Mimicking Nonequilibrium Steady States with Time-Periodic Driving (Open Source)

Science.gov (United States)

2016-05-18

construction does not require the solution of any differential equations , only linear algebraic equations . By contrast, a mapping in the opposite...set of algebraic linear equations . The mapping between NESS and SP presented above was not intended as a set of operational instructions for... differential equations with time-periodic parameters. Typically, this can only be done numerically. In some applications, transition rates are constrained by

Periodic Operation of Three-Phase Catalytic Reactors

Czech Academy of Sciences Publication Activity Database

Silveston, P.T.; Hanika, Jiří

2005-01-01

Roč. 82, č. 6 (2005), s. 1105-1142 ISSN 0008-4034 Institutional research plan: CEZ:AV0Z4072921 Keywords : three-phase reactors * trickle bed * periodic operation Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.574, year: 2005

Algorithm for determining two-periodic steady-states in AC machines directly in time domain

Directory of Open Access Journals (Sweden)

Sobczyk Tadeusz J.

2016-09-01

Full Text Available This paper describes an algorithm for finding steady states in AC machines for the cases of their two-periodic nature. The algorithm enables to specify the steady-state solution identified directly in time domain despite of the fact that two-periodic waveforms are not repeated in any finite time interval. The basis for such an algorithm is a discrete differential operator that specifies the temporary values of the derivative of the two-periodic function in the selected set of points on the basis of the values of that function in the same set of points. It allows to develop algebraic equations defining the steady state solution reached in a chosen point set for the nonlinear differential equations describing the AC machines when electrical and mechanical equations should be solved together. That set of those values allows determining the steady state solution at any time instant up to infinity. The algorithm described in this paper is competitive with respect to the one known in literature an approach based on the harmonic balance method operated in frequency domain.

Typical Periods for Two-Stage Synthesis by Time-Series Aggregation with Bounded Error in Objective Function

Energy Technology Data Exchange (ETDEWEB)

Bahl, Björn; Söhler, Theo; Hennen, Maike; Bardow, André, E-mail: andre.bardow@ltt.rwth-aachen.de [Institute of Technical Thermodynamics, RWTH Aachen University, Aachen (Germany)

2018-01-08

Two-stage synthesis problems simultaneously consider here-and-now decisions (e.g., optimal investment) and wait-and-see decisions (e.g., optimal operation). The optimal synthesis of energy systems reveals such a two-stage character. The synthesis of energy systems involves multiple large time series such as energy demands and energy prices. Since problem size increases with the size of the time series, synthesis of energy systems leads to complex optimization problems. To reduce the problem size without loosing solution quality, we propose a method for time-series aggregation to identify typical periods. Typical periods retain the chronology of time steps, which enables modeling of energy systems, e.g., with storage units or start-up cost. The aim of the proposed method is to obtain few typical periods with few time steps per period, while accurately representing the objective function of the full time series, e.g., cost. Thus, we determine the error of time-series aggregation as the cost difference between operating the optimal design for the aggregated time series and for the full time series. Thereby, we rigorously bound the maximum performance loss of the optimal energy system design. In an initial step, the proposed method identifies the best length of typical periods by autocorrelation analysis. Subsequently, an adaptive procedure determines aggregated typical periods employing the clustering algorithm k-medoids, which groups similar periods into clusters and selects one representative period per cluster. Moreover, the number of time steps per period is aggregated by a novel clustering algorithm maintaining chronology of the time steps in the periods. The method is iteratively repeated until the error falls below a threshold value. A case study based on a real-world synthesis problem of an energy system shows that time-series aggregation from 8,760 time steps to 2 typical periods with each 2 time steps results in an error smaller than the optimality gap of

Operation aid device upon periodical inspection of nuclear power plant

International Nuclear Information System (INIS)

Fukusaka, Ryoji.

1997-01-01

The present invention provides an operation aid device upon periodical inspection of a nuclear power plant, capable of controlling a plurality of control rods safely at good operation efficiency while maintaining subcritical state. Namely, a fuel exchange computer controls an operation for exchanging fuel assemblies upon periodical inspection. An operation aiding computer aids the exchanging operation of fuel assemblies. A control rod position monitoring device allows withdrawal of one control rod under the condition of establishment of entire control rod insertion signal upon operation of exchanging fuel assemblies. Whether all of the four fuel assemblies around one control rod have been entirely taken out or not is judged based on information on the fuel assembly exchanging operation. When conditions for the judgement for operation aiding computer are established, the all insertion signals for the entire control rods as the condition for the withdrawal of the control rods are bypassed, and operation enable signals for plurality control rods are outputted to a control rod manual operation device. (I.S.)

Catalytic performance improvement of styrene hydrogenation in trickle bed reactor by using periodic operation

International Nuclear Information System (INIS)

Wongkia, Atittahn; Praserthdam, Piyasan; Assabumrungrat, Suttichai; Suriye, Kongkiat; Nonkhamwong, Anuwat

2013-01-01

We investigated the catalytic performance improvement of styrene hydrogenation in a trickle bed reactor by using periodic operation. The effects of cycle period and split on relative conversion, which is defined as styrene conversion obtained from periodic operation over that from steady state operation, were examined at various operating conditions including gas and average liquid flow rates, pressure and temperature. The experimental results reveal that both cycle period and split have strong influence on the catalytic performance. The fast mode (short cycle period) is a favorable condition. The improvement by the periodic operation becomes less pronounced for operations at high average liquid flow rate, pressure and temperature. From this study, a maximum improvement of styrene conversion of 18% is observed

Catalytic performance improvement of styrene hydrogenation in trickle bed reactor by using periodic operation

Energy Technology Data Exchange (ETDEWEB)

Wongkia, Atittahn; Praserthdam, Piyasan; Assabumrungrat, Suttichai [Chulalongkorn University, Bangkok (Thailand); Suriye, Kongkiat; Nonkhamwong, Anuwat [SCG Chemicals Co. Ltd., Bangkok (Thailand)

2013-03-15

We investigated the catalytic performance improvement of styrene hydrogenation in a trickle bed reactor by using periodic operation. The effects of cycle period and split on relative conversion, which is defined as styrene conversion obtained from periodic operation over that from steady state operation, were examined at various operating conditions including gas and average liquid flow rates, pressure and temperature. The experimental results reveal that both cycle period and split have strong influence on the catalytic performance. The fast mode (short cycle period) is a favorable condition. The improvement by the periodic operation becomes less pronounced for operations at high average liquid flow rate, pressure and temperature. From this study, a maximum improvement of styrene conversion of 18% is observed.

Phased mission modelling of systems with maintenance-free operating periods using simulated Petri nets

Energy Technology Data Exchange (ETDEWEB)

Chew, S.P.; Dunnett, S.J. [Department of Aeronautical and Automotive Engineering, Loughborough University, Loughborough, Leics (United Kingdom); Andrews, J.D. [Department of Aeronautical and Automotive Engineering, Loughborough University, Loughborough, Leics (United Kingdom)], E-mail: j.d.andrews@lboro.ac.uk

2008-07-15

A common scenario in engineering is that of a system which operates throughout several sequential and distinct periods of time, during which the modes and consequences of failure differ from one another. This type of operation is known as a phased mission, and for the mission to be a success the system must successfully operate throughout all of the phases. Examples include a rocket launch and an aeroplane flight. Component or sub-system failures may occur at any time during the mission, yet not affect the system performance until the phase in which their condition is critical. This may mean that the transition from one phase to the next is a critical event that leads to phase and mission failure, with the root cause being a component failure in a previous phase. A series of phased missions with no maintenance may be considered as a maintenance-free operating period (MFOP). This paper describes the use of a Petri net (PN) to model the reliability of the MFOP and phased missions scenario. The model uses Monte-Carlo simulation to obtain its results, and due to the modelling power of PNs, can consider complexities such as component failure rate interdependencies and mission abandonment. The model operates three different types of PN which interact to provide the overall system reliability modelling. The model is demonstrated and validated by considering two simple examples that can be solved analytically.

Phased mission modelling of systems with maintenance-free operating periods using simulated Petri nets

International Nuclear Information System (INIS)

Chew, S.P.; Dunnett, S.J.; Andrews, J.D.

2008-01-01

A common scenario in engineering is that of a system which operates throughout several sequential and distinct periods of time, during which the modes and consequences of failure differ from one another. This type of operation is known as a phased mission, and for the mission to be a success the system must successfully operate throughout all of the phases. Examples include a rocket launch and an aeroplane flight. Component or sub-system failures may occur at any time during the mission, yet not affect the system performance until the phase in which their condition is critical. This may mean that the transition from one phase to the next is a critical event that leads to phase and mission failure, with the root cause being a component failure in a previous phase. A series of phased missions with no maintenance may be considered as a maintenance-free operating period (MFOP). This paper describes the use of a Petri net (PN) to model the reliability of the MFOP and phased missions scenario. The model uses Monte-Carlo simulation to obtain its results, and due to the modelling power of PNs, can consider complexities such as component failure rate interdependencies and mission abandonment. The model operates three different types of PN which interact to provide the overall system reliability modelling. The model is demonstrated and validated by considering two simple examples that can be solved analytically

Welded repair joints of boiler steels following operation in creep conditions exceeding the design time of operation

Energy Technology Data Exchange (ETDEWEB)

Dobrzanski, J.; Paszkowska, H.; Zielinski, A. [Institute for Ferrous Metallurgy, Gliwice (Poland)

2010-07-01

The assessment of suitability for further operation for materials and welded repair joints of thick-walled main steam pipeline components, made of steel 14MoV63, as well as steam superheater outlet headers made of steel X20CrMoV121 following operation in creep conditions in time periods considerably longer than the specified calculated time of operation. Strength properties, impact strength and transition temperature into brittle condition, as well as structure condition have been evaluated. On the basis of shortened creep tests, the residual life and disposable residual life of materials and welded joints have been determined. Material properties following operation and those of fabricated circumferential welded repair joints have been compared. The condition of examined components and suitability of the fabricated welded repair joints for further operation have been assessed. (orig.)

Formation and removal of dioxins in a MSWI during different operating periods

Energy Technology Data Exchange (ETDEWEB)

Wang, H.C.; Hwang, J.F. [Center for Environmental, Safety, and Health Technology, Industrial Technology Research Institute, Hsin-Chu (Taiwan). Environmental Health and Air Pollution Division; Chang, M.B.; Chi, K.H. [National Central University, Chungli (Taiwan). Graduate Inst. of Environmental Engineering

2004-09-15

There was little literature to report the dioxin emission concentrations and characteristics during start-up and burndown periods. This research aims to establish the databases of dioxin concentrations in the flue gas and evaluate the dioxin removal efficiencies by air pollution control devices (APCDs) at different operating periods (during start-up, normal operating and burn down periods).

The operative treatment of pressure sores in the pelvic region: A 10-year period overview.

Science.gov (United States)

Jósvay, János; Klauber, András; Both, Béla; Kelemen, Péter B; Varga, Zsombor Z; Pesthy, Pál Cs

2015-07-01

Pelvic region pressure sores often develop following spinal cord injury. Surgery is often necessary for long standing, large-sized pressure sores not responding to conservative treatment. Authors analyze their results of a 10-year period, and identify factors contributing to the reduction of the recurrence rate. A total of 119 pressure sores were operated on 98 patients in two institutions during a 10-year period (1 January 2003 to 31 December 2012). The encountered perioperative complications are summarized, and the recurrence rate is analyzed with a patient follow-up questionnaire. We experienced 15 perioperative complications (12.6%). All complications were fully resolved by conservative treatment. Fifty-eight returned patient replies were processed. The average follow-up time after surgery was 5.2 years. The recurrence rate was 5.47%. The strict adherence to surgical indications, full patient compliance, specialized pre- and post-operative patient care, our routinely used preferred surgical method, all contribute to a low post-operative complication rate, long-term flap survival, and an extended recurrence free period.

Periodic flows to chaos in time-delay systems

CERN Document Server

Luo, Albert C J

2017-01-01

This book for the first time examines periodic motions to chaos in time-delay systems, which exist extensively in engineering. For a long time, the stability of time-delay systems at equilibrium has been of great interest from the Lyapunov theory-based methods, where one cannot achieve the ideal results. Thus, time-delay discretization in time-delay systems was used for the stability of these systems. In this volume, Dr. Luo presents an accurate method based on the finite Fourier series to determine periodic motions in nonlinear time-delay systems. The stability and bifurcation of periodic motions are determined by the time-delayed system of coefficients in the Fourier series and the method for nonlinear time-delay systems is equivalent to the Laplace transformation method for linear time-delay systems. Facilitates discovery of analytical solutions of nonlinear time-delay systems; Illustrates bifurcation trees of periodic motions to chaos; Helps readers identify motion complexity and singularity; Explains pro...

Factorizing the time evolution operator

International Nuclear Information System (INIS)

Garcia Quijas, P C; Arevalo Aguilar, L M

2007-01-01

There is a widespread belief in the quantum physical community, and textbooks used to teach quantum mechanics, that it is a difficult task to apply the time evolution operator e itH-hat/h on an initial wavefunction. Because the Hamiltonian operator is, generally, the sum of two operators, then it is not possible to apply the time evolution operator on an initial wavefunction ψ(x, 0), for it implies using terms like (a-hat + b-hat). A possible solution is to factorize the time evolution operator and then apply successively the individual exponential operator on the initial wavefunction. However, the exponential operator does not directly factorize, i.e. e a-hat+b-hat ≠ e a-hat e b-hat . In this study we present a useful procedure for factorizing the time evolution operator when the argument of the exponential is a sum of two operators, which obey specific commutation relations. Then, we apply the exponential operator as an evolution operator for the case of elementary unidimensional potentials, like a particle subject to a constant force and a harmonic oscillator. Also, we discuss an apparent paradox concerning the time evolution operator and non-spreading wave packets addressed previously in the literature

Occupational radiation exposure at the Eurochemic reprocessing plant during normal operation and intervention periods

International Nuclear Information System (INIS)

Osipenco, A.

1980-01-01

The Eurochemic reprocessing plant is a direct-maintenance, demonstration facility. From 1966 to 1974 it has processed about 180 tonnes of natural or low-enriched uranium, mainly as oxide, and about 30 tonnes of alloys of aluminium and highly enriched uranium. In this period, the operation was stopped for the time necessary to build and connect a new unit for the separation and purification of plutonium. As from 1975, all equipment was rinsed in order to put the plant in standby, some particular equipment was dismantled and a campaign of systematic decontamination was started. Simultaneously, the necessary steps were taken for the solidification and conditioning for storage or disposal of the wastes produced during the operation of the plant. The methods used to determine the individual doses due to external or internal irradiation are shortly described, as well as the rules set up for limiting these doses or for authorizing planned exposures. For the period 1966-1978 the paper shows the distribution of yearly individual and collective doses recorded for the permanent staff and for workers occupied for limited times. Correlations are shown between the absorbed doses and the nature of the work (normal operation, intervention, etc.) or the function in the enterprise (operation, maintenance, health physics, etc.). A small number of incidents leading to intakes or doses higher than normal did occur. However, experience has shown that careful planning and close collaboration between operational and health physics staff have resulted in keeping the doses within the authorized limits. (author)

Modeling operators' emergency response time for chemical processing operations.

Science.gov (United States)

Murray, Susan L; Harputlu, Emrah; Mentzer, Ray A; Mannan, M Sam

2014-01-01

Operators have a crucial role during emergencies at a variety of facilities such as chemical processing plants. When an abnormality occurs in the production process, the operator often has limited time to either take corrective actions or evacuate before the situation becomes deadly. It is crucial that system designers and safety professionals can estimate the time required for a response before procedures and facilities are designed and operations are initiated. There are existing industrial engineering techniques to establish time standards for tasks performed at a normal working pace. However, it is reasonable to expect the time required to take action in emergency situations will be different than working at a normal production pace. It is possible that in an emergency, operators will act faster compared to a normal pace. It would be useful for system designers to be able to establish a time range for operators' response times for emergency situations. This article develops a modeling approach to estimate the time standard range for operators taking corrective actions or following evacuation procedures in emergency situations. This will aid engineers and managers in establishing time requirements for operators in emergency situations. The methodology used for this study combines a well-established industrial engineering technique for determining time requirements (predetermined time standard system) and adjustment coefficients for emergency situations developed by the authors. Numerous videos of workers performing well-established tasks at a maximum pace were studied. As an example, one of the tasks analyzed was pit crew workers changing tires as quickly as they could during a race. The operations in these videos were decomposed into basic, fundamental motions (such as walking, reaching for a tool, and bending over) by studying the videos frame by frame. A comparison analysis was then performed between the emergency pace and the normal working pace operations

The Bessel-Struve intertwining operator on ℂ and mean-periodic functions

Directory of Open Access Journals (Sweden)

A. Gasmi

2004-01-01

Full Text Available We give a description of all transmutation operators from the Bessel-Struve operator to the second-derivative operator. Next we define and characterize the mean-periodic functions on the space ℋ of entire functions and we characterize the continuous linear mappings from ℋ into itself which commute with Bessel-Struve operator.

7 CFR 1.603 - How are time periods computed?

Science.gov (United States)

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false How are time periods computed? 1.603 Section 1.603... Licenses General Provisions § 1.603 How are time periods computed? (a) General. Time periods are computed as follows: (1) The day of the act or event from which the period begins to run is not included. (2...

Extending an open-source real-time operating system with hierarchical scheduling

NARCIS (Netherlands)

Holenderski, M.J.; Cools, W.A.; Bril, R.J.; Lukkien, J.J.

2010-01-01

Hierarchical scheduling frameworks (HSFs) have been devised to support the integration of independently developed and analyzed subsystems. This paper presents an efficient, modular and extendible design for enhancing a real-time operating system with periodic tasks, two-level fixed-priority HSF

Prolonged operative time increases infection rate in tibial plateau fractures.

Science.gov (United States)

Colman, Matthew; Wright, Adam; Gruen, Gary; Siska, Peter; Pape, Hans-Christoph; Tarkin, Ivan

2013-02-01

Fractures of the tibial plateau present a treatment challenge and are susceptible to both prolonged operative times and high postoperative infection rates. For those fractures treated with open plating, we sought to identify the relationship between surgical site infection and prolonged operative time as well as to identify other surgical risk factors. We performed a retrospective controlled analysis of 309 consecutive unicondylar and bicondylar tibial plateau fractures treated with open plate osteosynthesis at our institution's level I trauma centre during a recent 5-year period. We recorded operative times, injury characteristics, surgical treatment, and need for operative debridement due to infection. Operative times of infected cases were compared to uncomplicated surgical cases. Multivariable logistic regression analysis was performed to identify independent risk factors for postoperative infection. Mean operative time in the infection group was 2.8h vs. 2.2h in the non-infected group (p=0.005). 15 fractures (4.9%) underwent four compartment fasciotomies as part of their treatment, with a significantly higher infection rate than those not undergoing fasciotomy (26.7% vs. 6.8%, p=0.01). Open fracture grade was also significantly related to infection rate (closed fractures: 5.3%, grade 1: 14.3%, grade 2: 40%, grade 3: 50%, pinfection rates (13.9% vs. 8.7%, p=0.36). Multivariable logistic regression analysis of the entire study group identified longer operative times (OR 1.78, p=0.013) and open fractures (OR 7.02, psite infection. Operative times approaching 3h and open fractures are related to an increased overall risk for surgical site infection after open plating of the tibial plateau. Dual incision approaches with bicolumnar plating do not appear to expose the patient to increased risk compared to single incision approaches. Copyright © 2012 Elsevier Ltd. All rights reserved.

Algebra of 2D periodic operators with local and perpendicular defects

DEFF Research Database (Denmark)

Kutsenko, Anton

2016-01-01

We show that 2D periodic operators with local and perpendicular defects form an algebra. We provide an algorithm for finding spectrum for such operators. While the continuous spectral components can be computed by simple algebraic operations on some matrix-valued functions and a few number...

50 CFR 221.3 - How are time periods computed?

Science.gov (United States)

2010-10-01

... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false How are time periods computed? 221.3... Provisions § 221.3 How are time periods computed? (a) General. Time periods are computed as follows: (1) The day of the act or event from which the period begins to run is not included. (2) The last day of the...

Off-Policy Reinforcement Learning: Optimal Operational Control for Two-Time-Scale Industrial Processes.

Science.gov (United States)

Li, Jinna; Kiumarsi, Bahare; Chai, Tianyou; Lewis, Frank L; Fan, Jialu

2017-12-01

Industrial flow lines are composed of unit processes operating on a fast time scale and performance measurements known as operational indices measured at a slower time scale. This paper presents a model-free optimal solution to a class of two time-scale industrial processes using off-policy reinforcement learning (RL). First, the lower-layer unit process control loop with a fast sampling period and the upper-layer operational index dynamics at a slow time scale are modeled. Second, a general optimal operational control problem is formulated to optimally prescribe the set-points for the unit industrial process. Then, a zero-sum game off-policy RL algorithm is developed to find the optimal set-points by using data measured in real-time. Finally, a simulation experiment is employed for an industrial flotation process to show the effectiveness of the proposed method.

40 CFR 63.130 - Transfer operations provisions-periodic recordkeeping and reporting.

Science.gov (United States)

2010-07-01

...: A check off on a log sheet; a list of DOT serial numbers or Method 27 data; or a position... in the Notification of Compliance Status or operating permit. (2) Reports of the duration of periods... of Compliance Status or operating permit. (e) The owner or operator of a Group 1 transfer rack shall...

ILK statement on determining operation periods for nuclear power plants in Germany; ILK-Stellungnahme zur Festlegung von Betriebszeiten fuer Kernkfraftwerke in Deutschland

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-09-15

The question of how long nuclear power plants (NPPs) can be safely operated while maintaining a high safety standard played an important role in the worldwide expert discussion in recent years. Far-reaching agreement exists on which reviews and measures to undertake in order to safely operate such plants over longer time periods. In most countries operating licenses for NPPs are not limited in time; this is also the case for Germany. However, the authorization for power operation expires if the plant has used up its approved electricity generation quota. This quota corresponds to a value established in the Atomic Energy Act (AtG) for the individual unit that is based on an operating time of 32 years. On the basis of operating experiences gathered with plants currently in operation and also due to available research findings, the ILK believes that there are no safetyrelated reasons for limiting the operating time of nuclear power plants a priori. The ILK notes that the German NPPs have a high safety standard that is constantly monitored by the regulatory authority. Periodic safety reviews (PSRs), which are performed every ten years, are part of this process. The ILK also takes the view, however, that in the case of very long operating periods, it makes sense to make the continued operation depend on a renewed evaluation (of the plant). This requires demonstrating that the plant displays a level of safety that corresponds to the requirements for the future operating period. The ILK recommends the following approach: - The limitation of production quotas currently laid down in the German Atomic Energy Act should be lifted; - In addition to maintaining the current safety standard, licensees should examine improvement measures for the further reduction of the residual risk and, where appropriate, apply these. The effectiveness of the PSR in its current form should be assessed and the guidelines for their application should be updated, if necessary; - After an operating

On periodic orbits in discrete-time cascade systems

Directory of Open Access Journals (Sweden)

Huimin Li

2006-01-01

Full Text Available We present some results on existence, minimum period, number of periodic orbits, and stability of periodic orbits in discrete-time cascade systems. Some examples are presented to illustrate these results.

Fabrication of fiber optic long period gratings operating at the phase matching turning point using an amplitude mask

Science.gov (United States)

Hromadka, J.; Correia, R.; Korposh, S.

2016-05-01

A fast method for the fabrication of the long period gratings (LPG) optical fibres operating at or near the phase matching turning point (PMTP) with the period of 109.0, 109.5 and 110.0 μm based on an amplitude mask writing system is described. The proposed system allows fabricating 3 cm long LPG sensors operating at PMPT within 20 min that is approximately 8 times faster than point-by-point approach. The reproducibility of the fabrication process was thoroughly studied. The response of the fabricated LPGs to the external change of the refractive index was investigated using water and methanol.

Essential spectra of difference operators on Zn-periodic graphs

International Nuclear Information System (INIS)

Rabinovich, Vladimir S; Roch, Steffen

2007-01-01

Let (X, ρ) be a discrete metric space. We suppose that the group Z n acts freely on X and that the number of orbits of X with respect to this action is finite. Then we call X a Z n -periodic discrete metric space. We examine the Fredholm property and essential spectra of band-dominated operators on l p (X) when 1 n and their limit operators. In the case where X is the set of vertices of a combinatorial graph, the graph structure defines a Schroedinger operator on l p (X) in a natural way. We illustrate our approach by determining the essential spectra of Schroedinger operators with slowly oscillating potential both on zig-zag and on hexagonal graphs, the latter being related to nano-structures

Multiresource allocation and scheduling for periodic soft real-time applications

Science.gov (United States)

Gopalan, Kartik; Chiueh, Tzi-cker

2001-12-01

Real-time applications that utilize multiple system resources, such as CPU, disks, and network links, require coordinated scheduling of these resources in order to meet their end-to-end performance requirements. Most state-of-the-art operating systems support independent resource allocation and deadline-driven scheduling but lack coordination among multiple heterogeneous resources. This paper describes the design and implementation of an Integrated Real-time Resource Scheduler (IRS) that performs coordinated allocation and scheduling of multiple heterogeneous resources on the same machine for periodic soft real-time application. The principal feature of IRS is a heuristic multi-resource allocation algorithm that reserves multiple resources for real-time applications in a manner that can maximize the number of applications admitted into the system in the long run. At run-time, a global scheduler dispatches the tasks of the soft real-time application to individual resource schedulers according to the precedence constraints between tasks. The individual resource schedulers, which could be any deadline based schedulers, can make scheduling decisions locally and yet collectively satisfy a real-time application's performance requirements. The tightness of overall timing guarantees is ultimately determined by the properties of individual resource schedulers. However, IRS maximizes overall system resource utilization efficiency by coordinating deadline assignment across multiple tasks in a soft real-time application.

43 CFR 45.3 - How are time periods computed?

Science.gov (United States)

2010-10-01

... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false How are time periods computed? 45.3... IN FERC HYDROPOWER LICENSES General Provisions § 45.3 How are time periods computed? (a) General... run is not included. (2) The last day of the period is included. (i) If that day is a Saturday, Sunday...

Logic Model Checking of Time-Periodic Real-Time Systems

Science.gov (United States)

Florian, Mihai; Gamble, Ed; Holzmann, Gerard

2012-01-01

In this paper we report on the work we performed to extend the logic model checker SPIN with built-in support for the verification of periodic, real-time embedded software systems, as commonly used in aircraft, automobiles, and spacecraft. We first extended the SPIN verification algorithms to model priority based scheduling policies. Next, we added a library to support the modeling of periodic tasks. This library was used in a recent application of the SPIN model checker to verify the engine control software of an automobile, to study the feasibility of software triggers for unintended acceleration events.

New serial time codes for seismic short period and long period data acquisition systems

International Nuclear Information System (INIS)

Kolvankar, V.G.; Rao, D.S.

1988-01-01

This paper discusses a new time code for time indexing multichannel short period (1 to 25 hz) seismic event data recorded on a single track of magnetic tape in digital format and discusses its usefulness in contrast to Vela time code used in continuous analog multichannel data recording system on multitrack instrumentation tape deck. This paper also discusses another time code, used for time indexing of seismic long period (DC to 2.5 seconds) multichannel data recorded on a single track of magnetic tape in digital format. The time code decoding and display system developed to provide quick access to any desired portion of the tape in both data recording and repro duce system is also discussed. (author). 7 figs

47 CFR 25.133 - Period of construction; certification of commencement of operation.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Period of construction; certification of commencement of operation. 25.133 Section 25.133 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Earth Stations § 25.133 Period...

A Gaussian Process Based Online Change Detection Algorithm for Monitoring Periodic Time Series

Energy Technology Data Exchange (ETDEWEB)

Chandola, Varun [ORNL; Vatsavai, Raju [ORNL

2011-01-01

Online time series change detection is a critical component of many monitoring systems, such as space and air-borne remote sensing instruments, cardiac monitors, and network traffic profilers, which continuously analyze observations recorded by sensors. Data collected by such sensors typically has a periodic (seasonal) component. Most existing time series change detection methods are not directly applicable to handle such data, either because they are not designed to handle periodic time series or because they cannot operate in an online mode. We propose an online change detection algorithm which can handle periodic time series. The algorithm uses a Gaussian process based non-parametric time series prediction model and monitors the difference between the predictions and actual observations within a statistically principled control chart framework to identify changes. A key challenge in using Gaussian process in an online mode is the need to solve a large system of equations involving the associated covariance matrix which grows with every time step. The proposed algorithm exploits the special structure of the covariance matrix and can analyze a time series of length T in O(T^2) time while maintaining a O(T) memory footprint, compared to O(T^4) time and O(T^2) memory requirement of standard matrix manipulation methods. We experimentally demonstrate the superiority of the proposed algorithm over several existing time series change detection algorithms on a set of synthetic and real time series. Finally, we illustrate the effectiveness of the proposed algorithm for identifying land use land cover changes using Normalized Difference Vegetation Index (NDVI) data collected for an agricultural region in Iowa state, USA. Our algorithm is able to detect different types of changes in a NDVI validation data set (with ~80% accuracy) which occur due to crop type changes as well as disruptive changes (e.g., natural disasters).

Time to reach a given level of number of neutrons is stochastic analog of reactor period

International Nuclear Information System (INIS)

Ryazanov, V.V.

2012-01-01

In theory and in practice the operation of nuclear reactors to control the safety of the reactor is widely used deterministic value - the period of the reactor. It is proposed along with the period of the reactor using a stochastic analogue of this magnitude - a random amount of time to achieve a given level of a random process for the number of neutrons in the reactor. The paper discusses various features of the behavior of the mean and variance of time to achieve a specified level. This kind of features can be associated with impaired behavior of the reactor system. Introduced the value of time required to reach the level can be used to monitor and improve the safety of nuclear power plants

The periodically pulsed mode of operation of magnet systems in particle accelerators

International Nuclear Information System (INIS)

Stange, G.

1980-01-01

Since in many applications in particle accelerator technology the beam duty factor, defined by the ratio of beam pulse length to the pulse to pulse period, is very small- typically in the order of 10 - 3 to 10 - 9 - it is interesting to operate the beam optical magnetic system in the periodically pulsed mode as well. Thus, by reducing the average Ohmic losses, it is possible to save energy and material. The pulsed mode of operation of magnet systems is especially adapted to those of linear accelerators and their beam transport systems, since linear accelerators are exclusively operated in this mode. But it is equally suitable for transport systems between cyclic accelerators and large storage rings as they are under development at present. (orig./WL) [de

Effective diffusion in time-periodic linear planar flow

International Nuclear Information System (INIS)

Indeikina, A.; Chang, H.

1993-01-01

It is shown that when a point source of solute is inserted into a time-periodic, unbounded linear planar flow, the large-time, time-average transport of the solute can be described by classical anisotropic diffusion with constant effective diffusion tensors. For a given vorticity and forcing period, elongational flow is shown to be the most dispersive followed by simple shear and rotational flow. Large-time diffusivity along the major axis of the time-average concentration ellipse, whose alignment is predicted from the theory, is shown to increase with vorticity for all flows and decrease with increasing forcing frequency for elongational flow and simple shear. For the interesting case of rotational flow, there exist discrete resonant frequencies where the time-average major diffusivity reaches local maxima equal to the time-average steady flow case with zero forcing frequency

Gynaecomastia and scrotal rhacosis: two aesthetic surgical operations for men in Byzantine times.

Science.gov (United States)

Papadakis, Marios; Manios, Andreas; de Bree, Eelco; Trompoukis, Constantinos; Tsiftsis, Dimitris D

2010-08-01

Nowadays, as in the past, much attention is paid to aesthetic operations in women, while only infrequently have such operations been referred to in males. Generally, male aesthetic surgery was introduced to surgical practise during the 19th century. In this study, we analysed the practise of such operations in Byzantine times and in other ancient cultures with surgical knowledge, i.e. ancient India and China The sixth book of Paul of Aegina's "Epitome of Medicine" was studied for description of aesthetic operations in males in the Byzantine period, since this book is completely devoted to surgery and is generally considered to be the most important reference for surgery in Byzantine times. The original text and its excellent translation by Francis Adams were used. References concerning aesthetic operations for males were identified. Accordingly, historical work and reviews on plastic surgery in ancient India and China were studied. Mainly, two aesthetic surgical procedures for males in the Byzantine period were identified. These two procedures comprise gynaecomastia and rhacosis (scrotal relaxation). Two different techniques were reported for the surgical management of gynaecomastia, through sub-mammary or supra-mammary access. Two procedures were noted for rhacosis, for which Paul of Aegina reproduced the respective chapters from Leonides' and Antyllus' works. Evidence supporting male aesthetic surgery in ancient India and China or elsewhere was not found. Despite the dubious aesthetic result, the existence of different aesthetic surgical techniques in males substantiate the advanced level of surgery achieved by physicians in the Byzantine period. Copyright 2010 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Determination of operation time function for activimeters; Determinacao da funcao tempo de operacao para ativimetros

Energy Technology Data Exchange (ETDEWEB)

Sousa, C.H.S.; Peixoto, J.G.P. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Araujo, G.; Padilha, L.G. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil)

2016-07-01

Radiation detectors must pass periodically recommended quality control tests and standardized to certify the quality of measurements, however, many studies have shown that several parameters can influence the results, however, some instrument components that can not be adjusted during calibrations may have significant importance in measurement results over the operating time. This study sought to determine the influence of the use of time in the activity measurements. The results show a trend of decreased activity measured for equipment with detectors with more operating time. (author)

Multidimensional periodic Schrödinger operator perturbation theory and applications

CERN Document Server

Veliev, Oktay

2015-01-01

The book describes the direct problems and the inverse problem of the multidimensional Schrödinger operator with a periodic potential. This concerns perturbation theory and constructive determination of the spectral invariants and finding the periodic potential from the given Bloch eigenvalues. The unique method of this book derives the asymptotic formulas for Bloch eigenvalues and Bloch functions for arbitrary dimension. Moreover, the measure of the iso-energetic surfaces in the high energy region is construct and estimated. It implies the validity of the Bethe-Sommerfeld conjecture for arbitrary dimensions and arbitrary lattices. Using the perturbation theory constructed in this book, the spectral invariants of the multidimensional operator from the given Bloch eigenvalues are determined. Some of these invariants are explicitly expressed by the Fourier coefficients of the potential. This way the possibility to determine the potential constructively by using Bloch eigenvalues as input data is given. In the ...

ASPECTS REGARDING THE SETTING OF TIME STANDARDS FOR THE PRODUCTION AND SEWING OPERATIONS

Directory of Open Access Journals (Sweden)

SECAN Cristina

2014-05-01

Full Text Available This paper presents the technological process of manufacture of a shoe for women in IL system in order to establish the time and the production norm in the processing-sewing procedure. The sequence of operations is presented in a case study that analyzed how can be obtained the upper assembly of a footwear product that later becomes integral part into the finished product. Drawing up the technological process is done considering both the manual operations and the manual-mechanical operations for processing and assembling the parts that make the whole upper assembly by gluing the parts, by seaming and securing the joints. The type of equipment chosen to carry out operations is influencing through its productivity the necessary material calculated and hence the labour force required. The amount of time consists of time needed for preparation-finishing time, operative time, time of working place service and time of regulated interruptions. These periods of times were determined basically by timing assistance of the manufacturing process throughout its development. Production norm is calculated on the basis of the standard time, taking into account that it represents the amount of products manufactured in a work shift In order to improve the process by reducing the time of production and the number of workers engaged we are considering the automation of the manufacturing process by using modern methods using laser cutting or cutting under running water, automatic sewing machines, strip conveyor belts with pace imposed etc.

Operational quantum theory without predefined time

International Nuclear Information System (INIS)

Oreshkov, Ognyan; Cerf, Nicolas J

2016-01-01

The standard formulation of quantum theory assumes a predefined notion of time. This is a major obstacle in the search for a quantum theory of gravity, where the causal structure of space-time is expected to be dynamical and fundamentally probabilistic in character. Here, we propose a generalized formulation of quantum theory without predefined time or causal structure, building upon a recently introduced operationally time-symmetric approach to quantum theory. The key idea is a novel isomorphism between transformations and states which depends on the symmetry transformation of time reversal. This allows us to express the time-symmetric formulation in a time-neutral form with a clear physical interpretation, and ultimately drop the assumption of time. In the resultant generalized formulation, operations are associated with regions that can be connected in networks with no directionality assumed for the connections, generalizing the standard circuit framework and the process matrix framework for operations without global causal order. The possible events in a given region are described by positive semidefinite operators on a Hilbert space at the boundary, while the connections between regions are described by entangled states that encode a nontrivial symmetry and could be tested in principle. We discuss how the causal structure of space-time could be understood as emergent from properties of the operators on the boundaries of compact space-time regions. The framework is compatible with indefinite causal order, timelike loops, and other acausal structures. (paper)

The epidemiology of operations performed by the National Sea Rescue Institute of South Africa over a 5-year period.

Science.gov (United States)

Erasmus, Elaine; Robertson, Cleeve; van Hoving, Daniel Jacobus

2018-01-01

Injuries remain a major contributor of morbidity and mortality worldwide, with drowning accounting for 7% of all injury-related deaths with rates of between 4 and 8 per 100,000. The African region has death rates comparable to most low-income countries. Non-fatal drowning in Africa remains unquantified but it is estimated to be ten times higher than the fatal drowning rate. Timely search and rescue, initial resuscitation and rapid transportation to definitive care play a crucial role in preventing injury- related morbidity and mortality. The National Sea Rescue Institute (NSRI) of South Africa is a non-profit organisation responsible for ~97% of maritime search and rescue operations in South Africa (including inland navigable waters). The aim of the study was to describe the epidemiology of operations performed by the NSRI of South Africa over a 5-year period. The NSRI operational database was analysed from 1 January 2010 to 31 December 2014. Summary statistics are presented. The NSRI launched 3281 operations over the study period. Marked seasonal variation were noticeable with peak periods in December and January, corresponding to the South African summer holiday season. Water-based operations (67.6%) were the most frequent operation performed. The NSRI assisted 3399 individuals of which 77% were male. The mean age of rescued persons was 42 years. Eight hundred and thirty-six (25%) individuals had non-fatal injuries or illnesses requiring medical assistance. Medical emergencies (35%), traumatic injuries (32.8%), and non-fatal drownings (23%) were the most common types of injury and illness. The majority of the 184 (18%) deaths recorded were due to drowning (75%). Injury and illness, specifically drowning utilise a large proportion of search and rescue services. The results suggest further preventative measures and public health strategies be implemented to minimise traumatic and medical incident severity and subsequent casualties at sea.

On the time evolution operator for time-dependent quadratic Hamiltonians

International Nuclear Information System (INIS)

Fernandez, F.M.

1989-01-01

The Schroedinger equation with a time-dependent quadratic Hamiltonian is investigated. The time-evolution operator is written as a product of exponential operators determined by the Heisenberg equations of motion. This product operator is shown to be global in the occupation number representation when the Hamiltonian is Hermitian. The success of some physical applications of the product-form representation is explained

Track 6: safety and risk management. Plant operational risk management. Plant Configuration Risk Assessment Methodology Development for Periodic Maintenance

International Nuclear Information System (INIS)

Yang, Huichang; Chung, Chang Hyun; Sung, Key Yong

2001-01-01

plant risk level. Such a change in the arrangement of the plant equipment and system at a given time period can be represented as the plant configuration. The plant configuration risk assessment methodology that was developed during this study consists of six steps, as follows: 1. Identification of plant configuration: In this step, various events that occurred in the plant should be identified through a review of the plant operation records such as the periodic maintenance and inspection schedules, maintenance or repair request logs, trouble reports, and other documents related to operational activity. 2. Evaluation of probabilistic risk assessment (PRA) model and computer codes: For the effective evaluation of plant risk during normal operation, an appropriate plant risk model should 273 be used, and the capability of computer codes should be evaluated. There might be numerous events that require the maintenance activity during normal operation. To handle these events during the risk calculation, an optimized plant PRA model and a risk analysis tool of fast calculation capacity are needed. 3. Development of baseline risk model and evaluation of baseline risk: The baseline risk model is a risk model similar to that used for the level 1 PRA, but the maintenance-related events are excluded. This methodology focuses on the relative risk change caused by the usual plant events. For this purpose, the baseline risk that will be the reference of risk variation should be evaluated as reasonably as possible. 4. Analysis of components and systems: For the detailed risk analysis, it is useful to perform the importance analysis for the target components or systems before calculating the plant risks. In terms of system unavailability analysis and importance analysis, information of specific components and systems should be performed for the detailed risk analysis 5. Evaluation of configuration risks and sensitivity analysis: Using the configuration and the system information from

Periodic Virtual Cell Manufacturing (P-VCM) - Concept, Design and Operation

NARCIS (Netherlands)

Slomp, Jannes; Krushinsky, Dimitry; Caprihan, Rahul

2011-01-01

This paper presents and discusses the concept of Periodic Virtual Cell Manufacturing (P-VCM). After giving an illustrative example of the operation and design complexity of a P-VCM system, we present an industrial case to study the applicability of the concept. The illustrative example and the

Time-delayed feedback technique for suppressing instabilities in time-periodic flow

Science.gov (United States)

Shaabani-Ardali, Léopold; Sipp, Denis; Lesshafft, Lutz

2017-11-01

A numerical method is presented that allows to compute time-periodic flow states, even in the presence of hydrodynamic instabilities. The method is based on filtering nonharmonic components by way of delayed feedback control, as introduced by Pyragas [Phys. Lett. A 170, 421 (1992), 10.1016/0375-9601(92)90745-8]. Its use in flow problems is demonstrated here for the case of a periodically forced laminar jet, subject to a subharmonic instability that gives rise to vortex pairing. The optimal choice of the filter gain, which is a free parameter in the stabilization procedure, is investigated in the context of a low-dimensional model problem, and it is shown that this model predicts well the filter performance in the high-dimensional flow system. Vortex pairing in the jet is efficiently suppressed, so that the unstable periodic flow state in response to harmonic forcing is accurately retrieved. The procedure is straightforward to implement inside any standard flow solver. Memory requirements for the delayed feedback control can be significantly reduced by means of time interpolation between checkpoints. Finally, the method is extended for the treatment of periodic problems where the frequency is not known a priori. This procedure is demonstrated for a three-dimensional cubic lid-driven cavity in supercritical conditions.

Time-critical multirate scheduling using contemporary real-time operating system services

Science.gov (United States)

Eckhardt, D. E., Jr.

1983-01-01

Although real-time operating systems provide many of the task control services necessary to process time-critical applications (i.e., applications with fixed, invariant deadlines), it may still be necessary to provide a scheduling algorithm at a level above the operating system in order to coordinate a set of synchronized, time-critical tasks executing at different cyclic rates. The scheduling requirements for such applications and develops scheduling algorithms using services provided by contemporary real-time operating systems.

Measuring quality indicators in the operating room: cleaning and turnover time.

Science.gov (United States)

Jericó, Marli de Carvalho; Perroca, Márcia Galan; da Penha, Vivian Colombo

2011-01-01

This exploratory-descriptive study was carried out in the Surgical Center Unit of a university hospital aiming to measure time spent with concurrent cleaning performed by the cleaning service and turnover time and also investigated potential associations between cleaning time and the surgery's magnitude and specialty, period of the day and the room's size. The sample consisted of 101 surgeries, computing cleaning time and 60 surgeries, computing turnover time. The Kaplan-Meier method was used to analyze time and Pearson's correlation to study potential correlations. The time spent in concurrent cleaning was 7.1 minutes and turnover time was 35.6 minutes. No association between cleaning time and the other variables was found. These findings can support nurses in the efficient use of resources thereby speeding up the work process in the operating room.

