A variable-gain output feedback control design approach

NASA Technical Reports Server (NTRS)

Haylo, Nesim

1989-01-01

A multi-model design technique to find a variable-gain control law defined over the whole operating range is proposed. The design is formulated as an optimal control problem which minimizes a cost function weighing the performance at many operating points. The solution is obtained by embedding into the Multi-Configuration Control (MCC) problem, a multi-model robust control design technique. In contrast to conventional gain scheduling which uses a curve fit of single model designs, the optimal variable-gain control law stabilizes the plant at every operating point included in the design. An iterative algorithm to compute the optimal control gains is presented. The methodology has been successfully applied to reconfigurable aircraft flight control and to nonlinear flight control systems.

Vehicle dynamics control of four in-wheel motor drive electric vehicle using gain scheduling based on tyre cornering stiffness estimation

NASA Astrophysics Data System (ADS)

Xiong, Lu; Yu, Zhuoping; Wang, Yang; Yang, Chen; Meng, Yufeng

2012-06-01

This paper focuses on the vehicle dynamic control system for a four in-wheel motor drive electric vehicle, aiming at improving vehicle stability under critical driving conditions. The vehicle dynamics controller is composed of three modules, i.e. motion following control, control allocation and vehicle state estimation. Considering the strong nonlinearity of the tyres under critical driving conditions, the yaw motion of the vehicle is regulated by gain scheduling control based on the linear quadratic regulator theory. The feed-forward and feedback gains of the controller are updated in real-time by online estimation of the tyre cornering stiffness, so as to ensure the control robustness against environmental disturbances as well as parameter uncertainty. The control allocation module allocates the calculated generalised force requirements to each in-wheel motor based on quadratic programming theory while taking the tyre longitudinal/lateral force coupling characteristic into consideration. Simulations under a variety of driving conditions are carried out to verify the control algorithm. Simulation results indicate that the proposed vehicle stability controller can effectively stabilise the vehicle motion under critical driving conditions.

Gain-Scheduled Fault Tolerance Control Under False Identification

NASA Technical Reports Server (NTRS)

Shin, Jong-Yeob; Belcastro, Christine (Technical Monitor)

2006-01-01

An active fault tolerant control (FTC) law is generally sensitive to false identification since the control gain is reconfigured for fault occurrence. In the conventional FTC law design procedure, dynamic variations due to false identification are not considered. In this paper, an FTC synthesis method is developed in order to consider possible variations of closed-loop dynamics under false identification into the control design procedure. An active FTC synthesis problem is formulated into an LMI optimization problem to minimize the upper bound of the induced-L2 norm which can represent the worst-case performance degradation due to false identification. The developed synthesis method is applied for control of the longitudinal motions of FASER (Free-flying Airplane for Subscale Experimental Research). The designed FTC law of the airplane is simulated for pitch angle command tracking under a false identification case.

A variable-gain output feedback control design methodology

NASA Technical Reports Server (NTRS)

Halyo, Nesim; Moerder, Daniel D.; Broussard, John R.; Taylor, Deborah B.

1989-01-01

A digital control system design technique is developed in which the control system gain matrix varies with the plant operating point parameters. The design technique is obtained by formulating the problem as an optimal stochastic output feedback control law with variable gains. This approach provides a control theory framework within which the operating range of a control law can be significantly extended. Furthermore, the approach avoids the major shortcomings of the conventional gain-scheduling techniques. The optimal variable gain output feedback control problem is solved by embedding the Multi-Configuration Control (MCC) problem, previously solved at ICS. An algorithm to compute the optimal variable gain output feedback control gain matrices is developed. The algorithm is a modified version of the MCC algorithm improved so as to handle the large dimensionality which arises particularly in variable-gain control problems. The design methodology developed is applied to a reconfigurable aircraft control problem. A variable-gain output feedback control problem was formulated to design a flight control law for an AFTI F-16 aircraft which can automatically reconfigure its control strategy to accommodate failures in the horizontal tail control surface. Simulations of the closed-loop reconfigurable system show that the approach produces a control design which can accommodate such failures with relative ease. The technique can be applied to many other problems including sensor failure accommodation, mode switching control laws and super agility.

A model-based gain scheduling approach for controlling the common-rail system for GDI engines

NASA Astrophysics Data System (ADS)

di Gaeta, Alessandro; Montanaro, Umberto; Fiengo, Giovanni; Palladino, Angelo; Giglio, Veniero

2012-04-01

The progressive reduction in vehicle emission requirements have forced the automotive industry to invest in research for developing alternative and more efficient control strategies. All control features and resources are permanently active in an electronic control unit (ECU), ensuring the best performance with respect to emissions, fuel economy, driveability and diagnostics, independently from engine working point. In this article, a considerable step forward has been achieved by the common-rail technology which has made possible to vary the injection pressure over the entire engine speed range. As a consequence, the injection of a fixed amount of fuel is more precise and multiple injections in a combustion cycle can be made. In this article, a novel gain scheduling pressure controller for gasoline direct injection (GDI) engine is designed to stabilise the mean fuel pressure into the rail and to track demanded pressure trajectories. By exploiting a simple control-oriented model describing the mean pressure dynamics in the rail, the control structure turns to be simple enough to be effectively implemented in commercial ECUs. Experimental results in a wide range of operating points confirm the effectiveness of the proposed control method to tame efficiently the mean value pressure dynamics of the plant showing a good accuracy and robustness with respect to unavoidable parameters uncertainties, unmodelled dynamics, and hidden coupling terms.

Switching State-Feedback LPV Control with Uncertain Scheduling Parameters

NASA Technical Reports Server (NTRS)

He, Tianyi; Al-Jiboory, Ali Khudhair; Swei, Sean Shan-Min; Zhu, Guoming G.

2017-01-01

This paper presents a new method to design Robust Switching State-Feedback Gain-Scheduling (RSSFGS) controllers for Linear Parameter Varying (LPV) systems with uncertain scheduling parameters. The domain of scheduling parameters are divided into several overlapped subregions to undergo hysteresis switching among a family of simultaneously designed LPV controllers over the corresponding subregion with the guaranteed H-infinity performance. The synthesis conditions are given in terms of Parameterized Linear Matrix Inequalities that guarantee both stability and performance at each subregion and associated switching surfaces. The switching stability is ensured by descent parameter-dependent Lyapunov function on switching surfaces. By solving the optimization problem, RSSFGS controller can be obtained for each subregion. A numerical example is given to illustrate the effectiveness of the proposed approach over the non-switching controllers.

New LMI based gain-scheduling control for recovering contact-free operation of a magnetically levitated rotor

NASA Astrophysics Data System (ADS)

Wang, M.; Cole, M. O. T.; Keogh, P. S.

2017-11-01

A new approach for the recovery of contact-free levitation of a rotor supported by active magnetic bearings (AMB) is assessed through control strategy design, system modelling and experimental verification. The rotor is considered to make contact with a touchdown bearing (TDB), which may lead to entrapment in a bi-stable nonlinear response. A linear matrix inequality (LMI) based gain-scheduling H∞ control technique is introduced to recover the rotor to a contact-free state. The controller formulation involves a time-varying effective stiffness parameter, which can be evaluated in terms of forces transmitted through the TDB. Rather than measuring these forces directly, an observer is introduced with a model of the base structure to transform base acceleration signals using polytopic coordinates for controller adjustment. Force transmission to the supporting base structure will occur either through an AMB alone without contact, or through the AMB and TDB with contact and this must be accounted for in the observer design. The controller is verified experimentally in terms of (a) non-contact robust stability and vibration suppression performance; (b) control action for contact-free recovery at typical running speeds with various unbalance and TDB misalignment conditions; and (c) coast-down experimental tests. The results demonstrate the effectiveness of the AMB control action whenever it operates within its dynamic load capacity.

Optimal PID gain schedule for hydrogenerators

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

Orelind, G.; Wozniak, L.; Medanic, J.

1989-09-01

This paper describes the development and testing of a digital gain switching governor for hydrogenerators. Optimal gains were found at different load points by minimizing a quadratic performance criterion prior to controller operating. During operation, the gain sets are switched in depending on the gate position and speed error magnitude. With gain switching operating, the digital governor was shown to have a substantial reduction of noise on the command signal and up to 42% faster responses to power requests. Non-linear control strategies enabled the digital governor to have a 2.5% to 2% reduction in speed overshoot on startups, and anmore » 8% to 1% reduction in undershoot on load rejections as compared to the analog.« less

Alternative Methods to Standby Gain Scheduling Following Air Data System Failure

DTIC Science & Technology

2009-09-01

in the event of air data system failures. There are two problems with this current method. First, the pilot must take time away from other ...pertinent tasks to manually position the standby-gains via the landing gear handle, air-to-air refueling door switch or some other means. Second, the...the way, the original airspeed estimator was improved and two other alternatives to standby-gain-scheduling were investigated. Knowing what

Scheduling algorithms for automatic control systems for technological processes

NASA Astrophysics Data System (ADS)

Chernigovskiy, A. S.; Tsarev, R. Yu; Kapulin, D. V.

2017-01-01

Wide use of automatic process control systems and the usage of high-performance systems containing a number of computers (processors) give opportunities for creation of high-quality and fast production that increases competitiveness of an enterprise. Exact and fast calculations, control computation, and processing of the big data arrays - all of this requires the high level of productivity and, at the same time, minimum time of data handling and result receiving. In order to reach the best time, it is necessary not only to use computing resources optimally, but also to design and develop the software so that time gain will be maximal. For this purpose task (jobs or operations), scheduling techniques for the multi-machine/multiprocessor systems are applied. Some of basic task scheduling methods for the multi-machine process control systems are considered in this paper, their advantages and disadvantages come to light, and also some usage considerations, in case of the software for automatic process control systems developing, are made.

77 FR 64848 - Proposed Collection; Comment Request for Form 1120S, Schedule D, Schedule K-1, and Schedule M-3

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-23

... 1120S, Schedule D, Schedule K-1, and Schedule M-3 AGENCY: Internal Revenue Service (IRS), Treasury... (Loss) Reconciliation for S Corporations With Total Assets of $10 Million or More, and Schedule K-1... Corporation, Schedule D (Form 1120S), Capital Gains and Losses and Built-in Gains, Schedule K-1 (Form 1120S...

Asthma Triggers: Gain Control

MedlinePlus

... Centers Asthma Contact Us Share Asthma Triggers: Gain Control Breathing Freely: Controlling Asthma Triggers This video features ... Air Quality: Biological Pollutants Help Your Child Gain Control Over Asthma Top of Page Molds About Molds ...

Gain scheduled linear quadratic control for quadcopter

NASA Astrophysics Data System (ADS)

Okasha, M.; Shah, J.; Fauzi, W.; Hanouf, Z.

2017-12-01

This study exploits the dynamics and control of quadcopters using Linear Quadratic Regulator (LQR) control approach. The quadcopter’s mathematical model is derived using the Newton-Euler method. It is a highly manoeuvrable, nonlinear, coupled with six degrees of freedom (DOF) model, which includes aerodynamics and detailed gyroscopic moments that are often ignored in many literatures. The linearized model is obtained and characterized by the heading angle (i.e. yaw angle) of the quadcopter. The adopted control approach utilizes LQR method to track several reference trajectories including circle and helix curves with significant variation in the yaw angle. The controller is modified to overcome difficulties related to the continuous changes in the operating points and eliminate chattering and discontinuity that is observed in the control input signal. Numerical non-linear simulations are performed using MATLAB and Simulink to illustrate to accuracy and effectiveness of the proposed controller.

Optimal Scheduling Method of Controllable Loads in DC Smart Apartment Building

NASA Astrophysics Data System (ADS)

Shimoji, Tsubasa; Tahara, Hayato; Matayoshi, Hidehito; Yona, Atsushi; Senjyu, Tomonobu

2015-12-01

From the perspective of global warming suppression and the depletion of energy resources, renewable energies, such as the solar collector (SC) and photovoltaic generation (PV), have been gaining attention in worldwide. Houses or buildings with PV and heat pumps (HPs) are recently being used in residential areas widely due to the time of use (TOU) electricity pricing scheme which is essentially inexpensive during middle-night and expensive during day-time. If fixed batteries and electric vehicles (EVs) can be introduced in the premises, the electricity cost would be even more reduced. While, if the occupants arbitrarily use these controllable loads respectively, power demand in residential buildings may fluctuate in the future. Thus, an optimal operation of controllable loads such as HPs, batteries and EV should be scheduled in the buildings in order to prevent power flow from fluctuating rapidly. This paper proposes an optimal scheduling method of controllable loads, and the purpose is not only the minimization of electricity cost for the consumers, but also suppression of fluctuation of power flow on the power supply side. Furthermore, a novel electricity pricing scheme is also suggested in this paper.

Quantized Synchronization of Chaotic Neural Networks With Scheduled Output Feedback Control.

PubMed

Wan, Ying; Cao, Jinde; Wen, Guanghui

In this paper, the synchronization problem of master-slave chaotic neural networks with remote sensors, quantization process, and communication time delays is investigated. The information communication channel between the master chaotic neural network and slave chaotic neural network consists of several remote sensors, with each sensor able to access only partial knowledge of output information of the master neural network. At each sampling instants, each sensor updates its own measurement and only one sensor is scheduled to transmit its latest information to the controller's side in order to update the control inputs for the slave neural network. Thus, such communication process and control strategy are much more energy-saving comparing with the traditional point-to-point scheme. Sufficient conditions for output feedback control gain matrix, allowable length of sampling intervals, and upper bound of network-induced delays are derived to ensure the quantized synchronization of master-slave chaotic neural networks. Lastly, Chua's circuit system and 4-D Hopfield neural network are simulated to validate the effectiveness of the main results.In this paper, the synchronization problem of master-slave chaotic neural networks with remote sensors, quantization process, and communication time delays is investigated. The information communication channel between the master chaotic neural network and slave chaotic neural network consists of several remote sensors, with each sensor able to access only partial knowledge of output information of the master neural network. At each sampling instants, each sensor updates its own measurement and only one sensor is scheduled to transmit its latest information to the controller's side in order to update the control inputs for the slave neural network. Thus, such communication process and control strategy are much more energy-saving comparing with the traditional point-to-point scheme. Sufficient conditions for output feedback control

Application of precomputed control laws in a reconfigurable aircraft flight control system

NASA Technical Reports Server (NTRS)

Moerder, Daniel D.; Halyo, Nesim; Broussard, John R.; Caglayan, Alper K.

1989-01-01

A self-repairing flight control system concept in which the control law is reconfigured after actuator and/or control surface damage to preserve stability and pilot command tracking is described. A key feature of the controller is reconfigurable multivariable feedback. The feedback gains are designed off-line and scheduled as a function of the aircraft control impairment status so that reconfiguration is performed simply by updating the gain schedule after detection of an impairment. A novel aspect of the gain schedule design procedure is that the schedule is calculated using a linear quadratic optimization-based simultaneous stabilization algorithm in which the scheduled gain is constrained to stabilize a collection of plant models representing the aircraft in various control failure modes. A description and numerical evaluation of a controller design for a model of a statically unstable high-performance aircraft are given.

Optimization of control gain by operator adjustment

NASA Technical Reports Server (NTRS)

Kruse, W.; Rothbauer, G.

1973-01-01

An optimal gain was established by measuring errors at 5 discrete control gain settings in an experimental set-up consisting of a 2-dimensional, first-order pursuit tracking task performed by subjects (S's). No significant experience effect on optimum gain setting was found in the first experiment. During the second experiment, in which control gain was continuously adjustable, high experienced S's tended to reach the previously determined optimum gain quite accurately and quickly. Less experienced S's tended to select a marginally optimum gain either below or above the experimentally determined optimum depending on initial control gain setting, although mean settings of both groups were equal. This quick and simple method is recommended for selecting control gains for different control systems and forcing functions.

Schedule of controlled substances; placement of fospropofol into schedule IV. Final rule.

PubMed

2009-10-06

With the issuance of this final rule, the Deputy Administrator of the Drug Enforcement Administration (DEA) places the substance fospropofol, including its salts, isomers and salts of isomers whenever the existence of such salts, isomers, and salts of isomers is possible, into schedule IV of the Controlled Substances Act (CSA). As a result of this rule, the regulatory controls and criminal sanctions of schedule IV will be applicable to the manufacture, distribution, dispensing, importation, and exportation of fospropofol and products containing fospropofol.

77 FR 63766 - Schedules of Controlled Substances: Placement of Methylone Into Schedule I

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-17

... DEPARTMENT OF JUSTICE Drug Enforcement Administration 21 CFR Part 1308 [Docket No. DEA-357] Schedules of Controlled Substances: Placement of Methylone Into Schedule I AGENCY: Drug Enforcement Administration, Department of Justice. ACTION: Notice of proposed rulemaking. SUMMARY: The Drug Enforcement...

Gain-Scheduled Complementary Filter Design for a MEMS Based Attitude and Heading Reference System

PubMed Central

Yoo, Tae Suk; Hong, Sung Kyung; Yoon, Hyok Min; Park, Sungsu

2011-01-01

This paper describes a robust and simple algorithm for an attitude and heading reference system (AHRS) based on low-cost MEMS inertial and magnetic sensors. The proposed approach relies on a gain-scheduled complementary filter, augmented by an acceleration-based switching architecture to yield robust performance, even when the vehicle is subject to strong accelerations. Experimental results are provided for a road captive test during which the vehicle dynamics are in high-acceleration mode and the performance of the proposed filter is evaluated against the output from a conventional linear complementary filter. PMID:22163824

Expert system for on-board satellite scheduling and control

NASA Technical Reports Server (NTRS)

Barry, John M.; Sary, Charisse

1988-01-01

An Expert System is described which Rockwell Satellite and Space Electronics Division (S&SED) is developing to dynamically schedule the allocation of on-board satellite resources and activities. This expert system is the Satellite Controller. The resources to be scheduled include power, propellant and recording tape. The activities controlled include scheduling satellite functions such as sensor checkout and operation. The scheduling of these resources and activities is presently a labor intensive and time consuming ground operations task. Developing a schedule requires extensive knowledge of the system and subsystems operations, operational constraints, and satellite design and configuration. This scheduling process requires highly trained experts anywhere from several hours to several weeks to accomplish. The process is done through brute force, that is examining cryptic mnemonic data off line to interpret the health and status of the satellite. Then schedules are formulated either as the result of practical operator experience or heuristics - that is rules of thumb. Orbital operations must become more productive in the future to reduce life cycle costs and decrease dependence on ground control. This reduction is required to increase autonomy and survivability of future systems. The design of future satellites require that the scheduling function be transferred from ground to on board systems.

19 CFR 162.45a - Summary forfeiture of Schedule I and Schedule II controlled substances.

Code of Federal Regulations, 2010 CFR

2010-04-01

... OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) INSPECTION, SEARCH, AND SEIZURE....S.C. 965. Accordingly, in the case of a seizure of Schedule I or Schedule II controlled substances...

Cross-Layer Adaptive Feedback Scheduling of Wireless Control Systems

PubMed Central

Xia, Feng; Ma, Longhua; Peng, Chen; Sun, Youxian; Dong, Jinxiang

2008-01-01

There is a trend towards using wireless technologies in networked control systems. However, the adverse properties of the radio channels make it difficult to design and implement control systems in wireless environments. To attack the uncertainty in available communication resources in wireless control systems closed over WLAN, a cross-layer adaptive feedback scheduling (CLAFS) scheme is developed, which takes advantage of the co-design of control and wireless communications. By exploiting cross-layer design, CLAFS adjusts the sampling periods of control systems at the application layer based on information about deadline miss ratio and transmission rate from the physical layer. Within the framework of feedback scheduling, the control performance is maximized through controlling the deadline miss ratio. Key design parameters of the feedback scheduler are adapted to dynamic changes in the channel condition. An event-driven invocation mechanism for the feedback scheduler is also developed. Simulation results show that the proposed approach is efficient in dealing with channel capacity variations and noise interference, thus providing an enabling technology for control over WLAN. PMID:27879934

Young Children's Affective Decision-Making in a Gambling Task: Does Difficulty in Learning the Gain/Loss Schedule Matter?

ERIC Educational Resources Information Center

Gao, Shan; Wei, Yonggang; Bai, Junjie; Lin, Chongde; Li, Hong

2009-01-01

This research investigated the development of affective decision-making (ADM) during early childhood, in particular role of difficulty in learning a gain/loss schedule. In Experiment 1, we administrated the Children's Gambling Task (CGT) to 60 Chinese children aged 3 and 4, replicating the results obtained by Kerr and Zelazo [Kerr, A., & Zelazo,…

Variable gain for a wind turbine pitch control

NASA Technical Reports Server (NTRS)

Seidel, R. C.; Birchenough, A. G.

1981-01-01

The gain variation is made in the software logic of the pitch angle controller. The gain level is changed depending upon the level of power error. The control uses low gain for low pitch activity the majority of the time. If the power exceeds ten percent offset above rated, the gain is increased to a higher gain to more effectively limit power. A variable gain control functioned well in tests on the Mod-0 wind turbine.

Controlling gain one photon at a time

PubMed Central

Schwartz, Gregory W; Rieke, Fred

2013-01-01

Adaptation is a salient property of sensory processing. All adaptational or gain control mechanisms face the challenge of obtaining a reliable estimate of the property of the input to be adapted to and obtaining this estimate sufficiently rapidly to be useful. Here, we explore how the primate retina balances the need to change gain rapidly and reliably when photons arrive rarely at individual rod photoreceptors. We find that the weakest backgrounds that decrease the gain of the retinal output signals are similar to those that increase human behavioral threshold, and identify a novel site of gain control in the retinal circuitry. Thus, surprisingly, the gain of retinal signals begins to decrease essentially as soon as background lights are detectable; under these conditions, gain control does not rely on a highly averaged estimate of the photon count, but instead signals from individual photon absorptions trigger changes in gain. DOI: http://dx.doi.org/10.7554/eLife.00467.001 PMID:23682314

Schedules of Controlled Substances: Extension of Temporary Placement of Three Synthetic Phenethylamines in Schedule I. Final order.

PubMed

2015-11-13

The Administrator of the Drug Enforcement Administration is issuing this final order extending the temporary schedule I status for three synthetic phenethylamines into the Controlled Substances Act pursuant to the temporary scheduling provisions of the Act. The substances are: 2-(4-iodo-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethanamine (25I-NBOMe; 2C-I-NBOMe; 25I; Cimbi-5), 2-(4-chloro-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethanamine (25C-NBOMe; 2C-C-NBOMe; 25C; Cimbi-82), and 2-(4-bromo-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethanamine (25B-NBOMe; 2C-B-NBOMe; 25B; Cimbi-36) [hereinafter 25I-NBOMe, 2C-NBOMe, and 25-NBOMe, respectively]. The initial temporary scheduling was based on a finding by the Deputy Administrator that the placement of these synthetic phenethylamines and their optical, positional, and geometric isomers, salts, and salts of isomers into schedule I of the Controlled Substances Act is necessary to avoid an imminent hazard to the public safety. The current final order temporarily placing 25I-NBOMe, 25C-NBOMe, and 25B-NBOMe in schedule I is due to expire on November 14, 2015. This final order will extend the temporary scheduling of 25I-NBOMe, 25C-NBOMe, and 25B-NBOMe for one year, or until the permanent scheduling action for these three substances is completed, whichever occurs first. As a result of this order, the full effect of the Controlled Substances Act and its implementing regulations, including criminal, civil and administrative penalties, sanctions, and regulatory controls of schedule I substances will be imposed on the manufacture, distribution, possession, importation, and exportation of these synthetic phenethylamines.

Schedules of controlled substances: placement of 5-methoxy-N,N-dimethyltryptamine into Schedule I of the Controlled Substances Act. Final rule.

PubMed

2010-12-20

With the issuance of this final rule, the Deputy Administrator of the Drug Enforcement Administration (DEA) places the substance 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT), including its salts, isomers and salts of isomers whenever the existence of such salts, isomers, and salts of isomers is possible, into schedule I of the Controlled Substances Act (CSA). This action by the DEA Deputy Administrator is based on a scheduling recommendation from the Assistant Secretary for Health of the Department of Health and Human Services (DHHS) and a DEA review indicating that 5-MeO-DMT meets the criteria for placement in schedule I of the CSA. This final rule will impose the criminal sanctions and regulatory controls of schedule I substances under the CSA on the manufacture, distribution, dispensing, importation, exportation, and possession of 5-MeO-DMT.

Schedules of controlled substances: temporary placement of three synthetic cannabinoids into Schedule I. Final order.

PubMed

2013-05-16

The Deputy Administrator of the Drug Enforcement Administration (DEA) is issuing this final order to temporarily schedule three synthetic cannabinoids under the Controlled Substances Act (CSA) pursuant to the temporary scheduling provisions of 21 U.S.C. 811(h). The substances are (1-pentyl-1H-indol-3-yl)(2,2,3,3-tetramethylcyclopropyl)methanone (UR-144), [1-(5-fluoro-pentyl)-1H-indol-3-yl](2,2,3,3-tetramethylcyclopropyl)methanone (5-fluoro-UR-144, XLR11) and N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (APINACA, AKB48). This action is based on a finding by the Deputy Administrator that the placement of these synthetic cannabinoids and their salts, isomers and salts of isomers into Schedule I of the CSA is necessary to avoid an imminent hazard to the public safety. As a result of this order, the full effect of the CSA and the Controlled Substances Import and Export Act (CSIEA) and their implementing regulations including criminal, civil and administrative penalties, sanctions and regulatory controls of Schedule I substances will be imposed on the manufacture, distribution, possession, importation, and exportation of these synthetic cannabinoids.

Schedules of Controlled Substances: Placement of Three Synthetic Phenethylamines Into Schedule I. Final rule.

PubMed

2016-09-27

With the issuance of this final rule, the Administrator of the Drug Enforcement Administration places three synthetic phenethylamines: 2-(4-iodo-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethanamine (25I-NBOMe; 2C-I-NBOMe; 25I; Cimbi-5), 2-(4-chloro-2,5-dimethoxyphenyl)-N- (2-methoxybenzyl)ethanamine (25C-NBOMe; 2C-C-NBOMe; 25C; Cimbi-82), and 2-(4-bromo-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethanamine (25B- NBOMe; 2C-B-NBOMe; 25B; Cimbi-36), including their optical, positional, and geometric isomers, salts and salts of isomers, whenever the existence of such salts, isomers, and salts of isomers is possible, into schedule I of the Controlled Substances Act. This scheduling action is pursuant to the Controlled Substances Act which requires that such actions be made on the record after opportunity for a hearing through formal rulemaking. This action continues the application of the regulatory controls and administrative, civil, and criminal sanctions applicable to schedule I controlled substances on persons who handle (manufacture, distribute, reverse distribute, import, export, engage in research, conduct instructional activities or chemical analysis, or possess), or propose to handle 25I-NBOMe, 25C-NBOMe, or 25B-NBOMe.

Decision-theoretic control of EUVE telescope scheduling

NASA Technical Reports Server (NTRS)

Hansson, Othar; Mayer, Andrew

1993-01-01

This paper describes a decision theoretic scheduler (DTS) designed to employ state-of-the-art probabilistic inference technology to speed the search for efficient solutions to constraint-satisfaction problems. Our approach involves assessing the performance of heuristic control strategies that are normally hard-coded into scheduling systems and using probabilistic inference to aggregate this information in light of the features of a given problem. The Bayesian Problem-Solver (BPS) introduced a similar approach to solving single agent and adversarial graph search patterns yielding orders-of-magnitude improvement over traditional techniques. Initial efforts suggest that similar improvements will be realizable when applied to typical constraint-satisfaction scheduling problems.

Contrast Gain Control in Auditory Cortex

PubMed Central

Rabinowitz, Neil C.; Willmore, Ben D.B.; Schnupp, Jan W.H.; King, Andrew J.

2011-01-01

Summary The auditory system must represent sounds with a wide range of statistical properties. One important property is the spectrotemporal contrast in the acoustic environment: the variation in sound pressure in each frequency band, relative to the mean pressure. We show that neurons in ferret auditory cortex rescale their gain to partially compensate for the spectrotemporal contrast of recent stimulation. When contrast is low, neurons increase their gain, becoming more sensitive to small changes in the stimulus, although the effectiveness of contrast gain control is reduced at low mean levels. Gain is primarily determined by contrast near each neuron's preferred frequency, but there is also a contribution from contrast in more distant frequency bands. Neural responses are modulated by contrast over timescales of ∼100 ms. By using contrast gain control to expand or compress the representation of its inputs, the auditory system may be seeking an efficient coding of natural sounds. PMID:21689603

Schedules of controlled substances: temporary placement of three synthetic phenethylamines into Schedule I. Final order.

PubMed

2013-11-15

The Deputy Administrator of the Drug Enforcement Administration (DEA) is issuing this final order to temporarily schedule three synthetic phenethylamines into the Controlled Substances Act (CSA) pursuant to the temporary scheduling provisions of 21 U.S.C. 811(h). The substances are 2-(4-iodo-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethanamine (25I-NBOMe; 2C-I-NBOMe; 25I; Cimbi-5), 2-(4-chloro-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethanamine (25C-NBOMe; 2C-C-NBOMe; 25C; Cimbi-82), and 2-(4-bromo-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethanamine (25B-NBOMe; 2C-B-NBOMe; 25B; Cimbi-36) [hereinafter 25I-NBOMe, 25C-NBOMe, and 25B-NBOMe]. This action is based on a finding by the Deputy Administrator that the placement of these synthetic phenethylamines and their optical, positional, and geometric isomers, salts and salts of isomers in schedule I of the CSA is necessary to avoid an imminent hazard to the public safety. As a result of this order, the regulatory controls and administrative, civil, and criminal sanctions applicable to schedule I controlled substances will be imposed on persons who handle (manufacture, distribute, dispense, import, export, engage in research, conduct instructional activities, and possess), or propose to handle these synthetic phenethylamines.

Compensated gain control circuit for buck regulator command charge circuit

DOEpatents

Barrett, David M.

1996-01-01

A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit.

Compensated gain control circuit for buck regulator command charge circuit

DOEpatents

Barrett, D.M.

1996-11-05

A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit. 5 figs.

78 FR 26701 - Schedules of Controlled Substances: Placement of Lorcaserin Into Schedule IV

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-08

... 1321. Under the CSA, controlled substances are classified in one of five schedules based upon their... is based on a recommendation from the Assistant Secretary of HHS and on an evaluation of all other... indicated support for controlling lorcaserin under the CSA based on the abuse potential of the substance...

77 FR 64032 - Schedules of Controlled Substances: Extension of Temporary Placement of Methylone Into Schedule I...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-18

... is possible, will remain in effect until April 20, 2013, or until rulemaking proceedings are... isomers is possible, into Schedule I of the Controlled Substances Act (CSA). The temporary scheduling of... to the public safety pursuant to 21 U.S.C. 811(h)(1). At the time the Final Order took effect...

A human factors approach to range scheduling for satellite control

NASA Technical Reports Server (NTRS)

Wright, Cameron H. G.; Aitken, Donald J.

1991-01-01

Range scheduling for satellite control presents a classical problem: supervisory control of a large-scale dynamic system, with unwieldy amounts of interrelated data used as inputs to the decision process. Increased automation of the task, with the appropriate human-computer interface, is highly desirable. The development and user evaluation of a semi-automated network range scheduling system is described. The system incorporates a synergistic human-computer interface consisting of a large screen color display, voice input/output, a 'sonic pen' pointing device, a touchscreen color CRT, and a standard keyboard. From a human factors standpoint, this development represents the first major improvement in almost 30 years to the satellite control network scheduling task.

Instructional versus schedule control of humans' choices in situations of diminishing returns

PubMed Central

Hackenberg, Timothy D.; Joker, Veronica R.

1994-01-01

Four adult humans chose repeatedly between a fixed-time schedule (of points later exchangeable for money) and a progressive-time schedule that began at 0 s and increased by a fixed number of seconds with each point delivered by that schedule. Each point delivered by the fixed-time schedule reset the requirements of the progressive-time schedule to its minimum value. Subjects were provided with instructions that specified a particular sequence of choices. Under the initial conditions, the instructions accurately specified the optimal choice sequence. Thus, control by instructions and optimal control by the programmed contingencies both supported the same performance. To distinguish the effects of instructions from schedule sensitivity, the correspondence between the instructed and optimal choice patterns was gradually altered across conditions by varying the step size of the progressive-time schedule while maintaining the same instructions. Step size was manipulated, typically in 1-s units, first in an ascending and then in a descending sequence of conditions. Instructions quickly established control in all 4 subjects but, by narrowing the range of choice patterns, they reduced subsequent sensitivity to schedule changes. Instructional control was maintained across the ascending sequence of progressive-time values for each subject, but eventually diminished, giving way to more schedule-appropriate patterns. The transition from instruction-appropriate to schedule-appropriate behavior was characterized by an increase in the variability of choice patterns and local increases in point density. On the descending sequence of progressive-time values, behavior appeared to be schedule sensitive, sometimes even optimally sensitive, but it did not always change systematically with the contingencies, suggesting the involvement of other factors. PMID:16812747

Planning, scheduling, and control for automatic telescopes

NASA Technical Reports Server (NTRS)

Drummond, Mark; Swanson, Keith; Philips, Andy; Levinson, Rich; Bresina, John

1992-01-01

This paper presents an argument for the appropriateness of Entropy Reduction Engine (ERE) technology to the planning, scheduling, and control components of Automatic Photoelectric Telescope (APT) management. The paper is organized as follows. In the next section, we give a brief summary of the planning and scheduling requirements for APTs. Following this, in section 3, we give an ERE project precis, couched primarily in terms of project objectives. Section 4 gives a sketch of the match-up between problem and technology, and section 5 outlines where we want to go with this work.

An assessment of PERT as a technique for schedule planning and control

NASA Technical Reports Server (NTRS)

Sibbers, C. W.

1982-01-01

The PERT technique including the types of reports which can be computer generated using the NASA/LaRC PPARS System is described. An assessment is made of the effectiveness of PERT on various types of efforts as well as for specific purposes, namely, schedule planning, schedule analysis, schedule control, monitoring contractor schedule performance, and management reporting. This assessment is based primarily on the author's knowledge of the usage of PERT by NASA/LaRC personnel since the early 1960's. Both strengths and weaknesses of the technique for various applications are discussed. It is intended to serve as a reference guide for personnel performing project planning and control functions and technical personnel whose responsibilities either include schedule planning and control or require a general knowledge of the subject.

76 FR 2287 - Schedules of Controlled Substances: Temporary Placement of Five Synthetic Cannabinoids Into...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-13

...] Schedules of Controlled Substances: Temporary Placement of Five Synthetic Cannabinoids Into Schedule I... Notice of Intent announcing its intention to temporarily place five synthetic cannabinoids into Schedule... announced its intention to temporarily place five synthetic cannabinoids into schedule I of the Controlled...

75 FR 79296 - Schedules of Controlled Substances: Placement of 5-Methoxy-N,N-Dimethyltryptamine into Schedule I...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-20

...] Schedules of Controlled Substances: Placement of 5-Methoxy-N,N- Dimethyltryptamine into Schedule I of the... Administration (DEA) places the substance 5- methoxy-N,N-dimethyltryptamine (5-MeO-DMT), including its salts..., actual abuse, pattern of abuse, and the relative potential for abuse of 5-methoxy-N,N-dimethyltryptamine...

Performance analysis of a large-grain dataflow scheduling paradigm

NASA Technical Reports Server (NTRS)

Young, Steven D.; Wills, Robert W.

1993-01-01

A paradigm for scheduling computations on a network of multiprocessors using large-grain data flow scheduling at run time is described and analyzed. The computations to be scheduled must follow a static flow graph, while the schedule itself will be dynamic (i.e., determined at run time). Many applications characterized by static flow exist, and they include real-time control and digital signal processing. With the advent of computer-aided software engineering (CASE) tools for capturing software designs in dataflow-like structures, macro-dataflow scheduling becomes increasingly attractive, if not necessary. For parallel implementations, using the macro-dataflow method allows the scheduling to be insulated from the application designer and enables the maximum utilization of available resources. Further, by allowing multitasking, processor utilizations can approach 100 percent while they maintain maximum speedup. Extensive simulation studies are performed on 4-, 8-, and 16-processor architectures that reflect the effects of communication delays, scheduling delays, algorithm class, and multitasking on performance and speedup gains.

Serotonin Affects Movement Gain Control in the Spinal Cord

PubMed Central

Glaser, Joshua I.; Deng, Linna; Thompson, Christopher K.; Stevenson, Ian H.; Wang, Qining; Hornby, Thomas George; Heckman, Charles J.; Kording, Konrad P.

2014-01-01

A fundamental challenge for the nervous system is to encode signals spanning many orders of magnitude with neurons of limited bandwidth. To meet this challenge, perceptual systems use gain control. However, whether the motor system uses an analogous mechanism is essentially unknown. Neuromodulators, such as serotonin, are prime candidates for gain control signals during force production. Serotonergic neurons project diffusely to motor pools, and, therefore, force production by one muscle should change the gain of others. Here we present behavioral and pharmaceutical evidence that serotonin modulates the input–output gain of motoneurons in humans. By selectively changing the efficacy of serotonin with drugs, we systematically modulated the amplitude of spinal reflexes. More importantly, force production in different limbs interacts systematically, as predicted by a spinal gain control mechanism. Psychophysics and pharmacology suggest that the motor system adopts gain control mechanisms, and serotonin is a primary driver for their implementation in force production. PMID:25232107

Loop gain stabilizing with an all-digital automatic-gain-control method for high-precision fiber-optic gyroscope.

PubMed

Zheng, Yue; Zhang, Chunxi; Li, Lijing; Song, Lailiang; Chen, Wen

2016-06-10

For a fiber-optic gyroscope (FOG) using electronic dithers to suppress the dead zone, without a fixed loop gain, the deterministic compensation for the dither signals in the control loop of the FOG cannot remain accurate, resulting in the dither residuals in the FOG rotation rate output and the navigation errors in the inertial navigation system. An all-digital automatic-gain-control method for stabilizing the loop gain of the FOG is proposed. By using a perturbation square wave to measure the loop gain of the FOG and adding an automatic gain control loop in the conventional control loop of the FOG, we successfully obtain the actual loop gain and make the loop gain converge to the reference value. The experimental results show that in the case of 20% variation in the loop gain, the dither residuals are successfully eliminated and the standard deviation of the FOG sampling outputs is decreased from 2.00  deg/h to 0.62  deg/h (sampling period 2.5 ms, 10 points smoothing). With this method, the loop gain of the FOG can be stabilized over the operation temperature range and in the long-time application, which provides a solid foundation for the engineering applications of the high-precision FOG.

Effects of internal gain assumptions in building energy calculations

NASA Astrophysics Data System (ADS)

Christensen, C.; Perkins, R.

1981-01-01

The utilization of direct solar gains in buildings can be affected by operating profiles, such as schedules for internal gains, thermostat controls, and ventilation rates. Building energy analysis methods use various assumptions about these profiles. The effects of typical internal gain assumptions in energy calculations are described. Heating and cooling loads from simulations using the DOE 2.1 computer code are compared for various internal gain inputs: typical hourly profiles, constant average profiles, and zero gain profiles. Prototype single-family-detached and multifamily-attached residential units are studied with various levels of insulation and infiltration. Small detached commercial buildings and attached zones in large commercial buildings are studied with various levels of internal gains. The results indicate that calculations of annual heating and cooling loads are sensitive to internal gains, but in most cases are relatively insensitive to hourly variations in internal gains.

Finding Optimal Gains In Linear-Quadratic Control Problems

NASA Technical Reports Server (NTRS)

Milman, Mark H.; Scheid, Robert E., Jr.

1990-01-01

Analytical method based on Volterra factorization leads to new approximations for optimal control gains in finite-time linear-quadratic control problem of system having infinite number of dimensions. Circumvents need to analyze and solve Riccati equations and provides more transparent connection between dynamics of system and optimal gain.

Schedules of Controlled Substances: Placement of UR-144, XLR11, and AKB48 into Schedule I. Final rule.

PubMed

2016-05-11

With the issuance of this final rule, the Drug Enforcement Administration places (1-pentyl-1H-indol-3-yl)(2,2,3,3-tetramethylcyclopropyl)methanone (UR-144), [1-(5-fluoro-pentyl)-1H-indol-3-yl](2,2,3,3-tetramethylcyclopropyl)methanone (5-fluoro-UR-144, XLR11), and N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (APINACA, AKB48), including their salts, isomers, and salts of isomers whenever the existence of such salts, isomers, and salts of isomers is possible, into schedule I of the Controlled Substances Act. This scheduling action is pursuant to the Controlled Substances Act which requires that such actions be made on the record after opportunity for a hearing through formal rulemaking. This action imposes the regulatory controls and administrative, civil, and criminal sanctions applicable to schedule I controlled substances on persons who handle (manufacture, distribute, reverse distribute, import, export, engage in research, conduct instructional activities or chemical analysis, or possess), or propose to handle UR-144, XLR11, or AKB48.

78 FR 21858 - Schedules of Controlled Substances: Temporary Placement of Three Synthetic Cannabinoids Into...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-12

...] Schedules of Controlled Substances: Temporary Placement of Three Synthetic Cannabinoids Into Schedule I... temporarily schedule three synthetic cannabinoids into the Controlled Substances Act (CSA) pursuant to the...). This action is based on a finding by the Deputy Administrator that the placement of these synthetic...

Commutated automatic gain control system

NASA Technical Reports Server (NTRS)

Yost, S. R.

1982-01-01

The commutated automatic gain control (AGC) system was designed and built for the prototype Loran-C receiver is discussed. The current version of the prototype receiver, the Mini L-80, was tested initially in 1980. The receiver uses a super jolt microcomputer to control a memory aided phase loop (MAPLL). The microcomputer also controls the input/output, latitude/longitude conversion, and the recently added AGC system. The AGC control adjusts the level of each station signal, such that the early portion of each envelope rise is about at the same amplitude in the receiver envelope detector.

Robust Optimal Adaptive Control Method with Large Adaptive Gain

NASA Technical Reports Server (NTRS)

Nguyen, Nhan T.

2009-01-01

In the presence of large uncertainties, a control system needs to be able to adapt rapidly to regain performance. Fast adaptation is referred to the implementation of adaptive control with a large adaptive gain to reduce the tracking error rapidly. However, a large adaptive gain can lead to high-frequency oscillations which can adversely affect robustness of an adaptive control law. A new adaptive control modification is presented that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. The modification is based on the minimization of the Y2 norm of the tracking error, which is formulated as an optimal control problem. The optimality condition is used to derive the modification using the gradient method. The optimal control modification results in a stable adaptation and allows a large adaptive gain to be used for better tracking while providing sufficient stability robustness. Simulations were conducted for a damaged generic transport aircraft with both standard adaptive control and the adaptive optimal control modification technique. The results demonstrate the effectiveness of the proposed modification in tracking a reference model while maintaining a sufficient time delay margin.

CARMENES instrument control system and operational scheduler

NASA Astrophysics Data System (ADS)

Garcia-Piquer, Alvaro; Guàrdia, Josep; Colomé, Josep; Ribas, Ignasi; Gesa, Lluis; Morales, Juan Carlos; Pérez-Calpena, Ana; Seifert, Walter; Quirrenbach, Andreas; Amado, Pedro J.; Caballero, José A.; Reiners, Ansgar

2014-07-01

The main goal of the CARMENES instrument is to perform high-accuracy measurements of stellar radial velocities (1m/s) with long-term stability. CARMENES will be installed in 2015 at the 3.5 m telescope in the Calar Alto Observatory (Spain) and it will be equipped with two spectrographs covering from the visible to the near-infrared. It will make use of its near-IR capabilities to observe late-type stars, whose peak of the spectral energy distribution falls in the relevant wavelength interval. The technology needed to develop this instrument represents a challenge at all levels. We present two software packages that play a key role in the control layer for an efficient operation of the instrument: the Instrument Control System (ICS) and the Operational Scheduler. The coordination and management of CARMENES is handled by the ICS, which is responsible for carrying out the operations of the different subsystems providing a tool to operate the instrument in an integrated manner from low to high user interaction level. The ICS interacts with the following subsystems: the near-IR and visible channels, composed by the detectors and exposure meters; the calibration units; the environment sensors; the front-end electronics; the acquisition and guiding module; the interfaces with telescope and dome; and, finally, the software subsystems for operational scheduling of tasks, data processing, and data archiving. We describe the ICS software design, which implements the CARMENES operational design and is planned to be integrated in the instrument by the end of 2014. The CARMENES operational scheduler is the second key element in the control layer described in this contribution. It is the main actor in the translation of the survey strategy into a detailed schedule for the achievement of the optimization goals. The scheduler is based on Artificial Intelligence techniques and computes the survey planning by combining the static constraints that are known a priori (i.e., target

Nonreciprocal gain control for ring laser

NASA Technical Reports Server (NTRS)

Dueker, G.; Lee, P.

