Sample records for voltage-mode control methods

  1. A Comparative Study of Analog Voltage-mode Control Methods for Ultra-Fast Tracking Power Supplies

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.


    gain, leading to superior output impedance performance in the UFTPS application; this is explained using a recently proposed small-signal model for the hysteretic comparator. The analytical findings are verified experimentally as well as by simulation. Experimentally, the use of hysteretic self......This paper presents a theoretical and experimental comparison of the standard PWM/PID voltage-mode control method for single-phase buck converters with two highperformance self-oscillating (a.k.a. sliding mode) control methods. The application considered is ultra-fast tracking power supplies...... (UFTPSs) for RF power amplifiers, where the switching converter needs to track a varying reference voltage precisely and quickly while maintaining low output impedance. The small-signal analyses performed on the different controllers show that the hysteretic-type controller can achieve the highest loop...

  2. Intermittency and bifurcation in SEPICs under voltage-mode control (United States)

    Liu, Fang


    A stroboscopic map for voltage-controlled single ended primary inductor converter (SEPIC) with pulse width modulation (PWM) is presented, where low-frequency oscillating phenomena such as quasi-periodic and intermittent quasi-periodic bifurcations occurring in the system are captured by numerical and experimental methods. According to bifurcation diagrams and nonlinear dynamical theory, the characteristics of the low-frequency oscillation and the mechanism for the appearance of the low-frequency oscillation are investigated. It is shown that as the controller parameter varies, the change in the conduction mode takes place from the continuous conduction mode (CCM) under the originally stable period one and high periodic orbits to the intermittent changes between CCM and discontinuous conduction mode (DCM), which may be related to the losing stability of the system and brought the system to exhibiting low-frequency oscillating behaviour in the time domain. Moreover, the occurrence of the intermittent quasi-periodic oscillation reflects that the system undergoes a Neimark-Sacker bifurcation.

  3. State space analysis of boost DC/DC converter with voltage mode control (United States)

    Shenoy, K. Latha; Nayak, C. Gurudas; Mandi, Rajashekar P.


    The boost converter belongs to the family of indirect energy transfer converters. The inductor stores energy during switch on and the output capacitor deliver power to the load. During switch off condition, the stored inductive energy appears in series with the input source and supply the output. The paper deals with the small signal analysis of dc-dc boost converter. It is used in modeling the closed loop converter parameters. The boost converter produces an undesirable Right-Half Plane Zero (RHPZ) in the small signal analysis due to which the implementation of voltage mode control needs attention. This requires compensating the regulator such that the crossover frequency occurs well below the frequency of the RHP zero. The paper describes modeling of voltage mode control boost converter operating in continuous conduction mode.

  4. Voltage Mode Universal Biquad Using CCCII

    Directory of Open Access Journals (Sweden)

    Ashish Ranjan


    Full Text Available This paper proposes a multi-input single-output (MISO second-order active-C voltage mode (VM universal filter using two second-generation current-controlled current conveyors (CCCIIs and two equal-valued capacitors. The proposed circuit realizes low pass, band pass, high pass, all pass, and notch responses from the same topology. The filter uses-minimum number of passive components and no resistor which is suitable for IC Design. The filter enjoys low-sensitivity performance and exhibits electronic and orthogonal tunability of pole frequency (0 and quality factor (0 via bias current of CCCIIs. PSPICE simulation results confirm the theory.

  5. Voltage Mode Single CDBA Based Multifunction Filter (United States)

    Gupta, Priyanka; Pandey, Rajeshwari; Pandey, Neeta


    A voltage mode multifunction second order filter topology employing single current differencing buffered amplifier (CDBA) has been proposed in this paper. This topology can be used to synthesize low pass (LP), band pass (BP), and high pass (HP) filter functions with appropriate admittance choices. This configuration is a suitable choice for implementing filters with high quality factor. The demonstration of the proposed configuration is done through PSPICE simulations. The CDBA block is realized using CMOS 0.18µm technology. The simulation results are found in close agreement with the theoretical results.

  6. Current and Voltage Mode Multiphase Sinusoidal Oscillators Using CBTAs

    Directory of Open Access Journals (Sweden)

    M. Sagbas


    Full Text Available Current-mode (CM and voltage-mode (VM multiphase sinusoidal oscillator (MSO structures using current backward transconductance amplifier (CBTA are proposed. The proposed oscillators can generate n current or voltage signals (n being even or odd equally spaced in phase. n+1 CBTAs, n grounded capacitors and a grounded resistor are used for nth-state oscillator. The oscillation frequency can be independently controlled through transconductance (gm of the CBTAs which are adjustable via their bias currents. The effects caused by the non-ideality of the CBTA on the oscillation frequency and condition have been analyzed. The performance of the proposed circuits is demonstrated on third-stage and fifth-stage MSOs by using PSPICE simulations based on the 0.25 µm TSMC level-7 CMOS technology parameters.

  7. Voltage-Mode All-Pass Filters Including Minimum Component Count Circuits

    Directory of Open Access Journals (Sweden)

    Sudhanshu Maheshwari


    Full Text Available This paper presents two new first-order voltage-mode all-pass filters using a single-current differencing buffered amplifier and four passive components. Each circuit is compatible to a current-controlled current differencing buffered amplifier with only two passive elements, thus resulting in two more circuits, which employ a capacitor, a resistor, and an active element, thus using a minimum of active and passive component counts. The proposed circuits possess low output impedance, and hence can be easily cascaded for voltage-mode systems. PSPICE simulation results are given to confirm the theory.

  8. Third-order voltage-mode active-C band pass filter (United States)

    Ranjan, Ashish; Ghosh, Mourina; Paul, Sajal K.


    In this research article, a new third-order voltage-mode active-C asymmetrical band pass filter is proposed. It uses three numbers of current-controlled current conveyors and three numbers of equal-valued capacitors. The topology has the following important features: uses only three active elements, uses three capacitors, uses all grounded capacitors and no resistor is suitable for integrated circuit design, there is no matching constraint, high input impedance, low output impedance, central frequency can easily be electronically controlled by bias current, and frequency response is asymmetrical in nature. The application of the proposed topology in the realisation of a voltage-mode sixth-order symmetrical band pass filter has been demonstrated. The workability of the proposed topology and sixth-order filter has been confirmed by simulation results using 0.35-µm Austria Micro Systems complementary metal oxide semiconductor technology.

  9. Voltage-Mode Four-Phase Sinusoidal Generator and Its Useful Extensions

    Directory of Open Access Journals (Sweden)

    Sudhanshu Maheshwari


    Full Text Available This paper introduces a new voltage-mode second-order sinusoidal generator circuit with four active elements and six passive elements, including grounded capacitors. The frequency and condition of oscillation can be independently controlled. The effect of active element’s nonidealities and parasitic effects is also studied; the proposed topology is good in absorbing several parasitic elements involved with the active elements. The circuit is advantageous for generating high frequency signals which is demonstrated for 25 MHz outputs. Several circuit extensions are also given which makes the new proposal useful for real circuit adoption. The proposed theory is validated through simulation results.

  10. Supplementary High-Input Impedance Voltage-Mode Universal Biquadratic Filter Using DVCCs

    Directory of Open Access Journals (Sweden)

    Jitendra Mohan


    Full Text Available To further extend the existing knowledge on voltage-mode universal biquadratic filter, in this paper, a new biquadratic filter circuit with single input and multiple outputs is proposed, employing three differential voltage current conveyors (DVCCs, three resistors, and two grounded capacitors. The proposed circuit realizes all the standard filter functions, that is, high-pass, band-pass, low-pass, notch, and all-pass filters simultaneously. The circuit enjoys the feature of high-input impedance, orthogonal control of resonance angular frequency (o, and quality factor (Q via grounded resistor and the use of grounded capacitors which is ideal for IC implementation.

  11. Single Active Element Based Voltage-Mode Multifunction Filter

    Directory of Open Access Journals (Sweden)

    Jitendra Mohan


    Full Text Available The paper presents a new voltage-mode multifunction filter. The proposed filter employs single modified fully differential second generation current conveyor (FDCCII, two grounded capacitors, and three resistors. The proposed circuit enjoys the employment of two grounded capacitors (attractive for absorbing shunt parasitic capacitance and ideal for IC implementation. The proposed circuit provides all five generic filter responses (low pass (LP, high pass (HP, band pass (BP, notch (NH, and all pass (AP filter responses simultaneously with single input. The novel proposed filter has low active and passive sensitivities. A number of time domain and frequency domain simulation results depicted through PSPICE using 0.18 µm TSMC process parameters are included to validate the theory. The proposed circuit is expected to enhance the existing knowledge on the subject.

  12. Digitally Programmable High-Q Voltage Mode Universal Filter

    Directory of Open Access Journals (Sweden)

    D. Singh


    Full Text Available A new low-voltage low-power CMOS current feedback amplifier (CFA is presented in this paper. This is used to realize a novel digitally programmable CFA (DPCFA using transistor arrays and MOS switches. The proposed realizations nearly allow rail-to-rail swing capability at all the ports. Class-AB output stage ensures low power dissipation and high current drive capability. The proposed CFA/ DPCFA operates at supply voltage of ±0.75 V and exhibits bandwidth better than 95 MHz. An application of the DPCFA to realize a novel voltage mode high-Q digitally programmable universal filter (UF is given. Performances of all the proposed circuits are verified by PSPICE simulation using TSMC 0.25μm technology parameters.

  13. A Low-Voltage Electronically Tunable MOSFET-C Voltage-Mode First-Order All-Pass Filter Design


    Metin, B.; N. Herencsar; O. Cicekoglu


    This paper presents a simple electronically tunable voltage-mode first-order all-pass filter realization with MOSFET-C technique. In comparison to the classical MOSFET-C filter circuits that employ active elements including large number of transistors the proposed circuit is only composed of a single two n-channel MOSFET-based inverting voltage buffer, three passive components, and one NMOS-based voltage-controlled resistor, which is with advantage used to electronically control the pole freq...

  14. Systems and methods for providing power to a load based upon a control strategy

    Energy Technology Data Exchange (ETDEWEB)

    Perisic, Milun; Kajouke, Lateef A; Ransom, Ray M


    Systems and methods are provided for an electrical system. The electrical system includes a load, an interface configured to receive a voltage from a voltage source, and a controller configured to receive the voltage from the voltage source through the interface and to provide a voltage and current to the load. Wherein, when the controller is in a constant voltage mode, the controller provides a constant voltage to the load, when the controller is in a constant current mode, the controller provides a constant current to the load, and when the controller is in a constant power mode, the controller provides a constant power to the load.

  15. Voltage-Mode Multifunction Biquadratic Filter with One Input and Six Outputs Using Two ICCIIs

    Directory of Open Access Journals (Sweden)

    Hua-Pin Chen


    Full Text Available A novel voltage-mode multifunction biquadratic filter with one input and six outputs is presented. The proposed circuit can realize inverting and noninverting low-pass, bandpass, and high-pass filters, simultaneously, by using two inverting second-generation current conveyors (ICCIIs, two grounded capacitors, and four resistors. Moreover, the proposed circuit offers the following attractive advantages: no requirements for component matching conditions, the use of only grounded capacitors, and low active and passive sensitivities. HSPICE and MATLAB simulations results are provided to demonstrate the theoretical analysis.

  16. Voltage-Mode Multifunction Biquadratic Filters Using New Ultra-Low-Power Differential Difference Current Conveyors

    Directory of Open Access Journals (Sweden)

    M. Kumngern


    Full Text Available This paper presents two low-power voltage-mode multifunction biquadratic filters using differential difference current conveyors. Each proposed circuit employs three differential difference current conveyors, two grounded capacitors and two grounded resistors. The low-voltage ultra-low-power differential difference current conveyor is used to provide low-power consumption of the proposed filters. By appropriately connecting the input and output terminals, the proposed filters can provide low-pass, band-pass, high-pass, band-stop and all-pass voltage responses at high-input terminals, which is a desirable feature for voltage-mode operations. The natural frequency and the quality factor can be orthogonally set by adjusting the circuit components. For realizing all the filter responses, no inverting-type input signal requirements as well as no component-matching conditional requirements are imposed. The incremental parameter sensitivities are also low. The characteristics of the proposed circuits are simulated by using PSPICE simulators to confirm the presented theory.

  17. A Low-Voltage Electronically Tunable MOSFET-C Voltage-Mode First-Order All-Pass Filter Design

    Directory of Open Access Journals (Sweden)

    B. Metin


    Full Text Available This paper presents a simple electronically tunable voltage-mode first-order all-pass filter realization with MOSFET-C technique. In comparison to the classical MOSFET-C filter circuits that employ active elements including large number of transistors the proposed circuit is only composed of a single two n-channel MOSFET-based inverting voltage buffer, three passive components, and one NMOS-based voltage-controlled resistor, which is with advantage used to electronically control the pole frequency of the filter in range 103 kHz to 18.3 MHz. The proposed filter is also very suitable for low-voltage operation, since between its supply rails it uses only two MOSFETs. In the paper the effect of load is investigated. In addition, in order to suppress the effect of non-zero output resistance of the inverting voltage buffer, two compensation techniques are also introduced. The theoretical results are verified by SPICE simulations using PTM 90 nm level-7 CMOS process BSIM3v3 parameters, where +/- 0.45 V supply voltages are used. Moreover, the behavior of the proposed filter was also experimentally measured using readily available array transistors CD4007UB by Texas Instruments.

  18. High-Input and Low-Output Impedance Voltage-Mode Universal DDCC and FDCCII Filter (United States)

    Chen, Hua-Pin; Yang, Wan-Shing

    Despite the extensive literature on current conveyor-based universal (namely, low-pass, band-pass, high-pass, notch, and all-pass) biquads with three inputs and one output, no filter circuits have been reported to date which simultaneously achieve the following seven important features: (i) employment of only two current conveyors, (ii) employment of only grounded capacitors, (iii) employment of only grounded resistors, (iv) high-input and low-output impedance, (v) no need to employ inverting type input signals, (vi) no need to impose component choice conditions to realize specific filtering functions, and (vii) low active and passive sensitivity performances. This letter describes a new voltage-mode biquad circuit that satisfies all the above features simultaneously, and without trade-offs.

  19. New Voltage-Mode All-pass Filter Topology Employing Single Current Operational Amplifier

    Directory of Open Access Journals (Sweden)

    Hasan Çiçekli


    Full Text Available In this paper, a new voltage-mode all-pass filter topology based on single current operational amplifier (COA and the implementation of COA by using current conveyors are presented. The proposed topology employs three admittances and single active circuit element. COA implementation by using current conveyor blocks as sub-circuit contributes to workability of the COA employing circuits by using commercially available integrated circuits that can be employed as current conveyor. The validity of the proposed filter is verified by PSPICE simulation programme by using the MOSIS 0.35 micron CMOS process parameters. The simulation results agree well with the theoretical analysis and the circuit achieve a good total harmonic distortion (THD performance.

  20. A Comparative Analysis between GaN-Based Current and Voltage Mode Class-D and E PAs for Communications (United States)


    A Comparative Analysis between GaN-Based Current and Voltage Mode Class-D and E PAs for Communications Shishir Shukla and Jennifer Kitchen...programmability and efficiency. Radar and imaging systems that use constant envelope waveforms may exploit the advantages of highly nonlinear, or switched...709–717, Dec 2005. 7. T. Suetsugu and M. K. Kazimierczuk, “Off-Nominal Operation of Class-E Amplifier at Any Duty Ratio ,” IEEE Transactions on

  1. Single-Input Six-Output Voltage-Mode Filter Using Universal Voltage Conveyors (United States)

    Minarcik, Martin; Vrba, Kamil

    In this letter a new structure of multifunctional frequency filter using a universal voltage conveyor (UVC) is presented. The multifunctional circuit can realize a low-pass, high-pass and band-pass filter. All types of frequency filter can be realized as inverting or non-inverting. Advantages of the proposed structure are the independent control of the quality factor at the cut-off frequency and the low output impedance of output terminals. The computer simulations and measuring of particular frequency filters are depicted.

  2. Control system design method (United States)

    Wilson, David G [Tijeras, NM; Robinett, III, Rush D.


    A control system design method and concomitant control system comprising representing a physical apparatus to be controlled as a Hamiltonian system, determining elements of the Hamiltonian system representation which are power generators, power dissipators, and power storage devices, analyzing stability and performance of the Hamiltonian system based on the results of the determining step and determining necessary and sufficient conditions for stability of the Hamiltonian system, creating a stable control system based on the results of the analyzing step, and employing the resulting control system to control the physical apparatus.

  3. Three-Input Single-Output Voltage-Mode Multifunction Filter with Electronic Controllability Based on Single Commercially Available IC

    National Research Council Canada - National Science Library

    Supachai Klungtong; Dusit Thanapatay; Winai Jaikla


    .... The proposed filter is based on parallel RLC circuit. The filter provides five output filter responses, namely, band-pass (BP), band-reject (BR), low-pass (LP), high-pass (HP), and all-pass (AP) functions...

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  5. Methods in Logic Based Control

    DEFF Research Database (Denmark)

    Christensen, Georg Kronborg


    Desing and theory of Logic Based Control systems.Boolean Algebra, Karnaugh Map, Quine McClusky's algorithm. Sequential control design. Logic Based Control Method, Cascade Control Method. Implementation techniques: relay, pneumatic, TTL/CMOS,PAL and PLC- and Soft_PLC implementation. PLC...

  6. Chemical control methods and tools (United States)

    Steven Manning; James. Miller


    After determining the best course of action for control of an invasive plant population, it is important to understand the variety of methods available to the integrated pest management professional. A variety of methods are now widely used in managing invasive plants in natural areas, including chemical, mechanical, and cultural control methods. Once the preferred...

  7. Method for controlling brazing (United States)

    Hosking, F Michael [Albuquerque, NM; Hall, Aaron C [Albuquerque, NM; Givler, Richard C [Albuquerque, NM; Walker, Charles A [Albuquerque, NM


    A method for making a braze joint across a discontinuity in a work piece using alternating current. A filler metal is pre-placed at a location sufficiently close to the discontinuity such that, when an alternating current is applied across a work piece to heat the work piece and melt the filler metal, the filler metal is drawn into the discontinuity. The alternating current is maintained for a set residence time, generally less than 10 seconds and more particularly less than 3 seconds. The alternating current is then altered, generally by reducing the current and/or voltage such that the filler metal can solidify to form a braze joint of desired quality and thickness.

  8. Efficient 2,4-dichloronitrobenzene removal in the coupled BES-UASB reactor: Effect of external voltage mode. (United States)

    Chen, Hui; Gao, Xinyi; Wang, Caiqin; Shao, Junjie; Xu, Xiangyang; Zhu, Liang


    In this study, bioelectrochemical-upflow anaerobic sludge blanket (BES-UASB) system was developed for treatment of 2,4-dichloronitrobenzen (DClNB) containing wastewater to investigate the effect of external voltage with different supplying modes. Results showed that 2,4-dichloroaniline (DClAN) was under detection limit in R1 (applied with intermittent voltage) and R2 (applied with continuous voltage) when the DClNB loading increased from 25 to 100gm(3)d(-1) (hydraulic retention time (HRT) was decreased from 24 to 6h) while sudden accumulation of DClAN (1.7mgL(-1)) was observed in R0 (control). Dechlorination efficiency (DE) decreased to 32.7%, 45.0% and 45.3% in R0, R1 and R2 when HRT was further shortened to 4h. Microbial community analysis indicated the significant enrichment of dechlorination-related species in R1 and R2 compared with R0, e.g., Dehalobacter and Dehalococcoides. In summary, the BES-UASB system with intermittent voltage is an alternative process for efficient treatment of DClNB containing wastewater, and the energy input was reduced markedly. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Transformation method and wave control (United States)

    Chang, Zheng; Hu, Jin; Hu, Geng-Kai


    Transformation method provides an efficient way to control wave propagation by materials. The transformed relations for field and material during a transformation are essential to fulfill this method. We propose a systematic method to derive the transformed relations for a general physic process, the constraint conditions are obtained by considering geometrical and physical constraint during a mapping. The proposed method is applied to Navier's equation for elastodynamics, Helmholtz's equation for acoustic wave and Maxwell's equation for electromagnetic wave, the corresponding transformed relations are derived, which can be used in the framework of transformation method for wave control. We show that contrary to electromagnetic wave, the transformed relations are not uniquely determined for elastic wave and acoustic wave, so we have a freedom to choose them differently. Using the obtained transformed relations, we also provide some examples for device design, a concentrator for elastic wave, devices for illusion acoustic and illusion optics are conceived and validated by numerical simulations.

  10. Optimal control linear quadratic methods

    CERN Document Server

    Anderson, Brian D O


    This augmented edition of a respected text teaches the reader how to use linear quadratic Gaussian methods effectively for the design of control systems. It explores linear optimal control theory from an engineering viewpoint, with step-by-step explanations that show clearly how to make practical use of the material.The three-part treatment begins with the basic theory of the linear regulator/tracker for time-invariant and time-varying systems. The Hamilton-Jacobi equation is introduced using the Principle of Optimality, and the infinite-time problem is considered. The second part outlines the

  11. Coexistence of Controlling and Other Management Methods

    Directory of Open Access Journals (Sweden)

    Agnieszka Bieńkowska


    Full Text Available The effects of the coexistence of Controlling and other management methods (benchmarking, BPM, BPR, BSC, Competency-based Management, CRM, ERP, KM, LM, Outsourcing, Six Sigma, TQM have been analysed. The complexity and dynamics of modern management systems in fact require simultaneous and/or sequential application of many concepts and methods of management. Controlling is a comprehensive method with an interdisciplinary character, which acts as an integrating plane for many methods and techniques. The coexistence of controlling with other management methods depends on the type of relationship between controlling and these methods. In the main, however, coexistence should be beneficial for an organization. Theoretical concepts on the relations between controlling and other methods are thus empirically tested by analysing the effect of using selected management methods, both in conjunction with controlling, as well as separately (business, efficiency, management, social and environmental effects. One-Way ANOVA was used based on a sample of 167 Polish organizations. (original abstract

  12. New tuning method for PID controller. (United States)

    Shen, Jing-Chung


    In this paper, a tuning method for proportional-integral-derivative (PID) controller and the performance assessment formulas for this method are proposed. This tuning method is based on a genetic algorithm based PID controller design method. For deriving the tuning formula, the genetic algorithm based design method is applied to design PID controllers for a variety of processes. The relationship between the controller parameters and the parameters that characterize the process dynamics are determined and the tuning formula is then derived. Using simulation studies, the rules for assessing the performance of a PID controller tuned by the proposed method are also given. This makes it possible to incorporate the capability to determine if the PID controller is well tuned or not into an autotuner. An autotuner based on this new tuning method and the corresponding performance assessment rules is also established. Simulations and real-time experimental results are given to demonstrate the effectiveness and usefulness of these formulas.

  13. Methods for robust PID control


    Bajcinca, Naim


    A comprehensive theory for robust PID control in continuous-time and discrete-time domain is reviewed in this paper. For a given finite set of linear time invariant plants, algorithms for fast computation of robustly stabilizing regions in the ($k_P, k_I, k_D$)-parameter space are introduced. The main impetus is given by the fact that non-convex stable regions in the PID parameter space can be built up by convex polygonal slices. A simple and an elegant theory evolved in the last few years up...

  14. Quality Control Guidelines for SAM Chemical Methods (United States)

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  18. Adaptive Method Using Controlled Grid Deformation

    Directory of Open Access Journals (Sweden)



    Full Text Available The paper presents an adaptive method using the controlled grid deformation over an elastic, isotropic and continuous domain. The adaptive process is controlled with the principal strains and principal strain directions and uses the finite elements method. Numerical results are presented for several test cases.

  19. Evaluation of Design Methods for Geometric Control

    DEFF Research Database (Denmark)

    Kymmel, Mogens; Beran, M.; Foldager, L.


    Geometric control can produce desirable control by decoupling the input disturbances from the selected output variables. The basic principle for this method was originally introduced by Wonham. The mathematical complexity involved, however, makes the method very hard to get accepted by the chemic...... of the designer, transparency, computer demand, and potential for pole shift....

  20. Indigenous Control Methods for Parasites among Pastoralists ...

    African Journals Online (AJOL)

    Tree felling and bush burning were constraints to utilization of the control methods. The study concluded that indigenous control methods were well established and utilized by the respondents. It is recommended that laws banning bush burning and indiscriminate tree felling be re-enforced in order to preserve indigenous ...

  1. Controling twisting of wells by turbine method

    Energy Technology Data Exchange (ETDEWEB)

    Markov, O.A.; Burkin, Yu. V.; Dveriy, S.V.; Ivanov, B.A.; Romaniv, A.V.; Sereda, N.G.


    Methods are examined for controlling twisting of wells by turbine method using eccentric device and rotor method applying oriented assymmetrical flushing of the bit zone, as well as technique of studying the operation of drilling string in a twisted wellby computer.

  2. Comparing three patient-controlled analgesia methods. (United States)

    Hoare, K; Sousa, K H; Person, L; De Ryke, P; Piper, J


    Among 301 patients randomly assigned to use one of three methods for patient-controlled analgesia (PCA), no statistically significant differences were found for self-reported pain or acceptability of PCA method. Methods yielded differences in on-demand bolus analgesia use and number of symptoms.

  3. On Methods of Geodetic Control Densification

    Directory of Open Access Journals (Sweden)

    Zdeněk Nevosád


    Full Text Available Newly established CZEPOS network on the territory of Czech Republic enlarges the point positioning possibilities by DGPS and RTK satellite methods. Control densification points can be measured by both the satellite and terrestrial methods now. Methods of common parametric adjustment of satellite and terrestrial quantitiesare emphasized a in selected processing procedures, which give results of a needed quality.

  4. Robust Control Methods for a Recycle Bioreactor

    Directory of Open Access Journals (Sweden)

    Cosmin IONETE


    Full Text Available The paper presents a robust control design strategy for bioprocesses, which are characterized by strongly nonlinear dynamics. More precisely, we present the H2 methodology in order to compute the controller for a recycle Continuous Stirred Tank Bioreactor (CSTB. We consider a general method of formulating control problem, which makes use of linear fractional transformation as introduced by Doyle (1978. The formulation makes use of the general two-port configuration of the generalized plant with a generalized controller. The H2 norm is the quadratic criterion used in optimal control as LQG. The overall control objective is to minimize the H2 norm of the transfer matrix function from the weighted exogenous inputs to the weighted controlled outputs. The advantage of H2 control technique, which uses the linearized model of the CSTB, is that it is completely automated and very flexible. Finally, we prove that the closed loop control structure has very good inner robustness.

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  6. Method of controlling fusion reaction rates (United States)

    Kulsrud, Russell M.; Furth, Harold P.; Valeo, Ernest J.; Goldhaber, Maurice


    A method of controlling the reaction rates of the fuel atoms in a fusion reactor comprises the step of polarizing the nuclei of the fuel atoms in a particular direction relative to the plasma confining magnetic field. Fusion reaction rates can be increased or decreased, and the direction of emission of the reaction products can be controlled, depending on the choice of polarization direction.

  7. Augmented Lagrangian Method For Discretized Optimal Control ...

    African Journals Online (AJOL)

    With the aid of Augmented Lagrangian method, a quadratic function with a control operator (penalized matrix) amenable to conjugate gradient method is generated. Numerical experiments verify the efficiency of the proposed technique which compares much more favourably to the existing scheme. Keywords: Trapezoidal ...

  8. LED lamp color control system and method (United States)

    Gaines, James; Clauberg, Bernd; Van Erp, Josephus A.M.


    An LED lamp color control system and method including an LED lamp having an LED controller 58; and a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 determines whether the LED source 80 is in a feedback controllable range, stores measured optical flux for the LED source 80 when the LED source 80 is in the feedback controllable range, and bypasses storing the measured optical flux when the LED source 80 is not in the feedback controllable range.

  9. Choosing an optimum sand control method

    Directory of Open Access Journals (Sweden)

    Ehsan Khamehchi


    Full Text Available Formation sand control is always one of the main concerns of production engineers. There are some different methods to prevent sand production. Choosing a method for preventing formation sand production depends on different reservoir parameters and politic and economic conditions. Sometimes, economic and politic conditions are more effective to choose an optimum than reservoir parameters. Often, simultaneous investigation of politic and economic conditions with reservoir parameters has different results with what is expected. So, choosing the best sand control method is the result of thorough study. Global oil price, duration of sand control project and costs of necessary equipment for each method as economic and politic conditions and well productivity index as reservoir parameter are the main parameters studied in this paper.

  10. Robustness analysis method for orbit control (United States)

    Zhang, Jingrui; Yang, Keying; Qi, Rui; Zhao, Shuge; Li, Yanyan


    Satellite orbits require periodical maintenance due to the presence of perturbations. However, random errors caused by inaccurate orbit determination and thrust implementation may lead to failure of the orbit control strategy. Therefore, it is necessary to analyze the robustness of the orbit control methods. Feasible strategies which are tolerant to errors of a certain magnitude can be developed to perform reliable orbit control for the satellite. In this paper, first, the orbital dynamic model is formulated by Gauss' form of the planetary equation using the mean orbit elements; the atmospheric drag and the Earth's non-spherical perturbations are taken into consideration in this model. Second, an impulsive control strategy employing the differential correction algorithm is developed to maintain the satellite trajectory parameters in given ranges. Finally, the robustness of the impulsive control method is analyzed through Monte Carlo simulations while taking orbit determination error and thrust error into account.

  11. Control analysis and experimental verification of a practical dc–dc boost converter

    Directory of Open Access Journals (Sweden)

    Saswati Swapna Dash


    Full Text Available This paper presents detailed open loop and closed loop analysis on boost dc–dc converter for both voltage mode control and current mode control. Here the boost dc–dc converter is a practical converter considering all possible parasitic elements like ESR and on state voltage drops. The open loop control, closed loop current mode control and voltage mode control are verified. The comparative study of all control techniques is presented. The PI compensator for closed loop current mode control is designed using these classical techniques like root locus technique and bode diagram. The simulation results are validated with the experimental results of voltage mode control for both open loop and closed loop control.

  12. Control of Liquid Sloshing Container using Active Force Control Method (United States)

    Setyo Purnomo, Didik; Rachmad Anom Besari, Adnan; Darojah, Zaqiatud


    This paper presents a robust control method to relieve the sloshing of liquid container transport using Active Force Control (AFC) method. A model of two degree-of-freedom (2-DOF) liquid container transfer was implemented in this research as the main dynamical system to be controlled. The surface of liquid is maintained in a flat position, so that changes the slope of liquid surface countered by changing the acceleration of container. The focus of this research is how to use AFC method being applied to the system, so that it can suppress liquid sloshing. The control scheme were simulated, compare between PID-AFC and pure PID. Simulations has been conducted, the results show that the PID-AFC have superior performance to suppress the sloshing compared with pure PID, especially if disturbance occurred.


    Energy Technology Data Exchange (ETDEWEB)



    A bifurcation subsystem based model and controller reduction approach is presented. Using this approach a robust {micro}-synthesis SVC control is designed for interarea oscillation and voltage control based on a small reduced order bifurcation subsystem model of the full system. The control synthesis problem is posed by structured uncertainty modeling and control configuration formulation using the bifurcation subsystem knowledge of the nature of the interarea oscillation caused by a specific uncertainty parameter. Bifurcation subsystem method plays a key role in this paper because it provides (1) a bifurcation parameter for uncertainty modeling; (2) a criterion to reduce the order of the resulting MSVC control; and (3) a low order model for a bifurcation subsystem based SVC (BMSVC) design. The use of the model of the bifurcation subsystem to produce a low order controller simplifies the control design and reduces the computation efforts so significantly that the robust {micro}-synthesis control can be applied to large system where the computation makes robust control design impractical. The RGA analysis and time simulation show that the reduced BMSVC control design captures the center manifold dynamics and uncertainty structure of the full system model and is capable of stabilizing the full system and achieving satisfactory control performance.

  14. Evaluation of Controller Tuning Methods Applied to Distillation Column Control

    DEFF Research Database (Denmark)

    Nielsen, Kim; W. Andersen, Henrik; Kümmel, Professor Mogens

    A frequency domain approach is used to compare the nominal performance and robustness of dual composition distillation column control tuned according to Ziegler-Nichols (ZN) and Biggest Log Modulus Tuning (BLT) for three binary distillation columns, WOBE, LUVI and TOFA. The scope...... of this is to examine whether ZN and BLT design yield satisfactory control of distillation columns. Further, PI controllers are tuned according to a proposed multivariable frequency domain method. A major conclusion is that the ZN tuned controllers yield undesired overshoot and oscillation and poor stability robustness...

  15. Control method for physical systems and devices (United States)

    Guckenheimer, John


    A control method for stabilizing systems or devices that are outside the control domain of a linear controller is provided. When applied to nonlinear systems, the effectiveness of this method depends upon the size of the domain of stability that is produced for the stabilized equilibrium. If this domain is small compared to the accuracy of measurements or the size of disturbances within the system, then the linear controller is likely to fail within a short period. Failure of the system or device can be catastrophic: the system or device can wander far from the desired equilibrium. The method of the invention presents a general procedure to recapture the stability of a linear controller, when the trajectory of a system or device leaves its region of stability. By using a hybrid strategy based upon discrete switching events within the state space of the system or device, the system or device will return from a much larger domain to the region of stability utilized by the linear controller. The control procedure is robust and remains effective under large classes of perturbations of a given underlying system or device.

  16. Temperature effects and compensation-control methods. (United States)

    Xia, Dunzhu; Chen, Shuling; Wang, Shourong; Li, Hongsheng


    In the analysis of the effects of temperature on the performance of microgyroscopes, it is found that the resonant frequency of the microgyroscope decreases linearly as the temperature increases, and the quality factor changes drastically at low temperatures. Moreover, the zero bias changes greatly with temperature variations. To reduce the temperature effects on the microgyroscope, temperature compensation-control methods are proposed. In the first place, a BP (Back Propagation) neural network and polynomial fitting are utilized for building the temperature model of the microgyroscope. Considering the simplicity and real-time requirements, piecewise polynomial fitting is applied in the temperature compensation system. Then, an integral-separated PID (Proportion Integration Differentiation) control algorithm is adopted in the temperature control system, which can stabilize the temperature inside the microgyrocope in pursuing its optimal performance. Experimental results reveal that the combination of microgyroscope temperature compensation and control methods is both realizable and effective in a miniaturized microgyroscope prototype.


    African Journals Online (AJOL)



  18. Methods of control the machining process

    Directory of Open Access Journals (Sweden)

    Yu.V. Petrakov


    Full Text Available Presents control methods, differentiated by the time of receipt of information used: a priori, a posteriori and current. When used a priori information to determine the mode of cutting is carried out by simulation the process of cutting allowance, where the shape of the workpiece and the details are presented in the form of wireframes. The office for current information provides for a system of adaptive control and modernization of CNC machine, where in the input of the unit shall be computed by using established optimization software. For the control by a posteriori information of the proposed method of correction of shape-generating trajectory in the second pass measurement surface of the workpiece formed by the first pass. Developed programs that automatically design the adjusted file for machining.

  19. Actively controlled vibration welding system and method (United States)

    Cai, Wayne W.; Kang, Bongsu; Tan, Chin-An


    A vibration welding system includes a controller, welding horn, an active material element, and anvil assembly. The assembly may include an anvil body connected to a back plate and support member. The element, e.g., a piezoelectric stack or shape memory alloy, is positioned with respect to the assembly. The horn vibrates in a desirable first direction to form a weld on a work piece. The element controls any vibrations in a second direction by applying calibrated response to the anvil body in the second direction. A method for controlling undesirable vibrations in the system includes positioning the element with respect to the anvil assembly, connecting the anvil body to the support member through the back plate, vibrating the horn in a desirable first direction, and transmitting an input signal to the element to control vibration in an undesirable second direction.

  20. Control and estimation methods over communication networks

    CERN Document Server

    Mahmoud, Magdi S


    This book provides a rigorous framework in which to study problems in the analysis, stability and design of networked control systems. Four dominant sources of difficulty are considered: packet dropouts, communication bandwidth constraints, parametric uncertainty, and time delays. Past methods and results are reviewed from a contemporary perspective, present trends are examined, and future possibilities proposed. Emphasis is placed on robust and reliable design methods. New control strategies for improving the efficiency of sensor data processing and reducing associated time delay are presented. The coverage provided features: ·        an overall assessment of recent and current fault-tolerant control algorithms; ·        treatment of several issues arising at the junction of control and communications; ·        key concepts followed by their proofs and efficient computational methods for their implementation; and ·        simulation examples (including TrueTime simulations) to...

  1. Methods of algebraic geometry in control theory

    CERN Document Server

    Falb, Peter


    "Control theory represents an attempt to codify, in mathematical terms, the principles and techniques used in the analysis and design of control systems. Algebraic geometry may, in an elementary way, be viewed as the study of the structure and properties of the solutions of systems of algebraic equations. The aim of this book is to provide access to the methods of algebraic geometry for engineers and applied scientists through the motivated context of control theory" .* The development which culminated with this volume began over twenty-five years ago with a series of lectures at the control group of the Lund Institute of Technology in Sweden. I have sought throughout to strive for clarity, often using constructive methods and giving several proofs of a particular result as well as many examples. The first volume dealt with the simplest control systems (i.e., single input, single output linear time-invariant systems) and with the simplest algebraic geometry (i.e., affine algebraic geometry). While this is qui...

  2. The statistical process control methods - SPC

    Directory of Open Access Journals (Sweden)

    Floreková Ľubica


    Full Text Available Methods of statistical evaluation of quality – SPC (item 20 of the documentation system of quality control of ISO norm, series 900 of various processes, products and services belong amongst basic qualitative methods that enable us to analyse and compare data pertaining to various quantitative parameters. Also they enable, based on the latter, to propose suitable interventions with the aim of improving these processes, products and services. Theoretical basis and applicatibily of the principles of the: - diagnostics of a cause and effects, - Paret analysis and Lorentz curve, - number distribution and frequency curves of random variable distribution, - Shewhart regulation charts, are presented in the contribution.

  3. Computational Methods for Design, Control and Optimization (United States)


    Sensitivity Computations, 49 (2005), pp. 1889 - 1903.. 8. Y. Cao, T. L. Herdman and Y. Xu, A Hybrid Collocation Method for Volterra Integral Equations ...scaleRiccati equations that arise in a variety of control and estimation problems. The results imply that, even when the Riccati equations are used for...and optimization of hybrid systems governed by partial differential equations that are typical in aerospace systems. The focus of the research is on non

  4. Control system for heliostats and method

    Energy Technology Data Exchange (ETDEWEB)

    Gerwin, H. L.


    A control system and method for a heliostat or a system of heliostats which operates to maintain the sunbeam properly centered with respect to an associated tracking head and tracks the sun for proper elevational and azimuthal orientation of the heliostat. The tracking date is stored in memory and utilized to reset the heliostat at night for proper orientation during the next days tracking and/or for proper orientation during sunless periods of the day. Each heliostat is therefore self-tracking.

  5. New method of control of tooth whitening (United States)

    Angelov, I.; Mantareva, V.; Gisbrecht, A.; Valkanov, S.; Uzunov, Tz.


    New methods of control of tooth bleaching stages through simultaneous measurements of a reflected light and a fluorescence signal are proposed. It is shown that the bleaching process leads to significant changes in the intensity of a scattered signal and also in the shape and intensity of the fluorescence spectra. Experimental data illustrate that the bleaching process causes essential changes in the teeth discoloration in short time as 8-10 min from the beginning of the application procedure. The continuation of the treatment is not necessary moreover the probability of the enamel destroy increases considerably. The proposed optical back control of tooth surface is a base for development of a practical set up to control the duration of the bleaching procedure.

  6. The fractional - order controllers: Methods for their synthesis and application


    Petras, I.


    This paper deals with fractional-order controllers. We outline mathematical description of fractional controllers and methods of their synthesis and application. Synthesis method is a modified root locus method for fractional-order systems and fractional-order controllers. In the next section we describe how to apply the fractional controller on control systems.

  7. Three-Input Single-Output Electronically Controllable Dual-Mode Universal Biquad Filter Using DO-CCCIIs

    Directory of Open Access Journals (Sweden)

    M. Siripruchyanun


    Full Text Available This article presents a dual-mode (voltage-mode and current-mode universal biquadratic filter performing completely standard functions: lowpass, highpass, bandpass, band-reject, and allpass functions, based on plus-type dual-output second-generation, current controlled, current conveyor (DO-CCCII+. The features of the circuit are that the bandwidth and natural frequency can be tuned electronically via the input bias currents: the circuit description is very simple, consisting of merely 2 DO-CCCIIs and 2 capacitors: the circuit can provide either the voltage-mode or current-mode filter without changing circuit topology. Additionally, each function response can be selected by suitably selecting input signals with digital method. Without any external resistors, the proposed circuit is very suitable to further develop into an integrated circuit. The PSPICE simulation results are depicted. The given results agree well with the theoretical anticipation. The maximum power consumption is approximately 1.81 mW at ±1.5 V supply voltages.

  8. Synchronous Control Method and Realization of Automated Pharmacy Elevator (United States)

    Liu, Xiang-Quan

    Firstly, the control method of elevator's synchronous motion is provided, the synchronous control structure of double servo motor based on PMAC is accomplished. Secondly, synchronous control program of elevator is implemented by using PMAC linear interpolation motion model and position error compensation method. Finally, the PID parameters of servo motor were adjusted. The experiment proves the control method has high stability and reliability.

  9. Internal combustion engine and method for control (United States)

    Brennan, Daniel G


    In one exemplary embodiment of the invention an internal combustion engine includes a piston disposed in a cylinder, a valve configured to control flow of air into the cylinder and an actuator coupled to the valve to control a position of the valve. The internal combustion engine also includes a controller coupled to the actuator, wherein the controller is configured to close the valve when an uncontrolled condition for the internal engine is determined.

  10. General Quality Control (QC) Guidelines for SAM Methods (United States)

    Learn more about quality control guidelines and recommendations for the analysis of samples using the methods listed in EPA's Selected Analytical Methods for Environmental Remediation and Recovery (SAM).

  11. The Robust Control Mixer Module Method for Control Reconfiguration

    DEFF Research Database (Denmark)

    Yang, Z.; Blanke, M.


    into a LTI dynamical system, and furthermore multiple dynamical control mixer modules can be employed in our consideration. The H_{\\infty} control theory is used for the analysis and design of the robust control mixer modules. Finally, one practical robot arm system as benchmark is used to test the proposed...

  12. Assessment of heliostat control system methods

    Energy Technology Data Exchange (ETDEWEB)

    Pearson, J; Chen, B


    Automatic control and communication between the major components in solar thermal central receiver systems is critically needed for the optimal and safe operation of these systems. This report assesses novel and cost-effective approaches to the control of the solar collector field and the communication with the central plant computer/control system. The authors state that radio frequency and carrier-current communication approaches have the greatest potential to improve cost-effectiveness relative to the current dedicated control wiring approaches. In addition, based on their analysis, the authors recommend distributed control, which is becoming an industry-wide control standard, for the individual concentrators within the collector field rather than the current central computer approach. The vastly improved cost and performance ofmicroprocessors and other solid-state electronics, which has continually and rapidly proceeded for more than five years, is the major reason for these conclusions.

  13. System and method for controlling microgrid (United States)

    Bose, Sumit [Niskayuna, NY; Achilles, Alfredo Sebastian [Bavaria, DE; Liu, Yan [Ballston Lake, NY; Ahmed, Emad Ezzat [Munich, DE; Garces, Luis Jose [Niskayuna, NY


    A system for controlling a microgrid includes microgrid assets and a tieline for coupling the microgrid to a bulk grid; and a tieline controller coupled to the tieline. At least one of the microgrid assets comprises a different type of asset than another one of the microgrid assets. The tieline controller is configured for providing tieline control signals to adjust active and reactive power in respective microgrid assets in response to commands from the bulk grid operating entity, microgrid system conditions, bulk grid conditions, or combinations thereof.

  14. Systems and methods for controlling flame instability

    KAUST Repository

    Cha, Min Suk


    A system (62) for controlling flame instability comprising: a nozzle (66) coupled to a fuel supply line (70), an insulation housing (74) coupled to the nozzle, a combustor (78) coupled to the nozzle via the insulation housing, where the combustor is grounded (80), a pressure sensor (82) coupled to the combustor and configured to detect pressure in the combustor, and an instability controlling assembly coupled to the pressure sensor and to an alternating current power supply (86), where, the instability controlling assembly can control flame instability of a flame in the system based on pressure detected by the pressure sensor.

  15. The novel control method of switched reluctance generator

    Directory of Open Access Journals (Sweden)

    Bogusz Piotr


    Full Text Available In the paper, a novel control method of a switched reluctance generator was discussed. The presented control method allows a rotor rotating at high speed to enter the continuous-conduction mode which causes an increase of generated output power. A control function of the presented method was given as well as simulation and laboratory tests.

  16. Methods and apparatus for controlling rotary machines (United States)

    Bagepalli, Bharat Sampathkumaran [Niskayuna, NY; Jansen, Patrick Lee [Scotia, NY; Barnes, Gary R [Delanson, NY; Fric, Thomas Frank [Greer, SC; Lyons, James Patrick Francis [Niskayuna, NY; Pierce, Kirk Gee [Simpsonville, SC; Holley, William Edwin [Greer, SC; Barbu, Corneliu [Guilderland, NY


    A control system for a rotary machine is provided. The rotary machine has at least one rotating member and at least one substantially stationary member positioned such that a clearance gap is defined between a portion of the rotating member and a portion of the substantially stationary member. The control system includes at least one clearance gap dimension measurement apparatus and at least one clearance gap adjustment assembly. The adjustment assembly is coupled in electronic data communication with the measurement apparatus. The control system is configured to process a clearance gap dimension signal and modulate the clearance gap dimension.

  17. Set-theoretic methods in control

    CERN Document Server

    Blanchini, Franco


    The second edition of this monograph describes the set-theoretic approach for the control and analysis of dynamic systems, both from a theoretical and practical standpoint.  This approach is linked to fundamental control problems, such as Lyapunov stability analysis and stabilization, optimal control, control under constraints, persistent disturbance rejection, and uncertain systems analysis and synthesis.  Completely self-contained, this book provides a solid foundation of mathematical techniques and applications, extensive references to the relevant literature, and numerous avenues for further theoretical study. All the material from the first edition has been updated to reflect the most recent developments in the field, and a new chapter on switching systems has been added.  Each chapter contains examples, case studies, and exercises to allow for a better understanding of theoretical concepts by practical application. The mathematical language is kept to the minimum level necessary for the adequate for...

  18. Idempotent Methods for Control and Games (United States)


    Seung Hak Han (UCSD, Expected Ph.D. date: 6/2014) – Minyi Ji (UCSD M.S. 2013) – Dr. Ali Oran (UCSD Ph.D. 2010, now Singapore-MIT Alliance for Res...Proc. IEEE CDC 2010, 2996–3001. [33] A. Oran and W.M. McEneaney, “Max-Plus Enabled Dynamic Program- ming for Sensor Platform Tasking”, Proc. 2010 ACC...Control and Op- tim., Vol. 43 (2004), 379–412. [47] William M. McEneaney, Ali Oran and Andrew Cavender, Value-Based Tasking Controllers for Sensing Assets

  19. A keyboard control method for loop measurement

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Z.W. [Universita Degli Studi di Roma La Sapienza (Italy)


    This paper describes a keyboard control mode based on the DEC VAX computer. The VAX Keyboard code can be found under running of a program was developed. During the loop measurement or multitask operation, it ables to be distinguished from a keyboard code to stop current operation or transfer to another operation while previous information can be held. The combining of this mode, the author successfully used one key control loop measurement for test Dual Input Memory module which is used in a rearrange Energy Trigger system for LEP 8 Bunch operation.

  20. Plaque control and oral hygiene methods

    LENUS (Irish Health Repository)

    Harrison, Peter


    The experimental gingivitis study of Löe et al.1 demonstrated a cause and effect relationship between plaque accumulation and gingival inflammation, and helped to establish plaque\\/biofilm as the primary risk factor for gingivitis. When healthy individuals withdrew oral hygiene efforts, gingival inflammation ensued within 21 days in all subjects. Once effective plaque removal was recommenced, clinical gingival health was quickly re-established – indicating that plaque-associated inflammation is modifiable by plaque control. As current consensus confirms that gingivitis and periodontitis may be viewed as a continuum of disease,2 the rationale for achieving effective plaque control is clear.