18 CFR 376.209 - Procedures during periods of emergency requiring activation of the Continuity of Operations Plan.

Science.gov (United States)

2010-04-01

... periods of emergency requiring activation of the Continuity of Operations Plan. 376.209 Section 376.209... of the Continuity of Operations Plan. (a)(1) The Commission's Continuity of Operations Plan is...) During periods when the Continuity of Operations Plan is activated, the Commission will continue to act...

Criteria for extending the operation periods of thermoelectric converters based on IV-VI compounds

Energy Technology Data Exchange (ETDEWEB)

Sadia, Yatir, E-mail: yatttir@yahoo.com [Department of Materials Engineering, Ben-Gurion University of the Negev, Beer-Sheva (Israel); Ohaion-Raz, Tsion [Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva (Israel); Ben-Yehuda, Ohad; Korngold, Meidad; Gelbstein, Yaniv [Department of Materials Engineering, Ben-Gurion University of the Negev, Beer-Sheva (Israel)

2016-09-15

The recent energy demands affected by the dilution of conventional energy resources and the growing awareness of environmental considerations, had positioned the research of renewable energy conversion methods in general and of thermoelectric direct conversion of thermal into electrical energies in particular, in the forefront of the currently active applicative sciences. IV-VI thermoelectric compounds (e.g. GeTe, PbTe and SnTe) and their alloys comprise some of the most efficient thermoelectric compositions ever reported. Yet a proper utilization of such materials in practical thermoelectric devices, still requires an overcoming the so-called technological “valley of death”, including among others, transport properties' degradation, due to sublimation of volatile Te rich species, while being subjected to elevated temperatures for long periods of time. In an attempt to establish practical operation criteria for extending the operation periods of such thermoelectric converters, it is currently shown based on thermal gravimetric and metallurgical considerations that such harmful sublimation can be practically bridged over by limiting the maximal operating temperatures to the 410–430 °C range for GeTe rich alloys and to 510–530 °C for PbTe and SnTe rich alloys, depending of the thermoelectric leg's diameter. - Graphical abstract: Evaporation rate in the GeTe and PbTe system showing the measured evaporation rates and the maximal operating temperatures for different compositions. In addition, the microstructure after evaporation is shown for PbTe, TAGS-85, and doped Pb{sub 0.13}Ge{sub 087}Te. Display Omitted - Highlights: • Evaporation rates of GeTe and PbTe based thermoelectric compounds were determined. • A criterion for their maximum operating temperature was established. • The materials showed phase separations and off-stoichiometry compositions.

On positive periodic solution of periodic competition Lotka-Volterra system with time delay and diffusion

International Nuclear Information System (INIS)

Sun Wen; Chen Shihua; Hong Zhiming; Wang Changping

2007-01-01

A two-species periodic competition Lotka-Volterra system with time delay and diffusion is investigated. Some sufficient conditions of the existence of positive periodic solution are established for the system by using the continuation theorem of coincidence degree theory

A technique to detect periodic and non-periodic ultra-rapid flux time variations with standard radio-astronomical data

Science.gov (United States)

Borra, Ermanno F.; Romney, Jonathan D.; Trottier, Eric

2018-06-01

We demonstrate that extremely rapid and weak periodic and non-periodic signals can easily be detected by using the autocorrelation of intensity as a function of time. We use standard radio-astronomical observations that have artificial periodic and non-periodic signals generated by the electronics of terrestrial origin. The autocorrelation detects weak signals that have small amplitudes because it averages over long integration times. Another advantage is that it allows a direct visualization of the shape of the signals, while it is difficult to see the shape with a Fourier transform. Although Fourier transforms can also detect periodic signals, a novelty of this work is that we demonstrate another major advantage of the autocorrelation, that it can detect non-periodic signals while the Fourier transform cannot. Another major novelty of our work is that we use electric fields taken in a standard format with standard instrumentation at a radio observatory and therefore no specialized instrumentation is needed. Because the electric fields are sampled every 15.625 ns, they therefore allow detection of very rapid time variations. Notwithstanding the long integration times, the autocorrelation detects very rapid intensity variations as a function of time. The autocorrelation could also detect messages from Extraterrestrial Intelligence as non-periodic signals.

Retroperitoneal laparoscopic nephrectomy: the effect of the learning curve, and concentrating expertise, on operating times.

Science.gov (United States)

Skinner, Adrian; Maoate, Kiki; Beasley, Spencer

2010-05-01

Laparoscopic nephrectomy is an accepted alternative to open nephrectomy. We analyzed our first 80 procedures of laparoscopic nephrectomy to evaluate the effect of experience and configuration of service on operative times. A retrospective review of 80 consecutive children who underwent retroperitoneal laparoscopic nephrectomy or heminephrectomy during an 11-year period from 1997 at Christchurch Hospital (Christchurch, New Zealand) was conducted. Operative times, in relation to the experience of the surgeon for this procedure, were analyzed. Four surgeons, assisted by an annually rotating trainee registrar, performed the procedure in 26 girls and 54 boys (range, 8 months to 15 years). Operating times ranged from 38 to 225 minutes (mean, 104). The average operative time fell from 105 to 90 minutes. One surgeon performed 40% of the procedures and assisted with a further 55%. The operative times for all surgeons showed a tendency to reduce, but this was not marked. Most procedures were performed by two surgeons working together, although one surgeon was involved in the majority of cases. The lead surgeon is often assisted by a fellow consultant colleague. Operative times were influenced by experience, but not markedly so. The shorter operative times and minimal "learning curve," compared with other reported series, may, in part, be due to the involvement of two surgeons experienced in laparoscopy for the majority of cases.

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.

Schrödinger operators on a periodically broken zigzag carbon ...

Indian Academy of Sciences (India)

In this paper, we study the spectra of Schrödinger operators on zigzag carbon nanotubes, which are broken by abrasion or during refining process. Throughout this paper, we assume that the carbon nanotubes are broken periodically and we deal with one of those models. Making use of the Floquet–Bloch theory, we ...

Abundant spontaneous VLFE activities in Cascadia during ETS and inter-ETS time periods

Science.gov (United States)

Ghosh, A.; Hutchison, A. A.; Hawthorne, J.

2017-12-01

Very low frequency earthquakes (VLFEs) are discrete seismic events associated with episodic tremor and slip (ETS) events. They are rich in 20-50s energy and depleted in higher frequencies compared to regular local earthquakes of similar magnitudes. VLFEs can be as large as Mw 4.0, and potentially release much more seismic moment than the tremor/LFE activities, making them a critical event determining stress evolution during slow earthquakes [Ghosh et al., 2015]. Their underlying physics and relationship with tremor/LFE, however, are still unclear. In Cascadia, the majority of the VLFEs found so far are clustered near the areas of high geodetic slip during ETS events [Ghosh et al., 2015; Hutchison and Ghosh, 2016]. Interestingly, we found VLFE activity has its own dynamics and can occur independent of tremor/LFE activity. For example, during the 2014 ETS event in northern Cascadia, VLFEs are found to be asynchronous with tremor activity, both in space and time [Hutchison and Ghosh, 2016]. We use a matched filter technique to detect thousands of VLFEs over an ETS-cycle, and perhaps more interestingly, even between ETS events. VLFE activities peak during ETS events, but significant VLFE activity is detected during the inter-ETS time period. Analyses of strainmeter data near the VLFE locations suggest statistically significant strain rate increases during VLFE time periods compared to the background. We suggest that VLFE is a distinct type of seismic radiation different from tremor/LFE, and can operate independently from tremor activities. This is in contrast to a model suggesting that VLFE signals may be a result of many LFE signals arriving at seismic stations in a short time period [Gomberg et al., 2016]. We are making a consistent catalog of VLFE in Cascadia for longer time period. Systematic study of VLFEs is going to provide new insights into the mechanism of slow earthquakes and its relationship with tremor/LFE and slow slip.

Switched periodic systems in discrete time: stability and input-output norms

Science.gov (United States)

Bolzern, Paolo; Colaneri, Patrizio

2013-07-01

This paper deals with the analysis of stability and the characterisation of input-output norms for discrete-time periodic switched linear systems. Such systems consist of a network of time-periodic linear subsystems sharing the same state vector and an exogenous switching signal that triggers the jumps between the subsystems. The overall system exhibits a complex dynamic behaviour due to the interplay between the time periodicity of the subsystem parameters and the switching signal. Both arbitrary switching signals and signals satisfying a dwell-time constraint are considered. Linear matrix inequality conditions for stability and guaranteed H2 and H∞ performances are provided. The results heavily rely on the merge of the theory of linear periodic systems and recent developments on switched linear time-invariant systems.

Effectiveness Analysis of a Part-Time Rapid Response System During Operation Versus Nonoperation.

Science.gov (United States)

Kim, Youlim; Lee, Dong Seon; Min, Hyunju; Choi, Yun Young; Lee, Eun Young; Song, Inae; Park, Jong Sun; Cho, Young-Jae; Jo, You Hwan; Yoon, Ho Il; Lee, Jae Ho; Lee, Choon-Taek; Do, Sang Hwan; Lee, Yeon Joo

2017-06-01

To evaluate the effect of a part-time rapid response system on the occurrence rate of cardiopulmonary arrest by comparing the times of rapid response system operation versus nonoperation. Retrospective cohort study. A 1,360-bed tertiary care hospital. Adult patients admitted to the general ward were screened. Data were collected over 36 months from rapid response system implementation (October 2012 to September 2015) and more than 45 months before rapid response system implementation (January 2009 to September 2012). None. The rapid response system operates from 7 AM to 10 PM on weekdays and from 7 AM to 12 PM on Saturdays. Primary outcomes were the difference of cardiopulmonary arrest incidence between pre-rapid response system and post-rapid response system periods and whether the rapid response system operating time affects the cardiopulmonary arrest incidence. The overall cardiopulmonary arrest incidence (per 1,000 admissions) was 1.43. Although the number of admissions per month and case-mix index were increased (3,555.18 vs 4,564.72, p times (0.82 vs 0.49/1,000 admissions; p = 0.001) but remained similar during rapid response system nonoperating times (0.77 vs 0.73/1,000 admissions; p = 0.729). The implementation of a part-time rapid response system reduced the cardiopulmonary arrest incidence based on the reduction of cardiopulmonary arrest during rapid response system operating times. Further analysis of the cost effectiveness of part-time rapid response system is needed.

Timing of millennial-scale climate change in Antarctica and Greenland during the last glacial period

DEFF Research Database (Denmark)

Blunier, T; Brook, E J

2001-01-01

A precise relative chronology for Greenland and West Antarctic paleotemperature is extended to 90,000 years ago, based on correlation of atmospheric methane records from the Greenland Ice Sheet Project 2 and Byrd ice cores. Over this period, the onset of seven major millennial-scale warmings in A....... This pattern provides further evidence for the operation of a "bipolar see-saw" in air temperatures and an oceanic teleconnection between the hemispheres on millennial time scales....

Forecasting with periodic autoregressive time series models

NARCIS (Netherlands)

Ph.H.B.F. Franses (Philip Hans); R. Paap (Richard)

1999-01-01

textabstractThis paper is concerned with forecasting univariate seasonal time series data using periodic autoregressive models. We show how one should account for unit roots and deterministic terms when generating out-of-sample forecasts. We illustrate the models for various quarterly UK consumption

15 CFR 325.4 - Calculating time periods.

Science.gov (United States)

2010-01-01

... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Calculating time periods. 325.4 Section 325.4 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE MISCELLANEOUS REGULATIONS EXPORT TRADE CERTIFICATES...

Efficient Fourier-based algorithms for time-periodic unsteady problems

Science.gov (United States)

Gopinath, Arathi Kamath

2007-12-01

This dissertation work proposes two algorithms for the simulation of time-periodic unsteady problems via the solution of Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations. These algorithms use a Fourier representation in time and hence solve for the periodic state directly without resolving transients (which consume most of the resources in a time-accurate scheme). In contrast to conventional Fourier-based techniques which solve the governing equations in frequency space, the new algorithms perform all the calculations in the time domain, and hence require minimal modifications to an existing solver. The complete space-time solution is obtained by iterating in a fifth pseudo-time dimension. Various time-periodic problems such as helicopter rotors, wind turbines, turbomachinery and flapping-wings can be simulated using the Time Spectral method. The algorithm is first validated using pitching airfoil/wing test cases. The method is further extended to turbomachinery problems, and computational results verified by comparison with a time-accurate calculation. The technique can be very memory intensive for large problems, since the solution is computed (and hence stored) simultaneously at all time levels. Often, the blade counts of a turbomachine are rescaled such that a periodic fraction of the annulus can be solved. This approximation enables the solution to be obtained at a fraction of the cost of a full-scale time-accurate solution. For a viscous computation over a three-dimensional single-stage rescaled compressor, an order of magnitude savings is achieved. The second algorithm, the reduced-order Harmonic Balance method is applicable only to turbomachinery flows, and offers even larger computational savings than the Time Spectral method. It simulates the true geometry of the turbomachine using only one blade passage per blade row as the computational domain. In each blade row of the turbomachine, only the dominant frequencies are resolved, namely

Statistical analysis of first period of operation of FTU Tokamak

International Nuclear Information System (INIS)

Crisanti, F.; Apruzzese, G.; Frigione, D.; Kroegler, H.; Lovisetto, L.; Mazzitelli, G.; Podda, S.

1996-09-01

On the FTU Tokamak the plasma physics operations started on the 20/4/90. The first plasma had a plasma current Ip=0.75 MA for about a second. The experimental phase lasted until 7/7/94, when a long shut-down begun for installing the toroidal limiter in the inner side of the vacuum vessel. In these four years of operations plasma experiments have been successfully exploited, e.g. experiments of single and multiple pellet injections; full current drive up to Ip=300 KA was obtained by using waves at the frequency of the Lower Hybrid; analysis of ohmic plasma parameters with different materials (from the low Z silicon to high Z tungsten) as plasma facing element was performed. In this work a statistical analysis of the full period of operation is presented. Moreover, a comparison with the statistical data from other Tokamaks is attempted

Effect of Resident Involvement on Operative Time and Operating Room Staffing Costs.

Science.gov (United States)

Allen, Robert William; Pruitt, Mark; Taaffe, Kevin M

The operating room (OR) is a major driver of hospital costs; therefore, operative time is an expensive resource. The training of surgical residents must include time spent in the OR, but that experience comes with a cost to the surgeon and hospital. The objective of this article is to determine the effect of surgical resident involvement in the OR on operative time and subsequent hospital labor costs. The Kruskal-Wallis statistical test is used to determine whether or not there is a difference in operative times between 2 groups of cases (with residents and without residents). This difference leads to an increased cost in associated hospital labor costs for the group with the longer operative time. Cases were performed at Greenville Memorial Hospital. Greenville Memorial Hospital is part of the larger healthcare system, Greenville Health System, located in Greenville, SC and is a level 1 trauma center with up to 33 staffed ORs. A total of 84,997 cases were performed at the partnering hospital between January 1st, 2011 and July 31st, 2015. Cases were only chosen for analysis if there was only one CPT code associated with the case and there were more than 5 observations for each group being studied. This article presents a comprehensive retrospective analysis of 29,134 cases covering 246 procedures. The analysis shows that 45 procedures took significantly longer with a resident present in the room. The average increase in operative time was 4.8 minutes and the cost per minute of extra operative time was determined to be $9.57 per minute. OR labor costs at the partnering hospital was found to be $2,257,433, or $492,889 per year. Knowing the affect on operative time and OR costs allows managers to make smart decisions when considering alternative educational and training techniques. In addition, knowing the connection between residents in the room and surgical duration could help provide better estimates of surgical time in the future and increase the predictability of

Time-periodic solutions of the Benjamin-Ono equation

Energy Technology Data Exchange (ETDEWEB)

Ambrose , D.M.; Wilkening, Jon

2008-04-01

We present a spectrally accurate numerical method for finding non-trivial time-periodic solutions of non-linear partial differential equations. The method is based on minimizing a functional (of the initial condition and the period) that is positive unless the solution is periodic, in which case it is zero. We solve an adjoint PDE to compute the gradient of this functional with respect to the initial condition. We include additional terms in the functional to specify the free parameters, which, in the case of the Benjamin-Ono equation, are the mean, a spatial phase, a temporal phase and the real part of one of the Fourier modes at t = 0. We use our method to study global paths of non-trivial time-periodic solutions connecting stationary and traveling waves of the Benjamin-Ono equation. As a starting guess for each path, we compute periodic solutions of the linearized problem by solving an infinite dimensional eigenvalue problem in closed form. We then use our numerical method to continue these solutions beyond the realm of linear theory until another traveling wave is reached (or until the solution blows up). By experimentation with data fitting, we identify the analytical form of the solutions on the path connecting the one-hump stationary solution to the two-hump traveling wave. We then derive exact formulas for these solutions by explicitly solving the system of ODE's governing the evolution of solitons using the ansatz suggested by the numerical simulations.

Time-periodic solutions of the Benjamin-Ono equation

International Nuclear Information System (INIS)

Ambrose, D.M.; Wilkening, Jon

2008-01-01

We present a spectrally accurate numerical method for finding non-trivial time-periodic solutions of non-linear partial differential equations. The method is based on minimizing a functional (of the initial condition and the period) that is positive unless the solution is periodic, in which case it is zero. We solve an adjoint PDE to compute the gradient of this functional with respect to the initial condition. We include additional terms in the functional to specify the free parameters, which, in the case of the Benjamin-Ono equation, are the mean, a spatial phase, a temporal phase and the real part of one of the Fourier modes at t = 0. We use our method to study global paths of non-trivial time-periodic solutions connecting stationary and traveling waves of the Benjamin-Ono equation. As a starting guess for each path, we compute periodic solutions of the linearized problem by solving an infinite dimensional eigenvalue problem in closed form. We then use our numerical method to continue these solutions beyond the realm of linear theory until another traveling wave is reached (or until the solution blows up). By experimentation with data fitting, we identify the analytical form of the solutions on the path connecting the one-hump stationary solution to the two-hump traveling wave. We then derive exact formulas for these solutions by explicitly solving the system of ODE's governing the evolution of solitons using the ansatz suggested by the numerical simulations

Guidance concepts for time-based flight operations

Science.gov (United States)

Vicroy, Dan D.

1990-01-01

Airport congestion and the associated delays are severe in today's airspace system and are expected to increase. NASA and the FAA is investigating various methods of alleviating this problem through new technology and operational procedures. One concept for improving airspace productivity is time-based control of aircraft. Research to date has focused primarily on the development of time-based flight management systems and Air Traffic Control operational procedures. Flight operations may, however, require special onboard guidance in order to satisfy the Air Traffic Control imposed time constraints. The results are presented of a simulation study aimed at evaluating several time-based guidance concepts in terms of tracking performance, pilot workload, and subjective preference. The guidance concepts tested varied in complexity from simple digital time-error feedback to an advanced time-referenced-energy guidance scheme.

Motor operated valve stroke timing; is there value?

International Nuclear Information System (INIS)

Green, K.; Rosch, F. Jr.; Neckowicz, T.

1990-01-01

Both ASME Section XI, Subsection IWV and ASME/ANSI OMa-1988, Part 10 require stroke timing of certain power operated valves. This requirement is intended to detect valve degradation and subsequent maintenance, repair or replacement needs. However, the adequacy of stroke timing, especially for motor operated valves, has met much skepticism in the industry. This paper will demonstrate that stroke timing for ac motor operated valves is inadequate and provide a non-intrusive testing alternative. It will also discuss the value of stroke timing for dc motor operated valves

Real-time reservoir operation considering non-stationary inflow prediction

Science.gov (United States)

Zhao, J.; Xu, W.; Cai, X.; Wang, Z.

2011-12-01

Stationarity of inflow has been a basic assumption for reservoir operation rule design, which is now facing challenges due to climate change and human interferences. This paper proposes a modeling framework to incorporate non-stationary inflow prediction for optimizing the hedging operation rule of large reservoirs with multiple-year flow regulation capacity. A multi-stage optimization model is formulated and a solution algorithm based on the optimality conditions is developed to incorporate non-stationary annual inflow prediction through a rolling, dynamic framework that updates the prediction from period to period and adopt the updated prediction in reservoir operation decision. The prediction model is ARIMA(4,1,0), in which parameter 4 stands for the order of autoregressive, 1 represents a linear trend, and 0 is the order of moving average. The modeling framework and solution algorithm is applied to the Miyun reservoir in China, determining a yearly operating schedule during the period from 1996 to 2009, during which there was a significant declining trend of reservoir inflow. Different operation policy scenarios are modeled, including standard operation policy (SOP, matching the current demand as much as possible), hedging rule (i.e., leaving a certain amount of water for future to avoid large risk of water deficit) with forecast from ARIMA (HR-1), hedging (HR) with perfect forecast (HR-2 ). Compared to the results of these scenarios to that of the actual reservoir operation (AO), the utility of the reservoir operation under HR-1 is 3.0% lower than HR-2, but 3.7% higher than the AO and 14.4% higher than SOP. Note that the utility under AO is 10.3% higher than that under SOP, which shows that a certain level of hedging under some inflow prediction or forecast was used in the real-world operation. Moreover, the impacts of discount rate and forecast uncertainty level on the operation will be discussed.

Body Mass Index and Operating Times in Vascular Procedures

Directory of Open Access Journals (Sweden)

M. Durup-Dickenson

Full Text Available : Introduction: The influence of body mass index (BMI on operating times in central and peripheral vascular surgical procedures was investigated. Report: A national cohort of Danish patients who underwent a vascular procedure between 1983 and 2012 was used for analysis. Data were analysed with pairwise comparisons of BMI groups for operating times using the independent samples Kruskall–Wallis test. Discussion: A total of 3,255 carotid endarterectomies; 6,885 central vascular procedures; and 4,488 peripheral bypasses were included for the analysis. Median operating times for carotid endarterectomy and central vascular procedures were, respectively, 5 and 15 minutes longer in obese patients than in normal weight patients. This represents a 7% and 10% increase in median operating times, respectively. Linear and multi-adjusted linear regressions were conducted adjusting for confounders, showing a significant correlation between BMI and operating time. Obesity significantly increased the operating times in carotid endarterectomy and central vascular procedures. These may have ramifications for the individual operative stress but not necessarily on logistical operation planning. Keywords: Body mass index (BMI, Obesity, Operating time, Surgery, Vascular surgical procedures

Microprocessor controlled digital period meter

International Nuclear Information System (INIS)

Keefe, D.J.; McDowell, W.P.; Rusch, G.K.

1980-01-01

A microprocessor controlled digital period meter has been developed and tested operationally on a reactor at Argonne National Laboratory. The principle of operation is the mathematical relationship between asymptotic periods and pulse counting circuitry. This relationship is used to calculate and display the reactor periods over a range of /plus or minus/1 second to /plus or minus/999 seconds. The time interval required to update each measurement automatically varies from 8 seconds at the lowest counting rates to 2 seconds at higher counting rates. The paper will describe hardware and software design details and show the advantages of this type of Period Meter over the conventional circuits. 1 ref

Quasi-periodic Schroedinger operators in one dimension, absolutely continuous spectra, Bloch waves, and integrable Hamiltonian systems

International Nuclear Information System (INIS)

Chierchia, L.

1986-01-01

In the first chapter, the eigenvalue problem for a periodic Schroedinger operator, Lf = (-d 2 /dx 2 + v)f = Ef, is viewed as a two-dimensional Hamiltonian system which is integrable in the sense of Arnold and Liouville. With the aid of the Floquet-BLoch theory, it is shown that such a system is conjugate to two harmonic oscillators with frequencies α and omega, being the rotation number for L and 2π/omega the period of the potential v. This picture is generalized in the second chapter, to quasi periodic Schroedinger operators, L/sub epsilon/, with highly irrational frequencies (omega 1 , ..., omega/sub d/), which are a small perturbation of periodic operators. In the last chapter, the absolutely continuous spectrum σ/sub ac/ of a general quasi-periodic Schroedinger operators is considered. The Radon-Nikodym derivatives (with respect to Lebesgue measure) of the spectral measures are computed in terms of special independent eigensolutions existing for almost ever E in σ/sub ac/. Finally, it is shown that weak Bloch waves always exist for almost ever E in σ/sub ac/ and the question of the existence of genuine Bloch waves is turned into a regularity problem for a certain nonlinear partial differential equation on a d-dimensional torus

Concepts for operational period panel seal design at the Waste Isolation Pilot Plant

International Nuclear Information System (INIS)

Hansen, F.D.; Lin, M.S.; Van Sambeek, L.L.

1993-07-01

Concepts for underground panel or drift seals at the Waste Isolation Pilot Plant are developed to satisfy sealing requirements of the operational period. The concepts are divided into two groups. In the ''NOW'' group, design concepts are considered in which a sleeve structure is installed in the panel access immediately after excavation and before waste is emplaced. In the ''LATER'' group, no special measures are taken during excavation or before waste emplacement; the seal is installed at a later date, perhaps up to 35 years after the drift is excavated. Three concepts are presented in both the NOW and LATER groups. A rigid sleeve, a yielding sleeve, and steel rings with inflatable tubes are proposed as NOW concepts. One steel ring concept and two concrete monoliths are proposed for seals emplaced in older drifts. Advantages and disadvantages are listed for each concept. Based on the available information, it appears most feasible to recommend a LATER concept using a concrete monolith as a preferred seal for the operational period. Each concept includes the potential of remedial grout and/or construction of a chamber that could be used for monitoring leakage from a closed panel during the operational period. Supporting in situ demonstrations of elements of the concepts are recommended

Real-time multi-task operators support system

International Nuclear Information System (INIS)

Wang He; Peng Minjun; Wang Hao; Cheng Shouyu

2005-01-01

The development in computer software and hardware technology and information processing as well as the accumulation in the design and feedback from Nuclear Power Plant (NPP) operation created a good opportunity to develop an integrated Operator Support System. The Real-time Multi-task Operator Support System (RMOSS) has been built to support the operator's decision making process during normal and abnormal operations. RMOSS consists of five system subtasks such as Data Collection and Validation Task (DCVT), Operation Monitoring Task (OMT), Fault Diagnostic Task (FDT), Operation Guideline Task (OGT) and Human Machine Interface Task (HMIT). RMOSS uses rule-based expert system and Artificial Neural Network (ANN). The rule-based expert system is used to identify the predefined events in static conditions and track the operation guideline through data processing. In dynamic status, Back-Propagation Neural Network is adopted for fault diagnosis, which is trained with the Genetic Algorithm. Embedded real-time operation system VxWorks and its integrated environment Tornado II are used as the RMOSS software cross-development. VxGUI is used to design HMI. All of the task programs are designed in C language. The task tests and function evaluation of RMOSS have been done in one real-time full scope simulator. Evaluation results show that each task of RMOSS is capable of accomplishing its functions. (authors)

pH control structure design for a periodically operated membrane separation process

DEFF Research Database (Denmark)

Prado Rubio, Oscar Andres; Jørgensen, Sten Bay; Jonsson, Gunnar Eigil

2012-01-01

A bioreactor integrated with an electrically driven membrane separation process (Reverse Electro-Enhanced Dialysis – REED) is under investigation as potential technology for intensifying lactic acid bioproduction. In this contribution the pH regulation issue in the periodically operated REED module...

Time analysis in astronomy: Tools for periodicity searches

International Nuclear Information System (INIS)

Buccheri, R.; Sacco, B.

1985-01-01

The authors discuss periodicity searches in radio and gamma-ray astronomy with special considerations for pulsar searches. The basic methodologies of fast Fourier transform, Rayleigh test, and epoch folding are reviewed with the main objective to compare cost and sensitivities in different applications. It is found that FFT procedures are convenient in unbiased searches for periodicity in radio astronomy, while in spark chamber gamma-ray astronomy, where the measurements are spread over a long integration time, unbiased searches are very difficult with the existing computing facilities and analyses with a-priori knowledge on the period values to look for are better done using the Rayleigh test with harmonics folding (Z /sub n/ test)

Enhanced diffusion with abnormal temperature dependence in underdamped space-periodic systems subject to time-periodic driving

Science.gov (United States)

Marchenko, I. G.; Marchenko, I. I.; Zhiglo, A. V.

2018-01-01

We present a study of the diffusion enhancement of underdamped Brownian particles in a one-dimensional symmetric space-periodic potential due to external symmetric time-periodic driving with zero mean. We show that the diffusivity can be enhanced by many orders of magnitude at an appropriate choice of the driving amplitude and frequency. The diffusivity demonstrates abnormal (decreasing) temperature dependence at the driving amplitudes exceeding a certain value. At any fixed driving frequency Ω normal temperature dependence of the diffusivity is restored at low enough temperatures, T oscillation frequency at the potential minimum, the diffusivity is shown to decrease with Ω according to a power law, with the exponent related to the transient superdiffusion exponent. This behavior is found similar for the cases of sinusoidal in time and piecewise constant periodic ("square") driving.

Scattering analysis of periodic structures using finite-difference time-domain

CERN Document Server

ElMahgoub, Khaled; Elsherbeni, Atef Z

2012-01-01

Periodic structures are of great importance in electromagnetics due to their wide range of applications such as frequency selective surfaces (FSS), electromagnetic band gap (EBG) structures, periodic absorbers, meta-materials, and many others. The aim of this book is to develop efficient computational algorithms to analyze the scattering properties of various electromagnetic periodic structures using the finite-difference time-domain periodic boundary condition (FDTD/PBC) method. A new FDTD/PBC-based algorithm is introduced to analyze general skewed grid periodic structures while another algor

Lagrangian structures in time-periodic vortical flows

Directory of Open Access Journals (Sweden)

S. V. Kostrykin

2006-01-01

Full Text Available The Lagrangian trajectories of fluid particles are experimentally studied in an oscillating four-vortex velocity field. The oscillations occur due to a loss of stability of a steady flow and result in a regular reclosure of streamlines between the vortices of the same sign. The Eulerian velocity field is visualized by tracer displacements over a short time period. The obtained data on tracer motions during a number of oscillation periods show that the Lagrangian trajectories form quasi-regular structures. The destruction of these structures is determined by two characteristic time scales: the tracers are redistributed sufficiently fast between the vortices of the same sign and much more slowly transported into the vortices of opposite sign. The observed behavior of the Lagrangian trajectories is quantitatively reproduced in a new numerical experiment with two-dimensional model of the velocity field with a small number of spatial harmonics. A qualitative interpretation of phenomena observed on the basis of the theory of adiabatic chaos in the Hamiltonian systems is given. The Lagrangian trajectories are numerically simulated under varying flow parameters. It is shown that the spatial-temporal characteristics of the Lagrangian structures depend on the properties of temporal change in the streamlines topology and on the adiabatic parameter corresponding to the flow. The condition for the occurrence of traps (the regions where the Lagrangian particles reside for a long time is obtained.

Reusable single-port access device shortens operative time and reduces operative costs.

Science.gov (United States)

Shussman, Noam; Kedar, Asaf; Elazary, Ram; Abu Gazala, Mahmoud; Rivkind, Avraham I; Mintz, Yoav

2014-06-01

In recent years, single-port laparoscopy (SPL) has become an attractive approach for performing surgical procedures. The pitfalls of this approach are technical and financial. Financial concerns are due to the increased cost of dedicated devices and prolonged operating room time. Our aim was to calculate the cost of SPL using a reusable port and instruments in order to evaluate the cost difference between this approach to SPL using the available disposable ports and standard laparoscopy. We performed 22 laparoscopic procedures via the SPL approach using a reusable single-port access system and reusable laparoscopic instruments. These included 17 cholecystectomies and five other procedures. Operative time, postoperative length of stay (LOS) and complications were prospectively recorded and were compared with similar data from our SPL database. Student's t test was used for statistical analysis. SPL was successfully performed in all cases. Mean operative time for cholecystectomy was 72 min (range 40-116). Postoperative LOS was not changed from our standard protocols and was 1.1 days for cholecystectomy. The postoperative course was within normal limits for all patients and perioperative morbidity was recorded. Both operative time and length of hospital stay were shorter for the 17 patients who underwent cholecystectomy using a reusable port than for the matched previous 17 SPL cholecystectomies we performed (p cost difference. Operating with a reusable port ended up with an average cost savings of US$388 compared with using disposable ports, and US$240 compared with standard laparoscopy. Single-port laparoscopic surgery is a technically challenging and expensive surgical approach. Financial concerns among others have been advocated against this approach; however, we demonstrate herein that using a reusable port and instruments reduces operative time and overall operative costs, even beyond the cost of standard laparoscopy.

Periodic capacity management under a lead-time performance constraint

NARCIS (Netherlands)

Büyükkaramikli, N.C.; Bertrand, J.W.M.; Ooijen, van H.P.G.

2013-01-01

In this paper, we study a production system that operates under a lead-time performance constraint which guarantees the completion of an order before a pre-determined lead-time with a certain probability. The demand arrival times and the service requirements for the orders are random. To reduce the

Operator of Time and Generalized Schrödinger Equation

Directory of Open Access Journals (Sweden)

Slobodan Prvanović

2018-01-01

Full Text Available The equation describing the change of the state of the quantum system with respect to energy is introduced within the framework of the self-adjoint operator of time in nonrelativistic quantum mechanics. In this proposal, the operator of time appears to be the generator of the change of the energy, while the operator of energy that is conjugate to the operator of time generates the time evolution. Two examples, one with discrete time and the other with continuous one, are given and the generalization of Schrödinger equation is proposed.

Kajian dan Implementasi Real Time Operating System pada Single Board Computer Berbasis Arm

Directory of Open Access Journals (Sweden)

Wiedjaja A

2014-06-01

Full Text Available Operating System is an important software in computer system. For personal and office use the operating system is sufficient. However, to critical mission applications such as nuclear power plants and braking system on the car (auto braking system which need a high level of reliability, it requires operating system which operates in real time. The study aims to assess the implementation of the Linux-based operating system on a Single Board Computer (SBC ARM-based, namely Pandaboard ES with the Dual-core ARM Cortex-A9, TI OMAP 4460 type. Research was conducted by the method of implementation of the General Purpose OS Ubuntu 12:04 OMAP4-armhf-RTOS and Linux 3.4.0-rt17 + on PandaBoard ES. Then research compared the latency value of each OS on no-load and with full-load condition. The results obtained show the maximum latency value of RTOS on full load condition is at 45 uS, much smaller than the maximum value of GPOS at full-load at 17.712 uS. The lower value of latency demontrates that the RTOS has ability to run the process in a certain period of time much better than the GPOS.

Modeling of human operator dynamics in simple manual control utilizing time series analysis. [tracking (position)

Science.gov (United States)

Agarwal, G. C.; Osafo-Charles, F.; Oneill, W. D.; Gottlieb, G. L.

1982-01-01

Time series analysis is applied to model human operator dynamics in pursuit and compensatory tracking modes. The normalized residual criterion is used as a one-step analytical tool to encompass the processes of identification, estimation, and diagnostic checking. A parameter constraining technique is introduced to develop more reliable models of human operator dynamics. The human operator is adequately modeled by a second order dynamic system both in pursuit and compensatory tracking modes. In comparing the data sampling rates, 100 msec between samples is adequate and is shown to provide better results than 200 msec sampling. The residual power spectrum and eigenvalue analysis show that the human operator is not a generator of periodic characteristics.

Quantum arrival times and operator normalization

International Nuclear Information System (INIS)

Hegerfeldt, Gerhard C.; Seidel, Dirk; Gonzalo Muga, J.

2003-01-01

A recent approach to arrival times used the fluorescence of an atom entering a laser illuminated region, and the resulting arrival-time distribution was close to the axiomatic distribution of Kijowski, but not exactly equal, neither in limiting cases nor after compensation of reflection losses by normalization on the level of expectation values. In this paper we employ a normalization on the level of operators, recently proposed in a slightly different context. We show that in this case the axiomatic arrival-time distribution of Kijowski is recovered as a limiting case. In addition, it is shown that Allcock's complex potential model is also a limit of the physically motivated fluorescence approach and connected to Kijowski's distribution through operator normalization

An assessment of the quality indicators of operative and non-operative times in a public university hospital.

Science.gov (United States)

Costa, Altair da Silva; Leão, Luiz Eduardo Villaça; Novais, Maykon Anderson Pires de; Zucchi, Paola

2015-01-01

To assess the operative time indicators in a public university hospital. A descriptive cross-sectional study was conducted using data from operating room database. The sample was obtained from January 2011 to January 2012. The operations performed in sequence in the same operating room, between 7:00 am and 5:00 pm, elective or emergency, were included. The procedures with incomplete data in the system were excluded, as well as the operations performed after 5:00 pm or on weekends or holidays. We measured the operative and non-operative time of 8,420 operations. The operative time (mean and standard deviation) of anesthesias and operations were 177.6 ± 110 and 129.8 ± 97.1 minutes, respectively. The total time of the patient in operative room (mean and standard deviation) was 196.8 ± 113.2. The non-operative time, e.g., between the arrival of the patient and the onset of anesthesia was 14.3 ± 17.3 minutes. The time to set the next patient in operating room was 119.8 ± 79.6 minutes. Our total non-operative time was 155 minutes. Delays frequently occurred in our operating room and had a major effect on patient flow and resource utilization. The non-operative time was longer than the operative time. It is possible to increase the operating room capacity by management and training of the professionals involved. The indicators provided a tool to improve operating room efficiency.

Impact of the European Working Time Directive (EWTD) on the operative experience of surgery residents.

Science.gov (United States)

Hopmans, Cornelis J; den Hoed, Pieter T; van der Laan, Lijckle; van der Harst, Erwin; van der Elst, Maarten; Mannaerts, Guido H H; Dawson, Imro; Timman, Reinier; Wijnhoven, Bas P L; IJzermans, Jan N M

2015-04-01

In Europe and the United States, work hour restrictions are considered to be particularly burdensome for residents in surgery specialties. The aim of this study was to examine whether reduction of the work week to 48 hours resulting from the implementation of the European Working Time Directive has affected the operative experience of surgery residents. This study was conducted in a general surgery training region in the Netherlands, consisting of 1 university hospital and 6 district training hospitals. Operating records summarizing the surgical procedures performed as "primary surgeon" in the operating theater for different grades of surgeons were retrospectively analyzed for the period 2005-2012 by the use of linear regression models. Operative procedures performed by residents were considered the main outcome measure. In total, 235,357 operative procedures were performed, including 47,458 (20.2%) in the university hospital and 187,899 (79.8%) in the district training hospitals (n = 5). For residents in the university hospital, the mean number of operative procedures performed per 1.0 full-time equivalent increased from 128 operations in 2005 to 204 operations in 2012 (P = .001), whereas for residents in district training hospitals, no substantial differences were found over time. The mean (±SD) operative caseload of 64 residents who completed the 6-year training program between 2005 and 2012 was 1,391 ± 226 (range, 768-1856). A comparison of the operative caseload according to year of board-certification showed no difference. Implementation of the European Working Time Directive has not affected adversely the number of surgical procedures performed by residents within a general surgical training region in the Netherlands. Copyright © 2015 Elsevier Inc. All rights reserved.

On the spectrum of a periodic operator with a small localized perturbation

International Nuclear Information System (INIS)

Borisov, D I; Gadyl'shin, R R

2008-01-01

The paper deals with the spectrum of a periodic self-adjoint differential operator on the real axis perturbed by a small localized non-self-adjoint operator. We show that the continuous spectrum does not depend on the perturbation, the residual spectrum is empty, and the point spectrum has no finite accumulation points. We study the problem of the existence of eigenvalues embedded in the continuous spectrum, obtain necessary and sufficient conditions for the existence of eigenvalues, construct asymptotic expansions of the eigenvalues and corresponding eigenfunctions and consider some examples

Smith predictor-based multiple periodic disturbance compensation for long dead-time processes

Science.gov (United States)

Tan, Fang; Li, Han-Xiong; Shen, Ping

2018-05-01

Many disturbance rejection methods have been proposed for processes with dead-time, while these existing methods may not work well under multiple periodic disturbances. In this paper, a multiple periodic disturbance rejection is proposed under the Smith predictor configuration for processes with long dead-time. One feedback loop is added to compensate periodic disturbance while retaining the advantage of the Smith predictor. With information of the disturbance spectrum, the added feedback loop can remove multiple periodic disturbances effectively. The robust stability can be easily maintained through the rigorous analysis. Finally, simulation examples demonstrate the effectiveness and robustness of the proposed method for processes with long dead-time.

Period, epoch, and prediction errors of ephemerides from continuous sets of timing measurements

Science.gov (United States)

Deeg, H. J.

2015-06-01

Space missions such as Kepler and CoRoT have led to large numbers of eclipse or transit measurements in nearly continuous time series. This paper shows how to obtain the period error in such measurements from a basic linear least-squares fit, and how to correctly derive the timing error in the prediction of future transit or eclipse events. Assuming strict periodicity, a formula for the period error of these time series is derived, σP = σT (12 / (N3-N))1 / 2, where σP is the period error, σT the timing error of a single measurement, and N the number of measurements. Compared to the iterative method for period error estimation by Mighell & Plavchan (2013), this much simpler formula leads to smaller period errors, whose correctness has been verified through simulations. For the prediction of times of future periodic events, usual linear ephemeris were epoch errors are quoted for the first time measurement, are prone to an overestimation of the error of that prediction. This may be avoided by a correction for the duration of the time series. An alternative is the derivation of ephemerides whose reference epoch and epoch error are given for the centre of the time series. For long continuous or near-continuous time series whose acquisition is completed, such central epochs should be the preferred way for the quotation of linear ephemerides. While this work was motivated from the analysis of eclipse timing measures in space-based light curves, it should be applicable to any other problem with an uninterrupted sequence of discrete timings for which the determination of a zero point, of a constant period and of the associated errors is needed.

Comparison of laparoscopic and open appendectomy in terms of operative time, hospital stay and frequency of surgical site infection

International Nuclear Information System (INIS)

Ibrahim, T.; Saleem, M.R.; Aziz, O.B.; Arshad, A.

2014-01-01

To compare laparoscopic and conventional open appendectomy in terms of operative time, hospital stay and frequency of surgical site infection (SSI). Patient and Methods: A total of 417 patients underwent appendectomy during this period. 137 patients underwent laparoscopic appendectomy (group A) while 280 patient had open appendectomy (group B). The samples include all patients who were operated open between the time span of june 2010 to september 2011. A chi square-test was performed to compare the data for statistical significance. Result: Mean operative time for group A was 79.21+-23.42 minitues where as in group B, the mean operative time was 41.49+-20.86 minitues. Group A patients had a shorter hospital 1 stay (3.6+-1 day) but in group B it was (5.2+-3 days). Seven patients (5.1 %) developed surgical site infection (SSI) in group A and 34 patients (12.14 %)developed postoperative SSI in group B. Conclusion: Laparoscopic appendectomy is superior to open appendectomy because of shorter hospital stay and laser-operative SSI, but requires longer operative time. (author)

Mixed-mode Operating System for Real-time Performance

OpenAIRE

M.M. Hasan; S. Sultana; C.K. Foo

2017-01-01

The purpose of the mixed-mode system research is to handle devices with the accuracy of real-time systems and at the same time, having all the benefits and facilities of a matured Graphic User Interface (GUI) operating system which is typically nonreal-time. This mixed-mode operating system comprising of a real-time portion and a non-real-time portion was studied and implemented to identify the feasibilities and performances in practical applications (in the context of scheduled the real-time...