1967-01-01

Nonreciprocal gain control is used in a ring laser where the two contracirculating beams may have differing intensities because of the residual Faraday rotation and other secondary nonreciprocal effects.

Is There a Downside to Schedule Control for the Work-Family Interface?

ERIC Educational Resources Information Center

Schieman, Scott; Young, Marisa

2010-01-01

Using data from a 2007 U.S. survey of workers, this article examines the implications of schedule control for work-family role blurring and work-family conflict. Four main findings indicate that (a) schedule control is associated with more frequent working at home and work-family multitasking activities; (b) the positive association between…

Automatic Gain Control in Compact Spectrometers.

PubMed

Protopopov, Vladimir

2016-03-01

An image intensifier installed in the optical path of a compact spectrometer may act not only as a fast gating unit, which is widely used for time-resolved measurements, but also as a variable attenuator-amplifier in a continuous wave mode. This opens the possibility of an automatic gain control, a new feature in spectroscopy. With it, the user is relieved from the necessity to manually adjust signal level at a certain value that it is done automatically by means of an electronic feedback loop. It is even more important that automatic gain control is done without changing exposure time, which is an additional benefit in time-resolved experiments. The concept, algorithm, design considerations, and experimental results are presented. © The Author(s) 2016.

Analysis of Issues for Project Scheduling by Multiple, Dispersed Schedulers (distributed Scheduling) and Requirements for Manual Protocols and Computer-based Support

NASA Technical Reports Server (NTRS)

Richards, Stephen F.

1991-01-01

Although computerized operations have significant gains realized in many areas, one area, scheduling, has enjoyed few benefits from automation. The traditional methods of industrial engineering and operations research have not proven robust enough to handle the complexities associated with the scheduling of realistic problems. To address this need, NASA has developed the computer-aided scheduling system (COMPASS), a sophisticated, interactive scheduling tool that is in wide-spread use within NASA and the contractor community. Therefore, COMPASS provides no explicit support for the large class of problems in which several people, perhaps at various locations, build separate schedules that share a common pool of resources. This research examines the issue of distributing scheduling, as applied to application domains characterized by the partial ordering of tasks, limited resources, and time restrictions. The focus of this research is on identifying issues related to distributed scheduling, locating applicable problem domains within NASA, and suggesting areas for ongoing research. The issues that this research identifies are goals, rescheduling requirements, database support, the need for communication and coordination among individual schedulers, the potential for expert system support for scheduling, and the possibility of integrating artificially intelligent schedulers into a network of human schedulers.

Intelligent Planning and Scheduling for Controlled Life Support Systems

NASA Technical Reports Server (NTRS)

Leon, V. Jorge

1996-01-01

Planning in Controlled Ecological Life Support Systems (CELSS) requires special look ahead capabilities due to the complex and long-term dynamic behavior of biological systems. This project characterizes the behavior of CELSS, identifies the requirements of intelligent planning systems for CELSS, proposes the decomposition of the planning task into short-term and long-term planning, and studies the crop scheduling problem as an initial approach to long-term planning. CELSS is studied in the realm of Chaos. The amount of biomass in the system is modeled using a bounded quadratic iterator. The results suggests that closed ecological systems can exhibit periodic behavior when imposed external or artificial control. The main characteristics of CELSS from the planning and scheduling perspective are discussed and requirements for planning systems are given. Crop scheduling problem is identified as an important component of the required long-term lookahead capabilities of a CELSS planner. The main characteristics of crop scheduling are described and a model is proposed to represent the problem. A surrogate measure of the probability of survival is developed. The measure reflects the absolute deviation of the vital reservoir levels from their nominal values. The solution space is generated using a probability distribution which captures both knowledge about the system and the current state of affairs at each decision epoch. This probability distribution is used in the context of an evolution paradigm. The concepts developed serve as the basis for the development of a simple crop scheduling tool which is used to demonstrate its usefulness in the design and operation of CELSS.

Commutated automatic gain control system

NASA Technical Reports Server (NTRS)

Yost, S. R.

1982-01-01

A commutated automatic gain control (AGC) system was designed and built for a prototype Loran C receiver. The receiver uses a microcomputer to control a memory aided phase-locked loop (MAPLL). The microcomputer also controls the input/output, latitude/longitude conversion, and the recently added AGC system. The circuit designed for the AGC is described, and bench and flight test results are presented. The AGC circuit described actually samples starting at a point 40 microseconds after a zero crossing determined by the software lock pulse ultimately generated by a 30 microsecond delay and add network in the receiver front end envelope detector.

Rethinking the Clockwork of Work: Why Schedule Control May Pay Off at Work and at Home.

PubMed

Kelly, Erin L; Moen, Phyllis

2007-11-01

Many employees face work-life conflicts and time deficits that negatively affect their health, well-being, effectiveness on the job, and organizational commitment. Many organizations have adopted flexible work arrangements but not all of them increase schedule control, that is, employees' control over when, where, and how much they work. This article describes some limitations of flexible work policies, proposes a conceptual model of how schedule control impacts work-life conflicts, and describes specific ways to increase employees' schedule control, including best practices for implementing common flexible work policies and Best Buy's innovative approach to creating a culture of schedule control.

Surveying air traffic control specialist perception of scheduling regulations

NASA Astrophysics Data System (ADS)

Thompson, Darrius E.

While there have been several studies conducted on air traffic controller fatigue, there is a lack of research on the subject since the scheduling policy changes that took place in 2012. The effectiveness of these changes has yet to be measured. The goal of this study was to investigate air traffic control specialist views towards the number of hours scheduled between shifts, changes in perception since 2012 regulation changes, and external factors that impact fatigue. A total of 54 FAA air traffic control specialist completed an online questionnaire. The results from the survey showed that the majority of respondents felt the 2012 regulation changes were not sufficient to address fatigue issues, and work with some amount sleep deprivation. The factors that appeared to have the most significant effect on fatigue included facility level, age group, availability of recuperative breaks, and children under 18 in the home.

Contrast gain control in first- and second-order motion perception.

PubMed

Lu, Z L; Sperling, G

1996-12-01

A novel pedestal-plus-test paradigm is used to determine the nonlinear gain-control properties of the first-order (luminance) and the second-order (texture-contrast) motion systems, that is, how these systems' responses to motion stimuli are reduced by pedestals and other masking stimuli. Motion-direction thresholds were measured for test stimuli consisting of drifting luminance and texture-contrast-modulation stimuli superimposed on pedestals of various amplitudes. (A pedestal is a static sine-wave grating of the same type and same spatial frequency as the moving test grating.) It was found that first-order motion-direction thresholds are unaffected by small pedestals, but at pedestal contrasts above 1-2% (5-10 x pedestal threshold), motion thresholds increase proportionally to pedestal amplitude (a Weber law). For first-order stimuli, pedestal masking is specific to the spatial frequency of the test. On the other hand, motion-direction thresholds for texture-contrast stimuli are independent of pedestal amplitude (no gain control whatever) throughout the accessible pedestal amplitude range (from 0 to 40%). However, when baseline carrier contrast increases (with constant pedestal modulation amplitude), motion thresholds increase, showing that gain control in second-order motion is determined not by the modulator (as in first-order motion) but by the carrier. Note that baseline contrast of the carrier is inherently independent of spatial frequency of the modulator. The drastically different gain-control properties of the two motion systems and prior observations of motion masking and motion saturation are all encompassed in a functional theory. The stimulus inputs to both first- and second-order motion process are normalized by feedforward, shunting gain control. The different properties arise because the modulator is used to control the first-order gain and the carrier is used to control the second-order gain.

Real-time control systems: feedback, scheduling and robustness

NASA Astrophysics Data System (ADS)

Simon, Daniel; Seuret, Alexandre; Sename, Olivier

2017-08-01

The efficient control of real-time distributed systems, where continuous components are governed through digital devices and communication networks, needs a careful examination of the constraints arising from the different involved domains inside co-design approaches. Thanks to the robustness of feedback control, both new control methodologies and slackened real-time scheduling schemes are proposed beyond the frontiers between these traditionally separated fields. A methodology to design robust aperiodic controllers is provided, where the sampling interval is considered as a control variable of the system. Promising experimental results are provided to show the feasibility and robustness of the approach.

Rethinking the Clockwork of Work: Why Schedule Control May Pay Off at Work and at Home

PubMed Central

Kelly, Erin L.; Moen, Phyllis

2014-01-01

The problem and the solution Many employees face work–life conflicts and time deficits that negatively affect their health, well-being, effectiveness on the job, and organizational commitment. Many organizations have adopted flexible work arrangements but not all of them increase schedule control, that is, employees’ control over when, where, and how much they work. This article describes some limitations of flexible work policies, proposes a conceptual model of how schedule control impacts work–life conflicts, and describes specific ways to increase employees’ schedule control, including best practices for implementing common flexible work policies and Best Buy’s innovative approach to creating a culture of schedule control. PMID:25598711

Contrast gain control: a bilinear model for chromatic selectivity.

PubMed

Singer, B; D'Zmura, M

1995-04-01

We report the results of psychophysical experiments on color contrast induction. In earlier work [Vision Res. 34, 3111 (1994)], we showed that modulating the spatial contrast of an annulus in time induces an apparent modulation of the contrast of a central disk, at isoluminance. Here we vary the chromatic properties of disk and annulus systematically in a study of the interactions among the luminance and the color-opponent channels. Results show that induced contrast depends linearly on both disk and annulus contrast, at low and moderate contrast levels. This dependence leads us to propose a bilinear model for color contrast gain control. The model predicts the magnitude and the chromatic properties of induced contrast. In agreement with experimental results, the model displays chromatic selectivity in contrast gain control and a negligible effect of contrast modulation at isoluminance on the appearance of achromatic contrast. We show that the bilinear model for chromatic selectivity may be realized as a feed-forward multiplicative gain control. Data collected at high contrast levels are fit by embellishing the model with saturating nonlinearities in the contrast gain control of each color channel.

Efficient operation scheduling for adsorption chillers using predictive optimization-based control methods

NASA Astrophysics Data System (ADS)

Bürger, Adrian; Sawant, Parantapa; Bohlayer, Markus; Altmann-Dieses, Angelika; Braun, Marco; Diehl, Moritz

2017-10-01

Within this work, the benefits of using predictive control methods for the operation of Adsorption Cooling Machines (ACMs) are shown on a simulation study. Since the internal control decisions of series-manufactured ACMs often cannot be influenced, the work focuses on optimized scheduling of an ACM considering its internal functioning as well as forecasts for load and driving energy occurrence. For illustration, an assumed solar thermal climate system is introduced and a system model suitable for use within gradient-based optimization methods is developed. The results of a system simulation using a conventional scheme for ACM scheduling are compared to the results of a predictive, optimization-based scheduling approach for the same exemplary scenario of load and driving energy occurrence. The benefits of the latter approach are shown and future actions for application of these methods for system control are addressed.

Schedules of Controlled Substances: Temporary Placement of Six Synthetic Cannabinoids (5F-ADB, 5F-AMB, 5F-APINACA, ADB-FUBINACA, MDMB-CHMICA and MDMB-FUBINACA) into Schedule I. Temporary Scheduling Order.

PubMed

2017-04-10

The Administrator of the Drug Enforcement Administration is issuing this temporary scheduling order to schedule six synthetic cannabinoids: methyl 2-(1-(5-fluoropentyl)-1H-indazole-3-carboxamido)-3,3-dimethylbutanoate [5F-ADB; 5F-MDMB-PINACA]; methyl 2-(1-(5-fluoropentyl)-1H-indazole-3-carboxamido)-3-methylbutanoate [5F-AMB]; N-(adamantan-1-yl)-1-(5-fluoropentyl)-1H-indazole-3-carboxamide [5F-APINACA, 5F-AKB48]; N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)-1-(4-fluorobenzyl)-1H-indazole-3-carboxamide [ADB-FUBINACA]; methyl 2-(1-(cyclohexylmethyl)-1H-indole-3-carboxamido)-3,3-dimethylbutanoate [MDMB-CHMICA, MMB-CHMINACA] and methyl 2-(1-(4-fluorobenzyl)-1H-indazole-3-carboxamido)-3,3-dimethylbutanoate [MDMB-FUBINACA], and their optical, positional, and geometric isomers, salts, and salts of isomers into schedule I pursuant to the temporary scheduling provisions of the Controlled Substances Act. This action is based on a finding by the Administrator that the placement of these synthetic cannabinoids into schedule I of the Controlled Substances Act is necessary to avoid an imminent hazard to the public safety. As a result of this order, the regulatory controls and administrative, civil, and criminal sanctions applicable to schedule I controlled substances will be imposed on persons who handle (manufacture, distribute, reverse distribute, import, export, engage in research, conduct instructional activities or chemical analysis, or possess), or propose to handle, 5F-ADB, 5F-AMB, 5F-APINACA, ADB-FUBINACA, MDMB-CHMICA or MDMB-FUBINACA.

Dynamics of cochlear nonlinearity: Automatic gain control or instantaneous damping?

PubMed

Altoè, Alessandro; Charaziak, Karolina K; Shera, Christopher A

2017-12-01

Measurements of basilar-membrane (BM) motion show that the compressive nonlinearity of cochlear mechanical responses is not an instantaneous phenomenon. For this reason, the cochlear amplifier has been thought to incorporate an automatic gain control (AGC) mechanism characterized by a finite reaction time. This paper studies the effect of instantaneous nonlinear damping on the responses of oscillatory systems. The principal results are that (i) instantaneous nonlinear damping produces a noninstantaneous gain control that differs markedly from typical AGC strategies; (ii) the kinetics of compressive nonlinearity implied by the finite reaction time of an AGC system appear inconsistent with the nonlinear dynamics measured on the gerbil basilar membrane; and (iii) conversely, those nonlinear dynamics can be reproduced using an harmonic oscillator with instantaneous nonlinear damping. Furthermore, existing cochlear models that include instantaneous gain-control mechanisms capture the principal kinetics of BM nonlinearity. Thus, an AGC system with finite reaction time appears neither necessary nor sufficient to explain nonlinear gain control in the cochlea.

The entropy reduction engine: Integrating planning, scheduling, and control

NASA Technical Reports Server (NTRS)

Drummond, Mark; Bresina, John L.; Kedar, Smadar T.

1991-01-01

The Entropy Reduction Engine, an architecture for the integration of planning, scheduling, and control, is described. The architecture is motivated, presented, and analyzed in terms of its different components; namely, problem reduction, temporal projection, and situated control rule execution. Experience with this architecture has motivated the recent integration of learning. The learning methods are described along with their impact on architecture performance.

Deadlock-free genetic scheduling algorithm for automated manufacturing systems based on deadlock control policy.

PubMed

Xing, KeYi; Han, LiBin; Zhou, MengChu; Wang, Feng

2012-06-01

Deadlock-free control and scheduling are vital for optimizing the performance of automated manufacturing systems (AMSs) with shared resources and route flexibility. Based on the Petri net models of AMSs, this paper embeds the optimal deadlock avoidance policy into the genetic algorithm and develops a novel deadlock-free genetic scheduling algorithm for AMSs. A possible solution of the scheduling problem is coded as a chromosome representation that is a permutation with repetition of parts. By using the one-step look-ahead method in the optimal deadlock control policy, the feasibility of a chromosome is checked, and infeasible chromosomes are amended into feasible ones, which can be easily decoded into a feasible deadlock-free schedule. The chromosome representation and polynomial complexity of checking and amending procedures together support the cooperative aspect of genetic search for scheduling problems strongly.

Scheduling and Delivering Aircraft to Departure Fixes in the NY Metroplex with Controller-Managed Spacing Tools

NASA Technical Reports Server (NTRS)

Chevalley, Eric; Parke, Bonny; Kraut, Josh M.; Bienert, Nancy; Omar, Faisal; Palmer, Everett A.

2015-01-01

In this paper, successful Time-Based Flow Management (TBFM) scheduling systems for arrivals are considered and adapted to apply to departures. We present a concept of operations that integrates Controller-Managed Spacing tools for departures (CMS-D) with existing tactical departure scheduling tools to coordinate demand at departure fixes in a metroplex environment. We tested our concept in a Human-in-the-Loop simulation and compared the effect of two scheduling conditions: 1) "Departure Scheduling" consisting of an emulation of the Integrated Departure and Arrival Capability (IDAC) where Towers and a Planner (Traffic Management Coordinator at the appropriate facility) coordinate aircraft scheduled takeoff times to departure fixes; and 2) "Arrival Sensitive Departure Scheduling" where, in addition, the Tower and Planner also consider arrival Scheduled Time of Arrivals (STAs) at the airport's dependent runway. Results indicate little difference between the two scheduling conditions, but a large difference between the No Tools and the two scheduling conditions with CMS-D tools. The scheduling/CMS-D tools conditions markedly reduced heading, speed clearances, and workload for controllers who were merging flows at the departure fixes. In the tool conditions, departure controllers conditioned departures earlier rather than later when aircraft were tied near the departure fixes. In the scheduling/CMS-D tools conditions, departures crossed the departure fixes 50 seconds earlier and with an 8% error rate (consisting of time ahead or behind desired time of arrival) compared to a 19% error rate in the No Tool condition. Two exploratory runs showed that similar beneficial effects can be obtained only with the CMS-D tools without scheduling takeoff times, but at the cost of a somewhat higher workload for controllers, indicating the benefits of pre-departure scheduling of aircraft with minimal delays. Hence, we found that CMS-D tools were very beneficial in the metroplex

Wave scheduling - Decentralized scheduling of task forces in multicomputers

NASA Technical Reports Server (NTRS)

Van Tilborg, A. M.; Wittie, L. D.

1984-01-01

Decentralized operating systems that control large multicomputers need techniques to schedule competing parallel programs called task forces. Wave scheduling is a probabilistic technique that uses a hierarchical distributed virtual machine to schedule task forces by recursively subdividing and issuing wavefront-like commands to processing elements capable of executing individual tasks. Wave scheduling is highly resistant to processing element failures because it uses many distributed schedulers that dynamically assign scheduling responsibilities among themselves. The scheduling technique is trivially extensible as more processing elements join the host multicomputer. A simple model of scheduling cost is used by every scheduler node to distribute scheduling activity and minimize wasted processing capacity by using perceived workload to vary decentralized scheduling rules. At low to moderate levels of network activity, wave scheduling is only slightly less efficient than a central scheduler in its ability to direct processing elements to accomplish useful work.

Contrast Gain Control Model Fits Masking Data

NASA Technical Reports Server (NTRS)

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

1994-01-01

We studied the fit of a contrast gain control model to data of Foley (JOSA 1994), consisting of thresholds for a Gabor patch masked by gratings of various orientations, or by compounds of two orientations. Our general model includes models of Foley and Teo & Heeger (IEEE 1994). Our specific model used a bank of Gabor filters with octave bandwidths at 8 orientations. Excitatory and inhibitory nonlinearities were power functions with exponents of 2.4 and 2. Inhibitory pooling was broad in orientation, but narrow in spatial frequency and space. Minkowski pooling used an exponent of 4. All of the data for observer KMF were well fit by the model. We have developed a contrast gain control model that fits masking data. Unlike Foley's, our model accepts images as inputs. Unlike Teo & Heeger's, our model did not require multiple channels for different dynamic ranges.

The Dynamic Planner: The Sequencer, Scheduler, and Runway Allocator for Air Traffic Control Automation

NASA Technical Reports Server (NTRS)

Wong, Gregory L.; Denery, Dallas (Technical Monitor)

2000-01-01

The Dynamic Planner (DP) has been designed, implemented, and integrated into the Center-TRACON Automation System (CTAS) to assist Traffic Management Coordinators (TMCs), in real time, with the task of planning and scheduling arrival traffic approximately 35 to 200 nautical miles from the destination airport. The TMC may input to the DP a series of current and future scheduling constraints that reflect the operation and environmental conditions of the airspace. Under these constraints, the DP uses flight plans, track updates, and Estimated Time of Arrival (ETA) predictions to calculate optimal runway assignments and arrival schedules that help ensure an orderly, efficient, and conflict-free flow of traffic into the terminal area. These runway assignments and schedules can be shown directly to controllers or they can be used by other CTAS tools to generate advisories to the controllers. Additionally, the TMC and controllers may override the decisions made by the DP for tactical considerations. The DP will adapt to computations to accommodate these manual inputs.

Gaining and sustaining schistosomiasis control: study protocol and baseline data prior to different treatment strategies in five African countries.

PubMed

Ezeamama, Amara E; He, Chun-La; Shen, Ye; Yin, Xiao-Ping; Binder, Sue C; Campbell, Carl H; Rathbun, Stephen; Whalen, Christopher C; N'Goran, Eliézer K; Utzinger, Jürg; Olsen, Annette; Magnussen, Pascal; Kinung'hi, Safari; Fenwick, Alan; Phillips, Anna; Ferro, Josefo; Karanja, Diana M S; Mwinzi, Pauline N M; Montgomery, Susan; Secor, W Evan; Hamidou, Amina; Garba, Amadou; King, Charles H; Colley, Daniel G

2016-05-26

The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was established in 2008 to answer strategic questions about schistosomiasis control. For programme managers, a high-priority question is: what are the most cost-effective strategies for delivering preventive chemotherapy (PCT) with praziquantel (PZQ)? This paper describes the process SCORE used to transform this question into a harmonized research protocol, the study design for answering this question, the village eligibility assessments and data resulting from the first year of the study. Beginning in 2009, SCORE held a series of meetings to specify empirical questions and design studies related to different schedules of PCT for schistosomiasis control in communities with high (gaining control studies) and moderate (sustaining control studies) prevalence of Schistosoma infection among school-aged children. Seven studies are currently being implemented in five African countries. During the first year, villages were screened for eligibility, and data were collected on prevalence and intensity of infection prior to randomisation and the implementation of different schemes of PZQ intervention strategies. These studies of different treatment schedules with PZQ will provide the most comprehensive data thus far on the optimal frequency and continuity of PCT for schistosomiasis infection and morbidity control. We expect that the study outcomes will provide data for decision-making for country programme managers and a rich resource of information to the schistosomiasis research community. The trials are registered at International Standard Randomised Controlled Trial registry (identifiers: ISRCTN99401114 , ISRCTN14849830 , ISRCTN16755535 , ISRCTN14117624 , ISRCTN95819193 and ISRCTN32045736 ).

Schedules of controlled substances: extension of temporary placement of UR-144, XLR11, and AKB48 in schedule I of the Controlled Substances Act. Final order.

PubMed

2015-05-15

The Administrator of the Drug Enforcement Administration (DEA) is issuing this final order to extend the temporary placement of (1-pentyl-1H-indol-3-yl)(2,2,3,3-tetramethylcyclopropyl)methanone (UR-144), [1-(5-fluoro-pentyl)-1H-indol-3-yl](2,2,3,3-tetramethylcyclopropyl)methanone (5-fluoro-UR-144, XLR11) and N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (APINACA, AKB48), including their salts, isomers, and salts of isomers whenever the existence of such salts, isomers, and salts of isomers is possible, in schedule I of the Controlled Substances Act. The current final order temporarily placing UR-144, XLR11, and AKB48 in schedule I is due to expire on May 15, 2015. This final order will extend the temporary scheduling of UR-144, XLR11, and AKB48 to May 15, 2016, or until the permanent scheduling action for these three substances is completed, whichever occurs first.

Hearing in noisy environments: noise invariance and contrast gain control

PubMed Central

Willmore, Ben D B; Cooke, James E; King, Andrew J

2014-01-01

Contrast gain control has recently been identified as a fundamental property of the auditory system. Electrophysiological recordings in ferrets have shown that neurons continuously adjust their gain (their sensitivity to change in sound level) in response to the contrast of sounds that are heard. At the level of the auditory cortex, these gain changes partly compensate for changes in sound contrast. This means that sounds which are structurally similar, but have different contrasts, have similar neuronal representations in the auditory cortex. As a result, the cortical representation is relatively invariant to stimulus contrast and robust to the presence of noise in the stimulus. In the inferior colliculus (an important subcortical auditory structure), gain changes are less reliably compensatory, suggesting that contrast- and noise-invariant representations are constructed gradually as one ascends the auditory pathway. In addition to noise invariance, contrast gain control provides a variety of computational advantages over static neuronal representations; it makes efficient use of neuronal dynamic range, may contribute to redundancy-reducing, sparse codes for sound and allows for simpler decoding of population responses. The circuits underlying auditory contrast gain control are still under investigation. As in the visual system, these circuits may be modulated by factors other than stimulus contrast, forming a potential neural substrate for mediating the effects of attention as well as interactions between the senses. PMID:24907308

Tug fleet and ground operations schedules and controls. Volume 2: part 1

NASA Technical Reports Server (NTRS)

1975-01-01

This Tug Fleet and Ground Operations Schedules and Controls Study addresses both ground operational data and technical requirements that span the Tug planning phase and operations phase. A similar study covering mission operations (by others) provides the complimentary flight operations details. The two studies provide the planning data requirements, resource allocation, and control milestones for supporting the requirements of the STS program. This Tug Fleet and Ground Operations Schedules and Controls Study incorporates the basic ground operations requirements and concepts provided by previous studies with the interrelationships of the planning, IUS transition, and Tug fleet operations phases. The interrelationships of these phases were studied as a system to optimize overall program benefits and minimize operational risk factors.

Time Difference Amplifier with Robust Gain Using Closed-Loop Control

NASA Astrophysics Data System (ADS)

Nakura, Toru; Mandai, Shingo; Ikeda, Makoto; Asada, Kunihiro

This paper presents a Time Difference Amplifier (TDA) that amplifies the input time difference into the output time difference. Cross coupled chains of variable delay cells with the same number of stages are applicable for TDA, and the gain is adjusted via the closed-loop control. The TDA was fabricated using 65nm CMOS and the measurement results show that the time difference gain is 4.78 at a nominal power supply while the designed gain is 4.0. The gain is stable enough to be less than 1.4% gain shift under ±10% power supply voltage fluctuation.

Automatic gain control in the echolocation system of dolphins

NASA Astrophysics Data System (ADS)

Au, Whitlow W. L.; Benoit-Bird, Kelly J.

2003-06-01

In bats and technological sonars, the gain of the receiver is progressively increased with time after the transmission of a signal to compensate for acoustic propagation loss. The current understanding of dolphin echolocation indicates that automatic gain control is not a part of their sonar system. In order to test this understanding, we have performed field measurements of free-ranging echolocating dolphins. Here we show that dolphins do possess an automatic gain control mechanism, but that it is implemented in the transmission phase rather than the receiving phase of a sonar cycle. We find that the amplitude of the dolphins' echolocation signals are highly range dependent; this amplitude increases with increasing target range, R, in a 20log(R) fashion to compensate for propagation loss. If the echolocation target is a fish school with many sound scatterers, the echoes from the school will remain nearly constant with range as the dolphin closes in on it. This characteristic has the same effect as time-varying gain in bats and technological sonar when considered from a sonar system perspective.

Fixed gain and adaptive techniques for rotorcraft vibration control

NASA Technical Reports Server (NTRS)

Roy, R. H.; Saberi, H. A.; Walker, R. A.

1985-01-01

The results of an analysis effort performed to demonstrate the feasibility of employing approximate dynamical models and frequency shaped cost functional control law desgin techniques for helicopter vibration suppression are presented. Both fixed gain and adaptive control designs based on linear second order dynamical models were implemented in a detailed Rotor Systems Research Aircraft (RSRA) simulation to validate these active vibration suppression control laws. Approximate models of fuselage flexibility were included in the RSRA simulation in order to more accurately characterize the structural dynamics. The results for both the fixed gain and adaptive approaches are promising and provide a foundation for pursuing further validation in more extensive simulation studies and in wind tunnel and/or flight tests.

Mechanisms of Gain Control by Voltage-Gated Channels in Intrinsically-Firing Neurons

PubMed Central

Patel, Ameera X.; Burdakov, Denis

2015-01-01

Gain modulation is a key feature of neural information processing, but underlying mechanisms remain unclear. In single neurons, gain can be measured as the slope of the current-frequency (input-output) relationship over any given range of inputs. While much work has focused on the control of basal firing rates and spike rate adaptation, gain control has been relatively unstudied. Of the limited studies on gain control, some have examined the roles of synaptic noise and passive somatic currents, but the roles of voltage-gated channels present ubiquitously in neurons have been less explored. Here, we systematically examined the relationship between gain and voltage-gated ion channels in a conductance-based, tonically-active, model neuron. Changes in expression (conductance density) of voltage-gated channels increased (Ca2+ channel), reduced (K+ channels), or produced little effect (h-type channel) on gain. We found that the gain-controlling ability of channels increased exponentially with the steepness of their activation within the dynamic voltage window (voltage range associated with firing). For depolarization-activated channels, this produced a greater channel current per action potential at higher firing rates. This allowed these channels to modulate gain by contributing to firing preferentially at states of higher excitation. A finer analysis of the current-voltage relationship during tonic firing identified narrow voltage windows at which the gain-modulating channels exerted their effects. As a proof of concept, we show that h-type channels can be tuned to modulate gain by changing the steepness of their activation within the dynamic voltage window. These results show how the impact of an ion channel on gain can be predicted from the relationship between channel kinetics and the membrane potential during firing. This is potentially relevant to understanding input-output scaling in a wide class of neurons found throughout the brain and other nervous systems

Automated mixed traffic vehicle control and scheduling study

NASA Technical Reports Server (NTRS)

Peng, T. K. C.; Chon, K.

1976-01-01

The operation and the expected performance of a proposed automatic guideway transit system which uses low speed automated mixed traffic vehicles (AMTVs) were analyzed. Vehicle scheduling and headway control policies were evaluated with a transit system simulation model. The effect of mixed traffic interference on the average vehicle speed was examined with a vehicle pedestrian interface model. Control parameters regulating vehicle speed were evaluated for safe stopping and passenger comfort. Some preliminary data on the cost and operation of an experimental AMTV system are included. These data were the result of a separate task conducted at JPL, and were included as background information.

A Network Scheduling Model for Distributed Control Simulation

NASA Technical Reports Server (NTRS)

Culley, Dennis; Thomas, George; Aretskin-Hariton, Eliot

2016-01-01

Distributed engine control is a hardware technology that radically alters the architecture for aircraft engine control systems. Of its own accord, it does not change the function of control, rather it seeks to address the implementation issues for weight-constrained vehicles that can limit overall system performance and increase life-cycle cost. However, an inherent feature of this technology, digital communication networks, alters the flow of information between critical elements of the closed-loop control. Whereas control information has been available continuously in conventional centralized control architectures through virtue of analog signaling, moving forward, it will be transmitted digitally in serial fashion over the network(s) in distributed control architectures. An underlying effect is that all of the control information arrives asynchronously and may not be available every loop interval of the controller, therefore it must be scheduled. This paper proposes a methodology for modeling the nominal data flow over these networks and examines the resulting impact for an aero turbine engine system simulation.

Two stage dual gate MESFET monolithic gain control amplifier for Ka-band

NASA Technical Reports Server (NTRS)

Sokolov, V.; Geddes, J.; Contolatis, A.

1987-01-01

A monolithic two stage gain control amplifier has been developed using submicron gate length dual gate MESFETs fabricated on ion implanted material. The amplifier has a gain of 12 dB at 30 GHz with a gain control range of over 30 dB. This ion implanted monolithic IC is readily integrable with other phased array receiver functions such as low noise amplifiers and phase shifters.

Changing Workplaces to Reduce Work-Family Conflict: Schedule Control in a White-Collar Organization

PubMed Central

Kelly, Erin L.; Moen, Phyllis; Tranby, Eric

2011-01-01

Work-family conflicts are common and consequential for employees, their families, and work organizations. Can workplaces be changed to reduce work-family conflict? Previous research has not been able to assess whether workplace policies or initiatives succeed in reducing work-family conflict or increasing work-family fit. Using longitudinal data collected from 608 employees of a white-collar organization before and after a workplace initiative was implemented, we investigate whether the initiative affects work-family conflict and fit, whether schedule control mediates these effects, and whether work demands, including long hours, moderate the initiative’s effects on work-family outcomes. Analyses clearly demonstrate that the workplace initiative positively affects the work-family interface, primarily by increasing employees’ schedule control. This study points to the importance of schedule control for our understanding of job quality and for management policies and practices. PMID:21580799

Changing Workplaces to Reduce Work-Family Conflict: Schedule Control in a White-Collar Organization.

PubMed

Kelly, Erin L; Moen, Phyllis; Tranby, Eric

2011-04-01

Work-family conflicts are common and consequential for employees, their families, and work organizations. Can workplaces be changed to reduce work-family conflict? Previous research has not been able to assess whether workplace policies or initiatives succeed in reducing work-family conflict or increasing work-family fit. Using longitudinal data collected from 608 employees of a white-collar organization before and after a workplace initiative was implemented, we investigate whether the initiative affects work-family conflict and fit, whether schedule control mediates these effects, and whether work demands, including long hours, moderate the initiative's effects on work-family outcomes. Analyses clearly demonstrate that the workplace initiative positively affects the work-family interface, primarily by increasing employees' schedule control. This study points to the importance of schedule control for our understanding of job quality and for management policies and practices.

Call Admission Control on Single Node Networks under Output Rate-Controlled Generalized Processor Sharing (ORC-GPS) Scheduler

NASA Astrophysics Data System (ADS)

Hanada, Masaki; Nakazato, Hidenori; Watanabe, Hitoshi

Multimedia applications such as music or video streaming, video teleconferencing and IP telephony are flourishing in packet-switched networks. Applications that generate such real-time data can have very diverse quality-of-service (QoS) requirements. In order to guarantee diverse QoS requirements, the combined use of a packet scheduling algorithm based on Generalized Processor Sharing (GPS) and leaky bucket traffic regulator is the most successful QoS mechanism. GPS can provide a minimum guaranteed service rate for each session and tight delay bounds for leaky bucket constrained sessions. However, the delay bounds for leaky bucket constrained sessions under GPS are unnecessarily large because each session is served according to its associated constant weight until the session buffer is empty. In order to solve this problem, a scheduling policy called Output Rate-Controlled Generalized Processor Sharing (ORC-GPS) was proposed in [17]. ORC-GPS is a rate-based scheduling like GPS, and controls the service rate in order to lower the delay bounds for leaky bucket constrained sessions. In this paper, we propose a call admission control (CAC) algorithm for ORC-GPS, for leaky-bucket constrained sessions with deterministic delay requirements. This CAC algorithm for ORC-GPS determines the optimal values of parameters of ORC-GPS from the deterministic delay requirements of the sessions. In numerical experiments, we compare the CAC algorithm for ORC-GPS with one for GPS in terms of schedulable region and computational complexity.

LNA with wide range of gain control and wideband interference rejection

NASA Astrophysics Data System (ADS)

Wang, Jhen-Ji; Chen, Duan-Yu

2016-10-01

This work presents a low-noise amplifier (LNA) design with a wide-range gain control characteristic that integrates adjustable current distribution and output impedance techniques. For a given gain characteristic, the proposed LNA provides better wideband interference rejection performance than conventional LNA. Moreover, the proposed LNA also has a wider gain control range than conventional LNA. Therefore, it is suitable for satellite communications systems. The simulation results demonstrate that the voltage gain control range is between 14.5 and 34.2 dB for such applications (2600 MHz); the input reflection coefficient is less than -18.9 dB; the noise figure (NF) is 1.25 dB; and the third-order intercept point (IIP3) is 4.52 dBm. The proposed LNA consumes 23.85-28.17 mW at a supply voltage of 1.8 V. It is implemented by using TSMC 0.18-um RF CMOS process technology.

Gain control in the sonar of odontocetes.

PubMed

Ya Supin, Alexander; Nachtigall, Paul E

2013-06-01

The sonar of odontocetes processes echo-signals within a wide range of echo levels. The level of echoes varies widely by tens of decibels depending on the level of the emitted sonar pulse, the target strength, the distance to the target, and the sound absorption by the water media. The auditory system of odontocetes must be capable of effective perception, analysis, and discrimination of echo-signals within all this variability. The sonar of odontocetes has several mechanisms to compensate for the echo-level variation (gain control). To date, several mechanisms of the biosonar gain control have been revealed in odontocetes: (1) adjustment of emitted sonar pulse levels (the longer the distance to the target, the higher the level of the emitted pulse), (2) short-term variation of hearing sensitivity based on forward masking of the echo by the preceding self-heard emitted pulse and subsequent release from the masking, and (3) active long-term control of hearing sensitivity. Recent investigations with the use of the auditory evoked-potential technique have demonstrated that these mechanisms effectively minimize the variation of the response to the echo when either the emitted sonar pulse level, or the target distance, or both vary within a wide range. A short review of these data is presented herein.

Coherence and interlimb force control: Effects of visual gain.

PubMed

Kang, Nyeonju; Cauraugh, James H

2018-03-06

Neural coupling across hemispheres and homologous muscles often appears during bimanual motor control. Force coupling in a specific frequency domain may indicate specific bimanual force coordination patterns. This study investigated coherence on pairs of bimanual isometric index finger force while manipulating visual gain and task asymmetry conditions. We used two visual gain conditions (low and high gain = 8 and 512 pixels/N), and created task asymmetry by manipulating coefficient ratios imposed on the left and right index finger forces (0.4:1.6; 1:1; 1.6:0.4, respectively). Unequal coefficient ratios required different contributions from each hand to the bimanual force task resulting in force asymmetry. Fourteen healthy young adults performed bimanual isometric force control at 20% of their maximal level of the summed force of both fingers. We quantified peak coherence and relative phase angle between hands at 0-4, 4-8, and 8-12 Hz, and estimated a signal-to-noise ratio of bimanual forces. The findings revealed higher peak coherence and relative phase angle at 0-4 Hz than at 4-8 and 8-12 Hz for both visual gain conditions. Further, peak coherence and relative phase angle values at 0-4 Hz were larger at the high gain than at the low gain. At the high gain, higher peak coherence at 0-4 Hz collapsed across task asymmetry conditions significantly predicted greater signal-to-noise ratio. These findings indicate that a greater level of visual information facilitates bimanual force coupling at a specific frequency range related to sensorimotor processing. Copyright © 2018 Elsevier B.V. All rights reserved.

Subtractive, divisive and non-monotonic gain control in feedforward nets linearized by noise and delays.

PubMed

Mejias, Jorge F; Payeur, Alexandre; Selin, Erik; Maler, Leonard; Longtin, André

2014-01-01

The control of input-to-output mappings, or gain control, is one of the main strategies used by neural networks for the processing and gating of information. Using a spiking neural network model, we studied the gain control induced by a form of inhibitory feedforward circuitry-also known as "open-loop feedback"-, which has been experimentally observed in a cerebellum-like structure in weakly electric fish. We found, both analytically and numerically, that this network displays three different regimes of gain control: subtractive, divisive, and non-monotonic. Subtractive gain control was obtained when noise is very low in the network. Also, it was possible to change from divisive to non-monotonic gain control by simply modulating the strength of the feedforward inhibition, which may be achieved via long-term synaptic plasticity. The particular case of divisive gain control has been previously observed in vivo in weakly electric fish. These gain control regimes were robust to the presence of temporal delays in the inhibitory feedforward pathway, which were found to linearize the input-to-output mappings (or f-I curves) via a novel variability-increasing mechanism. Our findings highlight the feedforward-induced gain control analyzed here as a highly versatile mechanism of information gating in the brain.

Subtractive, divisive and non-monotonic gain control in feedforward nets linearized by noise and delays

PubMed Central

Mejias, Jorge F.; Payeur, Alexandre; Selin, Erik; Maler, Leonard; Longtin, André

2014-01-01

The control of input-to-output mappings, or gain control, is one of the main strategies used by neural networks for the processing and gating of information. Using a spiking neural network model, we studied the gain control induced by a form of inhibitory feedforward circuitry—also known as “open-loop feedback”—, which has been experimentally observed in a cerebellum-like structure in weakly electric fish. We found, both analytically and numerically, that this network displays three different regimes of gain control: subtractive, divisive, and non-monotonic. Subtractive gain control was obtained when noise is very low in the network. Also, it was possible to change from divisive to non-monotonic gain control by simply modulating the strength of the feedforward inhibition, which may be achieved via long-term synaptic plasticity. The particular case of divisive gain control has been previously observed in vivo in weakly electric fish. These gain control regimes were robust to the presence of temporal delays in the inhibitory feedforward pathway, which were found to linearize the input-to-output mappings (or f-I curves) via a novel variability-increasing mechanism. Our findings highlight the feedforward-induced gain control analyzed here as a highly versatile mechanism of information gating in the brain. PMID:24616694

Schedules of electric shock presentation in the behavioral control of imprinted ducklings.

PubMed

Barrett, J E

1972-09-01

The behavioral effects of various schedules of electric shock presentation were investigated during and after the imprinting of Peking ducklings to moving stimuli. The behavior of following a moving imprinted stimulus was differentially controlled by a multiple schedule of punishment and avoidance that respectively suppressed and maintained following behavior. Pole-pecking, reinforced by presentations of the imprinted stimulus, was suppressed by response-produced shock (punishment); various schedules of response-independent shock and delayed punishment had an overall minimal effect. The delivery of response-independent shock in the presence of one of two stimuli, both during and after imprinting, resulted in a marked reduction in choice of the stimulus paired with shock. The experiments provide no support for a differentiation of imprinting from learning on the basis of the behavioral effects of aversive stimuli. Instead, as is the case with other organisms, the schedule under which shock is delivered to imprinted ducklings appears to be an important determinant of the temporal patterning of subsequent behavior.

Synthesis of Optimal Constant-Gain Positive-Real Controllers for Passive Systems

NASA Technical Reports Server (NTRS)

Mao, Y.; Kelkar, A. G.; Joshi, S. M.

1999-01-01

This paper presents synthesis methods for the design of constant-gain positive real controllers for passive systems. The results presented in this paper, in conjunction with the previous work by the authors on passification of non-passive systems, offer a useful synthesis tool for the design of passivity-based robust controllers for non-passive systems as well. Two synthesis approaches are given for minimizing an LQ-type performance index, resulting in optimal controller gains. Two separate algorithms, one for each of these approaches, are given. The synthesis techniques are demonstrated using two numerical examples: control of a flexible structure and longitudinal control of a fighter aircraft.

Schedule-induced masseter EMG in facial pain subjects vs. no-pain controls.

PubMed

Gramling, S E; Grayson, R L; Sullivan, T N; Schwartz, S

1997-02-01

Empirical reports suggest that oral habits (e.g., teeth clenching) may be behavioral mediators linking stress to muscle hyperreactivity and the development of facial pain. Another report suggests that excessive behavioral adjuncts develop in conjunction with fixed-time stimulus presentation. The present study assessed the extent to which the oral habits exhibited by facial pain patients are schedule-induced. Subjects with Temporomandibular Disorder (TMD) symptomatology (n = 15) and pain-free controls (n = 15) participated in a 4-phase experiment (adaptation, baseline, task, recovery) designed to elicit schedule-induced behaviors. Self-report of oral habits and negative affect were recorded after each phase. Objective measures of oral habits were obtained via behavioral observation and masseter EMG recordings. Results revealed that negative arousal significantly increased during the fixed-time (FT) task and was also associated with increased oral habits among the TMD subjects. Moreover, 40% of the TMD subjects and none of the controls exhibited a pattern of EMG elevations in the early part of the inter-stimulus interval that met a strict criteria for scheduled-induced behavior per se. Taken together, these results suggest that the TMD subjects were engaging in schedule-induced oral habits. The adjunctive behavior literature seems to provide a plausible explanation as to how oral habits develop and are maintained in TMD patients, despite their painful consequences.

Flexible Schedules and Shift Work.

ERIC Educational Resources Information Center

Beers, Thomas M.

2000-01-01

Flexible work hours have gained prominence, as more than 25 million workers (27.6% of all full-time workers) can now vary their schedules. However, there has been little change since the mid-1980s in the proportion who work a shift other than a regular daytime shift. (JOW)

Gain control of photomultiplier tubes used in detecting differential absorption lidar returns

NASA Technical Reports Server (NTRS)

Allen, Robert J. (Inventor)

1989-01-01

A technique for controlling the gain of a photomultiplier tube (PMT) 20. A voltage divider (resistors 45-49 in FIG. 1 and zener diodes 60-65 in FIG. 3) is used to control the potentials on dynodes 5, 7, and 9 of PMT 20. Transistor switches 53 and 58 provide the control of the voltage divider in FIG. 1 and photodiodes 66, 67 and 70 provide the control in FIG. 3. The gain control of PMT 20 is in the range from 100% to less than 0.001% (100,000 to 1).

Anodal transcranial direct current stimulation over the primary motor cortex does not enhance the learning benefits of self-controlled feedback schedules.

