WorldWideScience

Sample records for monthly compensation base

  1. 76 FR 70515 - 2012 Railroad Experience Rating Proclamations, Monthly Compensation Base and Other Determinations

    Science.gov (United States)

    2011-11-14

    ... monthly compensation base. Under section 1(k), remuneration earned from employment covered under the Act cannot be considered subsidiary remuneration if the employee's base year compensation is less than 2.5... an employee's base year compensation, any money remuneration in a month not in excess of an...

  2. 75 FR 69146 - 2011 Railroad Experience Rating Proclamations, Monthly Compensation Base and Other Determinations

    Science.gov (United States)

    2010-11-10

    ... monthly compensation base. Under section 1(k), remuneration earned from employment covered under the Act cannot be considered subsidiary remuneration if the employee's base year compensation is less than 2.5... base year compensation, any money remuneration in a month not in excess of an amount that bears...

  3. 77 FR 66876 - 2013 Railroad Experience Rating Proclamations, Monthly Compensation Base and Other Determinations

    Science.gov (United States)

    2012-11-07

    ... amounts related to the monthly compensation base. Under section 1(k), remuneration earned from employment covered under the Act cannot be considered subsidiary remuneration if the employee's base year... compensation in the base year. In determining an employee's base year compensation, any money remuneration in...

  4. 78 FR 69141 - 2014 Railroad Experience Rating Proclamations, Monthly Compensation Base and Other Determinations

    Science.gov (United States)

    2013-11-18

    ... 2014 Railroad Experience Rating Proclamations, Monthly Compensation Base and Other Determinations... experience-based employer contribution rates for the following year. The RRB is further required by section 8... under the Act cannot be considered subsidiary remuneration if the employee's base year compensation...

  5. 20 CFR 226.63 - Determining monthly compensation.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Determining monthly compensation. 226.63... COMPUTING EMPLOYEE, SPOUSE, AND DIVORCED SPOUSE ANNUITIES Years of Service and Average Monthly Compensation § 226.63 Determining monthly compensation. (a) Based on yearly compensation. If Board records do...

  6. 20 CFR 226.62 - Computing average monthly compensation.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Computing average monthly compensation. 226... Compensation § 226.62 Computing average monthly compensation. The employee's average monthly compensation is computed by first determining the employee's highest 60 months of railroad compensation...

  7. 38 CFR 3.351 - Special monthly dependency and indemnity compensation, death compensation, pension and spouse's...

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Special monthly dependency and indemnity compensation, death compensation, pension and spouse's compensation ratings. 3.351 Section 3.351 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Pension...

  8. Formula Based Compensation.

    Science.gov (United States)

    Sears, Doug; Picus, Lawrence O.

    1999-01-01

    Recognizing that traditional salary bargaining is divisive and that teacher salaries should remain competitive, Temple City (California) Unified School District has been experimenting with formula-based compensation for the past four years. Primary benefits are lack of conflict over salary increases, which are determined before negotiating other…

  9. 38 CFR 17.151 - Invalid lifts for recipients of aid and attendance allowance or special monthly compensation.

    Science.gov (United States)

    2010-07-01

    ...) under the provisions of 38 U.S.C. 1114(r), or (2) comparable compensation benefits at the rates... greater compensation benefit rather than aid and attendance pension to which he or she has been... recipients of aid and attendance allowance or special monthly compensation. 17.151 Section 17.151 Pensions...

  10. PMD compensation based on a new type dynamic first-order PMD compensator

    Institute of Scientific and Technical Information of China (English)

    Jiajun Wang; Shilong Pan; Jia Jia; Yanfu Yang; Caiyun Lou

    2006-01-01

    @@ A dynamic first-order polarization mode dispersion (PMD) compensator based on garnet and yttrium vanadate crystal has been proposed and implemented. Consisting of a differential group delay (DGD) generator and a Faraday rotator (FR), this PMD compensator has only two degrees of freedom. Feedback control and compensation algorithm are both very simple. Experimental results reveal the compensator behaviors to be excellent for PMD compensation in 40-Gb/s optical time domain multiplexing (OTDM)system.

  11. 20 CFR 336.4 - Base year compensation.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Base year compensation. 336.4 Section 336.4... DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.4 Base year compensation. (a) Formula. For the purposes of this part, an employee's base year compensation includes any compensation in excess...

  12. Illumination compensation in ground based hyperspectral imaging

    Science.gov (United States)

    Wendel, Alexander; Underwood, James

    2017-07-01

    Hyperspectral imaging has emerged as an important tool for analysing vegetation data in agricultural applications. Recently, low altitude and ground based hyperspectral imaging solutions have come to the fore, providing very high resolution data for mapping and studying large areas of crops in detail. However, these platforms introduce a unique set of challenges that need to be overcome to ensure consistent, accurate and timely acquisition of data. One particular problem is dealing with changes in environmental illumination while operating with natural light under cloud cover, which can have considerable effects on spectral shape. In the past this has been commonly achieved by imaging known reference targets at the time of data acquisition, direct measurement of irradiance, or atmospheric modelling. While capturing a reference panel continuously or very frequently allows accurate compensation for illumination changes, this is often not practical with ground based platforms, and impossible in aerial applications. This paper examines the use of an autonomous unmanned ground vehicle (UGV) to gather high resolution hyperspectral imaging data of crops under natural illumination. A process of illumination compensation is performed to extract the inherent reflectance properties of the crops, despite variable illumination. This work adapts a previously developed subspace model approach to reflectance and illumination recovery. Though tested on a ground vehicle in this paper, it is applicable to low altitude unmanned aerial hyperspectral imagery also. The method uses occasional observations of reference panel training data from within the same or other datasets, which enables a practical field protocol that minimises in-field manual labour. This paper tests the new approach, comparing it against traditional methods. Several illumination compensation protocols for high volume ground based data collection are presented based on the results. The findings in this paper are

  13. The Pros and Cons of Performance-Based Compensation.

    Science.gov (United States)

    Solmon, Lewis C.; Podgursky, Michael

    This paper analyzes the current and historical criticism of performance-based compensation in K-12 education. It claims that new compensation methods are feasible and are necessary in order to attract and retain the best and the brightest into the teaching profession. The document outlines the objections to performance-based compensation, which in…

  14. Disclosed Values of Option-Based Compensation

    DEFF Research Database (Denmark)

    Bechmann, Ken L.; Hjortshøj, Toke Lilhauge

    New accounting standards require firms to expense the costs of option-based compensation (OBC), but the associated valuations offer many challenges for firms. Earlier research has documented that firms in the U.S. generally underreport the values of OBC by manipulating the inputs used for valuation......-Scholes parameters in their valuations. Furthermore, firms determine the expected time to maturity in a way that is generally consistent with the guidelines provided by the new accounting standards. The findings differ from those of the U.S., but is consistent with the more limited use of OBC and the lower level...

  15. Dispersion compensation based on prism compressor

    Science.gov (United States)

    Liu, Hongying; Lan, Tian; Chen, Xiaomei; Ni, Guoqiang

    2017-04-01

    A prism compressor can compensate dispersion of femtosecond light pulses travelling in air for laser ranging. An accurate expression of the group delay dispersion (GDD) of a prism compressor at arbitrary incident angle and at arbitrary incident point is obtained, which is of benefit to finely compensating dispersion of femtosecond pulses. Influences of several parameters on group delay dispersion are analyzed for the active compensation of dispersion of femtosecond pulses. These expressions are convenient to applications of intra- and extra-cavity dispersion compensation of ultra-short laser pulses, as well as fine compensation of satellite laser ranging and laser altimetry.

  16. Transitioning to value-based physician compensation.

    Science.gov (United States)

    Epstein, Johanna

    2014-12-01

    An effective strategy for creating a viable physician compensation plan should include nine key steps or tactics: Get physicians on board early. Engage a physician champion. Create a compensation committee. Address department-level issues and differences. Verify the plan's affordability. Adopt a routine review schedule. Understand the payer environment and keep in contact with payers. Stay abreast of industry trends. Maintain an ongoing dialogue with physicians.

  17. Re-planning for compensator-based IMRT with original compensators.

    Science.gov (United States)

    Zhang, Geoffrey; Feygelman, Vladimir; Stevens, Craig; Li, Weiqi; Leuthold, Susan; Springett, Gregory; Hoffe, Sarah

    2011-01-01

    Compared with multileaf collimator (MLC)-based intensity-modulated radiotherapy (IMRT) for moving targets, compensator-based IMRT has advantages such as shorter beam-on time, fewer monitor units with potentially decreased secondary carcinogenesis risk, better optimization-to-deliverable dose conversion, and often better dose conformity. Some of the disadvantages include additional time for the compensators to be built and delivered, as well as extra cost. Patients undergoing treatment of abdominal cancers often experience weight loss. It would be necessary to account for this change in weight with a new plan and a second set of compensators. However, this would result in treatment delays and added costs. We have developed a method to re-plan the patient using the same set of compensators. Because the weight changes seen with the treatment of abdominal cancers are usually relatively small, a new 4D computed tomography (CT) acquired in the treatment position with markers on the original isocenter tattoos can be registered to the original planning scan. The contours of target volumes from the original scans are copied to the new scan after fusion. The original compensator set can be used together with a few field-in-field (FiF) beams defined by the MLC (or beams with cerrobend blocks for accelerators not equipped with a MLC). The weights of the beams with compensators are reduced so that the FiF or blocked beams can be optimized to mirror the original plan and dose distribution. Seven abdominal cancer cases are presented using this technique. The new plan on the new planning CT images usually has the same dosimetric quality as the original. The target coverage and dose uniformity are improved compared with the plan without FiF/block modification. Techniques combining additional FiF or blocked beams with the original compensators optimize the treatment plans when patients lose weight and save time and cost compared with generating plans with a new set of compensators.

  18. Stock-based compensation plans and employee incentives

    OpenAIRE

    Zabojnik, Jan

    2014-01-01

    Standard principal-agent theory predicts that large firms should not use employee stock options and other stock-based compensation to provide incentives to non-executive employees. Yet, business practitioners appear to believe that stock-based compensation improves incentives, and mounting empirical evidence points to the same conclusion. This paper provides an explanation for why stock-based incentives can be effective. In the model of this paper, employee stock options complement individual...

  19. Die Face Engineering based Springback Compensation Strategy and Implementation

    Science.gov (United States)

    Tang, Arthur; Lee, Wing; He, Jeanne; Xu, Jinbo; Liu, Kesu; Chen, Chin Chun

    2005-08-01

    Springback or shape change has been one of the major challenges in sheet metal fabrication, particularly with increase application of high strength steel (HSS) and aluminum alloys in automotive stamping. Springback, an elastic material recovery after the unloading of stamping tools, causes variations and inconsistencies of final part dimensions. Minor or mild springback usually can be corrected in the re-strike process. Excessive springback must be corrected so the part will be produced within the given design tolerance and dimension. The commonly used Spring Forward approaches and shape compensations such as over-crown and over-bending are proven effective to alleviate excessive springback. To enhance these approaches, a new strategy of Die Face Engineering (DFE) based processing is proposed to quickly and easily to achieve the maximum allowable compensation using the under cut (or die lock) as the primary criteria. The implementation of the die face compensation through iterative FEA calculation, automatic surface mapping, projection and manual morphing are crucial to meet production environment requirements in terms of generating NC quality CAD surfaces of the compensated or morphed die face. In this paper, the strategy of the die face compensation with the consideration of the under cut criteria is presented. The implementation of various processes to enable user to perform the die face compensation task in a production environment is also discussed. Finally, two examples are shown to demonstrate the implementation of the proposed springback compensation scheme based on the combined CAE/CAD methodology.

  20. ROBOT'S MOTION ERROR AND ONLINE COMPENSATION BASED ON FORCE SENSOR

    Institute of Scientific and Technical Information of China (English)

    GAN Fangjian; LIU Zhengshi; REN Chuansheng; ZHANG Ping

    2007-01-01

    Robot's dynamic motion error and on-line compensation based on multi-axis force sensor are dealt with. It is revealed that the reasons of the error are formed and the relations of the error are delivered. A motion equation of robot's termination with the error is established, and then, an error matrix and an error compensation matrix of the motion equation are also defined. An on-line error's compensation method is put forward to decrease the displacement error, which is a degree of millimeter, shown by the result of Simulation of PUMA562 robot.

  1. ONLINE GRINDING WHEEL WEAR COMPENSATION BY IMAGE BASED MEASURING TECHNIQUES

    Institute of Scientific and Technical Information of China (English)

    WAN Daping; HU Dejin; WU Qi; ZHANG Yonghong

    2006-01-01

    Automatic compensation of grinding wheel wear in dry grinding is accomplished by an image based online measurement method. A kind of PC-based charge-coupled device image recognition system is schemed out, which detects the topography changes of the grinding wheel surface. Profile data, which corresponds to the wear and the topography, is measured by using a digital image processing method. The grinding wheel wear is evaluated by analyzing the position deviation of the grinding wheel edge. The online wear compensation is achieved according to the measure results. The precise detection and automatic compensation system is integrated into an open structure CNC curve grinding machine. A practical application is carried out to fulfil the precision curve grinding. The experimental results confirm the benefits of the proposed techniques, and the online detection accuracy is less than 5 μm. The grinding machine provides higher precision according to the in-process grinding wheel error compensation.

  2. Stochastic Wheel-Slip Compensation Based Robot Localization and Mapping

    Directory of Open Access Journals (Sweden)

    SIDHARTHAN, R. K.

    2016-05-01

    Full Text Available Wheel slip compensation is vital for building accurate and reliable dead reckoning based robot localization and mapping algorithms. This investigation presents stochastic slip compensation scheme for robot localization and mapping. Main idea of the slip compensation technique is to use wheel-slip data obtained from experiments to model the variations in slip velocity as Gaussian distributions. This leads to a family of models that are switched depending on the input command. To obtain the wheel-slip measurements, experiments are conducted on a wheeled mobile robot and the measurements thus obtained are used to build the Gaussian models. Then the localization and mapping algorithm is tested on an experimental terrain and a new metric called the map spread factor is used to evaluate the ability of the slip compensation technique. Our results clearly indicate that the proposed methodology improves the accuracy by 72.55% for rotation and 66.67% for translation motion as against an uncompensated mapping system. The proposed compensation technique eliminates the need for extro receptive sensors for slip compensation, complex feature extraction and association algorithms. As a result, we obtain a simple slip compensation scheme for localization and mapping.

  3. Marine Ecological Environment Management Based on Ecological Compensation Mechanisms

    Directory of Open Access Journals (Sweden)

    Qunzhen Qu

    2016-12-01

    Full Text Available The level of marine environmental management is a key factor in the successful implementation of marine power strategies. The improvement in management levels of marine environments requires innovation in marine management. In other words, the transformation of marine environmental management into marine ecological environment management must be done in order to achieve sustainable development of the marine economy. As an environmental economic policy that combines both administrative and market measures, ecological compensation mechanisms have significant advantages in marine ecological environment management. Based on the study of the current development of ecological compensation mechanisms in China, through the analysis of the connotation of marine ecological civilization, existing marine ecological protection practices and marine environmental management methods, this paper posits that the current marine ecological environment management in China should be established on the basis of ecological compensation mechanisms. At present, a lack of laws and regulations for overall marine ecological environment management is the key factor restricting the practice of marine ecological environment management. Therefore, it is necessary to explore the current path of marine ecological environment management in China from the perspective of the construction of legal system of ecological compensation law, the establishment of ecological compensation fees, ecological taxes and ecological compensation fund systems, and the clear status for a marine ecological management and supervision body.

  4. Study on Compensation Control of STATCOM Based on MMC

    Directory of Open Access Journals (Sweden)

    Xie Yan

    2016-01-01

    Full Text Available This paper introduced modular multi-level converter (MMC, which could enhance the voltage and power level by sub-converter modules in series and was easy to extend to any level of output. Its structure and working mechanism were described. By analyzing the energy transfer performance of STATCOM based on MMC working conditions in the compensation, a comprehensive compensation control strategy was proposed based on direct current control mode. By analyzing the higher harmonic components circulation generated by the inconsistencies in the three-phase upper and lower arm voltage, a loop control strategy is proposed for the suppression of the circulation in the arms of the M-STATCOM. The simulation results show the strategy has a better tracking precision and response speed for the compensation control.

  5. Signal based motion compensation for synthetic aperture radar

    Energy Technology Data Exchange (ETDEWEB)

    John Kirk

    1999-06-07

    The purpose of the Signal Based Motion Compensation (SBMC) for Synthetic Aperture Radar (SAR) effort is to develop a method to measure and compensate for both down range and cross range motion of the radar in order to provide high quality focused SAR imagery in the absence of precision measurements of the platform motion. Currently SAR systems require very precise navigation sensors for motion compensation. These sensors are very expensive and are often supplied in pairs for reliability. In the case of GPS they can be jammed, further degrading performance. This makes for a potentially very expensive and possibly vulnerable SAR system. SBMC can eliminate or reduce the need for these expensive navigation sensors thus reducing the cost of budget minded SAR systems. The results on this program demonstrated the capability of the SBMC approach.

  6. Whispered speaker identification based on feature and model hybrid compensation

    Institute of Scientific and Technical Information of China (English)

    GU Xiaojiang; ZHAO Heming; Lu Gang

    2012-01-01

    In order to increase short time whispered speaker recognition rate in variable chan- nel conditions, the hybrid compensation in model and feature domains was proposed. This method is based on joint factor analysis in training model stage. It extracts speaker factor and eliminates channel factor by estimating training speech speaker and channel spaces. Then in the test stage, the test speech channel factor is projected into feature space to engage in feature compensation, so it can remove channel information both in model and feature domains in order to improve recognition rate. The experiment result shows that the hybrid compensation can obtain the similar recognition rate in the three different training channel conditions and this method is more effective than joint factor analysis in the test of short whispered speech.

  7. Design of GEO helix tourist orbit based on perturbation compensation

    Science.gov (United States)

    Xu, Yanli; Zhou, Haijun; Dai, Huayu

    2017-05-01

    Constrained by country area and technology level, GEO target and environment's detection become practical difficulty which restrict development of our country's space technology. Helix tourist orbit is introduced; orbit formation effect from perturbation of nonsphericfigure of the Earth, the solar and lunar attraction is analyzed; orbit design method based on perturbation compensation is put forward.

  8. Performance-Based Compensation: Focus on Special Education Teachers. inForum

    Science.gov (United States)

    Burdette, Paula

    2011-01-01

    The purpose of this document is to describe states' work in the area of performance-based compensation with a focus on special educators, including how teacher evaluation informs compensation decisions, support given to local education agencies (LEAs), variables used to make compensation decisions and how performance-based compensation is funded.…

  9. A Novel Control algorithm based DSTATCOM for Load Compensation

    Science.gov (United States)

    R, Sreejith; Pindoriya, Naran M.; Srinivasan, Babji

    2015-11-01

    Distribution Static Compensator (DSTATCOM) has been used as a custom power device for voltage regulation and load compensation in the distribution system. Controlling the switching angle has been the biggest challenge in DSTATCOM. Till date, Proportional Integral (PI) controller is widely used in practice for load compensation due to its simplicity and ability. However, PI Controller fails to perform satisfactorily under parameters variations, nonlinearities, etc. making it very challenging to arrive at best/optimal tuning values for different operating conditions. Fuzzy logic and neural network based controllers require extensive training and perform better under limited perturbations. Model predictive control (MPC) is a powerful control strategy, used in the petrochemical industry and its application has been spread to different fields. MPC can handle various constraints, incorporate system nonlinearities and utilizes the multivariate/univariate model information to provide an optimal control strategy. Though it finds its application extensively in chemical engineering, its utility in power systems is limited due to the high computational effort which is incompatible with the high sampling frequency in these systems. In this paper, we propose a DSTATCOM based on Finite Control Set Model Predictive Control (FCS-MPC) with Instantaneous Symmetrical Component Theory (ISCT) based reference current extraction is proposed for load compensation and Unity Power Factor (UPF) action in current control mode. The proposed controller performance is evaluated for a 3 phase, 3 wire, 415 V, 50 Hz distribution system in MATLAB Simulink which demonstrates its applicability in real life situations.

  10. Force-compensated hydrogel-based pH sensor

    Science.gov (United States)

    Deng, Kangfa; Gerlach, Gerald; Guenther, Margarita

    2015-04-01

    This paper presents the design, simulation, assembly and testing of a force-compensated hydrogel-based pH sensor. In the conventional deflection method, a piezoresistive pressure sensor is used as a chemical-mechanical-electronic transducer to measure the volume change of a pH-sensitive hydrogel. In this compensation method, the pH-sensitive hydrogel keeps its volume constant during the whole measuring process, independent of applied pH value. In order to maintain a balanced state, an additional thermal actuator is integrated into the close-loop sensor system with higher precision and faster dynamic response. Poly (N-isopropylacrylamide) (PNIPAAm) with 5 mol% monomer 3-acrylamido propionic acid (AAmPA) is used as the temperature-sensitive hydrogel, while poly (vinyl alcohol) with poly (acrylic acid) (PAA) serves as the pH-sensitive hydrogel. A thermal simulation is introduced to assess the temperature distribution of the whole microsystem, especially the temperature influence on both hydrogels. Following tests are detailed to verify the working functions of a sensor based on pH-sensitive hydrogel and an actuator based on temperature-sensitive hydrogel. A miniaturized prototype is assembled and investigated in deionized water: the response time amounts to about 25 min, just half of that one of a sensor based on the conventional deflection method. The results confirm the applicability of t he compensation method to the hydrogel-based sensors.

  11. GRID VOLTAGE STABILITY ENHANCEMENT USING PHOTOVOLTAIC BASED STATIC SYNCHRONOUS COMPENSATOR

    Directory of Open Access Journals (Sweden)

    Arun Bhaskar Mayilvaganan

    2013-01-01

    Full Text Available Today, we are mostly dependent on non renewable energy that have been and will continue to be a major cause of pollution and other environmental degradation. Because of these problems and our dwindling supply of petroleum, finding sustainable alternatives is becoming increasingly urgent. Perhaps, the greatest challenge is in devising a sustainable future, which relies on integration and control of renewable energy sources in grid distributed generation. This study presents the usage of utilizing Photovoltaic (PV Solar Farm (SF during idle conditions as Static Synchronous Compensator (STATCOM, to regulate the point of common coupling voltage when the wind farm supply the power to the grid. The proposed control will enable increased connections of WECS to the grid. MATLAB/Simulink based simulation results are presented for validation of the system. The PV-STATCOM increase the stability of the grid with interconnected wind farm system without any use of additional compensator.

  12. A compensated fission detector based on photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Petit, M. [CEA/DAM Ile-de-France, DPTA/Service de Physique Nucleaire, BP 12, 91680 Bruyeres-le-Chatel (France); Ethvignot, T. [CEA/DAM Ile-de-France, DPTA/Service de Physique Nucleaire, BP 12, 91680 Bruyeres-le-Chatel (France); Granier, T. [CEA/DAM Ile-de-France, DPTA/Service de Physique Nucleaire, BP 12, 91680 Bruyeres-le-Chatel (France)]. E-mail: thierry.granier@cea.fr; Haight, R.C. [LANSCE-3, Los Alamos National Laboratory, MS H855, Los Alamos, NM 87545 (United States); O' Donnell, J.M. [LANSCE-3, Los Alamos National Laboratory, MS H855, Los Alamos, NM 87545 (United States); Rochman, D. [LANSCE-3, Los Alamos National Laboratory, MS H855, Los Alamos, NM 87545 (United States); Wender, S.A. [LANSCE-3, Los Alamos National Laboratory, MS H855, Los Alamos, NM 87545 (United States); Bond, E.M. [C-INC, Los Alamos National Laboratory, MS J514, Los Alamos, NM 87545 (United States); Bredeweg, T.A. [C-INC, Los Alamos National Laboratory, MS J514, Los Alamos, NM 87545 (United States); Vieira, D.J. [C-INC, Los Alamos National Laboratory, MS J514, Los Alamos, NM 87545 (United States); Wilhelmy, J.B. [C-INC, Los Alamos National Laboratory, MS J514, Los Alamos, NM 87545 (United States); Danon, Y. [Rensselaer Polytechnic Institute, Troy, NY 12180 (United States)

    2005-12-01

    Standard techniques of event-by-event detection of fission may fail when operated in high {gamma}-ray or particle radiation environments. This is the case within the 800MeV proton-driven lead slowing-down neutron spectrometer at LANSCE where standard fission detectors are found to be inoperable for microseconds to milliseconds after each proton pulse. To overcome this problem, a simple fission fragment detector based on compensated photovoltaic cells has been developed. The compensated detector has lower susceptibility to the strong {gamma}-flash and can recover much faster than an uncompensated detector. This detector is well adapted to applications involving the detection of fission in regions where high intensity {gamma}-ray and/or particle radiation fields exist.

  13. A compensated fission detector based on photovoltaic cells

    Science.gov (United States)

    Petit, M.; Ethvignot, T.; Granier, T.; Haight, R. C.; O'Donnell, J. M.; Rochman, D.; Wender, S. A.; Bond, E. M.; Bredeweg, T. A.; Vieira, D. J.; Wilhelmy, J. B.; Danon, Y.

    2005-12-01

    Standard techniques of event-by-event detection of fission may fail when operated in high γ-ray or particle radiation environments. This is the case within the 800 MeV proton-driven lead slowing-down neutron spectrometer at LANSCE where standard fission detectors are found to be inoperable for microseconds to milliseconds after each proton pulse. To overcome this problem, a simple fission fragment detector based on compensated photovoltaic cells has been developed. The compensated detector has lower susceptibility to the strong γ-flash and can recover much faster than an uncompensated detector. This detector is well adapted to applications involving the detection of fission in regions where high intensity γ-ray and/or particle radiation fields exist.

  14. Controlling chaos based on an adaptive nonlinear compensator mechanism

    Institute of Scientific and Technical Information of China (English)

    Tian Ling-Ling; Li Dong-Hai; Sun Xian-Fang

    2008-01-01

    The control problems of chaotic systems are investigated in the presence of parametric uncertainty and persistent external disturbances based on nonlinear control theory.By using a designed nonlinear compensator mechanism,the system deterministic nonlinearity,parametric uncertainty and disturbance effect can be compensated effectively.The renowned chaotic Lorenz system subjected to parametric variations and external disturbances is studied as an illustrative example.From the Lyapunov stability theory,sufficient conditions for choosing control parameters to guarantee chaos control are derived.Several experiments are carried out,including parameter change experiments,set-point change experiments and disturbance experiments.Simulation results indicate that the chaotic motion can be regulated not only to steady states but also to any desired periodic orbits with great immunity to parametric variations and external disturbances.

  15. Optimum Position of Polarizer-Based Compensator for Enhanced Tolerance to Polarization Mode Dispersion

    Institute of Scientific and Technical Information of China (English)

    Daniele; Alzetta; Masayuki; Matsumoto

    2003-01-01

    We show through numerical simulation that the performance of two types of polarization-mode dispersion polarizer-based compensation techniques may be improved by optimizing the position of the compensator along the transmission line.

  16. Index-based reactive power compensation scheme for voltage regulation

    Science.gov (United States)

    Dike, Damian Obioma

    2008-10-01

    Increasing demand for electrical power arising from deregulation and the restrictions posed to the construction of new transmission lines by environment, socioeconomic, and political issues had led to higher grid loading. Consequently, voltage instability has become a major concern, and reactive power support is vital to enhance transmission grid performance. Improved reactive power support to distressed grid is possible through the application of relatively unfamiliar emerging technologies of "Flexible AC Transmission Systems (FACTS)" devices and "Distributed Energy Resources (DERS)." In addition to these infrastructure issues, a lack of situational awareness by system operators can cause major power outages as evidenced by the August 14, 2003 widespread North American blackout. This and many other recent major outages have highlighted the inadequacies of existing power system indexes. In this work, a novel "Index-based reactive compensation scheme" appropriate for both on-line and off-line computation of grid status has been developed. A new voltage stability index (Ls-index) suitable for long transmission lines was developed, simulated, and compared to the existing two-machine modeled L-index. This showed the effect of long distance power wheeling amongst regional transmission organizations. The dissertation further provided models for index modulated voltage source converters (VSC) and index-based load flow analysis of both FACTS and microgrid interconnected power systems using the Newton-Raphson's load flow model incorporated with multi-FACTS devices. The developed package has been made user-friendly through the embodiment of interactive graphical user interface and implemented on the IEEE 14, 30, and 300 bus systems. The results showed reactive compensation has system wide-effect, provided readily accessible system status indicators, ensured seamless DERs interconnection through new islanding modes and enhanced VSC utilization. These outcomes may contribute

  17. Friction Effects on Inertia Compensators used for Heliostat Base Motion Isolation.

    Science.gov (United States)

    The base motion isolation of an optical beam deflector with a two-axis gimbal support ( heliostat ) is discussed. The use of an auxiliary inertia...coupled between the elevation gimbal and the heliostat mirror to produce a compensating torque referred to as a gear compensator and a belt compensator

  18. The Causes and Risk-Taking on the Change of CEO Equity-Based Compensation Structure

    OpenAIRE

    Yin-Hua Yeh; Zih-Heng Lai

    2014-01-01

    This paper explores to find out the determinants of the change of CEO equity-based compensation structure. We use the US nonfinancial listed companies as sample and find that when the change of stock return and size increase positively, the percentage of stock compensation and the stock-minus-option compensation relative to last year increase. Moreover, when the change of CEO duality increases positively, the percentage of stock-compensation and the percentage of stock-minus-option compensati...

  19. Multiple description video coding based on residuum compensation

    Institute of Scientific and Technical Information of China (English)

    ZHAO AnBang; YU Yun; SUN GuoCang; LI GuanFang; HUI JunYing

    2009-01-01

    As one of the focus areas of robust video coding and transmission, multiple description video coding has attracted comprehensive attention. The low coding efficiency of multiple description video coding is always the major challenge in this field. In order to improve the performance of multiple description video coding, this paper proposes a scheme based on residuum compensation. In this scheme, each original video frame is encoded with a traditional encoder first to get the first description. Then the error residuum of each coded frame is added up to the corresponding original frame and the resulting compensated frame is encoded by another traditional encoder to generate the second description successively. This work uses JM10.0 of H.264/AVC as video coding codec to conduct the experiments. The experimental results show that the proposed scheme has good coding performance. Compared to state of art traditional single description encoder, the efficiency can be as high as 90%, i.e. the redundancy Is only 10% to 20%.

  20. Multimodal MRI Neuroimaging with Motion Compensation Based on Particle Filtering

    CERN Document Server

    Chen, Yu-Hui; Kim, Boklye; Meyer, Charles; Hero, Alfred

    2015-01-01

    Head movement during scanning impedes activation detection in fMRI studies. Head motion in fMRI acquired using slice-based Echo Planar Imaging (EPI) can be estimated and compensated by aligning the images onto a reference volume through image registration. However, registering EPI images volume to volume fails to consider head motion between slices, which may lead to severely biased head motion estimates. Slice-to-volume registration can be used to estimate motion parameters for each slice by more accurately representing the image acquisition sequence. However, accurate slice to volume mapping is dependent on the information content of the slices: middle slices are information rich, while edge slides are information poor and more prone to distortion. In this work, we propose a Gaussian particle filter based head motion tracking algorithm to reduce the image misregistration errors. The algorithm uses a dynamic state space model of head motion with an observation equation that models continuous slice acquisitio...

  1. Dynamic Consensus Algorithm based Distributed Unbalance Compensation in Islanded Microgrids

    DEFF Research Database (Denmark)

    Meng, Lexuan; Zhao, Xin; Firoozabadi, Mehdi Savaghebi;

    2015-01-01

    In islanded microgrids (MG), distributed generators (DG) can be employed as distributed compensators for improving the power quality (voltage unbalance and harmonics) in consumer side. Hierarchical control is usually applied with different control levels differentiated. In case of voltage unbalance...... compensation, droop control and virtual impedance can be applied in primary control to help the positive sequence active and reactive power sharing. Secondary control is used to assist voltage unbalance compensation. However, if transmission line differences are considered, the negative sequence current cannot...

  2. Landmark-Based Drift Compensation Algorithm for Inertial Pedestrian Navigation

    Science.gov (United States)

    Munoz Diaz, Estefania; Caamano, Maria; Fuentes Sánchez, Francisco Javier

    2017-01-01

    The navigation of pedestrians based on inertial sensors, i.e., accelerometers and gyroscopes, has experienced a great growth over the last years. However, the noise of medium- and low-cost sensors causes a high error in the orientation estimation, particularly in the yaw angle. This error, called drift, is due to the bias of the z-axis gyroscope and other slow changing errors, such as temperature variations. We propose a seamless landmark-based drift compensation algorithm that only uses inertial measurements. The proposed algorithm adds a great value to the state of the art, because the vast majority of the drift elimination algorithms apply corrections to the estimated position, but not to the yaw angle estimation. Instead, the presented algorithm computes the drift value and uses it to prevent yaw errors and therefore position errors. In order to achieve this goal, a detector of landmarks, i.e., corners and stairs, and an association algorithm have been developed. The results of the experiments show that it is possible to reliably detect corners and stairs using only inertial measurements eliminating the need that the user takes any action, e.g., pressing a button. Associations between re-visited landmarks are successfully made taking into account the uncertainty of the position. After that, the drift is computed out of all associations and used during a post-processing stage to obtain a low-drifted yaw angle estimation, that leads to successfully drift compensated trajectories. The proposed algorithm has been tested with quasi-error-free turn rate measurements introducing known biases and with medium-cost gyroscopes in 3D indoor and outdoor scenarios. PMID:28671622

  3. Landmark-Based Drift Compensation Algorithm for Inertial Pedestrian Navigation.

    Science.gov (United States)

    Diaz, Estefania Munoz; Caamano, Maria; Sánchez, Francisco Javier Fuentes

    2017-07-03

    The navigation of pedestrians based on inertial sensors, i.e., accelerometers and gyroscopes, has experienced a great growth over the last years. However, the noise of medium- and low-cost sensors causes a high error in the orientation estimation, particularly in the yaw angle. This error, called drift, is due to the bias of the z-axis gyroscope and other slow changing errors, such as temperature variations. We propose a seamless landmark-based drift compensation algorithm that only uses inertial measurements. The proposed algorithm adds a great value to the state of the art, because the vast majority of the drift elimination algorithms apply corrections to the estimated position, but not to the yaw angle estimation. Instead, the presented algorithm computes the drift value and uses it to prevent yaw errors and therefore position errors. In order to achieve this goal, a detector of landmarks, i.e., corners and stairs, and an association algorithm have been developed. The results of the experiments show that it is possible to reliably detect corners and stairs using only inertial measurements eliminating the need that the user takes any action, e.g., pressing a button. Associations between re-visited landmarks are successfully made taking into account the uncertainty of the position. After that, the drift is computed out of all associations and used during a post-processing stage to obtain a low-drifted yaw angle estimation, that leads to successfully drift compensated trajectories. The proposed algorithm has been tested with quasi-error-free turn rate measurements introducing known biases and with medium-cost gyroscopes in 3D indoor and outdoor scenarios.

  4. Feature-based engineering of compensations in web service environment

    DEFF Research Database (Denmark)

    Schaefer, Michael; Dolog, Peter

    2009-01-01

    In this paper, we introduce a product line approach for developing Web services with extended compensation capabilities. We adopt a feature modelling approach in order to describe variable and common compensation properties of Web service variants, as well as service consumer application...

  5. CPLD-Based Circuit Design of IGBT Dead-Time Compensation

    Directory of Open Access Journals (Sweden)

    Qing-zhen WANG

    2015-05-01

    Full Text Available IGBT (insulated-gate bipolar transistors dead-time compensation circuit has a very important significant for improving the output voltage waveform of the inverter, reducing the harmonic output current. Thus, many compensation strategies are reported in literatures and have been implemented in industrial drives recently. Overall, the method of dead-time compensation can be divided into hardware compensation and software compensation. Hardware compensation method needs additional hardware circuits, which means additional space and cost. Still more, the additional circuit is easy to interfere with others, which can reduce the compensation accuracy. While the software compensation method takes up a lot of memory space and additional input-output ports of processor, which often result to the added operation and heat dissipation of controller. In this paper, CPLD (complex programmable logic device-based circuit design of dead-time compensation is presented to solve these existed drawbacks. It is verified that not only can the circuit simplify existed inverter dead-time compensation design, but also it has the advantages of small volume, strong anti-interference ability, and high compensation precision. The simulation results validate that this method is feasible and effective.

  6. Statistic Model Based Dynamic Channel Compensation for Telephony Speech Recognition

    Institute of Scientific and Technical Information of China (English)

    ZHANGHuayun; HANZhaobing; XUBo

    2004-01-01

    The degradation of speech recognition performance in real-life environments and through transmission channels is a main embarrassment for many speechbased applications around the world, especially when nonstationary noise and changing channel exist. Previous works have shown that the main reason for this performance degradation is the variational mismatch caused by different telephone channels between the testing and training sets. In this paper, we propose a statistic model based implementation to dynamically compensate this mismatch. Firstly, we focus on a Maximum-likelihood (ML) estimation algorithm for telephone channels. In experiments on Mandarin Large vocabulary continuous speech recognition (LVCSR) over telephone lines, the Character error rate (CER) decreases more than 20%. The average delay is about 300-400ms. Secondly, we will extend it by introducing a phone-conditioned prior statistic model for the channels and applying Maximum a posteriori (MAP) estimation technique. Compared to the ML based method, the MAP based algorithm follows with the variations within channels more effectively. Average delay of the algorithm is decreased to 200ms. An additional 7-8% CER relative reduction is observed in LVCSR.

  7. Flatness-based pre-compensation of laser diodes

    CERN Document Server

    Rouchon, A Abichou S Elasmi P

    2007-01-01

    A physical nonlinear dynamical model of a laser diode is considered. We propose a feed-forward control scheme based on differential flatness for the design of input-current modulations to compensate diode distortions. The goal is to transform without distortion a radio-frequency current modulation into a light modulation leaving the laser-diode and entering an optic fiber. We prove that standard physical dynamical models based on dynamical electron and photons balance are flat systems when the current is considered as control input, the flat output being the photon number (proportional to the light power). We prove that input-current is an affine map of the flat output, its logarithm and their time-derivatives up to order two. When the flat output is an almost harmonic signal with slowly varying amplitude and phase, these derivatives admit precise analytic approximations. It is then possible to design simple analogue electronic circuits to code approximations of the nonlinear computations required by our flat...

  8. Luminance uniformity compensation for OLED panels based on FPGA

    Institute of Scientific and Technical Information of China (English)

    OU Peng; YANG Gang; JIANG Quan; YU Jun-sheng; WU Qi-peng; SHANG Fu-hai; YIN Wei; WANG Jun; ZHONG Jian; LUO Kai-jun

    2009-01-01

    en in program. The irradiance brightness is controlled by changing its irradiance time, and finally, luminance compensation of the panel is realized. The simulation result indicates that the design ismasonable

  9. Diaphragm Based Fiber Bragg Grating Acceleration Sensor with Temperature Compensation.

    Science.gov (United States)

    Li, Tianliang; Tan, Yuegang; Han, Xue; Zheng, Kai; Zhou, Zude

    2017-01-23

    A novel fiber Bragg grating (FBG) sensing-based acceleration sensor has been proposed to simultaneously decouple and measure temperature and acceleration in real-time. This design applied a diaphragm structure and utilized the axial property of a tightly suspended optical fiber, enabling improvement in its sensitivity and resonant frequency and achieve a low cross-sensitivity. The theoretical vibrational model of the sensor has been built, and its design parameters and sensing properties have been analyzed through the numerical analysis. A decoupling method has been presented with consideration of the thermal expansion of the sensor structure to realize temperature compensation. Experimental results show that the temperature sensitivity is 8.66 pm/°C within the range of 30-90 °C. The acceleration sensitivity is 20.189 pm/g with a linearity of 0.764% within the range of 5~65 m/s². The corresponding working bandwidth is 10~200 Hz and its resonant frequency is 600 Hz. This sensor possesses an excellent impact resistance for the cross direction, and the cross-axis sensitivity is below 3.31%. This implementation can avoid the FBG-pasting procedure and overcome its associated shortcomings. The performance of the proposed acceleration sensor can be easily adjusted by modifying their corresponding physical parameters to satisfy requirements from different vibration measurements.

  10. Diaphragm Based Fiber Bragg Grating Acceleration Sensor with Temperature Compensation

    Directory of Open Access Journals (Sweden)

    Tianliang Li

    2017-01-01

    Full Text Available A novel fiber Bragg grating (FBG sensing-based acceleration sensor has been proposed to simultaneously decouple and measure temperature and acceleration in real-time. This design applied a diaphragm structure and utilized the axial property of a tightly suspended optical fiber, enabling improvement in its sensitivity and resonant frequency and achieve a low cross-sensitivity. The theoretical vibrational model of the sensor has been built, and its design parameters and sensing properties have been analyzed through the numerical analysis. A decoupling method has been presented with consideration of the thermal expansion of the sensor structure to realize temperature compensation. Experimental results show that the temperature sensitivity is 8.66 pm/°C within the range of 30–90 °C. The acceleration sensitivity is 20.189 pm/g with a linearity of 0.764% within the range of 5~65 m/s2. The corresponding working bandwidth is 10~200 Hz and its resonant frequency is 600 Hz. This sensor possesses an excellent impact resistance for the cross direction, and the cross-axis sensitivity is below 3.31%. This implementation can avoid the FBG-pasting procedure and overcome its associated shortcomings. The performance of the proposed acceleration sensor can be easily adjusted by modifying their corresponding physical parameters to satisfy requirements from different vibration measurements.

