Science.gov (United States)

An optimal deployment pattern of flux mapping detectors for a Canada uranium-deuterium (CANDU)-600 pressurized heavy water reactor (PHWR) is determined by obtaining an optimal feedback relationship between flux measurements and zone controllers. The reactor core is modeled with a time-dependent two-group, two-dimensional diffusion equation, and flux perturbation are expressed by model expansions. The modal expansion coefficients are used as elements of the state vector representing the system dynamics. An optimal feedback matrix connecting the flux measurement vector to the control vector is derived by minimizing a quadratic performance index involving both the state and control vectors. We obtain the detector effectiveness in terms of the optimal feedback matrix and determine optimal detector ...

International Nuclear Information System (INIS)

Research highlights: ? Mathematical model represents a power system which consists of synchronous machine connected to infinite bus through transmission line. ? Power system stabilizer was designed based on optimal pole shifting controller. ? The system performances was tested through load disturbances at different operating conditions. ? The system performance with the proposed optimal pole shifting controller is compared with the conventional pole placement controller. ? The digital simulation results indicated that the proposed controller has a superior performance. -- Abstract: Power system stabilizer based on optimal pole shifting is proposed. An approach for shifting the real parts of the open-loop poles to any desired positions while preserving the imaginary parts is presented. In each step of this approach, it is required to solve a ...

Science.gov (United States)

Two branches of research are conducted in this thesis. The first deals with nonlinear combustion response as a mechanism for triggering combustion instabilities in solid rocket motors. A nonlinear wave equation is developed to study a wide class of combustion response functions to second-order in fluctuation amplitude. Conditions for triggering are derived from analysis of limit cycles, and regions of triggering are found in parametric space. Introduction of linear cross-coupling and quadratic self-coupling among the acoustic modes appears to be how the nonlinear combustion response produces triggering to a stable limit cycle. Regions of initial conditions corresponding to stable pulses were found, suggesting that stability depends on initial phase angle and harmonic content, as well as the composite amplitude, of the pulse. Also, dependence of nonlinear stability upon system parameters is considered. The second part of this thesis presents research for a ...

Energy Technology Data Exchange (ETDEWEB)

Abstracts are presented of 63 papers on the following topics: large-scale optimization, interior-point methods, algorithms for optimization, problems in control, network optimization methods, and parallel algorithms for optimization problems.

CERN Document Server

A major goal in optomechanics is to observe and control quantum behavior in a system consisting of a mechanical resonator coupled to an optical cavity. Work towards this goal has focused on increasing the strength of the coupling between the mechanical and optical degrees of freedom; however, the form of this coupling is crucial in determining which phenomena can be observed in such a system. Here we demonstrate that avoided crossings in the spectrum of an optical cavity containing a flexible dielectric membrane allow us to realize several different forms of the optomechanical coupling. These include cavity detunings that are (to lowest order) linear, quadratic, or quartic in the membrane's displacement, and a cavity finesse that is linear in (or independent of) the membrane's displacement. All these couplings are realized in a single device with extremely low optical loss and can be tuned over a wide range in situ; in particular, we find that ...

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

This work considers the problem of controlling multiple nonholonomic vehicles so that they converge to a scent source without colliding with each other. Since the control is to be implemented on simple 8-bit microcontrollers, fuzzy control rules are used to simplify a linear quadratic regulator control design. The inputs to the fuzzy controllers for each vehicle are the (noisy) direction to the source, the distance to the closest neighbor vehicle, and the direction to the closest vehicle. These directions are discretized into four values: Forward, Behind, Left, and Right, and the distance into three values: Near, Far, Gone. The values of the control at these discrete values are obtained based on the collision-avoidance repulsive forces and the change of variables that reduces the motion control problem of each ...

Science.gov (United States)

Advances in the development of several electrooptic shutter devices utilizing the quadratic electrooptic effect of lead lanthanum zirconate titanate (PLZT) ceramic wafers are described. Aperture sizes utilized in these PLZT devices ranged from 25 ..mu..m to 0.25 m. Practical applications of the shutters discussed in this paper include eye protection in military and industrial applications, a goggle-type device with dual synchronously operated PLZT shutters for use in a stereoscopic three-dimensional TV display, an electrically controlled variable density filter for use with vidicon tubes, a large-aperture photographic shutter for image motion compensation cameras, and a page composer for use in a holographic memory system.

Energy Technology Data Exchange (ETDEWEB)

This paper suggests how nonlinear periodic optimal control of a pumped storage plant can be realized. The control problem consists in maximization of the plant benefits over an operational period. An optimal control law is proposed, yielding a bang-off-bang mode of operation. An algorithm for numerical solution of the problem was developed, and its effectiveness was demonstrated by simulation experiments.

CERN Document Server

Particle Swarm Optimization technique offers optimal or suboptimal solution to multidimensional rough objective functions. In this paper, this optimization technique is used for designing fractional order PID controllers that give better performance than their integer order counterparts. Controller synthesis is based on required peak overshoot and rise time specifications. The characteristic equation is minimized to obtain an optimum set of controller parameters. Results show that this design method can effectively tune the parameters of the fractional order controller.

CERN Document Server

The Proportional-Integral-Derivative Controller is widely used in industries for process control applications. Fractional-order PID controllers are known to outperform their integer-order counterparts. In this paper, we propose a new technique of fractional-order PID controller synthesis based on peak overshoot and rise-time specifications. Our approach is to construct an objective function, the optimization of which yields a possible solution to the design problem. This objective function is optimized using two popular bio-inspired stochastic search algorithms, namely Particle Swarm Optimization and Differential Evolution. With the help of a suitable example, the superiority of the designed fractional-order PID controller to an integer-order PID controller is affirmed and a comparative study of the ...

Energy Technology Data Exchange (ETDEWEB)

A systematic optimization method of choosing the weighting matrix in linear optimal control system design, under the conditions of prespecified closed-loop dominant eigenvalue locations and feedback gain limit constraints, is presented in this paper. Studies show that with the proposed method one can obtain the desired weighting matrix very quickly and conveniently without the heavy burden of choosing a suitable weighting matrix by trail and error. This method can also easily achieve a reduced-order feedback control system. The linear optimal power system stabilizer designed by using the proposed method produces very good performance.

British Library Electronic Table of Contents (United Kingdom)

The main drawback of Ni/YSZ anode supports for solid oxide fuel cell application is their low tolerance to reducing and oxidizing (RedOx) atmosphere changes, owing to the Ni/NiO volume variation. This work describes a structured approach based on design of experiments for optimizing the microstructure for RedOx stability enhancement. A full factorial hypercube design and the response surface methodology are applied with the variables and their variation range defined as: (1) NiO proportion (40-60wt% of the ceramic powders), (2) pore-former proportion (0-30wt% corresponding to 0-64vol.%), (3) NiO particle size (0.5-8mm) and (4) 8YSZ particle size (0.6-9mm). To obtain quadratic response models, 25 different compositions were prepared forming a central composite design. The measured responses...

Energy Technology Data Exchange (ETDEWEB)

The detection of explosives is a notoriously difficult problem, especially at stand-off distances, due to their (generally) low vapor pressure, environmental and matrix interferences, and packaging. We are exploring optimal dynamic detection to exploit the best capabilities of recent advances in laser technology and recent discoveries in optimal shaping of laser pulses for control of molecular processes to significantly enhance the standoff detection of explosives. The core of the ODD-Ex technique is the introduction of optimally shaped laser pulses to simultaneously enhance sensitivity of explosives signatures while reducing the influence of noise and the signals from background interferents in the field (increase selectivity). These goals are being addressed by operating in an optimal nonlinear fashion, typically with a single shaped laser pulse inherently containing within it ...

International Nuclear Information System (INIS)

The heavy water reactor such as Wolsung No.1 and No.2 has a purification system to purify the reactor coolant. The control system regulates the coolant temperature to protect the ion exchanger. After the fuel exchanges of operating plant, the increase of the coolant pressure makes the purification temperature control difficult. In this paper, the controllability of the control dynamics of the purification system was analysed and the optimal parameters were proposed. To reduce the effects of the flow disturbance, the feedforward control structure was proposed and analysed.

Science.gov (United States)

We present an optimal control approach for the solidification process of a melt in a container. The process is described by a two phase Stefan problem with the free boundary (interface between the two phases) modelled as a graph. We control the evolution of the free boundary using the temperature on the container wall. The control goal consists in tracking a prescribed evolution of the free boundary. We achieve this goal by minimizing a appropriate cost functional. The resulting minimization problem is solved numerically by a steepest descent method with step size control, where the gradient of the cost functional is expressed in terms of the adjoint variables. Several numerical examples are presented which illustrate the performance of the method. The novelty of the approach presented consists in using a sharp interface model for the control of the free ...

Energy Technology Data Exchange (ETDEWEB)

An adaptive power system stabilizer (APSS) employing a new self-optimizing pole shifting control strategy and its application to a power system are described in this paper. Based on an identified model of the system, the control is computed by an algorithm which shifts the closed-loop poles of the system to some optimal locations inside the unit circle in the z-domain to minimize a given performance criterion. With the self-optimization property, outside intervention in the controller design procedure is minimized, thus simplifying the tuning procedure during commissioning. Also, a new method of calculating the variable forgetting factor in real-time parameter identification is discussed. Studies show that the proposed APSS can provide good damping of the power system over a wide operating range and significantly improve the dynamic performance of the system.

International Nuclear Information System (INIS)

The results for development of methods and computer programs for integrated optimization of parameters of perspective fast reactors are given. The possibilities of the program for the reactor campaign calculation are analysed. This program is based on utilisation of the Bubnov-Galerkin method and Wigner disturbance theory. The possibility of application of approximation methods for the optimization researches is discussed. The results of development of the programs for complex reactor computations with account of control rods system and change of physical parameters in the reactor campaign are discussed. (author).

British Library Electronic Table of Contents (United Kingdom)

An Otto cycle engine with internal and external irreversibilities of friction and heat leakage, in which the heat transfer between the working fluid and the environment obeys linear phenomenological heat transfer law [q ?? ?(T ?1)], is studied in this paper. The optimal piston motion trajectory for maximizing the work output per cycle is derived for the fixed total cycle time and fuel consumed per cycle. Optimal control theory is applied to determine the optimal piston trajectories for the cases of with and without piston acceleration constraint on each stroke and the optimal distribution of the total cycle time among the strokes. The optimal piston motion with acceleration constraint for each stroke consists of three segments, including initial maximum acceleration and final maximum decel...

British Library Electronic Table of Contents (United Kingdom)

In this work, we propose a conceptual distributed control framework for electrical grid integrated with distributed renewable energy generation systems in order to enable the development of the so-called ''smart electrical grid''. First, we introduce the key elements and their interactions in the proposed control architecture and discuss the design of the distributed control systems which are able to coordinate their actions to account for optimization considerations on the system operation. Subsequently, we focus on a specific wind/solar energy generation system connected to a reverse osmosis water desalination system and the electrical grid and design two supervisory predictive controllers via model predictive control to operate the integrated system taking into account short-term and lo...

British Library Electronic Table of Contents (United Kingdom)

This paper analyzes the F-policy M/M/1/K queueing system with working vacation and an exponential startup time. The F-policy deals with the issue of controlling arrivals to a queueing system, and the server requires a startup time before allowing customers to enter the system. For the queueing systems with working vacation, the server can still provide service to customers rather than completely stop the service during a vacation period. The matrix-analytic method is applied to develop the steady-state probabilities, and then obtain several system characteristics. We construct the expected cost function and formulate an optimization problem to find the minimum cost. The direct search method and Quasi-Newton method are implemented to determine the optimal system capacity K, the optimal thre...

Energy Technology Data Exchange (ETDEWEB)

Optimum plant operation can often be achieved by means of constraint control instead of model- based on-line optimization. This is because optimum operation is seldom at the top of the hill but usually at the intersection of constraints. This article describes the development of a constraint control system for a plant producing ethylbenzene (EB) by the Mobil/Badger Ethylbenzene Process. Plant optimization can be defined as the maximization of a profit function describing the economics of the plant. This function contains terms with product values, feedstock prices and operational costs. Maximization of the profit function can be obtained by varying relevant degrees of freedom in the plant, such as a column operating pressure or a reactor temperature. These degrees of freedom can be varied within the available operating margins of the plant.