PubMed

Carter, Michael J; Smith, Victoria; Carlsen, Anthony N; Ste-Marie, Diane M

2018-05-01

A distinct learning advantage has been shown when participants control their knowledge of results (KR) scheduling during practice compared to when the same KR schedule is imposed on the learner without choice (i.e., yoked schedules). Although the learning advantages of self-controlled KR schedules are well-documented, the brain regions contributing to these advantages remain unknown. Identifying key brain regions would not only advance our theoretical understanding of the mechanisms underlying self-controlled learning advantages, but would also highlight regions that could be targeted in more applied settings to boost the already beneficial effects of self-controlled KR schedules. Here, we investigated whether applying anodal transcranial direct current stimulation (tDCS) to the primary motor cortex (M1) would enhance the typically found benefits of learning a novel motor skill with a self-controlled KR schedule. Participants practiced a spatiotemporal task in one of four groups using a factorial combination of KR schedule (self-controlled vs. yoked) and tDCS (anodal vs. sham). Testing occurred on two consecutive days with spatial and temporal accuracy measured on both days and learning was assessed using 24-h retention and transfer tests without KR. All groups improved their performance in practice and a significant effect for practicing with a self-controlled KR schedule compared to a yoked schedule was found for temporal accuracy in transfer, but a similar advantage was not evident in retention. There were no significant differences as a function of KR schedule or tDCS for spatial accuracy in retention or transfer. The lack of a significant tDCS effect suggests that M1 may not strongly contribute to self-controlled KR learning advantages; however, caution is advised with this interpretation as typical self-controlled learning benefits were not strongly replicated in the present experiment.

The control gain region for synchronization in non-diffusively coupled complex networks

NASA Astrophysics Data System (ADS)

Gequn, Liu; Wenhui, Li; Huijie, Yang; Knowles, Gareth

2014-07-01

The control gain region for synchronization of non-diffusively coupled networks was studied with respect to three conditions: synchronization, synchronization in finite time, and synchronization in the minimum time. Based on cancellation control methodology and master stability function formalism, we found that a complete feasible control gain region may be bounded, unbounded, empty or a union of several bounded and unbounded regions, with a similar shape to the synchronized region. An interesting possibility emerged that a network could be synchronized by both negative and positive feedback control simultaneously. By bridging synchronizability and synchronizing response speeds with a settling time index, we have developed timed synchronized region (TSR) as a substitute for the classical synchronized region to study finite time synchronization. As for the last condition, a graphical method was developed to estimate control gain with the minimum synchronization time (CGMST). Each condition has examples provided for illustration and verification.

Scheduled power tracking control of the wind-storage hybrid system based on the reinforcement learning theory

NASA Astrophysics Data System (ADS)

Li, Ze

2017-09-01

In allusion to the intermittency and uncertainty of the wind electricity, energy storage and wind generator are combined into a hybrid system to improve the controllability of the output power. A scheduled power tracking control method is proposed based on the reinforcement learning theory and Q-learning algorithm. In this method, the state space of the environment is formed with two key factors, i.e. the state of charge of the energy storage and the difference value between the actual wind power and scheduled power, the feasible action is the output power of the energy storage, and the corresponding immediate rewarding function is designed to reflect the rationality of the control action. By interacting with the environment and learning from the immediate reward, the optimal control strategy is gradually formed. After that, it could be applied to the scheduled power tracking control of the hybrid system. Finally, the rationality and validity of the method are verified through simulation examples.

Modern digital flight control system design for VTOL aircraft

NASA Technical Reports Server (NTRS)

Broussard, J. R.; Berry, P. W.; Stengel, R. F.

1979-01-01

Methods for and results from the design and evaluation of a digital flight control system (DFCS) for a CH-47B helicopter are presented. The DFCS employed proportional-integral control logic to provide rapid, precise response to automatic or manual guidance commands while following conventional or spiral-descent approach paths. It contained altitude- and velocity-command modes, and it adapted to varying flight conditions through gain scheduling. Extensive use was made of linear systems analysis techniques. The DFCS was designed, using linear-optimal estimation and control theory, and the effects of gain scheduling are assessed by examination of closed-loop eigenvalues and time responses.

Modeling and Control for Microgrids

NASA Astrophysics Data System (ADS)

Steenis, Joel

Traditional approaches to modeling microgrids include the behavior of each inverter operating in a particular network configuration and at a particular operating point. Such models quickly become computationally intensive for large systems. Similarly, traditional approaches to control do not use advanced methodologies and suffer from poor performance and limited operating range. In this document a linear model is derived for an inverter connected to the Thevenin equivalent of a microgrid. This model is then compared to a nonlinear simulation model and analyzed using the open and closed loop systems in both the time and frequency domains. The modeling error is quantified with emphasis on its use for controller design purposes. Control design examples are given using a Glover McFarlane controller, gain scheduled Glover McFarlane controller, and bumpless transfer controller which are compared to the standard droop control approach. These examples serve as a guide to illustrate the use of multi-variable modeling techniques in the context of robust controller design and show that gain scheduled MIMO control techniques can extend the operating range of a microgrid. A hardware implementation is used to compare constant gain droop controllers with Glover McFarlane controllers and shows a clear advantage of the Glover McFarlane approach.

L∞-gain adaptive fuzzy fault accommodation control design for nonlinear time-delay systems.

PubMed

Wu, Huai-Ning; Qiang, Xiao-Hong; Guo, Lei

2011-06-01

In this paper, an adaptive fuzzy fault accommodation (FA) control design with a guaranteed L(∞)-gain performance is developed for a class of nonlinear time-delay systems with persistent bounded disturbances. Using the Lyapunov technique and the Razumikhin-type lemma, the existence condition of the L(∞) -gain adaptive fuzzy FA controllers is provided in terms of linear matrix inequalities (LMIs). In the proposed FA scheme, a fuzzy logic system is employed to approximate the unknown term in the derivative of the Lyapunov function due to the unknown fault function; a continuous-state feedback control strategy is adopted for the control design to avoid the undesirable chattering phenomenon. The resulting FA controllers can ensure that every response of the closed-loop system is uniformly ultimately bounded with a guaranteed L(∞)-gain performance in the presence of a fault. Moreover, by the existing LMI optimization technique, a suboptimal controller is obtained in the sense of minimizing an upper bound of the L(∞)-gain. Finally, the achieved simulation results on the FA control of a continuous stirred tank reactor (CSTR) show the effectiveness of the proposed design procedure.

Model of visual contrast gain control and pattern masking

NASA Technical Reports Server (NTRS)

Watson, A. B.; Solomon, J. A.

1997-01-01

We have implemented a model of contrast gain and control in human vision that incorporates a number of key features, including a contrast sensitivity function, multiple oriented bandpass channels, accelerating nonlinearities, and a devisive inhibitory gain control pool. The parameters of this model have been optimized through a fit to the recent data that describe masking of a Gabor function by cosine and Gabor masks [J. M. Foley, "Human luminance pattern mechanisms: masking experiments require a new model," J. Opt. Soc. Am. A 11, 1710 (1994)]. The model achieves a good fit to the data. We also demonstrate how the concept of recruitment may accommodate a variant of this model in which excitatory and inhibitory paths have a common accelerating nonlinearity, but which include multiple channels tuned to different levels of contrast.

Learning to walk with an adaptive gain proportional myoelectric controller for a robotic ankle exoskeleton.

PubMed

Koller, Jeffrey R; Jacobs, Daniel A; Ferris, Daniel P; Remy, C David

2015-11-04

Robotic ankle exoskeletons can provide assistance to users and reduce metabolic power during walking. Our research group has investigated the use of proportional myoelectric control for controlling robotic ankle exoskeletons. Previously, these controllers have relied on a constant gain to map user's muscle activity to actuation control signals. A constant gain may act as a constraint on the user, so we designed a controller that dynamically adapts the gain to the user's myoelectric amplitude. We hypothesized that an adaptive gain proportional myoelectric controller would reduce metabolic energy expenditure compared to walking with the ankle exoskeleton unpowered because users could choose their preferred control gain. We tested eight healthy subjects walking with the adaptive gain proportional myoelectric controller with bilateral ankle exoskeletons. The adaptive gain was updated each stride such that on average the user's peak muscle activity was mapped to maximal power output of the exoskeleton. All subjects participated in three identical training sessions where they walked on a treadmill for 50 minutes (30 minutes of which the exoskeleton was powered) at 1.2 ms(-1). We calculated and analyzed metabolic energy consumption, muscle recruitment, inverse kinematics, inverse dynamics, and exoskeleton mechanics. Using our controller, subjects achieved a metabolic reduction similar to that seen in previous work in about a third of the training time. The resulting controller gain was lower than that seen in previous work (β=1.50±0.14 versus a constant β=2). The adapted gain allowed users more total ankle joint power than that of unassisted walking, increasing ankle power in exchange for a decrease in hip power. Our findings indicate that humans prefer to walk with greater ankle mechanical power output than their unassisted gait when provided with an ankle exoskeleton using an adaptive controller. This suggests that robotic assistance from an exoskeleton can allow

Tool for Merging Proposals Into DSN Schedules

NASA Technical Reports Server (NTRS)

Khanampornpan, Teerapat; Kwok, John; Call, Jared

2008-01-01

A Practical Extraction and Reporting Language (Perl) script called merge7da has been developed to facilitate determination, by a project scheduler in NASA's Deep Space Network, of whether a proposal for use of the DSN could create a conflict with the current DSN schedule. Prior to the development of merge7da, there was no way to quickly identify potential schedule conflicts: it was necessary to submit a proposal and wait a day or two for a response from a DSN scheduling facility. By using merge7da to detect and eliminate potential schedule conflicts before submitting a proposal, a project scheduler saves time and gains assurance that the proposal will probably be accepted. merge7da accepts two input files, one of which contains the current DSN schedule and is in a DSN-standard format called '7da'. The other input file contains the proposal and is in another DSN-standard format called 'C1/C2'. merge7da processes the two input files to produce a merged 7da-format output file that represents the DSN schedule as it would be if the proposal were to be adopted. This 7da output file can be loaded into various DSN scheduling software tools now in use.

Design of optimally normal minimum gain controllers by continuation method

NASA Technical Reports Server (NTRS)

Lim, K. B.; Juang, J.-N.; Kim, Z. C.

1989-01-01

A measure of the departure from normality is investigated for system robustness. An attractive feature of the normality index is its simplicity for pole placement designs. To allow a tradeoff between system robustness and control effort, a cost function consisting of the sum of a norm of weighted gain matrix and a normality index is minimized. First- and second-order necessary conditions for the constrained optimization problem are derived and solved by a Newton-Raphson algorithm imbedded into a one-parameter family of neighboring zero problems. The method presented allows the direct computation of optimal gains in terms of robustness and control effort for pole placement problems.

Flexible Contrast Gain Control in the Right Hemisphere

ERIC Educational Resources Information Center

Okubo, Matia; Nicholls, Michael E. R.

2005-01-01

This study investigates whether the right hemisphere has more flexible contrast gain control settings for the identification of spatial frequency. Right-handed participants identified 1 and 9 cycles per degree sinusoidal gratings presented either to the left visual field-right hemisphere (LVF-RH) or the right visual field-left hemisphere (RVF-LH).…

Protocols for distributive scheduling

NASA Technical Reports Server (NTRS)

Richards, Stephen F.; Fox, Barry

1993-01-01

The increasing complexity of space operations and the inclusion of interorganizational and international groups in the planning and control of space missions lead to requirements for greater communication, coordination, and cooperation among mission schedulers. These schedulers must jointly allocate scarce shared resources among the various operational and mission oriented activities while adhering to all constraints. This scheduling environment is complicated by such factors as the presence of varying perspectives and conflicting objectives among the schedulers, the need for different schedulers to work in parallel, and limited communication among schedulers. Smooth interaction among schedulers requires the use of protocols that govern such issues as resource sharing, authority to update the schedule, and communication of updates. This paper addresses the development and characteristics of such protocols and their use in a distributed scheduling environment that incorporates computer-aided scheduling tools. An example problem is drawn from the domain of space shuttle mission planning.

Transference effects of prior non-contingent reinforcement on the acquisition of temporal control on fixed-interval schedules.

PubMed

López, Florente; Menez, Marina

2012-07-01

In two experiments we examined the influence of response and time factors on the speed of acquisition of temporal control on FI schedules. In Experiment 1, prior exposure to FT accelerated the development of temporal control on FI schedules of the same temporal value. It was also found that the slower acquisition on FI with prior RT was similar to that of rats with prior standard training. In Experiment 2, prior exposure to FT accelerated the development of temporal control on a FI schedule with a threefold increase in temporal value. Additionally, it was found that with prior FI 30s training, acquisition of temporal control on FI 90s was even faster than with prior FT 30s. Measures of head-entries into the feeder along the experiments indicated that temporal control was already developed during the periodic but not during the non-periodic histories and that this control transferred to lever press during FI testing phase. Copyright © 2012 Elsevier B.V. All rights reserved.

Impact of referral letters on scheduling of hospital appointments: a randomised control trial

PubMed Central

Jiwa, Moyez; Meng, Xingqiong; O’Shea, Carolyn; Magin, Parker; Dadich, Ann; Pillai, Vinita

2014-01-01

Background Communication is essential for triage, but intervention trials to improve it are scarce. Referral Writer (RW), a referral letter software program, enables documentation of clinical data and extracts relevant patient details from clinical software. Aim To evaluate whether specialists are more confident about scheduling appointments when they receive more information in referral letters. Design and setting Single-blind, parallel-groups, controlled design with a 1:1 randomisation. Australian GPs watched video vignettes virtually. Method GPs wrote referral letters after watching vignettes of patients with cancer symptoms. Letter content was scored against a benchmark. The proportions of referral letters triagable by a specialist with confidence, and in which the specialist was confident the patient had potentially life-limiting pathology were determined. Categorical outcomes were tested with χ2 and continuous outcomes with t-tests. A random-effects logistic model assessed the influence of group randomisation (RW versus control), GP demographics, clinical specialty, and specialist referral assessor on specialist confidence in the information provided. Results The intervention (RW) group referred more patients and scored significantly higher on information relayed (mean difference 21.6 [95% confidence intervals {CI} = 20.1 to 23.2]). There was no difference in the proportion of letters for which specialists were confident they had sufficient information for appointment scheduling (RW 77.7% versus control 80.6%, P = 0.16). In the logistic model, limited agreement among specialists contributed substantially to the observed differences in appointment scheduling (P = 35% [95% CI 16% to 59%]). Conclusion In isolation, referral letter templates are unlikely to improve the scheduling of specialist appointments, even when more information is relayed. PMID:24982494

Impact of referral letters on scheduling of hospital appointments: a randomised control trial.

PubMed

Jiwa, Moyez; Meng, Xingqiong; O'Shea, Carolyn; Magin, Parker; Dadich, Ann; Pillai, Vinita

2014-07-01

Communication is essential for triage, but intervention trials to improve it are scarce. Referral Writer (RW), a referral letter software program, enables documentation of clinical data and extracts relevant patient details from clinical software. To evaluate whether specialists are more confident about scheduling appointments when they receive more information in referral letters. Single-blind, parallel-groups, controlled design with a 1:1 randomisation. Australian GPs watched video vignettes virtually. GPs wrote referral letters after watching vignettes of patients with cancer symptoms. Letter content was scored against a benchmark. The proportions of referral letters triagable by a specialist with confidence, and in which the specialist was confident the patient had potentially life-limiting pathology were determined. Categorical outcomes were tested with χ(2) and continuous outcomes with t-tests. A random-effects logistic model assessed the influence of group randomisation (RW versus control), GP demographics, clinical specialty, and specialist referral assessor on specialist confidence in the information provided. The intervention (RW) group referred more patients and scored significantly higher on information relayed (mean difference 21.6 [95% confidence intervals {CI} = 20.1 to 23.2]). There was no difference in the proportion of letters for which specialists were confident they had sufficient information for appointment scheduling (RW 77.7% versus control 80.6%, P = 0.16). In the logistic model, limited agreement among specialists contributed substantially to the observed differences in appointment scheduling (P = 35% [95% CI 16% to 59%]). In isolation, referral letter templates are unlikely to improve the scheduling of specialist appointments, even when more information is relayed. © British Journal of General Practice 2014.

A controlled genetic algorithm by fuzzy logic and belief functions for job-shop scheduling.

PubMed

Hajri, S; Liouane, N; Hammadi, S; Borne, P

2000-01-01

Most scheduling problems are highly complex combinatorial problems. However, stochastic methods such as genetic algorithm yield good solutions. In this paper, we present a controlled genetic algorithm (CGA) based on fuzzy logic and belief functions to solve job-shop scheduling problems. For better performance, we propose an efficient representational scheme, heuristic rules for creating the initial population, and a new methodology for mixing and computing genetic operator probabilities.

Stability Assessment and Tuning of an Adaptively Augmented Classical Controller for Launch Vehicle Flight Control

NASA Technical Reports Server (NTRS)

VanZwieten, Tannen; Zhu, J. Jim; Adami, Tony; Berry, Kyle; Grammar, Alex; Orr, Jeb S.; Best, Eric A.

2014-01-01

Recently, a robust and practical adaptive control scheme for launch vehicles [ [1] has been introduced. It augments a classical controller with a real-time loop-gain adaptation, and it is therefore called Adaptive Augmentation Control (AAC). The loop-gain will be increased from the nominal design when the tracking error between the (filtered) output and the (filtered) command trajectory is large; whereas it will be decreased when excitation of flex or sloshing modes are detected. There is a need to determine the range and rate of the loop-gain adaptation in order to retain (exponential) stability, which is critical in vehicle operation, and to develop some theoretically based heuristic tuning methods for the adaptive law gain parameters. The classical launch vehicle flight controller design technics are based on gain-scheduling, whereby the launch vehicle dynamics model is linearized at selected operating points along the nominal tracking command trajectory, and Linear Time-Invariant (LTI) controller design techniques are employed to ensure asymptotic stability of the tracking error dynamics, typically by meeting some prescribed Gain Margin (GM) and Phase Margin (PM) specifications. The controller gains at the design points are then scheduled, tuned and sometimes interpolated to achieve good performance and stability robustness under external disturbances (e.g. winds) and structural perturbations (e.g. vehicle modeling errors). While the GM does give a bound for loop-gain variation without losing stability, it is for constant dispersions of the loop-gain because the GM is based on frequency-domain analysis, which is applicable only for LTI systems. The real-time adaptive loop-gain variation of the AAC effectively renders the closed-loop system a time-varying system, for which it is well-known that the LTI system stability criterion is neither necessary nor sufficient when applying to a Linear Time-Varying (LTV) system in a frozen-time fashion. Therefore, a

Linear parameter varying representations for nonlinear control design

NASA Astrophysics Data System (ADS)

Carter, Lance Huntington

Linear parameter varying (LPV) systems are investigated as a framework for gain-scheduled control design and optimal hybrid control. An LPV system is defined as a linear system whose dynamics depend upon an a priori unknown but measurable exogenous parameter. A gain-scheduled autopilot design is presented for a bank-to-turn (BTT) missile. The method is novel in that the gain-scheduled design does not involve linearizations about operating points. Instead, the missile dynamics are brought to LPV form via a state transformation. This idea is applied to the design of a coupled longitudinal/lateral BTT missile autopilot. The pitch and yaw/roll dynamics are separately transformed to LPV form, where the cross axis states are treated as "exogenous" parameters. These are actually endogenous variables, so such a plant is called "quasi-LPV." Once in quasi-LPV form, a family of robust controllers using mu synthesis is designed for both the pitch and yaw/roll channels, using angle-of-attack and roll rate as the scheduling variables. The closed-loop time response is simulated using the original nonlinear model and also using perturbed aerodynamic coefficients. Modeling and control of engine idle speed is investigated using LPV methods. It is shown how generalized discrete nonlinear systems may be transformed into quasi-LPV form. A discrete nonlinear engine model is developed and expressed in quasi-LPV form with engine speed as the scheduling variable. An example control design is presented using linear quadratic methods. Simulations are shown comparing the LPV based controller performance to that using PID control. LPV representations are also shown to provide a setting for hybrid systems. A hybrid system is characterized by control inputs consisting of both analog signals and discrete actions. A solution is derived for the optimal control of hybrid systems with generalized cost functions. This is shown to be computationally intensive, so a suboptimal strategy is proposed that

IET. Control and equipment building (TAN620) floor plan. Schedule of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

IET. Control and equipment building (TAN-620) floor plan. Schedule of furniture and equipment. Ralph M. Parsons 902-4-ANP-A 320. Date: February 1954. Approved by INEEL Classification Office for public release. INEEL index code no. 035-0620-00-693-106905 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

Dynamic modulation of visual and electrosensory gains for locomotor control

PubMed Central

Sutton, Erin E.; Demir, Alican; Stamper, Sarah A.; Fortune, Eric S.; Cowan, Noah J.

2016-01-01

Animal nervous systems resolve sensory conflict for the control of movement. For example, the glass knifefish, Eigenmannia virescens, relies on visual and electrosensory feedback as it swims to maintain position within a moving refuge. To study how signals from these two parallel sensory streams are used in refuge tracking, we constructed a novel augmented reality apparatus that enables the independent manipulation of visual and electrosensory cues to freely swimming fish (n = 5). We evaluated the linearity of multisensory integration, the change to the relative perceptual weights given to vision and electrosense in relation to sensory salience, and the effect of the magnitude of sensory conflict on sensorimotor gain. First, we found that tracking behaviour obeys superposition of the sensory inputs, suggesting linear sensorimotor integration. In addition, fish rely more on vision when electrosensory salience is reduced, suggesting that fish dynamically alter sensorimotor gains in a manner consistent with Bayesian integration. However, the magnitude of sensory conflict did not significantly affect sensorimotor gain. These studies lay the theoretical and experimental groundwork for future work investigating multisensory control of locomotion. PMID:27170650

C/SCSC overview: approach, implementation, use. [Cost/Schedule Control Systems Criteria

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

Turf, Larry

1979-01-01

An overview of the Cost/Schedule Control System Criteria, known as C/SCS or C/S Squared is pesented. In the mid-1960s, several DOD service agencies embarked on a new performance measurement concept to track cost and schedule performance on major DOD programs. The performance measurement concept of C/SCS has expanded from DOD use to the Department of Energy (PMS), NASA (533 reports), and private industry such as shipbuilding, utilities, and construction. This paper describes the C/SCSC with the events leading to the C/SCS requirement, how to approach the requirement, and discusses implementing and using the system. Many government publications, directives, and instructionsmore » on the subject are listed in the publication.« less

Decentralized Control of Scheduling in Distributed Systems.

DTIC Science & Technology

1983-03-18

the job scheduling algorithm adapts to the changing busyness of the various hosts in the system. The environment in which the job scheduling entities...resources and processes that constitute the node and a set of interfaces for accessing these processes and resources. The structure of a node could change ...parallel. Chang [CHNG82] has also described some algorithms for detecting properties of general graphs by traversing paths in a graph in parallel. One of

A Model-Driven Co-Design Framework for Fusing Control and Scheduling Viewpoints.

PubMed

Sundharam, Sakthivel Manikandan; Navet, Nicolas; Altmeyer, Sebastian; Havet, Lionel

2018-02-20

Model-Driven Engineering (MDE) is widely applied in the industry to develop new software functions and integrate them into the existing run-time environment of a Cyber-Physical System (CPS). The design of a software component involves designers from various viewpoints such as control theory, software engineering, safety, etc. In practice, while a designer from one discipline focuses on the core aspects of his field (for instance, a control engineer concentrates on designing a stable controller), he neglects or considers less importantly the other engineering aspects (for instance, real-time software engineering or energy efficiency). This may cause some of the functional and non-functional requirements not to be met satisfactorily. In this work, we present a co-design framework based on timing tolerance contract to address such design gaps between control and real-time software engineering. The framework consists of three steps: controller design, verified by jitter margin analysis along with co-simulation, software design verified by a novel schedulability analysis, and the run-time verification by monitoring the execution of the models on target. This framework builds on CPAL (Cyber-Physical Action Language), an MDE design environment based on model-interpretation, which enforces a timing-realistic behavior in simulation through timing and scheduling annotations. The application of our framework is exemplified in the design of an automotive cruise control system.

A Model-Driven Co-Design Framework for Fusing Control and Scheduling Viewpoints

PubMed Central

Navet, Nicolas; Havet, Lionel

2018-01-01

Model-Driven Engineering (MDE) is widely applied in the industry to develop new software functions and integrate them into the existing run-time environment of a Cyber-Physical System (CPS). The design of a software component involves designers from various viewpoints such as control theory, software engineering, safety, etc. In practice, while a designer from one discipline focuses on the core aspects of his field (for instance, a control engineer concentrates on designing a stable controller), he neglects or considers less importantly the other engineering aspects (for instance, real-time software engineering or energy efficiency). This may cause some of the functional and non-functional requirements not to be met satisfactorily. In this work, we present a co-design framework based on timing tolerance contract to address such design gaps between control and real-time software engineering. The framework consists of three steps: controller design, verified by jitter margin analysis along with co-simulation, software design verified by a novel schedulability analysis, and the run-time verification by monitoring the execution of the models on target. This framework builds on CPAL (Cyber-Physical Action Language), an MDE design environment based on model-interpretation, which enforces a timing-realistic behavior in simulation through timing and scheduling annotations. The application of our framework is exemplified in the design of an automotive cruise control system. PMID:29461489

Decentralized Control of Scheduling in Distributed Systems.

DTIC Science & Technology

1983-12-15

does not perform quite as well as the 10 state system, but is less sensitive to changes in scheduling period. It performs best when scheduling is...intra-process concerns. We extend theLr concept of a process to inolude Inter -ress comunication. That is. various form of send and receive primitives...Current busyness of each site based on some responses to requests for bids. A received bid is utilization factor. adjusted by incrementing it by a

Preview Scheduled Model Predictive Control For Horizontal Axis Wind Turbines

NASA Astrophysics Data System (ADS)

Laks, Jason H.

This research investigates the use of model predictive control (MPC) in application to wind turbine operation from start-up to cut-out. The studies conducted are focused on the design of an MPC controller for a 650˜KW, three-bladed horizontal axis turbine that is in operation at the National Renewable Energy Laboratory's National Wind Technology Center outside of Golden, Colorado. This turbine is at the small end of utility scale turbines, but it provides advanced instrumentation and control capabilities, and there is a good probability that the approach developed in simulation for this thesis, will be field tested on the actual turbine. A contribution of this thesis is a method to combine the use of preview measurements with MPC while also providing regulation of turbine speed and cyclic blade loading. A common MPC technique provides integral-like control to achieve offset-free operation. At the same time in wind turbine applications, multiple studies have developed "feed-forward" controls based on applying a gain to an estimate of the wind speed changes obtained from an observer incorporating a disturbance model. These approaches are based on a technique that can be referred to as disturbance accommodating control (DAC). In this thesis, it is shown that offset-free tracking MPC is equivalent to a DAC approach when the disturbance gain is computed to satisfy a regulator equation. Although the MPC literature has recognized that this approach provides "structurally stable" disturbance rejection and tracking, this step is not typically divorced from the MPC computations repeated each sample hit. The DAC formulation is conceptually simpler, and essentially uncouples regulation considerations from MPC related issues. This thesis provides a self contained proof that the DAC formulation (an observer-controller and appropriate disturbance gain) provides structurally stable regulation.

A field test of procedures for evaluating and scheduling white-pine weevil control

Treesearch

Robert P. Ford; Robert L. Talerico; D. Gordon Mott

1965-01-01

Procedures have recently been developed that permit economic and biological information to be integrated in making decisions about the need for control against the white-pine weevil, and in scheduling control in young white pine plantations. The procedures are based upon studies of the magnitude of economic losses that result from weevil attack in white pine and upon...

A learning flight control system for the F8-DFBW aircraft. [Digital Fly-By-Wire

NASA Technical Reports Server (NTRS)

Montgomery, R. C.; Mekel, R.; Nachmias, S.

1978-01-01

This report contains a complete description of a learning control system designed for the F8-DFBW aircraft. The system is parameter-adaptive with the additional feature that it 'learns' the variation of the control system gains needed over the flight envelope. It, thus, generates and modifies its gain schedule when suitable data are available. The report emphasizes the novel learning features of the system: the forms of representation of the flight envelope and the process by which identified parameters are used to modify the gain schedule. It contains data taken during piloted real-time 6 degree-of-freedom simulations that were used to develop and evaluate the system.

Limiting weight gain in overweight and obese women during pregnancy to improve health outcomes: the LIMIT randomised controlled trial

PubMed Central

2011-01-01

Background Obesity is a significant global health problem, with the proportion of women entering pregnancy with a body mass index greater than or equal to 25 kg/m2 approaching 50%. Obesity during pregnancy is associated with a well-recognised increased risk of adverse health outcomes both for the woman and her infant, however there is more limited information available regarding effective interventions to improve health outcomes. The aims of this randomised controlled trial are to assess whether the implementation of a package of dietary and lifestyle advice to overweight and obese women during pregnancy to limit gestational weight gain is effective in improving maternal, fetal and infant health outcomes. Methods/Design Design: Multicentred randomised, controlled trial. Inclusion Criteria: Women with a singleton, live gestation between 10+0-20+0 weeks who are obese or overweight (defined as body mass index greater than or equal to 25 kg/m2), at the first antenatal visit. Trial Entry & Randomisation: Eligible, consenting women will be randomised between 10+0 and 20+0 weeks gestation using a central telephone randomisation service, and randomisation schedule prepared by non-clinical research staff with balanced variable blocks. Stratification will be according to maternal BMI at trial entry, parity, and centre where planned to give birth. Treatment Schedules: Women randomised to the Dietary and Lifestyle Advice Group will receive a series of inputs from research assistants and research dietician to limit gestational weight gain, and will include a combination of dietary, exercise and behavioural strategies. Women randomised to the Standard Care Group will continue to receive their pregnancy care according to local hospital guidelines, which does not currently include routine provision of dietary, lifestyle and behavioural advice. Outcome assessors will be blinded to the allocated treatment group. Primary Study Outcome: infant large for gestational age (defined as

Tuning and performance evaluation of PID controller for superheater steam temperature control of 200 MW boiler using gain phase assignment algorithm

NASA Astrophysics Data System (ADS)

Begum, A. Yasmine; Gireesh, N.

2018-04-01

In superheater, steam temperature is controlled in a cascade control loop. The cascade control loop consists of PI and PID controllers. To improve the superheater steam temperature control the controller's gains in a cascade control loop has to be tuned efficiently. The mathematical model of the superheater is derived by sets of nonlinear partial differential equations. The tuning methods taken for study here are designed for delay plus first order transfer function model. Hence from the dynamical model of the superheater, a FOPTD model is derived using frequency response method. Then by using Chien-Hrones-Reswick Tuning Algorithm and Gain-Phase Assignment Algorithm optimum controller gains has been found out based on the least value of integral time weighted absolute error.

External locus of control contributes to racial disparities in memory and reasoning training gains in ACTIVE

PubMed Central

Zahodne, Laura B.; Meyer, Oanh L.; Choi, Eunhee; Thomas, Michael L.; Willis, Sherry L.; Marsiske, Michael; Gross, Alden L.; Rebok, George W.; Parisi, Jeanine M.

2015-01-01

Racial disparities in cognitive outcomes may be partly explained by differences in locus of control. African Americans report more external locus of control than non-Hispanic Whites, and external locus of control is associated with poorer health and cognition. The aims of this study were to compare cognitive training gains between African American and non-Hispanic White participants in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study and determine whether racial differences in training gains are mediated by locus of control. The sample comprised 2,062 (26% African American) adults aged 65 and older who participated in memory, reasoning, or speed training. Latent growth curve models evaluated predictors of 10-year cognitive trajectories separately by training group. Multiple group modeling examined associations between training gains and locus of control across racial groups. Compared to non-Hispanic Whites, African Americans evidenced less improvement in memory and reasoning performance after training. These effects were partially mediated by locus of control, controlling for age, sex, education, health, depression, testing site, and initial cognitive ability. African Americans reported more external locus of control, which was associated with smaller training gains. External locus of control also had a stronger negative association with reasoning training gain for African Americans than for Whites. No racial difference in training gain was identified for speed training. Future intervention research with African Americans should test whether explicitly targeting external locus of control leads to greater cognitive improvement following cognitive training. PMID:26237116

Redesign of a Variable-Gain Output Feedback Longitudinal Controller Flown on the High-Alpha Research Vehicle (HARV)

NASA Technical Reports Server (NTRS)

Ostroff, Aaron J.

1998-01-01

This paper describes a redesigned longitudinal controller that flew on the High-Alpha Research Vehicle (HARV) during calendar years (CY) 1995 and 1996. Linear models are developed for both the modified controller and a baseline controller that was flown in CY 1994. The modified controller was developed with three gain sets for flight evaluation, and several linear analysis results are shown comparing the gain sets. A Neal-Smith flying qualities analysis shows that performance for the low- and medium-gain sets is near the level 1 boundary, depending upon the bandwidth assumed, whereas the high-gain set indicates a sensitivity problem. A newly developed high-alpha Bode envelope criterion indicates that the control system gains may be slightly high, even for the low-gain set. A large motion-base simulator in the United Kingdom was used to evaluate the various controllers. Desired performance, which appeared to be satisfactory for flight, was generally met with both the low- and medium-gain sets. Both the high-gain set and the baseline controller were very sensitive, and it was easy to generate pilot-induced oscillation (PIO) in some of the target-tracking maneuvers. Flight target-tracking results varied from level 1 to level 3 and from no sensitivity to PIO. These results were related to pilot technique and whether actuator rate saturation was encountered.

Range Scheduling Aid (RSA)

NASA Technical Reports Server (NTRS)

Logan, J. R.; Pulvermacher, M. K.

1991-01-01

Range Scheduling Aid (RSA) is presented in the form of the viewgraphs. The following subject areas are covered: satellite control network; current and new approaches to range scheduling; MITRE tasking; RSA features; RSA display; constraint based analytic capability; RSA architecture; and RSA benefits.

External locus of control contributes to racial disparities in memory and reasoning training gains in ACTIVE.

PubMed

Zahodne, Laura B; Meyer, Oanh L; Choi, Eunhee; Thomas, Michael L; Willis, Sherry L; Marsiske, Michael; Gross, Alden L; Rebok, George W; Parisi, Jeanine M

2015-09-01

Racial disparities in cognitive outcomes may be partly explained by differences in locus of control. African Americans report more external locus of control than non-Hispanic Whites, and external locus of control is associated with poorer health and cognition. The aims of this study were to compare cognitive training gains between African American and non-Hispanic White participants in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study and determine whether racial differences in training gains are mediated by locus of control. The sample comprised 2,062 (26% African American) adults aged 65 and older who participated in memory, reasoning, or speed training. Latent growth curve models evaluated predictors of 10-year cognitive trajectories separately by training group. Multiple group modeling examined associations between training gains and locus of control across racial groups. Compared to non-Hispanic Whites, African Americans evidenced less improvement in memory and reasoning performance after training. These effects were partially mediated by locus of control, controlling for age, sex, education, health, depression, testing site, and initial cognitive ability. African Americans reported more external locus of control, which was associated with smaller training gains. External locus of control also had a stronger negative association with reasoning training gain for African Americans than for Whites. No racial difference in training gain was identified for speed training. Future intervention research with African Americans should test whether explicitly targeting external locus of control leads to greater cognitive improvement following cognitive training. (c) 2015 APA, all rights reserved).

Musicianship enhances ipsilateral and contralateral efferent gain control to the cochlea.

PubMed

Bidelman, Gavin M; Schneider, Amy D; Heitzmann, Victoria R; Bhagat, Shaum P

2017-02-01

Human hearing sensitivity is easily compromised with overexposure to excessively loud sounds, leading to permanent hearing damage. Consequently, finding activities and/or experiential factors that distinguish "tender" from "tough" ears (i.e., acoustic vulnerability) would be important for identifying people at higher risk for hearing damage. To regulate sound transmission and protect the inner ear against acoustic trauma, the auditory system modulates gain control to the cochlea via biological feedback of the medial olivocochlear (MOC) efferents, a neuronal pathway linking the lower brainstem and cochlear outer hair cells. We hypothesized that a salient form of auditory experience shown to have pervasive neuroplastic benefits, namely musical training, might act to fortify hearing through tonic engagement of these reflexive pathways. By measuring MOC efferent feedback via otoacoustic emissions (cochlear emitted sounds), we show that dynamic ipsilateral and contralateral cochlear gain control is enhanced in musically-trained individuals. Across all participants, MOC strength was correlated with the years of listeners' training suggested that efferent gain control is experience dependent. Our data provide new evidence that intensive listening experience(s) (e.g., musicianship) can strengthen the ipsi/contralateral MOC efferent system and sound regulation to the inner ear. Implications for reducing acoustic vulnerability to damaging sounds are discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

Application of variable-gain output feedback for high-alpha control

NASA Technical Reports Server (NTRS)

Ostroff, Aaron J.

1990-01-01

A variable-gain, optimal, discrete, output feedback design approach that is applied to a nonlinear flight regime is described. The flight regime covers a wide angle-of-attack range that includes stall and post stall. The paper includes brief descriptions of the variable-gain formulation, the discrete-control structure and flight equations used to apply the design approach, and the high performance airplane model used in the application. Both linear and nonlinear analysis are shown for a longitudinal four-model design case with angles of attack of 5, 15, 35, and 60 deg. Linear and nonlinear simulations are compared for a single-point longitudinal design at 60 deg angle of attack. Nonlinear simulations for the four-model, multi-mode, variable-gain design include a longitudinal pitch-up and pitch-down maneuver and high angle-of-attack regulation during a lateral maneuver.

A Presynaptic Gain Control Mechanism Fine-Tunes Olfactory Behavior

PubMed Central

Root, Cory M.; Masuyama, Kaoru; Green, David S.; Enell, Lina E.; Nässel, Dick R.; Lee, Chi-Hon; Wang, Jing W.

2008-01-01

Early sensory processing can play a critical role in sensing environmental cues. We have investigated the physiological and behavioral function of gain control at the first synapse of olfactory processing in Drosophila. We report that olfactory receptor neurons (ORNs) express the GABAB receptor (GABABR) and its expression expands the dynamic range of ORN synaptic transmission that is preserved in projection neuron responses. Strikingly, we find that different ORN channels have unique baseline levels of GABABR expression. ORNs that sense the aversive odorant CO2 do not express GABABRs nor exhibit any presynaptic inhibition. In contrast, pheromone-sensing ORNs express a high level of GABABRs and exhibit strong presynaptic inhibition. Furthermore, a behavioral significance of presynaptic inhibition was revealed by a courtship behavior in which pheromone-dependent mate localization is impaired in flies that lack GABABRs in specific ORNs. Together, these findings indicate that different olfactory receptor channels may employ heterogeneous presynaptic gain control as a mechanism to allow an animal’s innate behavioral responses to match its ecological needs. PMID:18667158

NASA Schedule Management Handbook

NASA Technical Reports Server (NTRS)

2011-01-01

The purpose of schedule management is to provide the framework for time-phasing, resource planning, coordination, and communicating the necessary tasks within a work effort. The intent is to improve schedule management by providing recommended concepts, processes, and techniques used within the Agency and private industry. The intended function of this handbook is two-fold: first, to provide guidance for meeting the scheduling requirements contained in NPR 7120.5, NASA Space Flight Program and Project Management Requirements, NPR 7120.7, NASA Information Technology and Institutional Infrastructure Program and Project Requirements, NPR 7120.8, NASA Research and Technology Program and Project Management Requirements, and NPD 1000.5, Policy for NASA Acquisition. The second function is to describe the schedule management approach and the recommended best practices for carrying out this project control function. With regards to the above project management requirements documents, it should be noted that those space flight projects previously established and approved under the guidance of prior versions of NPR 7120.5 will continue to comply with those requirements until project completion has been achieved. This handbook will be updated as needed, to enhance efficient and effective schedule management across the Agency. It is acknowledged that most, if not all, external organizations participating in NASA programs/projects will have their own internal schedule management documents. Issues that arise from conflicting schedule guidance will be resolved on a case by case basis as contracts and partnering relationships are established. It is also acknowledged and understood that all projects are not the same and may require different levels of schedule visibility, scrutiny and control. Project type, value, and complexity are factors that typically dictate which schedule management practices should be employed.

Status Report on the Development of Micro-Scheduling Software for the Advanced Outage Control Center Project

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

Germain, Shawn St.; Thomas, Kenneth; Farris, Ronald

2014-09-01

The long-term viability of existing nuclear power plants (NPPs) in the United States (U.S.) is dependent upon a number of factors, including maintaining high capacity factors, maintaining nuclear safety, and reducing operating costs, particularly those associated with refueling outages. Refueling outages typically take 20-30 days, and for existing light water NPPs in the U.S., the reactor cannot be in operation during the outage. Furthermore, given that many NPPs generate between $1-1.5 million/day in revenue when in operation, there is considerable interest in shortening the length of refueling outages. Yet, refueling outages are highly complex operations, involving multiple concurrent and dependentmore » activities that are difficult to coordinate. Finding ways to improve refueling outage performance while maintaining nuclear safety has proven to be difficult. The Advanced Outage Control Center project is a research and development (R&D) demonstration activity under the Light Water Reactor Sustainability (LWRS) Program. LWRS is a R&D program which works with industry R&D programs to establish technical foundations for the licensing and managing of long-term, safe, and economical operation of current NPPs. The Advanced Outage Control Center project has the goal of improving the management of commercial NPP refueling outages. To accomplish this goal, this INL R&D project is developing an advanced outage control center (OCC) that is specifically designed to maximize the usefulness of communication and collaboration technologies for outage coordination and problem resolution activities. This report describes specific recent efforts to develop a capability called outage Micro-Scheduling. Micro-Scheduling is the ability to allocate and schedule outage support task resources on a sub-hour basis. Micro-Scheduling is the real-time fine-tuning of the outage schedule to react to the actual progress of the primary outage activities to ensure that support task resources are

Scheduling the future NASA Space Network: Experiences with a flexible scheduling prototype

NASA Technical Reports Server (NTRS)

Happell, Nadine; Moe, Karen L.; Minnix, Jay

1993-01-01

NASA's Space Network (SN) provides telecommunications and tracking services to low earth orbiting spacecraft. One proposal for improving resource allocation and automating conflict resolution for the SN is the concept of flexible scheduling. In this concept, each Payload Operations Control Center (POCC) will possess a Space Network User POCC Interface (SNUPI) to support the development and management of flexible requests. Flexible requests express the flexibility, constraints, and repetitious nature of the user's communications requirements. Flexible scheduling is expected to improve SN resource utilization and user satisfaction, as well as reduce the effort to produce and maintain a schedule. A prototype testbed has been developed to better understand flexible scheduling as it applies to the SN. This testbed consists of a SNUPI workstation, an SN scheduler, and a flexible request language that conveys information between the two systems. All three are being evaluated by operations personnel. Benchmark testing is being conducted on the scheduler to quantify the productivity improvements achieved with flexible requests.

Digitally gain controlled linear high voltage amplifier for laboratory applications.

PubMed

Koçum, C

2011-08-01

The design of a digitally gain controlled high-voltage non-inverting bipolar linear amplifier is presented. This cost efficient and relatively simple circuit has stable operation range from dc to 90 kHz under the load of 10 kΩ and 39 pF. The amplifier can swing up to 360 V(pp) under these conditions and it has 2.5 μs rise time. The gain can be changed by the aid of JFETs. The amplifiers have been realized using a combination of operational amplifiers and high-voltage discrete bipolar junction transistors. The circuit details and performance characteristics are discussed.

Adaptive fuzzy dynamic surface control for the chaotic permanent magnet synchronous motor using Nussbaum gain

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

Luo, Shaohua

This paper is concerned with the problem of adaptive fuzzy dynamic surface control (DSC) for the permanent magnet synchronous motor (PMSM) system with chaotic behavior, disturbance and unknown control gain and parameters. Nussbaum gain is adopted to cope with the situation that the control gain is unknown. And the unknown items can be estimated by fuzzy logic system. The proposed controller guarantees that all the signals in the closed-loop system are bounded and the system output eventually converges to a small neighborhood of the desired reference signal. Finally, the numerical simulations indicate that the proposed scheme can suppress the chaosmore » of PMSM and show the effectiveness and robustness of the proposed method.« less

Adaptive fuzzy dynamic surface control for the chaotic permanent magnet synchronous motor using Nussbaum gain.

PubMed

Luo, Shaohua

2014-09-01

This paper is concerned with the problem of adaptive fuzzy dynamic surface control (DSC) for the permanent magnet synchronous motor (PMSM) system with chaotic behavior, disturbance and unknown control gain and parameters. Nussbaum gain is adopted to cope with the situation that the control gain is unknown. And the unknown items can be estimated by fuzzy logic system. The proposed controller guarantees that all the signals in the closed-loop system are bounded and the system output eventually converges to a small neighborhood of the desired reference signal. Finally, the numerical simulations indicate that the proposed scheme can suppress the chaos of PMSM and show the effectiveness and robustness of the proposed method.