Mixed - mode Operating System for Real - time Performance

OpenAIRE

Hasan M. M.; Sultana S.; Foo C.K.

2017-01-01

The purpose of the mixed-mode system research is to handle devices with the accuracy of real-time systems and at the same time, having all the benefits and facilities of a matured Graphic User Interface(GUI)operating system which is typicallynon-real-time. This mixed-mode operating system comprising of a real-time portion and a non-real-time portion was studied and implemented to identify the feasibilities and performances in practical applications (in the context of scheduled the real-time e...

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)

Adiabatic theorem for the time-dependent wave operator

International Nuclear Information System (INIS)

Viennot, David; Jolicard, Georges; Killingbeck, John P.; Perrin, Marie-Yvonne

2005-01-01

The application of time-dependent wave operator theory to the development of a quantum adiabatic perturbation theory is treated both theoretically and numerically, with emphasis on the description of field-matter interactions which involve short laser pulses. It is first shown that the adiabatic limit of the time-dependent wave operator corresponds to a succession of instantaneous static Bloch wave operators. Wave operator theory is then shown to be compatible with the two-time Floquet theory of light-matter interaction, thus allowing the application of Floquet theory to cases which require the use of a degenerate active space. A numerical study of some problems shows that the perturbation strength associated with nonadiabatic processes can be reduced by using multidimensional active spaces and illustrates the capacity of the wave operator approach to produce a quasiadiabatic treatment of a nominally nonadiabatic Floquet dynamical system

"Knife to skin" time is a poor marker of operating room utilization and efficiency in cardiac surgery.

Science.gov (United States)

Luthra, Suvitesh; Ramady, Omar; Monge, Mary; Fitzsimons, Michael G; Kaleta, Terry R; Sundt, Thoralf M

2015-06-01

Markers of operation room (OR) efficiency in cardiac surgery are focused on "knife to skin" and "start time tardiness." These do not evaluate the middle and later parts of the cardiac surgical pathway. The purpose of this analysis was to evaluate knife to skin time as an efficiency marker in cardiac surgery. We looked at knife to skin time, procedure time, and transfer times in the cardiac operational pathway for their correlation with predefined indices of operational efficiency (Index of Operation Efficiency - InOE, Surgical Index of Operational Efficiency - sInOE). A regression analysis was performed to test the goodness of fit of the regression curves estimated for InOE relative to the times on the operational pathway. The mean knife to skin time was 90.6 ± 13 minutes (23% of total OR time). The mean procedure time was 282 ± 123 minutes (71% of total OR time). Utilization efficiencies were highest for aortic valve replacement and coronary artery bypass grafting and least for complex aortic procedures. There were no significant procedure-specific or team-specific differences for standard procedures. Procedure times correlated the strongest with InOE (r = -0.98, p knife to skin is not as strong an indicator of efficiency. A statistically significant linear dependence on InOE was observed with "procedure times" only. Procedure times are a better marker of OR efficiency than knife to skin in cardiac cases. Strategies to increase OR utilization and efficiency should address procedure times in addition to knife to skin times. © 2015 Wiley Periodicals, Inc.

Period doubling phenomenon in a class of time delay equations

International Nuclear Information System (INIS)

Oliveira, C.R. de; Malta, C.P.

1985-01-01

The properties of the solution of a nonlinear time delayed differential equation (infinite dimension) as function of two parameters: the time delay tau and another parameter A (nonlinearity) are investigated. After a Hopf bifurcation period doubling may occur and is characterized by Feigenbaum's delta. A strange atractor is obtained after the period doubling cascade and the largest Lyapunov exponent is calculated indicating that the attractor has low dimension. The behaviour of this Liapunov exponent as function of tau is different from its behaviour as function of A. (Author) [pt

Spectrum of three-dimensional Landau operator perturbed by a periodic point potential

International Nuclear Information System (INIS)

Geiler, V.A.; Demidov, V.V.

1995-01-01

A study is made of a three-dimensional Schrodinger operator with magnetic field and perturbed by a periodic sum of zero-range potentials. In the case of a rational flux, the explicit form of the decomposition of the resolvent of this operator with respect to the spectrum of irreducible representations of the group of magnetic translations is found. In the case of integer flux, the explicit form of the dispersion laws is found, the spectrum is described, and a qualitative investigation of it is made (in particular, it is established that not more than one gap exists)

Optimizing capital and time expenditures for drilling service operations

Energy Technology Data Exchange (ETDEWEB)

Zazovskiy, F Ya; Soltysyak, T I

1980-01-01

The operational efficiency of drilling services operations management are examined. The structure of time expenditure is analyzed for repair operations according to equipment type employed by the Ivano-Frankovsk Drilling Management under the Ukrneft' enterprise during 1977. The results of this analysis are weighed against a series of service operations carried out at industrial enterprises and connected with technical disruptions. Some of the cases examined include service competion operations outside of the industrial units when technical processes are disrupted only for the change of equipment which has outlived its usefulness and is no longer in series production. First of all, time expended for repair work can be reduced to zero during the drilling of shallow wells which do not require extensive drilling time. The actual savings, both in time and money, as far as repair work is concerned, hinges on the actual time factor for total oil depetion. An equation is provided for optimal time expenditure necessary for repair work and equipment replacement. An actual example is given from the Dolinsk UBR (Drillin Management) under the Ukrneft' enterprise where time spent on actual service operations has appeared to be less than the optimal figure cited in the above material. This is possible because of increased capital expenditures.

Finding hidden periodic signals in time series - an application to stock prices

Science.gov (United States)

O'Shea, Michael

2014-03-01

Data in the form of time series appear in many areas of science. In cases where the periodicity is apparent and the only other contribution to the time series is stochastic in origin, the data can be `folded' to improve signal to noise and this has been done for light curves of variable stars with the folding resulting in a cleaner light curve signal. Stock index prices versus time are classic examples of time series. Repeating patterns have been claimed by many workers and include unusually large returns on small-cap stocks during the month of January, and small returns on the Dow Jones Industrial average (DJIA) in the months June through September compared to the rest of the year. Such observations imply that these prices have a periodic component. We investigate this for the DJIA. If such a component exists it is hidden in a large non-periodic variation and a large stochastic variation. We show how to extract this periodic component and for the first time reveal its yearly (averaged) shape. This periodic component leads directly to the `Sell in May and buy at Halloween' adage. We also drill down and show that this yearly variation emerges from approximately half of the underlying stocks making up the DJIA index.

Life time calculations for LCF loading combined with tensional hold periods

International Nuclear Information System (INIS)

Bocek, M.; Armas, A.; Piel, D.

1983-01-01

The life time in high amplitude strain cycling with tensional hold periods is analysed presuming that creep failure damage is life determining. The life fraction rule (LFR) is used to calculate the life time consumpted during the dwell period in strain controlled tests as well as during tensional hold time stress cycles. It follows from the present investigation that stress relaxation occurring during the strain hold periods plays the dominant influence upon the relationship between life and dwell time. For strong stress relaxation (e.g. high temperature) less damage is accumulated as compared to suppressed relaxation (low temperature). The damage in stress relaxation is calculated by means of the LFR and the results are compared to experiments conducted on Zircaloy-4 and the austenitic stainless stell Type AISI 304. From the very good agreement between both it is concluded that under the loading conditions considered, creep failure damage is the main life determining damage contribution. (orig.)

Summary of the CDFE nuclear data activity for 2011 - 2012 period of time, Progress report

International Nuclear Information System (INIS)

Varlamov, V.V.; Komarov, S.Yu.; Peskov, N.N.; Stepanov, M.E.

2012-01-01

This report contains the short review of the main fields of nuclear data activity of the Centre for Photonuclear Experiments Data (Centr Dannykh Fotoyadernykh Eksperimentov - CDFE) of Skobeltsyn Institute of Nuclear Physics of Lomonosov Moscow State University and main results obtained. All works were carried out in close co-operation with the Nuclear Science Section in the frame of the IAEA Nuclear Reaction Data Centres Network for the period of time from the IAEA Technical Meeting on the International Network of Nuclear Reaction Data Centers' (23 - 24 May 2011, IAEA, Vienna, Austria) till the spring of 2012. (author)

Transient habitats limit development time for periodical cicadas.

Science.gov (United States)

Karban, Richard

2014-01-01

Periodical cicadas (Magicicada spp.) mature in 13 or 17 years, the longest development times for any non-diapausing insects. Selection may favor prolonged development since nymphs experience little mortality and individuals taking 17 years have been shown to have greater fecundity than those taking 13 years. Why don't periodical cicadas take even longer to develop? Nymphs feed on root xylem fluid and move little. Ovipositing females prefer fast-growing trees at forest edges. I hypothesized that (1) adults emerging at edges would be heavier than those from forest interiors and (2) habitat changes could limit development time. I collected newly eclosed females that had neither fed as adults nor moved from their site of development. For M. septendecim, females from edges were 4.9% heavier than those from the interior. I assumed that emergence density indicated habitat quality and measured density at eight sites in 1979, 1996, and 2013. Over three generations, variation in densities was great; densities at two sites crashed, and at one site they exploded to 579/m2 Habitat transience may limit development time because only adults can reassess habitats and reposition offspring. In conclusion, cicadas are affected by habitat characteristics, habitats change over 17 years, and cicadas may emerge, mate, and redistribute their offspring to track habitat dynamics.

Remaining useful life estimation for deteriorating systems with time-varying operational conditions and condition-specific failure zones

Directory of Open Access Journals (Sweden)

Li Qi

2016-06-01

Full Text Available Dynamic time-varying operational conditions pose great challenge to the estimation of system remaining useful life (RUL for the deteriorating systems. This paper presents a method based on probabilistic and stochastic approaches to estimate system RUL for periodically monitored degradation processes with dynamic time-varying operational conditions and condition-specific failure zones. The method assumes that the degradation rate is influenced by specific operational condition and moreover, the transition between different operational conditions plays the most important role in affecting the degradation process. These operational conditions are assumed to evolve as a discrete-time Markov chain (DTMC. The failure thresholds are also determined by specific operational conditions and described as different failure zones. The 2008 PHM Conference Challenge Data is utilized to illustrate our method, which contains mass sensory signals related to the degradation process of a commercial turbofan engine. The RUL estimation method using the sensor measurements of a single sensor was first developed, and then multiple vital sensors were selected through a particular optimization procedure in order to increase the prediction accuracy. The effectiveness and advantages of the proposed method are presented in a comparison with existing methods for the same dataset.

Start time delays in operating room: Different perspectives

Directory of Open Access Journals (Sweden)

Babita Gupta

2011-01-01

Full Text Available Background: Healthcare expenditure is a serious concern, with escalating costs failing to meet the expectations of quality care. The treatment capacities are limited in a hospital setting and the operating rooms (ORs. Their optimal utilization is vital in efficient hospital management. Starting late means considerable wait time for staff, patients and waste of resources. We planned an audit to assess different perspectives of the residents in surgical specialities and anesthesia and OR staff nurses so as to know the causative factors of operative delay. This can help develop a practical model to decrease start time delays in operating room (ORs. Aims: An audit to assess different perspectives of the Operating room (OR staff with respect to the varied causative factors of operative delay in the OR. To aid in the development of a practical model to decrease start time delays in ORs and facilitate on-time starts at Jai Prakash Narayan Apex Trauma centre (JPNATC, All India Institute of Medical Sciences (AIIMS, New Delhi. Methods: We prepared a questionnaire seeking the five main reasons of delay as per their perspective. Results: The available data was analysed. Analysis of the data demonstrated the common causative factors in start time operative delays as: a lack of proper planning, deficiencies in team work, communication gap and limited availability of trained supporting staff. Conclusions: The preparation of the equipment and required material for the OR cases must be done well in advance. Utilization of newer technology enables timely booking and scheduling of cases. Improved inter-departmental coordination and compliance with preanesthetic instructions needs to be ensured. It is essential that the anesthesiologists perform their work promptly, well in time . and supervise the proceedings as the OR manager. This audit is a step forward in defining the need of effective OR planning for continuous quality improvement.

Real-time Testing of Operating Systems on Raspberry Pi

OpenAIRE

Murstad, Amund

2016-01-01

A subset of operating systems are called ``real time'' operating systems. While a general operating system like Windows or OSX can make no guarantee when a process gets to run, a real time one has the ability to do so. They are used for systems where the quality of the results from the operating system is not only defined by their correctness, but also by when they arrive. These kinds of systems are called Real-time Systems and can be divided into soft, hard and firm. If a deadline is missed ...

A Time-Composable Operating System for the Patmos Processor

DEFF Research Database (Denmark)

Ziccardi, Marco; Schoeberl, Martin; Vardanega, Tullio

2015-01-01

-composable operating system, on top of a time-composable processor, facilitates incremental development, which is highly desirable for industry. This paper makes a twofold contribution. First, we present enhancements to the Patmos processor to allow achieving time composability at the operating system level. Second......, we extend an existing time-composable operating system, TiCOS, to make best use of advanced Patmos hardware features in the pursuit of time composability.......In the last couple of decades we have witnessed a steady growth in the complexity and widespread of real-time systems. In order to master the rising complexity in the timing behaviour of those systems, rightful attention has been given to the development of time-predictable computer architectures...

Using travel times to simulate multi-dimensional bioreactive transport in time-periodic flows.

Science.gov (United States)

Sanz-Prat, Alicia; Lu, Chuanhe; Finkel, Michael; Cirpka, Olaf A

2016-04-01

In travel-time models, the spatially explicit description of reactive transport is replaced by associating reactive-species concentrations with the travel time or groundwater age at all locations. These models have been shown adequate for reactive transport in river-bank filtration under steady-state flow conditions. Dynamic hydrological conditions, however, can lead to fluctuations of infiltration velocities, putting the validity of travel-time models into question. In transient flow, the local travel-time distributions change with time. We show that a modified version of travel-time based reactive transport models is valid if only the magnitude of the velocity fluctuates, whereas its spatial orientation remains constant. We simulate nonlinear, one-dimensional, bioreactive transport involving oxygen, nitrate, dissolved organic carbon, aerobic and denitrifying bacteria, considering periodic fluctuations of velocity. These fluctuations make the bioreactive system pulsate: The aerobic zone decreases at times of low velocity and increases at those of high velocity. For the case of diurnal fluctuations, the biomass concentrations cannot follow the hydrological fluctuations and a transition zone containing both aerobic and obligatory denitrifying bacteria is established, whereas a clear separation of the two types of bacteria prevails in the case of seasonal velocity fluctuations. We map the 1-D results to a heterogeneous, two-dimensional domain by means of the mean groundwater age for steady-state flow in both domains. The mapped results are compared to simulation results of spatially explicit, two-dimensional, advective-dispersive-bioreactive transport subject to the same relative fluctuations of velocity as in the one-dimensional model. The agreement between the mapped 1-D and the explicit 2-D results is excellent. We conclude that travel-time models of nonlinear bioreactive transport are adequate in systems of time-periodic flow if the flow direction does not change

Time Warp Operating System, Version 2.5.1

Science.gov (United States)

Bellenot, Steven F.; Gieselman, John S.; Hawley, Lawrence R.; Peterson, Judy; Presley, Matthew T.; Reiher, Peter L.; Springer, Paul L.; Tupman, John R.; Wedel, John J., Jr.; Wieland, Frederick P.;

19 CFR 351.524 - Allocation of benefit to a particular time period.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 3 2010-04-01 2010-04-01 false Allocation of benefit to a particular time period. 351.524 Section 351.524 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE... Allocation of benefit to a particular time period. Unless otherwise specified in §§ 351.504-351.523, the...

Generation of a quantum integrable class of discrete-time or relativistic periodic Toda chains

International Nuclear Information System (INIS)

Kundu, Anjan

1994-01-01

A new integrable class of quantum models representing a family of different discrete-time or relativistic generalisations of the periodic Toda chain (TC), including that of a recently proposed classical model close to TC [Lett. Math. Phys. 29 (1993) 165] is presented. All such models are shown to be obtainable from a single ancestor model at different realisations of the underlying quantised algebra. As a consequence the 2x2 Lax operators and the associated quantum R-matrices for these models are easily derived ensuring their quantum integrability. It is shown that the functional Bethe ansatz developed for the quantum TC is trivially generalised to achieve separation of variables also for the present models. ((orig.))

Hydraulic residence time and iron removal in a wetland receiving ferruginous mine water over a 4 year period from commissioning.

Science.gov (United States)

Kusin, F M; Jarvis, A P; Gandy, C J

2010-01-01

Analysis of residence time distribution (RTD) has been conducted for the UK Coal Authority's mine water treatment wetland at Lambley, Northumberland, to determine the hydraulic performance of the wetland over a period of approximately 4 years since site commissioning. The wetland RTD was evaluated in accordance with moment analysis and modelled based on a tanks-in-series (TIS) model to yield the hydraulic characteristics of system performance. Greater hydraulic performance was seen during the second site monitoring after 21 months of site operation i.e. longer hydraulic residence time to reflect overall system hydraulic efficiency, compared to wetland performance during its early operation. Further monitoring of residence time during the third year of wetland operation indicated a slight reduction in hydraulic residence time, thus a lower system hydraulic efficiency. In contrast, performance during the fourth year of wetland operation exhibited an improved overall system hydraulic efficiency, suggesting the influence of reed growth over the lifetime of such systems on hydraulic performance. Interestingly, the same pattern was found for iron (which is the primary pollutant of concern in ferruginous mine waters) removal efficiency of the wetland system from the second to fourth year of wetland operation. This may therefore, reflect the maturity of reeds for maintaining efficient flow distribution across the wetland to retain a longer residence time and significant fractions of water involved to enhance the extent of treatment received for iron attenuation. Further monitoring will be conducted to establish whether such performance is maintained, or whether efficiency decreases over time due to accumulation of dead plant material within the wetland cells.

Smooth time-dependent receiver operating characteristic curve estimators.

Science.gov (United States)

Martínez-Camblor, Pablo; Pardo-Fernández, Juan Carlos

2018-03-01

The receiver operating characteristic curve is a popular graphical method often used to study the diagnostic capacity of continuous (bio)markers. When the considered outcome is a time-dependent variable, two main extensions have been proposed: the cumulative/dynamic receiver operating characteristic curve and the incident/dynamic receiver operating characteristic curve. In both cases, the main problem for developing appropriate estimators is the estimation of the joint distribution of the variables time-to-event and marker. As usual, different approximations lead to different estimators. In this article, the authors explore the use of a bivariate kernel density estimator which accounts for censored observations in the sample and produces smooth estimators of the time-dependent receiver operating characteristic curves. The performance of the resulting cumulative/dynamic and incident/dynamic receiver operating characteristic curves is studied by means of Monte Carlo simulations. Additionally, the influence of the choice of the required smoothing parameters is explored. Finally, two real-applications are considered. An R package is also provided as a complement to this article.

Structure and dating errors in the geologic time scale and periodicity in mass extinctions

Science.gov (United States)

Stothers, Richard B.

1989-01-01

Structure in the geologic time scale reflects a partly paleontological origin. As a result, ages of Cenozoic and Mesozoic stage boundaries exhibit a weak 28-Myr periodicity that is similar to the strong 26-Myr periodicity detected in mass extinctions of marine life by Raup and Sepkoski. Radiometric dating errors in the geologic time scale, to which the mass extinctions are stratigraphically tied, do not necessarily lessen the likelihood of a significant periodicity in mass extinctions, but do spread the acceptable values of the period over the range 25-27 Myr for the Harland et al. time scale or 25-30 Myr for the DNAG time scale. If the Odin time scale is adopted, acceptable periods fall between 24 and 33 Myr, but are not robust against dating errors. Some indirect evidence from independently-dated flood-basalt volcanic horizons tends to favor the Odin time scale.

Operator support systems in NPPs. Summary of the activities in the period 1993-1995

International Nuclear Information System (INIS)

Silvani, V.

1996-01-01

The report presents an overview of major activities performed in ENEA and ANPA in the period 1993-1995 related to CRP subject. Being in Italy the Nuclear Power Plant not in operation since 1987, studied and research under development related to the CRP subject make reference to technological themes such as the methods to improve the software quality in critical application and the methods to improve the operator training. (author). 5 refs

On Real-Time Operating Systems.

Science.gov (United States)

1987-04-01

1Ri2 193 ONREAL-TIME OPERATING SYS EMS(U MAYLAN UN V COLLG PARK DEPT OF COMPUTER SCIENCE S LEVI ET AL APR 87 CS-TR-1838 NOSO14-87-K-9124 UNCLASSIFIED...and processes. In each instance the abstraction takes the form of some non- physical resource and benefits both the system and the user. ...The...service, which is important as an inter-process service (for physical synchronization) as well as an internal service for a process. A time service in a

The relaxation of the operation restrictions at typhoon period for Taipower's nuclear power plant

International Nuclear Information System (INIS)

Wang, L.C.; Chou, L.Y.

2004-01-01

This paper analyzes the station blackout event for Taipower's nuclear power plant and proposes a plan whereby the availability of the plant at typhoon period can be increased through a systematic approach to improvements in the old operating restrictions. The conclusions have shown that the old operating restrictions were too strict and can be relaxed without increasing the likelihood of core damage or core melt for the accident sequence. After a detailed review of this analysis report, Republic of China Atomic Energy Commission (ROCAEC) has approved the relaxation of the operating restrictions as proposed by Taiwan Power Company. (author)

Surgical team turnover and operative time: An evaluation of operating room efficiency during pulmonary resection.

Science.gov (United States)

Azzi, Alain Joe; Shah, Karan; Seely, Andrew; Villeneuve, James Patrick; Sundaresan, Sudhir R; Shamji, Farid M; Maziak, Donna E; Gilbert, Sebastien

2016-05-01

Health care resources are costly and should be used judiciously and efficiently. Predicting the duration of surgical procedures is key to optimizing operating room resources. Our objective was to identify factors influencing operative time, particularly surgical team turnover. We performed a single-institution, retrospective review of lobectomy operations. Univariate and multivariate analyses were performed to evaluate the impact of different factors on surgical time (skin-to-skin) and total procedure time. Staff turnover within the nursing component of the surgical team was defined as the number of instances any nurse had to leave the operating room over the total number of nurses involved in the operation. A total of 235 lobectomies were performed by 5 surgeons, most commonly for lung cancer (95%). On multivariate analysis, percent forced expiratory volume in 1 second, surgical approach, and lesion size had a significant effect on surgical time. Nursing turnover was associated with a significant increase in surgical time (53.7 minutes; 95% confidence interval, 6.4-101; P = .026) and total procedure time (83.2 minutes; 95% confidence interval, 30.1-136.2; P = .002). Active management of surgical team turnover may be an opportunity to improve operating room efficiency when the surgical team is engaged in a major pulmonary resection. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Periodically driven random quantum spin chains: real-space renormalization for Floquet localized phases

Science.gov (United States)

Monthus, Cécile

2017-07-01

When random quantum spin chains are submitted to some periodic Floquet driving, the eigenstates of the time-evolution operator over one period can be localized in real space. For the case of periodic quenches between two Hamiltonians (or periodic kicks), where the time-evolution operator over one period reduces to the product of two simple transfer matrices, we propose a block-self-dual renormalization procedure to construct the localized eigenstates of the Floquet dynamics. We also discuss the corresponding strong disorder renormalization procedure, that generalizes the RSRG-X procedure to construct the localized eigenstates of time-independent Hamiltonians.

Depression in the US population during the time periods surrounding the great recession.

Science.gov (United States)

Mehta, Kaushal; Kramer, Holly; Durazo-Arvizu, Ramon; Cao, Guichan; Tong, Liping; Rao, Murali

2015-04-01

To determine whether the time periods surrounding the 2008 US economic downturn were accompanied by an increase in prevalence of depression in the US adult population. We used data from the 24,182 adults aged ≥ 18 years who participated in the National Health and Nutrition Examination Survey during 2005-2012. A cross-sectional analysis was performed at each time period to determine prevalence of major and other depression as assessed by standardized questionnaires based on 9 criteria for major depressive episodes defined by DSM-IV. The demographic characteristics of the US population were similar across time periods except for the percentage of adults living in poverty, which increased from 26.43% during 2005-2006 to 33.46% during 2011-2012. The prevalence of major depression increased from 2.33% (95% CI, 1.64%-3.01%) during 2005-2006 to 3.49% (95% CI, 2.84%-4.03%) in 2009-2010 to 3.79% (95% CI, 3.01%-4.57%) in 2011-2012. Prevalence of other depression increased from 4.10% (95% CI, 3.37%-4.88%) in 2005-2006 to 4.79% (95% CI, 4.10%-5.44%) in the 2009-2010 period but then declined to 3.68% (95% CI, 2.84%-4.48%) in the 2011-2012 time period (P = .4). After adjustment for the distribution of age, sex, race/ethnicity, education, insurance status, and poverty status in the US adult noninstitutionalized population, each 2-year period after the 2005-2006 time period was associated with a 0.4% increase in major depression prevalence (P depression prevalence were noted by time period (P = .6). The time periods surrounding the recent economic recession were accompanied by a significant and sustained increase in major depression prevalence in the US population. It is plausible that the recession, given its strong, persistent, and negative effects on employment, job and housing security, and stock investments, contributed to the sustained increase in prevalence of major depression in the US population, but other factors associated with the recession time period could have

Impact of an electronic health record operating room management system in ophthalmology on documentation time, surgical volume, and staffing.

Science.gov (United States)

Sanders, David S; Read-Brown, Sarah; Tu, Daniel C; Lambert, William E; Choi, Dongseok; Almario, Bella M; Yackel, Thomas R; Brown, Anna S; Chiang, Michael F

2014-05-01

Although electronic health record (EHR) systems have potential benefits, such as improved safety and quality of care, most ophthalmology practices in the United States have not adopted these systems. Concerns persist regarding potential negative impacts on clinical workflow. In particular, the impact of EHR operating room (OR) management systems on clinical efficiency in the ophthalmic surgery setting is unknown. To determine the impact of an EHR OR management system on intraoperative nursing documentation time, surgical volume, and staffing requirements. For documentation time and circulating nurses per procedure, a prospective cohort design was used between January 10, 2012, and January 10, 2013. For surgical volume and overall staffing requirements, a case series design was used between January 29, 2011, and January 28, 2013. This study involved ophthalmic OR nurses (n = 13) and surgeons (n = 25) at an academic medical center. Electronic health record OR management system implementation. (1) Documentation time (percentage of operating time documenting [POTD], absolute documentation time in minutes), (2) surgical volume (procedures/time), and (3) staffing requirements (full-time equivalents, circulating nurses/procedure). Outcomes were measured during a baseline period when paper documentation was used and during the early (first 3 months) and late (4-12 months) periods after EHR implementation. There was a worsening in total POTD in the early EHR period (83%) vs paper baseline (41%) (P system implementation was associated with worsening of intraoperative nursing documentation time especially in shorter procedures. However, it is possible to implement an EHR OR management system without serious negative impacts on surgical volume and staffing requirements.

Real-Time Operating Systems for Multicore Embedded Systems

OpenAIRE

Tomiyama, Hiroyuki; Honda, Shinya; Takada, Hiroaki

2008-01-01

Multicore systems-on-chip have become popular inthe design of embedded systems in order to simultaneously achieve high performance and low power consumption. On the software side, real-time operating systems are necessary in orderto handle growing complexity of embedded software. This paper describes requirements, design principles and implementation techniques for real-time operating systems to be used inasymmetric multicore systems.

Decisiveness of the spectral gaps of periodic Schrödinger operators on the dumbbell-like metric graph

Directory of Open Access Journals (Sweden)

Hiroaki Niikuni

2015-01-01

Full Text Available In this paper, we consider periodic Schrödinger operators on the dumbbell-like metric graph, which is a periodic graph consisting of lines and rings. Let one line and two rings be in the basic period. We see the relationship between the structure of graph and the band-gap spectrum.

Theory of many-body localization in periodically driven systems

International Nuclear Information System (INIS)

Abanin, Dmitry A.; De Roeck, Wojciech; Huveneers, François

2016-01-01

We present a theory of periodically driven, many-body localized (MBL) systems. We argue that MBL persists under periodic driving at high enough driving frequency: The Floquet operator (evolution operator over one driving period) can be represented as an exponential of an effective time-independent Hamiltonian, which is a sum of quasi-local terms and is itself fully MBL. We derive this result by constructing a sequence of canonical transformations to remove the time-dependence from the original Hamiltonian. When the driving evolves smoothly in time, the theory can be sharpened by estimating the probability of adiabatic Landau–Zener transitions at many-body level crossings. In all cases, we argue that there is delocalization at sufficiently low frequency. We propose a phase diagram of driven MBL systems.

An Estimation of Operator's Diagnostic Time for Feed-And-Bleed Operation under Various Scenarios

Energy Technology Data Exchange (ETDEWEB)

Kim, Bo Gyung; Kang, Hyun Gook [KAIST, Daejeon (Korea, Republic of); Yoon, Ho Joon [Khalifa University of Science, Abu Dhabi (United Arab Emirates)

2015-10-15

In order to assess realistic safety of plant, effects of interactions between components, operator, and plant condition are needed to be considered in the PSA model. One of the important issues to estimate the CDF is the estimation of human error probability (HEP). When an accident occurs, operators follow the emergency operating procedure and check various alarm, parameters, and signals. In the conventional Korean PSA model, the Korean standard HRA (K-HRA) method is used. In this method, the HEP is the sum of diagnosis error probability and execution error probability. A diagnosis error probability is expressed by the available time for diagnosis and adjusting performance shaping factors, and an execution error probability is a function of task type and stress level. Available time for diagnosis is very important factor of HEP. If the available time for diagnosis is short, the HEP becomes high. In order to obtain the realistic risk assessment results, we first focus on the estimation of HEP considering the plant dynamics under various scenarios. Target operation and scenarios are feed-and bleed operation (F and B operation) and total loss of feedwater (TLOFW) accident with/without loss of coolant accident (LOCA). One of the highest HEP is HEP of FnB operation. In additional, Scenarios, which are related to combination secondary heat removal failure and primary heat removal failure, are most critical core damage scenario of the combined accident except scenarios related to station black out (SBO). In these scenarios, the FnB operation is last resort to prevent core damage. To estimate available operator diagnosis time, we identify the relationship between accidents, mitigation function, and plant condition. Distribution of available time of diagnosis was estimated using the MOSAIQUE. The variables are break size, break timing, trip timing of RCP, and availability of high pressure safety injection (HPSI) pump under the TLOFW accident with LOCA. For Type 1 accident

Overview of real-time operating systems on microprocessor platforms

International Nuclear Information System (INIS)

Luong, T.T.

1994-01-01

This paper attempts to overview the real-time operating systems on microprocessor platforms in the field of experimental physics facility controls. The key issues regarding operating systems as well as standards and development environment are discussed. As an illustration, some current industrial products are indicated. Also, real-time systems operating in some institutes of the EPS/EPCS inter divisional group are reviewed. (author). 3 refs., 4 figs

A distributed real-time operating system

International Nuclear Information System (INIS)

Tuynman, F.; Hertzberger, L.O.

1984-07-01

A distributed real-time operating system, Fados, has been developed for an embedded multi-processor system. The operating system is based on a host target approach and provides for communication between arbitrary processes on host and target machine. The facilities offered are, apart from process communication, access to the file system on the host by programs on the target machine and monitoring and debugging of programs on the target machine from the host. The process communication has been designed in such a way that the possibilities are the same as those offered by the Ada programming language. The operating system is implemented on a MC 68000 based multiprocessor system in combination with a Unix host. (orig.)

Existence of time-periodic weak solutions to the stochastic Navier-Stokes equations around a moving body

International Nuclear Information System (INIS)

Chen, Feng; Han, Yuecai

2013-01-01

The existence of time-periodic stochastic motions of an incompressible fluid is obtained. Here the fluid is subject to a time-periodic body force and an additional time-periodic stochastic force that is produced by a rigid body moves periodically stochastically with the same period in the fluid

Existence of time-periodic weak solutions to the stochastic Navier-Stokes equations around a moving body

Energy Technology Data Exchange (ETDEWEB)

Chen, Feng, E-mail: chenfengmath@163.com, E-mail: hanyc@jlu.edu.cn; Han, Yuecai, E-mail: chenfengmath@163.com, E-mail: hanyc@jlu.edu.cn [School of Mathematics, Jilin University, Changchun 130012 (China)

2013-12-15

The existence of time-periodic stochastic motions of an incompressible fluid is obtained. Here the fluid is subject to a time-periodic body force and an additional time-periodic stochastic force that is produced by a rigid body moves periodically stochastically with the same period in the fluid.

Effects of extended lay-off periods on performance and operator trust under adaptable automation.

Science.gov (United States)

Chavaillaz, Alain; Wastell, David; Sauer, Jürgen

2016-03-01

Little is known about the long-term effects of system reliability when operators do not use a system during an extended lay-off period. To examine threats to skill maintenance, 28 participants operated twice a simulation of a complex process control system for 2.5 h, with an 8-month retention interval between sessions. Operators were provided with an adaptable support system, which operated at one of the following reliability levels: 60%, 80% or 100%. Results showed that performance, workload, and trust remained stable at the second testing session, but operators lost self-confidence in their system management abilities. Finally, the effects of system reliability observed at the first testing session were largely found again at the second session. The findings overall suggest that adaptable automation may be a promising means to support operators in maintaining their performance at the second testing session. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Determining the Optimum Exposure and Recovery Periods for Efficient Operation of a QCM Based Elemental Mercury Vapor Sensor

Directory of Open Access Journals (Sweden)

K. M. Mohibul Kabir

2015-01-01

Full Text Available In recent years, mass based transducers such as quartz crystal microbalance (QCM have gained huge interest as potential sensors for online detection of elemental mercury (Hg0 vapor from anthropogenic sources due to their high portability and robust nature enabling them to withstand harsh industrial environments. In this study, we determined the optimal Hg0 exposure and recovery times of a QCM based sensor for ensuring its efficient operation while monitoring low concentrations of Hg0 vapor (<400 ppbv. The developed sensor was based on an AT-cut quartz substrate and utilized two gold (Au films on either side of the substrate which functions as the electrodes and selective layer simultaneously. Given the temporal response mechanisms associated with mass based mercury sensors, the experiments involved the variation of Hg0 vapor exposure periods while keeping the recovery time constant following each exposure and vice versa. The results indicated that an optimum exposure and recovery periods of 30 and 90 minutes, respectively, can be utilized to acquire the highest response magnitudes and recovery rate towards a certain concentration of Hg0 vapor whilst keeping the time it takes to report an accurate reading by the sensor to a minimum level as required in real-world applications.

Periodic safety analyses; Les essais periodiques

Energy Technology Data Exchange (ETDEWEB)

Gouffon, A; Zermizoglou, R

1990-12-01

The IAEA Safety Guide 50-SG-S8 devoted to 'Safety Aspects of Foundations of Nuclear Power Plants' indicates that operator of a NPP should establish a program for inspection of safe operation during construction, start-up and service life of the plant for obtaining data needed for estimating the life time of structures and components. At the same time the program should ensure that the safety margins are appropriate. Periodic safety analysis are an important part of the safety inspection program. Periodic safety reports is a method for testing the whole system or a part of the safety system following the precise criteria. Periodic safety analyses are not meant for qualification of the plant components. Separate analyses are devoted to: start-up, qualification of components and materials, and aging. All these analyses are described in this presentation. The last chapter describes the experience obtained for PWR-900 and PWR-1300 units from 1986-1989.

Research and application of embedded real-time operating system

Science.gov (United States)

Zhang, Bo

2013-03-01

In this paper, based on the analysis of existing embedded real-time operating system, the architecture of an operating system is designed and implemented. The experimental results show that the design fully complies with the requirements of embedded real-time operating system, can achieve the purposes of reducing the complexity of embedded software design and improving the maintainability, reliability, flexibility. Therefore, this design program has high practical value.

Time-periodic solution of a 2D fourth-order nonlinear parabolic ...

Indian Academy of Sciences (India)

appropriate function space for the initial boundary value problem. ... time discretizations which allow much larger time steps than those of a standard implicit– explicit approach. ... set of ω-periodic X-valued measurable functions on R such that.

40 CFR 62.15150 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Science.gov (United States)

2010-07-01

... requirements during periods of startup, shutdown, and malfunction? 62.15150 Section 62.15150 Protection of... § 62.15150 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

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

Periodically operated bioreactors for the treatment of soils and leachates

International Nuclear Information System (INIS)

Irvine, R.L.; Cassidy, D.P.

1995-01-01

Limited contaminant bioavailability at concentrations above the required cleanup level reduces biodegradation rate and renders solid-phase bioremediation more cost effective than complete treatment in a bioslurry reactor. Slurrying followed by solid-phase bioremediation combines the advantages and minimizes the weaknesses of each treatment method when used alone. Periodic aeration during solid-phase bioremediation has the potential to lower treatment costs relative to continuous aeration. A biological treatment system consisting of slurrying followed by periodic aeration in solid-phase sequencing batch reactors (SP-SBRs) was developed and tested in the laboratory using a silty loam contaminated predominantly with the plasticizer bis(2-ethylhexyl)phthalate (BEHP) or (DEHP) and a silty clay loam contaminated with diesel fuel. The first experiment evaluated the effect of water content and mixing time during slurrying on subsequent treatment in continuously aerated solid-phase bioreactors. The second experiment compared treatment of slurried soil in SP-SBRs using three different periodic aeration strategies with continuous aeration

Embedded and real-time operating systems

CERN Document Server

Wang, K C

2017-01-01

This book covers the basic concepts and principles of operating systems, showing how to apply them to the design and implementation of complete operating systems for embedded and real-time systems. It includes all the foundational and background information on ARM architecture, ARM instructions and programming, toolchain for developing programs, virtual machines for software implementation and testing, program execution image, function call conventions, run-time stack usage and link C programs with assembly code. It describes the design and implementation of a complete OS for embedded systems in incremental steps, explaining the design principles and implementation techniques. For Symmetric Multiprocessing (SMP) embedded systems, the author examines the ARM MPcore processors, which include the SCU and GIC for interrupts routing and interprocessor communication and synchronization by Software Generated Interrupts (SGIs). Throughout the book, complete working sample systems demonstrate the design principles and...

Revision of failed hip resurfacing to total hip arthroplasty rapidly relieves pain and improves function in the early post operative period

Directory of Open Access Journals (Sweden)

Muirhead-Allwood Sarah K

2010-11-01

Full Text Available Abstract We reviewed the results of 25 consecutive patients who underwent revision of a hip resurfacing prosthesis to a total hip replacement. Revisions were performed for recurrent pain and effusion, infection and proximal femoral fractures. Both components were revised in 20 cases. There were 12 male and 13 female patients with average time to revision of 34.4 and 26.4 months respectively. The mean follow up period was 12.7 months (3 to 31. All patients reported relief of pain and excellent satisfaction scores. Two patients experienced stiffness up to three months post operatively. Pre operative Oxford, Harris and WOMAC hip scores were 39.1, 36.4 and 52.2 respectively. Mean post operative scores at last follow up were 17.4, 89.8 and 6.1 respectively (p

46 CFR 167.60-5 - Period of time for which valid.

Science.gov (United States)

2010-10-01

... SCHOOL SHIPS Certificates of Inspection § 167.60-5 Period of time for which valid. A certificate of inspection for any period less than one year shall not be issued, but nothing herein shall be construed as preventing the revocation or suspension of a certificate of inspection in case such process is authorized by...

40 CFR 60.1695 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Science.gov (United States)

2010-07-01

... requirements during periods of startup, shutdown, and malfunction? 60.1695 Section 60.1695 Protection of... Requirements § 60.1695 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

Advanced Hard Real-Time Operating System, the Maruti Project. Part 2.

Science.gov (United States)

1997-01-01

Real - Time Operating System , The Maruti Project DASG-60-92-C-0055 5b. Program Element # 62301E 6. Author(s...The maruti hard real - time " operating system . A CM SIGOPS, Operating Systems Review. 23:90-106, July 1989. 254 !1 110) C. L. Liu and J. Layland...February 14, 1995 Abstract The Maruti Real - Time Operating System was developed for applications that must meet hard real-time constraints. In order

Almost Periodic Solution for Memristive Neural Networks with Time-Varying Delays

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Huaiqin Wu

2013-01-01

Full Text Available This paper is concerned with the dynamical stability analysis for almost periodic solution of memristive neural networks with time-varying delays. Under the framework of Filippov solutions, by applying the inequality analysis techniques, the existence and asymptotically almost periodic behavior of solutions are discussed. Based on the differential inclusions theory and Lyapunov functional approach, the stability issues of almost periodic solution are investigated, and a sufficient condition for the existence, uniqueness, and global exponential stability of the almost periodic solution is established. Moreover, as a special case, the condition which ensures the global exponential stability of a unique periodic solution is also presented for the considered memristive neural networks. Two examples are given to illustrate the validity of the theoretical results.

Natural world physical, brain operational, and mind phenomenal space-time

Science.gov (United States)

Fingelkurts, Andrew A.; Fingelkurts, Alexander A.; Neves, Carlos F. H.

2010-06-01

Concepts of space and time are widely developed in physics. However, there is a considerable lack of biologically plausible theoretical frameworks that can demonstrate how space and time dimensions are implemented in the activity of the most complex life-system - the brain with a mind. Brain activity is organized both temporally and spatially, thus representing space-time in the brain. Critical analysis of recent research on the space-time organization of the brain's activity pointed to the existence of so-called operational space-time in the brain. This space-time is limited to the execution of brain operations of differing complexity. During each such brain operation a particular short-term spatio-temporal pattern of integrated activity of different brain areas emerges within related operational space-time. At the same time, to have a fully functional human brain one needs to have a subjective mental experience. Current research on the subjective mental experience offers detailed analysis of space-time organization of the mind. According to this research, subjective mental experience (subjective virtual world) has definitive spatial and temporal properties similar to many physical phenomena. Based on systematic review of the propositions and tenets of brain and mind space-time descriptions, our aim in this review essay is to explore the relations between the two. To be precise, we would like to discuss the hypothesis that via the brain operational space-time the mind subjective space-time is connected to otherwise distant physical space-time reality.

Real time operation of a multiple gamma measurement installation

International Nuclear Information System (INIS)

Philippot, J.C.; Lefevre, J.

1980-01-01

This paper describes a multiple measurement channel facility for fine gamma spectrometry, its real time operation, and the new possibilities which it offers. The installation is presented in its twofold electronic and processing aspects, by considering its architecture, its hard and software, and its data processing package. Real time operation requires customized general organization, perfect instantaneous knowledge of the status of all the units, and a sound hierarchy between the various participants, operators as well as requestors. The care inherent in the installation itself and in the definition of its operation explains its new possibilities. (Auth.)

Intra-operative remifentanil might influence pain levels in the immediate postoperative period after major abdominal surgery

DEFF Research Database (Denmark)

Hansen, EG; Duedahl, Tina H; Rømsing, Janne

2005-01-01

Remifentanil, a widely used analgesic agent in anaesthesia, has a rapid onset and short duration of action. In clinical settings, this requires an appropriate pain strategy to prevent unacceptable pain in the post-operative period. The aim of this study was to investigate whether remifentanil had...... any impact on post-operative pain and opioid consumption after major abdominal surgery....

Modal Vibration Control in Periodic Time-Varying Structures with Focus on Rotor Blade Systems

DEFF Research Database (Denmark)

Christensen, Rene Hardam; Santos, Ilmar

2004-01-01

of active modal controllers. The main aim is to reduce vibrations in periodic time-varying structures. Special emphasis is given to vibration control of coupled bladed rotor systems. A state feedback modal control law is developed based on modal analysis in periodic time-varying structures. The first step...... in the procedure is a transformation of the model into a time-invariant modal form by applying the modal matrices, which are also periodic time-variant. Due to coupled rotor and blade motions complex vibration modes occur in the modal transformed state space model. This implies that the modal transformed model...