Science.gov (United States)

A unified Nonhydrostatic Multiscale Model on the Arakawa B grid (NMMB) designed for a broad range of spatial and temporal scales has been under development within the Earth System Modeling Framework (ESMF) at the National Centers for Environmental Prediction (NCEP) as a part of the new National Environmental Modeling System (NEMS). The model follows the general modeling philosophy of the NCEP's WRF NMM grid-point regional dynamical core. The model uses the regular latitude-longitude grid for the global domain, and a rotated latitude-longitude grid in regional applications. The nonhydrostatic component of the model dynamics is introduced through an add-on module that can be turned on or off depending on resolution. The "isotropic" quadratic conservative finite-volume horizontal differencing employed in the model conserves a variety of basic and derived dynamical and quadratic quantities and preserves some important properties of differential ...

CERN Document Server

In this paper, using combinatorial and analytic methods, we prove an exact calculating formula on the $2m$-th power mean value of the generalized quadratic Gauss sums for $m\\geq 2$. This solves a conjecture of He and Zhang [`On the $2k$-th power mean value of the generalized quadratic Gauss sums', Bull. Korean Math. Soc. 48 (2011), No.1, 9-15].

Energy Technology Data Exchange (ETDEWEB)

In robotics inverse dynamics is a standard control concept for highly nonlinear multibody systems. It is shown, however, that inverse dynamics results in a high energy demand. Therefore, linear energy efficient state feedback controllers are designed in a way that a performance index representing the energy consumption is minimized. At the same time inequality constraints such as control error and limited input variables have to be met. For the control design an analytical solution by pole placement is presented as well as a numerical controller optimization. This control design includes small motions in the neighborhood of the operating point. Then, linear controllers are tested with respect to control error and energy consumption when undergoing large displacement motion. It is shown that linear ...

Energy Technology Data Exchange (ETDEWEB)

The effects of automation and optimization on the day-to-day activities of oil field operators are sketched in this lead-in editorial comment on a series of articles designed to provide an overview of the revolution that computers have brought to the petroleum industry. The articles that follow detail the role of databases in tracking production information, new system architectures based on common integrated data repositories that provide corporation-wide access, the way video and single-site supervisory control and data acquisition are combined to control wellsite production, and a case study about the integrated processes introduced by Wascana Energy to automate its fields.

Energy Technology Data Exchange (ETDEWEB)

The aim of this research is the design and implementation of a decentralized power system stabilizer (PSS) capable of performing well for a wide range of variations in system parameters and/or loading conditions. The framework of the design is based on Fuzzy Logic Control (FLC). In particular, the neuro-fuzzy control rules are derived from training three classical PSSs; each is tuned using GA so as to perform optimally at one operating point. The effectiveness and robustness of the designed stabilizer, after implementing it to the laboratory model, is investigated. The results of real-time implementation prove that the proposed PSS offers a superior performance in comparison with the conventional stabilizer. (author)

British Library Electronic Table of Contents (United Kingdom)

The management programs for invasive species have been proposed and implemented in many regions of the world. However, practitioners and scientists have not reached a consensus on how to control them yet. One reason is the presence of various uncertainties associated with the management. To give some guidance on this issue, we characterize the optimal strategy by developing a dynamic model of invasive species management under uncertainties. In particular, focusing on (i) growth uncertainty and (ii) measurement uncertainty, we identify how these uncertainties affect optimal strategies and value functions. Our results suggest that a rise in growth uncertainty causes the optimal strategy to involve more restrained removals and the corresponding value function to shift up. Furthermore, we also...

International Nuclear Information System (INIS)

The paper develops a new design procedure for simultaneous coordinated designing of the thyristor controlled series capacitor (TCSC) damping controller and power system stabilizer (PSS) in multi-machine power system. The coordinated design problem of PSS and TCSC damping controllers over a wide range of loading conditions is converted to an optimization problem with the time domain-based objective function that is solved by a particle swarm optimization (PSO) technique which has a strong ability to find the most optimistic results. By minimizing the proposed fitness function in which oscillatory characteristics between areas are included and thus the interactions among the TCSC controller and PSS under transient conditions in the multi-machine power system are improved. To ensure the robustness of the proposed stabilizers, the design process takes a wide range ...

Energy Technology Data Exchange (ETDEWEB)

This paper presents the application of H{infinity} control synthesis using LMI optimization method to power system stabilizer(PSS) design. Since power system is usually operated under circumstance of unmeasurable uncertainties and external disturbances, the improvement of small signal stability becomes one of the most important issue for securing system stability and preventing low frequency oscillation phenomena. The LMI optimized H{infinity} PSS provides robust performance and guarantees the internal stability under these operating conditions. The global optimal H{infinity} norm is found using LMI convex optimization method which is more systematic than standard two Riccati solution method. The design results are simulated for a case study. We verified that the LMI method shown the best performance characteristic among standard Riccati method and conventional lead/lag method. ...

Energy Technology Data Exchange (ETDEWEB)

Electric utilities are actively seeking ways of optimizing the economics of their operations by improving productivity and reducing time and money spent on maintenance. Iberdrola, a Spanish utility, is using advanced machine condition-monitoring technology to centralize control and maintenance of its hydropower projects as a means of achieving those goals. The company is using a blend of technologies to supervise their projects from a regional control center. The monitoring scheme makes use of data from on-line, machine-condition monitors, displays from in-plant audio asnd video equipment, and analysis from the control center`s SCADA system.

British Library Electronic Table of Contents (United Kingdom)

Abstract This study presents a review of distributed model predictive control (DMPC) strategies followed by recent studies conducted by the authors on the robustness of these strategies to model errors and a summary of future challenges in this area. The review identifies three key challenges for the successful application of DMPC: (i) the selection of optimal control structure for DMPC; (ii) the choice of a suitable coordination strategy among the controllers; and (iii) the robustness of DMPC strategies to model errors. Then, the study summarises recent developments related to the robustness of unconstrained and constrained DMPC algorithms. For the unconstrained case, a methodology that is based on the calculation of a performance index is proposed to balance the trade-off between perform...

Science.gov (United States)

Resistance exercise has been widely reported to have positive rehabilitation effects for patients with neuromuscular and orthopaedic conditions. This paper presents an optimal design of magneto-rheological fluid dampers for variable resistance exercise devices. Adaptive controls for regulating the resistive force or torque of the device as well as the joint motion are presented. The device provides both isometric and isokinetic strength training for various human joints.

CERN Document Server

We give a new Becchi-Rouet-Stora-Tyutin operator for the superstring. It implies a quadratic gauge-fixed action, and a new gauge-invariant action with first-class constraints.The infinite pyramid of spinor ghosts appears in a simple way through ghost gamma matrices.

British Library Electronic Table of Contents (United Kingdom)

This paper studies the pricing of variance swap derivatives with stochastic volatility by the control variate method. A closed form solution is derived for the approximate model with deterministic volatility, which plays the key role in the paper, and an efficient control variate technique is therefore proposed when the volatility obeys the log-normal process. By the analysis of moments for the underlying processes, the optimal volatility function in the approximate model is constructed. The numerical results show the high efficiency of our method; the results coincide with the theoretical results. The idea in the paper is also applicable for the valuation of other types of variance swap, options with stochastic volatility and other financial derivatives with multi-factor models.

International Nuclear Information System (INIS)

In radiation risk assessment it must be differentiated between somatic and genetic effect on the one hand as well as between stochastic and non-stochastic effect on the other. According to definitions of the ICRP report 26 the limit for the dose equivalent of all tissues prevents non-stochastic radiation effects. With stochastic radiation effects probably exist no threshold doses; therefore the ALARA principle must be applied concerning radiation protection. The individual risk by stochastic radiation effects in its linear, linear-quadratic and quadratic extrapolations, respectively, is discussed in detail. The effective stochastic dose equivalent (H/sub eff/) as well as collective dose and collective damage are outlined.

Energy Technology Data Exchange (ETDEWEB)

Sigma 1) examines ways to reduce the number of breakdowns of pressure-regulating stations and to minimize the energy consumed in warming the gas, 2) determines the optimal gas temperatures upstream from the pressure reduction, and 3) shows the dependence of energy consumption upon the water dewpoint. The method of calculating the optimal input temperature relies on Mollier's diagram. Tables and nomographs for natural gas and water dewpoint at 19/sup 0/F and 580 psi (-7/sup 0/C and 4 MPa) are useful in achieving the desired gas temperatures. Heating the regulators' control valves is important.

Energy Technology Data Exchange (ETDEWEB)

The production of many important commercial materials involves the evolution of a complex fluid through a cooling phase into a hardened product. Textile fibers, high-strength fibers(KEVLAR, VECTRAN), plastics, chopped-fiber compounds, and fiber optical cable are such materials. Industry desires to replace experiments with on-line, real time models of these processes. Solutions to the problems are not just a matter of technology transfer, but require a fundamental description and simulation of the processes. Goals of the project are to develop models that can be used to optimize macroscopic properties of the solid product, to identify sources of undesirable defects, and to seek boundary-temperature and flow-and-material controls to optimize desired properties.

Energy Technology Data Exchange (ETDEWEB)

Energy consumption of black coal mines in Poland and methods for energy conservation are evaluated. Organizational models of energy management in underground coal mining are discussed. Tasks for dispatcher service for energy consumption control in a coal mine are analyzed: control of energy supplies, control of energy consumption, evaluation of electrical failures and reliability of protection systems, recording accidents and analyzing their causes, optimization of power systems in underground mines. Problems associated with control of energy consumption in a coal mine with mechanized systems for coal mining and use of computerized control systems are discussed. Recommendations for reucing energy consumption in underground coal mining are made. 4 references.

Energy Technology Data Exchange (ETDEWEB)

The objective of this project was to implement a centralised data base of internal quality control in radiotherapy according to the criteria of the decree of A.f.s.s.a.p.s. (French agency of sanitary safety of health products on 27 july 2007, about the internal quality control of external radiotherapy facilities. The software on one year meets the objectives: compliance by comparison with A.f.s.s.a.p.s. criteria but particularly optimization of the centralisation and analysis of the internal quality controls. (N.C.)

CERN Document Server

This paper presents a set of robust PI tuning formulae for a first order plus dead time process using particle swarm optimization. Also, tuning formulae for an integrating process with dead time, which is a special case of a first order plus dead time process, is given. The design problem considers three essential requirements of control problems, namely load disturbance rejection, setpoint regulation and robustness of closed-loop system against model uncertainties. The primary design goal is to optimize load disturbance rejection. Robustness is guaranteed by requiring that the maximum sensitivity is less than or equal to a specified value. In the first step, PI controller parameters are determined such that the IAE criterion to a load disturbance step is minimized and the robustness constraint on maximum sensitivity is satisfied. Using a structure with two degrees of freedom which introduces an extra ...

Energy Technology Data Exchange (ETDEWEB)

Digital control technology using micro-processor is widely used in Factory Automation area since 1980`s. However, the D{sub 2}O Vapour Recovery System in Wolsung 1 N.P.P is controlled by mechanical timer without considering the moisture condition in the Reactor Building and bed temperature, because it was designed using analog technology of 1960`s. This leads to the inefficient system operation and low D{sub 2}O recovery rate in addition to the high internal dose rate of operator. The goal of this phase II study is to develope a optimal automatic controller of D{sub 2}O vapour recovery system using PLC. We developed a control algorithm for Dual Tower Drier, a PLC control program, a operation change program and the monitoring system with a real-time simulator for system verification. (author). 15 refs., 11 figs., 2 tabs.

Energy Technology Data Exchange (ETDEWEB)

This paper presents a technique for speed control three-phase induction motor using the pulse width modulation (PWM), in open loop while maintaining the tension for constant frequency. The technique is adapted from a thesis entitled 'Control of the three-phase induction motor, using discrete PWM generation, optimized and synchronized', where studies are presented aimed at their application in home appliances, to eliminate mechanical parts, replaced by low cost electronic control, thus having a significant reduction in power consumption. Initially the experiment was done with the Intel 80C31 micro controller. In this paper, the PWM modulation is implemented using a PIC micro controller, and the speed control kept a low profile, based on tables, synchronized with transitions and reduced generation of harmonics in the network. ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Lyme neuroborreliosis (LNB) is a serious but treatable disease. The diagnosis of LNB poses a challenge to clinicians, and improved tests are needed. The C6-peptide ELISA is frequently used on serum but not on cerebrospinal fluid (CSF). Data on the sensitivity of the C6-peptide ELISA in CSF in patients suffering from LNB have been conflicting. Serum-CSF pairs from 59 LNB patients, 36 Lyme non-neuroborreliosis cases, 69 infectious meningitis/encephalitis controls and 74 neurological controls were tested in a C6-peptide ELISA. With the optimal cut-off of 1.1, the sensitivity of the C6-peptide ELISA for LNB patients in CSF was 95%, and the specificity was 83% in the Lyme non-neuroborreliosis patients, 96% in the infectious controls, and 97% in the neurological controls. These results ...