  11. Global motion compensated visual attention-based video watermarking

    Science.gov (United States)

    Oakes, Matthew; Bhowmik, Deepayan; Abhayaratne, Charith

    2016-11-01

    Imperceptibility and robustness are two key but complementary requirements of any watermarking algorithm. Low-strength watermarking yields high imperceptibility but exhibits poor robustness. High-strength watermarking schemes achieve good robustness but often suffer from embedding distortions resulting in poor visual quality in host media. This paper proposes a unique video watermarking algorithm that offers a fine balance between imperceptibility and robustness using motion compensated wavelet-based visual attention model (VAM). The proposed VAM includes spatial cues for visual saliency as well as temporal cues. The spatial modeling uses the spatial wavelet coefficients while the temporal modeling accounts for both local and global motion to arrive at the spatiotemporal VAM for video. The model is then used to develop a video watermarking algorithm, where a two-level watermarking weighting parameter map is generated from the VAM saliency maps using the saliency model and data are embedded into the host image according to the visual attentiveness of each region. By avoiding higher strength watermarking in the visually attentive region, the resulting watermarked video achieves high perceived visual quality while preserving high robustness. The proposed VAM outperforms the state-of-the-art video visual attention methods in joint saliency detection and low computational complexity performance. For the same embedding distortion, the proposed visual attention-based watermarking achieves up to 39% (nonblind) and 22% (blind) improvement in robustness against H.264/AVC compression, compared to existing watermarking methodology that does not use the VAM. The proposed visual attention-based video watermarking results in visual quality similar to that of low-strength watermarking and a robustness similar to those of high-strength watermarking.

  12. Robust Position Tracking for Electro-Hydraulic Drives Based on Generalized Feedforward Compensation Approach

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.;

    2012-01-01

    This paper presents a robust tracking control concept based on accurate feedforward compensation for hydraulic valve-cylinder drives. The proposed feedforward compensator is obtained utilizing a generalized description of the valve flow that takes into account any asymmetry of valves and/or cylin...

  13. [Ecological compensation standard in Dongting Lake region of returning cropland to lake based on emergy analysis].

    Science.gov (United States)

    Mao, De-Hua; Hu, Guang-Wei; Liu, Hui-Jie; Li, Zheng-Zui; Li, Zhi-Long; Tan, Zi-Fang

    2014-02-01

    The annual emergy and currency value of the main ecological service value of returning cropland to lake in Dongting Lake region from 1999 to 2010 was calculated based on emergy analysis. The calculation method of ecological compensation standard was established by calculating annual total emergy of ecological service function increment since the starting year of returning cropland to lake, and the annual ecological compensation standard and compensation area were analyzed from 1999 to 2010. The results indicated that ecological compensation standard from 1999 to 2010 was 40.31-86.48 yuan x m(-2) with the mean of 57.33 yuan x m(-2). The ecological compensation standard presented an increase trend year by year due to the effect of eco-recovery of returning cropland to lake. The ecological compensation standard in the research area presented a swift and steady growth trend after 2005 mainly due to the intensive economy development of Hunan Province, suggesting the value of natural ecological resources would increase along with the development of society and economy. Appling the emergy analysis to research the ecological compensation standard could reveal the dynamics of annual ecological compensation standard, solve the abutment problem of matter flow, energy flow and economic flow, and overcome the subjective and arbitrary of environment economic methods. The empirical research of ecological compensation standard in Dongting Lake region showed that the emergy analysis was feasible and advanced.

  14. Agro-food Quality and Safety Based on Agro-ecological Compensation

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Reflection of the rise of agro-food production costs is analyzed based on the introduction of the quality safety situation of agricultural products in China.Firstly,rise of production costs caused by the demarcation of prohibited areas;secondly,rise of production costs caused by using environment-friendly agricultural inputs;thirdly,rise of production costs caused by quality control;fourthly,rise of production costs caused by product identification.The ecological compensation mechanism which is beneficial to agro-food quality safety is set up according to the principle "the one who is benefited compensates".Firstly,laws and regulations of agricultural production compensation are to be actively perfected.Secondly,experience of developed countries can be borrowed to establish a fiscal transfer payment system of production compensation.Thirdly,ecological agriculture is to be developed to produce products with safety and excellent quality.Since agro-ecological compensation can make up for the costs paid for protecting agro-ecological environment and producing safe agro-products by agro-food producers and is beneficial to motivating producers’ initiative,compensation is made for agricultural producers from compensation objects,compensation scope and compensation mechanism to improve the quality safety level of agricultural products.

  15. Sub-Synchronous Interaction Analysis between DFIG Based Wind Farm and Series Compensated Network

    DEFF Research Database (Denmark)

    Wang, Yun; Wu, Qiuwei; Kang, Shaoli

    2016-01-01

    This paper analyzes the sub-synchronous interaction (SSI) phenomenon between the doubly fed induction generator (DFIG) based wind farm (WF) and the series capacitor compensated network. The possible types of SSI in the DFIG based WF are studied. The factors influencing the SSI of DFIG based WF...... are investigated. The large signal stability and small signal stability of the DFIG based WF with different series compensation (SC) level and wind speed are simulated and compared....

  16. A Method for Dispersion Compensation Based on GLM Theory

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A method used to design the waveguide gratings for dispersion compensation employing GLM theory is briefly described. By using this method a reflective grating is designed, which has both a flat amplitude and a quadratic phase response over the transfer bandwidth.

  17. An autotuning respiration compensation system based on ultrasound image tracking.

    Science.gov (United States)

    Kuo, Chia-Chun; Chuang, Ho-Chiao; Teng, Kuan-Ting; Hsu, Hsiao-Yu; Tien, Der-Chi; Wu, Chih-Jen; Jeng, Shiu-Chen; Chiou, Jeng-Fong

    2016-11-22

    The purpose of this study was to develop an ultrasound image tracking algorithm (UITA) for extracting the exact displacement of internal organs caused by respiratory motion. The program can track organ displacements in real time, and analyze the displacement signals associated with organ displacements via a respiration compensating system (RCS). The ultrasound imaging system is noninvasive and has a high spatial resolution and a high frame rate (around 32 frames/s), which reduces the radiation doses that patients receive during computed tomography and X-ray observations. This allows for the continuous noninvasive observation and compensation of organ displacements simultaneously during a radiation therapy session.This study designed a UITA for tracking the motion of a specific target, such as the human diaphragm. Simulated diaphragm motion driven by a respiration simulation system was observed with an ultrasound imaging system, and then the induced diaphragm displacements were calculated by our proposed UITA. These signals were used to adjust the gain of the RCS so that the amplitudes of the compensation signals were close to the target movements. The inclination angle of the ultrasound probe with respect to the surface of the abdomen affects the results of ultrasound image displacement tracking. Therefore, the displacement of the phantom was verified by a LINAC with different inclination-angle settings of the ultrasound probe. The experimental results indicate that the best inclination angle of the ultrasound probe is 40 degrees, since this results in the target displacement of the ultrasound images being close to the actual target motion. The displacement signals of the tracking phantom and the opposing displacement signals created by the RCS were compared to assess the positioning accuracy of our proposed ultrasound image tracking technique combined with the RCS.When the ultrasound probe was inclined by 40 degrees in simulated respiration experiments using sine

  18. Magneto-optic sensor based on electrogyration compensation and single-quartz crystal

    Science.gov (United States)

    Li, Changsheng; Cui, He; Zhang, Xuan

    2016-11-01

    Magnetooptic sensor based on electrogyration compensation is proposed and experimentally demonstrated by using single quartz crystal. The sensing unit is composed of single quartz crystal and two polarizers. Quartz crystal exhibits magneto-optic, electro-optic and electrogyration effects, thus magneto-optic Faraday rotation angle can be compensated by the electrogyration angle induced by the compensating voltage applied to the crystal. The compensating voltage is sensitive to both the deviation angle between light beam and principal crystalline axis, and the azimuth angle of polarizer. The 50Hz ac magnetic flux density within 267Gs has been measured, the compensating voltage is 0.72V/Gs for a single quartz crystal with a length of 23mm. The proposed sensor has potential application to closed-loop measurement of magnetic field.

  19. A new quantitative model of ecological compensation based on ecosystem capital in Zhejiang Province, China.

    Science.gov (United States)

    Jin, Yan; Huang, Jing-feng; Peng, Dai-liang

    2009-04-01

    Ecological compensation is becoming one of key and multidiscipline issues in the field of resources and environmental management. Considering the change relation between gross domestic product (GDP) and ecological capital (EC) based on remote sensing estimation, we construct a new quantitative estimate model for ecological compensation, using county as study unit, and determine standard value so as to evaluate ecological compensation from 2001 to 2004 in Zhejiang Province, China. Spatial differences of the ecological compensation were significant among all the counties or districts. This model fills up the gap in the field of quantitative evaluation of regional ecological compensation and provides a feasible way to reconcile the conflicts among benefits in the economic, social, and ecological sectors.

  20. Forecast of Frost Days Based on Monthly Temperatures

    Science.gov (United States)

    Castellanos, M. T.; Tarquis, A. M.; Morató, M. C.; Saa-Requejo, A.

    2009-04-01

    Although frost can cause considerable crop damage and mitigation practices against forecasted frost exist, frost forecasting technologies have not changed for many years. The paper reports a new method to forecast the monthly number of frost days (FD) for several meteorological stations at Community of Madrid (Spain) based on successive application of two models. The first one is a stochastic model, autoregressive integrated moving average (ARIMA), that forecasts monthly minimum absolute temperature (tmin) and monthly average of minimum temperature (tminav) following Box-Jenkins methodology. The second model relates these monthly temperatures to minimum daily temperature distribution during one month. Three ARIMA models were identified for the time series analyzed with a stational period correspondent to one year. They present the same stational behavior (moving average differenced model) and different non-stational part: autoregressive model (Model 1), moving average differenced model (Model 2) and autoregressive and moving average model (Model 3). At the same time, the results point out that minimum daily temperature (tdmin), for the meteorological stations studied, followed a normal distribution each month with a very similar standard deviation through years. This standard deviation obtained for each station and each month could be used as a risk index for cold months. The application of Model 1 to predict minimum monthly temperatures showed the best FD forecast. This procedure provides a tool for crop managers and crop insurance companies to asses the risk of frost frequency and intensity, so that they can take steps to mitigate against frost damage and estimated the damage that frost would cost. This research was supported by Comunidad de Madrid Research Project 076/92. The cooperation of the Spanish National Meteorological Institute and the Spanish Ministerio de Agricultura, Pesca y Alimentation (MAPA) is gratefully acknowledged.

  1. Estimating monthly temperature using point based interpolation techniques

    Science.gov (United States)

    Saaban, Azizan; Mah Hashim, Noridayu; Murat, Rusdi Indra Zuhdi

    2013-04-01

    This paper discusses the use of point based interpolation to estimate the value of temperature at an unallocated meteorology stations in Peninsular Malaysia using data of year 2010 collected from the Malaysian Meteorology Department. Two point based interpolation methods which are Inverse Distance Weighted (IDW) and Radial Basis Function (RBF) are considered. The accuracy of the methods is evaluated using Root Mean Square Error (RMSE). The results show that RBF with thin plate spline model is suitable to be used as temperature estimator for the months of January and December, while RBF with multiquadric model is suitable to estimate the temperature for the rest of the months.

  2. It Could Work: Teacher Performance-Based Compensation in a New York Charter School

    Science.gov (United States)

    Tryjankowski, Anne Marie; Henry, Julie J.; Verrall, Eon

    2012-01-01

    Performance-based compensation systems have been under discussion for years and are now a required component of any state plan for Race to the Top funds. This article describes a system of performance-based compensation that has been in place at a K-12 school for the past four years. The system was developed by a team of teachers, union members,…

  3. Friction compensation design based on state observer and adaptive law for high-accuracy positioning system

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Friction is one of the main factors that affect the positioning accuracy of motion system. Friction compensation based on friction model is usually adopted to eliminate the nonlinear effect of friction. This paper presents a proportional-plus-derivative (PD) feedback controller with a friction compensator based on LuGre friction model. We also design a state observer to observe the unknown state of LuGre friction model, and adopt a parameter adaptive law and off-line approximation to estimate the parameters of LuGre friction model. Comparative experiments are carried out among our proposed controller, PD controller with friction compensation based on classical friction model, and PD controller without friction compensation. Experimental results demonstrate that our proposed controller can achieve better performance, especially higher positioning accuracy.

  4. Adaptive filter design based on the LMS algorithm for delay elimination in TCR/FC compensators.

    Science.gov (United States)

    Hooshmand, Rahmat Allah; Torabian Esfahani, Mahdi

    2011-04-01

    Thyristor controlled reactor with fixed capacitor (TCR/FC) compensators have the capability of compensating reactive power and improving power quality phenomena. Delay in the response of such compensators degrades their performance. In this paper, a new method based on adaptive filters (AF) is proposed in order to eliminate delay and increase the response of the TCR compensator. The algorithm designed for the adaptive filters is performed based on the least mean square (LMS) algorithm. In this design, instead of fixed capacitors, band-pass LC filters are used. To evaluate the filter, a TCR/FC compensator was used for nonlinear and time varying loads of electric arc furnaces (EAFs). These loads caused occurrence of power quality phenomena in the supplying system, such as voltage fluctuation and flicker, odd and even harmonics and unbalancing in voltage and current. The above design was implemented in a realistic system model of a steel complex. The simulation results show that applying the proposed control in the TCR/FC compensator efficiently eliminated delay in the response and improved the performance of the compensator in the power system.

  5. All-channel tunable optical dispersion compensator based on linear translation of a waveguide grating router.

    Science.gov (United States)

    Sinefeld, David; Ben-Ezra, Shalva; Doerr, Christopher R; Marom, Dan M

    2011-04-15

    We propose and demonstrate a compact tunable optical dispersion compensation (TODC) device with a 100 GHz free spectral range capable of mitigating chromatic dispersion impairments. The TODC is based on longitudinal movement of a waveguide grating router, resulting in chromatic dispersion compensation of ±1000 ps/nm. We employed our TODC device for compensating 42.8 Gbit/sec differential phase-shifting keying signal, transmitted over 50 km fiber with a -2 dB power penalty at 10⁻⁹.

  6. Translational Motion Compensation for Ballistic Targets Based on Delayed Conjugated Multiplication

    Directory of Open Access Journals (Sweden)

    He Si-san

    2014-10-01

    Full Text Available The micro-motion is combined with the high velocity of translation motion for ballistic targets. The translation motion should be compensated for micro-Doppler information extraction. A new method based on delay conjugate multiplication is proposed to compensate the translation motion of ballistic target. By delay conjugate multiplication of the received signal, the micro-Doppler information are canceled out and the translation motion parameters estimation problem is transformed as an multi-polynomial phase signal parameters estimation problem. Thus, the translation parameters can be estimated. Simulation results suggest that the proposed algorithm can achieve high-precision compensation for ballistic targets under low SNR.

  7. Imaging Method Based on Time Reversal Channel Compensation

    Directory of Open Access Journals (Sweden)

    Bing Li

    2015-01-01

    Full Text Available The conventional time reversal imaging (TRI method builds imaging function by using the maximal value of signal amplitude. In this circumstance, some remote targets are missed (near-far problem or low resolution is obtained in lossy and/or dispersive media, and too many transceivers are employed to locate targets, which increases the complexity and cost of system. To solve these problems, a novel TRI algorithm is presented in this paper. In order to achieve a high resolution, the signal amplitude corresponding to focal time observed at target position is used to reconstruct the target image. For disposing near-far problem and suppressing spurious images, combining with cross-correlation property and amplitude compensation, channel compensation function (CCF is introduced. Moreover, the complexity and cost of system are reduced by employing only five transceivers to detect four targets whose number is close to that of transceivers. For the sake of demonstrating the practicability of the proposed analytical framework, the numerical experiments are actualized in both nondispersive-lossless (NDL media and dispersive-conductive (DPC media. Results show that the performance of the proposed method is superior to that of conventional TRI algorithm even under few echo signals.

  8. Baseline Signal Reconstruction for Temperature Compensation in Lamb Wave-Based Damage Detection.

    Science.gov (United States)

    Liu, Guoqiang; Xiao, Yingchun; Zhang, Hua; Ren, Gexue

    2016-08-11

    Temperature variations have significant effects on propagation of Lamb wave and therefore can severely limit the damage detection for Lamb wave. In order to mitigate the temperature effect, a temperature compensation method based on baseline signal reconstruction is developed for Lamb wave-based damage detection. The method is a reconstruction of a baseline signal at the temperature of current signal. In other words, it compensates the baseline signal to the temperature of current signal. The Hilbert transform is used to compensate the phase of baseline signal. The Orthogonal matching pursuit (OMP) is used to compensate the amplitude of baseline signal. Experiments were conducted on two composite panels to validate the effectiveness of the proposed method. Results show that the proposed method could effectively work for temperature intervals of at least 18 °C with the baseline signal temperature as the center, and can be applied to the actual damage detection.

  9. Baseline Signal Reconstruction for Temperature Compensation in Lamb Wave-Based Damage Detection

    Directory of Open Access Journals (Sweden)

    Guoqiang Liu

    2016-08-01

    Full Text Available Temperature variations have significant effects on propagation of Lamb wave and therefore can severely limit the damage detection for Lamb wave. In order to mitigate the temperature effect, a temperature compensation method based on baseline signal reconstruction is developed for Lamb wave-based damage detection. The method is a reconstruction of a baseline signal at the temperature of current signal. In other words, it compensates the baseline signal to the temperature of current signal. The Hilbert transform is used to compensate the phase of baseline signal. The Orthogonal matching pursuit (OMP is used to compensate the amplitude of baseline signal. Experiments were conducted on two composite panels to validate the effectiveness of the proposed method. Results show that the proposed method could effectively work for temperature intervals of at least 18 °C with the baseline signal temperature as the center, and can be applied to the actual damage detection.

  10. Induction motor IFOC based speed-controlled drive with asymptotic disturbance compensation

    Directory of Open Access Journals (Sweden)

    Stojić Đorđe M.

    2012-01-01

    Full Text Available This paper presents the design of digitally controlled speed electrical drive, with the asymptotic compensation of external disturbances, implemented by using the IFOC (Indirect Field Oriented Control torque controlled induction motor. The asymptotic disturbance compensation is achieved by using the DOB (Disturbance Observer with the IMP (Internal Model Principle. When compared to the existing IMP-based DOB solutions, in this paper the robust stability and disturbance compensation are improved by implementing the minimal order DOB filter. Also, the IMP-based DOB design is improved by employing the asymptotic compensation of all elemental or more complex external disturbances. The dynamic model of the IFOC torque electrical drive is, also, included in the speed-controller and DOB section design. The simulation and experimental measurements presented in the paper illustrate the effectiveness and robustness of the proposed control scheme.

  11. A Novel Gravity Compensation Method for High Precision Free-INS Based on "Extreme Learning Machine".

    Science.gov (United States)

    Zhou, Xiao; Yang, Gongliu; Cai, Qingzhong; Wang, Jing

    2016-11-29

    In recent years, with the emergency of high precision inertial sensors (accelerometers and gyros), gravity compensation has become a major source influencing the navigation accuracy in inertial navigation systems (INS), especially for high-precision INS. This paper presents preliminary results concerning the effect of gravity disturbance on INS. Meanwhile, this paper proposes a novel gravity compensation method for high-precision INS, which estimates the gravity disturbance on the track using the extreme learning machine (ELM) method based on measured gravity data on the geoid and processes the gravity disturbance to the height where INS has an upward continuation, then compensates the obtained gravity disturbance into the error equations of INS to restrain the INS error propagation. The estimation accuracy of the gravity disturbance data is verified by numerical tests. The root mean square error (RMSE) of the ELM estimation method can be improved by 23% and 44% compared with the bilinear interpolation method in plain and mountain areas, respectively. To further validate the proposed gravity compensation method, field experiments with an experimental vehicle were carried out in two regions. Test 1 was carried out in a plain area and Test 2 in a mountain area. The field experiment results also prove that the proposed gravity compensation method can significantly improve the positioning accuracy. During the 2-h field experiments, the positioning accuracy can be improved by 13% and 29% respectively, in Tests 1 and 2, when the navigation scheme is compensated by the proposed gravity compensation method.

  12. Power Quality Enhancement in Wind Connected Grid System Interface Based On Static Switched Filter Compensator (SSFC

    Directory of Open Access Journals (Sweden)

    Lakshmi Prasanna Vatti

    2014-11-01

    Full Text Available Wind energy has become one of the significant alternative renewable energy resources because of its abundance and the strong drive for its commercialization. Dynamic electric load variations and wind velocity excursions cause excessive changes in the prime mover kinetic energy and the corresponding electrical power injected into the AC grid utility system. In this paper, a scheme based on the low cost static switched filter compensator (SSFC is presented for voltage sag/swell compensation, power factor improvement in distribution grid networks with the dispersed wind energy interface. The SSFC scheme is based on an intermittent switching process between two shunt capacitor banks to be one of them in parallel with the capacitor of a tuned arm filter. Two regulators based on a tri- loop dynamic error driven inter-coupled weighted modified proportional-integralderivative (PID controller which is used to modulate the PWM. The Static Switched Filter Compensation (SSFC compensation scheme which enhances the system power quality has been fully validated using MATLAB–Simulink. The effectiveness of this compensation scheme approach is demonstrated using a study case of 3 bus system. Simulation results show that there is improvement in harmonics reduction, voltage sag/swell compensation, power factor improvement at generator bus, load bus, and infinite bus respectively

  13. Simulation of Networked Control System based on Smith Compensator and Single Neuron Incomplete Differential Forward PID

    Directory of Open Access Journals (Sweden)

    Haitao Zhang

    2011-12-01

    Full Text Available In the networked control system with random time delay in forward and feedback channels, a kind of controller based on Smith compensator and signal neuron incomplete differential forward PID is presented. First, using root locus method and simulink simulation software, the influences of network’s time delay on the system stability and dynamic performance are analyzed. Then, combined with incomplete differential forward PID control algorithm, Smith compensation model is established. Compared with existing Smith compensator, the proposed control model is easy to be implemented, and can also get better control performance in the case of miss-matching compensator model. Finally, the simulation research on a DC motor is done, and the simulation results show the effectiveness of the proposed method.

  14. Power constrained contrast enhancement based on brightness compensated contrast-tone mapping operation

    Science.gov (United States)

    Jung, Cheolkon; Su, Haonan; Wang, Lu; Ke, Peng

    2016-09-01

    We propose power constrained contrast enhancement based on brightness compensated contrast-tone mapping operation (BCCTMO). We adopt brightness compensation to restore the original perceptual luminance and combine tone mapping with contrast enhancement to improve image quality. First, we increase pixel values to compensate for the reduced brightness caused by backlight dimming while maintaining the perceived luminance. Then we perform a contrast-tone mapping operation to reduce the information loss caused by the brightness compensation and enhance contrast in images. Finally, we conduct color scaling to reproduce natural colors. We implement BCCTMO on an Android tablet with an LCD display using mathematical approximation. Experimental results demonstrate that BCCTMO produces high-quality images while minimizing distortions and saving power compared with state-of-the-art methods.

  15. Measure of Watershed Ecological Compensation Standard Based on WTP and WTA

    Institute of Scientific and Technical Information of China (English)

    Dawei; XU; Jinfang; RONG; Na; YANG; Wen; ZHANG

    2013-01-01

    In this paper,Liao River Basin was taken as the research object and field surveys were conducted in Fudedian,the source of Liao river mainstream and Panjin,the estuary of Liao River. Through the questionnaires,the willingness to pay ( WTP) and willingness to accept ( WTA) of the residents in Liao River Basin were analyzed. Then based on analysis of the existing ecological compensation standard measuring methods,the WTP and WTA using contingent valuation method ( CVM) were measured and analyzed. Without considering other factors,and based on using the nonparametric estimation method,it was concluded the ecological compensation standard of Liao River Basin was 160. 72 yuan/person·years. When considering other factors,using the parametric estimation we obtain that the ecological compensation standard of Liao River Basin was 255. 97 yuan/person·years. Measuring the respondents’ WTP and WTA at the same time and processing the average can actually reflect the respondents’ real WTP,thus to a certain extent solving the problems of high compensation caused by formulating ecological compensation standards according to measuring WTP of respondents separately. In addition,the policy suggestions have been proposed from three aspects including financial transfer payment,ecological compensation forms and public participation system. This will not only protect residents’ right to know and strengthen public participation and supervision,but also benefit the comprehensive implementation of ecological environment of Liao River Basin and establishment of a long-term mechanism of water resources protection.

  16. Vision correction for computer users based on image pre-compensation with changing pupil size.

    Science.gov (United States)

    Huang, Jian; Barreto, Armando; Alonso, Miguel; Adjouadi, Malek

    2011-01-01

    Many computer users suffer varying degrees of visual impairment, which hinder their interaction with computers. In contrast with available methods of vision correction (spectacles, contact lenses, LASIK, etc.), this paper proposes a vision correction method for computer users based on image pre-compensation. The blurring caused by visual aberration is counteracted through the pre-compensation performed on images displayed on the computer screen. The pre-compensation model used is based on the visual aberration of the user's eye, which can be measured by a wavefront analyzer. However, the aberration measured is associated with one specific pupil size. If the pupil has a different size during viewing of the pre-compensated images, the pre-compensation model should also be modified to sustain appropriate performance. In order to solve this problem, an adjustment of the wavefront function used for pre-compensation is implemented to match the viewing pupil size. The efficiency of these adjustments is evaluated with an "artificial eye" (high resolution camera). Results indicate that the adjustment used is successful and significantly improves the images perceived and recorded by the artificial eye.

  17. Dispersion-compensated meta-holograms based on detour phase

    CERN Document Server

    Khorasaninejad, Mohammadreza; Kanhaiya, Pritpal; Capasso, Federico

    2016-01-01

    Subwavelength structured surfaces, known as metasurfaces, hold promise for future compact and optically thin devices with versatile functionalities. Here, by revisiting the concept of detour phase at the basis of the first computer generated holograms we have designed high-performance transmissive dielectric meta-holograms with new functionalities. In one class of such devices wavelength- independent phase masks have been generated by compensating the inherent dispersion of the detour phase with that of the subwavelength structures. This leads to broadband operation from the visible to the near infrared with efficiency as high as 75% in the 1000 to 1400 nm range. We have also shown that we can fully control the effective focal length of the imaging optical system by incorporating a lens-like function in the meta-hologram. In a second class of devices we have incorporated in the phase map a geometric phase to achieve for the first time chiral imaging: the projection of different images depends on the handednes...

  18. The research of moving object detection based on background difference compensation

    Science.gov (United States)

    Song, Yan-bin; Ying, Jie; Lu, Lin-li

    2013-08-01

    Moving object detection was implemented in dynamic background based on background difference compensation. Background differential can effectively segment the moving object in static background. But in moving video, the camera motion causes corresponding movement of the target and background, which makes the prospect moving object hard to separate from the background. In order to detect moving object, we can compensate the movement of the background and transfer the dynamic background to static. Moving object detection in static background image was implemented using a new weights updating method that the weights were updated during a certain period. This method based on classical Gaussian mixture model improved the efficiency of image segmentation greatly. Moving object detection in dynamic background was realized using background differential compensation. The global motion of the background was established according to the affined parameters model. The model parameters were estimated by feature points matching based on the search strategy. Invalid matching points were eliminated using the method of distance consistency. Backward mapping was used to get the motion parameters of the background. After compensation of the background with the global motion parameters, frame difference between the current frame and the background can detect moving objects effectively. Experiments were done on computer with the programming tools of VS2010 and MATLAB. Experimental results showed that the algorithm based on differential compensation was effective.

  19. Design principle of high-precision flexure mechanisms based on parasitic-motion compensation

    Science.gov (United States)

    Li, Shouzhong; Yu, Jingjun

    2014-07-01

    In design of flexure mechanism, diminishing the parasitic-motion is a key point to improve the accuracy. However, most of existing topics concentrate on improving the accuracy of linear-motion flexure mechanisms via compensating the parasitic error, but few research the multi-dimensional flexure mechanisms. A general design principle and method for high-precision flexure mechanisms based on the parasitic-motion compensation is presented, and the proposed method can compensate the parasitic rotation in company with translation, or the parasitic translation in company with rotation, or both. The crucial step for the method is that the parasitic motion of a flexure mechanism is formulated and evaluated in terms of its compliance. The overall compliance matrix of a general flexure mechanism is formulated by using screw theory firstly, then the criteria for the parasitic motions is introduced by analyzing the characteristics of the resultant compliance matrix as well as with aid of the concept of instantaneous rotation center. Subsequently, a compliance-based compensation approach for reducing parasitic-motion is addressed as the most important part. The design principles and procedure are further discussed to help with improving the accuracy of flexure mechanisms, and case studies are provided to illustrate this method. Finally, an analytical verification is provided to demonstrate that the symmetry design philosophy widely used in flexure design can effectively improve accuracy in terms of the proposed method. The proposed compensation method can be well used to diminish the parasitic-motion of multi-dimensional flexure mechanisms.

  20. Hysteresis Compensation of Piezoresistive Carbon Nanotube/Polydimethylsiloxane Composite-Based Force Sensors.

    Science.gov (United States)

    Kim, Ji-Sik; Kim, Gi-Woo

    2017-01-24

    This paper provides a preliminary study on the hysteresis compensation of a piezoresistive silicon-based polymer composite, poly(dimethylsiloxane) dispersed with carbon nanotubes (CNTs), to demonstrate its feasibility as a conductive composite (i.e., a force-sensitive resistor) for force sensors. In this study, the potential use of the nanotube/polydimethylsiloxane (CNT/PDMS) as a force sensor is evaluated for the first time. The experimental results show that the electrical resistance of the CNT/PDMS composite changes in response to sinusoidal loading and static compressive load. The compensated output based on the Duhem hysteresis model shows a linear relationship. This simple hysteresis model can compensate for the nonlinear frequency-dependent hysteresis phenomenon when a dynamic sinusoidal force input is applied.

  1. Hysteresis Compensation of Piezoresistive Carbon Nanotube/Polydimethylsiloxane Composite-Based Force Sensors

    Directory of Open Access Journals (Sweden)

    Ji-Sik Kim

    2017-01-01

    Full Text Available This paper provides a preliminary study on the hysteresis compensation of a piezoresistive silicon-based polymer composite, poly(dimethylsiloxane dispersed with carbon nanotubes (CNTs, to demonstrate its feasibility as a conductive composite (i.e., a force-sensitive resistor for force sensors. In this study, the potential use of the nanotube/polydimethylsiloxane (CNT/PDMS as a force sensor is evaluated for the first time. The experimental results show that the electrical resistance of the CNT/PDMS composite changes in response to sinusoidal loading and static compressive load. The compensated output based on the Duhem hysteresis model shows a linear relationship. This simple hysteresis model can compensate for the nonlinear frequency-dependent hysteresis phenomenon when a dynamic sinusoidal force input is applied.

  2. A New Approach of Error Compensation on NC Machining Based on Memetic Computation

    Directory of Open Access Journals (Sweden)

    Huanglin Zeng

    2013-04-01

    Full Text Available This paper is a study of the application of Memetic computation integrating and coordinating intelligence algorithms to solve the problems of error compensation for a high-precision numeral control machining system. The primary focus is on development of integrated intelligent computation approach to set up an error compensation system of a numeral control machine tool based on a dynamic feedback neural network. Optimization of error measurement points of a numeral control machine tool is realized by way of application of error variable attribute reduction on rough set theory. A principal component analysis is used for data compression and feature extraction to reduce the input dimension of a dynamic feedback neural network. A dynamic feedback neural network is trained on ant colony algorithm so that network can converge to get a global optimum. Positioning error caused in thermal deformation compensation capabilities were tested using industry standard equipment and procedures. The results obtained shows that this approach can effectively improve compensation precision and real time of error compensation on machine tools.

  3. A method for aircraft magnetic interference compensation based on small signal model and LMS algorithm

    Institute of Scientific and Technical Information of China (English)

    Zhou Jianjun; Lin Chunsheng; Chen Hao

    2014-01-01

    Aeromagnetic interference could not be compensated effectively if the precision of parameters which are solved by the aircraft magnetic field model is low. In order to improve the compensation effect under this condition, a method based on small signal model and least mean square (LMS) algorithm is proposed. According to the method, the initial values of adaptive filter’s weight vector are calculated with the solved model parameters through small signal model at first, then the small amount of direction cosine and its derivative are set as the input of the filter, and the small amount of the interference is set as the filter’s expected vector. After that, the aircraft mag-netic interference is compensated by LMS algorithm. Finally, the method is verified by simulation and experiment. The result shows that the compensation effect can be improved obviously by the LMS algorithm when original solved parameters have low precision. The method can further improve the compensation effect even if the solved parameters have high precision.

  4. Inertial measurement unit–based iterative pose compensation algorithm for low-cost modular manipulator

    Directory of Open Access Journals (Sweden)

    Yunhan Lin

    2016-01-01

    Full Text Available It is a necessary mean to realize the accurate motion control of the manipulator which uses end-effector pose correction method and compensation method. In this article, first, we established the kinematic model and error model of the modular manipulator (WUST-ARM, and then we discussed the measurement methods and precision of the inertial measurement unit sensor. The inertial measurement unit sensor is mounted on the end-effector of modular manipulator, to get the real-time pose of the end-effector. At last, a new inertial measurement unit–based iterative pose compensation algorithm is proposed. By applying this algorithm in the pose compensation experiment of modular manipulator which is composed of low-cost rotation joints, the results show that the inertial measurement unit can obtain a higher precision when in static state; it will accurately feedback to the control system with an accurate error compensation angle after a brief delay when the end-effector moves to the target point, and after compensation, the precision errors of roll angle, pitch angle, and yaw angle are reached at 0.05°, 0.01°, and 0.27° respectively. It proves that this low-cost method provides a new solution to improve the end-effector pose of low-cost modular manipulator.

  5. Output regulation for linear singular systems using dual-observer based compensators

    Science.gov (United States)

    Deutscher, Joachim

    2013-05-01

    In this article, the output regulation problem is solved for singular systems by using dual observer-based compensators. This has the advantage that output regulation can be achieved under weak conditions. Namely, different from previous approaches, an implementable compensator can be directly determined in form of a classical state space model without a transformation into Weierstrass-Kronecker canonical form. Furthermore, the impulse controllability and observability of the singular system is not required and the output to be controlled needs not be measurable. The results of the article are demonstrated by means of a simple mechanical system.

  6. Active and passive compensation of APPLE II-introduced multipole errors through beam-based measurement

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Ting-Yi; Huang, Szu-Jung; Fu, Huang-Wen; Chang, Ho-Ping; Chang, Cheng-Hsiang [National Synchrotron Radiation Research Center, Hsinchu Science Park, Hsinchu 30076, Taiwan (China); Hwang, Ching-Shiang [National Synchrotron Radiation Research Center, Hsinchu Science Park, Hsinchu 30076, Taiwan (China); Department of Electrophysics, National Chiao Tung University, Hsinchu 30050, Taiwan (China)

    2016-08-01

    The effect of an APPLE II-type elliptically polarized undulator (EPU) on the beam dynamics were investigated using active and passive methods. To reduce the tune shift and improve the injection efficiency, dynamic multipole errors were compensated using L-shaped iron shims, which resulted in stable top-up operation for a minimum gap. The skew quadrupole error was compensated using a multipole corrector, which was located downstream of the EPU for minimizing betatron coupling, and it ensured the enhancement of the synchrotron radiation brightness. The investigation methods, a numerical simulation algorithm, a multipole error correction method, and the beam-based measurement results are discussed.

  7. A Fuzzy PI Speed Controller based on Feedback Compensation Strategy for PMSM

    Directory of Open Access Journals (Sweden)

    Ou Sheng

    2015-05-01

    Full Text Available in order to solve the problem of robustness or anti-disturbance of the traditional PI speed controller in the permanent magnet synchronous motor. A fuzzy PI speed controller based on load torque feedback compensation is proposed for the permanent magnet synchronous motor. The combination of fuzzy PI control strategy and load feedback compensation method can enhance the robustness and disturbance rejection of the speed loop. According to the validated results of simulation and experiments, by using this PMSM speed controller, the robustness of the system speed control was enhanced markedly, and the capacity of anti-disturbance was also improved significantly.

  8. A RBFNN-Based Adaptive Disturbance Compensation Approach Applied to Magnetic Suspension Inertially Stabilized Platform

    Directory of Open Access Journals (Sweden)

    Quanqi Mu

    2014-01-01

    Full Text Available Compared with traditional mechanical inertially stabilized platform (ISP, magnetic suspension ISP (MSISP can absorb high frequency vibrations via a magnetic suspension bearing system with five degrees of freedom between azimuth and pitch gimbals. However, force acting between rotor and stator will introduce coupling torque to roll and pitch gimbals. Since the disturbance of magnetic bearings has strong nonlinearity, classic state feedback control algorithm cannot bring higher precision control for MSISP. In order to enhance the control accuracy for MSISP, a disturbance compensator based on radial basis function neural network (RBFNN is developed to compensate for the disturbance. Using the Lyapunov theorem, the weighting matrix of RBFNN can be updated online. Therefore, the RBFNN can be constructed without priori training. At last, simulations and experiment results validate that the compensation method proposed in this paper can improve ISP accuracy significantly.

  9. Diamagnetic measurements based on the compensation of TF current diffusion in J-TEXT

    Science.gov (United States)

    Zhu, L. Z.; Chen, Z. P.; Li, F. M.; Liu, H.; Chen, Z. Y.; Zhuang, G.

    2016-11-01

    Due to the existence both of toroidal ripples and toroidal field (TF) current diffusion, the toroidal flux changes with time when the TF current is at the flat-top. A diamagnetic measurement based on the compensation of TF current diffusion has been built in J-TEXT to solve this problem. The measurement system includes a double-loop installed in the vacuum vessel and an array of small printed circuit board (PCB) magnetic probes placed on the mid-plane of one TF coil. A model was proposed to analyze and compensate the effect of TF current diffusion. Experiment results show that the residual flux is about 1 × 10-4 Wb after the compensation and it can meet the need of diamagnetic measurement in J-TEXT.

  10. A compensation approach to the tool used in autoclave based on FEA

    Institute of Scientific and Technical Information of China (English)

    Zhang Ji; Li Yingguang; Li Nanya; and Liao Wenhe

    2012-01-01

    Optimization of the curing process can not control the deformation of composite part prepared in autoclave accurately. And traditional "trial-and-error" tool surface compensation approach is low efficiency, high cost and can not control part deformation quantificationally. In order to address these issues, tool compensation approach based on FEA is presented. Model of multi-field coupling relationship in autoclave is realized. And finite element analysis model of composite part's curing process is developed to analyze part deformation. According to displacement of the part surface nodes after deformation, tool surface which compensated by the displacement of composite part which analyzed by FEA is used to control part deformation. A cylindrical composite part is ana- lyzed to verify the approach, and the result proves the correctness and validity of the approach.

  11. A 10 MHz ripple-based on-time controlled buck converter with dual ripple compensation

    Institute of Scientific and Technical Information of China (English)

    Lü Danzhu; Yu Jiale; Hong Zhiliang

    2013-01-01

    A 10 MHz ripple-based on-time controlled buck converter is presented.A novel low-cost dual ripple compensation,which consists of coupling capacitor compensation and passive equivalent series resistance compensation,is proposed to achieve a fast load transient response and robust stability simultaneously.Implemented in a 2P4M 0.35 μm CMOS process,the converter achieves fix-frequency output with a ripple of below 10 mV and an overshoot of 10 mV at 400 mA step load transient response.With width optimization of the power transistors in an ultra-heavy load and PFM control in a light load,the efficiency stays at over 83% for a load range from 20 mA to 1.5 A and the peak efficiency reaches 90.16%.

  12. A High-precision Motion Compensation Method for SAR Based on Image Intensity Optimization

    Directory of Open Access Journals (Sweden)

    Hu Ke-bin

    2015-02-01

    Full Text Available Owing to the platform instability and precision limitations of motion sensors, motion errors negatively affect the quality of synthetic aperture radar (SAR images. The autofocus Back Projection (BP algorithm based on the optimization of image sharpness compensates for motion errors through phase error estimation. This method can attain relatively good performance, while assuming the same phase error for all pixels, i.e., it ignores the spatial variance of motion errors. To overcome this drawback, a high-precision motion error compensation method is presented in this study. In the proposed method, the Antenna Phase Centers (APC are estimated via optimization using the criterion of maximum image intensity. Then, the estimated APCs are applied for BP imaging. Because the APC estimation equals the range history estimation for each pixel, high-precision phase compensation for every pixel can be achieved. Point-target simulations and processing of experimental data validate the effectiveness of the proposed method.

  13. Modelling raster-based monthly water balance components for Europe

    Energy Technology Data Exchange (ETDEWEB)

    Ulmen, C.

    2000-11-01

    The terrestrial runoff component is a comparatively small but sensitive and thus significant quantity in the global energy and water cycle at the interface between landmass and atmosphere. As opposed to soil moisture and evapotranspiration which critically determine water vapour fluxes and thus water and energy transport, it can be measured as an integrated quantity over a large area, i.e. the river basin. This peculiarity makes terrestrial runoff ideally suited for the calibration, verification and validation of general circulation models (GCMs). Gauging stations are not homogeneously distributed in space. Moreover, time series are not necessarily continuously measured nor do they in general have overlapping time periods. To overcome this problems with regard to regular grid spacing used in GCMs, different methods can be applied to transform irregular data to regular so called gridded runoff fields. The present work aims to directly compute the gridded components of the monthly water balance (including gridded runoff fields) for Europe by application of the well-established raster-based macro-scale water balance model WABIMON used at the Federal Institute of Hydrology, Germany. Model calibration and validation is performed by separated examination of 29 representative European catchments. Results indicate a general applicability of the model delivering reliable overall patterns and integrated quantities on a monthly basis. For time steps less then too weeks further research and structural improvements of the model are suggested. (orig.)

  14. The Dutch Memory Compensation Questionnaire: Psychometric properties and regression-based norms

    NARCIS (Netherlands)

    Van der Elst, Wim; Hoogenhout, Esther; Dixon, Robert; De Groot, Renate; Jolles, Jelle

    2010-01-01

    Van der Elst, W., Hoogenhout, E. M., Dixon, R. A., De Groot, R. H. M., & Jolles, J. (2011). The Dutch Memory Compensation Questionnaire: Psychometric properties and regression-based norms. Assessment, 18(4), 517-529. DOI:10.1177/1073191110370116.

  15. Enhanced control strategy for MMC-based STATCOM for unbalanced load compensation

    DEFF Research Database (Denmark)

    Nieves, M.; Maza, J.M.; Mauricio, J.M.;

    2014-01-01

    as required for load unbalance compensation. This paper proposes an improved balancing strategy for the delta configuration to overcome this situation based on the injection of a third harmonic zero sequence current. Simulation results have proved the effectiveness of the proposal even where different...