12 CFR 516.10 - How does OTS compute time periods under this part?

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 5 2010-01-01 2010-01-01 false How does OTS compute time periods under this part? 516.10 Section 516.10 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF THE TREASURY APPLICATION PROCESSING PROCEDURES § 516.10 How does OTS compute time periods under this part? In computing...

ESTIMATION OF MULTI-MODAL ANALGESIA ADEQUACY IN THE PERIOPERATIVE PERIOD AT LONG-TERMED TRAUMATIZING ABDOMINAL OPERATIVE INTERVENTIONS

Directory of Open Access Journals (Sweden)

V. Kh. Sharipova

2015-01-01

Full Text Available PURPOSE OF THE STUDY. Improvement of perioperative multimodal analgesia at long­termed traumatizing abdominal interventions with estimation of its effectiveness.MATERIALS AND METHODS. Eighty six patients have been examined and divided into 3 groups depending on anesthesia and postoperative pain relief methods.RESULTS. The effectiveness of perioperative multi­modal analgesia using methods affecting the whole pathogenesis of pain has been revealed. Minimal stress of central and peripheral hemodynamics parameters, less evident pain syndrome in the post­operative period, economic effect shown up by the decrease of the use of narcotic analgesics both in intra­ and post­operative period have been observed.CONCLUSION. Algorithm of perioperative multi­modal analgesia at long­termed and traumatizing abdominal operative interventions has been developed. 

Mixed-mode Operating System for Real-time Performance

Directory of Open Access Journals (Sweden)

M.M. Hasan

2017-11-01

Full Text Available The purpose of the mixed-mode system research is to handle devices with the accuracy of real-time systems and at the same time, having all the benefits and facilities of a matured Graphic User Interface (GUI operating system which is typically nonreal-time. This mixed-mode operating system comprising of a real-time portion and a non-real-time portion was studied and implemented to identify the feasibilities and performances in practical applications (in the context of scheduled the real-time events. In this research an i8751 microcontroller-based hardware was used to measure the performance of the system in real-time-only as well as non-real-time-only configurations. The real-time portion is an 486DX-40 IBM PC system running under DOS-based realtime kernel and the non-real-time portion is a Pentium III based system running under Windows NT. It was found that mixed-mode systems performed as good as a typical realtime system and in fact, gave many additional benefits such as simplified/modular programming and load tolerance.

Plasticity of the intrinsic period of the human circadian timing system.

Directory of Open Access Journals (Sweden)

Frank A J L Scheer

2007-08-01

Full Text Available Human expeditions to Mars will require adaptation to the 24.65-h Martian solar day-night cycle (sol, which is outside the range of entrainment of the human circadian pacemaker under lighting intensities to which astronauts are typically exposed. Failure to entrain the circadian time-keeping system to the desired rest-activity cycle disturbs sleep and impairs cognitive function. Furthermore, differences between the intrinsic circadian period and Earth's 24-h light-dark cycle underlie human circadian rhythm sleep disorders, such as advanced sleep phase disorder and non-24-hour sleep-wake disorders. Therefore, first, we tested whether exposure to a model-based lighting regimen would entrain the human circadian pacemaker at a normal phase angle to the 24.65-h Martian sol and to the 23.5-h day length often required of astronauts during short duration space exploration. Second, we tested here whether such prior entrainment to non-24-h light-dark cycles would lead to subsequent modification of the intrinsic period of the human circadian timing system. Here we show that exposure to moderately bright light ( approximately 450 lux; approximately 1.2 W/m(2 for the second or first half of the scheduled wake episode is effective for entraining individuals to the 24.65-h Martian sol and a 23.5-h day length, respectively. Estimations of the circadian periods of plasma melatonin, plasma cortisol, and core body temperature rhythms collected under forced desynchrony protocols revealed that the intrinsic circadian period of the human circadian pacemaker was significantly longer following entrainment to the Martian sol as compared to following entrainment to the 23.5-h day. The latter finding of after-effects of entrainment reveals for the first time plasticity of the period of the human circadian timing system. Both findings have important implications for the treatment of circadian rhythm sleep disorders and human space exploration.

REAL TIME SYSTEM OPERATIONS 2006-2007

Energy Technology Data Exchange (ETDEWEB)

Eto, Joseph H.; Parashar, Manu; Lewis, Nancy Jo

2008-08-15

The Real Time System Operations (RTSO) 2006-2007 project focused on two parallel technical tasks: (1) Real-Time Applications of Phasors for Monitoring, Alarming and Control; and (2) Real-Time Voltage Security Assessment (RTVSA) Prototype Tool. The overall goal of the phasor applications project was to accelerate adoption and foster greater use of new, more accurate, time-synchronized phasor measurements by conducting research and prototyping applications on California ISO's phasor platform - Real-Time Dynamics Monitoring System (RTDMS) -- that provide previously unavailable information on the dynamic stability of the grid. Feasibility assessment studies were conducted on potential application of this technology for small-signal stability monitoring, validating/improving existing stability nomograms, conducting frequency response analysis, and obtaining real-time sensitivity information on key metrics to assess grid stress. Based on study findings, prototype applications for real-time visualization and alarming, small-signal stability monitoring, measurement based sensitivity analysis and frequency response assessment were developed, factory- and field-tested at the California ISO and at BPA. The goal of the RTVSA project was to provide California ISO with a prototype voltage security assessment tool that runs in real time within California ISO?s new reliability and congestion management system. CERTS conducted a technical assessment of appropriate algorithms, developed a prototype incorporating state-of-art algorithms (such as the continuation power flow, direct method, boundary orbiting method, and hyperplanes) into a framework most suitable for an operations environment. Based on study findings, a functional specification was prepared, which the California ISO has since used to procure a production-quality tool that is now a part of a suite of advanced computational tools that is used by California ISO for reliability and congestion management.

Application of total care time and payment per unit time model for physician reimbursement for common general surgery operations.

Science.gov (United States)

Chatterjee, Abhishek; Holubar, Stefan D; Figy, Sean; Chen, Lilian; Montagne, Shirley A; Rosen, Joseph M; Desimone, Joseph P

2012-06-01

The relative value unit system relies on subjective measures of physician input in the care of patients. A payment per unit time model incorporates surgeon reimbursement to the total care time spent in the operating room, postoperative in-house, and clinic time to define payment per unit time. We aimed to compare common general surgery operations by using the total care time and payment per unit time method in order to demonstrate a more objective measurement for physician reimbursement. Average total physician payment per case was obtained for 5 outpatient operations and 4 inpatient operations in general surgery. Total care time was defined as the sum of operative time, 30 minutes per hospital day, and 30 minutes per office visit for each operation. Payment per unit time was calculated by dividing the physician reimbursement per case by the total care time. Total care time, physician payment per case, and payment per unit time for each type of operation demonstrated that an average payment per time spent for inpatient operations was $455.73 and slightly more at $467.51 for outpatient operations. Partial colectomy with primary anastomosis had the longest total care time (8.98 hours) and the least payment per unit time ($188.52). Laparoscopic gastric bypass had the highest payment per time ($707.30). The total care time and payment per unit time method can be used as an adjunct to compare reimbursement among different operations on an institutional level as well as on a national level. Although many operations have similar payment trends based on time spent by the surgeon, payment differences using this methodology are seen and may be in need of further review. Copyright © 2012 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Relationship between laparoscopic cholecystectomy operative time and carbonyl hemoglobin content

Directory of Open Access Journals (Sweden)

ZHANG Qi

2013-06-01

Full Text Available ObjectiveTo investigate whether operative time of laparoscopic cholecystectomy impacts the carbonyl hemoglobin (COHb concentration in peripheral blood. MethodsForty patients with gallstones and indications for laparoscopic cholecystectomy were enrolled in the study. Peripheral venous blood samples were collected at the beginning and end of the operative procedure. COHb concentration was measured by UV spectroscopy. The significance of changes in COHb concentration in relation to time of the operative procedure (rounded to the nearest minute was assessed by statistical correlation coefficient test. ResultsThe laparoscopic procedure was completed in 38 cases, and two patients required conversion to laparotomy. The content of COHb in peripheral venous blood had significantly increased during the laparoscopic operation (operation beginning: 11.07%±1.18% vs. operation end: 1.44%±0.26%, P＜0.05. The change was positively correlated with operation time (r=0.85. ConclusionCarbon monoxide produced during the laparoscopic cholecystectomy procedure can lead to an increase in peripheral venous blood COHb. The longer the operation lasts, the greater the increase in COHb.

Stability and periodicity of solutions for delay dynamic systems on time scales

Directory of Open Access Journals (Sweden)

Zhi-Qiang Zhu

2014-04-01

Full Text Available This article concerns the stability and periodicity of solutions to the delay dynamic system $$ x^{\\triangle}(t=A(t x(t + F(t, x(t, x(g(t+C(t $$ on a time scale. By the inequality technique for vectors, we obtain some stability criteria for the above system. Then, by using the Horn fixed point theorem, we present some conditions under which our system is asymptotically periodic and its periodic solution is unique. In particular, the periodic solution is positive under proper assumptions.

Effect of Streamflow Forecast Uncertainty on Real-Time Reservoir Operation

Science.gov (United States)

Zhao, T.; Cai, X.; Yang, D.

2010-12-01

Various hydrological forecast products have been applied to real-time reservoir operation, including deterministic streamflow forecast (DSF), DSF-based probabilistic streamflow forecast (DPSF), and ensemble streamflow forecast (ESF), which represent forecast uncertainty in the form of deterministic forecast error, deterministic forecast error-based uncertainty distribution, and ensemble forecast errors, respectively. Compared to previous studies that treat these forecast products as ad hoc inputs for reservoir operation models, this paper attempts to model the uncertainties involved in the various forecast products and explores their effect on real-time reservoir operation decisions. In hydrology, there are various indices reflecting the magnitude of streamflow forecast uncertainty; meanwhile, few models illustrate the forecast uncertainty evolution process. This research introduces Martingale Model of Forecast Evolution (MMFE) from supply chain management and justifies its assumptions for quantifying the evolution of uncertainty in streamflow forecast as time progresses. Based on MMFE, this research simulates the evolution of forecast uncertainty in DSF, DPSF, and ESF, and applies the reservoir operation models (dynamic programming, DP; stochastic dynamic programming, SDP; and standard operation policy, SOP) to assess the effect of different forms of forecast uncertainty on real-time reservoir operation. Through a hypothetical single-objective real-time reservoir operation model, the results illustrate that forecast uncertainty exerts significant effects. Reservoir operation efficiency, as measured by a utility function, decreases as the forecast uncertainty increases. Meanwhile, these effects also depend on the type of forecast product being used. In general, the utility of reservoir operation with ESF is nearly as high as the utility obtained with a perfect forecast; the utilities of DSF and DPSF are similar to each other but not as efficient as ESF. Moreover

Choice reaction time in patients with post-operative cognitive dysfunction

DEFF Research Database (Denmark)

Steinmetz, J.; Rasmussen, L.S.

2008-01-01

BACKGROUND: Post-operative cognitive dysfunction (POCD) is detected by administration of a neuropsychological test battery. Reaction time testing is at present not included as a standard test. Choice reaction time (CRT) data from the first International Study of Post-operative Cognitive Dysfunction...... in nine countries. CRT was measured 52 times using the four boxes test. Patients performed the test before surgery (n=1083), at 1 week (n=926) and at 3 months (n=852) post-operatively. CRT for the individual patient was determined as the median time of correct responses. The usefulness of the CRT...... had a significantly longer CRT. ROC curves revealed that a reaction time of 813 ms was the most appropriate cut-off at 1 week and 762 ms at 3 months but the positive predictive value for POCD was low: 34.4% and 14.7%, respectively. CONCLUSIONS: Post-operative cognitive dysfunction is associated...

The spectrum of the periodic point perturbation of the three-dimensional Landau operator

International Nuclear Information System (INIS)

Gejler, V.A.; Demidov, V.V.

1995-01-01

The three-dimensional Schroedinger operator with magnetic field perturbated by the periodic sum of zero-range potentials is investigated. The explicit form of the decomposition of the resolnebt of the operator over the spectrum of the irreducible representations of the group of magnetic translations was found in the case of a rational flux. The explicit form of the dispersion laws was found, the description of the spectrum was given and the qualitative investigation of the spectrum was foun, the description of the spectrum was given and the qualitative of the spectrum was carried out in the case of an integer flux (in particular, it was found that there are no more than one gap). 30 refs

ART THERAPY MANAGEMENT IN THE PRE-OPERATIVE PERIOD IN PEDIATRICS

Directory of Open Access Journals (Sweden)

Ana Cláudia Afonso Valladares

2004-04-01

Full Text Available Every child, particularly those who will be submitted to surgery, needs to express themselves, createand establish relationships with the world. This study was based on qualitative studies which were, in turn,substantiated on the behavioral changes of patients and their images. It was developed in the pediatric clinic of apublic hospital in the city of Goiânia/GO in a two years’ period (1998-2000. The target population consisted ofhospitalized children in the pre-operative process. It was concluded that great therapeutic benefit was achievedfrom the use of art therapy for this population as it helped the children to recover their mental balance, thusstrengthening a healthier side of the child which had been deadened by the illness, hospitalization and treatment.

The Dynamic Multi-Period Vehicle Routing Problem

DEFF Research Database (Denmark)

Wen, Min; Cordeau, Jean-Francois; Laporte, Gilbert

This paper considers the Dynamic Multi-Period Vehicle Routing Problem which deals with the distribution of orders from a depot to a set of customers over a multi-period time horizon. Customer orders and their feasible service periods are dynamically revealed over time. The objectives are to minim......This paper considers the Dynamic Multi-Period Vehicle Routing Problem which deals with the distribution of orders from a depot to a set of customers over a multi-period time horizon. Customer orders and their feasible service periods are dynamically revealed over time. The objectives...... are to minimize total travel costs and customer waiting, and to balance the daily workload over the planning horizon. This problem originates from a large distributor operating in Sweden. It is modeled as a mixed integer linear program, and solved by means of a three-phase heuristic that works over a rolling...... planning horizon. The multi-objective aspect of the problem is handled through a scalar technique approach. Computational results show that our solutions improve upon those of the Swedish distributor....

Time trends, improvements and national auditing of rectal cancer management over an 18-year period.

Science.gov (United States)

Kodeda, K; Johansson, R; Zar, N; Birgisson, H; Dahlberg, M; Skullman, S; Lindmark, G; Glimelius, B; Påhlman, L; Martling, A

2015-09-01

The main aims were to explore time trends in the management and outcome of patients with rectal cancer in a national cohort and to evaluate the possible impact of national auditing on overall outcomes. A secondary aim was to provide population-based data for appraisal of external validity in selected patient series. Data from the Swedish ColoRectal Cancer Registry with virtually complete national coverage were utilized in this cohort study on 29 925 patients with rectal cancer diagnosed between 1995 and 2012. Of eligible patients, nine were excluded. During the study period, overall, relative and disease-free survival increased. Postoperative mortality after 30 and 90 days decreased to 1.7% and 2.9%. The 5-year local recurrence rate dropped to 5.0%. Resection margins improved, as did peri-operative blood loss despite more multivisceral resections being performed. Fewer patients underwent palliative resection and the proportion of non-operated patients increased. The proportions of temporary and permanent stoma formation increased. Preoperative radiotherapy and chemoradiotherapy became more common as did multidisciplinary team conferences. Variability in rectal cancer management between healthcare regions diminished over time when new aspects of patient care were audited. There have been substantial changes over time in the management of patients with rectal cancer, reflected in improved outcome. Much indirect evidence indicates that auditing matters, but without a control group it is not possible to draw firm conclusions regarding the possible impact of a quality control registry on faster shifts in time trends, decreased variability and improvements. Registry data were made available for reference. Colorectal Disease © 2015 The Association of Coloproctology of Great Britain and Ireland.

Periodicity and stability for variable-time impulsive neural networks.

Science.gov (United States)

Li, Hongfei; Li, Chuandong; Huang, Tingwen

2017-10-01

The paper considers a general neural networks model with variable-time impulses. It is shown that each solution of the system intersects with every discontinuous surface exactly once via several new well-proposed assumptions. Moreover, based on the comparison principle, this paper shows that neural networks with variable-time impulse can be reduced to the corresponding neural network with fixed-time impulses under well-selected conditions. Meanwhile, the fixed-time impulsive systems can be regarded as the comparison system of the variable-time impulsive neural networks. Furthermore, a series of sufficient criteria are derived to ensure the existence and global exponential stability of periodic solution of variable-time impulsive neural networks, and to illustrate the same stability properties between variable-time impulsive neural networks and the fixed-time ones. The new criteria are established by applying Schaefer's fixed point theorem combined with the use of inequality technique. Finally, a numerical example is presented to show the effectiveness of the proposed results. Copyright © 2017 Elsevier Ltd. All rights reserved.

Estimation of efficiency of new local rehabilitation method at the early post-operative period after dental implantation

Directory of Open Access Journals (Sweden)

A. V. Pasechnik

2017-01-01

  Summary Despite of success of dental implantation, there are often complications at the early post-operative period of implant placing associated with wound damage and aseptic inflammation. Purpose of the work is studying clinical efficiency of combined local application of new mucosal gel “Apior” and magnetotherapy at the early post-operative period after dental implantation. Combined local application of the mucosal gel “Apior” and pulsating low-frequency electromagnetic field in the complex medical treatment of patients after conducting an operation of setting dental implants favourably affects the common state of patients and clinical symptoms of inflammation in the area of operating wound. As compared with patients who had traditional anti-inflammatory therapy, the patients treated with local application of apigel and magnetoterapy had decline of edema incidence, of gingival mucosa hyperemia, of discomfort in the area of conducted operation. There occurred more rapid improvement of inflammation painfulness, which correlated with the improvement of hygienic state of oral cavity and promoted to prevention of bacterial content of damaged mucous surfaces. Estimation of microvasculatory blood stream by the method of ultrasonic doppler flowmetry revealed more rapid normalization of volume and linear high systole speed of blood stream in the periimplant tissues in case of use of new complex local rehabilitation method, that testified to the less pronounced inflammation of oral mucosa after the operation. The authors came to conclusion that the local application of the offered method of medical treatment of early post-operative complications of dental implantation reduces terms of renewal of structural-functional integrity of oral mucosa, helps in preventing development of inflammatory complications and strengthening endosseus implant. The inclusion in the treatment management of a new combined method of application of mucosal gel “Apior” and

Timing system for multi-bunch/multi-train operation at ATF

International Nuclear Information System (INIS)

Naito, T.; Hayano, H.; Urakawa, J.; Imai, T.

2000-01-01

A timing system has been constructed for multi-bunch/multi-train operation at KEK-ATF. The linac accelerates 20 bunches of multi-bunch with 2.8 ns spacing. The Damping Ring stores up to 5 trains of multi-bunch. The timing system is required to provide flexible operation mode and bucket selection. A personal computer is used for manipulating the timing. The performance of kicker magnets at the injection/extruction is key issue for multi-train operation. The hardware and the test results are presented. (author)

Pre-operative MRI of anorectal anomalies in the newborn period

International Nuclear Information System (INIS)

McHugh, K.; Dudley, N.E.; Tam, P.

1995-01-01

Nine infants (six boys, three girls) with anorectal anomalies were examined in the immediate newborn period, prior to corrective surgery, with MRI. Three high, one intermediate and five low anomalies were found at MRI - one patient with a 'low' lesion was subsequently found at surgery 2 months later to have a high anorectal anomaly. This infant had passed meconium per urethram soon after the MRI study, prompting the need for a protective colostomy and stressing the importance of a thorough clinical examination of babies with anorectal malformations. The MRI results and findings at surgery were in agreement in all other patients (n=8). Hydronephrosis was evident in two and renal agenesis in one patient. Sacrococcygeal hypoplasia was found in two and two hemivertebrae in one infant. No spinal cord lesion was identified. One fistula was evident on MRI but four were later found at surgery. Uniformly hyperintense T1 signal meconium was seen in all nine newborns, allowing for easy differentiation of rectal contents from rectal wall and the adjacent musculature. MRI can provide useful information regarding the development of the puborectal and external anal sphincter muscles, can help guide the pull-through procedure and help predict future continence pre-operatively in the newborn period. (orig.)

Pre-operative MRI of anorectal anomalies in the newborn period

Energy Technology Data Exchange (ETDEWEB)

McHugh, K. [Dept. of Radiology, John Radcliffe Hospital, Oxford (United Kingdom); Dudley, N.E. [Dept. of Paediatric Surgery, John Radcliffe Hospital, Oxford (United Kingdom); Tam, P. [Dept. of Paediatric Surgery, John Radcliffe Hospital, Oxford (United Kingdom)

1995-11-01

Nine infants (six boys, three girls) with anorectal anomalies were examined in the immediate newborn period, prior to corrective surgery, with MRI. Three high, one intermediate and five low anomalies were found at MRI - one patient with a `low` lesion was subsequently found at surgery 2 months later to have a high anorectal anomaly. This infant had passed meconium per urethram soon after the MRI study, prompting the need for a protective colostomy and stressing the importance of a thorough clinical examination of babies with anorectal malformations. The MRI results and findings at surgery were in agreement in all other patients (n=8). Hydronephrosis was evident in two and renal agenesis in one patient. Sacrococcygeal hypoplasia was found in two and two hemivertebrae in one infant. No spinal cord lesion was identified. One fistula was evident on MRI but four were later found at surgery. Uniformly hyperintense T1 signal meconium was seen in all nine newborns, allowing for easy differentiation of rectal contents from rectal wall and the adjacent musculature. MRI can provide useful information regarding the development of the puborectal and external anal sphincter muscles, can help guide the pull-through procedure and help predict future continence pre-operatively in the newborn period. (orig.)

Prediction of the time-dependent failure rate for normally operating components taking into account the operational history

International Nuclear Information System (INIS)

Vrbanic, I.; Simic, Z.; Sljivac, D.

2008-01-01

The prediction of the time-dependent failure rate has been studied, taking into account the operational history of a component used in applications such as system modeling in a probabilistic safety analysis in order to evaluate the impact of equipment aging and maintenance strategies on the risk measures considered. We have selected a time-dependent model for the failure rate which is based on the Weibull distribution and the principles of proportional age reduction by equipment overhauls. Estimation of the parameters that determine the failure rate is considered, including the definition of the operational history model and likelihood function for the Bayesian analysis of parameters for normally operating repairable components. The operational history is provided as a time axis with defined times of overhauls and failures. An example for demonstration is described with prediction of the future behavior for seven different operational histories. (orig.)

Green's function asymptotics near the internal edges of spectra of periodic elliptic operators. Spectral edge case

KAUST Repository

Kuchment, Peter

2012-06-21

Precise asymptotics known for the Green\\'s function of the Laplace operator have found their analogs for periodic elliptic operators of the second order at and below the bottom of the spectrum. Due to the band-gap structure of the spectra of such operators, the question arises whether similar results can be obtained near or at the edges of spectral gaps. As the result of this work shows, this is possible at a spectral edge when the dimension d ≥ 3. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Green's function asymptotics near the internal edges of spectra of periodic elliptic operators. Spectral edge case

KAUST Repository

Kuchment, Peter; Raich, Andrew

2012-01-01

Precise asymptotics known for the Green's function of the Laplace operator have found their analogs for periodic elliptic operators of the second order at and below the bottom of the spectrum. Due to the band-gap structure of the spectra of such operators, the question arises whether similar results can be obtained near or at the edges of spectral gaps. As the result of this work shows, this is possible at a spectral edge when the dimension d ≥ 3. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Periodic safety review of operational nuclear power plants. A publication within the NUSS programme

International Nuclear Information System (INIS)

1994-01-01

This Safety Guide which supplements the IAEA Safety Fundamentals: The Safety of Nuclear Installations and the Code on the Safety of Nuclear Power Plants: Operation, forms part of the Agency's programme, referred to as the NUSS programme, for establishing Codes and Guides relating to nuclear power plants. A list of NUSS publications is given at the end of this book. This Guide was drafted on the basis of a systematic review approach that was endorsed by the IAEA Conference on the Safety of Nuclear Power: Strategy for the Future. The purpose of this Safety Guide is to provide guidance on the conduct of Periodic Safety Reviews (PSRs) for an operational nuclear power plant. The Guide is directed at both owners/operators and regulators. This Safety Guide deals with the PSR of an operational nuclear power plant. A PSR is a comprehensive safety review addressing all important aspects of safety, carried out at regular intervals. 22 refs, 4 figs

Resolvent estimates in homogenisation of periodic problems of fractional elasticity

Science.gov (United States)

Cherednichenko, Kirill; Waurick, Marcus

2018-03-01

We provide operator-norm convergence estimates for solutions to a time-dependent equation of fractional elasticity in one spatial dimension, with rapidly oscillating coefficients that represent the material properties of a viscoelastic composite medium. Assuming periodicity in the coefficients, we prove operator-norm convergence estimates for an operator fibre decomposition obtained by applying to the original fractional elasticity problem the Fourier-Laplace transform in time and Gelfand transform in space. We obtain estimates on each fibre that are uniform in the quasimomentum of the decomposition and in the period of oscillations of the coefficients as well as quadratic with respect to the spectral variable. On the basis of these uniform estimates we derive operator-norm-type convergence estimates for the original fractional elasticity problem, for a class of sufficiently smooth densities of applied forces.

Parametric effect of a spatially periodic voltage depression on operation of Cerenkov sources of electromagnetic radiation

International Nuclear Information System (INIS)

Nusinovich, G.S.; Vlasov, A.N.

1994-01-01

In microwave sources of coherent Cerenkov radiation the electrons usually propagate near the rippled wall of a slow-wave structure. These ripples cause the periodic modulation of electron potential depression, and therefore, lead to periodic modulation of electron axial velocities. Since the period of this electrostatic pumping is the period of the slow-wave structure the parametric coupling of electrons to originally nonsynchronous spatial harmonics of the microwave field may occur. This effect can be especially important for backward-wave oscillators (BWO's) driven by high current, relativistic electron beams. In the paper both linear and nonlinear theories of the relativistic resonant BWO with periodic modulation of electron axial velocities are developed and results illustrating the evolution of the linear gain function and the efficiency of operation in the large-signal regime are presented

Calculations of Changes in Reactivity during some regular periods of operation of JEN-1 MOD Reactor

International Nuclear Information System (INIS)

Alcala Ruiz, F.

1973-01-01

By a Point-Reactor model and Perturbation Theory, changes in reactivity during some regular operating periods of JEN-1 MOD Reactor have been calculated and compared with available measured values. they were in good agreement. Also changes in reactivity have been calculated during operations at higher power levels than the present one, concluding some practical consequences for the case of increasing the present power of this reactor. (Author)

A Real-Time Simulation Platform for Power System Operation

DEFF Research Database (Denmark)

Cha, Seung-Tae; Østergaard, Jacob; Wu, Qiuwei

2010-01-01

This paper describes the real-time digital simulation platform that can be used for power system operation, analysis, and power system modeling. This particular platform gives grid operators, planners and researchers the opportunity to observe how a power system behaves and can be used...... in real time. Various phenomena commonly encountered when dealing with the two-area system is studied. Despite its small size, it mimics very closely the behavior of typical systems in actual operation. The electromagnetic transient type of simulation made in RSCAD enables the study of fast and detailed...... phenomena like single-phase faults in the two-area network and to observe their effects on a larger time scale. Also, the case study of 11 bus system with 5 generators has been also used and the results are presented....

How Repeated Time To Event (RTTE) modelling of opioid requests after surgery may improve future post-operative pain management

DEFF Research Database (Denmark)

Juul, Rasmus Vestergaard; Rasmussen, Sten; Kreilgaard, Mads

at Orthopaedic Department, Aalborg University Hospital, Denmark during the period May-Dec 2012. Morphine administration times (estimated precision: ±5mins), formulations and doses were extracted from medical journals in the hospitalization period or until 96 hours after surgery. RTTE modelling was performed......Title: How Repeated Time To Event (RTTE) modelling of opioid requests after surgery may improve future post-operative pain management Author: Rasmus Vestergaard Juul (1) Sten Rasmussen (2) Mads Kreilgaard (1) Ulrika S. H. Simonsson (3) Lona Louring Christrup (1) Trine Meldgaard Lund (1) Institution...... of surgery specific, drug concentration related, population specific and/or time-varying covariates of opioid requests and pain events. Conclusions: A framework has been developed based on RTTE modelling that may help improve future pain management by 1) Identification of surgery specific patterns in pain...

Reducing Operating Room Costs Through Real-Time Cost Information Feedback: A Pilot Study.

Science.gov (United States)

Tabib, Christian H; Bahler, Clinton D; Hardacker, Thomas J; Ball, Kevin M; Sundaram, Chandru P

2015-08-01

To create a protocol for providing real-time operating room (OR) cost feedback to surgeons. We hypothesize that this protocol will reduce costs in a responsible way without sacrificing quality of care. All OR costs were obtained and recorded for robot-assisted partial nephrectomy and laparoscopic donor nephrectomy. Before the beginning of this project, costs pertaining to the 20 most recent cases were analyzed. Items were identified from previous cases as modifiable for replacement or omission. Timely feedback of total OR costs and cost of each item used was provided to the surgeon after each case, and costs were analyzed. A cost analysis of the robot-assisted partial nephrectomy before the washout period indicates expenditures of $5243.04 per case. Ten recommended modifiable items were found to have an average per case cost of $1229.33 representing 23.4% of the total cost. A postwashout period cost analysis found the total OR cost decreased by $899.67 (17.2%) because of changes directly related to the modifiable items. Therefore, 73.2% of the possible identified savings was realized. The same stepwise approach was applied to laparoscopic donor nephrectomies. The average total cost per case before the washout period was $3530.05 with $457.54 attributed to modifiable items. After the washout period, modifiable items costs were reduced by $289.73 (8.0%). No complications occurred in the donor nephrectomy cases while one postoperative complication occurred in the partial nephrectomy group. Providing surgeons with feedback related to OR costs may lead to a change in surgeon behavior and decreased overall costs. Further studies are needed to show equivalence in patient outcomes.

The Periodic Measurement of the Airborne Radioactivity In Controlled Area of KOMAC

Energy Technology Data Exchange (ETDEWEB)

Park, Jeong-Min; Park, Sung-Kyun; Min, Yi-Sub; Cho, Yong-Sub [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

Korea Multipurpose Accelerator Complex (KOMAC) to start the performance operation in the second half of 2013, is currently operated in each beamline 20-MeV and 100-MeV. The accelerator operation period is simply divided by three operation cycles which are the maintenance checks period for accelerator device, the performance test period before driving accelerator and the operation period. During this operation period, beam is irradiated to target. At this time, the proton beams collide with the target material and a high dose of radiations such as gamma ray and neutron occurred. Radiation controlled area at the accelerator facility is divided into accelerator tunnel and beam utilization zone. As a result of measuring the airborne radioactivity in the controlled area in accordance with the operating cycle of the proton accelerator KOMAC, It was confirmed that the value of the airborne radioactivity does not significantly differ according to each accelerator operating cycles. And alpha and beta values measured inside the area that workers primarily work is very low indoor radon level than the value of the recommendations in multiple facilities.

Treatment of first metatarsophalangeal joint arthritis using hemiarthroplasty with a synthetic cartilage implant or arthrodesis: A comparison of operative and recovery time.

Science.gov (United States)

Glazebrook, Mark; Younger, Alastair S E; Daniels, Timothy R; Singh, Dishan; Blundell, Chris; de Vries, Gwyneth; Le, Ian L D; Nielsen, Dominic; Pedersen, M Elizabeth; Sakellariou, Anthony; Solan, Matthew; Wansbrough, Guy; Baumhauer, Judith F

2017-05-29

First metatarsophalangeal joint (MTPJ1) hemiarthroplasty using a novel synthetic cartilage implant was as effective and safe as MTPJ1 arthrodesis in a randomized clinical trial. We retrospectively evaluated operative time and recovery period for implant hemiarthroplasty (n=152) and MTPJ1 arthrodesis (n=50). Perioperative data were assessed for operative and anaesthesia times. Recovery and return to function were prospectively assessed with the Foot and Ankle Ability Measure (FAAM) Sports and Activities of Daily Living (ADL) subscales and SF-36 Physical Functioning (PF) subscore. Mean operative time for hemiarthroplasty was 35±12.3min and 58±21.5min for arthrodesis (pSport, FAAM ADL, and SF-36 PF subscores versus arthrodesis patients. MTPJ1 hemiarthroplasty with a synthetic cartilage implant took less operative time and resulted in faster recovery than arthrodesis. III, Retrospective case control study. Copyright © 2017 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

Time warp operating system version 2.7 internals manual

Science.gov (United States)

1992-01-01

The Time Warp Operating System (TWOS) is an implementation of the Time Warp synchronization method proposed by David Jefferson. In addition, it serves as an actual platform for running discrete event simulations. The code comprising TWOS can be divided into several different sections. TWOS typically relies on an existing operating system to furnish some very basic services. This existing operating system is referred to as the Base OS. The existing operating system varies depending on the hardware TWOS is running on. It is Unix on the Sun workstations, Chrysalis or Mach on the Butterfly, and Mercury on the Mark 3 Hypercube. The base OS could be an entirely new operating system, written to meet the special needs of TWOS, but, to this point, existing systems have been used instead. The base OS's used for TWOS on various platforms are not discussed in detail in this manual, as they are well covered in their own manuals. Appendix G discusses the interface between one such OS, Mach, and TWOS.

Problems of Software Detection of Periodic Features in a Time ...

African Journals Online (AJOL)

Problems arise when attempts are made to extract automatically, visually obvious periodic features indicative of defects in a vibration time series for diagnosis using computers. Such problems may be interpretational in nature arising either from insufficient knowledge of the mechanism, or the convolution of the source signal ...

Periodic solutions in reaction–diffusion equations with time delay

International Nuclear Information System (INIS)

Li, Li

2015-01-01

Spatial diffusion and time delay are two main factors in biological and chemical systems. However, the combined effects of them on diffusion systems are not well studied. As a result, we investigate a nonlinear diffusion system with delay and obtain the existence of the periodic solutions using coincidence degree theory. Moreover, two numerical examples confirm our theoretical results. The obtained results can also be applied in other related fields

Data verification and materials accountancy for two accounting periods

International Nuclear Information System (INIS)

Beedgen, R.

1985-01-01

In the framework of near-real-time accountancy for nuclear materials, safeguards statistical analysis based on the operator's data of a sequence of materials balance periods has been performed. Up to now, it is assumed that the operator's data are correct. A statistical model is presented that enables inspector verification measurements for a sequence of accounting periods to be included into a safeguards procedure. The analysis uses a two balance period and statistical concepts which are applied in the case of one accounting period. The interconnection of different safeguards measures shall be studied to get a basic idea about the procedure and it is shown that there might be fundamental differences to the one balance case

Unstable Periodic Orbit Analysis of Histograms of Chaotic Time Series

International Nuclear Information System (INIS)

Zoldi, S.M.

1998-01-01

Using the Lorenz equations, we have investigated whether unstable periodic orbits (UPOs) associated with a strange attractor may predict the occurrence of the robust sharp peaks in histograms of some experimental chaotic time series. Histograms with sharp peaks occur for the Lorenz parameter value r=60.0 but not for r=28.0 , and the sharp peaks for r=60.0 do not correspond to a histogram derived from any single UPO. However, we show that histograms derived from the time series of a non-Axiom-A chaotic system can be accurately predicted by an escape-time weighting of UPO histograms. copyright 1998 The American Physical Society

Embedded real-time operating system micro kernel design

Science.gov (United States)

Cheng, Xiao-hui; Li, Ming-qiang; Wang, Xin-zheng

2005-12-01

Embedded systems usually require a real-time character. Base on an 8051 microcontroller, an embedded real-time operating system micro kernel is proposed consisting of six parts, including a critical section process, task scheduling, interruption handle, semaphore and message mailbox communication, clock managent and memory managent. Distributed CPU and other resources are among tasks rationally according to the importance and urgency. The design proposed here provides the position, definition, function and principle of micro kernel. The kernel runs on the platform of an ATMEL AT89C51 microcontroller. Simulation results prove that the designed micro kernel is stable and reliable and has quick response while operating in an application system.

The Older of Two Trees: Young Children's Development of Operational Time

Science.gov (United States)

Kamii, Constance; Russell, Kelly A.

2010-01-01

Piaget (1971) made a distinction between intuitive (preoperational) time and operational (logico-mathematical) time. According to Piaget, operational time develops around 7-8 years of age and is characterized by children's ability to deduce, for example, that if A was born before B, A will always be older than B. When time is still intuitive,…

Advanced Hard Real-Time Operating System, The Maruti Project. Part 1.

Science.gov (United States)

1997-01-01

REAL - TIME OPERATING SYSTEM , THE MARUTI PROJECT Part 1 of 2 Ashok K. Agrawala Satish K. Tripathi Department of Computer Science University of Maryland...Hard Real - Time Operating System , The Maruti Project DASG-60-92-C-0055 5b. Program Element # 62301E 6. Author(s) 5c. Project # DRPB Ashok K. Agrawala...SdSA94), a real - time operating system developed at the I3nversity of Maryland, and conducted extensive experiments under various task

Online Synthesis for Operation Execution Time Variability on Digital Microfluidic Biochips

DEFF Research Database (Denmark)

Alistar, Mirela; Pop, Paul

2014-01-01

have assumed that each biochemical operation in an application is characterized by a worst-case execution time (wcet). However, during the execution of the application, due to variability and randomness in biochemical reactions, operations may finish earlier than their wcets. In this paper we propose...... an online synthesis strategy that re-synthesizes the application at runtime when operations experience variability in their execution time, obtaining thus shorter application execution times. The proposed strategy has been evaluated using several benchmarks....

The existence and global attractivity of almost periodic sequence solution of discrete-time neural networks

International Nuclear Information System (INIS)

Huang Zhenkun; Wang Xinghua; Gao Feng

2006-01-01

In this Letter, we discuss discrete-time analogue of a continuous-time cellular neural network. Sufficient conditions are obtained for the existence of a unique almost periodic sequence solution which is globally attractive. Our results demonstrate dynamics of the formulated discrete-time analogue as mathematical models for the continuous-time cellular neural network in almost periodic case. Finally, a computer simulation illustrates the suitability of our discrete-time analogue as numerical algorithms in simulating the continuous-time cellular neural network conveniently

Operating system for a real-time multiprocessor propulsion system simulator

Science.gov (United States)

Cole, G. L.

1984-01-01

The success of the Real Time Multiprocessor Operating System (RTMPOS) in the development and evaluation of experimental hardware and software systems for real time interactive simulation of air breathing propulsion systems was evaluated. The Real Time Multiprocessor Operating System (RTMPOS) provides the user with a versatile, interactive means for loading, running, debugging and obtaining results from a multiprocessor based simulator. A front end processor (FEP) serves as the simulator controller and interface between the user and the simulator. These functions are facilitated by the RTMPOS which resides on the FEP. The RTMPOS acts in conjunction with the FEP's manufacturer supplied disk operating system that provides typical utilities like an assembler, linkage editor, text editor, file handling services, etc. Once a simulation is formulated, the RTMPOS provides for engineering level, run time operations such as loading, modifying and specifying computation flow of programs, simulator mode control, data handling and run time monitoring. Run time monitoring is a powerful feature of RTMPOS that allows the user to record all actions taken during a simulation session and to receive advisories from the simulator via the FEP. The RTMPOS is programmed mainly in PASCAL along with some assembly language routines. The RTMPOS software is easily modified to be applicable to hardware from different manufacturers.

The density of states for almost periodic Schroedinger operators and the frequency module: a counter-example

International Nuclear Information System (INIS)

Bellissard, J.

1981-07-01

We exhibit an example of a one-dimensional discrete Schroedinger operator with an almost periodic potential for which the steps of the density of states do not belong to the frequency module. This example is suggested by the K-theory

Experience on operational safety improvement of control and operation support systems

International Nuclear Information System (INIS)

Itoh, N.; Nakagawa, T.; Mano, K.

1988-01-01

Japanese nuclear industry started in 1956 and about 30 years have passed since that time. Through these years, we have made a lot of efforts and developments in the field of Control and Instrumentation (C and I) system. The above 30 years and following years can be divided into four major periods. The first one is the period of research, the second of domestic production, the third of improvement, and the fourth of advancement. Improvements of C and I system, which we have made in those periods have made a great contribution to enhancement of reliability, availability and operability of nuclear power plants. Fig. 1 shows TEPCO's nuclear power plant (BWR) construction experience and technical trend of C and I system in Japan. This paper is to introduce the efforts and operational experience on control and operation support systems

Assessment of operative times of multiple surgical specialties in a public university hospital.

Science.gov (United States)

Costa, Altair da Silva

2017-01-01

To evaluate the indicators duration of anesthesia, operative time and time patients stay in the operating rooms of different surgical specialties at a public university hospital. It was done by a descriptive cross-sectional study based on the operating room database. The following stages were measured: duration of anesthesia, procedure time and patient length of stay in the room of the various specialties. We included surgeries carried out in sequence in the same room, between 7:00 a.m. and 5 p.m., either elective or emergency. We calculated the 80th percentile of the stages, where 80% of procedures were below this value. The study measured 8,337 operations of 12 surgical specialties performed within one year. The overall mean duration of anesthesia of all specialties was 178.12±110.46 minutes, and the 80th percentile was 252 minutes. The mean operative time was 130.45±97.23 minutes, and the 80th percentile was 195 minutes. The mean total time of the patient in the operating room was 197.30±113.71 minutes, and the 80th percentile was 285 minutes. Thus, the variation of the overall mean compared to the 80th percentile was 41% for anesthesia, 49% for surgeries and 44% for operating room time. In average, anesthesia took up 88% of the operating room period, and surgery, 61%. This study identified patterns in the duration of surgery stages. The mean values of the specialties can assist with operating room planning and reduce delays. Avaliar os indicadores de tempo da anestesia, da operação e da permanência do paciente em sala de diversas especialidades do centro cirúrgico de um hospital universitário. Foi realizado em estudo descritivo transversal a partir da base de dados do centro cirúrgico e mensuradas as seguintes etapas: duração de anestesia, tempo do procedimento e tempo de permanência do paciente em sala das diversas especialidades. Foram incluídas as operações realizadas em sequência na mesma sala, das 7h às 17h, eletivas ou de urg

Application of Periodic 3DPCM for Core Monitoring System

International Nuclear Information System (INIS)

Jeong, Wi-Soo; Lee, Hae-Chan; Kim, Hyeong-Seog; Lee, Chang-Kue; Park, Sang-weon; Baek, Jin-su

2014-01-01

The OASIS (Online core Analysis and Simulation System) was developed for WH type PWR which has movable in-core detector. 3DPCM (3D Power Connection Method) was also developed to measure 3D core power distribution using the fixed in-core detector signals and tested for KSNP (Korea Standard Nuclear Plant) such as OPR1000 and APR1400. According to previous study, 3DPCM coupling with neutronics code shows high accuracy. However, this method requires the neutronics code results at each calculation. Therefore, the long calculation time makes it impractical in the online monitoring system requiring the real-time 3D power distribution. In this paper, the 3DPCM based alternative methodology which called periodic 3DPCM is proposed to reduce the calculation time within the reasonable accuracy. The periodic 3DPCM is proposed to reduce the number of neutronics calculation with reasonable accuracy for the application to the online monitoring system development. The periodic 3DPCM is analyzed by 3 cases of sensitivity studies. The errors for the results of power changing operation, ASI changing simulation, and lead control rod insertion are bounded in 0.25%, 1.07%, and 1.15%, respectively. If the update time is shorten as 1 hour, the errors for power changing operation and ASI changing simulation are bounded in 0.07% and 0.56%, respectively. As a result, the update time of 1 hour and prompt update at 30% control rod position change are reasonable considering both conservativeness and effectiveness to update the prediction values. OASIS program utilizing periodic 3DPCM is verified using the plant measurement data and snapshot files which were generated during 45 days operation

Plant operation state monitoring system

International Nuclear Information System (INIS)

Sakai, Masanori; Babuchi, Katsumi; Arato, Toshiaki

1994-01-01

The system of the present invention accurately monitors a plant operation state of a plant, such as a nuclear power plant and a thermal power plant by using high temperature water, based on water quality informations. That is, water quality informations for the objective portion by using an electrochemical water quality sensor disposed in the objective portion to be monitored in the plant are continuously extracted for a predetermined period of time. Water quality is evaluated based on the extracted information. Obtained results for water quality evaluation and predetermined reference values of the plant operation handling are compared. Necessary part among the results of the measurement is displayed or recorded. The predetermined period of time described above is a period that the water quality information reaches at least a predetermined value or a period that the predetermined value is estimated by the water quality information, and it is defined as a period capable of measuring the information for three months continuously. The measurement is preferably conducted continuously in a period up to each periodical inspection on about every one year. (I.S.)