International Nuclear Information System (INIS)

In this paper, a neural networks (NN) based adaptive sliding mode controller (SMC) is introduced. The selection of SMC feedback gains is normally based on one operating point and thus the performance of the controller away from the design operating point is, of necessity, a compromise. The adaptive SMC is proposed to overcome the limitations imposed on the effectiveness of the SMC under different operating conditions. Neural networks are used for online prediction of the optimal SMC gains when the operating point changes. The proposed method has been applied to a power system stabilizer (PSS) of a single machine power system. Simulation results are included to demonstrate the performance of the proposed control scheme.

Energy Technology Data Exchange (ETDEWEB)

Canada's oil sands contain the largest known reserve of oil in the world. Oil sands mining uses 3 functional processes, ore hauling, overburden removal and mechanical maintenance. The industry relies mainly on truck-and-shovel technology in its open-pit mining operations which contributes greatly to the overall mining operation cost. Coordination between operating units is crucial for achieving an enterprise-wide optimal operation level. Some of the challenges facing the industry include multiple or conflicting objectives such as minimizing the use of raw materials and energy while maximizing production. The large sets of constraints that define the feasible domain pose as challenge, as does the uncertainty in system parameters. One solution lies in assigning truck resources to various activities. This fully decentralized approach would treat the optimization of ore production, waste removal and equipment maintenance independently. It ...

Science.gov (United States)

This workshop covered the latest practical engineering and operational management applications and techniques that have been found to enhance operational costs, reliability, and flexibility, with topics such as establishing the optimal refrigeration design cycle and operating design points; utility management; manpower scheduling; plant control philosophy and automation; short and long term maintenance scheduling; refrigerant loss detection and control; system contamination; component reliability; and equipment technical performance issues.

CERN Document Server

System identification is a necessity in control theory. Classical control theory usually considers processes with integer order transfer functions. Real processes are usually of fractional order as opposed to the ideal integral order models. A simple and elegant scheme is presented for approximation of such a real world fractional order process by an ideal integral order model. A population of integral order process models is generated and updated by PSO technique, the fitness function being the sum of squared deviations from the set of observations obtained from the actual fractional order process. Results show that the proposed scheme offers a high degree of accuracy.

Energy Technology Data Exchange (ETDEWEB)

The multi-spray direct injection diesel engine has the best efficiency of all combustion systems. The optimization of the air-fuel mixture parameters, especially of the fuel injection, enables the forming of the combustion process in a way, that all requirements and legislative regulations concerning power output, noise and exhaust emissions can be fulfilled. Electronic controlled unit injector systems, as developed by Voest-Alpine Automotive GmbH, Linz, offer the necessary potential to meet the complex requirements.

Energy Technology Data Exchange (ETDEWEB)

The systems analyses and optimization studies performed in connection with a program to design and evaluate a commercial 663 MWe coal-fired combined cycle power plant using pressurized fluidized bed combustion and advanced technology in the hot gas cleanup system and gas turbines are presented. Details on the plant control system are included. (LCL)

UK PubMed Central (United Kingdom)

The leukocyte-enriched p110γ and p110δ isoforms of PI3K have been shown to control in vitro degranulation of mast cells induced by cross-linking...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Recent research has shown that biologically inspired approaches to materials synthesis and self-assembly, hold promise of unprecedented atomic level control of structure and interfaces. In particular, the use of organic molecules to control the production of inorganic technological materials has the potential for controlling grain structure to enhance material strength; controlling facet expression for enhanced catalytic activity; and controlling the shape of nanostructured materials to optimize optical, electrical and magnetic properties. In this work, we use organic molecules to modify silver crystal shapes towards understanding the metal-organic interactions that lead to nanoparticle shape control. Using in situ electrochemical AFM (EC-AFM) as an in situ probe, we study the influence of a cationic surfactant cetyltrimethylamminobromide ...

Science.gov (United States)

The fuel cell control problem was studied. Attempts were made to control the output current of the fuel cell by starving it of hydrogen and oxygen. The motivation of this work was to increase efficiency by minimizing waste of fuel. The following findings were obtained: H2 starvation works better than O2 starvation; An optimal H2 to O2 ratio exists for combined H2&O2 starvation; The control scheme for H2&O2 starvation works well for 3 different disturbance tests and at 25 degrees C, 60 degrees C, and 80 degrees C; Fuel cell under reactant starvation is stable for at least 72 hrs.

CERN Document Server

Calculations relating to two experiments that demonstrate coherent control of preformed rubidium-85 molecules in a magneto-optical trap using ultrafast laser pulses are presented. In the first experiment, it is shown that pre-associated molecules in an incoherent mixture of states can be made to oscillate coherently using a single ultrafast pulse. A novel mechanism that can transfer molecular population to more deeply bound vibrational levels is used in the second. Optimal parameters of the control pulse are presented for the application of the mechanism to molecules in a magneto-optical trap. The calculations make use of an experimental determination of the initial state of molecules photoassociated by the trapping lasers in the magneto-optical trap and use shaped pulses consistent with a standard ultrafast laser system.

British Library Electronic Table of Contents (United Kingdom)

The environmental impact caused by local people (ecological footprint of consumption, EFc) and the actual environmental impact that the ecosystem burdens (ecological footprint of production, EFp) in West Jilin Province, Northeast China from 1986 to 2006 were evaluated by using ecological footprint (EF) method. And the major driving forces of EFc and EFp were analyzed by STIRPAT model. Both EFc and EFp showed increasing trends in 1986?2006, accompanied by decreasing ecological deficits but expanding ecological overshoots. Population (P), GDP per capita (A 1), quadratic term of GDP per capita (A 2), urbanization (T a1), and quadratic term of urbanization (T a2) were important influencing factors of EFc, among which T a2 and T a1 were the most dominate driving forces of EFc. A 1, A 2 and T a2...

International Nuclear Information System (INIS)

In this paper, research on pass schedule of tandem cold mill (TCM) is carried out. According to load (reduction, rolling force, motor power) balance, non-linear equations set with variables of inter-stand thickness is constructed. The pass schedule optimization is carried out by solving the non-linear equations set. As the traditional method, the Newton-Raphson method is used for solving the non-linear equations set. In this paper a new simple method is brought up. On basis of the monotone relations between thickness and load, the inter-stands thickness is adjusted dynamically. The solution of non-linear equations set can be converged by iterative calculation. This method can avoid the derivative calculation used by traditional method. So, this method is simple and calculation speed is high. It is suitable for on-line control. (author)

Energy Technology Data Exchange (ETDEWEB)

A new class of low aspect ratio toroidal hybrid stellarators is found using more general plasma confinement optimization criterion than quasi-symmetrization. The plasma current profile and shape of the outer magnetic flux surface are used as control variables to achieve near constancy of the longitudinal invariant J* on internal flux surfaces (quasi-omnigeneity), in addition to a number of other desirable physics target properties. We find that a range of compact (small aspect ratio A), high {beta} (ratio of thermal energy to magnetic field energy), low plasma current devices exist which have significantly improved confinement both for thermal as well as energetic (collisionless) particle components. With reasonable increases in magnetic field and geometric size, such devices can also be scaled to confine 3.5 MeV alpha particle orbits.

Science.gov (United States)

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CERN Document Server

Classical control theory has played a major role in the development of present-day technologies. Likewise, recently developed quantum optimal control methods can be applied to emerging quantum technologies, e.g. quantum information processing -- until now, at the level of a few qubits. However, such methods encounter severe limits when applied to many-body quantum systems: due to the complexity of simulating the latter, existing quantum control algorithms (requiring many iterations to converge) usually fail to yield a desired final state within an acceptable computational time. In contrast, we present here a strategy for controlling a vast range of non-integrable one-dimensional systems that is efficiently applicable to quantum many-body systems, as it can be merged with state-of-the-art tensor network simulation methods like the Density Matrix Renormalization Group. To demonstrate ...

Energy Technology Data Exchange (ETDEWEB)

A pole placement technique for power system stabilizer (PSS) and thyristor controlled series capacitor (TCSC) based stabilizer using simulated annealing (SA) algorithm is presented in this paper. The proposed approach employs SA optimization technique to PSS (SAPSS) and TCSC-based stabilizer (SACSC) design. The design problem is formulated as an optimization problem where SA is applied to search for the optimal setting of the proposed SAPSS and SACSC parameters. A pole placement-based objective function to shift the dominant eigenvalues to the left in the s-plane is considered. The proposed SAPSS and SACSC have been examined on a weakly connected power system with different disturbances, loading conditions, and system parameter variations. Eigenvalue analysis and nonlinear simulation results show the effectiveness and the robustness of the proposed stabilizers and their ability to provide efficient ...

Science.gov (United States)

A butterfly valve is a type of flow control device, typically used to regulate a fluid flowing. Currently, FEA is often used to predict the safety in the design of valve disc. Also, the study about the affection of butterfly valve's disc to the valve flow characteristics by using CFD has been done by many researchers. Along with the development of computer technique, design and analysis of computer experiments has becoming more and more important in engineering design and optimization. Hereinto Kriging model is one popular analysis approach for the purpose of creating a cheap ``meta-model'' as a surrogate to a computationally expensive simulation model. In this paper, the numerical analysis considered the strength, pressure loss coefficient and weight of valve disc simultaneously is investigated to improve the shape of a traditional butterfly valve disc. Firstly, an initial model of butterfly valve is made to evaluate the performance of the ...

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The reliability of the surface condenser is a key factor in plant performance level and maintenance cost optimization. This is especially the case for thermal nuclear plants where condenser raw wa-ter ingress can introduce contamination into the chemically-controlled, steam/water loop potentially causing damage to sensitive equipment. Two important parameters must be taken into account when attempting to optimize the quality and the reliability of condenser tubing. They include selecting the appropriate material according to the cooling water corrosion level present. A second and equally important parameter is the manufac-turing of the tubing product itself. This paper will identify methods to optimize manufacturing processes and improve tubing quality, according to VALTIMET's 30 years of condenser welded tubing production experience. Those methods complete the core manufacturing process ...

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The hierarchy of integrable nonlinear equations associated with the quadratic bundle is considered. The expressions for the solution of linearization of these equations and their conservation law in the terms of solutions of corresponding Lax pairs are found. It is shown for the first member of the hierarchy that the conservation law is connected with the solution of linearized equation due to the Noether's theorem. The local hierarchy and three nonlocal ones of the infinitesimal symmetries and conservation laws explicitly expressed through the variables of the nonlinear equations are derived. (author)

International Nuclear Information System (INIS)

By using linearized conformal transformations in six dimensions, a new unified approach to bradyons (v"2< c"2) and tachyons (v"2>c"2) is suggested, the essential tool being (real and imaginary) dilatations. The usual ''Generalized Lorentz transformations'' are got, In six dimensions the quadrate form is always positive, both for bradyons and for tachyons.

Energy Technology Data Exchange (ETDEWEB)

The main objectives of Phase 2 are to determine the feasibility of using cements with controlled particle size distributions (CPSD cements) in practical concrete applications, and to refine our estimates of the potential energy savings that may ensue from such use. The work in Phase 2 is divided into two main tasks, some parts of which will be carried out simultaneously: Task 1 will continue cement paste studies to optimize cement performance similar to those of Phase 1, but with particular emphasis on gypsum requirements, blended cements, and water-reducing admixtures. This task will also include preparation of sufficient CPSD cements for use in all Phase 2 work. Task 2 will be a comprehensive examination of the properties of concretes made with CPSD cements. This will include optimization of concrete mix designs to obtain the best possible performance for practical applications of both portland and blended cements. The ...

Science.gov (United States)

Solid solution-strengthened nickel base alloys have been used for nuclear stream generator tubing in pressurized water reactors since the beginnings of commercial nuclear power. The purpose of this paper is to recap and update the authors understanding of the relationship between processing, resulting structure, and properties for Alloy 600 and to discuss the requirements for optimized performance in both primary and secondary environments. Potential replacement materials and their performance will be discussed. Also discussed is the role and importance of system chemistry, bulk and local, and control and its relationship to performance. A discussion of potential mechanisms of environmentally assisted failure is also discussed.

International Nuclear Information System (INIS)

Evaluation of the tolerance limits of X-ray image density accepted by the radiologist shows that for different kinds of examinations, deviations of more than 50% from optimal density lead to images which cannot be used diagnostically. Within this range diagnostic accuracy shows a distinct maximum and diminishes to the limits by 20%. These figures are related to differences in the intensifying factor of screens, sensitivity of films, sensitometric parameters of film processing as well as the doses employed with automatic exposure control devices, measured in clinical conditions. Maximum permissible tolerance limits of the whole imaging system and of its constituents are discussed using the Gaussian law of error addition. (author).