  16. Reliability of electrode wear compensation based on material removal per discharge in micro EDM milling

    DEFF Research Database (Denmark)

    Bissacco, Giuliano; Tristo, G.; Hansen, Hans Nørgaard

    2013-01-01

    This paper investigates the reliability of workpiece material removal per discharge (MRD) estimation for application in electrode wear compensation based on workpiece material removal. An experimental investigation involving discharge counting and automatic on the machine measurement of removed...... removal simulation tool was developed and validated....

  17. The Influence of Teacher Motivation in the Context of Performance-Based Compensation

    Science.gov (United States)

    Glass, Jason E.

    2011-01-01

    The purpose of this study was to examine teacher motivation in the context of performance-based compensation systems. The researcher specifically sought to address four research questions: 1. To what extent are teachers motivated for behavioristic/economic reasons and extrinsic rewards? 2. To what extent are teachers motivated for altruistic/PSM…

  18. Creative compensation

    Energy Technology Data Exchange (ETDEWEB)

    Coll, D

    1994-09-19

    A discussion is presented of executive compensation in Canada's petroleum industry. Mandatory disclosure of executive compensation and benefits is regulated by the Ontario Securities Commission. Examination of the compensation packages of 80 oilpatch CEOs shows a clear difference in philosophy between large and small companies. Larger companies pay larger salaries, offer pension plans, and reward long-term loyalty. Within smaller companies, compensation tends to be linked with stock performance. Trends in compensation are to lower base salaries with more variables such as bonuses, cash incentives and gain-sharing programs. Increasing shareholder scrutiny is prompting more stringent guidelines on stock option plans. Some companies place performance conditions on stock vesting. Another option is to grant premium priced options to executives, to increase the gains required for the executive to post a profit. Other comapanies are granting stock options to their field personnel, or are granting stock to all employees. Directors are playing an increasing role in executive compensation. 4 tabs.

  19. Design of jitter compensation algorithm for robot vision based on optical flow and Kalman filter.

    Science.gov (United States)

    Wang, B R; Jin, Y L; Shao, D L; Xu, Y

    2014-01-01

    Image jitters occur in the video of the autonomous robot moving on bricks road, which will reduce robot operation precision based on vision. In order to compensate the image jitters, the affine transformation kinematics were established for obtaining the six image motion parameters. The feature point pair detecting method was designed based on Eigen-value of the feature windows gradient matrix, and the motion parameters equation was solved using the least square method and the matching point pairs got based on the optical flow. The condition number of coefficient matrix was proposed to quantificationally analyse the effect of matching errors on parameters solving errors. Kalman filter was adopted to smooth image motion parameters. Computing cases show that more point pairs are beneficial for getting more precise motion parameters. The integrated jitters compensation software was developed with feature points detecting in subwindow. And practical experiments were conducted on two mobile robots. Results show that the compensation costing time is less than frame sample time and Kalman filter is valid for robot vision jitters compensation.

  20. Design of Jitter Compensation Algorithm for Robot Vision Based on Optical Flow and Kalman Filter

    Directory of Open Access Journals (Sweden)

    B. R. Wang

    2014-01-01

    Full Text Available Image jitters occur in the video of the autonomous robot moving on bricks road, which will reduce robot operation precision based on vision. In order to compensate the image jitters, the affine transformation kinematics were established for obtaining the six image motion parameters. The feature point pair detecting method was designed based on Eigen-value of the feature windows gradient matrix, and the motion parameters equation was solved using the least square method and the matching point pairs got based on the optical flow. The condition number of coefficient matrix was proposed to quantificationally analyse the effect of matching errors on parameters solving errors. Kalman filter was adopted to smooth image motion parameters. Computing cases show that more point pairs are beneficial for getting more precise motion parameters. The integrated jitters compensation software was developed with feature points detecting in subwindow. And practical experiments were conducted on two mobile robots. Results show that the compensation costing time is less than frame sample time and Kalman filter is valid for robot vision jitters compensation.

  1. Intrinsic feature-based pose measurement for imaging motion compensation

    Science.gov (United States)

    Baba, Justin S.; Goddard, Jr., James Samuel

    2014-08-19

    Systems and methods for generating motion corrected tomographic images are provided. A method includes obtaining first images of a region of interest (ROI) to be imaged and associated with a first time, where the first images are associated with different positions and orientations with respect to the ROI. The method also includes defining an active region in the each of the first images and selecting intrinsic features in each of the first images based on the active region. Second, identifying a portion of the intrinsic features temporally and spatially matching intrinsic features in corresponding ones of second images of the ROI associated with a second time prior to the first time and computing three-dimensional (3D) coordinates for the portion of the intrinsic features. Finally, the method includes computing a relative pose for the first images based on the 3D coordinates.

  2. 29 CFR 4.1b - Payment of minimum compensation based on collectively bargained wage rates and fringe benefits...

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 1 2010-07-01 2010-07-01 true Payment of minimum compensation based on collectively bargained wage rates and fringe benefits applicable to employment under predecessor contract. 4.1b Section 4... Contract Labor Standards Provisions and Procedures § 4.1b Payment of minimum compensation based on...

  3. Interactive brain shift compensation using GPU based programming

    Science.gov (United States)

    van der Steen, Sander; Noordmans, Herke Jan; Verdaasdonk, Rudolf

    2009-02-01

    Processing large images files or real-time video streams requires intense computational power. Driven by the gaming industry, the processing power of graphic process units (GPUs) has increased significantly. With the pixel shader model 4.0 the GPU can be used for image processing 10x faster than the CPU. Dedicated software was developed to deform 3D MR and CT image sets for real-time brain shift correction during navigated neurosurgery using landmarks or cortical surface traces defined by the navigation pointer. Feedback was given using orthogonal slices and an interactively raytraced 3D brain image. GPU based programming enables real-time processing of high definition image datasets and various applications can be developed in medicine, optics and image sciences.

  4. Bilateral control-based compensation for rotation in imaging in scan imaging systems

    Science.gov (United States)

    Tian, Dapeng; Wang, Yutang; Wang, Fuchao; Zhang, Yupeng

    2015-12-01

    Scan imaging systems rely on the rotation of a mirror to scan an image. The rotation in the resulting image must be compensated to prevent information loss. Satisfactory performance of an imaging system is difficult to achieve when employing the methods of mechanical transmission and unilateral tracking control, especially when the system suffers from nonlinear factors, disturbances, and dynamic uncertainties. This paper proposes a compensation method based on bilateral control derived from the field of haptic robots. A two-loop disturbance observer was designed to guarantee that the dynamic characteristics of the motor are close to those of the nominal model. The controllers were designed on the basis of the small gain theorem. Experiments were conducted for a comparison with the traditional unilateral control-based compensation. The comparison showed a reduction of 99.83% in the L2 norm of error, which validates the method. The proposed method improves the accuracy of compensation for rotation in imaging, and demonstrates that bilateral control has feasibility for application in various fields, including photogrammetry.

  5. The Quota-Based Compensation Plan in Fashion Retailing Industry under Asymmetric Information

    Directory of Open Access Journals (Sweden)

    Mingzhu Yu

    2014-01-01

    Full Text Available We study a compensation plan problem in the fashion retailing industry, which involves a risk-neutral fashion retailer and a risk-neutral salesperson, in a two-stage game framework with asymmetric information. In the first stage, the fashion retailer provides a menu of compensation plans to the salesperson who decides which plan to sign based on his superior market demand information. Confronted with the asymmetric demand information, the fashion retailer could observe market information from the salesperson's response by designing a menu of compensation plans rather than a single one to the salesperson. In the second stage, the fashion retailer then makes production decision and the salesperson determines his selling effort. We consider both adverse selection and moral hazard. We adopt the quota-based plan to derive the fashion retailer’s optimal compensation plan design and the salesperson's best response. We emphasize the impact of the quota level on the system outcomes. The results reveal that a higher quota level is disadvantageous to the fashion retailer but advantageous to the salespersons.

  6. Dosimetric studies of cadmium free alloy used in compensator based intensity modulated radiotherapy

    Science.gov (United States)

    Kaushik, Sandeep; Punia, Rajesh; Tyagi, Atul; Singh, Mann P.

    2017-10-01

    Aim of this study was to investigate dosimetric properties of cadmium free alloy which is used in compensator based intensity modulated radiotherapy (cIMRT). A mixture of lead, bismuth and tin was used to prepare the alloy whose melting point is 90-95 °C. Slabs of different thicknesses ranging from 0.71 cm to 6.14 cm were prepared. Density of alloy was measured by Archimedes' principle using water. For six megavolt (6 MV) photon beam energy transmission, linear effective attenuation coefficient (μeff), tissue phantom ratio (TPR1020), beam hardening, surface dose (Ds), percentage depth dose (PDD) and effect of scatter has been measured and analyzed for different field sizes and different thickness of compensator. Effect of extended source to detector distance (SDD) on transmissions and μeff was measured. The density of alloy was found to be 9.5456 g/cm3. At SDD of 100 cm, μeff was observed 0.4253 cm-1 for a field size of 10×10 cm 2. Calculated TPR1020 was found to be within 3% of experimental TPR1020 . It was found to be increasing with increasing thickness of compensator. Ds was found to decrease with thickness of compensator and increase with wider collimator opening due to increased scattered dose. Compensator slabs of 1 cm, 1.98 cm and 4.16 cm decreased surface dose by 4.2%, 6.1% and 9.5% respectively for a field size of 10×10 cm2 at 100 cm SDD. For small field size of 3×3 cm2 and 5×5 cm2 PDDs are increased from 3.0% to 5.5% of open beam PDDs as compensator thickness increased from 1 cm to 6.14 cm at a depth of 10 cm in water while variation in PDD is insignificant in for larger field sizes 10×10 cm2 to 20×20 cm2. A high degree of intensity modulation is essential in cIMRT and it can be achieved with this compensator material. Dosimetric properties analyzed in this study establish this alloy as a reliable, reusable, optimally dense and cost effective compensator material.

  7. Image-based motion compensation for high-resolution extremities cone-beam CT

    Science.gov (United States)

    Sisniega, A.; Stayman, J. W.; Cao, Q.; Yorkston, J.; Siewerdsen, J. H.; Zbijewski, W.

    2016-03-01

    Purpose: Cone-beam CT (CBCT) of the extremities provides high spatial resolution, but its quantitative accuracy may be challenged by involuntary sub-mm patient motion that cannot be eliminated with simple means of external immobilization. We investigate a two-step iterative motion compensation based on a multi-component metric of image sharpness. Methods: Motion is considered with respect to locally rigid motion within a particular region of interest, and the method supports application to multiple locally rigid regions. Motion is estimated by maximizing a cost function with three components: a gradient metric encouraging image sharpness, an entropy term that favors high contrast and penalizes streaks, and a penalty term encouraging smooth motion. Motion compensation involved initial coarse estimation of gross motion followed by estimation of fine-scale displacements using high resolution reconstructions. The method was evaluated in simulations with synthetic motion (1-4 mm) applied to a wrist volume obtained on a CMOS-based CBCT testbench. Structural similarity index (SSIM) quantified the agreement between motion-compensated and static data. The algorithm was also tested on a motion contaminated patient scan from dedicated extremities CBCT. Results: Excellent correction was achieved for the investigated range of displacements, indicated by good visual agreement with the static data. 10-15% improvement in SSIM was attained for 2-4 mm motions. The compensation was robust against increasing motion (4% decrease in SSIM across the investigated range, compared to 14% with no compensation). Consistent performance was achieved across a range of noise levels. Significant mitigation of artifacts was shown in patient data. Conclusion: The results indicate feasibility of image-based motion correction in extremities CBCT without the need for a priori motion models, external trackers, or fiducials.

  8. Nonlinear adaptive control based on fuzzy sliding mode technique and fuzzy-based compensator.

    Science.gov (United States)

    Nguyen, Sy Dzung; Vo, Hoang Duy; Seo, Tae-Il

    2017-09-01

    It is difficult to efficiently control nonlinear systems in the presence of uncertainty and disturbance (UAD). One of the main reasons derives from the negative impact of the unknown features of UAD as well as the response delay of the control system on the accuracy rate in the real time of the control signal. In order to deal with this, we propose a new controller named CO-FSMC for a class of nonlinear control systems subjected to UAD, which is constituted of a fuzzy sliding mode controller (FSMC) and a fuzzy-based compensator (CO). Firstly, the FSMC and CO are designed independently, and then an adaptive fuzzy structure is discovered to combine them. Solutions for avoiding the singular cases of the fuzzy-based function approximation and reducing the calculating cost are proposed. Based on the solutions, fuzzy sliding mode technique, lumped disturbance observer and Lyapunov stability analysis, a closed-loop adaptive control law is formulated. Simulations along with a real application based on a semi-active train-car suspension are performed to fully evaluate the method. The obtained results reflected that vibration of the chassis mass is insensitive to UAD. Compared with the other fuzzy sliding mode control strategies, the CO-FSMC can provide the best control ability to reduce unwanted vibrations. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  9. Spatio-temporal Compensation Based Object Detection for Video Surveillance Systems

    Institute of Scientific and Technical Information of China (English)

    LI Ren-jie; YU Song-yu; XIONG Hong-kai

    2008-01-01

    Moving object detection in video surveillance is an important step.This paper addresses an automatic object detection algorithm based on spatio-temporal compensation for video surveillance.Temporal difference of the pairs of two frames with a k-frame distance is utilized to obtain coarse object masks.Usually,object regions in these coarse masks have discontinuous boundaries and some holes.Region growing with the distance constraint is proposed to compensate these coarse object regions in spatial domain,followed by filling holes.The added distance constraint can prevent object regions from growing infinitely.The proposed fining holes method is simple and effective.To solve the temporarily stopping problem of moving objects,temporal compensation is proposed to compensate the object mask by utilizing temporal coherence of moving objects in temporal domain.The proposed detection algorithm can extract moving objects as completely as possible.Experimental results have successfully demonstrated the validity of the proposed algorithm.

  10. 1H NMR-based serum metabolic profiling in compensated and decompensated cirrhosis

    Institute of Scientific and Technical Information of China (English)

    Su-Wen Qi; Zhi-Guang Tu; Wu-Jian Peng; Lin-Xian Wang; Xin Ou-Yang; An-Ji Cai; Yong Dai

    2012-01-01

    AIM: To study the metabolic profiling of serum samples from compensated and decompensated cirrhosis patients.METHODS: A pilot metabolic profiling study was conducted using three groups: compensated cirrhosis patients (n = 30), decompensated cirrhosis patients (n = 30) and healthy controls (n = 30). A 1H nuclear magnetic resonance (NMR)-based metabonomics approach was used to obtain the serum metabolic profiles of the samples. The acquired data were processed by multivariate principal component analysis and orthogonal partial least-squares discriminant analysis (OPLS-DA). RESULTS: The OPLS-DA model was capable of distinguishing between decompensated and compensated cirrhosis patients, with an R2Y of 0.784 and a Q2Y of 0.598. Twelve metabolites, such as pyruvate, phenylalanine and succinate, were identified as the most influential factors for the difference between the two groups. The validation of the diagnosis prediction showed that the accuracy of the OPLSDA model was 85% (17/20). CONCLUSION: 1H NMR spectra combined with pattern recognition analysis techniques offer a new way to diagnose compensated and decompensated cirrhosis in the future.

  11. Automatic DGD and GVD compensation at 640 Gb/s based on scalar radio-frequency spectrum measurement

    DEFF Research Database (Denmark)

    Paquot, Yvan; Schröder, Jochen; Palushani, Evarist;

    2013-01-01

    of separate GVD and DGD compensators using an impairment monitor based on an integrated all-optical radio-frequency (RF) spectrum analyzer. We show that low-bandwidth measurement of only a single tone in the RF spectrum is sufficient for automatic compensation for multiple degrees of freedom using...

  12. Attenuation compensation of GPR signal based on generalized S-transform

    Science.gov (United States)

    Hu, Shufan; Zhao, Yonghui; Qin, Tan; An, Cong

    2017-04-01

    Ground penetrating radar (GPR), as a nondestructive technique, has been widely used in civil engineering. Due to the complexity of the engineering conditions and attenuation of the GPR signal with depth, the radargram contained deep information usually shows a low resolution and S/N ratio. It might be one of the most difficult problems to GPR data interpretation, which limits the further application of the GPR method in civil engineering. The traditional way, such as a manual or automatic gain technique, was commonly used to enhance the weak GPR signal of deep target. However, due to the non-stationary of GPR signal, only the energy compensation in time or frequency domain may be not appropriate while using the manual or automatic gain methods. In this sense, neither the automatic gain compensation nor the other gain method seem likely difficult to obtain better results. In fact, it's not reasonable to separate the information in time and frequency domain from GPR data. The S-transform is a time-frequency analysis technique, which makes it possible for analyzing the GPR signal in time and frequency domain simultaneously. In addition, use S-transform to GPR data can preserve the original information in a wide frequency range. Here, we proposed a generalized S-transform based on exponential function and used it to the attenuation compensation of GPR signal. Firstly, the GPR data were transform to time-frequency domain using generalized S-transform trace by trace. Then the high-frequency component will be weighted at each time sample according to the attenuation ratio of low-frequency component. In this way the spectrum difference of each frequency component between late and early sampling time have the same ratio factor, which greatly compensates the attenuation of high-frequency component. Finally, the well compensated GPR data were obtained by inverse S-transform. Synthetic and real GPR data were used to verify the effectiveness and robustness of the proposed

  13. Coordination mechanism of SaaS service supply chain: Based on compensation contracts

    Directory of Open Access Journals (Sweden)

    Yanli Guo

    2013-09-01

    Full Text Available Purpose: The purpose of this paper is to build new contracts theories of SaaS service supply chain. Software as a Service (SaaS has become a hot topic in this industry . Compared with traditional manufacturing supply chain and general service supply chain, the new IT service supply chain which based on SaaS has characteristics of both service and IT. And SaaS is completely different from traditional software package model. Therefore the classic contracts, which be widely used in traditional manufacturing supply chain, can’t be directly applied in SaaS service supply chain. The necessary way of IT services developing is to study the SaaS service supply chain combining with characteristics of SaaS. Therefore, It focuses on the coordination of SaaS service supply chain. Design/methodology/approach: It tries to answer the following question: how do the ISV motivate SaaS operators to improve the service level through effective contracts mechanism under conditions of asymmetric information. In order to answer these questions, this paper does some researches including: Under the conditions of information asymmetry, supposing the service level (is related to the degree of effort of SaaS operator was private information, we construct model of compensation contract, i.e., to motivate SaaS operator to improve service level through transfer payments of compensation price. Findings and Originality/value: The study finds out that when ISV get to “positive feedback”, instead of the traditional market equilibrium, compensation contract (linear can coordinate satisfactorily the SaaS service supply chain. In the point of “positive feedback”, the marginal revenue equals the marginal cost, but it is not the equilibrium of ISV’profit-maximization. Research limitations/implications: There are some limitations in this research. In the linear compensation contracts, the compensation price is fixed value. If in the contract, we can create a change value

  14. An uncooled microbolometer focal plane array using heating based resistance nonuniformity compensation

    Science.gov (United States)

    Tepegoz, Murat; Oguz, Alp; Toprak, Alperen; Senveli, S. Ufuk; Canga, Eren; Tanrikulu, M. Yusuf; Akin, Tayfun

    2012-06-01

    This paper presents the performance evaluation of a unique method called heating based resistance nonuniformity compensation (HB-RNUC). The HB-RNUC method utilizes a configurable bias heating duration for each pixel in order to minimize the readout integrated circuit (ROIC) output voltage distribution range. The outputs of each individual pixel in a resistive type microbolometer differ from each other by a certain amount due to the resistance non-uniformity throughout the focal plane array (FPA), which is an inevitable result of the microfabrication process. This output distribution consumes a considerable portion of the available voltage headroom of the ROIC unless compensated properly. The conventional compensation method is using on-chip DACs to apply specific bias voltages to each pixel such that the output distribution is confined around a certain point. However, on-chip DACs typically occupy large silicon area, increase the output noise, and consume high power. The HB-RNUC method proposes modifying the resistances of the pixels instead of the bias voltages, and this task can be accomplished by very simple circuit blocks. The simplicity of the required blocks allows utilizing a low power, low noise, and high resolution resistance nonuniformity compensation operation. A 9-bit HB-RNUC structure has been designed, fabricated, and tested on a 384x288 microbolometer FPA ROIC on which 35μm pixel size detectors are monolithically implemented, in order to evaluate its performance. The compensation operation reduces the standard deviation of the ROIC output distribution from 470 mV to 9 mV under the same readout gain and bias settings. The analog heating channels of the HB-RNUC block dissipate around 4.1 mW electrical power in this condition, and the increase in the output noise due to these blocks is lower than 10%.

  15. Sensorless Control Technology for PMSG base on the Dead-time Compensation voltage

    Directory of Open Access Journals (Sweden)

    Yang Li-yong

    2015-01-01

    Full Text Available In order to improve the speed sensorless-control system of PMSG in low speed performance, this paper introduces a novel Dead-time compensation control method .Mathematical model is established according to the Dead-zone of the influence of the voltage source type inverter output voltage. At the same time, the given value of current regulator output voltage has been fixed based on the established model. Then the stator voltage after compensationed is applied to the flux estimation, which improves the performance of flux estimation. Finally, the position and speed of the rotor is estimated based on Back-Electromotive Force, which has Simple algorithm and good robustness. In order to verify the correctness of theoretical analysis, the experiment was done according to the new control method. The results proved the correctness and feasibility of this control method.

  16. The ecological damage compensation for hydropower development based on trade-offs in river ecosystem services

    Science.gov (United States)

    Yu, Bing

    2017-05-01

    Hydropower development is a kind of trade-offs in river ecosystem services, while increasing provision services but reduce some regulation or supporting services. However, some ecosystem services we lost are difficult to recover and thus affect the regulated river and riparian ecosystems inevitably. In this context, an ecological compensation framework for damaged river in hydropower development was proposed based on the trade-off in river ecosystem services. And the accounting system for affected rivers was established based on river eco-service alteration, for the hydropower services cannot replace the lost services. Using the ecosystem services valuation methods, the trade-offs of river ecosystem services were quantified and illustrated by some hydropower projects in Lancang River, Yalung River and Min Chiang in China. According to the survey data, the annual compensation standard of per unit installed capacity in above cases may range from 27 to 206 RMB Yuan.

  17. Synthetic aperture sonar movement compensation algorithm based on time-delay and phase estimation

    Institute of Scientific and Technical Information of China (English)

    JIANG Nan; SUN Dajun; TIAN Tan

    2003-01-01

    The effects of movement errors on imaging results of synthetic aperture sonar andthe necessity of movement compensation are discussed. Based on analyzing so-called displacedphase center algorithm, an improved algorithm is proposed. In this method, the time delayis estimated firstly, then the phase is estimated for the residual error, so that the range ofmovement error suited to the algorithm is extended to some extent. Some simulation resultson computer and experimental results in the test tank using the proposed algorithm are givenas well.

  18. Automatic illumination compensation device based on a photoelectrochemical biofuel cell driven by visible light

    Science.gov (United States)

    Yu, You; Han, Yanchao; Xu, Miao; Zhang, Lingling; Dong, Shaojun

    2016-04-01

    Inverted illumination compensation is important in energy-saving projects, artificial photosynthesis and some forms of agriculture, such as hydroponics. However, only a few illumination adjustments based on self-powered biodetectors that quantitatively detect the intensity of visible light have been reported. We constructed an automatic illumination compensation device based on a photoelectrochemical biofuel cell (PBFC) driven by visible light. The PBFC consisted of a glucose dehydrogenase modified bioanode and a p-type semiconductor cuprous oxide photocathode. The PBFC had a high power output of 161.4 μW cm-2 and an open circuit potential that responded rapidly to visible light. It adjusted the amount of illumination inversely irrespective of how the external illumination was changed. This rational design of utilizing PBFCs provides new insights into automatic light adjustable devices and may be of benefit to intelligent applications.Inverted illumination compensation is important in energy-saving projects, artificial photosynthesis and some forms of agriculture, such as hydroponics. However, only a few illumination adjustments based on self-powered biodetectors that quantitatively detect the intensity of visible light have been reported. We constructed an automatic illumination compensation device based on a photoelectrochemical biofuel cell (PBFC) driven by visible light. The PBFC consisted of a glucose dehydrogenase modified bioanode and a p-type semiconductor cuprous oxide photocathode. The PBFC had a high power output of 161.4 μW cm-2 and an open circuit potential that responded rapidly to visible light. It adjusted the amount of illumination inversely irrespective of how the external illumination was changed. This rational design of utilizing PBFCs provides new insights into automatic light adjustable devices and may be of benefit to intelligent applications. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr00759g

  19. The Value and Incentives of Option-based Compensation in Danish Listed Companies

    DEFF Research Database (Denmark)

    Bechmann, Ken; Jørgensen, Peter Løchte

    2003-01-01

    contracts issuedby the complete sample of Danish companies listed on the Copenhagen Stock Exchange.A newly constructed database containing all publicly available information on details of DanishOBC contracts allows us to present, for example, results regarding contract values at an aggregated aswell...... as at firm, personnel group, and individual level. The paper also contains a section which discussesand presents evidence on the incentive effects provided by the option-based compensation contractsadopted by Danish listed companies....

  20. Measure of Watershed Ecological Compensation Standard Based on WTP and WTA

    OpenAIRE

    Xu, Dawei; RONG, Jinfang; Yang, Na; Zhang, Wen

    2013-01-01

    In this paper, Liao River Basin was taken as the research object and field surveys were conducted in Fudedian, the source of Liao river mainstream and Panjin, the estuary of Liao River. Through the questionnaires, the willingness to pay (WTP) and willingness to accept (WTA) of the residents in Liao River Basin were analyzed. Then based on analysis of the existing ecological compensation standard measuring methods, the WTP and WTA using contingent valuation method (CVM) were measured and analy...

  1. Dual objective active suspension system based on a novel nonlinear disturbance compensator

    Science.gov (United States)

    Deshpande, Vaijayanti S.; Shendge, P. D.; Phadke, S. B.

    2016-09-01

    This paper proposes an active suspension system to fulfil the dual objective of improving ride comfort while trying to keep the suspension deflection within the limits of the rattle space. The scheme is based on a novel nonlinear disturbance compensator which employs a nonlinear function of the suspension deflection. The scheme is analysed and validated by simulation and experimentation on a laboratory setup. The performance is compared with a passive suspension system for a variety of road profiles.

  2. Feasibility of wear compensation in micro EDM milling based on discharge counting and discharge population characterization

    DEFF Research Database (Denmark)

    Bissacco, Giuliano; Hansen, Hans Nørgaard; Tristo, G.

    2011-01-01

    This paper investigates the applicability of real time wear compensation in micro EDM milling based on discharge counting and discharge population characterization. Experiments were performed involving discharge counting and tool electrode wear measurement in a wide range of process parameters...... settings involving different current pulse shapes. A strong correlation is found between average discharge energy of the populations and wear and material removal per discharge. A validation was carried out showing the feasibility of the proposed approach....

  3. Fault Diagnosis for Compensating Capacitors of Jointless Track Circuit Based on Dynamic Time Warping

    Directory of Open Access Journals (Sweden)

    Wei Dong

    2014-01-01

    Full Text Available Aiming at the problem of online fault diagnosis for compensating capacitors of jointless track circuit, a dynamic time warping (DTW based diagnosis method is proposed in this paper. Different from the existing related works, this method only uses the ground indoor monitoring signals of track circuit to locate the faulty compensating capacitor, not depending on the shunt current of inspection train, which is an indispensable condition for existing methods. So, it can be used for online diagnosis of compensating capacitor, which has not yet been realized by existing methods. To overcome the key problem that track circuit cannot obtain the precise position of the train, the DTW method is used for the first time in this situation to recover the function relationship between receiver’s peak voltage and shunt position. The necessity, thinking, and procedure of the method are described in detail. Besides the classical DTW based method, two improved methods for improving classification quality and reducing computation complexity are proposed. Finally, the diagnosis experiments based on the simulation model of track circuit show the effectiveness of the proposed methods.

  4. Multichannel loudness compensation method based on segmented sound pressure level for digital hearing aids

    Science.gov (United States)

    Liang, Ruiyu; Xi, Ji; Bao, Yongqiang

    2017-07-01

    To improve the performance of gain compensation based on three-segment sound pressure level (SPL) in hearing aids, an improved multichannel loudness compensation method based on eight-segment SPL was proposed. Firstly, the uniform cosine modulated filter bank was designed. Then, the adjacent channels which have low or gradual slopes were adaptively merged to obtain the corresponding non-uniform cosine modulated filter according to the audiogram of hearing impaired persons. Secondly, the input speech was decomposed into sub-band signals and the SPL of every sub-band signal was computed. Meanwhile, the audible SPL range from 0 dB SPL to 120 dB SPL was equally divided into eight segments. Based on these segments, a different prescription formula was designed to compute more detailed gain to compensate according to the audiogram and the computed SPL. Finally, the enhanced signal was synthesized. Objective experiments showed the decomposed signals after cosine modulated filter bank have little distortion. Objective experiments showed that the hearing aids speech perception index (HASPI) and hearing aids speech quality index (HASQI) increased 0.083 and 0.082 on average, respectively. Subjective experiments showed the proposed algorithm can effectively improve the speech recognition of six hearing impaired persons.

  5. A novel compensation-based recurrent fuzzy neural network and its learning algorithm

    Institute of Scientific and Technical Information of China (English)

    WU Bo; WU Ke; LU JianHong

    2009-01-01

    Based on detailed atudy on aeveral kinds of fuzzy neural networks, we propose a novel compensation. based recurrent fuzzy neural network (CRFNN) by adding recurrent element and compensatory element to the conventional fuzzy neural network. Then, we propose a sequential learning method for the structure Identification of the CRFNN In order to confirm the fuzzy rules and their correlaUve parameters effectively. Furthermore, we Improve the BP algorithm based on the characteristics of the proposed CRFNN to train the network. By modeling the typical nonlinear systems, we draw the conclusion that the proposed CRFNN has excellent dynamic response and strong learning ability.

  6. Analysis of marine ecological compensation for environmental risk caused by chemical spill based on game theory

    Institute of Scientific and Technical Information of China (English)

    Zhang Jiwei; Yang Zhifeng; Huang Xinyu

    2009-01-01

    The problem of marine environmental risk is ultimately the result of game theory between the marine environmental managers and the enterprise of potential environmental risk.This paper analyzes the internal economic relationship that whether the "protection" policy is applied between the protection action of marine environmental managers and the chemical enterprise, The result shows that the key factor whether the enterprise adopt the "protection" policy or not is the amount of penalty and the government's cost of execution, and the compulsive ecological compensation is obligatory from the angle of stimulating the enterprise of canontcal action and adopting the "protection" policy.To build the ecological compensation mechanism based on the environmental risk will effectively improve the level of management in sea area and decrease the probability of chemical spill.

  7. Monte Carlo-based Noise Compensation in Coil Intensity Corrected Endorectal MRI

    CERN Document Server

    Lui, Dorothy; Haider, Masoom; Wong, Alexander

    2015-01-01

    Background: Prostate cancer is one of the most common forms of cancer found in males making early diagnosis important. Magnetic resonance imaging (MRI) has been useful in visualizing and localizing tumor candidates and with the use of endorectal coils (ERC), the signal-to-noise ratio (SNR) can be improved. The coils introduce intensity inhomogeneities and the surface coil intensity correction built into MRI scanners is used to reduce these inhomogeneities. However, the correction typically performed at the MRI scanner level leads to noise amplification and noise level variations. Methods: In this study, we introduce a new Monte Carlo-based noise compensation approach for coil intensity corrected endorectal MRI which allows for effective noise compensation and preservation of details within the prostate. The approach accounts for the ERC SNR profile via a spatially-adaptive noise model for correcting non-stationary noise variations. Such a method is useful particularly for improving the image quality of coil i...

  8. The Improved Kriging Interpolation Algorithm for Local Underwater Terrain Based on Fractal Compensation

    Directory of Open Access Journals (Sweden)

    Pengyun Chen

    2014-01-01

    Full Text Available The interpolation-reconstruction of local underwater terrain using the underwater digital terrain map (UDTM is an important step for building an underwater terrain matching unit and directly affects the accuracy of underwater terrain matching navigation. The Kriging method is often used in terrain interpolation, but, with this method, the local terrain features are often lost. Therefore, the accuracy cannot meet the requirements of practical application. Analysis of the geographical features is performed on the basis of the randomness and self-similarity of underwater terrain. We extract the fractal features of local underwater terrain with the fractal Brownian motion model, compensating for the possible errors of the Kriging method with fractal theory. We then put forward an improved Kriging interpolation method based on this fractal compensation. Interpolation-reconstruction tests show that the method can simulate the real underwater terrain features well and that it has good usability.

  9. A novel input-parasitic compensation technique for a nanopore-based CMOS DNA detection sensor

    Science.gov (United States)

    Kim, Jungsuk

    2016-12-01

    This paper presents a novel input-parasitic compensation (IPC) technique for a nanopore-based complementary metal-oxide-semiconductor (CMOS) DNA detection sensor. A resistive-feedback transimpedance amplifier is typically adopted as the headstage of a DNA detection sensor to amplify the minute ionic currents generated from a nanopore and convert them to a readable voltage range for digitization. But, parasitic capacitances arising from the headstage input and the nanopore often cause headstage saturation during nanopore sensing, thereby resulting in significant DNA data loss. To compensate for the unwanted saturation, in this work, we propose an area-efficient and automated IPC technique, customized for a low-noise DNA detection sensor, fabricated using a 0.35- μm CMOS process; we demonstrated this prototype in a benchtop test using an α-hemolysin ( α-HL) protein nanopore.

  10. Dynamic Consensus Algorithm based Distributed Voltage Harmonic Compensation in Islanded Microgrids

    DEFF Research Database (Denmark)

    Meng, Lexuan; Tang, Fen; Firoozabadi, Mehdi Savaghebi

    2015-01-01

    In islanded microgrids, the existence of nonlinear electric loads may cause voltage distortion and affect the performance of power quality sensitive equipment. Thanks to the prevalent utilization of interfacing power electronic devices and information/communication technologies, distributed...... generators can be employed as compensators to enhance the power quality on consumer side. However, conventional centralized control is facing obstacles because of the distributed fashion of generation and consumption. Accordingly, this paper proposes a consensus algorithm based distributed hierarchical...... control to realize voltage harmonic compensation and accurate current sharing in multi-bus islanded microgrids. Low order harmonic components are considered as examples in this paper. Harmonic current sharing is also realized among distributed generators by applying the proposed methods. Plug...

  11. QFT control based on zero phase error compensation for flight simulator

    Institute of Scientific and Technical Information of China (English)

    Liu Jinkun; He Yuzhu

    2007-01-01

    To improve the robustness of high-precision servo systems, quantitative feedback theory (QFT) which aims to achieve a desired robust design over a specified region of plant uncertainty is proposed. The robust design problem can be solved using QFT but it fails to guarantee a high precision tracking. This problem is solved by a robust digital QFT control scheme based on zero phase error (ZPE) feed forward compensation. This scheme consists of two parts: a QFr controller in the closed-loop system and a ZPE feed-forward compensator. Digital QFT controller is designed to overcome the uncertainties in the system. Digital ZPE feed forward controller is used to improve the tracking precision. Simulation and real-time examples for flight simulator servo system indicate that this control scheme can guarantee both high robust performance and high position tracking precision.

  12. A Compensation Algorithm Based on RSPWVD-Hough Transform for Doppler Expansion in Passive Radar

    Directory of Open Access Journals (Sweden)

    Guan Xin

    2013-12-01

    Full Text Available For passive radar, long integration time is used to achieve high processing gain to detect weak target. But range migration and Doppler expansion may occur for high-speed targets. Keystone transform can be used to rectify range migration introduced by radial-speed. But tangential-speed may still lead to Doppler expansion, which entails a loss of integration gain. In this paper, signal model is presented to analyze the reason for Doppler expansion. Then, a Doppler expansion compensation method is introduced based on RSPWVD-Hough transform for multi-target scenario. Simulation results show that the proposed method can compensate the energy loss caused by Doppler expansion for multi-target scene, and it achieves good performance. The proposed method is also effective for weak targets, which means it can improve the detection ability of weak target in passive radar systems.

  13. A customizable multi-channel loudness compensation method based on WDRC for digital hearing aids

    Science.gov (United States)

    Hu, Jiebin; Wang, Mingjiang; Ma, Min

    2017-08-01

    Loudness compensation is the most significant signal processing algorithm in digital hearing aids at present. An algorithm of multi-channel loudness compensation for embedded system has been put forward in this paper. The number of channels is customizable in this algorithm. The algorithm can set different number and different width of channels for each patient based on frequency domain wide dynamic range compression. First, according to the requirement of patient to divide the frequency domain into multiple unequal frequency bands. And then calculate the gain of each channel according to the input-output curve of sound pressure level. Finally, the time-domain impulse response of gain is computed from Mel filter banks. It is used in conjunction with speech enhancement processing in hearing aids. Simulation results show that the algorithm can effectively enhance the loudness for different frequencies.

  14. Loss compensation in metamaterials through embedding of active transistor based negative differential resistance circuits.

    Science.gov (United States)

    Xu, Wangren; Padilla, Willie J; Sonkusale, Sameer

    2012-09-24

    Dielectric and ohmic losses in metamaterials are known to limit their practical use. In this paper, an all-electronic approach for loss compensation in metamaterials is presented. Each unit cell of the meta-material is embedded with a cross-coupled transistor pair based negative differential resistance circuit to cancel these losses. Design, simulation and experimental results for Split Ring Resonator (SRR) metamaterials with and without loss compensation are presented. Results indicate that the quality factor (Q) of the SRR improves by over 400% at 1.6 GHz, showing the effectiveness of the approach. The proposed technique is scalable over a broad frequency range and is limited only by the maximum operating frequency of transistors, which is reaching terahertz in today's semiconductor technologies.

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

    Directory of Open Access Journals (Sweden)

    Gang Chen

    2015-07-01

    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.

  16. Amplitude spectrum compensation and phase spectrum correction of seismic data based on the generalized S transform

    Institute of Scientific and Technical Information of China (English)

    Zhou Huai-Lai; Wang Jun; Wang Ming-Chun; Shen Ming-Cheng; Zhang Xin-Kun; Liang Ping

    2014-01-01

    We propose a method for the compensation and phase correction of the ampli-tude spectrum based on the generalized S transform. The compensation of the amplitude spectrum within a reliable frequency range of the seismic record is performed in the S do-main to restore the amplitude spectrum of reflection. We use spectral simulation methods to fit the time-dependent amplitude spectrum and compensate for the amplitude attenuation owing to absorption. We use phase scanning to select the time-, space-, and frequency-dependent phases correction based on the parsimony criterion and eliminate the residual phase effect of the wavelet in the S domain. The method does not directly calculate the Q value;thus, it can be applied to the case of variable Q. The comparison of the theory model and field data verify that the proposed method can recover the amplitude spectrum of the strata reflectivity, while eliminating the effect of the residual phase of the wavelet. Thus, the wavelet approaches the zero-phase wavelet and, the seismic resolution is improved.

  17. Compensation benefits in a population-based cohort of men and women on long-term disability after musculoskeletal injuries: costs, course, predictors.

    Science.gov (United States)

    Lederer, Valérie; Rivard, Michèle

    2014-11-01

    The aim of this study is to assess costs, duration and predictors of prolonged compensation benefits by gender in a population characterised by long-term compensation benefits for traumatic or non-traumatic musculoskeletal injuries (MSIs). This study examined 3 years of data from a register-based provincial cohort including all new allowed long-term claims (≥3 months of wage replacement benefits) related to neck/shoulder/back/trunk/upper-limb MSIs in Quebec, Canada, from 2001 to 2003 (13,073 men and 9032 women). Main outcomes were compensation duration and costs. Analyses were carried out separately for men and women to investigate gender differences. An extended Cox model with Heaviside functions of time was used to account for covariates with time-varying effects. Male workers experienced a longer compensation benefit duration and higher median costs. At the end of follow-up, 3 years postinjury, 12.3% of men and 7.3% of women were still receiving compensation benefits. Effects of certain predictors (e.g., income, injury site or industry) differed markedly between men and women. Age and claim history had time-varying effects in the men's and women's models, respectively. Knowing costs, duration and predictors of long-term compensation claims by gender can help employers, decision makers and rehabilitation specialists to identify at-risk workers and industries to engage them in early intervention and prevention programmes. Tailoring parts of long-term disability prevention and management efforts to men's and women's specific needs, barriers and vulnerable subgroups, could reduce time on benefits among both male and female long-term claimants. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  18. Science Letters:A new quantitative model of ecological compensation based on ecosystem capital in Zhejiang Province, China

    Institute of Scientific and Technical Information of China (English)

    Yan JIN; Jing-feng HUANG; Dai-liang PENG

    2009-01-01

    Ecological compensation is becoming one of key and multidiscipline issues in the field of resources and environ-mental management. Considering the change relation between gross domestic product (GDP) and ecological capital (EC) based on remote sensing estimation, we construct a new quantitative estimate model for ecological compensation, using county as study unit,and determine standard value so as to evaluate ecological compensation from 2001 to 2004 in Zhejiang Province, China. Spatial differences of the ecological compensation were significant among all the counties or districts. This model fills up the gap in the field of quantitative evaluation of regional ecological compensation and provides a feasible way to reconcile the conflicts among benefits in the economic, social, and ecological sectors.

  19. 40-Gbit/s Operation of Ultracompact Photodetector-Integrated Dispersion Compensator Based on One-Dimensional Photonic Crystals

    Science.gov (United States)

    Sagawa, Misuzu; Goto, Shigeo; Hosomi, Kazuhiko; Sugawara, Toshiki; Katsuyama, Toshio; Arakawa, Yasuhiko

    2008-08-01

    Utilizing large optical group-velocity dependence on wavelength without polarization-mode dependence, we have developed an ultracompact dispersion compensator based on multiple one-dimensional coupled-defect-type photonic crystals. The photonic crystal of the compensator, designed for a 1.55-µm optical communication system, consists of a multilayer thin-film structure and defect layers. The thin-film structure is substrate-free, which enables the compensator to be small, that is, a 1.4-mm-edge cube. To obtain a large group-velocity difference, 60 substrate-free films were stacked to form the compensator. The passband of the compensator is 2 nm, and the group-delay time difference within the band is more than 100 ps. A dispersion-compensator module integrated with a photodetector was fabricated. A 40-Gbit/s non-return-to-zero optical-transmission experiment was carried out with the compensator, demonstrating dispersion-compensation operation over a 10-km standard single-mode fiber, the dispersion of which corresponds to 170 ps/nm.