Sensitivity of Hurst parameter estimation to periodic signals in time series and filtering approaches

Science.gov (United States)

Marković, D.; Koch, M.

2005-09-01

The influence of the periodic signals in time series on the Hurst parameter estimate is investigated with temporal, spectral and time-scale methods. The Hurst parameter estimates of the simulated periodic time series with a white noise background show a high sensitivity on the signal to noise ratio and for some methods, also on the data length used. The analysis is then carried on to the investigation of extreme monthly river flows of the Elbe River (Dresden) and of the Rhine River (Kaub). Effects of removing the periodic components employing different filtering approaches are discussed and it is shown that such procedures are a prerequisite for an unbiased estimation of H. In summary, our results imply that the first step in a time series long-correlation study should be the separation of the deterministic components from the stochastic ones. Otherwise wrong conclusions concerning possible memory effects may be drawn.

Response times of operators in a control room

International Nuclear Information System (INIS)

Platz, O.; Rasmussen, J.; Skanborg, P.Z.

1982-12-01

A statistical analysis was made of operator response times recorded in the control room of a research reactor during the years 1972-1974. A homogeneity test revealed that the data consist of a mixture of populations. A small but statistically significant difference is found between day and night response times. Lognormal distributions are found to provide the best fit of the day and the night response times. (author)

The Improved Adaptive Silence Period Algorithm over Time-Variant Channels in the Cognitive Radio System

Directory of Open Access Journals (Sweden)

Jingbo Zhang

2018-01-01

Full Text Available In the field of cognitive radio spectrum sensing, the adaptive silence period management mechanism (ASPM has improved the problem of the low time-resource utilization rate of the traditional silence period management mechanism (TSPM. However, in the case of the low signal-to-noise ratio (SNR, the ASPM algorithm will increase the probability of missed detection for the primary user (PU. Focusing on this problem, this paper proposes an improved adaptive silence period management (IA-SPM algorithm which can adaptively adjust the sensing parameters of the current period in combination with the feedback information from the data communication with the sensing results of the previous period. The feedback information in the channel is achieved with frequency resources rather than time resources in order to adapt to the parameter change in the time-varying channel. The Monte Carlo simulation results show that the detection probability of the IA-SPM is 10–15% higher than that of the ASPM under low SNR conditions.

Finite-Difference Time-Domain Simulation of Light Propagation in 2D Periodic and Quasi-Periodic Photonic Structures

Directory of Open Access Journals (Sweden)

N. Dadashzadeh

2013-09-01

Full Text Available Ultra-short pulse is a promising technology for achieving ultra-high data rate transmission which is required to follow the increased demand of data transport over an optical communication system. Therefore, the propagation of such type of pulses and the effects that it may suffer during its transmission through an optical waveguide has received a great deal of attention in the recent years. We provide an overview of recent theoretical developments in a numerical modeling of Maxwell's equations to analyze the propagation of short laser pulses in photonic structures. The process of short light pulse propagation through 2D periodic and quasi-periodic photonic structures is simulated based on Finite-Difference Time-Domain calculations of Maxwell’s equations.

Boundedness and almost Periodicity in Time of Solutions of Evolutionary Variational Inequalities

Science.gov (United States)

Pankov, A. A.

1983-04-01

In this paper existence theorems are obtained for the solutions of abstract parabolic variational inequalities, which are bounded with respect to time (in the Stepanov and L^\\infty norms). The regularity and almost periodicity properties of such solutions are studied. Theorems are also established concerning their solvability in spaces of Besicovitch almost periodic functions. The majority of the results are obtained without any compactness assumptions. Bibliography: 30 titles.

Self-publishing of Lithuanian cultural periodicals in Soviet and contemporary times

Directory of Open Access Journals (Sweden)

Asta Urbanaviciute

2015-07-01

Full Text Available The aim of this article is to analyse self-publishing trends of Lithuanian cultural periodicals focusing on the historical and contemporary contexts. The article provides an overview of the reasons for historical cultural periodical self-published texts, known as samizdats, to appear, as well as their publishing and circulation trends in Lithuania. It also analyses what contemporary cultural self-publishing is: whether it is a completely independent, logical consequence of the digital age, which emerged under favourable circumstances, or if it can be characterized as having something in common with the past experiences. The most active years of the periodical underground press publishing in Soviet Lithuanian self-publishing development were between 1975 and 1981. Self-published texts ideologically diverged into three main directions: religious, civic, and cultural-artistic. A total of 22 publications were being published for a longer or shorter period of time. While analysing contemporary cultural self-publishing topics, the report focuses only on online cultural texts, irrespective of the printed ones. Survey method was used to find out how much and in what aspect modern Internet users perceive historical periodical self-publishing, and how and in what aspect they value modern cultural self-published texts. The results show that 18-35-year-old respondents have not acquired the skills necessary to analyse samizdat publishing. They associate the word self-publishing with digital texts only, which due to favourable conditions spread easily through social networks and blogs. In the era of advancing computer technologies and the Internet, every person who has the time and desire may become a developer, an author, or at least a disseminator of information: this tradition is becoming more and more topical and quite frequently – an almost self-evident phenomenon.

Investigation of unstable periodic space-time states in distributed active system with supercritical current

International Nuclear Information System (INIS)

Koronovskij, A.A.; Rempen, I.S.; Khramov, A.E.

2003-01-01

The set of the unstable periodic space-time states, characterizing the chaotic space-time dynamics of the electron beam with the supercritical current in the Pierce diode is discussed. The Lyapunov indicators of the revealed instable space-time states of the chaotic dynamics of the distributed self-excited system are calculated. It is shown that change in the set of the unstable periodic states in dependence on the Pierce parameter is determined by change in the various orbits stability, which is demonstrated by the values of senior Lyapunov unstable state index [ru

Relative blood loss and operative time can predict length of stay following orthognathic surgery.

Science.gov (United States)

Andersen, K; Thastum, M; Nørholt, S E; Blomlöf, J

2016-10-01

The aim of this study was to investigate the length of stay (LOS) following orthognathic surgery and thereby to establish a benchmark. The secondary aim was to identify predictors of postoperative LOS following orthognathic surgery. Patients were treated consecutively during the period 2010 to 2012. Inclusion criteria were (1) patient age ≥18 years, and (2) surgery involving a three-piece Le Fort I osteotomy, or a bilateral sagittal split osteotomy (BSSO), or bimaxillary surgery. A total of 335 patients were included. The following data were recorded: height, weight, body mass index (BMI), age, sex, operative time, intraoperative blood loss, and type of surgery. LOS was defined as the duration of time from date of surgery to date of discharge. The average LOS was 1.3 days following Le Fort I osteotomy, 1.3 days following BSSO, and 1.8 days following bimaxillary surgery. In the multivariate regression model (R(2)=0.11), predictors of a prolonged LOS were operative time (P<0.001) and relative blood loss (P=0.002). No significant effect of age, BMI, sex, or treatment on LOS was observed. The short duration of LOS found in this study supports the possibility of increasing outpatient pathways for selected patients. Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Real-time embedded systems open-source operating systems perspective

CERN Document Server

Bertolotti, Ivan Cibrario

2012-01-01

From the Foreword: "!the presentation of real-time scheduling is probably the best in terms of clarity I have ever read in the professional literature. Easy to understand, which is important for busy professionals keen to acquire (or refresh) new knowledge without being bogged down in a convoluted narrative and an excessive detail overload. The authors managed to largely avoid theoretical-only presentation of the subject, which frequently affects books on operating systems. ! an indispensable [resource] to gain a thorough understanding of the real-time systems from the operating systems p

Bounded and Periodic Solutions of Semilinear Impulsive Periodic System on Banach Spaces

Directory of Open Access Journals (Sweden)

Wei W

2008-01-01

Full Text Available Abstract A class of semilinear impulsive periodic system on Banach spaces is considered. First, we introduce the -periodic PC-mild solution of semilinear impulsive periodic system. By virtue of Gronwall lemma with impulse, the estimate on the PC-mild solutions is derived. The continuity and compactness of the new constructed Poincaré operator determined by impulsive evolution operator corresponding to homogenous linear impulsive periodic system are shown. This allows us to apply Horn's fixed-point theorem to prove the existence of -periodic PC-mild solutions when PC-mild solutions are ultimate bounded. This extends the study on periodic solutions of periodic system without impulse to periodic system with impulse on general Banach spaces. At last, an example is given for demonstration.

Practitioners' Perceptions of the Soccer Extra-Time Period: Implications for Future Research

OpenAIRE

Harper, Liam D.; Fothergill, Melissa; West, Daniel J.; Stevenson, Emma; Russell, Mark

2016-01-01

Qualitative research investigating soccer practitioners’ perceptions can allow researchers to create practical research investigations. The extra-time period of soccer is understudied compared to other areas of soccer research. Using an open-ended online survey containing eleven main and nine sub questions, we gathered the perceptions of extra-time from 46 soccer practitioners, all working for different professional soccer clubs. Questions related to current practices, views on extra-time reg...

The energy-momentum operator in curved space-time

International Nuclear Information System (INIS)

Brown, M.R.; Ottewill, A.C.

1983-01-01

It is argued that the only meaningful geometrical measure of the energy-momentum of states of matter described by a free quantum field theory in a general curved space-time is that provided by a normal ordered energy-momentum operator. The finite expectation values of this operator are contrasted with the conventional renormalized expectation values and it is further argued that the use of renormalization theory is inappropriate in this context. (author)

Optimisation of battery operating life considering software tasks and their timing behaviour

Energy Technology Data Exchange (ETDEWEB)

Lipskoch, Henrik

2010-02-19

, either global, for all tasks, or local, individually per task. It is shown that a global slowdown factor can be computed from the linear constraints together with a linear objective in a linear program, whereas local slowdown factors are shown to require a non-linear but still convex objective. Processor shutdown switches off the processor for a specific time; it blocks the processor from processing software. Duration and occurrence become optimisation parameters, and the linearised real-time feasibility test is used to decide whether a parameter setting is feasible or violates deadlines. In this thesis, two shutdown policies are introduced. Periodic shutdown switches off the processor periodically, thus, besides duration, the period is to be optimised. Task-dependent shutdown switches off the processor with an inherited occurrence behaviour from a certain task, thus, besides duration, the parent task needs to be chosen, as well as the number of instances of the parent task to fall between two consecutive shutdowns. Each of the presented methods for saving energy yields a different system configuration, out of which the best with respect to operating life is chosen with the help of a battery model. Discharge profiles serve as a coupling between information in the notion of event streams, task power consumptions, and the battery model. A battery model evaluation with measurements is presented in this thesis. [German] Benutzer mobiler eingebetteter Systeme haben ein Interesse an einer langen Batterienutzungsdauer. Je laenger ein System ohne Nachladen oder Batteriewechsel operieren kann, desto geringer werden Wartungskosten und durch Energiemangel bedingte Ausfaelle. Energiesparmethoden helfen die Nutzungsdauer zu verlaengern, koennen jedoch zu einer Reduzierung der verfuegbaren Rechenzeit fuehren. Die Systeme koennen zeitlichen Anforderungen unterworfen sein, etwa um eine zuverlaessige Kommunikation sicherzustellen. Somit ist der Einsatz von Energiesparmethoden neben der

Detection of Quasi-Periodic Pulsations in Solar EUV Time Series

Science.gov (United States)

Dominique, M.; Zhukov, A. N.; Dolla, L.; Inglis, A.; Lapenta, G.

2018-04-01

Quasi-periodic pulsations (QPPs) are intrinsically connected to the mechanism of solar flares. They are regularly observed in the impulsive phase of flares since the 1970s. In the past years, the studies of QPPs regained interest with the advent of a new generation of soft X-ray/extreme ultraviolet radiometers that pave the way for statistical surveys. Since the amplitude of QPPs in these wavelengths is rather small, detecting them implies that the overall trend of the time series needs to be removed before applying any Fourier or wavelet transform. This detrending process is known to produce artificial detection of periods that must then be distinguished from real ones. In this paper, we propose a set of criteria to help identify real periods and discard artifacts. We apply these criteria to data taken by the Extreme Ultraviolet Variability Experiment (EVE)/ESP onboard the Solar Dynamics Observatory (SDO) and the Large Yield Radiometer (LYRA) onboard the PRoject for On-Board Autonomy 2 (PROBA2) to search for QPPs in flares stronger than M5.0 that occurred during Solar Cycle 24.

Higher pressure periodic CO/sub 2/ laser with non-self-sustaining discharge and UV ionization

Energy Technology Data Exchange (ETDEWEB)

Muratov, E A; Pismennyi, V D; Rakhimov, A T

1979-02-01

Stimulated emission was achieved in a CO/sub 2/ laser operating at 250 torr excited by a periodic non-self-sustaining discharge controlled by a spark source of UV radiation. Use of a UV source operating in periodic pulse regime is shown to permit quasicontinuous operation of the laser with characteristic radiating times up to several hundred microseconds.

A statistical forecast model using the time-scale decomposition technique to predict rainfall during flood period over the middle and lower reaches of the Yangtze River Valley

Science.gov (United States)

Hu, Yijia; Zhong, Zhong; Zhu, Yimin; Ha, Yao

2018-04-01

In this paper, a statistical forecast model using the time-scale decomposition method is established to do the seasonal prediction of the rainfall during flood period (FPR) over the middle and lower reaches of the Yangtze River Valley (MLYRV). This method decomposites the rainfall over the MLYRV into three time-scale components, namely, the interannual component with the period less than 8 years, the interdecadal component with the period from 8 to 30 years, and the interdecadal component with the period larger than 30 years. Then, the predictors are selected for the three time-scale components of FPR through the correlation analysis. At last, a statistical forecast model is established using the multiple linear regression technique to predict the three time-scale components of the FPR, respectively. The results show that this forecast model can capture the interannual and interdecadal variation of FPR. The hindcast of FPR during 14 years from 2001 to 2014 shows that the FPR can be predicted successfully in 11 out of the 14 years. This forecast model performs better than the model using traditional scheme without time-scale decomposition. Therefore, the statistical forecast model using the time-scale decomposition technique has good skills and application value in the operational prediction of FPR over the MLYRV.

Automated Periodicals System at a Community College Library

Directory of Open Access Journals (Sweden)

Vivian Harp

1974-06-01

Full Text Available Automated systems need not be extensive to save time and improve efficiency. Moraine Valley's off-line operation, based on a file of 715 periodical titles, generates renewal orders, sends claims, and records subscription histories.

A battery-operated pilot balloon time-signal generator

Science.gov (United States)

Ralph H. Moltzau

1966-01-01

Describes the design and construction of a 1-pound, battery-operated, time-signal transmitter, which is usable with portable radio or field telephone circuits for synchronizing multi-theodolite observation of pilot balloons.

Determination operation Time Risk of Box Spinning Components-oe Spinning Machine

OpenAIRE

Slobodan Stefanovic

2013-01-01

Based on the constructed dependency diagram reliability of the exploitation operation time of each constituent components of the analyzed frame in the case of selected statistical distributions, areas of the operation exploitation and repair intervals are determined. This is done by determining the first inflection points. Based on these points analysis to determine the time of safety operation of frame components with allowable risk to the segmental linear function of the intensity of failur...

Succinct Dynamic Cardinal Trees with Constant Time Operations for Small Alphabet

DEFF Research Database (Denmark)

Davoodi, Pooya; Satti, Srinivasa Rao

2011-01-01

) bits and performs the following operations in O(1) time: parent, child(i), label-child(alpha), degree, subtree-size, preorder, is-ancestor(x), insert-leaf (alpha), delete-leaf(alpha). The update times are amortized. The space is close to the information theoretic lower bound. The operations...

MINIX4RT: a real-time operating system based on MINIX

OpenAIRE

Pessolani, Pablo Andrés

2006-01-01

Tanenbaum's MINIX Operating System was extended with a Real-Time microkernel and services to conform MINIX4RT, a Real-Time Operating System for academic uses that includes more flexible Interprocess Communications facilities supporting basic priority inheritance protocol, a fixed priority scheduler, timer and event driven interrupt management, statistics and Real-Time metrics gathering keeping backward compatibility with standard MINIX versions. Facultad de Informática

Operation of beam line facilities for real-time x-ray studies at Sector 7 of the advanced photon source. Final Report

International Nuclear Information System (INIS)

Clarke, Roy

2003-01-01

This Final Report documents the research accomplishments achieved in the first phase of operations of a new Advanced Photon Source beam line (7-ID MHATT-CAT) dedicated to real-time x-ray studies. The period covered by this report covers the establishment of a world-class facility for time-dependent x-ray studies of materials. During this period many new and innovative research programs were initiated at Sector 7 with support of this grant, most notably using a combination of ultrafast lasers and pulsed synchrotron radiation. This work initiated a new frontier of materials research: namely, the study of the dynamics of materials under extreme conditions of high intensity impulsive laser irradiation

Koopman Operator Framework for Time Series Modeling and Analysis

Science.gov (United States)

Surana, Amit

2018-01-01

We propose an interdisciplinary framework for time series classification, forecasting, and anomaly detection by combining concepts from Koopman operator theory, machine learning, and linear systems and control theory. At the core of this framework is nonlinear dynamic generative modeling of time series using the Koopman operator which is an infinite-dimensional but linear operator. Rather than working with the underlying nonlinear model, we propose two simpler linear representations or model forms based on Koopman spectral properties. We show that these model forms are invariants of the generative model and can be readily identified directly from data using techniques for computing Koopman spectral properties without requiring the explicit knowledge of the generative model. We also introduce different notions of distances on the space of such model forms which is essential for model comparison/clustering. We employ the space of Koopman model forms equipped with distance in conjunction with classical machine learning techniques to develop a framework for automatic feature generation for time series classification. The forecasting/anomaly detection framework is based on using Koopman model forms along with classical linear systems and control approaches. We demonstrate the proposed framework for human activity classification, and for time series forecasting/anomaly detection in power grid application.

Extending the maximum operation time of the MNSR reactor.

Science.gov (United States)

Dawahra, S; Khattab, K; Saba, G

2016-09-01

An effective modification to extend the maximum operation time of the Miniature Neutron Source Reactor (MNSR) to enhance the utilization of the reactor has been tested using the MCNP4C code. This modification consisted of inserting manually in each of the reactor inner irradiation tube a chain of three polyethylene-connected containers filled of water. The total height of the chain was 11.5cm. The replacement of the actual cadmium absorber with B(10) absorber was needed as well. The rest of the core structure materials and dimensions remained unchanged. A 3-D neutronic model with the new modifications was developed to compare the neutronic parameters of the old and modified cores. The results of the old and modified core excess reactivities (ρex) were: 3.954, 6.241 mk respectively. The maximum reactor operation times were: 428, 1025min and the safety reactivity factors were: 1.654 and 1.595 respectively. Therefore, a 139% increase in the maximum reactor operation time was noticed for the modified core. This increase enhanced the utilization of the MNSR reactor to conduct a long time irradiation of the unknown samples using the NAA technique and increase the amount of radioisotope production in the reactor. Copyright © 2016 Elsevier Ltd. All rights reserved.

17 CFR 260.7a-24 - Words relating to periods of time in the past.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Words relating to periods of time in the past. 260.7a-24 Section 260.7a-24 Commodity and Securities Exchanges SECURITIES AND... Requirements As to Contents § 260.7a-24 Words relating to periods of time in the past. Unless the context...

The HAL 9000 Space Operating System Real-Time Planning Engine Design and Operations Requirements

Science.gov (United States)

Stetson, Howard; Watson, Michael D.; Shaughnessy, Ray

2012-01-01

In support of future deep space manned missions, an autonomous/automated vehicle, providing crew autonomy and an autonomous response planning system, will be required due to the light time delays in communication. Vehicle capabilities as a whole must provide for tactical response to vehicle system failures and space environmental effects induced failures, for risk mitigation of permanent loss of communication with Earth, and for assured crew return capabilities. The complexity of human rated space systems and the limited crew sizes and crew skills mix drive the need for a robust autonomous capability on-board the vehicle. The HAL 9000 Space Operating System[2] designed for such missions and space craft includes the first distributed real-time planning / re-planning system. This paper will detail the software architecture of the multiple planning engine system, and the interface design for plan changes, approval and implementation that is performed autonomously. Operations scenarios will be defined for analysis of the planning engines operations and its requirements for nominal / off nominal activities. An assessment of the distributed realtime re-planning system, in the defined operations environment, will be provided as well as findings as it pertains to the vehicle, crew, and mission control requirements needed for implementation.

Pulse counting period meter output during startup transients

International Nuclear Information System (INIS)

Cummins, J.D.

1962-12-01

The time response of a period meter whose input signal comes from a pulse counting channel may be calculated using a Ferranti Mercury autocode programme details of which are given. The period meter considered is the type for which the logarithmic characteristic is approximated by several diode pump circuits. The input excitation is a terminated ramp of reactivity. Other reactivity inputs may be treated. In particular the step change of reactivity may be used as the input excitation. Allowance is made for the effective time constants of the diode pump circuits and the period meter. The programme may be used for instrument assessment and for safety and operations studies on reactors which use this type of period meter. An example of the use of the programme is given. (author)

Tracing temperature in a nanometer size region in a picosecond time period.

Science.gov (United States)

Nakajima, Kaoru; Kitayama, Takumi; Hayashi, Hiroaki; Matsuda, Makoto; Sataka, Masao; Tsujimoto, Masahiko; Toulemonde, Marcel; Bouffard, Serge; Kimura, Kenji

2015-08-21

Irradiation of materials with either swift heavy ions or slow highly charged ions leads to ultrafast heating on a timescale of several picosecond in a region of several nanometer. This ultrafast local heating result in formation of nanostructures, which provide a number of potential applications in nanotechnologies. These nanostructures are believed to be formed when the local temperature rises beyond the melting or boiling point of the material. Conventional techniques, however, are not applicable to measure temperature in such a localized region in a short time period. Here, we propose a novel method for tracing temperature in a nanometer region in a picosecond time period by utilizing desorption of gold nanoparticles around the ion impact position. The feasibility is examined by comparing with the temperature evolution predicted by a theoretical model.

Nutrition for the pediatric surgical patient: approach in the peri-operative period

Directory of Open Access Journals (Sweden)

Falcão Mário Cícero

2002-01-01

Full Text Available Nutrition is essential for maintenance of physiologic homeostasis and growth. Hypermetabolic states lead to a depletion of body stores, with decreased immunocompetence and increased morbidity and mortality. The purpose of this paper is to provide an update regarding the provision of appropriate nutrition for the pediatric surgical patient, emphasizing the preoperative and postoperative periods. Modern nutritional support for the surgical patient comprises numerous stages, including assessment of nutritional status, nutritional requirements, and nutritional therapy. Nutritional assessment is performed utilizing the clinical history, clinical examination, anthropometry, and biochemical evaluation. Anthropometric parameters include body weight, height, arm and head circumference, and skinfold thickness measurements. The biochemical evaluation is conducted using determinations of plasma levels of proteins, including album, pre-albumin, transferrin, and retinol-binding protein. These parameters are subject to error and are influenced by the rapid changes in body composition in the peri-operative period. Nutritional therapy includes enteral and/or parenteral nutrition. Enteral feeding is the first choice for nutritional therapy. If enteral feeding is not indicated, parenteral nutrition must be utilized. In all cases, an individualized, adequate diet (enteral formula or parenteral solution is obligatory to decrease the occurrence of overfeeding and its undesirable consequences.

The Periodization of Fighting on Donbass in 2014–2015 years

Directory of Open Access Journals (Sweden)

Nikolai V. Mityukov

2016-03-01

Full Text Available The article based on the analysis of the data gives the attempt of the periodical press of combat actions on the territory of Donbas in 2014-2015: there are presented clearly two periods. The first is the period of the maneuvers from 7 April 2014 to 5 September 2014, characterized by the presence of fortified centres which both sides tried to get around to entering the operating room. In this period there is no clear front line, fighting was an interaction maneuverable shock groups. The second period is the period position of action from September 5 to the present time, characterized by clearly formed the front line, as a rule, deeply echeloned. Active hostilities reached a peak during the battle for Lugansk and the Donetsk airport and Debaltsevo during the operation.

Feynman's operational calculus and beyond noncommutativity and time-ordering

CERN Document Server

Johnson, George W; Nielsen, Lance

2015-01-01

This book is aimed at providing a coherent, essentially self-contained, rigorous and comprehensive abstract theory of Feynman's operational calculus for noncommuting operators. Although it is inspired by Feynman's original heuristic suggestions and time-ordering rules in his seminal 1951 paper An operator calculus having applications in quantum electrodynamics, as will be made abundantly clear in the introduction (Chapter 1) and elsewhere in the text, the theory developed in this book also goes well beyond them in a number of directions which were not anticipated in Feynman's work. Hence, the second part of the main title of this book. The basic properties of the operational calculus are developed and certain algebraic and analytic properties of the operational calculus are explored. Also, the operational calculus will be seen to possess some pleasant stability properties. Furthermore, an evolution equation and a generalized integral equation obeyed by the operational calculus are discussed and connections wi...

40 CFR 73.18 - Submittal procedures for units commencing commercial operation during the period from January 1...

Science.gov (United States)

2010-07-01

... commencing commercial operation during the period from January 1, 1993, through December 31, 1995. 73.18 Section 73.18 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) SULFUR DIOXIDE ALLOWANCE SYSTEM Allowance Allocations § 73.18 Submittal procedures for units...

Alpha: A real-time decentralized operating system for mission-oriented system integration and operation

Science.gov (United States)

Jensen, E. Douglas

1988-01-01

Alpha is a new kind of operating system that is unique in two highly significant ways. First, it is decentralized transparently providing reliable resource management across physically dispersed nodes, so that distributed applications programming can be done largely as though it were centralized. And second, it provides comprehensive, high technology support for real-time system integration and operation, an application area which consists predominately of aperiodic activities having critical time constraints such as deadlines. Alpha is extremely adaptable so that it can be easily optimized for a wide range of problem-specific functionality, performance, and cost. Alpha is the first systems effort of the Archons Project, and the prototype was created at Carnegie-Mellon University directly on modified Sun multiprocessor workstation hardware. It has been demonstrated with a real-time C(sup 2) application. Continuing research is leading to a series of enhanced follow-ons to Alpha; these are portable but initially hosted on Concurrent's MASSCOMP line of multiprocessor products.

Monostable traveling waves for a time-periodic and delayed nonlocal reaction-diffusion equation

Science.gov (United States)

Li, Panxiao; Wu, Shi-Liang

2018-04-01

This paper is concerned with a time-periodic and delayed nonlocal reaction-diffusion population model with monostable nonlinearity. Under quasi-monotone or non-quasi-monotone assumptions, it is known that there exists a critical wave speed c_*>0 such that a periodic traveling wave exists if and only if the wave speed is above c_*. In this paper, we first prove the uniqueness of non-critical periodic traveling waves regardless of whether the model is quasi-monotone or not. Further, in the quasi-monotone case, we establish the exponential stability of non-critical periodic traveling fronts. Finally, we illustrate the main results by discussing two types of death and birth functions arising from population biology.

Optimizing the space-time-yield and the specific energy consumption of molten salt electrolysis processes for the electrowinning of metals in subgroups 4 and 5 of the periodic table of elements

International Nuclear Information System (INIS)

Koeck, W.

1988-04-01

Disadvantages of molten salt electrolysis are its low space-time-yield (kg/m 3 h) combined with its high specific energy consumption (kWh/kg). These factors essentially determine how electrolysis is applied on an industrial scale. The electrolysis of tantalum was selected as an example representative for other electrolytic processes; this series of tests allow statements also on the winning of the other elements from subgroups 4 and 5 of the periodic table, and on electrolytic aluminium extraction. Optimal operating conditions for direct current electrolysis were determined in the laboratory by varying the current density and the electrolysis temperature. In order to improve the space-time-yield from an existing electrolytic cell with a given electrolyte composition beyond the optimal range of direct current electrolysis, the process of periodic current reversal is applied. In this process, the polarity is reversed for a short time at constant periodic intervals. If the forward time period and the backward time period are chosen in a suitable way, both the current efficiency and the space-time-yield can be improved without increasing the energy consumption. 59 refs., 48 figs., 8 tabs. (Author)

NPP Krsko Periodic Safety Review action plan

International Nuclear Information System (INIS)

Bilic Zabric, T.

2006-01-01

In the current, internationally accepted, safety philosophy Periodic Safety Reviews (PSRs) are comprehensive reviews aimed at the verification that an operating NPP remains safe when judged against current safety objectives and practices and that adequate arrangements are in place to maintain an acceptable level of safety. These reviews are complementary to the routine and special safety reviews. They are long time-scale reviews intended to deal with the cumulative effects of plant ageing, modifications, operating experience and technical developments, which are not so easily comprehended over the shorter time-scale routine of safety reviews. The review was completed in 2005 and the next period will see the implementation of the action plan including some plant upgrades. The action plan lists issues that should be implemented at NPP Krsko together with associated milestones. The milestones were assumed based on best estimate resource availability and their ends can be potentially floated. In some cases, multiple corrective measures may be postulated to provide resolution for a given safety issue. The Slovenian Nuclear Safety Administration by decree approved the first periodic safety review and the implementation plan of activities arising from it. The entire implementation plan must be carried out by 15 October 2010. Report on the second periodic safety review must be submitted by the NEK not later than 15 December 2013. (author)

Real-Time Plasma Control Tools for Advanced Tokamak Operation

International Nuclear Information System (INIS)

Varandas, C. A. F.; Sousa, J.; Rodrigues, A. P.; Carvalho, B. B.; Fernandes, H.; Batista, A. J.; Cruz, N.; Combo, A.; Pereira, R. C.

2006-01-01

Real-time control will play an important role in the operation and scientific exploitation of the new generation fusion devices. This paper summarizes the real-time systems and diagnostics developed by the Portuguese Fusion Euratom Association based on digital signal processors and field programmable gate arrays

Nonequilibrium steady states and resonant tunneling in time-periodically driven systems with interactions

Science.gov (United States)

Qin, Tao; Hofstetter, Walter

2018-03-01

Time-periodically driven systems are a versatile toolbox for realizing interesting effective Hamiltonians. Heating, caused by excitations to high-energy states, is a challenge for experiments. While most setups so far address the relatively weakly interacting regime, it is of general interest to study heating in strongly correlated systems. Using Floquet dynamical mean-field theory, we study nonequilibrium steady states (NESS) in the Falicov-Kimball model, with time-periodically driven kinetic energy or interaction. We systematically investigate the nonequilibrium properties of the NESS. For a driven kinetic energy, we show that resonant tunneling, where the interaction is an integer multiple of the driving frequency, plays an important role in the heating. In the strongly correlated regime, we show that this can be well understood using Fermi's golden rule and the Schrieffer-Wolff transformation for a time-periodically driven system. We furthermore demonstrate that resonant tunneling can be used to control the population of Floquet states to achieve "photodoping." For driven interactions introduced by an oscillating magnetic field near a widely adopted Feshbach resonance, we find that the double occupancy is strongly modulated. Our calculations apply to shaken ultracold-atom systems and to solid-state systems in a spatially uniform but time-dependent electric field. They are also closely related to lattice modulation spectroscopy. Our calculations are helpful to understand the latest experiments on strongly correlated Floquet systems.

Positive Almost Periodic Solutions for a Time-Varying Fishing Model with Delay

Directory of Open Access Journals (Sweden)

Xia Li

2011-01-01

Full Text Available This paper is concerned with a time-varying fishing model with delay. By means of the continuation theorem of coincidence degree theory, we prove that it has at least one positive almost periodic solution.

Beznau II nuclear power plant: Expertise on NOK's request for the removal of the time limitation for the operation licence

International Nuclear Information System (INIS)

2004-03-01

The Federal Agency for the Safety of Nuclear Installations (HSK) is the Swiss authority responsible for nuclear safety and protection against radioactivity in nuclear power plants. It has to examine the request of the North-East Swiss Power Corporation (NOK) concerning the removal of the operational time limitation for the Beznau-II reactor (KKB-II). In the present report HSK reviews the enterprise management and the safety of KKB-II on the basis of the results of the Periodic Safety Review. The Beznau nuclear power plant exhibits a very high degree of technical and organisational safety. During the past 10 years the plant has been operated in a safe manner. At the same time the plant has been improved and this guarantees that the mechanisms of ageing degradation are systematically identified and that measures can be taken that are possibly necessary. Under such conditions, the safety of KKB-II can be guarantied at all times. As a result of the management of quality, environmental and working safety conditions, the correct application and the continuous improvement of all processes important to safety are ensured. With these measures KKB has shown that safety is given priority over and against all other working goals. The examination by HSK of the Periodic Safety Review has shown that, in the past, KKB has applied modernisation measures independent of the licensing situation of the two reactor blocks. These modernisation measures largely contribute to the fact that the HSK examination did not reveal any significant safety deficiencies. Other improvement measures allow risk reduction or can bee seen as an adaptation to experience gained and to the state of the technological art. In conclusion, HSK states that no safety-relevant facts have been found which could prevent the removal of the time limitation on the operational licence for KKB-II. From the point of view of HSK, KKB-II fulfils the conditions for the safe continuation of operation

A Parallel Priority Queue with Constant Time Operations

DEFF Research Database (Denmark)

Brodal, Gerth Stølting; Träff, Jesper Larsson; Zaroliagis, Christos D.

1998-01-01

We present a parallel priority queue that supports the following operations in constant time:parallel insertionof a sequence of elements ordered according to key,parallel decrease keyfor a sequence of elements ordered according to key,deletion of the minimum key element, anddeletion of an arbitrary...... application is a parallel implementation of Dijkstra's algorithm for the single-source shortest path problem, which runs inO(n) time andO(mlogn) work on a CREW PRAM on graphs withnvertices andmedges. This is a logarithmic factor improvement in the running time compared with previous approaches....

Discreteness of the spectrum of some operator sheaves associated with a periodic Schroedinger equation

International Nuclear Information System (INIS)

Dyakin, V.V.; Petrukhnovskii, S.I.

1988-01-01

Three-dimensional periodic Schroedinger operators with potentials that are square integrable on the unit cell (single-electron model of a crystal) are considered. A description is given of the class of rational curves that do not have more than a finite number of common points with any isoenergy surface (in particular, the Fermi surface) of an arbitrary operator of the considered form. A consequence of a theorem proved in the paper is the absence on the isoenergy surfaces of elements of planes, cones, and cylinders with straight generators, and all possible paraboloids and hyperboloids. Another interesting consequence is the following assertion: The topological dimension of an isoenergy manifold does not exceed two, which justifies the use of the word surface. The results generalize the assertion of Thomas's theorem on the absence on isoenergy surfaces of straight edges

Revision of nuclear power plants safety systems' routine testing assigned periodicity during the design extension period

International Nuclear Information System (INIS)

Skalozubov, V.I.; Kozlov, Yi.L.; Chulkyin, O.O.

2017-01-01

When nuclear power plants safety systems thermal equipment operation extending, a necessary requirement shall rely on revising the scheduled equipment tests frequency to optimize those tests schedule taking into account the equipment remained lifespan. On the one hand, there exists a need for tests frequency increase to detect ''hidden'' failures, and on the another, frequent tests cause a premature wear of the equipment. Proposed is an original method for optimizing the frequency of NPPs safety systems thermal engineering equipment testing. Essential in the proposed method is the optimization criterion chosen: index of security system failure probability non-exceedance during the beyond-design operating period as referred to the failure probability expected considering the equipment residual resource during the design operating period. The developed method implementation when applied to NPPs safety systems operated beyond the design service life at nuclear power plants with WWER-1000 series reactors, allowed to establish that the optimal tests frequency makes half the designed one when the equipment service life is extended by five years and three times less that the designed frequency when subject lifespan extended by 10 years.

Optimisation of battery operating life considering software tasks and their timing behaviour

Energy Technology Data Exchange (ETDEWEB)

Lipskoch, Henrik

2010-02-19

optimisation variable, either global, for all tasks, or local, individually per task. It is shown that a global slowdown factor can be computed from the linear constraints together with a linear objective in a linear program, whereas local slowdown factors are shown to require a non-linear but still convex objective. Processor shutdown switches off the processor for a specific time; it blocks the processor from processing software. Duration and occurrence become optimisation parameters, and the linearised real-time feasibility test is used to decide whether a parameter setting is feasible or violates deadlines. In this thesis, two shutdown policies are introduced. Periodic shutdown switches off the processor periodically, thus, besides duration, the period is to be optimised. Task-dependent shutdown switches off the processor with an inherited occurrence behaviour from a certain task, thus, besides duration, the parent task needs to be chosen, as well as the number of instances of the parent task to fall between two consecutive shutdowns. Each of the presented methods for saving energy yields a different system configuration, out of which the best with respect to operating life is chosen with the help of a battery model. Discharge profiles serve as a coupling between information in the notion of event streams, task power consumptions, and the battery model. A battery model evaluation with measurements is presented in this thesis. [German] Benutzer mobiler eingebetteter Systeme haben ein Interesse an einer langen Batterienutzungsdauer. Je laenger ein System ohne Nachladen oder Batteriewechsel operieren kann, desto geringer werden Wartungskosten und durch Energiemangel bedingte Ausfaelle. Energiesparmethoden helfen die Nutzungsdauer zu verlaengern, koennen jedoch zu einer Reduzierung der verfuegbaren Rechenzeit fuehren. Die Systeme koennen zeitlichen Anforderungen unterworfen sein, etwa um eine zuverlaessige Kommunikation sicherzustellen. Somit ist der Einsatz von

Natural convection in square enclosure induced by inner circular cylinder with time-periodic pulsating temperature

KAUST Repository

Huang, Zhu; Zhang, Wei; Xi, Guang

2015-01-01

The periodic unsteady natural convection flow and heat transfer in a square enclosure containing a concentric circular cylinder is numerically studied. The temperature of the inner circular cylinder fluctuates periodically with time at higher

Storing quantum information in XXZ spin rings with periodically time-controlled interactions

International Nuclear Information System (INIS)

Giampaolo, S M; Illuminati, F; Mazzarella, G

2005-01-01

We introduce a general scheme to realize massive quantum memories in simple systems of interacting qubits. Such systems are described by spin rings with XXZ intersite couplings of suitably time-periodically controlled amplitudes. We show that initially localized excitations undergo perfect periodic revivals, allowing for the simultaneous storage of arbitrary sets of different local states. This novel approach to the problem of storing quantum information hints at a new way to control and suppress the effect of decoherence on a quantum computer realized in a system with nonvanishing interactions between the constituent qubits

Storing quantum information in XXZ spin rings with periodically time-controlled interactions

Energy Technology Data Exchange (ETDEWEB)

Giampaolo, S M; Illuminati, F; Mazzarella, G [Dipartimento di Fisica ' E. R. Caianiello' , Universita di Salerno, INFM UdR di Salerno, INFN Sezione di Napoli, Gruppo Collegato di Salerno, Via S. Allende, 84081 Baronissi, SA (Italy)

2005-10-01

We introduce a general scheme to realize massive quantum memories in simple systems of interacting qubits. Such systems are described by spin rings with XXZ intersite couplings of suitably time-periodically controlled amplitudes. We show that initially localized excitations undergo perfect periodic revivals, allowing for the simultaneous storage of arbitrary sets of different local states. This novel approach to the problem of storing quantum information hints at a new way to control and suppress the effect of decoherence on a quantum computer realized in a system with nonvanishing interactions between the constituent qubits.

Periodic review inventory policy for non-instantaneous deteriorating items with time dependent deterioration rate

Directory of Open Access Journals (Sweden)

Anwesha Samanta

2015-09-01

Full Text Available The paper studies a periodic review inventory model with no shortages and different demand rates during pre- and post- deterioration periods . Deterioration of units start after a fixed time interval, and the deterioration rate is time dependent. The model determines the optimal reorder interval and the optimal order quantity so as to minimize the total cost per unit length of an inventory cycle. An extension of the model to include price discount has been further considered. Numerical examples are presented to illustrate the model and a sensitivity analysis is also reported.

Simultaneous bilateral stereotactic procedure for deep brain stimulation implants: a significant step for reducing operation time.

Science.gov (United States)

Fonoff, Erich Talamoni; Azevedo, Angelo; Angelos, Jairo Silva Dos; Martinez, Raquel Chacon Ruiz; Navarro, Jessie; Reis, Paul Rodrigo; Sepulveda, Miguel Ernesto San Martin; Cury, Rubens Gisbert; Ghilardi, Maria Gabriela Dos Santos; Teixeira, Manoel Jacobsen; Lopez, William Omar Contreras

2016-07-01

OBJECT Currently, bilateral procedures involve 2 sequential implants in each of the hemispheres. The present report demonstrates the feasibility of simultaneous bilateral procedures during the implantation of deep brain stimulation (DBS) leads. METHODS Fifty-seven patients with movement disorders underwent bilateral DBS implantation in the same study period. The authors compared the time required for the surgical implantation of deep brain electrodes in 2 randomly assigned groups. One group of 28 patients underwent traditional sequential electrode implantation, and the other 29 patients underwent simultaneous bilateral implantation. Clinical outcomes of the patients with Parkinson's disease (PD) who had undergone DBS implantation of the subthalamic nucleus using either of the 2 techniques were compared. RESULTS Overall, a reduction of 38.51% in total operating time for the simultaneous bilateral group (136.4 ± 20.93 minutes) as compared with that for the traditional consecutive approach (220.3 ± 27.58 minutes) was observed. Regarding clinical outcomes in the PD patients who underwent subthalamic nucleus DBS implantation, comparing the preoperative off-medication condition with the off-medication/on-stimulation condition 1 year after the surgery in both procedure groups, there was a mean 47.8% ± 9.5% improvement in the Unified Parkinson's Disease Rating Scale Part III (UPDRS-III) score in the simultaneous group, while the sequential group experienced 47.5% ± 15.8% improvement (p = 0.96). Moreover, a marked reduction in the levodopa-equivalent dose from preoperatively to postoperatively was similar in these 2 groups. The simultaneous bilateral procedure presented major advantages over the traditional sequential approach, with a shorter total operating time. CONCLUSIONS A simultaneous stereotactic approach significantly reduces the operation time in bilateral DBS procedures, resulting in decreased microrecording time, contributing to the optimization of functional

Hanaro operation

International Nuclear Information System (INIS)

Lee, Ji Bok; Jeon, Byung Jin; Kwack, Byung Ho

1997-01-01

HANARO was configurated its first operating core in 1995. Long term operation test was conducted up to 3-1 cycle during 1996, in order to investigate the reactor characteristics due to fuel depletion and additional fuel loading. Now HANARO has accumulated 168.4 days of total operation time and 2,687.5 MWD of total thermal output. Reactor analysis, producing operation datum and its validation with test, periodic inspection and maintenance of the facility are continuously conducted for safe operation of the HANARO. Conducted the verification tests for installed utilization facilities, and successfully performed the radiation emergency drill. The shutdown report of TRIGA Mark II and III was submitted to MOST, and decommissioning will be started from 1997. (author). 70 tabs., 50 figs., 27 refs

Periodic solution for state-dependent impulsive shunting inhibitory CNNs with time-varying delays.