British Library Electronic Table of Contents (United Kingdom)

Innate immune responses are regulated by microorganisms and cell death, as well as by a third class of stress signal from the nervous and endocrine systems. The innate immune system also feeds back, through the production of cytokines, to regulate the function of the central nervous system (CNS), and this has effects on behaviour. These signals provide an extrinsic regulatory circuit that links physiological, social and environmental conditions, as perceived by the CNS, with transcriptional 'decision-making' in leukocytes. CNS-mediated regulation of innate immune responses optimizes total organism fitness and provides new opportunities for therapeutic control of chronic infectious, inflammatory and neuropsychiatric diseases.

International Nuclear Information System (INIS)

The partial project SR 2039/4 investigates organizational demands and factors of the man-organization interface. Thee study is divided into the sections inventory of rules and guidelines; evaluation of organizational structures and modes of operation, and working out of demand characteristics and evaluation criteria. The objective consists in representing, analyzing and evaluating the efficiency structure of sequence organization, and deriving practice-relevant concept proposals in order to optimize the man-organization interface. In this regard, the working out of control mechanisms for the evaluation of organizational sequences is of considerable importance as a kind of working aid. (orig./DG).

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Objective was to develop a mathematical model of the cupola furnace (cast iron production) in on-line and off-line process control and optimization. In Phase I, the general structure of the heat transfer, fluid flow, and chemical models were laid out, providing reasonable descriptions of cupola behavior with a one-dimensional representation. Work was also initiated on a two-dimensional model. Phase II was focused on perfecting the one-dimensional model. The contributions include these from MIT, Michigan University, and GM.

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For the purpose of optimizing the process of co-implantation of MeV Si ions to reduce boron transient enhanced diffusion and boron-enhanced diffusion in Si, multiple MeV implantations and annealing at different temperatures have been performed. A slight improvement on the suppression of B diffusion is observed by adding a low temperature annealing step after the MeV implantation. No differences in B diffusion are observed when the Si doses are increased from 1 x 10{sup 15} to 1 x 10{sup 16} cm{sup -2}. This dose independent behavior is speculated to be a quasi-steady state of vacancy cluster evaporation.

International Nuclear Information System (INIS)

Both microstructural graded and homogenous single-phase #alpha#-Sialon is obtained from Si_3N_4 powder for a broad range of compositions of practical interest. Elongated grains of #alpha#-Sialon could be developed in the monophase material by controlled mechanism of nucleation and growth. Tailoring of microstructure was realized through slow transformation reaction from Si_3N_4 to #alpha#-Sialon at lower temperature than sintering temperature when the composition is near the #alpha#-Sialon phase boundary. The mechanical properties are strongly correlated with the microstructure and are enhanced greatly in the optimized Sialon composition. (author)

International Nuclear Information System (INIS)

Despite high local control rate in Ewing's sarcoma the exact indication of radiation therapy is still controversial as well as the choice of the target volume and the optimal dose of radiation. The importance of the quality of radiotherapy has been stressed in recently published data and has shown a significant impact on long term local control with adequate radiation therapy. The dramatic improvement of precision allowed by the conformal therapy and three dimensional dosimetry allow to expect a decrease of late effects expected for second malignancies. However, late sequelae and radio-induced osteosarcoma still remain the major side effects after radiotherapy. The authors discuss the results of the main trials on Ewing's sarcoma on the choice of dose and target volume. Surgery is still the preferred choice for small tumors if the foreseen outcome is identical. (authors). 28 refs.

International Nuclear Information System (INIS)

The dynamical decoupling (DD) aims at suppressing the decoherence by means of coherent control pulses. Even if devices exist where instantaneous pulses are an adequate approximation, experimentally a finite duration #tau#_p and a bounded amplitude are inevitable. They are the cause of additional errors which can be corrected by designing the pulse shape appropriately. The new pulse has the overall effect of an ideal, instantaneous pulse with the advantage of decoupling the spin (or qubit) from the bath up to the order O(#tau#_p"3). The limitation of the no-go theorem for #pi# pulses is avoided. Hence, the Uhrig sequence (UDD), originally thought for ideal #pi# pulses, works also for bounded control Hamiltonians. Numerical simulations show that concatenated sequences of real pulses are effective against general decoherence.

British Library Electronic Table of Contents (United Kingdom)

Tissue hypoxia is a feature of cancer, heart disease and stroke, and imaging it may become clinically important. Copper-ATSM (ATSMH2 = 2,3-butanedione bis(N-methyl)thiosemicarb-azone), labelled with 60Cu, 62Cu or 64Cu, is selectively taken up in hypoxic cells in vitro and in vivo by a bioreductive mechanism, and is a prototype hypoxia imaging agent amenable to improvement. In vitro studies with several differently alkylated analogues of CuATSM show that hypoxia selectivity is a general property of complexes with two alkyl groups at the diketone backbone, offering a range of pharmacokinetic properties while retaining hypoxia selectivity. This pharmacokinetic control affords a route to development of second-generation hypoxia imaging agents with optimized properties for different clinical ap...

CERN Document Server

System identification refers to estimation of process parameters and is a necessity in control theory. Physical systems usually have varying parameters. For such processes, accurate identification is particularly important. Online identification schemes are also needed for designing adaptive controllers. Real processes are usually of fractional order as opposed to the ideal integral order models. In this paper, we propose a simple and elegant scheme of estimating the parameters for such a fractional order process. A population of process models is generated and updated by particle swarm optimization (PSO) technique, the fitness function being the sum of squared deviations from the actual set of observations. Results show that the proposed scheme offers a high degree of accuracy even when the observations are corrupted to a significant degree. Additional schemes to improve the accuracy still further are also proposed and ...

Energy Technology Data Exchange (ETDEWEB)

Monitoring brine chemistry to determine the extent of potential adverse reactions has been simplified by the development of a field-brine test kit and a series of nomographs. Results of the kit analyses serve as input to the nomographs, which provide a graphic means of determining the scaling tendency (Saturation Index value) of a brine. Brines that do not tend to form scale may be corrosive. Saturation Index values were correlated with various processes using data from geopressured wells in the Gulf Coast area. Control of scale in surface equipment with chemical inhibitors has been successful. Numerous laboratory simulations of inhibitor squeeze operations were completed using core material with calcite present and absent. The corresponding wells were squeezed with phosphorous-containing inhibitors, and the flowback of brine was monitored for phosphorous concentrations vs time. A new procedure to measure the concentration of phosphorous-containing inhibitors down ...

International Nuclear Information System (INIS)

This paper is a progress report on the role of radiation therapy (RT) in local tumor control and the decreased incidence of pulmonary metastasis in 251 patients entered in the Intergroup Ewing's Sarcoma Study. All were followed for more that 1 year, and their RT records were reviewed. Doses to the primary tumor in the range of 4,500--6,500 rad were administered over approximately 5 to 6 weeks in combination with 4 drugs, i.e., vincristine (VCR), dactinomycin (DAC), cyclophosphamide (CY), and adriamycin, or only the first 3. One group of patients received the 3 drugs and bilateral pulmonary irradiation (approximately 1,500 rad in 2 wk). Preliminary analysis showed a local primary tumor control of approximately 90%. Patients with lesions in the pelvis and humerus had local failure rates of 13% (7 of 54) and 21.4% (6 of 28), respectively. The treatment groups differed significantly in the incidence of pulmonary metastasis. Patients treated with ...

Science.gov (United States)

The safety of tissue allografts has come under increased scrutiny due to recent reports of allograft-associated bacterial and viral infections in tissue recipients. We report that 50 kGy of gamma irradiation, nearly three times the dose currently used, is an effective pathogen inactivation method when used under optimized conditions that minimize damage to the tissue. Cancellous bone dowels treated with a radioprotectant solution and 50 kGy of optimized irradiation had an ultimate compressive strength and modulus of elasticity equal to conventionally irradiated (18 kGy) and non-irradiated control bone grafts. We subjected bone dowels treated with this pathogen inactivation method to an in vitro cytotoxicity test using three different mammalian cell lines and concluded that the treated grafts were not cytotoxic. The log reduction of nine pathogens spiked into radioprotectant-treated bone irradiated to 50 kGy was also tested. ...

Energy Technology Data Exchange (ETDEWEB)

The complete determination of stroke/throughput curves at steam turbines for arbitrary valve positions usually only follows after the fundamental layout of the control valves, of the possible nozzle segments and of the turbine blading. A general fundamental equation and some design norms based on it are presented which may serve already before a fluidic layout of the turbine in detail as an optimizing predetermination of the properties concerning pressure loss and control statics of the metering components in the admission area. (orig.) [Deutsch] Die vollstaendige Bestimmung der Hub-/Durchsatzkurven an Dampfturbinen fuer beliebige Ventilstellungen erfolgt ueblicherweise erst nach der Grundauslegung der Stellventile, etwaiger Duesensegmente und der Turbinenbeschaufelung. Es werden eine allgemeine Grundgleichung und einige auf ihr aufbauende Entwurfsregeln angegeben, die zu einer optimierenden Vorabbestimmung der ...

International Nuclear Information System (INIS)

KAERI (Korea Advanced Energy Research Institute) has performed research to develop the fabrication technology of CANDU nuclear fuel since 1981. Based on the satisfactory results of in-pile and out-of-pile tests of prototype nuclear fuel and the outstanding performance of 48 KAERI-made nuclear fuels in Wolsung(CANDU) power reactor, Korean government decided KAERI to supply all the nuclear fuels for Wolsung from 1988. In order to guarantee the safety and performance of nuclear fuel manufactured in mass production scale, well-organized quality assurance system and appropriate quality control techniques should be established. To establish the QA system, KAERI reviewed various QA standards and decided to establish QA system based on the 10 CFR 50 Appendix B. Quality control techniques was also revised to fit the mass production even though quality inspection techniques have already been developed during research period. By applying statistical ...

Science.gov (United States)

An experimental investigation was conducted to determine the feasibility of machining isogrid structures with abrasive-waterjets (AWJs). The main objective was to mill isogrid patterns in surfaces with accurate depth control using an AWJ. Three different approaches using AWJs were tested: linear cutting of isogrid patterns for diffusion bonding, milling with conventional AWJ nozzles, and milling with a single-angled rotary AWJ nozzle. It was shown that pocket milling with conventional AWJs is the most feasible of those tested. The milling can be done internally on preformed aluminum tubes, and the AWJ can also be used on materials other than aluminum. Accurate depth control can be achieved at high productivity rates. As an example, it is projected that a 48-inch-diameter skirt 12 inches high could be milled with an isogrid pattern in 6.3 hours. Milled isogrid patterns can be controlled to 0.001 inch, and thin walls of less ...

Energy Technology Data Exchange (ETDEWEB)

We numerically constructed elementary phase-correct global quantum gates by using molecular electronic and vibrational states to encode two qubits and implement the Deutsch-Jozsa algorithm. The calculations were based on optimal control theory (OCT). The molecular species we chose were Na{sub 2} and Li{sub 2}. The electronic X{sup 1}{sigma}{sub g}{sup +} and A{sup 1}{sigma}{sub u}{sup +} states were taken as two orthonormalized energy levels of the electronic qubit. The vibrational qubits were those involved in these electronic states. The time duration of the optimized pulses with high fidelity was typically 500-900 fs, which reflects the wavepacket dynamics in electronically ground and excited states. When implementing the Deutsch-Jozsa algorithm by combining these elementary gates, we obtained a maximum probability 83.12% for Li{sub 2} molecule, which indicates that the electronic-vibrational qubits are worse than the ...

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The goal of this project is to improve energy efficiency of industrial crushing and grinding operations (comminution). Mathematical models of the comminution process are being used to study methods for optimizing the product size distribution, so that the amount of excessively fine material produced can be minimized. The goal is to save energy by reducing the amount of material that is ground below the target size, while simultaneously reducing the quantity of materials wasted as ''slimes'' that are too fine to be useful. This is being accomplished by mathematical modeling of the grinding circuits to determine how to correct this problem. The approaches taken included (1) Modeling of the circuit to determine process bottlenecks that restrict flowrates in one area while forcing other parts of the circuit to overgrind the material; (2) Modeling of hydrocyclones to determine the mechanisms responsible for retaining fine, ...

CERN Document Server

This paper focuses on the cross-layer issue of joint multiuser detection and resource allocation for energy efficiency in wireless CDMA networks. In particular, assuming that a linear multiuser detector is adopted in the uplink receiver, the case considered is that in which each terminal is allowed to vary its transmit power, spreading code, and uplink receiver in order to maximize its own utility, which is defined as the ratio of data throughput to transmit power. Resorting to a game-theoretic formulation, a non-cooperative game for utility maximization is formulated, and it is proved that a unique Nash equilibrium exists, which, under certain conditions, is also Pareto-optimal. Theoretical results concerning the relationship between the problems of SINR maximization and MSE minimization are given, and, resorting to the tools of large system analysis, a new distributed power control algorithm is implemented, based on very little prior ...

