The standard laws of Particle Physics would be approximate expressions generated from basic preon dynamics. In parallel, the mathematical properties of space-time structures such as the spinoral space-time (SST) we introduced in 1996-97 can have strong implications for Quantum Mechanics and even be its real origin. We complete here our recent discussion of the subject by pointing out that: i) Quantum Mechanics corresponds to a natural set of properties of vacuum excitations in the presence of a SST geometry ; ii) the recently observed entanglement at long distances would be a logical property if preons are superluminal (superbradyons), so that superluminal signals and correlations can propagate in vacuum ; iii) in a specific description, the function of space-time associated to the extended internal structure of a spin-1/2 particle at very small distances may be incompatible with a continuous motion at space and time scales where the internal structure of vacuum can be felt. In the dynamics associated to iii), and using the SST approach to space-time, a contradiction can appear between macroscopic and microscopic space-times due to an overlap in the time variable directly related to the fact that a spinorial function takes

  10. Sharing Rare Attitudes Attracts.

    Science.gov (United States)

    Alves, Hans

    2018-04-01

    People like others who share their attitudes. Online dating platforms as well as other social media platforms regularly rely on the social bonding power of their users' shared attitudes. However, little is known about moderating variables. In the present work, I argue that sharing rare compared with sharing common attitudes should evoke stronger interpersonal attraction among people. In five studies, I tested this prediction for the case of shared interests from different domains. I found converging evidence that people's rare compared with their common interests are especially potent to elicit interpersonal attraction. I discuss the current framework's theoretical implications for impression formation and impression management as well as its practical implications for improving online dating services.

  11. Molecular mechanisms regulating flowering time in sweet cherry (Prunus avium L.)

    DEFF Research Database (Denmark)

    Ionescu, Irina Alexandra

    The timing of flowering is a well-researched but at the same time incredibly complex process in angiosperms. Although we are in possession of detailed knowledge on the genetic level of flowering time regulation in the model plant Arabidopsis thaliana, it is often difficult to transfer this knowle......The timing of flowering is a well-researched but at the same time incredibly complex process in angiosperms. Although we are in possession of detailed knowledge on the genetic level of flowering time regulation in the model plant Arabidopsis thaliana, it is often difficult to transfer...... as a result of hydrogen cyanamide treatment: the jasmonate pathway, the hydrogen cyanide pathway and the cytokinin pathway. We further analyzed the levels of cyanogenic glucosides and their derivatives during endodormancy and its release in sweet cherry and almond (Prunus dulcis (Mill.) D. A. Webb). Prunasin...... and its amide coincided with flowering time in both species. Taken together, these results contribute to elucidating parts of the complex network regulating flowering time in perennial plants....

  12. Wigner Distribution Functions and the Representation of Canonical Transformations in Time-Dependent Quantum Mechanics

    Directory of Open Access Journals (Sweden)

    Marcos Moshinsky

    2008-07-01

    Full Text Available For classical canonical transformations, one can, using the Wigner transformation, pass from their representation in Hilbert space to a kernel in phase space. In this paper it will be discussed how the time-dependence of the uncertainties of the corresponding time-dependent quantum problems can be incorporated into this formalism.

  13. Time to Death after Terminal Withdrawal of Mechanical Ventilation: Specific Respiratory and Physiologic Parameters May Inform Physician Predictions.