Science.gov (United States)

Şaylı, Mustafa; Yılmaz, Enes

2015-08-01

In this paper, we consider existence and global exponential stability of periodic solution for state-dependent impulsive shunting inhibitory cellular neural networks with time-varying delays. By means of B-equivalence method, we reduce these state-dependent impulsive neural networks system to an equivalent fix time impulsive neural networks system. Further, by using Mawhin's continuation theorem of coincide degree theory and employing a suitable Lyapunov function some new sufficient conditions for existence and global exponential stability of periodic solution are obtained. Previous results are improved and extended. Finally, we give an illustrative example with numerical simulations to demonstrate the effectiveness of our theoretical results. Copyright © 2015 Elsevier Ltd. All rights reserved.

Differences in night-time and daytime ambulatory blood pressure when diurnal periods are defined by self-report, fixed-times, and actigraphy: Improving the Detection of Hypertension study.

Science.gov (United States)

Booth, John N; Muntner, Paul; Abdalla, Marwah; Diaz, Keith M; Viera, Anthony J; Reynolds, Kristi; Schwartz, Joseph E; Shimbo, Daichi

2016-02-01

To determine whether defining diurnal periods by self-report, fixed-time, or actigraphy produce different estimates of night-time and daytime ambulatory blood pressure (ABP). Over a median of 28 days, 330 participants completed two 24-h ABP and actigraphy monitoring periods with sleep diaries. Fixed night-time and daytime periods were defined as 0000-0600 h and 1000-2000 h, respectively. Using the first ABP period, within-individual differences for mean night-time and daytime ABP and kappa statistics for night-time and daytime hypertension (systolic/diastolic ABP≥120/70 mmHg and ≥135/85 mmHg, respectively) were estimated comparing self-report, fixed-time, or actigraphy for defining diurnal periods. Reproducibility of ABP was also estimated. Within-individual mean differences in night-time systolic ABP were small, suggesting little bias, when comparing the three approaches used to define diurnal periods. The distribution of differences, represented by 95% confidence intervals (CI), in night-time systolic and diastolic ABP and daytime systolic and diastolic ABP was narrowest for self-report versus actigraphy. For example, mean differences (95% CI) in night-time systolic ABP for self-report versus fixed-time was -0.53 (-6.61, +5.56) mmHg, self-report versus actigraphy was 0.91 (-3.61, +5.43) mmHg, and fixed-time versus actigraphy was 1.43 (-5.59, +8.46) mmHg. Agreement for night-time and daytime hypertension was highest for self-report versus actigraphy: kappa statistic (95% CI) = 0.91 (0.86,0.96) and 1.00 (0.98,1.00), respectively. The reproducibility of mean ABP and hypertension categories was similar using each approach. Given the high agreement with actigraphy, these data support using self-report to define diurnal periods on ABP monitoring. Further, the use of fixed-time periods may be a reasonable alternative approach.

Wuchereria bancrofti in Tanzania: microfilarial periodicity and effect of blood sampling time on microfilarial intensities

DEFF Research Database (Denmark)

Simonsen, Poul Erik; Niemann, L.; Meyrowitsch, Dan Wolf

1997-01-01

The circadian periodicity of Wuchereria bancrofti microfilarial (mf) intensities in peripheral blood was analysed in a group of infected individuals from an endemic community in north-eastern Tanzania. The mf density was quantified at two-hourly intervals for 24 hours. A clear nocturnal periodic...... of blood sampling before peak time is discussed, and the importance of taking sampling time into consideration when analysing data from epidemiological studies is emphasized. A simple method is devised which can be used to adjust for the influence of time on mf intensities, in studies where accurate...... information on mf intensities is necessary, and where it is impossible to obtain all samples at peak time....

Nonunitary similarity transformation of conservative to dissipative evolutions: Intertwining without time operator

Science.gov (United States)

Gómez, Fernando

2007-04-01

Reversible evolutions are usually expressed in terms of unitary groups on separable Hilbert spaces, whereas irreversible ones are described by contraction semigroups. In the theory of nonunitary similarity transformations intertwining unitary groups and contraction semigroups, proposed initially in the context of statistical mechanics as part of an exact theory of irreversibility, the unitary groups with such intertwining property have been qualified by the existence of an internal time operator. This work tackles the question of existence of internal time operators for unitary groups with the intertwining property. Equivalent conditions to the existence of internal time operators for such unitary groups are given on the basis of the Sz.-Nagy-Foiaş [Harmonic Analysis of Operators on Hilbert Spaces (North-Holland, Amsterdam, 1970)] dilation theory and the theory of shift invariant subspaces. These conditions permit us to solve the inverse intertwining problem in the negative: there are unitary groups with the intertwining property which do not admit internal time operator. A representative family of such unitary groups is given.

Practitioners' Perceptions of the Soccer Extra-Time Period: Implications for Future Research.

Directory of Open Access Journals (Sweden)

Liam D Harper

Full Text Available Qualitative research investigating soccer practitioners' perceptions can allow researchers to create practical research investigations. The extra-time period of soccer is understudied compared to other areas of soccer research. Using an open-ended online survey containing eleven main and nine sub questions, we gathered the perceptions of extra-time from 46 soccer practitioners, all working for different professional soccer clubs. Questions related to current practices, views on extra-time regulations, and ideas for future research. Using inductive content analysis, the following general dimensions were identified: 'importance of extra-time', 'rule changes', 'efficacy of extra-time hydro-nutritional provision', 'nutritional timing', 'future research directions', 'preparatory modulations' and 'recovery'. The majority of practitioners (63% either agreed or strongly agreed that extra-time is an important period for determining success in knockout football match-play. When asked if a fourth substitution should be permitted in extra-time, 67% agreed. The use of hydro-nutritional strategies prior to extra-time was predominately considered important or very important. However; only 41% of practitioners felt that it was the most important time point for the use of nutritional products. A similar number of practitioners account (50% and do not (50% account for the potential of extra-time when training and preparing players and 89% of practitioners stated that extra-time influences recovery practices following matches. In the five minute break prior to extra-time, the following practices (in order of priority were advocated to players: hydration, energy provision, massage, and tactical preparations. Additionally, 87% of practitioners advocate a particular nutritional supplementation strategy prior to extra-time. In order of importance, practitioners see the following as future research areas: nutritional interventions, fatigue responses, acute injury risk

Practitioners' Perceptions of the Soccer Extra-Time Period: Implications for Future Research.

Science.gov (United States)

Harper, Liam D; Fothergill, Melissa; West, Daniel J; Stevenson, Emma; Russell, Mark

2016-01-01

Qualitative research investigating soccer practitioners' perceptions can allow researchers to create practical research investigations. The extra-time period of soccer is understudied compared to other areas of soccer research. Using an open-ended online survey containing eleven main and nine sub questions, we gathered the perceptions of extra-time from 46 soccer practitioners, all working for different professional soccer clubs. Questions related to current practices, views on extra-time regulations, and ideas for future research. Using inductive content analysis, the following general dimensions were identified: 'importance of extra-time', 'rule changes', 'efficacy of extra-time hydro-nutritional provision', 'nutritional timing', 'future research directions', 'preparatory modulations' and 'recovery'. The majority of practitioners (63%) either agreed or strongly agreed that extra-time is an important period for determining success in knockout football match-play. When asked if a fourth substitution should be permitted in extra-time, 67% agreed. The use of hydro-nutritional strategies prior to extra-time was predominately considered important or very important. However; only 41% of practitioners felt that it was the most important time point for the use of nutritional products. A similar number of practitioners account (50%) and do not (50%) account for the potential of extra-time when training and preparing players and 89% of practitioners stated that extra-time influences recovery practices following matches. In the five minute break prior to extra-time, the following practices (in order of priority) were advocated to players: hydration, energy provision, massage, and tactical preparations. Additionally, 87% of practitioners advocate a particular nutritional supplementation strategy prior to extra-time. In order of importance, practitioners see the following as future research areas: nutritional interventions, fatigue responses, acute injury risk, recovery

Technology strategy for integrated operations and real time reservoir management; Technology Target Areas; TTA5 - Integrated operations and RTRM

Energy Technology Data Exchange (ETDEWEB)

2007-07-01

In Norway Integrated Operations (IO) is a concept which in the first phase (G1) has been used to describe how to integrate processes and people onshore and offshore using ICT solutions and facilities that improve onshore's ability to support offshore operationally. The second generation (G2) Integrated Operations aims to help operators utilize vendors' core competencies and services more efficiently. Utilizing digital services and vendor products, operators will be able to update reservoir models, drilling targets and well trajectories as wells are drilled, manage well completions remotely, optimize production from reservoir to export lines, and implement condition-based maintenance concepts. The total impact on production, recovery rates, costs and safety will be profound. When the international petroleum business moves to the Arctic region the setting is very different from what is the case on the Norwegian Continental Shelf (NCS) and new challenges will arise. The Norwegian Ministry of Environment has recently issued an Integrated Management Plan for the Barents Sea where one focus is on 'Monitoring of the Marine Environment in the North'. The Government aims to establish a new and more coordinated system for monitoring the marine ecosystems in the north. A representative group consisting of the major Operators, the Service Industry, Academia and the Authorities have developed the enclosed strategy for the OG21 Integrated Operations and Real Time Reservoir Management (IO and RTRM) Technology Target Area (TTA). Major technology and work process research and development gaps have been identified in several areas: Bandwidth down-hole to surface; Sensor development including Nano-technology; Cross discipline use of Visualisation, Simulation and model development particularly in Drilling and Reservoir management areas; Software development in terms of data handling, model updating and calculation speed; Enabling reliable and robust communications particularly for

Technology strategy for integrated operations and real time reservoir management; Technology Target Areas; TTA5 - Integrated operations and RTRM

Energy Technology Data Exchange (ETDEWEB)

2007-07-01

In Norway Integrated Operations (IO) is a concept which in the first phase (G1) has been used to describe how to integrate processes and people onshore and offshore using ICT solutions and facilities that improve onshore's ability to support offshore operationally. The second generation (G2) Integrated Operations aims to help operators utilize vendors' core competencies and services more efficiently. Utilizing digital services and vendor products, operators will be able to update reservoir models, drilling targets and well trajectories as wells are drilled, manage well completions remotely, optimize production from reservoir to export lines, and implement condition-based maintenance concepts. The total impact on production, recovery rates, costs and safety will be profound. When the international petroleum business moves to the Arctic region the setting is very different from what is the case on the Norwegian Continental Shelf (NCS) and new challenges will arise. The Norwegian Ministry of Environment has recently issued an Integrated Management Plan for the Barents Sea where one focus is on 'Monitoring of the Marine Environment in the North'. The Government aims to establish a new and more coordinated system for monitoring the marine ecosystems in the north. A representative group consisting of the major Operators, the Service Industry, Academia and the Authorities have developed the enclosed strategy for the OG21 Integrated Operations and Real Time Reservoir Management (IO and RTRM) Technology Target Area (TTA). Major technology and work process research and development gaps have been identified in several areas: Bandwidth down-hole to surface; Sensor development including Nano-technology; Cross discipline use of Visualisation, Simulation and model development particularly in Drilling and Reservoir management areas; Software development in terms of data handling, model updating and calculation speed; Enabling reliable and robust communications

Clinical efficacy ofω-3 polyunsaturated fatty acids in perioperative period of radical operation for gastric cancer

Directory of Open Access Journals (Sweden)

Wei-Xue Li

2018-01-01

Full Text Available Objective: To study the regulating effect of application of ω-3 polyunsaturated fatty acids in perioperative period of radical surgery for gastric cancer on patients’ nutritional status, inflammatory response and immune function. Methods: A total of 86 cases of patients receiving radical operation for gastric cancer in our hospital were selected for study and randomly divided into two groups, ω-3 PUFAs group received ω-3 polyunsaturated fatty acids combined with conventional intravenous nutritional support and control group only received conventional intravenous nutritional support. Serum nutrition indicators of two groups were detected before and after surgery, and inflammation indicators in serum as well as immune molecules in tumor tissue of tow groups were detected after surgery. Results: 1d before operation and 3 d after operation, serum RBP, PA, RTF, PEPT1 and ghrelin contents of ω-3 PUFAs group were significantly higher than those of control group; 3 d after operation, serum CC16, α-MSH and HSP70 contents of ω-3 PUFAs group were significantly higher than those of control group, and LBP and sCD14 contents were significantly lower than those of control group; B7-H1, B7-H4, CD157 and CD133 contents in tumor tissue of ω-3 PUFAs group were significantly lower than those of control group, and CD11c content was significantly higher than that of control group. Conclusion: Application of ω-3 polyunsaturated fatty acids in perioperative period of radical operation for gastric cancer can improve patients’ nutritional status, reduce postoperative inflammatory response caused by surgical trauma and regulate the expression of immune molecules in tumor tissue.

Extended operating times are more efficient, save money and maintain a high staff and patient satisfaction.

Science.gov (United States)

Herron, Jonathan Blair Thomas; French, Rachel; Gilliam, Andrew Douglas

2018-01-01

Current public sector austerity measures necessitate efficiency savings throughout the NHS. Performance targets have resulted in activity being performed in the private sector, waiting list initiative lists and requests for staff to work overtime. This has resulted in staff fatigue and additional agency costs. Adoption of extended operating theatre times (0800-1800 hours) may improve productivity and efficiency, with potentially significant financial savings; however, implementation may adversely affect staff morale and patient compliance. A pilot period of four months of extended operating times (4.5 hour sessions) was completed and included all theatre surgical specialties. Outcome measures included: the number of cases completed, late starts, early finishes, cancelled operations, theatre overruns, preoperative assessment and 18-week targets. The outcomes were then compared to pre-existing normal working day operating lists (0900-1700). Theatre staff, patient and surgical trainee satisfaction with the system were also considered by use of an anonymous questionnaire. The study showed that in-session utilisation time was unchanged by extended operating hours 88.7% (vs 89.2%). The service was rated as 'good' or 'excellent' by 87.5% of patients. Over £345,000 was saved by reducing premium payments. Savings of £225,000 were made by reducing privately outsourced operation and a further £63,000 by reviewing staff hours. Day case procedures increased from 2.8 to 3.2 cases/day with extended operating. There was no significant increase in late starts (5.1% vs 6.8%) or cancellation rates (0.75% vs 1.02%). Theatre over-runs reduced from 5% to 3.4%. The 18 weeks target for surgery was achieved in 93.7% of cases (vs 88.3%). The number of elective procedures increased from 4.1 to 4.89 cases/day. Only 13.33% of trainees (n = 33) surveyed felt that extended operating had a negative impact on training. The study concludes that extended operating increased productivity from

Optimization of enhanced biological phosphorus removal after periods of low loading.

Science.gov (United States)

Miyake, Haruo; Morgenroth, Eberhard

2005-01-01

Enhanced biological phosphorus removal is a well-established technology for the treatment of municipal wastewater. However, increased effluent phosphorus concentrations have been reported after periods (days) of low organic loading. The purpose of this study was to evaluate different operating strategies to prevent discharge of effluent after such low-loading periods. Mechanisms leading to these operational problems have been related to the reduction of polyphosphate-accumulating organisms (PAOs) and their storage compounds (polyhydroxy alkanoates [PHA]). Increased effluent phosphorus concentrations can be the result of an imbalance between influent loading and PAOs in the system and an imbalance between phosphorus release and uptake rates. The following operating conditions were tested in their ability to prevent a reduction of PHA and of overall biomass during low organic loading conditions: (a) unchanged operation, (b) reduced aeration time, (c) reduced sludge wastage, and (d) combination of reduced aeration time and reduced sludge wastage. Experiments were performed in a laboratory-scale anaerobic-aerobic sequencing batch reactor, using acetate as the carbon source. Without operational adjustments, phosphorus-release rates decreased during low-loading periods but recovered rapidly. Phosphorus-uptake rates also decreased, and the recovery typically required several days to increase to normal levels. The combination of reduced aeration time and reduced sludge wastage allowed the maintenance of constant levels of both PHA and overall biomass. A mathematical model was used to explain the influence of the tested operating conditions on PAO and PHA concentrations. While experimental results were in general agreement with model predictions, the kinetic expression for phosphorus uptake deviated significantly for the first 24 hours after low-loading conditions. Mechanisms leading to these deviations need to be further investigated.

Real-time solar magnetograph operation system software design and user's guide

Science.gov (United States)

Wang, C.

1984-01-01

The Real Time Solar Magnetograph (RTSM) Operation system software design on PDP11/23+ is presented along with the User's Guide. The RTSM operation software is for real time instrumentation control, data collection and data management. The data is used for vector analysis, plotting or graphics display. The processed data is then easily compared with solar data from other sources, such as the Solar Maximum Mission (SMM).

40 CFR 62.14645 - What happens during periods of startup, shutdown, and malfunction?

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false What happens during periods of startup... Limits § 62.14645 What happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during periods of CISWI unit startup, shutdown, or...

Delay-Dependent Stability Criteria of Uncertain Periodic Switched Recurrent Neural Networks with Time-Varying Delays

Directory of Open Access Journals (Sweden)

Xing Yin

2011-01-01

uncertain periodic switched recurrent neural networks with time-varying delays. When uncertain discrete-time recurrent neural network is a periodic system, it is expressed as switched neural network for the finite switching state. Based on the switched quadratic Lyapunov functional approach (SQLF and free-weighting matrix approach (FWM, some linear matrix inequality criteria are found to guarantee the delay-dependent asymptotical stability of these systems. Two examples illustrate the exactness of the proposed criteria.

Computing return times or return periods with rare event algorithms

Science.gov (United States)

Lestang, Thibault; Ragone, Francesco; Bréhier, Charles-Edouard; Herbert, Corentin; Bouchet, Freddy

2018-04-01

The average time between two occurrences of the same event, referred to as its return time (or return period), is a useful statistical concept for practical applications. For instance insurances or public agencies may be interested by the return time of a 10 m flood of the Seine river in Paris. However, due to their scarcity, reliably estimating return times for rare events is very difficult using either observational data or direct numerical simulations. For rare events, an estimator for return times can be built from the extrema of the observable on trajectory blocks. Here, we show that this estimator can be improved to remain accurate for return times of the order of the block size. More importantly, we show that this approach can be generalised to estimate return times from numerical algorithms specifically designed to sample rare events. So far those algorithms often compute probabilities, rather than return times. The approach we propose provides a computationally extremely efficient way to estimate numerically the return times of rare events for a dynamical system, gaining several orders of magnitude of computational costs. We illustrate the method on two kinds of observables, instantaneous and time-averaged, using two different rare event algorithms, for a simple stochastic process, the Ornstein–Uhlenbeck process. As an example of realistic applications to complex systems, we finally discuss extreme values of the drag on an object in a turbulent flow.

Investigation of the effects of time periodic pressure and engpotential gradients on viscoelastic fluid flow in circular narrow confinements

DEFF Research Database (Denmark)

Nguyen, Trieu; van der Meer, Devaraj; van den Berg, Albert

2017-01-01

-Boltzmann equation, together with the incompressible Cauchy momentum equation under no-slip boundary conditions for viscoelastic fluid in the case of a combination of time periodic pressure-driven and electro-osmotic flow. The resulting solutions allow us to predict the electrical current and solution flow rate...... conversion applications. We also found that time periodic electro-osmotic flow in many cases is much stronger enhanced than time periodic pressure-driven flow when comparing the flow profiles of oscillating PDF and EOF in micro-and nanochannels. The findings advance our understanding of time periodic......In this paper we present an in-depth analysis and analytical solution for time periodic hydrodynamic flow (driven by a time-dependent pressure gradient and electric field) of viscoelastic fluid through cylindrical micro-and nanochannels. Particularly, we solve the linearized Poisson...

Rank One Strange Attractors in Periodically Kicked Predator-Prey System with Time-Delay

Science.gov (United States)

Yang, Wenjie; Lin, Yiping; Dai, Yunxian; Zhao, Huitao

2016-06-01

This paper is devoted to the study of the problem of rank one strange attractor in a periodically kicked predator-prey system with time-delay. Our discussion is based on the theory of rank one maps formulated by Wang and Young. Firstly, we develop the rank one chaotic theory to delayed systems. It is shown that strange attractors occur when the delayed system undergoes a Hopf bifurcation and encounters an external periodic force. Then we use the theory to the periodically kicked predator-prey system with delay, deriving the conditions for Hopf bifurcation and rank one chaos along with the results of numerical simulations.

Preliminary Investigation of Time Remaining Display on the Computer-based Emergency Operating Procedure

Science.gov (United States)

Suryono, T. J.; Gofuku, A.

2018-02-01

One of the important thing in the mitigation of accidents in nuclear power plant accidents is time management. The accidents should be resolved as soon as possible in order to prevent the core melting and the release of radioactive material to the environment. In this case, operators should follow the emergency operating procedure related with the accident, in step by step order and in allowable time. Nowadays, the advanced main control rooms are equipped with computer-based procedures (CBPs) which is make it easier for operators to do their tasks of monitoring and controlling the reactor. However, most of the CBPs do not include the time remaining display feature which informs operators of time available for them to execute procedure steps and warns them if the they reach the time limit. Furthermore, the feature will increase the awareness of operators about their current situation in the procedure. This paper investigates this issue. The simplified of emergency operating procedure (EOP) of steam generator tube rupture (SGTR) accident of PWR plant is applied. In addition, the sequence of actions on each step of the procedure is modelled using multilevel flow modelling (MFM) and influenced propagation rule. The prediction of action time on each step is acquired based on similar case accidents and the Support Vector Regression. The derived time will be processed and then displayed on a CBP user interface.

Effect of different anesthesia methods on plasma neuropeptides levels during the peri-operative period in surgical patients with hypertension

International Nuclear Information System (INIS)

Li Hong; He Haomin; Tian Xiaoping

2003-01-01

Objective: To explore the effect of different anesthesia methods on the levels of plasma neuropeptides during the peri-operative period in patients with hypertension. Methods: Ninety hypertensive patients undergoing upper abdominal operations were randomly allocated to equal divided epidural anesthesia, general anesthesia and combined Groups. Plasma neuropeptide Y(NPY) concentrations were measured before anesthesia, at 15 min after anesthesia, 20 min after operation and 10 min after completion of the operation. Results: BP, HR and NPY were significantly changed in both E group and G group after anesthesia and operation (compared vs before anesthesia, p<0.01). BP, HR and NPY were significantly changed in C group after operation compared with those in both E and G group (p<0.05) . Conclusion: The combined anesthesia method is effective in inhibits the stress response during upper abdominal operation in the hypertensive patients

Generalized Bilinear Differential Operators, Binary Bell Polynomials, and Exact Periodic Wave Solution of Boiti-Leon-Manna-Pempinelli Equation

Directory of Open Access Journals (Sweden)

Huanhe Dong

2014-01-01

Full Text Available We introduce how to obtain the bilinear form and the exact periodic wave solutions of a class of (2+1-dimensional nonlinear integrable differential equations directly and quickly with the help of the generalized Dp-operators, binary Bell polynomials, and a general Riemann theta function in terms of the Hirota method. As applications, we solve the periodic wave solution of BLMP equation and it can be reduced to soliton solution via asymptotic analysis when the value of p is 5.

Discrete time analysis of a repairable machine

OpenAIRE

Alfa, Attahiru Sule; Castro, I. T.

2002-01-01

We consider, in discrete time, a single machine system that operates for a period of time represented by a general distribution. This machine is subject to failures during operations and the occurrence of these failures depends on how many times the machine has previously failed. Some failures are repairable and the repair times may or may not depend on the number of times the machine was previously repaired. Repair times also have a general distribution. The operating times...

Stability of horizontal viscous fluid layers in a vertical arbitrary time periodic electric field

Science.gov (United States)

Bandopadhyay, Aditya; Hardt, Steffen

2017-12-01

The stability of a horizontal interface between two viscous fluids, one of which is conducting and the other is dielectric, acted upon by a vertical time-periodic electric field is considered theoretically. The two fluids are bounded by electrodes separated by a finite distance. For an applied ac electric field, the unstable interface deforms in a time periodic manner, owing to the time dependent Maxwell stress, and is characterized by the oscillation frequency which may or may not be the same as the frequency of the ac electric field. The stability curve, which relates the critical voltage, manifested through the Mason number—the ratio of normal electric stress and viscous stress, and the instability wavenumber at the onset of the instability, is obtained by means of the Floquet theory for a general arbitrary time periodic electric field. The limit of vanishing viscosities is shown to be in excellent agreement with the marginal stability curves predicted by means of a Mathieu equation. The influence of finite viscosity and electrode separation is discussed in relation to the ideal case of inviscid fluids. The methodology to obtain the marginal stability curves developed here is applicable to any arbitrary but time periodic signal, as demonstrated for the case of a signal with two different frequencies, and four different frequencies with a dc offset. The mode coupling in the interfacial normal stress leads to appearance of harmonic and subharmonic modes, characterized by the frequency of the oscillating interface at an integral or half-integral multiple of the applied frequency, respectively. This is in contrast to the application of a voltage with a single frequency which always leads to a harmonic mode oscillation of the interface. Whether a harmonic or subharmonic mode is the most unstable one depends on details of the excitation signal.

Time-of-flight spectrometers

International Nuclear Information System (INIS)

Carrico, J.P.

1976-01-01

The flight time of an ion in an inhomogeneous, oscillatory electric field (IOFE) is an m/e-dependent property of this field and is independent of the initial position and velocity. The d.c. component of the equation of motion for an ion in the IOFE describes a harmonic oscillation of constant period. When ions oscillate for many periods with one species overtaking another the motion may no longer be truly periodic although the resulting period or 'quasi-period' still remains independent of the initial conditions. This period or 'quasi-period' is used in the time-of-flight mass spectrometer described. The principle of operation is also described and both analytical and experimental results are reported. (B.D.)

Time series modelling of increased soil temperature anomalies during long period

Science.gov (United States)

Shirvani, Amin; Moradi, Farzad; Moosavi, Ali Akbar

2015-10-01

Soil temperature just beneath the soil surface is highly dynamic and has a direct impact on plant seed germination and is probably the most distinct and recognisable factor governing emergence. Autoregressive integrated moving average as a stochastic model was developed to predict the weekly soil temperature anomalies at 10 cm depth, one of the most important soil parameters. The weekly soil temperature anomalies for the periods of January1986-December 2011 and January 2012-December 2013 were taken into consideration to construct and test autoregressive integrated moving average models. The proposed model autoregressive integrated moving average (2,1,1) had a minimum value of Akaike information criterion and its estimated coefficients were different from zero at 5% significance level. The prediction of the weekly soil temperature anomalies during the test period using this proposed model indicated a high correlation coefficient between the observed and predicted data - that was 0.99 for lead time 1 week. Linear trend analysis indicated that the soil temperature anomalies warmed up significantly by 1.8°C during the period of 1986-2011.

Predictors of shoulder dystocia at the time of operative vaginal delivery.

Science.gov (United States)

Palatnik, Anna; Grobman, William A; Hellendag, Madeline G; Janetos, Timothy M; Gossett, Dana R; Miller, Emily S

2016-11-01

It remains uncertain whether clinical factors known prior to delivery can predict which women are more likely to experience shoulder dystocia in the setting of operative vaginal delivery. We sought to identify whether shoulder dystocia can be accurately predicted among women undergoing an operative vaginal delivery. This was a case-control study of women undergoing a low or outlet operative vaginal delivery from 2005 through 2014 in a single tertiary care center. Cases were defined as women who experienced a shoulder dystocia at the time of operative vaginal delivery. Controls consisted of women without a shoulder dystocia at the time of operative vaginal delivery. Variables previously identified to be associated with shoulder dystocia that could be known prior to delivery were abstracted from the medical records. Bivariable analyses and multivariable logistic regression were used to identify factors independently associated with shoulder dystocia. A receiver operating characteristic curve was created to evaluate the predictive value of the model for shoulder dystocia. Of the 4080 women who met inclusion criteria, shoulder dystocia occurred in 162 (4.0%) women. In bivariable analysis, maternal age, parity, body mass index, diabetes, chorioamnionitis, arrest disorder as an indication for an operative vaginal delivery, vacuum use, and estimated fetal weight >4 kg were significantly associated with shoulder dystocia. In multivariable analysis, parity, diabetes, chorioamnionitis, arrest disorder as an indication for operative vaginal delivery, vacuum use, and estimated fetal weight >4 kg remained independently associated with shoulder dystocia. The area under the curve for the generated receiver operating characteristic curve was 0.73 (95% confidence interval, 0.69-0.77), demonstrating only a modest ability to predict shoulder dystocia before performing an operative vaginal delivery. While risk factors for shoulder dystocia at the time of operative vaginal delivery

Real time operating system for a nuclear power plant computer

International Nuclear Information System (INIS)

Alger, L.S.; Lala, J.H.

1986-01-01

A quadruply redundant synchronous fault tolerant processor (FTP) is now under fabrication at the C.S. Draper Laboratory to be used initially as a trip monitor for the Experimental Breeder Reactor EBR-II operated by the Argonne National Laboratory in Idaho Falls, Idaho. The real time operating system for this processor is described

A HARDWARE SUPPORTED OPERATING SYSTEM KERNEL FOR EMBEDDED HARD REAL-TIME APPLICATIONS

NARCIS (Netherlands)

COLNARIC, M; HALANG, WA; TOL, RM

1994-01-01

The concept of the kernel, i.e. the time critical part of a real-time operating system, and its dedicated co-processor, especially tailored for embedded applications, are presented. The co-processor acts as a system controller and operates in conjunction with one or more conventional processors in

Response Times of Operators in a Control Room

DEFF Research Database (Denmark)

Platz, O.; Rasmussen, Jens; Skanborg, Preben Zacho

A statistical analysis was made of operator response times recorded in the control room of a research reactor during the years 1972-1974. A homogeneity test revealed that the data consist of a mixture of populations. A small but statistically significant difference is found between day and night...

Real-Time Integrated Re-scheduling for Tramway Operations

NARCIS (Netherlands)

Cheung, Kam-Fung; Kuo, Yong-Hong; Lai, S.W.; Leung, Janny M.Y.

2018-01-01

Our work aims to develop practical solution approaches for real-time dispatch of crews and vehicles for disruption management. The practical motivation for our research arose from the operations of a public tramway system in Hong Kong. The tram system shares the road with other vehicular traffic in

Automatic pipeline operation using Petri Nets

Energy Technology Data Exchange (ETDEWEB)

Moreira, Guilherme O. [PETROBRAS TRANSPORTE S.A., Rio de Janeiro, RJ (Brazil)

2009-07-01

A pipeline operation requires several actions, attention and time from the control room operator in each of its operating phases. This article proposition is to use automation as something more than a remote control, drastically reducing the number of repetitive and routine actions needed from the operator to start and stop the system, granting more time for system supervision, decision making during critical conditions and avoiding errors caused due to the need of several actions being executed in a short period of time. To achieve these objectives the pipeline operation will be modeled as a Petri Net consisting of states, event and actions. A methodology for converting this Petri Net into a Ladder controller code will also be proposed. (author)

Mixed - mode Operating System for Real - time Performance

Directory of Open Access Journals (Sweden)

Hasan M. M.

2017-11-01

Full Text Available The purpose of the mixed-mode system research is to handle devices with the accuracy of real-time systems and at the same time, having all the benefits and facilities of a matured Graphic User Interface(GUIoperating system which is typicallynon-real-time. This mixed-mode operating system comprising of a real-time portion and a non-real-time portion was studied and implemented to identify the feasibilities and performances in practical applications (in the context of scheduled the real-time events. In this research an i8751 microcontroller-based hardware was used to measure the performance of the system in real-time-only as well as non-real-time-only configurations. The real-time portion is an 486DX-40 IBM PC system running under DOS-based real-time kernel and the non-real-time portion is a Pentium IIIbased system running under Windows NT. It was found that mixed-mode systems performed as good as a typical real-time system and in fact, gave many additional benefits such as simplified/modular programming and load tolerance.

TWOS - TIME WARP OPERATING SYSTEM, VERSION 2.5.1

Science.gov (United States)

Bellenot, S. F.

1994-01-01

The Time Warp Operating System (TWOS) is a special-purpose operating system designed to support parallel discrete-event simulation. TWOS is a complete implementation of the Time Warp mechanism, a distributed protocol for virtual time synchronization based on process rollback and message annihilation. Version 2.5.1 supports simulations and other computations using both virtual time and dynamic load balancing; it does not support general time-sharing or multi-process jobs using conventional message synchronization and communication. The program utilizes the underlying operating system's resources. TWOS runs a single simulation at a time, executing it concurrently on as many processors of a distributed system as are allocated. The simulation needs only to be decomposed into objects (logical processes) that interact through time-stamped messages. TWOS provides transparent synchronization. The user does not have to add any more special logic to aid in synchronization, nor give any synchronization advice, nor even understand much about how the Time Warp mechanism works. The Time Warp Simulator (TWSIM) subdirectory contains a sequential simulation engine that is interface compatible with TWOS. This means that an application designer and programmer who wish to use TWOS can prototype code on TWSIM on a single processor and/or workstation before having to deal with the complexity of working on a distributed system. TWSIM also provides statistics about the application which may be helpful for determining the correctness of an application and for achieving good performance on TWOS. Version 2.5.1 has an updated interface that is not compatible with 2.0. The program's user manual assists the simulation programmer in the design, coding, and implementation of discrete-event simulations running on TWOS. The manual also includes a practical user's guide to the TWOS application benchmark, Colliding Pucks. TWOS supports simulations written in the C programming language. It is designed

Applicable value of real time interventional ultrasound guidance in family planning reproduction operation

International Nuclear Information System (INIS)

Wu Guoping; Zou Dongfang; Sun Jian; Dong Weihua

2007-01-01

Objective: To determine the clinical value of real time interventional ultrasound guidance in family planning reproduction operation. Methods: Under the guidance of ultrasound monitoring, 522 cases with high risk and difficult uterine operation were undertaken in our department. Results: The abdominal endoscopic contraceptive uterine operation under real time ultrasound monitoring was carried out for 522 cases in 4 years, with successful rates for high risk pregnancy as 287/289 cases, high risk troublesome withdrawal of contraceptive ring as 129/130 cases and puzzling uterine operation as 103/103 cases. The total successful rate reached 99.42%, without uterine rupture and other complications. Conclusion: The former complex, blind and difficult uterine operations turn to be simple, safe and reliable under the guidance of real time ultrasound. (authors)

Tunneling time through a barrier using the tempus operator

Energy Technology Data Exchange (ETDEWEB)

Kobe, Donald H.; Aguilera-Navarro, Valdir C. [North Texas Univ., Denton, TX (United States). Dept. of Physics

1996-11-01

The time a particle spends in a classically forbidden region of a potential barrier is expressed as an expectation value of the time operator in that region. Classically, time is canonically conjugate to the energy and is equal to the time a conservative system. The tunneling time is calculated by this approach for a rectangular barrier, which gives a complex time. The imaginary part of the time is non negative, so it is interpreted as a tunneling time. The real part gives a negative value for some values of the parameters, and is therefore rejected because it violates causality. This tunneling time is compared with other tunneling times that have been suggested by also calculating them for the rectangular barrier. 58 refs., 7 figs.

Tunneling time through a barrier using the tempus operator

International Nuclear Information System (INIS)

Kobe, Donald H.; Aguilera-Navarro, Valdir C.

1996-11-01

The time a particle spends in a classically forbidden region of a potential barrier is expressed as an expectation value of the time operator in that region. Classically, time is canonically conjugate to the energy and is equal to the time a conservative system. The tunneling time is calculated by this approach for a rectangular barrier, which gives a complex time. The imaginary part of the time is non negative, so it is interpreted as a tunneling time. The real part gives a negative value for some values of the parameters, and is therefore rejected because it violates causality. This tunneling time is compared with other tunneling times that have been suggested by also calculating them for the rectangular barrier. 58 refs., 7 figs

Time-varying singular value decomposition for periodic transient identification in bearing fault diagnosis

Science.gov (United States)

Zhang, Shangbin; Lu, Siliang; He, Qingbo; Kong, Fanrang

2016-09-01

For rotating machines, the defective faults of bearings generally are represented as periodic transient impulses in acquired signals. The extraction of transient features from signals has been a key issue for fault diagnosis. However, the background noise reduces identification performance of periodic faults in practice. This paper proposes a time-varying singular value decomposition (TSVD) method to enhance the identification of periodic faults. The proposed method is inspired by the sliding window method. By applying singular value decomposition (SVD) to the signal under a sliding window, we can obtain a time-varying singular value matrix (TSVM). Each column in the TSVM is occupied by the singular values of the corresponding sliding window, and each row represents the intrinsic structure of the raw signal, namely time-singular-value-sequence (TSVS). Theoretical and experimental analyses show that the frequency of TSVS is exactly twice that of the corresponding intrinsic structure. Moreover, the signal-to-noise ratio (SNR) of TSVS is improved significantly in comparison with the raw signal. The proposed method takes advantages of the TSVS in noise suppression and feature extraction to enhance fault frequency for diagnosis. The effectiveness of the TSVD is verified by means of simulation studies and applications to diagnosis of bearing faults. Results indicate that the proposed method is superior to traditional methods for bearing fault diagnosis.

Use of an operating microscope during spine surgery is associated with minor increases in operating room times and no increased risk of infection.

Science.gov (United States)

Basques, Bryce A; Golinvaux, Nicholas S; Bohl, Daniel D; Yacob, Alem; Toy, Jason O; Varthi, Arya G; Grauer, Jonathan N

2014-10-15

Retrospective database review. To evaluate whether microscope use during spine procedures is associated with increased operating room times or increased risk of infection. Operating microscopes are commonly used in spine procedures. It is debated whether the use of an operating microscope increases operating room time or confers increased risk of infection. The American College of Surgeons National Surgical Quality Improvement Program database, which includes data from more than 370 participating hospitals, was used to identify patients undergoing elective spinal procedures with and without the use of an operating microscope for the years 2011 and 2012. Bivariate and multivariate linear regressions were used to test the association between microscope use and operating room times. Bivariate and multivariate logistic regressions were similarly conducted to test the association between microscope use and infection occurrence within 30 days of surgery. A total of 23,670 elective spine procedures were identified, of which 2226 (9.4%) used an operating microscope. The average patient age was 55.1±14.4 years. The average operative time (incision to closure) was 125.7±82.0 minutes.Microscope use was associated with minor increases in preoperative room time (+2.9 min, P=0.013), operative time (+13.2 min, Pmicroscope and nonmicroscope groups for occurrence of any infection, superficial surgical site infection, deep surgical site infection, organ space infection, or sepsis/septic shock, regardless of surgery type. We did not find operating room times or infection risk to be significant deterrents for use of an operating microscope during spine surgery. 3.

A new continuous-time formulation for scheduling crude oil operations

International Nuclear Information System (INIS)

Reddy, P. Chandra Prakash; Karimi, I.A.; Srinivasan, R.

2004-01-01

In today's competitive business climate characterized by uncertain oil markets, responding effectively and speedily to market forces, while maintaining reliable operations, is crucial to a refinery's bottom line. Optimal crude oil scheduling enables cost reduction by using cheaper crudes intelligently, minimizing crude changeovers, and avoiding ship demurrage. So far, only discrete-time formulations have stood up to the challenge of this important, nonlinear problem. A continuous-time formulation would portend numerous advantages, however, existing work in this area has just begun to scratch the surface. In this paper, we present the first complete continuous-time mixed integer linear programming (MILP) formulation for the short-term scheduling of operations in a refinery that receives crude from very large crude carriers via a high-volume single buoy mooring pipeline. This novel formulation accounts for real-world operational practices. We use an iterative algorithm to eliminate the crude composition discrepancy that has proven to be the Achilles heel for existing formulations. While it does not guarantee global optimality, the algorithm needs only MILP solutions and obtains excellent maximum-profit schedules for industrial problems with up to 7 days of scheduling horizon. We also report the first comparison of discrete- vs. continuous-time formulations for this complex problem. (Author)

Time parallelization of advanced operation scenario simulations of ITER plasma

International Nuclear Information System (INIS)

Samaddar, D; Casper, T A; Kim, S H; Houlberg, W A; Berry, L A; Elwasif, W R; Batchelor, D

2013-01-01

This work demonstrates that simulations of advanced burning plasma operation scenarios can be successfully parallelized in time using the parareal algorithm. CORSICA -an advanced operation scenario code for tokamak plasmas is used as a test case. This is a unique application since the parareal algorithm has so far been applied to relatively much simpler systems except for the case of turbulence. In the present application, a computational gain of an order of magnitude has been achieved which is extremely promising. A successful implementation of the Parareal algorithm to codes like CORSICA ushers in the possibility of time efficient simulations of ITER plasmas.

External irradiation of the personnel operating the reactor RA at Vinca in the period 1963-1966

International Nuclear Information System (INIS)

Ninkovic, M.M.; Minincic, Z.

1968-06-01

The paper first gives a survey of the characteristic operations performed on the Vinca reactor RA in which most of the personnel become irradiated. Following is a schematic diagram of the irradiations in the period 1963-1966 in which the reactor was in continual operation. The surveys are given for each month and each year separately, while the irradiated personnel are grouped in several characteristic irradiation dose ranges. In this analysis special emphasis is given to a survey of irradiation of the personnel classified according to their profession, i.e. their post. This kind of analysis is indispensable in planning work, proper disposition of the personnel and undertaking special protective measures for reducing the irradiations (author) [sr

The analysis in real time, during the pre-commissioning period, of the overall plant control system of the CANDU NPP unit

International Nuclear Information System (INIS)

Tapu, C.; Irimia, M.

1994-01-01

The physical processes in the CANDU NPP are controlled by a computer system which, based on the associated package of programmes, performs both the monitoring function at the level of the operational area, and the digital regulation function of the technological systems within the NPP. For an optimal operation of the NPP, in dynamic as well as in stationary regime, the correlation of the direct digital control of the technological systems is very important for the NPP's overall digital control system. Taking into account the fact that during the pre-commissioning period of a CANDU unit it is necessary to test in dynamic regime the performance of the overall digital control function of the NPP, a system of verification and testing in real time was developed, by connecting a micro simulator of the physical process in the NPP to the actual computer system of the unit. The paper presents the methods and techniques used, as well as the results of the tests for various operational modes, which highlight the functioning of the digital control system of the CANDU NPP unit. (Author)

Decomposition analysis of energy consumption for an freeway during its operation period: A case study for Guangdong, China

International Nuclear Information System (INIS)

Li, DuoQi; Wang, DuanYi

2016-01-01

Freeways have become the main subject of energy conservation reviews in China because of their large energy consumption. Decomposition analysis has been widely applied in energy consumption studies. However, most studies have only analyzed the driving forces of energy consumption on the national level, and seldom at smaller levels, e.g. for departments like toll stations and maintenance centers. Based on the characteristics of the freeway operation period, this paper serves as a preliminary attempt at applying the logarithm mean Divisia index method I on the department level to analyze the energy consumption of freeways during the operation period. To elucidate the evolution of energy consumption during the operational period, the logarithm mean Divisia index analysis was performed to disentangle the energy consumption based on a real case in Guangdong from 2005 to 2013. The analyses establish that the traffic volume influences energy consumption. The results show that some departments can influence the total energy consumption. For example, the tunnels and toll stations are key factors that influence the total energy consumption of the whole road. The decomposition in the departments revealed that energy efficiency improvements caused by the use of alternate materials and energy-saving technologies mainly contributed to energy conservation. - Highlights: • Decomposition model was used to analyze energy consumption of freeway management. • This attempt finds the impact of traffic volume on management energy consumption. • Tunnels and toll stations mainly affect the management energy consumption. • Using alternate materials and energy-saving technology improved energy efficiency.