40 CFR Appendix K to Subpart A of... - Commodity Codes From the Harmonized Tariff Schedule for Controlled Substances and Used Controlled...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 18 2013-07-01 2013-07-01 false Commodity Codes From the Harmonized Tariff Schedule for Controlled Substances and Used Controlled Substances K Appendix K to Subpart A of...) PROTECTION OF STRATOSPHERIC OZONE Production and Consumption Controls Pt. 82, Subpt. A, App. K Appendix K to...

40 CFR Appendix K to Subpart A of... - Commodity Codes From the Harmonized Tariff Schedule for Controlled Substances and Used Controlled...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 17 2011-07-01 2011-07-01 false Commodity Codes From the Harmonized Tariff Schedule for Controlled Substances and Used Controlled Substances K Appendix K to Subpart A of...) PROTECTION OF STRATOSPHERIC OZONE Production and Consumption Controls Pt. 82, Subpt. A, App. K Appendix K to...

40 CFR Appendix K to Subpart A of... - Commodity Codes From the Harmonized Tariff Schedule for Controlled Substances and Used Controlled...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 18 2012-07-01 2012-07-01 false Commodity Codes From the Harmonized Tariff Schedule for Controlled Substances and Used Controlled Substances K Appendix K to Subpart A of...) PROTECTION OF STRATOSPHERIC OZONE Production and Consumption Controls Pt. 82, Subpt. A, App. K Appendix K to...

40 CFR Appendix K to Subpart A of... - Commodity Codes From the Harmonized Tariff Schedule for Controlled Substances and Used Controlled...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 18 2014-07-01 2014-07-01 false Commodity Codes From the Harmonized Tariff Schedule for Controlled Substances and Used Controlled Substances K Appendix K To Subpart A Of...) PROTECTION OF STRATOSPHERIC OZONE Production and Consumption Controls Pt. 82, Subpt. A, App. K Appendix K To...

40 CFR Appendix K to Subpart A of... - Commodity Codes From the Harmonized Tariff Schedule for Controlled Substances and Used Controlled...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Commodity Codes From the Harmonized Tariff Schedule for Controlled Substances and Used Controlled Substances K Appendix K to Subpart A of...) PROTECTION OF STRATOSPHERIC OZONE Production and Consumption Controls Pt. 82, Subpt. A, App. K Appendix K to...

75 FR 15642 - Schedules of Controlled Substances: Exempted Prescription Product; River Edge Pharmaceutical...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-30

... 1117-AB28 Schedules of Controlled Substances: Exempted Prescription Product; River Edge Pharmaceutical... new applications for exemption. DEA has received one new application for exemption for River Edge... application for exemption pursuant to the provisions of 21 CFR 1308.32 for: River Edge Pharmaceutical's...

Missed deadline notification in best-effort schedulers

NASA Astrophysics Data System (ADS)

Banachowski, Scott A.; Wu, Joel; Brandt, Scott A.

2003-12-01

It is common to run multimedia and other periodic, soft real-time applications on general-purpose computer systems. These systems use best-effort scheduling algorithms that cannot guarantee applications will receive responsive scheduling to meet deadline or timing requirements. We present a simple mechanism called Missed Deadline Notification (MDN) that allows applications to notify the system when they do not receive their desired level of responsiveness. Consisting of a single system call with no arguments, this simple interface allows the operating system to provide better support for soft real-time applications without any a priori information about their timing or resource needs. We implemented MDN in three different schedulers: Linux, BEST, and BeRate. We describe these implementations and their performance when running real-time applications and discuss policies to prevent applications from abusing MDN to gain extra resources.

A study of interactive control scheduling and economic assessment for robotic systems

NASA Technical Reports Server (NTRS)

1982-01-01

A class of interactive control systems is derived by generalizing interactive manipulator control systems. Tasks of interactive control systems can be represented as a network of a finite set of actions which have specific operational characteristics and specific resource requirements, and which are of limited duration. This has enabled the decomposition of the overall control algorithm simultaneously and asynchronously. The performance benefits of sensor referenced and computer-aided control of manipulators in a complex environment is evaluated. The first phase of the CURV arm control system software development and the basic features of the control algorithms and their software implementation are presented. An optimal solution for a production scheduling problem that will be easy to implement in practical situations is investigated.

Electromagnetic interference-aware transmission scheduling and power control for dynamic wireless access in hospital environments.

PubMed

Phunchongharn, Phond; Hossain, Ekram; Camorlinga, Sergio

2011-11-01

We study the multiple access problem for e-Health applications (referred to as secondary users) coexisting with medical devices (referred to as primary or protected users) in a hospital environment. In particular, we focus on transmission scheduling and power control of secondary users in multiple spatial reuse time-division multiple access (STDMA) networks. The objective is to maximize the spectrum utilization of secondary users and minimize their power consumption subject to the electromagnetic interference (EMI) constraints for active and passive medical devices and minimum throughput guarantee for secondary users. The multiple access problem is formulated as a dual objective optimization problem which is shown to be NP-complete. We propose a joint scheduling and power control algorithm based on a greedy approach to solve the problem with much lower computational complexity. To this end, an enhanced greedy algorithm is proposed to improve the performance of the greedy algorithm by finding the optimal sequence of secondary users for scheduling. Using extensive simulations, the tradeoff in performance in terms of spectrum utilization, energy consumption, and computational complexity is evaluated for both the algorithms.

How should periods without social interaction be scheduled? Children's preference for practical schedules of positive reinforcement.

PubMed

Luczynski, Kevin C; Hanley, Gregory P

2014-01-01

Several studies have shown that children prefer contingent reinforcement (CR) rather than yoked noncontingent reinforcement (NCR) when continuous reinforcement is programmed in the CR schedule. Preference has not, however, been evaluated for practical schedules that involve CR. In Study 1, we assessed 5 children's preference for obtaining social interaction via a multiple schedule (periods of fixed-ratio 1 reinforcement alternating with periods of extinction), a briefly signaled delayed reinforcement schedule, and an NCR schedule. The multiple schedule promoted the most efficient level of responding. In general, children chose to experience the multiple schedule and avoided the delay and NCR schedules, indicating that they preferred multiple schedules as the means to arrange practical schedules of social interaction. In Study 2, we evaluated potential controlling variables that influenced 1 child's preference for the multiple schedule and found that the strong positive contingency was the primary variable. © Society for the Experimental Analysis of Behavior.

Scenario-based, closed-loop model predictive control with application to emergency vehicle scheduling

NASA Astrophysics Data System (ADS)

Goodwin, Graham. C.; Medioli, Adrian. M.

2013-08-01

Model predictive control has been a major success story in process control. More recently, the methodology has been used in other contexts, including automotive engine control, power electronics and telecommunications. Most applications focus on set-point tracking and use single-sequence optimisation. Here we consider an alternative class of problems motivated by the scheduling of emergency vehicles. Here disturbances are the dominant feature. We develop a novel closed-loop model predictive control strategy aimed at this class of problems. We motivate, and illustrate, the ideas via the problem of fluid deployment of ambulance resources.

Scheduling Observations of Celestial Objects for Earth Observing Sensor Calibration

NASA Technical Reports Server (NTRS)

Wilson, Truman; Xiong, Xiaoxiong

2016-01-01

Radiometric calibration of Earth-observing satellite sensors is critical for tracking on-orbit gain changes through- out the satellite's mission. The Moon, being a stable, well-characterized radiometric target, has been used effectively for tracking the relative gain changes of the reflective solar bands for the Moderate Resolution Imaging Spectroradiometer (MODIS) on board EOS AM-1 (Terra) and PM-1 (Aqua). The Moon is viewed through the MODIS space-view port, and the relative phase of the Moon is restricted to within 0.5 degrees of a chosen target phase to increase the accuracy of the calibration. These geometric restrictions require spacecraft maneuvers in order to bring space-view port into proper alignment with the position of the Moon when the phase requirement is met. In this paper, we describe a versatile tool for scheduling such maneuvers based on the required geometry and lunar phase restrictions for a general spacecraft bound instrument. The results of the scheduling tool have been verified using lunar images from Aqua and Terra MODIS after a scheduled roll maneuver was performed. This tool has also been tested for the Visible Infrared Imaging Radiometer Suite (VIIRS) and the Advanced Technology Microwave Sounder on-board the Suomi-NPP spacecraft. As an extension of this work, we have also developed a tool for scheduling views of bright stars. These stars provide another well-characterized radiometric source that can be used for sensor calibration. This tool has been implemented to determine the times in which a chosen star can be viewed by the high gain stages of the day/night band for the VIIRS instrument.

76 FR 11566 - Proposed Collection; Comment Request for Form 1065-B and Schedules

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-02

... comments concerning Form 1065-B, U.S. Return of Income for Electing Large Partnerships, and Schedule K-1... information return used to report the income, gains, losses, deductions, etc., from the operation of an... income tax returns. Current Actions: Schedule K and M-3 have been added to this collection which has...

Automatic Scheduling and Planning (ASAP) in future ground control systems

NASA Technical Reports Server (NTRS)

Matlin, Sam

1988-01-01

This report describes two complementary approaches to the problem of space mission planning and scheduling. The first is an Expert System or Knowledge-Based System for automatically resolving most of the activity conflicts in a candidate plan. The second is an Interactive Graphics Decision Aid to assist the operator in manually resolving the residual conflicts which are beyond the scope of the Expert System. The two system designs are consistent with future ground control station activity requirements, support activity timing constraints, resource limits and activity priority guidelines.

Parametric instabilities and their control in multidimensional nonuniform gain media

NASA Astrophysics Data System (ADS)

Charbonneau-Lefort, Mathieu; Afeyan, Bedros; Fejer, Martin

2007-11-01

In order to control parametric instabilities in large scale long pulse laser produced plasmas, optical mixing techniques seem most promising [1]. We examine ways of controlling the growth of some modes while creating other unstable ones in nonuniform gain media, including the effects of transverse localization of the pump wave. We show that multidimensional effects are essential to understand laser-gain medium interactions [2] and that one dimensional models such as the celebrated Rosenbluth result [3] can be misleading [4]. These findings are verified in experiments carried out in a chirped quasi-phase-matched gratings in optical parametric amplifiers where thousands of shots can be taken and statistically significant and stable results obtained. [1] B. Afeyan, et al., IFSA Proceedings, 2003. [2] M. M. Sushchik and G. I. Freidman, Radiofizika 13, 1354 (1970). [3] M. N. Rosenbluth, Phys. Rev. Lett. 29, 565 (1972). [4] M. Charbonneau-Lefort, PhD thesis, Stanford University, 2007.

Reward value-based gain control: divisive normalization in parietal cortex.

PubMed

Louie, Kenway; Grattan, Lauren E; Glimcher, Paul W

2011-07-20

The representation of value is a critical component of decision making. Rational choice theory assumes that options are assigned absolute values, independent of the value or existence of other alternatives. However, context-dependent choice behavior in both animals and humans violates this assumption, suggesting that biological decision processes rely on comparative evaluation. Here we show that neurons in the monkey lateral intraparietal cortex encode a relative form of saccadic value, explicitly dependent on the values of the other available alternatives. Analogous to extra-classical receptive field effects in visual cortex, this relative representation incorporates target values outside the response field and is observed in both stimulus-driven activity and baseline firing rates. This context-dependent modulation is precisely described by divisive normalization, indicating that this standard form of sensory gain control may be a general mechanism of cortical computation. Such normalization in decision circuits effectively implements an adaptive gain control for value coding and provides a possible mechanistic basis for behavioral context-dependent violations of rationality.

Gain control by layer six in cortical circuits of vision.

PubMed

Olsen, Shawn R; Bortone, Dante S; Adesnik, Hillel; Scanziani, Massimo

2012-02-22

After entering the cerebral cortex, sensory information spreads through six different horizontal neuronal layers that are interconnected by vertical axonal projections. It is believed that through these projections layers can influence each other's response to sensory stimuli, but the specific role that each layer has in cortical processing is still poorly understood. Here we show that layer six in the primary visual cortex of the mouse has a crucial role in controlling the gain of visually evoked activity in neurons of the upper layers without changing their tuning to orientation. This gain modulation results from the coordinated action of layer six intracortical projections to superficial layers and deep projections to the thalamus, with a substantial role of the intracortical circuit. This study establishes layer six as a major mediator of cortical gain modulation and suggests that it could be a node through which convergent inputs from several brain areas can regulate the earliest steps of cortical visual processing.

A Conceptual Level Design for a Static Scheduler for Hard Real-Time Systems

DTIC Science & Technology

1988-03-01

The design of hard real - time systems is gaining a great deal of attention in the software engineering field as more and more real-world processes are...for these hard real - time systems . PSDL, as an executable design language, is supported by an execution support system consisting of a static scheduler, dynamic scheduler, and translator.

Presynaptic gain control by endogenous cotransmission of dopamine and GABA in the olfactory bulb.

PubMed

Vaaga, Christopher E; Yorgason, Jordan T; Williams, John T; Westbrook, Gary L

2017-03-01

In the olfactory bulb, lateral inhibition mediated by local juxtaglomerular interneurons has been proposed as a gain control mechanism, important for decorrelating odorant responses. Among juxtaglomerular interneurons, short axon cells are unique as dual-transmitter neurons that release dopamine and GABA. To examine their intraglomerular function, we expressed channelrhodopsin under control of the DAT-cre promoter and activated olfactory afferents within individual glomeruli. Optical stimulation of labeled cells triggered endogenous dopamine release as measured by cyclic voltammetry and GABA release as measured by whole cell GABA A receptor currents. Activation of short axon cells reduced the afferent presynaptic release probability via D 2 and GABA B receptor activation, resulting in reduced spiking in both mitral and external tufted cells. Our results suggest that short axon cells influence glomerular activity not only by direct inhibition of external tufted cells but also by inhibition of afferent inputs to external tufted and mitral cells. NEW & NOTEWORTHY Sensory systems, including the olfactory system, encode information across a large dynamic range, making synaptic mechanisms of gain control critical to proper function. Here we demonstrate that a dual-transmitter interneuron in the olfactory bulb controls the gain of intraglomerular afferent input via two distinct mechanisms, presynaptic inhibition as well as inhibition of a principal neuron subtype, and thereby potently controls the synaptic gain of afferent inputs. Copyright © 2017 the American Physiological Society.

A new adjustable gains for second order sliding mode control of saturated DFIG-based wind turbine

NASA Astrophysics Data System (ADS)

Bounadja, E.; Djahbar, A.; Taleb, R.; Boudjema, Z.

2017-02-01

The control of Doubly-Fed induction generator (DFIG), used in wind energy conversion, has been given a great deal of interest. Frequently, this control has been dealt with ignoring the magnetic saturation effect in the DFIG model. The aim of the present work is twofold: firstly, the magnetic saturation effect is accounted in the control design model; secondly, a new second order sliding mode control scheme using adjustable-gains (AG-SOSMC) is proposed to control the DFIG via its rotor side converter. This scheme allows the independent control of the generated active and reactive power. Conventionally, the second order sliding mode control (SOSMC) applied to the DFIG, utilize the super-twisting algorithm with fixed gains. In the proposed AG-SOSMC, a simple means by which the controller can adjust its behavior is used. For that, a linear function is used to represent the variation in gain as a function of the absolute value of the discrepancy between the reference rotor current and its measured value. The transient DFIG speed response using the aforementioned characteristic is compared with the one determined by using the conventional SOSMC controller with fixed gains. Simulation results show, accurate dynamic performances, quicker transient response and more accurate control are achieved for different operating conditions.

Some effects of 8- vs 10-hour work schedules on the test performance/alertness of air traffic control specialists.

DOT National Transportation Integrated Search

1995-12-01

A 10-hour, 4-day rotating shift schedule worked by some Air Traffic Control Specialists (ATCSs) was compared to the more traditional 8-hour, 2-2-1 rapidly rotating schedule. Measures of performance and alertness were obtained from a group of 52 ATCSs...

Knowledge-based scheduling of arrival aircraft

NASA Technical Reports Server (NTRS)

Krzeczowski, K.; Davis, T.; Erzberger, H.; Lev-Ram, I.; Bergh, C.

1995-01-01

A knowledge-based method for scheduling arrival aircraft in the terminal area has been implemented and tested in real-time simulation. The scheduling system automatically sequences, assigns landing times, and assigns runways to arrival aircraft by utilizing continuous updates of aircraft radar data and controller inputs. The scheduling algorithms is driven by a knowledge base which was obtained in over two thousand hours of controller-in-the-loop real-time simulation. The knowledge base contains a series of hierarchical 'rules' and decision logic that examines both performance criteria, such as delay reduction, as well as workload reduction criteria, such as conflict avoidance. The objective of the algorithms is to devise an efficient plan to land the aircraft in a manner acceptable to the air traffic controllers. This paper will describe the scheduling algorithms, give examples of their use, and present data regarding their potential benefits to the air traffic system.

Neuro-adaptive backstepping control of SISO non-affine systems with unknown gain sign.

PubMed

Ramezani, Zahra; Arefi, Mohammad Mehdi; Zargarzadeh, Hassan; Jahed-Motlagh, Mohammad Reza

2016-11-01

This paper presents two neuro-adaptive controllers for a class of uncertain single-input, single-output (SISO) nonlinear non-affine systems with unknown gain sign. The first approach is state feedback controller, so that a neuro-adaptive state-feedback controller is constructed based on the backstepping technique. The second approach is an observer-based controller and K-filters are designed to estimate the system states. The proposed method relaxes a priori knowledge of control gain sign and therefore by utilizing the Nussbaum-type functions this problem is addressed. In these methods, neural networks are employed to approximate the unknown nonlinear functions. The proposed adaptive control schemes guarantee that all the closed-loop signals are semi-globally uniformly ultimately bounded (SGUUB). Finally, the theoretical results are numerically verified through simulation examples. Simulation results show the effectiveness of the proposed methods. Copyright © 2016 ISA. All rights reserved.

The effects of control-display gain on performance of race car drivers in an isometric braking task.

PubMed

de Winter, J C F; de Groot, S

2012-12-01

To minimise lap times during car racing, it is important to build up brake forces rapidly and maintain precise control. We examined the effect of the amplification factor (gain) between brake pedal force and a visually represented output value on a driver's ability to track a target value. The test setup was a formula racing car cockpit fitted with an isometric brake pedal. Thirteen racing drivers performed tracking tasks with four control-display gains and two target functions: a step function (35 trials per gain) and a multisine function (15 trials per gain). The control-display gain had only minor effects on root mean-squared error between output value and target value, but it had large effects on build-up speed, overshoot, within-participants variability, and self-reported physical load. The results confirm the hypothesis that choosing an optimum gain involves balancing stability against physical effort.

Improving Resource Selection and Scheduling Using Predictions. Chapter 1

NASA Technical Reports Server (NTRS)

Smith, Warren

2003-01-01

The introduction of computational grids has resulted in several new problems in the area of scheduling that can be addressed using predictions. The first problem is selecting where to run an application on the many resources available in a grid. Our approach to help address this problem is to provide predictions of when an application would start to execute if submitted to specific scheduled computer systems. The second problem is gaining simultaneous access to multiple computer systems so that distributed applications can be executed. We help address this problem by investigating how to support advance reservations in local scheduling systems. Our approaches to both of these problems are based on predictions for the execution time of applications on space- shared parallel computers. As a side effect of this work, we also discuss how predictions of application run times can be used to improve scheduling performance.

Adaptive attitude control and momentum management for large-angle spacecraft maneuvers

NASA Technical Reports Server (NTRS)

Parlos, Alexander G.; Sunkel, John W.

1992-01-01

The fully coupled equations of motion are systematically linearized around an equilibrium point of a gravity gradient stabilized spacecraft, controlled by momentum exchange devices. These equations are then used for attitude control system design of an early Space Station Freedom flight configuration, demonstrating the errors caused by the improper approximation of the spacecraft dynamics. A full state feedback controller, incorporating gain-scheduled adaptation of the attitude gains, is developed for use during spacecraft on-orbit assembly or operations characterized by significant mass properties variations. The feasibility of the gain adaptation is demonstrated via a Space Station Freedom assembly sequence case study. The attitude controller stability robustness and transient performance during gain adaptation appear satisfactory.

Second-order schedules of token reinforcement with pigeons: effects of fixed- and variable-ratio exchange schedules.

PubMed

Foster, T A; Hackenberg, T D; Vaidya, M

2001-09-01

Pigeons' key pecks produced food under second-order schedules of token reinforcement, with light-emitting diodes serving as token reinforcers. In Experiment 1, tokens were earned according to a fixed-ratio 50 schedule and were exchanged for food according to either fixed-ratio or variable-ratio exchange schedules, with schedule type varied across conditions. In Experiment 2, schedule type was varied within sessions using a multiple schedule. In one component, tokens were earned according to a fixed-ratio 50 schedule and exchanged according to a variable-ratio schedule. In the other component, tokens were earned according to a variable-ratio 50 schedule and exchanged according to a fixed-ratio schedule. In both experiments, the number of responses per exchange was varied parametrically across conditions, ranging from 50 to 400 responses. Response rates decreased systematically with increases in the fixed-ratio exchange schedules, but were much less affected by changes in the variable-ratio exchange schedules. Response rates were consistently higher under variable-ratio exchange schedules than tinder comparable fixed-ratio exchange schedules, especially at higher exchange ratios. These response-rate differences were due both to greater pre-ratio pausing and to lower local rates tinder the fixed-ratio exchange schedules. Local response rates increased with proximity to food under the higher fixed-ratio exchange schedules, indicative of discriminative control by the tokens.

75 FR 13678 - Schedules of Controlled Substances; Table of Excluded Nonnarcotic Products: Nasal Decongestant...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-23

... 1117-AB23 Schedules of Controlled Substances; Table of Excluded Nonnarcotic Products: Nasal Decongestant Inhalers Manufactured by Classic Pharmaceuticals, LLC AGENCY: Drug Enforcement Administration (DEA... Administration (DEA) is updating the Table of Excluded Nonnarcotic Products found in 21 CFR 1308.22 to include...

Association between subthalamic nucleus deep brain stimulation and weight gain: Results of a case-control study.

PubMed

Strowd, Roy E; Herco, Maja; Passmore-Griffin, Leah; Avery, Bradley; Haq, Ihtsham; Tatter, Stephen B; Tate, Jessica; Siddiqui, Mustafa S

2016-01-01

To evaluate whether weight change in patients with Parkinson's disease (PD) is different in those undergoing deep brain stimulation (DBS) of the subthalamic nucleus (STN) compared to those not undergoing DBS. A retrospective case-control study was performed in PD patients who had undergone STN DBS (cases) compared to matched PD patients without DBS (controls). Demographic and clinical data including Unified Parkinson's Disease Rating Scale (UPDRS) motor scores were collected. Repeated measures mixed model regression was used to identify variables associated with weight gain. Thirty-five cases and 34 controls were identified. Baseline age, gender, diagnosis and weight were similar. Duration of diagnosis was longer in cases (6.3 vs 4.9 years, p=0.0015). At 21.3 months, cases gained 2.9 kg (+4.65%) while controls lost 1.8 kg (-3.05%, p<0.02). Postoperative UPDRS motor scores improved by 49% indicating surgical efficacy. Only younger age (p=0.0002) and DBS (p=0.008) were significantly associated with weight gain. In this case-control study, PD patients undergoing STN DBS experienced post-operative weight gain that was significantly different from the weight loss observed in non-DBS PD controls. Patients, especially overweight individuals, should be informed that STN DBS can result in weight gain. Copyright © 2015 Elsevier B.V. All rights reserved.

Integrated resource scheduling in a distributed scheduling environment

NASA Technical Reports Server (NTRS)

Zoch, David; Hall, Gardiner

1988-01-01

The Space Station era presents a highly-complex multi-mission planning and scheduling environment exercised over a highly distributed system. In order to automate the scheduling process, customers require a mechanism for communicating their scheduling requirements to NASA. A request language that a remotely-located customer can use to specify his scheduling requirements to a NASA scheduler, thus automating the customer-scheduler interface, is described. This notation, Flexible Envelope-Request Notation (FERN), allows the user to completely specify his scheduling requirements such as resource usage, temporal constraints, and scheduling preferences and options. The FERN also contains mechanisms for representing schedule and resource availability information, which are used in the inter-scheduler inconsistency resolution process. Additionally, a scheduler is described that can accept these requests, process them, generate schedules, and return schedule and resource availability information to the requester. The Request-Oriented Scheduling Engine (ROSE) was designed to function either as an independent scheduler or as a scheduling element in a network of schedulers. When used in a network of schedulers, each ROSE communicates schedule and resource usage information to other schedulers via the FERN notation, enabling inconsistencies to be resolved between schedulers. Individual ROSE schedules are created by viewing the problem as a constraint satisfaction problem with a heuristically guided search strategy.

A hierarchical scheduling and management solution for dynamic reconfiguration in FPGA-based embedded systems

NASA Astrophysics Data System (ADS)

Cervero, T.; Gómez, A.; López, S.; Sarmiento, R.; Dondo, J.; Rincón, F.; López, J. C.

2013-05-01

One of the limiting factors that have prevented a widely dissemination of the reconfigurable technology is the absence of an appropriate model for certain target applications capable of offering a reliable control. Moreover, the lack of flexible and easy-to-use scheduling and management systems are also relevant drawbacks to be considered. Under static scenarios, it is relatively easy to schedule and manage the reconfiguration process since all the variations corresponding to predetermined and well-known tasks. However, the difficulty increases when the adaptation needs of the overall system change semi-randomly according to the environmental fluctuations. In this context, this work proposes a change in the paradigm of dynamically reconfigurable systems, by attending to the dynamically reconfigurable control problematic as a whole, in which the scheduling and the placement issues are packed together as a hierarchical management structure, interacting together as one entity from the system point of view, but performing their tasks with certain degree of independence each other. In this sense, the top hierarchical level corresponds with a dynamic scheduler in charge of planning and adjusting all the reconfigurable modules according to the variations of the external stimulus. The lower level interacts with the physical layer of the device by means of instantiating, relocating, removing a reconfigurable module following the scheduler's instructions. In regards to how fast is the proposed solution, the total partial reconfiguration time achieved with this proposal has been measured and compared with other two approaches: 1) using traditional Xilinx's tools; 2) using an optimized version of the Xilinx's drivers. The collected numbers demonstrate that our solution reaches a gain up to 10 times faster than the other approaches.

78 FR 17895 - Schedules of Controlled Substances: Placement of Alfaxalone into Schedule IV

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-25

... (Schedule IV under consideration), and midazolam. Since alfaxalone is a new veterinary product and has not...[alpha]-ol-11, 20-dione. Alfaxalone has a molecular formula of C 21 H 32 O 3 and a molecular weight of...

Discrimination of Variable Schedules Is Controlled by Interresponse Times Proximal to Reinforcement

ERIC Educational Resources Information Center

Tanno, Takayuki; Silberberg, Alan; Sakagami, Takayuki

2012-01-01

In Experiment 1, food-deprived rats responded to one of two schedules that were, with equal probability, associated with a sample lever. One schedule was always variable ratio, while the other schedule, depending on the trial within a session, was: (a) a variable-interval schedule; (b) a tandem variable-interval,…

Non preemptive soft real time scheduler: High deadline meeting rate on overload

NASA Astrophysics Data System (ADS)

Khalib, Zahereel Ishwar Abdul; Ahmad, R. Badlishah; El-Shaikh, Mohamed

2015-05-01

While preemptive scheduling has gain more attention among researchers, current work in non preemptive scheduling had shown promising result in soft real time jobs scheduling. In this paper we present a non preemptive scheduling algorithm meant for soft real time applications, which is capable of producing better performance during overload while maintaining excellent performance during normal load. The approach taken by this algorithm has shown more promising results compared to other algorithms including its immediate predecessor. We will present the analysis made prior to inception of the algorithm as well as simulation results comparing our algorithm named gutEDF with EDF and gEDF. We are convinced that grouping jobs utilizing pure dynamic parameters would produce better performance.

Scheduling Dependent Real-Time Activities

DTIC Science & Technology

1990-08-01

dependency relationships in a way that is suitable for all real - time systems . This thesis provides an algorithm, called DASA, that is effective for...scheduling the class of real - time systems known as supervisory control systems. Simulation experiments that account for the time required to make scheduling

Controlled mass pollination in loblolly pine to increase genetic gains

Treesearch

F.E. Bridgwater; D.L. Bramlett; T.D. Byram; W.J. Lowe

1998-01-01

Controlled mass pollination (CMP) is one way to increase genetic gains from traditional wind-pollinated seed orchards. Methodology is under development by several forestry companies in the southern USA. Costs of CMP depend on the efficient installation, pollination, and removal of inexpensive paper bags. Even in pilot-scale studies these costs seem reasonable. Net...

Job Scheduling Under the Portable Batch System

NASA Technical Reports Server (NTRS)

Henderson, Robert L.; Woodrow, Thomas S. (Technical Monitor)

1995-01-01

The typical batch queuing system schedules jobs for execution by a set of queue controls. The controls determine from which queues jobs may be selected. Within the queue, jobs are ordered first-in, first-run. This limits the set of scheduling policies available to a site. The Portable Batch System removes this limitation by providing an external scheduling module. This separate program has full knowledge of the available queued jobs, running jobs, and system resource usage. Sites are able to implement any policy expressible in one of several procedural language. Policies may range from "bet fit" to "fair share" to purely political. Scheduling decisions can be made over the full set of jobs regardless of queue or order. The scheduling policy can be changed to fit a wide variety of computing environments and scheduling goals. This is demonstrated by the use of PBS on an IBM SP-2 system at NASA Ames.

Controlling the gain contribution of background emitters in few-quantum-dot microlasers

NASA Astrophysics Data System (ADS)

Gericke, F.; Segnon, M.; von Helversen, M.; Hopfmann, C.; Heindel, T.; Schneider, C.; Höfling, S.; Kamp, M.; Musiał, A.; Porte, X.; Gies, C.; Reitzenstein, S.

2018-02-01

We provide experimental and theoretical insight into single-emitter lasing effects in a quantum dot (QD)-microlaser under controlled variation of background gain provided by off-resonant discrete gain centers. For that purpose, we apply an advanced two-color excitation concept where the background gain contribution of off-resonant QDs can be continuously tuned by precisely balancing the relative excitation power of two lasers emitting at different wavelengths. In this way, by selectively exciting a single resonant QD and off-resonant QDs, we identify distinct single-QD signatures in the lasing characteristics and distinguish between gain contributions of a single resonant emitter and a countable number of off-resonant background emitters to the optical output of the microlaser. Our work addresses the important question whether single-QD lasing is feasible in experimentally accessible systems and shows that, for the investigated microlaser, the single-QD gain needs to be supported by the background gain contribution of off-resonant QDs to reach the transition to lasing. Interestingly, while a single QD cannot drive the investigated micropillar into lasing, its relative contribution to the emission can be as high as 70% and it dominates the statistics of emitted photons in the intermediate excitation regime below threshold.

Alternative Schedules: What, How, and to What End?

ERIC Educational Resources Information Center

Wasley, Patricia A.

1997-01-01

The principal of a traditional high school in upstate New York asked faculty to reexamine the school schedule. After considerable debate, teachers decided to rotate class time so that no one suffered the afterlunch slump or day's-end rowdiness in a single class. Having gained confidence, a permanent teacher committee has added time blocks and…

77 FR 46519 - Proposed Aggregate Production Quotas for Schedule I and II Controlled Substances and Proposed...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-03

... Production Quotas for Schedule I and II Controlled Substances and Proposed Assessment of Annual Needs for the... the Controlled Substances Act (CSA) and assessment of annual needs for the list I chemicals ephedrine... proposed 2013 aggregate production quotas and assessment of annual needs, DEA has taken into account the...

F-8C adaptive flight control extensions. [for maximum likelihood estimation

NASA Technical Reports Server (NTRS)

Stein, G.; Hartmann, G. L.

1977-01-01

An adaptive concept which combines gain-scheduled control laws with explicit maximum likelihood estimation (MLE) identification to provide the scheduling values is described. The MLE algorithm was improved by incorporating attitude data, estimating gust statistics for setting filter gains, and improving parameter tracking during changing flight conditions. A lateral MLE algorithm was designed to improve true air speed and angle of attack estimates during lateral maneuvers. Relationships between the pitch axis sensors inherent in the MLE design were examined and used for sensor failure detection. Design details and simulation performance are presented for each of the three areas investigated.

Anchorage Arrival Scheduling Under Off-Nominal Weather Conditions

NASA Technical Reports Server (NTRS)

Grabbe, Shon; Chan, William N.; Mukherjee, Avijit

2012-01-01

Weather can cause flight diversions, passenger delays, additional fuel consumption and schedule disruptions at any high volume airport. The impacts are particularly acute at the Ted Stevens Anchorage International Airport in Anchorage, Alaska due to its importance as a major international portal. To minimize the impacts due to weather, a multi-stage scheduling process is employed that is iteratively executed, as updated aircraft demand and/or airport capacity data become available. The strategic scheduling algorithm assigns speed adjustments for flights that originate outside of Anchorage Center to achieve the proper demand and capacity balance. Similarly, an internal departure-scheduling algorithm assigns ground holds for pre-departure flights that originate from within Anchorage Center. Tactical flight controls in the form of airborne holding are employed to reactively account for system uncertainties. Real-world scenarios that were derived from the January 16, 2012 Anchorage visibility observations and the January 12, 2012 Anchorage arrival schedule were used to test the initial implementation of the scheduling algorithm in fast-time simulation experiments. Although over 90% of the flights in the scenarios arrived at Anchorage without requiring any delay, pre-departure scheduling was the dominant form of control for Anchorage arrivals. Additionally, tactical scheduling was used extensively in conjunction with the pre-departure scheduling to reactively compensate for uncertainties in the arrival demand. For long-haul flights, the strategic scheduling algorithm performed best when the scheduling horizon was greater than 1,000 nmi. With these long scheduling horizons, it was possible to absorb between ten and 12 minutes of delay through speed control alone. Unfortunately, the use of tactical scheduling, which resulted in airborne holding, was found to increase as the strategic scheduling horizon increased because of the additional uncertainty in the arrival times

Switched-Observer-Based Adaptive Neural Control of MIMO Switched Nonlinear Systems With Unknown Control Gains.

PubMed

Long, Lijun; Zhao, Jun

2017-07-01

In this paper, the problem of adaptive neural output-feedback control is addressed for a class of multi-input multioutput (MIMO) switched uncertain nonlinear systems with unknown control gains. Neural networks (NNs) are used to approximate unknown nonlinear functions. In order to avoid the conservativeness caused by adoption of a common observer for all subsystems, an MIMO NN switched observer is designed to estimate unmeasurable states. A new switched observer-based adaptive neural control technique for the problem studied is then provided by exploiting the classical average dwell time (ADT) method and the backstepping method and the Nussbaum gain technique. It effectively handles the obstacle about the coexistence of multiple Nussbaum-type function terms, and improves the classical ADT method, since the exponential decline property of Lyapunov functions for individual subsystems is no longer satisfied. It is shown that the technique proposed is able to guarantee semiglobal uniformly ultimately boundedness of all the signals in the closed-loop system under a class of switching signals with ADT, and the tracking errors converge to a small neighborhood of the origin. The effectiveness of the approach proposed is illustrated by its application to a two inverted pendulum system.

Modeling lateral geniculate nucleus response with contrast gain control. Part 2: Analysis

PubMed Central

Cope, Davis; Blakeslee, Barbara; McCourt, Mark E.

2014-01-01

Cope, Blakeslee and McCourt (2013) proposed a class of models for LGN ON-cell behavior consisting of a linear response with divisive normalization by local stimulus contrast. Here we analyze a specific model with the linear response defined by a difference-of-Gaussians filter and a circular Gaussian for the gain pool weighting function. For sinusoidal grating stimuli, the parameter region for band-pass behavior of the linear response is determined, the gain control response is shown to act as a switch (changing from “off” to “on” with increasing spatial frequency), and it is shown that large gain pools stabilize the optimal spatial frequency of the total nonlinear response at a fixed value independent of contrast and stimulus magnitude. Under- and super-saturation as well as contrast saturation occur as typical effects of stimulus magnitude. For circular spot stimuli, it is shown that large gain pools stabilize the spot size that yields the maximum response. PMID:24562034

Design and control of a vertical takeoff and landing fixed-wing unmanned aerial vehicle

NASA Astrophysics Data System (ADS)

Malang, Yasir

With the goal of extending capabilities of multi-rotor unmanned aerial vehicles (UAVs) for wetland conservation missions, a novel hybrid aircraft design consisting of four tilting rotors and a fixed wing is designed and built. The tilting rotors and nonlinear aerodynamic effects introduce a control challenge for autonomous flight, and the research focus is to develop and validate an autonomous transition flight controller. The overall controller structure consists of separate cascaded Proportional Integral Derivative (PID) controllers whose gains are scheduled according to the rotors' tilt angle. A control mechanism effectiveness factor is used to mix the multi-rotor and fixed-wing control actuators during transition. A nonlinear flight dynamics model is created and transition stability is shown through MATLAB simulations, which proves gain-scheduled control is a good fit for tilt-rotor aircraft. Experiments carried out using the prototype UAV validate simulation results for VTOL and tilted-rotor flight.

A heuristic approach to incremental and reactive scheduling

NASA Technical Reports Server (NTRS)

Odubiyi, Jide B.; Zoch, David R.

1989-01-01

An heuristic approach to incremental and reactive scheduling is described. Incremental scheduling is the process of modifying an existing schedule if the initial schedule does not meet its stated initial goals. Reactive scheduling occurs in near real-time in response to changes in available resources or the occurrence of targets of opportunity. Only minor changes are made during both incremental and reactive scheduling because a goal of re-scheduling procedures is to minimally impact the schedule. The described heuristic search techniques, which are employed by the Request Oriented Scheduling Engine (ROSE), a prototype generic scheduler, efficiently approximate the cost of reaching a goal from a given state and effective mechanisms for controlling search.

33 CFR 401.58 - Pleasure craft scheduling.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Pleasure craft scheduling. 401.58... OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.58 Pleasure craft scheduling. (a) The transit of pleasure craft shall be scheduled by the traffic controller or the officer in...

The LSST OCS scheduler design

NASA Astrophysics Data System (ADS)

Delgado, Francisco; Schumacher, German

2014-08-01

The Large Synoptic Survey Telescope (LSST) is a complex system of systems with demanding performance and operational requirements. The nature of its scientific goals requires a special Observatory Control System (OCS) and particularly a very specialized automatic Scheduler. The OCS Scheduler is an autonomous software component that drives the survey, selecting the detailed sequence of visits in real time, taking into account multiple science programs, the current external and internal conditions, and the history of observations. We have developed a SysML model for the OCS Scheduler that fits coherently in the OCS and LSST integrated model. We have also developed a prototype of the Scheduler that implements the scheduling algorithms in the simulation environment provided by the Operations Simulator, where the environment and the observatory are modeled with real weather data and detailed kinematics parameters. This paper expands on the Scheduler architecture and the proposed algorithms to achieve the survey goals.

Advanced control of dissolved oxygen concentration in fed batch cultures during recombinant protein production.

PubMed

Kuprijanov, A; Gnoth, S; Simutis, R; Lübbert, A

2009-02-01

Design and experimental validation of advanced pO(2) controllers for fermentation processes operated in the fed-batch mode are described. In most situations, the presented controllers are able to keep the pO(2) in fermentations for recombinant protein productions exactly on the desired value. The controllers are based on the gain-scheduling approach to parameter-adaptive proportional-integral controllers. In order to cope with the most often appearing distortions, the basic gain-scheduling feedback controller was complemented with a feedforward control component. This feedforward/feedback controller significantly improved pO(2) control. By means of numerical simulations, the controller behavior was tested and its parameters were determined. Validation runs were performed with three Escherichia coli strains producing different recombinant proteins. It is finally shown that the new controller leads to significant improvements in the signal-to-noise ratio of other key process variables and, thus, to a higher process quality.

Fault tolerant control laws

NASA Technical Reports Server (NTRS)

Ly, U. L.; Ho, J. K.

1986-01-01

A systematic procedure for the synthesis of fault tolerant control laws to actuator failure has been presented. Two design methods were used to synthesize fault tolerant controllers: the conventional LQ design method and a direct feedback controller design method SANDY. The latter method is used primarily to streamline the full-state Q feedback design into a practical implementable output feedback controller structure. To achieve robustness to control actuator failure, the redundant surfaces are properly balanced according to their control effectiveness. A simple gain schedule based on the landing gear up/down logic involving only three gains was developed to handle three design flight conditions: Mach .25 and Mach .60 at 5000 ft and Mach .90 at 20,000 ft. The fault tolerant control law developed in this study provides good stability augmentation and performance for the relaxed static stability aircraft. The augmented aircraft responses are found to be invariant to the presence of a failure. Furthermore, single-loop stability margins of +6 dB in gain and +30 deg in phase were achieved along with -40 dB/decade rolloff at high frequency.

Motivation by potential gains and losses affects control processes via different mechanisms in the attentional network.

PubMed

Paschke, Lena M; Walter, Henrik; Steimke, Rosa; Ludwig, Vera U; Gaschler, Robert; Schubert, Torsten; Stelzel, Christine

2015-05-01

Attentional control in demanding cognitive tasks can be improved by manipulating the motivational state. Motivation to obtain gains and motivation to avoid losses both usually result in faster reaction times and stronger activation in relevant brain areas such as the prefrontal cortex, but little is known about differences in the underlying neurocognitive mechanisms of these types of motivation in an attentional control context. In the present functional magnetic resonance imaging (fMRI) study, we tested whether potential gain and loss as motivating incentives lead to overlapping or distinct neural effects in the attentional network, and whether one of these conditions is more effective than the other. A Flanker task with word stimuli as targets and distracters was performed by 115 healthy participants. Using a mixed blocked and event-related design allowed us to investigate transient and sustained motivation-related effects. Participants could either gain money (potential gain) or avoid losing money (potential loss) in different task blocks. Participants showed a congruency effect with increased reaction times for incongruent compared to congruent trials. Potential gain led to generally faster responses compared to the neutral condition and to stronger improvements than potential loss. Potential loss also led to shorter response times compared to the neutral condition, but participants improved mainly during incongruent and not during congruent trials. The event-related fMRI data revealed a main effect of congruency with increased activity in the left inferior frontal gyrus (IFG) and inferior frontal junction area (IFJ), the pre-supplementary motor area (pre-SMA), bilateral insula, intraparietal sulcus (IPS) and visual word form area (VWFA). While potential gain led to increased activity in a cluster of the IFJ and the VWFA only during incongruent trials, potential loss was linked to activity increases in these regions during incongruent and congruent trials. The

A new distributed systems scheduling algorithm: a swarm intelligence approach

NASA Astrophysics Data System (ADS)

Haghi Kashani, Mostafa; Sarvizadeh, Raheleh; Jameii, Mahdi

2011-12-01

The scheduling problem in distributed systems is known as an NP-complete problem, and methods based on heuristic or metaheuristic search have been proposed to obtain optimal and suboptimal solutions. The task scheduling is a key factor for distributed systems to gain better performance. In this paper, an efficient method based on memetic algorithm is developed to solve the problem of distributed systems scheduling. With regard to load balancing efficiently, Artificial Bee Colony (ABC) has been applied as local search in the proposed memetic algorithm. The proposed method has been compared to existing memetic-Based approach in which Learning Automata method has been used as local search. The results demonstrated that the proposed method outperform the above mentioned method in terms of communication cost.

Elearning approaches to prevent weight gain in young adults: A randomized controlled study.

PubMed

Nikolaou, Charoula Konstantia; Hankey, Catherine Ruth; Lean, Michael Ernest John

2015-12-01

Preventing obesity among young adults should be a preferred public health approach given the limited efficacy of treatment interventions. This study examined whether weight gain can be prevented by online approaches using two different behavioral models, one overtly directed at obesity and the other covertly. A three-group parallel randomized controlled intervention was conducted in 2012-2013; 20,975 young adults were allocated a priori to one control and two "treatment" groups. Two treatment groups were offered online courses over 19 weeks on (1) personal weight control ("Not the Ice Cream Van," NTICV) and, (2) political, environmental, and social issues around food ("Goddess Demetra," "GD"). Control group received no contact. The primary outcome was weight change over 40 weeks. Within-group 40-week weight changes were different between groups (P < 0.001): Control (n = 2,134): +2.0 kg (95% CI = 1.5, 2.3 kg); NTICV (n = 1,810): -1.0 kg (95% CI = -1.3, -0.5); and GD (n = 2,057): -1.35 kg (95% CI = -1.4 to -0.7). Relative risks for weight gain vs. NTICV = 0.13 kg (95% CI = 0.10, 0.15), P < 0.0001; GD = 0.07 kg (95% CI = 0.05, 0.10), P < 0.0001. Both interventions were associated with prevention of the weight gain observed among control subjects. This low-cost intervention could be widely transferable as one tool against the obesity epidemic. Outside the randomized controlled trial setting, it could be enhanced using supporting advertising and social media. © 2015 The Obesity Society.