    Science.gov (United States)

    Long, Ann C; Muni, Sarah; Treece, Patsy D; Engelberg, Ruth A; Nielsen, Elizabeth L; Fitzpatrick, Annette L; Curtis, J Randall

    2015-12-01

    Discussions about withdrawal of life-sustaining therapies often include family members of critically ill patients. These conversations should address essential components of the dying process, including expected time to death after withdrawal. The study objective was to aid physician communication about the dying process by identifying predictors of time to death after terminal withdrawal of mechanical ventilation. We conducted an observational analysis from a single-center, before-after evaluation of an intervention to improve palliative care. We studied 330 patients who died after terminal withdrawal of mechanical ventilation. Predictors included patient demographics, laboratory, respiratory, and physiologic variables, and medication use. The median time to death for the entire cohort was 0.58 hours (interquartile range (IQR) 0.22-2.25 hours) after withdrawal of mechanical ventilation. Using Cox regression, independent predictors of shorter time to death included higher positive end-expiratory pressure (per 1 cm H2O hazard ratio [HR], 1.07; 95% CI 1.04-1.11); higher static pressure (per 1 cm H2O HR, 1.03; 95% CI 1.01-1.04); extubation prior to death (HR, 1.41; 95% CI 1.06-1.86); and presence of diabetes (HR, 1.75; 95% CI 1.25-2.44). Higher noninvasive mean arterial pressure predicted longer time to death (per 1 mmHg HR, 0.98; 95% CI 0.97-0.99). Comorbid illness and key respiratory and physiologic parameters may inform physician predictions of time to death after withdrawal of mechanical ventilation. An understanding of the predictors of time to death may facilitate discussions with family members of dying patients and improve communication about end-of-life care.

  14. On the physical nonexistence of signals going backwards in time, and quantum mechanics

    International Nuclear Information System (INIS)

    Garuccio, A.; Maccarrone, G.D.

    1980-01-01

    With regard to the recent results of new experiments about the EPR-paradox, which seem to disagree with Bell inequality and appear to confirm quantum mechanics, some theoretical interpretations have been proposed. In this letter, it is shown that the interpretations invoking transmission of signals into the past do not seem to be physically acceptable. The positive role of the ''Reinterpretation Principle'' (for an orthodox reinterpretation of the ''advanced solutions'') is in particular stressed. (author)

  15. Time course of lung inflammatory and fibrogenic responses during protective mechanical ventilation in healthy rats.

    Science.gov (United States)

    Krebs, Joerg; Pelosi, Paolo; Tsagogiorgas, Charalambos; Haas, Jenny; Yard, Benito; Rocco, Patricia R M; Luecke, Thomas

    2011-09-15

    This study aimed to assess pulmonary inflammatory and fibrogenic responses and their impact on lung mechanics and histology in healthy rats submitted to protective mechanical ventilation for different experimental periods. Eighteen Wistar rats were randomized to undergo open lung-mechanical ventilation (OL-MV) for 1, 6 or 12 h. Following a recruitment maneuver, a decremental PEEP trial was performed and PEEP set according to the minimal respiratory system static elastance. Respiratory system, lung, and chest-wall elastance and gas-exchange were maintained throughout the 12 h experimental period. Histological lung injury score remained low at 1 and 6 h, but was higher at 12 h due to overinflation. A moderate inflammatory response was observed with a distinct peak at 6h. Compared to unventilated controls, type I procollagen mRNA expression was decreased at 1 and 12h, while type III procollagen expression decreased throughout the 12h experimental period. In conclusion, OL-MV in healthy rats yielded overinflation after 6 h even though respiratory elastance and gas-exchange were preserved for up to 12 h. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Experiment study on failure mechanism of Bai Huichang landslide and analysis on time effect of deformation

    Energy Technology Data Exchange (ETDEWEB)

    Ronghua, Fu; Baokui, Yao; Yuke, Sun

    1985-01-01

    Bai Huichang landslide is a large scale landslide which is of the character of leveled pushing slide and collapse. To study the failure mechanism of the landslide, to analyse the reasons for failure of the landslide, to evaluate and to predict the stability of the slope, systematic tests of physico-mechanical properties of the clay rock on the sliding surface and analysis of the constituents of the substances are made. Tests on slope models made of photo-elastic material and of blocks are made. The results show that the landslide is a typical one with leveled pushing slide and collapse character, and the main reason for the landslide is the poor physico-mechanical properties and the poor water-stable properties of the clay rock which contain a vast amount of the montmorillonite. The deformation of the slope model is very similar to that of the actual slope. Regression analysis of the observed deformation of the slope indicates that the deformation decays at a rate about 70% each year. It means that the landslide will tend to be stable and no serious landslide will occur which will endanger the safety of Changhangou Colliery. 3 references.