CERN Document Server

The Business Value of IT

Wastenet

as well as their use in optimizing the coating process .It will be shown how the differences

International Nuclear Information System (INIS)

The absorption, emission and magnetic circular dichroism spectra of the anionic complex (Cp_3Pr. NCS)"- were measured at room and low temperatures. On the basis of these spectra the electronic structure in the f-f range could be derived. The parameters of an empirical Hamiltonian were fitted to the experimentally determined crystal field splitting pattern. Compared with the previously examined neutral Cp_3 Pr.X complexes the quadratic crystal field parameter B_0"2 is considerably reduced.

CERN Document Server

In the inflationary scenario of loop quantum cosmology (LQC) in the presence of inverse-volume corrections, we give analytic formulas for the power spectra of scalar and tensor perturbations convenient to confront with observations. Since inverse-volume corrections can provide strong contributions to the running spectral indices, inclusion of terms higher than the second-order runnings in the power spectra is crucially important. Using the recent data of cosmic microwave background (CMB) and other cosmological experiments, we place bounds on the quantum corrections for a quadratic inflaton potential.

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The effect of the electric field on an exciton confined in a pair of vertically coupled quantum dots is studied. We use a single-band approximation and a parabolic model potential. As a result of these idealizations, we obtain a numerically solvable model, which is used to describe the influence of the electron-hole interaction on the Stark effect for the lowest-energy photoluminescence lines. We show that for intermediate tunnel coupling between the dots this interaction leads to an anomalous Stark effect with an essential deviation of the recombination energy from the usual quadratic dependence on the electric field.

Science.gov (United States)

... Accession Number : ADD321199. Title : OPTIMIZATION OF EDDY CURRENT PROBES FOR NDT OF CARBON FIBER COMPOSITES. ...

British Library Electronic Table of Contents (United Kingdom)

The broad use of Six Sigma in the improvement of all types of processes has provided new insight for how to design, analyze, and interpret formulation studies and mixture experiments. Experience has shown that, consistent with the Pareto principle, there are typically three to six key variables that have major effects on the performance of the process. Identifying these key variables increases your ability to control and optimize the process. Applying this concept to formulation studies suggests that we should be searching for those critical few components that are driving the performance of the product formulation. This thinking changes how we approach both the design and analysis phases of product formulation studies, including the reassessment of formulations in use today. A review of t...

British Library Electronic Table of Contents (United Kingdom)

The aim of this work is the development and experimental validation of a detailed dynamic fuel cell model using the gPROMS modeling environment. The model is oriented towards optimization and control and it relies on material and energy balances as well as electrochemical equations including semi-empirical equations. For the experimental validation of the model a fully automated and integrated hydrogen fuel cell testing unit was used. The predictive power of the model has been compared with the data obtained during load change experiments. A sensitivity analysis has been employed to reveal the most critical empirical model parameters that should be estimated using a systematic estimation procedure. Model predictions are in good agreement with experimental data under a wide range of operati...

British Library Electronic Table of Contents (United Kingdom)

A mathematical model for heat transfer during solidification in continuous casting of automobile steel, was established on researching under the influence of the solidifying process of bloom quality of CCM in the EAF steelmaking shop, at Shijiazhuang Iron and Steel Co. Ltd. Several steel grades were chosen to research, such as, 40Cr and 42CrMo. According to the results of the high temperature mechanical property tests of blooms, the respective temperature curves for controlling the solidification of different steels were acquired, and a simulating software was developed. The model was verified using two methods, which were bloom pinshooting and surface strand temperature measuring experiments. The model provided references for research on the solidifying process and optimization of a secon...

Energy Technology Data Exchange (ETDEWEB)

Adjustment of the rf phase in a linear accelerator is crucial for maintaining optimal performance. If phasing is incorrect, the beam will in general have an energy error and increased energy spread. While an energy error can be readily detected and corrected using position readings from beam position monitors at dispersion locations, this is not helpful for correcting energy spread in a system with many possible phase errors. Uncorrected energy spread results in poor capture efficiency in downstream accelerators, such as the Advanced Photon Source's (APS's) particle accumulator ring (PAR) or booster synchrotron. To address this issue, APS has implemented beam-to-rf phase detectors in the linac, along with software for automatic correction of phase errors. We discuss the design, implementation, and performance of these detectors and how they improved APS top-up operations.

British Library Electronic Table of Contents (United Kingdom)

Optimization of nonviral gene delivery typically focuses on the design of particulate carriers that are endowed with desirable membrane targeting, internalization, and endosomal escape properties. Topographical control of cell transfectability, however, remains a largely unexplored parameter. Emerging literature has highlighted the influence of cell-topography interactions on modulation of many cell phenotypes, including protein expression and cytoskeletal behaviors implicated in endocytosis. Using high-throughput screening of primary human dermal fibroblasts cultured on a combinatorial library of microscale topographies, we have demonstrated an improvement in nonviral transfection efficiency for cells cultured on dense micropit patterns compared to smooth substrates, as verified with flow...

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This research deals with in the study of the use of innovating magnetic sensors in eddy current non destructive inspection. The author reports an analysis survey of magnetic sensor performances. This survey enables the selection of magnetic sensor technologies used in non destructive inspection. He presents the state-of-the-art of eddy current probes exploiting the qualities of innovating magnetic sensors, and describes the methods enabling the use of these magnetic sensors in non destructive testing. Two main applications of innovating magnetic sensors are identified: the detection of very small defects by means of magneto-resistive sensors, and the detection of deep defects by means of giant magneto-impedances. Based on the use of modelling, optimization, signal processing tools, probes are manufactured for these both applications.

International Nuclear Information System (INIS)

One-dimensional core-shell polymer nanowires offer many advantages and great potential for many different applications. In this paper we introduce a highly versatile two-step template wetting process to fabricate two-component core-shell polymer nanowires with controllable shell thickness. PLLA and PMMA were chosen as model polymers to demonstrate the feasibility of this process. Solution wetting with different concentrations of polymer solutions was used to fabricate the shell layer and melt wetting was used to fill the shell with the core polymer. The shell thickness was analyzed as a function of the polymer solution concentration and viscosity, and the core-shell morphology was observed with TEM. This paper demonstrates the feasibility of fabricating polymer core-shell nanostructures using our two-step template wetting process and opens the arena for optimization and future experiments with polymers that are desirable for specific ...

Energy Technology Data Exchange (ETDEWEB)

The effect of asymmetry tilt angle ion implantation on polysilicon thin-film transistors (TFTs) device characteristics are investigated. This asymmetric source/drain (S/D) TFTs structure exhibits low leakage current and suppressed kink effect due to the relief of higher electric field near the drain junction side. It is shown that the optimal implantation tilt angle is 30 deg. in our annealing condition. And the anomalous off-state current is more than two orders of magnitude lower than that of the conventional TFTs. By well controlled the LDD region, this structure can act as a conventional structure in the on-state and the turn-on current will not be degraded. Besides, the device under severe hot carrier bias stress shows better hot carrier endurance.

Energy Technology Data Exchange (ETDEWEB)

This two-tomes book brings together the 108 presentations given at the first conference of the international institute of refrigeration (IIF/IIR) about air conditioning in high rise office buildings. The main themes are: general design and control systems, including split systems, radiant panels, fluctuating and gravity ventilation etc..; energy consumption, optimization and heat recovery; cold storage for peak shaving, including ice slurry circulation; indoor air quality; fire and smokes protection, protection against chimney effects and lighting spots; use of fuzzy logic and of neural networks. It includes also a description of the high rise building situation and works in progress in China, Japan and in some other countries. (J.S.)

Energy Technology Data Exchange (ETDEWEB)

Cold Heavy Oil Production with Sand (CHOPS) is an enhanced oil recovery method that induces sand production to form a network of wormholes that increase the porosity and permeability of a formation. Under proper conditions, CHOPS can improve formation flow characteristics. Integrated well completion strategies that were used to increase oil production at Fula oil field on the south flank of Mughad Basin in Sudan were described. Limited sand influx provided a means for effective sand control while eliminating the need for conventional sand control processes. Cold heavy oil production with limited sand influx requires optimized completion methods to stimulate sand production, thereby reducing oil flow resistance and prolonging the sand removal operation cycle. Completion tests were performed in terms of different formation conditions including perforating completion; perforating and full sand control ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes high speed rolling and gauge control in cold tandem mill for ultra-thin gauge strip at the Chiba Works of Kawasaki Steel Corporation. To improve the plate-out property of rolling oil, cationic polymeric coagulant was prepared. Rolling oil with cohesion independent of inorganic inclusions or phosphatide was developed, to improve the lubrication for cold rolling, remarkably. In addition, a low-cost Ti-enhanced work roll having high wear resistance and excellent grindability was developed. Rolling can be conducted at the optimal rolling roughness and operation can be performed at the highest rolling speed independent of the rolling treatment amount. Rolling speed at 2800 m/min was confirmed by developing the rolling oil with excellent lubrication and the work roll having high wear resistance. For the improvement of strip thickness accuracy at the steady state rolling, use of the backup roll as roller bearing was more effective ...

Energy Technology Data Exchange (ETDEWEB)

Study was made on the city bus driven by the series hybrid system composed of a small ceramic gas turbine (100kW), generator and lead storage battery. Two driving modes were adopted, 10-driving mode and real driving mode assuming a certain bus route in Tokyo. The motor is driven mainly by generated power and additionally by battery power, however, the engine/generator system is controlled at an optimum operation point (driving mode and regenerating mode) with a maximum thermal efficiency considering depth of discharge. Design voltage of the battery had nearly no effect on fuel consumption, while its capacity as large as possible was desirable unless its weight has an adverse effect on the system. The real driving mode was lower in fuel consumption by 39% than the 10-driving mode. Since real fuel consumption is largely affected by recovery rate of regenerable energy, the operation point of the motor should be optimized according to driving mode. ...

International Nuclear Information System (INIS)

This paper discusses the new quality assurance regulations of the Nuclear Regulatory Commission (NRC) for packaging and transportation of radioactive materials. These regulations became effective on October 18, 1977. Background information concerning these regulations and packaging and transportation history is included. The quality assurance program is described with indications of how it is composed of general (administrative) provisions which must meet the 18 quality assurance criteria and be approved by the NRC; specific provisions which appear in the DOT and NRC regulations and in the individual package design approval; and other specific procedures which are not required by regulations but which are necessary for the proper control of quality. The quality assurance program is to be developed using a graded approach for the application of pertinent criteria and optimizing the required degree of safety and control ...

Energy Technology Data Exchange (ETDEWEB)

For the expansion to 2.0 MTPY of the CVG Bauxilum alumina plant, the area of clarification and red mud washing was rearranged from four 2-thickener-5-washer trains to two 1-thickener-7-washer trains. As a result of this modification, the specific mud handling capacity of the existing tanks should be increased by almost 3-times. The time allowed for control actions was then significantly reduced, leading to the need of an on-line level detection system, in order to achieve a better and faster control of the operation. With this scope, it was developed and installed a new continuous mud level detector that gives the measurement of both mud and turbid zone levels in the tanks. The development of the new instrument started with an existing instrument for density measurements which was completely re-engineered in order to obtain the maximum readability in the densities founded along the full range of the tank height. Actually 28 tanks are equipped ...

Energy Technology Data Exchange (ETDEWEB)

In designing power system stabilizer (PSS), a major difficulty is to successfully treat the system`s uncertainties. These uncertainties arise because of changes in operating conditions, approximations in modeling, parameter variations caused by faults, etc. It is known that in the presence of uncertainties, conventional methodologies such as linear optimal technique, adaptive controls, etc., may fail to guarantee the stability of the system. On the other hand, the H{infinity} control theory provides potential ability to overcome this problem. However, some limitations still exist in the treatment of uncertainty. That is, the existing standard H{infinity}-PSSs cannot adequately treat the system uncertainties. Moreover, performance problems can arise in this approach due to the pole-zero cancellation phenomenon. To deal with the above mentioned limitations, a new design methodology for H{infinity}-PSS based on the ...