  1. Indigenous Control Methods for Parasites among Pastoralists ...

    African Journals Online (AJOL)


    the prices of veterinary drugs, compounded by their prolonged absences from offices of veterinary research ..... For example, ticks are controlled by oil from seed of Vitellaria paradoxawhich is mixed with table salt and .... urban Areas of Faisalabad (Pakistan) PhD Thesis, University of Agriculture,. Faisalabad, Pakistan.

  2. Augmented Lagrangian Method For Discretized Optimal Control ...

    African Journals Online (AJOL)

    In this paper, we are concerned with one-dimensional time invariant optimal control problem, whose objective function is quadratic and the dynamical system is a differential equation with initial condition .Since most real life problems are nonlinear and their analytical solutions are not readily available, we resolve to ...

  3. Apparatus and method for controlling autotroph cultivation

    Energy Technology Data Exchange (ETDEWEB)

    Fuxman, Adrian M; Tixier, Sebastien; Stewart, Gregory E; Haran, Frank M; Backstrom, Johan U; Gerbrandt, Kelsey


    A method includes receiving at least one measurement of a dissolved carbon dioxide concentration of a mixture of fluid containing an autotrophic organism. The method also includes determining an adjustment to one or more manipulated variables using the at least one measurement. The method further includes generating one or more signals to modify the one or more manipulated variables based on the determined adjustment. The one or more manipulated variables could include a carbon dioxide flow rate, an air flow rate, a water temperature, and an agitation level for the mixture. At least one model relates the dissolved carbon dioxide concentration to one or more manipulated variables, and the adjustment could be determined by using the at least one model to drive the dissolved carbon dioxide concentration to at least one target that optimize a goal function. The goal function could be to optimize biomass growth rate, nutrient removal and/or lipid production.

  4. Geometric Methods for Controlled Active Vision (United States)


    learning for neonate pain intensity assessment using digital imaging” (with B. Gholami and W. Haddad), IEEE Trans. Biomedical Engineering 57 (2010), pp...for cardiopulmonary management and intensive care unit sedation using expert systems,” (with B. Gholami, W. Haddad, J. Bailey), to appear in IEEE...stabilized visual closed-loop tracking” (with P. Karasev and P. Vela), Proceedings ACC, 2010. 55. ”Closed-loop control for intensive care unit sedation

  5. Quality control methods at a hospital. (United States)

    Canel, Cem; Mahar, Steve; Rosen, Drew; Taylor, John


    Healthcare providers need the information contained in patient records to provide high-quality services. To be effective, patient record assembly must be completed in a timely manner. This study aims to analyse the medical records assembly process for a hospital in Southeastern United States having difficulty meeting standard completion times established by the Joint Commission on the Accreditation of Healthcare Organization. Several quality improvement tools were used to evaluate and improve the assembly process. As a result of the study, a new procedure was implemented. Consequently, the hospital reduced the time required to assemble medical records, thereby improving efficiency and effectiveness. There are hopes to further improve the process. The study provides guidance on how statistical process control techniques can be applied to improve hospital services. The techniques employed can be used to analyze and improve any process. However, results are limited to improving medical record assembly processes at one particular hospital. Past studies considered the application of various statistical process control techniques for improving healthcare quality. The study extends research by employing process improvement efforts to understand and develop medical record assembly in a regional hospital via process flow diagramming and control charts.

  6. assessment of pests control methods and its perceived effect on ...

    African Journals Online (AJOL)


    May 31, 2006 ... Perceived Effect of Pests Control Methods on Agricultural Output in Kwara State, Nigeria 43 ... control method. According to Bueno (2011) who reported that biological control is the management and regular release of beneficial anthropods or .....

  7. Influence of discretization method on the digital control system performance

    Directory of Open Access Journals (Sweden)

    Futás József


    Full Text Available The design of control system can be divided into two steps. First the process or plant have to be convert into mathematical model form, so that its behavior can be analyzed. Then an appropriate controller have to be design in order to get the desired response of the controlled system. In the continuous time domain the system is represented by differential equations. Replacing a continuous system into discrete time form is always an approximation of the continuous system. The different discretization methods give different digital controller performance. The methods presented on the paper are Step Invariant or Zero Order Hold (ZOH Method, Matched Pole-Zero Method, Backward difference Method and Bilinear transformation. The above mentioned discretization methods are used in developing PI position controller of a dc motor. The motor model was converted by the ZOH method. The performances of the different methods are compared and the results are presented.

  8. Polynomial Method for PLL Controller Optimization

    Directory of Open Access Journals (Sweden)

    Tsung-Yu Chiou


    Full Text Available The Phase-Locked Loop (PLL is a key component of modern electronic communication and control systems. PLL is designed to extract signals from transmission channels. It plays an important role in systems where it is required to estimate the phase of a received signal, such as carrier tracking from global positioning system satellites. In order to robustly provide centimeter-level accuracy, it is crucial for the PLL to estimate the instantaneous phase of an incoming signal which is usually buried in random noise or some type of interference. This paper presents an approach that utilizes the recent development in the semi-definite programming and sum-of-squares field. A Lyapunov function will be searched as the certificate of the pull-in range of the PLL system. Moreover, a polynomial design procedure is proposed to further refine the controller parameters for system response away from the equilibrium point. Several simulation results as well as an experiment result are provided to show the effectiveness of this approach.

  9. Method for baghouse brown plume pollution control

    Energy Technology Data Exchange (ETDEWEB)

    Hooper, R.G.


    This patent describes an SO{sub x}/NO{sub x} air pollution control process employing a baghouse to simultaneously control particulate emissions. It comprises: introducing a sodium-based reagent into a stream of flue gas containing SO{sub x} and NO{sub x}; introducing urea as an additive into the flue gases; maintaining the reagent and the additive in contact with the flue gas to react the reagent with some of the SO{sub x} and NO{sub x} thereby reducing the concentration of the SO{sub x} and NO{sub x} in the flue gas; the additive, as compared to use of the reagent without the additive, increasing the percent SO{sub x} removal and the percent NO{sub x} removal by the reagent while suppressing conversion of NO to NO{sub 2} by the reagent to below about the visible brown plume threshold; and collecting the reacted reagent and additive in a baghouse.

  10. Nuclear reactor flow control method and apparatus (United States)

    Church, J.P.


    Method and apparatus for improving coolant flow in a nuclear reactor during accident as well as nominal conditions. The reactor has a plurality of fuel elements in sleeves and a plenum above the fuel and through which the sleeves penetrate. Holes are provided in the sleeve so that coolant from the plenum can enter the sleeve and cool the fuel. The number and size of the holes are varied from sleeve to sleeve with the number and size of holes being greater for sleeves toward the center of the core and less for sleeves toward the periphery of the core. Preferably the holes are all the same diameter and arranged in rows and columns, the rows starting from the bottom of every sleeve and fewer rows in peripheral sleeves and more rows in the central sleeves.

  11. Design Method of Active Disturbance Rejection Variable Structure Control System

    Directory of Open Access Journals (Sweden)

    Yun-jie Wu


    Full Text Available Based on lines cluster approaching theory and inspired by the traditional exponent reaching law method, a new control method, lines cluster approaching mode control (LCAMC method, is designed to improve the parameter simplicity and structure optimization of the control system. The design guidelines and mathematical proofs are also given. To further improve the tracking performance and the inhibition of the white noise, connect the active disturbance rejection control (ADRC method with the LCAMC method and create the extended state observer based lines cluster approaching mode control (ESO-LCAMC method. Taking traditional servo control system as example, two control schemes are constructed and two kinds of comparison are carried out. Computer simulation results show that LCAMC method, having better tracking performance than the traditional sliding mode control (SMC system, makes the servo system track command signal quickly and accurately in spite of the persistent equivalent disturbances and ESO-LCAMC method further reduces the tracking error and filters the white noise added on the system states. Simulation results verify the robust property and comprehensive performance of control schemes.

  12. Interactive robot control system and method of use (United States)

    Sanders, Adam M. (Inventor); Reiland, Matthew J. (Inventor); Abdallah, Muhammad E. (Inventor); Linn, Douglas Martin (Inventor); Platt, Robert (Inventor)


    A robotic system includes a robot having joints, actuators, and sensors, and a distributed controller. The controller includes command-level controller, embedded joint-level controllers each controlling a respective joint, and a joint coordination-level controller coordinating motion of the joints. A central data library (CDL) centralizes all control and feedback data, and a user interface displays a status of each joint, actuator, and sensor using the CDL. A parameterized action sequence has a hierarchy of linked events, and allows the control data to be modified in real time. A method of controlling the robot includes transmitting control data through the various levels of the controller, routing all control and feedback data to the CDL, and displaying status and operation of the robot using the CDL. The parameterized action sequences are generated for execution by the robot, and a hierarchy of linked events is created within the sequence.

  13. Control methods to improve non-linear HVAC system operations (United States)

    Phalak, Kaustubh Pradeep

    The change of weather conditions and occupancy schedules makes heating ventilating and air-conditioning (HVAC) systems heavily dynamic. The mass and thermal inertia, nonlinear characteristics and interactions in HVAC systems make the control more complicated. As a result, some conventional control methods often cannot provide desired control performance under variable operating conditions. The purpose of this study is to develop control methods to improve the control performance of HVAC systems. This study focuses on optimizing the airflow-pressure control method of air side economizers, identifying robust building pressurization controls, developing a control method to control outdoor air and building pressure in absence of flow and pressure sensors, stabilizing the cooling coil valve operation and, return fan speed control. The improvements can be achieved by identifying and selecting a method with relatively linear performance characteristics out of the available options, applying fans rather than dampers to control building pressure, and improving the controller's stability range using cascade control method. A steady state nonlinear network model, for an air handling unit (AHU), air distribution system and conditioned space, is applied to analyze the system control performance of air-side economizers and building pressurization. The study shows that traditional controls with completely interlinked outdoor air, recirculated air, relief air dampers have the best control performance. The decoupled relief damper control may result in negative building static pressure at lower outdoor airflow ratio and excessively positive building static pressure at higher outdoor airflow ratio. On the other hand, return fan speed control has a better controllability on building pressurization. In absence of flow and pressure sensors fixed interlinked damper and linear return fan speed tracking control can maintain constant outside air ratio and positive building pressure. The

  14. Inverse Kinematics of a New Quadruped Robot Control Method

    Directory of Open Access Journals (Sweden)

    Cai RunBin


    Full Text Available Design of redudant joints has been widely used in quadruped robots, so new kinds of techniques for sloving inverse kinematics are needed. In this paper we propose a new control method called Time-Pose control method and choose the enhanced extended jacobian matrix method for inverse kinematics. We deduce extended jacobian matrix method again so that it can be applicable for arbitrary joint length. It is argued that because the method can generate close joint angle path. With Time-Pose control method, such kind of inverse kinematics method has been used for trot gait on the flat ground. Simulations and experiments are performed, which prove the extended jacobian matrix method to be realizable for the quadruped robot.

  15. Control Methods for Energy Management of Refrigeration Systems

    DEFF Research Database (Denmark)

    Shafiei, Seyed Ehsan

    In this study, a high fidelity model for supermarket refrigeration systems is developed. The problem of energy management is investigated under two different demand-side management schemes: indirect and direct load control. The former is based on the electricity price incentive, and in the latter...... the consumption is directly managed by a third party based on a contract. For the indirect load control, we propose two different supervisory control approaches using model predictive control (MPC) technique to address the problem of electricity cost minimization. For the direct load control, three different...... control methods are proposed. The first method is the least complex one including decentralized proportional-integral control loops that can be applied to a general class of supermarket refrigeration systems. In the second method, an MPC is formulated for which a high fidelity model specific for each...

  16. A Robust Cooperated Control Method with Reinforcement Learning and Adaptive H∞ Control (United States)

    Obayashi, Masanao; Uchiyama, Shogo; Kuremoto, Takashi; Kobayashi, Kunikazu

    This study proposes a robust cooperated control method combining reinforcement learning with robust control to control the system. A remarkable characteristic of the reinforcement learning is that it doesn't require model formula, however, it doesn't guarantee the stability of the system. On the other hand, robust control system guarantees stability and robustness, however, it requires model formula. We employ both the actor-critic method which is a kind of reinforcement learning with minimal amount of computation to control continuous valued actions and the traditional robust control, that is, H∞ control. The proposed system was compared method with the conventional control method, that is, the actor-critic only used, through the computer simulation of controlling the angle and the position of a crane system, and the simulation result showed the effectiveness of the proposed method.

  17. A time-delayed method for controlling chaotic maps

    Energy Technology Data Exchange (ETDEWEB)

    Chen Maoyin [Department of Automation, Tsinghua University, Beijing 100084 (China)]. E-mail:; Zhou Donghua [Department of Automation, Tsinghua University, Beijing 100084 (China); Shang Yun [College of Mathematics and Information Science, Shaanxi Normal University, Xi' an 710062 (China)


    Combining the repetitive learning strategy and the optimality principle, this Letter proposes a time-delayed method to control chaotic maps. This method can effectively stabilize unstable periodic orbits within chaotic attractors in the sense of least mean square. Numerical simulations of some chaotic maps verify the effectiveness of this method.

  18. Force Feedback Control Method of Active Tuned Mass Damper

    Directory of Open Access Journals (Sweden)

    Xiuli Wang


    Full Text Available Active tuned mass dampers as vibration-control devices are widely used in many fields for their good stability and effectiveness. To improve the performance of such dampers, a control method based on force feedback is proposed. The method offers several advantages such as high-precision control and low-performance requirements for the actuator, as well as not needing additional compensators. The force feedback control strategy was designed based on direct-velocity feedback. The effectiveness of the method was verified in a single-degree-of-freedom system, and factors such as damping effect, required active force, actuator stroke, and power consumption of the damper were analyzed. Finally, a simulation study was performed by configuring a main complex elastic-vibration-damping system. The results show that the method provides effective control over modal resonances of multiple orders of the system and improves its dynamics performance.

  19. The frequency-independent control method for distributed generation systems

    DEFF Research Database (Denmark)

    Naderi, Siamak; Pouresmaeil, Edris; Gao, Wenzhong David


    are controlled in the synchronously rotating orthogonal . dq reference frame. The transformed variables are used in control of the voltage source inverter that connects DG to distribution network. Due to importance of distributed resources in modern power systems, development of new, practical, cost......-effective and simple control strategies is obligatory. The new control method of this paper does not need a Phase Locked Loop (PLL) in control circuit and has fast dynamic response in providing active and reactive power to nonlinear load. From extensive simulation results, high performance of this control strategy...

  20. Cooperative Control Method of Active and Semiactive Control: New Framework for Vibration Control


    Kazuhiko Hiramoto


    A new control design framework for vibration control, the cooperative control of active and semiactive control, is proposed in the paper. In the cooperative control, a structural system having both of an actuator and a semiactive control device, for example, MR damper and so forth, is defined as the control object. In the proposed control approach, the higher control performance is aimed by the cooperative control between the active control with the actuator and the semiactive control with th...

  1. Bifurcation-free design method of pulse energy converter controllers

    Energy Technology Data Exchange (ETDEWEB)

    Kolokolov, Yury [Institute of Applied Mathematics, Informatics and Control, Yugra State University, 16 Chekhova str., Khanty-Mansiysk 628012 (Russian Federation); Ustinov, Pavel [Department of Design and Technology of Electronic and Computer Systems, Orel State Technical University, 29 Naugorskoye Shosse, Orel 302020 (Russian Federation); CReSTIC, Universite de Reims Champagne-Ardenne, Moulin de la Housse, BP 1039, Reims Cedex 2, 51687 (France)], E-mail:; Essounbouli, Najib; Hamzaoui, Abdelaziz [CReSTIC, Universite de Reims Champagne-Ardenne, Moulin de la Housse, BP 1039, Reims Cedex 2, 51687 (France)


    In this paper, a design method of pulse energy converter (PEC) controllers is proposed. This method develops a classical frequency domain design, based on the small signal modeling, by means of an addition of a nonlinear dynamics analysis stage. The main idea of the proposed method consists in fact that the PEC controller, designed with an application of the small signal modeling, is tuned after with taking into the consideration an essentially nonlinear nature of the PEC that makes it possible to avoid bifurcation phenomena in the PEC dynamics at the design stage (bifurcation-free design). Also application of the proposed method allows an improvement of the designed controller performance. The application of this bifurcation-free design method is demonstrated on an example of the controller design of direct current-direct current (DC-DC) buck converter with an input electromagnetic interference filter.

  2. Singularly Perturbation Method Applied To Multivariable PID Controller Design

    Directory of Open Access Journals (Sweden)

    Mashitah Che Razali


    Full Text Available Proportional integral derivative (PID controllers are commonly used in process industries due to their simple structure and high reliability. Efficient tuning is one of the relevant issues of PID controller type. The tuning process always becomes a challenging matter especially for multivariable system and to obtain the best control tuning for different time scales system. This motivates the use of singularly perturbation method into the multivariable PID (MPID controller designs. In this work, wastewater treatment plant and Newell and Lee evaporator were considered as system case studies. Four MPID control strategies, Davison, Penttinen-Koivo, Maciejowski, and Combined methods, were applied into the systems. The singularly perturbation method based on Naidu and Jian Niu algorithms was applied into MPID control design. It was found that the singularly perturbed system obtained by Naidu method was able to maintain the system characteristic and hence was applied into the design of MPID controllers. The closed loop performance and process interactions were analyzed. It is observed that less computation time is required for singularly perturbed MPID controller compared to the conventional MPID controller. The closed loop performance shows good transient responses, low steady state error, and less process interaction when using singularly perturbed MPID controller.

  3. Design and Evaluation Methods for Underwater Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Chi, Lin


    This thesis on underwater control systems is written with the designer in mind, assuming that the reader has some knowledge of control theory. It can be used as a text for undergraduate students and engineers. To help readers better understand the system they will be working with, the thesis is organised in a stepwise way. The reader will gain basic knowledge about underwater operations, equipment and control systems. Then the reader will be able to follow the steps to develop a required control system for an underwater equipment by first understanding the characteristics of the design problem, customer requirement, functional requirement, and possible solution, and then to present a mathematical model of the control problem. Having developed the concept, the thesis guides the reader to develop evaluation criteria and different ways to make the decision. The thesis gives an overview of how to achieve a successful design rather than giving the techniques for detailed control system design. Chapter 1 describes underwater operations and systems. Chapter 2 discusses issues of underwater control systems and control methods. Chapter 3 deals with design method and control systems theory, focusing on human-centered control. Chapter 4 discusses methods used to evaluate and rank products, and chapter 5 applies the methods to an example. 113 refs., 115 figs., 80 tabs.

  4. A General Method for Designing Fractional Order PID Controller

    Directory of Open Access Journals (Sweden)

    Marzieh Safaei


    Full Text Available The idea of using fractional order calculus in control became apparent when this kind of calculus was accepted as a powerful tool in many applications. This resulted in a new generation of PID controller called fractional order PID Controller, named as Controller. controller is more flexible and provides a better response with larger stability region as compared with standard PID controller. This paper presents a simple and reliable method for finding the family of controllers. The required calculations are done in frequency domain based on frequency response of the system and the stability region is specified in the parameters space. This method can be used for time-delay systems and, more generally, for any system with no transfer function.

  5. Control and Optimization Methods for Electric Smart Grids

    CERN Document Server

    Ilić, Marija


    Control and Optimization Methods for Electric Smart Grids brings together leading experts in power, control and communication systems,and consolidates some of the most promising recent research in smart grid modeling,control and optimization in hopes of laying the foundation for future advances in this critical field of study. The contents comprise eighteen essays addressing wide varieties of control-theoretic problems for tomorrow’s power grid. Topics covered include: Control architectures for power system networks with large-scale penetration of renewable energy and plug-in vehicles Optimal demand response New modeling methods for electricity markets Control strategies for data centers Cyber-security Wide-area monitoring and control using synchronized phasor measurements. The authors present theoretical results supported by illustrative examples and practical case studies, making the material comprehensible to a wide audience. The results reflect the exponential transformation that today’s grid is going...

  6. The Robust Control Mixer Method for Reconfigurable Control Design By Using Model Matching Strategy

    DEFF Research Database (Denmark)

    Yang, Z.; Blanke, Mogens; Verhagen, M.


    This paper proposes a robust reconfigurable control synthesis method based on the combination of the control mixer method and robust H1 con- trol techniques through the model-matching strategy. The control mixer modules are extended from the conventional matrix-form into the LTI sys- tem form. By...... of one space robot arm system subjected to failures....

  7. Hydrothermal analysis in engineering using control volume finite element method

    CERN Document Server

    Sheikholeslami, Mohsen


    Control volume finite element methods (CVFEM) bridge the gap between finite difference and finite element methods, using the advantages of both methods for simulation of multi-physics problems in complex geometries. In Hydrothermal Analysis in Engineering Using Control Volume Finite Element Method, CVFEM is covered in detail and applied to key areas of thermal engineering. Examples, exercises, and extensive references are used to show the use of the technique to model key engineering problems such as heat transfer in nanofluids (to enhance performance and compactness of energy systems),

  8. Adaptive Cruise Control for a SMART Car : A Comparison Benchmark for MPC-PWA Control Methods

    NARCIS (Netherlands)

    Corona, D.; De Schutter, B.


    The design of an adaptive cruise controller for a SMART car, a type of small car, is proposed as a benchmark setup for several model predictive control methods for nonlinear and piecewise affine systems. Each of these methods has been already applied to specific case studies, different from method

  9. Numerical methods for optimal control problems with state constraints

    CERN Document Server

    Pytlak, Radosław


    While optimality conditions for optimal control problems with state constraints have been extensively investigated in the literature the results pertaining to numerical methods are relatively scarce. This book fills the gap by providing a family of new methods. Among others, a novel convergence analysis of optimal control algorithms is introduced. The analysis refers to the topology of relaxed controls only to a limited degree and makes little use of Lagrange multipliers corresponding to state constraints. This approach enables the author to provide global convergence analysis of first order and superlinearly convergent second order methods. Further, the implementation aspects of the methods developed in the book are presented and discussed. The results concerning ordinary differential equations are then extended to control problems described by differential-algebraic equations in a comprehensive way for the first time in the literature.

  10. Advanced Productivity Analysis Methods for Air Traffic Control Operations. (United States)


    This report gives a description of the Air Traffic Control (ATC) productivity analysis methods developed, implemented, and refined by the Stanford Research Institute (SRI) under the sponsorship of FAA and TSC. Two models are included in the productiv...

  11. Study of Inverted Pendulum Robot Using Fuzzy Servo Control Method

    Directory of Open Access Journals (Sweden)

    Dazhong Wang


    Full Text Available The inverted pendulum robot is a classical problem in controls. The inherit instabilities in the setup make it a natural target for a control system. Inverted pendulum robot is suitable to use for investigation and verification of various control methods for dynamic systems. Maintaining an equilibrium position of the pendulum pointing up is a challenge as this equilibrium position is unstable. As the inverted pendulum robot system is nonlinear it is well-suited to be controlled by fuzzy logic. In this paper, Lagrange method has been applied to develop the mathematical model of the system. The objective of the simulation to be shown using the fuzzy control method can stabilize the nonlinear system of inverted pendulum robot.

  12. Method for an energy-oriented production control


    Schultz, C.; Braunreuther, S.; Reinhart, G.


    Increasing energy costs as well as a growing awareness for sustainability are challenging companies to use energy more efficiently. Therefore, a company's production planning and control strategies have to be adapted. This paper presents a method for a short-term production control which aims to synchronize the energy demand in manufacturing with a limited energy supply. The method treats electric energy as a limited production capacity where load profiles for manufacturing are predetermined ...

  13. Process control and optimization with simple interval calculation method

    DEFF Research Database (Denmark)

    Pomerantsev, A.; Rodionova, O.; Høskuldsson, Agnar


    Methods of process control and optimization are presented and illustrated with a real world example. The optimization methods are based on the PLS block modeling as well as on the simple interval calculation methods of interval prediction and object status classification. It is proposed to employ...... for the quality improvement in the course of production. The latter is an active quality optimization, which takes into account the actual history of the process. The advocate approach is allied to the conventional method of multivariate statistical process control (MSPC) as it also employs the historical process...... the series of expanding PLS/SIC models in order to support the on-line process improvements. This method helps to predict the effect of planned actions on the product quality and thus enables passive quality control. We have also considered an optimization approach that proposes the correcting actions...

  14. Multivariate Statistical Process Control Process Monitoring Methods and Applications

    CERN Document Server

    Ge, Zhiqiang


      Given their key position in the process control industry, process monitoring techniques have been extensively investigated by industrial practitioners and academic control researchers. Multivariate statistical process control (MSPC) is one of the most popular data-based methods for process monitoring and is widely used in various industrial areas. Effective routines for process monitoring can help operators run industrial processes efficiently at the same time as maintaining high product quality. Multivariate Statistical Process Control reviews the developments and improvements that have been made to MSPC over the last decade, and goes on to propose a series of new MSPC-based approaches for complex process monitoring. These new methods are demonstrated in several case studies from the chemical, biological, and semiconductor industrial areas.   Control and process engineers, and academic researchers in the process monitoring, process control and fault detection and isolation (FDI) disciplines will be inter...

  15. Method of Controlling Steering of a Ground Vehicle (United States)

    Dawson, Andrew D. (Inventor); Bluethmann, William J. (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Guo, Raymond (Inventor); Atluri, Venkata Prasad (Inventor)


    A method of controlling steering of a vehicle through setting wheel angles of a plurality of modular electronic corner assemblies (eModules) is provided. The method includes receiving a driving mode selected from a mode selection menu. A position of a steering input device is determined in a master controller. A velocity of the vehicle is determined, in the master controller, when the determined position of the steering input device is near center. A drive mode request corresponding to the selected driving mode to the plurality of steering controllers is transmitted to the master controller. A required steering angle of each of the plurality of eModules is determined, in the master controller, as a function of the determined position of the steering input device, the determined velocity of the vehicle, and the selected first driving mode. The eModules are set to the respective determined steering angles.

  16. New Principles of Process Control in Geotechnics by Acoustic Methods

    Directory of Open Access Journals (Sweden)

    Leššo, I.


    Full Text Available The contribution describes the new solution of the control of rotary drilling process as some elementary process in geotechnics. The article presents the first results of research on the utilization of acoustic methods in identification process by optimal control of rotary drilling.

  17. Integrated Modeling and Intelligent Control Methods of Grinding Process

    Directory of Open Access Journals (Sweden)

    Jie-sheng Wang


    Full Text Available The grinding process is a typical complex nonlinear multivariable process with strongly coupling and large time delays. Based on the data-driven modeling theory, the integrated modeling and intelligent control method of grinding process is carried out in the paper, which includes the soft-sensor model of economic and technique indexes, the optimized set-point model utilizing case-based reasoning, and the self-tuning PID decoupling controller. For forecasting the key technology indicators (grinding granularity and mill discharge rate of grinding process, an adaptive soft-sensor modeling method based on wavelet neural network optimized by the improved shuffled frog leaping algorithm (ISFLA is proposed. Then, a set point optimization control strategy of grinding process based on case-based reasoning (CBR method is adopted to obtain the optimized velocity set-point of ore feed and pump water feed in the grinding process controlled loops. Finally, a self-tuning PID decoupling controller optimized is used to control the grinding process. Simulation results and industrial application experiments clearly show the feasibility and effectiveness of control methods and satisfy the real-time control requirements of the grinding process.

  18. Cost-Effectiveness of Aflatoxin Control Methods: Economic Incentives (United States)

    Multiple sectors in U.S. crop industries – growers, elevators, handlers/shellers, processors, distributors, and consumers – are affected by aflatoxin contamination of commodities, and have the potential to control it. Aflatoxin control methods at both preharvest and postharvest levels have been dev...

  19. Use of Modern Birth Control Methods Among Rural Communities in ...

    African Journals Online (AJOL)


    the high rate of population growth that it is presently experiencing. However, the adoption rate of the family planning method is still low 16, 17. About 70% of Nigeria's population live and work in the rural communities with a very high fertility rate 18. The introduction and acceptance of Modern Birth Control Methods (MBCM) ...

  20. assessment of pests control methods and its perceived effect on ...

    African Journals Online (AJOL)


    May 31, 2006 ... questionnaire was used to collect the data for the study. Descriptive statistics .... DD Force which is a very popular brand of organophosphates ... 100.0. Source: Field Survey 2016. Table 2:Awareness and Usage of different Types of Pest. Control Methods. Method. Yes. No. Farmers Awareness. Chemical.

  1. Control selection methods in recent case-control studies conducted as part of infectious disease outbreaks. (United States)

    Waldram, Alison; McKerr, Caoimhe; Gobin, Maya; Adak, Goutam; Stuart, James M; Cleary, Paul


    Successful investigation of national outbreaks of communicable disease relies on rapid identification of the source. Case-control methodologies are commonly used to achieve this. We assessed control selection methods used in recently published case-control studies for methodological and resource issues to determine if a standard approach could be identified. Neighbourhood controls were the most frequently used method in 53 studies of a range of different sizes, infections and settings. The most commonly used method of data collection was face to face interview. Control selection issues were identified in four areas: method of identification of controls, appropriateness of controls, ease of recruitment of controls, and resource requirements. Potential biases arising from the method of control selection were identified in half of the studies assessed. There is a need to develop new ways of selecting controls in a rapid, random and representative manner to improve the accuracy and timeliness of epidemiological investigations and maximise the effectiveness of public health interventions. Innovative methods such as prior recruitment of controls could improve timeliness and representativeness of control selection.

  2. Temperature Control of Autothermal Reformer System with Coefficient Diagram Method (United States)

    Srisiriwat, N.; Wutthithanyawat, C.


    The objective of this paper is to design the autothermal reformer (ATR) temperature control by using a coefficient diagram method (CDM). The adiabatic temperature is a main controlled variable of the ATR which is a combination of endothermic and exothermic reactions. The simulation results of control parameters were calculated to maintain the ATR reaction temperature by manipulating air feed flow rate. In this work, two strategies of ATR temperature controller system with and without the feed temperature control of a preheater unit are compared to investigate the appropriate controller system when the change of surrounding temperature is considered as a key disturbance. The results showed that by using the CDM, the stability and robustness for controlling the ATR temperature system were considered to offer the proper control parameters and the designed temperature control of ATR system gave a good performance to maintain the controlled variables and reject the disturbance. Moreover, the ATR control system design with the feed temperature controller can compensate the surrounding temperature better than that without the feed temperature control.

  3. Sound Zones: On Performance Prediction of Contrast Control Methods

    DEFF Research Database (Denmark)

    Møller, Martin Bo; Olsen, Martin


    Low frequency personal sound zones can be created by controlling the squared sound pressure in separate spatial confined control regions. Several methods have been proposed for realizing this scenario, with different constraints and performance. Extrapolating knowledge of the resulting acoustic...... separation from predicted results is a challenge as the obtainable performance relies on both physical setup and the chosen evaluation procedure. In this paper, the influence of the evaluation method is highlighted. Using the proposed evaluation four different control strategies for generation of low...

  4. A GPS-Based Decentralized Control Method for Islanded Microgrids

    DEFF Research Database (Denmark)

    Golsorkhi, Mohammad; Lu, Dylan; Guerrero, Josep M.


    , GPS timing technology is utilized to synchronize the DERs to a common reference frame, rotating at nominal frequency. In addition, an adaptive Q-f droop controller is introduced as a backup to ensure stable operation during GPS signal interruptions. In the context of the common reference frame, even......Coordinated control of distributed energy resources (DER) is essential for the operation of islanded microgrids (MGs). Conventionally, such coordination is achieved by drooping the frequency of the reference voltage versus active (or reactive) power. The conventional droop method ensures...... synchronized operation and even power sharing without any communication link. However, that method produces unwanted frequency fluctuations, which degrade the power quality. In order to improve the power quality of islanded MGs, a novel decentralized control method is proposed in this paper. In this method...

  5. A data driven control method for structure vibration suppression (United States)

    Xie, Yangmin; Wang, Chao; Shi, Hang; Shi, Junwei


    High radio-frequency space applications have motivated continuous research on vibration suppression of large space structures both in academia and industry. This paper introduces a novel data driven control method to suppress vibrations of flexible structures and experimentally validates the suppression performance. Unlike model-based control approaches, the data driven control method designs a controller directly from the input-output test data of the structure, without requiring parametric dynamics and hence free of system modeling. It utilizes the discrete frequency response via spectral analysis technique and formulates a non-convex optimization problem to obtain optimized controller parameters with a predefined controller structure. Such approach is then experimentally applied on an end-driving flexible beam-mass structure. The experiment results show that the presented method can achieve competitive disturbance rejections compared to a model-based mixed sensitivity controller under the same design criterion but with much less orders and design efforts, demonstrating the proposed data driven control is an effective approach for vibration suppression of flexible structures.

  6. Research advances in control methods of wearable walking assist robots

    Directory of Open Access Journals (Sweden)

    Xia ZHANG


    Full Text Available As the proportion of the elderly in China increases, the need for robotic assist walking is growing. The assisted-as-needed (AAN property of a wearable walking assist robot matches a user’s biological need and improves the flexibility, appetency and friendliness of a mechanical system. To realize AAN walking and aiming at realizing master/slave flexible assist, a new hybrid control method consisting of hip joint control based on central pattern generators and knee joint impedance structured control is proposed. The adaptation of a robot's master/slave motion mode to a user's physical function, the continuous switching method for knee joint impedance structured control and its stability, and the AAN effect of the Hybrid control theory are studied, which provides a new thought for the development of wearable walking assist robots.

  7. Spline-based self-controlled case series method. (United States)

    Ghebremichael-Weldeselassie, Yonas; Whitaker, Heather J; Farrington, C Paddy


    The self-controlled case series (SCCS) method is an alternative to study designs such as cohort and case control methods and is used to investigate potential associations between the timing of vaccine or other drug exposures and adverse events. It requires information only on cases, individuals who have experienced the adverse event at least once, and automatically controls all fixed confounding variables that could modify the true association between exposure and adverse event. Time-varying confounders such as age, on the other hand, are not automatically controlled and must be allowed for explicitly. The original SCCS method used step functions to represent risk periods (windows of exposed time) and age effects. Hence, exposure risk periods and/or age groups have to be prespecified a priori, but a poor choice of group boundaries may lead to biased estimates. In this paper, we propose a nonparametric SCCS method in which both age and exposure effects are represented by spline functions at the same time. To avoid a numerical integration of the product of these two spline functions in the likelihood function of the SCCS method, we defined the first, second, and third integrals of I-splines based on the definition of integrals of M-splines. Simulation studies showed that the new method performs well. This new method is applied to data on pediatric vaccines. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  8. A method for closed loop automatic tuning of PID controllers

    Directory of Open Access Journals (Sweden)

    Tor S. Schei


    Full Text Available A simple method for the automatic tuning of PID controllers in closed loop is proposed. A limit cycle is generated through a nonlinear feedback path from the process output to the controller reference signal. The frequency of this oscillation is above the crossover frequency and below the critical frequency of the loop transfer function. The amplitude and frequency of the oscillation are estimated and the control parameters are adjusted iteratively such that the closed loop transfer function from the controller reference to the process output attains a specified amplitude at the oscillation frequency.

  9. Control Method for Variable Speed Wind Turbines to Support Temporary Primary Frequency Control

    DEFF Research Database (Denmark)

    Wang, Haijiao; Chen, Zhe; Jiang, Quanyuan


    This paper develops a control method for variable speed wind turbines (VSWTs) to support temporary primary frequency control of power system. The control method contains two parts: (1) up-regulate support control when a frequency drop event occurs; (2) down-regulate support control when a frequency...... rise event occurs. The up-regulate support is achieved by adaptively utilizing the wind energy curtailed by the pitch control and the kinetic energy stored in the rotating mass of the turbine blades. The down-regulate support is achieved by the pitch control. Furthermore, the up- and down......-regulate capabilities are quantified under different wind speeds. Finally, the whole control method is verified in a test power system established in MATLAB/Simulink, which contains a wind farm of 180 VSWTs....

  10. Battery charging control methods, electric vehicle charging methods, battery charging apparatuses and rechargeable battery systems (United States)

    Tuffner, Francis K [Richland, WA; Kintner-Meyer, Michael C. W. [Richland, WA; Hammerstrom, Donald J [West Richland, WA; Pratt, Richard M [Richland, WA


    Battery charging control methods, electric vehicle charging methods, battery charging apparatuses and rechargeable battery systems. According to one aspect, a battery charging control method includes accessing information regarding a presence of at least one of a surplus and a deficiency of electrical energy upon an electrical power distribution system at a plurality of different moments in time, and using the information, controlling an adjustment of an amount of the electrical energy provided from the electrical power distribution system to a rechargeable battery to charge the rechargeable battery.

  11. Fault-Tolerant Process Control Methods and Applications

    CERN Document Server

    Mhaskar, Prashant; Christofides, Panagiotis D


    Fault-Tolerant Process Control focuses on the development of general, yet practical, methods for the design of advanced fault-tolerant control systems; these ensure an efficient fault detection and a timely response to enhance fault recovery, prevent faults from propagating or developing into total failures, and reduce the risk of safety hazards. To this end, methods are presented for the design of advanced fault-tolerant control systems for chemical processes which explicitly deal with actuator/controller failures and sensor faults and data losses. Specifically, the book puts forward: ·         a framework for  detection, isolation and diagnosis of actuator and sensor faults for nonlinear systems; ·         controller reconfiguration and safe-parking-based fault-handling methodologies; ·         integrated-data- and model-based fault-detection and isolation and fault-tolerant control methods; ·         methods for handling sensor faults and data losses; and ·      ...

  12. Method and apparatus for automatic control of a humanoid robot (United States)

    Abdallah, Muhammad E (Inventor); Platt, Robert (Inventor); Wampler, II, Charles W. (Inventor); Reiland, Matthew J (Inventor); Sanders, Adam M (Inventor)


    A robotic system includes a humanoid robot having a plurality of joints adapted for force control with respect to an object acted upon by the robot, a graphical user interface (GUI) for receiving an input signal from a user, and a controller. The GUI provides the user with intuitive programming access to the controller. The controller controls the joints using an impedance-based control framework, which provides object level, end-effector level, and/or joint space-level control of the robot in response to the input signal. A method for controlling the robotic system includes receiving the input signal via the GUI, e.g., a desired force, and then processing the input signal using a host machine to control the joints via an impedance-based control framework. The framework provides object level, end-effector level, and/or joint space-level control of the robot, and allows for functional-based GUI to simplify implementation of a myriad of operating modes.

  13. Comparison of methods for solids retention time determination and control (United States)

    Balbierz, Piotr; Knap, Marta


    Solids retention time (SRT) is the basic and most important process parameter in design, operation and control of activated sludge (AS) systems, especially with nitrification and biological nutrient removal. However, determination of SRT at the full-scale wastewater treatment plant (WWTP) may not be straightforward and the significance of proper SRT control is often underestimated by plant operators, which may lead to severe operational problems, including complete nitrification failure. This paper presents different methods for SRT determination and control, including simple hydraulic method and phosphorous mass balance method. The comparison is based on an extended data set from a large WWTP in south-west Poland, both in stable and transient operational conditions. The results of the comparison show that during stable operational conditions, all the SRT determination methods give similar results, thus the simple hydraulic method can be applied during standard operation, even at small WWTPs, which lack laboratory facilities. Hydraulic method is based on continuous on-line flowrate measurements, therefore it gives opportunity to implement an algorithm to automatically control SRT and sludge wastage from the system.

  14. Delayless acceleration measurement method for motion control applications

    Energy Technology Data Exchange (ETDEWEB)

    Vaeliviita, S.; Ovaska, S.J. [Helsinki University of Technology, Otaniemi (Finland). Institute of Intelligent Power Electronics


    Delayless and accurate sensing of angular acceleration can improve the performance of motion control in motor drives. Acceleration control is, however, seldom implemented in practical drive systems due to prohibitively high costs or unsatisfactory results of most acceleration measurement methods. In this paper we propose an efficient and accurate acceleration measurement method based on direct differentiation of the corresponding velocity signal. Polynomial predictive filtering is used to smooth the resulting noisy signal without delay. This type of prediction is justified by noticing that a low-degree polynomial can usually be fitted into the primary acceleration curve. No additional hardware is required to implement the procedure if the velocity signal is already available. The performance of the acceleration measurement method is evaluated by applying it to a demanding motion control application. (orig.) 12 refs.

  15. Comparison of DUPIC fuel composition heterogeneity control methods

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hang Bok; Ko, Won Il [Korea Atomic Energy Research Institute, Taejon (Korea)


    A method to reduce the fuel composition heterogeneity effect on the core performance parameters has been studied for the DUPIC fuel which is made of spent pressurized water reactor (PWR) fuels by a dry refabrication process. This study focuses on the reactivity control method which uses either slightly enriched, depleted, or natural uranium to minimize the cost rise effect on the manufacturing of DUPIC fuel, when adjusting the excess reactivity of the spent PWR fuel. In order to reduce the variation of isotopic composition of the DUPIC fuel, the inter-assembly mixing operation was taken three times. Then, three options have been considered: reactivity control by slightly enriched and depleted uranium, reactivity control by natural uranium for high reactivity spent PWR fuels, and reactivity control by natural uranium for linear reactivity spent PWR fuels. The results of this study have shown that the reactivity of DUPIC fuel can be tightly controlled with the minimum amount of fresh uranium feed. For the reactivity control by slightly enriched and depleted uranium, all the spent PWR fuels can be utilized as the DUPIC fuel and the fraction of fresh uranium feed is 3.4% on an average. For the reactivity control by natural uranium, about 88% of spent PWR fuel can be utilized as the DUPIC fuel when the linear reactivity spent PWR fuels are used, and the amount of natural uranium feed needed to control the DUPIC fuel reactivity is negligible. 13 refs., 6 figs., 16 tabs. (Author)

  16. Optimization and control methods in industrial engineering and construction

    CERN Document Server

    Wang, Xiangyu


    This book presents recent advances in optimization and control methods with applications to industrial engineering and construction management. It consists of 15 chapters authored by recognized experts in a variety of fields including control and operation research, industrial engineering, and project management. Topics include numerical methods in unconstrained optimization, robust optimal control problems, set splitting problems, optimum confidence interval analysis, a monitoring networks optimization survey, distributed fault detection, nonferrous industrial optimization approaches, neural networks in traffic flows, economic scheduling of CCHP systems, a project scheduling optimization survey, lean and agile construction project management, practical construction projects in Hong Kong, dynamic project management, production control in PC4P, and target contracts optimization.   The book offers a valuable reference work for scientists, engineers, researchers and practitioners in industrial engineering and c...

  17. Adaptive decoupled power control method for inverter connected DG

    DEFF Research Database (Denmark)

    Sun, Xiaofeng; Tian, Yanjun; Chen, Zhe


    The integration of renewable energy technology is making the power distribution system more flexible, but also introducing challenges for traditional technology. With the nature of intermittent and less inertial, renewable energy-based generations need effective control methods to cooperate...... an adaptive droop control method based on online evaluation of power decouple matrix for inverter connected distributed generations in distribution system. Traditional decoupled power control is simply based on line impedance parameter, but the load characteristics also cause the power coupling, and alter...... with other devices, such as storage, loads and the utility grid. The widely used power frequency (P–f) droop control is based on the precondition of inductive line impedance, but the low-voltage system is mainly resistive, and also the different load character needs to be considered. This study presents...

  18. The Control of Asymmetric Rolling Missiles Based on Improved Trajectory Linearization Control Method

    Directory of Open Access Journals (Sweden)

    Huadong Sun


    Full Text Available According to motion characteristic of an asymmetric rolling missile with damage fin, a three-channel controlled model is established. The controller which is used to realize non-linear tracking and decoupling control of the roll and angle motion is introduced based on an improved trajector y linearization control method. The improved method is composed of the classic trajectory linearization control method and a compensation control law. The classic trajectory linearization control method is implemented in the time-scale separation principle. The Lipschitz non-linear state observer systematically obtained by solving the linear matrix inequality approach is provided to estimate state variables and unknown parameters, and then the compensation control law utilizing the estimated unknown parameters improves the TLC method. Simulation experiments show that the adaptive decoupling control ensure tracking performance, and the robustness and accuracy of missile attitude control are ensured under the condition of the system parameters uncertainty, random observation noise and external disturbance caused by damage fin.

  19. A control method for voltage balancing in modular multilevel converters

    DEFF Research Database (Denmark)

    Deng, Fujin; Chen, Zhe


    The modular multilevel converter (MMC) is attractive for medium- or high-power applications because of the advantages of its high modularity, availability, and high power quality. The voltage balancing of the floating capacitors in the cascaded submodules of the MMC is a key issue. In this paper......, a voltage-balancing control method is proposed. This method uses the phase-shifted carrier-based pulsewidth modulation scheme to control high-frequency current components for capacitor voltage balancing in the MMC without measuring the arm currents. Simulations and experimental studies of the MMC were...

  20. The simplex method for nonlinear sliding mode control

    Directory of Open Access Journals (Sweden)

    Bartolini G.


    Full Text Available General nonlinear control systems described by ordinary differential equations with a prescribed sliding manifold are considered. A method of designing a feedback control law such that the state variable fulfills the sliding condition in finite time is based on the construction of a suitable simplex of vectors in the tangent space of the manifold. The convergence of the method is proved under an obtuse angle condition and a way to build the required simplex is indicated. An example of engineering interest is presented.

  1. A method for the control of multigrasp myoelectric prosthetic hands. (United States)

    Dalley, Skyler Ashton; Varol, Huseyin Atakan; Goldfarb, Michael


    This paper presents the design and preliminary experimental validation of a multigrasp myoelectric controller. The described method enables direct and proportional control of multigrasp prosthetic hand motion among nine characteristic postures using two surface electromyography electrodes. To assess the efficacy of the control method, five nonamputee subjects utilized the multigrasp myoelectric controller to command the motion of a virtual prosthesis between random sequences of target hand postures in a series of experimental trials. For comparison, the same subjects also utilized a data glove, worn on their native hand, to command the motion of the virtual prosthesis for similar sequences of target postures during each trial. The time required to transition from posture to posture and the percentage of correctly completed transitions were evaluated to characterize the ability to control the virtual prosthesis using each method. The average overall transition times across all subjects were found to be 1.49 and 0.81 s for the multigrasp myoelectric controller and the native hand, respectively. The average transition completion rates for both were found to be the same (99.2%). Supplemental videos demonstrate the virtual prosthesis experiments, as well as a preliminary hardware implementation.

  2. Analysis of droop control method in an autonomous microgrid

    Directory of Open Access Journals (Sweden)

    Amir Khaledian


    Full Text Available In this paper an analytical approach is conducted to evaluate the droop control method in an islanding microgrid. Droop control is the key solution for sharing the demand power between generators in autonomous microgrids where there is no support from the electricity distribution grid. In the paper, three important load types are investigated to verify the droop control performance. First, coupling of active power and reactive power is considered in the microgrid and a new method is proposed to facilitate separate control of powers. In the proposed method the effects of droop gains on decoupling of active power and reactive power control, voltage regulation, power oscillation and system stability are studied. In the second load type study, by applying the different types of faults, induction motor characteristics are observed. By simulation results it is shown that the fault intensity and duration will determine how the microgrid attains to fast frequency convergence and how fast protection system operation can improve system stability. In the third case, imbalanced nonlinear load is studied in the microgrid and the influences of embedded controllers on harmonic distortion, system balance and voltage regulation are observed.

  3. Optimal pulse design in quantum control: a unified computational method. (United States)

    Li, Jr-Shin; Ruths, Justin; Yu, Tsyr-Yan; Arthanari, Haribabu; Wagner, Gerhard


    Many key aspects of control of quantum systems involve manipulating a large quantum ensemble exhibiting variation in the value of parameters characterizing the system dynamics. Developing electromagnetic pulses to produce a desired evolution in the presence of such variation is a fundamental and challenging problem in this research area. We present such robust pulse designs as an optimal control problem of a continuum of bilinear systems with a common control function. We map this control problem of infinite dimension to a problem of polynomial approximation employing tools from geometric control theory. We then adopt this new notion and develop a unified computational method for optimal pulse design using ideas from pseudospectral approximations, by which a continuous-time optimal control problem of pulse design can be discretized to a constrained optimization problem with spectral accuracy. Furthermore, this is a highly flexible and efficient numerical method that requires low order of discretization and yields inherently smooth solutions. We demonstrate this method by designing effective broadband π/2 and π pulses with reduced rf energy and pulse duration, which show significant sensitivity enhancement at the edge of the spectrum over conventional pulses in 1D and 2D NMR spectroscopy experiments.