  17. Out of time? - Music, consciousness states and neuropharmacological mechanisms of an altered temporality

    OpenAIRE

    Fachner, Jörg

    2009-01-01

    Drug-induced altered temporality is a well-known effect of cannabis action that is utilised from musicians and music listeners for music appreciation since the early days of jazz. Cannabis has an influence on timing processes at short time scales of hundreds of milliseconds as O’Leary et al (2003) have shown in their tapping studies, proving evidence of an altered cerebellar functioning. This paper will focus on cannabis and its action on timing and aims to discuss selected scientific streams...

  18. An active balance board system with real-time control of stiffness and time-delay to assess mechanisms of postural stability.

    Science.gov (United States)

    Cruise, Denise R; Chagdes, James R; Liddy, Joshua J; Rietdyk, Shirley; Haddad, Jeffrey M; Zelaznik, Howard N; Raman, Arvind

    2017-07-26

    Increased time-delay in the neuromuscular system caused by neurological disorders, concussions, or advancing age is an important factor contributing to balance loss (Chagdes et al., 2013, 2016a,b). We present the design and fabrication of an active balance board system that allows for a systematic study of stiffness and time-delay induced instabilities in standing posture. Although current commercial balance boards allow for variable stiffness, they do not allow for manipulation of time-delay. Having two controllable parameters can more accurately determine the cause of balance deficiencies, and allows us to induce instabilities even in healthy populations. An inverted pendulum model of human posture on such an active balance board predicts that reduced board rotational stiffness destabilizes upright posture through board tipping, and limit cycle oscillations about the upright position emerge as feedback time-delay is increased. We validate these two mechanisms of instability on the designed balance board, showing that rotational stiffness and board time-delay induced the predicted postural instabilities in healthy, young adults. Although current commercial balance boards utilize control of rotational stiffness, real-time control of both stiffness and time-delay on an active balance board is a novel and innovative manipulation to reveal balance deficiencies and potentially improve individualized balance training by targeting multiple dimensions contributing to standing balance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Multi-rate sensor fusion-based adaptive discrete finite-time synergetic control for flexible-joint mechanical systems

    International Nuclear Information System (INIS)

    Xue Guang-Yue; Ren Xue-Mei; Xia Yuan-Qing

    2013-01-01

    This paper proposes an adaptive discrete finite-time synergetic control (ADFTSC) scheme based on a multi-rate sensor fusion estimator for flexible-joint mechanical systems in the presence of unmeasured states and dynamic uncertainties. Multi-rate sensors are employed to observe the system states which cannot be directly obtained by encoders due to the existence of joint flexibilities. By using an extended Kalman filter (EKF), the finite-time synergetic controller is designed based on a sensor fusion estimator which estimates states and parameters of the mechanical system with multi-rate measurements. The proposed controller can guarantee the finite-time convergence of tracking errors by the theoretical derivation. Simulation and experimental studies are included to validate the effectiveness of the proposed approach. (general)

  20. Influence of time and pressure of forming a pattern on mechanical properties

    Directory of Open Access Journals (Sweden)

    T. Pacyniak

    2011-07-01

    Full Text Available In this paper, the technology of forming patterns on a research station equipped with an autoclave A-600 of Polish company GROM is presented. This study was conducted to determine the influence of pressure and time of forming a pattern on the bending strength. Analysis of the results confirmed that bending strength increases with increasing the pressure. The time of forming a pattern has a similar effect.

  1. Preliminary research on time degradation of mechanical characteristics of concretes used in nuclear power plant buildings

    International Nuclear Information System (INIS)

    Ciornei, R.