Energy Technology Data Exchange (ETDEWEB)

The demonstration test of a power system stabilizer, employing a fuzzy theory, in the two hydroelectric power stations of Kyusyu Electric Power Co., Inc. is described. The PSS inputs auxiliary signals to the automatic voltage regulator (AVR) of a generator and generates an electric torque in the direction opposite to the operating direction of a generator to enhance the damping effect and improve the system stability. Usually, the change in the slide information of a generator is detected, and the phase adjustment is performed so that the damping is the optimum value. However, since the damping is optimized in the specific system state, no complete damping may be obtained when the system state is changed. A fuzzy theory was thus applied for the control operation part. In a secondary fuzzy PSS, the velocity and acceleration were calculated from the slide information of a generator to produce a control signal. In the third ...

Science.gov (United States)

In the current wind turbine generation system, there are substantial problems such as the maximum power of the wind turbine cannot be obtained under the fluctuating wind speed, high in cost and low in annual net electricity production (due to mismatch between a generator and a wind turbine). A new wind turbine generator optimized for the wind turbine output is presented in order to solve such problems. This wind turbine generator consists of a permanent magnet generator, a reactor and a rectifier, and uses neither a control circuit which requires standby electricity nor a PWM converter having a switching element. By selecting most appropriate combination of the permanent magnet generator having multiple windings and the reactor connected in series with each winding, the maximum output of the wind turbine can be obtained without using a control circuit. The new wind turbine generator was directly coupled with the straight ...

Energy Technology Data Exchange (ETDEWEB)

Direct injection diesel engines power most of the heavy-duty vehicles. Due to their superior fuel economy, high power density and low carbon dioxide emissions, turbocharged, small bore, high speed, direct injection diesel engines are being considered to power light duty vehicles. Such vehicles have to meet stringent emission standards. However, it is difficult to meet these standards by modifying the in-cylinder thermodynamic and combustion processes to reduce engine-out emissions. After-treatment devices will be needed to achieve even lower emission targets required in the production engines to account for the anticipated deterioration after long periods of operation in the field. To reduce the size, mass and cost of the after-treatment devices, there is a need to reduce engine-out emissions and optimize both the engine and the aftertreatment devices as one integrated system. For example, the trade-off between engine-out NOx and PM, suggests that one of these ...

Science.gov (United States)

The brain hypothermia treatment is an attractive therapy for the neurologist because of its neuroprotection in hypoxic-ischemic encephalopathy patients. The present paper deals with the possibility of controlling the brain and other viscera in different temperatures from the viewpoint of system control. It is theoretically attempted to realize the special brain hypothermia treatment to cool only the head but to warm the body by using the simple apparatus such as the cooling cap, muffler and warming blanket. For this purpose, a biothermal system concerning the temperature difference between the brain and the other thoracico-abdominal viscus is synthesized from the biothermal model of hypothermic patient. The output controllability and the asymptotic stability of the system are examined on the basis of its structure. Then, the maximum temperature difference to be realized is shown dependent on the temperature range of the ...

Energy Technology Data Exchange (ETDEWEB)

Reaction Engineering International (REI) has established a project team of experts to develop a technology for combustion systems which will minimize NO x emissions and minimize carbon in the fly ash. This much need technology will allow users to meet environmental compliance and produce a saleable by-product. This study is concerned with the NO x control technology of choice for pulverized coal fired boilers, ?in-furnace NO x control,? which includes: staged low-NO x burners, reburning, selective non-catalytic reduction (SNCR) and hybrid approaches (e.g., reburning with SNCR). The program has two primary objectives: 1) To improve the performance of ?in-furnace? NO x control processes. 2) To devise new, or improve existing, approaches for maximum ?in-furnace? NO x control and minimum unburned carbon. The program involves: 1) fundamental studies at laboratory- and bench-scale to define NO reduction ...

DEFF Research Database (Denmark)

This thesis - Resource Management in Broadband Communication Networks - deals with different ways of optimizing the available resources of data- or telecommunication networks. Especially topics like optimal routing, load balancing and fast recovery of routes in case of link failures are covered. The first part gives a brief description of some of the existing protocols for routing and controlling resources, such as RSVP, OSPF, BGP, PNNI, etc. The remaining part concerns the following two fundamentally different approaches to resource management etc.: - Software agents - Simulated ants In the beginning of the part concerning software agents a description of what exactly constitutes software agents, according to the scientists and according to the organization, FIPA is given. After this, the main results from the IMPACT project are presented. The IMPACT project is an EU-project that aimed at developing a demonstration ...

International Nuclear Information System (INIS)

We prove rigorously that the structure constants of the leading (highest spin) linear terms in the commutation relations of the conformal chiral operator algebra W_#infinity# are identical to those of the Diff_0"+ R"2 algebra generated by area preserving diffeomorphisms of the plane. Moreover, all quadratic terms of the W_N algebra are found to be absent in the limit N#->##infinity#. In particular we show that W_#infinity# is a central extension of Diff_0"+ R"2 with non-trivial cocycles appearing only in the commutation relations of its Virasoro subalgebra. We also propose a representation of W_#infinity# in terms of a single scalar field in 2+1 dimensions and discuss its significance in the context of quantum field theory. (orig.).

International Nuclear Information System (INIS)

The electrical resistivity, Hall effect, and magnetic susceptibility of single-crystal UPd_2Si_2 have been studied between 4.2 and 300 K. A large anisotropy was observed in both the magnetic and transport properties. There is a quadratic temperature dependence of the resistivity for a range of temperatures between 4.2 and 80 K. At higher temperatures, the resistivity indicates a Kondo-type behavior. The behavior of these quantities is accounted for by the magnetic phase transitions at 108 and 136 K reported from neutron-scattering studies. At high temperatures, the magnetic susceptibility of UPd_2Si_2 is Curie-Wiess-like along the c axis. The temperature dependence of the Hall coefficient above 108 K is accounted for by a theoretical model invoking skew scattering of conduction electrons by localized magnetic moments.

CERN Document Server

A generalized relativistic harmonic oscillator for spin 1/2 particles is studied. The Dirac Hamiltonian contains a scalar, $S$, and a vector, $V$, quadratic potentials in the radial coordinate, as well as a tensor potential, $U$, linear in $r$. Setting either or both combinations $\\Sigma=S+V$ and $% \\Delta=V-S$ to zero, analytical solutions for bound states of the corresponding Dirac equations are found. The eigenenergies and wave functions are presented and particular cases are discussed, devoting a special attention to the non-relativistic limit and the case $\\Sigma=0$, for which pseudospin symmetry is exact. We also show that the case $U=\\Delta=0$ is the most natural generalization of the non-relativistic harmonic oscillator. The radial node structure of the Dirac spinor is studied for several combinations of harmonic oscillator potentials, and that study allows us to explain why nuclear intruder levels cannot be described in the framework of the ...

British Library Electronic Table of Contents (United Kingdom)

There are two difficulties encountered in modeling valveless micropumps using lumped-element methods. The pressure loss coefficient for fluidic diodes used in valveless pumps to rectify flow depends on the flow direction. A problem arises in choosing the proper loss correlation because the flow direction is not known a priori. Another problem is the quadratic form of the equation for the flow through the fluidic diodes, which brings about multiple solutions. The above problems become even more serious in multi-chamber cases. They are overcome in this study by suitably formulating the flow resistance. In addition, the flow inertia is accounted for in the unsteady model. The steady and unsteady models are evaluated by comparing with CFD simulations, which also serve to illustrate the flow fi...

British Library Electronic Table of Contents (United Kingdom)

According to the environmental Kuznets curve hypothesis, the relationship between per-capita GDP and per-capita pollutant emissions has an inverted-U shape. This implies that, past a certain point, economic growth may actually be profitable for environmental quality. Most studies on this subject are based on estimating fully parametric quadratic or cubic regression models. While this is not technically wrong, such an approach somewhat lacks flexibility since it may fail to detect the true shape of the relationship if it happens not to be of the specified form. We use semiparametric and flexible nonlinear parametric modeling methods in an attempt to provide more robust inferences. We find little evidence in favour of the environmental Kuznets curve hypothesis. Our main results could be inte...

British Library Electronic Table of Contents (United Kingdom)

Product-sum property states that an ordered pair (s"n,p"n) is unique for any ordered set a"1,a"2,...,a"n where a"i,n@?N, and s"n and p"n are the sum and product of the elements of the set, respectively. This fact has been exploited to develop an O(log(M)) time complexity algorithm for pattern searching in a large dataset, where M is the number of records in the dataset. Two potential applications (from databases and computational biology) of this property have been demonstrated to show the effectiveness and working of the proposed algorithm. The space complexity of the algorithm rises to the quadratic order.

CERN Document Server

A set of mode-coupled excitation equations for the slowly-growing amplitudes of dielectric waveguide eigenmodes is derived as a description of the electromagnetic signal field of a high-gain free-electron laser, or FEL, including the effects of longitudinal space-charge. This approach to describing the field basis set has notable advantages for FEL analysis in providing an efficient characterization of such eigenmodes, and in allowing a clear connection to free-space propagation of the input (seeding) and output radiation. A simple transformation converts the coupled differential excitation equations into a set of coupled algebraic equations and yields a matrix determinant equation for the FEL eigenmodes. A quadratic index medium is used as a model dielectric waveguide to obtain an expression for the predicted spot size of the dominant eigenmode, in the approximation that it consists of a single gaussian mode.

UK PubMed Central (United Kingdom)

BackgroundPrior research links optimism to physical health, but the strength of the association has not been systematically evaluated.PurposeFull Text Available

Science.gov (United States)

Sep 18, 2009 ... It is proposed to develop desensitized optimal filtering ... in robust and/or adaptive generalized Kalman and Sigma-Point filters for ...

International Science & Technology Center (ISTC)

Development of Frequency Controlled Electric Drives

Energy Technology Data Exchange (ETDEWEB)

The challenge for truck engine product engineering is not only to fulfill increasingly stringent emission requirements, but also to improve the engine's economical viability in its role as the backbone of our global economy. While societal impact and therefore emission limit values are to be reduced in big steps, continuous improvement is not enough but technological quantum leaps are necessary. The introduction and refinement of electronic control of all major engine systems has already been a quantum leap forward. Maximizing the benefits of these technologies to customers and society requires full use of parameter optimization and other enabling technologies. The next big step forward will be widespread use of exhaust aftertreatment on all transportation related diesel engines. While exhaust gas aftertreatment has been successfully established on gasoline (Otto cycle) engines, the introduction of exhaust aftertreatment especially for ...

Energy Technology Data Exchange (ETDEWEB)

For an air conditioned building, the major electricity consumption is by the heating, and air conditioning (HVAC) system. As energy saving strategies may be in conflict with the criteria of indoor air quality and thermal comfort, a concept of the building environmental performance model (BEPM) has been developed to optimize energy consumption in HVAC systems without any deterioration of the indoor air quality and thermal comfort. The BEPM is divided into two main modules: the adaptive comfort temperature (ACT) module and the new demand control ventilation (nDCV) module. This study aims to enhance and prompt the conventional operation of the air side systems by incorporating temperature reset with the adaptive comfort temperature control and the new demand control ventilation system in high rise buildings in Hong Kong. A new example weather year (1991) was established as a reference to compute the energy ...

International Nuclear Information System (INIS)

The effects of extended source-to-surface distance (SSD) on the electron beam dose profiles were evaluated for various electron beam energies - 6, 9, 12, 15 and 20 MeV - and the accuracy of various output correction methods was analysed on a Mitsubishi linear accelerator using a radiation field analyser (RFA). The dose fall-off region of the central axis depth-dose curves was nearly independent for SSDs up to 120 cm where as in the build-up region, a marginal reduction of surface dose was observed, particularly for lower energies and for smaller field sizes. Effective SSDs and virtual source distances were evaluated for field sizes ranging from 5x5 to 15x15 cm"2 for various energies. Curve fitting was done with the measured outputs with various equations and coefficients were evaluated. The accuracy of the derived output correction factors by effective SSD, virtual source distance and curve-fit methods was assessed by evaluating correlation coefficients between the calculated and the ...

Science.gov (United States)

Current dewatering methods for ultra-fine coal suspensions are inadequate and usually require subsequent expensive thermal drying. This unique dewatering method is based on pressurized electroosmosis, the movement of water by an electrical field through a porous medium, under modest pressure, e.g., 110 psi. More ultra-fine coal can be utilized since an effective dewatering process can be realized by combining known filtration techniques with electroosmosis. The dewatering efficiency can be significantly improved, the residual moisture of the cake can be substantially reduced and handling problems can be eliminated. Bench-scale testing is being used to optimize the parameters which influence pressurized electroosmotic dewatering (PED) of ultra-fine coal suspensions. Particle size distribution is being addressed to obtain a maximum density for a given pressure such that pore saturation is maintained allowing electroosmosis to be effective for a longer period. The ...