  20. Optimizing Fuzzy Rule Base for Illumination Compensation in Face Recognition using Genetic Algorithms

    Directory of Open Access Journals (Sweden)

    Bima Sena Bayu Dewantara

    2014-12-01

    Full Text Available Fuzzy rule optimization is a challenging step in the development of a fuzzy model. A simple two inputs fuzzy model may have thousands of combination of fuzzy rules when it deals with large number of input variations. Intuitively and trial‐error determination of fuzzy rule is very difficult. This paper addresses the problem of optimizing Fuzzy rule using Genetic Algorithm to compensate illumination effect in face recognition. Since uneven illumination contributes negative effects to the performance of face recognition, those effects must be compensated. We have developed a novel algorithmbased on a reflectance model to compensate the effect of illumination for human face recognition. We build a pair of model from a single image and reason those modelsusing Fuzzy.Fuzzy rule, then, is optimized using Genetic Algorithm. This approachspendsless computation cost by still keepinga high performance. Based on the experimental result, we can show that our algorithm is feasiblefor recognizing desired person under variable lighting conditions with faster computation time. Keywords: Face recognition, harsh illumination, reflectance model, fuzzy, genetic algorithm

  1. Signal Construction-Based Dispersion Compensation of Lamb Waves Considering Signal Waveform and Amplitude Spectrum Preservation

    Directory of Open Access Journals (Sweden)

    Jian Cai

    2016-12-01

    Full Text Available The results of Lamb wave identification for the aerospace structures could be easily affected by the nonlinear-dispersion characteristics. In this paper, dispersion compensation of Lamb waves is of particular concern. Compared with the similar research works on the traditional signal domain transform methods, this study is based on signal construction from the viewpoint of nonlinear wavenumber linearization. Two compensation methods of linearly-dispersive signal construction (LDSC and non-dispersive signal construction (NDSC are proposed. Furthermore, to improve the compensation effect, the influence of the signal construction process on the other crucial signal properties, including the signal waveform and amplitude spectrum, is considered during the investigation. The linear-dispersion and non-dispersion effects are firstly analyzed. Then, after the basic signal construction principle is explored, the numerical realization of LDSC and NDSC is discussed, in which the signal waveform and amplitude spectrum preservation is especially regarded. Subsequently, associated with the delay-and-sum algorithm, LDSC or NDSC is employed for high spatial resolution damage imaging, so that the adjacent multi-damage or quantitative imaging capacity of Lamb waves can be strengthened. To verify the proposed signal construction and damage imaging methods, the experimental and numerical validation is finally arranged on the aluminum plates.

  2. Signal Construction-Based Dispersion Compensation of Lamb Waves Considering Signal Waveform and Amplitude Spectrum Preservation.

    Science.gov (United States)

    Cai, Jian; Yuan, Shenfang; Wang, Tongguang

    2016-12-23

    The results of Lamb wave identification for the aerospace structures could be easily affected by the nonlinear-dispersion characteristics. In this paper, dispersion compensation of Lamb waves is of particular concern. Compared with the similar research works on the traditional signal domain transform methods, this study is based on signal construction from the viewpoint of nonlinear wavenumber linearization. Two compensation methods of linearly-dispersive signal construction (LDSC) and non-dispersive signal construction (NDSC) are proposed. Furthermore, to improve the compensation effect, the influence of the signal construction process on the other crucial signal properties, including the signal waveform and amplitude spectrum, is considered during the investigation. The linear-dispersion and non-dispersion effects are firstly analyzed. Then, after the basic signal construction principle is explored, the numerical realization of LDSC and NDSC is discussed, in which the signal waveform and amplitude spectrum preservation is especially regarded. Subsequently, associated with the delay-and-sum algorithm, LDSC or NDSC is employed for high spatial resolution damage imaging, so that the adjacent multi-damage or quantitative imaging capacity of Lamb waves can be strengthened. To verify the proposed signal construction and damage imaging methods, the experimental and numerical validation is finally arranged on the aluminum plates.

  3. [Base-rate estimates for negative response bias in a workers' compensation claim sample].

    Science.gov (United States)

    Merten, T; Krahi, G; Krahl, C; Freytag, H W

    2010-09-01

    Against the background of a growing interest in symptom validity assessment in European countries, new data on base rates of negative response bias is presented. A retrospective data analysis of forensic psychological evaluations was performed based on 398 patients with workers' compensation claims. 48 percent of all patients scored below cut-off in at least one symptom validity test (SVT) indicating possible negative response bias. However, different SVTs appear to have differing potential to identify negative response bias. The data point at the necessity to use modern methods to check data validity in civil forensic contexts.

  4. Zero phase error control based on neural compensation for flight simulator servo system

    Institute of Scientific and Technical Information of China (English)

    Liu Jinkun; He Peng; Er Lianjie

    2006-01-01

    Using the future desired input value, zero phase error controller enables the overall system's frequency response exhibit zero phase shift for all frequencies and a small gain error at low frequency range, and based on this, a new algorithm is presented to design the feedforward controller. However, zero phase error controller is only suitable for certain linear system. To reduce the tracking error and improve robustness, the design of the proposed feedforward controller uses a neural compensation based on diagonal recurrent neural network. Simulation and real-time control results for flight simulator servo system show the effectiveness of the proposed approach.

  5. EBT GAFCHROMIC{sup TM} film dosimetry in compensator-based intensity modulated radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Vaezzadeh, Seyedali [Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Allahverdi, Mahmoud, E-mail: alahverdi@sina.tums.ac.ir [Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Department of Radiotherapy—Oncology, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Nedaie, Hasan A. [Department of Radiotherapy—Oncology, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Ay, Mohammadreza [Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Research Center for Science and Technology in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Shirazi, Alireza; Yarahmadi, Mehran [Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2013-07-01

    The electron benefit transfer (EBT) GAFCHROMIC films possess a number of features making them appropriate for high-quality dosimetry in intensity-modulated radiation therapy (IMRT). Compensators to deliver IMRT are known to change the beam-energy spectrum as well as to produce scattered photons and to contaminate electrons; therefore, the accuracy and validity of EBT-film dosimetry in compensator-based IMRT should be investigated. Percentage-depth doses and lateral-beam profiles were measured using EBT films in perpendicular orientation with respect to 6 and 18 MV photon beam energies for: (1) different thicknesses of cerrobend slab (open, 1.0, 2.0, 4.0, and 6.0 cm), field sizes (5×5, 10×10, and 20×20 cm{sup 2}), and measurement depths (D{sub max}, 5.0 and 10.0 cm); and (2) step-wedged compensator in a solid phantom. To verify results, same measurements were implemented using a 0.125 cm{sup 3} ionization chamber in a water phantom and also in Monte Carlo simulations using the Monte Carlo N-particle radiation transport computer code. The mean energy of photons was increased due to beam hardening in comparison with open fields at both 6 and 18 MV energies. For a 20×20 cm{sup 2} field size of a 6 MV photon beam and a 6.0 cm thick block, the surface dose decreased by about 12% and percentage-depth doses increased up to 3% at 30.0 cm depth, due to the beam-hardening effect induced by the block. In contrast, at 18 MV, the surface dose increased by about 8% and depth dose reduced by 3% at 30.0 cm depth. The penumbral widths (80% to 20%) increase with block thickness, field size, and beam energy. The EBT film results were in good agreement with the ionization chamber dose profiles and Monte Carlo N-particle radiation transport computer code simulation behind the step-wedged compensator. Also, there was a good agreement between the EBT-film and the treatment-planning results on the anthropomorphic phantom. The EBT films can be accurately used as a 2D dosimeter for dose

  6. Evaluation of a Nonrigid Motion Compensation Technique Based on Spatiotemporal Features for Small Lesion Detection in Breast MRI

    Directory of Open Access Journals (Sweden)

    F. Steinbruecker

    2012-01-01

    the performance of a new nonrigid motion correction algorithm based on the optical flow method. For each of the small lesions, we extracted morphological and dynamical features describing both global and local shape, and kinetics behavior. In this paper, we compare the performance of each extracted feature set under consideration of several 2D or 3D motion compensation parameters for the differential diagnosis of enhancing lesions in breast MRI. Based on several simulation results, we determined the optimal motion compensation parameters. Our results have shown that motion compensation can improve the classification results. The results suggest that the computerized analysis system based on the non-rigid motion compensation technique and spatiotemporal features has the potential to increase the diagnostic accuracy of MRI mammography for small lesions and can be used as a basis for computer-aided diagnosis of breast cancer with MR mammography.

  7. METHOD OF SOFTWARE-BASED COMPENSATION OF TECHNOLOGICAL VARIATION IN CHROMATICITY COORDINATES OF LCD PANELS

    Directory of Open Access Journals (Sweden)

    I. O. Zharinov

    2015-05-01

    Full Text Available Subject of research. The problem of software-based compensation of technological variation in chromaticity coordinates of liquid crystal panels is considered. A method of software-based compensation of technological variation in chromaticity coordinates is proposed. The method provides the color reproduction characteristics of the series-produced samples on-board indication equipment corresponding to the sample equipment, which is taken as the standard. Method. Mathematical calculation of the profile is performed for the given model of the liquid crystal panel. The coefficients that correspond to the typical values of the chromaticity coordinates for the vertices of the triangle color coverage constitute a reference mathematical model of the plate LCD panel from a specific manufacturer. At the stage of incoming inspection the sample of the liquid crystal panel, that is to be implemented within indication equipment, is mounted on the lighting test unit, where Nokia-Test control is provided by the formation of the RGB codes for display the image of a homogeneous field in the red, green, blue and white. The measurement of the (x,y-chromaticity coordinates in red, green, blue and white colors is performed using a colorimeter with the known value of absolute error. Instead of using lighting equipment, such measurements may be carried out immediately on the sample indication equipment during customizing procedure. The measured values are used to calculate individual LCD-panel profile coefficients through the use of Grassman's transformation, establishing mutual relations between the XYZ-color coordinates and RGB codes to be used for displaying the image on the liquid crystal panel. The obtained coefficients are to be set into the memory of the graphics controller together with the functional software and then used for image displaying. Main results. The efficiency of the proposed method of software-based compensation for technological variation of

  8. Research on Acceleration Compensation Strategy of Electric Vehicle Based on Fuzzy Control Theory

    Science.gov (United States)

    Zhu, Tianjun; Li, Bin; Zong, Changfu; Wei, Zhicheng

    2017-09-01

    Nowadays, the driving technology of electric vehicle is developing rapidly. There are many kinds of methods in driving performance control technology. The paper studies the acceleration performance of electric vehicle. Under the premise of energy management, an acceleration power compensation method by fuzzy control theory based on driver intention recognition is proposed, which can meet the driver’s subjective feelings better. It avoids the problem that the pedal opening and power output are single correspondence when the traditional vehicle accelerates. Through the simulation test, this method can significantly improve the performance of acceleration and output torque smoothly in non-emergency acceleration to ensure vehicle comfortable and stable.

  9. A Compensation-Based Optimization Methodology for Gain-Boosted OPAMP

    Science.gov (United States)

    2004-05-14

    Reprint_._ 4. TiLu AWo 3UNTnU S. FUNDNIG UUMEAS A Compensation-Based Optimization Methodollogy for N00014-94-1-0931 Gain-Boosted OPAMP Jie Yuan and Nabil...Unlimited 13. •SW.&•CT %Af~xum200l..uord,) A gain-boosted OPAMP design methodology is presented. The methodology provides a systematic way of gain...boosted OPAMP optimization in terms- of AC response and settling performance. The evolution of the major poles and zeros of the gain- boosted OPAMP is

  10. Performance Characteristics and Temperature Compensation Method of Fluid Property Sensor Based on Tuning-Fork Technology

    Directory of Open Access Journals (Sweden)

    Yuan Chen

    2016-01-01

    Full Text Available Fluid property sensor (FPS based on tuning-fork technology is applied to the measurement of the contaminant level of lubricant oil. The measuring principle of FPS sensor is derived and proved together with its resolution. The performance characteristics of the FPS sensor, such as sensitivity coefficient, resolution, and quality factor, are analyzed. A temperature compensation method is proposed to eliminate the temperature-dependence of the measuring parameters, and its validity is investigated by numerical simulation of sensitivity, oscillating frequency, and dielectric constant. The values of purification efficiency obtained using microwave and without microwave are compared experimentally.

  11. MR-Based Cardiac and Respiratory Motion-Compensation Techniques for PET-MR Imaging.

    Science.gov (United States)

    Munoz, Camila; Kolbitsch, Christoph; Reader, Andrew J; Marsden, Paul; Schaeffter, Tobias; Prieto, Claudia

    2016-04-01

    Cardiac and respiratory motion cause image quality degradation in PET imaging, affecting diagnostic accuracy of the images. Whole-body simultaneous PET-MR scanners allow for using motion information estimated from MR images to correct PET data and produce motion-compensated PET images. This article reviews methods that have been proposed to estimate motion from MR images and different techniques to include this information in PET reconstruction, in order to overcome the problem of cardiac and respiratory motion in PET-MR imaging. MR-based motion correction techniques significantly increase lesion detectability and contrast, and also improve accuracy of uptake values in PET images.

  12. Research on a Fast-Closing Switch Based Fault Current Limiter with Series Compensation

    Institute of Scientific and Technical Information of China (English)

    CHEN Jin-xiang; ZOU Ji-yan; DONG En-yuan; SHI Jing

    2002-01-01

    A new type of fault current limiter (FCL) with series compensation based fast-closing switch is proposed. It is composed of a capacitor bank and a reactor in series.The main control component is a fast-closing switch connected in parallel with the capacitors, which is driven by the electromagnetic repulsion force. When fault occurs, the switch closes and bypasses the capacitors,and the fault is limited by the reactor then. Simulated analysis and experiments show that it is feasible to develop the FCL with low cost and high reliability. The effectiveness of transient stability for power system is evaluated by digital simulation.

  13. On Synergistic Integration of Adaptive Dithering Based Internal Model Control for Hysteresis Compensation in Piezoactuated Nanopositioner

    Directory of Open Access Journals (Sweden)

    Saikat Kumar Shome

    2015-01-01

    Full Text Available Piezoelectric-stack actuated platforms are very popular in the parlance of nanopositioning with myriad applications like micro/nanofactory, atomic force microscopy, scanning probe microscopy, wafer design, biological cell manipulation, and so forth. Motivated by the necessity to improve trajectory tracking in such applications, this paper addresses the problem of rate dependent hysteretic nonlinearity in piezoelectric actuators (PEA. The classical second order Dahl model for hysteresis encapsulation is introduced first, followed by the identification of parameters through particle swarm optimization. A novel inversion based feedforward mechanism in combination with a feedback compensator is proposed to achieve high-precision tracking wherein the paradoxical concept of noise as a performance enhancer is introduced in the realm of PZAs. Having observed that dither induced stochastic resonance in the presence of periodic forcing reduces tracking error, dither capability is further explored in conjunction with a novel output harmonics based adaptive control scheme. The proposed adaptive controller is then augmented with an internal model control based approach to impart robustness against parametric variations and external disturbances. The proposed control law has been employed to track multifrequency signals with consistent compensation of rate dependent hysteresis of the PEA. The results indicate a greatly improved positioning accuracy along with considerable robustness achieved with the proposed integrated approach even for dual axis tracking applications.

  14. The design and simulation of TCR(thyristor control reactor) reactive power compensation system based on Arene

    Institute of Scientific and Technical Information of China (English)

    WANG Shu-fang; ZHANG Li; JIANG Jian-guo; WANG Ru-lin

    2004-01-01

    Inevitably, the question of reactive power compensation was aroused by applied of power electronics. Based on the study of the instantaneous reactive power theory, the designs of TCR(thyristor control reactor) thyristor control reactor reactive power compensation system and TCR single closed loop strategy was proposed. In addition, as digital simulation software, Arene was applied to simulate the Jining coal mine No.2 system. The simulation results validate that the design is effective to improve power factor and stabilization of the system.

  15. Application of task-based measures of image quality to optimization and evaluation of three-dimensional reconstruction-based compensation methods in myocardial perfusion SPECT.

    Science.gov (United States)

    Frey, Eric C; Gilland, Karen L; Tsui, Benjamin M W

    2002-09-01

    In this paper, we apply the channelized Hotelling observer (CHO) using a defect detection task to the optimization and evaluation of three-dimensional iterative reconstruction-based compensation methods for myocardial perfusion single-photon emission computed tomography (SPECT). We used a population of 24 mathematical cardiac-torso phantoms that realistically model the activity and attenuation distribution in three classes of patients: females, and males with flat diaphragms and raised diaphragms. Projection data were generated and subsequently reconstructed using methods based on the ordered subsets-expectation maximization (OSEM) algorithm. The methods evaluated included compensation for attenuation, detector response blurring, and scatter in various combinations. We applied the CHO to optimize the number of iterations for OSEM and the cutoff frequency and order of a three-dimensional postreconstruction Butterworth filter. Using the optimal parameters, we then compared the compensation methods. The index of comparison in these studies was the area under the receiver operating characteristics curve (AUC) for the CHO. We found that attenuation compensation with either detector response or scatter compensation gave statistically significant increases in the AUC compared to attenuation compensation alone. The greatest increase in the AUC occurred when all three compensations were applied. These results indicate that compensation for detector response and scatter, in addition to attenuation compensation, will improve defect detectability in myocardial SPECT images.

  16. An improved gravity compensation method for high-precision free-INS based on MEC-BP-AdaBoost

    Science.gov (United States)

    Zhou, Xiao; Yang, Gongliu; Wang, Jing; Li, Jing

    2016-12-01

    In recent years, with the rapid improvement of inertial sensors (accelerometers and gyroscopes), gravity compensation has become more important for improving navigation accuracy in inertial navigation systems (INS), especially for high-precision INS. This paper proposes a mind evolutionary computation (MEC) back propagation (BP) AdaBoost algorithm neural-network-based gravity compensation method that estimates the gravity disturbance on the track based on measured gravity data. A MEC-BP-AdaBoost network-based gravity compensation algorithm used in the training process to establish the prediction model takes the carrier position (longitude and latitude) provided by INS as the input data and the gravity disturbance as the output data, and then compensates the obtained gravity disturbance into the INS’s error equations to restrain the position error propagation. The MEC-BP-AdaBoost algorithm can not only effectively avoid BP neural networks being trapped in local extrema, but also perfectly solve the nonlinearity between the input and output data that cannot be solved by traditional interpolation methods, such as least-square collocation (LSC) interpolation. The accuracy and feasibility of the proposed interpolation method are verified through numerical tests. A comparison of several other compensation methods applied in field experiments, including LSC interpolation and traditional BP interpolation, highlights the superior performance of the proposed method. The field experiment results show that the maximum value of the position error can reduce by 28% with the proposed gravity compensation method.

  17. A MEMS-Based Flow Rate and Flow Direction Sensing Platform with Integrated Temperature Compensation Scheme

    Directory of Open Access Journals (Sweden)

    Chia-Yen Lee

    2009-07-01

    Full Text Available This study develops a MEMS-based low-cost sensing platform for sensing gas flow rate and flow direction comprising four silicon nitride cantilever beams arranged in a cross-form configuration, a circular hot-wire flow meter suspended on a silicon nitride membrane, and an integrated resistive temperature detector (RTD. In the proposed device, the flow rate is inversely derived from the change in the resistance signal of the flow meter when exposed to the sensed air stream. To compensate for the effects of the ambient temperature on the accuracy of the flow rate measurements, the output signal from the flow meter is compensated using the resistance signal generated by the RTD. As air travels over the surface of the cross-form cantilever structure, the upstream cantilevers are deflected in the downward direction, while the downstream cantilevers are deflected in the upward direction. The deflection of the cantilever beams causes a corresponding change in the resistive signals of the piezoresistors patterned on their upper surfaces. The amount by which each beam deflects depends on both the flow rate and the orientation of the beam relative to the direction of the gas flow. Thus, following an appropriate compensation by the temperature-corrected flow rate, the gas flow direction can be determined through a suitable manipulation of the output signals of the four piezoresistors. The experimental results have confirmed that the resulting variation in the output signals of the integrated sensors can be used to determine not only the ambient temperature and the velocity of the air flow, but also its direction relative to the sensor with an accuracy of ± 7.5o error.

  18. A MEMS-Based Flow Rate and Flow Direction Sensing Platform with Integrated Temperature Compensation Scheme.

    Science.gov (United States)

    Ma, Rong-Hua; Wang, Dung-An; Hsueh, Tzu-Han; Lee, Chia-Yen

    2009-01-01

    This study develops a MEMS-based low-cost sensing platform for sensing gas flow rate and flow direction comprising four silicon nitride cantilever beams arranged in a cross-form configuration, a circular hot-wire flow meter suspended on a silicon nitride membrane, and an integrated resistive temperature detector (RTD). In the proposed device, the flow rate is inversely derived from the change in the resistance signal of the flow meter when exposed to the sensed air stream. To compensate for the effects of the ambient temperature on the accuracy of the flow rate measurements, the output signal from the flow meter is compensated using the resistance signal generated by the RTD. As air travels over the surface of the cross-form cantilever structure, the upstream cantilevers are deflected in the downward direction, while the downstream cantilevers are deflected in the upward direction. The deflection of the cantilever beams causes a corresponding change in the resistive signals of the piezoresistors patterned on their upper surfaces. The amount by which each beam deflects depends on both the flow rate and the orientation of the beam relative to the direction of the gas flow. Thus, following an appropriate compensation by the temperature-corrected flow rate, the gas flow direction can be determined through a suitable manipulation of the output signals of the four piezoresistors. The experimental results have confirmed that the resulting variation in the output signals of the integrated sensors can be used to determine not only the ambient temperature and the velocity of the air flow, but also its direction relative to the sensor with an accuracy of ± 7.5° error.

  19. Asynchronous update based networked predictive control system using a novel proactive compensation strategy.

    Science.gov (United States)

    Duan, Yingyao; Zuo, Xin; Liu, Jianwei

    2016-01-01

    Networked predictive control system (NPCS) has been proposed to address random delays and data dropouts in networked control systems (NCSs). A remaining challenge of this approach is that the controller has uncertain information about the actual control inputs, which leads to the predicted control input errors. The main contribution of this paper is to develop an explicit mechanism running in the distributed network nodes asynchronously, which enables the controller node to keep informed of the states of the actuator node without a priori knowledge about the network. Based on this mechanism, a novel proactive compensation strategy is proposed to develop asynchronous update based networked predictive control system (AUBNPCS). The stability criterion of AUBNPCS is derived analytically. A simulation experiment based on Truetime demonstrates the effectiveness of the scheme.

  20. Registration-based Compensation using Sparse Representation in Conformal-array STAP

    CERN Document Server

    Sun, Ke; Wang, Xiqin

    2010-01-01

    Space-time adaptive processing (STAP) is a well-suited technique to detect slow-moving targets in the presence of a clutter-spreading environment. When considering the STAP system deployed with conformal radar array (CFA), the training data is range-dependent, which results in poor detection performance of statistical-based algorithms. In this paper, we propose registration-based compensation using sparse representation (SR-RBC) to generate stationary training data. This method first converts the estimation of both the unknown configuration parameters and clutter power distribution into an ill-posed problem with the constraint of sparsity, and then utilizes the technique of sparse representation like iterative reweighted least squares (IRLS) to solve it. Based on this, the transform matrix is designed so that the processed training data behaves nearly stationary with the test cell. Since the configuration parameters as well as the clutter spectral response is obtained with full-snapshot using sparse represent...

  1. More than just the mean: moving to a dynamic view of performance-based compensation.

    Science.gov (United States)

    Barnes, Christopher M; Reb, Jochen; Ang, Dionysius

    2012-05-01

    Compensation decisions have important consequences for employees and organizations and affect factors such as retention, motivation, and recruitment. Past research has primarily focused on mean performance as a predictor of compensation, promoting the implicit assumption that alternative aspects of dynamic performance are not relevant. To address this gap in the literature, we examined the influence of dynamic performance characteristics on compensation decisions in the National Basketball Association (NBA). We predicted that, in addition to performance mean, performance trend and variability would also affect compensation decisions. Results revealed that performance mean and trend, but not variability, were significantly and positively related to changes in compensation levels of NBA players. Moreover, trend (but not mean or variability) predicted compensation when controlling for future performance, suggesting that organizations overweighted trend in their compensation decisions. Theoretical and practical implications are discussed.

  2. Brain-shift compensation using intraoperative ultrasound and constraint-based biomechanical simulation.

    Science.gov (United States)

    Morin, Fanny; Courtecuisse, Hadrien; Reinertsen, Ingerid; Le Lann, Florian; Palombi, Olivier; Payan, Yohan; Chabanas, Matthieu

    2017-08-01

    During brain tumor surgery, planning and guidance are based on preoperative images which do not account for brain-shift. However, this deformation is a major source of error in image-guided neurosurgery and affects the accuracy of the procedure. In this paper, we present a constraint-based biomechanical simulation method to compensate for craniotomy-induced brain-shift that integrates the deformations of the blood vessels and cortical surface, using a single intraoperative ultrasound acquisition. Prior to surgery, a patient-specific biomechanical model is built from preoperative images, accounting for the vascular tree in the tumor region and brain soft tissues. Intraoperatively, a navigated ultrasound acquisition is performed directly in contact with the organ. Doppler and B-mode images are recorded simultaneously, enabling the extraction of the blood vessels and probe footprint, respectively. A constraint-based simulation is then executed to register the pre- and intraoperative vascular trees as well as the cortical surface with the probe footprint. Finally, preoperative images are updated to provide the surgeon with images corresponding to the current brain shape for navigation. The robustness of our method is first assessed using sparse and noisy synthetic data. In addition, quantitative results for five clinical cases are provided, first using landmarks set on blood vessels, then based on anatomical structures delineated in medical images. The average distances between paired vessels landmarks ranged from 3.51 to 7.32 (in mm) before compensation. With our method, on average 67% of the brain-shift is corrected (range [1.26; 2.33]) against 57% using one of the closest existing works (range [1.71; 2.84]). Finally, our method is proven to be fully compatible with a surgical workflow in terms of execution times and user interactions. In this paper, a new constraint-based biomechanical simulation method is proposed to compensate for craniotomy-induced brain

  3. Online Adaptive Error Compensation SVM-Based Sliding Mode Control of an Unmanned Aerial Vehicle

    Directory of Open Access Journals (Sweden)

    Kaijia Xue

    2016-01-01

    Full Text Available Unmanned Aerial Vehicle (UAV is a nonlinear dynamic system with uncertainties and noises. Therefore, an appropriate control system has an obligation to ensure the stabilization and navigation of UAV. This paper mainly discusses the control problem of quad-rotor UAV system, which is influenced by unknown parameters and noises. Besides, a sliding mode control based on online adaptive error compensation support vector machine (SVM is proposed for stabilizing quad-rotor UAV system. Sliding mode controller is established through analyzing quad-rotor dynamics model in which the unknown parameters are computed by offline SVM. During this process, the online adaptive error compensation SVM method is applied in this paper. As modeling errors and noises both exist in the process of flight, the offline SVM one-time mode cannot predict the uncertainties and noises accurately. The control law is adjusted in real-time by introducing new training sample data to online adaptive SVM in the control process, so that the stability and robustness of flight are ensured. It can be demonstrated through the simulation experiments that the UAV that joined online adaptive SVM can track the changing path faster according to its dynamic model. Consequently, the proposed method that is proved has the better control effect in the UAV system.

  4. Compensator-based 6-DOF control for probe asteroid-orbital-frame hovering with actuator limitations

    Science.gov (United States)

    Liu, Xiaosong; Zhang, Peng; Liu, Keping; Li, Yuanchun

    2016-05-01

    This paper is concerned with 6-DOF control of a probe hovering in the orbital frame of an asteroid. Considering the requirements of the scientific instruments pointing direction and orbital position in practical missions, the coordinate control of relative attitude and orbit between the probe and target asteroid is imperative. A 6-DOF dynamic equation describing the relative translational and rotational motion of a probe in the asteroid's orbital frame is derived, taking the irregular gravitation, model and parameter uncertainties and external disturbances into account. An adaptive sliding mode controller is employed to guarantee the convergence of the state error, where the adaptation law is used to estimate the unknown upper bound of system uncertainty. Then the controller is improved to deal with the practical problem of actuator limitations by introducing a RBF neural network compensator, which is used to approximate the difference between the actual control with magnitude constraint and the designed nominal control law. The closed-loop system is proved to be asymptotically stable through the Lyapunov stability analysis. Numerical simulations are performed to compare the performances of the preceding designed control laws. Simulation results demonstrate the validity of the control scheme using the compensator-based adaptive sliding mode control law in the presence of actuator limitations, system uncertainty and external disturbance.

  5. ADAPTIVE CONTROL OF TWO-LINK ROBOT MANIPULATOR BASED ON THE METHOD OF CONSECUTIVE COMPENSATOR

    Directory of Open Access Journals (Sweden)

    A. A. Margun

    2014-03-01

    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.

  6. Load monitoring and compensation strategies for guided-waves based structural health monitoring using piezoelectric transducers

    Science.gov (United States)

    Roy, Surajit; Ladpli, Purim; Chang, Fu-Kuo

    2015-09-01

    Accurate interpretation of in-situ piezoelectric sensor signals is a challenging task. This paper presents the development of a numerical compensation model based on physical insight to address the influence of structural loads on piezo-sensor signals. The model requires knowledge of in-situ strain and temperature distribution in a structure while acquiring piezoelectric sensor signals. The parameters of the numerical model are obtained using experiments on flat aluminum plate under uniaxial tensile loading. It is shown that the model parameters obtained experimentally can be used for different structures, and sensor layout. Furthermore, the combined effects of load and temperature on the piezo-sensor response are also investigated and it is observed that both of these factors have a coupled effect on the sensor signals. It is proposed to obtain compensation model parameters under a range of operating temperatures to address this coupling effect. An important outcome of this study is a new load monitoring concept using in-situ piezoelectric sensor signals to track changes in the load paths in a structure.

  7. Perceptual learning improves adult amblyopic vision through rule-based cognitive compensation.

    Science.gov (United States)

    Zhang, Jun-Yun; Cong, Lin-Juan; Klein, Stanley A; Levi, Dennis M; Yu, Cong

    2014-04-01

    We investigated whether perceptual learning in adults with amblyopia could be enabled to transfer completely to an orthogonal orientation, which would suggest that amblyopic perceptual learning results mainly from high-level cognitive compensation, rather than plasticity in the amblyopic early visual brain. Nineteen adults (mean age = 22.5 years) with anisometropic and/or strabismic amblyopia were trained following a training-plus-exposure (TPE) protocol. The amblyopic eyes practiced contrast, orientation, or Vernier discrimination at one orientation for six to eight sessions. Then the amblyopic or nonamblyopic eyes were exposed to an orthogonal orientation via practicing an irrelevant task. Training was first performed at a lower spatial frequency (SF), then at a higher SF near the cutoff frequency of the amblyopic eye. Perceptual learning was initially orientation specific. However, after exposure to the orthogonal orientation, learning transferred to an orthogonal orientation completely. Reversing the exposure and training order failed to produce transfer. Initial lower SF training led to broad improvement of contrast sensitivity, and later higher SF training led to more specific improvement at high SFs. Training improved visual acuity by 1.5 to 1.6 lines (P learning suggests that perceptual learning in amblyopia may reflect high-level learning of rules for performing a visual discrimination task. These rules are applicable to new orientations to enable learning transfer. Therefore, perceptual learning may improve amblyopic vision mainly through rule-based cognitive compensation.

  8. Image-based iterative compensation of motion artifacts in computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Schretter, Colas; Rose, Georg; Bertram, Matthias [Philips Research Europe, Weisshausstrasse 2, 52066 Aachen, Germany and Otto-von-Guericke University, Universitaetsplatz 2, 39016 Magdeburg (Germany); Otto-von-Guericke University, Universitaetsplatz 2, 39016 Magdeburg (Germany); Philips Research Europe, Weisshausstrasse 2, 52066 Aachen (Germany)

    2009-11-15

    Purpose: This article presents an iterative method for compensation of motion artifacts for slowly rotating computed tomography (CT) systems. Patient's motion introduces inconsistencies among projections and yields severe reconstruction artifacts for free-breathing acquisitions. Streaks and doubling of structures can appear and the resolution is limited by strong blurring. Methods: The rationale of the proposed motion compensation method is to iteratively correct the reconstructed image by first decomposing the perceived motion in projection space, then reconstructing the motion artifacts in image space, and finally subtracting the artifacts from an initial image. The initial image is reconstructed from the acquired data and might contain motion blur artifacts but, nevertheless, is considered as a reference for estimating the reconstruction artifacts. Results: Qualitative and quantitative figures are shown for experiments based on numerically simulated projections of a sequence of clinical images resulting from a respiratory-gated helical CT acquisition. The border of the diaphragm becomes progressively sharper and the contrast improves for small structures in the lungs. Conclusions: The originality of the technique stems from the fact that the patient motion is not explicitly estimated but the motion artifacts are reconstructed in image space. This approach could provide sharp static anatomical images on interventional C-arm systems or on slowly rotating X-ray equipments in radiotherapy.

  9. Compressed sensing techniques for receiver based post-compensation of transmitter's nonlinear distortions in OFDM systems

    KAUST Repository

    Owodunni, Damilola S.

    2014-04-01

    In this paper, compressed sensing techniques are proposed to linearize commercial power amplifiers driven by orthogonal frequency division multiplexing signals. The nonlinear distortion is considered as a sparse phenomenon in the time-domain, and three compressed sensing based algorithms are presented to estimate and compensate for these distortions at the receiver using a few and, at times, even no frequency-domain free carriers (i.e. pilot carriers). The first technique is a conventional compressed sensing approach, while the second incorporates a priori information about the distortions to enhance the estimation. Finally, the third technique involves an iterative data-aided algorithm that does not require any pilot carriers and hence allows the system to work at maximum bandwidth efficiency. The performances of all the proposed techniques are evaluated on a commercial power amplifier and compared. The error vector magnitude and symbol error rate results show the ability of compressed sensing to compensate for the amplifier\\'s nonlinear distortions. © 2013 Elsevier B.V.

  10. Load monitoring and compensation strategies for guided-waves based structural health monitoring using piezoelectric transducers

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Surajit; Ladpli, Purim; Chang, Fu-Kuo

    2015-09-01

    Accurate interpretation of in-situ piezoelectric sensor signals is a challenging task. This article presents the development of a numerical compensation model based on physical insight to address the influence of structural loads on piezo-sensor signals. The model requires knowledge of in-situ strain and temperature distribution in a structure while acquiring sensor signals. The parameters of the numerical model are obtained using experiments on flat aluminum plate under uniaxial tensile loading. It is shown that the model parameters obtained experimentally can be used for different structures, and sensor layout. Furthermore, the combined effects of load and temperature on the piezo-sensor response are also investigated and it is observed that both of these factors have a coupled effect on the sensor signals. It is proposed to obtain compensation model parameters under a range of operating temperatures to address this coupling effect. An important outcome of this study is a new load monitoring concept using in-situ piezoelectric sensor signals to track changes in the load paths in a structure.

  11. Supplementary Controller Design for SSR Damping in a Series-Compensated DFIG-Based Wind Farm

    Directory of Open Access Journals (Sweden)

    Minqiang Hu

    2012-11-01

    Full Text Available The increasing presence of wind power in power systems will likely drive the integration of large wind farms with electrical networks that are series-compensated to sustain large power flows. This may potentially lead to subsynchronous resonance (SSR issues. In this paper, a supplementary controller on the grid-side converter (GSC control loop is designed to mitigate SSR for wind power systems based on doubly fed induction generators (DFIGs with back-to-back converters. Different supplementary controller feedback signals and modulated-voltage injecting points are proposed and compared based on modal analysis and verified through root locus analysis to identify the optimal feedback signal and the most effective control location for SSR damping. The validity and effectiveness of the proposed supplemental control are demonstrated on the IEEE first benchmark model for computer simulations of SSR by means of time domain simulation analysis using Matlab/Simulink.

  12. Shunt PWM advanced var compensators based on voltage source inverters for Facts applications

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Pedro G.; Misaka, Isamu; Watanabe, Edson H. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia

    1994-12-31

    Increased attention has been given to improving power system operation. This paper presents modeling, analysis and design of reactive shunt power compensators based on PWM-Voltage Source Inverters (Pulse Width Modulation -Voltage Source Inverters). (Pulse Width Modulation - Voltage Source Inverters). The control algorithm is based on new concepts of instantaneous active and reactive power theory. The objective is to show that with a small capacitor in the side of a 3-phase PWM-VSI it is possible to synthesize a variable reactive (capacitive or inductive) device. Design procedures and experimental results are presented. The feasibility of this method was verified by digital simulations and measurements on a small scale model. (author) 9 refs., 12 figs.

  13. 3D model-based catheter tracking for motion compensation in EP procedures

    Science.gov (United States)

    Brost, Alexander; Liao, Rui; Hornegger, Joachim; Strobel, Norbert

    2010-02-01

    Atrial fibrillation is the most common sustained heart arrhythmia and a leading cause of stroke. Its treatment by radio-frequency catheter ablation, performed using fluoroscopic image guidance, is gaining increasingly more importance. Two-dimensional fluoroscopic navigation can take advantage of overlay images derived from pre-operative 3-D data to add anatomical details otherwise not visible under X-ray. Unfortunately, respiratory motion may impair the utility of these static overlay images for catheter navigation. We developed an approach for image-based 3-D motion compensation as a solution to this problem. A bi-plane C-arm system is used to take X-ray images of a special circumferential mapping catheter from two directions. In the first step of the method, a 3-D model of the device is reconstructed. Three-dimensional respiratory motion at the site of ablation is then estimated by tracking the reconstructed catheter model in 3-D. This step involves bi-plane fluoroscopy and 2-D/3-D registration. Phantom data and clinical data were used to assess our model-based catheter tracking method. Experiments involving a moving heart phantom yielded an average 2-D tracking error of 1.4 mm and an average 3-D tracking error of 1.1 mm. Our evaluation of clinical data sets comprised 469 bi-plane fluoroscopy frames (938 monoplane fluoroscopy frames). We observed an average 2-D tracking error of 1.0 mm +/- 0.4 mm and an average 3-D tracking error of 0.8 mm +/- 0.5 mm. These results demonstrate that model-based motion-compensation based on 2-D/3-D registration is both feasible and accurate.

  14. A convenient look-up-table based method for the compensation of non-linear error in digital fringe projection

    Directory of Open Access Journals (Sweden)

    Chen Xiong

    2016-01-01

    Full Text Available Although the structured light system that uses digital fringe projection has been widely implemented in three-dimensional surface profile measurement, the measurement system is susceptible to non-linear error. In this work, we propose a convenient look-up-table-based (LUT-based method to compensate for the non-linear error in captured fringe patterns. Without extra calibration, this LUT-based method completely utilizes the captured fringe pattern by recording the full-field differences. Then, a phase compensation map is established to revise the measured phase. Experimental results demonstrate that this method works effectively.

  15. Observer-based predictive controller design with network-enhanced time-delay compensation

    Science.gov (United States)

    Florin Caruntu, Constantin

    2015-02-01

    State feedback control is very attractive due to the precise computation of the gain matrix, but the implementation of a state feedback controller is possible only when all state variables are directly measurable. This condition is almost impossible to accomplish due to the excess number of required sensors or unavailability of states for measurement in most of the practical situations. Hence, the need for an estimator or observer is obvious to estimate all the state variables by observing the input and the output of the controlled system. As such, the goal of this paper is to provide a control design methodology based on a Luenberger observer design that can assure the closed-loop performances of a vehicle drivetrain with backlash, while compensating the network-enhanced time-varying delays. This goal is achieved in a sequential manner: firstly, a piecewise linear model of two inertias drivetrain, which takes into consideration the backlash nonlinearity and the network-enhanced time-varying delay effects is derived; then, a Luenberger observer which estimates the state variables is synthesized and the robust full state-feedback predictive controller based on flexible control Lyapunov functions is designed to explicitly take into account the bounds of the disturbances caused by time-varying delays and to guarantee also the input-to-state stability of the system in a non-conservative way. The full state-feedback predictive control strategy based on the Luenberger observer design was experimentally tested on a vehicle drivetrain emulator controlled through controller area network, with the aim of minimizing the backlash effects while compensating the network-enhanced delays.

  16. Disturbance Observer-Based Simple Nonlinearity Compensation for Matrix Converter Drives

    Directory of Open Access Journals (Sweden)

    Kyo-Beum Lee

    2009-01-01

    Full Text Available This paper presents a new method to compensate the nonlinearity for matrix converter drives using disturbance observer. The nonlinearity of matrix converter drives such as commutation delay, turn-on and turn-off time of switching device, and on-state switching device voltage drop is modeled by disturbance observer and compensated. The proposed method does not need any additional hardware and offline experimental measurements. The proposed compensation method is applied for high-performance induction motor drives using a 3 kW matrix converter system without a speed sensor. Simulation and experimental results show that the proposed method using disturbance observer provides good compensating characteristics.

  17. Disturbance Observer-Based Simple Nonlinearity Compensation for Matrix Converter Drives

    DEFF Research Database (Denmark)

    Lee, Kyo-Beum; Blaabjerg, Frede

    2009-01-01

    This paper presents a new method to compensate the nonlinearity for matrix converter drives using disturbance observer. The nonlinearity of matrix converter drives such as commutation delay, turn-on and turn-off time of switching device, and on-state switching device voltage drop is modeled...... by disturbance observer and compensated. The proposed method does not need any additional hardware and offline experimental measurements. The proposed compensation method is applied for highperformance induction motor drives using a 3kW matrix converter system without a speed sensor. Simulation and experimental...... results show that the proposed method using disturbance observer provides good compensating characteristics....