    1991-01-01

    To provide severe safety rules governing the operation of nuclear power plants, reinforced and concrete elements and structures should preserve the quality and time-constant parameters throughout the life-time of the buildings. Some important design parameters are concrete strength and elasticity modulus. Preliminary research on concrete specimens made in laboratory whose strength and static and dynamic elasticity modulus have been determined after an ageing test, has aimed at nuclear power design and building. (author)

  2. Therapeutic time window and underlying therapeutic mechanism of breviscapine injection against cerebral ischemia/reperfusion injury in rats.

    Science.gov (United States)

    Guo, Chao; Zhu, Yanrong; Weng, Yan; Wang, Shiquan; Guan, Yue; Wei, Guo; Yin, Ying; Xi, Miaomaio; Wen, Aidong

    2014-01-01

    Breviscapine injection is a Chinese herbal medicine standardized product extracted from Erigeron breviscapus (Vant.) Hand.-Mazz. It has been widely used for treating cardiovascular and cerebrovascular diseases. However, the therapeutic time window and the action mechanism of breviscapine are still unclear. The present study was designed to investigate the therapeutic time window and underlying therapeutic mechanism of breviscapine injection against cerebral ischemic/reperfusion injury. Sprague-Dawley rats were subjected to middle cerebral artery occlusion for 2h followed by 24h of reperfusion. Experiment part 1 was used to investigate the therapeutic time window of breviscapine. Rats were injected intravenously with 50mg/kg breviscapine at different time-points of reperfusion. After 24h of reperfusion, neurologic score, infarct volume, brain water content and serum level of neuron specific enolase (NSE) were measured in a masked fashion. Part 2 was used to explore the therapeutic mechanism of breviscapine. 4-Hydroxy-2-nonenal (4-HNE), 8-hydroxyl-2'- deoxyguanosine (8-OHdG) and the antioxidant capacity of ischemia cortex were measured by ELISA and ferric-reducing antioxidant power (FRAP) assay, respectively. Immunofluorescence and western blot analysis were used to analyze the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). Part 1: breviscapine injection significantly ameliorated neurologic deficit, reduced infarct volume and water content, and suppressed the levels of NSE in a time-dependent manner. Part 2: breviscapine inhibited the increased levels of 4-HNE and 8-OHdG, and enhanced the antioxidant capacity of cortex tissue. Moreover, breviscapine obviously raised the expression of Nrf2 and HO-1 proteins after 24h of reperfusion. The therapeutic time window of breviscapine injection for cerebral ischemia/reperfusion injury seemed to be within 5h after reperfusion. By up-regulating the expression of Nrf2/HO-1 pathway

  3. The Cross-Cultural Knowledge Sharing Challenge

    DEFF Research Database (Denmark)

    Persson, John Stouby

    2013-01-01

    Cross-cultural offshoring in software development challenges effective knowledge sharing. While research has suggested temporarily co-locating participants to address this challenge, few studies are available on what knowledge sharing practices emerge over time when co-locating cross-cultural sof...

  4. Job Sharing: Is It for You?

    Science.gov (United States)

    Schumann, Linda

    1994-01-01

    A teacher of deaf children describes her experience with job sharing at both the intermediate grade and preschool levels. The important role played by the full-time teacher's aide in providing continuity as well as the importance of communication are emphasized. Guidelines and answers to common questions regarding job sharing are offered. (DB)

  5. Job Sharing for the 80's.

    Science.gov (United States)

    Notowitz, Carol

    1982-01-01

    Discusses the advantages and disadvantages of job-sharing as an alternative to part-time employment in libraries and describes a job-sharing experiment at the Parson Branch of the Public Library of Columbus and Franklin County. Six references are included. (CHC)

  6. Job Sharing: Is It in Your Future?

    Science.gov (United States)

    Russell, Thyra K.