  4. Nanosilicon properties, synthesis, applications, methods of analysis and control

    CERN Document Server

    Ischenko, Anatoly A; Aslalnov, Leonid A


    Nanosilicon: Properties, Synthesis, Applications, Methods of Analysis and Control examines the latest developments on the physics and chemistry of nanosilicon. The book focuses on methods for producing nanosilicon, its electronic and optical properties, research methods to characterize its spectral and structural properties, and its possible applications. The first part of the book covers the basic properties of semiconductors, including causes of the size dependence of the properties, structural and electronic properties, and physical characteristics of the various forms of silicon. It presents theoretical and experimental research results as well as examples of porous silicon and quantum dots. The second part discusses the synthesis of nanosilicon, modification of the surface of nanoparticles, and properties of the resulting particles. The authors give special attention to the photoluminescence of silicon nanoparticles. The third part describes methods used for studying and controlling the structure and pro...

  5. Comparison of three control methods for an autonomous vehicle (United States)

    Deshpande, Anup; Mathur, Kovid; Hall, Ernest


    The desirability and challenge of developing a completely autonomous vehicle and the rising need for more efficient use of energy by automobiles motivate this research- a study for an optimum solution to computer control of energy efficient vehicles. The purpose of this paper is to compare three control methods - mechanical, hydraulic and electric that have been used to convert an experimental all terrain vehicle to drive by wire which would eventually act as a test bed for conducting research on various technologies for autonomous operation. Computer control of basic operations in a vehicle namely steering, braking and speed control have been implemented and will be described in this paper. The output from a 3 axis motion controller is used for this purpose. The motion controller is interfaced with a software program using WSDK (Windows Servo Design Kit) as an intermediate tuning layer for tuning and parameter settings in autonomous operation. The software program is developed in C++. The voltage signal sent to the motion controller can be varied through the control program for desired results in controlling the steering motor, activating the hydraulic brakes and varying the vehicle's speed. The vehicle has been tested for its basic functionality which includes testing of street legal operations and also a 1000 mile test while running in a hybrid mode. The vehicle has also been tested for control when it is interfaced with devices such as a keyboard, joystick and sensors under full autonomous operation. The vehicle is currently being tested in various safety studies and is being used as a test bed for experiments in control courses and research studies. The significance of this research is in providing a greater understanding of conventional driving controls and the possibility of improving automobile safety by removing human error in control of a motor vehicle.

  6. Brain-controlled body movement assistance devices and methods

    Energy Technology Data Exchange (ETDEWEB)

    Leuthardt, Eric C.; Love, Lonnie J.; Coker, Rob; Moran, Daniel W.


    Methods, devices, systems, and apparatus, including computer programs encoded on a computer storage medium, for brain-controlled body movement assistance devices. In one aspect, a device includes a brain-controlled body movement assistance device with a brain-computer interface (BCI) component adapted to be mounted to a user, a body movement assistance component operably connected to the BCI component and adapted to be worn by the user, and a feedback mechanism provided in connection with at least one of the BCI component and the body movement assistance component, the feedback mechanism being configured to output information relating to a usage session of the brain-controlled body movement assistance device.

  7. Active vibration control using state space LQG and internal model control methods

    DEFF Research Database (Denmark)

    Mørkholt, Jakob; Elliott, S.J.


    Two ways of designing discrete time robust H2-controllers for feedback broadband active vibration control are compared through computer simulations. The methods are based on different models of disturbance and plant transfer functions, but yield controllers with identical properties. Two simple...... ways of introducing robustness into the H2-design are compared, and finally an efficient way of designing a practical IIR-controller is proposed....

  8. Agent-Based Decentralized Control Method for Islanded Microgrids

    DEFF Research Database (Denmark)

    Li, Qiang; Chen, Feixiong; Chen, Minyou


    In this paper, an agent-based decentralized control model for islanded microgrids is proposed, which consists of a two-layer control structure. The bottom layer is the electrical distribution microgrid, while the top layer is the communication network composed of agents. An agent is regarded...... is processed according to control laws, agents adjust the production of distributed generators to which they connect. The main contributions of this paper are (i) an agent-based model for decentralized secondary control is introduced and the rules to establish the communication network are given; (ii......) a systematic method is presented, which can be used to derive a set of control laws for agents from any given communication network, where only local information is needed. Furthermore, it has been seen that the output power supplied by distributed generators satisfies the load demand in the microgrid, when...

  9. Method and System for Active Noise Control of Tiltrotor Aircraft (United States)

    Betzina, Mark D. (Inventor); Nguyen, Khanh Q. (Inventor)


    Methods and systems for reducing noise generated by rotating blades of a tiltrotor aircraft. A rotor-blade pitch angle associated with the tiltrotor aircraft can be controlled utilizing a swashplate connected to rotating blades of the tiltrotor aircraft. One or more Higher Harmonic Control (HHC) signals can be transmitted and input to a swashplate control actuator associated with the swashplate. A particular blade pitch oscillation (e.g., four cycles per revolution) is there-after produced in a rotating frame of reference associated with the rotating blades in response to input of an HHC signal to the swashplate control actuator associated with the swashplate to thereby reduce noise associated with the rotating blades of the tiltrotor aircraft. The HHC signal can be transmitted and input to the swashplate control actuator to reduce noise of the tiltrotor aircraft in response to a user input utilizing an open-loop configuration.

  10. Overview On Alternative Asbestos Control Method Research: Alternative Methods To Demolition (United States)

    The Alternative Asbestos Control Method (AACM) is an experimental approach to building demolition. Unlike the NESHAP method, the AACM allows some regulated asbestos-containing material to remain in the building and a surfactant-water solution is used to suppress asbestos fibers ...

  11. Homotopy Method in Applied Problems of the Anisotropic Control Theory

    Directory of Open Access Journals (Sweden)

    A. V. Yurchenkov


    Full Text Available The work describes a numerical method of solving the specific systems of matrix equations emerging in the tasks of the modern theory of control. Since the standard tasks of the control theory demand making a number of assumptions about input effect, at the slightest non-compliance the synthesized laws of control become either extremely inefficient or too much power consumable. As opposed to these assumptions, while setting the problem of anisotropic theory of control, it is necessary to know only the average anisotropy level of the input sequence. Consequently, anisotropic regulators are always found to be no worse than standard ones. In synthesis of anisotropic regulator a rather complex algorithm of its construction is the only difficulty. When considering a problem of ensuring robust quality of the control object in case of the structured uncertainty there is a need to solve a system of four connected Riccati equations, equation of a special form, and Lyapunov equation. To solve it by standard methods of convex optimization is impossible. The work shows how the standard mean square Gaussian regulator allows us to obtain as anisotropic regulator to meet requirements of robust quality when there is an imperfect knowledge of mathematical model of object of control, a lack of exact stochastic characteristics of the input control, parametrical uncertainty, etc. The article offers an algorithm based on the homotopy method with the Newtonian iterations to solve a problem of anisotropic optimization. It presents a computing procedure to reach the objective. Using a task of searching the anisotropic regulator to minimize the maximum value of anisotropic norm of transfer function of the control object, the article describes required matrix derivatives of stabilizing solutions of Riccati equations, equation of a special form, and Lyapunov equation. Properties of Kronecker product and matrix differentiation with respect to matrix are given.

  12. Cost versus effectiveness of different birth control methods. (United States)

    Trussell, T J


    Abstract This paper is an empirical investigation of the mix of birth control methods that would be, allocationally efficient in a real population. Current British resource cost and effectiveness data for each method are presented in order to test the prevalent opinion that expenditure on abortion is allocationally inefficient. Even when abortion resources are valued to give a conservatively high cost, however, this opinion is not upheld. When both quantifiable resource costs and effectiveness are plotted for each method, some linear combination of coitus interruptus, and coitus interruptus with all failures terminated by abortion is shown to be the allocationally efficient frontier.

  13. A method for unified optimization of systems and controllers

    DEFF Research Database (Denmark)

    Abildgaard, Ole


    A unified method for solving control system optimization problems is suggested. All system matrices are allowed to be functions of the design variables. The method makes use of an implementation of a sequential quadratic programming algorithm (NLPQL) for solution of general constrained nonlinear...... programming problems. It is shown how to compute the gradients of the objective function and the constraint functions imposing eigenvalue constraints. In an example it is demonstrated how the method can solve a high-dimensional problem, where the initial condition covariance assumption is used to ensure...

  14. Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices (United States)

    Chassin, David P.; Donnelly, Matthew K.; Dagle, Jeffery E.


    Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices are described. In one aspect, an electrical power distribution control method includes providing electrical energy from an electrical power distribution system, applying the electrical energy to a load, providing a plurality of different values for a threshold at a plurality of moments in time and corresponding to an electrical characteristic of the electrical energy, and adjusting an amount of the electrical energy applied to the load responsive to an electrical characteristic of the electrical energy triggering one of the values of the threshold at the respective moment in time.


    Cawley, W.E.


    A method and apparatus are described for controlling an overmoderated nuclear reactor containing columns of fuel elements aligned in a plurality of coolant tubes in a stream of coolant water. The invention includes means for adjusting the distance between halves of the fuel element column to vary the relative proportion of fuel and moderator at the center of the reactor. (AEC)

  16. Algorithms and Methods for High-Performance Model Predictive Control

    DEFF Research Database (Denmark)

    Frison, Gianluca

    The goal of this thesis is to investigate algorithms and methods to reduce the solution time of solvers for Model Predictive Control (MPC). The thesis is accompanied with an open-source toolbox for High-Performance implementation of solvers for MPC (HPMPC), that contains the source code of all...

  17. Automated Model Fit Method for Diesel Engine Control Development

    NARCIS (Netherlands)

    Seykens, X.; Willems, F.P.T.; Kuijpers, B.; Rietjens, C.


    This paper presents an automated fit for a control-oriented physics-based diesel engine combustion model. This method is based on the combination of a dedicated measurement procedure and structured approach to fit the required combustion model parameters. Only a data set is required that is

  18. Assessment of Digital Access Control Methods Used by Selected ...

    African Journals Online (AJOL)

    Assessment of Digital Access Control Methods Used by Selected Academic Libraries in South-West Nigeria. ... information professionals with the knowledge that would enable them establish an effective strategy to protect e-resources from such abuses as plagiarism, piracy and infringement of intellectual property rights.

  19. Indigenous methods of controlling pests among rice farmers in Patigi ...

    African Journals Online (AJOL)

    Indigenous methods of controlling pests among rice farmers in Patigi Local Government Area of Kwara state, Nigeria. G.B Adesiji, I Ogunlade, I Ogunlade, O Bolarin, O Bolarin, R.S Adisa, R.S Adisa, L.L Adefalu, L.L Adefalu, M.K Raji ...

  20. Numerical analysis using state space method for vibration control of ...

    African Journals Online (AJOL)


    Numerical analysis using state space method for vibration control of car seat by employing passive and semi active dampers. Udit S. Kotagi1, G.U. Raju1, V.B. Patil2, Krishnaraja G. Kodancha1*. 1Department of Mechanical Engineering, B.V. Bhoomaraddi College of Engineering & Technology, Hubli, Karnataka, INDIA.

  1. Assessment of pests control methods and its perceived effect on ...

    African Journals Online (AJOL)

    The study examined the usage of chemical and biological pests control methods among the farmers in Kwara State, Nigeria. A three-stage random sampling technique was used to select 120 respondents. A well structure questionnaire was used to collect the data for the study. Descriptive statistics and partial correlation ...

  2. Influence of weed control methods, poultry manure and planting ...

    African Journals Online (AJOL)

    Field trials were conducted during the rainy seasons (2012 and 2013) at the Research Farm of Institute for Agricultural Research, Samaru Zaria and College of Agriculture and Animal Science, Mando Kaduna, in the Northern Guinea Savannah Zone of Nigeria, to determine the Influence of weed control methods, poultry ...

  3. The Effects of Different Weed Control Methods on Weed Infestation ...

    African Journals Online (AJOL)

    A field experiment was conducted during the 2012 and 2013 rainy season at the Kwara State University Teaching and Research Farm located in Malete. The aim was to determine the effect(s) of different weed control methods on Weed infestation, growth and yield of soybeans (variety TGX 1448 – 2E). The experiment ...

  4. Economic assessment of tillage systems and weed control methods ...

    African Journals Online (AJOL)

    This study was conducted to appraise the economics of different land preparation systems and weed management options in maize cultivation in three ecological zones (Ikenne, Ibadan and Ilorin) of southwestern Nigeria. Four tillage systems as main treatments and six weed control methods as sub-treatments were ...

  5. A decentralized control method for direct smart grid control of refrigeration systems

    DEFF Research Database (Denmark)

    Shafiei, Seyed Ehsan; Izadi-Zamanabadi, Roozbeh; Rasmussen, Henrik


    . No model information is required in this method. The temperature limits/constraints are respected. A novel adaptive saturation filter is also proposed to increase the system flexibility in storing and delivering the energy. The proposed control strategy is applied to a simulation benchmark that fairly......A decentralized control method is proposed to govern the electrical power consumption of supermarket refrigeration systems (SRS) for demand-side management in the smart grid. The control structure is designed in a supervisory level to provide desired set-points for distributed level controllers...... simulates the CO2 booster system of a supermarket refrigeration....

  6. Bayesian Variable Selection Methods for Matched Case-Control Studies. (United States)

    Asafu-Adjei, Josephine; Mahlet, G Tadesse; Coull, Brent; Balasubramanian, Raji; Lev, Michael; Schwamm, Lee; Betensky, Rebecca


    Matched case-control designs are currently used in many biomedical applications. To ensure high efficiency and statistical power in identifying features that best discriminate cases from controls, it is important to account for the use of matched designs. However, in the setting of high dimensional data, few variable selection methods account for matching. Bayesian approaches to variable selection have several advantages, including the fact that such approaches visit a wider range of model subsets. In this paper, we propose a variable selection method to account for case-control matching in a Bayesian context and apply it using simulation studies, a matched brain imaging study conducted at Massachusetts General Hospital, and a matched cardiovascular biomarker study conducted by the High Risk Plaque Initiative.

  7. Navigation Algorithm Using Fuzzy Control Method in Mobile Robotics

    Directory of Open Access Journals (Sweden)

    Cviklovič Vladimír


    Full Text Available The issue of navigation methods is being continuously developed globally. The aim of this article is to test the fuzzy control algorithm for track finding in mobile robotics. The concept of an autonomous mobile robot EN20 has been designed to test its behaviour. The odometry navigation method was used. The benefits of fuzzy control are in the evidence of mobile robot’s behaviour. These benefits are obtained when more physical variables on the base of more input variables are controlled at the same time. In our case, there are two input variables - heading angle and distance, and two output variables - the angular velocity of the left and right wheel. The autonomous mobile robot is moving with human logic.


    Directory of Open Access Journals (Sweden)



    Full Text Available In the article there were presented chosen method associated with statistical control of production processes. Mainly focused on control cards and Pareto‐Lorenz analysis. Showed method were implemented to analysis production process stability of hearing aids in X company (the brand name don’t give because date of production is secret. Researches were made few months after new assembly lines starts‐up. Main aim of researches was defects types identification occurred in production process and determine the scale of effect. Finally received results were satisfactory, i.e. despite of occurred errors, control cards analysis showed that production process of BTE‐type (Behind‐The‐Ear hearing aids was stable.

  9. Method for rudder roll stabilization control by maintaining ship speed

    Directory of Open Access Journals (Sweden)

    LIU Zhiquan


    Full Text Available A ship navigating on the surface of the water may experience greater resistance, adversely affect-ing its speed and leading to energy loss. The added resistance of surface ships in both still water and waves are investigated, and the computation method of total speed loss is presented. An autopilot system is intro-duced to constrain the speed loss, and course keeping and rudder roll stabilization sliding mode control laws are proposed according to a compact control strategy. The two working conditions of "heading" and "heading plus anti-roll" are discussed, including roll stabilization, heading error, speed maintenance and rudder abrasion. The results show that the speed can be effectively maintained using this method, and from a commercial point of view, the fin-rudder roll stabilization control is not recommended for vessels equipped with both fins and rudders.

  10. Remote Voltage Control Using the Holomorphic Embedding Load Flow Method

    DEFF Research Database (Denmark)

    Liu, Chengxi; Qin, Nan; Sun, Kai


    This paper proposes a new remote voltage control approach based on the non-iterative holomorphic embedding load flow method (HELM). A participation factor matrix is applied together with the HELM to distribute reactive power injections among multiple remote reactive power resources such that the ......This paper proposes a new remote voltage control approach based on the non-iterative holomorphic embedding load flow method (HELM). A participation factor matrix is applied together with the HELM to distribute reactive power injections among multiple remote reactive power resources...... such that the approach can remotely control the voltage magnitudes of desired buses. The proposed approach is compared with a conventional Newton-Raphson approach by study cases on the IEEE New England 39-bus system. The results show that the proposed approach achieves a larger convergence region....

  11. Analog neural network control method proposed for use in a backup satellite control mode

    Energy Technology Data Exchange (ETDEWEB)

    Frigo, J.R.; Tilden, M.W.


    The authors propose to use an analog neural network controller implemented in hardware, independent of the active control system, for use in a satellite backup control mode. The controller uses coarse sun sensor inputs. The field of view of the sensors activate the neural controller, creating an analog dead band with respect to the direction of the sun on each axis. This network controls the orientation of the vehicle toward the sunlight to ensure adequate power for the system. The attitude of the spacecraft is stabilized with respect to the ambient magnetic field on orbit. This paper develops a model of the controller using real-time coarse sun sensor data and a dynamic model of a prototype system based on a satellite system. The simulation results and the feasibility of this control method for use in a satellite backup control mode are discussed.

  12. [A new control method for Haemonchus contortus: FAMACHA]. (United States)

    Selver, Melih


    FAMACHA is a method that has been developed against Haemonchus contortus which causes anemia in sheep and goats especially in tropical and subtropical areas. The basic principle of the method is the detection of the color changes in the mucous membrane of the eye that is caused by anemia. According to the FAMACHA Anemia Guide, (FAG), the mucous membranes of the eyes of animals are inspected for color differences at two or three week intervals. The criteria are used for treating the animals. Thus FAG provides practical diagnosis and treatment of animals that are actually affected by H. contortus. Avoiding unnecessary treatment prevents the formation of drug resistance. The method is effective only if it is used with an effective Trichostrongylidae control program. The FAMACHA method can be tested in Turkey where H. contortus is a problem; especially in mild and rainy areas. Furthermore, the method maybe modified for other parasites causing anemia.

  13. a Novel Sideway Stability Control Method for Bipedal Walking Robot (United States)

    Jo, H. Siswoyo; Mir-Nasiri, N.


    This paper presents a novel sensing and balancing method for bipedal walking robot. The proposed method involves the design of semi-rigid ankle joint to facilitate the responsive and accurate measurement of the sideway (sagittal) instability of the walking robot. The use of double balancing mass and the developed control algorithms provide a constant sideway stability of the robot while it walks in forward direction. The smooth legs trajectory planning then can be implemented successfully regardless of the robot sideway stability condition. The developed method is able to decouple the walking algorithms from the robot stability issues. Furthermore, the use of two different masses for the balancing helps to improve response time and efficiency of the balancing system. In this paper, the proposed method is tested on the simplified model of a robot balancing on its single leg and the feasibility of the method is confirmed by the simulation results obtained with MATLAB Simulink tools.

  14. Statistical disclosure control for microdata methods and applications in R

    CERN Document Server

    Templ, Matthias


    This book on statistical disclosure control presents the theory, applications and software implementation of the traditional approach to (micro)data anonymization, including data perturbation methods, disclosure risk, data utility, information loss and methods for simulating synthetic data. Introducing readers to the R packages sdcMicro and simPop, the book also features numerous examples and exercises with solutions, as well as case studies with real-world data, accompanied by the underlying R code to allow readers to reproduce all results. The demand for and volume of data from surveys, registers or other sources containing sensible information on persons or enterprises have increased significantly over the last several years. At the same time, privacy protection principles and regulations have imposed restrictions on the access and use of individual data. Proper and secure microdata dissemination calls for the application of statistical disclosure control methods to the data before release. This book is in...


    Directory of Open Access Journals (Sweden)



    Full Text Available The most important way to control the pests is to not use chemicals, preventing the environmental pollution in the different ecosystems. We proposed to study and apply the unchemical methods according to ecological pest management, to control some pesticide resistant pests. The research has been oriented to the physical methods: the use of the light radiation reflected by different materials (supports, directly applied on the hostplant leaves or on the ground, which remove the insects from the damaged zone; the use of visual traps (coloured panels and coloured plates, which attract and capture the insects. The researches were carried out in 2002, with five experiences organised in two ecosystems (orchard and mountain grazing. The both categories of methods were very effective.

  16. Deformation compatibility control for engineering structures methods and applications

    CERN Document Server

    Zhu, Hanhua; Chen, Mengchong; Deng, Jianliang


    This book presents essential methods of deformation compatibility control, and explicitly addresses the implied conditions on the methods’ deformation compatibility. Consequently, these conditions can be considered in engineering structure design, while the conditions on stable equilibrium can be taken into account in the design method. Thus, the designed deformation and the actual deformation of the respective structure are approximately identical, guaranteeing both the flexibility of the construction material in force transmission and the equilibrium of force in the structure. Though equilibrium theory in engineering structures has been extensively studied, there has been comparatively little research on compatibility. In the limited researches available, the topics are primarily the theories and assumptions on the deformation compatibility, while few systematic works focus on the mechanical theoretical principles and methods of deformation compatibility control. As such, the flexibility of the constructi...

  17. Flux-weakening control methods for hybrid excitation synchronous motor

    Directory of Open Access Journals (Sweden)

    Mingming Huang


    Full Text Available The hybrid excitation synchronous motor (HESM, which aim at combining the advantages of permanent magnet motor and wound excitation motor, have the characteristics of low-speed high-torque hill climbing and wide speed range. Firstly, a new kind of HESM is presented in the paper, and its structure and mathematical model are illustrated. Then, based on a space voltage vector control, a novel flux-weakening method for speed adjustment in the high speed region is presented. The unique feature of the proposed control method is that the HESM driving system keeps the q-axis back-EMF components invariable during the flux-weakening operation process. Moreover, a copper loss minimization algorithm is adopted to reduce the copper loss of the HESM in the high speed region. Lastly, the proposed method is validated by the simulation and the experimental results.

  18. Jerk Minimization Method for Vibration Control in Buildings (United States)

    Abatan, Ayo O.; Yao, Leummim


    In many vibration minimization control problems for high rise buildings subject to strong earthquake loads, the emphasis has been on a combination of minimizing the displacement, the velocity and the acceleration of the motion of the building. In most cases, the accelerations that are involved are not necessarily large but the change in them (jerk) are abrupt. These changes in magnitude or direction are responsible for most building damage and also create discomfort like motion sickness for inhabitants of these structures because of the element of surprise. We propose a method of minimizing also the jerk which is the sudden change in acceleration or the derivative of the acceleration using classical linear quadratic optimal controls. This was done through the introduction of a quadratic performance index involving the cost due to the jerk; a special change of variable; and using the jerk as a control variable. The values of the optimal control are obtained using the Riccati equation.

  19. Concepts and Methods in Fault-tolerant Control

    DEFF Research Database (Denmark)

    Blanke, Mogens; Staroswiecly, M.; Wu, N.E.


    in an intelligent way. The aim is to prevent that simple faults develop into serious failure and hence increase plant availability and reduce the risk of safety hazards. Fault-tolerant control merges several disciplines into a common framework to achieve these goals. The desired features are obtained through on-line......Faults in automated processes will often cause undesired reactions and shut-down of a controlled plant, and the consequences could be damage to technical parts of the plant, to personnel or the environment. Fault-tolerant control combines diagnosis with control methods to handle faults...... fault diagnosis, automatic condition assessment and calculation of appropriate remedial actions to avoid certain consequences of a fault. The envelope of the possible remedial actions is very wide. Sometimes, simple could be achieved by replacing a measurement from a faulty sensor by an estimate. In yet...

  20. The Quadrotor Dynamic Modeling and Indoor Target Tracking Control Method

    Directory of Open Access Journals (Sweden)

    Dewei Zhang


    Full Text Available A reliable nonlinear dynamic model of the quadrotor is presented. The nonlinear dynamic model includes actuator dynamic and aerodynamic effect. Since the rotors run near a constant hovering speed, the dynamic model is simplified at hovering operating point. Based on the simplified nonlinear dynamic model, the PID controllers with feedback linearization and feedforward control are proposed using the backstepping method. These controllers are used to control both the attitude and position of the quadrotor. A fully custom quadrotor is developed to verify the correctness of the dynamic model and control algorithms. The attitude of the quadrotor is measured by inertia measurement unit (IMU. The position of the quadrotor in a GPS-denied environment, especially indoor environment, is estimated from the downward camera and ultrasonic sensor measurements. The validity and effectiveness of the proposed dynamic model and control algorithms are demonstrated by experimental results. It is shown that the vehicle achieves robust vision-based hovering and moving target tracking control.

  1. A fabrication method of microneedle molds with controlled microstructures. (United States)

    Wang, Qi Lei; Zhu, Dan Dan; Chen, Yang; Guo, Xin Dong


    Microneedle (MN) offers an attractive, painless and minimally invasive approach for transdermal drug delivery. Polymer microneedles are normally fabricated by using the micromolding method employing a MN mold, which is suitable for mass production due to high production efficiency and repeat-using of the mold. Most of the MN molds are prepared by pouring sylgard polymer over a MN master to make an inverse one after curing, which is limited in optimizing or controlling the MN structures and failing to keep the sharpness of MNs. In this work we describe a fabrication method of MN mold with controlled microstructures, which is meaningful for the fabrication of polymer MNs with different geometries. Laser micro-machining method was employed to drill on the surface of PDMS sheets to obtain MN molds. In the fabrication process, the microstructures of MN molds are precisely controlled by changing laser parameters and imported patterns. The MNs prepared from these molds are sharp enough to penetrate the skin. This scalable MN mold fabrication method is helpful for future applications of MNs. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Methods for invasive species control are transferable across invaded areas. (United States)

    Haramura, Takashi; Crossland, Michael R; Takeuchi, Hirohiko; Shine, Richard


    Cane Toads (Rhinella marina) are invasive pests in many parts of the world, including the Japanese island of Ishigaki. Extensive research in Australia has identified promising new methods for control, but also has shown that toads exhibit geographic variation in many traits (suggesting that methods developed in one location may not work in another). Can the approaches developed in Australia play a useful role for controlling this invasive species in Japan? Our experimental trials on Ishigaki Island suggest that these new methods can be successfully applied to Japan. First, Cane Toad embryos exposed to chemical cues of conspecific tadpoles exhibited a reduction in viability (subsequent growth and development). This response appears to be species-specific, with native frog embryos not being affected by exposure to cues from toad tadpoles, and Cane Toad embryos not being affected by exposure to cues from native frog tadpoles. Second, Cane Toad tadpoles were attracted to traps containing water from conspecific eggs, and toxin from adult conspecifics. Third, adult Cane Toads were attracted to acoustic cues of calling males, with sex differences in rates of attraction to specific versions of a synthetic call (males were attracted to choruses whereas females were attracted to low-frequency calls). Our results suggest that the methods developed by Australian researchers are applicable to controlling invasive Cane Toads in Japan.

  3. Compound control method of neutral point voltage of three level NPC inverter based on the vector method of virtual space and hysteresis control (United States)

    Yang, Fengping; Xiao, Fangfei


    Current control methods include hardware control and software control corresponding to the inherent unbalance problem of neutral point voltage in three level NPC inverter. The hardware control is rarely used due to its high cost. In this paper, a new compound control method has been presented based on the vector method of virtual space and traditional hysteresis control of neutral point voltage, which can make up the shortcoming of the virtual control without the feedback control system of neutral point voltage and the blind area of hysteresis control and control the deviation and wave of neutral point voltage. The accuracy of this method has been demonstrated by simulation.

  4. Advanced methods for displays and remote control of robots. (United States)

    Eliav, Ami; Lavie, Talia; Parmet, Yisrael; Stern, Helman; Edan, Yael


    An in-depth evaluation of the usability and situation awareness performance of different displays and destination controls of robots are presented. In two experiments we evaluate the way information is presented to the operator and assess different means for controlling the robot. Our study compares three types of displays: a "blocks" display, a HUD (head-up display), and a radar display, and two types of controls: touch screen and hand gestures. The HUD demonstrated better performance when compared to the blocks display and was perceived to have greater usability compared to the radar display. The HUD was also found to be more useful when the operation of the robot was more difficult, i.e., when using the hand-gesture method. The experiments also pointed to the importance of using a wide viewing angle to minimize distortion and for easier coping with the difficulties of locating objects in the field of view margins. The touch screen was found to be superior in terms of both objective performance and its perceived usability. No differences were found between the displays and the controllers in terms of situation awareness. This research sheds light on the preferred display type and controlling method for operating robots from a distance, making it easier to cope with the challenges of operating such systems. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  5. Evaluation of two methods in controlling dental treatment water contamination. (United States)

    Bansal, Ritu; Puttaiah, Raghunath; Harris, Robert; Reddy, Anil


    Dental unit water systems are contaminated with biofilms that amplify bacterial counts in dental treatment water in excess of a million colony forming units per milliliter (cfu/ml). The Centers for Disease Control and Prevention and the American Dental Association have agreed that the maximum allowable contamination of dental treatment water not exceed 500 cfu/ml. This study was conducted to evaluate two protocols in controlling contamination of dental unit water systems and dental treatment water. Both methods used an antimicrobial self-dissolving chlorine dioxide (ClO₂) tablet at a high concentration (50 ppm) to shock the dental unit water system biofilms initially followed by periodic exposure. To treat dental treatment source water for patient care, 3 parts per million (ppm) ClO₂ in municipal/tap water was compared to use of a citrus botanical extract dissolved in municipal water. Heterotrophic microbial counts of effluent water and laser scanning confocal microscopy were performed to evaluate effects of the two treatments. Results from this study indicated that both treatments were effective in controlling biofilm contamination and reducing heterotrophic plate counts water system and effects of low-grade chemicals used on composite bonding to dentin and enamel is warranted before translation from efficacy studies to common clinical use. This study provides evidence-based information of using two methods of controlling dental treatment water contamination. The study was conducted in a clinical practice setting in an active dental clinic and the results are meaningful to a clinician who is interested in providing safe dental treatment water for patient care. Dental waterline biofilms, Dental treatment water contamination control, Chlorine dioxide, Emulsifiers, Heterotrophic plate counts, Laser scanning confocal microscopy. How to cite this article: Bansal R, Puttaiah R, Harris R, Reddy A. Evaluation of Two Methods in Controlling Dental Treatment Water

  6. The covering method for the solution of terminal control problem

    Directory of Open Access Journals (Sweden)

    V. N. Chetverikov


    Full Text Available A new method for solving the terminal control problem for dynamical systems is formulated. This problem is to determine a program trajectory and a program control that takes the system from a given initial state to a given final state. The method is based on the addition of equations with control derivative to the source system and reformulation of the problem in the boundary value problem for the augmented system E. Additional equations must be chosen so as to satisfy the following conditions. There is a surjective map (covering from the phase space E to the phase space of some dynamical system Y. The covering takes solutions of E to solutions of Y. Boundary conditions in the final moment are mapped to the boundary conditions on the solutions of Y. Any solution of Y satisfies the boundary conditions in the initial moment. Then the solution of the terminal control problem is as the solution of two Cauchy problems for dynamical systems E and Y. Augmented system E satisfying mentioned properties is called r-closure of the terminal control problem. It is shown that this approach generalizes the well-known method for solving the terminal control problem for flat systems. A flat system is a system whose solutions are uniquely determined by a certain set of functions of time (flat output. The mentioned well-known method is based on polynomial dependence of flat output of time and do not take into account constraints on the system.It is proved that for an arbitrary flat system r-closure can be chosen any determined system of ordinary differential equations of the corresponding order. It is showed how to construct a covering with the above-mentioned properties using the general solution of this system. The properties of the covering are proved only locally, i.e. when the initial time is close to the final time, and the initial conditions are close the final conditions. But this covering may be applicable to other terminal problems with the same final

  7. Methods of detecting and controlling mucoid Pseudomonas biofilm production (United States)

    Yu, Hongwei D. (Inventor); Qiu, Dongru (Inventor)


    Compositions and methods for detecting and controlling the conversion to mucoidy in Pseudomonas aeruginosa are disclosed. The present invention provides for detecting the switch from nonmucoid to mucoid state of P. aeruginosa by measuring mucE expression or MucE protein levels. The interaction between MucE and AlgW controls the switch to mucoidy in wild type P. aeruginosa. Also disclosed is an alginate biosynthesis heterologous expression system for use in screening candidate substances that inhibit conversion to mucoidy.

  8. ISS Contingency Attitude Control Recovery Method for Loss of Automatic Thruster Control (United States)

    Bedrossian, Nazareth; Bhatt, Sagar; Alaniz, Abran; McCants, Edward; Nguyen, Louis; Chamitoff, Greg


    In this paper, the attitude control issues associated with International Space Station (ISS) loss of automatic thruster control capability are discussed and methods for attitude control recovery are presented. This scenario was experienced recently during Shuttle mission STS-117 and ISS Stage 13A in June 2007 when the Russian GN&C computers, which command the ISS thrusters, failed. Without automatic propulsive attitude control, the ISS would not be able to regain attitude control after the Orbiter undocked. The core issues associated with recovering long-term attitude control using CMGs are described as well as the systems engineering analysis to identify recovery options. It is shown that the recovery method can be separated into a procedure for rate damping to a safe harbor gravity gradient stable orientation and a capability to maneuver the vehicle to the necessary initial conditions for long term attitude hold. A manual control option using Soyuz and Progress vehicle thrusters is investigated for rate damping and maneuvers. The issues with implementing such an option are presented and the key issue of closed-loop stability is addressed. A new non-propulsive alternative to thruster control, Zero Propellant Maneuver (ZPM) attitude control method is introduced and its rate damping and maneuver performance evaluated. It is shown that ZPM can meet the tight attitude and rate error tolerances needed for long term attitude control. A combination of manual thruster rate damping to a safe harbor attitude followed by a ZPM to Stage long term attitude control orientation was selected by the Anomaly Resolution Team as the alternate attitude control method for such a contingency.

  9. Method of electron emission control in RF guns

    CERN Document Server

    Khodak, I V


    The electron emission control method for a RF gun is considered.According to the main idea of the method,the additional resonance system is created in a cathode region where the RF field strength could be varied using the external pulse equipment. The additional resonance system is composed of a coaxial cavity coupled with a RF gun cylindrical cavity via an axial hole. Computed results of radiofrequency and electrodynamic performances of such a two-cavity system and results of the RF gun model pilot study are presented in. Results of particle dynamics simulation are described.

  10. A quality control method for nuclear instrumentation and control systems based on software safety prediction (United States)

    Son, Han Seong; Seong, Poong Hyun


    In the case of safety-related applications like nuclear instrumentation and control (NI&C), safety-oriented quality control is required. The objective of this paper is to present a software safety classification method as a safety-oriented quality control tool. Based on this method, we predict the risk (and thus safety) of software items that are at the core of NI&C systems. Then we classify the software items according to the degree of the risk. The method can be used earlier than at the detailed design phase. Furthermore, the method can also be used in all the development phases without major changes. The proposed method seeks to utilize the measures that can be obtained from the safety analysis and requirements analysis. Using the measures proved to be desirable in a few aspects. The authors have introduced fuzzy approximate reasoning to the classification method because experts' knowledge covers the vague frontiers between good quality and bad quality with linguistic uncertainty and fuzziness. Fuzzy Colored Petri Net (FCPN) is introduced in order to offer a formal framework for the classification method and facilitate the knowledge representation, modification, or verification. Through the proposed quality control method, high-quality NI&C systems can be developed effectively and used safely.

  11. The Effect of Laser Treatment as a Weed Control Method

    DEFF Research Database (Denmark)

    Mathiassen, Solvejg K; Bak, Thomas; Christensen, Svend


    A laser beam directed towards weeds can be an efficient weed control method as an alternative to herbicides. Lasers may deliver high-density energy to selected plant material, raising the temperature of the water in the plant cells and thereby stop or delay the growth. A commercial use of lasers ...... (exposure time and spot size of the laser beam). The experiment also showed a significant difference between two wavelengths. In order to improve the performance and to validate the efficacy on a broader spectrum of weed species, further research and development is needed.......A laser beam directed towards weeds can be an efficient weed control method as an alternative to herbicides. Lasers may deliver high-density energy to selected plant material, raising the temperature of the water in the plant cells and thereby stop or delay the growth. A commercial use of lasers...


    Directory of Open Access Journals (Sweden)

    Mircea Sofonea


    Full Text Available We consider a multivalued equation of the form Ay + F(y = fin a real Hilbert space, where A is a linear operator and F represents the (Clarke subdifferential of some function. We prove existence and uniqueness results of the solution by using the control variational method. The main idea in this method is to minimize the energy functional associated to the nonlinear equation by arguments of optimal control theory. Then we consider a general mathematical model describing the contact between a linearly elastic body and an obstacle which leads to a variational formulation as above, for the displacement field. We apply the abstract existence and uniqueness results to prove the unique weak solvability of the corresponding contact problem. Finally, we present examples of contact and friction laws for which our results work.

  13. Legislation, standards and methods for mercury emissions control

    Energy Technology Data Exchange (ETDEWEB)



    Mercury is an element of growing global concern. The United Nations Environment Programme plans to finalise and ratify a new global legally-binding convention on mercury by 2013. Canada already has legislation on mercury emissions from coal-fired utilities and the USA has recently released the new Mercury and Air Toxics Standard. Although other countries may not have mercury-specific legislation as such, many have legislation which results in significant co-benefit mercury reduction due to the installation of effective flue-gas cleaning technologies. This report reviews the current situation and trends in mercury emission legislation and, where possible, discusses the actions that will be taken under proposed or impending standards globally and regionally. The report also reviews the methods currently applied for mercury control and for mercury emission measurement with emphasis on the methodologies most appropriate for compliance. Examples of the methods of mercury control currently deployed in the USA, Canada and elsewhere are included.

  14. A Novel Method to Predict Circulation Control Noise (United States)


    anemom-:Jtry. Hotwire anemometry operates on the principle relating the thermal loss of a heated resistance sensor to the convective effects of the...Circulation Control Noise 5b. GRANT NUMBER N00014-12-1-0544 Sc. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Sd. PROJECT NUMBER Robert Reger, Adam Nickels...maneuverability. However, with CC comes additional noise sources. A method involving estimation of the velocity, surface pressure, and far-field

  15. Method of technological control of proportional electromagnets for control systems of their production (United States)

    Lankin, A. M.; Lankin, M. V.; Lankina, M. Y.


    This article describes the algorithm of the method of technological control of proportional solenoids to control their production process. An important element in the process of production of proportional solenoids is to identify deviations from the nominal mode of its occurrence. This situation shows the relevance of developing a method of technological control of proportional solenoids providing information on process control in a short time. The proposed algorithm consists of four steps: measuring the dynamic characteristics of the magnetization of electromagnet testing, the use of principal component analysis to reduce the dimension of the analyzed information, the classification of products by the condition and sub-standards, the definition of the numerical values of the manufacturing process variations using a calibration method. This approach allows us to determine the type and the degree of impairment of the mode of the process that will lead to effective management of the production process of the electromagnetic actuators.

  16. Apparatus and method for gas turbine active combustion control system (United States)

    Umeh, Chukwueloka (Inventor); Kammer, Leonardo C. (Inventor); Shah, Minesh (Inventor); Fortin, Jeffrey B. (Inventor); Knobloch, Aaron (Inventor); Myers, William J. (Inventor); Mancini, Alfred Albert (Inventor)


    An Active Combustion Control System and method provides for monitoring combustor pressure and modulating fuel to a gas turbine combustor to prevent combustion dynamics and/or flame extinguishments. The system includes an actuator, wherein the actuator periodically injects pulsed fuel into the combustor. The apparatus also includes a sensor connected to the combustion chamber down stream from an inlet, where the sensor generates a signal detecting the pressure oscillations in the combustor. The apparatus controls the actuator in response to the sensor. The apparatus prompts the actuator to periodically inject pulsed fuel into the combustor at a predetermined sympathetic frequency and magnitude, thereby controlling the amplitude of the pressure oscillations in the combustor by modulating the natural oscillations.

  17. A novel stiffness control method for series elastic actuator (United States)

    Lin, Guangmo; Zhao, Xingang; Han, Jianda


    Compliance plays an important role in human-robot cooperation. However, fixed compliance, or fixed stiffness, is difficult to meet the growing needs of human machine collaboration. As a result, the robot actuator is demanded to be able to adjust its stiffness. This paper presents a stiffness control scheme for a single DOF series elastic actuator (SEA) with a linear spring mounted in series in the mechanism. In this proposed method, the output angle of the spring is measured and used to calculate the input angle of the spring, thus the equivalent stiffness of the robot actuator revealed to the human operator can be rendered in accordance to the desired stiffness. Since the techniques used in this method only involve the position information of the system, there is no need to install an expensive force/torque sensor on the actuator. Further, the force/torque produced by the actuator can be estimated by simply multiplying the deformation angle of the spring and its constant stiffness coefficient. The analysis of the stiffness controller is provided. Then a simulation that emulates a human operates the SEA while the stiffness controller is running is carried out and the results also validate the proposed method.

  18. Parallel efficient rate control methods for JPEG 2000 (United States)

    Martínez-del-Amor, Miguel Á.; Bruns, Volker; Sparenberg, Heiko


    Since the introduction of JPEG 2000, several rate control methods have been proposed. Among them, post-compression rate-distortion optimization (PCRD-Opt) is the most widely used, and the one recommended by the standard. The approach followed by this method is to first compress the entire image split in code blocks, and subsequently, optimally truncate the set of generated bit streams according to the maximum target bit rate constraint. The literature proposes various strategies on how to estimate ahead of time where a block will get truncated in order to stop the execution prematurely and save time. However, none of them have been defined bearing in mind a parallel implementation. Today, multi-core and many-core architectures are becoming popular for JPEG 2000 codecs implementations. Therefore, in this paper, we analyze how some techniques for efficient rate control can be deployed in GPUs. In order to do that, the design of our GPU-based codec is extended, allowing stopping the process at a given point. This extension also harnesses a higher level of parallelism on the GPU, leading to up to 40% of speedup with 4K test material on a Titan X. In a second step, three selected rate control methods are adapted and implemented in our parallel encoder. A comparison is then carried out, and used to select the best candidate to be deployed in a GPU encoder, which gave an extra 40% of speedup in those situations where it was really employed.

  19. Quality control methods for Aedes albopictus sterile male production.

    Directory of Open Access Journals (Sweden)

    Fabrizio Balestrino


    Full Text Available The capacity of the released sterile males to survive, disperse, compete with wild males and inseminate wild females is an essential prerequisite to be evaluated in any area-wide integrated pest management (AW-IPM programs including a sterile insect release method. Adequate quality control tests supported by standardized procedures need to be developed to measure these parameters and to identify and correct potential inappropriate rearing or handling methods affecting the overall male quality. In this study, we report results on the creation and validation of the first quality control devices designed to infer the survival and mating capacity of radio-sterilized Aedes albopictus males through the observation of their flight capacity under restricted conditions (flight organ device and after stress treatment (aspirator device. Results obtained consistently indicate comparable flight capacity and quality parameters between untreated and 35 Gy irradiated males while a negative impact was observed with higher radiation doses at all observation time performed. The male flight capacity registered with the proposed quality control devices can be successfully employed, with different predictive capacities and response time, to infer the adult male quality. These simple and cost-effective tools provide a valuable method to detect and amend potentially sub-standard procedures in the sterile male production line and hence contribute to maintaining optimal quality and field performance of the mosquitoes being released.

  20. Osmotic shock as alternative method to control Acanthaster planci

    Directory of Open Access Journals (Sweden)

    Jairo Rivera-Posada


    Full Text Available Objective: To test six osmotic stressors as alternative methods to control Acanthaster planci (A. planci outbreaks by exploiting their incapacity to tolerate drastic changes in osmolarity. Finding more effective ways to control A. planci outbreaks is one of the most immediate and effective ways by which to reverse rapid declines in the abundance of live coral cover in the Indo-Pacific. Methods: A total of 10 mL of each of the following chemicals: sodium chloride, ethylenediaminetetraacetic acid, sodium carbonate, sodium cholate, sodium deoxycholate, urea and mannitol were injected into individual healthy sea stars to examine which chemicals induced disease and death. Results: Four out of six chemicals used in this study induced disease. Sodium chloride, sodium cholate, sodium deoxycholate and ethylenediaminetetraacetic acid are capable of inducing death in injected sea stars offering an alternative option to control A. planci outbreaks. Conclusions: Hyperosmotic stress is a viable alternative to control A. planci outbreaks as massive cell death results when acute hypertonicity exceeds a certain level.

  1. Evaluating methods for controlling depth perception in stereoscopic cinematography (United States)

    Sun, Geng; Holliman, Nick


    Existing stereoscopic imaging algorithms can create static stereoscopic images with perceived depth control function to ensure a compelling 3D viewing experience without visual discomfort. However, current algorithms do not normally support standard Cinematic Storytelling techniques. These techniques, such as object movement, camera motion, and zooming, can result in dynamic scene depth change within and between a series of frames (shots) in stereoscopic cinematography. In this study, we empirically evaluate the following three types of stereoscopic imaging approaches that aim to address this problem. (1) Real-Eye Configuration: set camera separation equal to the nominal human eye interpupillary distance. The perceived depth on the display is identical to the scene depth without any distortion. (2) Mapping Algorithm: map the scene depth to a predefined range on the display to avoid excessive perceived depth. A new method that dynamically adjusts the depth mapping from scene space to display space is presented in addition to an existing fixed depth mapping method. (3) Depth of Field Simulation: apply Depth of Field (DOF) blur effect to stereoscopic images. Only objects that are inside the DOF are viewed in full sharpness. Objects that are far away from the focus plane are blurred. We performed a human-based trial using the ITU-R BT.500-11 Recommendation to compare the depth quality of stereoscopic video sequences generated by the above-mentioned imaging methods. Our results indicate that viewers' practical 3D viewing volumes are different for individual stereoscopic displays and viewers can cope with much larger perceived depth range in viewing stereoscopic cinematography in comparison to static stereoscopic images. Our new dynamic depth mapping method does have an advantage over the fixed depth mapping method in controlling stereo depth perception. The DOF blur effect does not provide the expected improvement for perceived depth quality control in 3D cinematography

  2. A Voltage Mode Memristor Bridge Synaptic Circuit with Memristor Emulators

    Directory of Open Access Journals (Sweden)

    Leon Chua


    Full Text Available A memristor bridge neural circuit which is able to perform signed synaptic weighting was proposed in our previous study, where the synaptic operation was verified via software simulation of the mathematical model of the HP memristor. This study is an extension of the previous work advancing toward the circuit implementation where the architecture of the memristor bridge synapse is built with memristor emulator circuits. In addition, a simple neural network which performs both synaptic weighting and summation is built by combining memristor emulators-based synapses and differential amplifier circuits. The feasibility of the memristor bridge neural circuit is verified via SPICE simulations.

  3. Thermal energy storage apparatus, controllers and thermal energy storage control methods (United States)

    Hammerstrom, Donald J.


    Thermal energy storage apparatus, controllers and thermal energy storage control methods are described. According to one aspect, a thermal energy storage apparatus controller includes processing circuitry configured to access first information which is indicative of surpluses and deficiencies of electrical energy upon an electrical power system at a plurality of moments in time, access second information which is indicative of temperature of a thermal energy storage medium at a plurality of moments in time, and use the first and second information to control an amount of electrical energy which is utilized by a heating element to heat the thermal energy storage medium at a plurality of moments in time.