  18. Online adaptive parameter identification of PMSM based on the dead-time compensation

    Science.gov (United States)

    Chen, Yong; Zhou, Fu; Liu, Xia; Hu, Eric

    2015-07-01

    This paper presents a method of online identification of the parameters of permanent magnet synchronous motors (PMSM) by model reference adaptive identification based on Popov Super Stability Theory. Firstly, the relations of parameters in the Field Orientation Control (FOC) system are analysed. Secondly, the proposed identification method of PMSM concerns two parts. In the case of high-speed operation of the motor, the method can accurately identify the inductance in dq-axis and the permanent magnet (PM) flux linkage. On the other hand, in the case of low speed, it can accurately identify the winding resistance of the stator. The method does not require additional excitation signals, but only makes use of motor voltage, current and their deviations. Thirdly, a simple and effective dead-time compensation method has been applied to inhibit the dead-time effects on the parameter identification. At last, the simulation and experiment results clearly demonstrate the validity and feasibility of the method.

  19. Steel Temperature Compensating Model With Multi-Factor Coupling Based on Ladle Thermal State

    Institute of Scientific and Technical Information of China (English)

    WU Peng-fei; XU An-jun; TIAN Nai-yuan; HE Dong-feng

    2012-01-01

    Combined with the parameters of the production process of a steel factory, numerical simulations for a new ladle from preheating to turnover are conducted using the finite element analysis system software (ANSYS). The measured data proved that the simulated results are reliable. The effects of preheating time, thermal cycling times, and empty package time on steel temperature are calculated, an ideal preheating time is provided, besides, based on the analysis of a single factor and use the nonlinear analysis method, a steel temperature compensating model with di- versified coupling factors is proposed, with the largest error of the present coupling model at 1. 462 ~C, and the er- rors between actual and target steel temperature in tundish after the model is applied to practical production are basi- cally controlled within -4-6 ~C, which can meet the accuracy of the manufacturer and has a practical guiding significance for the production in steelmaking workshops.

  20. Realization of LOS (Line of Sight) stabilization based on reflector using carrier attitude compensation method

    Science.gov (United States)

    Mao, Yao; Tian, Jing; Ma, Jia-guang

    2015-02-01

    The techonology of LOS stabilization is widely applicated in moving carrier photoelectric systems such as shipborne, airborne and so on. In application situations with compact structure, such as LOS stabilization system of unmanned aerial vehicle, LOS stabilization based on reflector is adopted, and the detector is installed on the carrier to reduce the volume of stabilized platform and loading weight. However, the LOS deflection angle through reflector and the rotation angle of the reflector has a ratio relation of 2:1, simple reflector of stable inertial space can not make the optical axis stable. To eliminate the limitation of mirror stabilizing method, this article puts forward the carrier attitude compensation method, which uses the inertial sensor installed on the carrier to measure the attitude change of the carrier, and the stabilized platform rotating half of the carrier turbulence angle to realize the LOS stabilization.

  1. Adaptive update using visual models for lifting-based motion-compensated temporal filtering

    Science.gov (United States)

    Li, Song; Xiong, H. K.; Wu, Feng; Chen, Hong

    2005-03-01

    Motion compensated temporal filtering is a useful framework for fully scalable video compression schemes. However, when supposed motion models cannot represent a real motion perfectly, both the temporal high and the temporal low frequency sub-bands may contain artificial edges, which possibly lead to a decreased coding efficiency, and ghost artifacts appear in the reconstructed video sequence at lower bit rates or in case of temporal scaling. We propose a new technique that is based on utilizing visual models to mitigate ghosting artifacts in the temporal low frequency sub-bands. Specifically, we propose content adaptive update schemes where visual models are used to determine image dependent upper bounds on information to be updated. Experimental results show that the proposed algorithm can significantly improve subjective visual quality of the low-pass temporal frames and at the same time, coding performance can catch or exceed the classical update steps.

  2. Maximum Likelihood A Priori Knowledge Interpolation-Based Handset Mismatch Compensation for Robust Speaker Identification

    Institute of Scientific and Technical Information of China (English)

    LIAO Yuanfu; ZHUANG Zhixian; YANG Jyhher

    2008-01-01

    Unseen handset mismatch is the major source of performance degradation in speaker identifica-tion in telecommunication environments.To alleviate the problem,a maximum likelihood a priori knowledge interpolation (ML-AKI)-based handset mismatch compensation approach is proposed.It first collects a set of handset characteristics of seen handsets to use as the a priori knowledge for representing the space of handsets.During evaluation the characteristics of an unknown test handset are optimally estimated by in-terpolation from the set of the a pdod knowledge.Experimental results on the HTIMIT database show that the ML-AKI method can improve the average speaker identification rate from 60.0% to 74.6% as compared with conventional maximum a posteriori-adapted Gaussian mixture models.The proposed ML-AKI method is a promising method for robust speaker identification.

  3. Compensation method for temperature error of fiber optical gyroscope based on relevance vector machine.

    Science.gov (United States)

    Wang, Guochen; Wang, Qiuying; Zhao, Bo; Wang, Zhenpeng

    2016-02-10

    Aiming to improve the bias stability of the fiber optical gyroscope (FOG) in an ambient temperature-change environment, a temperature-compensation method based on the relevance vector machine (RVM) under Bayesian framework is proposed and applied. Compared with other temperature models such as quadratic polynomial regression, neural network, and the support vector machine, the proposed RVM method possesses higher accuracy to explain the temperature dependence of the FOG gyro bias. Experimental results indicate that, with the proposed RVM method, the bias stability of an FOG can be apparently reduced in the whole temperature ranging from -40°C to 60°C. Therefore, the proposed method can effectively improve the adaptability of the FOG in a changing temperature environment.

  4. Voltage stability index based optimal placement of static VAR compensator and sizing using Cuckoo search algorithm

    Science.gov (United States)

    Venkateswara Rao, B.; Kumar, G. V. Nagesh; Chowdary, D. Deepak; Bharathi, M. Aruna; Patra, Stutee

    2017-07-01

    This paper furnish the new Metaheuristic algorithm called Cuckoo Search Algorithm (CSA) for solving optimal power flow (OPF) problem with minimization of real power generation cost. The CSA is found to be the most efficient algorithm for solving single objective optimal power flow problems. The CSA performance is tested on IEEE 57 bus test system with real power generation cost minimization as objective function. Static VAR Compensator (SVC) is one of the best shunt connected device in the Flexible Alternating Current Transmission System (FACTS) family. It has capable of controlling the voltage magnitudes of buses by injecting the reactive power to system. In this paper SVC is integrated in CSA based Optimal Power Flow to optimize the real power generation cost. SVC is used to improve the voltage profile of the system. CSA gives better results as compared to genetic algorithm (GA) in both without and with SVC conditions.

  5. Deserved Compensation

    Institute of Scientific and Technical Information of China (English)

    LI LI

    2010-01-01

    @@ China's National People's Congress (NPC), the top legislature, recently adopted amendments to the Law on State Compensation, granting citizens greater power to obtain compensation when their rights are violated by the state.

  6. Executive Compensation: A Brief Review

    OpenAIRE

    Bognanno, Michael L.

    2010-01-01

    Chief executive officer (CEO) compensation is defined as the sum of base pay, bonuses, stock grants, stock options, other forms of compensation and benefits. Inflation?adjusted, median total CEO compensation in the United States almost tripled between 1992 and 2000, with grants of stock options evolving to be the largest component of compensation. This article presents the arguments for and against this level and composition of CEO compensation.

  7. Executive Compensation: A Brief Review

    OpenAIRE

    Bognanno, Michael L.

    2010-01-01

    Chief executive officer (CEO) compensation is defined as the sum of base pay, bonuses, stock grants, stock options, other forms of compensation and benefits. Inflation?adjusted, median total CEO compensation in the United States almost tripled between 1992 and 2000, with grants of stock options evolving to be the largest component of compensation. This article presents the arguments for and against this level and composition of CEO compensation.

  8. Adaptive actuator failure compensation control based on MMST grouping for a class of MIMO nonlinear systems with guaranteed transient performance

    Science.gov (United States)

    Zhang, Shao-Jie; Qiu, Xiang-Wei; Jiang, Bin; Liu, Chun-Sheng

    2015-03-01

    This paper presents a new adaptive compensation control approach for a class of multi-input multi-output (MIMO) nonlinear systems with actuator failures. In order to enlarge the set of compensable actuator failures, an actuators grouping scheme based on multiple model switching and tuning (MMST) is proposed for the nonlinear MIMO minimum-phase systems with multiple actuator failures. Then, an adaptive compensation scheme based on prescribed performance bound (PPB) which characterises the convergence rate and maximum overshoot of the tracking error is designed for the systems to ensure closed-loop signal boundedness and asymptotic output tracking despite unknown actuator failures. Simulation results are given to show the effectiveness of the control design.

  9. Case Study of Marine Ecological Compensation Criteria Based on Environmental Risk

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji-wei; YANG Zhi-feng; TANG Jun-jian; CHEN Chu-han

    2009-01-01

    This paper forecasted and identified the environmental risks and ecological effect caused by chemical spill by simulating the xylene spill in Xiamen waters. The evaluation objects of ecological damage include four parts: marine ecosystem services, sea water quality, marine biological resources (plankton, benthos, nekton, etc.), and beach habitat. The ecological compensation criterion was confirmed as 1.73 million Yuan per year in the short term and 8.09 million Yuan in the long term. And an ecological compensation mode was suggested to be that if the chemical spill does not occur this year, the compensation will return to the enterprise next year; while if chemical spill occurs, the compensation will not be returned. The encouragement mechanism "returning compensation if no spill" might motivate enterprises to improve the environmental risk management and avoid the risks.

  10. Image Quality Assessment Based on Local Linear Information and Distortion-Specific Compensation.

    Science.gov (United States)

    Wang, Hanli; Fu, Jie; Lin, Weisi; Hu, Sudeng; Kuo, C-C Jay; Zuo, Lingxuan

    2016-12-14

    Image Quality Assessment (IQA) is a fundamental yet constantly developing task for computer vision and image processing. Most IQA evaluation mechanisms are based on the pertinence of subjective and objective estimation. Each image distortion type has its own property correlated with human perception. However, this intrinsic property may not be fully exploited by existing IQA methods. In this paper, we make two main contributions to the IQA field. First, a novel IQA method is developed based on a local linear model that examines the distortion between the reference and the distorted images for better alignment with human visual experience. Second, a distortion-specific compensation strategy is proposed to offset the negative effect on IQA modeling caused by different image distortion types. These score offsets are learned from several known distortion types. Furthermore, for an image with an unknown distortion type, a Convolutional Neural Network (CNN) based method is proposed to compute the score offset automatically. Finally, an integrated IQA metric is proposed by combining the aforementioned two ideas. Extensive experiments are performed to verify the proposed IQA metric, which demonstrate that the local linear model is useful in human perception modeling, especially for individual image distortion, and the overall IQA method outperforms several state-of-the-art IQA approaches.

  11. Compensation of Linear Multiscale Doppler for OFDM-Based Underwater Acoustic Communication Systems

    Directory of Open Access Journals (Sweden)

    A. E. Abdelkareem

    2012-01-01

    Full Text Available In particular cases, such as acceleration, it is required to design a receiver structure that is capable of accomplishing time varying Doppler compensation. In this paper, two approaches are taken into consideration in order to estimate the symbol timing offset parameter. The first method employed to achieve an estimate of this particular parameter is based upon centroid localization and this prediction is reinforced by a second technique which utilises linear prediction, based on the assumption that the speed changes linearly during the OFDM symbol time. Subsequently, the two estimations of the symbol timing offset parameter are smoothed in order to obtain a fine tuned approximation of the Doppler scale. Additionally, the effects of weighting coefficients on smoothing the Doppler scale and on the performance of the receiver are also investigated. The proposed receiver is investigated, incorporating an improvement that includes fine tuning of the coarse timing synchronization in order to accommodate the time-varying Doppler. Based on this fine-tuned timing synchronization, an extension to the improved receiver is presented to assess the performance of two point correlations. The proposed algorithms' performances were investigated using real data obtained from an experiment that took place in the North Sea in 2009.

  12. A Novel Filter Dependent CFR Scheme with Waterfilling Based Code Domain Compensation

    Science.gov (United States)

    Chang, Hyung Min; Lee, Won Cheol

    This paper proposes a novel crest factor reduction (CFR) algorithm applicable to currently deployed W-CDMA base stations. The peak-to-average ratio (PAR) reduction of the multiple carrier mixed signal, namely CFR, has been an issue in order to convey the benefit of using low-cost power amplifiers. The simple final clipping method (SFCM) as a conventional method has been widely utilized due to its simplicity and effectiveness. However, the SFCM degrades the adjacent channel leakage ratio (ACLR) characteristic as well as the signal quality indicated by either the error vector magnitude (EVM) or the peak code domain error (PCDE). Conventionally, in order to alleviate this undesired deterioration, extra channel filtering and signal quality enhancement followed by CFR might be processed in an open-loop style. Alternatively, to perform CFR by maintaining the PAR as low as possible subject to satisfying the prescribed ACLR and EVM/PCDE performance, this paper introduces the prediction filter dependent peak reduction (PFDPR) process collaboratively working with dynamic waterfilling-based code domain compensation (DWCDC). To verify the superiority of the proposed CFR algorithm, tentative simulations are conducted while maintaining the rules of legitimate W-CDMA base station test specifications.

  13. An approach to enhance self-compensation capability in paper-based devices for chemical sensing.

    Science.gov (United States)

    Lo, Shih-Jie; Chen, Kuan-Hung; Yao, Da-Jeng

    2015-12-01

    This paper describes a simple design for increasing the tolerance of reagent dislocation on a paper-based platform using a combination of wax-treated paper and a vortex mixer. To date, massive budgetary funds are required in the biotechnological industry to develop new applications; a large part of that cost is attributable to the screening of specific chemical compounds. Here, we propose using a liquid-handling robot to automatically deposit selected reagents on a paper-based platform. We also present a preliminary concept approach for developing a reagent placing device with simple and inexpensive features. A defect of inaccuracy was observed between droplet location and test well location after viewing the performance of the liquid-handling robot on our paper-based platform. Because of dislocation error resulting from robotic reagent placement, we decided to apply an external, rotational force following droplet placement in order to compensate for the distance of reagent dislocation. Note, the largest distance of reagent dislocation was determined by examining the results of altering applied reagent volume, but not concentration, in volumes from 5 µL to 30 µL in a series of experiments. As a result of these experiments, we observed that dislocation was positively affected by an increase in applied volume. A colorimetric assay for nitrite detection was also performed to confirm the feasibility of this method. This work, we believe, can minimize the cost of chemical compound screening for the biotechnological industry.

  14. Fiber Bragg Grating Sensor Array System Based on Digital Phase Generated Carrier Demodulation and Reference Compensation Method

    Institute of Scientific and Technical Information of China (English)

    Jun He; Fang Li; Hao Xiao; Yu-Liang Liu

    2008-01-01

    A novel fiber Bragg grating (FBG) sensor array system based on digital phase generated carrier (PGC) demodulation and reference compensation method is proposed and set up. Experimental results confirm that the digital PGC demodulation can be used for wavelength-division-multiplexed FBG sensor array and the reference compensation method can reduce the environmental interference by approximately 40 dB in the frequency range from 20 Hz to 2 kHz. The minimum detectable wavelength-shift of the sensor system is 1×10-3 pm/Hz1/2.

  15. Walking Stability Compensation Strategy of a Small Humanoid Robot Based on the Error of Swing Foot Height and Impact Force

    Directory of Open Access Journals (Sweden)

    Jiandong Zhao

    2013-05-01

    Full Text Available In order to reduce the impact force of swing legs and improve walking stability when a small humanoid robot is walking, a set of impact dynamics equations based on the second kind Lagrange equation is produced, and an impact compensation control strategy with a BP network optimized by a particle swarm algorithm is designed. The core element of the compensation controller is replacing the error back propagation with a particle swarm algorithm. Due to the regulating joints of the knee, hip and ankle, the walking process is more stable than before. The experiment results show that when the left swing leg lands, the impact force drops by 2N and 1.5N respectively in the moments 4.5s and 10.5s. Therefore, the compensation strategy can reduce the impact force effectively and improve the walking stability.

  16. Image registration of interferometric inverse synthetic aperture radar imaging system based on joint respective window sampling and modified motion compensation

    Science.gov (United States)

    Tian, Biao; Shi, Si; Liu, Yang; Xu, Shiyou; Chen, Zengping

    2015-01-01

    We propose a new image registration method based on joint respective window sampling (RWS) and modified motion compensation (MMC) in an interferometric inverse synthetic aperture radar (InISAR) imaging system using two antennas. The causation and quantitative analysis of the offset between two ISAR images of different antennas along the baseline are analyzed. In the proposed method, the RWS method, according to the measured distance between the target and different antennas, compensates the offset in the range direction. The MMC method is adopted to eliminate the offset in the Doppler direction. Simulation results demonstrate that the offset between the two ISAR images can be compensated effectively, consequently achieving a high-quality three-dimensional InISAR image.

  17. A case study of a team-based, quality-focused compensation model for primary care providers.

    Science.gov (United States)

    Greene, Jessica; Hibbard, Judith H; Overton, Valerie

    2014-06-01

    In 2011, Fairview Health Services began replacing their fee-for-service compensation model for primary care providers (PCPs), which included an annual pay-for-performance bonus, with a team-based model designed to improve quality of care, patient experience, and (eventually) cost containment. In-depth interviews and an online survey of PCPs early after implementation of the new model suggest that it quickly changed the way many PCPs practiced. Most PCPs reported a shift in orientation toward quality of care, working more collaboratively with their colleagues and focusing on their full panel of patients. The majority reported that their quality of care had improved because of the model and that their colleagues' quality had to. The comprehensive change did, however, result in lower fee-for-service billing and reductions in PCP satisfaction. While Fairview's compensation model is still a work in progress, their early experiences can provide lessons for other delivery systems seeking to reform PCP compensation.

  18. An ecological compensation standard based on emergy theory for the Xiao Honghe River Basin.

    Science.gov (United States)

    Guan, Xinjian; Chen, Moyu; Hu, Caihong

    2015-01-01

    The calculation of an ecological compensation standard is an important, but also difficult aspect of current ecological compensation research. In this paper, the factors affecting the ecological-economic system in the Xiao Honghe River Basin, China, including the flow of energy, materials, and money, were calculated using the emergy analysis method. A consideration of the relationships between the ecological-economic value of water resources and ecological compensation allowed the ecological-economic value to be calculated. On this basis, the amount of water needed for dilution was used to develop a calculation model for the ecological compensation standard of the basin. Using the Xiao Honghe River Basin as an example, the value of water resources and the ecological compensation standard were calculated using this model according to the emission levels of the main pollutant in the basin, chemical oxygen demand. The compensation standards calculated for the research areas in Xipin, Shangcai, Pingyu, and Xincai were 34.91 yuan/m3, 32.97 yuan/m3, 35.99 yuan/m3, and 34.70 yuan/m3, respectively, and such research output would help to generate and support new approaches to the long-term ecological protection of the basin and improvement of the ecological compensation system.

  19. Rationalizing vaccine injury compensation.

    Science.gov (United States)

    Mello, Michelle M

    2008-01-01

    Legislation recently adopted by the United States Congress provides producers of pandemic vaccines with near-total immunity from civil lawsuits without making individuals injured by those vaccines eligible for compensation through the Vaccine Injury Compensation Program. The unusual decision not to provide an alternative mechanism for compensation is indicative of a broader problem of inconsistency in the American approach to vaccine-injury compensation policy. Compensation policies have tended to reflect political pressures and economic considerations more than any cognizable set of principles. This article identifies a set of ethical principles bearing on the circumstances in which vaccine injuries should be compensated, both inside and outside public health emergencies. A series of possible bases for compensation rules, some grounded in utilitarianism and some nonconsequentialist, are discussed and evaluated. Principles of fairness and reasonableness are found to constitute the strongest bases. An ethically defensible compensation policy grounded in these principles would make a compensation fund available to all individuals with severe injuries and to individuals with less-severe injuries whenever the vaccination was required by law or professional duty.

  20. Configuration maintaining control of three-body ring tethered system based on thrust compensation

    Science.gov (United States)

    Huang, Panfeng; Liu, Binbin; Zhang, Fan

    2016-06-01

    Space multi-tethered systems have shown broad prospects in remote observation missions. This paper mainly focuses on the dynamics and configuration maintaining control of space spinning three-body ring tethered system for such mission. Firstly, we establish the spinning dynamic model of the three-body ring tethered system considering the elasticity of the tether using Newton-Euler method, and then validate the suitability of this model by numerical simulation. Subsequently, LP (Likins-Pringle) initial equilibrium conditions for the tethered system are derived based on rigid body's equilibrium theory. Simulation results show that tether slack, snapping and interaction between the tethers exist in the three-body ring system, and its' configuration can not be maintained without control. Finally, a control strategy based on thrust compensation, namely thrust to simulate tether compression under LP initial equilibrium conditions is designed to solve the configuration maintaining control problem. Control effects are verified by numerical simulation compared with uncontrolled situation. Simulation results show that the configuration of the three-body ring tethered system could maintain under this active control strategy.

  1. Static Synchronous Series Compensator Controller based on Fuzzy Logic Control for Power System Stabilization

    Directory of Open Access Journals (Sweden)

    Prechanon Kumkratug

    2011-01-01

    Full Text Available Problem statement: Modern power system consists of the complicated network of transmission lines and carries heavy demand. Thus they cause in the stability problem. Approach: Static Synchronous Series Compensator (SSSC is a power electronic based device that has the capability of controlling the power flow through a line. The series voltage injection model of SSSC is modeled into power flow equation and thus it is used to determine its control strategy. This study applies the fuzzy logic applies the SSSC to improve stability of power system. The mathematical model and control strategy of a SSSC are presented. The SSSC is represented by variable voltage injection with associate transformer leakage control to derive control strategy of SSSC. The swing curves of the three phase faulted power system without and with a SSSC is tested and compared in various cases. Results: The swing curve of the system with SSSC based fuzzy logic control has the less amplitude during the dynamic period. Conclusion: It was found from simulation results that SSSC can improve the power system oscillation after disturbance.

  2. Vehicle Position Estimation Based on Magnetic Markers: Enhanced Accuracy by Compensation of Time Delays

    Directory of Open Access Journals (Sweden)

    Yeun-Sub Byun

    2015-11-01

    Full Text Available The real-time recognition of absolute (or relative position and orientation on a network of roads is a core technology for fully automated or driving-assisted vehicles. This paper presents an empirical investigation of the design, implementation, and evaluation of a self-positioning system based on a magnetic marker reference sensing method for an autonomous vehicle. Specifically, the estimation accuracy of the magnetic sensing ruler (MSR in the up-to-date estimation of the actual position was successfully enhanced by compensating for time delays in signal processing when detecting the vertical magnetic field (VMF in an array of signals. In this study, the signal processing scheme was developed to minimize the effects of the distortion of measured signals when estimating the relative positional information based on magnetic signals obtained using the MSR. In other words, the center point in a 2D magnetic field contour plot corresponding to the actual position of magnetic markers was estimated by tracking the errors between pre-defined reference models and measured magnetic signals. The algorithm proposed in this study was validated by experimental measurements using a test vehicle on a pilot network of roads. From the results, the positioning error was found to be less than 0.04 m on average in an operational test.

  3. An improved current control scheme for grid-connected DG unit based distribution system harmonic compensation

    DEFF Research Database (Denmark)

    He, Jinwei; Wei Li, Yun; Wang, Xiongfei;

    2013-01-01

    In order to utilize DG unit interfacing converters to actively compensate distribution system harmonics, this paper proposes an enhanced current control approach. It seamlessly integrates system harmonic mitigation capabilities with the primary DG power generation function. As the proposed curren...

  4. Eight month post program completion; change in risk factors for chronic disease amongst participants in a four-month pedometer-based workplace health program

    DEFF Research Database (Denmark)

    Freak-Poli, Rosanne; Wolfe, Rory; Brand, Margaret

    2013-01-01

    measured waist circumference at twelve-months indicated that the significant improvements observed immediately after the health program could not be sustained. Approximately half of those not meeting guidelines for physical activity, waist circumference and blood pressure at baseline, were meeting......OBJECTIVE: To evaluate whether participation in a four-month, pedometer-based, physical activity, workplace health program is associated with long-term sustained improvements in risk factors for type 2 diabetes and cardiovascular disease, eight-months after the completion of the program. DESIGN...... guidelines at twelve-months. CONCLUSIONS: Participation in this four-month, pedometer-based, physical activity, workplace health program was associated with sustained improvements chronic disease risk factors at twelve-months. These results indicate that such programs can have a long-term benefit and thus...

  5. Real time algorithm temperature compensation in tunable laser / VCSEL based WDM-PON system

    DEFF Research Database (Denmark)

    Iglesias Olmedo, Miguel; Rodes Lopez, Roberto; Pham, Tien Thang

    2012-01-01

    We report on a real time experimental validation of a centralized algorithm for temperature compensation of tunable laser/VCSEL at ONU and OLT, respectively. Locking to a chosen WDM channel is shown for temperature changes over 40°C.......We report on a real time experimental validation of a centralized algorithm for temperature compensation of tunable laser/VCSEL at ONU and OLT, respectively. Locking to a chosen WDM channel is shown for temperature changes over 40°C....

  6. 26 CFR 1.401(e)-5 - Limitation of contribution and benefit bases to first $100,000 of annual compensation in case of...

    Science.gov (United States)

    2010-04-01

    ... Limitation of contribution and benefit bases to first $100,000 of annual compensation in case of plans... 26 Internal Revenue 5 2010-04-01 2010-04-01 false Limitation of contribution and benefit bases to first $100,000 of annual compensation in case of plans covering self-employed individuals. 1.401(e)-5...

  7. A Conservation-Based Approach to Compensation for Livestock Depredation: The Florida Panther Case Study.

    Directory of Open Access Journals (Sweden)

    Caitlin E Jacobs

    Full Text Available Calf (Bos taurus depredation by the federally endangered Florida panther (Puma concolor coryi on ranches in southwest Florida is an important issue because ranches represent mixed landscapes that provide habitat critical to panther recovery. The objectives of this study were to (1 quantify calf depredation by panthers on two ranches in southwest Florida, and (2 develop a habitat suitability model to evaluate the quality of panther hunting habitat on ranchlands, assess whether the model could predict predation risk to calves, and discuss its potential to be incorporated into an incentive-based compensation program. We ear-tagged 409 calves with VHF transmitters on two ranches during 2011-2013 to document calf mortality. We developed a model to evaluate the quality of panther hunting habitat on private lands in southwest Florida using environmental variables obtained from the Florida Natural Areas Inventory (FNAI Cooperative Landcover Database and nocturnal GPS locations of panthers provided by the Florida Fish and Wildlife Conservation Commission (FWC. We then tested whether the model could predict the location of calf depredation sites. Tagged calf loss to panthers varied between the two ranches (0.5%/yr to 5.3%/yr and may have been influenced by the amount of panther hunting habitat on each ranch as the ranch that experienced higher depredation rates contained a significantly higher probability of panther presence. Depredation sites of tagged calves had a significantly greater probability of panther presence than depredation sites of untagged calves that were found by ranchers in open pastures. This suggests that there may be more calves killed in high risk environments than are being found and reported by ranchers and that panthers can hunt effectively in open environments. It also suggests that the model may provide a means for evaluating the quality of panther hunting habitat and the corresponding risk of depredation to livestock across the

  8. A Conservation-Based Approach to Compensation for Livestock Depredation: The Florida Panther Case Study.

    Science.gov (United States)

    Jacobs, Caitlin E; Main, Martin B

    2015-01-01

    Calf (Bos taurus) depredation by the federally endangered Florida panther (Puma concolor coryi) on ranches in southwest Florida is an important issue because ranches represent mixed landscapes that provide habitat critical to panther recovery. The objectives of this study were to (1) quantify calf depredation by panthers on two ranches in southwest Florida, and (2) develop a habitat suitability model to evaluate the quality of panther hunting habitat on ranchlands, assess whether the model could predict predation risk to calves, and discuss its potential to be incorporated into an incentive-based compensation program. We ear-tagged 409 calves with VHF transmitters on two ranches during 2011-2013 to document calf mortality. We developed a model to evaluate the quality of panther hunting habitat on private lands in southwest Florida using environmental variables obtained from the Florida Natural Areas Inventory (FNAI) Cooperative Landcover Database and nocturnal GPS locations of panthers provided by the Florida Fish and Wildlife Conservation Commission (FWC). We then tested whether the model could predict the location of calf depredation sites. Tagged calf loss to panthers varied between the two ranches (0.5%/yr to 5.3%/yr) and may have been influenced by the amount of panther hunting habitat on each ranch as the ranch that experienced higher depredation rates contained a significantly higher probability of panther presence. Depredation sites of tagged calves had a significantly greater probability of panther presence than depredation sites of untagged calves that were found by ranchers in open pastures. This suggests that there may be more calves killed in high risk environments than are being found and reported by ranchers and that panthers can hunt effectively in open environments. It also suggests that the model may provide a means for evaluating the quality of panther hunting habitat and the corresponding risk of depredation to livestock across the landscape. We

  9. Network delay predictive compensation based on time-delay modelling as disturbance

    Science.gov (United States)

    Florin Caruntu, Constantin; Lazar, Corneliu

    2014-10-01

    In this paper, a control design methodology that can assure the closed-loop performances of a physical plant, while compensating the network-induced time-varying delays, is proposed. First, the error caused by the time-varying delays is modelled as a disturbance and a novel method of bounding the disturbance is proposed. Second, a robust one step ahead predictive controller based on flexible control Lyapunov functions is designed, which explicitly takes into account the bounds of the disturbances and guarantees also the input-to-state stability of the system in a non-conservative way. The methodology was tested on a vehicle drivetrain controlled through controller area network, with the aim of damping driveline oscillations. The comparison with a proportional-integral-derivative (PID) controller using TrueTime simulator shows that the proposed control scheme can outperform classical controllers and it can handle the performance/physical constraints. Moreover, the handling of the strict limitations on the computational complexity was tested using a real-time test-bench.

  10. Application of geometry based hysteresis modelling in compensation of hysteresis of piezo bender actuator

    Science.gov (United States)

    Milecki, Andrzej; Pelic, Marcin

    2016-10-01

    This paper presents results of studies of an application of a new method of piezo bender actuators modelling. A special hysteresis simulation model was developed and is presented. The model is based on a geometrical deformation of main hysteresis loop. The piezoelectric effect is described and the history of the hysteresis modelling is briefly reviewed. Firstly, a simple model for main loop modelling is proposed. Then, a geometrical description of the non-saturated hysteresis is presented and its modelling method is introduced. The modelling makes use of the function describing the geometrical shape of the two hysteresis main curves, which can be defined theoretically or obtained by measurement. These main curves are stored in the memory and transformed geometrically in order to obtain the minor curves. Such model was prepared in the Matlab-Simulink software, but can be easily implemented using any programming language and applied in an on-line controller. In comparison to the other known simulation methods, the one presented in the paper is easy to understand, and uses simple arithmetical equations, allowing to quickly obtain the inversed model of hysteresis. The inversed model was further used for compensation of a non-saturated hysteresis of the piezo bender actuator and results have also been presented in the paper.

  11. ARTIFICIAL NEURAL NETWORK CONTROLLER BASED DISTRIBUTION STATIC COMPENSATOR FOR VOLTAGE SAG MITIGATION

    Directory of Open Access Journals (Sweden)

    D. Rajasekaran

    2013-01-01

    Full Text Available Switching of loads, capacitors, along with the proliferation of power electronics equipment, non-linear loads in industrial, commercial and domestic applications have lead to power quality issues in the distribution system. Power quality issues such as voltage sag, voltage swell and harmonics, which are certainly major concerning issues in the present era. These issues can lead to failure or malfunction of the many sensitive loads connected to the distribution system, thus incurring a high cost for end users. Power quality problems are solved by advanced custom power devices. This study presents how the custom power device Distribution Static Compensator (D-STATCOM is used to mitigate voltage sag and voltage harmonics in distribution system. Artificial Neural Network (ANN controller based D-STATCOM is simulated in MATLAB-SIMULINK environment. Prototype model for single phase D-STATCOM is developed to verify the results. The simulation and hardware results show clearly the performance of the D-STATCOM in mitigating voltage sag and voltage harmonics in distribution system.

  12. Air temperature measurements based on the speed of sound to compensate long distance interferometric measurements

    Directory of Open Access Journals (Sweden)

    Astrua Milena

    2014-01-01

    Full Text Available A method to measure the real time temperature distribution along an interferometer path based on the propagation of acoustic waves is presented. It exploits the high sensitivity of the speed of sound in air to the air temperature. In particular, it takes advantage of a special set-up where the generation of the acoustic waves is synchronous with the amplitude modulation of a laser source. A photodetector converts the laser light to an electronic signal considered as reference, while the incoming acoustic waves are focused on a microphone and generate a second signal. In this condition, the phase difference between the two signals substantially depends on the temperature of the air volume interposed between the sources and the receivers. The comparison with the traditional temperature sensors highlighted the limit of the latter in case of fast temperature variations and the advantage of a measurement integrated along the optical path instead of a sampling measurement. The capability of the acoustic method to compensate the interferometric distance measurements due to air temperature variations has been demonstrated for distances up to 27 m.

  13. Enhanced sensitivity of temperature-compensated SAW-based current sensor using the magnetostrictive effect

    Science.gov (United States)

    Wang, Wen; Jia, Yana; Liu, Xinlu; Liang, Yong; Xue, Xufeng; Du, Zaofu

    2017-02-01

    A temperature-compensated surface acoustic wave (SAW)-based current sensor was proposed in this contribution, composed of a sensor chip made by SAW delay line patterns on a SiO2/128° YX LiNbO3 piezoelectric substrate, a magnetostrictive FeCo film deposited on the SAW propagation path, and a corresponding differential oscillation configuration. The FeCo coating produced magnetostrictive strain under the magnetic field generated by the applied current, leading to linearity changes in the SAW propagation in the form of velocity change. The corresponding differential oscillation frequency shift was used to evaluate the tested current. By solving the coupled electromechanical field equation in a layered structure while considering the magnetostrictive effect, the optimal FeCo film thickness, and sensor operation frequency yielding high current sensitivity, were determined, and then confirmed experimentally by evaluating the developed SAW current sensor system utilizing a Helmholtz coil. A high sensitivity of 16.6 KHz A-1 (8.3 KHz m-1 T-1), excellent linearity, and lower detection limit (˜0.2 mA) were achieved with our 300 MHz SAW sensor with a 500 nm FeCo coating and aspect ratio of 2:1.

  14. Adaptive robust motion trajectory tracking control of pneumatic cylinders with LuGre model-based friction compensation

    Science.gov (United States)

    Meng, Deyuan; Tao, Guoliang; Liu, Hao; Zhu, Xiaocong

    2014-07-01

    Friction compensation is particularly important for motion trajectory tracking control of pneumatic cylinders at low speed movement. However, most of the existing model-based friction compensation schemes use simple classical models, which are not enough to address applications with high-accuracy position requirements. Furthermore, the friction force in the cylinder is time-varying, and there exist rather severe unmodelled dynamics and unknown disturbances in the pneumatic system. To deal with these problems effectively, an adaptive robust controller with LuGre model-based dynamic friction compensation is constructed. The proposed controller employs on-line recursive least squares estimation (RLSE) to reduce the extent of parametric uncertainties, and utilizes the sliding mode control method to attenuate the effects of parameter estimation errors, unmodelled dynamics and disturbances. In addition, in order to realize LuGre model-based friction compensation, the modified dual-observer structure for estimating immeasurable friction internal state is developed. Therefore, a prescribed motion tracking transient performance and final tracking accuracy can be guaranteed. Since the system model uncertainties are unmatched, the recursive backstepping design technology is applied. In order to solve the conflicts between the sliding mode control design and the adaptive control design, the projection mapping is used to condition the RLSE algorithm so that the parameter estimates are kept within a known bounded convex set. Finally, the proposed controller is tested for tracking sinusoidal trajectories and smooth square trajectory under different loads and sudden disturbance. The testing results demonstrate that the achievable performance of the proposed controller is excellent and is much better than most other studies in literature. Especially when a 0.5 Hz sinusoidal trajectory is tracked, the maximum tracking error is 0.96 mm and the average tracking error is 0.45 mm. This

  15. PET Motion Compensation for Radiation Therapy Using a CT-Based Mid-Position Motion Model: Methodology and Clinical Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kruis, Matthijs F.; Kamer, Jeroen B. van de; Houweling, Antonetta C.; Sonke, Jan-Jakob; Belderbos, José S.A.; Herk, Marcel van, E-mail: m.v.herk@nki.nl

    2013-10-01

    Purpose: Four-dimensional positron emission tomography (4D PET) imaging of the thorax produces sharper images with reduced motion artifacts. Current radiation therapy planning systems, however, do not facilitate 4D plan optimization. When images are acquired in a 2-minute time slot, the signal-to-noise ratio of each 4D frame is low, compromising image quality. The purpose of this study was to implement and evaluate the construction of mid-position 3D PET scans, with motion compensated using a 4D computed tomography (CT)-derived motion model. Methods and Materials: All voxels of 4D PET were registered to the time-averaged position by using a motion model derived from the 4D CT frames. After the registration the scans were summed, resulting in a motion-compensated 3D mid-position PET scan. The method was tested with a phantom dataset as well as data from 27 lung cancer patients. Results: PET motion compensation using a CT-based motion model improved image quality of both phantoms and patients in terms of increased maximum SUV (SUV{sub max}) values and decreased apparent volumes. In homogenous phantom data, a strong relationship was found between the amplitude-to-diameter ratio and the effects of the method. In heterogeneous patient data, the effect correlated better with the motion amplitude. In case of large amplitudes, motion compensation may increase SUV{sub max} up to 25% and reduce the diameter of the 50% SUV{sub max} volume by 10%. Conclusions: 4D CT-based motion-compensated mid-position PET scans provide improved quantitative data in terms of uptake values and volumes at the time-averaged position, thereby facilitating more accurate radiation therapy treatment planning of pulmonary lesions.

  16. Beam splitting target reflector based compensation for angular drift of laser beam in laser autocollimation of measuring small angle deviations.

    Science.gov (United States)

    Zhu, Fan; Tan, Jiubin; Cui, Jiwen

    2013-06-01

    Beam splitting target reflector based compensation for the angular drift of laser beam in laser autocollimation is proposed in this article to improve the measurement accuracy and stability of small angle deviations. A beam splitting target reflector is used to replace the plane mirror in laser autocollimation to generate a reference beam when returning the measurement beam. The reference beam and measurement beam have the same angular drift, but have different sensitivities to the rotation angle of the reflector due to the unique characteristics of the reflector. Thus, the angular drift of laser beam in laser autocollimation can be compensated in real time by using the drift of reference beam. Experimental results indicate that an output stability of 0.085 arc sec in 2 h can be achieved after compensation. And a measurement accuracy of ±0.032 arc sec can be obtained over the range of ±1190 arc sec with an effective resolution of 0.006 arc sec. It is confirmed that the compensation method for the angular drift of laser beam is necessary for improving the measurement accuracy and stability in laser autocollimation.

  17. Beam splitting target reflector based compensation for angular drift of laser beam in laser autocollimation of measuring small angle deviations

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Fan; Tan Jiubin; Cui Jiwen [Center of Ultra-precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin 150080 (China)

    2013-06-15

    Beam splitting target reflector based compensation for the angular drift of laser beam in laser autocollimation is proposed in this article to improve the measurement accuracy and stability of small angle deviations. A beam splitting target reflector is used to replace the plane mirror in laser autocollimation to generate a reference beam when returning the measurement beam. The reference beam and measurement beam have the same angular drift, but have different sensitivities to the rotation angle of the reflector due to the unique characteristics of the reflector. Thus, the angular drift of laser beam in laser autocollimation can be compensated in real time by using the drift of reference beam. Experimental results indicate that an output stability of 0.085 arc sec in 2 h can be achieved after compensation. And a measurement accuracy of {+-}0.032 arc sec can be obtained over the range of {+-}1190 arc sec with an effective resolution of 0.006 arc sec. It is confirmed that the compensation method for the angular drift of laser beam is necessary for improving the measurement accuracy and stability in laser autocollimation.

  18. Online absolute pose compensation and steering control of industrial robot based on six degrees of freedom laser measurement

    Science.gov (United States)

    Yang, Juqing; Wang, Dayong; Fan, Baixing; Dong, Dengfeng; Zhou, Weihu

    2017-03-01

    In-situ intelligent manufacturing for large-volume equipment requires industrial robots with absolute high-accuracy positioning and orientation steering control. Conventional robots mainly employ an offline calibration technology to identify and compensate key robotic parameters. However, the dynamic and static parameters of a robot change nonlinearly. It is not possible to acquire a robot's actual parameters and control the absolute pose of the robot with a high accuracy within a large workspace by offline calibration in real-time. This study proposes a real-time online absolute pose steering control method for an industrial robot based on six degrees of freedom laser tracking measurement, which adopts comprehensive compensation and correction of differential movement variables. First, the pose steering control system and robot kinematics error model are constructed, and then the pose error compensation mechanism and algorithm are introduced in detail. By accurately achieving the position and orientation of the robot end-tool, mapping the computed Jacobian matrix of the joint variable and correcting the joint variable, the real-time online absolute pose compensation for an industrial robot is accurately implemented in simulations and experimental tests. The average positioning error is 0.048 mm and orientation accuracy is better than 0.01 deg. The results demonstrate that the proposed method is feasible, and the online absolute accuracy of a robot is sufficiently enhanced.

  19. A Study of Dispersion Compensation of Polarization Multiplexing-Based OFDM-OCDMA for Radio-over-Fiber Transmissions

    Directory of Open Access Journals (Sweden)

    Chih-Ta Yen

    2016-09-01

    Full Text Available Chromatic dispersion from optical fiber is the most important problem that produces temporal skews and destroys the rectangular structure of code patterns in the spectra-amplitude-coding-based optical code-division multiple-access (SAC-OCDMA system. Thus, the balance detection scheme does not work perfectly to cancel multiple access interference (MAI and the system performance will be degraded. Orthogonal frequency-division multiplexing (OFDM is the fastest developing technology in the academic and industrial fields of wireless transmission. In this study, the radio-over-fiber system is realized by integrating OFDM and OCDMA via polarization multiplexing scheme. The electronic dispersion compensation (EDC equalizer element of OFDM integrated with the dispersion compensation fiber (DCF is used in the proposed radio-over-fiber (RoF system, which can efficiently suppress the chromatic dispersion influence in long-haul transmitted distance. A set of length differences for 10 km-long single-mode fiber (SMF and 4 km-long DCF is to verify the compensation scheme by relative equalizer algorithms and constellation diagrams. In the simulation result, the proposed dispersion mechanism successfully compensates the dispersion from SMF and the system performance with dispersion equalizer is highly improved.