    This paper reports the results of a survey of 1,277 libraries in Illinois which investigated the status of job sharing in armed forces, college and university, community college, government, law, medical, public, religious, and special libraries and library systems. Job sharing is described as the division of one full-time job between two or more…

  7. Chimpanzees share forbidden fruit.

    Directory of Open Access Journals (Sweden)

    Kimberley J Hockings

    2007-09-01

    Full Text Available The sharing of wild plant foods is infrequent in chimpanzees, but in chimpanzee communities that engage in hunting, meat is frequently used as a 'social tool' for nurturing alliances and social bonds. Here we report the only recorded example of regular sharing of plant foods by unrelated, non-provisioned wild chimpanzees, and the contexts in which these sharing behaviours occur. From direct observations, adult chimpanzees at Bossou (Republic of Guinea, West Africa very rarely transferred wild plant foods. In contrast, they shared cultivated plant foods much more frequently (58 out of 59 food sharing events. Sharing primarily consists of adult males allowing reproductively cycling females to take food that they possess. We propose that hypotheses focussing on 'food-for-sex and -grooming' and 'showing-off' strategies plausibly account for observed sharing behaviours. A changing human-dominated landscape presents chimpanzees with fresh challenges, and our observations suggest that crop-raiding provides adult male chimpanzees at Bossou with highly desirable food commodities that may be traded for other currencies.

  8. Biocompatible nanocrystalline natural bonelike carbonated hydroxyapatite synthesized by mechanical alloying in a record minimum time

    Energy Technology Data Exchange (ETDEWEB)

    Lala, S. [Materials Science Division, Department of Physics, The University of Burdwan, Golapbag, Burdwan-713104, West Bengal (India); Brahmachari, S.; Das, P.K. [Department of Biological Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700 032 (India); Das, D. [UGC-DAE Consortium for Scientific Research, Kolkata-700098 (India); Kar, T. [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032 (India); Pradhan, S.K., E-mail: skp_bu@yahoo.com [Materials Science Division, Department of Physics, The University of Burdwan, Golapbag, Burdwan-713104, West Bengal (India)

    2014-09-01

    Single phase nanocrystalline biocompatible A-type carbonated hydroxyapatite (A-cHAp) powder has been synthesized by mechanical alloying the stoichiometric mixture of CaCO{sub 3} and CaHPO{sub 4}.2H{sub 2}O powders in open air at room temperature within 2 h of milling. The A-type carbonation in HAp is confirmed by FTIR analysis. Structural and microstructure parameters of as-milled powders are obtained from both Rietveld's powder structure refinement analysis and transmission electron microscopy. Size and lattice strain of nanocrystalline HAp particles are found to be anisotropic in nature. Mechanical alloying causes amorphization of a part of crystalline A-cHAp which is analogous to native bone mineral. Some primary bond lengths of as-milled samples are critically measured. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay test reveals high percentage of cell viability and hence confirms the biocompatibility of the sample. The overall results indicate that the processed A-cHAp has a chemical composition very close to that of biological apatite. - Graphical abstract: Biocompatible A-Type Carbonated Hydroxyapatite (A-cHAp) has been synthesized by mechanical alloying in polycrystalline form within 2 h of milling. The shape and position of CO channel have been shown. - Highlights: • A-cHAp phase is completed within 2 h of milling. • FTIR analysis confirms A-type carbonation in HAp. • Amorphization of a part of crystalline A-cHAp. • Particle size and strain are anaisotropic in nature. • High cell viability under MTT assay.