  4. Analytical Methods Used in the Quality Control of Honey. (United States)

    Pita-Calvo, Consuelo; Guerra-Rodríguez, María Esther; Vázquez, Manuel


    Honey is a natural sweet substance produced by bees (Apis mellifera). In this work, the main parameters used in routine quality control of honey and the most commonly used analytical methods for their determination are reviewed. Honey can be adulterated with cheaper sweeteners or, indirectly, by feeding the bees with sugars. Therefore, methods for detecting and quantifying adulteration are necessary. Chromatographic techniques are widely used in honey analysis. More recently, techniques such as Raman, near-infrared, mid-infrared, and nuclear magnetic resonance spectroscopy in combination with chemometric data processing have been proposed. However, spectroscopy does not allow the determination of enzyme activities, one criteria of great importance for the honey trade. Methylglyoxal is an interesting compound for its antibacterial properties. Methods for its determination are also reviewed.

  5. Method of laser beam coding for control systems (United States)

    Pałys, Tomasz; Arciuch, Artur; Walczak, Andrzej; Murawski, Krzysztof


    The article presents the method of encoding a laser beam for control systems. The experiments were performed using a red laser emitting source with a wavelength of λ = 650 nm and a power of P ≍ 3 mW. The aim of the study was to develop methods of modulation and demodulation of the laser beam. Results of research, in which we determined the effect of selected camera parameters, such as image resolution, number of frames per second on the result of demodulation of optical signal, is also shown in the paper. The experiments showed that the adopted coding method provides sufficient information encoded in a single laser beam (36 codes with the effectiveness of decoding at 99.9%).

  6. Highly efficient and controllable method to fabricate ultrafine metallic nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Hongbing; Zhang, Kun; Pan, Nan, E-mail:, E-mail:; Luo, Yi; Wang, Xiaoping, E-mail:, E-mail: [Hefei National Laboratory for Physical Sciences at the Microscale, University of Science & Technology of China, Hefei 230026 (China); Yu, Xinxin [Physics school, Anhui University, Hefei Anhui 230601 China (China); Tian, Yangchao [National Synchrotron Radiation Laboratory, University of Science & Technology of China, Hefei 230027 (China)


    We report a highly efficient, controllable and scalable method to fabricate various ultrafine metallic nanostructures in this paper. The method starts with the negative poly-methyl-methacrylate (PMMA) resist pattern with line-width superior to 20 nm, which is obtained from overexposing of the conventionally positive PMMA under a low energy electron beam. The pattern is further shrunk to sub-10 nm line-width through reactive ion etching. Using the patter as a mask, we can fabricate various ultrafine metallic nanostructures with the line-width even less than 10 nm. This ion tailored mask lithography (ITML) method enriches the top-down fabrication strategy and provides potential opportunity for studying quantum effects in a variety of materials.

  7. An Optimal Control Strategy for DC Bus Voltage Regulation in Photovoltaic System with Battery Energy Storage (United States)

    Daud, Muhamad Zalani; Mohamed, Azah; Hannan, M. A.


    This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV) system with battery energy storage (BES). The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC). For the grid side VSC (G-VSC), two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods. PMID:24883374

  8. An optimal control strategy for DC bus voltage regulation in photovoltaic system with battery energy storage. (United States)

    Daud, Muhamad Zalani; Mohamed, Azah; Hannan, M A


    This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV) system with battery energy storage (BES). The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC). For the grid side VSC (G-VSC), two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods.

  9. An Optimal Control Strategy for DC Bus Voltage Regulation in Photovoltaic System with Battery Energy Storage

    Directory of Open Access Journals (Sweden)

    Muhamad Zalani Daud


    Full Text Available This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV system with battery energy storage (BES. The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC. For the grid side VSC (G-VSC, two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods.

  10. Accelerometer method and apparatus for integral display and control functions (United States)

    Bozeman, Richard J., Jr. (Inventor)


    Vibration analysis has been used for years to provide a determination of the proper functioning of different types of machinery, including rotating machinery and rocket engines. A determination of a malfunction, if detected at a relatively early stage in its development, will allow changes in operating mode or a sequenced shutdown of the machinery prior to a total failure. Such preventative measures result in less extensive and/or less expensive repairs, and can also prevent a sometimes catastrophic failure of equipment. Standard vibration analyzers are generally rather complex, expensive, and of limited portability. They also usually result in displays and controls being located remotely from the machinery being monitored. Consequently, a need exists for improvements in accelerometer electronic display and control functions which are more suitable for operation directly on machines and which are not so expensive and complex. The invention includes methods and apparatus for detecting mechanical vibrations and outputting a signal in response thereto. The apparatus includes an accelerometer package having integral display and control functions. The accelerometer package is suitable for mounting upon the machinery to be monitored. Display circuitry provides signals to a bar graph display which may be used to monitor machine condition over a period of time. Control switches may be set which correspond to elements in the bar graph to provide an alert if vibration signals increase over the selected trip point. The circuitry is shock mounted within the accelerometer housing. The method provides for outputting a broadband analog accelerometer signal, integrating this signal to produce a velocity signal, integrating and calibrating the velocity signal before application to a display driver, and selecting a trip point at which a digitally compatible output signal is generated. The benefits of a vibration recording and monitoring system with controls and displays readily

  11. Digital reconstructed radiography quality control with software methods (United States)

    Denis, Eloise; Beaumont, Stephane; Guedon, JeanPierre


    Nowadays, most of treatments for external radiotherapy are prepared with Treatment Planning Systems (TPS) which uses a virtual patient generated by a set of transverse slices acquired with a CT scanner of the patient in treatment position 1 2 3. In the first step of virtual simulation, the TPS is used to define a ballistic allowing a good target covering and the lowest irradiation for normal tissues. This parameters optimisation of the treatment with the TPS is realised with particular graphic tools allowing to: ×Contour the target, ×Expand the limit of the target in order to take into account contouring uncertainties, patient set up errors, movements of the target during the treatment (internal movement of the target and external movement of the patient), and beam's penumbra, ×Determine beams orientation and define dimensions and forms of the beams, ×Visualize beams on the patient's skin and calculate some characteristic points which will be tattooed on the patient to assist the patient set up before treating, ×Calculate for each beam a Digital Reconstructed Radiography (DRR) consisting in projecting the 3D CT virtual patient and beam limits with a cone beam geometry onto a plane. These DRR allow one for insuring the patient positioning during the treatment, essentially bone structures alignment by comparison with real radiography realized with the treatment X-ray source in the same geometric conditions (portal imaging). Then DRR are preponderant to insure the geometric accuracy of the treatment. For this reason quality control of its computation is mandatory4 . Until now, this control is realised with real test objects including some special inclusions4 5 . This paper proposes to use some numerical test objects to control the quality DRR calculation in terms of computation time, beam angle, divergence and magnification precision, spatial and contrast resolutions. The main advantage of this proposed method is to avoid a real test object CT acquisition

  12. Urban drainage control applying rational method and geographic information technologies (United States)

    Aldalur, Beatriz; Campo, Alicia; Fernández, Sandra


    The objective of this study is to develop a method of controlling urban drainages in the town of Ingeniero White motivated by the problems arising as a result of floods, water logging and the combination of southeasterly and high tides. A Rational Method was applied to control urban watersheds and used tools of Geographic Information Technology (GIT). A Geographic Information System was developed on the basis of 28 panchromatic aerial photographs of 2005. They were georeferenced with control points measured with Global Positioning Systems (basin: 6 km2). Flow rates of basins and sub-basins were calculated and it was verified that the existing open channels have a low slope with the presence of permanent water and generate stagnation of water favored by the presence of trash. It is proposed for the output of storm drains, the use of an existing channel to evacuate the flow. The solution proposed in this work is complemented by the placement of three pumping stations: one on a channel to drain rain water which will allow the drain of the excess water from the lower area where is located the Ingeniero White city and the two others that will drain the excess liquid from the port area.

  13. Improved methods for the mathematically controlled comparison of biochemical systems

    Directory of Open Access Journals (Sweden)

    Schwacke John H


    Full Text Available Abstract The method of mathematically controlled comparison provides a structured approach for the comparison of alternative biochemical pathways with respect to selected functional effectiveness measures. Under this approach, alternative implementations of a biochemical pathway are modeled mathematically, forced to be equivalent through the application of selected constraints, and compared with respect to selected functional effectiveness measures. While the method has been applied successfully in a variety of studies, we offer recommendations for improvements to the method that (1 relax requirements for definition of constraints sufficient to remove all degrees of freedom in forming the equivalent alternative, (2 facilitate generalization of the results thus avoiding the need to condition those findings on the selected constraints, and (3 provide additional insights into the effect of selected constraints on the functional effectiveness measures. We present improvements to the method and related statistical models, apply the method to a previously conducted comparison of network regulation in the immune system, and compare our results to those previously reported.

  14. Radiation heat transfer calculations using a control-angle, control-volume-based discrete ordinates method

    Energy Technology Data Exchange (ETDEWEB)

    Chai, J.C.; Lee, H.S.; Patankar, S.V. (Minnesota Univ., Minneapolis (United States) NASA, Lewis Research Center, Cleveland, OH (United States))


    A control-angle, control-volume-based discrete ordinates method (CA - CV DOM) is presented in this paper. A detailed formulation of the discretization equation is presented in two-dimensional Cartesian coordinate system. The procedure can be extended to curvilinear coordinate system with minor modifications. The step and modified-exponential schemes are used in this study. Present results converged to the grid independent solutions quickly and compared favorably against other published results for six test problems. 27 refs.

  15. Control system and method for a universal power conditioning system (United States)

    Lai, Jih-Sheng; Park, Sung Yeul; Chen, Chien-Liang


    A new current loop control system method is proposed for a single-phase grid-tie power conditioning system that can be used under a standalone or a grid-tie mode. This type of inverter utilizes an inductor-capacitor-inductor (LCL) filter as the interface in between inverter and the utility grid. The first set of inductor-capacitor (LC) can be used in the standalone mode, and the complete LCL can be used for the grid-tie mode. A new admittance compensation technique is proposed for the controller design to avoid low stability margin while maintaining sufficient gain at the fundamental frequency. The proposed current loop controller system and admittance compensation technique have been simulated and tested. Simulation results indicate that without the admittance path compensation, the current loop controller output duty cycle is largely offset by an undesired admittance path. At the initial simulation cycle, the power flow may be erratically fed back to the inverter causing catastrophic failure. With admittance path compensation, the output power shows a steady-state offset that matches the design value. Experimental results show that the inverter is capable of both a standalone and a grid-tie connection mode using the LCL filter configuration.

  16. Method of Computer-aided Instruction in Situation Control Systems

    Directory of Open Access Journals (Sweden)

    Anatoliy O. Kargin


    Full Text Available The article considers the problem of computer-aided instruction in context-chain motivated situation control system of the complex technical system behavior. The conceptual and formal models of situation control with practical instruction are considered. Acquisition of new behavior knowledge is presented as structural changes in system memory in the form of situational agent set. Model and method of computer-aided instruction represent formalization, based on the nondistinct theories by physiologists and cognitive psychologists.The formal instruction model describes situation and reaction formation and dependence on different parameters, effecting education, such as the reinforcement value, time between the stimulus, action and the reinforcement. The change of the contextual link between situational elements when using is formalized.The examples and results of computer instruction experiments of the robot device “LEGO MINDSTORMS NXT”, equipped with ultrasonic distance, touch, light sensors.

  17. Improved methods in neural network-based adaptive output feedback control, with applications to flight control (United States)

    Kim, Nakwan

    Utilizing the universal approximation property of neural networks, we develop several novel approaches to neural network-based adaptive output feedback control of nonlinear systems, and illustrate these approaches for several flight control applications. In particular, we address the problem of non-affine systems and eliminate the fixed point assumption present in earlier work. All of the stability proofs are carried out in a form that eliminates an algebraic loop in the neural network implementation. An approximate input/output feedback linearizing controller is augmented with a neural network using input/output sequences of the uncertain system. These approaches permit adaptation to both parametric uncertainty and unmodeled dynamics. All physical systems also have control position and rate limits, which may either deteriorate performance or cause instability for a sufficiently high control bandwidth. Here we apply a method for protecting an adaptive process from the effects of input saturation and time delays, known as "pseudo control hedging". This method was originally developed for the state feedback case, and we provide a stability analysis that extends its domain of applicability to the case of output feedback. The approach is illustrated by the design of a pitch-attitude flight control system for a linearized model of an R-50 experimental helicopter, and by the design of a pitch-rate control system for a 58-state model of a flexible aircraft consisting of rigid body dynamics coupled with actuator and flexible modes. A new approach to augmentation of an existing linear controller is introduced. It is especially useful when there is limited information concerning the plant model, and the existing controller. The approach is applied to the design of an adaptive autopilot for a guided munition. Design of a neural network adaptive control that ensures asymptotically stable tracking performance is also addressed.

  18. Improved statistical method for temperature and salinity quality control (United States)

    Gourrion, Jérôme; Szekely, Tanguy


    Climate research and Ocean monitoring benefit from the continuous development of global in-situ hydrographic networks in the last decades. Apart from the increasing volume of observations available on a large range of temporal and spatial scales, a critical aspect concerns the ability to constantly improve the quality of the datasets. In the context of the Coriolis Dataset for ReAnalysis (CORA) version 4.2, a new quality control method based on a local comparison to historical extreme values ever observed is developed, implemented and validated. Temperature, salinity and potential density validity intervals are directly estimated from minimum and maximum values from an historical reference dataset, rather than from traditional mean and standard deviation estimates. Such an approach avoids strong statistical assumptions on the data distributions such as unimodality, absence of skewness and spatially homogeneous kurtosis. As a new feature, it also allows addressing simultaneously the two main objectives of an automatic quality control strategy, i.e. maximizing the number of good detections while minimizing the number of false alarms. The reference dataset is presently built from the fusion of 1) all ARGO profiles up to late 2015, 2) 3 historical CTD datasets and 3) the Sea Mammals CTD profiles from the MEOP database. All datasets are extensively and manually quality controlled. In this communication, the latest method validation results are also presented. The method has already been implemented in the latest version of the delayed-time CMEMS in-situ dataset and will be deployed soon in the equivalent near-real time products.

  19. Methods of measurement for semiconductor materials, process control, and devices (United States)

    Bullis, W. M. (Editor)


    Activities directed toward the development of methods of measurement for semiconductor materials, process control, and devices are described. Topics investigated include: measurements of transistor delay time; application of the infrared response technique to the study of radiation-damaged, lithium-drifted silicon detectors; and identification of a condition that minimizes wire flexure and reduces the failure rate of wire bonds in transistors and integrated circuits under slow thermal cycling conditions. Supplementary data concerning staff, standards committee activities, technical services, and publications are included as appendixes.

  20. Enhanced Temperature Control Method Using ANFIS with FPGA

    Directory of Open Access Journals (Sweden)

    Chiung-Wei Huang


    Full Text Available Temperature control in etching process is important for semiconductor manufacturing technology. However, pressure variations in vacuum chamber results in a change in temperature, worsening the accuracy of the temperature of the wafer and the speed and quality of the etching process. This work develops an adaptive network-based fuzzy inference system (ANFIS using a field-programmable gate array (FPGA to improve the effectiveness. The proposed method adjusts every membership function to keep the temperature in the chamber stable. The improvement of the proposed algorithm is confirmed using a medium vacuum (MV inductively-coupled plasma- (ICP- type etcher.

  1. System and method for controlling a combustor assembly (United States)

    York, William David; Ziminsky, Willy Steve; Johnson, Thomas Edward; Stevenson, Christian Xavier


    A system and method for controlling a combustor assembly are disclosed. The system includes a combustor assembly. The combustor assembly includes a combustor and a fuel nozzle assembly. The combustor includes a casing. The fuel nozzle assembly is positioned at least partially within the casing and includes a fuel nozzle. The fuel nozzle assembly further defines a head end. The system further includes a viewing device configured for capturing an image of at least a portion of the head end, and a processor communicatively coupled to the viewing device, the processor configured to compare the image to a standard image for the head end.


    Directory of Open Access Journals (Sweden)

    C. Cantoni


    Full Text Available This study is aimed at the development of a method for integrated mite control in the industrial production of speck. The investigation were carried out on the premises of five factories in the north-east of Italy. Tyrophagus putrescentiae and T. longior were predominant. The gaseous ozone treatment at low level (0.4 ppm was able to kill mites in a period within 15 days and 1 month. The characteristic layer of mould on the product surface reappears within 1 month from the end of treatment with ozone.

  3. GPON system with user controlled port-ID assignment method (United States)

    Zhang, Na; Yoshiuchi, Hideya


    Passive Optical Network (PON) system with characters of low-cost and high-efficiency has become a promising solution for access network in relieving the bandwidth bottleneck problem. PON system can provide high-speed optical subscriber networks with broad bandwidth and long distance transmission. In current telecommunication carriers' PON system, different service has its given priority which is configured by carriers based on common requirements. However, different users have their own requirement and inflexibility of the given default service priority causes users' inconvenience and frustration. In this paper, we propose a novel method of user controlled Port-IDentifier (Port-ID) assignment in a Gigabit-capable PON (GPON) system. This method provides users a more individualized priority determination mechanism for end users through assigning a multi-level Port-ID to different service. Then users can manage their own bandwidth based on their requirements for different service and carriers can provide a flexible service management mechanism.

  4. Time-dependent optimal heater control using finite difference method

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhen Zhe; Heo, Kwang Su; Choi, Jun Hoo; Seol, Seoung Yun [Chonnam National Univ., Gwangju (Korea, Republic of)


    Thermoforming is one of the most versatile and economical process to produce polymer products. The drawback of thermoforming is difficult to control thickness of final products. Temperature distribution affects the thickness distribution of final products, but temperature difference between surface and center of sheet is difficult to decrease because of low thermal conductivity of ABS material. In order to decrease temperature difference between surface and center, heating profile must be expressed as exponential function form. In this study, Finite Difference Method was used to find out the coefficients of optimal heating profiles. Through investigation, the optimal results using Finite Difference Method show that temperature difference between surface and center of sheet can be remarkably minimized with satisfying temperature of forming window.

  5. Efficient model learning methods for actor-critic control. (United States)

    Grondman, Ivo; Vaandrager, Maarten; Buşoniu, Lucian; Babuska, Robert; Schuitema, Erik


    We propose two new actor-critic algorithms for reinforcement learning. Both algorithms use local linear regression (LLR) to learn approximations of the functions involved. A crucial feature of the algorithms is that they also learn a process model, and this, in combination with LLR, provides an efficient policy update for faster learning. The first algorithm uses a novel model-based update rule for the actor parameters. The second algorithm does not use an explicit actor but learns a reference model which represents a desired behavior, from which desired control actions can be calculated using the inverse of the learned process model. The two novel methods and a standard actor-critic algorithm are applied to the pendulum swing-up problem, in which the novel methods achieve faster learning than the standard algorithm.

  6. Bi-level Control and Chopper Control Methods for Improving the Dynamic Performance of Stepper Motor


    Dr. Walid Emar, Eng. Ziad Sobih, Dr. Musbah Aqel & Dr. Mahmoud Awad


    This paper compares between chopper control method and bi-level controlmethod. Both methods are used for improving the dynamic performance ofvariable reluctance stepper motor (VRSM) by modifying its time constant andthus, increasing its stepping rate. Therefore, the initial torque developed by themotor is high; the switching from one coil to the next is faster than normal andconsequently, the rotor moves as quickly as it should be. The circuitry discussedin this paper is connected directly to...

  7. Battery Equalization Control Based on the Shunt Transistor Method

    Directory of Open Access Journals (Sweden)

    Gallardo-Lozano Javier


    Full Text Available Electric Vehicle (EV researches are currently becoming of special importance and the EV battery system is particularly relevant in the EV design. In these applications, series connected batteries are necessary since a single battery cannot achieve the voltage requirements. Internal and external sources lead the batteries string to become unbalanced, which is an important factor to be taken into account, as premature cells degradation, safety hazards, and reduced capacity will occur for unbalanced systems. The different balancing methods are presented and compared in this paper, and finally the switch capacitor and the double-tiered switching capacitor are considered the best option. However, their speed depends on the voltage difference between the batteries in the string, and when their voltage difference is low, the equalization speed decreases significantly, leading the battery pack to be unbalanced for longer. A novel equalization method is presented, that improves the aforementioned methods performance by applying a new control to a shunt transistor method. Low cost, size, and complexity, together with higher speed and efficiency are obtained. A prototype has been built, and experimental results are presented.

  8. A control system for and a method of controlling a superconductive rotating electrical machine

    DEFF Research Database (Denmark)


    This invention relates to a method of controlling and a control system (100) for a superconductive rotating electric machine (200) comprising at least one superconductive winding (102; 103), where the control system (100) is adapted to control a power unit (101) supplying during use the at least...... or more actual values (110, 111)of one or more parameters for a given superconductive winding (102; 103), each parameter representing a physical condition of the given superconductive winding (102; 103), and to dynamically derive one or more electrical current values to be maintained in the given...... superconductive winding (102; 103) by the power unit (101) where the one or more electrical current values is/are derived taking into account the received one or more actual values (110, 111). In this way,greater flexibility and more precise control of the performance of the superconducting rotating electrical...

  9. An Improved Method to Control the Critical Parameters of a Multivariable Control System (United States)

    Subha Hency Jims, P.; Dharmalingam, S.; Wessley, G. Jims John


    The role of control systems is to cope with the process deficiencies and the undesirable effect of the external disturbances. Most of the multivariable processes are highly iterative and complex in nature. Aircraft systems, Modern Power Plants, Refineries, Robotic systems are few such complex systems that involve numerous critical parameters that need to be monitored and controlled. Control of these important parameters is not only tedious and cumbersome but also is crucial from environmental, safety and quality perspective. In this paper, one such multivariable system, namely, a utility boiler has been considered. A modern power plant is a complex arrangement of pipework and machineries with numerous interacting control loops and support systems. In this paper, the calculation of controller parameters based on classical tuning concepts has been presented. The controller parameters thus obtained and employed has controlled the critical parameters of a boiler during fuel switching disturbances. The proposed method can be applied to control the critical parameters like elevator, aileron, rudder, elevator trim rudder and aileron trim, flap control systems of aircraft systems.

  10. The effectivity of toothpick tooth brushing method on plaque control

    Directory of Open Access Journals (Sweden)

    Chiquita Prahasanti


    Full Text Available Background: Periodontal diseases are associated with bacteria species which present in biofilms that colonize on dental surfaces. Several tooth brushing methods had been known and proved to be effective in maintaining oral hygiene. Among them, tooth pick technique was a relatively new method and its superiority in removing interproximal plaque was better than other methods. Purpose: The purpose of this study was to examine the effectivity of toothpick tooth brushing method to conventional method on periodontal health. Methods: This research was designed as an analytical observational study. Thirty samples selected from five hundred and twelve males Indonesian Air-force members in Malang, aged 18–40 yrs, with periodontal pockets (≤ 5 mm in upper or lower teeth, without crowding, gingival index minimal > 1 (moderate gingivitis, OHI-S score minimal ≥ 1.3 (moderate, without systemic diseases, do not undergone medical therapy/drug prescriptions, without using mouth rinse during study, and without prosthesis. There were thirty samples in this research and devided to two groups, fifteen samples easch. The groups were toothpick tooth brusing method and conventional method (control group. In this study oral hygiene index simplified (OHI-S, gingival index (GI, bleeding on probing (BOP and pocket depth were examined. Results: There were significant differences (p = .001 in OHI-S, GI, BOP, and PD before and after conducting each toothbrushing method, as well as differences between means (quarrel means, that were p = .003; p = .001; p = .001 and p = .001 consecutively. Conclusion: Toothpick brushing method was more effective in plaque control compared to conventional method.Latar belakang: Penyakit periodontal berhubungan dengan bakteri yang berkoloni dalam biofilm yang terdapat di permukaan gigi. Saat ini telah dikenal berbagai macam metode menyikat gigi tetapi masih belum ada penelitian tentang efek metode tersebut terhadap OHI-S. Penelitian in ingin

  11. Pipeline heating method based on optimal control and state estimation

    Energy Technology Data Exchange (ETDEWEB)

    Vianna, F.L.V. [Dept. of Subsea Technology. Petrobras Research and Development Center - CENPES, Rio de Janeiro, RJ (Brazil)], e-mail:; Orlande, H.R.B. [Dept. of Mechanical Engineering. POLI/COPPE, Federal University of Rio de Janeiro - UFRJ, Rio de Janeiro, RJ (Brazil)], e-mail:; Dulikravich, G.S. [Dept. of Mechanical and Materials Engineering. Florida International University - FIU, Miami, FL (United States)], e-mail:


    In production of oil and gas wells in deep waters the flowing of hydrocarbon through pipeline is a challenging problem. This environment presents high hydrostatic pressures and low sea bed temperatures, which can favor the formation of solid deposits that in critical operating conditions, as unplanned shutdown conditions, may result in a pipeline blockage and consequently incur in large financial losses. There are different methods to protect the system, but nowadays thermal insulation and chemical injection are the standard solutions normally used. An alternative method of flow assurance is to heat the pipeline. This concept, which is known as active heating system, aims at heating the produced fluid temperature above a safe reference level in order to avoid the formation of solid deposits. The objective of this paper is to introduce a Bayesian statistical approach for the state estimation problem, in which the state variables are considered as the transient temperatures within a pipeline cross-section, and to use the optimal control theory as a design tool for a typical heating system during a simulated shutdown condition. An application example is presented to illustrate how Bayesian filters can be used to reconstruct the temperature field from temperature measurements supposedly available on the external surface of the pipeline. The temperatures predicted with the Bayesian filter are then utilized in a control approach for a heating system used to maintain the temperature within the pipeline above the critical temperature of formation of solid deposits. The physical problem consists of a pipeline cross section represented by a circular domain with four points over the pipe wall representing heating cables. The fluid is considered stagnant, homogeneous, isotropic and with constant thermo-physical properties. The mathematical formulation governing the direct problem was solved with the finite volume method and for the solution of the state estimation problem

  12. Adaptive model-based control systems and methods for controlling a gas turbine (United States)

    Brunell, Brent Jerome (Inventor); Mathews, Jr., Harry Kirk (Inventor); Kumar, Aditya (Inventor)


    Adaptive model-based control systems and methods are described so that performance and/or operability of a gas turbine in an aircraft engine, power plant, marine propulsion, or industrial application can be optimized under normal, deteriorated, faulted, failed and/or damaged operation. First, a model of each relevant system or component is created, and the model is adapted to the engine. Then, if/when deterioration, a fault, a failure or some kind of damage to an engine component or system is detected, that information is input to the model-based control as changes to the model, constraints, objective function, or other control parameters. With all the information about the engine condition, and state and directives on the control goals in terms of an objective function and constraints, the control then solves an optimization so the optimal control action can be determined and taken. This model and control may be updated in real-time to account for engine-to-engine variation, deterioration, damage, faults and/or failures using optimal corrective control action command(s).

  13. Watershed safety and quality control by safety threshold method (United States)

    Da-Wei Tsai, David; Mengjung Chou, Caroline; Ramaraj, Rameshprabu; Liu, Wen-Cheng; Honglay Chen, Paris


    Taiwan was warned as one of the most dangerous countries by IPCC and the World Bank. In such an exceptional and perilous island, we would like to launch the strategic research of land-use management on the catastrophe prevention and environmental protection. This study used the watershed management by "Safety Threshold Method" to restore and to prevent the disasters and pollution on island. For the deluge prevention, this study applied the restoration strategy to reduce total runoff which was equilibrium to 59.4% of the infiltration each year. For the sediment management, safety threshold management could reduce the sediment below the equilibrium of the natural sediment cycle. In the water quality issues, the best strategies exhibited the significant total load reductions of 10% in carbon (BOD5), 15% in nitrogen (nitrate) and 9% in phosphorus (TP). We found out the water quality could meet the BOD target by the 50% peak reduction with management. All the simulations demonstrated the safety threshold method was helpful to control the loadings within the safe range of disasters and environmental quality. Moreover, from the historical data of whole island, the past deforestation policy and the mistake economic projects were the prime culprits. Consequently, this study showed a practical method to manage both the disasters and pollution in a watershed scale by the land-use management.

  14. Method and apparatus for recirculation with control of synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Douglas, David R.; Tennant, Christopher


    A method for controlling beam quality degradation from ISR and CSR and stabilizing the microbunching instability (.mu.BI) in a high brightness electron beam. The method includes providing a super-periodic second order achromat line with each super period being individually linearly achromatic and isochronous, setting individual superperiod tunes to rational fractions of an integer (such as or integers), setting individual bend angles to be as small as practical to reduce driving terms due to dispersion and dispersive angle, and setting bend radii as large enough to suppress ISR but not negatively affect the radial dependence of CSR. The method includes setting the structure of the individual superperiods to minimize bend plane beam envelope values in the dipoles to reduce betatron response to a CSR event at a dispersed location, increasing beam angular divergence, and creating dispersion nodes in the dipoles to similarly reduce response to CSR events, and limit R.sub.56 modulation in order to mitigate .mu.BI.

  15. Modeling and simulation of aeroservoelastic control with multiple control surfaces using mu-method (United States)

    Teng, Ying

    A modeling and simulation approach to predicting the robust stability of a nonlinear aeroservoelastic system via the mu-method is presented. Mathematical models and implementation issues for the multi-input/multi-output (MIMO) aeroservoelastic system simulation developed for a flexible prototypical wing with leading and trailing edge control surfaces are described. The improvements in the aeroservoelastic analysis and the active flutter suppression (AFS) of a flexible wing structure with multiple control surfaces is accomplished using the mu-method with the uncertainty parameters/perturbations associated with unsteady dynamic pressure, variable structural damping and nonlinear structural stiffness. The motivation of this research is to develop an effective and more accurate methodology in aeroservoelastic analysis by improving the current analysis methods so that it can be readily applied to an aeroservoelastic system design with the validation of test data, and to determine the dynamic performance of an aeroservoelastic system which includes time and frequency responses, system modal properties, critical flutter airspeeds and stability margins. The mu-control law and algorithms for an aeroservoelastic system with leading and trailing edge control surfaces are developed by combining the MIMO analytical aeroservoelastic model with test data by means of the linear fractional transformation (LFT) and a set of norm-bounded operators (perturbations) Delta that describe modeling errors and uncertainties in the mu-framework. The relevant theories of structural dynamics, aerodynamics, and modern feedback control, as well as flutter, frequency response, poles and stability, aeroservoelasticity/structural-coupling, and mu-based analysis applied to derive the mu-control law for the aeroservoelastic control system are examined. Simulation results are presented for comparisons of the following: (a) the uncontrolled flexible wing, (b) the active flexible wing with a single

  16. Electrical energy consumption control apparatuses and electrical energy consumption control methods (United States)

    Hammerstrom, Donald J.


    Electrical energy consumption control apparatuses and electrical energy consumption control methods are described. According to one aspect, an electrical energy consumption control apparatus includes processing circuitry configured to receive a signal which is indicative of current of electrical energy which is consumed by a plurality of loads at a site, to compare the signal which is indicative of current of electrical energy which is consumed by the plurality of loads at the site with a desired substantially sinusoidal waveform of current of electrical energy which is received at the site from an electrical power system, and to use the comparison to control an amount of the electrical energy which is consumed by at least one of the loads of the site.

  17. Variable Camber Continuous Aerodynamic Control Surfaces and Methods for Active Wing Shaping Control (United States)

    Nguyen, Nhan T. (Inventor)


    An aerodynamic control apparatus for an air vehicle improves various aerodynamic performance metrics by employing multiple spanwise flap segments that jointly form a continuous or a piecewise continuous trailing edge to minimize drag induced by lift or vortices. At least one of the multiple spanwise flap segments includes a variable camber flap subsystem having multiple chordwise flap segments that may be independently actuated. Some embodiments also employ a continuous leading edge slat system that includes multiple spanwise slat segments, each of which has one or more chordwise slat segment. A method and an apparatus for implementing active control of a wing shape are also described and include the determination of desired lift distribution to determine the improved aerodynamic deflection of the wings. Flap deflections are determined and control signals are generated to actively control the wing shape to approximate the desired deflection.

  18. Effectiveness of quality control methods for glomerular filtration rate calculation. (United States)

    McMeekin, Helena; Wickham, Fred; Barnfield, Mark; Burniston, Maria


    In this work, we aimed to identify the types of errors encountered in glomerular filtration rate (GFR) measurement and test the effectiveness of all published quality control (QC) methods for detection of clinically significant errors. A total of 412 GFR tests were carried out on adults and children. The three-point slope-intercept glomerular filtration rate (SI-GFR) was compared with the nine-point 'area under curve' calculation as a gold standard to determine the error in SI-GFR. The Durbin-Watson test was used to characterize the nature of the errors. The sensitivity, specificity and positive predictive value (PPV) of QC methods for detecting clinically significant errors were calculated and receiver operating characteristic curves were constructed. The QC methods were also applied to a dataset of 100 four-point GFR tests from different institutions. Model failure is the dominant cause of clinically significant error in this dataset, with individual point measurement errors only giving rise to clinically significant errors in a small number of cases. No QC test had an acceptable combination of sensitivity, PPV and specificity. The correlation coefficient QC test had the largest area under the receiver operating characteristic curve (0.73). No other QC test had an area greater than 0.57. All the QC methods have poor sensitivity and PPV for detecting clinically significant errors and so cannot be relied on to ensure a robust measurement of GFR, underlining the need for careful working practices and a thorough system of measurement checks. We found no evidence for the value of multiple sampling with respect to QC; until such evidence is published, their clinical utility is unproven.

  19. Interpolation functions in control volume finite element method (United States)

    Abbassi, H.; Turki, S.; Nasrallah, S. Ben

    The main contribution of this paper is the study of interpolation functions in control volume finite element method used in equal order and applied to an incompressible two-dimensional fluid flow. Especially, the exponential interpolation function expressed in the elemental local coordinate system is compared to the classic linear interpolation function expressed in the global coordinate system. A quantitative comparison is achieved by the application of these two schemes to four flows that we know the analytical solutions. These flows are classified in two groups: flows with privileged direction and flows without. The two interpolation functions are applied to a triangular element of the domain then; a direct comparison of the results given by each interpolation function to the exact value is easily realized. The two functions are also compared when used to solve the discretized equations over the entire domain. Stability of the numerical process and accuracy of solutions are compared.

  20. Apparatus and methods for controlling electron microscope stages (United States)

    Duden, Thomas


    Methods and apparatus for generating an image of a specimen with a microscope (e.g., TEM) are disclosed. In one aspect, the microscope may generally include a beam generator, a stage, a detector, and an image generator. A plurality of crystal parameters, which describe a plurality of properties of a crystal sample, are received. In a display associated with the microscope, an interactive control sphere based at least in part on the received crystal parameters and that is rotatable by a user to different sphere orientations is presented. The sphere includes a plurality of stage coordinates that correspond to a plurality of positions of the stage and a plurality of crystallographic pole coordinates that correspond to a plurality of polar orientations of the crystal sample. Movement of the sphere causes movement of the stage, wherein the stage coordinates move in conjunction with the crystallographic coordinates represented by pole positions so as to show a relationship between stage positions and the pole positions.

  1. The meat product quality control by a polarimetric method (United States)

    Blokhina, Anastasia A.; Ryzhova, Victoria A.; Korotaev, Valery V.; Kleshchenok, Maksim A.


    Analysis of the polarization characteristics of the scattered radiation of biological tissues in some cases provides a qualitatively new results in the study of biological samples. These results can be used in medicine and food industry. As a result of the work, it was determined that the high concentration of scattering particles, the nonuniformity of their dimensions, forms make the task of creating an adequate optical model of a biotissue quite difficult, though many interesting tissue properties can be potentially studied by means of polarized light. In this case, the method for control the freshness of meat samples is considered for by obtaining the Stokes parameters of the polarized radiation scattered forward by the meat product.

  2. An evaluation of the osmotic method of controlling suction

    CERN Document Server

    Delage, Pierre


    Experimental techniques of testing the mechanical properties of unsaturated soils are complex and difficult to conduct. As a consequence, complete sets of parameters that characterise the behaviour of unsaturated soils remain scarce and necessary. In this context, it has been found useful to gather the information obtained after some years of practice of the osmotic technique of controlling suction. As compared to the more documented axis-translation technique, the osmotic technique has its own advantages and drawbacks that are discussed in this paper, together with some potential future developments. The osmotic method has been developed by soil scientists in the 1960s and adapted to geotechnical testing in the early 1970s. This paper presents the osmotic technique and comments on its advantages (including suction condition close to reality and higher suctions easily attained) and drawbacks (including some concern with the membrane resistance and some membrane effects in the suction/concentration calibration...


    Directory of Open Access Journals (Sweden)

    Khokhlova KO


    Full Text Available Introduction. Hawthorn tincture is one of the most used herbal drugs at the domestic pharmaceutical market. According to the State register of drugs at the pharmaceutical market of Ukraine, there are 13 commercial offers of Hawthorn tincture from home-produced manufactures. The initial herbal raw materials for Hawthorn tincture are Hawthorn fruits, which are widespread at the territory of Ukraine. These are pharmacopoeial herbal raw material. Thus, 12 different species of Hawthorn fruits are included into monograph of Ukrainian State Pharmacopoeia (SPhU and State Pharmacopoeia of USSR XI ed. On the territory of Ukraine there are near 30 different species of Hawthorn, and the quantity of species is much arises due to its forms and hybrids. The ‘natural variability’ of bioactive substances of Hawthorn fruits of the same species and possibility of usage of many different species during manufacturing process of herbal drugs lead to the pitfalls in standardization of herbal drugs in general, and Hawthorn tincture particularly, and should be taken in mind while development of its quality control methods. For development of specific and reproducible identification method, it is necessary to ensure the number of parameters: usage of method and equipment that give reproducible results; big selections of different samples; rigorously observation of method’s procedure of implementation. The modern, automated HPTLC method of analysis was chosen for identification purpose. If standardize procedure and suitable equipment are used, the reproducible results of the method have to be obtained. The aim of this paper was development of HPTLC method for identification of Hawthorn tincture, which could be appropriated for stability study and establishment of its expire date. Materials and Methods. In research 13 samples of Hawthorn tinctures from 8 manufactures from Ukraine and Russia were analyzed. These samples were manufactured in 2010, 2014, 2015 years. The

  4. Phase change thermal control materials, method and apparatus (United States)

    Buckley, Theresa M. (Inventor)


    An apparatus and method for metabolic cooling and insulation of a user in a cold environment. In its preferred embodiment the apparatus is a highly flexible composite material having a flexible matrix containing a phase change thermal storage material. The apparatus can be made to heat or cool the body or to act as a thermal buffer to protect the wearer from changing environmental conditions. The apparatus may also include an external thermal insulation layer and/or an internal thermal control layer to regulate the rate of heat exchange between the composite and the skin of the wearer. Other embodiments of the apparatus also provide 1) a path for evaporation or direct absorption of perspiration from the skin of the wearer for improved comfort and thermal control, 2) heat conductive pathways within the material for thermal equalization, 3) surface treatments for improved absorption or rejection of heat by the material, and 4) means for quickly regenerating the thermal storage capacity for reuse of the material. Applications of the composite materials are also described which take advantage of the composite's thermal characteristics. The examples described include a diver's wet suit, ski boot liners, thermal socks, gloves and a face mask for cold weather activities, and a metabolic heating or cooling blanket useful for treating hypothermia or fever patients in a medical setting and therapeutic heating or cooling orthopedic joint supports.

  5. Controlling Smart Green House Using Fuzzy Logic Method

    Directory of Open Access Journals (Sweden)

    Rafiuddin Syam


    Full Text Available To increase agricultural output it is needed a system that can help the environmental conditions for optimum plant growth. Smart greenhouse allows for plants to grow optimally, because the temperature and humidity can be controlled so that no drastic changes. It is necessary for optimal smart greenhouse needed a system to manipulate the environment in accordance with the needs of the plant. In this case the setting temperature and humidity in the greenhouse according to the needs of the plant. So using an automated system for keeping such environmental condition is important. In this study, the authors use fuzzy logic to make the duration of watering the plants more dynamic in accordance with the input temperature and humidity so that the temperature and humidity in the green house plants maintained in accordance to the reference condition. Based on the experimental results using fuzzy logic method is effective to control the duration of watering and to maintain the optimum temperature and humidity inside the greenhouse

  6. Method for controlling a laser additive process using intrinsic illumination (United States)

    Tait, Robert; Cai, Guoshuang; Azer, Magdi; Chen, Xiaobin; Liu, Yong; Harding, Kevin


    One form of additive manufacturing is to use a laser to generate a melt pool from powdered metal that is sprayed from a nozzle. The laser net-shape machining system builds the part a layer at a time by following a predetermined path. However, because the path may need to take many turns, maintaining a constant melt pool may not be easy. A straight section may require one speed and power while a sharp bend would over melt the metal at the same settings. This paper describes a process monitoring method that uses the intrinsic IR radiation from the melt pool along with a process model configured to establish target values for the parameters associated with the manufacture or repair. This model is based upon known properties of the metal being used as well as the properties of the laser beam. An adaptive control technique is then employed to control process parameters of the machining system based upon the real-time weld pool measurement. Since the system uses the heat radiant from the melt pool, other previously deposited metal does not confuse the system as only the melted material is seen by the camera.

  7. Integrated Parasite Management for Livestock - Alternative control methods

    Directory of Open Access Journals (Sweden)

    Souvik Paul1

    Full Text Available Internal parasites are considered by some to be one of the most economically important constraints in raising livestock. The growing concern about the resistance of internal parasites to all classes of dewormers has caused people to look for alternatives. As dewormers lose their effectiveness, the livestock community fears increasing economic losses from worms. There is no one thing that can be given or done to replace chemical dewormers. It will take a combination of extremely good management techniques and possibly some alternative therapies. It is not wise to think that one can just stop deworming animals with chemical dewormers. It is something one will need to change gradually, observing and testing animals and soil, in order to monitor the progress. Alternative parasite control is an area that is receiving a lot of interest and attention. Programs and research will continue in the pursuit of parasite control, using alternative and more management-intensive methods. [Veterinary World 2010; 3(9.000: 431-435

  8. Passive control of thermoacoustic oscillations with adjoint methods (United States)

    Aguilar, Jose; Juniper, Matthew


    Strict pollutant regulations are driving gas turbine manufacturers to develop devices that operate under lean premixed conditions, which produce less NOx but encourage thermoacoustic oscillations. These are a form of unstable combustion that arise due to the coupling between the acoustic field and the fluctuating heat release in a combustion chamber. In such devices, in which safety is paramount, thermoacoustic oscillations must be eliminated passively, rather than through feedback control. The ideal way to eliminate thermoacoustic oscillations is by subtly changing the shape of the device. To achieve this, one must calculate the sensitivity of each unstable thermoacoustic mode to every geometric parameter. This is prohibitively expensive with standard methods, but is relatively cheap with adjoint methods. In this study we first present low-order network models as a tool to model and study the thermoacoustic behaviour of combustion chambers. Then we compute the continuous adjoint equations and the sensitivities to relevant parameters. With this, we run an optimization routine that modifies the parameters in order to stabilize all the resonant modes of a laboratory combustor rig.

  9. Review on methods of golden mussel control in pires

    Directory of Open Access Journals (Sweden)

    Edemir Luiz Kowalski


    Full Text Available At the beginning of the 90’s, they were detected in Rio da Prata in Argentina the first samples of the exotic specie named limnoperna fortunei, from Asia, maybe introduced through ballast water of ships came from Asia. In Brazil the first samples were detected in Lagoa dos Patos in Rio Grande do Sul in the 90’s, possibly by the same reason. A second axis was verified in Campo Grande in Mato Grosso do Sul derived probably from Argentina because of the navigation through the Paraguay river going down to Lagoa de Itaipú causing its contamination. The invader specie has the capacity of fouling pipings where the contaminated water circulates, causing considerable financial damage to the infected industries. In Brazil the indrustries located in Rio Grande do Sul as well as hydroelectric plants as Itaipu, they manage these problems stopping the equipments for their maintenance and cleaning more times than the habitual. The United States of America and Canada already have the same kind of problem with the similar specie found here in Brazil. The target of this work is to introduce a review about the main methods to control the golden mussel mollusk without using any kind of chemical products, based on The USA and Canada’s experiences, where there are similar problems but with the specie zebra mussel. Key-words: Non Chemicals Methods, Golden Mussel, Zebra Mussel

  10. From the new Austrian tunneling method to the geoengineering condition evaluation and dynamic controlling method

    Directory of Open Access Journals (Sweden)

    Yanjun Shang


    Full Text Available The new Austrian tunneling method (NATM is widely applied in design and construction of underground engineering projects. When the type and distribution of unfavorable geological bodies (UGBs associated with their influences on geoengineering are complicated or unfortunately are overlooked, we should pay more attentions to internal features of rocks grades IV and V (even in local but mostly controlling zones. With increasing attentions to the characteristics, mechanism and influences of engineering construction-triggered geohazards, it is crucial to fully understand the disturbance of these geohazards on project construction. A reasonable determination method in construction procedure, i.e. the shape of working face, the type of engineering support and the choice of feasible procedure, should be considered in order to mitigate the construction-triggered geohazards. Due to their high sensitivity to groundwater and in-situ stress, various UGBs exhibit hysteretic nature and failure modes. To give a complete understanding on the internal causes, the emphasis on advanced comprehensive geological forecasting and overall reinforcement treatment is therefore of more practical significance. Comprehensive evaluation of influential factors, identification of UGB, and measures of discontinuity dynamic controlling comprises the geoengineering condition evaluation and dynamic controlling method. In a case of a cut slope, the variations of UGBs and the impacts of key environmental factors are presented, where more severe construction-triggered geohazards emerged in construction stage than those predicted in design and field investigation stages. As a result, the weight ratios of different influential factors with respect to field investigation, design and construction are obtained.

  11. Method for Controlled Mitochondrial Perturbation during Phosphorus MRS in Children (United States)

    Cree-Green, Melanie; Newcomer, Bradley R.; Brown, Mark; Hull, Amber; West, Amy D.; Singel, Debra; Reusch, Jane E.B.; McFann, Kim; Regensteiner, Judith G.; Nadeau, Kristen J.


    Introduction Insulin resistance (IR) is increasingly prevalent in children, and may be related to muscle mitochondrial dysfunction, necessitating development of mitochondrial assessment techniques. Recent studies used 31Phosphorus magnetic resonance spectroscopy (31P-MRS), a non-invasive technique appealing for clinical research. 31P-MRS requires exercise at a precise percentage of maximum volitional contraction (MVC). MVC measurement in children, particularly with disease, is problematic due to variability in perception of effort and motivation. We therefore developed a method to predict MVC, using maximal calf muscle cross-sectional area (MCSA) to assure controlled and reproducible muscle metabolic perturbations. Methods Data were collected from 66 sedentary 12–20 year-olds. Plantar flexion-volitional MVC was assessed using a MRI-compatible exercise treadle device. MCSA of the calf muscles were measured from MRI images. Data from the first 26 participants were utilized to model the relationship between MVC and MCSA (predicted MVC = 24.763+0.0047*MCSA). This model was then applied to the subsequent 40 participants. Results Volitional vs. model-predicted mean MVC was 43.9±0.8 kg vs. 44.2±1.81 (P=0.90). 31P-MRS results when predicted and volitional MVC were similar showed expected changes during volitional MVC-based exercise. In contrast, volitional MVC was markedly lower than predicted in 4 participants, and produced minimal metabolic perturbation. Upon repeat testing, these individuals could perform their predicted MVC with coaching, which produced expected metabolic perturbations. Conclusions Compared to using MVC testing alone, utilizing MRI to predict muscle strength allows for a more accurate and standardized 31P-MRS protocol during exercise in children. This method overcomes a major obstacle in assessing mitochondrial function in youth. These studies have importance as we seek to determine the role of mitochondrial function in youth with IR and diabetes

  12. Modeling, control and optimization of water systems systems engineering methods for control and decision making tasks

    CERN Document Server


    This book provides essential background knowledge on the development of model-based real-world solutions in the field of control and decision making for water systems. It presents system engineering methods for modelling surface water and groundwater resources as well as water transportation systems (rivers, channels and pipelines). The models in turn provide information on both the water quantity (flow rates, water levels) of surface water and groundwater and on water quality. In addition, methods for modelling and predicting water demand are described. Sample applications of the models are presented, such as a water allocation decision support system for semi-arid regions, a multiple-criteria control model for run-of-river hydropower plants, and a supply network simulation for public services.