  20. A Study of Dispersion Compensation of Polarization Multiplexing-Based OFDM-OCDMA for Radio-over-Fiber Transmissions.

    Science.gov (United States)

    Yen, Chih-Ta; Chen, Wen-Bin

    2016-09-07

    Chromatic dispersion from optical fiber is the most important problem that produces temporal skews and destroys the rectangular structure of code patterns in the spectra-amplitude-coding-based optical code-division multiple-access (SAC-OCDMA) system. Thus, the balance detection scheme does not work perfectly to cancel multiple access interference (MAI) and the system performance will be degraded. Orthogonal frequency-division multiplexing (OFDM) is the fastest developing technology in the academic and industrial fields of wireless transmission. In this study, the radio-over-fiber system is realized by integrating OFDM and OCDMA via polarization multiplexing scheme. The electronic dispersion compensation (EDC) equalizer element of OFDM integrated with the dispersion compensation fiber (DCF) is used in the proposed radio-over-fiber (RoF) system, which can efficiently suppress the chromatic dispersion influence in long-haul transmitted distance. A set of length differences for 10 km-long single-mode fiber (SMF) and 4 km-long DCF is to verify the compensation scheme by relative equalizer algorithms and constellation diagrams. In the simulation result, the proposed dispersion mechanism successfully compensates the dispersion from SMF and the system performance with dispersion equalizer is highly improved.

  1. An Efficient Compensation Method for Limited-View Photoacoustic Imaging Reconstruction Based on Gerchberg–Papoulis Extrapolation

    Directory of Open Access Journals (Sweden)

    Jin Wang

    2017-05-01

    Full Text Available The reconstruction for limited-view scanning, though often the case in practice, has remained a difficult issue for photoacoustic imaging (PAI. The incompleteness of sampling data will cause serious artifacts and fuzziness in those missing views and it will heavily affect the quality of the image. To solve the problem of limited-view PAI, a compensation method based on the Gerchberg–Papoulis (GP extrapolation is applied into PAI. Based on the known data, missing detectors elements are estimated and the image in the missing views is then compensated using the Fast Fourier Transform (FFT. To accelerate the convergence speed of the algorithm, the total variation (TV-based iterative algorithm is incorporated into the GP extrapolation-based FFT-utilized compensation method (TV-GPEF. The effective variable splitting and Barzilai–Borwein based method is adopted to solve the optimization problem. Simulations and in vitro experiments for both limited-angle circular scanning and straight-line scanning are conducted to validate the proposed algorithm. Results show that the proposed algorithm can greatly suppress the artifacts caused by the missing views and enhance the edges and the details of the image. It can be indicated that the proposed TV-GPEF algorithm is efficient for limited-view PAI.

  2. Error compensation on precision machine tool servo control system based on digital concave filter

    Institute of Scientific and Technical Information of China (English)

    王立松; 苏宝库; 张晶; 董申

    2001-01-01

    It is concluded from the results of testing the frequency characteristics of the sub-micron precision machine tool servo control system, that the existence of several oscillating modalities is the main factor that affects the performance of the control system. To compensate for this effect, several concave filters are utilized in the system to improve the control accuracy. The feasibility of compensating for several oscillating modalities with a single concave filter is also studied. By applying a modified Butterworth concave filter to the practical system, the maximum stable state output error remains under + 10 nm in the closed-loop positioning system.

  3. School-Based Interventions for Anxious Children: 3-, 6-, and 12-Month Follow-Ups

    Science.gov (United States)

    Bernstein, Gail A.; Bernat, Debra H.; Victor, Andrea M.; Layne, Ann E.

    2008-01-01

    The study followed participants aged 7 to 11 years from a previous study that compared three school-based cognitive-behavioral therapy (CBT) interventions for anxious children to determine long-term post-treatment benefits. Results indicate school-based CBT decreases anxiety symptoms up to 12 months post-treatment.

  4. Faraday isolator based on a TSAG single crystal with compensation of thermally induced depolarization inside magnetic field

    Science.gov (United States)

    Snetkov, Ilya; Palashov, Oleg

    2015-04-01

    A Faraday isolator based on a terbium scandium aluminum garnet (TSAG) single crystal with compensation of thermally induced depolarization inside magnetic field was demonstrated. An isolation ratio of 32 dB at 350 W cw laser radiation power was achieved. Thermally induced depolarization and thermal lens were studied and compared with similar thermal effects arising in the widely used terbium gallium garnet crystal (TGG) for the first time.

  5. Networked Control System Time-Delay Compensation Based on Time-Delay Prediction and Improved Implicit GPC

    OpenAIRE

    Zhong-Da Tian; Shu-Jiang Li; Yan-Hong Wang; Hong-Xia Yu

    2015-01-01

    The random time delay in a networked control system can usually deteriorate the control performance and stability of the networked control system. In order to solve this problem, this paper puts forward a networked control system random time-delay compensation method based on time-delay prediction and improved implicit generalized predictive control (GPC). The least squares support vector machine is used to predict the future time delay of network. The parameters of the least squares support...

  6. 38 CFR 4.16 - Total disability ratings for compensation based on unemployability of the individual.

    Science.gov (United States)

    2010-07-01

    ... to meet the percentage standards set forth in paragraph (a) of this section. The rating board will... disabilities, there shall be at least one disability ratable at 40 percent or more, and sufficient additional... boards should submit to the Director, Compensation and Pension Service, for extra-schedular...

  7. Compensability index for compensation radiotherapy after treatment interruptions

    Directory of Open Access Journals (Sweden)

    Putora Paul

    2012-12-01

    Full Text Available Abstract Background The goal of our work was to develop a simple method to evaluate a compensation treatment after unplanned treatment interruptions with respect to their tumour- and normal tissue effect. Methods We developed a software tool in java programming language based on existing recommendations to compensate for treatment interruptions. In order to express and visualize the deviations from the originally planned tumour and normal tissue effects we defined the compensability index. Results The compensability index represents an evaluation of the suitability of compensatory radiotherapy in a single number based on the number of days used for compensation and the preference of preserving the originally planned tumour effect or not exceeding the originally planned normal tissue effect. An automated tool provides a method for quick evaluation of compensation treatments. Conclusions The compensability index calculation may serve as a decision support system based on existing and established recommendations.

  8. 18-Months Operation of Lunar-based Ultraviolet Telescope: A Highly Stable Photometric Performance

    CERN Document Server

    Wang, J; Han, X H; Cai, H B; Cao, L; Deng, J S; Qiu, Y L; Wang, S; Wei, J Y; Hu, J Y

    2015-01-01

    We here report the photometric performance of Lunar-based Ultraviolet telescope (LUT), the first robotic telescope working on the Moon, for its 18-months operation. In total, 17 IUE standards have been observed in 51 runs until June 2015, which returns a highly stable photometric performance during the past 18 months (i.e., no evolution of photometric performance with time). The magnitude zero point is determined to be $17.53\\pm0.05$ mag, which is not only highly consistent with the results based on its first 6-months operation, but also independent on the spectral type of the standard from which the magnitude zero point is determined. The implications of this stable performance is discussed, and is useful for next generation lunar-based astronomical observations.

  9. Compensation of skull motion and breathing motion in CT using data-based and image-based metrics, respectively

    Science.gov (United States)

    Bruder, H.; Rohkohl, C.; Stierstorfer, K.; Flohr, T.

    2016-03-01

    We present a novel reconstruction for motion correction of non-cardiac organs. With non-cooperative patients or in emergency case, breathing motion or motion of the skull may compromise image quality. Our algorithm is based on the optimization of either motion artefact metrics or data-driven metrics. This approach was successfully applied in cardiac CTA [1]. While motion correction of the coronary vessels requires a local motion model, global motion models are sufficient for organs like the lung or the skull. The parameter vector for the global affine motion is estimated iteratively, using the open source optimization library NLOPT. The image is updated using motion compensated reconstruction in each of the iterations. Evaluation of the metric value, e.g. the image entropy, provides information for the next iteration loop. After reaching the fixed point of the iteration, the final motion parameters are used for a motion-compensated full quality reconstruction. In head imaging the motion model is based on translation and rotation, in thoracic imaging the rotation is replaced by non-isotropic scaling in all three dimensions. We demonstrate the efficiency of the method in thoracic imaging by evaluating PET-CT data from free-breathing patients. In neuro imaging, data from stroke patients showing skull tremor were analyzed. It was shown that motion artefacts can be largely reduced and spatial resolution was restored. In head imaging, similar results can be obtained using motion artefact metrics or data-driven metrics. In case of image-based metrics, the entropy of the image proved to be superior. Breathing motion could also be significantly reduced using entropy metric. However, in this case data driven metrics cannot be applied because the line integrals associated to the ROI of the lung have to be computed using the local ROI mechanism [2] It was shown that the lung signal is corrupted by signals originating from the complement of the lung. Thus a meaningful

  10. High-speed tunable photonic crystal fiber-based femtosecond soliton source without dispersion pre-compensation

    Directory of Open Access Journals (Sweden)

    Martín E. Masip

    2012-02-01

    Full Text Available We present a high-speed wavelength tunable photonic crystal fiber-based source capable of generating tunable femtosecond solitons in the infrared region. Through measurements and numerical simulation, we show that both the pulsewidth and the spectral width of the output pulses remain nearly constant over the entire tuning range from 860 to 1160 nm. This remarkable behavior is observed even when pump pulses are heavily chirped (7400 fs^2, which allows to avoid bulky compensation optics, or the use of another fiber, for dispersion compensation usually required by the tuning device. Received: 7 July 2011, Accepted: 1 February 2012; Edited by: A. Goñi; Reviewed by: J. Chavez Boggio, Leibniz Institut fur Astrophysik Potsdam, Germany; DOI: http://dx.doi.org/10.4279/PIP.040001 Cite as: M. Caldarola, V. A. Bettachini, A. A. Rieznik, P. G. Konig, M. E. Masip, D. F. Grosz, A. V. Bragas, Papers in Physics 4, 040001 (2012

  11. MULTI-RESOLUTION MOTION ESTIMATION AND COMPENSATION BASED ON ADJACENT PREDICTION OF FRAME DIFFERENCE IN WAVELET DOMAIN

    Institute of Scientific and Technical Information of China (English)

    Tang Guowei; Gu Guochang

    2009-01-01

    Aiming at the higher bit-rate occupation of motion vector encoding and more time load of full-searching strategies,a multi-resolution motion estimation and compensation algorithm based on adjacent prediction of frame difference was proposed.Differential motion detection was employed to image sequences and proper threshold was adopted to identify the connected region.Then the motion region was extracted to carry out motion estimation and motion compensation on it.The experiment results show that the encoding efficiency of motion vector is promoted,the complexity of motion es timation is reduced and the quality of the reconstruction image at the same bit-rate as Multi-Reso lution Motion Estimation (MRME) is improved.

  12. A 9-month follow-up of a 3-month web-based alcohol treatment program using intensive asynchronous therapeutic support.

    NARCIS (Netherlands)

    Postel, Marloes Gerda; ter Huurne, E.D.; de Haan, H.A.; van der Palen, Jacobus Adrianus Maria; de Jong, Cor A.J.

    2015-01-01

    Background: Web-based alcohol interventions have demonstrated efficacy in randomized controlled trials. However, most studies have involved self-help interventions without therapeutic support. Objectives: To examine the results of a 3-month web-based alcohol treatment program using intensive,

  13. A 9-month follow-up of a 3-month web-based alcohol treatment program using intensive asynchronous therapeutic support

    NARCIS (Netherlands)

    Postel, M.G.; Huurne, E.D. ter; Haan, H.A. de; Palen, J.A.M. van der; Jong, C.A.J. de

    2015-01-01

    Background: Web-based alcohol interventions have demonstrated efficacy in randomized controlled trials. However, most studies have involved self-help interventions without therapeutic support. Objectives: To examine the results of a 3-month web-based alcohol treatment program using intensive,

  14. A 9-month follow-up of a 3-month web-based alcohol treatment program using intensive asynchronous therapeutic support.

    NARCIS (Netherlands)

    Postel, M.G.; Huurne, ter E.D.; Haan, de H.A.; Palen, van der Job; Jong, de Cor A.J.

    2015-01-01

    Background: Web-based alcohol interventions have demonstrated efficacy in randomized controlled trials. However, most studies have involved self-help interventions without therapeutic support. Objectives: To examine the results of a 3-month web-based alcohol treatment program using intensive, asynch

  15. Coordinating a multi-retailer decentralized distribution system with random demand based on buyback and compensation contracts

    Directory of Open Access Journals (Sweden)

    Jinyu Ren

    2015-01-01

    Full Text Available Purpose: The purpose of this paper is to set up the coordinating mechanism for a decentralized distribution system consisting of a manufacturer and multiple independent retailers by means of contracts. It is in the two-stage supply chain system that all retailers sell an identical product made by the manufacturer and determine their order quantities which directly affect the expected profit of the supply chain with random demand. Design/methodology/approach: First comparison of the optimal order quantities in the centralized and decentralized system shows that the supply chain needs coordination. Then the coordination model is given based on buyback cost and compensation benefit. Finally the coordination mechanism is set up in which the manufacturer as the leader uses a buyback policy to incentive these retailers and the retailers pay profit returns to compensate the manufacturer. Findings: The results of a numerical example show that the perfect supply chain coordination and the flexible allocation of the profit can be achieved in the multi-retailer supply chain by the buyback and compensation contracts. Research limitations: The results based on assumptions might not completely hold in practice and the paper only focuses on studying a single product in two-stage supply chain. Practical implications: The coordination mechanism is applicable to a realistic supply chain under a private information setting and the research results is the foundation of further developing the coordination mechanism for a realistic multi-stage supply chain system with more products. Originality/value: This paper focused on studying the coordination mechanism for a decentralized multi-retailer supply chain by the joint application of the buyback and compensation contracts. Furthermore the perfect supply chain coordination and the flexible allocation of the profit are achieved.

  16. Novel temperature modeling and compensation method for bias of ring laser gyroscope based on least-squares support vector machine

    Institute of Scientific and Technical Information of China (English)

    Xudong Yu; Yu Wang; Guo Wei; Pengfei Zhang; Xingwu Long

    2011-01-01

    Bias of ring-laser-gyroscope (RLG) changes with temperature in a nonlinear way. This is an important restraining factor for improving the accuracy of RLG. Considering the limitations of least-squares regression and neural network, we propose a new method of temperature compensation of RLG bias-building function regression model using least-squares support vector machine (LS-SVM). Static and dynamic temperature experiments of RLG bias are carried out to validate the effectiveness of the proposed method. Moreover,the traditional least-squares regression method is compared with the LS-SVM-based method. The results show the maximum error of RLG bias drops by almost two orders of magnitude after static temperature compensation, while bias stability of RLG improves by one order of magnitude after dynamic temperature compensation. Thus, the proposed method reduces the influence of temperature variation on the bias of the RLG effectively and improves the accuracy of the gyro scope considerably.%@@ Bias of ring-laser-gyroscope (RLG) changes with temperature in a nonlinear way.This is an important restraining factor for improving the accuracy of RLG.Considering the limitations of least-squares regression and neural network, we propose a new method of temperature compensation of RLG bias-building function regression model using least-squares support vector machine (LS-SVM).Static and dynamic temperature experiments of RLG bias are carried out to validate the effectiveness of the proposed method.Moreover,the traditional least-squares regression method is compared with the LS-SVM-based method.

  17. Three Evidence Based Methods to Compensate for a Lack of Subject Background when Ordering Chemistry Monographs

    Directory of Open Access Journals (Sweden)

    Robert A. Wright

    2008-09-01

    Full Text Available Objective – The aim of this article is to present evidence based methods for the selection of chemistry monographs, particularly for librarians lacking a background in chemistry. These methods will be described in detail, their practical application illustrated, and their efficacy tested by analyzing circulation data.Methods – Two hundred and ninety-five chemistry monographs were selected between 2005 and 2007 using rigorously-applied evidence based methods involving the Library's integrated library system (ILS, Google, and SciFinder Scholar. The average circulation rate of this group of monographs was compared to the average circulation rate of 254 chemistry monographs selected between 2002 and 2004 when the methods were not used or were in an incomplete state of development.Results – Circulations/month were on average 9% greater in the cohort of monographs selected with the rigorously-applied evidence based methods. Further statistical analysis, however, finds that this result can not be attributed to the different application of these methods. Conclusion – The methods discussed in this article appear to provide an evidence base for the selection of chemistry monographs, but their application does not change circulation rates in a statistically significant way. Further research is needed to determine if this lack of statistical significance is real or a product of the organic development and application of these methods over time, making definitive comparisons difficult.

  18. Nonuniformity compensation methods for the thermal imager based on uncooled focal plane array

    Science.gov (United States)

    Wu, Cheng; Su, Junhong

    2000-05-01

    Because of the detector material, manufacturing technology and optical system, there is a obvious signal responsivity variation in sensor elements of uncooled focal plane array (UFPA), that is same as the cooled FPA. This variations results in a severe fixed pattern noise. There have been a lot of varied ways to compensate the nonuniformity of FPA detectors now. This paper briefly describes several main nonuniformity compensation (NUC) methods discussed below, and considering the properties of UFPA detectors, the precision and rate of NUC, a practical NUC methods applying to UFPA is given. The aim is to simplify the hardware and software of NUC for UFPA, and to satisfy the requests of use in the real world simultaneously.

  19. Assesment and Analyze Hybride Control System in Distribution Static Synchronous Compensator Based Current Source Converter

    Directory of Open Access Journals (Sweden)

    Seyed Mohammad Ali Zanjani

    2011-10-01

    Full Text Available With the rapid technology advancement in control processes, electric utilities are experiencing more demanding requirements on the power quality from the large industrial power consumers. For achieved this purpose use of FACTS devices. One of kind compensator is D-Statcom, using in distribution system for conquest of power quality problem. This paper presents system modeling and control design techniques of distribution static synchronous compensator. For reach an optimal design, using a hybride state-feedback and d-q control systems. Using direct sampling on network parameter, than conventional control system, as well as fast dynamic responses are achieved. The derived simulations are tried to verify the result of this paper.

  20. Towards loss compensated and lasing terahertz metamaterials based on optically pumped graphene

    CERN Document Server

    Weis, Peter; Rahm, Marco

    2013-01-01

    It is evidenced by numerical calculations that optically pumped graphene is suitable for compensating inherent loss in terahertz (THz) metamaterials. In a first step, the complex conductivity of graphene under optical pumping is calculated and the proper conditions for terahertz amplification in single layer graphene are determined. It is shown that amplification in graphene occurs for temperatures up to room temperature and for moderate pump intensities when pumped at a telecommunication wavelength $\\lambda=1.5~\\mathrm{\\mu m}$. Furthermore, the amplification properties of graphene are evaluated and discussed at a temperature as low as $T=77~\\mathrm{K}$ and a pump intensity $I=300~\\mathrm{mW/mm^2}$ to investigate the coupling between graphene and a plasmonic split ring resonator (SRR) metamaterial. The contributions of ohmic and dielectric loss mechanisms are studied by full wave simulations. As a result, it is found that the loss of a split-ring resonator metamaterial can be compensated by optically stimulat...

  1. Model Compensation Approach Based on Nonuniform Spectral Compression Features for Noisy Speech Recognition

    Directory of Open Access Journals (Sweden)

    Ning Geng-Xin

    2007-01-01

    Full Text Available This paper presents a novel model compensation (MC method for the features of mel-frequency cepstral coefficients (MFCCs with signal-to-noise-ratio- (SNR- dependent nonuniform spectral compression (SNSC. Though these new MFCCs derived from a SNSC scheme have been shown to be robust features under matched case, they suffer from serious mismatch when the reference models are trained at different SNRs and in different environments. To solve this drawback, a compressed mismatch function is defined for the static observations with nonuniform spectral compression. The means and variances of the static features with spectral compression are derived according to this mismatch function. Experimental results show that the proposed method is able to provide recognition accuracy better than conventional MC methods when using uncompressed features especially at very low SNR under different noises. Moreover, the new compensation method has a computational complexity slightly above that of conventional MC methods.

  2. Evolve the Controller for Static Synchronous Series Compensator Based on Control Strategy of Sen Transformer

    Directory of Open Access Journals (Sweden)

    Raju Jayaraman

    2014-02-01

    Full Text Available Real and Reactive power flow in an alternating current transmission line can be independently controlled by connecting, to the transmission line, a series-compensating voltage, which is variable in magnitude and phase angle. The Static Synchronous Series Compensator (SSSC, a solid-state voltage source inverter (VSC coupled with a transformer, is connected in series with a transmission line. An SSSC injects an almost sinusoidal voltage, of variable magnitude, in series with a transmission line. This injected voltage is almost in quadrature with the line current, thereby emulating an inductive or a capacitive reactance in series with the transmission line. This emulated variable reactance, inserted by the injected voltage source, influences the electric power flow in the transmission line. In this report, an attempt is made to evolve the model of SSSC and VSC with preliminary studies for the controller design.

  3. 20 CFR 404.288 - Recomputing when you are entitled to a monthly pension based on noncovered employment.

    Science.gov (United States)

    2010-04-01

    ... monthly pension based on noncovered employment. 404.288 Section 404.288 Employees' Benefits SOCIAL... monthly pension based on noncovered employment. (a) After entitlement to old-age or disability insurance... later become entitled to a monthly pension based on noncovered employment, we may recompute your primary...

  4. A Modular Cascaded Multilevel Inverter Based Shunt Hybrid Active Power Filter for Selective Harmonic and Reactive Power Compensation Under Distorted/Unbalanced Grid Voltage Conditions

    Directory of Open Access Journals (Sweden)

    T. Demirdelen

    2016-10-01

    Full Text Available In recent years, shunt hybrid active power filters are being increasingly considered as a viable alternative to both passive filters and active power filters for compensating harmonics. In literature, their applications are restricted to balanced systems and low voltage applications and therefore not for industrial applications. This paper investigates the performance of a modular cascaded multilevel inverter based Shunt Hybrid Active Power Filter (SHAPF for reactive power compensation and selective harmonics elimination under distorted/unbalanced grid voltage conditions in medium voltage levels. In the proposed control method, reactive power compensation is achieved successfully with a perceptible amount and the performance results of harmonic compensation are satisfactory. Theoretical analysis and simulation results are obtained from an actual industrial network model in PSCAD. The simulation results are presented for a proposed system in order to demonstrate that the harmonic compensation performance meets the IEEE-519 standard.

  5. Real-time random delay compensation with prediction-based digital redesign.

    Science.gov (United States)

    Zhang, Yongpeng; Cofie, Penrose; Ajuzie, Augustine N; Zhang, Jian; Akujuobi, Cajetan M

    2011-04-01

    Today's technological demands require challenging control solutions such as real-time applications of Networked Control System (NCS). However, due to communication protocol and shared data bus, NCS experiences uncertain and unpredictable time delays in both input and output channels. These delays cause asynchronization between the controller and the plant thereby degrading the performance of closed-loop control systems. To address this problem, this paper proposes to utilize digital redesign technique to provide real-time random delay compensation.

  6. Towards loss compensated and lasing terahertz metamaterials based on optically pumped graphene

    Science.gov (United States)

    Weis, P.; Garcia-Pomar, J. L.; Rahm, M.

    2014-04-01

    It is evidenced by numerical calculations that optically pumped graphene is suitable for compensating inherent loss in terahertz (THz) metamaterials. In a first step, the complex conductivity of graphene under optical pumping is calculated and the proper conditions for terahertz amplification in single layer graphene are determined. It is shown that amplification in graphene occurs for temperatures up to room temperature and for moderate pump intensities when pumped at a telecommunication wavelength $\\lambda=1.5~\\mathrm{\\mu m}$. Furthermore, the amplification properties of graphene are evaluated and discussed at a temperature as low as $T=77~\\mathrm{K}$ and a pump intensity $I=300~\\mathrm{mW/mm^2}$ to investigate the coupling between graphene and a plasmonic split ring resonator (SRR) metamaterial. The contributions of ohmic and dielectric loss mechanisms are studied by full wave simulations. As a result, it is found that the loss of a split-ring resonator metamaterial can be compensated by optically stimulated amplification in graphene. Moreover, it is shown that a hybrid material consisting of asymmetric split-ring resonators and optically pumped graphene can exceed the laser threshold condition and can emit coherent THz radiation at minimum output power levels of $6 0~\\mathrm{nW/mm^2}$. The use of optically pumped graphene is well suited for loss compensation in THz metamaterials and paves the way to new kinds of coherent THz sources.

  7. State Compensation: A No-cost Scheme for Scalable Failure Recovery in Tree-based Overlay Networks

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, D C; Miller, B P

    2006-07-11

    Tree-based overlay networks (TB{bar O}Ns) have become important for scalable data multicast and aggregation. This infrastructure's generality has lead to widespread usage in large scale and widely distributed environments--environments in which reliability must be addressed. This paper presents state compensation, a novel reliability concept for TB{bar O}N environments that avoids explicit state replication (such as checkpoints) for failure recovery by leveraging general properties of TB{bar O}N computations that allow computational state from non-failed processes to compensate for state lost from failed ones. In this paper, we present our state compensation mechanisms, prove sufficient properties of distributed computations that make these mechanisms feasible and show how to derive computation-specific recovery primitives from these properties. We also present a case study of the recovery process. The result is a general TB{bar O}N recovery model that requires no additional storage, network, or computational resources during normal operation.

  8. Thermal-Induced Errors Prediction and Compensation for a Coordinate Boring Machine Based on Time Series Analysis

    Directory of Open Access Journals (Sweden)

    Jun Yang

    2014-01-01

    Full Text Available To improve the CNC machine tools precision, a thermal error modeling for the motorized spindle was proposed based on time series analysis, considering the length of cutting tools and thermal declined angles, and the real-time error compensation was implemented. A five-point method was applied to measure radial thermal declinations and axial expansion of the spindle with eddy current sensors, solving the problem that the three-point measurement cannot obtain the radial thermal angle errors. Then the stationarity of the thermal error sequences was determined by the Augmented Dickey-Fuller Test Algorithm, and the autocorrelation/partial autocorrelation function was applied to identify the model pattern. By combining both Yule-Walker equations and information criteria, the order and parameters of the models were solved effectively, which improved the prediction accuracy and generalization ability. The results indicated that the prediction accuracy of the time series model could reach up to 90%. In addition, the axial maximum error decreased from 39.6 μm to 7 μm after error compensation, and the machining accuracy was improved by 89.7%. Moreover, the X/Y-direction accuracy can reach up to 77.4% and 86%, respectively, which demonstrated that the proposed methods of measurement, modeling, and compensation were effective.

  9. Dense wavelength-division multiplexing dispersion compensators based on chirped and apodized Fibonacci structures: CA-FC(j,n).

    Science.gov (United States)

    Golmohammadi, Saeed; Moravvej-Farshi, Mohammad Kazem; Rostami, Ali; Zarifkar, Abbas

    2008-12-10

    Chromatic dispersion compensation is an essential feature of high speed dense wavelength-division multiplexing (DWDM) systems. We propose a dispersion compensator structure whose characteristics meet the optical DWDM system requirements. The proposed structure is based on Fibonacci quasi-periodic multilayer structures composed of layers with large index differences. Studying the dispersive properties of Fibonacci structures with generation numbers j=3 and 4, and calculating group delay (GD) and group velocity dispersion (GVD) of their reflection bands, we have demonstrated that to have a smooth GD and almost a constant GVD in each band of a DWDM system, one needs not only to suitably chirp the structure refractive index profile, but also must properly apodize it. We also demonstrate the possibility of achieving high slope GDs and large GVDs by means of high order Fibonacci structures with thicker layers. Finally, by varying the layer dimensions and refractive indices as well as Fibonacci's order, one can design DWDM dispersion compensators suitable for distances as long as 220 km.

  10. A 97 dB dynamic range CSA-based readout circuit with analog temperature compensation for MEMS capacitive sensors

    Science.gov (United States)

    Tao, Yin; Chong, Zhang; Huanming, Wu; Qisong, Wu; Haigang, Yang

    2013-11-01

    This paper presents a charge-sensitive-amplifier (CSA) based readout circuit for capacitive microelectro-mechanical-system (MEMS) sensors. A continuous-time (CT) readout structure using the chopper technique is adopted to cancel the low frequency noise and improve the resolution of the readout circuits. An operational trans-conductance amplifier (OTA) structure with an auxiliary common-mode-feedback-OTA is proposed in the fully differential CSA to suppress the chopper modulation induced disturbance at the OTA input terminal. An analog temperature compensation method is proposed, which adjusts the chopper signal amplitude with temperature variation to compensate the temperature drift of the CSA readout sensitivity. The chip is designed and implemented in a 0.35 μm CMOS process and is 2.1 × 2.1 mm2 in area. The measurement shows that the readout circuit achieves 0.9 aF / √Hz capacitive resolution, 97 dB dynamic range in 100 Hz signal bandwidth, and 0.8 mV/fF sensitivity with a temperature drift of 35 ppm/°C after optimized compensation.

  11. Networked Control System Time-Delay Compensation Based on Time-Delay Prediction and Improved Implicit GPC

    Directory of Open Access Journals (Sweden)

    Zhong-Da Tian

    2015-01-01

    Full Text Available The random time delay in a networked control system can usually deteriorate the control performance and stability of the networked control system. In order to solve this problem, this paper puts forward a networked control system random time-delay compensation method based on time-delay prediction and improved implicit generalized predictive control (GPC. The least squares support vector machine is used to predict the future time delay of network. The parameters of the least squares support vector machine time-delay prediction model are difficult to determine, and the genetic algorithm is used for least squares support vector machine optimal prediction parameter optimization. Then, an improved implicit generalized predictive control method is adopted to compensate for the time delay. The simulation results show that the method in this paper has high prediction accuracy and a good compensation effect for the random time delay of the networked control system, has a small amount of on-line calculation and that the output response and control stability of the system are improved.

  12. Monthly errors

    Data.gov (United States)

    U.S. Environmental Protection Agency — The 2006 monthly average statistical metrics for 2m Q (g kg-1) domain-wide for the base and MODIS WRF simulations against MADIS observations. This dataset is...

  13. A regional GIS-based model for reconstructing natural monthly streamflow series at ungauged sites

    Science.gov (United States)

    Pumo, Dario; Lo Conti, Francesco; Viola, Francesco; Noto, Leonardo V.

    2016-04-01

    Several hydrologic applications require reliable estimates of monthly runoff in river basins to face the widespread lack of data, both in time and in space. The main aim of this work is to propose a regional model for the estimation of monthly natural runoff series at ungauged sites, analyzing its applicability, reliability and limitations. A GIS (Geographic Information System) based model is here developed and applied to the entire region of Sicily (Italy). The core of this tool is a regional model for the estimation of monthly natural runoff series, based on a simple modelling structure, consisting of a regression based rainfall-runoff model with only four parameters. The monthly runoff is obtained as a function of precipitation and mean temperature at the same month and runoff at the previous month. For a given basin, the four model parameters are assessed by specific regional equations as a function of some easily measurable geomorphic and climate basins' descriptors. The model is calibrated by a "two-step" procedure applied to a number of gauged basins over the region. The first step is aimed at the identification of a set of parameters optimizing model performances at the level of single basin. Such "optimal" parameters sets, derived for each calibration basin, are successively used inside a regional regression analysis, performed at the second step, by which the regional equations for model parameters assessment are defined and calibrated. All the gauged watersheds across the Sicily have been analyzed, selecting 53 basins for model calibration and using other 6 basins exclusively for validation purposes. Model performances, quantitatively evaluated considering different statistical indexes, demonstrate a relevant model ability in capturing the observed hydrological response at both the monthly level and higher time scales (seasonal and annual). One of the key features related to the proposed methodology is its easy transferability to other arid and semiarid

  14. Climate change and compensation

    DEFF Research Database (Denmark)

    Jensen, Karsten Klint; Flanagan, Tine Bech

    2013-01-01

    This paper presents a case for compensation of actual harm from climate change in the poorest countries. First, it is shown that climate change threatens to reverse the fight to eradicate poverty. Secondly, it is shown how the problems raised in the literature for compensation to some extent...... are based on misconceptions and do not apply to compensation of present actual harm. Finally, two arguments are presented to the effect that, in so far as developed countries accept a major commitment to mitigate climate change, they should also accept a commitment to address or compensate actual harm from...... climate change. The first argument appeals to the principle that if it is an injustice to cause risk of incurring harm in the future, then it is also an injustice to cause a similar harm now. The second argument appeals to the principle that if there is moral reason to reduce the risk of specific harms...

  15. 14 CFR 158.53 - Collection compensation.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Collection compensation. 158.53 Section 158... Collection compensation. (a) As compensation for collecting, handling, and remitting the PFC revenue, the... a new compensation level based on an analysis of the data provided under paragraph (c)(1) of...

  16. Compensation models in chlorine doped CdTe based on positron annihilation and photoluminescence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Stadler, W.; Hofman, D.M.; Meyer, B.K. [Technische Universitaet Muenchen, Garching (Germany); Krause-Rehberg, R.; Polity, A.; Abgarjan, Th. [Martin-Luther Universitaet Halle-Wittenberg, FB Physik, Halle (Germany); Salk, M.; Benz, K.W. [Kristallographisches Institut, Universitaet Freiburg, Freiburg (Germany); Azoulay, M. [Soreq, Nuclear Research Centre, Yavne (Israel)

    1995-12-31

    In this investigation positron annihilation, photoluminescence and electron paramagnetic resonance techniques are employed to gain insight in the compensation of CdTe doped with the halogen Cl. We will demonstrate that the high resistivity of CdTe:Cl cannot be explain by the interaction between the shallow effective mass type donor Cl on Te site and the doping induced shallow acceptor complex, a Cd vacancy paired off with a nearest-neighbour Cl atom (A centre). From electron paramagnetic resonance investigations we conclude that the mid gap trap, often detected by electrical methods in CdTe, is not the isolated Cd vacancy. (author). 9 refs, 2 figs, 1 tab.

  17. Questioning Compensation

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Transparent management and open information needed for the fund set up to compensate victims of the 2008 Sanlu milk scandal Almost three years after the Sanlu milk scandal that caused thousands of infants in China to develop urinary disease after drinking melamine

  18. A Magnetic Disturbance Compensation Method Based on Magnetic Dipole Magnetic Field Distributing Theory

    Institute of Scientific and Technical Information of China (English)

    YANG Yun-tao; SHI Zhi-yong; L(U) Jian-gang; GUAN Zhen-zhen

    2009-01-01

    The interference of carrier magnetic field to geomagnetic field has been a difficult problem for a long time, which influences on the deviation of navigation compass and the error of geomagnetic measurement. To increase the geomagnetic measuring accuracy required for the geomagnetic matching localization, the strategy to eliminate the effect of connatural and induced magnetic fields of carrier on the geomagnetic measuring accuracy is investigated. The magnetic-dipoles magnetic field distributing theory is used to deduce the magnetic composition in the position of the sensor installed on the carrier. A geomagnetic measurement model is established by using the measuring data with the ideal sensor. Considering the magnetic disturbance of carrier and the error of sensor, a geomagnetic measuring compensation model is built. This model can be used to compensate the errors of carrier magnetic field and magnetic sensor in any case and its parameters have clear or specific physical meaning. The experimented results show that the model has higher geomagnetic measuring accuracy than that of others.

  19. A High Efficiency Charging Strategy for a Supercapacitor Using a Wireless Power Transfer System Based on Inductor/Capacitor/Capacitor (LCC Compensation Topology

    Directory of Open Access Journals (Sweden)

    Yuyu Geng

    2017-01-01

    Full Text Available In the application of rail transit vehicles, when using typical wireless power transfer (WPT systems with series–series (SS compensation supply power for supercapacitors, the output current is in an approximately inverse relationship with the duty cycle in a wide range. This renders the typical buck circuit control inappropriate. In order to help resolve the above issues, this paper designs inductor/capacitor/capacitor (LCC compensation with new compensation parameters, which can achieve an adjustable quasi-constant voltage from the input of the inverter to the output of the rectifier. In addition, the two-port network method is used to analyze the resonant compensation circuit. The analysis shows that LCC compensation is more suitable for the WPT system using the supercapacitor as the energy storage device. In the case of LCC compensation topology combined with the charging characteristics of the supercapacitor, an efficient charging strategy is designed, namely first constant current charging, followed by constant power charging. Based on the analysis of LCC compensation, the system has an optimal load, by which the system works at the maximum efficiency point. Combined with the characteristics of the constant voltage output, the system can maintain high efficiency in the constant power stage by making constant output power the same as the optimal power point. Finally, the above design is verified through experiments.

  20. A current-based model of the static synchronous series compensator (SSSC) for Newton-Raphson power flow

    Energy Technology Data Exchange (ETDEWEB)

    Vinkovic, Anton; Mihalic, Rafael [Faculty of Electrical Engineering, University of Ljubljana, Trzaska 25, 1000 Ljubljana (Slovenia)

    2008-10-15

    In this paper, a new approach to modeling a static synchronous series compensator (SSSC) for power-flow calculations by applying the Newton-Raphson method is presented. This new approach differs from known methods in terms of the interpretation of the device's branch. It is considered on the basis of its current and is therefore denoted as a current-based model of an SSSC. This approach might in principle be applicable also for other FACTS devices (i.e., UPFC, IPFC, GUPFC). In the paper, the current-based model of an SSSC is presented as the models of this device have difficulties with convergence in power-flow calculations and there are very few references covering these topics. First, the basic features of an SSSC are presented, as it is the basis for the current-based model that is incorporated into the Newton-Raphson load-flow model. The results of the tests at the IEEE 57-bus system are discussed in detail and compared with the existing injection SSSC load-flow model [X.P. Zhang, Advanced modeling of the multicontrol functional static synchronous series compensator (SSSC) in Newton power flow, IEEE Trans. Power Syst. 18 (November (4)) 2003]. (author)

  1. Stability analysis and compensation of network-induced delays in communication-based power system control: A survey.

    Science.gov (United States)

    Liu, Shichao; Liu, Peter Xiaoping; Wang, Xiaoyu

    2017-01-01

    This survey is to summarize and compare existing and recently emerging approaches for the analysis and compensation of the effects of network-induced delays on the stability and performance of communication-based power control systems. Several important communication-based power control systems are briefly introduced. The deterministic and stochastic methodologies of analyzing the impacts of network-induced delays on the stability of the communication-based power control systems are summarized and compared. A variety of control approaches are reviewed and compared for mitigating the effects of network-induced delays, depending on several design requirements, such as model dependence and design difficulty. The summary and comparison of these control approaches in this survey provide researchers and utilities valuable guidance for designing advanced communication-based power control systems in the future.

  2. Static Var Compensator based on Fuzzy Logic Control for Damping Power System Oscillation

    Directory of Open Access Journals (Sweden)

    Prechanon Kumkratug

    2011-01-01

    Full Text Available Problem statement: The disturbance in power system is unavoidable situation. It causes in power system oscillation. Approach: This study applied the Static Var Compensator (SVC to damp power system oscillation. The fuzzy logic control is applied to determine the control strategy of SVC. The simulation results are tested on a Single Machine Infinite bus. The proposed method is equipped in sample system with disturbance. The generator rotor angle curve of the system without and with a SVC is plotted and compared. Results: It was found that the system without a SVC has high variation whereas that of the system with a SVC has much smaller variation. Conclusion: From the simulation results, the SVC can damp power system oscillation.

  3. Compensation-based Game for Spectrum Sharing in the Gaussian Interference Channel

    Directory of Open Access Journals (Sweden)

    Z. Jing

    2010-12-01

    Full Text Available This paper considers an optimization problem of sum-rate in the Gaussian frequency-selective channel. We construct a competitive game with an asymptotically optimal compensation to approximate the optimization problem of sum-rate. Once the game achieves the Nash equilibrium, all users in the game will operate at the optimal sum-rate boundary. The contributions of this paper are twofold. On the one hand, a distributed power allocation algorithm called iterative multiple waterlevels water-filling algorithm is proposed to efficiently achieve the Nash equilibrium of the game. On the other hand, we derive some sufficient conditions on the convergence of iterative multiple waterlevels water-filling algorithm in this paper. Through simulation, the proposed algorithm has a significant improvement of the performance over iterative water filling algorithm and achieves the close-to-optimal performance.

  4. Identification and compensation of the temperature influences in a miniature three-axial accelerometer based on the least squares method

    Science.gov (United States)

    Grigorie, Teodor Lucian; Corcau, Ileana Jenica; Tudosie, Alexandru Nicolae

    2017-06-01

    The paper presents a way to obtain an intelligent miniaturized three-axial accelerometric sensor, based on the on-line estimation and compensation of the sensor errors generated by the environmental temperature variation. Taking into account that this error's value is a strongly nonlinear complex function of the values of environmental temperature and of the acceleration exciting the sensor, its correction may not be done off-line and it requires the presence of an additional temperature sensor. The proposed identification methodology for the error model is based on the least square method which process off-line the numerical values obtained from the accelerometer experimental testing for different values of acceleration applied to its axes of sensitivity and for different values of operating temperature. A final analysis of the error level after the compensation highlights the best variant for the matrix in the error model. In the sections of the paper are shown the results of the experimental testing of the accelerometer on all the three sensitivity axes, the identification of the error models on each axis by using the least square method, and the validation of the obtained models with experimental values. For all of the three detection channels was obtained a reduction by almost two orders of magnitude of the acceleration absolute maximum error due to environmental temperature variation.