KoreaScience (Korea)

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International Nuclear Information System (INIS)

An irradiation head with sample holders is described and measurement geometry is reported. Measurements were made for optimizing the distance between the source and the sample and for optimizing the sample diameter. The optimal distance between the source and the sample does not depend on the collimator diameter. The sample diameter should not exceed 30 - 35 mm. Sensitivity and detection limits were determined for Zn, Pb and Br and calibration curves were plotted. (M.D.) 6 figs., 2 tabs., 4 refs.

DEFF Research Database (Denmark)

Udgivelsesdato: MAR

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

KoreaScience (Korea)

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KoreaScience (Korea)

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KoreaScience (Korea)

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Science.gov (United States)

... Note that the terminal ... Probability and Statistics with Reliability, Queueing, and Computer ... Weiss, G., "Stochastic Bounds on Distributions of Optimal ...

CERN Document Server

Nature-inspired algorithms are among the most powerful algorithms for optimization. This paper intends to provide a detailed description of a new Firefly Algorithm (FA) for multimodal optimization applications. We will compare the proposed firefly algorithm with other metaheuristic algorithms such as particle swarm optimization (PSO). Simulations and results indicate that the proposed firefly algorithm is superior to existing metaheuristic algorithms. Finally we will discuss its applications and implications for further research.

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

An automated Time Resolved Aerosol Collector (TRAC) has been developed for sequential sampling of field-collected aerosols for laboratory-based Computer Controlled Scanning Electron Microscopy/Energy Dispersed X-ray (CCSEM/EDX) single particle analysis. The collector is optimized for use of grid-supported 20 nm carbon films as deposition substrates. The carbon films have low enough X-ray background to permit EDX analysis down to 0.1-0.2 ?m particles, including detection of low-Z elements: C, N, & O. The TRAC provides unattended sampling onto a set of 151 individual grids, at sequential time intervals as short as 1 min. After collection, the samples are sealed and refrigerated pending analysis. The utility of the TRAC-CCSEM/EDX approach is exemplified using the aerosol samples collected during the Texas 2000 Air Quality Studies (Aug. 15 ? Sept. 15, 2000). We are able to quantitatively follow the time evolution in the relative contribution of ...

Energy Technology Data Exchange (ETDEWEB)

Accurate engineering cost estimates are critical in developing bids for new work, and for effective resource allocation and project control. This study reports on design estimating methods found in the literature, and on the results of two empirical studies of how estimating techniques are used in professional practice and their accuracy. The study found great reliance on a classic {open_quotes}activity analysis{close_quotes} approach to estimating design resources, and significant hazards in commonly used parametric techniques. The study found that project managers expect their estimates to be accurate (with 80% confidence interval) of between -10% to +25%. The study also found that actual bids between engineering firms had a much greater range (-40% to +45%) than can be explained by accuracy. Perhaps most importantly the study found that none of the sampled design firms used probabilistic techniques to optimize their project bids or to manage ...

Science.gov (United States)

Because hydrogenation of coal to liquid products (oils) is accompanied by distributions of complex by-product mixtures (IOM, preasphaltenes, asphaltenes and gases) which change as a function of reaction variables (time, temperature and pressure) and reactor configuration, the determination of selectivity relationships for coal liquefaction catalysts has been a difficult and time-consuming task involving numerous experiments to adequately describe catalyst performance over a range of conditions. This paper describes a method for analyzing the experimental results of coal liquefaction reactions which may be applied to a number of aspects of coal liquefaction research and process control, including: rapid selectivity and performance screening for catalysts; correlation of laboratory results with process parameters; and optimization of product yield for plant process conditions. Catalyst selectivity and performance screening will be emphasized ...

Science.gov (United States)

The purpose of this project was to design, build, and characterize the performance of a volume breast ultrasound (VBUS) scanner that images the pendant breast. VBUS scanner design includes a: 1) clinical ultrasound scanner and transducer; 2) scanning table with a hole for the pendant breast; 3) rotational gantry; 4) probe mounting assembly; 5) compressionless breast stabilization device; 6) acquisition, control, reconstruction, and display software. Performance assessment characterized a variety of parameters including: spatial resolution, uniformity, and distortion using high and low contrast test objects in both horizontal and vertical scanning modes. The VBUS scanner modules have been constructed and initial performance evaluated. Approximately 300 scans are acquired over 360 degrees in 18 seconds. Reconstruction requires 25 ms per slice. Test object images depicted hyper- and hypo-echoic masses and demonstrated good resolution, soft tissue contrast and reduced ...

International Nuclear Information System (INIS)

The admissibility of nuclear forensics measurements and opinions derived from them in US Federal and State courts are based on criteria established by the US Supreme Court in the case of Daubert v. Merrell Dow and the 2000 Amendment of Rule 702 of the Federal Rules of Evidence. These criteria are being addressed by new efforts that include the development of certified reference materials (CRMs) to provide the basis for analytical method development, optimization, calibration, validation, quality control, testing, readiness, and declaration of measurement uncertainties. Quality data is crucial for all stages of the program, from R and D, and database development, to actual casework. Weakness at any point in the program can propagate to reduce the confidence of final conclusions. The new certified reference materials will provide the necessary means to demonstrate a high level of metrological rigor for nuclear forensics evidence and will form a ...

Energy Technology Data Exchange (ETDEWEB)

A system and method for generating global asynchronous signals in a computing structure. Particularly, a global interrupt and barrier network is implemented that implements logic for generating global interrupt and barrier signals for controlling global asynchronous operations performed by processing elements at selected processing nodes of a computing structure in accordance with a processing algorithm; and includes the physical interconnecting of the processing nodes for communicating the global interrupt and barrier signals to the elements via low-latency paths. The global asynchronous signals respectively initiate interrupt and barrier operations at the processing nodes at times selected for optimizing performance of the processing algorithms. In one embodiment, the global interrupt and barrier network is implemented in a scalable, massively parallel supercomputing device structure comprising a plurality of processing nodes interconnected ...

Energy Technology Data Exchange (ETDEWEB)

Since 1994-95 the University of Applied Sciences Berne is working on weather-proof electric bicycles. The main drawbacks of bicycles, no weather-protection, little comfort of the saddle, the difficulty of climbing hills, are to be eliminated. The electro-mechanical drive-train of 'Ultraleichtmobil ULM BE 2000', developed in 1995-96, was mechanically complicated. This resulted in reduced energy-efficiency and intense maintenance. Too, the drive-train was expensive in production. A fully electrical human-power transmission seemed to be the solution to the problems mentioned above. It is appealing not only to the user of the vehicle, but also to the producer and to the persons doing the maintenance. Following an internal study showing the technical feasibility of such an electrical transmission, a controllable DC/DC-converter which allows to operate a pedal-driven generator at maximum efficiency has been developed. The electrical transmission is the ...

Science.gov (United States)

A strategic partnership was formed among the American Foundrymen`s Society and the Federal government to develop and transfer the technology needed by the US foundry industry to: increase energy efficiency of cupola melting; improve recovery of carbon, silicon, and manganese through reduced oxidation losses; and improve productivity due to more uniform and predictable iron compositions. An effective mathematical model of the cupola offers a solution to the complex and interactive chemical and heat transfer processes to melt cast iron. The transient changes in charge size, charge composition, blast rate, and coke rate are used to optimize operation to improve melting rates, minimize oxidation losses of valuable alloying elements (C, Si, and Mn), and maintain iron composition. Despite these challenges, the cupola produces iron at a lower cost, and have better environmental controls than other melting process with 70% of domestic liquid iron ...

Energy Technology Data Exchange (ETDEWEB)

This report surveys the possibilities and restrictions of different construction materials for the purpose of the blades of a small stall regulated turbine. For example scaling up, material saving at decreasing of static or dynamic loads, comparisons of global costs based on prices per unit of weight, etc. For the mutual comparison of construction materials for turbine blades the starting point is a stall regulated horizontal axis turbine with a rotor diameter of 16 m and a tipvane speed of about 64 m/s. Short descriptions are given of the materials and of the applied production methods with the resulting blade geometry. The blade skins are dimensionized for storm loads after the optimalization of the blade geometry, needed for the design wind speed, is recorded. The resulting blade skins are mutually compared as for weight, mass inertia and bending stiffness. Also a comparison took place of the resulting reserve factors against load variations caused by gusts of ...

Energy Technology Data Exchange (ETDEWEB)

During this project we experimentally evaluated the below-ground biomass and carbon allocation and partitioning of four different fast- and slow-growing families of loblolly pine located in Scotland County, NC, in an effort to increase the long-term performance of the crop. The trees were subjected to optimal nutrition and control since planting in 1993. Destructive harvests in 1998 and 2000 were used for whole?plant biomass estimates and to identify possible family differences in carbon acquisition (photosynthesis) and water use efficiency. At regular intervals throughout each year we sampled tissues for carbohydrate analyses to assess differences in whole-tree carbon storage. Mini rhizotron observation tubes were installed to monitor root system production and turnover. Stable isotope analysis was used to examine possible functional differences in water and nutrient acquisition of root systems between the various families. A genetic ...

Energy Technology Data Exchange (ETDEWEB)

Anaerobic treatment of olive oil mill wastewaters (COD up to 220 kg/cubic m) is feasible, and the most promising results were obtained on UASB reactors, both at laboratory and pilot scale (tank capacity 15 litres and 5 cubic m), fed on diluted waste (COD = 13-18 kg/cubic m). Volumetric loading rates ranging from 16-21.5 kg COD/cubic m/day and 70% removal efficiencies were obtained with these digesters. Start-up of UASB reactors fed on olive oil mill waste is a delicate step which still has to be fully controlled and optimized. The best results were obtained by starting with very diluted waste (COD = 5 kg/cubic m). Granulation of the sludge, as achieved in Dutch UASB digesters fed on sugar beet wastewaters, was not obtained, but, even so, the settleability of the sludge was very good. 22 references.

Energy Technology Data Exchange (ETDEWEB)

An optimization of fuel bundle geometry using the subchannel code ASSERT is performed in support of Candu fuel design to enhance the thermohydraulics performance. The new bundle design is based on a reference CANFLEX bundle with changes to the centre and inner-ring element diameters and pitch-circle diameters (PCDs) of various element rings. Different methods of varying the PCDs for reaching the optimized geometry are considered in an attempt to minimize the optimization effort. The optimized geometry in the present analysis is the one that maximizes the dryout power and that has simultaneous CHF (critical heat flux) initiation involving more than one subchannel rings. (authors)

Science.gov (United States)

The Defense Advanced Research Projects Agency (DARPA) inaugurated a program addressing research and development for an Exoskeleton for Human Performance Augmentation in FY!2001. A team consisting of Oak Ridge National Laboratory, the prime contractor, AeroVironment, Inc., the Army Research Laboratory, the University of Minnesota, and the Virginia Polytechnic Institute has recently completed an 18-month Phase I effort in support of this DARPA program. The Phase I effort focused on the development and proof-of-concept demonstrations for key enabling technologies, laying the foundation for subsequently building and demonstrating a prototype exoskeleton. The overall approach was driven by the need to optimize energy efficiency while providing a system that augmented the operator in as transparent manner as possible (non-impeding). These needs led to the evolution of two key distinguishing features of this team's approach. The first is the ...

Energy Technology Data Exchange (ETDEWEB)

The training of a new project team member was completed (Task 2.1). The Software Requirements Document was written (Task 2.3). It was determined that the CAPE-OPEN interfaces are sufficient for the communication between Fluent and V21 Controller (Task 2.4). The AspenPlus-Fluent prototype on allyl/triacetone alcohol production was further developed to assist the GUI and software design tasks. The prototype was also used to analyze the sensitivity of a process simulation result with respect to a parameter in a CFD model embedded in the process simulation. Thus the integration of process simulation and CFD provides additional process insights and enables the engineer to optimize overall process performance (e.g., product purity and yield) with respect to important CFD design and operation parameters (e.g., CSTR shaft speed). A top-level design of the V21 Controller was developed and discussed. A draft version of the Software ...

International Nuclear Information System (INIS)

The first Advanced Boiling Water Reactor (ABWR) started commercial operation as Tokyo Electric Power Company's (TEPCO) Kashiwazaki-Kariwa Nuclear Power Station Unit No.6 (K-6) in November 1996 and its sister Unit No.7 (K-7) in July 1997. The ABWR was developed to achieve higher reliability and safety margin while improving overall operability and economics. To achieve these goals, the optimal Boiling Water Reactor (BWR) technologies had been studied, tested and were finally adopted into the ABWR design. These technologies were called 'First of a Kind' and include the Reactor Internal Pump (RIP), Fine Motion Control Rod Drive (FMCRD), Reinforced Concrete Containment Vessel (RCCV), and integrated digital Instrumentation and Control System (I and C). Intensive development study, confirmation tests and verification tests were conducted by the plant equipment suppliers, electric utilities, and government agencies. During plant ...