  13. Comparison of advanced distillation control methods. First annual report

    Energy Technology Data Exchange (ETDEWEB)

    Riggs, J.B.


    A detailed dynamic simulator of a propylene/propane (C{sub 3}) splitter, which was bench-marked against industrial data, has been used to compare dual composition control performance for a diagonal PI controller and several advanced controllers. The advanced controllers considered are dynamic matrix control (DMC), nonlinear process model based control, and artificial neutral networks. Each controller was tuned based upon setpoint changes in the overhead product composition using 50% changes in the impurity levels. Overall, there was not a great deal of difference in controller performance based upon the setpoint and disturbance tests. Periodic step changes in feed composition were also used to compare controller performance. In this case, oscillatory variations of the product composition were observed and the variabilities of the DC and nonlinear process model based controllers were substantially smaller than that of the PI controller. The sensitivity of each controller to the frequency of the periodic step changes in feed composition was also investigated.

  14. Battery control system for hybrid vehicle and method for controlling a hybrid vehicle battery (United States)

    Bockelmann, Thomas R [Battle Creek, MI; Hope, Mark E [Marshall, MI; Zou, Zhanjiang [Battle Creek, MI; Kang, Xiaosong [Battle Creek, MI


    A battery control system for hybrid vehicle includes a hybrid powertrain battery, a vehicle accessory battery, and a prime mover driven generator adapted to charge the vehicle accessory battery. A detecting arrangement is configured to monitor the vehicle accessory battery's state of charge. A controller is configured to activate the prime mover to drive the generator and recharge the vehicle accessory battery in response to the vehicle accessory battery's state of charge falling below a first predetermined level, or transfer electrical power from the hybrid powertrain battery to the vehicle accessory battery in response to the vehicle accessory battery's state of charge falling below a second predetermined level. The invention further includes a method for controlling a hybrid vehicle powertrain system.

  15. Comparison of advanced distillation control methods. First annual report

    Energy Technology Data Exchange (ETDEWEB)



    A detailed dynamic simulator of a propylene/propane (C3) splitter, which was bench-marked against industrial data, has been used to compare dual composition control performance for a diagonal PI controller and several advanced controllers. The advanced controllers considered are DMC, nonlinear process model based control, and articial neutral networks. Each controller was tuned based upon setpoint changes in the overhead product composition using 50% changes in the impurity levels. Overall, there was not a great deal of difference in controller performance based upon the setpoint and disturbance tests. Periodic step changes in feed composition were also used to compare controller performance. In this case, oscillatory variations of the product composition were observed and the variabilities of the DMC and nonlinear process model based controllers were substantially smaller than that of the PI controller. The sensitivity of each controller to the frequency of the periodic step changes in feed composition was also investigated.

  16. Systems and Methods for Derivative-Free Adaptive Control (United States)

    Yucelen, Tansel (Inventor); Kim, Kilsoo (Inventor); Calise, Anthony J. (Inventor)


    An adaptive control system is disclosed. The control system can control uncertain dynamic systems. The control system can employ one or more derivative-free adaptive control architectures. The control system can further employ one or more derivative-free weight update laws. The derivative-free weight update laws can comprise a time-varying estimate of an ideal vector of weights. The control system of the present invention can therefore quickly stabilize systems that undergo sudden changes in dynamics, caused by, for example, sudden changes in weight. Embodiments of the present invention can also provide a less complex control system than existing adaptive control systems. The control system can control aircraft and other dynamic systems, such as, for example, those with non-minimum phase dynamics.

  17. An Optimal Direct Control Method of Multilevel Inverters for Microgrid Applications

    DEFF Research Database (Denmark)

    Naderi Zarnaghi, Yahya; Hosseini, Seyed Hossein; Ghassem Zadeh, Saeed


    In this paper, an optimized current control method for multilevel inverter (MLI) is proposed to overcome harmonic current tracking inefficiency of previous methods. This control method is applicable for both islanded and grid-connected inverter-based Distributed Generation (DG) applications. It can...... be applied to voltage controlled as well as current controlled inverters. Having the advantages of current control methods like hysteresis band control, proportional-integral PI and Proportional + Resonant (PR) control methods, it overcomes disadvantages of these methods especially in harmonic reference...

  18. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    KAUST Repository

    Prest, Emmanuelle I.


    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  19. Biological stability of drinking water: controlling factors, methods and challenges

    Directory of Open Access Journals (Sweden)

    Emmanuelle ePrest


    Full Text Available Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g. development of opportunistic pathogens, aesthetic (e.g. deterioration of taste, odour, colour or operational (e.g. fouling or biocorrosion of pipes problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors such as (i type and concentration of available organic and inorganic nutrients, (ii type and concentration of residual disinfectant, (iii presence of predators such as protozoa and invertebrates, (iv environmental conditions such as water temperature, and (v spatial location of microorganisms (bulk water, sediment or biofilm. Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i existing knowledge on biological stability controlling factors and (ii how these factors are affected by drinking water production and distribution conditions. In addition, (iii the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discuss how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order to

  20. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges (United States)

    Prest, Emmanuelle I.; Hammes, Frederik; van Loosdrecht, Mark C. M.; Vrouwenvelder, Johannes S.


    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  1. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges. (United States)

    Prest, Emmanuelle I; Hammes, Frederik; van Loosdrecht, Mark C M; Vrouwenvelder, Johannes S


    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  2. Active vibration control for piezoelectricity cantilever beam: an adaptive feedforward control method (United States)

    Zhu, Qiao; Yue, Jun-Zhou; Liu, Wei-Qun; Wang, Xu-Dong; Chen, Jun; Hu, Guang-Di


    This work is focused on the active vibration control of piezoelectric cantilever beam, where an adaptive feedforward controller (AFC) is utilized to reject the vibration with unknown multiple frequencies. First, the experiment setup and its mathematical model are introduced. Due to that the channel between the disturbance and the vibration output is unknown in practice, a concept of equivalent input disturbance (EID) is employed to put an equivalent disturbance into the input channel. In this situation, the vibration control can be achieved by setting the control input be the identified EID. Then, for the EID with known multiple frequencies, the AFC is introduced to perfectly reject the vibration but is sensitive to the frequencies. In order to accurately identify the unknown frequencies of EID in presence of the random disturbances and un-modeled nonlinear dynamics, the time-frequency-analysis (TFA) method is employed to precisely identify the unknown frequencies. Consequently, a TFA-based AFC algorithm is proposed to the active vibration control with unknown frequencies. Finally, four cases are given to illustrate the efficiency of the proposed TFA-based AFC algorithm by experiment.

  3. Autonomous Navigation Motion Control of Mobile Robots using Hybrid System Control Method

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y.M. [Samsung Electronics Co., Ltd., Seoul (Korea); Lim, M.S. [Kyonggi Institute of Technology, Shihung (Korea); Lim, J.H. [Hanyang University, Seoul (Korea)


    This paper presents a framework of hybrid dynamic control systems for the motion control of wheeled mobile robot systems with nonholonomic constraints. The hybrid control system has the 3-layered hierarchical structure: digital automata for the higher process, mobile robot system for the lower process, and the interface as the interaction process between the continuous dynamics and the discrete dynamics. In the hybrid control architecture of mobile robot, the continuous dynamics of mobile robots are modeled by the switched systems. The abstract model and digital automata for the motion control are developed. In high level, the discrete states are defined by using the sensor-based search windows and the reference motions of a mobile robot in low level are specified in the abstracted motions. The mobile robots can perform both the motion planning and autonomous maneuvering with obstacle avoidance in indoor navigation problem. Simulation and experimental results show that hybrid system approach is an effective method for the autonomous maneuvering in indoor environments. (author). 13 refs., 13 figs., 1 tab.

  4. Design and experiments of the fuel control method for the scramjet ...

    Indian Academy of Sciences (India)

    The control method is one of the key application technologies of the engine. And the core of the scramjet control system is the fuel-based control method. The design and the experimental verification of the scramjet fuel-based control method were mainly carried out in this paper. The correlation between the engine thrust, ...

  5. Efforts to control mites on Iberian ham by physical methods. (United States)

    García, Nazaret


    This study is aimed at the development of a method for integrated mite control in the industrial production of Iberian and Alentejan ham. The investigations were carried out on the premises of five factories in the southwest of the Iberian Peninsula. Tyrophagus longior was predominant on hams in the drying rooms, Tyrophagus putrescentiae in cellars, while Tyrolichus casei was observed only in one factory, together with Melichares dendriticus (Acari: Ascidae), a predator of tyroglyphids. Relative humidity levels below 60% reduced the growth of mites on the ham surface, but these conditions forced the mites to seek refuge: T. putrescentiae and T. casei were found in cavities inside the ham. At the end of the experimental curing period, 11% of the hams were totally disintegrated by mite damage inside. Mites survived high-temperature treatments which are detrimental to the hams: 71 degrees C, 11 min; 57 degrees C, 30 min and 40 degrees C, 96 h. They also survived a long low-humidity period: 1 month at 18 degrees C and 32% R.H.

  6. Control of inhomogeneous materials strength by method of acoustic emission

    Directory of Open Access Journals (Sweden)

    В. В. Носов


    Full Text Available The ambiguous connection between the results of acoustic emission control and the strength of materials makes acoustic-emission diagnosis ineffective and actualizes the problem of strength and metrological heterogeneity. Inhomogeneity is some deviation from a certain norm. The real object is always heterogeneous, homogeneity is an assumption that simplifies the image of the object and the solution of the tasks associated with it. The need to consider heterogeneity is due to the need to clarify a particular task and is a transition to a more complex level of research. Accounting for heterogeneity requires the definition of its type, criterion and method of evaluation. The type of heterogeneity depends on the problem being solved and should be related to the property that determines the function of the real object, the criterion should be informative, and the way of its evaluation is non-destructive. The complexity of predicting the behavior of heterogeneous materials necessitates the modeling of the destructive process that determines the operability, the formulation of the inhomogeneity criterion, the interpretation of the Kaiser effect, as showing inhomogeneity of the phenomenon of non-reproduction of acoustic emission (AE activity upon repeated loading of the examined object.The article gives an example of modeling strength and metrological heterogeneity, analyzes and estimates the informative effect of the Kaiser effect on the danger degree of state of diagnosed object from the positions of the micromechanical model of time dependencies of AE parameters recorded during loading of structural materials and technical objects.

  7. FPGA Based Control Method for Three Phase BLDC Motor

    National Research Council Canada - National Science Library

    Suneeta Suneeta; R Srinivasan; Ram Sagar


    .... Speed Control of BLDC motor using PIC microcontrollers requires more hardware, and with the availability of FPGA versatile features motivated to develop a cost effective and reliable control with variable speed range...

  8. Evolutionary Tuning Method for PID Controller Parameters of a Cruise Control System Using Metamodeling

    Directory of Open Access Journals (Sweden)

    M. N. Ab Malek


    Full Text Available For long time the optimization of controller parameters uses the well-known classical method such as the Ziegler-Nichols and the Cohen-Coon tuning techniques. Despite its effectiveness, these off-line tuning techniques can be time consuming especially for a case of complex nonlinear system. This paper attempts to show a great deal on how Metamodeling techniques can be utilized to tune the PID controller parameters quickly. Note that the plant use in this study is the cruise control system with 2 different models, which are the linear model and the nonlinear model. The difference between both models is that the disturbances were taken into consideration for the nonlinear model, but in the linear model the disturbances were assumed as zero. The Radial Basis Function Neural Network Metamodel is able to prove that it can minimize the time in tuning process as it is able to give a good approximation to the optimum controller parameters in both models of this system.

  9. Methodical Grounds of Managing the Product Quality Control


    Shapoval Olena A.


    The article analyses the modern state of products quality control management. It justifies a necessity of organisation of the quality control system under conditions of uninterrupted flow line production. It reveals problems connected with a low level of the products quality control management. It forms a set of factors of internal and external environments, which should be taken into account in the process of selection of a type of managerial actions by the products quality control. It consi...

  10. Methods of Synthesis of Automatic Control Systems with Delay

    Directory of Open Access Journals (Sweden)

    Aliaksandr Lapeta


    Full Text Available The paper investigates the procedure for introduction of systems containing delay elements. Shortcomings and difficulties in the synthesis of regulators and precompensators of control systems with delays in output and control channel where determined. The author focused on two approaches for the formation of promatrix and synthesis of control systems, considering the factor of delay.

  11. An improved droop control method for multi-terminal VSC-HVDC converter stations

    DEFF Research Database (Denmark)

    Wang, Hao; Wang, Yue; Duan, Guozhao


    of smart grids. However, it is still a problem to control the converter to achieve the function of each AC system sharing the reserve capacity of the entire network. This paper proposes an improved control strategy based on the slope control of the DC voltage and AC frequency (V-f slope control), in which...... the virtual inertia is introduced. This method can ensure that each AC sub-system shares the primary frequency control function. Additionally, with the new control method, it is easy to apply the secondary frequency control method of traditional AC systems to AC/DC hybrid systems to achieve the steady control...... of the DC voltage and AC frequency of the whole system. Most importantly, the new control method is better than the traditional control method in terms of dynamic performance. In this paper, a new control method is proposed, and the simulation model has been established in Matlab/Simulink to verify...

  12. New Concepts and methods for developing shop floor control systems

    DEFF Research Database (Denmark)

    Lynggaard, Hans Jørgen; Bilberg, Arne; Alting, Leo


    control systems by the use of enablers, a generic cell control data model and an architecture has been defined. Further an engineering methodology is defined. It is concluded that cell control technology provides for increased performance in production systems, and that the cell control engineering...... concept reduces the effort for providing and operating high quality and high functionality cell control solutions for the industry. The plans for the next generation industrial shop floor and cell controllers are to develop new concepts based on more distributed systems, which are more robust and agile...... with respect to changing demands, technological advances and daily operations. The scope of these systems are a network of co-operating cells as opposed to individually operated cells which are co-ordinated in a traditionally (hierarchical planning) manner. This new approach raises new demands...

  13. Control and optimization system and method for chemical looping processes (United States)

    Lou, Xinsheng; Joshi, Abhinaya; Lei, Hao


    A control system for optimizing a chemical loop system includes one or more sensors for measuring one or more parameters in a chemical loop. The sensors are disposed on or in a conduit positioned in the chemical loop. The sensors generate one or more data signals representative of an amount of solids in the conduit. The control system includes a data acquisition system in communication with the sensors and a controller in communication with the data acquisition system. The data acquisition system receives the data signals and the controller generates the control signals. The controller is in communication with one or more valves positioned in the chemical loop. The valves are configured to regulate a flow of the solids through the chemical loop.

  14. Barrier Methods of Birth Control: Spermicide, Condom, Sponge, Diaphragm, and Cervical Cap (United States)

    ... ACOG Barrier Methods of Birth Control: Spermicide, Condom, Sponge, Diaphragm, and Cervical Cap Home For Patients Search ... 2016 Barrier Methods of Birth Control: Spermicide, Condom, Sponge, Diaphragm, and Cervical Cap This product is undergoing ...

  15. A nonlinear control method for the electromagnetic suspension system of the maglev train

    National Research Council Canada - National Science Library

    Xu, Junqi; Zhou, Yuan

    ... s. The proposed method has a faster response and stronger robustness. With a designed bi-DSP suspension controller, this nonlinear control method was implemented on the Shanghai Urban Maglev Test Line (SUMTL...

  16. Engineering models and methods for industrial cell control

    DEFF Research Database (Denmark)

    Lynggaard, Hans Jørgen Birk; Alting, Leo


    control and monitor-ing systems for production cells. The project participants are The Danish Academy of Technical Sciences, the Institute of Manufacturing Engineering at the Technical University of Denmark and ODENSE STEEL SHIPYARD Ltd.The manufacturing environment and the current practice...... SHIPYARD.It is concluded that cell control technology provides for increased performance in production systems, and that the Cell Control Engineering concept reduces the effort for providing and operating high quality and high functionality cell control solutions for the industry....

  17. Control system and method for a hybrid electric vehicle (United States)

    Phillips, Anthony Mark; Blankenship, John Richard; Bailey, Kathleen Ellen; Jankovic, Miroslava


    A vehicle system controller (20) is presented for a LSR parallel hybrid electric vehicle having an engine (10), a motor (12), wheels (14), a transmission (16) and a battery (18). The vehicle system controller (20) has a state machine having a plurality of predefined states (22-32) that represent operating modes for the vehicle. A set of rules is defined for controlling the transition between any two states in the state machine. The states (22-32) are prioritized according to driver demands, energy management concerns and system fault occurrences. The vehicle system controller (20) controls the transitions from a lower priority state to a higher priority state based on the set of rules. In addition, the vehicle system controller (20) will control a transition to a lower state from a higher state when the conditions no longer warrant staying in the current state. A unique set of output commands is defined for each state for the purpose of controlling lower level subsystem controllers. These commands serve to achieve the desire vehicle functionality within each state and insure smooth transitions between states.

  18. Analysis of balance control methods based on inverted pendulum for legged robots

    Directory of Open Access Journals (Sweden)

    Denisov Alexander


    Full Text Available Methods of balance control for a legged robot, the model of which is presented as a two-section inverted pendulum, are considered. The following balance methods for humanoid robots are analysed: the parallel algorithm of the network operator method; the method of natural synergies; the method of fuzzy control, the spherical inverted pendulum mode, a dual length linear inverted pendulum method. The best of these methods will be used in the development of the Russian anthropomorphic robot Antares.

  19. Analytical one parameter method for PID motion controller settings

    NARCIS (Netherlands)

    van Dijk, Johannes; Aarts, Ronald G.K.M.


    In this paper analytical expressions for PID-controllers settings for electromechanical motion systems are presented. It will be shown that by an adequate frequency domain oriented parametrization, the parameters of a PID-controller are analytically dependent on one variable only, the cross-over

  20. Traditional methods of social control in Afikpo north local ...

    African Journals Online (AJOL)

    This paper examined the traditional social control mechanisms in Afikpo North LGA of Ebonyi state, south eastern Nigeria. The rising trend in extraneous crimes and vices like kidnapping, baby factories, drug peddling among others seem to be overwhelming for modern social control mechanisms. This has lent credence to ...

  1. Adherence to two methods of education and metabolic control in ...

    African Journals Online (AJOL)

    BACKGROUND: Education in diabetes optimizes metabolic control, prevents acute and chronic complications, and improves quality of life. Our main objective was to evaluate if a better metabolic control is achieved in diabetic patients undergoing a program of intensive interactive care than in those with traditional care and ...

  2. Quality control methods in accelerometer data processing: identifying extreme counts.

    Directory of Open Access Journals (Sweden)

    Carly Rich

    Full Text Available Accelerometers are designed to measure plausible human activity, however extremely high count values (EHCV have been recorded in large-scale studies. Using population data, we develop methodological principles for establishing an EHCV threshold, propose a threshold to define EHCV in the ActiGraph GT1M, determine occurrences of EHCV in a large-scale study, identify device-specific error values, and investigate the influence of varying EHCV thresholds on daily vigorous PA (VPA.We estimated quantiles to analyse the distribution of all accelerometer positive count values obtained from 9005 seven-year old children participating in the UK Millennium Cohort Study. A threshold to identify EHCV was derived by differentiating the quantile function. Data were screened for device-specific error count values and EHCV, and a sensitivity analysis conducted to compare daily VPA estimates using three approaches to accounting for EHCV.Using our proposed threshold of ≥ 11,715 counts/minute to identify EHCV, we found that only 0.7% of all non-zero counts measured in MCS children were EHCV; in 99.7% of these children, EHCV comprised < 1% of total non-zero counts. Only 11 MCS children (0.12% of sample returned accelerometers that contained negative counts; out of 237 such values, 211 counts were equal to -32,768 in one child. The medians of daily minutes spent in VPA obtained without excluding EHCV, and when using a higher threshold (≥19,442 counts/minute were, respectively, 6.2% and 4.6% higher than when using our threshold (6.5 minutes; p<0.0001.Quality control processes should be undertaken during accelerometer fieldwork and prior to analysing data to identify monitors recording error values and EHCV. The proposed threshold will improve the validity of VPA estimates in children's studies using the ActiGraph GT1M by ensuring only plausible data are analysed. These methods can be applied to define appropriate EHCV thresholds for different accelerometer models.

  3. Computer-Aided Design Methods for Model-Based Nonlinear Engine Control Systems Project (United States)

    National Aeronautics and Space Administration — Traditional design methods for aircraft turbine engine control systems have relied on the use of linearized models and linear control theory. While these controllers...

  4. Comparison of model reference and map based control method for vehicle stability enhancement

    NARCIS (Netherlands)

    Baek, S.; Son, M.; Song, J.; Boo, K.; Kim, H.


    A map based controller method to improve a vehicle lateral stability is proposed in this study and compared with the conventional method, a model referenced controller. A model referenced controller to determine compensated yaw moment uses the sliding mode method, but the proposed map based

  5. Coupling order release methods with autonomous control methods – an assessment of potentials by literature review and discrete event simulation

    Directory of Open Access Journals (Sweden)

    Sebastian Grundstein


    Full Text Available Production planning and control faces increasing uncertainty, dynamics and complexity. Autonomous control methods proved themselves as a promising approach for coping with these challenges. However, there is a lack of knowledge regarding the interaction between autonomous control and precedent functions of production planning and control. In particular, up to now previous research has paid no attention to the influence of order release methods on the efficiency of autonomous control methods. Thereby, many researchers over the last decades provided evidence that the order release function has great influence on the logistic objective achievement in conventional production systems. Therefore, this paper examines the influence of order release methods on the efficiency of autonomous control methods by both theoretic evaluation and discrete event simulation. The simulation results indicate an overall high influence. Moreover, the logistic performance differs considerably depending on the implemented order release methods and the combinations of order release methods with autonomous control methods. The findings highlight demand for further research in this field.

  6. Actively Controlled Structures Theory. Volume 1. Theory of Design Methods (United States)


    R.E., "Contributions to the Theory of Optimal Control," Bol. Soc. Mat. Mexicana , Second Ser., Vol. 5, pp. 102-114, 1960; Proceedings of the Mexico...of these critical modas is weak and excessive energy is required. Thus, it is better to consider these two modes as having identical frequencies, and...SIAM Control. Series A, Vol. 1, No. 2, pp. 152-192, 1963. 6. Kaiman, R.E., "Contributions to the Theory of Optimal Control," Bol. Soc. Mat. Mexicana

  7. Chemical and ecological control methods for Epitrix spp.

    Directory of Open Access Journals (Sweden)

    A. G. S. Cuthbertson


    Full Text Available Very little information exists in regards to the control options available for potato flea beetles, Epitrix spp. This short review covers both chemical and ecological options currently available for control of Epitrix spp. Synthetic pyrethroids are the weapon of choice for the beetles. However, the impetus in integrated pest management is to do timely (early-season applications with something harsh which will give long-term protection at a time when there are not a lot of beneficials in the field. Finding the balance for control of Epitrix spp. is proving difficult.

  8. Methods and compositions for controlling gene expression by RNA processing

    Energy Technology Data Exchange (ETDEWEB)

    Doudna, Jennifer A.; Qi, Lei S.; Haurwitz, Rachel E.; Arkin, Adam P.


    The present disclosure provides nucleic acids encoding an RNA recognition sequence positioned proximal to an insertion site for the insertion of a sequence of interest; and host cells genetically modified with the nucleic acids. The present disclosure also provides methods of modifying the activity of a target RNA, and kits and compositions for carrying out the methods.

  9. Implementation of Control Design Methods into Matlab Environment


    Matušů, Radek; Prokop, Roman


    The main aim of this chapter is to present two simple and freely downloadable Matlab programs which allow user-friendly work for two selected specific control design issues by means of Graphical User Interface (GUI).

  10. Use of Modern Birth Control Methods Among Rural Communities in ...

    African Journals Online (AJOL)


    07. 8. Illingworth, B. Birth control in developing nations. Planned Parenthood. www.planned- Visited 20/3/07. 9. Lacey, L. et al. Decentralization of Population. Programmes in Sub-Sahara Africa: Concepts and. Issues. Options.


    DEFF Research Database (Denmark)


    A digital switching power amplifier with Multivariable Enhanced Cascade Controlled (MECC) includes a modulator, a switching power stage and a low pass filter. In the first preferred embodiment an enhanced cascade control structure local to the switching power stage is added, characterised by havi...... and feedback path A to determine stable self-oscillating conditions. An implemented 250W example MECC digital power amplifier has proven superior performance in terms of audio performance (0.005 % distortion, 115 dB dynamic range) and efficiency (92 %).......A digital switching power amplifier with Multivariable Enhanced Cascade Controlled (MECC) includes a modulator, a switching power stage and a low pass filter. In the first preferred embodiment an enhanced cascade control structure local to the switching power stage is added, characterised by having...

  12. Optimal Control with Time Delays via the Penalty Method

    Directory of Open Access Journals (Sweden)

    Mohammed Benharrat


    Full Text Available We prove necessary optimality conditions of Euler-Lagrange type for a problem of the calculus of variations with time delays, where the delay in the unknown function is different from the delay in its derivative. Then, a more general optimal control problem with time delays is considered. Main result gives a convergence theorem, allowing us to obtain a solution to the delayed optimal control problem by considering a sequence of delayed problems of the calculus of variations.

  13. Methods for Reachability-based Hybrid Controller Design (United States)


    reachability and safe sets computation for discrete time stochastic hybrid systems. In Proceedings of the 45th IEEE Conference on Decision and Control. San ...imperfect information. In Automata, Languages and Programming (S. Albers, A. Marchetti-Spaccamela, Y. Matias , S. Nikoletseas and W. Thomas, Eds.). Vol. multi-player pursuit and evasion game. In Proceedings of the AIAA Conference on Guidance, Navigation and Control. San Francisco, CA. Jin, Z., Shima

  14. A Unified Weighted Least Norm Method for Redundant Manipulator Control

    Directory of Open Access Journals (Sweden)

    Peng Chen


    Full Text Available A redundant manipulator usually has multiple kinematic solutions at the velocity level and can be used to optimize other criteria. Although the pseudo inverse of the Jacobian matrix generates a solution with the least 2 norm (LN, it does not consider other constraints imposed by the system or the environment. The general weighted least norm (GWLN method handles these general constraints via the concept of virtual joints, but this is not always feasible when the number of constraints exceeds the degrees of freedom. This paper proposes a unified weighted least norm method (UWLN to unify the LN and the GWLN methods. The UWLN method merges the constraint tasks into a quadratic criterion that poses no limitations on the number of constraint tasks. It also generates a least 2 norm solution when all constraints are deactivated, thereby unifying the LN and GWLN methods. A comparative simulation on a 7-DoF planar manipulator demonstrates the validity of the algorithm.

  15. Force control compensation method with variable load stiffness and damping of the hydraulic drive unit force control system (United States)

    Kong, Xiangdong; Ba, Kaixian; Yu, Bin; Cao, Yuan; Zhu, Qixin; Zhao, Hualong


    Each joint of hydraulic drive quadruped robot is driven by the hydraulic drive unit (HDU), and the contacting between the robot foot end and the ground is complex and variable, which increases the difficulty of force control inevitably. In the recent years, although many scholars researched some control methods such as disturbance rejection control, parameter self-adaptive control, impedance control and so on, to improve the force control performance of HDU, the robustness of the force control still needs improving. Therefore, how to simulate the complex and variable load characteristics of the environment structure and how to ensure HDU having excellent force control performance with the complex and variable load characteristics are key issues to be solved in this paper. The force control system mathematic model of HDU is established by the mechanism modeling method, and the theoretical models of a novel force control compensation method and a load characteristics simulation method under different environment structures are derived, considering the dynamic characteristics of the load stiffness and the load damping under different environment structures. Then, simulation effects of the variable load stiffness and load damping under the step and sinusoidal load force are analyzed experimentally on the HDU force control performance test platform, which provides the foundation for the force control compensation experiment research. In addition, the optimized PID control parameters are designed to make the HDU have better force control performance with suitable load stiffness and load damping, under which the force control compensation method is introduced, and the robustness of the force control system with several constant load characteristics and the variable load characteristics respectively are comparatively analyzed by experiment. The research results indicate that if the load characteristics are known, the force control compensation method presented in this

  16. Control rod worth calculations using deterministic and stochastic methods

    Energy Technology Data Exchange (ETDEWEB)

    Varvayanni, M. [NCSR ' DEMOKRITOS' , PO Box 60228, 15310 Aghia Paraskevi (Greece); Savva, P., E-mail: melina@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PO Box 60228, 15310 Aghia Paraskevi (Greece); Catsaros, N. [NCSR ' DEMOKRITOS' , PO Box 60228, 15310 Aghia Paraskevi (Greece)


    Knowledge of the efficiency of a control rod to absorb excess reactivity in a nuclear reactor, i.e. knowledge of its reactivity worth, is very important from many points of view. These include the analysis and the assessment of the shutdown margin of new core configurations (upgrade, conversion, refuelling, etc.) as well as several operational needs, such as calibration of the control rods, e.g. in case that reactivity insertion experiments are planned. The control rod worth can be assessed either experimentally or theoretically, mainly through the utilization of neutronic codes. In the present work two different theoretical approaches, i.e. a deterministic and a stochastic one are used for the estimation of the integral and the differential worth of two control rods utilized in the Greek Research Reactor (GRR-1). For the deterministic approach the neutronics code system SCALE (modules NITAWL/XSDRNPM) and CITATION is used, while the stochastic one is made using the Monte Carlo code TRIPOLI. Both approaches follow the procedure of reactivity insertion steps and their results are tested against measurements conducted in the reactor. The goal of this work is to examine the capability of a deterministic code system to reliably simulate the worth of a control rod, based also on comparisons with the detailed Monte Carlo simulation, while various options are tested with respect to the deterministic results' reliability.

  17. A new method to minimize the chattering phenomenon in sliding mode control based on intelligent control for induction motor drives

    Directory of Open Access Journals (Sweden)

    Bendaas Ismail


    Full Text Available This paper presents new method toward the design of hybrid control with sliding-mode (SMC plus fuzzy logic control (FLC for induction motors. As the variations of both control system parameters and operating conditions occur, the conventional control methods may not be satisfied further. Sliding mode control is robust with respect to both induction motor parameter variations and external disturbances. By embedding a fuzzy logic control into the sliding mode control, the chattering (torque-ripple problem with varying parameters, which are the main disadvantage in sliding-mode control, can be suppressed, Simulation results of the proposed control theme present good dynamic and steady-state performances as compared to the classical SMC from aspects for torque-ripple minimization, the quick dynamic torque response and robustness to disturbance and variation of parameters.

  18. System and method for controlling a vision guided robot assembly

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yhu-Tin; Daro, Timothy; Abell, Jeffrey A.; Turner, III, Raymond D.; Casoli, Daniel J.


    A method includes the following steps: actuating a robotic arm to perform an action at a start position; moving the robotic arm from the start position toward a first position; determining from a vision process method if a first part from the first position will be ready to be subjected to a first action by the robotic arm once the robotic arm reaches the first position; commencing the execution of the visual processing method for determining the position deviation of the second part from the second position and the readiness of the second part to be subjected to a second action by the robotic arm once the robotic arm reaches the second position; and performing a first action on the first part using the robotic arm with the position deviation of the first part from the first position predetermined by the vision process method.

  19. Tandem robot control system and method for controlling mobile robots in tandem (United States)

    Hayward, David R.; Buttz, James H.; Shirey, David L.


    A control system for controlling mobile robots provides a way to control mobile robots, connected in tandem with coupling devices, to navigate across difficult terrain or in closed spaces. The mobile robots can be controlled cooperatively as a coupled system in linked mode or controlled individually as separate robots.

  20. Predistortion control device and method, assembly including a predistortion control device

    NARCIS (Netherlands)

    Kokkeler, Andre B.J.


    A predistortion control device (1). The device has a first predistortion control input connectable to a power amplifier output (21); a second predistortion control input (11) connectable to a signal contact of a predistortion device; and a predistortion control output (12) connectable to a control

  1. Methods and Tools for Profiling and Control of Distributed Systems

    Directory of Open Access Journals (Sweden)

    Sukharev Roman


    Full Text Available The article analyzes and standardizes methods for profiling distributed systems that focus on simulation to conduct experiments and build a graph model of the system. The theory of queueing networks is used for simulation modeling of distributed systems, receiving and processing user requests. To automate the above method of profiling distributed systems the software application was developed with a modular structure and similar to a SCADA-system.

  2. Marzipan: polymerase chain reaction-driven methods for authenticity control. (United States)

    Brüning, Philipp; Haase, Ilka; Matissek, Reinhard; Fischer, Markus


    According to German food guidelines, almonds are the only oilseed ingredient allowed for the production of marzipan. Persipan is a marzipan surrogate in which the almonds are replaced by apricot or peach kernels. Cross-contamination of marzipan products with persipan may occur if both products are produced using the same production line. Adulterations or dilutions, respectively, of marzipan with other plant-derived products, for example, lupine or pea, have also been found. Almond and apricot plants are closely related. Consequently, classical analytical methods for the identification/differentiation often fail or are not sensitive enough to quantify apricot concentrations below 1%. Polymerase chain reaction (PCR)-based methods have been shown to enable the differentiation of closely related plant species in the past. These methods are characterized by high specificity and low detection limits. Isolation methods were developed and evaluated especially with respect to the matrix marzipan in terms of yield, purity, integrity, and amplificability of the isolated DNA. For the reliable detection of apricot, peach, pea, bean, lupine, soy, cashew, pistachio, and chickpea, qualitative standard and duplex PCR methods were developed and established. The applicability of these methods was tested by cross-reaction studies and analysis of spiked raw pastes. Contaminations at the level of 0.1% could be detected.

  3. Research on the displacement control method of asynchronous modular contactor (United States)

    He, Gong; Ming, Zong


    Ac contactor is a kind of low voltage electrical appliances with large usage and wide application. Because of the frequent operation, contactor life must be long enough to ensure the reliable operation of power system. The electrical life of the contactor, as the key to affect the service life of the contactor, is mainly affected by the arc developed in the breaking and closing course. This paper concentrates on a new type of asynchronous modular contactor. To get the contactor movement characteristics, the dynamic model of the electromagnetic system is established by MATLAB/SIMULINK. Then, according to the displacement curve of contactor, the breaking process and closing process is planned. The thought of closed loop control, by adjusting the parameters of PID controller, enables the contactor to operate as the planning displacement curve. In addition, to achieve no arc or micro arc breaking and no bounce or micro bounce closing , a displacement closed loop control system for contactor is designed.

  4. Optimal Control Method for Wind Farm to Support Temporary Primary Frequency Control with Minimized Wind Energy Cost

    DEFF Research Database (Denmark)

    Wang, Haijiao; Chen, Zhe; Jiang, Quanyuan


    This study proposes an optimal control method for variable speed wind turbines (VSWTs) based wind farm (WF) to support temporary primary frequency control. This control method consists of two layers: temporary frequency support control (TFSC) of the VSWT, and temporary support power optimal...... dispatch (TSPOD) of the WF. With TFSC, the VSWT could temporarily provide extra power to support system frequency under varying and wide-range wind speed. In the WF control centre, TSPOD optimally dispatches the frequency support power orders to the VSWTs that operate under different wind speeds, minimises...... the wind energy cost of frequency support, and satisfies the support capabilities of the VSWTs. The effectiveness of the whole control method is verified in the IEEE-RTS built in MATLABSimulink, and compared with a published de-loading method....

  5. Method and apparatus for controlling accidental releases of tritium (United States)

    Galloway, Terry R. [Berkeley, CA


    An improvement in a tritium control system based on a catalytic oxidation reactor wherein accidental releases of tritium into room air are controlled by flooding the catalytic oxidation reactor with hydrogen when the tritium concentration in the room air exceeds a specified limit. The sudden flooding with hydrogen heats the catalyst to a high temperature within seconds, thereby greatly increasing the catalytic oxidation rate of tritium to tritiated water vapor. Thus, the catalyst is heated only when needed. In addition to the heating effect, the hydrogen flow also swamps the tritium and further reduces the tritium release.

  6. Efficacy of cultural methods in the control of Rhizoctonia solani ...

    African Journals Online (AJOL)

    The efficacy of the various cultural strategies both singly and in combination on the Rhizoctonia damping off management was compared with the conventional disease control involving chemical fumigation with metham sodium and two chemical seed dressers (pencycuron, thiram, imidacloprid) and (captafol) as the ...

  7. Power control apparatus and methods for electric vehicles (United States)

    Gadh, Rajit; Chung, Ching-Yen; Chu, Chi-Cheng; Qiu, Li


    Electric vehicle (EV) charging apparatus and methods are described which allow the sharing of charge current between multiple vehicles connected to a single source of charging energy. In addition, this charge sharing can be performed in a grid-friendly manner by lowering current supplied to EVs when necessary in order to satisfy the needs of the grid, or building operator. The apparatus and methods can be integrated into charging stations or can be implemented with a middle-man approach in which a multiple EV charging box, which includes an EV emulator and multiple pilot signal generation circuits, is coupled to a single EV charge station.

  8. Advanced Control and Protection system Design Methods for Modular HTGRs

    Energy Technology Data Exchange (ETDEWEB)

    Ball, Sydney J [ORNL; Wilson Jr, Thomas L [ORNL; Wood, Richard Thomas [ORNL


    The project supported the Nuclear Regulatory Commission (NRC) in identifying and evaluating the regulatory implications concerning the control and protection systems proposed for use in the Department of Energy's (DOE) Next-Generation Nuclear Plant (NGNP). The NGNP, using modular high-temperature gas-cooled reactor (HTGR) technology, is to provide commercial industries with electricity and high-temperature process heat for industrial processes such as hydrogen production. Process heat temperatures range from 700 to 950 C, and for the upper range of these operation temperatures, the modular HTGR is sometimes referred to as the Very High Temperature Reactor or VHTR. Initial NGNP designs are for operation in the lower temperature range. The defining safety characteristic of the modular HTGR is that its primary defense against serious accidents is to be achieved through its inherent properties of the fuel and core. Because of its strong negative temperature coefficient of reactivity and the capability of the fuel to withstand high temperatures, fast-acting active safety systems or prompt operator actions should not be required to prevent significant fuel failure and fission product release. The plant is designed such that its inherent features should provide adequate protection despite operational errors or equipment failure. Figure 1 shows an example modular HTGR layout (prismatic core version), where its inlet coolant enters the reactor vessel at the bottom, traversing up the sides to the top plenum, down-flow through an annular core, and exiting from the lower plenum (hot duct). This research provided NRC staff with (a) insights and knowledge about the control and protection systems for the NGNP and VHTR, (b) information on the technologies/approaches under consideration for use in the reactor and process heat applications, (c) guidelines for the design of highly integrated control rooms, (d) consideration for modeling of control and protection system designs

  9. A method for controlling the excitation of a synchronous machine

    Energy Technology Data Exchange (ETDEWEB)

    Blokhin, V.F.; Rosman, L.V.


    The method lies in the fact that in the operational process the transfer functions of the automatic excitation regulation are changed. In order to increase the quality of regulation, the status of the current limiter is identified and the transfer functions are changed based on this.

  10. New methods for moisture control of high-performance concrete

    DEFF Research Database (Denmark)

    Kovler, Konstantin; Jensen, Ole Mejlhede; Falikman, Vyacheslav


    Curing of concrete by both external (conventional) and internal methods is reviewed and analyzed. The focus is given on the mitigation of autogenous shrinkage of low water-to-cementitious materials ratio concrete by means of internal curing. The concepts of internal curing are based on using pre-...... of professionals who work for them. The differences between conventional methods of external curing and novel methods of internal curing are described. It is concluded that proper curing is a key factor to achieve durable concrete.......Curing of concrete by both external (conventional) and internal methods is reviewed and analyzed. The focus is given on the mitigation of autogenous shrinkage of low water-to-cementitious materials ratio concrete by means of internal curing. The concepts of internal curing are based on using pre......-soaked lightweight aggregate, super-absorbent polymers or water-soluble chemicals, which reduce water evaporation (so called "internal sealing"). These concepts have been suggested in the 90s, but still are not popular among users, engineers, contractors, concrete suppliers, researchers, and the rest...

  11. Advanced Control Methods for Optimization of Arc Welding

    DEFF Research Database (Denmark)

    Thomsen, J. S.

    Gas Metal Arc Welding (GMAW) is a proces used for joining pieces of metal. Probably, the GMAW process is the most successful and widely used welding method in the industry today. A key issue in welding is the quality of the welds produced. The quality of a weld is influenced by several factors in...

  12. Reticulation of Aqueous Polyurethane Systems Controlled by DSC Method

    Directory of Open Access Journals (Sweden)

    Jakov Stamenkovic


    Full Text Available The DSC method has been employed to monitor the kinetics of reticulation ofaqueous polyurethane systems without catalysts, and with the commercial catalyst of zirconium(CAT®XC-6212 and the highly selective manganese catalyst, the complex Mn(III-diacetylacetonemaleinate (MAM. Among the polyol components, the acrylic emulsions wereused for reticulation in this research, and as suitable reticulation agents the water emulsiblealiphatic polyisocyanates based on hexamethylendoisocyanate with the different contents ofNCO-groups were employed. On the basis of DSC analysis, applying the methods of Kissinger,Freeman-Carroll and Crane-Ellerstein the pseudo kinetic parameters of the reticulation reactionof aqueous systems were determined. The temperature of the examination ranged from 50oC to450oC with the heat rate of 0.5oC/min. The reduction of the activation energy and the increaseof the standard deviation indicate the catalytic action of the selective catalysts of zirconium andmanganese. The impact of the catalysts on the reduction of the activation energy is thestrongest when using the catalysts of manganese and applying all the three afore-said methods.The least aberrations among the stated methods in defining the kinetic parameters wereobtained by using the manganese catalyst.

  13. A Method to Establish Stimulus Control and Compliance with Instructions (United States)

    Borgen, John G.; Mace, F. Charles; Cavanaugh, Brenna M.; Shamlian, Kenneth; Lit, Keith R.; Wilson, Jillian B.; Trauschke, Stephanie L.


    We evaluated a unique procedure to establish compliance with instructions in four young children diagnosed with autism spectrum disorder (ASD) who had low levels of compliance. Our procedure included methods to establish a novel therapist as a source of positive reinforcement, reliably evoke orienting responses to the therapist, increase the…

  14. Numerical analysis using state space method for vibration control of ...

    African Journals Online (AJOL)

    ... on sagged bridges and car moving on road humps. The paper also presents the comparison of performance of both the dampers for the two cases. State space method has been employed for the numerical analysis of the study. It is found that the amplitude of displacements is reduced considerably by the employment of ...

  15. Methods of evaluating performance in controlling marketing,activities


    Codruţa Dura


    There are specific methods for assessing and improving the effectiveness of a marketing strategy. A marketer should state in the marketing plan what a marketing strategy is supposed to accomplish. These statements should set forth performance standards, which usually are stated in terms of profits, sales, or costs

  16. Interactions Validation Methods for Training Resources Control Engine Development

    Directory of Open Access Journals (Sweden)

    Marcin Waldemar Bernaś


    Full Text Available The training courseware complexity proper selection is one of the most difficult factors looking from an intelligent application engine development. The application needs individual settings, the most relevant for the application structure matching to the users' individual expectations. What  is more,  the  obtained  structure  allows  controlling  dynamically  the  application within a time it is used. The application units description with their controlling functions allow joining the database components into individual composition of the courseware. The paper in-troduces several aspects of distance learning resources development, fulfilling the demanding assumptions of the interactive training units.

  17. Novel methods of utilizing Jitter for Network Congestion Control

    Directory of Open Access Journals (Sweden)



    Full Text Available This paper proposes a novel paradigm for network congestion control. Instead of perpetual conflict as in TCP, a proof-of-concept first-ever protocol enabling inter-flow communication without infrastructure support thru a side channel constructed on generic FIFO queue behaviour is presented. This enables independent flows passing thru the same bottleneck queue to communicate and achieve fair capacity sharing and a stable equilibrium state in a rapid fashion.

  18. Basic study on dynamic reactive-power control method with PV output prediction for solar inverter

    Directory of Open Access Journals (Sweden)

    Ryunosuke Miyoshi


    Full Text Available To effectively utilize a photovoltaic (PV system, reactive-power control methods for solar inverters have been considered. Among the various methods, the constant-voltage control outputs less reactive power compared with the other methods. We have developed a constant-voltage control to reduce the reactive-power output. However, the developed constant-voltage control still outputs unnecessary reactive power because the control parameter is constant in every waveform of the PV output. To reduce the reactive-power output, we propose a dynamic reactive-power control method with a PV output prediction. In the proposed method, the control parameter is varied according to the properties of the predicted PV waveform. In this study, we performed numerical simulations using a distribution system model, and we confirmed that the proposed method reduces the reactive-power output within the voltage constraint.

  19. Workable methods for risks control in the food chain production.

    Directory of Open Access Journals (Sweden)

    Lucilla Iacumin


    Full Text Available Several food pathologies due to new or already known micro-organisms occur all over the world every year. Food concerned are more and more frequently traditional typical, ethnical products coming from fast or slow food systems. Most of food-borne pathologies develop through neurological, gastrointestinal (watery, bloody or persistent diarrhoea abdominal pain, sickness and vomiting. The causes of these epidemics, apart from the concerned pathogen, are linked to the contaminated first matter or to contaminations occurred during food processing and consequently due to the lack of employment of the most fundamental sanitary measures and to non-control of the critical points of the HACCP (Hazard Analysis Critical Control Point systems. The pre-requirements to promote food health consist of the implementation of good agriculture husbandry and production practices, the use of HACCP systems, the training of the workers employed in the different productive rows and in the adoption of identification and traceability systems. The EU implemented the so-called hygiene pack, that is a list of rules imposing food control in each processing, marketing and consumption phase, from husbandry or cropping to consumer’s table, to promote health in food (circulating all over Europe.

  20. Research on Control Method Based on Real-Time Operational Reliability Evaluation for Space Manipulator

    Directory of Open Access Journals (Sweden)

    Yifan Wang


    Full Text Available A control method based on real-time operational reliability evaluation for space manipulator is presented for improving the success rate of a manipulator during the execution of a task. In this paper, a method for quantitative analysis of operational reliability is given when manipulator is executing a specified task; then a control model which could control the quantitative operational reliability is built. First, the control process is described by using a state space equation. Second, process parameters are estimated in real time using Bayesian method. Third, the expression of the system's real-time operational reliability is deduced based on the state space equation and process parameters which are estimated using Bayesian method. Finally, a control variable regulation strategy which considers the cost of control is given based on the Theory of Statistical Process Control. It is shown via simulations that this method effectively improves the operational reliability of space manipulator control system.

  1. The Application of Parameter Space Design Method for Generator Excitation Control (United States)

    Iki, Hiroyuki; Yoshimura, Shyuta; Uriu, Yosihisa

    Recently, control engineering changes from classical control theory to modern control theory, and analogue to digital. However, as a matter of fact, the sensitivity adjustment of the parameters using Bode diagram require many time and works. In this paper, the tool of Matlab/Simulink that adjusted the AVR control parameter of the PI control type brushless and Thyristor excitation method by using the technique for based on the parameter space planning method by QE was made. Moreover, the adjustment of the sensitivity parameter of the excitation control method intended for the dynamic stability level area in Single Machine Infinite Bus is examined with the tool.

  2. Method and apparatus for controlling LCL converters using asymmetric voltage cancellation techniques

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hunter; Sealy, Kylee Devro; Sharp, Bryan Thomas; Gilchrist, Aaron


    A method and apparatus for LCL resonant converter control utilizing Asymmetric Voltage Cancellation is described. The methods to determine the optimal trajectory of the control variables are discussed. Practical implementations of sensing load parameters are included. Simple PI, PID and fuzzy logic controllers are included with AVC for achieving good transient response characteristics with output current regulation.