21 CFR 1305.06 - Persons entitled to fill orders for Schedule I and II controlled substances.

Code of Federal Regulations, 2010 CFR

2010-04-01

... II controlled substances, whether on a DEA Form 222 or an electronic order, may be filled only by a person registered with DEA as a manufacturer or distributor of controlled substances listed in Schedule I... DEA to dispense the substances, or to export the substances, if he/she is discontinuing business or if...

21 CFR 1305.06 - Persons entitled to fill orders for Schedule I and II controlled substances.

Code of Federal Regulations, 2011 CFR

2011-04-01

... II controlled substances, whether on a DEA Form 222 or an electronic order, may be filled only by a person registered with DEA as a manufacturer or distributor of controlled substances listed in Schedule I... DEA to dispense the substances, or to export the substances, if he/she is discontinuing business or if...

Tunning PID controller using particle swarm optimization algorithm on automatic voltage regulator system

NASA Astrophysics Data System (ADS)

Aranza, M. F.; Kustija, J.; Trisno, B.; Hakim, D. L.

2016-04-01

PID Controller (Proportional Integral Derivative) was invented since 1910, but till today still is used in industries, even though there are many kind of modern controllers like fuzz controller and neural network controller are being developed. Performance of PID controller is depend on on Proportional Gain (Kp), Integral Gain (Ki) and Derivative Gain (Kd). These gains can be got by using method Ziegler-Nichols (ZN), gain-phase margin, Root Locus, Minimum Variance dan Gain Scheduling however these methods are not optimal to control systems that nonlinear and have high-orde, in addition, some methods relative hard. To solve those obstacles, particle swarm optimization (PSO) algorithm is proposed to get optimal Kp, Ki and Kd. PSO is proposed because PSO has convergent result and not require many iterations. On this research, PID controller is applied on AVR (Automatic Voltage Regulator). Based on result of analyzing transient, stability Root Locus and frequency response, performance of PID controller is better than Ziegler-Nichols.

Schedules of Controlled Substances: Placement of FDA-Approved Products of Oral Solutions Containing Dronabinol [(-)-delta-9-transtetrahydrocannabinol (delta-9-THC)] in Schedule II. Interim final rule, with request for comments.

PubMed

2017-03-23

On July 1, 2016, the U.S. Food and Drug Administration (FDA) approved a new drug application for Syndros, a drug product consisting of dronabinol [(-)-delta-9-trans-tetrahydrocannabinol (delta-9-THC)] oral solution. Thereafter, the Department of Health and Human Services (HHS) provided the Drug Enforcement Administration (DEA) with a scheduling recommendation that would result in Syndros (and other oral solutions containing dronabinol) being placed in schedule II of the Controlled Substances Act (CSA). In accordance with the CSA, as revised by the Improving Regulatory Transparency for New Medical Therapies Act, DEA is hereby issuing an interim final rule placing FDA-approved products of oral solutions containing dronabinol in schedule II of the CSA.

Inhibitory control gains from higher-order cognitive strategy training.

PubMed

Motes, Michael A; Gamino, Jacquelyn F; Chapman, Sandra B; Rao, Neena K; Maguire, Mandy J; Brier, Matthew R; Kraut, Michael A; Hart, John

2014-02-01

The present study examined the transfer of higher-order cognitive strategy training to inhibitory control. Middle school students enrolled in a comprehension- and reasoning-focused cognitive strategy training program and passive controls participated. The training program taught students a set of steps for inferring essential gist or themes from materials. Both before and after training or a comparable duration in the case of the passive controls, participants completed a semantically cued Go/No-Go task that was designed to assess the effects of depth of semantic processing on response inhibition and components of event-related potentials (ERP) related to response inhibition. Depth of semantic processing was manipulated by varying the level of semantic categorization required for response selection and inhibition. The SMART-trained group showed inhibitory control gains and changes in fronto-central P3 ERP amplitudes on inhibition trials; whereas, the control group did not. The results provide evidence of the transfer of higher-order cognitive strategy training to inhibitory control and modulation of ERPs associated with semantically cued inhibitory control. The findings are discussed in terms of implications for cognitive strategy training, models of cognitive abilities, and education. Published by Elsevier Inc.

Shift work, age, and performance : investigation of the 2-2-1 shift schedule used in air traffic control facilities. I., The sleep/wake cycle.

DOT National Transportation Integrated Search

1995-05-01

Air Traffic Control Specialists (ATCS) work rotating shift schedules for most of their careers. Specifically, many work a counterclockwise rotating shift schedule, called the 2-2-1, or some variation of the schedule. The 2-2-1 involves rotating from ...

Multivariable Control Law Design for the AFTI/F-16 with a Failed Control Surface Using a Parameter-Adaptive Controller.

DTIC Science & Technology

1987-12-01

Appendix D: Macro Listings D-1 Appendix E: MATRIXx Simulation E-1 Bibiliography Vita iv e List of Figures Figure Page 1-1 Self -Tuning Regulator 6 2-1 AFTI...Command 59 4-25 Yaw Rate Command - Three Pulses 60 4-26 Adaptive Yaw Rate Respose - Three Pulses 61 4-27 Adaptive Pitch Angle Response - Three Pulses 62 4...several types of adaptive controllers (regulators). Three of the simplest controllers are gain scheduling, model reference, and self -tuning

76 FR 77895 - Schedules of Controlled Substances: Placement of Ezogabine Into Schedule V

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-15

... ester, is a new chemical substance with central nervous system depressant properties and is classified... nervous system as an anticonvulsant and the potential side effects of the drug therein, warrant closer... the central nervous system is alone not enough to merit its inclusion into Schedule IV of the CSA, nor...

In-Space Crew-Collaborative Task Scheduling

NASA Technical Reports Server (NTRS)

Jaap, John; Meyer, Patrick; Davis, Elizabeth; Richardson, Lea

2007-01-01

For all past and current human space missions, the final scheduling of tasks to be done in space has been devoid of crew control, flexibility, and insight. Ground controllers, with minimal input from the crew, schedule the tasks and uplink the timeline to the crew or uplink the command sequences to the hardware. Prior to the International Space Station (ISS), the crew could make requests about tomorrow s timeline, they could omit a task, or they could request that something in the timeline be delayed. This lack of control over one's own schedule has had negative consequences. There is anecdotal consensus among astronauts that control over their own schedules will mitigate the stresses of long duration missions. On ISS, a modicum of crew control is provided by the job jar. Ground controllers prepare a task list (a.k.a. "job jar") of non-conflicting tasks from which jobs can be chosen by the in space crew. Because there is little free time and few interesting non-conflicting activities, the task-list approach provides little relief from the tedium of being micro-managed by the timeline. Scheduling for space missions is a complex and laborious undertaking which usually requires a large cadre of trained specialists and suites of complex software tools. It is a giant leap from today s ground prepared timeline (with a job jar) to full crew control of the timeline. However, technological advances, currently in-work or proposed, make it reasonable to consider scheduling a collaborative effort by the ground-based teams and the in-space crew. Collaboration would allow the crew to make minor adjustments, add tasks according to their preferences, understand the reasons for the placement of tasks on the timeline, and provide them a sense of control. In foreseeable but extraordinary situations, such as a quick response to anomalies and extended or unexpected loss of signal, the crew should have the autonomous ability to make appropriate modifications to the timeline, extend the

LPV Modeling and Control for Active Flutter Suppression of a Smart Airfoil

NASA Technical Reports Server (NTRS)

Al-Hajjar, Ali M. H.; Al-Jiboory, Ali Khudhair; Swei, Sean Shan-Min; Zhu, Guoming

2018-01-01

In this paper, a novel technique of linear parameter varying (LPV) modeling and control of a smart airfoil for active flutter suppression is proposed, where the smart airfoil has a groove along its chord and contains a moving mass that is used to control the airfoil pitching and plunging motions. The new LPV modeling technique is proposed that uses mass position as a scheduling parameter to describe the physical constraint of the moving mass, in addition the hard constraint at the boundaries is realized by proper selection of the parameter varying function. Therefore, the position of the moving mass and the free stream airspeed are considered the scheduling parameters in the study. A state-feedback based LPV gain-scheduling controller with guaranteed H infinity performance is presented by utilizing the dynamics of the moving mass as scheduling parameter at a given airspeed. The numerical simulations demonstrate the effectiveness of the proposed LPV control architecture by significantly improving the performance while reducing the control effort.

The Official Control beyond the Official Control. How To Plan And Schedule Controls Starting From Risk Assessment Along The Agro-Food Supply Chain.

PubMed

Panunzio, M F; Caporizzi, R; Lagravinese, D; Conversano, M

2015-01-01

Every year the Italian Ministry of Health, on the basis of regional data, draws up the "Report on Official Controls" to be submitted to the Parliament. The report contains abundant data, diagrams and charts and illustrates the number and type of official controls (OC) performed by the pertinent Bodies (Ministry of Health, Regional and Local Health Authorities) over the previous year on Food Business Operators (FBO), in accordance with the EC Regulation 882/2004. The trend - which has consolidated over the years - relates to the multiplicity of OC and shows a decrease of such controls compared to an increase in "non-conformities". OC frequency is established by the Regional Authorities on the basis of the categorisation of both a "generic risk" for companies calculated taking into account the probability of occurrence of a "non-conformity", and a "specific" risk, assessed on the basis of the results of the OC actually performed on a given "Operatore del Settore Alimentare" (Food Sector Operator, in Italian: OSA). Thus, categorisation (i.e. the probability of occurrence of non-conformities) is the main driver of the OC scheduling and planning process. We have been asking ourselves whether the current OC planning/scheduling method is still suitable for ensuring food safety in the face of internalisation of the food supply chain. As a matter of fact, food safety is now becoming increasingly variable due to the globalization of consumption where "farm to fork", rather than "border to fork", food safety must be ensured. On the basis of these considerations, a different OC planning /scheduling method is being proposed based on the assessment of risks and the estimation of the occurrence of the same along the agro-food chain.

Development of Ti microalloyed high strength steel plate by controlling thermo-mechanical control process schedule

NASA Astrophysics Data System (ADS)

Xia, Jinian; Huo, Xiangdong; Li, Liejun; Peng, Zhengwu; Chen, Songjun

2017-12-01

In this study, the TMCP parameters including non-recrystallization temperature (Tnr) and optimal isothermal temperature were determined by thermal simulation experiments, and a new Ti microalloyed high strength steel plate was developed by controlling thermo-mechanical control process (TMCP) schedule. The effects of TMCP process on microstructural features, precipitation behavior and mechanical properties of Ti microalloyed high strength steel plate were investigated. The results revealed that the double-stage rolling process consist of rolling in the γ recrystallization region and the γ non-recrystallization region was benefical to promoting the mechanical properties of Ti microalloyed steel by achieving grain refinement. It was also found that large amounts of fine TiC (<10 nm) particles were precipitated during the isothermal treatment at 600 °C, which generated a 215 MPa precipitation strengthening effect.

Binocular contrast-gain control for natural scenes: Image structure and phase alignment.

PubMed

Huang, Pi-Chun; Dai, Yu-Ming

2018-05-01

In the context of natural scenes, we applied the pattern-masking paradigm to investigate how image structure and phase alignment affect contrast-gain control in binocular vision. We measured the discrimination thresholds of bandpass-filtered natural-scene images (targets) under various types of pedestals. Our first experiment had four pedestal types: bandpass-filtered pedestals, unfiltered pedestals, notch-filtered pedestals (which enabled removal of the spatial frequency), and misaligned pedestals (which involved rotation of unfiltered pedestals). Our second experiment featured six types of pedestals: bandpass-filtered, unfiltered, and notch-filtered pedestals, and the corresponding phase-scrambled pedestals. The thresholds were compared for monocular, binocular, and dichoptic viewing configurations. The bandpass-filtered pedestal and unfiltered pedestals showed classic dipper shapes; the dipper shapes of the notch-filtered, misaligned, and phase-scrambled pedestals were weak. We adopted a two-stage binocular contrast-gain control model to describe our results. We deduced that the phase-alignment information influenced the contrast-gain control mechanism before the binocular summation stage and that the phase-alignment information and structural misalignment information caused relatively strong divisive inhibition in the monocular and interocular suppression stages. When the pedestals were phase-scrambled, the elimination of the interocular suppression processing was the most convincing explanation of the results. Thus, our results indicated that both phase-alignment information and similar image structures cause strong interocular suppression. Copyright © 2018 Elsevier Ltd. All rights reserved.

40 CFR 716.60 - Reporting schedule.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Reporting schedule. 716.60 Section 716.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.60 Reporting schedule. (a) General requirements...

40 CFR 716.60 - Reporting schedule.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Reporting schedule. 716.60 Section 716.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.60 Reporting schedule. (a) General requirements...

40 CFR 716.60 - Reporting schedule.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Reporting schedule. 716.60 Section 716.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.60 Reporting schedule. (a) General requirements...

40 CFR 716.60 - Reporting schedule.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Reporting schedule. 716.60 Section 716.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.60 Reporting schedule. (a) General requirements...

40 CFR 716.60 - Reporting schedule.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Reporting schedule. 716.60 Section 716.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.60 Reporting schedule. (a) General requirements...

40 CFR 52.1175 - Compliance schedules.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Compliance schedules. 52.1175 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Michigan § 52.1175 Compliance schedules. (a... Rule 336.49 of the Michigan Air Pollution Control Commission provides for individual compliance...

Gain dynamics of clad-pumped Yb-fiber amplifier and intensity noise control.

PubMed

Zhao, Jian; Guiraud, Germain; Floissat, Florian; Gouhier, Benoit; Rota-Rodrigo, Sergio; Traynor, Nicholas; Santarelli, Giorgio

2017-01-09

Gain dynamics study provides an attractive method to understand the intensity noise behavior in fiber amplifiers. Here, the gain dynamics of a medium power (5 W) clad-pumped Yb-fiber amplifier is experimentally evaluated by measuring the frequency domain transfer functions for the input seed and pump lasers from 10 Hz to 1 MHz. We study gain dynamic behavior of the fiber amplifier in the presence of significant residual pump power (compared to the seed power), showing that the seed transfer function is strongly saturated at low Fourier frequencies while the pump power modulation transfer function is nearly unaffected. The characterization of relative intensity noise (RIN) of the fiber amplifier is well explained by the gain dynamics analysis. Finally, a 600 kHz bandwidth feedback loop using an acoustic-optical modulator (AOM) controlling the seed intensity is successfully demonstrated to suppress the broadband laser intensity noise. A maximum noise reduction of about 30 dB is achieved leading to a RIN of -152 dBc/Hz (~1 kHz-10 MHz) at 2.5 W output power.

Estimation of Airline Benefits from Avionics Upgrade under Preferential Merge Re-sequence Scheduling

NASA Technical Reports Server (NTRS)

Kotegawa, Tatsuya; Cayabyab, Charlene Anne; Almog, Noam

2013-01-01

Modernization of the airline fleet avionics is essential to fully enable future technologies and procedures for increasing national airspace system capacity. However in the current national airspace system, system-wide benefits gained by avionics upgrade are not fully directed to aircraft/airlines that upgrade, resulting in slow fleet modernization rate. Preferential merge re-sequence scheduling is a best-equipped-best-served concept designed to incentivize avionics upgrade among airlines by allowing aircraft with new avionics (high-equipped) to be re-sequenced ahead of aircraft without the upgrades (low-equipped) at enroute merge waypoints. The goal of this study is to investigate the potential benefits gained or lost by airlines under a high or low-equipped fleet scenario if preferential merge resequence scheduling is implemented.

77 FR 75075 - Schedules of Controlled Substances: Placement of Lorcaserin Into Schedule IV

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-19

... marketing lorcaserin as a Schedule IV substance will decrease its abuse, as opposed to marketing it as an... for marketing by FDA as an addition to a reduced-calorie diet and exercise, for chronic weight... to Section 3(d)(1) of Executive Order 12866 and the principles reaffirmed in Executive Order 13563...

21 CFR 1305.04 - Persons entitled to order Schedule I and II controlled substances.

Code of Federal Regulations, 2011 CFR

2011-04-01

... to order Schedule I and II controlled substances. (a) Only persons who are registered with DEA under... are registered with DEA under section 1008 of the Act (21 U.S.C. 958) to export these substances may obtain and use DEA Form 222 (order forms) or issue electronic orders for these substances. Persons not...

21 CFR 1305.04 - Persons entitled to order Schedule I and II controlled substances.

Code of Federal Regulations, 2010 CFR

2010-04-01

... to order Schedule I and II controlled substances. (a) Only persons who are registered with DEA under... are registered with DEA under section 1008 of the Act (21 U.S.C. 958) to export these substances may obtain and use DEA Form 222 (order forms) or issue electronic orders for these substances. Persons not...

Cognitive Control of Eating: the Role of Memory in Appetite and Weight Gain.

PubMed

Higgs, Suzanne; Spetter, Maartje S

2018-03-01

The present review organises the recent literature on the role of memory in eating behaviours and provides an overview of the current evidence relating to the associations between memory and weight gain. Research over the last few years has highlighted working memory as an important cognitive process that underpins many aspects of appetite control. Recent work on episodic memory and appetite has replicated work showing that manipulating memory for recent eating affects later consumption and extended this work to examine associations between individual differences in memory and eating behaviours. Poorer episodic memory ability is related to a reduced sensitivity to internal states of hunger and satiety and a tendency towards uncontrolled eating. There is also recent evidence to suggest that working memory and episodic memory impairments are related to weight gain and high BMI. Working memory and episodic memory are core cognitive processes that are critical for food-related decision-making, and disruption to these processes contributes to problems with appetite control and weight gain, which suggests that weight loss programmes might be improved by the addition of cognitive training.

Application of automatic gain control for radiometer diagnostic in SST-1 tokamak.

PubMed

Makwana, Foram R; Siju, Varsha; Edappala, Praveenlal; Pathak, S K

2017-12-01

This paper describes the characterisation of a negative feedback type of automatic gain control (AGC) circuit that will be an integral part of the heterodyne radiometer system operating at a frequency range of 75-86 GHz at SST-1 tokamak. The developed AGC circuit is a combination of variable gain amplifier and log amplifier which provides both gain and attenuation typically up to 15 dB and 45 dB, respectively, at a fixed set point voltage and it has been explored for the first time in tokamak radiometry application. The other important characteristics are that it exhibits a very fast response time of 390 ns to understand the fast dynamics of electron cyclotron emission and can operate at very wide input RF power dynamic range of around 60 dB that ensures signal level within the dynamic range of the detection system.

Reduced state feedback gain computation. [optimization and control theory for aircraft control

NASA Technical Reports Server (NTRS)

Kaufman, H.

1976-01-01

Because application of conventional optimal linear regulator theory to flight controller design requires the capability of measuring and/or estimating the entire state vector, it is of interest to consider procedures for computing controls which are restricted to be linear feedback functions of a lower dimensional output vector and which take into account the presence of measurement noise and process uncertainty. Therefore, a stochastic linear model that was developed is presented which accounts for aircraft parameter and initial uncertainty, measurement noise, turbulence, pilot command and a restricted number of measurable outputs. Optimization with respect to the corresponding output feedback gains was performed for both finite and infinite time performance indices without gradient computation by using Zangwill's modification of a procedure originally proposed by Powell. Results using a seventh order process show the proposed procedures to be very effective.

Identification and Control of Non-Linear Time-Varying Dynamical Systems Using Artificial Neural Networks

DTIC Science & Technology

1992-09-01

finding an inverse plant such as was done by Bertrand [BD91] and by Levin, Gewirtzman and Inbar in a binary type inverse controller [LGI91], to self tuning...gain robust control. 2) Self oscillating adaptive controller. 3) Gain scheduling. 4) Self tuning. 5) Model-reference adaptive systems. Although the...of multidimensional systems (CS881 as well as aircraft [HG90]. The self oscillating method is also a feedback based mechanism, utilizing a relay in the

X-33 Ascent Flight Controller Design by Trajectory Linearization: A Singular Perturbational Approach

NASA Technical Reports Server (NTRS)

Zhu, J. Jim; Banker, Brad D.; Hall, Charles E.

2000-01-01

The flight control of X-33 poses a challenge to conventional gain-scheduled flight controllers due to its large attitude maneuvers from liftoff to orbit and reentry. In addition, a wide range of uncertainties in vehicle handling qualities and disturbances must be accommodated by the attitude control system. Nonlinear tracking and decoupling control by trajectory linearization can be viewed as the ideal gain-scheduling controller designed at every point on the flight trajectory. Therefore it provides robust stability and performance at all stages of flight without interpolation of controller gains and eliminates costly controller redesigns due to minor airframe alteration or mission reconfiguration. In this paper, a prototype trajectory linearization design for an X-33 ascent flight controller is presented along with 3-DOF and 6-DOF simulation results. It is noted that the 6-DOF results were obtained from the 3-DOF design with only a few hours of tuning, which demonstrates the inherent robustness of the design technique. It is this "plug-and-play" feature that is much needed by NASA for the development, test and routine operations of the RLV'S. Plans for further research are also presented, and refined 6-DOF simulation results will be presented in the final version of the paper.

Evaluation of different infant vaccination schedules incorporating pneumococcal vaccination (The Vietnam Pneumococcal Project): protocol of a randomised controlled trial

PubMed Central

Temple, Beth; Toan, Nguyen Trong; Uyen, Doan Y; Balloch, Anne; Bright, Kathryn; Cheung, Yin Bun; Licciardi, Paul; Nguyen, Cattram Duong; Phuong, Nguyen Thi Minh; Satzke, Catherine; Smith-Vaughan, Heidi; Vu, Thi Que Huong; Huu, Tran Ngoc; Mulholland, Edward Kim

2018-01-01

Introduction WHO recommends the use of pneumococcal conjugate vaccine (PCV) as a priority. However, there are many countries yet to introduce PCV, especially in Asia. This trial aims to evaluate different PCV schedules and to provide a head-to-head comparison of PCV10 and PCV13 in order to generate evidence to assist with decisions regarding PCV introduction. Schedules will be compared in relation to their immunogenicity and impact on nasopharyngeal carriage of Streptococcus pneumoniae and Haemophilus influenzae. Methods and analysis This randomised, single-blind controlled trial involves 1200 infants recruited at 2 months of age to one of six infant PCV schedules: PCV10 in a 3+1, 3+0, 2+1 or two-dose schedule; PCV13 in a 2+1 schedule; and controls that receive two doses of PCV10 and 18 and 24 months. An additional control group of 200 children is recruited at 18 months that receive one dose of PCV10 at 24 months. All participants are followed up until 24 months of age. The primary outcome is the post-primary series immunogenicity, expressed as the proportions of participants with serotype-specific antibody levels ≥0.35 µg/mL for each serotype in PCV10. Ethics and dissemination Ethical approval has been obtained from the Human Research Ethics Committee of the Northern Territory Department of Health and Menzies School of Health Research (EC00153) and the Vietnam Ministry of Health Ethics Committee. The results, interpretation and conclusions will be presented to parents and guardians, at national and international conferences, and published in peer-reviewed open access journals. Trial registration number NCT01953510; Pre-results. PMID:29884695

Double- and Triple-Duty Caregiving Men: An Examination of Subjective Stress and Perceived Schedule Control.

PubMed

DePasquale, Nicole; Zarit, Steven H; Mogle, Jacqueline; Moen, Phyllis; Hammer, Leslie B; Almeida, David M

2018-04-01

Based on the stress process model of family caregiving, this study examined subjective stress appraisals and perceived schedule control among men employed in the long-term care industry (workplace-only caregivers) who concurrently occupied unpaid family caregiving roles for children (double-duty child caregivers), older adults (double-duty elder caregivers), and both children and older adults (triple-duty caregivers). Survey responses from 123 men working in nursing home facilities in the United States were analyzed using multiple linear regression models. Results indicated that workplace-only and double- and triple-duty caregivers' appraised primary stress similarly. However, several differences emerged with respect to secondary role strains, specifically work-family conflict, emotional exhaustion, and turnover intentions. Schedule control also constituted a stress buffer for double- and triple-duty caregivers, particularly among double-duty elder caregivers. These findings contribute to the scarce literature on double- and triple-duty caregiving men and have practical implications for recruitment and retention strategies in the health care industry.

Light-controlled resistors provide quadrature signal rejection for high-gain servo systems

NASA Technical Reports Server (NTRS)

Mc Cauley, D. D.

1967-01-01

Servo amplifier feedback system, in which the phase sensitive detection, low pass filtering, and multiplication functions required for quadrature rejection, are preformed by light-controlled photoresistors, eliminates complex circuitry. System increases gain, improves signal-to-noise ratio, and eliminates the necessity for compensation.

Feeding and metabolic consequences of scheduled consumption of large, binge-type meals of high fat diet in the Sprague-Dawley rat.

PubMed

Bake, T; Morgan, D G A; Mercer, J G

2014-04-10

Providing rats and mice with access to palatable high fat diets for a short period each day induces the consumption of substantial binge-like meals. Temporal food intake structure (assessed using the TSE PhenoMaster/LabMaster system) and metabolic outcomes (oral glucose tolerance tests [oGTTs], and dark phase glucose and insulin profiles) were examined in Sprague-Dawley rats given access to 60% high fat diet on one of 3 different feeding regimes: ad libitum access (HF), daily 2 h-scheduled access from 6 to 8 h into the dark phase (2 h-HF), and twice daily 1 h-scheduled access from both 1-2 h and 10-11 h into the dark phase (2×1 h-HF). Control diet remained available during the scheduled access period. HF rats had the highest caloric intake, body weight gain, body fat mass and plasma insulin. Both schedule-fed groups rapidly adapted their feeding behaviour to scheduled access, showing large meal/bingeing behaviour with 44% or 53% of daily calories consumed from high fat diet during the 2 h or 2×1 h scheduled feed(s), respectively. Both schedule-fed groups had an intermediate caloric intake and body fat mass compared to HF and control (CON) groups. Temporal analysis of food intake indicated that schedule-fed rats consumed large binge-type high fat meals without a habitual decrease in preceding intake on control diet, suggesting that a relative hypocaloric state was not responsible or required for driving the binge episode, and substantiating previous indications that binge eating may not be driven by hypothalamic energy balance neuropeptides. In an oGTT, both schedule-fed groups had impaired glucose tolerance with higher glucose and insulin area under the curve, similar to the response in ad libitum HF fed rats, suggesting that palatable feeding schedules represent a potential metabolic threat. Scheduled feeding on high fat diet produces similar metabolic phenotypes to mandatory (no choice) high fat feeding and may be a more realistic platform for mechanistic study

Teaching Stimulus Control via Class-Wide Multiple Schedules of Reinforcement in Public Elementary School Classrooms

ERIC Educational Resources Information Center

Torelli, Jessica N.; Lloyd, Blair P.; Diekman, Claire A.; Wehby, Joseph H.

2017-01-01

In elementary school classrooms, students commonly recruit teacher attention at inappropriately high rates or at inappropriate times. Multiple schedule interventions have been used to teach stimulus control by signaling to students when reinforcement is and is not available contingent on an appropriate response. The purpose of the current study…

Automatic gain control of neural coupling during cooperative hand movements.

PubMed

Thomas, F A; Dietz, V; Schrafl-Altermatt, M

2018-04-13

Cooperative hand movements (e.g. opening a bottle) are controlled by a task-specific neural coupling, reflected in EMG reflex responses contralateral to the stimulation site. In this study the contralateral reflex responses in forearm extensor muscles to ipsilateral ulnar nerve stimulation was analyzed at various resistance and velocities of cooperative hand movements. The size of contralateral reflex responses was closely related to the level of forearm muscle activation required to accomplish the various cooperative hand movement tasks. This indicates an automatic gain control of neural coupling that allows a rapid matching of corrective forces exerted at both sides of an object with the goal 'two hands one action'.

Effects on employees of controlling working hours and working schedules.

PubMed

Kubo, T; Takahashi, M; Togo, F; Liu, X; Shimazu, A; Tanaka, K; Takaya, M

2013-03-01

High levels of control over working time and low variability in working hours have been associated with improved health-related outcomes. The potential mechanisms for this association remain unclear. To examine how work-time control and variability of working times are associated with fatigue recovery, sleep quality, work-life balance, and 'near misses' at work. Manufacturing sector employees completed a questionnaire that assessed work-time control, work-time variability, fatigue recovery, sleep quality, work-life balance and the frequency of near misses in the past 6 months. Mixed model analysis of covariance and multiple logistic regression analysis tested the main effects of work-time control and variability and their interaction, while adjusting for age, sex, work schedules, and overtime work in the past month. Subscales of work-time control were also investigated (control over daily working hours and over days off). One thousand three hundred and seventy-two completed questionnaires were returned, a response rate of 69%. A significantly higher quality of sleep and better work-life balance were found in the 'high control with low variability' reference group than in the other groups. Significantly better recovery of fatigue was also observed in the group having control over days off with low variability. While near misses were more frequent in the group with high control over daily working hours coupled with high variability compared with the reference group this was not significant. High work-time control and low variability were associated with favourable outcomes of health and work-life balance. This combined effect was not observed for the safety outcome addressed here.

Determinants of weight gain in the action to control cardiovascular risk in diabetes trial.

PubMed

Fonseca, Vivian; McDuffie, Roberta; Calles, Jorge; Cohen, Robert M; Feeney, Patricia; Feinglos, Mark; Gerstein, Hertzel C; Ismail-Beigi, Faramarz; Morgan, Timothy M; Pop-Busui, Rodica; Riddle, Matthew C

2013-08-01

Identify determinants of weight gain in people with type 2 diabetes mellitus (T2DM) allocated to intensive versus standard glycemic control in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. We studied determinants of weight gain over 2 years in 8,929 participants (4,425 intensive arm and 4,504 standard arm) with T2DM in the ACCORD trial. We used general linear models to examine the association between each baseline characteristic and weight change at the 2-year visit. We fit a linear regression of change in weight and A1C and used general linear models to examine the association between each medication at baseline and weight change at the 2-year visit, stratified by glycemia allocation. There was significantly more weight gain in the intensive glycemia arm of the trial compared with the standard arm (3.0 ± 7.0 vs. 0.3 ± 6.3 kg). On multivariate analysis, younger age, male sex, Asian race, no smoking history, high A1C, baseline BMI of 25-35, high waist circumference, baseline insulin use, and baseline metformin use were independently associated with weight gain over 2 years. Reduction of A1C from baseline was consistently associated with weight gain only when baseline A1C was elevated. Medication usage accounted for <15% of the variability of weight change, with initiation of thiazolidinedione (TZD) use the most prominent factor. Intensive participants who never took insulin or a TZD had an average weight loss of 2.9 kg during the first 2 years of the trial. In contrast, intensive participants who had never previously used insulin or TZD but began this combination after enrolling in the ACCORD trial had a weight gain of 4.6-5.3 kg at 2 years. Weight gain in ACCORD was greater with intensive than with standard treatment and generally associated with reduction of A1C from elevated baseline values. Initiation of TZD and/or insulin therapy was the most important medication-related factor associated with weight gain.

Sensory gain control (amplification) as a mechanism of selective attention: electrophysiological and neuroimaging evidence.

PubMed Central

Hillyard, S A; Vogel, E K; Luck, S J

1998-01-01

Both physiological and behavioral studies have suggested that stimulus-driven neural activity in the sensory pathways can be modulated in amplitude during selective attention. Recordings of event-related brain potentials indicate that such sensory gain control or amplification processes play an important role in visual-spatial attention. Combined event-related brain potential and neuroimaging experiments provide strong evidence that attentional gain control operates at an early stage of visual processing in extrastriate cortical areas. These data support early selection theories of attention and provide a basis for distinguishing between separate mechanisms of attentional suppression (of unattended inputs) and attentional facilitation (of attended inputs). PMID:9770220

Active flutter suppression using optical output feedback digital controllers

NASA Technical Reports Server (NTRS)

1982-01-01

A method for synthesizing digital active flutter suppression controllers using the concept of optimal output feedback is presented. A convergent algorithm is employed to determine constrained control law parameters that minimize an infinite time discrete quadratic performance index. Low order compensator dynamics are included in the control law and the compensator parameters are computed along with the output feedback gain as part of the optimization process. An input noise adjustment procedure is used to improve the stability margins of the digital active flutter controller. Sample rate variation, prefilter pole variation, control structure variation and gain scheduling are discussed. A digital control law which accommodates computation delay can stabilize the wing with reasonable rms performance and adequate stability margins.

Irrigation scheduling and controlling crop water use efficiency with Infrared Thermometry

USDA-ARS?s Scientific Manuscript database

Scientific methods for irrigation scheduling include weather, soil and plant-based techniques. Infrared thermometers can be used a non-invasive practice to monitor canopy temperature and better manage irrigation scheduling. This presentation will discuss the theoretical basis for monitoring crop can...

Production scheduling and rescheduling with genetic algorithms.

PubMed

Bierwirth, C; Mattfeld, D C

1999-01-01

A general model for job shop scheduling is described which applies to static, dynamic and non-deterministic production environments. Next, a Genetic Algorithm is presented which solves the job shop scheduling problem. This algorithm is tested in a dynamic environment under different workload situations. Thereby, a highly efficient decoding procedure is proposed which strongly improves the quality of schedules. Finally, this technique is tested for scheduling and rescheduling in a non-deterministic environment. It is shown by experiment that conventional methods of production control are clearly outperformed at reasonable run-time costs.

Two-Level Scheduling for Video Transmission over Downlink OFDMA Networks

PubMed Central

Tham, Mau-Luen

2016-01-01

This paper presents a two-level scheduling scheme for video transmission over downlink orthogonal frequency-division multiple access (OFDMA) networks. It aims to maximize the aggregate quality of the video users subject to the playback delay and resource constraints, by exploiting the multiuser diversity and the video characteristics. The upper level schedules the transmission of video packets among multiple users based on an overall target bit-error-rate (BER), the importance level of packet and resource consumption efficiency factor. Instead, the lower level renders unequal error protection (UEP) in terms of target BER among the scheduled packets by solving a weighted sum distortion minimization problem, where each user weight reflects the total importance level of the packets that has been scheduled for that user. Frequency-selective power is then water-filled over all the assigned subcarriers in order to leverage the potential channel coding gain. Realistic simulation results demonstrate that the proposed scheme significantly outperforms the state-of-the-art scheduling scheme by up to 6.8 dB in terms of peak-signal-to-noise-ratio (PSNR). Further test evaluates the suitability of equal power allocation which is the common assumption in the literature. PMID:26906398

A Technology-Mediated Behavioral Weight Gain Prevention Intervention for College Students: Controlled, Quasi-Experimental Study

PubMed Central

Monroe, Courtney M; Turner-McGrievy, Gabrielle; Sundstrom, Beth; Larsen, Chelsea; Magradey, Karen; Wilcox, Sara; Brandt, Heather M

2016-01-01

Background Both men and women are vulnerable to weight gain during the college years, and this phenomenon is linked to an increased risk of several chronic diseases and mortality. Technology represents an attractive medium for the delivery of weight control interventions focused on college students, given its reach and appeal among this population. However, few technology-mediated weight gain prevention interventions have been evaluated for college students. Objective This study examined a new technology-based, social media-facilitated weight gain prevention intervention for college students. Methods Undergraduates (n =58) in two sections of a public university course were allocated to either a behavioral weight gain prevention intervention (Healthy Weight, HW; N=29) or a human papillomavirus (HPV) vaccination awareness intervention (control; N=29). All students were enrolled, regardless of initial body weight or expressed interest in weight management. The interventions delivered 8 lessons via electronic newsletters and Facebook postings over 9 weeks, which were designed to foster social support and introduce relevant educational content. The HW intervention targeted behavioral strategies to prevent weight gain and provided participants with a Wi-Fi-enabled scale and an electronic physical activity tracker to facilitate weight regulation. A repeated-measures analysis of variance was conducted to examine within- and between-group differences in measures of self-reported weight control practices and objectively measured weight. Use of each intervention medium and device was objectively tracked, and intervention satisfaction measures were obtained. Results Students remained weight stable (HW: −0.48+1.9 kg; control: −0.45+1.4 kg), with no significant difference between groups over 9 weeks (P =.94). However, HW students reported a significantly greater increase in the number of appropriate weight control strategies than did controls (2.1+4.5 vs −1

A Technology-Mediated Behavioral Weight Gain Prevention Intervention for College Students: Controlled, Quasi-Experimental Study.

PubMed

West, Delia Smith; Monroe, Courtney M; Turner-McGrievy, Gabrielle; Sundstrom, Beth; Larsen, Chelsea; Magradey, Karen; Wilcox, Sara; Brandt, Heather M

2016-06-13

Both men and women are vulnerable to weight gain during the college years, and this phenomenon is linked to an increased risk of several chronic diseases and mortality. Technology represents an attractive medium for the delivery of weight control interventions focused on college students, given its reach and appeal among this population. However, few technology-mediated weight gain prevention interventions have been evaluated for college students. This study examined a new technology-based, social media-facilitated weight gain prevention intervention for college students. Undergraduates (n =58) in two sections of a public university course were allocated to either a behavioral weight gain prevention intervention (Healthy Weight, HW; N=29) or a human papillomavirus (HPV) vaccination awareness intervention (control; N=29). All students were enrolled, regardless of initial body weight or expressed interest in weight management. The interventions delivered 8 lessons via electronic newsletters and Facebook postings over 9 weeks, which were designed to foster social support and introduce relevant educational content. The HW intervention targeted behavioral strategies to prevent weight gain and provided participants with a Wi-Fi-enabled scale and an electronic physical activity tracker to facilitate weight regulation. A repeated-measures analysis of variance was conducted to examine within- and between-group differences in measures of self-reported weight control practices and objectively measured weight. Use of each intervention medium and device was objectively tracked, and intervention satisfaction measures were obtained. Students remained weight stable (HW: -0.48+1.9 kg; control: -0.45+1.4 kg), with no significant difference between groups over 9 weeks (P =.94). However, HW students reported a significantly greater increase in the number of appropriate weight control strategies than did controls (2.1+4.5 vs -1.1+3.4, respectively; P =.003) and there was no increase in

Responsive versus scheduled feeding for preterm infants.

PubMed

Watson, Julie; McGuire, William

2015-10-13

Feeding preterm infants in response to their hunger and satiation cues (responsive, cue-based, or infant-led feeding) rather than at scheduled intervals might enhance infants' and parents' experience and satisfaction, help in the establishment of independent oral feeding, increase nutrient intake and growth rates, and allow earlier hospital discharge. To assess the effect of feeding preterm infants on a responsive basis versus feeding prescribed volumes at scheduled intervals on growth, duration of hospital stay, and parental satisfaction. We used the standard search strategy of the Cochrane Neonatal Review Group. This included searches of the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 9, 2015), MEDLINE (1966 to September 2015), EMBASE (1980 to September 2015), and CINAHL (1982 to September 2015), conference proceedings, previous reviews, and trial registries. Randomised controlled trials (RCTs) or quasi-RCTs that compared a policy of feeding preterm infants on a responsive basis versus feeding at scheduled intervals. Two review authors assessed trial eligibility and risk of bias and undertook data extraction independently. We analysed the treatment effects in the individual trials and reported the risk ratio and risk difference for dichotomous data and mean difference (MD) for continuous data, with respective 95% confidence intervals (CIs). We used a fixed-effect model in meta-analyses and explored the potential causes of heterogeneity in sensitivity analyses. We found nine eligible RCTs including 593 infants in total. These trials compared responsive with scheduled interval regimens in preterm infants in the transition phase from intragastric tube to oral feeding. The trials were generally small and contained various methodological weaknesses including lack of blinding and incomplete assessment of all randomised participants. Meta-analyses, although limited by data quality and availability, suggest that responsive feeding

Control over the Scheduling of Simulated Office Work Reduces the Impact of Workload on Mental Fatigue and Task Performance

ERIC Educational Resources Information Center

Hockey, G. Robert J.; Earle, Fiona

2006-01-01

Two experiments tested the hypothesis that task-induced mental fatigue is moderated by control over work scheduling. Participants worked for 2 hr on simulated office work, with control manipulated by a yoking procedure. Matched participants were assigned to conditions of either high control (HC) or low control (LC). HC participants decided their…

An interpolated activity during the knowledge-of-results delay interval eliminates the learning advantages of self-controlled feedback schedules.

PubMed

Carter, Michael J; Ste-Marie, Diane M

2017-03-01

The learning advantages of self-controlled knowledge-of-results (KR) schedules compared to yoked schedules have been linked to the optimization of the informational value of the KR received for the enhancement of one's error-detection capabilities. This suggests that information-processing activities that occur after motor execution, but prior to receiving KR (i.e., the KR-delay interval) may underlie self-controlled KR learning advantages. The present experiment investigated whether self-controlled KR learning benefits would be eliminated if an interpolated activity was performed during the KR-delay interval. Participants practiced a waveform matching task that required two rapid elbow extension-flexion reversals in one of four groups using a factorial combination of choice (self-controlled, yoked) and KR-delay interval (empty, interpolated). The waveform had specific spatial and temporal constraints, and an overall movement time goal. The results indicated that the self-controlled + empty group had superior retention and transfer scores compared to all other groups. Moreover, the self-controlled + interpolated and yoked + interpolated groups did not differ significantly in retention and transfer; thus, the interpolated activity eliminated the typically found learning benefits of self-controlled KR. No significant differences were found between the two yoked groups. We suggest the interpolated activity interfered with information-processing activities specific to self-controlled KR conditions that occur during the KR-delay interval and that these activities are vital for reaping the associated learning benefits. These findings add to the growing evidence that challenge the motivational account of self-controlled KR learning advantages and instead highlights informational factors associated with the KR-delay interval as an important variable for motor learning under self-controlled KR schedules.

Planning and scheduling for success

NASA Technical Reports Server (NTRS)

Manzanera, Ignacio

1994-01-01

Planning and scheduling programs are excellent management tools when properly introduced to the project management team and regularly maintained. Communications, creativity, flexibility and accuracy are substantially improved by following a simple set of rules. A planning and scheduling program will work for you if you believe in it, make others in your project team realize its benefits, and make it an extension of your project cost control philosophy.

In-Space Crew-Collaborative Task Scheduling

NASA Technical Reports Server (NTRS)

Jaap, John; Meyer, Patrick; Davis, Elizabeth; Richardson, Lea

2006-01-01

As humans venture farther from Earth for longer durations, it will become essential for those on the journey to have significant control over the scheduling of their own activities as well as the activities of their companion systems and robots. However, the crew will not do all the scheduling; timelines will be the result of collaboration with ground personnel. Emerging technologies such as in-space message buses, delay-tolerant networks, and in-space internet will be the carriers on which the collaboration rides. Advances in scheduling technology, in the areas of task modeling, scheduling engines, and user interfaces will allow the crew to become virtual scheduling experts. New concepts of operations for producing the timeline will allow the crew and the ground support to collaborate while providing safeguards to ensure that the mission will be effectively accomplished without endangering the systems or personnel.

Interaural Level Difference Dependent Gain Control and Synaptic Scaling Underlying Binaural Computation

PubMed Central

Xiong, Xiaorui R.; Liang, Feixue; Li, Haifu; Mesik, Lukas; Zhang, Ke K.; Polley, Daniel B.; Tao, Huizhong W.; Xiao, Zhongju; Zhang, Li I.