Real Time Wave Forecasting Using Wind Time History and Genetic Programming

Directory of Open Access Journals (Sweden)

A.R. Kambekar

2014-12-01

Full Text Available The significant wave height and average wave period form an essential input for operational activities in ocean and coastal areas. Such information is important in issuing appropriate warnings to people planning any construction or instillation works in the oceanic environment. Many countries over the world routinely collect wave and wind data through a network of wave rider buoys. The data collecting agencies transmit the resulting information online to their registered users through an internet or a web-based system. Operational wave forecasts in addition to the measured data are also made and supplied online to the users. This paper discusses operational wave forecasting in real time mode at locations where wind rather than wave data are continuously recorded. It is based on the time series modeling and incorporates an artificial intelligence technique of genetic programming. The significant wave height and average wave period values are forecasted over a period of 96 hr in future from the observations of wind speed and directions extending to a similar time scale in the past. Wind measurements made by floating buoys at eight different locations around India over a period varying from 1.5 yr to 9.0 yr were considered. The platform of Matlab and C++ was used to develop a graphical user interface that will extend an internet based user-friendly access of the forecasts to any registered user of the data dissemination authority.

Multi-Period Mean-Variance Portfolio Selection with Uncertain Time Horizon When Returns Are Serially Correlated

Directory of Open Access Journals (Sweden)

Ling Zhang

2012-01-01

Full Text Available We study a multi-period mean-variance portfolio selection problem with an uncertain time horizon and serial correlations. Firstly, we embed the nonseparable multi-period optimization problem into a separable quadratic optimization problem with uncertain exit time by employing the embedding technique of Li and Ng (2000. Then we convert the later into an optimization problem with deterministic exit time. Finally, using the dynamic programming approach, we explicitly derive the optimal strategy and the efficient frontier for the dynamic mean-variance optimization problem. A numerical example with AR(1 return process is also presented, which shows that both the uncertainty of exit time and the serial correlations of returns have significant impacts on the optimal strategy and the efficient frontier.

Operator-normalized quantum arrival times in the presence of interactions

International Nuclear Information System (INIS)

Hegerfeldt, G.C.; Seidel, D.; Muga, J.G.; Navarro, B.

2004-01-01

We model ideal arrival-time measurements for free quantum particles and for particles subject to an external interaction by means of a narrow and weak absorbing potential. This approach is related to the operational approach of measuring the first photon emitted from a two-level atom illuminated by a laser. By operator normalizing the resulting time-of-arrival distribution, a distribution is obtained which for freely moving particles not only recovers the axiomatically derived distribution of Kijowski for states with purely positive momenta but is also applicable to general momentum components. For particles interacting with a square barrier the mean arrival time and corresponding 'tunneling time' obtained at the transmission side of the barrier become independent of the barrier width (Hartman effect) for arbitrarily wide barriers, i.e., without the transition to the ultraopaque, classical-like regime dominated by wave packet components above the barrier

Evaluation of 'period-generated' control laws for the time-optimal control of reactor power

International Nuclear Information System (INIS)

Bernard, J.A.

1988-01-01

Time-Optimal control of neutronic power has recently been achieved by developing control laws that determine the actuator mechanism velocity necessary to produce a specified reactor period. These laws are designated as the 'MIT-SNL Period-Generated Minimum Time Control Laws'. Relative to time-optimal response, they function by altering the rate of change of reactivity so that the instantaneous period is stepped from infinity to its minimum allowed value, held at that value until the desired power level is attained, and then stepped back to infinity. The results of a systematic evaluation of these laws are presented. The behavior of each term in the control laws is shown and the capability of these laws to control properly the reactor power is demonstrated. Factors affecting the implementation of these laws, such as the prompt neutron lifetime and the differential reactivity worth of the actuators, are discussed. Finally, the results of an experimental study in which these laws were used to adjust the power of the 5 MWt MIT Research Reactor are shown. The information presented should be of interest to those designing high performance control systems for test, spacecraft, or, in certain instances, commercial reactors

Low-timing-jitter, stretched-pulse passively mode-locked fiber laser with tunable repetition rate and high operation stability

International Nuclear Information System (INIS)

Liu, Yuanshan; Zhang, Jian-Guo; Chen, Guofu; Zhao, Wei; Bai, Jing

2010-01-01

We design a low-timing-jitter, repetition-rate-tunable, stretched-pulse passively mode-locked fiber laser by using a nonlinear amplifying loop mirror (NALM), a semiconductor saturable absorber mirror (SESAM), and a tunable optical delay line in the laser configuration. Low-timing-jitter optical pulses are stably produced when a SESAM and a 0.16 m dispersion compensation fiber are employed in the laser cavity. By inserting a tunable optical delay line between NALM and SESAM, the variable repetition-rate operation of a self-starting, passively mode-locked fiber laser is successfully demonstrated over a range from 49.65 to 50.47 MHz. The experimental results show that the newly designed fiber laser can maintain the mode locking at the pumping power of 160 mW to stably generate periodic optical pulses with width less than 170 fs and timing jitter lower than 75 fs in the 1.55 µm wavelength region, when the fundamental repetition rate of the laser is continuously tuned between 49.65 and 50.47 MHz. Moreover, this fiber laser has a feature of turn-key operation with high repeatability of its fundamental repetition rate in practice

Developing infrared array controller with software real time operating system

Science.gov (United States)

Sako, Shigeyuki; Miyata, Takashi; Nakamura, Tomohiko; Motohara, Kentaro; Uchimoto, Yuka Katsuno; Onaka, Takashi; Kataza, Hirokazu

2008-07-01

Real-time capabilities are required for a controller of a large format array to reduce a dead-time attributed by readout and data transfer. The real-time processing has been achieved by dedicated processors including DSP, CPLD, and FPGA devices. However, the dedicated processors have problems with memory resources, inflexibility, and high cost. Meanwhile, a recent PC has sufficient resources of CPUs and memories to control the infrared array and to process a large amount of frame data in real-time. In this study, we have developed an infrared array controller with a software real-time operating system (RTOS) instead of the dedicated processors. A Linux PC equipped with a RTAI extension and a dual-core CPU is used as a main computer, and one of the CPU cores is allocated to the real-time processing. A digital I/O board with DMA functions is used for an I/O interface. The signal-processing cores are integrated in the OS kernel as a real-time driver module, which is composed of two virtual devices of the clock processor and the frame processor tasks. The array controller with the RTOS realizes complicated operations easily, flexibly, and at a low cost.

Design of real-time operating system software

International Nuclear Information System (INIS)

Stafford, D.L.; Hulbert, A.J.

1976-01-01

Design of real-time data collection and control systems is complicated by problems not found in common sequential programming projects. Timing and synchronization are critical; data collection equipment is often completely foreign to mainframe programming facilities; operating system response to real-time events may be far too slow or too cumbersome. The philosophy at the Inhalation Toxicology Research Institute (ITRI) is to allow the investigators to do as much of their own programming as possible. Inasmuch as programming is not their primary responsibility or area of training, it is unreasonable to assume that they are familiar with the subtleties involved. The problem, therefore, has been to develop a system whereby investigators are able, with minimal consultation, to write, modify and otherwise maintain their own data collection and control programs and to do so with a minimum of destructive interaction with other data collection and control tasks

Operational validation of a multi-period and multi-criteria model conditioning approach for the prediction of rainfall-runoff processes in small forest catchments

Science.gov (United States)

Choi, H.; Kim, S.

2012-12-01

Most of hydrologic models have generally been used to describe and represent the spatio-temporal variability of hydrological processes in the watershed scale. Though it is an obvious fact that hydrological responses have the time varying nature, optimal values of model parameters were normally considered as time invariants or constants in most cases. The recent paper of Choi and Beven (2007) presents a multi-period and multi-criteria model conditioning approach. The approach is based on the equifinality thesis within the Generalised Likelihood Uncertainty Estimation (GLUE) framework. In their application, the behavioural TOPMODEL parameter sets are determined by several performance measures for global (annual) and short (30-days) periods, clustered using a Fuzzy C-means algorithm, into 15 types representing different hydrological conditions. Their study shows a good performance on the calibration of a rainfall-runoff model in a forest catchment, and also gives strong indications that it is uncommon to find model realizations that were behavioural over all multi-periods and all performance measures, and multi-period model conditioning approach may become new effective tool for predictions of hydrological processes in ungauged catchments. This study is a follow-up study on the Choi and Beven's (2007) model conditioning approach to test how the approach is effective for the prediction of rainfall-runoff responses in ungauged catchments. To achieve this purpose, 6 small forest catchments are selected among the several hydrological experimental catchments operated by Korea Forest Research Institute. In each catchment, long-term hydrological time series data varying from 10 to 30 years were available. The areas of the selected catchments range from 13.6 to 37.8 ha, and all areas are covered by coniferous or broad-leaves forests. The selected catchments locate in the southern coastal area to the northern part of South Korea. The bed rocks are Granite gneiss, Granite or

Costs of disposable material in the operating room do not show high correlation with surgical time: Implications for hospital payment.

Science.gov (United States)

Delo, Caroline; Leclercq, Pol; Martins, Dimitri; Pirson, Magali

2015-08-01

The objectives of this study are to analyze the variation of the surgical time and of disposable costs per surgical procedure and to analyze the association between disposable costs and the surgical time. The registration of data was done in an operating room of a 419 bed general hospital, over a period of three months (n = 1556 surgical procedures). Disposable material per procedure used was recorded through a barcode scanning method. The average cost (standard deviation) of disposable material is €183.66 (€183.44). The mean surgical time (standard deviation) is 96 min (63). Results have shown that the homogeneity of operating time and DM costs was quite good per surgical procedure. The correlation between the surgical time and DM costs is not high (r = 0.65). In a context of Diagnosis Related Group (DRG) based hospital payment, it is important that costs information systems are able to precisely calculate costs per case. Our results show that the correlation between surgical time and costs of disposable materials is not good. Therefore, empirical data or itemized lists should be used instead of surgical time as a cost driver for the allocation of costs of disposable materials to patients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Identification of human operator performance models utilizing time series analysis

Science.gov (United States)

Holden, F. M.; Shinners, S. M.

1973-01-01

The results of an effort performed by Sperry Systems Management Division for AMRL in applying time series analysis as a tool for modeling the human operator are presented. This technique is utilized for determining the variation of the human transfer function under various levels of stress. The human operator's model is determined based on actual input and output data from a tracking experiment.

Reactor core operation management system

International Nuclear Information System (INIS)

Sato, Tomomi.

1992-01-01

Among operations of periodical inspection for a nuclear power plant, sequence, time and safety rule, as well as necessary equipments and the number thereof required for each of the operation are determined previously for given operation plannings, relevant to the reactor core operations. Operation items relative to each of coordinates of the reactor core are retrieved and arranged based on specified conditions, to use the operation equipments effectively. Further, a combination of operations, relative to the reactor core coordinates with no physical interference and shortest in accordance with safety rules is judged, and the order and the step of the operation relevant to the entire reactor core operations are planned. After the start of the operation, the necessity for changing the operation sequence is judged depending on the judgement as to whether it is conducted according to the safety rule and the deviation between the plan and the result, based on the information for the progress of each of the operations. Alternatively, the operation sequence and the step to be changed are planned again in accordance with the requirement for the change of the operation planning. Then, the shortest operation time can be planned depending on the simultaneous operation impossible condition and the condition for the operation time zone determined by labor conditions. (N.H.)

Reactor core operation management system

Energy Technology Data Exchange (ETDEWEB)

Sato, Tomomi.

1992-05-28

Among operations of periodical inspection for a nuclear power plant, sequence, time and safety rule, as well as necessary equipments and the number thereof required for each of the operation are determined previously for given operation plannings, relevant to the reactor core operations. Operation items relative to each of coordinates of the reactor core are retrieved and arranged based on specified conditions, to use the operation equipments effectively. Further, a combination of operations, relative to the reactor core coordinates with no physical interference and shortest in accordance with safety rules is judged, and the order and the step of the operation relevant to the entire reactor core operations are planned. After the start of the operation, the necessity for changing the operation sequence is judged depending on the judgement as to whether it is conducted according to the safety rule and the deviation between the plan and the result, based on the information for the progress of each of the operations. Alternatively, the operation sequence and the step to be changed are planned again in accordance with the requirement for the change of the operation planning. Then, the shortest operation time can be planned depending on the simultaneous operation impossible condition and the condition for the operation time zone determined by labor conditions. (N.H.).

Effect of Individual Surgeons and Anesthesiologists on Operating Room Time

NARCIS (Netherlands)

van Eijk, Ruben P A; van Veen-Berkx, Elizabeth; Kazemier, Geert; Eijkemans, Marinus J C

BACKGROUND:: Variability in operating room (OR) time causes overutilization and underutilization of the available ORs. There is evidence that for a given type of procedure, the surgeon is the major source of variability in OR time. The primary aim was to quantify the variability between surgeons and

Ignition and time-dependent fractional power operation of tokamak reactors

International Nuclear Information System (INIS)

Vold, E.L.; Mau, T.K.; Conn, R.W.

1986-01-01

The eventual utilization of a tokamak fusion reactor for commercial power necessitates a thorough understanding of the operational requirements at full and fractional power levels and during transitions from one operating level to another. In this study we examine the role of burn control in maintaining the reactor plasma at equilibrium to avoid thermal runaway during fractional power operation. Because these requirements rely so heavily on the assumptions that govern the plasma transport, this study focuses on time-dependent analyses and a comparison of ignition requirements using a range of energy confinement

Real-time operations intelligence from the user perspective

Energy Technology Data Exchange (ETDEWEB)

Kharbat, Fayez [Saudi Aramco, Dhahran (Saudi Arabia)

2004-07-01

Running a refinery or a chemical plant is a complex business. Planning and scheduling, process control and maintenance require dedicated, multifaceted solutions necessitating highly trained and experienced users. The inevitable system and user specialization results in the proliferation of disparate data sources, incoherent information, inconsistent decisions and the failure to realize corporate objectives - until today. IndX Software Corporation is the de facto market-leading provider of operations intelligence solutions. IndX's XHQ{sup TM} Real-time Operations Intelligence solutions have been selected by many of the world's major corporations in their quest for Operational Excellence and IndX is currently engaged in more than 50 maximizedROI{sup TM} deployments around the world. This paper describes the thinking and technology behind XHQ and the implementation methodology typically employed in deploying an XHQ solution enterprise-wide. This paper will also provide examples of the benefits that users have realized from their implementation of XHQ. (author)

34 CFR 682.418 - Prohibited uses of the assets of the Operating Fund during periods in which the Operating Fund...

Science.gov (United States)

2010-07-01

... or sports events, meals, alcoholic beverages, lodging, rentals, transportation, and gratuities; (4... Operating Fund balance at the time the expenditures are made, unless the agency has provided written notice... to do so by the Secretary. (Approved by the Office of Management and Budget under control number 1840...

Exact dynamics of a one dimensional Bose gas in a periodic time-dependent harmonic trap

Science.gov (United States)

Scopa, Stefano; Unterberger, Jéremie; Karevski, Dragi

2018-05-01

We study the unitary dynamics of a 1D gas of hard-core bosons trapped into a harmonic potential which varies periodically in time with frequency . Such periodic systems can be classified into orbits of different monodromies corresponding to two different physical situations, namely the case in which the bosonic cloud remains stable during the time-evolution and the case where it turns out to be unstable. In the present work we derive in the large particle number limit exact results for the stroboscopic evolution of the energy and particle densities in both physical situations.

A Time-Delayed Mathematical Model for Tumor Growth with the Effect of a Periodic Therapy.

Science.gov (United States)

Xu, Shihe; Wei, Xiangqing; Zhang, Fangwei

2016-01-01

A time-delayed mathematical model for tumor growth with the effect of periodic therapy is studied. The establishment of the model is based on the reaction-diffusion dynamics and mass conservation law and is considered with a time delay in cell proliferation process. Sufficient conditions for the global stability of tumor free equilibrium are given. We also prove that if external concentration of nutrients is large the tumor will not disappear and the conditions under which there exist periodic solutions to the model are also determined. Results are illustrated by computer simulations.

A Time-Delayed Mathematical Model for Tumor Growth with the Effect of a Periodic Therapy

Directory of Open Access Journals (Sweden)

Shihe Xu

2016-01-01

Full Text Available A time-delayed mathematical model for tumor growth with the effect of periodic therapy is studied. The establishment of the model is based on the reaction-diffusion dynamics and mass conservation law and is considered with a time delay in cell proliferation process. Sufficient conditions for the global stability of tumor free equilibrium are given. We also prove that if external concentration of nutrients is large the tumor will not disappear and the conditions under which there exist periodic solutions to the model are also determined. Results are illustrated by computer simulations.

Using mean duration and variation of procedure times to plan a list of surgical operations to fit into the scheduled list time.

Science.gov (United States)

Pandit, Jaideep J; Tavare, Aniket

2011-07-01

It is important that a surgical list is planned to utilise as much of the scheduled time as possible while not over-running, because this can lead to cancellation of operations. We wished to assess whether, theoretically, the known duration of individual operations could be used quantitatively to predict the likely duration of the operating list. In a university hospital setting, we first assessed the extent to which the current ad-hoc method of operating list planning was able to match the scheduled operating list times for 153 consecutive historical lists. Using receiver operating curve analysis, we assessed the ability of an alternative method to predict operating list duration for the same operating lists. This method uses a simple formula: the sum of individual operation times and a pooled standard deviation of these times. We used the operating list duration estimated from this formula to generate a probability that the operating list would finish within its scheduled time. Finally, we applied the simple formula prospectively to 150 operating lists, 'shadowing' the current ad-hoc method, to confirm the predictive ability of the formula. The ad-hoc method was very poor at planning: 50% of historical operating lists were under-booked and 37% over-booked. In contrast, the simple formula predicted the correct outcome (under-run or over-run) for 76% of these operating lists. The calculated probability that a planned series of operations will over-run or under-run was found useful in developing an algorithm to adjust the planned cases optimally. In the prospective series, 65% of operating lists were over-booked and 10% were under-booked. The formula predicted the correct outcome for 84% of operating lists. A simple quantitative method of estimating operating list duration for a series of operations leads to an algorithm (readily created on an Excel spreadsheet, http://links.lww.com/EJA/A19) that can potentially improve operating list planning.

Bioremediation of anthracene contaminated soil in bio-slurry phase reactor operated in periodic discontinuous batch mode

International Nuclear Information System (INIS)

Prasanna, D.; Venkata Mohan, S.; Purushotham Reddy, B.; Sarma, P.N.

2008-01-01

Bioremediation of soil-bound anthracene was studied in a series of bio-slurry phase reactors operated in periodic discontinuous/sequencing batch mode under anoxic-aerobic-anoxic microenvironment using native soil microflora. Five reactors were operated for a total cycle period of 144 h (6 days) at soil loading rate of 16.66 kg soil/m 3 /day at 30 ± 2 o C temperature. The performance of the bioreactors was studied at various substrate loading rates (volumetric substrate loading rate (SLR), 0.1, 0.2 and 0.3 g anthracene/kg soil/day) with and without bioaugmentation (domestic sewage inoculum; 2 x 10 6 CFU/g of soil). Control reactor (without microflora) showed negligible degradation of anthracene due to the absence of biological activity. The performance of the bio-slurry system with respect to anthracene degradation was found to depend on both substrate loading rate and bioaugmentation. Application of bioaugmentation showed positive influence on the rate of degradation of anthracene. Anthracene degradation data was analysed using different kinetic models to understand the mechanism of bioremediation process in the bio-slurry phase system. Variation in pH/oxidation-reduction potential (ORP), soil microflora and oxygen consumption rate correlated well with the substrate degradation pattern observed during soil slurry phase anthracene degradation

40 CFR 60.2685 - What happens during periods of startup, shutdown, and malfunction?

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during CISWI unit startups, shutdowns, or malfunctions. (b) Each...

40 CFR 60.3025 - What happens during periods of startup, shutdown, and malfunction?

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... during periods of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Model Rule—Performance...

Does antegrade JJ stenting affect the total operative time during laparoscopic pyeloplasty?

Science.gov (United States)

Bolat, Mustafa Suat; Çınar, Önder; Akdeniz, Ekrem

2017-12-01

We aimed to show the effect of retrograde JJ stenting and intraoperative antegrade JJ stenting techniques on operative time in patients who underwent laparoscopic pyeloplasty. A total of 34 patients were retrospectively investigated (15 male and 19 female) with ureteropelvic junction obstruction. Of the patients stentized under local anesthesia preoperatively, as a part of surgery, 15 were retrogradely stentized at the beginning of the procedure (Group 1), and 19 were antegradely stentized during the procedure (Group 2). A transperitoneal dismembered pyeloplasty technique was performed in all patients. The two groups were retrospectively compared in terms of complications, the mean total operative time, and the mean stenting times. The mean ages of the patients were 31.5±15.5 and 33.2±15.5 years (p=0.09), and the mean body mass indexes were 25.8±5.6 and 26.2.3±8.4 kg/m 2 in Group 1 and Group 2, respectively. The mean total operative times were 128.9±38.9 min and 112.7±21.9 min (p=0.04); the mean stenting times were 12.6±5.4 min and 3.5±2.4 min (p=0.02); and the mean rates of catheterization-to-total surgery times were 0.1 and 0.03 (p=0.01) in Group 1 and 2, respectively. The mean hospital stays and the mean anastomosis times were similar between the two groups (p>0.05). Antegrade JJ stenting during laparoscopic pyeloplasty significantly decreased the total operative time.

Real-time operation without a real-time operating system for instrument control and data acquisition

Science.gov (United States)

Klein, Randolf; Poglitsch, Albrecht; Fumi, Fabio; Geis, Norbert; Hamidouche, Murad; Hoenle, Rainer; Looney, Leslie; Raab, Walfried; Viehhauser, Werner

2004-09-01

We are building the Field-Imaging Far-Infrared Line Spectrometer (FIFI LS) for the US-German airborne observatory SOFIA. The detector read-out system is driven by a clock signal at a certain frequency. This signal has to be provided and all other sub-systems have to work synchronously to this clock. The data generated by the instrument has to be received by a computer in a timely manner. Usually these requirements are met with a real-time operating system (RTOS). In this presentation we want to show how we meet these demands differently avoiding the stiffness of an RTOS. Digital I/O-cards with a large buffer separate the asynchronous working computers and the synchronous working instrument. The advantage is that the data processing computers do not need to process the data in real-time. It is sufficient that the computer can process the incoming data stream on average. But since the data is read-in synchronously, problems of relating commands and responses (data) have to be solved: The data is arriving at a fixed rate. The receiving I/O-card buffers the data in its buffer until the computer can access it. To relate the data to commands sent previously, the data is tagged by counters in the read-out electronics. These counters count the system's heartbeat and signals derived from that. The heartbeat and control signals synchronous with the heartbeat are sent by an I/O-card working as pattern generator. Its buffer gets continously programmed with a pattern which is clocked out on the control lines. A counter in the I/O-card keeps track of the amount of pattern words clocked out. By reading this counter, the computer knows the state of the instrument or knows the meaning of the data that will arrive with a certain time-tag.

Periodic thermodynamics of laser-driven molecular motor

International Nuclear Information System (INIS)

Li Dan; Zheng Wenwei; Wang Zhisong

2008-01-01

Operation of a laser-driven nano-motor inevitably generates a non-trivial amount of heat, which can possibly lead to instability or even hinder the motor's continual running. This work quantitatively examines the overheating problem for a recently proposed laser-operated molecular locomotive. We present a single-molecule cooling theory, in which molecular details of the locomotive system are explicitly treated. This theory is able to quantitatively predict cooling efficiency for various candidates of molecular systems for the locomotive, and also suggests concrete strategies for improving the locomotive's cooling. It is found that water environment is able to cool the hot locomotive down to room temperature within 100 picoseconds after photon absorption. This cooling time is a few orders of magnitude shorter than the typical time for laser operation, effectively preventing any overheating for the nano-locomotive. However, when the cooling is less effective in non-aqueous environment, residual heat may build up. A continuous running of the motor will then lead to a periodic thermodynamics, which is a common character of many laser-operated nano-devices

Schroedinger operators - geometric estimates in terms of the occupation time

International Nuclear Information System (INIS)

Demuth, M.; Kirsch, W.; McGillivray, I.

1995-01-01

The difference of Schroedinger and Dirichlet semigroups is expressed in terms of the Laplace transform of the Brownian motion occupation time. This implies quantitative upper and lower bounds for the operator norms of the corresponding resolvent differences. One spectral theoretical consequence is an estimate for the eigenfunction for a Schroedinger operator in a ball where the potential is given as a cone indicator function. 12 refs

Hanford Site Air Operating Permit Semiannual Report for the period July 21 2001 Thru December 31 2001

International Nuclear Information System (INIS)

GREEN, W.E.

2002-01-01

The Hanford Site Air Operating Permit (AOP), Number 00-05-006, became effective on July 2, 2001. One condition contained in the AOP, ''Standard Terms and Conditions'', Section 4.3.3, is the requirement to submit semiannual reports by March 15th and August 15th each year, which are certified for truth and accuracy by a Responsible Official. This first semiannual report contains information for the period from July 2, 2001 through December 31, 2001. Hereafter, the March 15th semiannual report will contain information for the period from July 1 through December 31. The semiannual report submitted by August 15th will contain information for the period from January 1 through June 30. Copies of the semiannual reports are transmitted to the Washington State Department of Ecology (Ecology), the Washington State Department of Health (WDOH), the Benton Clean Air Authority (BCAA), and the U.S. Environmental Protection Agency (EPA), Region 10. For the applicable reporting period, AOP, ''Standard Terms and Conditions'', Section 4.3.3, identifies the following: (1) Each semiannual report will provide a reference to deviation reports submitted to the regulatory agencies as required by Section 4.5, ''Permit Deviation Reporting''. (2) Each semiannual report will consist of reports of any required monitoring not submitted previously to the agencies or a reference to reports of required monitoring that were submitted during the reporting period. (3) Each semiannual report will contain a summary of any substantiated air emission complaint investigation(s) required in Table 1.2 of AOP, Attachment 1, and issued during the reporting period (4) For all minor radioactive emission points (potential to emit <0.1 mrem to the maximally exposed individual) listed in AOP, Attachment 2. Tables 1.2, 1.3 and 2.1. each semiannual report will confirm that any required monitoring was conducted to verify low emissions during the reporting period. The data derived from that monitoring will be reported

Hanford Site Air Operating Permit Semiannual Report for the period July 21 2001 Thru December 31 2001

Energy Technology Data Exchange (ETDEWEB)

GREEN, W.E.

2002-02-01

The Hanford Site Air Operating Permit (AOP), Number 00-05-006, became effective on July 2, 2001. One condition contained in the AOP, ''Standard Terms and Conditions'', Section 4.3.3, is the requirement to submit semiannual reports by March 15th and August 15th each year, which are certified for truth and accuracy by a Responsible Official. This first semiannual report contains information for the period from July 2, 2001 through December 31, 2001. Hereafter, the March 15th semiannual report will contain information for the period from July 1 through December 31. The semiannual report submitted by August 15th will contain information for the period from January 1 through June 30. Copies of the semiannual reports are transmitted to the Washington State Department of Ecology (Ecology), the Washington State Department of Health (WDOH), the Benton Clean Air Authority (BCAA), and the U.S. Environmental Protection Agency (EPA), Region 10. For the applicable reporting period, AOP, ''Standard Terms and Conditions'', Section 4.3.3, identifies the following: (1) Each semiannual report will provide a reference to deviation reports submitted to the regulatory agencies as required by Section 4.5, ''Permit Deviation Reporting''. (2) Each semiannual report will consist of reports of any required monitoring not submitted previously to the agencies or a reference to reports of required monitoring that were submitted during the reporting period. (3) Each semiannual report will contain a summary of any substantiated air emission complaint investigation(s) required in Table 1.2 of AOP, Attachment 1, and issued during the reporting period (4) For all minor radioactive emission points (potential to emit <0.1 mrem to the maximally exposed individual) listed in AOP, Attachment 2. Tables 1.2, 1.3 and 2.1. each semiannual report will confirm that any required monitoring was conducted to verify low emissions during the reporting

Reliability of fitness tests using methods and time periods common in sport and occupational management.

Science.gov (United States)

Burnstein, Bryan D; Steele, Russell J; Shrier, Ian

2011-01-01

Fitness testing is used frequently in many areas of physical activity, but the reliability of these measurements under real-world, practical conditions is unknown. To evaluate the reliability of specific fitness tests using the methods and time periods used in the context of real-world sport and occupational management. Cohort study. Eighteen different Cirque du Soleil shows. Cirque du Soleil physical performers who completed 4 consecutive tests (6-month intervals) and were free of injury or illness at each session (n = 238 of 701 physical performers). Performers completed 6 fitness tests on each assessment date: dynamic balance, Harvard step test, handgrip, vertical jump, pull-ups, and 60-second jump test. We calculated the intraclass coefficient (ICC) and limits of agreement between baseline and each time point and the ICC over all 4 time points combined. Reliability was acceptable (ICC > 0.6) over an 18-month time period for all pairwise comparisons and all time points together for the handgrip, vertical jump, and pull-up assessments. The Harvard step test and 60-second jump test had poor reliability (ICC < 0.6) between baseline and other time points. When we excluded the baseline data and calculated the ICC for 6-month, 12-month, and 18-month time points, both the Harvard step test and 60-second jump test demonstrated acceptable reliability. Dynamic balance was unreliable in all contexts. Limit-of-agreement analysis demonstrated considerable intraindividual variability for some tests and a learning effect by administrators on others. Five of the 6 tests in this battery had acceptable reliability over an 18-month time frame, but the values for certain individuals may vary considerably from time to time for some tests. Specific tests may require a learning period for administrators.

A virtual reality-based method of decreasing transmission time of visual feedback for a tele-operative robotic catheter operating system.

Science.gov (United States)

Guo, Jin; Guo, Shuxiang; Tamiya, Takashi; Hirata, Hideyuki; Ishihara, Hidenori

2016-03-01

An Internet-based tele-operative robotic catheter operating system was designed for vascular interventional surgery, to afford unskilled surgeons the opportunity to learn basic catheter/guidewire skills, while allowing experienced physicians to perform surgeries cooperatively. Remote surgical procedures, limited by variable transmission times for visual feedback, have been associated with deterioration in operability and vascular wall damage during surgery. At the patient's location, the catheter shape/position was detected in real time and converted into three-dimensional coordinates in a world coordinate system. At the operation location, the catheter shape was reconstructed in a virtual-reality environment, based on the coordinates received. The data volume reduction significantly reduced visual feedback transmission times. Remote transmission experiments, conducted over inter-country distances, demonstrated the improved performance of the proposed prototype. The maximum error for the catheter shape reconstruction was 0.93 mm and the transmission time was reduced considerably. The results were positive and demonstrate the feasibility of remote surgery using conventional network infrastructures. Copyright © 2015 John Wiley & Sons, Ltd.

A journey to zero: reduction of post-operative cesarean surgical site infections over a five-year period.

Science.gov (United States)

Hickson, Evelyn; Harris, Jeanette; Brett, David

2015-04-01

Surgical site infections (SSI) are a substantial concern for cesarean deliveries in which a surgical site complication is most unwelcome for a mother with a new infant. Steps taken pre- and post-operatively to reduce the number of complications may be of substantial benefit clinically, economically, and psychologically. A risk-based approach to incision management was developed and implemented for all cesarean deliveries at our institution. A number of incremental interventions for low-risk and high-risk patients including pre-operative skin preparations, standardized pre- and post-operative protocols, post-operative nanocrystalline silver anti-microbial barrier dressings, and incisional negative pressure wound therapy (NPWT) were implemented sequentially over a 5-y period. A systematic clinical chart review of 4,942 patients spanning all cesarean deliveries between 2007-2012 was performed to determine what effects the interventions had on the rate of SSI for cesarean deliveries. The percentage of SSI was reduced from 2.13% (2007) to 0.10% (2012) (poperative SSIs were avoided: A total cost saving of nearly $5,000,000. Applying a clinical algorithm for assessing the risk of surgical site complication and making recommendations on pre-operative and post-operative incision management can result in a substantial and sustainable reduction in cesarean SSI.

On periodically driven AdS/CFT

CERN Document Server

Auzzi, Roberto; Gudnason, Sven Bjarke; Rabinovici, Eliezer

2013-01-01

We use the AdS/CFT correspondence to study a thermally isolated conformal field theory in four dimensions which undergoes a repeated deformation by an external periodic time-dependent source coupled to an operator of dimension Delta. The initial state of the theory is taken to be at a finite temperature. We compute the energy dissipated in the system as a function of the frequency and of the dimension Delta of the perturbing operator. This is done in the linear response regime. In order to study the details of thermalization in the dual field theory, the leading-order backreaction on the AdS black brane metric is computed. The evolution of the event and the apparent horizons is monitored; the increase of area in each cycle coincides with the increase in the equilibrium entropy corresponding to the amount of energy dissipated. The time evolution of the entanglement entropy of a spherical region and that of the two-points function of a probe operator with a large dimension are also inspected; we find a delay in...

ISS Operations Cost Reductions Through Automation of Real-Time Planning Tasks

Science.gov (United States)

Hall, Timothy A.

2011-01-01

In 2008 the Johnson Space Center s Mission Operations Directorate (MOD) management team challenged their organization to find ways to reduce the costs of International Space station (ISS) console operations in the Mission Control Center (MCC). Each MOD organization was asked to identify projects that would help them attain a goal of a 30% reduction in operating costs by 2012. The MOD Operations and Planning organization responded to this challenge by launching several software automation projects that would allow them to greatly improve ISS console operations and reduce staffing and operating costs. These projects to date have allowed the MOD Operations organization to remove one full time (7 x 24 x 365) ISS console position in 2010; with the plan of eliminating two full time ISS console support positions by 2012. This will account for an overall 10 EP reduction in staffing for the Operations and Planning organization. These automation projects focused on utilizing software to automate many administrative and often repetitive tasks involved with processing ISS planning and daily operations information. This information was exchanged between the ground flight control teams in Houston and around the globe, as well as with the ISS astronaut crew. These tasks ranged from managing mission plan changes from around the globe, to uploading and downloading information to and from the ISS crew, to even more complex tasks that required multiple decision points to process the data, track approvals and deliver it to the correct recipient across network and security boundaries. The software solutions leveraged several different technologies including customized web applications and implementation of industry standard web services architecture between several planning tools; as well as a engaging a previously research level technology (TRL 2-3) developed by Ames Research Center (ARC) that utilized an intelligent agent based system to manage and automate file traffic flow

Real-time risk assessment of operational events

International Nuclear Information System (INIS)

Perryman, L.J.; Foster, N.A.S.; Nicholls, D.R.; Grobbelaar, J.F.

1996-01-01

Probabilistic risk assessment (PRA) has always been fundamental to the licensing process of Koeberg nuclear power station. Furthermore, over the past 8 years PRA has assisted in many areas of operation. One of these areas is the real-time assessment of abnormal operating events. Over the years, considerable experience has been gained in using PRA to improve plant safety and performance. This paper presents some of the insights obtained in using PRA in such a dynamic role and demonstrates that, by developing and using the plant-specific 'living' PRA, considerable safety and financial gains can be obtained. These insights specifically concern the prerequisites before optimal use of a plant-specific 'living' PRA can be made. Finally, examples are presented of occurrences when PRA was used to improve plant safety and performance. These examples serve to demonstrate the advantages that can be obtained if sufficient resources are placed at the disposal of the PRA team. (orig.)

A cost and time analysis of laryngology procedures in the endoscopy suite versus the operating room.

Science.gov (United States)

Hillel, Alexander T; Ochsner, Matthew C; Johns, Michael M; Klein, Adam M

2016-06-01

To assess the costs, charges, reimbursement, and efficiency of performing awake laryngology procedures in an endoscopy suite (ES) compared with like procedures performed in the operating room (OR). Retrospective review of billing records. Cost, charges, and reimbursements for the hospital, surgeon, and anesthesiologist were compared between ES injection laryngoplasty and laser excision procedures and matched case controls in the OR. Time spent in 1) the preoperative unit, 2) the operating or endoscopy suite, and 3) recovery unit were compared between OR and ES procedures. Hospital expenses were significantly less for ES procedures when compared to OR procedures. Reimbursement was similar for ES and OR injection laryngoplasty, though greater for OR laser excisions. Net balance (reimbursement-expenses) was greater for ES procedures. A predictive model of payer costs over a 3-year period showed similar costs for ES and OR laser procedures and reduced costs for ES compared to OR injection laryngoplasty. Times spent preoperatively and the procedure were significantly less for ES procedures. For individual laryngology procedures, the ES reduces time and costs compared to the OR, increasing otolaryngologist and hospital efficiency. This reveals cost and time savings of ES injection laryngoplasty, which occurs at a similar frequency as OR injection laryngoplasty. Given the increased frequency for ES laser procedures, total costs are similar for ES and OR laser excision of papilloma, which usually require repeated procedures. When regulated office space is unavailable, endoscopy rooms represent an alternative setting for unsedated laryngology procedures. NA Laryngoscope, 126:1385-1389, 2016. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

Finite-element time evolution operator for the anharmonic oscillator

Science.gov (United States)

Milton, Kimball A.

1995-01-01

The finite-element approach to lattice field theory is both highly accurate (relative errors approximately 1/N(exp 2), where N is the number of lattice points) and exactly unitary (in the sense that canonical commutation relations are exactly preserved at the lattice sites). In this talk I construct matrix elements for dynamical variables and for the time evolution operator for the anharmonic oscillator, for which the continuum Hamiltonian is H = p(exp 2)/2 + lambda q(exp 4)/4. Construction of such matrix elements does not require solving the implicit equations of motion. Low order approximations turn out to be extremely accurate. For example, the matrix element of the time evolution operator in the harmonic oscillator ground state gives a results for the anharmonic oscillator ground state energy accurate to better than 1 percent, while a two-state approximation reduces the error to less than 0.1 percent.

The Sensitivity of Income Polarization - Time, length of accounting periods, equivalence scales, and income definitions

DEFF Research Database (Denmark)

Azhar, Hussain

This study looks at polarization and its components’ sensitivity to assumptions about equivalence scales, income definition, ethical income distribution parameters, and the income accounting period. A representative sample of Danish individual incomes from 1984 to 2002 is utilised. Results show...... that polarization has increased over time, regardless of the applied measure, when the last part of the period is compared to the first part of the period. Primary causes being increased inequality (alienation) and faster income growth among high incomes relative to those in the middle of the distribution....... Increasing the accounting period confirms the reduction in inequality found for shorter periods, but polarization is virtually unchanged, because income group identification increases. Applying different equivalence scales does not change polarization ranking for different years, but identification ranks...

High-order fuzzy time-series based on multi-period adaptation model for forecasting stock markets

Science.gov (United States)

Chen, Tai-Liang; Cheng, Ching-Hsue; Teoh, Hia-Jong

2008-02-01

Stock investors usually make their short-term investment decisions according to recent stock information such as the late market news, technical analysis reports, and price fluctuations. To reflect these short-term factors which impact stock price, this paper proposes a comprehensive fuzzy time-series, which factors linear relationships between recent periods of stock prices and fuzzy logical relationships (nonlinear relationships) mined from time-series into forecasting processes. In empirical analysis, the TAIEX (Taiwan Stock Exchange Capitalization Weighted Stock Index) and HSI (Heng Seng Index) are employed as experimental datasets, and four recent fuzzy time-series models, Chen’s (1996), Yu’s (2005), Cheng’s (2006) and Chen’s (2007), are used as comparison models. Besides, to compare with conventional statistic method, the method of least squares is utilized to estimate the auto-regressive models of the testing periods within the databases. From analysis results, the performance comparisons indicate that the multi-period adaptation model, proposed in this paper, can effectively improve the forecasting performance of conventional fuzzy time-series models which only factor fuzzy logical relationships in forecasting processes. From the empirical study, the traditional statistic method and the proposed model both reveal that stock price patterns in the Taiwan stock and Hong Kong stock markets are short-term.

Periodic Solutions and S-Asymptotically Periodic Solutions to Fractional Evolution Equations

Directory of Open Access Journals (Sweden)

Jia Mu

2017-01-01

Full Text Available This paper deals with the existence and uniqueness of periodic solutions, S-asymptotically periodic solutions, and other types of bounded solutions for some fractional evolution equations with the Weyl-Liouville fractional derivative defined for periodic functions. Applying Fourier transform we give reasonable definitions of mild solutions. Then we accurately estimate the spectral radius of resolvent operator and obtain some existence and uniqueness results.

Synthesis of Biochemical Applications on Digital Microfluidic Biochips with Operation Execution Time Variability

DEFF Research Database (Denmark)

Alistar, Mirela; Pop, Paul

2015-01-01

that each biochemical operation in an application is characterized by a worst-case execution time (wcet). However, during the execution of the application, due to variability and randomness in biochemical reactions, operations may finish earlier than their wcetswcets, resulting in unexploited slack...... in the schedule. In this paper, we first propose an online synthesis strategy that re-synthesizes the application at runtime when operations experience variability in their execution time, exploiting thus the slack to obtain shorter application completion times. We also propose a quasi-static synthesis strategy...... approaches have been proposed for the synthesis of digital microfluidic biochips, which, starting from a biochemical application and a given biochip architecture, determine the allocation, resource binding, scheduling, placement and routing of the operations in the application. Researchers have assumed...

[Evaluation of radiation exposure of personnel in an orthopaedic and trauma operation theatre using the new real-time dosimetry system "dose aware"].

Science.gov (United States)

Müller, M C; Strauss, A; Pflugmacher, R; Nähle, C P; Pennekamp, P H; Burger, C; Wirtz, D C

2014-08-01

There is a positive correlation between operation time and staff exposure to radiation during intraoperative use of C-arm fluoroscopy. Due to harmful effects of exposure to long-term low-dose radiation for both the patient and the operating team it should be kept to a minimum. AIM of this study was to evaluate a novel dosimeter system called Dose Aware® (DA) enabling radiation exposure feedback of the personal in an orthopaedic and trauma operation theatre in real-time. Within a prospective study over a period of four month, DA was applied by the operation team during 104 orthopaedic and trauma operations in which the C-arm fluoroscope was used in 2D-mode. During ten operation techniques, radiation exposure of the surgeon, the first assistant, the theatre nurse and the anaesthesiologist was evaluated. Seventy-three operations were analysed. The surgeon achieved the highest radiation exposure during dorsolumbar spinal osteosynthesis, kyphoplasty and screw fixation of sacral fractures. The first assistant received a higher radiation exposure compared to the surgeon during plate osteosynthesis of distal radius fractures (157 %), intramedullary nailing of pertrochanteric fractures (143 %) and dorsolumbar spinal osteosynthesis (240 %). During external fixation of ankle fractures (68 %) and screw fixation of sacral fractures (66 %) radiation exposure of the theatre nurse exceeded 50 % of the surgeon's radiation exposure. During plate osteosynthesis of distal radius fractures (157 %) and intramedullary splinting of clavicular fractures (115 %), the anaesthesiologist received a higher radiation exposure than the surgeon. The novel dosimeter system DA provides real-time radiation exposure feedback of the personnel in an orthopaedic and trauma operation theatre for the first time. Data of this study demonstrate that radiation exposure of the personnel depends on the operation type. The first assistant, the theatre nurse and the anaesthesiologist might be

Numerical Solution of Time-Dependent Problems with a Fractional-Power Elliptic Operator

Science.gov (United States)

Vabishchevich, P. N.