  9. Integrated automated nanomanipulation and real-time cellular surface imaging for mechanical properties characterization

    Science.gov (United States)

    Eslami, Sohrab; Zareian, Ramin; Jalili, Nader

    2012-10-01

    Surface microscopy of individual biological cells is essential for determining the patterns of cell migration to study the tumor formation or metastasis. This paper presents a correlated and effective theoretical and experimental technique to automatically address the biophysical and mechanical properties and acquire live images of biological cells which are of interest in studying cancer. In the theoretical part, a distributed-parameters model as the comprehensive representation of the microcantilever is presented along with a model of the contact force as a function of the indentation depth and mechanical properties of the biological sample. Analysis of the transfer function of the whole system in the frequency domain is carried out to characterize the stiffness and damping coefficients of the sample. In the experimental section, unlike the conventional atomic force microscope techniques basically using the laser for determining the deflection of microcantilever's tip, a piezoresistive microcantilever serving as a force sensor is implemented to produce the appropriate voltage and measure the deflection of the microcantilever. A micromanipulator robotic system is integrated with the MATLAB® and programmed in such a way to automatically control the microcantilever mounted on the tip of the micromanipulator to achieve the topography of biological samples including the human corneal cells. For this purpose, the human primary corneal fibroblasts are extracted and adhered on a sterilized culture dish and prepared to attain their topographical image. The proposed methodology herein allows an approach to obtain 2D quality images of cells being comparatively cost effective and extendable to obtain 3D images of individual cells. The characterized mechanical properties of the human corneal cell are furthermore established by comparing and validating the phase shift of the theoretical and experimental results of the frequency response.

  10. Physical nonexistence of signals going backwards in time, and quantum mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Garuccio, A. (Bari Univ. (Italy). Ist. di Fisica; Istituto Nazionale di Fisica Nucleare, Bari (Italy)); Maccarrone, G.D. (Catania Univ. (Italy). Scuola di Specializzazione in Fisica); Recami, E. (Catania Univ. (Italy). Ist. di Fisica; Istituto Nazionale di Fisica Nucleare, Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Catania (Italy))

    1980-01-12

    With regard to the recent results of new experiments about the EPR-paradox, which seem to disagree with Bell inequality and appear to confirm quantum mechanics, some theoretical interpretations have been proposed. In this letter, it is shown that the interpretations invoking transmission of signals into the past do not seem to be physically acceptable. The positive role of the ''Reinterpretation Principle'' (for an orthodox reinterpretation of the ''advanced solutions'') is in particular stressed.

  11. The right time to learn: mechanisms and optimization of spaced learning

    Science.gov (United States)

    Smolen, Paul; Zhang, Yili; Byrne, John H.

    2016-01-01

    For many types of learning, spaced training, which involves repeated long inter-trial intervals, leads to more robust memory formation than does massed training, which involves short or no intervals. Several cognitive theories have been proposed to explain this superiority, but only recently have data begun to delineate the underlying cellular and molecular mechanisms of spaced training, and we review these theories and data here. Computational models of the implicated signalling cascades have predicted that spaced training with irregular inter-trial intervals can enhance learning. This strategy of using models to predict optimal spaced training protocols, combined with pharmacotherapy, suggests novel ways to rescue impaired synaptic plasticity and learning. PMID:26806627

  12. Had We But World Enough, and Time... But We Don't!: Justifying the Thermodynamic and Infinite-Time Limits in Statistical Mechanics

    Science.gov (United States)

    Palacios, Patricia

    2018-05-01

    In this paper, I compare the use of the thermodynamic limit in the theory of phase transitions with the infinite-time limit in the explanation of equilibrium statistical mechanics. In the case of phase transitions, I will argue that the thermodynamic limit can be justified pragmatically since the limit behavior (i) also arises before we get to the limit and (ii) for values of N that are physically significant. However, I will contend that the justification of the infinite-time limit is less straightforward. In fact, I will point out that even in cases where one can recover the limit behavior for finite t, i.e. before we get to the limit, one cannot recover this behavior for realistic time scales. I will claim that this leads us to reconsider the role that the rate of convergence plays in the justification of infinite limits and calls for a revision of the so-called Butterfield's principle.