2013-01-01

Binaural integration in the central nucleus of inferior colliculus (ICC) plays a critical role in sound localization. However, its arithmetic nature and underlying synaptic mechanisms remain unclear. Here, we showed in mouse ICC neurons that the contralateral dominance is created by a “push-pull”-like mechanism, with contralaterally dominant excitation and more bilaterally balanced inhibition. Importantly, binaural spiking response is generated apparently from an ipsilaterally-mediated scaling of contralateral response, leaving frequency tuning unchanged. This scaling effect is attributed to a divisive attenuation of contralaterally-evoked synaptic excitation onto ICC neurons with their inhibition largely unaffected. Thus, a gain control mediates the linear transformation from monaural to binaural spike responses. The gain value is modulated by interaural level difference (ILD) primarily through scaling excitation to different levels. The ILD-dependent synaptic scaling and gain adjustment allow ICC neurons to dynamically encode interaural sound localization cues while maintaining an invariant representation of other independent sound attributes. PMID:23972599

Development of Improved Graphical Displays for an Advanced Outage Control Center, Employing Human Factors Principles for Outage Schedule Management

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

St Germain, Shawn Walter; Farris, Ronald Keith; Thomas, Kenneth David

notifications; Provide real-time requirements monitoring; Maximize their collective situational awareness to improve decision-making; and Leverage macro data to better support resource allocation. INL has partnered with several commercial NPP utilities to develop a number of advanced outage management technologies. These outage management technologies have focused on both collaborative technologies for control centers and developing mobile technologies for NPP field workers. This report describes recent efforts made in developing a suite of outage technologies to support more effective schedule management. Currently, a master outage schedule is created months in advance using the plant’s existing scheduling software (e.g., Primavera P6). Typically, during the outage, the latest version of the schedule is printed at the beginning of each shift. INL and its partners are developing technologies that will have capabilities such as Automatic Schedule Updating, Automatic Pending Support Notifications, and the ability to allocate and schedule outage support task resources on a sub-hour basis (e.g., outage Micro-Scheduling). The remaining sections of this report describe in more detail the scheduling challenges that occur during outages, how the outage scheduling technologies INL is developing helps address those challenges, and the latest developments on this task (e.g., work accomplished to date and the path forward)« less

HUMAN RESPONDING ON RANDOM-INTERVAL SCHEDULES OF RESPONSE-COST PUNISHMENT: THE ROLE OF REDUCED REINFORCEMENT DENSITY

PubMed Central

Pietras, Cynthia J; Brandt, Andrew E; Searcy, Gabriel D

2010-01-01

An experiment with adult humans investigated the effects of response-contingent money loss (response-cost punishment) on monetary-reinforced responding. A yoked-control procedure was used to separate the effects on responding of the response-cost contingency from the effects of reduced reinforcement density. Eight adults pressed buttons for money on a three-component multiple reinforcement schedule. During baseline, responding in all components produced money gains according to a random-interval 20-s schedule. During punishment conditions, responding during the punishment component conjointly produced money losses according to a random-interval schedule. The value of the response-cost schedule was manipulated across conditions to systematically evaluate the effects on responding of response-cost frequency. Participants were assigned to one of two yoked-control conditions. For participants in the Yoked Punishment group, during punishment conditions money losses were delivered in the yoked component response independently at the same intervals that money losses were produced in the punishment component. For participants in the Yoked Reinforcement group, responding in the yoked component produced the same net earnings as produced in the punishment component. In 6 of 8 participants, contingent response cost selectively decreased response rates in the punishment component and the magnitude of the decrease was directly related to the punishment schedule value. Under punishment conditions, for participants in the Yoked Punishment group response rates in the yoked component also decreased, but the decrease was less than that observed in the punishment component, whereas for participants in the Yoked Reinforcement group response rates in the yoked component remained similar to rates in the no-punishment component. These results provide further evidence that contingent response cost functions similarly to noxious punishers in that it appears to suppress responding apart from

Concurrent Schedules of Positive and Negative Reinforcement: Differential-Impact and Differential-Outcomes Hypotheses

PubMed Central

Magoon, Michael A; Critchfield, Thomas S

2008-01-01

Considerable evidence from outside of operant psychology suggests that aversive events exert greater influence over behavior than equal-sized positive-reinforcement events. Operant theory is largely moot on this point, and most operant research is uninformative because of a scaling problem that prevents aversive events and those based on positive reinforcement from being directly compared. In the present investigation, humans' mouse-click responses were maintained on similarly structured, concurrent schedules of positive (money gain) and negative (avoidance of money loss) reinforcement. Because gains and losses were of equal magnitude, according to the analytical conventions of the generalized matching law, bias (log b ≠ 0) would indicate differential impact by one type of consequence; however, no systematic bias was observed. Further research is needed to reconcile this outcome with apparently robust findings in other literatures of superior behavior control by aversive events. In an incidental finding, the linear function relating log behavior ratio and log reinforcement ratio was steeper for concurrent negative and positive reinforcement than for control conditions involving concurrent positive reinforcement. This may represent the first empirical confirmation of a free-operant differential-outcomes effect predicted by contingency-discriminability theories of choice. PMID:18683609

Completable scheduling: An integrated approach to planning and scheduling

NASA Technical Reports Server (NTRS)

Gervasio, Melinda T.; Dejong, Gerald F.

1992-01-01

The planning problem has traditionally been treated separately from the scheduling problem. However, as more realistic domains are tackled, it becomes evident that the problem of deciding on an ordered set of tasks to achieve a set of goals cannot be treated independently of the problem of actually allocating resources to the tasks. Doing so would result in losing the robustness and flexibility needed to deal with imperfectly modeled domains. Completable scheduling is an approach which integrates the two problems by allowing an a priori planning module to defer particular planning decisions, and consequently the associated scheduling decisions, until execution time. This allows a completable scheduling system to maximize plan flexibility by allowing runtime information to be taken into consideration when making planning and scheduling decision. Furthermore, through the criteria of achievability placed on deferred decision, a completable scheduling system is able to retain much of the goal-directedness and guarantees of achievement afforded by a priori planning. The completable scheduling approach is further enhanced by the use of contingent explanation-based learning, which enables a completable scheduling system to learn general completable plans from example and improve its performance through experience. Initial experimental results show that completable scheduling outperforms classical scheduling as well as pure reactive scheduling in a simple scheduling domain.

ESSOPE: Towards S/C operations with reactive schedule planning

NASA Technical Reports Server (NTRS)

Wheadon, J.

1993-01-01

The ESSOPE is a prototype front-end tool running on a Sun workstation and interfacing to ESOC's MSSS spacecraft control system for the exchange of telecommand requests (to MSSS) and telemetry reports (from MSSS). ESSOPE combines an operations Planner-Scheduler, with a Schedule Execution Control function. Using an internal 'model' of the spacecraft, the Planner generates a schedule based on utilization requests for a variety of payload services by a community of Olympus users, and incorporating certain housekeeping operations. Conflicts based on operational constraints are automatically resolved, by employing one of several available strategies. The schedule is passed to the execution function which drives MSSS to perform it. When the schedule can no longer be met, either because the operator interferes (by delays or changes of requirements), or because ESSOPE has recognized some spacecraft anomalies, the Planner produces a modified schedule maintaining the on-going procedures as far as consistent with the new constraints or requirements.

When drugs in the same controlled substance schedule differ in real-world abuse, should they be differentiated in labeling?

PubMed

Dasgupta, Nabarun; Henningfield, Jack E; Ertischek, Michelle D; Schnoll, Sidney H

2011-12-01

The prescription drugs regulated in the most restrictive controlled substance schedule for those with an approved therapeutic use vary widely in their real world risk of abuse and harm. Opioid analgesics have the highest rates of abuse, overdose death, drug abuse treatment needs and societal costs in comparison to other Schedule II drugs. Stimulants for attention-deficit/hyperactivity disorders (ADHD) account for substantially lower rates of abuse, harm, and public health impact. The scheduling of drugs is determined by the World Health Organization, the United States Food and Drug Administration, and other regulatory agencies, through a quasi-public process that relies heavily on pre-marketing studies that are conducted in highly controlled clinical settings. We propose that it is increasingly in the interest of science-based regulation and public health to recognize and communicate differences among drugs based on their real-world abuse and public health harm using surveillance data. Appropriate differentiation through labeling of drugs that will likely remain in the same schedule could provide powerful incentives for drug development and research, would aid prescriber/patient decision making by informing them of real differences across drugs within a schedule, and may also contribute to public health efforts to reduce drug abuse. There are risks of course, that include inadvertent perceptions that drugs labeled to be lower in risk are not taken as seriously as others in the same category. Challenges such as these, however, can be overcome and should not serve as barriers to objective communications regarding a drug's actual risks. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

In-Space Crew-Collaborative Task Scheduling

NASA Technical Reports Server (NTRS)

Jaap, John; Meyer, Patrick; Davis, Elizabeth; Richardson, Lea

2006-01-01

As humans venture farther from earth for longer durations, it will become essential for those on the journey to have significant control over the scheduling of their own activities as well as the activities of their companion systems and robots. However, there are many reasons why the crew will not do all the scheduling; timelines will be the result of collaboration with ground personnel. Emerging technologies such as in-space message buses, delay-tolerant networks, and in-space internet will be the carriers on which the collaboration rides. Advances in scheduling technology, in the areas of task modeling, scheduling engines, and user interfaces will allow the crew to become virtual scheduling experts. New concepts of operations for producing the timeline will allow the crew and the ground support to collaborate while providing safeguards to ensure that the mission will be effectively accomplished without endangering the systems or personnel.

Responsive versus scheduled feeding for preterm infants.

PubMed

Watson, Julie; McGuire, William

2016-08-31

Feeding preterm infants in response to their hunger and satiation cues (responsive, cue-based, or infant-led feeding) rather than at scheduled intervals might enhance infants' and parents' experience and satisfaction, help in the establishment of independent oral feeding, increase nutrient intake and growth rates, and allow earlier hospital discharge. To assess the effect of a policy of feeding preterm infants on a responsive basis versus feeding prescribed volumes at scheduled intervals on growth rates, levels of parent satisfaction, and time to hospital discharge. We used the standard search strategy of the Cochrane Neonatal Review group to search the Cochrane Central Register of Controlled Trials (CENTRAL 2016, Issue 1), MEDLINE via PubMed (1966 to 17 February 2016), Embase (1980 to 17 February 2016), and CINAHL (1982 to 17 February 2016). We also searched clinical trials' databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. Randomised controlled trials (RCTs) or quasi-RCTs that compared a policy of feeding preterm infants on a responsive basis versus feeding at scheduled intervals. Two review authors assessed trial eligibility and risk of bias and undertook data extraction independently. We analysed the treatment effects in the individual trials and reported the risk ratio and risk difference for dichotomous data and mean difference (MD) for continuous data, with respective 95% confidence intervals (CIs). We used a fixed-effect model in meta-analyses and explored the potential causes of heterogeneity in sensitivity analyses. We assessed the quality of evidence at the outcome level using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. We found nine eligible RCTs including 593 infants in total. These trials compared responsive with scheduled interval regimens in preterm infants in the transition phase from intragastric tube to oral

THE EFFECTS OF FIXED VERSUS ESCALATING REINFORCEMENT SCHEDULES ON SMOKING ABSTINENCE

PubMed Central

Romanowich, Paul; Lamb, R. J.

2015-01-01

Studies indicate that when abstinence is initiated, escalating reinforcement schedules maintain continuous abstinence longer than fixed reinforcement schedules. However, these studies were conducted for shorter durations than most clinical trials and also resulted in larger reinforcer value for escalating participants during the 1st week of the experiment. We tested whether escalating reinforcement schedules maintained abstinence longer than fixed reinforcement schedules in a 12-week clinical trial. Smokers (146) were randomized to an escalating reinforcement schedule, a fixed reinforcement schedule, or a control condition. Escalating reinforcement participants received $5.00 for their first breath carbon monoxide (CO) sample <3 ppm, with a $0.50 increase for each consecutive sample. Fixed reinforcement participants received $19.75 for each breath CO sample <3 ppm. Control participants received payments only for delivering a breath CO sample. Similar proportions of escalating and fixed reinforcement participants met the breath CO criterion at least once. Escalating reinforcement participants maintained criterion breath CO levels longer than fixed reinforcement and control participants. Similar to previous short-term studies, escalating reinforcement schedules maintained longer durations of abstinence than fixed reinforcement schedules during a clinical trial. PMID:25640764

Effect of treatment in fractionated schedules with the combination of x-irradiation and six cytotoxic drugs on the RIF-1 tumor and normal mouse skin

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

Lelieveld, P.; Scoles, M.A.; Brown, J.M.

1985-01-01

RIF-1 tumors, implanted syngeneically in the gastrocnemius muscles of the right hind legs of C3H/Km mice, were treated either with X ray alone, drug alone, or drug and X ray combined. The drugs tested were bleomycin, BCNU, cis-diamminedichloro platinum, adriamycin, cyclophosphamide, and actinomycin-D. All drugs were administered either in the maximum tolerated dose or a dose that causes minimal tumor growth delay. Both drugs and X rays were administered either as a single dose or in five daily fractions. In addition to the single modality controls, seven different schedules of combined modalities were tested. Tumors were measured periodically after treatmentmore » in order that the day at which each tumor reached 4 times its initial cross-sectional area, i.e., its size at the time of treatment, could be determined. The effect of treatment on tumors was based upon excess growth delay (GD), i.e., T400% (treated)-T400% (untreated control). Treatment effects for the same combined modality schedules were also determined for normal skin, using the early skin reaction as an endpoint. Dose effect factors (DEF) were computed for all combined modality schedules and were based upon calculated radiation dose equivalents. We also calculated supra-additivity ratios, SR/sub I/ and SR/sub II/, therapeutic gain factors and adjusted therapeutic gain factors. The only drugs to produce significant supra-additivity with X rays were cis-Pt and cyclo.« less

78 FR 48193 - Final Adjusted Aggregate Production Quotas for Schedule I and II Controlled Substances and...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-07

... needs for the List I chemicals ephedrine, pseudoephedrine, and phenylpropanolamine, expressed in grams...,000 g Methamphetamine 3,912,500 g [987,500 grams of levo-desoxyephedrine for use in a non-controlled, non- prescription product; 2,863,750 grams for methamphetamine mostly for conversion to a schedule III...

Development of An Intelligent Flight Propulsion Control System

NASA Technical Reports Server (NTRS)

Calise, A. J.; Rysdyk, R. T.; Leonhardt, B. K.

1999-01-01

The initial design and demonstration of an Intelligent Flight Propulsion and Control System (IFPCS) is documented. The design is based on the implementation of a nonlinear adaptive flight control architecture. This initial design of the IFPCS enhances flight safety by using propulsion sources to provide redundancy in flight control. The IFPCS enhances the conventional gain scheduled approach in significant ways: (1) The IFPCS provides a back up flight control system that results in consistent responses over a wide range of unanticipated failures. (2) The IFPCS is applicable to a variety of aircraft models without redesign and,(3) significantly reduces the laborious research and design necessary in a gain scheduled approach. The control augmentation is detailed within an approximate Input-Output Linearization setting. The availability of propulsion only provides two control inputs, symmetric and differential thrust. Earlier Propulsion Control Augmentation (PCA) work performed by NASA provided for a trajectory controller with pilot command input of glidepath and heading. This work is aimed at demonstrating the flexibility of the IFPCS in providing consistency in flying qualities under a variety of failure scenarios. This report documents the initial design phase where propulsion only is used. Results confirm that the engine dynamics and associated hard nonlineaaities result in poor handling qualities at best. However, as demonstrated in simulation, the IFPCS is capable of results similar to the gain scheduled designs of the NASA PCA work. The IFPCS design uses crude estimates of aircraft behaviour. The adaptive control architecture demonstrates robust stability and provides robust performance. In this work, robust stability means that all states, errors, and adaptive parameters remain bounded under a wide class of uncertainties and input and output disturbances. Robust performance is measured in the quality of the tracking. The results demonstrate the flexibility of

Adaptive wing static aeroelastic roll control

NASA Astrophysics Data System (ADS)

Ehlers, Steven M.; Weisshaar, Terrence A.

1993-09-01

Control of the static aeroelastic characteristics of a swept uniform wing in roll using an adaptive structure is examined. The wing structure is modeled as a uniform beam with bending and torsional deformation freedom. Aerodynamic loads are obtained from strip theory. The structure model includes coefficients representing torsional and bending actuation provided by embedded piezoelectric material layers. The wing is made adaptive by requiring the electric field applied to the piezoelectric material layers to be proportional to the wing root loads. The proportionality factor, or feedback gain, is used to control static aeroelastic rolling properties. Example wing configurations are used to illustrate the capabilities of the adaptive structure. The results show that rolling power, damping-in-roll and aileron effectiveness can be controlled by adjusting the feedback gain. And that dynamic pressure affects the gain required. Gain scheduling can be used to set and maintain rolling properties over a range of dynamic pressures. An adaptive wing provides a method for active aeroelastic tailoring of structural response to meet changing structural performance requirements during a roll maneuver.

Observation Scheduling System

NASA Technical Reports Server (NTRS)

Chien, Steve A.; Tran, Daniel Q.; Rabideau, Gregg R.; Schaffer, Steven R.

2011-01-01

Software has been designed to schedule remote sensing with the Earth Observing One spacecraft. The software attempts to satisfy as many observation requests as possible considering each against spacecraft operation constraints such as data volume, thermal, pointing maneuvers, and others. More complex constraints such as temperature are approximated to enable efficient reasoning while keeping the spacecraft within safe limits. Other constraints are checked using an external software library. For example, an attitude control library is used to determine the feasibility of maneuvering between pairs of observations. This innovation can deal with a wide range of spacecraft constraints and solve large scale scheduling problems like hundreds of observations and thousands of combinations of observation sequences.

32 CFR 229.21 - Surveys and schedules.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 2 2012-07-01 2012-07-01 false Surveys and schedules. 229.21 Section 229.21...) MISCELLANEOUS PROTECTION OF ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 229.21 Surveys and schedules. (a... Tennessee Valley Authority will develop plans for surveying lands under each agency's control to determine...

18 CFR 1312.21 - Surveys and schedules.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Surveys and schedules... OF ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 1312.21 Surveys and schedules. (a) The Secretaries... Authority will develop plans for surveying lands under each agency's control to determine the nature and...

32 CFR 229.21 - Surveys and schedules.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 2 2010-07-01 2010-07-01 false Surveys and schedules. 229.21 Section 229.21...) MISCELLANEOUS PROTECTION OF ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 229.21 Surveys and schedules. (a... Tennessee Valley Authority will develop plans for surveying lands under each agency's control to determine...

32 CFR 229.21 - Surveys and schedules.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 32 National Defense 2 2014-07-01 2014-07-01 false Surveys and schedules. 229.21 Section 229.21...) MISCELLANEOUS PROTECTION OF ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 229.21 Surveys and schedules. (a... Tennessee Valley Authority will develop plans for surveying lands under each agency's control to determine...

18 CFR 1312.21 - Surveys and schedules.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Surveys and schedules... OF ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 1312.21 Surveys and schedules. (a) The Secretaries... Authority will develop plans for surveying lands under each agency's control to determine the nature and...

18 CFR 1312.21 - Surveys and schedules.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Surveys and schedules... OF ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 1312.21 Surveys and schedules. (a) The Secretaries... Authority will develop plans for surveying lands under each agency's control to determine the nature and...

18 CFR 1312.21 - Surveys and schedules.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Surveys and schedules... OF ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 1312.21 Surveys and schedules. (a) The Secretaries... Authority will develop plans for surveying lands under each agency's control to determine the nature and...

High Efficiency Automatic-Power-Controlled and Gain-Clamped EDFA for Broadband Passive Optical Networking Systems

NASA Astrophysics Data System (ADS)

Shen, Jyi-Lai; Wei, Shui-Ken; Lin, Chin-Yuan; Iong Li, Ssu; Huang, Chih-Chuan

2010-04-01

The configuration of a simple improved high efficiency automatic-power-controlled and gain-clamped EDFA (APC-GC-EDFA) for broadband passive optical networking systems (BPON) is presented here. In order to compensate the phase and amplitude variation due to the different distance between the optical line terminal (OLT) and optical network units (ONU), the APC-GC-EDFA need to be employed. A single 980 nm laser module is employed as the primary pump. To extend the bandwidth, all C-band ASE is recycled as the secondary pump to enhance the gain efficiency. An electrical feedback circuit is used as a multi-wavelength channel transmitter monitor for the automatic power control to improve the gain-flattened flatness for stable amplification. The experimental results prove that the EDFA system can provide flatter clamped gain in both C-band and L-band configurations. The gain flatness wavelength ranging from 1530 to 1610 nm is within 32.83 ± 0.64 dB, i.e. below 1.95 %. The gains are clamped at 33.85 ± 0.65 dB for the input signal power of -40 dBm to -10 dBm. The range of noise figure is between 6.37 and 6.56, which is slightly lower compared to that of unclamped amplifiers. This will be very useful for measuring the gain flatness of APC-GC-EDFA. Finally, we have also demonstrated the records of the overall simultaneous dynamics measurements for the new system stabilization. The carrier to noise ratio (CNR) is 49.5 to 50.8 dBc which is above the National Television System Committee (NTSC) standard of 43 dBc, and both composite second order (CSO) 69.2 to 71.5 dBc and composite triple beat (CTB) of 69.8 to 72.2 dBc are above 53 dBc. The recorded corresponding rise-time of 1.087 ms indicates that the system does not exhibit any overshoot of gain or ASE variation due to the signal at the beginning of the pulse.

The Effect of a Federal Controlled Substance Act Schedule Change on Hydrocodone Combination Products Claims in a Medicaid Population.

PubMed

Tran, Stephanie; Lavitas, Pavel; Stevens, Karen; Greenwood, Bonnie C; Clements, Karen; Alper, Caroline J; Lenz, Kimberly; Price, Mylissa; Hydery, Tasmina; Arnold, Jennifer L; Takeshita, Mito; Bacon, Rachel; Peristere, Justin P; Jeffrey, Paul L

2017-05-01

In 2012, hydrocodone combination products (HCPs) were the most prescribed medications in the United States. Under the Controlled Substance Act of 1970, hydrocodone alone was classified as a Schedule II drug, while HCPs were classified as Schedule III, indicating a lower risk for abuse and misuse. However, according to a Drug Enforcement Agency analysis, the addition of nonopioids has not been shown to diminish abuse potential of hydrocodone. In response to concerns for drug abuse and overdose, the Drug Enforcement Agency rescheduled HCPs to Schedule II in October 2014, with the intent of limiting overprescribing and increasing awareness of their abuse potential. However, it is unknown whether this has affected the overall claims for HCPs in a Medicaid population. To (a) compare the trend in HCP prescription claims with select non-HCP (opioid and nonopioid) analgesic claims before and after the HCP schedule change in the Massachusetts Medicaid fee-for-service/Primary Care Clinician plan population and (b) identify if there was a change in HCP new start member and claim characteristics before and after the HCP schedule change. This quasi-experimental, retrospective study used enrollment and pharmacy claims data to evaluate all members in the study population 1 year before and after the HCP schedule change. The number of claims for HCPs and select non-HCP analgesics was reported as the monthly rate per total population, and an interrupted time series analysis compared the change in the monthly rate of claims across groups. Members with 1 or more pharmacy claims for a new HCP prescription during a 5-month period before or after the HCP schedule change were analyzed to determine member demographics (age, gender, and number of claims) and claim characteristics (average daily dose, average quantity per claim, and days supply). The rate of HCP claims increased before and decreased after the HCP schedule change. Controlling for the trend during the period before the HCP

78 FR 40186 - Proposed Aggregate Production Quotas for Schedule I and II Controlled Substances and Proposed...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-03

... phenylpropanolamine, expressed in grams of anhydrous acid or base, be established as follows: Proposed 2014 Basic... grams of levo-desoxyephedrine for use in a non-controlled, non-prescription product; 2,600,000 grams for methamphetamine mostly for conversion to a schedule III product; and 61,375 grams for methamphetamine (for sale...

36 CFR 296.21 - Surveys and Schedules.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false Surveys and Schedules. 296.21... ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 296.21 Surveys and Schedules. (a) The Secretaries of the Interior... for surveying lands under each agency's control to determine the nature and extent of archaeological...

36 CFR 296.21 - Surveys and Schedules.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Surveys and Schedules. 296.21... ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 296.21 Surveys and Schedules. (a) The Secretaries of the Interior... for surveying lands under each agency's control to determine the nature and extent of archaeological...

36 CFR 296.21 - Surveys and Schedules.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Surveys and Schedules. 296.21... ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 296.21 Surveys and Schedules. (a) The Secretaries of the Interior... for surveying lands under each agency's control to determine the nature and extent of archaeological...

36 CFR 296.21 - Surveys and Schedules.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Surveys and Schedules. 296.21... ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 296.21 Surveys and Schedules. (a) The Secretaries of the Interior... for surveying lands under each agency's control to determine the nature and extent of archaeological...

An optimal output feedback gain variation scheme for the control of plants exhibiting gross parameter changes

NASA Technical Reports Server (NTRS)

Moerder, Daniel D.

1987-01-01

A concept for optimally designing output feedback controllers for plants whose dynamics exhibit gross changes over their operating regimes was developed. This was to formulate the design problem in such a way that the implemented feedback gains vary as the output of a dynamical system whose independent variable is a scalar parameterization of the plant operating point. The results of this effort include derivation of necessary conditions for optimality for the general problem formulation, and for several simplified cases. The question of existence of a solution to the design problem was also examined, and it was shown that the class of gain variation schemes developed are capable of achieving gain variation histories which are arbitrarily close to the unconstrained gain solution for each point in the plant operating range. The theory was implemented in a feedback design algorithm, which was exercised in a numerical example. The results are applicable to the design of practical high-performance feedback controllers for plants whose dynamics vary significanly during operation. Many aerospace systems fall into this category.

Affirmative Action: The Scheduled Castes and the Scheduled Tribes.

ERIC Educational Resources Information Center

Sivaramayya, B.

This paper considers Indian affirmative action policies that provide reservations (quotas) in favor of two disadvantaged groups, the scheduled castes and the scheduled tribes. First, definitions and background are presented. The scheduled castes ("untouchables") are said to suffer from social segregation, and the scheduled tribes from…

Design and evaluation of controls for drift, video gain, and color balance in spaceborne facsimile cameras

NASA Technical Reports Server (NTRS)

Katzberg, S. J.; Kelly, W. L., IV; Rowland, C. W.; Burcher, E. E.

1973-01-01

The facsimile camera is an optical-mechanical scanning device which has become an attractive candidate as an imaging system for planetary landers and rovers. This paper presents electronic techniques which permit the acquisition and reconstruction of high quality images with this device, even under varying lighting conditions. These techniques include a control for low frequency noise and drift, an automatic gain control, a pulse-duration light modulation scheme, and a relative spectral gain control. Taken together, these techniques allow the reconstruction of radiometrically accurate and properly balanced color images from facsimile camera video data. These techniques have been incorporated into a facsimile camera and reproduction system, and experimental results are presented for each technique and for the complete system.

Floating-point scaling technique for sources separation automatic gain control

NASA Astrophysics Data System (ADS)

Fermas, A.; Belouchrani, A.; Ait-Mohamed, O.

2012-07-01

Based on the floating-point representation and taking advantage of scaling factor indetermination in blind source separation (BSS) processing, we propose a scaling technique applied to the separation matrix, to avoid the saturation or the weakness in the recovered source signals. This technique performs an automatic gain control in an on-line BSS environment. We demonstrate the effectiveness of this technique by using the implementation of a division-free BSS algorithm with two inputs, two outputs. The proposed technique is computationally cheaper and efficient for a hardware implementation compared to the Euclidean normalisation.

75 FR 42831 - Proposed Collection; Comment Request for Form 1065, Schedule C, Schedule D, Schedule K-1...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-22

... Income, Credits, Deductions and Other Items), Schedule L (Balance Sheets per Books), Schedule M-1..., Deductions, etc. (Schedule K-1), Balance Sheets per Books (Schedule L), Reconciliation of Income (Loss) per...

Visual signal detection in structured backgrounds. II. Effects of contrast gain control, background variations, and white noise

NASA Technical Reports Server (NTRS)

Eckstein, M. P.; Ahumada, A. J. Jr; Watson, A. B.

1997-01-01

Studies of visual detection of a signal superimposed on one of two identical backgrounds show performance degradation when the background has high contrast and is similar in spatial frequency and/or orientation to the signal. To account for this finding, models include a contrast gain control mechanism that pools activity across spatial frequency, orientation and space to inhibit (divisively) the response of the receptor sensitive to the signal. In tasks in which the observer has to detect a known signal added to one of M different backgrounds grounds due to added visual noise, the main sources of degradation are the stochastic noise in the image and the suboptimal visual processing. We investigate how these two sources of degradation (contrast gain control and variations in the background) interact in a task in which the signal is embedded in one of M locations in a complex spatially varying background (structured background). We use backgrounds extracted from patient digital medical images. To isolate effects of the fixed deterministic background (the contrast gain control) from the effects of the background variations, we conduct detection experiments with three different background conditions: (1) uniform background, (2) a repeated sample of structured background, and (3) different samples of structured background. Results show that human visual detection degrades from the uniform background condition to the repeated background condition and degrades even further in the different backgrounds condition. These results suggest that both the contrast gain control mechanism and the background random variations degrade human performance in detection of a signal in a complex, spatially varying background. A filter model and added white noise are used to generate estimates of sampling efficiencies, an equivalent internal noise, an equivalent contrast-gain-control-induced noise, and an equivalent noise due to the variations in the structured background.

32 CFR 169a.8 - Inventory and review schedule (Report Control Symbol DD-P&L(A)).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 1 2011-07-01 2011-07-01 false Inventory and review schedule (Report Control Symbol DD-P&L(A)). 169a.8 Section 169a.8 National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE DEFENSE CONTRACTING COMMERCIAL ACTIVITIES PROGRAM PROCEDURES Procedures § 169a.8 Inventory...

32 CFR 169a.8 - Inventory and review schedule (Report Control Symbol DD-P&L(A)).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 1 2013-07-01 2013-07-01 false Inventory and review schedule (Report Control Symbol DD-P&L(A)). 169a.8 Section 169a.8 National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE DEFENSE CONTRACTING COMMERCIAL ACTIVITIES PROGRAM PROCEDURES Procedures § 169a.8 Inventory...

32 CFR 169a.8 - Inventory and review schedule (Report Control Symbol DD-P&L(A)).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 1 2010-07-01 2010-07-01 false Inventory and review schedule (Report Control Symbol DD-P&L(A)). 169a.8 Section 169a.8 National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE DEFENSE CONTRACTING COMMERCIAL ACTIVITIES PROGRAM PROCEDURES Procedures § 169a.8 Inventory...

Scheduling lessons learned from the Autonomous Power System

NASA Technical Reports Server (NTRS)

Ringer, Mark J.

1992-01-01

The Autonomous Power System (APS) project at NASA LeRC is designed to demonstrate the applications of integrated intelligent diagnosis, control, and scheduling techniques to space power distribution systems. The project consists of three elements: the Autonomous Power Expert System (APEX) for Fault Diagnosis, Isolation, and Recovery (FDIR); the Autonomous Intelligent Power Scheduler (AIPS) to efficiently assign activities start times and resources; and power hardware (Brassboard) to emulate a space-based power system. The AIPS scheduler was tested within the APS system. This scheduler is able to efficiently assign available power to the requesting activities and share this information with other software agents within the APS system in order to implement the generated schedule. The AIPS scheduler is also able to cooperatively recover from fault situations by rescheduling the affected loads on the Brassboard in conjunction with the APEX FDIR system. AIPS served as a learning tool and an initial scheduling testbed for the integration of FDIR and automated scheduling systems. Many lessons were learned from the AIPS scheduler and are now being integrated into a new scheduler called SCRAP (Scheduler for Continuous Resource Allocation and Planning). This paper will service three purposes: an overview of the AIPS implementation, lessons learned from the AIPS scheduler, and a brief section on how these lessons are being applied to the new SCRAP scheduler.

Automation Improves Schedule Quality and Increases Scheduling Efficiency for Residents.

PubMed

Perelstein, Elizabeth; Rose, Ariella; Hong, Young-Chae; Cohn, Amy; Long, Micah T

2016-02-01

Medical resident scheduling is difficult due to multiple rules, competing educational goals, and ever-evolving graduate medical education requirements. Despite this, schedules are typically created manually, consuming hours of work, producing schedules of varying quality, and yielding negative consequences for resident morale and learning. To determine whether computerized decision support can improve the construction of residency schedules, saving time and improving schedule quality. The Optimized Residency Scheduling Assistant was designed by a team from the University of Michigan Department of Industrial and Operations Engineering. It was implemented in the C.S. Mott Children's Hospital Pediatric Emergency Department in the 2012-2013 academic year. The 4 metrics of schedule quality that were compared between the 2010-2011 and 2012-2013 academic years were the incidence of challenging shift transitions, the incidence of shifts following continuity clinics, the total shift inequity, and the night shift inequity. All scheduling rules were successfully incorporated. Average schedule creation time fell from 22 to 28 hours to 4 to 6 hours per month, and 3 of 4 metrics of schedule quality significantly improved. For the implementation year, the incidence of challenging shift transitions decreased from 83 to 14 (P < .01); the incidence of postclinic shifts decreased from 72 to 32 (P < .01); and the SD of night shifts dropped by 55.6% (P < .01). This automated shift scheduling system improves the current manual scheduling process, reducing time spent and improving schedule quality. Embracing such automated tools can benefit residency programs with shift-based scheduling needs.

A randomised controlled trial comparing two schedules of antenatal visits: the antenatal care project.

PubMed Central

Sikorski, J.; Wilson, J.; Clement, S.; Das, S.; Smeeton, N.

1996-01-01

OBJECTIVE--To compare the clinical and psychological effectiveness of the traditional British antenatal visit schedule (traditional care) with a reduced schedule of visits (new style care) for low risk women, together with maternal and professional satisfaction with care. DESIGN--Randomised controlled trial. SETTING--Places in south east London providing antenatal care for women receiving shared care and planning to deliver in one of three hospitals or at home. SUBJECT--2794 women at low risk fulfilling the trial's inclusion criteria between June 1993 and July 1994. MAIN OUTCOME MEASURES--Measures of fetal and maternal morbidity, health service use, psychosocial outcomes, and maternal and professional satisfaction. RESULTS--Pregnant women allocated to new style care had fewer day admissions (0.8 v 1.0; P=0.002) and ultrasound scans (1.6 v 1.7; P=0.003) and were less often suspected of carrying fetuses that were small for gestational age (odds ratio 0.73; 95% confidence interval 0.54 to 0.99). They also had some poorer psychosocial outcomes; for example, they were more worried about fetal wellbeing antenatally and coping with the baby postnatally, and they had more negative attitudes to their babies, both in pregnancy and postnatally. These women were also more dissatisfied with the number of visits they received (odds ratio 2.50; 2.00 to 3.11). CONCLUSIONS--Patterns of antenatal care involving fewer routine visits for women at low risk may lead to reduced psychosocial effectiveness and dissatisfaction with frequency of visits. The number of antenatal day admissions and ultrasound scans performed may also be reduced. For the variables reported, the visit schedules studied are similar in their clinical effectiveness. Uncertainty remains as to the clinical effectiveness of reduced visit schedules for rare pregnancy problems. PMID:8595286

Scheduling logic for Miles-In-Trail traffic management

NASA Technical Reports Server (NTRS)

Synnestvedt, Robert G.; Swenson, Harry; Erzberger, Heinz

1995-01-01

This paper presents an algorithm which can be used for scheduling arrival air traffic in an Air Route Traffic Control Center (ARTCC or Center) entering a Terminal Radar Approach Control (TRACON) Facility . The algorithm aids a Traffic Management Coordinator (TMC) in deciding how to restrict traffic while the traffic expected to arrive in the TRACON exceeds the TRACON capacity. The restrictions employed fall under the category of Miles-in-Trail, one of two principal traffic separation techniques used in scheduling arrival traffic . The algorithm calculates aircraft separations for each stream of aircraft destined to the TRACON. The calculations depend upon TRACON characteristics, TMC preferences, and other parameters adapted to the specific needs of scheduling traffic in a Center. Some preliminary results of traffic simulations scheduled by this algorithm are presented, and conclusions are drawn as to the effectiveness of using this algorithm in different traffic scenarios.

Influence of a scheduled-waiting task on EMG reactivity and oral habits among facial pain patients and no-pain controls.

PubMed

Nicholson, R A; Townsend, D R; Gramling, S E

2000-12-01

Recent research has strongly implicated the role of psychological stress in the development of temporomandibular disorders (TMD). It is widely reported that oral habits (e.g., teeth grinding) probably provide a behavioral link between stress and the development of TMD symptomatology. Extrapolation of research in the field of adjunctive behavior to the TMD disorders suggests that oral behaviors may develop conjointly with fixed-time (FT) stimulus presentation. The current experiment extended previous research examining this possibility by assessing the influence of experimental stress on masseter EMG and oral habits among persons who met broadband criteria for TMD and no-pain controls. Oral habit activity was assessed via self-report questionnaire whereas masseter muscle activity was measured continuously via electromyography across four phases (Adaptation, Free-Play, Scheduled-Play, Recovery). The Scheduled-Play phase was designed as a stress-reactivity task that included an FT schedule. Results indicated that, consistent with the stress-reactivity model, the Scheduled-Play phase resulted in a significant increase in masseter EMG levels relative to Free-Play and Adaptation, and that this effect was significantly larger for the TMD group relative to controls. The results suggest an adjunctive behavior effect although the effect was not specific to those with facial pain. Oral habit data showed a significant phase effect with oral habits that was significantly higher during the Scheduled-Play phase relative to Adaptation. The findings are the impetus for further study regarding the mechanisms whereby oral habits are developed and maintained despite their painful consequences.

Experiments with a decision-theoretic scheduler

NASA Technical Reports Server (NTRS)

Hansson, Othar; Holt, Gerhard; Mayer, Andrew

1992-01-01

This paper describes DTS, a decision-theoretic scheduler designed to employ state-of-the-art probabilistic inference technology to speed the search for efficient solutions to constraint-satisfaction problems. Our approach involves assessing the performance of heuristic control strategies that are normally hard-coded into scheduling systems, and using probabilistic inference to aggregate this information in light of features of a given problem. BPS, the Bayesian Problem-Solver, introduced a similar approach to solving single-agent and adversarial graph search problems, yielding orders-of-magnitude improvement over traditional techniques. Initial efforts suggest that similar improvements will be realizable when applied to typical constraint-satisfaction scheduling problems.

A new task scheduling algorithm based on value and time for cloud platform

NASA Astrophysics Data System (ADS)

Kuang, Ling; Zhang, Lichen

2017-08-01

Tasks scheduling, a key part of increasing resource utilization and enhancing system performance, is a never outdated problem especially in cloud platforms. Based on the value density algorithm of the real-time task scheduling system and the character of the distributed system, the paper present a new task scheduling algorithm by further studying the cloud technology and the real-time system: Least Level Value Density First (LLVDF). The algorithm not only introduces some attributes of time and value for tasks, it also can describe weighting relationships between these properties mathematically. As this feature of the algorithm, it can gain some advantages to distinguish between different tasks more dynamically and more reasonably. When the scheme was used in the priority calculation of the dynamic task scheduling on cloud platform, relying on its advantage, it can schedule and distinguish tasks with large amounts and many kinds more efficiently. The paper designs some experiments, some distributed server simulation models based on M/M/C model of queuing theory and negative arrivals, to compare the algorithm against traditional algorithm to observe and show its characters and advantages.

Real Time Energy Management Control Strategies for Hybrid Powertrains

NASA Astrophysics Data System (ADS)

Zaher, Mohamed Hegazi Mohamed

In order to improve fuel efficiency and reduce emissions of mobile vehicles, various hybrid power-train concepts have been developed over the years. This thesis focuses on embedded control of hybrid powertrain concepts for mobile vehicle applications. Optimal robust control approach is used to develop a real time energy management strategy for continuous operations. The main idea is to store the normally wasted mechanical regenerative energy in energy storage devices for later usage. The regenerative energy recovery opportunity exists in any condition where the speed of motion is in opposite direction to the applied force or torque. This is the case when the vehicle is braking, decelerating, or the motion is driven by gravitational force, or load driven. There are three main concepts for regernerative energy storing devices in hybrid vehicles: electric, hydraulic, and flywheel. The real time control challenge is to balance the system power demand from the engine and the hybrid storage device, without depleting the energy storage device or stalling the engine in any work cycle, while making optimal use of the energy saving opportunities in a given operational, often repetitive cycle. In the worst case scenario, only engine is used and hybrid system completely disabled. A rule based control is developed and tuned for different work cycles and linked to a gain scheduling algorithm. A gain scheduling algorithm identifies the cycle being performed by the machine and its position via GPS, and maps them to the gains.

Voluntary Fasting to Control Post-Ramadan Weight Gain among Overweight and Obese Women

PubMed Central

Ismail, Suriani; Shamsuddin, Khadijah; Latiff, Khalib A.; Saad, Hazizi A.; Majid, Latifah A.; Othman, Fadlan M.

2015-01-01

Objectives: This study aimed to examine the effectiveness of an Islamic voluntary fasting intervention to control post-Ramadan weight gain. Methods: This study was conducted between July and November 2011. Two weight loss intervention programmes were developed and implemented among groups of overweight or obese Malay women living in the Malaysian cities of Putrajaya and Seremban: a standard programme promoting control of food intake according to national dietary guidelines (group B) and a faith-based programme promoting voluntary fasting in addition to the standard programme (group A). Participants’ dietary practices (i.e., voluntary fasting practices, frequency of fruit/vegetable consumption per week and quantity of carbohydrates/protein consumed per day), body mass index (BMI), blood pressure, fasting blood high-density lipoprotein cholesterol (HDL-C) and total cholesterol (TC):HDL-C ratio were assessed before Ramadan and three months post-Ramadan. Results: Voluntary fasting practices increased only in group A (P <0.01). Additionally, the quantity of protein/carbohydrates consumed per day, mean diastolic pressure and TC:HDL-C ratio decreased only in group A (P <0.01, 0.05, 0.02 and <0.01, respectively). Frequency of fruit/vegetable consumption per week, as well as HDL-C levels, increased only in group A (P = 0.03 and <0.01, respectively). Although changes in BMI between the groups was not significant (P = 0.08), BMI decrease among participants in group A was significant (P <0.01). Conclusion: Control of post-Ramadan weight gain was more evident in the faith-based intervention group. Healthcare providers should consider faith-based interventions to encourage weight loss during Ramadan and to prevent post-Ramadan weight gain among patients. PMID:25685394

Dedicated heterogeneous node scheduling including backfill scheduling

DOEpatents

Wood, Robert R [Livermore, CA; Eckert, Philip D [Livermore, CA; Hommes, Gregg [Pleasanton, CA

2006-07-25

A method and system for job backfill scheduling dedicated heterogeneous nodes in a multi-node computing environment. Heterogeneous nodes are grouped into homogeneous node sub-pools. For each sub-pool, a free node schedule (FNS) is created so that the number of to chart the free nodes over time. For each prioritized job, using the FNS of sub-pools having nodes useable by a particular job, to determine the earliest time range (ETR) capable of running the job. Once determined for a particular job, scheduling the job to run in that ETR. If the ETR determined for a lower priority job (LPJ) has a start time earlier than a higher priority job (HPJ), then the LPJ is scheduled in that ETR if it would not disturb the anticipated start times of any HPJ previously scheduled for a future time. Thus, efficient utilization and throughput of such computing environments may be increased by utilizing resources otherwise remaining idle.

Scheduling and control strategies for the departure problem in air traffic control

NASA Astrophysics Data System (ADS)

Bolender, Michael Alan

Two problems relating to the departure problem in air traffic control automation are examined. The first problem that is addressed is the scheduling of aircraft for departure. The departure operations at a major US hub airport are analyzed, and a discrete event simulation of the departure operations is constructed. Specifically, the case where there is a single departure runway is considered. The runway is fed by two queues of aircraft. Each queue, in turn, is fed by a single taxiway. Two salient areas regarding scheduling are addressed. The first is the construction of optimal departure sequences for the aircraft that are queued. Several greedy search algorithms are designed to minimize the total time to depart a set of queued aircraft. Each algorithm has a different set of heuristic rules to resolve situations within the search space whenever two branches of the search tree with equal edge costs are encountered. These algorithms are then compared and contrasted with a genetic search algorithm in order to assess the performance of the heuristics. This is done in the context of a static departure problem where the length of the departure queue is fixed. A greedy algorithm which deepens the search whenever two branches of the search tree with non-unique costs are encountered is shown to outperform the other heuristic algorithms. This search strategy is then implemented in the discrete event simulation. A baseline performance level is established, and a sensitivity analysis is performed by implementing changes in traffic mix, routing, and miles-in-trail restrictions for comparison. It is concluded that to minimize the average time spent in the queue for different traffic conditions, a queue assignment algorithm is needed to maintain an even balance of aircraft in the queues. A necessary consideration is to base queue assignment upon traffic management restrictions such as miles-in-trail constraints. The second problem addresses the technical challenges associated

Maternal Locus of Control and Developmental Gain Demonstrated by High Risk Infants: A Longitudinal Analysis.

ERIC Educational Resources Information Center

Maisto, Albert A.; German, Michael L.

1981-01-01

Short- and long-term effects of a parent-infant training program for biologically handicapped infants was evaluated in terms of maternal locus of control. Results indicated that maternal locus of control accounted for a substantial portion of the variance in the infants' developmental gains following the program intervention period. (Author/RH)

Physical assistance devices in complex motor skill learning: benefits of a self-controlled practice schedule.

PubMed

Wulf, G; Toole, T

1999-09-01

This study examines the effects of a self-controlled use of physical assistance devices on learning a complex motor skill (i.e., producing slalom-type movements on a ski simulator). Physical assistance was provided by ski poles. One group of learners (self-control) was provided with the poles whenever they requested them, whereas another (yoked) group had no influence on the pole/no-pole schedule. While there were no group differences during the practice phase (Days 1 and 2), clear group differences emerged in the retention test without poles (Day 3). The self-control group produced significantly larger amplitudes than the yoked group. These results extend previous findings by showing learning advantages of the self-controlled use of physical assistance devices in complex motor skill learning.

The moderating effect of control over work scheduling and overtime on the relationship between workload demands and perceived job risk.