  3. Trotting Gait of a Quadruped Robot Based on the Time-Pose Control Method

    Directory of Open Access Journals (Sweden)

    Cai RunBin


    Full Text Available We present the Time-Pose control method for the trotting gait of a quadruped robot on flat ground and up a slope. The method, with brief control structure, real-time operation ability and high adaptability, divides quadruped robot control into gait control and pose control. Virtual leg and intuitive controllers are introduced to simplify the model and generate the trajectory of mass centre and location of supporting legs in gait control, while redundancy optimization is used for solving the inverse kinematics in pose control. The models both on flat ground and up a slope are fully analysed, and different kinds of optimization methods are compared using the manipulability measure in order to select the best option. Simulations are performed, which prove that the Time-Pose control method is realizable for these two kinds of environment.

  4. Analysis methods for wind turbine control and electrical system dynamics (United States)

    Hinrichsen, E. N.


    The integration of new energy technologies into electric power systems requires methods which recognize the full range of dynamic events in both the new generating unit and the power system. Since new energy technologies are initially perceived as small contributors to large systems, little attention is generally paid to system integration, i.e. dynamic events in the power system are ignored. As a result, most new energy sources are only capable of base-load operation, i.e. they have no load following or cycling capability. Wind turbines are no exception. Greater awareness of this implicit (and often unnecessary) limitation is needed. Analysis methods are recommended which include very low penetration (infinite bus) as well as very high penetration (stand-alone) scenarios.

  5. Hybrid architecture active wavefront sensing and control system, and method (United States)

    Feinberg, Lee D. (Inventor); Dean, Bruce H. (Inventor); Hyde, Tristram T. (Inventor)


    According to various embodiments, provided herein is an optical system and method that can be configured to perform image analysis. The optical system can comprise a telescope assembly and one or more hybrid instruments. The one or more hybrid instruments can be configured to receive image data from the telescope assembly and perform a fine guidance operation and a wavefront sensing operation, simultaneously, on the image data received from the telescope assembly.

  6. Residual-based Methods for Controlling Discretization Error in CFD (United States)


    grid refinement factor can generally be as small r = 1.1 without round-off and iterative error polluting the results; however, from a practical...Paper 2010-4742, 40th AIAA Fluid Dynamics Conference, June 28 - July 1, 2010, Chicago, Illinois (see Shih, T.I-P...40th Fluid Dynamics Conference, 28 June - 1 July 2010, Chicago, Illinois . Zadunaisky, P.E. (1966). “A Method for the Estimation of Errors

  7. The Kinesio Taping Method for Myofascial Pain Control. (United States)

    Wu, Wei-Ting; Hong, Chang-Zern; Chou, Li-Wei


    Many people continue suffering from myofascial pain syndrome (MPS) defined as a regional pain syndrome characterized by muscle pain caused by myofascial trigger points (MTrPs) clinically. Muscle spasm and block of blood circulation can be noticed in the taut bands. In the MTrP region, nociceptors can be sensitized by the peripheral inflammatory factors and contracture of fascia can also be induced. Traditional treatments of MPS include stretching therapy, thermal treatment, electrical stimulation, massage, manipulation, trigger points injection, acupuncture, and medicine. However, the pain syndrome may not be relieved even under multiple therapies. Recently, the Kinesio Taping (KT) method is popularly used in sports injuries, postoperative complications, and various pain problems, but little research is focused on MPS with KT method. In this paper, we review the research studies on the application to KT in treating MPS and other related issues. It appears that the KT application can elevate the subcutaneous space and then increase the blood circulation and lymph fluid drainage to reduce the chemical factors around the MTrP region. Therefore, it is suggested that KT method can be used as a regular treatment or added to the previous treatment for myofascial pain.

  8. The Kinesio Taping Method for Myofascial Pain Control

    Directory of Open Access Journals (Sweden)

    Wei-Ting Wu


    Full Text Available Many people continue suffering from myofascial pain syndrome (MPS defined as a regional pain syndrome characterized by muscle pain caused by myofascial trigger points (MTrPs clinically. Muscle spasm and block of blood circulation can be noticed in the taut bands. In the MTrP region, nociceptors can be sensitized by the peripheral inflammatory factors and contracture of fascia can also be induced. Traditional treatments of MPS include stretching therapy, thermal treatment, electrical stimulation, massage, manipulation, trigger points injection, acupuncture, and medicine. However, the pain syndrome may not be relieved even under multiple therapies. Recently, the Kinesio Taping (KT method is popularly used in sports injuries, postoperative complications, and various pain problems, but little research is focused on MPS with KT method. In this paper, we review the research studies on the application to KT in treating MPS and other related issues. It appears that the KT application can elevate the subcutaneous space and then increase the blood circulation and lymph fluid drainage to reduce the chemical factors around the MTrP region. Therefore, it is suggested that KT method can be used as a regular treatment or added to the previous treatment for myofascial pain.

  9. Multi-block methods in multivariate process control

    DEFF Research Database (Denmark)

    Kohonen, J.; Reinikainen, S.P.; Aaljoki, K.


    In chemometric studies all predictor variables are usually collected in one data matrix X. This matrix is then analyzed by PLS regression or other methods. When data from several different sub-processes are collected in one matrix, there is a possibility that the effects of some sub-processes may...... vanish. If there is, for instance, mechanic data from one process and spectral data from another, the influence of the mechanic sub-process may not be detected. An application of multi-block (MB) methods, where the X-data are divided into several data blocks is presented in this study. By using MB...... methods the effect of a sub-process can be seen and an example with two blocks, near infra-red, NIR, and process data, is shown. The results show improvements in modelling task, when a MB-based approach is used. This way of working with data gives more information on the process than if all data...

  10. The Kinesio Taping Method for Myofascial Pain Control (United States)

    Wu, Wei-Ting; Hong, Chang-Zern


    Many people continue suffering from myofascial pain syndrome (MPS) defined as a regional pain syndrome characterized by muscle pain caused by myofascial trigger points (MTrPs) clinically. Muscle spasm and block of blood circulation can be noticed in the taut bands. In the MTrP region, nociceptors can be sensitized by the peripheral inflammatory factors and contracture of fascia can also be induced. Traditional treatments of MPS include stretching therapy, thermal treatment, electrical stimulation, massage, manipulation, trigger points injection, acupuncture, and medicine. However, the pain syndrome may not be relieved even under multiple therapies. Recently, the Kinesio Taping (KT) method is popularly used in sports injuries, postoperative complications, and various pain problems, but little research is focused on MPS with KT method. In this paper, we review the research studies on the application to KT in treating MPS and other related issues. It appears that the KT application can elevate the subcutaneous space and then increase the blood circulation and lymph fluid drainage to reduce the chemical factors around the MTrP region. Therefore, it is suggested that KT method can be used as a regular treatment or added to the previous treatment for myofascial pain. PMID:26185522

  11. Method for ph-controlled fermentation and biogas production

    DEFF Research Database (Denmark)


    The present invention is in the field of biomass processing and bioenergy production and facilitates efficient biomass processing and an increased production of renewable energy from processing and anaerobic fermentation of a wide variety of organic materials. In order to control the pH value of ...... of the biomass during processing thereof, a CO 2 containing gas, such as e.g. biogas or flue gas, is added to the biomass present in the buffer tank and/or in the anaerobic digester operably linked to the buffer tank...

  12. Control and Driving Methods for LED Based Intelligent Light Sources

    DEFF Research Database (Denmark)

    Beczkowski, Szymon

    such as luminous flux, efficacy and colour quality can be maximised. Simulations show that the gamut of the device can be increased, especially in the cyan colour range for \\rgb{} luminaires. A current-voltage model of light-emitting diode is presented. It utilises the fact that instantaneous values of diode......'s current and voltage correspond uniquely to a set of diode's colorimetric properties, like tristimulus values. This model can be used for colorimetric feedback in colour control loop. The model was created in thermal steady-state conditions and its validity has been tested with a diode driven with a pulsed...

  13. Plant management in natural areas: balancing chemical, mechanical, and cultural control methods (United States)

    Steven Manning; James. Miller


    After determining the best course of action for control of an invasive plant population, it is important to understand the variety of methods available to the integrated pest management professional. A variety of methods are now widely used in managing invasive plants in natural areas, including chemical, mechanical, and cultural control methods. Once the preferred...

  14. Contouring control of ball screw mechanism using a practical control method (United States)

    Hasim, Norhaslinda; Chong, Shin Horng; Keat Hee, Wai; Ibrahim, Zulkifilie


    This paper presents an improved practical controller for enhancing the contouring motion of a ball screw mechanism. Practically, a high motion control performance and ease of controller design are desired. A continuous motion nominal characteristic trajectory following (CM NCTF) control has been considered to fulfill the desired performance. The NCTF controller comprises of a nominal characteristic trajectory (NCT) and a PI compensator where the controller parameters are easily determined and it is free from exact modeling. In the present paper, the CM NCTF controller has been proposed in order to enhance the continuous motion performance such as tracking and contouring accuracies of the system. In order to justify the advantages, the CM NCTF controller was examined in tracking motion performances using an AC driven X-Y ball screw mechanism. The bandwidth of the CM NCTF controller is larger compared to the PID controller, therefore, it proved that the CM NCTF controller has fast response as compared with the PID controller. The experimental results proved that the CM NCTF controller achieves better contouring motion performances than the PID controller by showing a two times smaller motion error.

  15. Control Engineering Methods for the Design of Robust Behavioral Treatments. (United States)

    Bekiroglu, Korkut; Lagoa, Constantino; Murphy, Suzan A; Lanza, Stephanie T


    In this paper, a robust control approach is used to address the problem of adaptive behavioral treatment design. Human behavior (e.g., smoking and exercise) and reactions to treatment are complex and depend on many unmeasurable external stimuli, some of which are unknown. Thus, it is crucial to model human behavior over many subject responses. We propose a simple (low order) uncertain affine model subject to uncertainties whose response covers the most probable behavioral responses. The proposed model contains two different types of uncertainties: uncertainty of the dynamics and external perturbations that patients face in their daily life. Once the uncertain model is defined, we demonstrate how least absolute shrinkage and selection operator (lasso) can be used as an identification tool. The lasso algorithm provides a way to directly estimate a model subject to sparse perturbations. With this estimated model, a robust control algorithm is developed, where one relies on the special structure of the uncertainty to develop efficient optimization algorithms. This paper concludes by using the proposed algorithm in a numerical experiment that simulates treatment for the urge to smoke.

  16. ErrorCheck: A New Method for Controlling the Accuracy of Pose Estimates

    DEFF Research Database (Denmark)

    Holm, Preben Hagh Strunge; Petersen, Henrik Gordon


    of a validated pose refinement method. ErrorCheck uses a theoretical estimate of the pose error covariance both for validating robustness and controlling the accuracy.We illustrate the first usage of ErrorCheck by applying it to state-of-the-art methods for pose refinement and some variations of these methods......In this paper, we present ErrorCheck, which is a new method for controlling the accuracy of a computer vision based pose refinement method. ErrorCheck consists of a way for validating robustness of a pose refinement method towards false correspondences and a way of controlling the accuracy...

  17. A hierarchical voltage control method for multi-terminal AC/DC distribution system (United States)

    Ma, Zhoujun; Zhu, Hong; Zhou, Dahong; Wang, Chunning; Tang, Renquan; Xu, Honghua


    A hierarchical control system is proposed in this paper to control the voltage of multi-terminal AC/DC distribution system. The hierarchical control system consists of PCC voltage control system, DG voltage control system and voltage regulator control system. The functions of three systems are to control the voltage of DC distribution network, AC bus voltage and area voltage. A method is proposed to deal with the whole control system. And a case study indicates that when voltage fluctuating, three layers of power flow control system is running orderly, and can maintain voltage stability.

  18. A Study on Real-Time Pricing Method of Reactive Power in Voltage Profile Control Method of Future Distribution Network (United States)

    Koide, Akira; Tsuji, Takao; Oyama, Tsutomu; Hashiguchi, Takuhei; Goda, Tadahiro; Shinji, Takao; Tsujita, Shinsuke

    It is of prime importance to solve the voltage maintenance problem caused by the introduction of a large number of distributed generators. The authors have proposed “voltage profile control method” using reactive power control of distributed generators and developed new systems which can give economical incentives to DG owners who cooperate the voltage profile management in the previous works. However, it is difficult to apply the proposed economical systems to real-time operation because they are based on the optimization technology and the specific amount of incentive is informed after the control action has finished. Therefore, in this paper, we develop a new method that can determine the amount of incentives in real-time and encourage the costumers to cooperate voltage profile control method. The proposed method is tested in one feeder distribution network and its effectiveness is shown.

  19. Evaluating the Control Banding Nanotool : A qualitative risk assessment method for controlling nanoparticle exposures

    NARCIS (Netherlands)

    Zalk, D.M.; Paik, S.Y.; Swuste, P.


    Control banding (CB) strategies offer simplified processes for controlling worker exposures in the absence of firm toxicological and exposure information. The nanotechnology industry is an excellent candidate for applying such strategies with overwhelming uncertainties of work-related health risks

  20. Control capacity and a random sampling method in exploring controllability of complex networks. (United States)

    Jia, Tao; Barabási, Albert-László


    Controlling complex systems is a fundamental challenge of network science. Recent advances indicate that control over the system can be achieved through a minimum driver node set (MDS). The existence of multiple MDS's suggests that nodes do not participate in control equally, prompting us to quantify their participations. Here we introduce control capacity quantifying the likelihood that a node is a driver node. To efficiently measure this quantity, we develop a random sampling algorithm. This algorithm not only provides a statistical estimate of the control capacity, but also bridges the gap between multiple microscopic control configurations and macroscopic properties of the network under control. We demonstrate that the possibility of being a driver node decreases with a node's in-degree and is independent of its out-degree. Given the inherent multiplicity of MDS's, our findings offer tools to explore control in various complex systems.

  1. Control Method for Electromagnetic Unmanned Robot Applied to Automotive Test Based on Improved Smith Predictor Compensator

    Directory of Open Access Journals (Sweden)

    Gang Chen


    Full Text Available A new control method for an electromagnetic unmanned robot applied to automotive testing (URAT and based on improved Smith predictor compensator, and considering a time delay, is proposed. The mechanical system structure and the control system structure are presented. The electromagnetic URAT adopts pulse width modulation (PWM control, while the displacement and the current doubles as a closed-loop control strategy. The coordinated control method of multiple manipulators for the electromagnetic URAT, e.g., a skilled human driver with intelligent decision-making ability is provided, and the improved Smith predictor compensator controller for the electromagnetic URAT considering a time delay is designed. Experiments are conducted using a Ford FOCUS automobile. Comparisons between the PID control method and the proposed method are conducted. Experimental results show that the proposed method can achieve the accurate tracking of the target vehicle's speed and reduce the mileage derivation of autonomous driving, which meets the requirements of national test standards.

  2. Evolution in controls methods for the SPS power converters

    CERN Document Server

    Dinius, A H; Brazier, J C L


    In common with much accelerator specific material, there is a constant need to improve both hardware and software for power converter control. Maintenance and performance improvements of older systems have become extremely tedious and in some areas impossible. By using modern real-time software and the latest high-performance processors, such problems should be substantially reduced. This paper describes the software concepts and the hardware chosen for the upgrade of the existing facilities. Using the UNIX compatible LynxOS real time kernel, running on a PowerPC 603 in a VME environment, this new approach provides excellent performance while retaining the desired flexibility for future enhancements. The 64 channel system is implemented as a set of cooperating processes, several of which are multi-threaded. Processes include analogue function generation, analogue measurement and digital I/O, all of which are accurately scheduled by the accelerator timing system. This generalised structure, which performs comp...

  3. Advanced methods of microscope control using μManager software. (United States)

    Edelstein, Arthur D; Tsuchida, Mark A; Amodaj, Nenad; Pinkard, Henry; Vale, Ronald D; Stuurman, Nico

    μManager is an open-source, cross-platform desktop application, to control a wide variety of motorized microscopes, scientific cameras, stages, illuminators, and other microscope accessories. Since its inception in 2005, μManager has grown to support a wide range of microscopy hardware and is now used by thousands of researchers around the world. The application provides a mature graphical user interface and offers open programming interfaces to facilitate plugins and scripts. Here, we present a guide to using some of the recently added advanced μManager features, including hardware synchronization, simultaneous use of multiple cameras, projection of patterned light onto a specimen, live slide mapping, imaging with multi-well plates, particle localization and tracking, and high-speed imaging.

  4. Method and apparatus for controlling the temperature in thermoforming machines

    Energy Technology Data Exchange (ETDEWEB)

    Janke, J.


    The temperature of upper and lower parts of a forming tool making deep-drawn thermoplastic articles is controlled with a system which performs the steps of passing a coolant of predetermined total volume through the upper part and the lower part of the forming tool; measuring the temperature of the upper and lower parts; determining the actual temperature difference between the upper and lower parts; comparing the actual temperature difference with a predetermined desired temperature difference; generating a signal representing the magnitude of deviation between the actual and desired temperature differences; and, as a function of the signal, increasing the volume of coolant passing through one of the forming tool parts and decreasing the volume of coolant passing through the other of the forming tool parts for reducing the magnitude of deviation while maintaining the total volume unchanged.

  5. Diffusion in Solids Fundamentals, Methods, Materials, Diffusion-Controlled Processes

    CERN Document Server

    Mehrer, Helmut


    Diffusion is a vital topic in solid-state physics and chemistry, physical metallurgy and materials science. Diffusion processes are ubiquitous in solids at elevated temperatures. A thorough understanding of diffusion in materials is crucial for materials development and engineering. This book first gives an account of the central aspects of diffusion in solids, for which the necessary background is a course in solid state physics. It then provides easy access to important information about diffuson in metals, alloys, semiconductors, ion-conducting materials, glasses and nanomaterials. Several diffusion-controlled phenomena, including ionic conduction, grain-boundary and dislocation pipe diffusion, are considered as well. Graduate students in solid-state physics, physical metallurgy, materials science, physical and inorganic chemistry or geophysics will benefit from this book as will physicists, chemists, metallurgists, materials engineers in academic and industrial research laboratories.

  6. Advanced methods of microscope control using μManager software

    Directory of Open Access Journals (Sweden)

    Arthur D Edelstein


    Full Text Available µManager is an open-source, cross-platform desktop application, to control a wide variety of motorized microscopes, scientific cameras, stages, illuminators, and other microscope accessories. Since its inception in 2005, µManager has grown to support a wide range of microscopy hardware and is now used by thousands of researchers around the world. The application provides a mature graphical user interface and offers open programming interfaces to facilitate plugins and scripts. Here, we present a guide to using some of the recently added advanced µManager features, including hardware synchronization, simultaneous use of multiple cameras, projection of patterned light onto a specimen, live slide mapping, imaging with multi-well plates, particle localization and tracking, and high-speed imaging.

  7. Methods and systems for seed planting management and control (United States)

    Svoboda, John M.; Hess, J. Richard; Hoskinson, Reed L.; Harker, David J.


    A seed planting system providing optimal seed spacing in an agricultural field. The seed planting system includes a mobile seed planter having one or more planting shoes, or members being adapted for towing by a farm vehicle or being self-propelled. Sensors, disposed proximate to respective planting shoes, detect seed planting events and send corresponding signals to a computer. Contemporaneously, a geospatial locator acquires, and transmits to the computer, the geospatial location of each planted seed. The computer correlates the geospatial location data with the seed deposition data and generates a seed distribution profile indicating the location of each seed planted in a zone of interest to enable the control of speed spacing.

  8. Methods of making metal oxide nanostructures and methods of controlling morphology of same (United States)

    Wong, Stanislaus S; Hongjun, Zhou


    The present invention includes a method of producing a crystalline metal oxide nanostructure. The method comprises providing a metal salt solution and providing a basic solution; placing a porous membrane between the metal salt solution and the basic solution, wherein metal cations of the metal salt solution and hydroxide ions of the basic solution react, thereby producing a crystalline metal oxide nanostructure.

  9. Control Capacity and A Random Sampling Method in Exploring Controllability of Complex Networks


    Jia, Tao; Barab?si, Albert-L?szl?


    Controlling complex systems is a fundamental challenge of network science. Recent advances indicate that control over the system can be achieved through a minimum driver node set (MDS). The existence of multiple MDS's suggests that nodes do not participate in control equally, prompting us to quantify their participations. Here we introduce control capacity quantifying the likelihood that a node is a driver node. To efficiently measure this quantity, we develop a random sampling algorithm. Thi...

  10. Vibrations control of light rail transportation vehicle via PID type fuzzy controller using parameters adaptive method


    METİN, Muzaffer; GÜÇLÜ, Rahmi


    In this study, a conventional PID type fuzzy controller and parameter adaptive fuzzy controller are designed to control vibrations actively of a light rail transport vehicle which modeled as 6 degree-of-freedom system and compared performances of these two controllers. Rail vehicle model consists of a passenger seat and its suspension system, vehicle body, bogie, primary and secondary suspensions and wheels. The similarity between mathematical model and real system is shown by compar...

  11. Novel method for dynamic control of intracranial pressure. (United States)

    Luciano, Mark G; Dombrowski, Stephen M; Qvarlander, Sara; El-Khoury, Serge; Yang, Jun; Thyagaraj, Suraj; Loth, Francis


    OBJECT Intracranial pressure (ICP) pulsations are generally considered a passive result of the pulsatility of blood flow. Active experimental modification of ICP pulsations would allow investigation of potential active effects on blood and CSF flow and potentially create a new platform for the treatment of acute and chronic low blood flow states as well as a method of CSF substance clearance and delivery. This study presents a novel method and device for altering the ICP waveform via cardiac-gated volume changes. METHODS The novel device used in this experiment (named Cadence) consists of a small air-filled inelastic balloon (approximately 1.0 ml) implanted into the intracranial space and connected to an external programmable pump, triggered by an R-wave detector. Balloons were implanted into the epidural space above 1 of the hemispheres of 19 canines for up to 10 hours. When activated, the balloons were programed to cyclically inflate with the cardiac cycle with variable delay, phase, and volume. The ICP response was measured in both hemispheres. Additionally, cerebral blood flow (heat diffusion and laser Doppler) was studied in 16 canines. RESULTS This system, depending on the inflation pattern of the balloon, allowed a flattening of the ICP waveform, increase in the ICP waveform amplitude, or phase shift of the wave. This occurred with small mean ICP changes, typically around ± 2 mm Hg (15%). Bilateral ICP effects were observed with activation of the device: balloon inflation at each systole increased the systolic ICP pulse (up to 16 mm Hg, 1200%) and deflation at systole decreased or even inverted the systolic ICP pulse (-0.5 to -19 mm Hg, -5% to -1600%) in a dose-(balloon volume) dependent fashion. No aphysiological or deleterious effects on systemic pressure (≤ ±10 mm Hg; 13% change in mean pressure) or cardiac rate (≤ ± 17 beats per minute; 16% change) were observed during up to 4 hours of balloon activity. CONCLUSIONS The results of these initial

  12. A Novel Compound Control Method for Hydraulically Driven Shearer Drum Lifting

    Directory of Open Access Journals (Sweden)

    Lei Si


    Full Text Available In order to adjust shearer drum swiftly and precisely to adapt to the changes of coal seam, a compound control approach based on cerebellar model articulation control and fractional order PID controller was proposed. As the movement precision and response speed of hydraulic system were determined mainly by the control precision of valve-controlled asymmetrical hydraulic cylinder, its working principle and characteristics were analyzed in this paper, with particular focusing on the asymmetry problem. Furthermore, RBF neural network was applied to obtaining reasonable tuning parameters and a control algorithm of proposed controller was designed. Finally, laboratory experiments were developed to verify the validity and effectiveness of proposed compound control method. The testing results, compared with those for other controllers, proved that the proposed compound control method can acquire high movement precision and respond speed in the system of hydraulically driven shearer drum lifting with different control conditions.


    Directory of Open Access Journals (Sweden)

    Suo Xia Hou


    Full Text Available Nano molybdenum disulfide possesses unique chemical and physical properties. In this paper molybdenum disulfide nanoparticles with spherical and flower-like structure are prepared via a hydrothermal method. Sodium molybdate and thioacetamide are taken as precursors, polyethylene glycol (PEG-20000, hexadecyl trimethyl ammonium chloride (CTAC and anhydrous ethanol are used as additives. The properties of the product are characterized by X-ray diffraction (XRD and scanning electron microscopy (SEM. The results showed that under acidic conditions, molybdenum disulfide nanoparticles with spherical shape are obtained when PEG-20000 and CTAC are added. The nanoparticles are uniform in size with a diameter of about 100 nm. Molybdenum disulfide nanoparticles with a flower-like structure are obtained when anhydrous ethanol is added. Their diameters under sulfuric acid and hydrochloric acid conditions are 190 nm and 70 nm, respectively. Yield analysis reveals that the highest yield (which can be up to 79 % occurs by adding polyethylene glycol in a sulfuric acid environment.

  14. Tensor Product Model Transformation Based Adaptive Integral-Sliding Mode Controller: Equivalent Control Method

    Directory of Open Access Journals (Sweden)

    Guoliang Zhao


    Full Text Available This paper proposes new methodologies for the design of adaptive integral-sliding mode control. A tensor product model transformation based adaptive integral-sliding mode control law with respect to uncertainties and perturbations is studied, while upper bounds on the perturbations and uncertainties are assumed to be unknown. The advantage of proposed controllers consists in having a dynamical adaptive control gain to establish a sliding mode right at the beginning of the process. Gain dynamics ensure a reasonable adaptive gain with respect to the uncertainties. Finally, efficacy of the proposed controller is verified by simulations on an uncertain nonlinear system model.

  15. A Coefficient Diagram Method Controller with Backstepping Methodology for Robotic Manipulators (United States)

    Haouari, Fouad; Nourdine, Bali; Boucherit, Mohamed Segir; Tadjine, Mohamed


    A new robust control procedure for robot manipulators is proposed in this paper. Coefficients diagram method controllers CDM and Backstepping methodology are combined to create the novel control law. Two steps of backstepping on the resulting system are used to design a nonlinear CDM-Backstepping controller. Simulations on a PUMA robot including external disturbances, parametric uncertainties and noises are performed to show the effectiveness and feasibility of the proposed method.

  16. A new comparison of nested case-control and case-cohort designs and methods. (United States)

    Kim, Ryung S


    Existing literature comparing statistical properties of nested case-control and case-cohort methods have become insufficient for present day epidemiologists. The literature has not reconciled conflicting conclusions about the standard methods. Moreover, a comparison including newly developed methods, such as inverse probability weighting methods, is needed. Two analytical methods for nested case-control studies and six methods for case-cohort studies using proportional hazards regression model were summarized and their statistical properties were compared. The answer to which design and method is more powerful was more nuanced than what was previously reported. For both nested case-control and case-cohort designs, inverse probability weighting methods were more powerful than the standard methods. However, the difference became negligible when the proportion of failure events was very low (case-control designs coupled with the inverse probability weighting method yielded the highest statistical power among all methods for both designs. With fixed censoring times, there was little difference in efficiency between two designs when inverse probability weighting methods were used; however, the standard case-cohort methods were more powerful than the conditional logistic method for nested case-control designs. As the proportion of failure events in the full cohort became smaller (case-control methods outperformed all case-cohort methods and the choice of analytic methods within each design became less important. When the predictor of interest was binary, the standard case-cohort methods were often more powerful than the conditional logistic method for nested case-control designs.

  17. Explicit Singly Diagonally Implicit Runge-Kutta Methods and Adaptive Stepsize Control for Reservoir Simulation

    DEFF Research Database (Denmark)

    Völcker, Carsten; Jørgensen, John Bagterp; Thomsen, Per Grove


    The implicit Euler method, normally refered to as the fully implicit (FIM) method, and the implicit pressure explicit saturation (IMPES) method are the traditional choices for temporal discretization in reservoir simulation. The FIM method offers unconditionally stability in the sense of discrete......-Kutta methods, ESDIRK, Newton-Raphson, convergence control, error control, stepsize selection.......The implicit Euler method, normally refered to as the fully implicit (FIM) method, and the implicit pressure explicit saturation (IMPES) method are the traditional choices for temporal discretization in reservoir simulation. The FIM method offers unconditionally stability in the sense of discrete...... approximations, while the IMPES scheme benefits from the explicit treatment of the saturation. However, in tems of controlling the integration error, the low order of the FIM method leads to small integration steps, while the explicit treatment of the saturation may restrict the stepsizes for the IMPES scheme...

  18. Method and apparatus for laser-controlled proton beam radiology (United States)

    Johnstone, Carol J.


    A proton beam radiology system provides cancer treatment and proton radiography. The system includes an accelerator for producing an H.sup.- beam and a laser source for generating a laser beam. A photodetachment module is located proximate the periphery of the accelerator. The photodetachment module combines the H.sup.- beam and laser beam to produce a neutral beam therefrom within a subsection of the H.sup.- beam. The photodetachment module emits the neutral beam along a trajectory defined by the laser beam. The photodetachment module includes a stripping foil which forms a proton beam from the neutral beam. The proton beam is delivered to a conveyance segment which transports the proton beam to a patient treatment station. The photodetachment module further includes a laser scanner which moves the laser beam along a path transverse to the cross-section of the H.sup.- beam in order to form the neutral beam in subsections of the H.sup.- beam. As the scanning laser moves across the H.sup.- beam, it similarly varies the trajectory of the proton beam emitted from the photodetachment module and in turn varies the target location of the proton beam upon the patient. Intensity modulation of the proton beam can also be achieved by controlling the output of the laser.

  19. Continuous injection method controls down-hole corrosion. Part 1

    Energy Technology Data Exchange (ETDEWEB)

    Bradburn, J.B.; Todd, R.B.


    Recent field experience shows that a continuous down-hole injection system reduces corrosion rates up to 95% with a payout in approximately 3 months or less. The system is safe, reliable, and offers a controllable means to get inhibitor to the bottom of the well in an uncontaminated state. The system also can be used for the injection of other fluids as needed. The significance of corrosion in gas-condensate wells was first brought to the attention of the petroleum industry in 1943 by T.S. Bacon and E.A. Brown. Corrosion had been recognized as a distinct discipline since the early 1800's. Since 1943, the literature is replete with case histories, corrosion surveys, and basic and applied research data, all dealing with the corrosiveness of carbonic acid in gas wells and high-water-cut oil wells. This increased interest in corrosion and related problems focuses attention on corrosion as one of the most costly problems. Corrosion cost to the US petroleum industry was estimated in 1976, to be more than $500 million annu

  20. Bathymetry, electromagnetic streamlines and the marine controlled source electromagnetic method (United States)

    Pethick, Andrew; Harris, Brett


    Seafloor topography must influence the strength and direction of electromagnetic fields generated during deep ocean controlled source electromagnetic surveying. Neither mathematical equation nor rules of thumb provide a clear perspective of how changes in water column thickness alters electromagnetic fields that engulf hundreds of cubic kilometres of air, ocean, host and reservoir. We use streamline visualisation to provide a generalised representation of how electromagnetic fields propagate into a 2D geo-electrical setting that includes strong bathymetry. Of particular interest are: (i)' dead zones' where electric fields at the ocean floor are demonstrated to be weak and (ii) the 'airwave' that appears in the electric field streamlines as circulating vortices with a shape that is clearly influenced by changes in ocean depth. Our analysis of the distribution of electric fields for deep and shallow water examples alludes to potential benefits from placement of receivers and/or transmitters higher in the water column as is the case for towed receiver geometries. Real-time streamline representation probably holds the most value at the survey planning stage, especially for shallow water marine EM surveys where ocean bottom topography is likely to be consequential.

  1. Neurophotonics: optical methods to study and control the brain (United States)

    Doronina-Amitonova, L. V.; Fedotov, I. V.; Fedotov, A. B.; Anokhin, K. V.; Zheltikov, A. M.


    Methods of optical physics offer unique opportunities for the investigation of brain and higher nervous activity. The integration of cutting-edge laser technologies and advanced neurobiology opens a new cross-disciplinary area of natural sciences - neurophotonics - focusing on the development of a vast arsenal of tools for functional brain diagnostics, stimulation of individual neurons and neural networks, and the molecular engineering of brain cells aimed at the diagnosis and therapy of neurodegenerative and psychic diseases. Optical fibers help to confront the most challenging problems in brain research, including the analysis of molecular-cellular mechanisms of the formation of memory and behavior. New generation optical fibers provide new solutions for the development of fundamentally new, unique tools for neurophotonics and laser neuroengineering - fiber-optic neuroendoscopes and neurointerfaces. These instruments broaden research horizons when investigating the most complex brain functions, enabling a long-term multiplex detection of fluorescent protein markers, as well as photostimulation of neuronal activity in deep brain areas in living, freely moving animals with an unprecedented spatial resolution and minimal invasiveness. This emerging technology opens new horizons for understanding learning and long-term memory through experiments with living, freely moving mammals. Here, we present a brief review of this rapidly growing field of research.

  2. Low-Dispersion Fibre Bragg Gratings Written Using the Polarization Control Method

    DEFF Research Database (Denmark)

    Deyerl, Hans Jürgen; Plougmann, Nikolai; Jensen, Jesper Bo Damm


    We present two fibre Bragg gratings with reduced in-band dispersion for DWDM applications. The gratings were designed by the inverse scattering method and fabricated using the novel polarization control method for UV-writing of advanced gratings.......We present two fibre Bragg gratings with reduced in-band dispersion for DWDM applications. The gratings were designed by the inverse scattering method and fabricated using the novel polarization control method for UV-writing of advanced gratings....

  3. Magnetic agglomeration method for size control in the synthesis of magnetic nanoparticles (United States)

    Huber, Dale L [Albuquerque, NM


    A method for controlling the size of chemically synthesized magnetic nanoparticles that employs magnetic interaction between particles to control particle size and does not rely on conventional kinetic control of the reaction to control particle size. The particles are caused to reversibly agglomerate and precipitate from solution; the size at which this occurs can be well controlled to provide a very narrow particle size distribution. The size of particles is controllable by the size of the surfactant employed in the process; controlling the size of the surfactant allows magnetic control of the agglomeration and precipitation processes. Agglomeration is used to effectively stop particle growth to provide a very narrow range of particle sizes.

  4. Methods of Si based ceramic components volatilization control in a gas turbine engine (United States)

    Garcia-Crespo, Andres Jose; Delvaux, John; Dion Ouellet, Noemie


    A method of controlling volatilization of silicon based components in a gas turbine engine includes measuring, estimating and/or predicting a variable related to operation of the gas turbine engine; correlating the variable to determine an amount of silicon to control volatilization of the silicon based components in the gas turbine engine; and injecting silicon into the gas turbine engine to control volatilization of the silicon based components. A gas turbine with a compressor, combustion system, turbine section and silicon injection system may be controlled by a controller that implements the control method.

  5. High oleic sunflower biodiesel: quality control and different purification methods

    Directory of Open Access Journals (Sweden)

    Pighinelli, Anna L.M.T.


    Full Text Available The objective of the present work is to evaluate the production of biodiesel using ethanol and sunflower oil. The extraction of the sunflower oil was evaluated first. An experimental design was used to estimate the influence of the independent variables grain temperature (25º to 110ºC and expeller rotation (85 to 119rpm on the crude oil. The best result obtained was 68.38%, achieved with a rotation from 100 to 115rpm, grain temperature ranging from 25º to 30ºC and moisture content of around 7%. The next study consisted of transesterification, evaluating the influence of the ethanol, oil molar ratio and the catalyst concentration (sodium methylate on the ester-rich phase yield. The highest yield was 98.39% obtained with a molar ratio of 9:1 and 3% catalyst. An experiment was then carried out on a small reactor and the biodiesel produced was purified by three different methods: acidified water, silica and distillation. The quality aspects of the purified biodiesel samples were evaluated according to the Brazilian specifications for biodiesel, and distillation was shown to be the best method of purification.

    El objetivo del presente trabajo es evaluar la producción de biodiesel usando etanol y aceite de girasol. La extracción del aceite de girasol fue evaluada primero. Un diseño experimental fue usado para estimar la influencia de las variables independientes: temperatura del grano (25º a 110ºC y rotación del expeller (85 a 119 rpm en la obtención del aceite crudo. El mejor resultado obtenido fue un 68,38%, conseguido con una rotación de 100 a 115 rpm, una temperatura del grano de 25º a 30ºC y un contenido de humedad de alrededor del 7%. El siguiente estudio mediante transesterificación, evaluó la influencia de la relación molar etanol: aceite y concentración de catalizador (metilato sódico en el rendimiento de la fase rica en esteres. El rendimiento más alto fue 98,39% obtenido con una relación molar de 9.1 y 3% de

  6. Consumer method to control Salmonella and Listeria species in shrimp. (United States)

    Edwards, Genevieve; Janes, Marlene; Lampila, Lucina; Supan, John


    The purpose of this study was to determine whether the current consumer method of boiling shrimp until floating and pink in color is adequate for destroying Listeria and Salmonella. Shrimp samples were submerged in bacterial suspensions of Listeria and Salmonella for 30 min and allowed to air dry for 1 h under a biosafety cabinet. Color parameters were then measured with a spectrophotometer programmed with the CIELAB system. Twenty-four shrimp samples were divided into groups (days 0, 1, or 2) and stored at 4°C. The samples were treated by placing them in boiling water (100°C) on days 0, 1, and 2. The shrimp were immediately removed from the boiling water once they floated to the surface, and color parameters were measured. Bacterial counts were determined, and the log CFU per gram was calculated. The effect of sodium tripolyphosphate on the color change of cooked shrimp also was determined. Initial bacterial counts on shrimp after air drying were 5.31 ± 0.14 log CFU/g for Salmonella Enteritidis, 5.24 ± 0.31 log CFU/g for Salmonella Infantis, 5.40 ± 0.16 log CFU/g for Salmonella Typhimurium, 3.91 + 0.11 log CFU/g for Listeria innocua, 4.45 ± 0.11 log CFU/g for Listeria monocytogenes (1/2a), and 3.70 ± 0.22 log CFU/g for Listeria welshimeri. On days 0, 1, and 2, all bacterial counts were reduced to nondetectable levels for shrimp samples that floated. The average time for shrimp to float was 96 ± 8 s. The bacterial counts remained at nondetectable levels (Listeria and Salmonella contamination, but color change is not a good indication of reduction of these pathogens because of the wide natural color variation.

  7. An Adaptive Instability Suppression Controls Method for Aircraft Gas Turbine Engine Combustors (United States)

    Kopasakis, George; DeLaat, John C.; Chang, Clarence T.


    An adaptive controls method for instability suppression in gas turbine engine combustors has been developed and successfully tested with a realistic aircraft engine combustor rig. This testing was part of a program that demonstrated, for the first time, successful active combustor instability control in an aircraft gas turbine engine-like environment. The controls method is called Adaptive Sliding Phasor Averaged Control. Testing of the control method has been conducted in an experimental rig with different configurations designed to simulate combustors with instabilities of about 530 and 315 Hz. Results demonstrate the effectiveness of this method in suppressing combustor instabilities. In addition, a dramatic improvement in suppression of the instability was achieved by focusing control on the second harmonic of the instability. This is believed to be due to a phenomena discovered and reported earlier, the so called Intra-Harmonic Coupling. These results may have implications for future research in combustor instability control.

  8. A Novel Method to Balance Inverted Pendulum by Angle Sensing Using Fuzzy Logic Supervised PID Controller

    Directory of Open Access Journals (Sweden)

    Sanjeev KUMAR


    Full Text Available Inverted pendulum system is a nonlinear unstable system, an ideal experiment platform for teaching control theories and conducting various control experiments. Many abstract control concepts, such as the stability and the controllability of a control system, can all be shown visually through the inverted pendulum system. In addition to educational purposes, an inverted pendulum is also a research area for many researchers of modern control theories. Through the continuous research on new ways of controlling inverted pendulum, researchers have developed new control methods, and apply them to the high tech areas such as aeronautical engineering and robotics. Thanks to the characteristics of the system, such as high-order, instability multi-variables, non-linearity and strong coupling. This paper highlights the application and stability of inverted pendulum using fuzzy logic supervised PID controller. We are trying to propose a new method to control inverted pendulum using angle sensor.

  9. A Modified Droop Control Method for Parallel-Connected Current Source Inverters

    DEFF Research Database (Denmark)

    Wei, Baoze; Guerrero, Josep M.; Quintero, Juan Carlos Vasquez


    In this paper, a novel control method was proposed for current source inverters under the grid-connected working mode. The control scheme is based on a modified droop control method, with an additional current reference signal that will be generated instead of the voltage reference. Hence......, there is only a current control loop with droop control in the whole control scheme without voltage control loop. So it is very suitable for grid-connected current source inverter which will simplify the design of the control scheme and combine the advantage of droop control. The parallel configuration...... is widely used to acquire high power demand, but the circulating current problem is a key issue that should be considered. In this paper, a simulation based on parallel current source inverters using the proposed control scheme is provided. Simulation results showed that a good circulating current...


    Directory of Open Access Journals (Sweden)

    A. A. Margun


    Full Text Available The paper deals with the issue of control for a two-link robot manipulator under disturbances and inaccurately known parameters of the system. A method for adaptive independent control of the two-link robot manipulator based on the method of consecutive compensator is proposed. Adaptability is provided by adaptive adjustment coefficients of the consecutive compensator, and its independence consists in independent control of each link of the manipulator separately from the others. Meanwhile, non-linear effect of other links is considered as a limited external disturbance in the control channel. Dynamic equation of the manipulator was received by the Euler-Lagrange method, taking into account the effect of dynamics of manipulator engines. Since the proposed method has the simplicity of engineering implementation as compared to other adaptive methods of controlling manipulators, its usage on real objects in industry seems to be attractive. During the method simulation it was assumed that disturbances have the form of shifted harmonic signal. A series of simulations for a two-link manipulator system was conducted with the proposed controller. Simulation results confirm the effectiveness of this method in terms of external and internal disturbances. Comparison of this method with the PD controller was made. During the simulations, it was demonstrated that the proposed approach provides lower output error value than manipulator control using PD controller.

  11. Linear motion device and method for inserting and withdrawing control rods (United States)

    Smith, J.E.

    Disclosed is a linear motion device and more specifically a control rod drive mechanism (CRDM) for inserting and withdrawing control rods into a reactor core. The CRDM and method disclosed is capable of independently and sequentially positioning two sets of control rods with a single motor stator and rotor. The CRDM disclosed can control more than one control rod lead screw without incurring a substantial increase in the size of the mechanism.

  12. Current Control for Utility Interactive Inverter Using Multisampling Method Based on FPGA (United States)

    Yokoyama, Tomoki; Komiyama, Tsuyoshi; Shimada, Eigo

    In this paper, a new control method is proposed for the utility interactive inverter based on the deadbeat control with the FPGA-based hardware controller to improve the control response of an utility current. Deadbeat control is one method to ensure the output voltage or current matches with the references at the sampling instant; therefore, by adopting this control law to the utility interactive inverter, the response of the system is much improved compared with the conventional PI control. The utility interactive inverter is linked to the commercial source via the interactive inductor, and so the inverter controls the output voltage based on the deadbeat control to regulate the output current through the interactive inductor. As a result, a very fast transient response of the utility current can be achieved. The current control method using voltage deadbeat control and PLL control with quasi dq transformation with multisampling parallel processing method are implemented in the FPGA-based hardware controller for the single phase utility interactive inverter.

  13. Inspection operation aid device and method for control rod drives and hydraulic control system

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Shun-ichi; Yamamoto, Hiroki; Okuzumi, Naoaki; Ishisato, Shin-ichi


    The device of the present invention comprises an input/output device for inputting/outputting various data required for evaluation of integrity, a memorizing/storing device, an information processing device and a display device. Friction data as differential pressure signals of driving hydraulic pressures measured upon inspection/test operation of control rod drives and hydraulic pressure control system are taken into the input/output device. A result of processing for friction signal waveform pattern is calculated. The integrity and abnormality of the control rod drives and the hydraulic pressure system are evaluated using a causal relation between the result of the signal processing for obtained waveform patterns and the intelligence/knowledge of behaviors of the control rod devices and the hydraulic pressure control system thereby providing integrity data. Since the friction data can be calculated automatically by signal waveform pattern processing, there is no need to read the data manually by specialists who take part in the inspection and test. As a result, data on evaluation for integrity and abnormality of the control rod drives and the hydraulic pressure control system can be provided rapidly. (N.H.).

  14. The method to increase an adequacy and exactitude of the tracking of controlled airplane flight

    Directory of Open Access Journals (Sweden)

    В. М. Васильєв


    Full Text Available The method to increase the adequacy and exactitude of trajectory estimates for tracking of controlled flight is proposed. The method of a solution of a non-linearity problem is also offered when imitate in trajectory estimation algorithm a control signal which includes nonlinear functions of restriction. The results of computer simulation are demonstrated

  15. Haemostatic effect and tissue reactions of methods and agents used for haemorrhage control in apical surgery

    DEFF Research Database (Denmark)

    Jensen, Simon Storgaard; Yazdi, P M; Hjørting-Hansen, Erik


    To compare the haemostatic effect and tissue reactions of different agents and methods used for haemorrhage control in apical surgery.......To compare the haemostatic effect and tissue reactions of different agents and methods used for haemorrhage control in apical surgery....

  16. Vascular blood flow reconstruction from tomographic projections with the adjoint method and receding optimal control strategy (United States)

    Sixou, B.; Boissel, L.; Sigovan, M.


    In this work, we study the measurement of blood velocity with contrast enhanced computed tomography. The inverse problem is formulated as an optimal control problem with the transport equation as constraint. The velocity field is reconstructed with a receding optimal control strategy and the adjoint method. The convergence of the method is fast.

  17. A Practical Tuning Method for the Robust PID Controller with Velocity Feed-Back

    Directory of Open Access Journals (Sweden)

    Emre Sariyildiz


    Full Text Available Proportional-Integral-Derivative (PID control is the most widely used control method in industrial and academic applications due to its simplicity and efficiency. Several different control methods/algorithms have been proposed to tune the gains of PID controllers. However, the conventional tuning methods do not have sufficient performance and simplicity for practical applications, such as robotics and motion control. The performance of motion control systems may significantly deteriorate by the nonlinear plant uncertainties and unknown external disturbances, such as inertia variations, friction, external loads, etc., i.e., there may be a significant discrepancy between the simulation and experiment if the robustness is not considered in the design of PID controllers. This paper proposes a novel practical tuning method for the robust PID controller with velocity feed-back for motion control systems. The main advantages of the proposed method are the simplicity and efficiency in practical applications, i.e., a high performance robust motion control system can be easily designed by properly tuning conventional PID controllers. The validity of the proposal is verified by giving simulation and experimental results.

  18. Digitally Controlled Point of Load Converter with Very Fast Transient Response

    DEFF Research Database (Denmark)

    Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.


    three clock cycles from the time the A/D converter result is read by the control algorithm to the time the duty cycle command is updated. A typical POL converter has been built and the experimental results show that the transient response of the converter is very fast. The output voltage overshoot...... voltage mode control and very fast transient response. The DiSOM modulator is combined with a digital PID compensator algorithm is implemented in a hybrid CPLD/FPGA and is used to control a synchronous Buck converter, which is used in typical Point of Load applications. The computational time is only...

  19. The Application of PSO-AFSA Method in Parameter Optimization for Underactuated Autonomous Underwater Vehicle Control

    Directory of Open Access Journals (Sweden)

    Chunmeng Jiang


    Full Text Available In consideration of the difficulty in determining the parameters of underactuated autonomous underwater vehicles in multi-degree-of-freedom motion control, a hybrid method that combines particle swarm optimization (PSO with artificial fish school algorithm (AFSA is proposed in this paper. The optimization process of the PSO-AFSA method is firstly introduced. With the control simulation models in the horizontal plane and vertical plane, the PSO-AFSA method is elaborated when applied in control parameter optimization for an underactuated autonomous underwater vehicle. Both simulation tests and field trials were carried out to prove the efficiency of the PSO-AFSA method in underactuated autonomous underwater vehicle control parameter optimization. The optimized control parameters showed admirable control quality by enabling the underactuated autonomous underwater vehicle to reach the desired states with fast convergence.