  13. Had We But World Enough, and Time... But We Don't!: Justifying the Thermodynamic and Infinite-Time Limits in Statistical Mechanics

    Science.gov (United States)

    Palacios, Patricia

    2018-04-01

    In this paper, I compare the use of the thermodynamic limit in the theory of phase transitions with the infinite-time limit in the explanation of equilibrium statistical mechanics. In the case of phase transitions, I will argue that the thermodynamic limit can be justified pragmatically since the limit behavior (i) also arises before we get to the limit and (ii) for values of N that are physically significant. However, I will contend that the justification of the infinite-time limit is less straightforward. In fact, I will point out that even in cases where one can recover the limit behavior for finite t, i.e. before we get to the limit, one cannot recover this behavior for realistic time scales. I will claim that this leads us to reconsider the role that the rate of convergence plays in the justification of infinite limits and calls for a revision of the so-called Butterfield's principle.

  14. To share or not to share? Expected pros and cons of data sharing in radiological research.

    Science.gov (United States)

    Sardanelli, Francesco; Alì, Marco; Hunink, Myriam G; Houssami, Nehmat; Sconfienza, Luca M; Di Leo, Giovanni

    2018-06-01

    The aims of this paper are to illustrate the trend towards data sharing, i.e. the regulated availability of the original patient-level data obtained during a study, and to discuss the expected advantages (pros) and disadvantages (cons) of data sharing in radiological research. Expected pros include the potential for verification of original results with alternative or supplementary analyses (including estimation of reproducibility), advancement of knowledge by providing new results by testing new hypotheses (not explored by the original authors) on pre-existing databases, larger scale analyses based on individual-patient data, enhanced multidisciplinary cooperation, reduced publication of false studies, improved clinical practice, and reduced cost and time for clinical research. Expected cons are outlined as the risk that the original authors could not exploit the entire potential of the data they obtained, possible failures in patients' privacy protection, technical barriers such as the lack of standard formats, and possible data misinterpretation. Finally, open issues regarding data ownership, the role of individual patients, advocacy groups and funding institutions in decision making about sharing of data and images are discussed. • Regulated availability of patient-level data of published clinical studies (data-sharing) is expected. • Expected benefits include verification/advancement of knowledge, reduced cost/time of research, clinical improvement. • Potential drawbacks include faults in patients' identity protection and data misinterpretation.

  15. Sharing the dance -

    DEFF Research Database (Denmark)

    He, Jing; Ravn, Susanne

    2018-01-01

    In his recent works on daily face-to-face encounters, Zahavi claims that the phenomenon of sharing involves reciprocity. Following Zahavi’s line of thought, we wonder what exactly reciprocity amounts to and how the shared experience emerges from the dynamic process of interaction. By turning...... to the highly specialized field of elite sports dance, we aim at exploring the way in which reciprocity unfolds in intensive deliberate practices of movement. In our analysis, we specifically argue that the ongoing dynamics of two separate flows of movement constitute a shared experience of dancing together...

  16. Report endorses data sharing

    Science.gov (United States)

    The potential benefits of sharing data so outweigh its costs that investigators should be required to include plans for sharing data as part of their grant proposals, according to recommendations issued recently by the Committee on National Statistics (CNSTAT) of the National Research Council (NRC).In their report Sharing Research Data, CNSTAT also recommended that “Journals should give more emphasis to reports of secondary analyses and to replications,” provided that the original collections of data receive full credit. In addition, “Journal editors should require authors to provide access to data during the peer review process.”

  17. Unification & sharing in timed automata verification

    DEFF Research Database (Denmark)

    David, Alexandre; Behrmann, Gerd; Larsen, Kim Guldstrand

    2003-01-01

    We present the design of the model-checking engine and internal data structures for the next generation of UPPAAL. The design is based on a pipeline architecture where each stage represents one independent operation in the verification algorithms. The architecture is based on essentially one shar...