PubMed

Näswall, Katharina; Burt, Christopher D B; Pearce, Megan

2015-01-01

This study investigated the impact of workload demands on perceived job risk using the Job Demand-Control model as a research framework. The primary objective was to test the hypothesis that employee control over work scheduling and overtime would moderate the relationship between workload demands and perceived job risk. Ninety-six participants working in a variety of industries completed measures of workload demands, and of control over work scheduling and overtime, and a measure of perceived job risk. Workload demands predicted higher perceptions of job risk. However, the results also suggest that control over overtime moderated this relationship, where those with the combination of high workload demands and low control over overtime reported higher levels of perceived risk. The results indicate that the JDC model is applicable to safety research. The results suggest that employee control over workload demands is an important variable to consider in terms of managing workplace safety. The present study also points to important areas for future research to explore in order to further understand the connection between demands and safety.

A Comparison of Escalating versus Fixed Reinforcement Schedules on Undergraduate Quiz Taking

ERIC Educational Resources Information Center

Mahoney, Amanda

2017-01-01

Drug abstinence studies indicate that escalating reinforcement schedules maintain abstinence for longer periods than fixed reinforcement schedules. The current study evaluated whether escalating reinforcement schedules would maintain more quiz taking than fixed reinforcement schedules. During baseline and for the control group, bonus points were…

Comparing Learning Gains: Audio Versus Text-based Instructor Communication in a Blended Online Learning Environment

NASA Astrophysics Data System (ADS)

Shimizu, Dominique

Though blended course audio feedback has been associated with several measures of course satisfaction at the postsecondary and graduate levels compared to text feedback, it may take longer to prepare and positive results are largely unverified in K-12 literature. The purpose of this quantitative study was to investigate the time investment and learning impact of audio communications with 228 secondary students in a blended online learning biology unit at a central Florida public high school. A short, individualized audio message regarding the student's progress was given to each student in the audio group; similar text-based messages were given to each student in the text-based group on the same schedule; a control got no feedback. A pretest and posttest were employed to measure learning gains in the three groups. To compare the learning gains in two types of feedback with each other and to no feedback, a controlled, randomized, experimental design was implemented. In addition, the creation and posting of audio and text feedback communications were timed in order to assess whether audio feedback took longer to produce than text only feedback. While audio feedback communications did take longer to create and post, there was no difference between learning gains as measured by posttest scores when student received audio, text-based, or no feedback. Future studies using a similar randomized, controlled experimental design are recommended to verify these results and test whether the trend holds in a broader range of subjects, over different time frames, and using a variety of assessment types to measure student learning.

Flight experience with manually controlled unconventional aircraft motions

NASA Technical Reports Server (NTRS)

Barfield, A. F.

1978-01-01

A modified YF-16 aircraft was used to flight demonstrate decoupled modes under the USAF Fighter Control Configured Vehicle (CCV) Program. The direct force capabilities were used to implement seven manually controlled unconventional modes on the aircraft, allowing flat turns, decoupled normal acceleration control, independent longitudinal and lateral translations, uncoupled elevation and azimuth aiming, and blended direct lift. This paper describes the design, development, and flight testing of these control modes. The need for task-tailored mode authorities, gain-scheduling and selected closed-loop design is discussed.

Food-deprivation effects on punished schedule-induced drinking in rats.

PubMed Central

Lamas, E; Pellón, R

1995-01-01

Food-deprived rats (at 80% of their free-feeding weights) were exposed to a fixed-time 60-s schedule of food-pellet presentation and developed schedule-induced drinking. Lick-dependent signaled delays (10 s) to food presentation led to decreased drinking, which recovered when the signaled delays were discontinued. A major effect of this punishment contingency was to increase the proportion of interpellet intervals without any licks. The drinking of yoked control rats, which received food at the same times as those exposed to the signaled delay contingency (masters), was not consistently reduced. When food-deprivation level was changed to 90%, all master and yoked control rats showed decreases in punished or unpunished schedule-induced drinking. When the body weights were reduced to 70%, most master rats increased punished behavior to levels similar to those of unpunished drinking. This effect was not observed for yoked controls. Therefore, body-weight loss increased the resistance of schedule-induced drinking to reductions by punishment. Food-deprivation effects on punished schedule-induced drinking are similar to their effects on food-maintained lever pressing. This dependency of punishment on food-deprivation level supports the view that schedule-induced drinking can be modified by the same variables that affect operant behavior in general. PMID:7622981

Adaptive control and noise suppression by a variable-gain gradient algorithm

NASA Technical Reports Server (NTRS)

Merhav, S. J.; Mehta, R. S.

1987-01-01

An adaptive control system based on normalized LMS filters is investigated. The finite impulse response of the nonparametric controller is adaptively estimated using a given reference model. Specifically, the following issues are addressed: The stability of the closed loop system is analyzed and heuristically established. Next, the adaptation process is studied for piecewise constant plant parameters. It is shown that by introducing a variable-gain in the gradient algorithm, a substantial reduction in the LMS adaptation rate can be achieved. Finally, process noise at the plant output generally causes a biased estimate of the controller. By introducing a noise suppression scheme, this bias can be substantially reduced and the response of the adapted system becomes very close to that of the reference model. Extensive computer simulations validate these and demonstrate assertions that the system can rapidly adapt to random jumps in plant parameters.

The Gain of Resource Delegation in Distributed Computing Environments

NASA Astrophysics Data System (ADS)

Fölling, Alexander; Grimme, Christian; Lepping, Joachim; Papaspyrou, Alexander

In this paper, we address job scheduling in Distributed Computing Infrastructures, that is a loosely coupled network of autonomous acting High Performance Computing systems. In contrast to the common approach of mutual workload exchange, we consider the more intuitive operator's viewpoint of load-dependent resource reconfiguration. In case of a site's over-utilization, the scheduling system is able to lease resources from other sites to keep up service quality for its local user community. Contrary, the granting of idle resources can increase utilization in times of low local workload and thus ensure higher efficiency. The evaluation considers real workload data and is done with respect to common service quality indicators. For two simple resource exchange policies and three basic setups we show the possible gain of this approach and analyze the dynamics in workload-adaptive reconfiguration behavior.

Prescribed Travel Schedules for Fatigue Management

NASA Technical Reports Server (NTRS)

Whitmire, Alexandra; Johnston, Smith; Lockley, Steven

2011-01-01

The NASA Fatigue Management Team is developing recommendations for managing fatigue during travel and for shift work operations, as Clinical Practice Guidelines for the Management of Circadian Desynchrony in ISS Operations. The Guidelines provide the International Space Station (ISS ) flight surgeons and other operational clinicians with evidence-based recommendations for mitigating fatigue and other factors related to sleep loss and circadian desynchronization. As much international travel is involved both before and after flight, the guidelines provide recommendations for: pre-flight training, in-flight operations, and post-flight rehabilitation. The objective of is to standardize the process by which care is provided to crewmembers, ground controllers, and other support personnel such as trainers, when overseas travel or schedule shifting is required. Proper scheduling of countermeasures - light, darkness, melatonin, diet, exercise, and medications - is the cornerstone for facilitating circadian adaptation, improving sleep, enhancing alertness, and optimizing performance. The Guidelines provide, among other things, prescribed travel schedules that outline the specific implementation of these mitigation strategies. Each travel schedule offers evidence based protocols for properly using the NASA identified countermeasures for fatigue. This presentation will describe the travel implementation schedules and how these can be used to alleviate the effects of jet lag and/or schedule shifts.

Knowledge-Based Scheduling of Arrival Aircraft in the Terminal Area

NASA Technical Reports Server (NTRS)

Krzeczowski, K. J.; Davis, T.; Erzberger, H.; Lev-Ram, Israel; Bergh, Christopher P.

1995-01-01

A knowledge based method for scheduling arrival aircraft in the terminal area has been implemented and tested in real time simulation. The scheduling system automatically sequences, assigns landing times, and assign runways to arrival aircraft by utilizing continuous updates of aircraft radar data and controller inputs. The scheduling algorithm is driven by a knowledge base which was obtained in over two thousand hours of controller-in-the-loop real time simulation. The knowledge base contains a series of hierarchical 'rules' and decision logic that examines both performance criteria, such as delay reductions, as well as workload reduction criteria, such as conflict avoidance. The objective of the algorithm is to devise an efficient plan to land the aircraft in a manner acceptable to the air traffic controllers. This paper describes the scheduling algorithms, gives examples of their use, and presents data regarding their potential benefits to the air traffic system.

Learning Search Control Knowledge for Deep Space Network Scheduling

NASA Technical Reports Server (NTRS)

Gratch, Jonathan; Chien, Steve; DeJong, Gerald

1993-01-01

While the general class of most scheduling problems is NP-hard in worst-case complexity, in practice, for specific distributions of problems and constraints, domain-specific solutions have been shown to perform in much better than exponential time.

A design fix to supervisory control for fault-tolerant scheduling of real-time multiprocessor systems with aperiodic tasks

NASA Astrophysics Data System (ADS)

Devaraj, Rajesh; Sarkar, Arnab; Biswas, Santosh

2015-11-01

In the article 'Supervisory control for fault-tolerant scheduling of real-time multiprocessor systems with aperiodic tasks', Park and Cho presented a systematic way of computing a largest fault-tolerant and schedulable language that provides information on whether the scheduler (i.e., supervisor) should accept or reject a newly arrived aperiodic task. The computation of such a language is mainly dependent on the task execution model presented in their paper. However, the task execution model is unable to capture the situation when the fault of a processor occurs even before the task has arrived. Consequently, a task execution model that does not capture this fact may possibly be assigned for execution on a faulty processor. This problem has been illustrated with an appropriate example. Then, the task execution model of Park and Cho has been modified to strengthen the requirement that none of the tasks are assigned for execution on a faulty processor.

Sliding Mode Control of the X-33 with an Engine Failure

NASA Technical Reports Server (NTRS)

Shtessel, Yuri B.; Hall, Charles E.

2000-01-01

Ascent flight control of the X-3 is performed using two XRS-2200 linear aerospike engines. in addition to aerosurfaces. The baseline control algorithms are PID with gain scheduling. Flight control using an innovative method. Sliding Mode Control. is presented for nominal and engine failed modes of flight. An easy to implement, robust controller. requiring no reconfiguration or gain scheduling is demonstrated through high fidelity flight simulations. The proposed sliding mode controller utilizes a two-loop structure and provides robust. de-coupled tracking of both orientation angle command profiles and angular rate command profiles in the presence of engine failure, bounded external disturbances (wind gusts) and uncertain matrix of inertia. Sliding mode control causes the angular rate and orientation angle tracking error dynamics to be constrained to linear, de-coupled, homogeneous, and vector valued differential equations with desired eigenvalues. Conditions that restrict engine failures to robustness domain of the sliding mode controller are derived. Overall stability of a two-loop flight control system is assessed. Simulation results show that the designed controller provides robust, accurate, de-coupled tracking of the orientation angle command profiles in the presence of external disturbances and vehicle inertia uncertainties, as well as the single engine failed case. The designed robust controller will significantly reduce the time and cost associated with flying new trajectory profiles or orbits, with new payloads, and with modified vehicles

A novel heart rate control model provides insights linking LF-HRV behavior to the open-loop gain.

PubMed

Dvir, Hila; Bobrovsky, Ben Zion; Gabbay, Uri

2013-09-20

Low-frequency heart rate variability (LF-HRV) at rest has already been successfully modeled as self-sustained oscillations in a nonlinear control loop, but these models fail to simulate LF-HRV decreases either during aerobic exercise or in heart failure patients. Following control engineering practices, we assume the existence of a biological excitation (dither) within the heart rate control loop that softens the nonlinearity and studied LF-HRV behavior in a dither-embedded model. We adopted the Ottesen model with some revisions and induced a dither of high-frequency stochastic perturbations. We simulated scenarios of a healthy subject at rest and during aerobic exercise (by decreasing peripheral vascular resistance) and a heart failure patient (by decreasing stroke volume). The simulations resembled physiological LF-HRV behavior, i.e., LF-HRV decreased during aerobic exercise and in the heart failure patient. The simulations exhibited LF-HRV dependency on the open-loop gain, which is related to the product of the feedback gain and the feed forward gain. We are the first to demonstrate that LF-HRV may be dependent on the open-loop gain. Accordingly, reduced open-loop gain results in decreased LF-HRV, and vice versa. Our findings explain a well-known but unexplained observed phenomenon of reduced LF-HRV both in heart failure patients and in healthy subjects performing aerobic exercise. These findings have implications on how changes in LF-HRV can be interpreted physiologically, a necessary step towards the clinical utilization of LF-HRV. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Continuous higher-order sliding mode control with time-varying gain for a class of uncertain nonlinear systems.

PubMed

Han, Yaozhen; Liu, Xiangjie

2016-05-01

This paper presents a continuous higher-order sliding mode (HOSM) control scheme with time-varying gain for a class of uncertain nonlinear systems. The proposed controller is derived from the concept of geometric homogeneity and super-twisting algorithm, and includes two parts, the first part of which achieves smooth finite time stabilization of pure integrator chains. The second part conquers the twice differentiable uncertainty and realizes system robustness by employing super-twisting algorithm. Particularly, time-varying switching control gain is constructed to reduce the switching control action magnitude to the minimum possible value while keeping the property of finite time convergence. Examples concerning the perturbed triple integrator chains and excitation control for single-machine infinite bus power system are simulated respectively to demonstrate the effectiveness and applicability of the proposed approach. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

Scheduler for monitoring objects orbiting earth using satellite-based telescopes

DOEpatents

Olivier, Scot S; Pertica, Alexander J; Riot, Vincent J; De Vries, Willem H; Bauman, Brian J; Nikolaev, Sergei; Henderson, John R; Phillion, Donald W

2015-04-28

An ephemeris refinement system includes satellites with imaging devices in earth orbit to make observations of space-based objects ("target objects") and a ground-based controller that controls the scheduling of the satellites to make the observations of the target objects and refines orbital models of the target objects. The ground-based controller determines when the target objects of interest will be near enough to a satellite for that satellite to collect an image of the target object based on an initial orbital model for the target objects. The ground-based controller directs the schedules to be uploaded to the satellites, and the satellites make observations as scheduled and download the observations to the ground-based controller. The ground-based controller then refines the initial orbital models of the target objects based on the locations of the target objects that are derived from the observations.

Adaptive-gain fast super-twisting sliding mode fault tolerant control for a reusable launch vehicle in reentry phase.

PubMed

Zhang, Yao; Tang, Shengjing; Guo, Jie

2017-11-01

In this paper, a novel adaptive-gain fast super-twisting (AGFST) sliding mode attitude control synthesis is carried out for a reusable launch vehicle subject to actuator faults and unknown disturbances. According to the fast nonsingular terminal sliding mode surface (FNTSMS) and adaptive-gain fast super-twisting algorithm, an adaptive fault tolerant control law for the attitude stabilization is derived to protect against the actuator faults and unknown uncertainties. Firstly, a second-order nonlinear control-oriented model for the RLV is established by feedback linearization method. And on the basis a fast nonsingular terminal sliding mode (FNTSM) manifold is designed, which provides fast finite-time global convergence and avoids singularity problem as well as chattering phenomenon. Based on the merits of the standard super-twisting (ST) algorithm and fast reaching law with adaption, a novel adaptive-gain fast super-twisting (AGFST) algorithm is proposed for the finite-time fault tolerant attitude control problem of the RLV without any knowledge of the bounds of uncertainties and actuator faults. The important feature of the AGFST algorithm includes non-overestimating the values of the control gains and faster convergence speed than the standard ST algorithm. A formal proof of the finite-time stability of the closed-loop system is derived using the Lyapunov function technique. An estimation of the convergence time and accurate expression of convergence region are also provided. Finally, simulations are presented to illustrate the effectiveness and superiority of the proposed control scheme. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Task and Participant Scheduling of Trading Platforms in Vehicular Participatory Sensing Networks

PubMed Central

Shi, Heyuan; Song, Xiaoyu; Gu, Ming; Sun, Jiaguang

2016-01-01

The vehicular participatory sensing network (VPSN) is now becoming more and more prevalent, and additionally has shown its great potential in various applications. A general VPSN consists of many tasks from task, publishers, trading platforms and a crowd of participants. Some literature treats publishers and the trading platform as a whole, which is impractical since they are two independent economic entities with respective purposes. For a trading platform in markets, its purpose is to maximize the profit by selecting tasks and recruiting participants who satisfy the requirements of accepted tasks, rather than to improve the quality of each task. This scheduling problem for a trading platform consists of two parts: which tasks should be selected and which participants to be recruited? In this paper, we investigate the scheduling problem in vehicular participatory sensing with the predictable mobility of each vehicle. A genetic-based trading scheduling algorithm (GTSA) is proposed to solve the scheduling problem. Experiments with a realistic dataset of taxi trajectories demonstrate that GTSA algorithm is efficient for trading platforms to gain considerable profit in VPSN. PMID:27916807

Task and Participant Scheduling of Trading Platforms in Vehicular Participatory Sensing Networks.

PubMed

Shi, Heyuan; Song, Xiaoyu; Gu, Ming; Sun, Jiaguang

2016-11-28

The vehicular participatory sensing network (VPSN) is now becoming more and more prevalent, and additionally has shown its great potential in various applications. A general VPSN consists of many tasks from task, publishers, trading platforms and a crowd of participants. Some literature treats publishers and the trading platform as a whole, which is impractical since they are two independent economic entities with respective purposes. For a trading platform in markets, its purpose is to maximize the profit by selecting tasks and recruiting participants who satisfy the requirements of accepted tasks, rather than to improve the quality of each task. This scheduling problem for a trading platform consists of two parts: which tasks should be selected and which participants to be recruited? In this paper, we investigate the scheduling problem in vehicular participatory sensing with the predictable mobility of each vehicle. A genetic-based trading scheduling algorithm (GTSA) is proposed to solve the scheduling problem. Experiments with a realistic dataset of taxi trajectories demonstrate that GTSA algorithm is efficient for trading platforms to gain considerable profit in VPSN.

A comparison of multiprocessor scheduling methods for iterative data flow architectures

NASA Technical Reports Server (NTRS)

Storch, Matthew

1993-01-01

A comparative study is made between the Algorithm to Architecture Mapping Model (ATAMM) and three other related multiprocessing models from the published literature. The primary focus of all four models is the non-preemptive scheduling of large-grain iterative data flow graphs as required in real-time systems, control applications, signal processing, and pipelined computations. Important characteristics of the models such as injection control, dynamic assignment, multiple node instantiations, static optimum unfolding, range-chart guided scheduling, and mathematical optimization are identified. The models from the literature are compared with the ATAMM for performance, scheduling methods, memory requirements, and complexity of scheduling and design procedures.

Second-generation antipsychotic use in schizophrenia and associated weight gain: a critical review and meta-analysis of behavioral and pharmacologic treatments.

PubMed

Das, Chandan; Mendez, Guillermo; Jagasia, Sonal; Labbate, Lawrence A

2012-08-01

Weight gain in schizophrenia, particularly secondary to second-generation antipsychotic (SGA) use, is a common adverse effect and often is associated with significant physical and psychological morbidity. We performed a critical literature review of all controlled clinical trials for pharmacologic and/or behavioral management of SGA-induced weight gain in schizophrenia patients by searching PubMed and Google Scholar. A meta-analysis was performed to estimate and compare weight changes for various medications and behavioral interventions. Sample sizes generally were small. Clinical trials were 6 weeks to 1 year, and weight loss was modest with any treatment. Although several adjunctive pharmacologic treatments showed no weight loss, sibutramine, metformin, and topiramate showed some benefit. Amantadine and orlistat were somewhat less effective and had lower rates of tolerability. Among the behavioral therapies, nutritional counseling combined with exercise showed the most benefit. Behavioral therapies, although modest, showed the most consistent benefits compared with controls. Scheduled pharmacologic treatment to prevent weight gain or promote weight loss in schizophrenia patients on SGA therapy is limited based on current studies. Switching antipsychotic agents has not been established as a long-term solution. Additional long-term studies are required to influence clinical practice.

Space communications scheduler: A rule-based approach to adaptive deadline scheduling

NASA Technical Reports Server (NTRS)

Straguzzi, Nicholas

1990-01-01

Job scheduling is a deceptively complex subfield of computer science. The highly combinatorial nature of the problem, which is NP-complete in nearly all cases, requires a scheduling program to intelligently transverse an immense search tree to create the best possible schedule in a minimal amount of time. In addition, the program must continually make adjustments to the initial schedule when faced with last-minute user requests, cancellations, unexpected device failures, quests, cancellations, unexpected device failures, etc. A good scheduler must be quick, flexible, and efficient, even at the expense of generating slightly less-than-optimal schedules. The Space Communication Scheduler (SCS) is an intelligent rule-based scheduling system. SCS is an adaptive deadline scheduler which allocates modular communications resources to meet an ordered set of user-specified job requests on board the NASA Space Station. SCS uses pattern matching techniques to detect potential conflicts through algorithmic and heuristic means. As a result, the system generates and maintains high density schedules without relying heavily on backtracking or blind search techniques. SCS is suitable for many common real-world applications.

Attentional Gain Control of Ongoing Cortical Speech Representations in a “Cocktail Party”

PubMed Central

Kerlin, Jess R.; Shahin, Antoine J.; Miller, Lee M.

2010-01-01

Normal listeners possess the remarkable perceptual ability to select a single speech stream among many competing talkers. However, few studies of selective attention have addressed the unique nature of speech as a temporally extended and complex auditory object. We hypothesized that sustained selective attention to speech in a multi-talker environment would act as gain control on the early auditory cortical representations of speech. Using high-density electroencephalography and a template-matching analysis method, we found selective gain to the continuous speech content of an attended talker, greatest at a frequency of 4–8 Hz, in auditory cortex. In addition, the difference in alpha power (8–12 Hz) at parietal sites across hemispheres indicated the direction of auditory attention to speech, as has been previously found in visual tasks. The strength of this hemispheric alpha lateralization, in turn, predicted an individual’s attentional gain of the cortical speech signal. These results support a model of spatial speech stream segregation, mediated by a supramodal attention mechanism, enabling selection of the attended representation in auditory cortex. PMID:20071526

Characterization of Tactical Departure Scheduling in the National Airspace System

NASA Technical Reports Server (NTRS)

Capps, Alan; Engelland, Shawn A.

2011-01-01

This paper discusses and analyzes current day utilization and performance of the tactical departure scheduling process in the National Airspace System (NAS) to understand the benefits in improving this process. The analysis used operational air traffic data from over 1,082,000 flights during the month of January, 2011. Specific metrics included the frequency of tactical departure scheduling, site specific variances in the technology's utilization, departure time prediction compliance used in the tactical scheduling process and the performance with which the current system can predict the airborne slot that aircraft are being scheduled into from the airport surface. Operational data analysis described in this paper indicates significant room for improvement exists in the current system primarily in the area of reduced departure time prediction uncertainty. Results indicate that a significant number of tactically scheduled aircraft did not meet their scheduled departure slot due to departure time uncertainty. In addition to missed slots, the operational data analysis identified increased controller workload associated with tactical departures which were subject to traffic management manual re-scheduling or controller swaps. An analysis of achievable levels of departure time prediction accuracy as obtained by a new integrated surface and tactical scheduling tool is provided to assess the benefit it may provide as a solution to the identified shortfalls. A list of NAS facilities which are likely to receive the greatest benefit from the integrated surface and tactical scheduling technology are provided.

Peer-to-peer Cooperative Scheduling Architecture for National Grid Infrastructure

NASA Astrophysics Data System (ADS)

Matyska, Ludek; Ruda, Miroslav; Toth, Simon

For some ten years, the Czech National Grid Infrastructure MetaCentrum uses a single central PBSPro installation to schedule jobs across the country. This centralized approach keeps a full track about all the clusters, providing support for jobs spanning several sites, implementation for the fair-share policy and better overall control of the grid environment. Despite a steady progress in the increased stability and resilience to intermittent very short network failures, growing number of sites and processors makes this architecture, with a single point of failure and scalability limits, obsolete. As a result, a new scheduling architecture is proposed, which relies on higher autonomy of clusters. It is based on a peer to peer network of semi-independent schedulers for each site or even cluster. Each scheduler accepts jobs for the whole infrastructure, cooperating with other schedulers on implementation of global policies like central job accounting, fair-share, or submission of jobs across several sites. The scheduling system is integrated with the Magrathea system to support scheduling of virtual clusters, including the setup of their internal network, again eventually spanning several sites. On the other hand, each scheduler is local to one of several clusters and is able to directly control and submit jobs to them even if the connection of other scheduling peers is lost. In parallel to the change of the overall architecture, the scheduling system itself is being replaced. Instead of PBSPro, chosen originally for its declared support of large scale distributed environment, the new scheduling architecture is based on the open-source Torque system. The implementation and support for the most desired properties in PBSPro and Torque are discussed and the necessary modifications to Torque to support the MetaCentrum scheduling architecture are presented, too.

A microeconomic scheduler for parallel computers

NASA Technical Reports Server (NTRS)

Stoica, Ion; Abdel-Wahab, Hussein; Pothen, Alex

1995-01-01

We describe a scheduler based on the microeconomic paradigm for scheduling on-line a set of parallel jobs in a multiprocessor system. In addition to the classical objectives of increasing the system throughput and reducing the response time, we consider fairness in allocating system resources among the users, and providing the user with control over the relative performances of his jobs. We associate with every user a savings account in which he receives money at a constant rate. When a user wants to run a job, he creates an expense account for that job to which he transfers money from his savings account. The job uses the funds in its expense account to obtain the system resources it needs for execution. The share of the system resources allocated to the user is directly related to the rate at which the user receives money; the rate at which the user transfers money into a job expense account controls the job's performance. We prove that starvation is not possible in our model. Simulation results show that our scheduler improves both system and user performances in comparison with two different variable partitioning policies. It is also shown to be effective in guaranteeing fairness and providing control over the performance of jobs.

Scheduling Results for the THEMIS Observation Scheduling Tool

NASA Technical Reports Server (NTRS)

Mclaren, David; Rabideau, Gregg; Chien, Steve; Knight, Russell; Anwar, Sadaat; Mehall, Greg; Christensen, Philip

2011-01-01

We describe a scheduling system intended to assist in the development of instrument data acquisitions for the THEMIS instrument, onboard the Mars Odyssey spacecraft, and compare results from multiple scheduling algorithms. This tool creates observations of both (a) targeted geographical regions of interest and (b) general mapping observations, while respecting spacecraft constraints such as data volume, observation timing, visibility, lighting, season, and science priorities. This tool therefore must address both geometric and state/timing/resource constraints. We describe a tool that maps geometric polygon overlap constraints to set covering constraints using a grid-based approach. These set covering constraints are then incorporated into a greedy optimization scheduling algorithm incorporating operations constraints to generate feasible schedules. The resultant tool generates schedules of hundreds of observations per week out of potential thousands of observations. This tool is currently under evaluation by the THEMIS observation planning team at Arizona State University.

GD SDR Automatic Gain Control Characterization Testing

NASA Technical Reports Server (NTRS)

Nappier, Jennifer M.; Briones, Janette C.

2013-01-01

The General Dynamics (GD) S-Band software defined radio (SDR) in the Space Communications and Navigation (SCAN) Testbed on the International Space Station (ISS) will provide experimenters an opportunity to develop and demonstrate experimental waveforms in space. The GD SDR platform and initial waveform were characterized on the ground before launch and the data will be compared to the data that will be collected during on-orbit operations. A desired function of the SDR is to estimate the received signal to noise ratio (SNR), which would enable experimenters to better determine on-orbit link conditions. The GD SDR does not have an SNR estimator, but it does have an analog and a digital automatic gain control (AGC). The AGCs can be used to estimate the SDR input power which can be converted into a SNR. Tests were conducted to characterize the AGC response to changes in SDR input power and temperature. This purpose of this paper is to describe the tests that were conducted, discuss the results showi ng how the AGCs relate to the SDR input power, and provide recommendations for AGC testing and characterization.

GD SDR Automatic Gain Control Characterization Testing

NASA Technical Reports Server (NTRS)

Nappier, Jennifer M.; Briones, Janette C.

2013-01-01

The General Dynamics (GD) S-Band software defined radio (SDR) in the Space Communications and Navigation (SCAN) Testbed on the International Space Station (ISS) will provide experimenters an opportunity to develop and demonstrate experimental waveforms in space. The GD SDR platform and initial waveform were characterized on the ground before launch and the data will be compared to the data that will be collected during on-orbit operations. A desired function of the SDR is to estimate the received signal to noise ratio (SNR), which would enable experimenters to better determine on-orbit link conditions. The GD SDR does not have an SNR estimator, but it does have an analog and a digital automatic gain control (AGC). The AGCs can be used to estimate the SDR input power which can be converted into a SNR. Tests were conducted to characterize the AGC response to changes in SDR input power and temperature. This purpose of this paper is to describe the tests that were conducted, discuss the results showing how the AGCs relate to the SDR input power, and provide recommendations for AGC testing and characterization.

Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling.

PubMed

Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

2015-09-18

This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols.

Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling

PubMed Central

Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

2015-01-01

This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols. PMID:26393608

Adaptive Control for Uncertain Nonlinear Multi-Input Multi-Output Systems

NASA Technical Reports Server (NTRS)

Cao, Chengyu (Inventor); Hovakimyan, Naira (Inventor); Xargay, Enric (Inventor)

2014-01-01

Systems and methods of adaptive control for uncertain nonlinear multi-input multi-output systems in the presence of significant unmatched uncertainty with assured performance are provided. The need for gain-scheduling is eliminated through the use of bandwidth-limited (low-pass) filtering in the control channel, which appropriately attenuates the high frequencies typically appearing in fast adaptation situations and preserves the robustness margins in the presence of fast adaptation.

Weight gain in preterm infants following parent-administered Vimala massage: a randomized controlled trial.

PubMed

Gonzalez, Alma Patricia; Vasquez-Mendoza, Guadalupe; García-Vela, Alfonso; Guzmán-Ramirez, Andres; Salazar-Torres, Marcos; Romero-Gutierrez, Gustavo

2009-04-01

Massage has been proposed as a way of facilitating development and growth of newborns through its effects on increasing blood flow, heart rate, digestion, and immunity. Massage might increase basal metabolism and nutrient absorption through endocrine effects such as increase in insulin and adrenaline and decrease in cortisol. Preliminary studies have suggested significant impact on weight gain with shortening of in-hospital stays of up to 6 days. We compared weight gain among preterm infants receiving Vimala massage plus usual care versus usual care alone. A randomized controlled trial was conducted. Sixty clinically stable preterm newborns with a corrected gestational age of 30 to 35 weeks receiving enteral nutrition in the hospital nursery were included. Half of them were assigned at random to receive Vimala massage twice daily for 10 days plus usual nursery care; the others received usual nursery care. Weight, head circumference, caloric intake, and nutritional method were recorded daily. Group characteristics were compared with analysis of variance, T test, and chi (2) test as appropriate. There were no differences between groups in gender, gestational age, initial weight, head circumference, and caloric intake and type of nutrition at baseline. Infants receiving massage had a larger weight gain versus the control group since the third day (188.2 +/- 41.20 g/kg versus 146.7 +/- 56.43 g/kg, P < 0.001). Hospital stay was shorter in infants receiving massage and usual nursery care (15.63 +/- 5.41 days versus 19.33 +/- 7.92 days, P = 0.03). The addition of parent-administered Vimala massage to usual nursery care resulted in increased weight gain and shorter hospital stay among clinically stable preterm newborns.

The inhibitory microcircuit of the substantia nigra provides feedback gain control of the basal ganglia output

PubMed Central

Brown, Jennifer; Pan, Wei-Xing; Dudman, Joshua Tate

2014-01-01

Dysfunction of the basal ganglia produces severe deficits in the timing, initiation, and vigor of movement. These diverse impairments suggest a control system gone awry. In engineered systems, feedback is critical for control. By contrast, models of the basal ganglia highlight feedforward circuitry and ignore intrinsic feedback circuits. In this study, we show that feedback via axon collaterals of substantia nigra projection neurons control the gain of the basal ganglia output. Through a combination of physiology, optogenetics, anatomy, and circuit mapping, we elaborate a general circuit mechanism for gain control in a microcircuit lacking interneurons. Our data suggest that diverse tonic firing rates, weak unitary connections and a spatially diffuse collateral circuit with distinct topography and kinetics from feedforward input is sufficient to implement divisive feedback inhibition. The importance of feedback for engineered systems implies that the intranigral microcircuit, despite its absence from canonical models, could be essential to basal ganglia function. DOI: http://dx.doi.org/10.7554/eLife.02397.001 PMID:24849626

Scheduling techniques in the Request Oriented Scheduling Engine (ROSE)

NASA Technical Reports Server (NTRS)

Zoch, David R.

1991-01-01

Scheduling techniques in the ROSE are presented in the form of the viewgraphs. The following subject areas are covered: agenda; ROSE summary and history; NCC-ROSE task goals; accomplishments; ROSE timeline manager; scheduling concerns; current and ROSE approaches; initial scheduling; BFSSE overview and example; and summary.

Interference Cognizant Network Scheduling

NASA Technical Reports Server (NTRS)

Hall, Brendan (Inventor); Bonk, Ted (Inventor); DeLay, Benjamin F. (Inventor); Varadarajan, Srivatsan (Inventor); Smithgall, William Todd (Inventor)

2017-01-01

Systems and methods for interference cognizant network scheduling are provided. In certain embodiments, a method of scheduling communications in a network comprises identifying a bin of a global timeline for scheduling an unscheduled virtual link, wherein a bin is a segment of the timeline; identifying a pre-scheduled virtual link in the bin; and determining if the pre-scheduled and unscheduled virtual links share a port. In certain embodiments, if the unscheduled and pre-scheduled virtual links don't share a port, scheduling transmission of the unscheduled virtual link to overlap with the scheduled transmission of the pre-scheduled virtual link; and if the unscheduled and pre-scheduled virtual links share a port: determining a start time delay for the unscheduled virtual link based on the port; and scheduling transmission of the unscheduled virtual link in the bin based on the start time delay to overlap part of the scheduled transmission of the pre-scheduled virtual link.

CHMICA and MDMB-FUBINACA) Into Schedule I. Notice of Intent.

PubMed

2016-12-21

The Administrator of the Drug Enforcement Administration is issuing this notice of intent to temporarily schedule six synthetic cannabinoids: methyl 2-(1-(5-fluoropentyl)-1H-indazole-3-carboxamido)-3,3-dimethylbutanoate [5F-ADB; 5F-MDMB-PINACA]; methyl 2-(1-(5-fluoropentyl)-1H-indazole-3-carboxamido)-3-methylbutanoate [5F-AMB]; N-(adamantan-1-yl)-1-(5-fluoropentyl)-1H-indazole-3-carboxamide [5F-APINACA, 5F-AKB48]; N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)-1-(4-fluorobenzyl)-1H-indazole-3-carboxamide [ADB-FUBINACA]; methyl 2-(1-(cyclohexylmethyl)-1H-indole-3-carboxamido)-3,3-dimethylbutanoate [MDMB-CHMICA, MMB-CHMINACA] and methyl 2-(1-(4-fluorobenzyl)-1H-indazole-3-carboxamido)-3,3-dimethylbutanoate [MDMB-FUBINACA], into schedule I pursuant to the temporary scheduling provisions of the Controlled Substances Act (CSA). This action is based on a finding by the Administrator that the placement of these synthetic cannabinoids into schedule I of the Controlled Substances Act is necessary to avoid an imminent hazard to the public safety. Any final order will impose the administrative, civil, and criminal sanctions and regulatory controls applicable to schedule I substances under the Controlled Substances Act on the manufacture, distribution, possession, importation, exportation of, and research and conduct with, instructional activities of these synthetic cannabinoids.

Olfactory receptor neurons use gain control and complementary kinetics to encode intermittent odorant stimuli

PubMed Central

Gorur-Shandilya, Srinivas; Demir, Mahmut; Long, Junjiajia; Clark, Damon A; Emonet, Thierry

2017-01-01

Insects find food and mates by navigating odorant plumes that can be highly intermittent, with intensities and durations that vary rapidly over orders of magnitude. Much is known about olfactory responses to pulses and steps, but it remains unclear how olfactory receptor neurons (ORNs) detect the intensity and timing of natural stimuli, where the absence of scale in the signal makes detection a formidable olfactory task. By stimulating Drosophila ORNs in vivo with naturalistic and Gaussian stimuli, we show that ORNs adapt to stimulus mean and variance, and that adaptation and saturation contribute to naturalistic sensing. Mean-dependent gain control followed the Weber-Fechner relation and occurred primarily at odor transduction, while variance-dependent gain control occurred at both transduction and spiking. Transduction and spike generation possessed complementary kinetic properties, that together preserved the timing of odorant encounters in ORN spiking, regardless of intensity. Such scale-invariance could be critical during odor plume navigation. DOI: http://dx.doi.org/10.7554/eLife.27670.001 PMID:28653907

DSN Scheduling Engine

NASA Technical Reports Server (NTRS)

Clement, Bradley; Johnston, Mark; Wax, Allan; Chouinard, Caroline

2008-01-01

The DSN (Deep Space Network) Scheduling Engine targets all space missions that use DSN services. It allows clients to issue scheduling, conflict identification, conflict resolution, and status requests in XML over a Java Message Service interface. The scheduling requests may include new requirements that represent a set of tracks to be scheduled under some constraints. This program uses a heuristic local search to schedule a variety of schedule requirements, and is being infused into the Service Scheduling Assembly, a mixed-initiative scheduling application. The engine resolves conflicting schedules of resource allocation according to a range of existing and possible requirement specifications, including optional antennas; start of track and track duration ranges; periodic tracks; locks on track start, duration, and allocated antenna; MSPA (multiple spacecraft per aperture); arraying/VLBI (very long baseline interferometry)/delta DOR (differential one-way ranging); continuous tracks; segmented tracks; gap-to-track ratio; and override or block-out of requirements. The scheduling models now include conflict identification for SOA(start of activity), BOT (beginning of track), RFI (radio frequency interference), and equipment constraints. This software will search through all possible allocations while providing a best-effort solution at any time. The engine reschedules to accommodate individual emergency tracks in 0.2 second, and emergency antenna downtime in 0.2 second. The software handles doubling of one mission's track requests over one week (to 42 total) in 2.7 seconds. Further tests will be performed in the context of actual schedules.

On optimal scheduling and air traffic control in the near terminal area. M.S. Thesis

NASA Technical Reports Server (NTRS)

Sarris, A. H.

1971-01-01

A scheme is proposed for automated air traffic control of landing aircraft in the vicinity of the airport. Each aircraft is put under the control of an airport-based computer as soon as it enters the near-terminal area (NTA). Scheduling is done immediately thereafter. The aircraft is given a flight plan which, if followed precisely, will lead it to the runway at a prespecified time. The geometry of the airspace in the NTA is chosen so that delays are executed far from the outer marker, and violations of minimum altitude and lateral separations are avoided. Finally, a solution to the velocity mix problem is proposed.

Power Grid Maintenance Scheduling Intelligence Arrangement Supporting System Based on Power Flow Forecasting

NASA Astrophysics Data System (ADS)

Xie, Chang; Wen, Jing; Liu, Wenying; Wang, Jiaming

With the development of intelligent dispatching, the intelligence level of network control center full-service urgent need to raise. As an important daily work of network control center, the application of maintenance scheduling intelligent arrangement to achieve high-quality and safety operation of power grid is very important. By analyzing the shortages of the traditional maintenance scheduling software, this paper designs a power grid maintenance scheduling intelligence arrangement supporting system based on power flow forecasting, which uses the advanced technologies in maintenance scheduling, such as artificial intelligence, online security checking, intelligent visualization techniques. It implements the online security checking of maintenance scheduling based on power flow forecasting and power flow adjusting based on visualization, in order to make the maintenance scheduling arrangement moreintelligent and visual.

Analysis of sequencing and scheduling methods for arrival traffic

NASA Technical Reports Server (NTRS)

Neuman, Frank; Erzberger, Heinz

1990-01-01

The air traffic control subsystem that performs scheduling is discussed. The function of the scheduling algorithms is to plan automatically the most efficient landing order and to assign optimally spaced landing times to all arrivals. Several important scheduling algorithms are described and the statistical performance of the scheduling algorithms is examined. Scheduling brings order to an arrival sequence for aircraft. First-come-first-served scheduling (FCFS) establishes a fair order, based on estimated times of arrival, and determines proper separations. Because of the randomness of the traffic, gaps will remain in the scheduled sequence of aircraft. These gaps are filled, or partially filled, by time-advancing the leading aircraft after a gap while still preserving the FCFS order. Tightly scheduled groups of aircraft remain with a mix of heavy and large aircraft. Separation requirements differ for different types of aircraft trailing each other. Advantage is taken of this fact through mild reordering of the traffic, thus shortening the groups and reducing average delays. Actual delays for different samples with the same statistical parameters vary widely, especially for heavy traffic.

Flight of frigatebirds inside clouds - energy gain, stability and control.

PubMed

Sachs, Gottfried; Weimerskirch, Henri

2018-07-07

Investigating the unique ability of frigatebirds of flying inside clouds, it is shown that they achieve a large energy gain by ascents to high altitudes in strong updrafts of trade cumulus clouds. Frigatebirds often perform that kind of flight, at daytime as well as in the night. This suggests that they are capable of flying inside clouds in a controlled and stabilized manner. The control requirements for ascents in terms of a circling flight in updrafts of trade cumulus clouds are analyzed, and the necessary aerodynamic control moments are determined. Based on a stability investigation, it is shown that there are restoring effects which act against disturbances causing possible deviations from the circling flight condition. The aerodynamic moments which effectuate that stabilization are identified. Furthermore, the problem of neutral azimuth stability which generally exists in the flight of birds and which is the reason for continually increasing deviations from the course is dealt with. It is shown for the circling flight mode of frigatebirds inside clouds that, here, deviations are small and remain constant, suggesting that a corrective control action is not required. This is particularly important for circling flight in conditions without a visual reference, like inside clouds. Copyright © 2018 Elsevier Ltd. All rights reserved.

Toward an Autonomous Telescope Network: the TBT Scheduler

NASA Astrophysics Data System (ADS)

Racero, E.; Ibarra, A.; Ocaña, F.; de Lis, S. B.; Ponz, J. D.; Castillo, M.; Sánchez-Portal, M.

2015-09-01

Within the ESA SSA program, it is foreseen to deploy several robotic telescopes to provide surveillance and tracking services for hazardous objects. The TBT project will procure a validation platform for an autonomous optical observing system in a realistic scenario, consisting of two telescopes located in Spain and Australia, to collect representative test data for precursor SSA services. In this context, the planning and scheduling of the night consists of two software modules, the TBT Scheduler, that will allow the manual and autonomous planning of the night, and the control of the real-time response of the system, done by the RTS2 internal scheduler. The TBT Scheduler allocates tasks for both telescopes without human intervention. Every night it takes all the inputs needed and prepares the schedule following some predefined rules. The main purpose of the scheduler is the distribution of the time for follow-up of recently discovered targets and surveys. The TBT Scheduler considers the overall performance of the system, and combine follow-up with a priori survey strategies for both kind of objects. The strategy is defined according to the expected combined performance for both systems the upcoming night (weather, sky brightness, object accessibility and priority). Therefore, TBT Scheduler defines the global approach for the network and relies on the RTS2 internal scheduler for the final detailed distribution of tasks at each sensor.

An approach to multivariable control of manipulators

NASA Technical Reports Server (NTRS)

Seraji, H.

1987-01-01

The paper presents simple schemes for multivariable control of multiple-joint robot manipulators in joint and Cartesian coordinates. The joint control scheme consists of two independent multivariable feedforward and feedback controllers. The feedforward controller is the minimal inverse of the linearized model of robot dynamics and contains only proportional-double-derivative (PD2) terms - implying feedforward from the desired position, velocity and acceleration. This controller ensures that the manipulator joint angles track any reference trajectories. The feedback controller is of proportional-integral-derivative (PID) type and is designed to achieve pole placement. This controller reduces any initial tracking error to zero as desired and also ensures that robust steady-state tracking of step-plus-exponential trajectories is achieved by the joint angles. Simple and explicit expressions of computation of the feedforward and feedback gains are obtained based on the linearized model of robot dynamics. This leads to computationally efficient schemes for either on-line gain computation or off-line gain scheduling to account for variations in the linearized robot model due to changes in the operating point. The joint control scheme is extended to direct control of the end-effector motion in Cartesian space. Simulation results are given for illustration.

Mission Operations Planning and Scheduling System (MOPSS)

NASA Technical Reports Server (NTRS)

Wood, Terri; Hempel, Paul

2011-01-01

MOPSS is a generic framework that can be configured on the fly to support a wide range of planning and scheduling applications. It is currently used to support seven missions at Goddard Space Flight Center (GSFC) in roles that include science planning, mission planning, and real-time control. Prior to MOPSS, each spacecraft project built its own planning and scheduling capability to plan satellite activities and communications and to create the commands to be uplinked to the spacecraft. This approach required creating a data repository for storing planning and scheduling information, building user interfaces to display data, generating needed scheduling algorithms, and implementing customized external interfaces. Complex scheduling problems that involved reacting to multiple variable situations were analyzed manually. Operators then used the results to add commands to the schedule. Each architecture was unique to specific satellite requirements. MOPSS is an expert system that automates mission operations and frees the flight operations team to concentrate on critical activities. It is easily reconfigured by the flight operations team as the mission evolves. The heart of the system is a custom object-oriented data layer mapped onto an Oracle relational database. The combination of these two technologies allows a user or system engineer to capture any type of scheduling or planning data in the system's generic data storage via a GUI.