Energy Technology Data Exchange (ETDEWEB)

A bottom-up approach is used here to combine carbon nanotubes synthesized by CVD and organically capped platinum nanoparticles electrocatalyst exhibiting a direct electrochemical activity towards oxygen reduction. Both nano-objects are handled in liquid suspension and are associated together in a controlled way. The nanocomposite liquid dispersions can be precisely controlled in terms of platinum nanoparticles to carbon nanotubes weight ratios (NP/NT) which correspond to different coverages of nanotubes by nanoparticles. Electrodes with low to ultra-low platinum loadings can then be prepared on porous fuel cell carbon supports by filtration. The direct electrochemical activity towards aqueous oxygen reduction reaction (ORR) of electrodes with platinum loadings ranging from about 1 to 60 {mu}g/cm{sup 2} is reported without any activation step in order to keep the features of the nanoparticles intact. Before that, we studied the responses ...

Energy Technology Data Exchange (ETDEWEB)

The needs of large industrial, commercial, and institutional energy consumers are more closely connected with the needs of power utilities and energy services companies, a result of the evolving global energy environment. Consumer choice, competition amongst energy suppliers, and increased demand are brought about in some regions by deregulation. Increasingly, large energy consumers expect high levels of quality and reliability from the energy delivered. As a result, management of the cost and the quality of the energy product and the energy assets that produce, deliver, control and consume it requires different strategies. Three major challenges must be overcome: (1) requirement to support economic and efficient delivery, purchasing and use of energy, (2) requirement to guarantee higher levels of power quality and reliability, and (3) requirement to supply the growing demand for energy while establishing a market-based pricing system. The solution is the ...

International Nuclear Information System (INIS)

... v. 15(10) p. 445-449. automation control equipment fluid flow fluidic control

Science.gov (United States)

Title list.

International Nuclear Information System (INIS)

The commutators of standard Virasoro generators and fields generate various representations of the centreless Virasoro algebra depending on a conformal dimension J of the field in question (J is related to the Bargmann index of SU(1,1) generated by L_m, m=0,#+-#1). We introduce the notion of q-conformal dimension for various oscillator realizations of q-deformed Virasoro (super)algebras proposed earlier. We use the field theoretical approach introduced recently in which the q-Virasoro currents L"#alpha# (z) are expressed as Schwinger-like point-split normally ordered quadratic expressions in elementary fields. We extend this approach and probe the elementary fields A(z) (the q-superstring coordinate, momentum and fermionic field) and their powers by the q-Virasoro generators L"#alpha#_m (i.e. we calculate the commutators [L"#alpha#_m,A(z)]) and show that to all of them can be assigned just the standard non-deformed conformal dimension. (orig.).

Energy Technology Data Exchange (ETDEWEB)

We consider spatially homogeneous (but generally non-isotropic) cosmologies in the recently proposed Horava-Lifshitz gravity and compare them to those of general relativity using Hamiltonian methods. In all cases, the problem is described by an effective point particle moving in a potential well with exponentially steep walls. Focusing on the closed-space cosmological model (Bianchi type IX), the mixmaster dynamics is now completely dominated by the quadratic Cotton tensor potential term for a very small volume of the universe. Unlike general relativity, where the evolution toward the initial singularity always exhibits chaotic behavior with alternating Kasner epochs, the anisotropic universe in Horava-Lifshitz gravity (with parameter lambda > 1/3) is described by a particle moving in a frozen potential well with fixed (but arbitrary) energy E. Alternating Kasner epochs still provide a good description of the early universe for very large E, but the ...

CERN Document Server

The structure of Poisson polynomial algebras of the type obtained as semiclassical limits of quantized coordinate rings is investigated. Sufficient conditions for a rational Poisson action of a torus on such an algebra to leave only finitely many Poisson prime ideals invariant are obtained. Combined with previous work of the first-named author, this establishes the Poisson Dixmier-Moeglin equivalence for large classes of Poisson polynomial rings, such as semiclassical limits of quantum matrices, quantum symplectic and euclidean spaces, quantum symmetric and antisymmetric matrices. For a similarly large class of Poisson polynomial rings, it is proved that the quotient field of the algebra (respectively, of any Poisson prime factor ring) is a rational function field $F(x_1,...,x_n)$ over the base field (respectively, over an extension field of the base field) with $\\{x_i,x_j\\}= \\lambda_{ij} x_ix_j$ for suitable scalars $\\lambda_{ij}$, thus establishing a ...

International Nuclear Information System (INIS)

The advances in laser technology have made available very short and intense laser pulses which can be used to seed a high-gain single-pass free-electron laser (FEL) amplifier. With these seed pulses, a regime of the FEL interaction where the radiation evolution is simultaneously dominated by nonlinear effects (saturation) and time-dependent effects (slippage) can be explored. This regime is characterized by the propagation of a solitary wavelike pulse where the power of the optical wave grows quadratically with time, its pulse length decreases and the spectral bandwidth increases. We analyze the interplay between the field and particle dynamics of this propagation regime which was studied before and termed super-radiance. Furthermore we analyze the properties of the strong higher-order harmonic emission from this wave and its behavior when propagating in a cascade FEL. The super-radiant pulse is indeed capable of passing through the stages of a cascade FEL and to ...

CERN Document Server

This paper presents and implements an iterative feedback design algorithm for stabilisation of discrete-time switched systems under arbitrary switching regimes. The algorithm seeks state feedback gains so that the closed-loop switching system admits a common quadratic Lyapunov function (CQLF) and hence is uniformly globally exponentially stable. Although the feedback design problem considered can be solved directly via linear matrix inequalities (LMIs), direct application of LMIs for feedback design does not provide information on closed-loop system structure. In contrast, the feedback matrices computed by the proposed algorithm assign closed-loop structure approximating that required to satisfy Lie-algebraic conditions that guarantee existence of a CQLF. The main contribution of the paper is to provide, for single-input systems, a numerical implementation of the algorithm based on iterative approximate common eigenvector assignment, and to establish cases where ...

Energy Technology Data Exchange (ETDEWEB)

The Environmental Kuznets Curve (EKC) hypothesis states that pollution levels increase as a country develops, but begin to decrease as rising incomes pass beyond a turning point. In EKC analyses, the relationship between environmental degradation and income is usually expressed as a quadratic function with the turning point occurring at a maximum pollution level. Other explanatory variables have been included in these models, but income regularly has had the most significant effect on indicators of environmental quality. One variable consistently omitted in these relationships is the price of energy. This paper analyzes previous models to illustrate the importance of prices in these models and then includes prices in an econometric EKC framework testing energy/income and CO{sub 2}/income relationships. These long-run price/income models find that income is no longer the most relevant indicator of environmental quality or energy demand. Indeed, we find no ...

Energy Technology Data Exchange (ETDEWEB)

California utilities have been exploring the use of critical peak prices (CPP) to help reduce needle peaks in customer end-use loads. CPP is a form of price-responsive demand response (DR). Recent experience has shown that customers have limited knowledge of how to operate their facilities in order to reduce their electricity costs under CPP (Quantum 2004). While the lack of knowledge about how to develop and implement DR control strategies is a barrier to participation in DR programs like CPP, another barrier is the lack of automation of DR systems. During 2003 and 2004, the PIER Demand Response Research Center (DRRC) conducted a series of tests of fully automated electric demand response (Auto-DR) at 18 facilities. Overall, the average of the site-specific average coincident demand reductions was 8% from a variety of building types and facilities. Many electricity customers have suggested that automation will help them institutionalize their electric demand ...

UK PubMed Central (United Kingdom)

The brain maintains internal models of its environment to interpret sensory inputs and prepare actions. While behavioral studies demonstrated that these internal models are optimally adapted...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe aim of this study was to compare and to validate different dose calculation algorithms for the use in radiation therapy of small lung lesions and to optimize the treatment...Full Text Available

UK PubMed Central (United Kingdom)

Operation of an X-ray spectrometer based on a spherical variable-line-spacing (VLS) grating is analyzed using dedicated ray-tracing software allowing fast optimization of the grating parameters and...Full Text Available

CERN Document Server

A dissipative particle swarm optimization is developed according to the self-organization of dissipative structure. The negative entropy is introduced to construct an opening dissipative system that is far-from-equilibrium so as to driving the irreversible evolution process with better fitness. The testing of two multimodal functions indicates it improves the performance effectively

UK PubMed Central (United Kingdom)

The conventional IMRT planning process involves two stages in which the first stage consists of fast but approximate idealized pencil beam dose calculations and dose optimization and the second...Full Text Available

International Nuclear Information System (INIS)

This study describes the formulations to optimize the time interval of inspections and/or replacements of equipment/parts taking into account the probability density functions (PDF) for failure rates and parameters of failure distribution functions (FDF) and evaluates the optimized results of these time intervals using our formulations by comparing with those using only representative values of failure rates and the parameters of FDF instead of using these PDFs. The PDFs are obtained with Bayesian method and the representative values are obtained with likelihood estimation method. However, any significant difference is not observed between both optimized results within our preliminary calculations. (author)

Energy Technology Data Exchange (ETDEWEB)

This paper presents a new algorithm for the optimal long-range generation planning for a thermal system with pumped-storage plants. The algorithm is based upon the analytical production costing model developed under the assumption of Gaussian probabilistic distribution of random load fluctuations and plant outages. The optimization problem consists of the master problem to determine the annual investment, and the pumped-storage subproblem to determine the optimal pumped-storage operation. The master problem is formulated as a Hamiltonian minimization problem, and the pumped-storage subproblem is solved using the concept of peak-shaving operation on the original load curve.

KoreaScience (Korea)

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Science.gov (United States)

... 1]. Results and Discussion A cross section of liquid feed direct borohydride fuel cell model was created and studied. The ...

Science.gov (United States)

... populations ..... 63 34 Vertebral ultimate compressive strength for various populations ..... 64 35 ...

Science.gov (United States)

... In this paper research aimed at creating a computer vision system to power such an optimal edging and ... ...

Energy Technology Data Exchange (ETDEWEB)

An optimization criterion accounting for the energy and material consumption is defined. The allowed limits of the variations in the technological factors are discussed and the optimization criterion values within these limits are calculated. The analysis presented, demonstrating the significance of the chosen factors for the production cost-price, is of great practical importance. (orig.).

Energy Technology Data Exchange (ETDEWEB)

In this paper, a new design methodology for determining the size, location, type and number of capacitors to be placed on a radial distribution system is presented. The objective is to minimize the peak power losses and the energy losses in the distribution system considering the capacitor cost. A sensitivity analysis based method is used to select the candidate locations for the capacitors. A new optimization method using a Genetic Algorithm is proposed to determine the optimal selection of capacitors. Test results have been presented along with the discussion of the algorithm.

CERN Document Server

We obtain a simple derivation of the optimal quantum state estimation of a two-level system using the no-signaling principle. In particular, we show that the no-signaling principle determines the unique form of the guessing probability, independently to a given figure of merit such as the fidelity or the information gain. This proves that optimal measurements for a two-level quantum system is the same for almost all figures of merit.

CERN Document Server

Nature-inspired algorithms such as Particle Swarm Optimization and Firefly Algorithm are among the most powerful algorithms for optimization. In this paper, we intend to formulate a new metaheuristic algorithm by combining Levy flights with the search strategy via the Firefly Algorithm. Numerical studies and results suggest that the proposed Levy-flight firefly algorithm is superior to existing metaheuristic algorithms. Finally implications for further research and wider applications will be discussed.

KoreaScience (Korea)

Full Text Available

CERN Document Server

Randomized Algorithms for Analysis and Control of Uncertain Systems

International Nuclear Information System (INIS)

... bwr type reactors closures fluidic control devices operation performance pwr

Science.gov (United States)

It is shown that, although accelerometer control systems are not well-posed in the sense of Salamon,

International Science & Technology Center (ISTC)

Commercial Production and Development, in Entomopathogenic Nematodes in Biological Control

CERN Document Server

Control of Phosphorus Transient Enhanced Diffusion using Co-implantation

Science.gov (United States)

This article describes a methodology that implements a Markov decision process (MDP) optimization technique in a real time fed-batch experiment. Biological systems can be better modeled under the stochastic framework and MDP is shown to be a suitable technique for their optimization. A nonlinear input/output model is used to calculate the probability transitions. All elements of the MDP are identified according to physical parameters. Finally, this study compares the results obtained when optimizing ethanol production using the infinite horizon problem, with total expected discount policy, to previous experimental results aimed at optimizing ethanol production using a recombinant Escherichia coli fed-batch cultivation. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 55: 317-327, 1997. PMID:18636490