  5. Research on Compensation Mechanism of Land Acquisition in Rural Areas Based on the Practice of Anhui Province

    Institute of Scientific and Technical Information of China (English)

    Huixian ZHOU; Zhongxiang YU

    2016-01-01

    With the continuous development of Chinese economy and rapid progress it has made,land demand for urban construction becomes larger and larger. Rural urbanization has a great relation to common prosperity and plays a key role in realizing the 21 st century great dream of Chinese people of all ethnic groups. Because of the complicated situation of land acquisition and compensation mechanism,we will conduct a systematic analysis on the compensation mechanism of land acquisition in Anhui Province and put forward the compensation methods to perfect the compensation mechanism according to the present compensation mechanism and the existing shortages of land acquisition in Anhui Province.

  6. Amount and Timing of Group-Based Childcare from Birth and Cognitive Development at 51 Months: A UK Study

    Science.gov (United States)

    Barnes, Jacqueline; Melhuish, Edward C.

    2017-01-01

    This study investigated whether the amount and timing of group-based childcare between birth and 51 months were predictive of cognitive development at 51 months, taking into account other non-parental childcare, demographic characteristics, cognitive development at 18 months, sensitive parenting and a stimulating home environment. Children's…

  7. Research on monthly flow uncertain reasoning model based on cloud theory

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In view of the mid and long term runoff forecasting containing many uncertain factors,this paper constructs a uncertain reasoning model (UR) based on the cloud theory to solve the problem of uncertain reasoning.Firstly,in the proposed model,a classification method,i.e.,attribute oriented induction maximum variance (MaxVar),is used to divide the runoff series into different intervals,which are softened and described by the cloud membership with expected value (Ex),entropy (En) and hyper-entropy (He),then an uncertain reasoning rule set is constructed by means of the runoff value generalization and applied to monthly flow for uncertain prediction.Next,a new modification formula is used to calculate He in runoff forecasting,and a confident level probability prediction interval is obtained by statistical method.Finally,this paper takes the monthly flow of Manwan station in China as an example and uses UR model,LSSVM model,and ARMA model to calculate the monthly flow,respectively.The results show that the UR model has the highest prediction accuracy compared to other models,and that it not only provides random output but also supports probability interval prediction.

  8. Application of a value-based equivalency method to assess environmental damage compensation under the European Environmental Liability Directive.

    Science.gov (United States)

    Martin-Ortega, Julia; Brouwer, Roy; Aiking, Harry

    2011-06-01

    The Environmental Liability Directive (ELD) establishes a framework of liability based on the 'polluter-pays' principle to prevent and remedy environmental damage. The ELD requires the testing of appropriate equivalency methods to assess the scale of compensatory measures needed to offset damage. The aim of this paper is to contribute to fill the existing knowledge gap on the application of the value equivalency approach for damage compensation in this context. We analyze the toxic spill damaging the Doñana National Park (Spain) in 1998. The welfare losses associated with the resource damage are estimated using non-market valuation and compared to the value of the compensatory measures taken after the accident. Our results show that the in-kind compensation may have been insufficient to offset the welfare losses. We conclude that a more comprehensive knowledge of the human welfare effects caused by environmental damage is of substantial importance to determine compensatory remediation, as insufficient information in this respect can lead to erroneous decisions causing loss to society. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. Heading Estimation with Real-time Compensation Based on Kalman Filter Algorithm for an Indoor Positioning System

    Directory of Open Access Journals (Sweden)

    Xin Li

    2016-06-01

    Full Text Available The problem of heading drift error using only low cost Micro-Electro-Mechanical (MEMS Inertial-Measurement-Unit (IMU has not been well solved. In this paper, a heading estimation method with real-time compensation based on Kalman filter has been proposed, abbreviated as KHD. For the KHD method, a unified heading error model is established for various predictable errors in magnetic compass for pedestrian navigation, and an effective method for solving the model parameters is proposed in the indoor environment with regular structure. In addition, error model parameters are solved by Kalman filtering algorithm with building geometry information in order to achieve real-time heading compensation. The experimental results show that the KHD method can not only effectively correct the original heading information, but also effectively inhibit the accumulation effect of positioning errors. The performance observed in a field experiment performed on the fourth floor of the School of Environmental Science and Spatial Informatics (SESSI building on the China University of Mining and Technology (CUMT campus confirms that apply KHD method to PDR(Pedestrian Dead Reckoning algorithm can reliably achieve meter-level positioning using a low cost MEMS IMU only.

  10. A Preamble-Based Frequency Offset Compensation Scheme in Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing Systems

    Directory of Open Access Journals (Sweden)

    Elnaz Ershadi

    2010-01-01

    Full Text Available Problem statement: Combining the properties of Multiple Input Multiple Output (MIMO systems with those of Orthogonal Frequency Division Multiplexing (OFDM, MIMO-OFDM was considered to be a promising technique in the future of wireless communications. However, its sensitivity to frequency offsets which results in Inter-Carrier Interferences (ICIs makes it necessary to use an exact frequency offset estimation method for data recovery in the MIMO-OFDM receiver. Approach: In this study, a new preamble-based frequency offset compensation method was introduced in frequency domain. In each block, two preambles are used to initially obtain the channel coefficients through LS channel estimation method. A polynomial curve fitting algorithm was then applied so that the frequency offsets experienced by every single data subcarrier are separately determined. Finally, to improve the compensating process, an iterative algorithm was applied. Results: Simulation results clearly showed that our proposed method was accurate in multipath fading channels and precisely recovered the transmitted data symbols. The BER performance of the iterative algorithm is within an acceptable distance of that in the ideal channel. Conclusion: In comparison with the conventional methods, our proposed scheme was less complex and showed better performance in lower SNRs. For further research, it can be investigated and improved while considering correlated antennas and spatial multiplexing.

  11. A Novel Systematic Error Compensation Algorithm Based on Least Squares Support Vector Regression for Star Sensor Image Centroid Estimation

    Directory of Open Access Journals (Sweden)

    Jingyan Song

    2011-07-01

    Full Text Available The star centroid estimation is the most important operation, which directly affects the precision of attitude determination for star sensors. This paper presents a theoretical study of the systematic error introduced by the star centroid estimation algorithm. The systematic error is analyzed through a frequency domain approach and numerical simulations. It is shown that the systematic error consists of the approximation error and truncation error which resulted from the discretization approximation and sampling window limitations, respectively. A criterion for choosing the size of the sampling window to reduce the truncation error is given in this paper. The systematic error can be evaluated as a function of the actual star centroid positions under different Gaussian widths of star intensity distribution. In order to eliminate the systematic error, a novel compensation algorithm based on the least squares support vector regression (LSSVR with Radial Basis Function (RBF kernel is proposed. Simulation results show that when the compensation algorithm is applied to the 5-pixel star sampling window, the accuracy of star centroid estimation is improved from 0.06 to 6 × 10−5 pixels.

  12. Elevation profile influence at key contractual performance parameters for LDS (Leak Detection Systems) based on compensated volume balance

    Energy Technology Data Exchange (ETDEWEB)

    Liebenberg, Lieb [TRANSNET Pipeline, Durban (South Africa); Bueno, David; Passos, Rafaela [KANOPUS Consulting, Rio de Janeiro, RJ (Brazil)

    2009-07-01

    This paper describes and discusses procedures and correlations to estimate performance parameters for Leak Detection Systems based on Compensation Volume Balance, at the portions not usually covered by international standards (like, API RP 1130). These parameters include: minimum acceptable leakage to be detected, under steady state conditions, based on flow measurement uncertainty, observed for both pipeline head and tail; an actual flow rate uncertainty against the one informed by the flow meter manufacturer documentation; the reference flow rate for steady state conditions; and the sensitivity one may expect for the system against a given probability of false alarms (i.e., the ways to correlate reliability, the main performance parameter as per API RP 1130 and sensitivity, the second one). A question usually not considered is: how the elevation profile may affect some of these parameters. That is the second main objective addressed herein, with actual examples employed in a South African multi product pipeline. (author)

  13. Ion beam figuring of high-slope surfaces based on figure error compensation algorithm.

    Science.gov (United States)

    Dai, Yifan; Liao, Wenlin; Zhou, Lin; Chen, Shanyong; Xie, Xuhui

    2010-12-01

    In a deterministic figuring process, it is critical to guarantee high stability of the removal function as well as the accuracy of the dwell time solution, which directly influence the convergence of the figuring process. Hence, when figuring steep optics, the ion beam is required to keep a perpendicular incidence, and a five-axis figuring machine is typically utilized. In this paper, however, a method for high-precision figuring of high-slope optics is proposed with a linear three-axis machine, allowing for inclined beam incidence. First, the changing rule of the removal function and the normal removal rate with the incidence angle is analyzed according to the removal characteristics of ion beam figuring (IBF). Then, we propose to reduce the influence of varying removal function and projection distortion on the dwell time solution by means of figure error compensation. Consequently, the incident ion beam is allowed to keep parallel to the optical axis. Simulations and experiments are given to verify the removal analysis. Finally, a figuring experiment is conducted on a linear three-axis IBF machine, which proves the validity of the method for high-slope surfaces. It takes two iterations and about 9 min to successfully figure a fused silica sample, whose aperture is 21.3 mm and radius of curvature is 16 mm. The root-mean-square figure error of the convex surface is reduced from 13.13 to 5.86 nm.

  14. Robust Sliding Mode Control Based on GA Optimization and CMAC Compensation for Lower Limb Exoskeleton.

    Science.gov (United States)

    Long, Yi; Du, Zhi-Jiang; Wang, Wei-Dong; Dong, Wei

    2016-01-01

    A lower limb assistive exoskeleton is designed to help operators walk or carry payloads. The exoskeleton is required to shadow human motion intent accurately and compliantly to prevent incoordination. If the user's intention is estimated accurately, a precise position control strategy will improve collaboration between the user and the exoskeleton. In this paper, a hybrid position control scheme, combining sliding mode control (SMC) with a cerebellar model articulation controller (CMAC) neural network, is proposed to control the exoskeleton to react appropriately to human motion intent. A genetic algorithm (GA) is utilized to determine the optimal sliding surface and the sliding control law to improve performance of SMC. The proposed control strategy (SMC_GA_CMAC) is compared with three other types of approaches, that is, conventional SMC without optimization, optimal SMC with GA (SMC_GA), and SMC with CMAC compensation (SMC_CMAC), all of which are employed to track the desired joint angular position which is deduced from Clinical Gait Analysis (CGA) data. Position tracking performance is investigated with cosimulation using ADAMS and MATLAB/SIMULINK in two cases, of which the first case is without disturbances while the second case is with a bounded disturbance. The cosimulation results show the effectiveness of the proposed control strategy which can be employed in similar exoskeleton systems.

  15. [An investigation of temperature compensation of HCL gas online monitoring based on TDLAS method].

    Science.gov (United States)

    Shu, Xiao-Wen; Zhang, Yu-Jun; Kan, Rui-Feng; Cui, Yi-Ben; He, Ying; Zhang, Shuai; Geng, Hui; Liu, Wen-Qing

    2010-05-01

    HCL, with the character of strong erosion and toxicity, is a kind of chemical material of vital importance. So measuring the HCL in-situ can not only optimize its production process, but also be necessary to reduce the environment pollution. TDLAS (tunable diode laser absorption spectroscopy) technology, and owning the advantage of the tunability and narrow line width of the diode laser, this method can relatively easily select the absorption line of the detected gas without the interference from other gas, thus making the rapid and accurate HCL measurement possible. In the present paper, the HCL measurement system and the implemented experiment are introduced. The impact of the temperature on the measurement as well as the temperature compensation method is emphasized. The final experimental results validated the rationality of the empirical equation and therefore the improvement of the accuracy and feasibility of the TDLAS technology. The system, whose detection limitation reaches 2 ppm, can satisfy the needs of industrial in-sit measurement.

  16. Temperature-compensated force/pressure sensor based on multi-walled carbon nanotube epoxy composites.

    Science.gov (United States)

    Dinh, Nghia Trong; Kanoun, Olfa

    2015-05-12

    In this study, we propose a multi-walled carbon nanotube epoxy composite sensor for force and pressure sensing in the range of 50 N-2 kN. A manufacturing procedure, including material preparation and deposition techniques, is proposed. The electrode dimensions and the layer thickness were optimized by the finite element method. Temperature compensation is realized by four nanocomposites elements, where only two elements are exposed to the measurand. In order to investigate the influence of the filler contents, samples with different compositions were prepared and investigated. Additionally, the specimens are characterized by cyclical and stepped force/pressure loads or at defined temperatures. The results show that the choice of the filler content should meet a compromise between sensitivity, temperature influence and noise behavior. At constant temperature, a force of at least 50N can be resolved. The measurement error due to the temperature influence is 150N in a temperature range of -20°C-50°C.

  17. Roll Eccentricity Compensation Based on Anti-Alias-sing Wavelet Analysis Method

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhi-ming; LUO Fei; XU Yu-ge; YU Wei

    2009-01-01

    Roll eccentricity is an important factor causing thickness variations during hot strip rolling and might define the limit of strip thickness control accuracy. An improved multi-resolution wavelet transform algorithm was proposed to compensate for the roll eccentricity. The wavelet transform method had good localization characteristics in both the time and frequency domains for signal analysis; however, the wavelet method had a frequency-aliasing problem owing to the less than ideal cut-off frequency characteristics of wavelets. This made its component reconstruction of an inaccurate signal. To eliminate inherent frequency aliases in the wavelet transform, fast Fourier transform (FFT) and inverse fast Fourier transform (IFFT) were combined with the Mallat algorithm. This synthesis was described in detail. Then, the roll eccentricity component was extracted from rolling force signal. An automatic gauge control (AGC) system added with a multi-resolution wavelet analyzer was designed. Experimental results showed that the anti-aliasing method could greatly restrain the inverse effect of eccentricity and the thickness control accuracy was im-proved from ±40 μm to ±15 μm.

  18. A Probe into the Reform of Land Requisition Compensation System: Based on the Survey of Rural Areas in Anhui Province

    Institute of Scientific and Technical Information of China (English)

    Liuzhong; CHEN; Zhongxiang; YU; Jiali; WANG

    2015-01-01

    Using stakeholder survey,documentation and policy analysis,through the survey of stakeholders,this paper aims to explore the problems in the collectively owned land requisition compensation system and their causes,and put forth the reform ideas and measures to provide a reference for the development of new urbanization. The results show that there are some problems in the current land requisition compensation system,such as improper land requisition compensation standard and calculation method,low compensation standard,unsound social security system,irrational compensation and placement methods and low satisfaction of farmers whose land is requisitioned. Therefore,it is necessary to accelerate the reform of land requisition compensation system and smooth progress of new urbanization construction in accordance with the requirements of 3rd Plenum of the 18 th Communist Party of China(CPC).

  19. Surface EMG decomposition based on K-means clustering and convolution kernel compensation.

    Science.gov (United States)

    Ning, Yong; Zhu, Xiangjun; Zhu, Shanan; Zhang, Yingchun

    2015-03-01

    A new approach has been developed by combining the K-mean clustering (KMC) method and a modified convolution kernel compensation (CKC) method for multichannel surface electromyogram (EMG) decomposition. The KMC method was first utilized to cluster vectors of observations at different time instants and then estimate the initial innervation pulse train (IPT). The CKC method, modified with a novel multistep iterative process, was conducted to update the estimated IPT. The performance of the proposed K-means clustering-Modified CKC (KmCKC) approach was evaluated by reconstructing IPTs from both simulated and experimental surface EMG signals. The KmCKC approach successfully reconstructed all 10 IPTs from the simulated surface EMG signals with true positive rates (TPR) of over 90% with a low signal-to-noise ratio (SNR) of -10 dB. More than 10 motor units were also successfully extracted from the 64-channel experimental surface EMG signals of the first dorsal interosseous (FDI) muscles when a contraction force was held at 8 N by using the KmCKC approach. A "two-source" test was further conducted with 64-channel surface EMG signals. The high percentage of common MUs and common pulses (over 92% at all force levels) between the IPTs reconstructed from the two independent groups of surface EMG signals demonstrates the reliability and capability of the proposed KmCKC approach in multichannel surface EMG decomposition. Results from both simulated and experimental data are consistent and confirm that the proposed KmCKC approach can successfully reconstruct IPTs with high accuracy at different levels of contraction.

  20. A Comparison of Different Regression Algorithms for Downscaling Monthly Satellite-Based Precipitation over North China

    Directory of Open Access Journals (Sweden)

    Wenlong Jing

    2016-10-01

    Full Text Available Environmental monitoring of Earth from space has provided invaluable information for understanding land–atmosphere water and energy exchanges. However, the use of satellite-based precipitation observations in hydrologic and environmental applications is often limited by their coarse spatial resolutions. In this study, we propose a downscaling approach based on precipitation–land surface characteristics. Daytime land surface temperature, nighttime land surface temperature, and day–night land surface temperature differences were introduced as variables in addition to the Normalized Difference Vegetation Index (NDVI, the Digital Elevation Model (DEM, and geolocation (longitude, latitude. Four machine learning regression algorithms, the classification and regression tree (CART, the k-nearest neighbors (k-NN, the support vector machine (SVM, and random forests (RF, were implemented to downscale monthly TRMM 3B43 V7 precipitation data from 25 km to 1 km over North China for the purpose of comparison of algorithm performance. The downscaled results were validated based on observations from meteorological stations and were also compared to a previous downscaling algorithm. According to the validation results, the RF-based model produced the results with the highest accuracy. It was followed by SVM, CART, and k-NN, but the accuracy of the downscaled results using SVM relied greatly on residual correction. The downscaled results were well correlated with the observations during the year, but the accuracies were relatively lower in July to September. Downscaling errors increase as monthly total precipitation increases, but the RF model was less affected by this proportional effect between errors and observation compared with the other algorithms. The variable importances of the land surface temperature (LST feature variables were higher than those of NDVI, which indicates the significance of considering the precipitation–land surface temperature

  1. Alternative Teacher Compensation: A Primer

    Science.gov (United States)

    Koppich, Julia E.; Rigby, Jessica

    2009-01-01

    This policy primer is designed to provide base-line information about new forms of teacher pay that are emerging around the country, to support the local conversations and negotiations that will lead to the development of innovative compensation systems. It identifies reasons why teacher compensation is high on local, state, and federal policy…

  2. Complete compensation of pulse broadening in an amplifier-based slow light system using a nonlinear regeneration element.

    Science.gov (United States)

    Chin, Sanghooon; Gonzalez-Herraez, Miguel; Thévenaz, Luc

    2009-11-23

    We experimentally demonstrate complete compensation of pulse broadening in an amplifier-based slow light system. The configuration of the delay line basically consists of two stages: a conventional Brillouin slow light system and a nonlinear regeneration element. Signal pulses experienced both time delay and temporal broadening through the Brillouin delay line and then the delayed pulses were delivered into a nonlinear optical loop mirror. Due to the nonlinear response of the transmission of the fiber loop, the inevitably broadened pulses were moderately compressed in the output of the loop, without loss in the capacity to delay the pulses. The overall result is that, for the maximum delay, the width of the pulse could be kept below the input width while the time delays introduced by the slow light element were preserved. Using this delay line, a signal pulse with duration of 27 ns at full width at half maximum was delayed up to 1.3-bits without suffering from signal distortion.

  3. Research on the filtering characteristic of single phase series hybrid active power filter based on fundamental magnetic flux compensation

    Science.gov (United States)

    Tian, Jun; Chen, Qiaofu; Zhang, Yuqi

    2012-12-01

    In this article, the PWM inverter works as a controlled fundamental current source in the single phase series hybrid active power filter (APF) based on fundamental magnetic flux compensation (FMFC). The series transformer can exhibit the self-impedance of primary winding to harmonic current, which forces harmonic current to flow into passive power filter. With the influence of harmonic current, the voltage of primary winding of transformer is a harmonic voltage, which makes the inverter output currents have a certain harmonic component, and it degrades the filtering characteristics. On the basis of PWM inverter, the mathematical model of series hybrid APF is established, and the filtering characteristics of single phase APF are analysed in detail. Three methods are gained to improve filtering characteristics: reasonably designing the inverter output filter inductance, increasing series transformer ratio and adopting voltage feed-forward control. Experimental results show that the proposed APF has greater validity.

  4. Adapting industry-style business model to academia in a system of Performance-based Incentive Compensation.

    Science.gov (United States)

    Reece, E Albert; Nugent, Olan; Wheeler, Richard P; Smith, Charles W; Hough, Aubrey J; Winter, Charles

    2008-01-01

    Performance-Based Incentive Compensation (PBIC) plans currently prevail throughout industry and have repeatedly demonstrated effectiveness as powerful motivational tools for attracting and retaining top talent, enhancing key indicators, increasing employee productivity, and, ultimately, enhancing mission-based parameters. The University of Arkansas for Medical Sciences (UAMS) College of Medicine introduced its PBIC plan to further the transition of the college to a high-performing academic and clinical enterprise. A forward-thinking compensation plan was progressively implemented during a three-year period. After the introduction of an aggressive five-year vision plan in 2002, the college introduced a PBIC plan designed to ensure the retention and recruitment of high-quality faculty through the use of uncapped salaries that reflect each faculty member's clinical, research, and education duties. The PBIC plan was introduced with broad, schoolwide principles adaptable to each department and purposely flexible to allow for tailor-made algorithms to fit the specific approaches required by individual departments. As of July 2006, the college had begun to reap a variety of short-term benefits from Phase I of its PBIC program, including increases in revenue and faculty salaries, and increased faculty morale and satisfaction.Successful implementation of a PBIC plan depends on a host of factors, including the development of a process for evaluating performance that is considered fair and reliable to the entire faculty. The college has become more efficient and effective by adopting such a program, which has helped it to increase overall productivity. The PBIC program continues to challenge our faculty members to attain their highest potential while rewarding them accordingly.

  5. Full dates (day, month, year) should be used in population-based cancer survival studies.

    Science.gov (United States)

    Woods, Laura M; Rachet, Bernard; Ellis, Libby; Coleman, Michel P

    2012-10-01

    Accurate survival estimates are essential for monitoring cancer survival trends, for health care planning and for resource allocation. To obtain precise estimates of survival, full dates (day, month and year) rather than partial dates (month and year) are required. In some jurisdictions, however, cancer registries are constrained from providing full dates on the grounds of confidentiality. The bias resulting from the use of partial dates in the estimation and comparison of survival makes it impossible to determine precisely the differences in the risk of death from cancer between population groups or in successive calendar periods. Important operational arguments also exist against the use of incomplete dates for survival analysis, including increased workload for cancer registry staff and the introduction of avoidable complexity for quality control of survival data. Cancer survival is one of the most widely known outputs produced by population-based cancer registries, and it is a crucial metric for the comparative effectiveness of health services. The bodies that set data access guidelines must take a more balanced view of the risks and benefits of using full dates for the estimation of cancer survival.

  6. Effects of a 12-Month Pedometer-Based Walking Intervention in Women of Low Socioeconomic Status

    Science.gov (United States)

    Hornbuckle, Lyndsey M.; Kingsley, J. Derek; Kushnick, Michael R.; Moffatt, Robert J.; Haymes, Emily M.; Miles, Rebecca; Toole, Tonya; Panton, Lynn B.

    2016-01-01

    This study examined the effects of a 12-month walking intervention in overweight/obese, low socioeconomic women. Forty-six women (48.2 ± 8.0 years) entered the study. Outcomes included weight, waist and hip circumferences, body mass index (BMI), blood pressure, glycosylated hemoglobin, blood lipids, fibrinogen, and high-sensitivity C-reactive protein (hsCRP). Both intention-to-treat analyses in all participants and group analyses in study completers only (3K group = increased steps/day by ≥3,000; No Δ group = did not increase steps/day by ≥3,000) were conducted. Group × time ANOVA was used. In study completers, 3K significantly increased steps/day (6,903 ± 3,328 to 12,323 ± 5,736) compared to No Δ (4,926 ± 3,374 to 5,174 ± 3,095) from baseline to 12 months. There was a significant time effect for weight (P = 0.030), BMI (P = 0.029), and hsCRP (P = 0.044). Low socioeconomic women who adhere to a long-term, pedometer-based walking intervention significantly increased steps/day and may improve body weight, BMI, and hsCRP. This could help reduce health disparities in this population over time. PMID:27746679

  7. A temperature compensation procedure for performance improvement of mass-produced MEMS gyroscopes based on direct parameter measurement

    Science.gov (United States)

    Straube, Timothy Milton

    Micro Electro Mechanical Systems gyroscopes are an enabling technology for many rate sensing applications that require low cost, mass and volume, including the class of spacecraft known as nano- or pico-satellites. The weakness of these types of gyroscopes to date has been limited performance capabilities, especially over a varying temperature range. This thesis presents a methodology for correcting the gyroscope output signal for variations over temperature based on measurements of specific internal gyro parameters, namely, drive and sense axis resonant frequency, and off-axis electrostatic forcing function. The thesis presents the development of the full analytical equations of motion for a translating type MEMS gyro. The equations are simplified, numerically validated, and decomposed for gyro scale factor and bias expressions. Employing gyroscope parameters obtained from open literature sources as a function of temperature, a reference model of gyro scale factor and bias voltage as a function of temperature is developed. The research also includes the empirical testing of two types of gyro, and ten total individual devices, including eight ADXRS150 automotive grade gyroscopes from Analog Devices. Device outputs at temperatures from -35°C to +75°C and across a range of rotation rate were measured and processed to calculate individual gyro scale factor and bias. Data from all gyros were analyzed using a principal component methodology to extract the dominant structures in the gyro behavior. The final correction model is individualized for each gyro using ambient scale factor and bias data from that gyro. This model is used to compensate the individual raw gyro output taken during testing. Compositing the compensated output from all gyro provides a final rate estimate, which can be compared against the known testing inputs. The results demonstrate considerable improvement over manufacturer-provided scale factor and bias correction values. With the linkage between

  8. Changes in Neurocognitive Functioning After 6 Months of Mentalization-Based Treatment for Borderline Personality Disorder

    DEFF Research Database (Denmark)

    Thomsen, Marianne Skovgaard; Ruocco, Anthony C; Uliaszek, Amanda A

    2016-01-01

    Patients with borderline personality disorder (BPD) have deficits in neurocognitive function that could affect their ability to engage in psychotherapy and may be ameliorated by improvements in symptom severity. In the current study, 18 patients with BPD completed neurocognitive tests prior...... working memory. After 6 months of treatment, patients showed significantly greater increases in sustained attention and perceptual reasoning than controls, with initial deficits in sustained attention among patients resolving after treatment. Improved emotion regulation over the follow-up period...... was associated with increased auditory-verbal working memory capacity, whereas interpersonal functioning improved in parallel with perceptual reasoning. These findings suggest that changes in neurocognitive functioning may track improvements in clinical symptoms in mentalization-based treatment for BPD....

  9. Is Trust for Sale? The Effectiveness of Financial Compensation for Repairing Competence- versus Integrity-Based Trust Violations.

    Science.gov (United States)

    Haesevoets, Tessa; Reinders Folmer, Chris; Van Hiel, Alain

    2015-01-01

    Despite the popularity of financial compensation as a means for addressing trust violations, the question whether (more) money can indeed buy trust back remains largely unexplored. In the present research, we focus on the role of violation type and compensation size. The results of a scenario study and a laboratory experiment show that financial compensation can effectively promote the restoration of trust for transgressions that indicate a lack of competence. Conversely, for transgressions which signal a lack of integrity, financial compensation is not an effective tool to repair trust. Moreover, our findings indicate that for both violation types, overcompensation has no positive effects on top of the impact of equal compensation. These findings therefore show that when it comes to trust, money cannot buy everything.

  10. Global Monthly CO2 Flux Inversion Based on Results of Terrestrial Ecosystem Modeling

    Science.gov (United States)

    Deng, F.; Chen, J.; Peters, W.; Krol, M.

    2008-12-01

    Most of our understanding of the sources and sinks of atmospheric CO2 has come from inverse studies of atmospheric CO2 concentration measurements. However, the number of currently available observation stations and our ability to simulate the diurnal planetary boundary layer evolution over continental regions essentially limit the number of regions that can be reliably inverted globally, especially over continental areas. In order to overcome these restrictions, a nested inverse modeling system was developed based on the Bayesian principle for estimating carbon fluxes of 30 regions in North America and 20 regions for the rest of the globe. Inverse modeling was conducted in monthly steps using CO2 concentration measurements of 5 years (2000 - 2005) with the following two models: (a) An atmospheric transport model (TM5) is used to generate the transport matrix where the diurnal variation n of atmospheric CO2 concentration is considered to enhance the use of the afternoon-hour average CO2 concentration measurements over the continental sites. (b) A process-based terrestrial ecosystem model (BEPS) is used to produce hourly step carbon fluxes, which could minimize the limitation due to our inability to solve the inverse problem in a high resolution, as the background of our inversion. We will present our recent results achieved through a combination of the bottom-up modeling with BEPS and the top-down modeling based on TM5 driven by offline meteorological fields generated by the European Centre for Medium Range Weather Forecast (ECMFW).

  11. Error Analysis and Compensation of Gyrocompass Alignment for SINS on Moving Base

    Directory of Open Access Journals (Sweden)

    Bo Xu

    2014-01-01

    Full Text Available An improved method of gyrocompass alignment for strap-down inertial navigation system (SINS on moving base assisted with Doppler velocity log (DVL is proposed in this paper. After analyzing the classical gyrocompass alignment principle on static base, implementation of compass alignment on moving base is given in detail. Furthermore, based on analysis of velocity error, latitude error, and acceleration error on moving base, two improvements are introduced to ensure alignment accuracy and speed: (1 the system parameters are redesigned to decrease the acceleration interference and (2 a data repeated calculation algorithm is used in order to shorten the prolonged alignment time caused by changes in parameters. Simulation and test results indicate that the improved method can realize the alignment on moving base quickly and effectively.

  12. Compensation of position errors in passivity based teleoperation over packet switched communication networks

    NARCIS (Netherlands)

    Secchi, C; Stramigioli, Stefano; Fantuzzi, C.

    Because of the use of scattering based communication channels, passivity based telemanipulation systems can be subject to a steady state position error between master and slave robots. In this paper, we consider the case in which the passive master and slave sides communicate through a packet

  13. Compensation of Wave-Induced Motion and Force Phenomena for Ship-Based High Performance Robotic and Human Amplifying Systems

    Energy Technology Data Exchange (ETDEWEB)

    Love, LJL

    2003-09-24

    Learning Controller has little impact due to the variable nature of the wave period. We then introduce a new approach to HAT control, Ship Motion Compensation for Force Control Systems (SMCFCS). This basic approach uses inclinometer and acceleration information from the base of the robot to compensate for ship motion disturbances. Results of the simulation study show over an order of magnitude decrease in the disturbance force reflected back to the operator and an order of magnitude increase in positioning accuracy and resolution.

  14. A Study of the School Principal Labor Market in Arkansas: Implications for Incentive-Based Compensation Policies to Improve Principal Quality

    Science.gov (United States)

    Holley, Marc Jacob

    2009-01-01

    Improving principal quality in Arkansas may be a partial solution to the public policy problem of low performing public schools. Just as policymakers in other states are beginning to explore incentive-based compensation policies to improve principal quality, education policymakers in Arkansas should look to these policies as a way to align goals…

  15. Dynamic Phase Compensation of wind turbines

    DEFF Research Database (Denmark)

    Soerensen, P.; Skaarup, J.; Iov, Florin

    2004-01-01

    This paper describes a dynamic phase compensation unit for a wind turbine with directly connected induction generators. The compensation unit is based on thyristor switched capacitors, where conventional wind turbine compensations use mechanical contactors to switch the capacitors. The unit modul...

  16. Enhanced control of DFIG wind turbine based on stator flux decay compensation

    DEFF Research Database (Denmark)

    Zhu, Rongwu; Deng, Fujin; Chen, Zhe;

    2016-01-01

    For the doubly-fed induction generator (DFIG)- based wind energy conversion system (WECS), the decaying flux and negative flux are the main reasons to cause the DFIG rotor overcurrent, during grid faults. The stator decaying flux characteristics versus the depth and instant of the stator voltage...... is significantly reduced during grid faults. The experimental results based on the 7.5 kW DFIG setup is carried to validate the correctness and feasibility of the proposed strategy. Dynamic voltage restorer (DVR) can be one of the applications. With the proposed strategy, the DVR only works in a half fundamental...... period and its output voltage amplitude is half of the stator voltage variation, during the grid voltage drop and recovery, respectively. As a consequence, the DVR can be rated for lower power saving cost. The simulation results based on Matlab/Simulink using a 2 MW DFIG and the experimental results...

  17. Monthly-averaged anthropogenic aerosol direct radiative forcing over the Mediterranean based on AERONET aerosol properties

    Directory of Open Access Journals (Sweden)

    A. Bergamo

    2008-12-01

    Full Text Available The all-sky direct radiative effect by anthropogenic aerosol (DREa is calculated in the solar (0.3–4 μm and infrared (4–200 μm spectral ranges for six Mediterranean sites. The sites are differently affected by pollution and together reflect typical aerosol impacts that are expected over land and coastal sites of the central Mediterranean basin. Central to the simulations are aerosol optical properties from AERONET sun-/sky-photometer statistics for the year 2003. A discussion on the variability of the overall (natural + anthropogenic aerosol properties with site location is provided. Supplementary data include MODIS satellite sensor based solar surface albedos, ISCCP products for high- mid- and low cloud cover and estimates for the anthropogenic aerosol fraction from global aerosol models. Since anthropogenic aerosol particles are considered to be smaller than 1 μm in size, mainly the solar radiation transfer is affected with impacts only during sun-light hours. At all sites the (daily average solar DREa is negative all year round at the top of the atmosphere (ToA. Hence, anthropogenic particles produce over coastal and land sites of the central Mediterranean a significant cooling effect. Monthly DREa values vary from site to site and are seasonally dependent as a consequence of the seasonal dependence of available sun-light and microphysical aerosol properties. At the ToA the monthly average DREa is −(4±1 W m−2 during spring-summer (SS, April–September and −(2±1 W m−2 during autumn-winter (AW, October–March at the polluted sites. In contrast, it varies between −(3±1 W m−2 and −(1±1 W m−2 on SS and AW, respectively at the less polluted site. Due to atmospheric absorption the DREa at the surface is larger than at the ToA. At the surface the monthly average DREa varies between the most and the least polluted

  18. 基于直流潮流的无功补偿自动配置方法%DC Power Flow Based Automatic Configuration of Reactive Power Compensators

    Institute of Scientific and Technical Information of China (English)

    王毅; 马世英; 王虹富; 董毅峰; 侯俊贤; 李晓斌

    2014-01-01

    提出了一种基于直流潮流的无功补偿自动配置方法。该方法针对已安排好的网架结构及参数、发电出力和负荷计算直流潮流,依据支路有功潮流分布估算节点理想无功补偿量;考虑并联电容电抗器的实际装设情况将无功补偿量转移到具有无功补偿能力的节点上;根据实际无功装置的单组容量和组数进行离散化,最终获得符合实际的无功补偿配置方案。该方法适用于方式安排中初始潮流方式的生成,为制定合理的运行方式提供帮助。基于实际电网的测试算例表明,该方法正确有效,简单实用,能够制定合理的初始无功补偿配置方案。%A DC power flow based automatic configuration of reactive power compensators is proposed. Based on the planned frame structure and parameters power grid, output of generating units and load the DC power flow is calculated, and according to the distribution of the active power flow in branches the amount of ideal reactive power compensation is estimated; considering actual installation of shunt capacitors and reactors the amount of reactive compensation is transferred to the nodes with the capability of reactive compensation;then the ideal compensation amount is according to the capacity of single-bank of capacitor and the number of banks the ideal compensation amount is discretized, and finally a configuration scheme of reactive power compensators is obtained. The proposed method is suitable for the formation of the initial power flow in the operation mode arrangement to offer the help for the drafting of reasonable operation modes. Results of the actual power grid based testing cases show that the proposed method is correct, effective, simple and convenient to use, and using this method a reasonable initial configuration scheme of reactive power compensators can be achieved.

  19. Origin and compensation of imaging artefacts in localization-based super-resolution microscopy.

    Science.gov (United States)

    Erdélyi, M; Sinkó, J; Kákonyi, R; Kelemen, A; Rees, E; Varga, D; Szabó, G

    2015-10-15

    Interpretation of high resolution images provided by localization-based microscopy techniques is a challenge due to imaging artefacts that can be categorized by their origin. They can be introduced by the optical system, by the studied sample or by the applied algorithms. Some artefacts can be eliminated via precise calibration procedures, others can be reduced only below a certain value. Images studied both theoretically and experimentally are qualified either by pattern specific metrics or by a more general metric based on fluorescence correlation spectroscopy.

  20. BPM Electronics based on Compensated Diode Detectors – Results from development Systems

    CERN Document Server

    Gasior, M; Steinhagen, RJ

    2012-01-01

    High resolution beam position monitor (BPM) electronics based on diode peak detectors is being developed for processing signals from button BPMs embedded into future LHC collimators. Its prototypes were measured in a laboratory as well as with beam signals from the collimator BPM installed on the SPS and with LHC BPMs. Results from these measurements are presented and discussed.

  1. MEMS Inertial Sensors-Based Multi-Loop Control Enhanced by Disturbance Observation and Compensation for Fast Steering Mirror System

    Directory of Open Access Journals (Sweden)

    Chao Deng

    2016-11-01

    Full Text Available In this paper, an approach to improve the disturbance suppression performance of a fast steering mirror (FSM tracking control system based on a charge-coupled device (CCD and micro-electro-mechanical system (MEMS inertial sensors is proposed. The disturbance observation and compensation (DOC control method is recommended to enhance the classical multi-loop feedback control (MFC for line-of-sight (LOS stabilization in the FSM system. MEMS accelerometers and gyroscopes have been used in the FSM system tentatively to implement MFC instead of fiber-optic gyroscopes (FOG because of its smaller, lighter, cheaper features and gradually improved performance. However, the stabilization performance of FSM is still suffering a large number of mechanical resonances and time delay induced by a low CCD sampling rate, which causes insufficient error attenuation when suffering uncertain disturbances. Thus, in order to make further improvements on the stabilization performance, a cascaded MFC enhanced by DOC method is proposed. The sensitivity of this method shows the significant improvement of the conventional MFC system. Simultaneously, the analysis of stabilization accuracy is also presented. A series of comparative experimental results demonstrate the disturbance suppression performance of the FSM control system based on the MEMS inertial sensors can be effectively improved by the proposed approach.

  2. Adaptive fuzzy tracking control for a constrained flexible air-breathing hypersonic vehicle based on actuator compensation

    Directory of Open Access Journals (Sweden)

    Peng Fei Wang

    2016-10-01

    Full Text Available The design of an adaptive fuzzy tracking control for a flexible air-breathing hypersonic vehicle with actuator constraints is discussed. Based on functional decomposition methodology, velocity and altitude controllers are designed. Fuzzy logic systems are applied to approximate the lumped uncertainty of each subsystem of air-breathing hypersonic vehicle model. Every controllers contain only one adaptive parameter that needs to be updated online with a minimal-learning-parameter scheme. The back-stepping design is not demanded by converting the altitude subsystem into the normal output-feedback formulation, which predigests the design of a controller. The special contribution is that novel auxiliary systems are developed to compensate both the tracking errors and desired control laws, based on which the explored controller can still provide effective tracking of velocity and altitude commands when the inputs are saturated. Finally, reference trajectory tracking simulation shows the effectiveness of the proposed method in its application to air-breathing hypersonic vehicle control.

  3. Data fusion for compensation of temperature variations in Lamb-wave based SHM systems

    Science.gov (United States)

    Dworakowski, Ziemowit; Ambrozinski, Lukasz; Stepinski, Tadeusz

    2015-03-01

    Temperature variations affect Lamb wave propagation and therefore in this way they can severely limit application of baseline signals in SHM systems. Various techniques are proposed in the paper to solve this problem. New method based on an interpretation of multiple signals acquired in distinct points of the structure is introduced and compared with other widely used approaches. Data fusion is used to merge a number of methods into one with a substantially increased efficiency.

  4. An approach of inertia compensation based on electromagnetic induction in brake test

    Directory of Open Access Journals (Sweden)

    Xiaowen Li

    2016-04-01

    Full Text Available This paper briefly introduced the operational principle of the brake test bench, and points out the shortcomings when controlling the current of brake test, which means the reference measuring data is instantaneous. Aimed at this deficiency, a current control model based on electromagnetic induction and DC voltage is proposed. On the principle of electromagnetic induction, continuous data and automatic processes are realized. It significantly minimized errors owing to instantaneous data, and maximized the accuracy of the brake test.

  5. Error compensation in computer generated hologram-based form testing of aspheres.

    Science.gov (United States)

    Stuerwald, Stephan

    2014-12-10

    Computer-generated holograms (CGHs) are used relatively often to test aspheric surfaces in the case of medium and high lot sizes. Until now differently modified measurement setups for optical form testing interferometry have been presented, like subaperture stitching interferometry and scanning interferometry. In contrast, for testing low to medium lot sizes in research and development, a variety of other tactile and nontactile measurement methods have been developed. In the case of CGH-based interferometric form testing, measurement deviations in the region of several tens of nanometers typically occur. Deviations arise especially due to a nonperfect alignment of the asphere relative to the testing wavefront. Therefore, the null test is user- and adjustment-dependent, which results in insufficient repeatability and reproducibility of the form errors. When adjusting a CGH, an operator usually performs a minimization of the spatial frequency of the fringe pattern. An adjustment to the ideal position, however, often cannot be performed with sufficient precision by the operator as the position of minimum spatial fringe density is often not unique, which also depends on the asphere. Thus, the scientific and technical objectives of this paper comprise the development of a simulation-based approach to explain and quantify typical experimental errors due to misalignment of the specimen toward a CGH in an optical form testing measurement system. A further step is the programming of an iterative method to realize a virtual optimized realignment of the system on the basis of Zernike polynomial decomposition, which should allow for the calculation of the measured form for an ideal alignment and thus a careful subtraction of a typical alignment-based form error. To validate the simulation-based findings, a series of systematic experiments is performed with a recently developed hexapod positioning system in order to allow an exact and reproducible positioning of the optical CGH-based

  6. Surgeon compensation and motivation.

    Science.gov (United States)

    Leitch, K K; Walker, P M

    2000-06-01

    Financial incentives are the only form of compensation that will motivate surgeons at an academic health sciences center to perform the tasks outlined in the hospital's mission statement. A questionnaire divided into 5 sections: demographics, compensation, time allocation, benefits and incentives, and motivational factors. The Department of Surgery, The Toronto Hospital, Toronto, Ontario. All academic surgeons (N=64) practicing at The Toronto Hospital in July 1997. Of the 64 eligible mailed surveys, there were responses for 59. Of these 59 surgeons, 48 (81%) receive compensation through a fee-for-service method. However, only 32 (54%) of the surgeons prefer the fee-for-service method, while 18 (31%) prefer salary and 9 (15%) prefer an alternative system. On average, these academic surgeons spend 44% of their time teaching or performing research, for which they receive 14% of their total income. Of the motivational factors assessed, financial bonuses are a positive motivational factor for all "surgeon tasks." In addition, task-specific motivational factors were established for research, teaching, and operating, including research facilities, mentorship and prestige, and interesting case types, respectively. Surgeons are not appropriately renumerated for time spent on academic activities, and many would prefer an alternative form of compensation to the fee-for-service method. Knowledge that surgeons are receptive to tasks supporting the hospital's mission statement leads us to conclude that appropriate motivation can shape the activity of academic surgeons. Financial rewards ranked the highest as a motivational factor for all surgeon tasks; however, task-specific motivational factors were identified. Overall, multiple factors, specifically targeted to the individual, will serve to motivate. Thus, compensation packages based on individual preferences and personal motivational factors will be the most successful.