  20. Minimum-Voltage Vector Injection Method for Sensorless Control of PMSM for Low-Speed Operations

    DEFF Research Database (Denmark)

    Xie, Ge; Lu, Kaiyuan; Kumar, Dwivedi Sanjeet


    In this paper, a simple signal injection method is proposed for sensorless control of PMSM at low speed, which ideally requires one voltage vector only for position estimation. The proposed method is easy to implement resulting in low computation burden. No filters are needed for extracting...... may also be further developed to inject two opposite voltage vectors to reduce the effects of inverter voltage error on the position estimation accuracy. The effectiveness of the proposed method is demonstrated by comparing with other sensorless control method. Theoretical analysis and experimental...... the high frequency current signals for position estimation. The use of Low-Pass Filters (LPFs) in the current control loop to filter out the fundamental current component is not necessary. Therefore, the control bandwidth of the inner current control loop may not need to be sacrificed. The proposed method...

  1. Model predictive control system and method for integrated gasification combined cycle power generation (United States)

    Kumar, Aditya; Shi, Ruijie; Kumar, Rajeeva; Dokucu, Mustafa


    Control system and method for controlling an integrated gasification combined cycle (IGCC) plant are provided. The system may include a controller coupled to a dynamic model of the plant to process a prediction of plant performance and determine a control strategy for the IGCC plant over a time horizon subject to plant constraints. The control strategy may include control functionality to meet a tracking objective and control functionality to meet an optimization objective. The control strategy may be configured to prioritize the tracking objective over the optimization objective based on a coordinate transformation, such as an orthogonal or quasi-orthogonal projection. A plurality of plant control knobs may be set in accordance with the control strategy to generate a sequence of coordinated multivariable control inputs to meet the tracking objective and the optimization objective subject to the prioritization resulting from the coordinate transformation.

  2. Performances of PID and Different Fuzzy Methods for Controlling a Ball on Beam (United States)

    Minh, Vu Trieu; Mart, Tamre; Moezzi, Reza; Oliver, Mets; Martin, Jurise; Ahti, Polder; Leo, Teder; Mart, Juurma


    This paper develops and analyses the performances evaluation of different control strategies applied for a nonlinear motion of a ball on a beam system. Comparison results provide in-depth comprehension on the stable ability of different controllers for this real mechanical application. The three different controllers are a conventional PID method, a Mamdani-type fuzzy rule method and a Sugeno-type fuzzy rule method. In this study, the PID shows the fastest sinuous reference tracking while the Mamdani-type fuzzy method proves the highest stability performance for tracking square wave motions.

  3. Analysis of Interval Control System Robust Quality Indices on the Base of Root and Coefficient Methods (United States)

    Gayvoronskiy, S. A.; Ezangina, T.; Khozhaev, I.


    Considered paper is dedicated to interval control system quality analysis with the help of root locus method and method of coefficient estimates. On the base of the first method, an algorithm of determining examinable vertices of interval characteristic polynomial coefficients polytope, which images determine robust root quality indices. On the base of coefficients method, sufficient conditions, linking coefficients of interval characteristic polynomial coefficients with quantitative estimates of robust root quality indices. With the help of both developed approaches, a robust control quality of unmanned underwater vehicle control systems was analyzed.

  4. The reconstruction of sound speed in the Marmousi model by the boundary control method

    CERN Document Server

    Ivanov, I B; Semenov, V S


    We present the results on numerical testing of the Boundary Control Method in the sound speed determination for the acoustic equation on semiplane. This method for solving multidimensional inverse problems requires no a priory information about the parameters under reconstruction. The application to the realistic Marmousi model demonstrates that the boundary control method is workable in the case of complicated and irregular field of acoustic rays. By the use of the chosen boundary controls, an `averaged' profile of the sound speed is recovered (the relative error is about $10-15\\%$). Such a profile can be further utilized as a starting approximation for high resolution iterative reconstruction methods.

  5. Observerless Scheme for Sensorless Speed Control of PMSM Using Direct Torque Control Method With LP Filter




    In this study, direct torque control (DTC) of a permanent magnet synchronous motor is realized with a sensorless speed control technique without using an observer. Space vector pulse width modulation (SVPWM) technique is applied in order to determine the switching sequence of the voltage source inverter. Torque and flux, the main variables of the DTC, are estimated by using the mathematical model of the motor. Estimated torque and flux values are compared with their references in every con...

  6. Observerless Scheme for Sensorless Speed Control of PMSM Using Direct Torque Control Method With LP Filter

    Directory of Open Access Journals (Sweden)



    Full Text Available In this study, direct torque control (DTC of a permanent magnet synchronous motor is realized with a sensorless speed control technique without using an observer. Space vector pulse width modulation (SVPWM technique is applied in order to determine the switching sequence of the voltage source inverter. Torque and flux, the main variables of the DTC, are estimated by using the mathematical model of the motor. Estimated torque and flux values are compared with their references in every control cycle. Then, according to the torque and flux demand, the voltage vector is constituted. In the proposed control scheme, speed is estimated by using flux calculations and a PI controller is used to process the torque and flux errors. Furthermore, a low-pass (LP filter is implemented within the proposed system for voltage and current harmonics suppression. The results proved that proposed scheme for the DTC provides the speed control under various torque demands without employing a sensor. The proposed system performs very well for a sensorless operation and effectively eliminates the harmonics due to the LP filter.


    Directory of Open Access Journals (Sweden)

    Seied Yasser Nikoo


    Full Text Available In this paper, a neuro-fuzzy fast terminal sliding mode control method is proposed for controlling a class of nonlinear systems with bounded uncertainties and disturbances. In this method, a nonlinear terminal sliding surface is firstly designed. Then, this sliding surface is considered as input for an adaptive neuro-fuzzy inference system which is the main controller. A proportinal-integral-derivative controller is also used to asist the neuro-fuzzy controller in order to improve the performance of the system at the begining stage of control operation. In addition, bee algorithm is used in this paper to update the weights of neuro-fuzzy system as well as the parameters of the proportinal-integral-derivative controller. The proposed control scheme is simulated for vibration control in a model of atomic force microscope system and the results are compared with conventional sliding mode controllers. The simulation results show that the chattering effect in the proposed controller is decreased in comparison with the sliding mode and the terminal sliding mode controllers. Also, the method provides the advantages of fast convergence and low model dependency compared to the conventional methods.

  8. A controller design method for 3 phase 4 wire grid connected VSI ...

    Indian Academy of Sciences (India)

    Home; Journals; Sadhana; Volume 40; Issue 5. A controller design method for 3 phase 4 wire grid connected VSI with LCL filter. Anirban Ghoshal Vinod ... Asymptotic frequency response plot and gain bandwidth requirements of the system have been used for current control and voltage controller design. A simplified lower ...

  9. Effect of weed control methods on some soil properties of a newly ...

    African Journals Online (AJOL)

    Weed control constitutes a high percentage of the total field maintenance cost of newly planted cocoa. Soil samples were collected from an experiment that was designed to evaluate some weed control methods during cocoa establishment. The objective of the experiment was to assess the effect of the weed control ...

  10. Research on Shifting Control Method of Positive Independent Mechanical Split Path Transmission for the Starting Gear

    Directory of Open Access Journals (Sweden)

    JunQiang Xi


    Full Text Available To realize a smooth and quick shift of the positive independent mechanical split path transmission (PIMSPT equipped with automatic shifting control system (ASCS, the research on the feasibility of improving shift quality by dynamic and cooperative controlling engine, steering clutches, and brakes has been conducted. The shifting control method suited to starting gear of PIMSPT has been proposed. The control method is based on control parameters, such as the driving shaft speed and its derivative. The control laws of steering clutches and brakes are presented during each gear and stage of shifting. Bench and road test results show that the proposed shifting control method can not only shorten the shift time, but also decrease the jerk of shifting effectively.



    K. A. Shcheglov; A. Y. Shcheglov


    We have researched implementation problems of control and access rights of subjects to objects in modern computer systems. We have suggested access control method based on objects access requests redirection. The method possesses a distinctive feature as compared to discretional access control. In case when a subject needs to deny writing (object modification), it is not denied but redirected (access rights are not changed, but operation is performed with another object). This gives the possi...

  12. Comparison of radiochemical purity control methods for 99Tcm radiopharmaceuticals used in hospital radiopharmacies. (United States)

    Mallol, J; Bonino, C


    The free fraction of pertechnetate in 99Tcm radiopharmaceuticals has to be tested for quality control reasons in line with the European Pharmacopoeia. Such quality control is often performed by miniaturized chromatographic methods. There are several recommended methods in the literature for quality control of the same radiopharmaceuticals, though it is unlikely that all methods are equivalent. Some of these methods were compared, taking into account different parameters (spot size, time required, analytical artifacts, true separation and shape of the chromatographic peaks, ease of handling), to verify the best method for the control of each radiopharmaceutical. It would appear that instant thin layer chromatography silica gel is the best support for these miniaturized methods, using MEK as solvent to check DTPA, DMSA, gluconate, pyrophosphate, medronate and phytate; NaCl 20% solution is the best solvent for IDA derivatives, human albumin and albumin particles (microspheres, macroaggregates).

  13. Overlay control methodology comparison: field-by-field and high-order methods (United States)

    Huang, Chun-Yen; Chiu, Chui-Fu; Wu, Wen-Bin; Shih, Chiang-Lin; Huang, Chin-Chou Kevin; Huang, Healthy; Choi, DongSub; Pierson, Bill; Robinson, John C.


    Overlay control in advanced integrated circuit (IC) manufacturing is becoming one of the leading lithographic challenges in the 3x and 2x nm process nodes. Production overlay control can no longer meet the stringent emerging requirements based on linear composite wafer and field models with sampling of 10 to 20 fields and 4 to 5 sites per field, which was the industry standard for many years. Methods that have emerged include overlay metrology in many or all fields, including the high order field model method called high order control (HOC), and field by field control (FxFc) methods also called correction per exposure. The HOC and FxFc methods were initially introduced as relatively infrequent scanner qualification activities meant to supplement linear production schemes. More recently, however, it is clear that production control is also requiring intense sampling, similar high order and FxFc methods. The added control benefits of high order and FxFc overlay methods need to be balanced with the increased metrology requirements, however, without putting material at risk. Of critical importance is the proper control of edge fields, which requires intensive sampling in order to minimize signatures. In this study we compare various methods of overlay control including the performance levels that can be achieved.

  14. Combustion Model and Control Parameter Optimization Methods for Single Cylinder Diesel Engine

    Directory of Open Access Journals (Sweden)

    Bambang Wahono


    Full Text Available This research presents a method to construct a combustion model and a method to optimize some control parameters of diesel engine in order to develop a model-based control system. The construction purpose of the model is to appropriately manage some control parameters to obtain the values of fuel consumption and emission as the engine output objectives. Stepwise method considering multicollinearity was applied to construct combustion model with the polynomial model. Using the experimental data of a single cylinder diesel engine, the model of power, BSFC, NOx, and soot on multiple injection diesel engines was built. The proposed method succesfully developed the model that describes control parameters in relation to the engine outputs. Although many control devices can be mounted to diesel engine, optimization technique is required to utilize this method in finding optimal engine operating conditions efficiently beside the existing development of individual emission control methods. Particle swarm optimization (PSO was used to calculate control parameters to optimize fuel consumption and emission based on the model. The proposed method is able to calculate control parameters efficiently to optimize evaluation item based on the model. Finally, the model which added PSO then was compiled in a microcontroller.

  15. Nonlinear fractional order proportion-integral-derivative active disturbance rejection control method design for hypersonic vehicle attitude control (United States)

    Song, Jia; Wang, Lun; Cai, Guobiao; Qi, Xiaoqiang


    Near space hypersonic vehicle model is nonlinear, multivariable and couples in the reentry process, which are challenging for the controller design. In this paper, a nonlinear fractional order proportion integral derivative (NFOPIλDμ) active disturbance rejection control (ADRC) strategy based on a natural selection particle swarm (NSPSO) algorithm is proposed for the hypersonic vehicle flight control. The NFOPIλDμ ADRC method consists of a tracking-differentiator (TD), an NFOPIλDμ controller and an extended state observer (ESO). The NFOPIλDμ controller designed by combining an FOPIλDμ method and a nonlinear states error feedback control law (NLSEF) is to overcome concussion caused by the NLSEF and conversely compensate the insufficiency for relatively simple and rough signal processing caused by the FOPIλDμ method. The TD is applied to coordinate the contradiction between rapidity and overshoot. By attributing all uncertain factors to unknown disturbances, the ESO can achieve dynamic feedback compensation for these disturbances and thus reduce their effects. Simulation results show that the NFOPIλDμ ADRC method can make the hypersonic vehicle six-degree-of-freedom nonlinear model track desired nominal signals accurately and fast, has good stability, dynamic properties and strong robustness against external environmental disturbances.

  16. Reflection Matrix Method for Controlling Light After Reflection From a Diffuse Scattering Surface (United States)





    Galagan, Roman


    Examined the methods and devices of control of porcelain insulators for presence of defects such as open microscopic porosity. It is shown that open microscopic porosity is the most dangerous defect production origin and is responsible for over 80% of failures of porcelain support insulators. Considered methods of control are divided into two groups: destructive and non-destructive. For each method are highlighted their advantages and disadvantages. The analysis showed that most of the existi...

  18. Sterility method of pest control and its potential role in an integrated sea lamprey (Petromyzon marinus) control program (United States)

    Hanson, Lee H.; Manion, Patrick J.


    The sterility method of pest control could be an effective tool in the sea lamprey (Petromyzon marinus) control program in the Great Lakes. Some of the requirements for its successful application have been met. A field study demonstrated that the release of male sea lampreys, sterilized by the injection of 100 mg/kg of P,P-bis(1-aziridinyl)-N-methylphosphinothioic amide (bisazir), will reduce the number of viable larvae produced. The actual reduction in reproductive success that occurred was directly related to the ratio of sterile to normal males in the population. The technique can be used in many ways in an integrated control program and has considerable potential for the more effective control of the sea lamprey. Eradication is a distinct possibility.Key words: sea lamprey, Petromyzon marinus; pest control, fish control, sterile-male technique, sterilization, chemosterilants, bisazir, Great Lakes

  19. Self Tuning Techniques on PLC Background and Control Systems With Self Tuning Methods Design

    Directory of Open Access Journals (Sweden)

    Jiri Koziorek


    Full Text Available Advanced Process Control techniques have become standard functions of distributed control systems. Self tuning methods belong to Advanced Process Control (APC techniques. APC techniques contain software packages for advanced control based on mathematical methods. APC tools are designed to increase the process capacity, yield and quality of products. Most of nowadays digital industry regulators and PLCs are provided with some kind of the self tuning constant algorithm. Practical part of the paper deals with design of the control systems which contain self tuning regulator. A control system with PID Self Tuner by Siemens and with visualization in WinCC is designed. There is a description of an implementation of the PID regulator as a function block which can be also used for extension control functions. Control systems for relay and moment self tuner with visualizations in WinCC are also designed.

  20. A new computer method for temperature measurement based on an optimal control problem

    NARCIS (Netherlands)

    Damean, N.; Houkes, Z.; Regtien, Paulus P.L.


    A new computer method to measure extreme temperatures is presented. The method reduces the measurement of the unknown temperature to the solving of an optimal control problem, using a numerical computer. Based on this method, a new device for temperature measurement is built. It consists of a

  1. A Primal-Dual Augmented Lagrangian Method for Optimal Control of ...

    African Journals Online (AJOL)

    Moreover, the formulation of a penalized matrix in the primal-dual variables with mesh-refinement strategy guarantees the reliability of the algorithm. Numerical experiments verify the efficiency of the proposed method. Keywords: Optimal control,primal-dual methods, augmented Lagrangian methods, conjugate gradient ...

  2. On Advanced Control Methods toward Power Capture and Load Mitigation in Wind Turbines

    Directory of Open Access Journals (Sweden)

    Yuan Yuan


    Full Text Available This article provides a survey of recently emerged methods for wind turbine control. Multivariate control approaches to the optimization of power capture and the reduction of loads in components under time-varying turbulent wind fields have been under extensive investigation in recent years. We divide the related research activities into three categories: modeling and dynamics of wind turbines, active control of wind turbines, and passive control of wind turbines. Regarding turbine dynamics, we discuss the physical fundamentals and present the aeroelastic analysis tools. Regarding active control, we review pitch control, torque control, and yaw control strategies encompassing mathematical formulations as well as their applications toward different objectives. Our survey mostly focuses on blade pitch control, which is considered one of the key elements in facilitating load reduction while maintaining power capture performance. Regarding passive control, we review techniques such as tuned mass dampers, smart rotors, and microtabs. Possible future directions are suggested.

  3. Applications of a Controller Design Method for Nonholonomic Systems to Auto-Steering Vehicles (United States)

    Hamamatsu, Masanori; Kubota, Tetsuya; Kohno, Yukinobu; Iwata, Shinichi

    In the industrial field of motion control, many systems are nonholonomic, and thefore are difficult to control by static state feedback. As a controller design method for nonholonomic systems, a time-state control form that is applicable to a broad class of nonholonomic systems has been proposed. This paper describes three applications of controllers designed to utilize the time-state control form for the motion control of the following ground vehicles: a large-scale transfer crane, a rotary snow remover, and the mobile field of the Sapporo Dome stadium. In the first two examples, we develop a control function in a time-state control form into an integral type, and a combination of a filter and the Smith compensator. In the third example, we confirm the validity of the motion control by computer simulations and actual experiments.

  4. On Advanced Control Methods toward Power Capture and Load Mitigation in Wind Turbines


    Yuan Yuan; Jiong Tang


    This article provides a survey of recently emerged methods for wind turbine control. Multivariate control approaches to the optimization of power capture and the reduction of loads in components under time-varying turbulent wind fields have been under extensive investigation in recent years. We divide the related research activities into three categories: modeling and dynamics of wind turbines, active control of wind turbines, and passive control of wind turbines. Regarding turbine dynamics, ...

  5. Modelling and control for laser based welding processes: modern methods of process control to improve quality of laser-based joining methods (United States)

    Zäh, Ralf-Kilian; Mosbach, Benedikt; Hollwich, Jan; Faupel, Benedikt


    To ensure the competitiveness of manufacturing companies it is indispensable to optimize their manufacturing processes. Slight variations of process parameters and machine settings have only marginally effects on the product quality. Therefore, the largest possible editing window is required. Such parameters are, for example, the movement of the laser beam across the component for the laser keyhole welding. That`s why it is necessary to keep the formation of welding seams within specified limits. Therefore, the quality of laser welding processes is ensured, by using post-process methods, like ultrasonic inspection, or special in-process methods. These in-process systems only achieve a simple evaluation which shows whether the weld seam is acceptable or not. Furthermore, in-process systems use no feedback for changing the control variables such as speed of the laser or adjustment of laser power. In this paper the research group presents current results of the research field of Online Monitoring, Online Controlling and Model predictive controlling in laser welding processes to increase the product quality. To record the characteristics of the welding process, tested online methods are used during the process. Based on the measurement data, a state space model is ascertained, which includes all the control variables of the system. Depending on simulation tools the model predictive controller (MPC) is designed for the model and integrated into an NI-Real-Time-System.

  6. Mixing Methods in Randomized Controlled Trials (RCTs): Validation, Contextualization, Triangulation, and Control (United States)

    Spillane, James P.; Pareja, Amber Stitziel; Dorner, Lisa; Barnes, Carol; May, Henry; Huff, Jason; Camburn, Eric


    In this paper we described how we mixed research approaches in a Randomized Control Trial (RCT) of a school principal professional development program. Using examples from our study we illustrate how combining qualitative and quantitative data can address some key challenges from validating instruments and measures of mediator variables to…

  7. An Improved Distributed Secondary Control Method for DC Microgrids With Enhanced Dynamic Current Sharing Performance

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Panbao; Lu, Xiaonan; Yang, Xu; Wang, Wei; Xu, Dianguo


    This paper proposes an improved distributed secondary control scheme for dc microgrids (MGs), aiming at overcoming the drawbacks of conventional droop control method. The proposed secondary control scheme can remove the dc voltage deviation and improve the current sharing accuracy by using voltage-shifting and slope-adjusting approaches simultaneously. Meanwhile, the average value of droop coefficients is calculated, and then it is controlled by an additional controller included in the distributed secondary control layer to ensure that each droop coefficient converges at a reasonable value. Hence, by adjusting the droop coefficient, each participating converter has equal output impedance, and the accurate proportional load current sharing can be achieved with different line resistances. Furthermore, the current sharing performance in steady and transient states can be enhanced by using the proposed method. The effectiveness of the proposed method is verified by detailed experimental tests based on a 3 × 1 kW prototype with three interface converters.

  8. A Quality Control Method Based on an Improved Random Forest Algorithm for Surface Air Temperature Observations

    Directory of Open Access Journals (Sweden)

    Xiaoling Ye


    Full Text Available A spatial quality control method, ARF, is proposed. The ARF method incorporates the optimization ability of the artificial fish swarm algorithm and the random forest regression function to provide quality control for multiple surface air temperature stations. Surface air temperature observations were recorded at stations in mountainous and plain regions and at neighboring stations to test the performance of the method. Observations from 2005 to 2013 were used as a training set, and observations from 2014 were used as a testing set. The results indicate that the ARF method is able to identify inaccurate observations; and it has a higher rate of detection, lower rate of change for the quality control parameters, and fewer type I errors than traditional methods. Notably, the ARF method yielded low performance indexes in areas with complex terrain, where traditional methods were considerably less effective. In addition, for stations near the ocean without sufficient neighboring stations, different neighboring stations were used to test the different methods. Whereas the traditional methods were affected by station distribution, the ARF method exhibited fewer errors and higher stability. Thus, the method is able to effectively reduce the effects of geographical factors on spatial quality control.

  9. A Current Sensorless MPPT Control Method for a Stand-Alone-Type PV Generation System (United States)

    Itako, Kazutaka; Mori, Takeaki

    In this paper, a current sensorless MPPT control method for a stand-alone-type PV generation system is proposed. This control method offers advantages of the simplified hardware configuration and the low cost, by using only one sensor to measure the PV output voltage. In the application to stand-alone-type with a battery load, the experimental results show that the estimated values of PV output current are accurate, and the use of the proposed MPPT control increases the PV generated energy by 16.3% compared to the conventional system. Furthermore, it is clarified that the proposed method has extremely high UUF (Useful utilization factor) of 98.7%.

  10. Networked and Distributed Control Method with Optimal Power Dispatch for Islanded Microgrids

    DEFF Research Database (Denmark)

    Li, Qiang; Peng, Congbo; Chen, Minyou


    of controllable agents. The distributed control laws derived from the first subgraph guarantee the supply-demand balance, while further control laws from the second subgraph reassign the outputs of controllable distributed generators, which ensure active and reactive power are dispatched optimally. However...... according to our proposition. Finally, the method is evaluated over seven cases via simulation. The results show that the system performs as desired, even if environmental conditions and load demand fluctuate significantly. In summary, the method can rapidly respond to fluctuations resulting in optimal...

  11. Utilization of Advanced Methods in the Control of a Mechatronic System with Flexible Elements

    Directory of Open Access Journals (Sweden)

    Juhás Martin


    Full Text Available Analysis of the negative impact of a mechatronic system with the flexible elements parameter error and the possibilities of impact reduction are presented in this contribution. Two advanced methods – the Model Predictive Control method and the inclusion of an LMS filter into the control process are proposed for the reduction of the insufficient effect of a double notch filter, which was initially integrated into the system for elimination of two-mass flexible joint parasitic frequencies. Simulation experiments results – response of system angular velocity and control process quality analysis confirmed the correctness of the proposition for the usage of these progressive control elements.

  12. Method study on fuzzy-PID adaptive control of electric-hydraulic hitch system (United States)

    Li, Mingsheng; Wang, Liubu; Liu, Jian; Ye, Jin


    In this paper, fuzzy-PID adaptive control method is applied to the control of tractor electric-hydraulic hitch system. According to the characteristics of the system, a fuzzy-PID adaptive controller is designed and the electric-hydraulic hitch system model is established. Traction control and position control performance simulation are carried out with the common PID control method. A field test rig was set up to test the electric-hydraulic hitch system. The test results showed that, after the fuzzy-PID adaptive control is adopted, when the tillage depth steps from 0.1m to 0.3m, the system transition process time is 4s, without overshoot, and when the tractive force steps from 3000N to 7000N, the system transition process time is 5s, the system overshoot is 25%.

  13. A yaw-moment control method based on a vehicle's lateral jerk information (United States)

    Yamakado, Makoto; Nagatsuka, Keiichiro; Takahashi, Junya


    Previously, a new control concept called 'G-vectoring control (GVC)' to improve vehicle agility and stability was developed. GVC is an automatic longitudinal acceleration control method that responds to vehicle lateral jerk caused by the driver's steering manoeuvres. In this paper, a new yaw-moment control method, which generates a stabilising moment during the GVC command and has positive acceleration value and the driver's accelerator pedal input is zero, was proposed. A new hybrid control, which comprises GVC, electric stability control and this new control, was constructed, and it was installed in a test vehicle and tested on a snowy surface. The very high potential for improvement in both agility and stability was confirmed.

  14. Method and system for redundancy management of distributed and recoverable digital control system (United States)

    Stange, Kent (Inventor); Hess, Richard (Inventor); Kelley, Gerald B (Inventor); Rogers, Randy (Inventor)


    A method and system for redundancy management is provided for a distributed and recoverable digital control system. The method uses unique redundancy management techniques to achieve recovery and restoration of redundant elements to full operation in an asynchronous environment. The system includes a first computing unit comprising a pair of redundant computational lanes for generating redundant control commands. One or more internal monitors detect data errors in the control commands, and provide a recovery trigger to the first computing unit. A second redundant computing unit provides the same features as the first computing unit. A first actuator control unit is configured to provide blending and monitoring of the control commands from the first and second computing units, and to provide a recovery trigger to each of the first and second computing units. A second actuator control unit provides the same features as the first actuator control unit.

  15. Hierarchical Robot Control System and Method for Controlling Select Degrees of Freedom of an Object Using Multiple Manipulators (United States)

    Abdallah, Muhammad E. (Inventor); Platt, Robert (Inventor); Wampler, II, Charles W. (Inventor)


    A robotic system includes a robot having manipulators for grasping an object using one of a plurality of grasp types during a primary task, and a controller. The controller controls the manipulators during the primary task using a multiple-task control hierarchy, and automatically parameterizes the internal forces of the system for each grasp type in response to an input signal. The primary task is defined at an object-level of control, e.g., using a closed-chain transformation, such that only select degrees of freedom are commanded for the object. A control system for the robotic system has a host machine and algorithm for controlling the manipulators using the above hierarchy. A method for controlling the system includes receiving and processing the input signal using the host machine, including defining the primary task at the object-level of control, e.g., using a closed-chain definition, and parameterizing the internal forces for each of grasp type.

  16. Control of a Linear Distillation Column Using Type-2 Fuzzy Method Optimized by Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Abbas Asgari


    Full Text Available The distillation process is important process in the chemical industry and has wide application in industry. Distillation tower is used by chemical engineers as a popular tool to separate materials and is the most common method for separating materials. Keeping constant the product composition in the distillation column is very important from control perspective. Control of these complicated processes need intelligent methods to adopt the appropriate decision for control based on the behavior of the system. Between intelligent methods, fuzzy technique has superior response in complex systems control and so is used in this study. In this article at first, a type-1fuzzy controller is designed for linear model of distillation tower. In design of this Fuzzy controller, genetic algorithm (GA is used for optimization of fuzzy rules base. It has been shown that the fuzzy controller is better than conventional PI one. Then the type-1 fuzzy controller has been replaced with type-2 fuzzy controller and has been shown that the performance of type-2 is better than type-1 in various points of view. In this study, the MATLAB/SIMULINK software has been used for modeling and implementing the proposed methods.

  17. Improving disturbance rejection of PID controllers by means of the magnitude optimum method. (United States)

    Vrancić, Damir; Strmcnik, Stanko; Kocijan, Jus; de Moura Oliveira, P B


    The magnitude optimum (MO) method provides a relatively fast and non-oscillatory closed-loop tracking response for a large class of process models frequently encountered in the process and chemical industries. However, the deficiency of the method is poor disturbance rejection performance of some processes. In this paper, disturbance rejection performance of the PID controller is improved by applying the "disturbance rejection magnitude optimum" (DRMO) optimisation method, while the tracking performance has been improved by a set-point weighting and set-point filtering PID controller structure. The DRMO tuning method requires numerical optimisation for the calculation of PID controller parameters. The method was applied to two different 2-degrees-of-freedom PID controllers and has been tested on several different representatives of process models and one laboratory set-up. A comparison with some other tuning methods has shown that the proposed tuning method, with a set-point filtering PID controller, is quite efficient in improving disturbance rejection performance, while retaining tracking performance comparable with the original MO method. 2009 ISA. Published by Elsevier Ltd. All rights reserved.

  18. The development of Inverter Fuzzy Logic Control for Induction Motor Control by Vector Control Method in Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Era Purwanto


    Full Text Available In response to concerns about energy cost, energy dependence, and environmental damage, a rekindling of interest in electric vehicles (EV’s has been obvious. Thus, the development of power electronics technology for EV’s will take an accelerated pace to fulfill the market needs, regarding with the problem in this paper is presented development of fuzzy logic inverter in induction motor control for electric vehicle propulsion. The Fuzzy logic inverter is developed in this system to directed toward developing an improved propulsion system for electric vehicles applications, the fuzzy logic controller is used for switching process. This paper is describes the design concepts, configuration, controller for inverter fuzzy logic and drive system is developed for this high-performance electric vehicle.

  19. A multi-factor designation method for mapping particulate-pollution control zones in China. (United States)

    Qin, Y; Xie, S D


    A multi-factor designation method for mapping particulate-pollution control zones was brought out through synthetically considering PM(10) pollution status, PM(10) anthropogenic emissions, fine particle pollution, long-range transport and economic situation. According to this method, China was divided into four different particulate-pollution control regions: PM Suspended Control Region, PM(10) Pollution Control Region, PM(2.5) Pollution Control Region and PM(10) and PM(2.5) Common Control Region, which accounted for 69.55%, 9.66%, 4.67% and 16.13% of China's territory, respectively. The PM(10) and PM(2.5) Common Control Region was mainly distributed in Bohai Region, Yangtze River Delta, Pearl River Delta, eastern of Sichuan province and Chongqing municipality, calling for immediate control of both PM(10) and PM(2.5). Cost-effective control effects can be achieved through concentrating efforts on PM(10) and PM(2.5) Common Control Region to address 60.32% of national PM(10) anthropogenic emissions. Air quality in districts belonging to PM(2.5) Pollution Control Region suggested that Chinese national ambient air quality standard for PM(10) was not strict enough. The result derived from application to China proved that this approach was feasible for mapping pollution control regions for a country with vast territory, complicated pollution characteristics and limited available monitoring data. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. New Active Control Method Based on Using Multiactuators and Sensors Considering Uncertainty of Parameters

    Directory of Open Access Journals (Sweden)

    Babak Karimpour


    Full Text Available New approach is presented for controlling the structural vibrations. The proposed active control method is based on structural dynamics theories in which multiactuators and sensors are utilized. Each actuator force is modeled as an equivalent viscous damper so that several lower vibration modes are damped critically. This subject is achieved by simple mathematical formulation. The proposed method does not depend on the type of dynamic load and it could be applied to control structures with multidegrees of freedom. For numerical verification of proposed method, several criterions such as maximum displacement, maximum kinetic energy, maximum drift, and time history of controlled force and displacement are evaluated in two- , five- , and seven-story shear buildings, subjected to the harmonic load, impact force, and the Elcentro base excitation. This study shows that the proposed method has suitable efficiency for reducing structural vibrations. Moreover, the uncertainty effect of different parameters is investigated here.

  1. The impact of parameter identification methods on drug therapy control in an intensive care unit

    National Research Council Canada - National Science Library

    Hann, CE; Chase, JG; Ypma, MF; Elfring, J Jos; Nor, NHM; Lawrence, P; Shaw, GM


    This paper investigates the impact of fast parameter identification methods, which do not require any forward simulations, on model-based glucose control, using retrospective data in the Christchurch...


    This presentation describes the preliminary results of the evaluations of the alternative asbestos control method for demolishing buildings containing asbestos, and are covered under the regulatory requirements of the Asbestos NESHAP. This abstract and presentation are based, at ...

  3. Decoupling Control for Dual-Winding Bearingless Switched Reluctance Motor Based on Improved Inverse System Method

    Directory of Open Access Journals (Sweden)

    Zhiying Zhu


    Full Text Available Dual-winding bearingless switched reluctance motor (BSRM is a multivariable high-nonlinear system characterized by strong coupling, and it is not completely reversible. In this paper, a new decoupling control strategy based on improved inverse system method is proposed. Robust servo regulator is adopted for the decoupled plants to guarantee control performances and robustness. A phase dynamic compensation filter is also designed to improve system stability at high-speed. In order to explain the advantages of the proposed method, traditional methods are compared. The tracking and decoupling characteristics as well as disturbance rejection and robustness are deeply analyzed. Simulation and experiments results show that the decoupling control of dual-winding BSRM in both reversible and irreversible domains can be successfully resolved with the improved inverse system method. The stability and robustness problems induced by inverse controller can be effectively solved by introducing robust servo regulator and dynamic compensation filter.


    Directory of Open Access Journals (Sweden)

    V. M. Karpenko


    Full Text Available In the article the original author's tractability of the methods of continuous automatic control of flow characteristics of sand blends with the use of imitation models received on the original experimental system is offered.

  5. Decentralised control method for DC microgrids with improved current sharing accuracy

    DEFF Research Database (Denmark)

    Yang, Jie; Jin, Xinmin; Wu, Xuezhi


    A decentralised control method that deals with current sharing issues in dc microgrids (MGs) is proposed in this study. The proposed method is formulated in terms of ‘modified global indicator’ concept, which was originally proposed to improve reactive power sharing in ac MGs. In this work......, the ‘modified global indicator’ concept is extended to coordinate dc MGs, which aims to preserve the main features offered by decentralised control methods such as no need of communication links, central controller or knowledge of the microgrid topology and parameters. This global indicator is inserted between...... a shunt virtual resistance. The operation under multiple dc-buses is also included in order to enhance the applicability of the proposed controller. A detailed mathematical model including the effect of network mismatches is derived for analysis of the stability of the proposed controller. The feasibility...

  6. On the Effect of Combination of Statistical and Judgemental Stock Control Methods

    Directory of Open Access Journals (Sweden)

    Inna Kholidasari


    Full Text Available Stock control is the most important aspect in an inventory system. It determines the safety stock in order to ensure that products are readily available when the customers require them. The decision makers in organizations tend to rely on software solution in obtaining stock control solutions since they have to manage a massive number of Stock Keeping Units (SKUs. However, managers intervene in the system and use their judgement to adjust or decide on various quantitative elements. This research discusses the effects of combination of stock control methods. An extended database of approximately 1,800 SKUs from an electronics company is analyzed. Then, a simulation experiment is performed in order to evaluate in a dynamic fashion what are the effects of applying combined stock control methods. The findings indicate that the combined method of stock control seems to improve the performance of the inventory system, especially in reducing inventory investment.

  7. Yaw controller design of stratospheric airship based on phase plane method

    Directory of Open Access Journals (Sweden)

    Miao Jinggang


    Full Text Available Recently, stratospheric airships prefer to employ a vectored tail rotor or differential main propellers for the yaw control, rather than the control surfaces like common low-altitude airship. The load capacity of vectored mechanism and propellers are always limited by the weight and strength, which bring challenges for the attitude controller. In this paper, the yaw channel of airship dynamics is firstly rewritten as a simplified two-order dynamics equation and the dynamic characteristics is analyzed with a phase plane method. Analysis shows that when ignoring damping, the yaw control channel is available to the minimum principle of Pontryagin for optimal control, which can obtain a Bang–Bang controller. But under this controller, the control output could be bouncing around the theoretical switch curve due to the presence of disturbance and damping, which makes adverse effects for the servo structure. Considering the structure requirements of actuators, a phase plane method controller is employed, with a dead zone surrounded by several phase switch curve. Thus, the controller outputs are limited to finite values. Finally, through the numerical simulation and actual flight experiment, the method is proved to be effective.

  8. A Sliding Mode Control of Semi-Active Suspension Systems with Describing Function Method (United States)

    Toyama, Shigehiro; Ikeda, Fujio

    This paper presents a sliding mode controller of semi-active suspension systems. The sliding mode controller is designed by the describing function method so that a switching function is enforced into a desired limit cycle instead of a perfect sliding mode. Although the proposed sliding mode controller cannot generate the limit cycle as desired because of the passive constraint of controllable dampers, restricting the switching function in the vicinity of the origin can suppress the deterioration due to the passive constraint, such as increase of jerk of the sprung mass. Finally, simulation results show the effectiveness of the proposed controller.

  9. Non- chemical methods of seed treatment for control of seed- borne pathogens on vegetables


    Amein, T.; Wright, S. A. I.; Wikström, M; Schmitt, A.; Koch, E.; Wolf, J.; de Groot, S.; Forsberg, G.; Werner, S; Jahn, M


    Abstract – The aim of EU-project "Seed Treatments for Organic Vegetable Production" (STOVE) was to evaluate non-chemical methods for control of seed-borne pathogens in organic vegetable production. Physical (hot air, hot water and electron) and biologi-cal (microorganisms and different agents of natural origin) methods have been investigated. Trials have been carried out with different patho-systems such as cabbage / Alternaria spp and parsley / Septoria pet-roselini. Good control was genera...

  10. A simple method for the quality control of [F-18]FDG

    DEFF Research Database (Denmark)

    Koziorowski, J.


    Most automated synthesis modules produce [F-18]FDG within half an hour, but the quality control involving up to three separate methods and three different analytical systems is time consuming. The use of HPLC, TLC, and GC for the quality control of [F-18]FDG is both time consuming and expensive...... (high purchase costs). Presented here is a method using a single HPLC system for all three analyses. (C) 2010 Elsevier Ltd. All rights reserved...

  11. A simple method for the quality control of [{sup 18}F]FDG

    Energy Technology Data Exchange (ETDEWEB)

    Koziorowski, J., E-mail: jacek@heh.regionh.d [Herlev Hospital, Copenhagen University, Dept. Clin. Phys. Nucl. Med., 54P1, Herlev Ringvej 75, DK-2730 Herlev (Denmark)


    Most automated synthesis modules produce [{sup 18}F]FDG within half an hour, but the quality control involving up to three separate methods and three different analytical systems is time consuming. The use of HPLC, TLC, and GC for the quality control of [{sup 18}F]FDG is both time consuming and expensive (high purchase costs). Presented here is a method using a single HPLC system for all three analyses.

  12. SCHEME (Soft Control Human error Evaluation MEthod) for advanced MCR HRA

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Inseok; Jung, Wondea [KAERI, Daejeon (Korea, Republic of); Seong, Poong Hyun [KAIST, Daejeon (Korea, Republic of)


    The Technique for Human Error Rate Prediction (THERP), Korean Human Reliability Analysis (K-HRA), Human Error Assessment and Reduction Technique (HEART), A Technique for Human Event Analysis (ATHEANA), Cognitive Reliability and Error Analysis Method (CREAM), and Simplified Plant Analysis Risk Human Reliability Assessment (SPAR-H) in relation to NPP maintenance and operation. Most of these methods were developed considering the conventional type of Main Control Rooms (MCRs). They are still used for HRA in advanced MCRs even though the operating environment of advanced MCRs in NPPs has been considerably changed by the adoption of new human-system interfaces such as computer-based soft controls. Among the many features in advanced MCRs, soft controls are an important feature because the operation action in NPP advanced MCRs is performed by soft controls. Consequently, those conventional methods may not sufficiently consider the features of soft control execution human errors. To this end, a new framework of a HRA method for evaluating soft control execution human error is suggested by performing the soft control task analysis and the literature reviews regarding widely accepted human error taxonomies. In this study, the framework of a HRA method for evaluating soft control execution human error in advanced MCRs is developed. First, the factors which HRA method in advanced MCRs should encompass are derived based on the literature review, and soft control task analysis. Based on the derived factors, execution HRA framework in advanced MCRs is developed mainly focusing on the features of soft control. Moreover, since most current HRA database deal with operation in conventional type of MCRs and are not explicitly designed to deal with digital HSI, HRA database are developed under lab scale simulation.

  13. A High-Performance Control Method of Constant V/f-Controlled Induction Motor Drives for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Long Chen


    Full Text Available A three-phase induction motor used as a propulsion system for the electric vehicle (EV is a nonlinear, multi-input multi-output, and strong coupling system. For such a complicated model system with unmeasured and unavoidable disturbances, as well as parameter variations, the conventional vector control method cannot meet the demands of high-performance control. Therefore, a novel control strategy named least squares support vector machines (LSSVM inverse control is presented in the paper. Invertibility of the induction motor in the constant V/f control mode is proved to confirm its feasibility. The LSSVM inverse is composed of an LSSVM approximating the nonlinear mapping of the induction motor and two integrators. The inverse model of the constant V/f-controlled induction motor drive is obtained by using LSSVM, and then the optimal parameters of LSSVM are determined automatically by applying a modified particle swarm optimization (MPSO. Cascading the LSSVM inverse with the induction motor drive system, the pseudolinear system can be obtained. Thus, it is easy to design the closed-loop linear regulator. The simulation results verify the effectiveness of the proposed method.

  14. Method for simulating predictive control of building systems operation in the early stages of building design

    DEFF Research Database (Denmark)

    Petersen, Steffen; Svendsen, Svend


    A method for simulating predictive control of building systems operation in the early stages of building design is presented. The method uses building simulation based on weather forecasts to predict whether there is a future heating or cooling requirement. This information enables the thermal...... control systems of the building to respond proactively to keep the operational temperature within the thermal comfort range with the minimum use of energy. The method is implemented in an existing building simulation tool designed to inform decisions in the early stages of building design through...... parametric analysis. This enables building designers to predict the performance of the method and include it as a part of the solution space. The method furthermore facilitates the task of configuring appropriate building systems control schemes in the tool, and it eliminates time consuming manual...

  15. Application of sliding mode methods to the design of reconfigurable flight control systems (United States)

    Wells, Scott Russell

    Observer-based sliding mode control is investigated for application to aircraft reconfigurable flight control. A comprehensive overview of reconfigurable flight control is given, including a review of the current state-of-the-art within the subdisciplines of fault detection, parameter identification, adaptive control schemes, and dynamic control allocation. Of the adaptive control methods reviewed, sliding mode control (SMC) appears very promising due its property of invariance to matched uncertainty. An overview of sliding mode control is given and its remarkable properties are demonstrated by example. Sliding mode methods, however, are difficult to implement because unmodeled parasitic dynamics cause immediate and severe instability. This presents a challenge for all practical applications with limited bandwidth actuators. One method to deal with parasitic dynamics is the use of an asymptotic observer in the feedback path. Observer-based SMC is investigated, and a method for selecting observer gains is offered. An additional method for shaping the feedback loop using a filter is also developed. It is shown that this SMC prefilter is equivalent to a form of model reference hedging. A complete design procedure is given which takes advantage of the sliding mode boundary layer to recast the SMC as a linear control law. Frequency domain loop shaping is then used to design the sliding manifold. Finally, three aircraft applications are demonstrated. An F-18/HARV is used to demonstrate a SISO pitch rate tracking controller. It is also used to demonstrate a MIMO lateral-directional roll rate tracking controller. The last application is a full linear six degree-of-freedom advanced tailless fighter model. The observer-based SMC is seen to provide excellent tracking with superior robustness to parameter changes and actuator failures.

  16. Industrial Process Identification and Control Design Step-test and Relay-experiment-based Methods

    CERN Document Server

    Liu, Tao


      Industrial Process Identification and Control Design is devoted to advanced identification and control methods for the operation of continuous-time processes both with and without time delay, in industrial and chemical engineering practice.   The simple and practical step- or relay-feedback test is employed when applying the proposed identification techniques, which are classified in terms of common industrial process type: open-loop stable; integrating; and unstable, respectively. Correspondingly, control system design and tuning models that follow are presented for single-input-single-output processes.   Furthermore, new two-degree-of-freedom control strategies and cascade control system design methods are explored with reference to independently-improving, set-point tracking and load disturbance rejection. Decoupling, multi-loop, and decentralized control techniques for the operation of multiple-input-multiple-output processes are also detailed. Perfect tracking of a desire output trajectory is realiz...

  17. Numerical Methods for Solution of the Extended Linear Quadratic Control Problem

    DEFF Research Database (Denmark)

    Jørgensen, John Bagterp; Frison, Gianluca; Gade-Nielsen, Nicolai Fog


    In this paper we present the extended linear quadratic control problem, its efficient solution, and a discussion of how it arises in the numerical solution of nonlinear model predictive control problems. The extended linear quadratic control problem is the optimal control problem corresponding...... to the Karush-Kuhn-Tucker system that constitute the majority of computational work in constrained nonlinear and linear model predictive control problems solved by efficient MPC-tailored interior-point and active-set algorithms. We state various methods of solving the extended linear quadratic control problem...... and discuss instances in which it arises. The methods discussed in the paper have been implemented in efficient C code for both CPUs and GPUs for a number of test examples....

  18. Genetic association tests: a method for the joint analysis of family and case-control data

    Directory of Open Access Journals (Sweden)

    Gray-McGuire Courtney


    Full Text Available Abstract With the trend in molecular epidemiology towards both genome-wide association studies and complex modelling, the need for large sample sizes to detect small effects and to allow for the estimation of many parameters within a model continues to increase. Unfortunately, most methods of association analysis have been restricted to either a family-based or a case-control design, resulting in the lack of synthesis of data from multiple studies. Transmission disequilibrium-type methods for detecting linkage disequilibrium from family data were developed as an effective way of preventing the detection of association due to population stratification. Because these methods condition on parental genotype, however, they have precluded the joint analysis of family and case-control data, although methods for case-control data may not protect against population stratification and do not allow for familial correlations. We present here an extension of a family-based association analysis method for continuous traits that will simultaneously test for, and if necessary control for, population stratification. We further extend this method to analyse binary traits (and therefore family and case-control data together and accurately to estimate genetic effects in the population, even when using an ascertained family sample. Finally, we present the power of this binary extension for both family-only and joint family and case-control data, and demonstrate the accuracy of the association parameter and variance components in an ascertained family sample.

  19. Online Optimization-Based Predictive Flight Control Using First-Order Methods

    NARCIS (Netherlands)

    Ferranti, L.


    In fields such as aerospace or automotive, the use of classical control methods such as PID is still significant. The presence of constraints, however, impacts on the performance of these controllers that are usually designed to avoid constraint saturation. MPC techniques are the obvious alternative

  20. A Comparative Study of Item Exposure Control Methods in Computerized Adaptive Testing. (United States)

    Chang, Shun-Wen; Twu, Bor-Yaun

    This study investigated and compared the properties of five methods of item exposure control within the purview of estimating examinees' abilities in a computerized adaptive testing (CAT) context. Each of the exposure control algorithms was incorporated into the item selection procedure and the adaptive testing progressed based on the CAT design…

  1. A simple method for the quality control of [(18)F]FDG

    DEFF Research Database (Denmark)

    Koziorowski, J


    Most automated synthesis modules produce [(18)F]FDG within half an hour, but the quality control involving up to three separate methods and three different analytical systems is time consuming. The use of HPLC, TLC, and GC for the quality control of [(18)F]FDG is both time consuming and expensive...

  2. A Hybrid Optimization Method for Reactive Power and Voltage Control Considering Power Loss Minimization

    DEFF Research Database (Denmark)

    Liu, Chengxi; Qin, Nan; Bak, Claus Leth


    This paper proposes a hybrid optimization method to optimally control the voltage and reactive power with minimum power loss in transmission grid. This approach is used for the Danish automatic voltage control (AVC) system which is typically a non-linear non-convex problem mixed with both...

  3. Expert methods in control systems of deep oil and gas holes building

    Energy Technology Data Exchange (ETDEWEB)

    Sementsov, G.; Fadeeva, I.; Chigur, I. [State Technical Univ. of Oil and Gas, Ivano-Frankivsk (Ukraine)


    Attempts to provide self-control of process of long holing on oil and gas have not given due effect owing to complication of object, it fuzzy and equivocation of the information. In this connection it is offered to use for management of drilling expert systems, which one use fuzzy models and methods of the theory of fuzzy control systems. (orig.)