2018-03-01

A time-dependent problem in a bounded domain for a fractional diffusion equation is considered. The first-order evolution equation involves a fractional-power second-order elliptic operator with Robin boundary conditions. A finite-element spatial approximation with an additive approximation of the operator of the problem is used. The time approximation is based on a vector scheme. The transition to a new time level is ensured by solving a sequence of standard elliptic boundary value problems. Numerical results obtained for a two-dimensional model problem are presented.

Feedback effect of human physical and psychological adaption on time period of thermal adaption in naturally ventilated building

DEFF Research Database (Denmark)

liu, weiwei; Huangfu, Hao; Xiong, Jing

2014-01-01

This study proposed a method to determine time period of thermal adaption for occupants in naturally ventilated building, and analyzed the synergistic and separate feedback effect of the physical and psychological adaption modes on the time period of thermal adaption. Using the method, the values...... of the time period of thermal adaption were obtained on the basis of the data from a long-term field survey conducted in two typical naturally ventilated offices located in Changsha, China. The results showed that the occupants need to take 4.25 days to fully adapt to a step-change in outdoor air temperature...

Applied Operations Research: Operator's Assistant

Science.gov (United States)

Cole, Stuart K.

2015-01-01

NASA operates high value critical equipment (HVCE) that requires trouble shooting, periodic maintenance and continued monitoring by Operations staff. The complexity HVCE and information required to maintain and trouble shoot HVCE to assure continued mission success as paper is voluminous. Training on new HVCE is commensurate with the need for equipment maintenance. LaRC Research Directorate has undertaken a proactive research to support Operations staff by initiation of the development and prototyping an electronic computer based portable maintenance aid (Operator's Assistant). This research established a goal with multiple objectives and a working prototype was developed. The research identified affordable solutions; constraints; demonstrated use of commercial off the shelf software; use of the US Coast Guard maintenance solution; NASA Procedure Representation Language; and the identification of computer system strategies; where these demonstrations and capabilities support the Operator, and maintenance. The results revealed validation against measures of effectiveness and overall proved a substantial training and capability sustainment tool. The research indicated that the OA could be deployed operationally at the LaRC Compressor Station with an expectation of satisfactorily results and to obtain additional lessons learned prior to deployment at other LaRC Research Directorate Facilities. The research revealed projected cost and time savings.

Time Management in the Operating Room: An Analysis of the Dedicated Minimally Invasive Surgery Suite

Science.gov (United States)

Hsiao, Kenneth C.; Machaidze, Zurab

2004-01-01

Background: Dedicated minimally invasive surgery suites are available that contain specialized equipment to facilitate endoscopic surgery. Laparoscopy performed in a general operating room is hampered by the multitude of additional equipment that must be transported into the room. The objective of this study was to compare the preparation times between procedures performed in traditional operating rooms versus dedicated minimally invasive surgery suites to see whether operating room efficiency is improved in the specialized room. Methods: The records of 50 patients who underwent laparoscopic procedures between September 2000 and April 2002 were retrospectively reviewed. Twenty-three patients underwent surgery in a general operating room and 18 patients in an minimally invasive surgery suite. Nine patients were excluded because of cystoscopic procedures undergone prior to laparoscopy. Various time points were recorded from which various time intervals were derived, such as preanesthesia time, anesthesia induction time, and total preparation time. A 2-tailed, unpaired Student t test was used for statistical analysis. Results: The mean preanesthesia time was significantly faster in the minimally invasive surgery suite (12.2 minutes) compared with that in the traditional operating room (17.8 minutes) (P=0.013). Mean anesthesia induction time in the minimally invasive surgery suite (47.5 minutes) was similar to time in the traditional operating room (45.7 minutes) (P=0.734). The average total preparation time for the minimally invasive surgery suite (59.6 minutes) was not significantly faster than that in the general operating room (63.5 minutes) (P=0.481). Conclusion: The amount of time that elapses between the patient entering the room and anesthesia induction is statically shorter in a dedicated minimally invasive surgery suite. Laparoscopic surgery is performed more efficiently in a dedicated minimally invasive surgery suite versus a traditional operating room. PMID

Real-Time Science Operations to Support a Lunar Polar Volatiles Rover Mission

Science.gov (United States)

Heldmann, Jennifer L.; Colaprete, Anthony; Elphic, Richard C.; Mattes, Greg; Ennico, Kimberly; Fritzler, Erin; Marinova, Margarita M.; McMurray, Robert; Morse, Stephanie; Roush, Ted L.;

The effect of implant macro-thread design on implant stability in the early post-operative period: a randomized, controlled pilot study.

Science.gov (United States)

McCullough, Jeffrey J; Klokkevold, Perry R

2017-10-01

Available literature suggests there is a transient drop in implant stability from approximately week 0 to week 3-4 as a result of peri-implant bone remodeling as it transitions from a primary, mechanical stability to a secondary, biological stability. Research investigating the influence of macro-thread design on this process is scant. The specific aim of this study was to evaluate the role of macro-thread design on implant stability in the early post-operative healing period using resonance frequency analysis (RFA). Seven patients, each missing at least two posterior teeth in the same arch, were included in the study. Three patients qualified for four implants resulting in a total of 10 matched pairs. All sites were healed (>6 months), non-grafted sites with sufficient bone to place implants. Each site in a matched pair was randomly assigned to receive either a control (Megagen EZ Plus Internal; EZ) or test (Megagen AnyRidge; AR) implant. The test implant incorporates a novel thread design with a wide thread depth and increased thread pitch. RFA was used to determine implant stability quotient (ISQ) values for each implant at the time of placement and weekly for the first 8 weeks. Implants consistently achieved a relatively high insertion torque (30-45 N/cm) and high initial ISQ value (79.8 ± 1.49). Baseline ISQ values for test (AR; 79.55 ± 1.61) and control (EZ; 80.05 ± 1.37) implants were similar. A general pattern of stability from baseline through all eight follow-up evaluations was observed for the test implants. A pattern of decreasing ISQ values was observed for the control implants across the early follow-up evaluations up to week four, where the value plateaued. There was a statistically significant main effect due to implant type (P implant type and time (P implants performed differently at certain time points. Within the limitations of this study, macro-thread design appears to play a role in implant stability in the early post-operative

Simulation-based multidisciplinary team training decreases time to critical operations for trauma patients.

Science.gov (United States)

Murphy, Margaret; Curtis, Kate; Lam, Mary K; Palmer, Cameron S; Hsu, Jeremy; McCloughen, Andrea

2018-05-01

Simulation has been promoted as a platform for training trauma teams. However, it is not clear if this training has an impact on health service delivery and patient outcomes. This study evaluates the association between implementation of a simulation based multidisciplinary trauma team training program at a metropolitan trauma centre and subsequent patient outcomes. This was a retrospective review of trauma registry data collected at an 850-bed Level 1 Adult Trauma Centre in Sydney, Australia. Two concurrent four-year periods, before and after implementation of a simulation based multidisciplinary trauma team training program were compared for differences in time to critical operations, Emergency Department (ED) length of stay (LOS) and patient mortality. There were 2389 major trauma patients admitted to the hospital during the study, 1116 in the four years preceding trauma team training (the PREgroup) and 1273 in the subsequent 4 years (the POST group). There were no differences between the groups with respect to gender, body region injured, incidence of polytrauma, and pattern of arrival to ED. The POST group was older (median age 54 versus 43 years, p team training was associated with a reduction in time to critical operation while overall ED length of stay increased. Simulation is promoted as a platform for training teams; but the complexity of trauma care challenges efforts to demonstrate direct links between multidisciplinary team training and improved outcomes. There remain considerable gaps in knowledge as to how team training impacts health service delivery and patient outcomes. Retrospective comparative therapeutic/care management study, Level III evidence. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

Variation of Time Domain Failure Probabilities of Jack-up with Wave Return Periods

Science.gov (United States)

Idris, Ahmad; Harahap, Indra S. H.; Ali, Montassir Osman Ahmed

2018-04-01

This study evaluated failure probabilities of jack up units on the framework of time dependent reliability analysis using uncertainty from different sea states representing different return period of the design wave. Surface elevation for each sea state was represented by Karhunen-Loeve expansion method using the eigenfunctions of prolate spheroidal wave functions in order to obtain the wave load. The stochastic wave load was propagated on a simplified jack up model developed in commercial software to obtain the structural response due to the wave loading. Analysis of the stochastic response to determine the failure probability in excessive deck displacement in the framework of time dependent reliability analysis was performed by developing Matlab codes in a personal computer. Results from the study indicated that the failure probability increases with increase in the severity of the sea state representing a longer return period. Although the results obtained are in agreement with the results of a study of similar jack up model using time independent method at higher values of maximum allowable deck displacement, it is in contrast at lower values of the criteria where the study reported that failure probability decreases with increase in the severity of the sea state.

Time-consistent actuarial valuations

NARCIS (Netherlands)

Pelsser, A.A.J.; Salahnejhad Ghalehjooghi, A.

2016-01-01

Time-consistent valuations (i.e. pricing operators) can be created by backward iteration of one-period valuations. In this paper we investigate the continuous-time limits of well-known actuarial premium principles when such backward iteration procedures are applied. This method is applied to an

Controlled time of arrival windows for already initiated energy-neutral continuous descent operations

OpenAIRE

Dalmau Codina, Ramon; Prats Menéndez, Xavier

2017-01-01

Continuous descent operations with controlled times of arrival at one or several metering fixes could enable environmentally friendly procedures without compromising terminal airspace capacity. This paper focuses on controlled time of arrival updates once the descent has been already initiated, assessing the feasible time window (and associated fuel consumption) of continuous descent operations requiring neither thrust nor speed-brake usage along the whole descent (i.e. only elevator control ...

Periodic Safety Review of Nuclear Power Plants: Experience of Member States

International Nuclear Information System (INIS)

2010-04-01

Routine reviews of nuclear power plant operation (including modifications to hardware and procedures, operating experience, plant management and personnel competence) and special reviews following major events of safety significance are the primary means of safety verification. In addition, many Member States of the IAEA have initiated systematic safety reassessments, termed periodic safety reviews, of nuclear power plants, to assess the cumulative effects of plant ageing and plant modifications, operating experience, technical developments and siting aspects. The reviews include an assessment of plant design and operation against current safety standards and practices, and they have the objective of ensuring a high level of safety throughout the plant's operating lifetime. They are complementary to the routine and special safety reviews and do not replace them. Periodic safety reviews of nuclear power plants are considered an effective way to obtain an overall view of actual plant safety, and to determine reasonable and practical modifications that should be made in order to maintain a high level of safety. They can be used as a means of identifying time limiting features of the plant in order to determine nuclear power plant operation beyond the designed lifetime. The periodic safety review process can be used to support the decision making process for long term operation or licence renewal. Since 1994, the use of periodic safety reviews by Member States has substantially broadened and confirmed its benefits. Periodic safety review results have, for example, been used by some Member States to help provide a basis for continued operation beyond the current licence term, to communicate more effectively with stakeholders regarding nuclear power plant safety, and to help identify changes to plant operation that enhance safety. This IAEA-TECDOC is intended to assist Member States in the implementation of a periodic safety review. This publication complements the

Model Predictive Control application for real time operation of controlled structures for the Water Authority Noorderzijlvest, The Netherlands

Science.gov (United States)

van Heeringen, Klaas-Jan; Gooijer, Jan; Knot, Floris; Talsma, Jan

2015-04-01

In the Netherlands, flood protection has always been a key issue to protect settlements against storm surges and riverine floods. Whereas flood protection traditionally focused on structural measures, nowadays the availability of meteorological and hydrological forecasts enable the application of more advanced real-time control techniques for operating the existing hydraulic infrastructure in an anticipatory and more efficient way. Model Predictive Control (MPC) is a powerful technique to derive optimal control variables with the help of model based predictions evaluated against a control objective. In a project for the regional water authority Noorderzijlvest in the north of the Netherlands, it has been shown that MPC can increase the safety level of the system during flood events by an anticipatory pre-release of water. Furthermore, energy costs of pumps can be reduced by making tactical use of the water storage and shifting pump activities during normal operating conditions to off-peak hours. In this way cheap energy is used in combination of gravity flow through gates during low tide periods. MPC has now been implemented for daily operational use of the whole water system of the water authority Noorderzijlvest. The system developed to a real time decision support system which not only supports the daily operation but is able to directly implement the optimal control settings at the structures. We explain how we set-up and calibrated a prediction model (RTC-Tools) that is accurate and fast enough for optimization purposes, and how we integrated it in the operational flood early warning system (Delft-FEWS). Beside the prediction model, the weights and the factors of the objective function are an important element of MPC, since they shape the control objective. We developed special features in Delft-FEWS to allow the operators to adjust the objective function in order to meet changing requirements and to evaluate different control strategies.

Army Secure Operating System: Information Security for Real Time Systems

National Research Council Canada - National Science Library

Anderson, Eric

1984-01-01

The Army Secure Operating System (ASOS) project, under the management of the U.S. Army CECOM organization, will provide real time systems software necessary for fielding modern Battlefield Automation Systems...

Stochastic model stationarization by eliminating the periodic term and its effect on time series prediction

Science.gov (United States)

Moeeni, Hamid; Bonakdari, Hossein; Fatemi, Seyed Ehsan

2017-04-01

Because time series stationarization has a key role in stochastic modeling results, three methods are analyzed in this study. The methods are seasonal differencing, seasonal standardization and spectral analysis to eliminate the periodic effect on time series stationarity. First, six time series including 4 streamflow series and 2 water temperature series are stationarized. The stochastic term for these series obtained with ARIMA is subsequently modeled. For the analysis, 9228 models are introduced. It is observed that seasonal standardization and spectral analysis eliminate the periodic term completely, while seasonal differencing maintains seasonal correlation structures. The obtained results indicate that all three methods present acceptable performance overall. However, model accuracy in monthly streamflow prediction is higher with seasonal differencing than with the other two methods. Another advantage of seasonal differencing over the other methods is that the monthly streamflow is never estimated as negative. Standardization is the best method for predicting monthly water temperature although it is quite similar to seasonal differencing, while spectral analysis performed the weakest in all cases. It is concluded that for each monthly seasonal series, seasonal differencing is the best stationarization method in terms of periodic effect elimination. Moreover, the monthly water temperature is predicted with more accuracy than monthly streamflow. The criteria of the average stochastic term divided by the amplitude of the periodic term obtained for monthly streamflow and monthly water temperature were 0.19 and 0.30, 0.21 and 0.13, and 0.07 and 0.04 respectively. As a result, the periodic term is more dominant than the stochastic term for water temperature in the monthly water temperature series compared to streamflow series.

A delay time model for a mission-based system subject to periodic and random inspection and postponed replacement

International Nuclear Information System (INIS)

Yang, Li; Ma, Xiaobing; Zhai, Qingqing; Zhao, Yu

2016-01-01

We propose an inspection and replacement policy for a single component system that successively executes missions with random durations. The failure process of the system can be divided into two states, namely, normal and defective, following the delay time concept. Inspections are carried out periodically and immediately after the completion of each mission (random inspections). The failed state is always identified immediately, whereas the defective state can only be revealed by an inspection. If the system fails or is defective at a periodic inspection, then replacement is immediate. If, however, the system is defective at a random inspection, then replacement will be postponed if the time to the subsequent periodic inspection is shorter than a pre-determined threshold, and immediate otherwise. We derive the long run expected cost per unit time and then investigate the optimal periodic inspection interval and postponement threshold. A numerical example is presented to demonstrate the applicability of the proposed maintenance policy. - Highlights: • A delay time model of inspection is introduced for mission-based systems. • Periodic and random inspections are performed to check the state. • Replacement of the defective system at a random inspection can be postponed.

Expert system of real time for support of operators of atomic power plants

International Nuclear Information System (INIS)

Bashlykov, A.A.; Davidenko, N.N.; Dumshev, V.G.; Kislov, G.I.; Pavlova, E.V.; Prozorovskij, E.D.; Bashlykov, A.A.

1994-01-01

The problems of construction and introdution of an intellectual system for information support of operators at nuclear power plants are discussed. This system is used for operator assisstance during real time decision making for NPP operational regime control

An analysis of periodic solutions of bi-directional associative memory networks with time-varying delays

International Nuclear Information System (INIS)

Cao Jinde; Jiang Qiuhao

2004-01-01

In this Letter, several sufficient conditions are derived for the existence and uniqueness of periodic oscillatory solution for bi-directional associative memory (BAM) networks with time-varying delays by employing a new Lyapunov functional and an elementary inequality, and all other solutions of the BAM networks converge exponentially to the unique periodic solution. These criteria are presented in terms of system parameters and have important leading significance in the design and applications of periodic neural circuits for delayed BAM. As an illustration, two numerical examples are worked out using the results obtained

Fuzzy operation and real time surveillance of a nuclear reactor

International Nuclear Information System (INIS)

Si-Fodil, M.; Guely, F.; Siarry, P.; Tyran, J.L.

1997-01-01

The operating power of nuclear power plants needs to be modulated according to the thin evolutions of electric power demand. Two parameters are concerned by load following operations: the power axial disequilibrium and the position of control rods. This paper deals with the automation of the control of power axial disequilibrium using boration-dilution. An automatic system based on fuzzy logic is proposed which can be substituted to the expert operator who is in charge of this fastidious manual task. The management of water and boron flow rates are studied in details. A Graphic interface was designed for the real-time surveillance of the reactor. (J.S.)

Reply to 'Comment on 'Almost-periodic time observables for bound quantum systems''

International Nuclear Information System (INIS)

Hall, Michael J W

2009-01-01

In a recent paper (Hall 2008 J. Phys. A: Math. Gen. 41 255301), I made several critical remarks on a 'Hermitian time operator' proposed by Galapon (2002 Proc. R. Soc. A 458 2671). Galapon has correctly pointed out that remarks pertaining to 'denseness' of the commutator domain are wrong (Galapon 2008 J. Phys. A: Math. Theor. 42 018001). However, the other remarks still apply, and it is further noted that a given quantum system can be a member of this domain only at a set of times of total measure zero. (reply)

Real-Time Assessment and Diagnosis of Process Operating Performance

Directory of Open Access Journals (Sweden)

Shabnam Sedghi

2017-04-01

Full Text Available Over time, the performance of processes may deviate from the initial design due to process variations and uncertainties, making it necessary to develop systematic methods for online optimality assessment based on routine operating process data. Some processes have multiple operating modes caused by the set point change of the critical process variables to achieve different product specifications. On the other hand, the operating region in each operating mode can alter, due to uncertainties. In this paper, we will establish an optimality assessment framework for processes that typically have multi-mode, multi-region operations, as well as transitions between different modes. The kernel density approach for mode detection is adopted and improved for operating mode detection. For online mode detection, the model-based clustering discriminant analysis (MclustDA approach is incorporated with some a priori knowledge of the system. In addition, multi-modal behavior of steady-state modes is tackled utilizing the mixture probabilistic principal component regression (MPPCR method, and dynamic principal component regression (DPCR is used to investigate transitions between different modes. Moreover, a probabilistic causality detection method based on the sequential forward floating search (SFFS method is introduced for diagnosing poor or non-optimum behavior. Finally, the proposed method is tested on the Tennessee Eastman (TE benchmark simulation process in order to evaluate its performance.

The relative importance of real-time in-cab and external feedback in managing fatigue in real-world commercial transport operations.

Science.gov (United States)

Fitzharris, Michael; Liu, Sara; Stephens, Amanda N; Lenné, Michael G

2017-05-29

Real-time driver monitoring systems represent a solution to address key behavioral risks as they occur, particularly distraction and fatigue. The efficacy of these systems in real-world settings is largely unknown. This article has three objectives: (1) to document the incidence and duration of fatigue in real-world commercial truck-driving operations, (2) to determine the reduction, if any, in the incidence of fatigue episodes associated with providing feedback, and (3) to tease apart the relative contribution of in-cab warnings from 24/7 monitoring and feedback to employers. Data collected from a commercially available in-vehicle camera-based driver monitoring system installed in a commercial truck fleet operating in Australia were analyzed. The real-time driver monitoring system makes continuous assessments of driver drowsiness based on eyelid position and other factors. Data were collected in a baseline period where no feedback was provided to drivers. Real-time feedback to drivers then occurred via in-cab auditory and haptic warnings, which were further enhanced by direct feedback by company management when fatigue events were detected by external 24/7 monitors. Fatigue incidence rates and their timing of occurrence across the three time periods were compared. Relative to no feedback being provided to drivers when fatigue events were detected, in-cab warnings resulted in a 66% reduction in fatigue events, with a 95% reduction achieved by the real-time provision of direct feedback in addition to in-cab warnings (p safety culture of the company in terms of how the information is used. Data were analysed on a per-truck trip basis, and the findings are indicative of fatigue events in a large-scale commercial transport fleet. Future research ought to account for individual driver performance, which was not possible with the available data in this retrospective analysis. Evidence that real-time driver monitoring feedback is effective in reducing fatigue events is

Periodic fluctuations in correlation-based connectivity density time series: Application to wind speed-monitoring network in Switzerland

Science.gov (United States)

Laib, Mohamed; Telesca, Luciano; Kanevski, Mikhail

2018-02-01

In this paper, we study the periodic fluctuations of connectivity density time series of a wind speed-monitoring network in Switzerland. By using the correlogram-based robust periodogram annual periodic oscillations were found in the correlation-based network. The intensity of such annual periodic oscillations is larger for lower correlation thresholds and smaller for higher. The annual periodicity in the connectivity density seems reasonably consistent with the seasonal meteo-climatic cycle.

Integrated real-time information to use in commercial, logistics and operational activities provide by the national control center operation of Transpetro

Energy Technology Data Exchange (ETDEWEB)

Aniceto, Hello A. R. [National Control Center Operation Transpetro, Rio de Janeiro, (Brazil)

2010-07-01

TRANSPETRO needed real time computational tools to manage its commercial, logistics and operational activities more efficiently. TRANSPETRO's National Control Center Operation developed an information site that provides information in real time on the process plans involved in each operation, using a Plant Information Management System (PIMS). SCADA systems were introduced during 2009 and 2010. This paper reports on the global introduction of the site and its basic architecture. Every screen displays the overall data in real time on movement in volume in pipeline operated by TRANSPETRO. The products transported are tracked for each infrastructure and are shown on dynamic geographic maps. Applications have been developed to improve the quality of information available to customers. It was found that the development of this site using PIMS technology brought gains in support to decision-making at the strategic and tactical levels for TRANSPETRO.

Effects of combined linear and nonlinear periodic training on physical fitness and competition times in finswimmers.

Science.gov (United States)

Yu, Kyung-Hun; Suk, Min-Hwa; Kang, Shin-Woo; Shin, Yun-A

2014-10-01

The purpose of this study was to investigate the effect of combined linear and nonlinear periodic training on physical fitness and competition times in finswimmers. The linear resistance training model (6 days/week) and nonlinear underwater training (4 days/week) were applied to 12 finswimmers (age, 16.08± 1.44 yr; career, 3.78± 1.90 yr) for 12 weeks. Body composition measures included weight, body mass index (BMI), percent fat, and fat-free mass. Physical fitness measures included trunk flexion forward, trunk extension backward, sargent jump, 1-repetition-maximum (1 RM) squat, 1 RM dead lift, knee extension, knee flexion, trunk extension, trunk flexion, and competition times. Body composition and physical fitness were improved after the 12-week periodic training program. Weight, BMI, and percent fat were significantly decreased, and trunk flexion forward, trunk extension backward, sargent jump, 1 RM squat, 1 RM dead lift, and knee extension (right) were significantly increased. The 50- and 100-m times significantly decreased in all 12 athletes. After 12 weeks of training, all finswimmers who participated in this study improved their times in a public competition. These data indicate that combined linear and nonlinear periodic training enhanced the physical fitness and competition times in finswimmers.

The TileCal Online Energy Estimation for the Next LHC Operation Period

CERN Document Server

Peralva, B S; The ATLAS collaboration; Cerqueira, A S; Seixas, J M

2014-01-01

This work presents a study on the TileCal online energy estimation for the next LHC operation period (Run2). Due to hardware limitation, the algorithm that performs the online energy estimation must remain based on the linear and fast Optimal Filter (OF) technique, which envisages the use of the background covariance matrix in its design. During Run1, TileCal made use of an identity matrix to describe and the background covariance matrix, which showed to be a reasonable approximation for the low luminosity scenario. Under such conditions, the background for most of its cells comprised mainly electronic noise which can be approximated as a uncorrelated Gaussian process. However, as the pile-up introduces a non-Gaussian component to the background, the OF method presents larger variance and it becomes biased. The use of the background covariance matrix in the design of the OF weights is expected to improve the energy estimation performance. The results for the scenario considered show that for high occupancy ce...

Natural convection in square enclosure induced by inner circular cylinder with time-periodic pulsating temperature

KAUST Repository

Huang, Zhu

2015-03-01

The periodic unsteady natural convection flow and heat transfer in a square enclosure containing a concentric circular cylinder is numerically studied. The temperature of the inner circular cylinder fluctuates periodically with time at higher averaged value while the temperature of the enclosure keeps lower constant, and the natural convection is driven by the temperature difference. The two-dimensional natural convection is simulated with high accuracy temporal spectral method and local radial basis functions method. The Rayleigh number is studied in the range 103 ≤ Ra ≤ 106, the temperature pulsating period ranges from 0.01 to 100 and the temperature pulsating amplitudes are a = 0.5, 1.0 and 1.5. Numerical results reveal that the fluid flow and heat transfer is strongly dependent on the pulsating temperature of inner cylinder. Comparing with the steady state natural convection, the heat transfer is enhanced generally for the time-periodic unsteady natural convection, and the local maximum heat transfer rate is observed for Ra = 105 and 106. Moreover, the phenomenon of backward heat transfer is discussed quantitatively. Also, the influence of pulsating temperature on the unsteady fluid flow and heat transfer are discussed and analyzed.

Period-doubling bifurcation and chaos control in a discrete-time mosquito model

Directory of Open Access Journals (Sweden)

Qamar Din

2017-12-01

Full Text Available This article deals with the study of some qualitative properties of a discrete-time mosquito Model. It is shown that there exists period-doubling bifurcation for wide range of bifurcation parameter for the unique positive steady-state of given system. In order to control the bifurcation we introduced a feedback strategy. For further confirmation of complexity and chaotic behavior largest Lyapunov exponents are plotted.

Evaluating the efficiency of a zakat institution over a period of time using data envelopment analysis

Science.gov (United States)

Krishnan, Anath Rau; Hamzah, Ahmad Aizuddin

2017-08-01

It is crucial for a zakat institution to evaluate and understand how efficiently they have operated in the past, thus ideal strategies could be developed for future improvement. However, evaluating the efficiency of a zakat institution is actually a challenging process as it involves the presence of multiple inputs or/and outputs. This paper proposes a step-by-step procedure comprising two data envelopment analysis models, namely dual Charnes-Cooper-Rhodes and slack-based model to quantitatively measure the overall efficiency of a zakat institution over a period of time. The applicability of the proposed procedure was demonstrated by evaluating the efficiency of Pusat Zakat Sabah, Malaysia from the year of 2007 up to 2015 by treating each year as a decision making unit. Two inputs (i.e. number of staff and number of branches) and two outputs (i.e. total collection and total distribution) were used to measure the overall efficiency achieved each year. The causes of inefficiency and strategy for future improvement were discussed based on the results.

A computer-based time study system for timber harvesting operations

Science.gov (United States)

Jingxin Wang; Joe McNeel; John Baumgras

2003-01-01

A computer-based time study system was developed for timber harvesting operations. Object-oriented techniques were used to model and design the system. The front-end of the time study system resides on the MS Windows CE and the back-end is supported by MS Access. The system consists of three major components: a handheld system, data transfer interface, and data storage...

Primate enamel evinces long period biological timing and regulation of life history.

Science.gov (United States)

Bromage, Timothy G; Hogg, Russell T; Lacruz, Rodrigo S; Hou, Chen

2012-07-21

The factor(s) regulating the combination of traits that define the overall life history matrix of mammalian species, comprising attributes such as brain and body weight, age at sexual maturity, lifespan and others, remains a complete mystery. The principal objectives of the present research are (1) to provide evidence for a key variable effecting life history integration and (2) to provide a model for how one would go about investigating the metabolic mechanisms responsible for this rhythm. We suggest here that a biological rhythm with a period greater than the circadian rhythm is responsible for observed variation in primate life history. Evidence for this rhythm derives from studies of tooth enamel formation. Enamel contains an enigmatic periodicity in its microstructure called the striae of Retzius, which develops at species specific intervals in units of whole days. We refer to this enamel rhythm as the repeat interval (RI). For primates, we identify statistically significant relationships between RI and all common life history traits. Importantly, RI also correlates with basal and specific metabolic rates. With the exception of estrous cyclicity, all relationships share a dependence upon body mass. This dependence on body mass informs us that some aspect of metabolism is responsible for periodic energy allocations at RI timescales, regulating cell proliferation rates and growth, thus controlling the pace, patterning, and co-variation of life history traits. Estrous cyclicity relates to the long period rhythm in a body mass-independent manner. The mass-dependency and -independency of life history relationships with RI periodicity align with hypothalamic-mediated neurosecretory anterior and posterior pituitary outputs. We term this period the Havers-Halberg Oscillation (HHO), in reference to Clopton Havers, a 17th Century hard tissue anatomist, and Franz Halberg, a long-time explorer of long-period rhythms. We propose a mathematical model that may help elucidate

Optimization of an Operative Period at Radical Mastectomies

Directory of Open Access Journals (Sweden)

V. Yu. Vasilyev

2008-01-01

Full Text Available Blood loss volume is determined visually and approximately in most cases of surgical interventions, which most commonly leads to its underestimation, inadequate compensation, and development of hypovolemia. The latter induces peripheral vasospasm resulting in circulatory hypoxia, metabolic acidosis, diminished immunity, and worse reparative capacities of the body in the postoperative period. The transfused liquid volumes exceeding blood loss cause an increase in interstitial fluid volume, tissue edema and, hence, lead to impaired pulmonary gas exchange, enlarged postoperative wound edema, and postoperative complications. Administration of infusion media at a temperature lower than the body temperature has multiple adverse effects that impair the function of organs and systems. The typical response to hypothermia is peripheral vasospasm, followed by the development of circulatory hypoxia and metabolic acidosis. The objective of the study was to precisely estimate the volume of intraoperative blood loss and its adequate compensation and to correct central hemodynamic parameters and the body’s water sectors by nor-mothermal infusion therapy. Subjects and methods. The body’s water sectors, central hemodynamics, oxygen balance, and intraoperative blood loss volume were studied. Three groups of patients with radical mastectomy were comparatively analyzed. In Group 1 including 35 women operated on for breast cancer, the magnitude of blood loss was determined by eye and standard infusion therapy was performed, by using the mean solution temperatures of 20°C. Group 2 comprised 20 patients in whom blood loss was measured using a balance and infusion therapy was performed in accordance with the volume of the measured blood loss at the same temperature as in Group 1. Group 3 (n=18 received infusion therapy with the solutions warmed up to 37°C in accordance with blood loss volume determined applying a balance. Results. The studies have shown it

Optimal base-stock policy for the inventory system with periodic review, backorders and sequential lead times

DEFF Research Database (Denmark)

Johansen, Søren Glud; Thorstenson, Anders

2008-01-01

We extend well-known formulae for the optimal base stock of the inventory system with continuous review and constant lead time to the case with periodic review and stochastic, sequential lead times. Our extension uses the notion of the 'extended lead time'. The derived performance measures...

HANFORD SITE AIR OPERATING PERMIT SEMIANNUAL REPORT FOR THE PERIOD 07/01/2004 THRU 12/31/2004

International Nuclear Information System (INIS)

GREEN, W.E.

2005-01-01

The Hanford Site Air Operating Permit (AOP), Number 00-05-006, became effective on July 2, 2001. One condition contained in the AOP, ''Standard Terms and Conditions'', Section 4.3.3, is the requirement to submit semiannual reports by March 15th and September 15th each year, which are certified for truth, accuracy, and completeness by a Responsible Official. This semiannual report contains information from July 1, 2004 through December 31, 2004. Copies of semiannual reports are transmitted to the Washington State Department of Ecology (Ecology). the Washington State Department of Health (WDOH), the Benton Clean Air Authority (BCAA), and the US Environmental Protection Agency (EPA), Region 10. For the applicable reporting period, AOP, ''Standard Terms and Conditions'', Section 4.3.3, as amended in August 2002 and December 2002, identifies the following. (1) Each semiannual report will provide a reference to deviation reports submitted to the regulatory agencies as required by Section 4.5. ''Permit Deviation Reporting''. (2) Each semiannual report will consist of reports of any required monitoring not submitted previously to the agencies or a reference to reports of required monitoring submitted during the reporting period. (3) Each semiannual report will contain a summary of any substantiated air emission complaint investigation(s) required in Table 1.2 of AOP, Attachment 1, and issued during the reporting period. (4) For all minor radioactive emission points (potential to emit <0.1 mrem to the maximally exposed individual) listed in AOP, Attachment 2. Tables 1.2. 1.3, and 2.1, each semiannual report will confirm that any required monitoring was conducted to verify low emissions during the reporting period. Data derived from that monitoring will be reported in the Annual National Emission Standards for Hazardous Air Pollutants (NESHAP) Report (AOP, ''Standard Terms and Conditions'', Section 4.3.1). AOP requirement is for annual monitoring (e.g., four 1 week samples

A Systematic Approach for Real-Time Operator Functional State Assessment

Science.gov (United States)

Zhang, Guangfan; Wang, Wei; Pepe, Aaron; Xu, Roger; Schnell, Thomas; Anderson, Nick; Heitkamp, Dean; Li, Jiang; Li, Feng; McKenzie, Frederick

2012-01-01

A task overload condition often leads to high stress for an operator, causing performance degradation and possibly disastrous consequences. Just as dangerous, with automated flight systems, an operator may experience a task underload condition (during the en-route flight phase, for example), becoming easily bored and finding it difficult to maintain sustained attention. When an unexpected event occurs, either internal or external to the automated system, the disengaged operator may neglect, misunderstand, or respond slowly/inappropriately to the situation. In this paper, we discuss an approach for Operator Functional State (OFS) monitoring in a typical aviation environment. A systematic ground truth finding procedure has been designed based on subjective evaluations, performance measures, and strong physiological indicators. The derived OFS ground truth is continuous in time compared to a very sparse estimation of OFS based on an expert review or subjective evaluations. It can capture the variations of OFS during a mission to better guide through the training process of the OFS assessment model. Furthermore, an OFS assessment model framework based on advanced machine learning techniques was designed and the systematic approach was then verified and validated with experimental data collected in a high fidelity Boeing 737 simulator. Preliminary results show highly accurate engagement/disengagement detection making it suitable for real-time applications to assess pilot engagement.

Periodic Solution of Second-Order Hamiltonian Systems with a Change Sign Potential on Time Scales

Directory of Open Access Journals (Sweden)

You-Hui Su

2009-01-01

Full Text Available This paper is concerned with the second-order Hamiltonian system on time scales 𝕋 of the form uΔΔ(ρ(t+μb(t|u(t|μ−2u(t+∇¯H(t,u(t=0, Δ-a.e. t∈[0,T]𝕋 , u(0−u(T=uΔ(ρ(0−uΔ(ρ(T=0, where 0,T∈𝕋. By using the minimax methods in critical theory, an existence theorem of periodic solution for the above system is established. As an application, an example is given to illustrate the result. This is probably the first time the existence of periodic solutions for second-order Hamiltonian system on time scales has been studied by critical theory.

Novel criteria for global exponential periodicity and stability of recurrent neural networks with time-varying delays

International Nuclear Information System (INIS)

Song Qiankun

2008-01-01

In this paper, the global exponential periodicity and stability of recurrent neural networks with time-varying delays are investigated by applying the idea of vector Lyapunov function, M-matrix theory and inequality technique. We assume neither the global Lipschitz conditions on these activation functions nor the differentiability on these time-varying delays, which were needed in other papers. Several novel criteria are found to ascertain the existence, uniqueness and global exponential stability of periodic solution for recurrent neural network with time-varying delays. Moreover, the exponential convergence rate index is estimated, which depends on the system parameters. Some previous results are improved and generalized, and an example is given to show the effectiveness of our method

Spectral Analysis on Time-Course Expression Data: Detecting Periodic Genes Using a Real-Valued Iterative Adaptive Approach

Directory of Open Access Journals (Sweden)

Kwadwo S. Agyepong

2013-01-01

Full Text Available Time-course expression profiles and methods for spectrum analysis have been applied for detecting transcriptional periodicities, which are valuable patterns to unravel genes associated with cell cycle and circadian rhythm regulation. However, most of the proposed methods suffer from restrictions and large false positives to a certain extent. Additionally, in some experiments, arbitrarily irregular sampling times as well as the presence of high noise and small sample sizes make accurate detection a challenging task. A novel scheme for detecting periodicities in time-course expression data is proposed, in which a real-valued iterative adaptive approach (RIAA, originally proposed for signal processing, is applied for periodogram estimation. The inferred spectrum is then analyzed using Fisher’s hypothesis test. With a proper -value threshold, periodic genes can be detected. A periodic signal, two nonperiodic signals, and four sampling strategies were considered in the simulations, including both bursts and drops. In addition, two yeast real datasets were applied for validation. The simulations and real data analysis reveal that RIAA can perform competitively with the existing algorithms. The advantage of RIAA is manifested when the expression data are highly irregularly sampled, and when the number of cycles covered by the sampling time points is very reduced.

Effects of operator time pressure and noise on manual ultrasonic testing

International Nuclear Information System (INIS)

Enkvist, J.; Edland, A.; Svenson, O.

2002-01-01

In earlier studies of manual ultrasonic testing, great variations have been found in operator performance, often attributed to operator fatigue. However, no conclusive findings have been reported. In the present study, twenty operators performed manual ultrasonic inspections of six test-pieces with manufactured flaws. The operators performed the inspections under stress (high arousal - time pressure and noise) and no-stress conditions; one condition the first day and the other the second and last day. According to the Yerkes-Dodson Law there is an optimal arousal level where performance is highest. It was hypothesised that the stress condition led to a level of arousal so high that it would affect the results negatively. However, contrary to the hypotheses it was found that the manipulation increased operator performance. Operators with the stress condition day 1 performed better than the other operators (under the no-stress condition). This was interpreted as the 'stress first' (group 1) operators had established efficient performance patterns the first day - affecting also the second day. Operators beginning with stress condition also tended to be more motivated. It was concluded that operator performance is affected by arousal. (author)

Time-dependent reliability analysis of nuclear reactor operators using probabilistic network models

International Nuclear Information System (INIS)

Oka, Y.; Miyata, K.; Kodaira, H.; Murakami, S.; Kondo, S.; Togo, Y.

1987-01-01

Human factors are very important for the reliability of a nuclear power plant. Human behavior has essentially a time-dependent nature. The details of thinking and decision making processes are important for detailed analysis of human reliability. They have, however, not been well considered by the conventional methods of human reliability analysis. The present paper describes the models for the time-dependent and detailed human reliability analysis. Recovery by an operator is taken into account and two-operators models are also presented

Annual cycle solar energy utilization with seasonal storage. Part 8. Study on periodic steady state of the annual cycle energy system at a practical operation; Kisetsukan chikunetsu ni yoru nenkan cycle taiyo energy riyo system ni kansuru kenkyu. 8

Energy Technology Data Exchange (ETDEWEB)

Tanaka, H; Okumiya, M [Nagoya University, Nagoya (Japan)

1997-11-25

A study was made of the periodic steady state of the annual cycle solar energy system with seasonal heat storage at a practical operation. Cold heat in winter and warm heat in summer are stored in the seasonal storage tank, and these are each used in shift until when demand for cold/warm heat appears. Moreover, gap in quantity of cold/warm heat going in/out of the heat storage tank during a year is filled by natural energy such as solar energy, so that the system can be operated in annual cycles. Studies were conducted of the periodic unsteady term and the problem on lowering of performance during the term such as the periodic unsteady term of water temperature inside the seasonal heat storage tank and temperature of the soil around the storage tank, and the level of lowering of performance during the term, necessity of additional operation/control at the start of operation and aged deterioration of the system. Within the assumption, even if starting operation in any time of the year, the system could show the performance almost expected from the first operation year with no additional system operation and control required only at the start of operation. It is thought that the heat source selection control of heat pump largely contributes to this. 4 refs., 5 figs., 3 tabs.

Realization of a unique time evolution unitary operator in Klein Gordon theory

International Nuclear Information System (INIS)

Balasubramanian, T.S.; Bhatia, S.Kr.

1986-01-01

The scattering theory for the Klein Gordon equation, with time-dependent potential and in a non-static space-time, is considered. Using the Klein Gordon equation formulated in the Hilbert space L 2 (R 3 ) and the Einstein's relativistic equation in the space L 2 (R 3 ,dx) and establishing the equivalence of the vacuum states of their linearized forms in the Hilbert space L 2 (R 3 ) with the help of unique symmetric symplectic operator, the time evolution unitary operator U(t) has been fixed for the Klein Gordon eqution, incorporating either the positive or negative frequencies, in the infinite dimensional Hilbert space L 2 (R 3 ). (author)

Nonlinear perturbations of differential operators with nontrivial kernel and applications to third order periodic boundary value problems

International Nuclear Information System (INIS)

Afuwape, A.U.; Omari, P.

1987-11-01

This paper deals with the solvability of the nonlinear operator equations in normed spaces Lx=EGx+f, where L is a linear map with possible nontrivial kernel. Applications are given to the existence of periodic solutions for the third order scalar differential equation x'''+ax''+bx'+cx+g(t,x)=p(t), under various conditions on the interaction of g(t,x)/x with spectral configurations of a, b and c. (author). 48 refs

Nonlocal Operational Calculi for Dunkl Operators

Directory of Open Access Journals (Sweden)

Ivan H. Dimovski

2009-03-01

Full Text Available The one-dimensional Dunkl operator $D_k$ with a non-negative parameter $k$, is considered under an arbitrary nonlocal boundary value condition. The right inverse operator of $D_k$, satisfying this condition is studied. An operational calculus of Mikusinski type is developed. In the frames of this operational calculi an extension of the Heaviside algorithm for solution of nonlocal Cauchy boundary value problems for Dunkl functional-differential equations $P(D_ku = f$ with a given polynomial $P$ is proposed. The solution of these equations in mean-periodic functions reduces to such problems. Necessary and sufficient condition for existence of unique solution in mean-periodic functions is found.

Improved long-term outcomes after resection of pancreatic adenocarcinoma: a comparison between two time periods.