Initial Investigations of Controller Tools and Procedures for Schedule-Based Arrival Operations with Mixed Flight-Deck Interval Management Equipage

NASA Technical Reports Server (NTRS)

Callantine, Todd J.; Cabrall, Christopher; Kupfer, Michael; Omar, Faisal G.; Prevot, Thomas

2012-01-01

NASA?s Air Traffic Management Demonstration-1 (ATD-1) is a multi-year effort to demonstrate high-throughput, fuel-efficient arrivals at a major U.S. airport using NASA-developed scheduling automation, controller decision-support tools, and ADS-B-enabled Flight-Deck Interval Management (FIM) avionics. First-year accomplishments include the development of a concept of operations for managing scheduled arrivals flying Optimized Profile Descents with equipped aircraft conducting FIM operations, and the integration of laboratory prototypes of the core ATD-1 technologies. Following each integration phase, a human-in-the-loop simulation was conducted to evaluate and refine controller tools, procedures, and clearance phraseology. From a ground-side perspective, the results indicate the concept is viable and the operations are safe and acceptable. Additional training is required for smooth operations that yield notable benefits, particularly in the areas of FIM operations and clearance phraseology.

Modeling and Control of a Fixed Wing Tilt-Rotor Tri-Copter

NASA Astrophysics Data System (ADS)

Summers, Alexander

The following thesis considers modeling and control of a fixed wing tilt-rotor tri-copter. An emphasis of the conceptual design is made toward payload transport. Aerodynamic panel code and CAD design provide the base aerodynamic, geometric, mass, and inertia properties. A set of non-linear dynamics are created considering gravity, aerodynamics in vertical takeoff and landing (VTOL) and forward flight, and propulsion applied to a three degree of freedom system. A transition strategy, that removes trajectory planning by means of scheduled inputs, is theorized. Three discrete controllers, utilizing separate control techniques, are applied to ensure stability in the aerodynamic regions of VTOL, transition, and forward flight. The controller techniques include linear quadratic regulation, full state integral action, gain scheduling, and proportional integral derivative (PID) flight control. Simulation of the model control system for flight from forward to backward transition is completed with mass and center of gravity variation.

Artificial intelligence for the CTA Observatory scheduler

NASA Astrophysics Data System (ADS)

Colomé, Josep; Colomer, Pau; Campreciós, Jordi; Coiffard, Thierry; de Oña, Emma; Pedaletti, Giovanna; Torres, Diego F.; Garcia-Piquer, Alvaro

2014-08-01

The Cherenkov Telescope Array (CTA) project will be the next generation ground-based very high energy gamma-ray instrument. The success of the precursor projects (i.e., HESS, MAGIC, VERITAS) motivated the construction of this large infrastructure that is included in the roadmap of the ESFRI projects since 2008. CTA is planned to start the construction phase in 2015 and will consist of two arrays of Cherenkov telescopes operated as a proposal-driven open observatory. Two sites are foreseen at the southern and northern hemispheres. The CTA observatory will handle several observation modes and will have to operate tens of telescopes with a highly efficient and reliable control. Thus, the CTA planning tool is a key element in the control layer for the optimization of the observatory time. The main purpose of the scheduler for CTA is the allocation of multiple tasks to one single array or to multiple sub-arrays of telescopes, while maximizing the scientific return of the facility and minimizing the operational costs. The scheduler considers long- and short-term varying conditions to optimize the prioritization of tasks. A short-term scheduler provides the system with the capability to adapt, in almost real-time, the selected task to the varying execution constraints (i.e., Targets of Opportunity, health or status of the system components, environment conditions). The scheduling procedure ensures that long-term planning decisions are correctly transferred to the short-term prioritization process for a suitable selection of the next task to execute on the array. In this contribution we present the constraints to CTA task scheduling that helped classifying it as a Flexible Job-Shop Problem case and finding its optimal solution based on Artificial Intelligence techniques. We describe the scheduler prototype that uses a Guarded Discrete Stochastic Neural Network (GDSN), for an easy representation of the possible long- and short-term planning solutions, and Constraint

Design Principles and Algorithms for Air Traffic Arrival Scheduling

NASA Technical Reports Server (NTRS)

Erzberger, Heinz; Itoh, Eri

2014-01-01

This report presents design principles and algorithms for building a real-time scheduler of arrival aircraft based on a first-come-first-served (FCFS) scheduling protocol. The algorithms provide the conceptual and computational foundation for the Traffic Management Advisor (TMA) of the Center/terminal radar approach control facilities (TRACON) automation system, which comprises a set of decision support tools for managing arrival traffic at major airports in the United States. The primary objective of the scheduler is to assign arrival aircraft to a favorable landing runway and schedule them to land at times that minimize delays. A further objective of the scheduler is to allocate delays between high-altitude airspace far away from the airport and low-altitude airspace near the airport. A method of delay allocation is described that minimizes the average operating cost in the presence of errors in controlling aircraft to a specified landing time. This report is a revision of an earlier paper first presented as part of an Advisory Group for Aerospace Research and Development (AGARD) lecture series in September 1995. The authors, during vigorous discussions over the details of this paper, felt it was important to the air-trafficmanagement (ATM) community to revise and extend the original 1995 paper, providing more detail and clarity and thereby allowing future researchers to understand this foundational work as the basis for the TMA's scheduling algorithms.

NASA scheduling technologies

NASA Technical Reports Server (NTRS)

Adair, Jerry R.

1994-01-01

This paper is a consolidated report on ten major planning and scheduling systems that have been developed by the National Aeronautics and Space Administration (NASA). A description of each system, its components, and how it could be potentially used in private industry is provided in this paper. The planning and scheduling technology represented by the systems ranges from activity based scheduling employing artificial intelligence (AI) techniques to constraint based, iterative repair scheduling. The space related application domains in which the systems have been deployed vary from Space Shuttle monitoring during launch countdown to long term Hubble Space Telescope (HST) scheduling. This paper also describes any correlation that may exist between the work done on different planning and scheduling systems. Finally, this paper documents the lessons learned from the work and research performed in planning and scheduling technology and describes the areas where future work will be conducted.

The GBT Dynamic Scheduling System: A New Scheduling Paradigm

NASA Astrophysics Data System (ADS)

O'Neil, K.; Balser, D.; Bignell, C.; Clark, M.; Condon, J.; McCarty, M.; Marganian, P.; Shelton, A.; Braatz, J.; Harnett, J.; Maddalena, R.; Mello, M.; Sessoms, E.

2009-09-01

The Robert C. Byrd Green Bank Telescope (GBT) is implementing a new Dynamic Scheduling System (DSS) designed to maximize the observing efficiency of the telescope while ensuring that none of the flexibility and ease of use of the GBT is harmed and that the data quality of observations is not adversely affected. To accomplish this, the GBT DSS is implementing a dynamic scheduling system which schedules observers, rather than running scripts. The DSS works by breaking each project into one or more sessions which have associated observing criteria such as RA, Dec, and frequency. Potential observers may also enter dates when members of their team will not be available for either on-site or remote observing. The scheduling algorithm uses those data, along with the predicted weather, to determine the most efficient schedule for the GBT. The DSS provides all observers at least 24 hours notice of their upcoming observing. In the uncommon (< 20%) case where the actual weather does not match the predictions, a backup project, chosen from the database, is run instead. Here we give an overview of the GBT DSS project, including the ranking and scheduling algorithms for the sessions, the scheduling probabilities generation, the web framework for the system, and an overview of the results from the beta testing which were held from June - September, 2008.

Considerations for Using an Incremental Scheduler for Human Exploration Task Scheduling

NASA Technical Reports Server (NTRS)

Jaap, John; Phillips, Shaun

2005-01-01

As humankind embarks on longer space missions farther from home, the requirements and environments for scheduling the activities performed on these missions are changing. As we begin to prepare for these missions it is appropriate to evaluate the merits and applicability of the different types of scheduling engines. Scheduling engines temporally arrange tasks onto a timeline so that all constraints and objectives are met and resources are not overbooked. Scheduling engines used to schedule space missions fall into three general categories: batch, mixed-initiative, and incremental. This paper presents an assessment of the engine types, a discussion of the impact of human exploration of the moon and Mars on planning and scheduling, and the applicability of the different types of scheduling engines. This paper will pursue the hypothesis that incremental scheduling engines may have a place in the new environment; they have the potential to reduce cost, to improve the satisfaction of those who execute or benefit from a particular timeline (the customers), and to allow astronauts to plan their own tasks.

Schedule Risk Assessment

NASA Technical Reports Server (NTRS)

Smith, Greg

2003-01-01

Schedule risk assessments determine the likelihood of finishing on time. Each task in a schedule has a varying degree of probability of being finished on time. A schedule risk assessment quantifies these probabilities by assigning values to each task. This viewgraph presentation contains a flow chart for conducting a schedule risk assessment, and profiles applicable several methods of data analysis.

Alternative Work Schedules Increase Employee Satisfaction.

ERIC Educational Resources Information Center

Turney, John R.; Cohen, Stanley L.

1983-01-01

Facets of alternative work schedules (AWS) are discussed: importance of employee control, possible negative consequences, AWS handbook, time monitoring systems, and treatment of exceptions. AWS' effect on productivity and motivation is examined. (SK)

The inhibitory microcircuit of the substantia nigra provides feedback gain control of the basal ganglia output.

PubMed

Brown, Jennifer; Pan, Wei-Xing; Dudman, Joshua Tate

2014-05-21

Dysfunction of the basal ganglia produces severe deficits in the timing, initiation, and vigor of movement. These diverse impairments suggest a control system gone awry. In engineered systems, feedback is critical for control. By contrast, models of the basal ganglia highlight feedforward circuitry and ignore intrinsic feedback circuits. In this study, we show that feedback via axon collaterals of substantia nigra projection neurons control the gain of the basal ganglia output. Through a combination of physiology, optogenetics, anatomy, and circuit mapping, we elaborate a general circuit mechanism for gain control in a microcircuit lacking interneurons. Our data suggest that diverse tonic firing rates, weak unitary connections and a spatially diffuse collateral circuit with distinct topography and kinetics from feedforward input is sufficient to implement divisive feedback inhibition. The importance of feedback for engineered systems implies that the intranigral microcircuit, despite its absence from canonical models, could be essential to basal ganglia function. DOI: http://dx.doi.org/10.7554/eLife.02397.001. Copyright © 2014, Brown et al.

Contribution of Schedule Delays to Cost Growth: How to Make Peace with a Marching Army

NASA Technical Reports Server (NTRS)

Majerowicz, Walt; Bitten, Robert; Emmons, Debra; Shinn, Stephen A.

2016-01-01

Numerous research papers have shown that cost and schedule growth are interrelated for NASA space science missions. Although there has shown to be a strong correlation of cost growth with schedule growth, it is unclear what percentage of cost growth is caused by schedule growth and how schedule growth can be controlled. This paper attempts to quantify this percentage by looking at historical data and show detailed examples of how schedule growth influences cost growth. The paper also addresses a methodology to show an alternate approach for assessing and setting a robust baseline schedule and use schedule performance metrics to help assess if the project is performing to plan. Finally, recommendations are presented to help control schedule growth in order to minimize cost growth for NASA space science missions.

Comparing Pleasure and Pain: The Fundamental Mathematical Equivalence of Reward Gain and Shock Reduction under Variable Interval Schedules

ERIC Educational Resources Information Center

Mallpress, Dave E. W.; Fawcett, Tim W.; McNamara, John M.; Houston, Alasdair I.

2012-01-01

The relationship between positive and negative reinforcement and the symmetry of Thorndike's law of effect are unresolved issues in operant psychology. Here we show that, for a given pattern of responding on variable interval (VI) schedules with the same programmed rate of food rewards (positive reinforcement VI) or electric shocks (negative…

Alternatives for jet engine control

NASA Technical Reports Server (NTRS)

Sain, M. K.

1981-01-01

Research centered on basic topics in the modeling and feedback control of nonlinear dynamical systems is reported. Of special interest were the following topics: (1) the role of series descriptions, especially insofar as they relate to questions of scheduling, in the control of gas turbine engines; (2) the use of algebraic tensor theory as a technique for parameterizing such descriptions; (3) the relationship between tensor methodology and other parts of the nonlinear literature; (4) the improvement of interactive methods for parameter selection within a tensor viewpoint; and (5) study of feedback gain representation as a counterpart to these modeling and parameterization ideas.

Smart monitoring system based on adaptive current control for superconducting cable test.

PubMed

Arpaia, Pasquale; Ballarino, Amalia; Daponte, Vincenzo; Montenero, Giuseppe; Svelto, Cesare

2014-12-01

A smart monitoring system for superconducting cable test is proposed with an adaptive current control of a superconducting transformer secondary. The design, based on Fuzzy Gain Scheduling, allows the controller parameters to adapt continuously, and finely, to the working variations arising from transformer nonlinear dynamics. The control system is integrated in a fully digital control loop, with all the related benefits, i.e., high noise rejection, ease of implementation/modification, and so on. In particular, an accurate model of the system, controlled by a Fuzzy Gain Scheduler of the superconducting transformer, was achieved by an experimental campaign through the working domain at several current ramp rates. The model performance was characterized by simulation, under all the main operating conditions, in order to guide the controller design. Finally, the proposed monitoring system was experimentally validated at European Organization for Nuclear Research (CERN) in comparison to the state-of-the-art control system [P. Arpaia, L. Bottura, G. Montenero, and S. Le Naour, "Performance improvement of a measurement station for superconducting cable test," Rev. Sci. Instrum. 83, 095111 (2012)] of the Facility for the Research on Superconducting Cables, achieving a significant performance improvement: a reduction in the system overshoot by 50%, with a related attenuation of the corresponding dynamic residual error (both absolute and RMS) up to 52%.

A Mechanized Decision Support System for Academic Scheduling.

DTIC Science & Technology

1986-03-01

an operational system called software. The first step in the development phase is Design . Designers destribute software control by factoring the Data...SUBJECT TERMS (Continue on reverse if necessary and identify by block number) ELD GROUP SUB-GROUP Scheduling, Decision Support System , Software Design ...scheduling system . It will also examine software - design techniques to identify the most appropriate method- ology for this problem. " - Chapter 3 will

Job Scheduling in a Heterogeneous Grid Environment

NASA Technical Reports Server (NTRS)

Shan, Hong-Zhang; Smith, Warren; Oliker, Leonid; Biswas, Rupak

2004-01-01

Computational grids have the potential for solving large-scale scientific problems using heterogeneous and geographically distributed resources. However, a number of major technical hurdles must be overcome before this potential can be realized. One problem that is critical to effective utilization of computational grids is the efficient scheduling of jobs. This work addresses this problem by describing and evaluating a grid scheduling architecture and three job migration algorithms. The architecture is scalable and does not assume control of local site resources. The job migration policies use the availability and performance of computer systems, the network bandwidth available between systems, and the volume of input and output data associated with each job. An extensive performance comparison is presented using real workloads from leading computational centers. The results, based on several key metrics, demonstrate that the performance of our distributed migration algorithms is significantly greater than that of a local scheduling framework and comparable to a non-scalable global scheduling approach.

Reason's Enemy Is Not Emotion: Engagement of Cognitive Control Networks Explains Biases in Gain/Loss Framing

PubMed Central

2017-01-01

In the classic gain/loss framing effect, describing a gamble as a potential gain or loss biases people to make risk-averse or risk-seeking decisions, respectively. The canonical explanation for this effect is that frames differentially modulate emotional processes, which in turn leads to irrational choice behavior. Here, we evaluate the source of framing biases by integrating functional magnetic resonance imaging data from 143 human participants performing a gain/loss framing task with meta-analytic data from >8000 neuroimaging studies. We found that activation during choices consistent with the framing effect were most correlated with activation associated with the resting or default brain, while activation during choices inconsistent with the framing effect was most correlated with the task-engaged brain. Our findings argue against the common interpretation of gain/loss framing as a competition between emotion and control. Instead, our study indicates that this effect results from differential cognitive engagement across decision frames. SIGNIFICANCE STATEMENT The biases frequently exhibited by human decision makers have often been attributed to the presence of emotion. Using a large fMRI sample and analysis of whole-brain networks defined with the meta-analytic tool Neurosynth, we find that neural activity during frame-biased decisions was more significantly associated with default behaviors (and the absence of executive control) than with emotion. These findings point to a role for neuroscience in shaping long-standing psychological theories in decision science. PMID:28264981

Reason's Enemy Is Not Emotion: Engagement of Cognitive Control Networks Explains Biases in Gain/Loss Framing.

PubMed

Li, Rosa; Smith, David V; Clithero, John A; Venkatraman, Vinod; Carter, R McKell; Huettel, Scott A

2017-03-29

In the classic gain/loss framing effect, describing a gamble as a potential gain or loss biases people to make risk-averse or risk-seeking decisions, respectively. The canonical explanation for this effect is that frames differentially modulate emotional processes, which in turn leads to irrational choice behavior. Here, we evaluate the source of framing biases by integrating functional magnetic resonance imaging data from 143 human participants performing a gain/loss framing task with meta-analytic data from >8000 neuroimaging studies. We found that activation during choices consistent with the framing effect were most correlated with activation associated with the resting or default brain, while activation during choices inconsistent with the framing effect was most correlated with the task-engaged brain. Our findings argue against the common interpretation of gain/loss framing as a competition between emotion and control. Instead, our study indicates that this effect results from differential cognitive engagement across decision frames. SIGNIFICANCE STATEMENT The biases frequently exhibited by human decision makers have often been attributed to the presence of emotion. Using a large fMRI sample and analysis of whole-brain networks defined with the meta-analytic tool Neurosynth, we find that neural activity during frame-biased decisions was more significantly associated with default behaviors (and the absence of executive control) than with emotion. These findings point to a role for neuroscience in shaping long-standing psychological theories in decision science. Copyright © 2017 the authors 0270-6474/17/373588-11$15.00/0.

Control systems engineering for optimizing a prenatal weight gain intervention to regulate infant birth weight.

PubMed

Savage, Jennifer S; Downs, Danielle Symons; Dong, Yuwen; Rivera, Daniel E

2014-07-01

We used dynamical systems modeling to describe how a prenatal behavioral intervention that adapts to the needs of each pregnant woman may help manage gestational weight gain and alter the obesogenic intrauterine environment to regulate infant birth weight. This approach relies on integrating mechanistic energy balance, theory of planned behavior, and self-regulation models to describe how internal processes can be impacted by intervention dosages, and reinforce positive outcomes (e.g., healthy eating and physical activity) to moderate gestational weight gain and affect birth weight. A simulated hypothetical case study from MATLAB with Simulink showed how, in response to our adaptive intervention, self-regulation helps adjust perceived behavioral control. This, in turn, changes the woman's intention and behavior with respect to healthy eating and physical activity during pregnancy, affecting gestational weight gain and infant birth weight. This article demonstrates the potential for real-world applications of an adaptive intervention to manage gestational weight gain and moderate infant birth weight. This model could be expanded to examine the long-term sustainable impacts of an intervention that varies according to the participant's needs on maternal postpartum weight retention and child postnatal eating behavior.

Remote Collaboration on Task Scheduling for Humans at Mars

NASA Technical Reports Server (NTRS)

Jaap, John; Meyer, Patrick; Davis, Elizabeth; Richardson, Lea

2006-01-01

As humans venture farther from Earth for longer durations, it will become essential for those on the journey to have significant control over the scheduling of their own activities as well as the activities of their companion systems and robots. However, the crew will not do all the scheduling; timelines will be the result of collaboration with ground personnel. Emerging technologies such as in-space message buses, delay-tolerant networks, and in-space internet will be the carriers on which the collaboration rides. Advances in scheduling technology, in the areas of task modeling, scheduling engines, and user interfaces will allow the crew to become virtual scheduling experts. New concepts of operations for producing the timeline will allow the crew and the ground support to collaborate while providing safeguards to ensure that the mission will be effectively accomplished without endangering the systems or personnel.

Deconstructing Nowicki and Smutnickis i-TSAB tabu search algorithm for the job-shop scheduling problem.

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

Whitley, L. Darrell; Watson, Jean-Paul; Howe, Adele E.

Over the last decade and a half, tabu search algorithms for machine scheduling have gained a near-mythical reputation by consistently equaling or establishing state-of-the-art performance levels on a range of academic and real-world problems. Yet, despite these successes, remarkably little research has been devoted to developing an understanding of why tabu search is so effective on this problem class. In this paper, we report results that provide significant progress in this direction. We consider Nowicki and Smutnicki's i-TSAB tabu search algorithm, which represents the current state-of-the-art for the makespan-minimization form of the classical jobshop scheduling problem. Via a series ofmore » controlled experiments, we identify those components of i-TSAB that enable it to achieve state-of-the-art performance levels. In doing so, we expose a number of misconceptions regarding the behavior and/or benefits of tabu search and other local search metaheuristics for the job-shop problem. Our results also serve to focus future research, by identifying those specific directions that are most likely to yield further improvements in performance.« less

Conflict-Aware Scheduling Algorithm

NASA Technical Reports Server (NTRS)

Wang, Yeou-Fang; Borden, Chester

2006-01-01

conflict-aware scheduling algorithm is being developed to help automate the allocation of NASA s Deep Space Network (DSN) antennas and equipment that are used to communicate with interplanetary scientific spacecraft. The current approach for scheduling DSN ground resources seeks to provide an equitable distribution of tracking services among the multiple scientific missions and is very labor intensive. Due to the large (and increasing) number of mission requests for DSN services, combined with technical and geometric constraints, the DSN is highly oversubscribed. To help automate the process, and reduce the DSN and spaceflight project labor effort required for initiating, maintaining, and negotiating schedules, a new scheduling algorithm is being developed. The scheduling algorithm generates a "conflict-aware" schedule, where all requests are scheduled based on a dynamic priority scheme. The conflict-aware scheduling algorithm allocates all requests for DSN tracking services while identifying and maintaining the conflicts to facilitate collaboration and negotiation between spaceflight missions. These contrast with traditional "conflict-free" scheduling algorithms that assign tracks that are not in conflict and mark the remainder as unscheduled. In the case where full schedule automation is desired (based on mission/event priorities, fairness, allocation rules, geometric constraints, and ground system capabilities/ constraints), a conflict-free schedule can easily be created from the conflict-aware schedule by removing lower priority items that are in conflict.

Design of a candidate flutter suppression control law for DAST ARW-2. [Drones for Aerodynamic and Structural Testing Aeroelastic Research Wing

NASA Technical Reports Server (NTRS)

Adams, W. M., Jr.; Tiffany, S. H.

1983-01-01

A control law is developed to suppress symmetric flutter for a mathematical model of an aeroelastic research vehicle. An implementable control law is attained by including modified LQG (linear quadratic Gaussian) design techniques, controller order reduction, and gain scheduling. An alternate (complementary) design approach is illustrated for one flight condition wherein nongradient-based constrained optimization techniques are applied to maximize controller robustness.

Adjustment of Adaptive Gain with Bounded Linear Stability Analysis to Improve Time-Delay Margin for Metrics-Driven Adaptive Control

NASA Technical Reports Server (NTRS)

Bakhtiari-Nejad, Maryam; Nguyen, Nhan T.; Krishnakumar, Kalmanje Srinvas

2009-01-01

This paper presents the application of Bounded Linear Stability Analysis (BLSA) method for metrics driven adaptive control. The bounded linear stability analysis method is used for analyzing stability of adaptive control models, without linearizing the adaptive laws. Metrics-driven adaptive control introduces a notion that adaptation should be driven by some stability metrics to achieve robustness. By the application of bounded linear stability analysis method the adaptive gain is adjusted during the adaptation in order to meet certain phase margin requirements. Analysis of metrics-driven adaptive control is evaluated for a linear damaged twin-engine generic transport model of aircraft. The analysis shows that the system with the adjusted adaptive gain becomes more robust to unmodeled dynamics or time delay.

On Several Fundamental Problems of Optimization, Estimation, and Scheduling in Wireless Communications

NASA Astrophysics Data System (ADS)

Gao, Qian

compared with the conventional decoupled system with the same spectrum efficiency to demonstrate the power efficiency. Crucial lighting requirements are included as optimization constraints. To control non-linear distortion, the optical peak-to-average-power ratio (PAPR) of LEDs can be individually constrained. With a SVD-based pre-equalizer designed and employed, our scheme can achieve lower BER than counterparts applying zero-forcing (ZF) or linear minimum-mean-squared-error (LMMSE) based post-equalizers. Besides, a binary switching algorithm (BSA) is applied to improve BER performance. The third part looks into a problem of two-phase channel estimation in a relayed wireless network. The channel estimates in every phase are obtained by the linear minimum mean squared error (LMMSE) method. Inaccurate estimate of the relay to destination (RtD) channel in phase 1 could affect estimate of the source to relay (StR) channel in phase 2, which is made erroneous. We first derive a close-form expression for the averaged Bayesian mean-square estimation error (ABMSE) for both phase estimates in terms of the length of source and relay training slots, based on which an iterative searching algorithm is then proposed that optimally allocates training slots to the two phases such that estimation errors are balanced. Analysis shows how the ABMSE of the StD channel estimation varies with the lengths of relay training and source training slots, the relay amplification gain, and the channel prior information respectively. The last part deals with a transmission scheduling problem in a uplink multiple-input-multiple-output (MIMO) wireless network. Code division multiple access (CDMA) is assumed as a multiple access scheme and pseudo-random codes are employed for different users. We consider a heavy traffic scenario, in which each user always has packets to transmit in the scheduled time slots. If the relay is scheduled for transmission together with users, then it operates in a full

Controlling slow and fast light and dynamic pulse-splitting with tunable optical gain in a whispering-gallery-mode microcavity

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

Asano, M.; Ikuta, R.; Imoto, N.

We report controllable manipulation of slow and fast light in a whispering-gallery-mode microtoroid resonator fabricated from Erbium (Er{sup 3+}) doped silica. We observe continuous transition of the coupling between the fiber-taper waveguide and the microresonator from undercoupling to critical coupling and then to overcoupling regimes by increasing the pump power even though the spatial distance between the resonator and the waveguide was kept fixed. This, in turn, enables switching from fast to slow light and vice versa just by increasing the optical gain. An enhancement of delay of two-fold over the passive silica resonator (no optical gain) was observed inmore » the slow light regime. Moreover, we show dynamic pulse splitting and its control in slow/fast light systems using optical gain.« less

Automated telescope scheduling

NASA Technical Reports Server (NTRS)

Johnston, Mark D.

1988-01-01

With the ever increasing level of automation of astronomical telescopes the benefits and feasibility of automated planning and scheduling are becoming more apparent. Improved efficiency and increased overall telescope utilization are the most obvious goals. Automated scheduling at some level has been done for several satellite observatories, but the requirements on these systems were much less stringent than on modern ground or satellite observatories. The scheduling problem is particularly acute for Hubble Space Telescope: virtually all observations must be planned in excruciating detail weeks to months in advance. Space Telescope Science Institute has recently made significant progress on the scheduling problem by exploiting state-of-the-art artificial intelligence software technology. What is especially interesting is that this effort has already yielded software that is well suited to scheduling groundbased telescopes, including the problem of optimizing the coordinated scheduling of more than one telescope.

White Matter Microstructural Correlates of Superior Long-term Skill Gained Implicitly under Randomized Practice

PubMed Central

Song, Sunbin; Sharma, Nikhil; Buch, Ethan R.

2012-01-01

We value skills we have learned intentionally, but equally important are skills acquired incidentally without ability to describe how or what is learned, referred to as implicit. Randomized practice schedules are superior to grouped schedules for long-term skill gained intentionally, but its relevance for implicit learning is not known. In a parallel design, we studied healthy subjects who learned a motor sequence implicitly under randomized or grouped practice schedule and obtained diffusion-weighted images to identify white matter microstructural correlates of long-term skill. Randomized practice led to superior long-term skill compared with grouped practice. Whole-brain analyses relating interindividual variability in fractional anisotropy (FA) to long-term skill demonstrated that 1) skill in randomized learners correlated with FA within the corticostriatal tract connecting left sensorimotor cortex to posterior putamen, while 2) skill in grouped learners correlated with FA within the right forceps minor connecting homologous regions of the prefrontal cortex (PFC) and the corticostriatal tract connecting lateral PFC to anterior putamen. These results demonstrate first that randomized practice schedules improve long-term implicit skill more than grouped practice schedules and, second, that the superior skill acquired through randomized practice can be related to white matter microstructure in the sensorimotor corticostriatal network. PMID:21914632

High-speed low-power photonic transistor devices based on optically-controlled gain or absorption to affect optical interference.

PubMed

Huang, Yingyan; Ho, Seng-Tiong

2008-10-13

We show that a photonic transistor device can be realized via the manipulation of optical interference by optically controlled gain or absorption in novel ways, resulting in efficient transistor signal gain and switching action. Exemplary devices illustrate two complementary device types with high operating speed, microm size, microW switching power, and switching gain. They can act in tandem to provide a wide variety of operations including wavelength conversion, pulse regeneration, and logical operations. These devices could have a Transistor Figure-of-Merits >10(5) times higher than current chi((3)) approaches and are highly attractive.

77 FR 48551 - Records Schedules; Availability and Request for Comments

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-14

... agencies create billions of records on paper, film, magnetic tape, and other media. To control this... as permanent. The schedules listed in this notice are media neutral unless specified otherwise. An item in a schedule is media neutral when the disposition instructions may be applied to records...

Submarine watch schedules: underway evaluation of rotating (contemporary) and compressed (alternative) schedules.

PubMed

Duplessis, C A; Miller, J C; Crepeau, L J; Osborn, C M; Dyche, J

2007-01-01

With a desire to increase health, cognitive performance effectiveness, and quality of life for submarine watch-standers underway, we performed an evaluation comparing an alternative, compressed-work (ALT) schedule, designed to enhance circadian rhythm entrainment and sleep hygiene, to the contemporary submarine (SUB) forward rotating schedule, aboard the ballistic-missile submarine, USS Henry M. Jackson (SSBN-730 Gold). We assessed a compressed close-6 watch-schedule ("ALT") relative to the existing backward rotating 6-hr on, 12-hr off 18-hr watch schedule ("SUB") employed underway aboard submarines. We monitored 40 subjects' sleep, and temperature and salivary cortisol from 10 of the 40 for approximately two weeks on each respective schedule underway. The cortisol cosinor mesors (midline estimating statistic of rhythm), and amplitudes did not differ significantly between conditions. The temperature cosinor mesors, and the cosinor amplitude were not significantly different, while the cosine curve fit accounted for significantly more variance in the ALT condition than in the SUB condition. The SUB schedule garnered significantly more sleep (7.1 +/- 0.2 hours) than that of the ALTMID schedule (6.3 +/- 0.3 hours). Surveys revealed that 52% of respondents preferred the SUB schedule, 15% preferred the ALT, and 33% were either indifferent or submitted uninterpretable surveys. The ALT schedule was not superior to the existing SUB schedule by physiological or subjective measures and was incompatible to accommodating operational constraints.

Simulation of textile manufacturing processes for planning, scheduling, and quality control purposes

NASA Astrophysics Data System (ADS)

Cropper, A. E.; Wang, Z.

1995-08-01

Simulation, as a management information tool, has been applied to engineering manufacture and assembly operations. The application of the principles to textile manufacturing (fiber to fabric) is discussed. The particular problems and solutions in applying the simulation software package to the yarn production processes are discussed with an indication of how the software achieves the production schedule. The system appears to have application in planning, scheduling, and quality assurance. The latter being a result of the traceability possibilities through a process involving mixing and splitting of material.

Adaptive Robust Output Feedback Control for a Marine Dynamic Positioning System Based on a High-Gain Observer.

PubMed

Du, Jialu; Hu, Xin; Liu, Hongbo; Chen, C L Philip

2015-11-01

This paper develops an adaptive robust output feedback control scheme for dynamically positioned ships with unavailable velocities and unknown dynamic parameters in an unknown time-variant disturbance environment. The controller is designed by incorporating the high-gain observer and radial basis function (RBF) neural networks in vectorial backstepping method. The high-gain observer provides the estimations of the ship position and heading as well as velocities. The RBF neural networks are employed to compensate for the uncertainties of ship dynamics. The adaptive laws incorporating a leakage term are designed to estimate the weights of RBF neural networks and the bounds of unknown time-variant environmental disturbances. In contrast to the existing results of dynamic positioning (DP) controllers, the proposed control scheme relies only on the ship position and heading measurements and does not require a priori knowledge of the ship dynamics and external disturbances. By means of Lyapunov functions, it is theoretically proved that our output feedback controller can control a ship's position and heading to the arbitrarily small neighborhood of the desired target values while guaranteeing that all signals in the closed-loop DP control system are uniformly ultimately bounded. Finally, simulations involving two ships are carried out, and simulation results demonstrate the effectiveness of the proposed control scheme.

Web Publishing Schedule

EPA Pesticide Factsheets

Section 207(f)(2) of the E-Gov Act requires federal agencies to develop an inventory and establish a schedule of information to be published on their Web sites, make those schedules available for public comment. To post the schedules on the web site.

The Business Change Initiative: A Novel Approach to Improved Cost and Schedule Management

NASA Technical Reports Server (NTRS)

Shinn, Stephen A.; Bryson, Jonathan; Klein, Gerald; Lunz-Ruark, Val; Majerowicz, Walt; McKeever, J.; Nair, Param

2016-01-01

Goddard Space Flight Center's Flight Projects Directorate employed a Business Change Initiative (BCI) to infuse a series of activities coordinated to drive improved cost and schedule performance across Goddard's missions. This sustaining change framework provides a platform to manage and implement cost and schedule control techniques throughout the project portfolio. The BCI concluded in December 2014, deploying over 100 cost and schedule management changes including best practices, tools, methods, training, and knowledge sharing. The new business approach has driven the portfolio to improved programmatic performance. The last eight launched GSFC missions have optimized cost, schedule, and technical performance on a sustained basis to deliver on time and within budget, returning funds in many cases. While not every future mission will boast such strong performance, improved cost and schedule tools, management practices, and ongoing comprehensive evaluations of program planning and control methods to refine and implement best practices will continue to provide a framework for sustained performance. This paper will describe the tools, techniques, and processes developed during the BCI and the utilization of collaborative content management tools to disseminate project planning and control techniques to ensure continuous collaboration and optimization of cost and schedule management in the future.

Schedule Risk Assessment

NASA Technical Reports Server (NTRS)

Smith, Greg

2003-01-01

Schedule Risk Assessment needs to determine the probability of finishing on or before a given point in time. Task in a schedule should reflect the "most likely" duration for each task. IN reality, each task is different and has a varying degree of probability of finishing within or after the duration specified. Schedule risk assessment attempt to quantify these probabilities by assigning values to each task. Bridges the gap between CPM scheduling and the project's need to know the likelihood of "when".

76 FR 38210 - Records Schedules; Availability and Request for Comments

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-29

... create billions of records on paper, film, magnetic tape, and other media. To control this accumulation... permanent. The schedules listed in this notice are media neutral unless specified otherwise. An item in a schedule is media neutral when the disposition instructions may be applied to records regardless of the...

76 FR 35048 - Records Schedules; Availability and Request for Comments

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-15

... create billions of records on paper, film, magnetic tape, and other media. To control this accumulation... permanent. The schedules listed in this notice are media neutral unless specified otherwise. An item in a schedule is media neutral when the disposition instructions may be applied to records regardless of the...

76 FR 22924 - Records Schedules; Availability and Request for Comments

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-25

... create billions of records on paper, film, magnetic tape, and other media. To control this accumulation... permanent. The schedules listed in this notice are media neutral unless specified otherwise. An item in a schedule is media neutral when the disposition instructions may be applied to records regardless of the...

75 FR 70705 - Records Schedules; Availability and Request for Comments

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-18

... Federal agencies create billions of records on paper, film, magnetic tape, and other media. To control... records proposed as permanent. The schedules listed in this notice are media neutral unless specified otherwise. An item in a schedule is media neutral when the disposition instructions may be applied to...

Schedule Matters: Understanding the Relationship between Schedule Delays and Costs on Overruns

NASA Technical Reports Server (NTRS)

Majerowicz, Walt; Shinn, Stephen A.

2016-01-01

This paper examines the relationship between schedule delays and cost overruns on complex projects. It is generally accepted by many project practitioners that cost overruns are directly related to schedule delays. But what does "directly related to" actually mean? Some reasons or root causes for schedule delays and associated cost overruns are obvious, if only in hindsight. For example, unrealistic estimates, supply chain difficulties, insufficient schedule margin, technical problems, scope changes, or the occurrence of risk events can negatively impact schedule performance. Other factors driving schedule delays and cost overruns may be less obvious and more difficult to quantify. Examples of these less obvious factors include project complexity, flawed estimating assumptions, over-optimism, political factors, "black swan" events, or even poor leadership and communication. Indeed, is it even possible the schedule itself could be a source of delay and subsequent cost overrun? Through literature review, surveys of project practitioners, and the authors' own experience on NASA programs and projects, the authors will categorize and examine the various factors affecting the relationship between project schedule delays and cost growth. The authors will also propose some ideas for organizations to consider to help create an awareness of the factors which could cause or influence schedule delays and associated cost growth on complex projects.

Self-assembled DNA tetrahedral optofluidic lasers with precise and tunable gain control.

PubMed

Chen, Qiushu; Liu, Huajie; Lee, Wonsuk; Sun, Yuze; Zhu, Dan; Pei, Hao; Fan, Chunhai; Fan, Xudong

2013-09-07

We have applied self-assembled DNA tetrahedral nanostructures for the precise and tunable control of the gain in an optofluidic fluorescence resonance energy transfer (FRET) laser. By adjusting the ratio of the donor and the acceptor attached to the tetrahedral vertices, 3.8 times reduction in the lasing threshold and 28-fold enhancement in the lasing efficiency were demonstrated. This work takes advantage of the self-recognition and self-assembly capabilities of biomolecules with well-defined structures and addressability, enabling nano-engineering of the laser down to the molecular level.

Aspects of job scheduling

NASA Technical Reports Server (NTRS)

Phillips, K.

1976-01-01

A mathematical model for job scheduling in a specified context is presented. The model uses both linear programming and combinatorial methods. While designed with a view toward optimization of scheduling of facility and plant operations at the Deep Space Communications Complex, the context is sufficiently general to be widely applicable. The general scheduling problem including options for scheduling objectives is discussed and fundamental parameters identified. Mathematical algorithms for partitioning problems germane to scheduling are presented.

29 CFR 825.203 - Scheduling of intermittent or reduced schedule leave.

Code of Federal Regulations, 2013 CFR

2013-07-01

... OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee Leave Entitlements Under the Family and Medical Leave Act § 825.203 Scheduling of intermittent or reduced schedule leave. Eligible... leave intermittently or on a reduced leave schedule for planned medical treatment, then the employee...

29 CFR 825.203 - Scheduling of intermittent or reduced schedule leave.

Code of Federal Regulations, 2012 CFR

2012-07-01

... OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee Leave Entitlements Under the Family and Medical Leave Act § 825.203 Scheduling of intermittent or reduced schedule leave. Eligible... leave intermittently or on a reduced leave schedule for planned medical treatment, then the employee...

29 CFR 825.203 - Scheduling of intermittent or reduced schedule leave.

Code of Federal Regulations, 2011 CFR

2011-07-01

... OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee Leave Entitlements Under the Family and Medical Leave Act § 825.203 Scheduling of intermittent or reduced schedule leave. Eligible... leave intermittently or on a reduced leave schedule for planned medical treatment, then the employee...

29 CFR 825.203 - Scheduling of intermittent or reduced schedule leave.

Code of Federal Regulations, 2014 CFR

2014-07-01

... OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee Leave Entitlements Under the Family and Medical Leave Act § 825.203 Scheduling of intermittent or reduced schedule leave. Eligible... leave intermittently or on a reduced leave schedule for planned medical treatment, then the employee...

Users manual for flight control design programs

NASA Technical Reports Server (NTRS)

Nalbandian, J. Y.

1975-01-01

Computer programs for the design of analog and digital flight control systems are documented. The program DIGADAPT uses linear-quadratic-gaussian synthesis algorithms in the design of command response controllers and state estimators, and it applies covariance propagation analysis to the selection of sampling intervals for digital systems. Program SCHED executes correlation and regression analyses for the development of gain and trim schedules to be used in open-loop explicit-adaptive control laws. A linear-time-varying simulation of aircraft motions is provided by the program TVHIS, which includes guidance and control logic, as well as models for control actuator dynamics. The programs are coded in FORTRAN and are compiled and executed on both IBM and CDC computers.

Request-Driven Schedule Automation for the Deep Space Network

NASA Technical Reports Server (NTRS)

Johnston, Mark D.; Tran, Daniel; Arroyo, Belinda; Call, Jared; Mercado, Marisol

2010-01-01

The DSN Scheduling Engine (DSE) has been developed to increase the level of automated scheduling support available to users of NASA s Deep Space Network (DSN). We have adopted a request-driven approach to DSN scheduling, in contrast to the activity-oriented approach used up to now. Scheduling requests allow users to declaratively specify patterns and conditions on their DSN service allocations, including timing, resource requirements, gaps, overlaps, time linkages among services, repetition, priorities, and a wide range of additional factors and preferences. The DSE incorporates a model of the key constraints and preferences of the DSN scheduling domain, along with algorithms to expand scheduling requests into valid resource allocations, to resolve schedule conflicts, and to repair unsatisfied requests. We use time-bounded systematic search with constraint relaxation to return nearby solutions if exact ones cannot be found, where the relaxation options and order are under user control. To explore the usability aspects of our approach we have developed a graphical user interface incorporating some crucial features to make it easier to work with complex scheduling requests. Among these are: progressive revelation of relevant detail, immediate propagation and visual feedback from a user s decisions, and a meeting calendar metaphor for repeated patterns of requests. Even as a prototype, the DSE has been deployed and adopted as the initial step in building the operational DSN schedule, thus representing an important initial validation of our overall approach. The DSE is a core element of the DSN Service Scheduling Software (S(sup 3)), a web-based collaborative scheduling system now under development for deployment to all DSN users.

Single-Pass Serial Scheduling Heuristic for Eglin AFB Range Services Division Schedule

DTIC Science & Technology

2009-06-01

scheduling tool for this RCPSP. Research on a schedule improvement metaheuristic and coding of the complete algorithm is required before it can be...a schedule better by applying metaheuristic improvement algorithms to a feasible schedule after it is created. 2.5.1. Greedy Algorithm The...next available position, the algorithm will not utilize all the available range time and manpower. An improvement metaheuristic is required to

Optimizing Gestational Weight Gain With the Eating4Two Smartphone App: Protocol for a Randomized Controlled Trial.

PubMed

Davis, Deborah; Davey, Rachel; Williams, Lauren T; Foureur, Maralyn; Nohr, Ellen; Knight-Agarwal, Catherine; Lawlis, Tanya; Oats, Jeremy; Skouteris, Helen; Fuller-Tyszkiewicz, Matthew

2018-05-30

Approximately 50% of women gain excessive weight in pregnancy. Optimizing gestational weight gain is important for the short- and long-term health of the childbearing woman and her baby. Despite this, there is no recommendation for routine weighing in pregnancy, and weight is a topic that many maternity care providers avoid. Resource-intensive interventions have mainly targeted overweight and obese women with variable results. Few studies have examined the way that socioeconomic status might influence the effectiveness or acceptability of an intervention to participants. Given the scale of the problem of maternal weight gain, maternity services will be unlikely to sustain resource intensive interventions; therefore, innovative strategies are required to assist women to manage weight gain in pregnancy. The primary aim of the trial was to examine the effectiveness of the Eating4Two smartphone app in assisting women of all body mass index categories to optimize gestational weight gain. Secondary aims include comparing childbirth outcomes and satisfaction with antenatal care and examining the way that relative advantage and disadvantage might influence engagement with and acceptability of the intervention. This randomized controlled trial will randomize 1330 women to control or intervention groups in 3 regions of different socioeconomic status. Women will be recruited from clinical and social media sites. The intervention group will be provided with access to the Eating4Two mobile phone app which provides nutrition and dietary information specifically tailored for pregnancy, advice on food serving sizes, and a graph that illustrates women's weight change in relation to the range recommended by the Institute of Medicine. Women will be encouraged to use the app to prompt conversations with their maternity care providers about weight gain in pregnancy. The control group will receive routine antenatal care. Recruitment has commenced though the recruitment rate is slower