  18. Photophysics and Photochemistry of Canonical Nucleobases’ Thioanalogs: From Quantum Mechanical Studies to Time Resolved Experiments

    Directory of Open Access Journals (Sweden)

    Serra Arslancan

    2017-06-01

    Full Text Available Interest in understanding the photophysics and photochemistry of thiated nucleobases has been awakened because of their possible involvement in primordial RNA or their potential use as photosensitizers in medicinal chemistry. The interpretation of the photodynamics of these systems, conditioned by their intricate potential energy surfaces, requires the powerful interplay between experimental measurements and state of the art molecular simulations. In this review, we provide an overview on the photophysics of natural nucleobases’ thioanalogs, which covers the last 30 years and both experimental and computational contributions. For all the canonical nucleobase’s thioanalogs, we have compiled the main steady state absorption and emission features and their interpretation in terms of theoretical calculations. Then, we revise the main topographical features, including stationary points and interstate crossings, of their potential energy surfaces based on quantum mechanical calculations and we conclude, by combining the outcome of different spectroscopic techniques and molecular dynamics simulations, with the mechanism by which these nucleobase analogs populate their triplet excited states, which are at the origin of their photosensitizing properties.

  19. Creep rupture behavior of polypropylene suture material and its applications as a time-release mechanism

    International Nuclear Information System (INIS)

    Kusy, R.P.; Whitley, J.Q.

    1983-01-01

    The controlled failure of polypropylene (PP) sutures is studied via creep rupture tests. From plots of log time (tB) vs. stress (sigma), linear relationships are generated over the failure times of 1-1000 h. Results show that as a function of stress, the time dependence varies with irradiation dose (15, 20, 25, and 50 Mrad), irradiation atmosphere (air and vacuum), suture diameter (7-0, 6-0, 5-0, and 4-0), and test temperature (26 and 37 degrees C). For a given stress, the time to failure is least for the greatest dose in the presence of air and at the highest temperature. When suture loops are wrapped around a small wire sheave, however, failure occurs in the largest suture as much as two decades sooner than the smallest suture studied. Within the limitations stated herein, they are independent of test method, loop diameter, aging, and humidity. Consequently, after irradiation in vacuum and postirradiation heat treatment, the processed material may be stored at room temperature for at least 1 month. Such materials are advocated when the time release of a dental or medical device is required, for example, in the self-activating cleft palate appliance

  20. Effect of deposition time of sputtering Ag-Cu thin film on mechanical and antimicrobial properties

    Science.gov (United States)

    Purniawan, A.; Hermastuti, R.; Purwaningsih, H.; Atmono, T. M.

    2018-04-01

    Metallic implants are important components in biomedical treatment. However, post-surgery infection often occurs after installation of implant. The infections are usually treated by antibiotics, but it still causes several secondary problems. As a prevention treatment, the surgical instruments and implants must be in a sterile condition. This action is still not optimal too because the material still can attract the bacteria. From material science point of view, it can be anticipated by developing a type of material which has antibacterial properties or called antimicrobial material. Silver (Ag) and Copper (Cu) have antimicrobial properties to prevent the infection. In this research, the influence of deposition time of Ag-Cu thin film deposition process as antimicrobial material with Physical Vapor Deposition (PVD) RF Sputtering method was analyzed. Deposition time used were for 10, 15 and 20 minutes in Argon gas pressure around 3 x 10-2 mbar in during deposition process. The morphology and surface roughness of Ag-Cu thin film were characterized using SEM and AFM. Based on the results, the deposition time influences the quality morphology that the thin films have good homogeneity and complete structure for longer deposition time. In addition, from roughness measurement results show that increase deposition time decrease the roughness of thin film. Antimicrobial performance was analyzed using Kirby Bauer Test. The results show that all of sample have good antimicrobial inhibition. Adhesion quality was evaluated using Rockwell C Indentation Test. However, the results indicate that the Ag-Cu thin film has low adhesion strength.