  4. Hybrid Intelligent Control Method to Improve the Frequency Support Capability of Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Shin Young Heo


    Full Text Available This paper presents a hybrid intelligent control method that enables frequency support control for permanent magnet synchronous generators (PMSGs wind turbines. The proposed method for a wind energy conversion system (WECS is designed to have PMSG modeling and full-scale back-to-back insulated-gate bipolar transistor (IGBT converters comprising the machine and grid side. The controller of the machine side converter (MSC and the grid side converter (GSC are designed to achieve maximum power point tracking (MPPT based on an improved hill climb searching (IHCS control algorithm and de-loaded (DL operation to obtain a power margin. Along with this comprehensive control of maximum power tracking mode based on the IHCS, a method for kinetic energy (KE discharge control of the supporting primary frequency control scheme with DL operation is developed to regulate the short-term frequency response and maintain reliable operation of the power system. The effectiveness of the hybrid intelligent control method is verified by a numerical simulation in PSCAD/EMTDC. Simulation results show that the proposed approach can improve the frequency regulation capability in the power system.

  5. An empirical framework of control methods of victims of human trafficking for sexual exploitation

    NARCIS (Netherlands)

    Ioannou, Maria; Oostinga, Miriam Sharon Daniëlle


    Although human trafficking for sexual exploitation is a frequently discussed area in current research, especially on the way that human traffickers control their victims, a recurrent problem is the lack of empirical basis. The present study examines control methods (or conditions) used against 137

  6. Control Methods of the Switched Reluctance Motor in Electric Vehicle During Acceleration

    Directory of Open Access Journals (Sweden)

    Fathy El Sayed ABDEL-KADER


    Full Text Available In this paper, the equations describing the performance of the electric vehicle are derived. Performance characteristics for each part in the vehicle system are obtained when the vehicle is accelerated under voltage, turn on and turn off angle control. A comparison between the different methods of control is established.

  7. Course Control of Underactuated Ship Based on Nonlinear Robust Neural Network Backstepping Method. (United States)

    Yuan, Junjia; Meng, Hao; Zhu, Qidan; Zhou, Jiajia


    The problem of course control for underactuated surface ship is addressed in this paper. Firstly, neural networks are adopted to determine the parameters of the unknown part of ideal virtual backstepping control, even the weight values of neural network are updated by adaptive technique. Then uniform stability for the convergence of course tracking errors has been proven through Lyapunov stability theory. Finally, simulation experiments are carried out to illustrate the effectiveness of proposed control method.

  8. Cooperative system and method using mobile robots for testing a cooperative search controller (United States)

    Byrne, Raymond H.; Harrington, John J.; Eskridge, Steven E.; Hurtado, John E.


    A test system for testing a controller provides a way to use large numbers of miniature mobile robots to test a cooperative search controller in a test area, where each mobile robot has a sensor, a communication device, a processor, and a memory. A method of using a test system provides a way for testing a cooperative search controller using multiple robots sharing information and communicating over a communication network.

  9. Parental control over feeding in infancy. Influence of infant weight, appetite and feeding method


    Fildes, Alison; van Jaarsveld, Cornelia H. M.; Llewellyn, Clare; Wardle, Jane; Fisher, Abigail


    Background and objective: Parental control over feeding has been linked to child overweight. Parental control behaviours have been assumed to be exogenous to the child, but emerging evidence suggests they are also child-responsive. This study tests the hypothesis that parental control in early infancy is responsive to infant appetite and weight. Subjects and methods: Participants were 1920 mothers from the Gemini twin cohort, using one randomly selected child per family. Data come from questi...

  10. An alternate method for achieving temperature control in the -130 C to 75 C range (United States)

    Johnson, Kenneth R.; Anderson, Mark R.; Lane, Robert W.; Cortez, Maximo G.


    Thermal vacuum testing often requires temperature control of chamber shrouds and heat exchangers within the -130 C to 75 C range. There are two conventional methods which are normally employed to achieve control through this intermediate temperature range: (1) single-pass flow where control is achieved by alternately pulsing hot gaseous nitrogen (GN2) and cold LN2 into the feed line to yield the setpoint temperature; and (2) closed-loop circulation where control is achieved by either electrically heating or LN2 cooling the circulating GN2 to yield the setpoint temperature. A third method, using a mass flow ratio controller along with modulating control valves on GN2 and LN2 lines, provides excellent control but equipment for this method is expensive and cost-prohibitive for all but long-term continuous processes. The single-pass method provides marginal control and can result in unexpected overcooling of the test article from even a short pulse of LN2. The closed-loop circulation method provides excellent control but requires an expensive blower capable of operating at elevated pressures and cryogenic temperatures. Where precise control is needed (plus or minus 2 C), single-pass flow systems typically have not provided the precision required, primarily because of overcooling temperature excursions. Where several individual circuits are to be controlled at different temperatures, the use of expensive cryogenic blowers for each circuit is also cost-prohibitive, especially for short duration of one-of-a-kind tests. At JPL, a variant of the single-pass method was developed that was shown to provide precise temperature control in the -130 C to 75 C range while exhibiting minimal setpoint overshoot during temperature transitions. This alternate method uses a commercially available temperature controller along with a GN2/LN2 mixer to dampen the amplitude of cold temperature spikes caused by LN2 pulsing. The design of the GN2/LN2 mixer, the overall control system

  11. An alternate method for achieving temperature control in the -130 C to 75 C range (United States)

    Johnson, Kenneth R.; Anderson, Mark R.; Lane, Robert W.; Cortez, Maximo G.


    Thermal vacuum testing often requires temperature control of chamber shrouds and heat exchangers within the -130 C to 75 C range. There are two conventional methods which are normally employed to achieve control through this intermediate temperature range: (1) single-pass flow where control is achieved by alternately pulsing hot gaseous nitrogen (GN2) and cold LN2 into the feed line to yield the setpoint temperature; and (2) closed-loop circulation where control is achieved by either electrically heating or LN2 cooling the circulating GN2 to yield the setpoint temperature. A third method, using a mass flow ratio controller along with modulating control valves on GN2 and LN2 lines, provides excellent control but equipment for this method is expensive and cost-prohibitive for all but long-term continuous processes. The single-pass method provides marginal control and can result in unexpected overcooling of the test article from even a short pulse of LN2. The closed-loop circulation method provides excellent control but requires an expensive blower capable of operating at elevated pressures and cryogenic temperatures. Where precise control is needed (plus or minus 2 C), single-pass flow systems typically have not provided the precision required, primarily because of overcooling temperature excursions. Where several individual circuits are to be controlled at different temperatures, the use of expensive cryogenic blowers for each circuit is also cost-prohibitive, especially for short duration of one-of-a-kind tests. At JPL, a variant of the single-pass method was developed that was shown to provide precise temperature control in the -130 C to 75 C range while exhibiting minimal setpoint overshoot during temperature transitions. This alternate method uses a commercially available temperature controller along with a GN2/LN2 mixer to dampen the amplitude of cold temperature spikes caused by LN2 pulsing. The design of the GN2/LN2 mixer, the overall control system

  12. Dynamic Exergy Method for Evaluating the Control and Operation of Oxy-Combustion Boiler Island Systems. (United States)

    Jin, Bo; Zhao, Haibo; Zheng, Chuguang; Liang, Zhiwu


    Exergy-based methods are widely applied to assess the performance of energy conversion systems; however, these methods mainly focus on a certain steady-state and have limited applications for evaluating the control impacts on system operation. To dynamically obtain the thermodynamic behavior and reveal the influences of control structures, layers and loops, on system energy performance, a dynamic exergy method is developed, improved, and applied to a complex oxy-combustion boiler island system for the first time. The three most common operating scenarios are studied, and the results show that the flow rate change process leads to less energy consumption than oxygen purity and air in-leakage change processes. The variation of oxygen purity produces the largest impact on system operation, and the operating parameter sensitivity is not affected by the presence of process control. The control system saves energy during flow rate and oxygen purity change processes, while it consumes energy during the air in-leakage change process. More attention should be paid to the oxygen purity change because it requires the largest control cost. In the control system, the supervisory control layer requires the greatest energy consumption and the largest control cost to maintain operating targets, while the steam control loops cause the main energy consumption.

  13. Silicon microgyroscope temperature prediction and control system based on BP neural network and Fuzzy-PID control method (United States)

    Xia, Dunzhu; Kong, Lun; Hu, Yiwei; Ni, Peizhen


    We present a novel silicon microgyroscope (SMG) temperature prediction and control system in a narrow space. As the temperature of SMG is closely related to its drive mode frequency and driving voltage, a temperature prediction model can be established based on the BP neural network. The simulation results demonstrate that the established temperature prediction model can estimate the temperature in the range of -40 to 60 °C with an error of less than ±0.05 °C. Then, a temperature control system based on the combination of fuzzy logic controller and the increment PID control method is proposed. The simulation results prove that the Fuzzy-PID controller has a smaller steady state error, less rise time and better robustness than the PID controller. This is validated by experimental results that show the Fuzzy-PID control method can achieve high precision in keeping the SMG temperature stable at 55 °C with an error of less than 0.2 °C. The scale factor can be stabilized at 8.7 mV/°/s with a temperature coefficient of 33 ppm °C-1. ZRO (zero rate output) instability is decreased from 1.10°/s (9.5 mV) to 0.08°/s (0.7 mV) when the temperature control system is implemented over an ambient temperature range of -40 to 60 °C.

  14. A Review of External Pressure Testing Techniques for Shells including a Novel Volume-Control Method

    NARCIS (Netherlands)

    Mackay, J.R.; Van Keulen, F.


    A review of conventional testing methods for applying external hydrostatic pressure to buckling-critical shells is presented. A new “volume-control” pressure testing method, aimed at preventing catastrophic specimen failures and improving control of specimen deformation near the critical load, is

  15. A control volume based finite difference method for solving the equilibrium equations in terms of displacements

    DEFF Research Database (Denmark)

    Hattel, Jesper; Hansen, Preben


    This paper presents a novel control volume based FD method for solving the equilibrium equations in terms of displacements, i.e. the generalized Navier equations. The method is based on the widely used cv-FDM solution of heat conduction and fluid flow problems involving a staggered grid formulation...

  16. New 2DOF PI and PID Controllers Tuning Method for Integrating Plants

    Directory of Open Access Journals (Sweden)

    Miluše VÍTEČKOVÁ


    Full Text Available The paper deals with a new 2DOF PI and PID controllers tuning method for integrating plants. The described approach is derived from the multiple dominant pole method and it enables the achievement of an aperiodic servo and regulatory step responses.

  17. System and method to control h2o2 level in advanced oxidation processes

    DEFF Research Database (Denmark)


    The present invention relates to a bio-electrochemical system (BES) and a method of in-situ production and removal of H2O2 using such a bio-electrochemical system (BES). Further, the invention relates to a method for in-situ control of H2O2 content in an aqueous system of advanced oxidation...

  18. A Method for Precision Closed-Loop Irrigation Using a Modified PID Control Algorithm (United States)

    Goodchild, Martin; Kühn, Karl; Jenkins, Malcolm; Burek, Kazimierz; Dutton, Andrew


    The benefits of closed-loop irrigation control have been demonstrated in grower trials which show the potential for improved crop yields and resource usage. Managing water use by controlling irrigation in response to soil moisture changes to meet crop water demands is a popular approach but requires knowledge of closed-loop control practice. In theory, to obtain precise closed-loop control of a system it is necessary to characterise every component in the control loop to derive the appropriate controller parameters, i.e. proportional, integral & derivative (PID) parameters in a classic PID controller. In practice this is often difficult to achieve. Empirical methods are employed to estimate the PID parameters by observing how the system performs under open-loop conditions. In this paper we present a modified PID controller, with a constrained integral function, that delivers excellent regulation of soil moisture by supplying the appropriate amount of water to meet the needs of the plant during the diurnal cycle. Furthermore, the modified PID controller responds quickly to changes in environmental conditions, including rainfall events which can result in: controller windup, under-watering and plant stress conditions. The experimental work successfully demonstrates the functionality of a constrained integral PID controller that delivers robust and precise irrigation control. Coir substrate strawberry growing trial data is also presented illustrating soil moisture control and the ability to match water deliver to solar radiation.

  19. Analysis of Nested Case-Control Study Designs: Revisiting the Inverse Probability Weighting Method. (United States)

    Kim, Ryung S


    In nested case-control studies, the most common way to make inference under a proportional hazards model is the conditional logistic approach of Thomas (1977). Inclusion probability methods are more efficient than the conditional logistic approach of Thomas; however, the epidemiology research community has not accepted the methods as a replacement of the Thomas' method. This paper promotes the inverse probability weighting method originally proposed by Samuelsen (1997) in combination with an approximate jackknife standard error that can be easily computed using existing software. Simulation studies demonstrate that this approach yields valid type 1 errors and greater powers than the conditional logistic approach in nested case-control designs across various sample sizes and magnitudes of the hazard ratios. A generalization of the method is also made to incorporate additional matching and the stratified Cox model. The proposed method is illustrated with data from a cohort of children with Wilm's tumor to study the association between histological signatures and relapses.

  20. Comparison of bar pattern and edge method for MTF measurement in radiology quality control

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, M.; Alves, A.F.F; Bacchim Neto, F.A.; Pavan, A.L.M.; Rosa, M.E.D.; Miranda, J.R.A.; Pina, D.R. de, E-mail: [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil)


    Spatial resolution is one of the parameters that is routinely checked during acceptance procedures and regular quality control measurements. The spatial resolution of a radiographic imaging device is most appropriately expressed in terms of its modulation transfer function (MTF), which indicates the decline of detector spatial resolution with spatial frequency. Traditionally used methods of MTF measurement involve imaging either a narrow slit or a sharp edge to obtain the detector line spread function (LSF), whose frequency transform leads to the MTF. In this work is presented a study of the measurement of the limiting spatial resolution using the MTF method and the line-pair bar-pattern method. Our aim is to compare the bar-pattern method with the MTF method and then evaluate what method is the best for the dairy quality control tests and when is better to perform one test or other. These acquisition procedures were tested according to its reproducibility and variation due to noise. (author)

  1. A discontinuous control volume finite element method for multi-phase flow in heterogeneous porous media (United States)

    Salinas, P.; Pavlidis, D.; Xie, Z.; Osman, H.; Pain, C. C.; Jackson, M. D.


    We present a new, high-order, control-volume-finite-element (CVFE) method for multiphase porous media flow with discontinuous 1st-order representation for pressure and discontinuous 2nd-order representation for velocity. The method has been implemented using unstructured tetrahedral meshes to discretize space. The method locally and globally conserves mass. However, unlike conventional CVFE formulations, the method presented here does not require the use of control volumes (CVs) that span the boundaries between domains with differing material properties. We demonstrate that the approach accurately preserves discontinuous saturation changes caused by permeability variations across such boundaries, allowing efficient simulation of flow in highly heterogeneous models. Moreover, accurate solutions are obtained at significantly lower computational cost than using conventional CVFE methods. We resolve a long-standing problem associated with the use of classical CVFE methods to model flow in highly heterogeneous porous media.

  2. Chaos control and function projective synchronization of fractional-order systems through the backstepping method (United States)

    Das, S.; Yadav, V. K.


    We study the chaos control and the function projective synchronization of a fractional-order T-system and Lorenz chaotic system using the backstepping method. Based on stability theory, we consider the condition for the local stability of nonlinear three-dimensional commensurate fractional-order system. Using the feedback control method, we control the chaos in the considered fractional-order T-system. We simulate the function projective synchronization between the fractional-order T-system and Lorenz system numerically using MATLAB and depict the results with plots.

  3. Robust H-infinity control synthesis method and its application to benchmark problems (United States)

    Wie, Bong; Liu, Qiang; Byun, Kuk-Whan


    This paper presents a robust H-infinity control synthesis method for structured parameter uncertainty. The robust H-infinity control design methodology is also incorporated with the so-called internal model principle for persistent-disturbance rejection. A noncollocated control problem of flexible space structures subject to parameter variations is used to illustrate the design methodology. It is shown that the proposed design method invariably makes use of nonminimum-phase compensation and that it achieves the desired asymptotic disturbance rejection by having a disturbance rejection 'dipole'.

  4. Boundary control and tomography of Riemannian manifolds (the BC-method) (United States)

    Belishev, M. I.


    The BC-method provides one of the approaches to inverse problems of mathematical physics. A characteristic feature of this method is the great variety of interdisciplinary relations involved: in addition to partial differential equations as a source of problems, use is made of control theory and systems theory, asymptotic methods, functional analysis, operator theory, Banach algebras, and so on. The purpose of this paper is to present the principal ideas and tools of the BC-method and to give a survey of some results. One of the main achievements of the method is chosen for presentation: the reconstruction of Riemannian manifolds from dynamical and spectral boundary data. Bibliography: 108 titles.

  5. Control Systems for Hyper-Redundant Robots Based on Artificial Potential Method

    Directory of Open Access Journals (Sweden)

    Mihaela Florescu


    Full Text Available This paper presents the control method of hyper-redundant robots based on the artificial potential approach. The principles of this method are shown and a suggestive example is offered. Then, the artificial potential method is applied to the case of a tentacle robot starting from the dynamic model of the robot. In addition, a series of results that are obtained through simulation is presented.

  6. Kinetic studies in solid state reactions by sample-controlled methods and advanced analysis procedures


    Pérez-Maqueda, Luis A.; Criado, J. M.; Sánchez-Jiménez, P.E.; Perejón, Antonio


    A comparative study of both conventional rising temperature and sample-controlled methods, like constant rate thermal analysis (CRTA), is carried out after analyzing a set of solid state reactions using both methods. It is shown that CRTA avoids the influence of heat and mass transfer phenomena for a wide range of sample sizes leading to reliable kinetic parameters. On the other hand, conventional rising temperature methods yield α–T plots dependent on experimental conditions, even when using...

  7. Simulation of marine controlled source electromagnetic measurements using a parallel fourier hp-finite element method


    Pardo D.; Nam M.J.; Torres-Verdín C.; Hoversten M.G.; Garay Iñ.


    We introduce a new numerical method to simulate geophysical marine controlled source electromagnetic (CSEM) measurements for the case of 2D structures and finite 3D sources of electromagnetic (EM) excitation. The method of solution is based on a spatial discretization that combines a 1D Fourier transform with a 2D self-adaptive, goal-oriented, hp-Finite element method. It enables fast and accurate simulations for a variety of important, challenging and practical cases of marine CSEM acquisiti...

  8. A symplectic pseudospectral method for nonlinear optimal control problems with inequality constraints. (United States)

    Wang, Xinwei; Peng, Haijun; Zhang, Sheng; Chen, Biaosong; Zhong, Wanxie


    A symplectic pseudospectral method based on the dual variational principle and the quasilinearization method is proposed and is successfully applied to solve nonlinear optimal control problems with inequality constraints in this paper. Nonlinear optimal control problem is firstly converted into a series of constraint linear-quadratic optimal control problems with the help of quasilinearization techniques. Then a symplectic pseudospectral method based on dual variational principle for solving the converted constrained linear-quadratic optimal control problems is developed. In the proposed method, inequality constraints which can be functions of pure state, pure control and mixed state-control are transformed into equality constraints with the help of parameteric variables. After that, state variables, costate variables and parametric variables are interpolated locally at Legendre-Gauss-Lobatto points. Finally, based on the parametric variational principle and complementary conditions, the converted problem is transformed into a standard linear complementary problem which can be solved easily. Numerical examples show that the proposed method is of high accuracy and efficiency. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  9. Developing of method for primary frequency control droop and deadband actual values estimation (United States)

    Nikiforov, A. A.; Chaplin, A. G.


    Operation of thermal power plant generation equipment, which participates in standardized primary frequency control (SPFC), must meet specific requirements. These requirements are formalized as nine algorithmic criteria, which are used for automatic monitoring of power plant participation in SPFC. One of these criteria - primary frequency control droop and deadband actual values estimation is considered in detail in this report. Experience shows that existing estimation method sometimes doesn’t work properly. Author offers alternative method, which allows estimating droop and deadband actual values more accurately. This method was implemented as a software application.

  10. Fabrication of advanced Bragg gratings with complex apodization profiles by use of the polarization control method

    DEFF Research Database (Denmark)

    Deyerl, Hans-Jürgen; Plougmann, Nikolai; Jensen, Jesper Bo Damm


    The polarization control method offers a flexible, robust, and low-cost route for the parallel fabrication of gratings with complex apodization profiles including several discrete phase shifts and chirp. The performance of several test gratings is evaluated in terms of their spectral response...... and compared with theoretical predictions. Short gratings with sidelobe-suppression levels in excess of 32 dB and transmission dips lower than 80 dB have been realized. Finally, most of the devices fabricated by the polarization control method show comparable quality to gratings manufactured by far more...... complex methods....

  11. A novel auto-tuning method for fractional order PI/PD controllers. (United States)

    De Keyser, Robin; Muresan, Cristina I; Ionescu, Clara M


    Fractional order PID controllers benefit from an increasing amount of interest from the research community due to their proven advantages. The classical tuning approach for these controllers is based on specifying a certain gain crossover frequency, a phase margin and a robustness to gain variations. To tune the fractional order controllers, the modulus, phase and phase slope of the process at the imposed gain crossover frequency are required. Usually these values are obtained from a mathematical model of the process, e.g. a transfer function. In the absence of such model, an auto-tuning method that is able to estimate these values is a valuable alternative. Auto-tuning methods are among the least discussed design methods for fractional order PID controllers. This paper proposes a novel approach for the auto-tuning of fractional order controllers. The method is based on a simple experiment that is able to determine the modulus, phase and phase slope of the process required in the computation of the controller parameters. The proposed design technique is simple and efficient in ensuring the robustness of the closed loop system. Several simulation examples are presented, including the control of processes exhibiting integer and fractional order dynamics. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  12. A Nonlinear Physics-Based Optimal Control Method for Magnetostrictive Actuators (United States)

    Smith, Ralph C.


    This paper addresses the development of a nonlinear optimal control methodology for magnetostrictive actuators. At moderate to high drive levels, the output from these actuators is highly nonlinear and contains significant magnetic and magnetomechanical hysteresis. These dynamics must be accommodated by models and control laws to utilize the full capabilities of the actuators. A characterization based upon ferromagnetic mean field theory provides a model which accurately quantifies both transient and steady state actuator dynamics under a variety of operating conditions. The control method consists of a linear perturbation feedback law used in combination with an optimal open loop nonlinear control. The nonlinear control incorporates the hysteresis and nonlinearities inherent to the transducer and can be computed offline. The feedback control is constructed through linearization of the perturbed system about the optimal system and is efficient for online implementation. As demonstrated through numerical examples, the combined hybrid control is robust and can be readily implemented in linear PDE-based structural models.

  13. Model Reference Adaptive Control of the Air Flow Rate of Centrifugal Compressor Using State Space Method

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jaeyoung; Jung, Mooncheong; Yu, Sangseok [Chungnam Nat’l Univ., Daejeon (Korea, Republic of); Yi, Sun [North Carolina A and T State Univ., Raleigh (United States)


    In this study, a model reference adaptive controller is developed to regulate the outlet air flow rate of centrifugal compressor for automotive supercharger. The centrifugal compressor is developed using the analytical based method to predict the transient behavior of operating and the designed model is validated with experimental data to confirm the system accuracy. The model reference adaptive control structure consists of a compressor model and a MRAC(model reference adaptive control) mechanism. The feedback control do not robust with variation of system parameter but the applied adaptive control is robust even if the system parameter is changed. As a result, the MRAC was regulated to reference air flow rate. Also MRAC was found to be more robust control compared with the feedback control even if the system parameter is changed.

  14. A Secondary Voltage Control Method for an AC/DC Coupled Transmission System Based on Model Predictive Control

    DEFF Research Database (Denmark)

    Xu, Fengda; Guo, Qinglai; Sun, Hongbin


    to keep the voltage of the pilot bus tracking its set point considering the DC system’s transmission schedule change. The approach is inspired by model predictive control (MPC) to compensate for predictable voltage change affected by DC side transmission power flow and the potential capacitor switching......For an AC/DC coupled transmission system, the change of transmission power on the DC lines will significantly influence the AC systems’ voltage. This paper describes a method to coordinated control the reactive power of power plants and shunt capacitors at DC converter stations nearby, in order...

  15. Control valve and control valve system for controlling solids flow, methods of manufacture thereof and articles comprising the same

    Energy Technology Data Exchange (ETDEWEB)

    Jukkola, Glen D.; Teigen, Bard C.


    Disclosed herein is a solids flow control valve comprising a standpipe; a shoe; and a transport pipe; wherein the standpipe is in operative communication with the shoe and lies upstream of the shoe; the standpipe comprising a first end and a second end, where the first end is in contact with a source that contains disposable solids and the second end is in fluid contact with the shoe; the shoe being operative to restrict the flow of the disposable solids; the transport pipe being disposed downstream of the shoe to receive and transport the solids from the shoe.

  16. A Control Method for Maximum Power Point Tracking in Stand-Alone-Type PV Generation Systems (United States)

    Itako, Kazutaka; Mori, Takeaki

    In this paper, a new control method for maximum power point tracking (MPPT) in stand-alone-type PV generaton systems is proposed. In this control method, the operations detecting the maximum power point and tracking its point are alternately carried out by using a step-up DC—DC converter. This method requires neither the measurement of temperature and insolation level nor PV array model. In a stand-alone-type application with a battery load, the design method for the boost inductance L of the step-up DC—DC converter is described, and the experimental results show that the use of the proposed MPPT control increases the PV generated energy by 14.8% compared to the conventional system.

  17. Path Tracking Controller of Quadruped Robot for Obstacle Avoidance Using Potential Functions Method

    Directory of Open Access Journals (Sweden)

    Giang Hoang


    Full Text Available This paper proposes a tracking controller for obstacle avoidance of a quadruped robot using potential functions method. The followings are done for this task. At first, a ceiling-mounted camera system is installed for image processing. The goal point and obstacles are separated and recognized by a color recognition method. Second, a path planning algorithm using potential functions method is proposed to generate the path to avoid obstacles and to plan a path for the quadruped robot to reach from start point to goal point. Third, a quadruped robot is chosen as the mobile platform for this study and the kinematic model for the robot is presented. Fourth, a tracking controller is designed for the quadruped robot to track the trajectory based on the backstepping method using Lyapunov function. Finally, the simulation results are presented to show the effectiveness of the proposed trajectory planning algorithm and the tracking controller.

  18. Control of plutonium content using a concept of physical accounting method for adjusted fissile enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Nakae, Nobuo; Ito, Masanori; Mishima, Tsuyoshi; Shiina, Akira.


    In Fast Breeder Reactor (FBR), plutonium is used as main fissile material. Plutonium has the following characteristics with respect to reactor reactivity. (1) Plutonium is obtained by reprocessing of spent fuels. The plutonium isotope ratio depends on the burn-up of the spent fuels. (2) Pu-241 which is one of the major Plutonium isotopes lose reactivity quickly with the disintegration to Am-241. (3) Each plutonium isotope has considerably different effect on reactor reactivity. A concept of physical accounting method for adjusted fissile enrichment has been introduced in controlling plutonium content of the fuel loaded into PNC's Monju reactor. The method enables exact control of the fresh fuel's reactivity. In this report basic concept of the method, plutonium content control in a fuel fabrication line based on the method and the simulation result are explained. (author).

  19. Resistance Torque Based Variable Duty-Cycle Control Method for a Stage II Compressor (United States)

    Zhong, Meipeng; Zheng, Shuiying


    The resistance torque of a piston stage II compressor generates strenuous fluctuations in a rotational period, and this can lead to negative influences on the working performance of the compressor. To restrain the strenuous fluctuations in the piston stage II compressor, a variable duty-cycle control method based on the resistance torque is proposed. A dynamic model of a stage II compressor is set up, and the resistance torque and other characteristic parameters are acquired as the control targets. Then, a variable duty-cycle control method is applied to track the resistance torque, thereby improving the working performance of the compressor. Simulated results show that the compressor, driven by the proposed method, requires lower current, while the rotating speed and the output torque remain comparable to the traditional variable-frequency control methods. A variable duty-cycle control system is developed, and the experimental results prove that the proposed method can help reduce the specific power, input power, and working noise of the compressor to 0.97 kW·m-3·min-1, 0.09 kW and 3.10 dB, respectively, under the same conditions of discharge pressure of 2.00 MPa and a discharge volume of 0.095 m3/min. The proposed variable duty-cycle control method tracks the resistance torque dynamically, and improves the working performance of a Stage II Compressor. The proposed variable duty-cycle control method can be applied to other compressors, and can provide theoretical guidance for the compressor.

  20. High Performance Low Cost Digitally Controlled Power Conversion Technology

    DEFF Research Database (Denmark)

    Jakobsen, Lars Tønnes


    suited for digital control schemes involving multiple control loops such as digital control of a switch-mode power supply with several converter stages. Customised digital control solutions implemented in application specific integrated circuits are the best solution for high bandwidth digital control......Digital control of switch-mode power supplies and converters has within the last decade evolved from being an academic subject to an emerging market in the power electronics industry. This development has been pushed mainly by the computer industry that is looking towards digital power management...... of non-isolated DC-DC converters. A customised digital control solution for a voltage mode control scheme should include a digital pulse width modulator which can generate a pulse width modulated signal with high switching frequency and high resolution, a digital compensator with a short execution time...

  1. A frequency response model matching method for PID controller design for processes with dead-time. (United States)

    Anwar, Md Nishat; Pan, Somnath


    In this paper, a PID controller design method for the integrating processes based on frequency response matching is presented. Two approaches are proposed for the controller design. In the first approach, a double feedback loop configuration is considered where the inner loop is designed with a stabilizing gain. In the outer loop, the parameters of the PID controller are obtained by frequency response matching between the closed-loop system with the PID controller and a reference model with desired specifications. In the second approach, the design is directly carried out considering a desired load-disturbance rejection model of the system. In both the approaches, two low frequency points are considered for matching the frequency response, which yield linear algebraic equations, solution of which gives the controller parameters. Several examples are taken from the literature to demonstrate the effectiveness and to compare with some well known design methods. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  2. Stability Control of Propeller Autonomous Underwater Vehicle Based on Combined Sections Method

    Directory of Open Access Journals (Sweden)

    Qi Duo


    Full Text Available Learning from the motion principle of quadrotor, a symmetric propeller AUV, which has small size and low velocity is designed. Compared with the AUV equipped with rudders, it has better maneuverability and manipulation at low velocity. According to the Newton-Euler method, the 6 DOF kinematic model and dynamic model of the propeller AUV are established. A stability controller that consists of 3 different PID controllers is designed. It makes the depth and attitude angle as trigger conditions, and the relevant controller is chosen in different moving process. The simulation experiments simulate ideal motion state and disturbed motion state, and experiments results show that the stability controller based on combined sections method can make the best of mature technology of PID, and meet the control requirements in different stages. It has a higher respond speed and accuracy, improving the stability of the propeller AUV under the disturbance of complex ocean currents.

  3. Vector control method applied to a traveling wave in a finite beam. (United States)

    Giraud, Frédéric; Giraud-Audine, Christophe; Amberg, Michel; Lemaire-Semail, Betty


    This paper presents the closed-loop control of exciters to produce a traveling wave in a finite beam. This control is based on a dynamical modeling of the system established in a rotating reference frame. This method allows dynamic and independent control of the phase and amplitude of two vibration modes. The condition to obtain the traveling wave is written in this rotating frame, and requires having two vibration modes with the same amplitude, and imposing a phase shift of 90° between them. The advantage of the method is that it allows easy implementation of a closed loop control that can handle parameter drift of the system, after a temperature rise, for example. The modeling is compared with measurement on an experimental test bench which also implements real-time control. We managed to experimentally obtain a settling time of 250 ms for the traveling wave, and a standing wave ratio (SWR) of 1.3.

  4. Study on frequency control method for DBR laser diode based on FPGA (United States)

    Hao, Jiepeng; Hong, Jintao; Chen, Linlin; Lei, Guanqun; Zhou, Binquan


    In recent years, the distributed Bragg reflector (DBR) laser diode (LD) has advantages of its small size, high efficiency, low power consumption and so on, so it has been widely used in precision measurement, optical information processing, quantum research and other fields. There is a strict requirement for the output frequency of the DBR laser diode in precision measurement technology. Therefore, controlling the frequency of the laser accurately is of great significance for precision measurement. Currently, there are a lot of frequency control scheme for laser diode, mainly through the external system to stabilize the frequency of laser diode, the drawback of which is that it is not conducive to system integration. Therefore, this paper proposes a method based on FPGA for controlling the output frequency of the laser diode. The main purpose of the control is to study the frequency characteristics of the laser diode. In this paper, the FPGA chip is used as a micro controller, and combined with PID control algorithm constitute a closed loop control circuit. At the same time, the control algorithm is programmed into the FPGA device, which can maximize the operating speed of control system. For different frequency of the laser, it is only required to modify the control parameters simply, which can be realized the steady control of the light source. Through the test, near the operating temperature of the laser diode, temperature stability is better than +/-0.01°C. As a result, the laser frequency stability can be controlled to 0.1%.

  5. Design of a micro-irrigation system based on the control volume method

    Directory of Open Access Journals (Sweden)

    Chasseriaux G.


    Full Text Available A micro-irrigation system design based on control volume method using the back step procedure is presented in this study. The proposed numerical method is simple and consists of delimiting an elementary volume of the lateral equipped with an emitter, called « control volume » on which the conservation equations of the fl uid hydrodynamicʼs are applied. Control volume method is an iterative method to calculate velocity and pressure step by step throughout the micro-irrigation network based on an assumed pressure at the end of the line. A simple microcomputer program was used for the calculation and the convergence was very fast. When the average water requirement of plants was estimated, it is easy to choose the sum of the average emitter discharge as the total average fl ow rate of the network. The design consists of exploring an economical and effi cient network to deliver uniformly the input fl ow rate for all emitters. This program permitted the design of a large complex network of thousands of emitters very quickly. Three subroutine programs calculate velocity and pressure at a lateral pipe and submain pipe. The control volume method has already been tested for lateral design, the results from which were validated by other methods as fi nite element method, so it permits to determine the optimal design for such micro-irrigation network

  6. A Pressure Control Method for Emulsion Pump Station Based on Elman Neural Network

    Directory of Open Access Journals (Sweden)

    Chao Tan


    Full Text Available In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others.

  7. A method of reactor power decrease by 2DOF control system during BWR power oscillation

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, Nobuyuki; Suzuki, Katsuo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment


    Occurrence of power oscillation events caused by void feedback effects in BWRs operated at low-flow and high-power condition has been reported. After thoroughly examining these events, BWRs have been equipped with the SRI (Selected Rod Insertion) system to avoid the power oscillation by decreasing the power under such reactor condition. This report presents a power control method for decreasing the reactor power stably by a two degree of freedom (2DOF) control. Performing a numerical simulation by utilizing a simple reactor dynamics model, it is found that the control system designed attains a satisfactory control performance of power decrease from a viewpoint of setting time and oscillation. (author)

  8. Method and apparatus for actively controlling a micro-scale flexural plate wave device (United States)

    Dohner, Jeffrey L.


    An actively controlled flexural plate wave device provides a micro-scale pump. A method of actively controlling a flexural plate wave device produces traveling waves in the device by coordinating the interaction of a magnetic field with actively controlled currents. An actively-controlled flexural plate wave device can be placed in a fluid channel and adapted for use as a micro-scale fluid pump to cool or drive micro-scale systems, for example, micro-chips, micro-electrical-mechanical devices, micro-fluid circuits, or micro-scale chemical analysis devices.

  9. An Analysis of Variable-Speed Wind Turbine Power-Control Methods with Fluctuating Wind Speed

    Directory of Open Access Journals (Sweden)

    Seung-Il Moon


    Full Text Available Variable-speed wind turbines (VSWTs typically use a maximum power-point tracking (MPPT method to optimize wind-energy acquisition. MPPT can be implemented by regulating the rotor speed or by adjusting the active power. The former, termed speed-control mode (SCM, employs a speed controller to regulate the rotor, while the latter, termed power-control mode (PCM, uses an active power controller to optimize the power. They are fundamentally equivalent; however, since they use a different controller at the outer control loop of the machine-side converter (MSC controller, the time dependence of the control system differs depending on whether SCM or PCM is used. We have compared and analyzed the power quality and the power coefficient when these two different control modes were used in fluctuating wind speeds through computer simulations. The contrast between the two methods was larger when the wind-speed fluctuations were greater. Furthermore, we found that SCM was preferable to PCM in terms of the power coefficient, but PCM was superior in terms of power quality and system stability.

  10. A method for the control of alumina concentration in aluminum reduction cells

    Directory of Open Access Journals (Sweden)

    Jens G. Balchen


    Full Text Available The paper presents a new method for the control of the concentration of the alumina in electrolysis cells for the production of aluminium. The method is based upon the well known fact that apparent resistivity of the cell is a function of the alumina concentration so that the resistivity has the lowest value around the concentration of three per cent and increases in both directions. The method uses the cross correlation between a perturbation of the feed flow of alumina into the cell and the resulting response in measured voltage across the cell. The cross-correlation is proportional to the slope of the resistivity against concentration curve, making it possible to control the alumina flow, to achieve a desired slope. The method has much in common with other methods presently in use which require a much more complicated computation scheme.

  11. Comparison of three MHD flow control methods for self-cooled liquid metal blankets

    Energy Technology Data Exchange (ETDEWEB)

    Walker, J.S.; Picologlou, B.F.


    The heat deposition in a blanket is concentrated near the first wall. Uniform liquid-metal velocity in a self-cooled blanket is unattractive, because it leads to low mixed-mean temperature rise through the blanket and reduced power conversion efficiency. The objective of MHD flow control is to use the electromagnetic forces to produce a non-uniform velocity distribution which gives a uniform temperature distribution over the thickness of the blanket. Three methods of MHD flow control are presented here and the MHD pressure drops corresponding to the three methods are compared. One of the methods, although successful at achieving nonuniform velocity profiles, permits a large circulation of electric current which produces a high pressure drop. The analytical results do not indicate a clear choice between the other two methods. The analytical results do point to possible difference in heat transfer performance with the two methods.

  12. Motility Control of Bacteria-Actuated Biodegradable Polymeric Microstructures by Selective Adhesion Methods

    Directory of Open Access Journals (Sweden)

    Hyung Jung Yoo


    Full Text Available Certain bacteria have motility and can be made non-toxic, and using them for drug delivery has been proposed. For example, using bacteria with flagella motion in multiple spin actuators in drug delivery microrobots has been suggested. This paper investigates various adhesion enhancement methods for attaching bacteria on preferred surfaces of cubic polymeric microstructures to achieve the directional control of motion. Serratia marcescens which has an excellent swimming behavior and 50-μm sized cubic structures made of biodegradable poly-capro-lactone (PCL are used. Three treatment methods are investigated and compared to the untreated control case. The first method is retarding bacterial attachments by coating certain surfaces with bovine serum albumin (BSA which makes those surfaces anti-adherent to bacteria. The second and third methods are roughening the surfaces with X-ray irradiation and plasma respectively to purposely increase bacterial attachments on the roughened surfaces. The measured motilities of bacteria-tethered PCL microactuators are 1.40 μm/s for the BSA coating method, 0.82 μm/s for the X-ray irradiation, and 3.89 μm/s for the plasma treatment method. Therefore, among the methods investigated in the paper the plasma treatment method achieves the highest directionality control of bacteria motility.

  13. Temporal parameter change of human postural control ability during upright swing using recursive least square method (United States)

    Goto, Akifumi; Ishida, Mizuri; Sagawa, Koichi


    The purpose of this study is to derive quantitative assessment indicators of the human postural control ability. An inverted pendulum is applied to standing human body and is controlled by ankle joint torque according to PD control method in sagittal plane. Torque control parameters (KP: proportional gain, KD: derivative gain) and pole placements of postural control system are estimated with time from inclination angle variation using fixed trace method as recursive least square method. Eight young healthy volunteers are participated in the experiment, in which volunteers are asked to incline forward as far as and as fast as possible 10 times over 10 [s] stationary intervals with their neck joint, hip joint and knee joint fixed, and then return to initial upright posture. The inclination angle is measured by an optical motion capture system. Three conditions are introduced to simulate unstable standing posture; 1) eyes-opened posture for healthy condition, 2) eyes-closed posture for visual impaired and 3) one-legged posture for lower-extremity muscle weakness. The estimated parameters Kp, KD and pole placements are applied to multiple comparison test among all stability conditions. The test results indicate that Kp, KD and real pole reflect effect of lower-extremity muscle weakness and KD also represents effect of visual impairment. It is suggested that the proposed method is valid for quantitative assessment of standing postural control ability.

  14. The Method of a Standalone Functional Verifying Operability of Sonar Control Systems

    Directory of Open Access Journals (Sweden)

    A. A. Sotnikov


    Full Text Available This article describes a method of standalone verifying sonar control system, which is based on functional checking of control system operability.The main features of realized method are a development of the valid mathematic model for simulation of sonar signals at the point of hydroacoustic antenna, a valid representation of the sonar control system modes as a discrete Markov model, providing functional object verification in real time mode.Some ways are proposed to control computational complexity in case of insufficient computing resources of the simulation equipment, namely the way of model functionality reduction and the way of adequacy reduction.Experiments were made using testing equipment, which was developed by department of Research Institute of Information Control System at Bauman Moscow State Technical University to verify technical validity of industrial sonar complexes.On-board software was artificially changed to create malfunctions in functionality of sonar control systems during the verifying process in order to estimate verifying system performances.The method efficiency was proved by the theory and experiment results in comparison with the basic methodology of verifying technical systems.This method could be also used in debugging of on-board software of sonar complexes and in development of new promising algorithms of sonar signal processing.

  15. Position Control Method For Pick And Place Robot Arm For Object Sorting System

    Directory of Open Access Journals (Sweden)

    Khin Moe Myint


    Full Text Available The more increase the number of industries in developing countries the more require labourers or workers in that. To reduce the cost of labour force and to increase the manufacturing capacity of industries the advanced robot arms are more needed. The aim of this journal is to eliminate the manual control for object sorting system.Robot arm design in this research uses two joints three links and servo motors to drive. Microcontroller is used to generate required PWM signal for servo motors. In this research the position control of robot arm was designed by using kinematic control methods. There are two types of kinematic control methods which are forward and reverse kinematic methods. In forward kinematic method the input parameters are the joint angles and link length of robot arm and then the output is the position at XYZ coordinate of tool or gripper. In inverse kinematic the input parameters are position at XYZ coordinate of gripper and the link length of robot arm and then the output parameters are the joint angles. So kinematic methods can explain the analytical description of the geometry motion of the manipulator with reference to a robot coordinate system fixed to a frame without consideration of the forces or the moments causing the movements. For sorting system Metal detector is used to detect the metal or non-metal. This position control of pick and place robot arm is fully tested and the result is obtained more precisely.

  16. A new compound control method for sine-on-random mixed vibration test (United States)

    Zhang, Buyun; Wang, Ruochen; Zeng, Falin


    Vibration environmental test (VET) is one of the important and effective methods to provide supports for the strength design, reliability and durability test of mechanical products. A new separation control strategy was proposed to apply in multiple-input multiple-output (MIMO) sine on random (SOR) mixed mode vibration test, which is the advanced and intensive test type of VET. As the key problem of the strategy, correlation integral method was applied to separate the mixed signals which included random and sinusoidal components. The feedback control formula of MIMO linear random vibration system was systematically deduced in frequency domain, and Jacobi control algorithm was proposed in view of the elements, such as self-spectrum, coherence, and phase of power spectral density (PSD) matrix. Based on the excessive correction of excitation in sine vibration test, compression factor was introduced to reduce the excitation correction, avoiding the destruction to vibration table or other devices. The two methods were synthesized to be applied in MIMO SOR vibration test system. In the final, verification test system with the vibration of a cantilever beam as the control object was established to verify the reliability and effectiveness of the methods proposed in the paper. The test results show that the exceeding values can be controlled in the tolerance range of references accurately, and the method can supply theory and application supports for mechanical engineering.

  17. Control Method Stretches Suspensions by Measuring the Sag of Strands in Cable-Stayed Bridges (United States)

    Bętkowski, Piotr


    In the article is described the method that allows on evaluation and validation of measurement correctness of dynamometers (strain gauges, tension meters) used in systems of suspensions. Control of monitoring devices such as dynamometers is recommended in inspections of suspension bridges. Control device (dynamometer) works with an anchor, and the degree of this cooperation could have a decisive impact on the correctness of the results. Method, which determines the stress in the strand (cable), depending on the sag of stayed cable, is described. This method can be used to control the accuracy of measuring devices directly on the bridge. By measuring the strand sag, it is possible to obtain information about the strength (force) which occurred in the suspension cable. Digital camera is used for the measurement of cable sag. Control measurement should be made independently from the controlled parameter but should verify this parameter directly (it is the best situation). In many cases in practice the controlled parameter is not designation by direct measurement, but the calculations, i.e. relation measured others parameters, as in the method described in the article. In such cases occurred the problem of overlapping error of measurement of intermediate parameters (data) and the evaluation of the reliability of the results. Method of control calculations made in relation to installed in the bridge measuring devices is doubtful without procedure of uncertainty estimation. Such an assessment of the accuracy can be performed using the interval numbers. With the interval numbers are possible the analysis of parametric relationship accuracy of the designation of individual parameters and uncertainty of results. Method of measurements, relations and analytical formulas, and numerical example can be found in the text of the article.

  18. Preparation of Controlled-Release Fine Particles Using a Dry Coating Method. (United States)

    Nakamura, Shohei; Sakamoto, Takatoshi; Ito, Tomonori; Kabasawa, Kazuhiro; Yuasa, Hiroshi


    Wet coating methods use organic solvents to prepare layered particles that provide controlled-release medications. However, this approach has disadvantages in that it can cause particle agglomeration, reduce pharmaceutical stability, and leave residual organic solvents. We used a dry coating method to overcome these issues. Fine particles (less than 50 μm in diameter) of controlled-release theophylline were created using theophylline (TP; model drug), polyethylene glycol 20,000 (PEG; drug fixative), hydrogenated castor oil (HCO; controlled-release material), hydrogenated rapeseed oil (HRSO; controlled-release material), and cornstarch (CS; core particle). An ultrahigh-speed mixer was employed to mix TP and CS for 5 min at 28,000 rpm. Subsequent addition of PEG produced single-core particles with a drug reservoir coating. Addition of HCO and HRSO to these particles produced a controlled-release layer on their surface, resulting in less than 10% TP dissolution after 8 h. We successfully demonstrated that this dry coating method could be used to coat 16-μm CS particles with a drug reservoir layer and a controlled-release layer, producing multi-layer coated single-core particles that were less than 50 μm in diameter. These can be used to prepare controlled-release tablets, capsules, and orally disintegrating tablets.

  19. Explicit Singly Diagonally Implicit Runge-Kutta Methods and Adaptive Stepsize Control for Reservoir Simulation

    DEFF Research Database (Denmark)

    Völcker, Carsten; Jørgensen, John Bagterp; Thomsen, Per Grove


    The implicit Euler method, normally refered to as the fully implicit (FIM) method, and the implicit pressure explicit saturation (IMPES) method are the traditional choices for temporal discretization in reservoir simulation. The FIM method offers unconditionally stability in the sense of discrete....... Current reservoir simulators apply timestepping algorithms that are based on safeguarded heuristics, and can neither guarantee convergence in the underlying equation solver, nor provide estimates of the relations between convergence, integration error and stepsizes. We establish predictive stepsize...... control applied to high order methods for temporal discretization in reservoir simulation. The family of Runge-Kutta methods is presented and in particular the explicit singly diagonally implicit Runge-Kutta (ESDIRK) method with an embedded error estimate is described. A predictive stepsize adjustment...

  20. Method and apparatus for smart battery charging including a plurality of controllers each monitoring input variables (United States)

    Hammerstrom, Donald J.


    A method for managing the charging and discharging of batteries wherein at least one battery is connected to a battery charger, the battery charger is connected to a power supply. A plurality of controllers in communication with one and another are provided, each of the controllers monitoring a subset of input variables. A set of charging constraints may then generated for each controller as a function of the subset of input variables. A set of objectives for each controller may also be generated. A preferred charge rate for each controller is generated as a function of either the set of objectives, the charging constraints, or both, using an algorithm that accounts for each of the preferred charge rates for each of the controllers and/or that does not violate any of the charging constraints. A current flow between the battery and the battery charger is then provided at the actual charge rate.