  7. Assessment criteria for compensation of occupational bladder cancer.

    Science.gov (United States)

    Schops, Wolfgang; Jungmann, Olaf; Zumbe, Jurgen; Zellner, Michael; Hengstler, Jan G; Golka, Klaus

    2013-01-01

    In Germany, more than 100 bladder tumor cases are annually recognized as occupational disease and compensated, given that medical experts regard exposure to carcinogenic aromatic amines as a likely cause of cancer. The amount of compensation is initially based on the tumor staging and grading at the time of initial diagnosis ("basic MdE") (MdE--reduction of earning capacity) and is adapted after a recurrence-free period of 2 and 5 years, respectively. In the event of treatment or tumor-related secondary conditions, the monthly compensation increases based on the severity of the objectified functional disorder. In the following article, medical experts specializing in this field provide a complete list of all known disorders, including treatment-related loss of a kidney or erectile dysfunction. In addition, the weighting of medical criteria in the assessment and calculation of the compensation is analyzed in greater detail. Since the given criteria are based on comprehensible experiences of urologists with their patients, they also provide medical experts in other countries with valuable points of reference for the calculation of the compensation.

  8. Height Compensation Using Ground Inclination Estimation in Inertial Sensor-Based Pedestrian Navigation

    Directory of Open Access Journals (Sweden)

    Sang Kyeong Park

    2011-08-01

    Full Text Available In an inertial sensor-based pedestrian navigation system, the position is estimated by double integrating external acceleration. A new algorithm is proposed to reduce z axis position (height error. When a foot is on the ground, a foot angle is estimated using accelerometer output. Using a foot angle, the inclination angle of a road is estimated. Using this road inclination angle, height difference of one walking step is estimated and this estimation is used to reduce height error. Through walking experiments on roads with different inclination angles, the usefulness of the proposed algorithm is verified.

  9. Incomplete Sex Chromosome Dosage Compensation in the Indian Meal Moth, Plodia interpunctella, Based on De Novo Transcriptome Assembly

    Science.gov (United States)

    Harrison, Peter W.; Mank, Judith E.; Wedell, Nina

    2012-01-01

    Males and females experience differences in gene dose for loci in the nonrecombining region of heteromorphic sex chromosomes. If not compensated, this leads to expression imbalances, with the homogametic sex on average exhibiting greater expression due to the doubled gene dose. Many organisms with heteromorphic sex chromosomes display global dosage compensation mechanisms, which equalize gene expression levels between the sexes. However, birds and Schistosoma have been previously shown to lack chromosome-wide dosage compensation mechanisms, and the status in other female heterogametic taxa including Lepidoptera remains unresolved. To further our understanding of dosage compensation in female heterogametic taxa and to resolve its status in the lepidopterans, we assessed the Indian meal moth, Plodia interpunctella. As P. interpunctella lacks a complete reference genome, we conducted de novo transcriptome assembly combined with orthologous genomic location prediction from the related silkworm genome, Bombyx mori, to compare Z-linked and autosomal gene expression levels for each sex. We demonstrate that P. interpunctella lacks complete Z chromosome dosage compensation, female Z-linked genes having just over half the expression level of males and autosomal genes. This finding suggests that the Lepidoptera and possibly all female heterogametic taxa lack global dosage compensation, although more species will need to be sampled to confirm this assertion. PMID:23034217

  10. Dynamic Feedforward Control of a Diesel Engine Based on Optimal Transient Compensation Maps

    Directory of Open Access Journals (Sweden)

    Giorgio Mancini

    2014-08-01

    Full Text Available To satisfy the increasingly stringent emission regulations and a demand for an ever lower fuel consumption, diesel engines have become complex systems with many interacting actuators. As a consequence, these requirements are pushing control and calibration to their limits. The calibration procedure nowadays is still based mainly on engineering experience, which results in a highly iterative process to derive a complete engine calibration. Moreover, automatic tools are available only for stationary operation, to obtain control maps that are optimal with respect to some predefined objective function. Therefore, the exploitation of any leftover potential during transient operation is crucial. This paper proposes an approach to derive a transient feedforward (FF control system in an automated way. It relies on optimal control theory to solve a dynamic optimization problem for fast transients. A partially physics-based model is thereby used to replace the engine. From the optimal solutions, the relevant information is extracted and stored in maps spanned by the engine speed and the torque gradient. These maps complement the static control maps by accounting for the dynamic behavior of the engine. The procedure is implemented on a real engine and experimental results are presented along with the development of the methodology.

  11. Step-and-Shoot versus Compensator-based IMRT: Calculation and Comparison of Integral Dose in Non-tumoral and Target Organs in Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Kaveh Shirani Tak Abi

    2015-05-01

    Full Text Available Introduction Intensity-Modulated Radiotherapy (IMRT is becoming an increasingly routine treatment method. IMRT can be delivered by use of conventional Multileaf Collimators (MLCs and/or physical compensators. One of the most important factors in selecting an appropriate IMRT technique is integral dose. Integral dose is equal to the mean energy deposited in the total irradiated volume of the patient. The aim of the present study was to calculate and compare the integral dose in normal and target organs in two different procedures of IMRT: Step-and-Shoot (SAS and compensator-based IMRT. Materials and Methods In this comparative study, five patients with prostate cancer were selected. Module Integrated Radiotherapy System was applied, using three energy ranges. In both treatment planning methods, the integral dose dramatically decreased by increasing energy. Results Comparison of two treatment methods showed that on average, the integral dose of body in SAS radiation therapy was about 1.62% lower than that reported in compensator-based IMRT. In planning target volume, rectum, bladder, and left and right femoral heads, the integral doses for SAS method were 1.01%, 1.02%, 1.11%, 1.47%, and 1.40% lower than compensator-based IMRT, respectively. Conclusion Considering the treatment conditions, the definition of dose volume constraints for healthy tissues, and the equal volume of organs in both treatment methods, SAS radiation therapy by providing a lower integral dose seems to be more advantageous and efficient for prostate cancer treatment, compared to compensator-based IMRT.

  12. A 6-month supervised employer-based minimal exercise program for police officers improves fitness.

    Science.gov (United States)

    Rossomanno, Colleen I; Herrick, Jeffery E; Kirk, Stacie M; Kirk, Erik P

    2012-09-01

    The purpose of the study was to determine the effects of a 6-month supervised, job-specific moderate exercise program in police officers on body composition, cardiovascular and muscular fitness. Body weight (BW), body mass index (BMI), and cardiovascular and muscular fitness were assessed at baseline, after a 6-month supervised fitness program and at 12-month follow-up (18 months). One hundred sixty-five (n = 131 men and n = 34 women) young (mean ± SEM, 26.4 ± 1.9 years), overweight (BMI = 26.2 ± 1.2 kg·m) police officers participated. Aerobic exercise progressed from 3 d·wk, 20 minutes per session at 60% of the heart rate reserve (HRR) to 5 d·wk, 30 minutes per session at 75% of HRR at 3 months, and this level was maintained until 6 months. Muscular strength training progressed using 8 different calisthenics exercises from 3 d·wk, 2 sets of 5 repetitions using the participant's own BW to 5 d·wk, 3 sets of 15 repetitions of the participant's own BW at 3 months, and this level was maintained until 6 months. Cardiovascular and muscular fitness was measured using a 0.25-mile obstacle course incorporating various job-specific exercises and expressed as the physical abilities test (PAT) time. There was a significant reduction in BMI (-0.6 ± 0.2 kg·m, p police officers improves fitness and body composition after 6 months in both men and women, but continued supervision of exercise program may be necessary for maintenance of health benefits.

  13. Abdominal parametric perfusion imaging with respiratory motion-compensation based on contrast-enhanced ultrasound: In-vivo validation.

    Science.gov (United States)

    Wang, Diya; Xiao, Mengnan; Zhang, Yu; Wan, Mingxi

    2017-06-22

    Parametric perfusion imaging (PPI) based on dynamic contrast-enhanced ultrasound (DCEUS) is a multi-parametric functional method that is increasingly used to characterize the hemodynamic features of abdominal tumors. Periodic respiratory kinetics adversely affects the signal-to-clutter ratio (SCR) and accuracy of abdominal PPI. This study proposed respiratory motion-compensation (rMoCo) employing non-negative matrix factorization combined with fast block matching algorithm to effectively remove these disturbances on abdominal PPI, which was validated through in-vivo perfusion experiments. The mean calculation efficiency of rMoCo was improved by 83.6% when the algorithm was accelerated in a unique matching sequence, which was formed from dozens of DCEUS subsequences at the same respiratory phase. The horizontal and vertical displacements induced by respiratory kinetics were estimated to correct the extraction of time-intensity curves and the peak SNR remained at 22.58±2.90dB. Finally, the abdominal PPIs of four perfusion parameters were formed with non-negative rMoCo, and their SCR was improved by 3.99±0.49dB (pbenefits clinicians in providing accurate diagnoses and in developing appropriate therapeutic strategies for abdominal diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Step-size selection for split-step based nonlinear compensation with coherent detection in 112-Gb/s 16-QAM transmission

    Institute of Scientific and Technical Information of China (English)

    Chien-Yu Lin; Rameez Asif; Michael Holtmannspoetter; Bernhard Schmauss

    2012-01-01

    Non-uniform step-size distribution is implemented for split-step based nonlinear compensation in single-channel 112-Gb/s 16 quadrature amplitude modulation (QAM) transmission. Numerical simulations of the system including a 20x80 km uncompensated link are performed using logarithmic step size distribution to compensate signal distortions. 50% of reduction in number of steps with respect to using constant step sizes is observed. The performance is further improved by optimizing nonlinear calculating position (NLCP) in case of using constant step sizes while NLCP optimization becomes unnecessary when using logarithmic step sizes, which reduces the computational effort due to uniformly distributed nonlinear phase for all successive steps.%Non-uniform step-size distribution is implemented for split-step based nonlinear compensation in singlechannel 112-Gb/s 16 quadrature amplitude modulation (QAM) transmission.Numerical simulations of the system including a 20×80 km uncompensated link are performed using logarithmic step size distribution to compensate signal distortions.50% of reduction in number of steps with respect to using constant step sizes is observed.The performance is further improved by optimizing nonlinear calculating position (NLCP) in case of using constant step sizes while NLCP optimization becomes unnecessary when using logarithmic step sizes,which reduces the computational effort due to uniformly distributed nonlinear phase for all successive steps.

  15. Pipeline Bending Strain Measurement and Compensation Technology Based on Wavelet Neural Network

    Directory of Open Access Journals (Sweden)

    Rui Li

    2016-01-01

    Full Text Available The bending strain of long distance oil and gas pipelines may lead to instability of the pipeline and failure of materials, which seriously deteriorates the transportation security of oil and gas. To locate the position of the bending strain for maintenance, an Inertial Measurement Unit (IMU is usually adopted in a Pipeline Inspection Gauge (PIG. The attitude data of the IMU is usually acquired to calculate the bending strain in the pipe. However, because of the vibrations in the pipeline and other system noises, the resulting bending strain calculations may be incorrect. To improve the measurement precision, a method, based on wavelet neural network, was proposed. To test the proposed method experimentally, a PIG with the proposed method is used to detect a straight pipeline. It can be obtained that the proposed method has a better repeatability and convergence than the original method. Furthermore, the new method is more accurate than the original method and the accuracy of bending strain is raised by about 23% compared to original method. This paper provides a novel method for precisely inspecting bending strain of long distance oil and gas pipelines and lays a foundation for improving the precision of inspection of bending strain of long distance oil and gas pipelines.

  16. Novel infrared image enhancement technology based on the frequency compensation approach

    Science.gov (United States)

    Qi, Yuhua; He, Rulong; Lin, Haitao

    2016-05-01

    A novel infrared image enhancement method has been proposed in this paper. Our aim is to develop a detail enhancement method which is focused on the frequency feature of the image. The proposed method is following the most popular strategy of enhancing the infrared images nowadays, but concentrating on the frequency domain. Firstly, the original image is separated by a guided image filter into detail layer and the base layer. Quite unlike the traditional methods, we use the guided image filter to eliminate most of the noise and weak signal of the scenario. Then, by a designed iteration process, the higher frequency of the scenario will be calculated back and add to the detail layer. The noise will not be enhanced because the iteration is only focused on the leftover scenario frequency. We run many tests on the raw data captured by the 320 × 256 HgCdTe cooled thermal imager, and make a comparison between our approach with the previous method of bilateral filtering digital detail enhancement and guided image filtering digital detail enhancement. Figures and analytical data show that our method is better than the previous proposed researches. Our method could effectively process the infrared image with less noise and artifacts, which has potential applications in testing, manufacturing, chemical imaging, night vision, and surveillance security.

  17. A Secure, Social Media-Based "Case of the Month" Module in a Neurocritical Care Unit.

    Science.gov (United States)

    Witherspoon, Briana; Braunlin, Kathryn; Kumar, Avinash B

    2016-07-01

    Systems to meet the on-demand learning needs of nurses in intensive care units are not well studied beyond the traditional classroom models. To study the feasibility and effect of implementing an online discussion forum for nurses in a busy neuroscience intensive care unit. A baseline survey was done to highlight the areas of educational need in the unit. Freeform-a password-protected, online discussion forum supported by the university-was used for the pilot project. Freeform has functions similar to Facebook, with "likes," "follow," discussion/comment spaces, and the capacity for uploading images and files. A page called "All things NeuroCritical Care" was created. All nurses working in the intensive care unit were automatically enrolled. Clinical vignettes relevant to neurocritical care were posted once a month with 1 to 2 lead questions. All participation was voluntary, and topics were chosen on the basis of the needs survey. At the end of each case, a recent review article on the topic was posted for secure download. Eight sentinel diagnoses have been presented as clinical vignettes, and 34 of 76 members formally follow the page. The mean number of discussion strings per case is 8.3 posts. The number of unique visitors to the page during active case discussions exceeds 100. A secure, online, problem-based learning discussion format is a feasible point-of-care learning opportunity that can help overcome some of the traditional barriers to ongoing nursing education needs in a busy intensive care unit. ©2016 American Association of Critical-Care Nurses.

  18. Faculty Compensation Policies.

    Science.gov (United States)

    Silander, Fred

    1983-01-01

    Faculty compensation policy is seen as one means by which an institution influences the faculty to work toward institutional goals. Among the broad criteria for compensation are worth, equity, need, and market measures. Benefits and issues in compensation including differentials in compensation, merit, part-time instruction, etc. are discussed.…

  19. Precise tuning of the Curie temperature of (Ga,Mn)As-based magnetic semiconductors by hole compensation: Support for valence-band ferromagnetism

    Science.gov (United States)

    Zhou, Shengqiang; Li, Lin; Yuan, Ye; Rushforth, A. W.; Chen, Lin; Wang, Yutian; Böttger, R.; Heller, R.; Zhao, Jianhua; Edmonds, K. W.; Campion, R. P.; Gallagher, B. L.; Timm, C.; Helm, M.

    2016-08-01

    For the prototype diluted ferromagnetic semiconductor (Ga,Mn)As, there is a fundamental concern about the electronic states near the Fermi level, i.e., whether the Fermi level resides in a well-separated impurity band derived from Mn doping (impurity-band model) or in the valence band that is already merged with the Mn-derived impurity band (valence-band model). We investigate this question by carefully shifting the Fermi level by means of carrier compensation. We use helium-ion implantation, a standard industry technology, to precisely compensate the hole doping of GaAs-based diluted ferromagnetic semiconductors while keeping the Mn concentration constant. We monitor the change of Curie temperature (TC) and conductivity. For a broad range of samples including (Ga,Mn)As and (Ga,Mn)(As,P) with various Mn and P concentrations, we observe a smooth decrease of TC with carrier compensation over a wide temperature range while the conduction is changed from metallic to insulating. The existence of TC below 10 K is also confirmed in heavily compensated samples. Our experimental results are naturally explained within the valence-band picture.

  20. Engineering Compensations in Web Service Environment

    DEFF Research Database (Denmark)

    Schäfer, Micahel; Dolog, Peter; Nejdl, Wolfgang

    2007-01-01

    Business to business integration has recently been performed by employing Web service environments. Moreover, such environments are being provided by major players on the technology markets. Those environments are based on open specifications for transaction coordination. When a failure...... compensations based on forward recovery principles. We extend the existing Web service transaction coordination architecture and infrastructure in order to support flexible compensation operations. A contract-based approach is being used, which allows the specification of permitted compensations at runtime. We...

  1. A micro-optical system for endoscopy based on mechanical compensation paradigm using miniature piezo-actuation.

    Science.gov (United States)

    Cerveri, Pietro; Zazzarini, Cynthia Corinna; Patete, Paolo; Baroni, Guido

    2014-06-01

    The goal of the study was to investigate the feasibility of a novel miniaturized optical system for endoscopy. Fostering the mechanical compensation paradigm, the modeled optical system, composed by 14 lenses, separated in 4 different sets, had a total length of 15.55mm, an effective focal length ranging from 1.5 to 4.5mm with a zoom factor of about 2.8×, and an angular field of view up to 56°. Predicted maximum lens travel was less than 3.5mm. The consistency of the image plane height across the magnification range testified the zoom capability. The maximum predicted achromatic astigmatism, transverse spherical aberration, longitudinal spherical aberration and relative distortion were less than or equal to 25μm, 15μm, 35μm and 12%, respectively. Tests on tolerances showed that the manufacturing and opto-mechanics mounting are critical as little deviations from design dramatically decrease the optical performances. However, recent micro-fabrication technology can guarantee tolerances close to nominal design. A closed-loop actuation unit, devoted to move the zoom and the focus lens sets, was implemented adopting miniaturized squiggle piezo-motors and magnetic position encoders based on Hall effect. Performance results, using a prototypical test board, showed a positioning accuracy of less than 5μm along a lens travel path of 4.0mm, which was in agreement with the lens set motion features predicted by the analysis. In conclusion, this study demonstrated the feasibility of the optical design and the viability of the actuation approach while tolerances must be carefully taken into account.

  2. Analytic signal phase-based myocardial motion estimation in tagged MRI sequences by a bilinear model and motion compensation.

    Science.gov (United States)

    Wang, Liang; Basarab, Adrian; Girard, Patrick R; Croisille, Pierre; Clarysse, Patrick; Delachartre, Philippe

    2015-08-01

    Different mathematical tools, such as multidimensional analytic signals, allow for the calculation of 2D spatial phases of real-value images. The motion estimation method proposed in this paper is based on two spatial phases of the 2D analytic signal applied to cardiac sequences. By combining the information of these phases issued from analytic signals of two successive frames, we propose an analytical estimator for 2D local displacements. To improve the accuracy of the motion estimation, a local bilinear deformation model is used within an iterative estimation scheme. The main advantages of our method are: (1) The phase-based method allows the displacement to be estimated with subpixel accuracy and is robust to image intensity variation in time; (2) Preliminary filtering is not required due to the bilinear model. The proposed algorithm, integrating phase-based optical flow motion estimation and the combination of global motion compensation with local bilinear transform, allows spatio-temporal cardiac motion analysis, e.g. strain and dense trajectory estimation over the cardiac cycle. Results from 7 realistic simulated tagged magnetic resonance imaging (MRI) sequences show that our method is more accurate compared with state-of-the-art method for cardiac motion analysis and with another differential approach from the literature. The motion estimation errors (end point error) of the proposed method are reduced by about 33% compared with that of the two methods. In our work, the frame-to-frame displacements are further accumulated in time, to allow for the calculation of myocardial Lagrangian cardiac strains and point trajectories. Indeed, from the estimated trajectories in time on 11 in vivo data sets (9 patients and 2 healthy volunteers), the shape of myocardial point trajectories belonging to pathological regions are clearly reduced in magnitude compared with the ones from normal regions. Myocardial point trajectories, estimated from our phase-based analytic

  3. 12 CFR 918.3 - Compensation policy requirements.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Compensation policy requirements. 918.3 Section... LOAN BANKS BANK DIRECTOR COMPENSATION AND EXPENSES § 918.3 Compensation policy requirements. Payment to directors under each Bank's policy on director compensation may be based upon factors that the...

  4. Distortions identification and compensation based on artificial neural networks using symmetrical components of the voltages and the currents

    Energy Technology Data Exchange (ETDEWEB)

    Flieller, D. [Institut National Superieur des Sciences Appliquees de Strasbourg, Laboratoire GREEN (UMR 7037, CNRS) Antenne de Strasbourg, 24 Bd de la Victoire, 67084 Strasbourg Cedex (France); Ould Abdeslam, D.; Wira, P.; Merckle, J. [Universite de Haute-Alsace, Laboratoire MIPS-TROP, 4 rue des Freres Lumiere, 68093 Mulhouse Cedex (France)

    2009-07-15

    The problem of harmonics identifying and compensating has been of great interest in recent years. A new neural identification scheme for an active power filter (APF) is proposed. This scheme identifies the direct, inverse and zero sequence components of both the voltages and the currents of the power network. The components result from a new and generic decomposition of a three-phase signal which can be either the voltage or the current. For one signal, the direct components extraction requires two independent Adaline networks, and the inverse components extraction two other Adalines. The voltage and current components are used to on-line compute the instantaneous direct, inverse and zero sequence powers. The proposed decomposition is a new formulation of the instantaneous powers and is also appropriate for unbalanced systems. The reference compensation currents can be determined according to different compensation objectives. The resulting compensation currents are then re-injected phase-opposite through the APF in real-time. The performance is evaluated through several simulation examples and through different experiments. The results show that the proposed neural method outperforms other methods, such as the conventional instantaneous power theory. (author)

  5. Position control of a single pneumatic artificial muscle with hysteresis compensation based on modified Prandtl-Ishlinskii model.

    Science.gov (United States)

    Zang, Xizhe; Liu, Yixiang; Heng, Shuai; Lin, Zhenkun; Zhao, Jie

    2017-01-01

    High-performance position control of pneumatic artificial muscles is limited by their inherent nonlinearity and hysteresis. This study aims to model the length/pressure hysteresis of a single pneumatic artificial muscle and to realize its accurate position tracking control with forward hysteresis compensation. The classical Prandtl-Ishlinskii model is widely used in hysteresis modelling and compensation. But it is only effective for symmetric hysteresis. Therefore, a modified Prandtl-Ishlinskii model is built to characterize the asymmetric length/pressure hysteresis of a single pneumatic artificial muscle, by replacing the classical play operators with two more flexible elementary operators to independently describe the ascending branch and descending branch of hysteresis loops. On the basis, a position tracking controller, which is composed of cascade forward hysteresis compensation and simple proportional pressure controller, is designed for the pneumatic artificial muscle. Experiment results show that the MPI model can reproduce the length/pressure hysteresis of the pneumatic artificial muscle, and the proposed controller for the pneumatic artificial muscle can track the reference position signals with high accuracy. By modelling the length/pressure hysteresis with the modified Prandtl-Ishlinskii model and using its inversion for compensation, precise position control of a single pneumatic artificial muscle is achieved.

  6. The Micropolitics of Implementing a School-Based Bonus Policy: The Case of New York City's Compensation Committees

    Science.gov (United States)

    Marsh, Julie

    2012-01-01

    This article examines the micropolitics of implementing New York City's Schoolwide Performance Bonus Program and school governance bodies (Compensation Committees) that determined distribution of school-level rewards among personnel. Drawing on a two-year, mixed-methods study, the author finds that although most participants surveyed described a…

  7. Predictability of the monthly North Atlantic Oscillation index based on fractal analyses and dynamic system theory

    Science.gov (United States)

    Martínez, M. D.; Lana, X.; Burgueño, A.; Serra, C.

    2010-03-01

    The predictability of the monthly North Atlantic Oscillation, NAO, index is analysed from the point of view of different fractal concepts and dynamic system theory such as lacunarity, rescaled analysis (Hurst exponent) and reconstruction theorem (embedding and correlation dimensions, Kolmogorov entropy and Lyapunov exponents). The main results point out evident signs of randomness and the necessity of stochastic models to represent time evolution of the NAO index. The results also show that the monthly NAO index behaves as a white-noise Gaussian process. The high minimum number of nonlinear equations needed to describe the physical process governing the NAO index fluctuations is evidence of its complexity. A notable predictive instability is indicated by the positive Lyapunov exponents. Besides corroborating the complex time behaviour of the NAO index, present results suggest that random Cantor sets would be an interesting tool to model lacunarity and time evolution of the NAO index.

  8. Predictability of the monthly North Atlantic Oscillation index based on fractal analyses and dynamic system theory

    Directory of Open Access Journals (Sweden)

    M. D. Martínez

    2010-03-01

    Full Text Available The predictability of the monthly North Atlantic Oscillation, NAO, index is analysed from the point of view of different fractal concepts and dynamic system theory such as lacunarity, rescaled analysis (Hurst exponent and reconstruction theorem (embedding and correlation dimensions, Kolmogorov entropy and Lyapunov exponents. The main results point out evident signs of randomness and the necessity of stochastic models to represent time evolution of the NAO index. The results also show that the monthly NAO index behaves as a white-noise Gaussian process. The high minimum number of nonlinear equations needed to describe the physical process governing the NAO index fluctuations is evidence of its complexity. A notable predictive instability is indicated by the positive Lyapunov exponents. Besides corroborating the complex time behaviour of the NAO index, present results suggest that random Cantor sets would be an interesting tool to model lacunarity and time evolution of the NAO index.

  9. A 30-Minute, Monthly, Live, Webinar-Based Journal Club Activity Alters the Self-Reported Behaviors of Dermatologic Surgeons.

    Science.gov (United States)

    Zavell, Amy E; Greenberg, Judah N; Alam, Murad; Armbrecht, Eric S; Maher, Ian A

    2017-09-01

    Journal clubs provide a way to communicate advances in recent literature. In outpatient surgical subspecialties, such as dermatologic surgery, physicians may face challenges in finding or attending meetings pertinent to their practice. To assess the utility of a live web-based journal club in dermatologic surgery. Monthly 30-minute journal club sessions covering 5 to 6 scholarly articles. Anonymous surveys were used to evaluate the utility and self-reported learning associated with each meeting. From December 2012 to February 2015, 117 articles were reviewed. Survey data were acquired monthly, apart from 5 months of missing data. On average, the survey response rate was 37% (range: 7%-82%), with an average of 17 participants per monthly session (range: 9-25). The mean monthly usefulness score was 83.7 (101-point scale), with participants scoring their likelihood of returning in the future as 96.2 (0 = not likely, 100 = extremely likely). At each session, a mean of 68% of participants felt that at least one article would change their practice of medicine. A monthly online and telephonic journal club may be a practical and effective way to inform dermatologic surgeons of new developments in high impact literature and may influence improvements in individual practice.

  10. Effects of the Sense-Based Science Education Program on Scientific Process Skills of Children Aged 60-66 Months

    Science.gov (United States)

    Tekerci, Hacer; Kandir, Adalet

    2017-01-01

    Purpose: This study aimed to examine the effects of the Sense-Based Science Education Program on 60-66 months old children's scientific process skills. Research Methods: In this study, which carries experimental attribute features, the pre-test/final-test/observing-test control grouped experimental pattern, and qualitative research were used.…

  11. Temperature-compensated distributed hydrostatic pressure sensor with a thin-diameter polarization-maintaining photonic crystal fiber based on Brillouin dynamic gratings.

    Science.gov (United States)

    Teng, Lei; Zhang, Hongying; Dong, Yongkang; Zhou, Dengwang; Jiang, Taofei; Gao, Wei; Lu, Zhiwei; Chen, Liang; Bao, Xiaoyi

    2016-09-15

    A temperature-compensated distributed hydrostatic pressure sensor based on Brillouin dynamic gratings (BDGs) is proposed and demonstrated experimentally for the first time, to the best of our knowledge. The principle is to measure the hydrostatic pressure induced birefringence changes through exciting and probing the BDGs in a thin-diameter pure silica polarization-maintaining photonic crystal fiber. The temperature cross-talk to the hydrostatic pressure sensing can be compensated through measuring the temperature-induced Brillouin frequency shift (BFS) changes using Brillouin optical time-domain analysis. A distributed measurement of hydrostatic pressure is demonstrated experimentally using a 4-m sensing fiber, which has a high sensitivity, with a maximum measurement error less than 0.03 MPa at a 20-cm spatial resolution.

  12. Compensation temperatures of mixed spin-2 and spin-((5)/(2)) ferrimagnetic system with interlayer coupling; a study of a molecular-based magnet

    CERN Document Server

    Zhang Qi

    2002-01-01

    Compensation points of layer system consisting of mixed spin-2 and spin-((5)/(2)) ferrimagnetic honeycomb lattice layers which are coupled together with two kinds of positive interlayer coupling are examined by the use of the effective-field theory with correlations (EFT). In particular, the effects of interlayer coupling and a positive crystal-field constant of the spin-2 ions on the compensation temperature are investigated, in order to clarify the characteristic behavior of the temperature dependence of the total magnetization M. This is related to the experimental works of a molecular-based magnetic multilayer film, N(n-C sub 4 H sub 9) sub 4 Fe sup I sup I Fe sup I sup I sup I (C sub 2 O sub 4) sub 3. A comparison is made between the results in this paper and those in a previous work obtained by using Monte-Carlo simulations.

  13. Three-directional motion compensation-based novel-look-up-table for video hologram generation of three-dimensional objects freely maneuvering in space.

    Science.gov (United States)

    Dong, Xiao-Bin; Kim, Seung-Cheol; Kim, Eun-Soo

    2014-07-14

    A new three-directional motion compensation-based novel-look-up-table (3DMC-NLUT) based on its shift-invariance and thin-lens properties, is proposed for video hologram generation of three-dimensional (3-D) objects moving with large depth variations in space. The input 3-D video frames are grouped into a set of eight in sequence, where the first and remaining seven frames in each set become the reference frame (RF) and general frames (GFs), respectively. Hence, each 3-D video frame is segmented into a set of depth-sliced object images (DOIs). Then x, y, and z-directional motion vectors are estimated from blocks and DOIs between the RF and each of the GFs, respectively. With these motion vectors, object motions in space are compensated. Then, only the difference images between the 3-directionally motion-compensated RF and each of the GFs are applied to the NLUT for hologram calculation. Experimental results reveal that the average number of calculated object points and the average calculation time of the proposed method have been reduced compared to those of the conventional NLUT, TR-NLUT and MPEG-NLUT by 38.14%, 69.48%, and 67.41% and 35.30%, 66.39%, and 64.46%, respectively.

  14. Dosimetric study for cervix carcinoma treatment using intensity modulated radiation therapy (IMRT) compensation based on 3D intracavitary brachytherapy technique.

    Science.gov (United States)

    Yin, Gang; Wang, Pei; Lang, Jinyi; Tian, Yin; Luo, Yangkun; Fan, Zixuan; Tam, Kin Yip

    2016-06-01

    Intensity modulated radiation therapy (IMRT) compensation based on 3D high-dose-rate (HDR) intracavitary brachytherapy (ICBT) boost technique (ICBT + IMRT) has been used in our hospital for advanced cervix carcinoma patients. The purpose of this study was to compare the dosimetric results of the four different boost techniques (the conventional 2D HDR intracavitary brachytherapy [CICBT], 3D optimized HDR intracavitary brachytherapy [OICBT], and IMRT-alone with the applicator in situ). For 30 patients with locally advanced cervical carcinoma, after the completion of external beam radiotherapy (EBRT) for whole pelvic irradiation 45 Gy/25 fractions, five fractions of ICBT + IMRT boost with 6 Gy/fractions for high risk clinical target volume (HRCTV), and 5 Gy/fractions for intermediate risk clinical target volume (IRCTV) were applied. Computed tomography (CT) and magnetic resonance imaging (MRI) scans were acquired using an in situ CT/MRI-compatible applicator. The gross tumor volume (GTV), the high/intermediate-risk clinical target volume (HRCTV/IRCTV), bladder, rectum, and sigmoid were contoured by CT scans. For ICBT + IMRT plan, values of D90, D100 of HRCTV, D90, D100, and V100 of IRCTV significantly increased (p < 0.05) in comparison to OICBT and CICBT. The D2cc values for bladder, rectum, and sigmoid were significantly lower than that of CICBT and IMRT alone. In all patients, the mean rectum V60 Gy values generated from ICBT + IMRT and OICBT techniques were very similar but for bladder and sigmoid, the V60 Gy values generated from ICBT + IMRT were higher than that of OICBT. For the ICBT + IMRT plan, the standard deviations (SD) of D90 and D2cc were found to be lower than other three treatment plans. The ICBT + IMRT technique not only provides good target coverage but also maintains low doses (D2cc) to the OAR. ICBT + IMRT is an optional technique to boost parametrial region or tumor of large size and irregular shape when intracavitary/interstitial brachytherapy

  15. Linearization and Control of Series-Series Compensated Inductive Power Transfer System Based on Extended Describing Function Concept

    Directory of Open Access Journals (Sweden)

    Kunwar Aditya

    2016-11-01

    Full Text Available The extended describing function (EDF is a well-known method for modelling resonant converters due to its high accuracy. However, it requires complex mathematical formulation effort. This paper presents a simplified non-linear mathematical model of series-series (SS compensated inductive power transfer (IPT system, considering zero-voltage switching in the inverter. This simplified mathematical model permits the user to derive the small-signal model using the EDF method, with less computational effort, while maintaining the accuracy of an actual physical model. The derived model has been verified using a frequency sweep method in PLECS. The small-signal model has been used to design the voltage loop controller for a SS compensated IPT system. The designed controller was implemented on a 3.6 kW experimental setup, to test its robustness.

  16. Reduction of Thermal Residual Stresses in Advanced Metallic Composites Based upon a Compensating/Compliant Layer Concept

    Science.gov (United States)

    Arnold, S. M.; Arya, V. K.; Melis, M. E.

    1992-01-01

    A detailed parametric study is carried out to investigate the viability of the recently proposed compensating/compliant layer concept (i.e., the insertion of an interface material between SiC fiber and metal matrix to reduce or eliminate the residual stress buildup during cooling of the composite). The study uses a finite-element concentric cylinder model with generalized plane strain end conditions and free boundary conditions, assuming the SiC fiber to be isotropic and linear elastic and the compliant layer cylinder and matrix (Ti3Al + Nb) cylinder to be isotropic and bilinear elastic-plastic. Results show that a compensating/compliant layer acts to reduce in-plane residual stresses within the fiber and the matrix and, therefore, reduces radial cracking. However, this decrease in in-plane stresses is accompanied by an increase of longitudinal stress, which may initiate longitudinal cracking.

  17. Reactive power and harmonic compensation based on the generalized instantaneous reactive power theory for three-phase power systems

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Fang Zheng [Tennessee Univ., Knoxville, TN (United States); Lai, Jih-Sheng [Oak Ridge National Lab., TN (United States)

    1996-10-01

    A generalized theory of instantaneous reactive power for three-phase power systems is proposed in this paper. This theory gives a generalized definition of instantaneous reactive power, which is valid for sinusoidal or nonsinusoidal, balanced or unbalanced, three- phase power systems with or without zero-sequence currents and/or voltages. The properties and physical meanings of the newly defined instantaneous reactive power are discussed in detail. With this new reactive power theory, it is very easy to calculate and decompose all components, such as fundamental active/reactive power and current, harmonic current, etc. Reactive power and/or harmonic compensation systems for a three-phase distorted power system with and without zero-sequence components in the source voltage and/or load current are then used as examples to demonstrate the measurement, decomposition, and compensation of reactive power and harmonics.

  18. Evaluation of Coordinate Compensator Structure Based on Power Injection Model for Loading Margin Enhancement in Power Systems

    Directory of Open Access Journals (Sweden)

    Reza Sedaghati

    2013-09-01

    Full Text Available In this paper, the structure of Hybrid Power Flow Controller (HPFC is proposed in order to improve static voltage stability characteristics. HPFC forms a hybrid controller using IPFC series converters as a hybrid with existing parallel and passive compensator (SVC in power system. Utilization of hybrid structures makes it possible to use converters for improving performance of both old and existing compensators in power networks. In this study, the power injection model (PIM is used to model the hybrid power flow controller in Newton load flow. The aforementioned model is simulated in MATLAB software. The P-V curves of PQ buses of a typical system are evaluated by a continuous power flow (CPF method to analyses the effect of this controller on static voltage stability characteristics. Meanwhile, SVC as existing devices in the system and UPFC and IPFC as state-of-the-art compensator devices are compared with the proposed hybrid structure. The amount of active and reactive power loss and improvement of loading limit of the system are used as main parameters in our comparison.

  19. Monthly distribution of diurnal total column ozone based on the 2011 satellite data in Peninsular Malaysia

    Directory of Open Access Journals (Sweden)

    Jasim M. Rajab

    2013-06-01

    Full Text Available Ozone (O3 is a radiatively active trace gas, and naturally present in our atmosphere, that plays a prominent role in atmosphere heating rates due to its good capability to absorb the infrared radiation. O3 occurs both naturally in the Earth’s upper atmosphere and at the ground level. As we breathe the air on Earth, O3 causes damage to the lung tissue and plants as it is an injurious pollutant; it is a major constituent of smog. The atmospheric O3 observations can only be made on global and continental scales by remote sensing instruments situated in the space. The satellite-borne sensor, namely the Atmospheric Infrared Sounder (AIRS included on the EOS Aqua satellite, was employed to investigate the spatial and temporal variations of diurnal total column Ozone burden over Peninsular Malaysia for the year 2011. The analysis of O3 above five dispersed stations in the study area shows the seasonal variation in the O3 fluctuated considerably observed between NEM and SWM seasons. The mean and the standard deviation of monthly O3 was 244.7 ± 26.8 DU for the entire period, and O3 values strongly correlated with weather conditions. The highest O3 values occurred over industrial and congested urban zones (271.5 DU on May at Johor. The lowest O3 values were observed during NEM in the pristine coastal environment on December at Kuantan (217 DU; at 3.45°N, 103.20°E. The O3 has an inverse relationship with the rain and positive with temperature. The monthly O3 maps were obtained from the NASA-operated Giovanni portal (http://disc.sci.gsfc.nasa.gov/giovanni. The AIRS data and the satellite measurements are able to measure the increase of the atmosphere O3 concentrations over different areas.

  20. Study on the Type Division of the Ecological Compensation and Pollution Compensation Basing on the Section of the Cross-Boundary River's Responsibliè Target Assessment%基于流域跨界责任目标考核断面的生态补偿与污染赔偿类型划分研究

    Institute of Scientific and Technical Information of China (English)

    梁亦欣; 于鲁冀; 葛丽燕

    2012-01-01

    With the case study of the river basin ecological compensation and pollution compensation pilot in Henan Province, this paper discusses the present research situation and existence questions of the domestic river basin ecological compensation and pollution compensation's type classification. Through combining with river features and outstanding issues of Henan, it carries out technical methods study on watershed ecological compensation and pollution compensation classification which based on target value of the watershed responsibility assessment section and attaches importance to operability. The paper focuses on technical roadmap, classification principle and classification method of ecological compensation and pollution compensation type, furthermore, and takes Henan as an illustration to make study on watershed ecological compensation pollution compensation classification. At last, it turns out that watershed ecological compensation and pollution compensation classification which based on target value of the watershed responsibility assessment section is more operational and practical as well as dynamic in space and time when compared with watershed ecological compensation and pollution compensation classification which based on watershed scale and prominent environmental and development issues because it is more in-depth and detailed. This is not only beneficial for partition of the responsibility body and determination of compensation subject and object, but also link between policies of ecological compensation mechanism and current environmental protection responsibility target assessment system, what's more, it impels work of local governments and water pollution prevention and control.%以河南省流域生态补偿与污染赔偿试点研究为例,探讨了国内流域生态补偿与污染赔偿类型划分研究现状及存在问题,结合河南省流域特征和突出问题,以可操作性为着力点,开展了基于流域责任目标考核断面目标

  1. Essays in Executive Compensation

    NARCIS (Netherlands)

    D. Zhang (Dan)

    2012-01-01

    textabstractThis dissertation focuses on how executive compensation is designed and its implications for corporate finance and government regulations. Chapter 2 analyzes several proposals to restrict CEO compensation and calibrates two models of executive compensation that describe how firms would r

  2. Essays in Executive Compensation

    NARCIS (Netherlands)

    D. Zhang (Dan)

    2012-01-01

    textabstractThis dissertation focuses on how executive compensation is designed and its implications for corporate finance and government regulations. Chapter 2 analyzes several proposals to restrict CEO compensation and calibrates two models of executive compensation that describe how firms would

  3. A dual-blue light-emitting diode based on strain-compensated InGaN-AlGaN/GaN quantum wells

    Institute of Scientific and Technical Information of China (English)

    Yan Qi-Rong; Yan Qi-Ang; Shi Pei-Pei; Niu Qiao-Li; Li Shu-Ti; Zhang Yong

    2013-01-01

    A strain-compensated InGaN quantum well (QW) active region employing a tensile A1GaN barrier is analyzed.Its spectral stability and efficiency droop for a dual-blue light-emitting diode (LED) are improved compared with those of the conventional InGaN/GaN QW dual-blue LEDs based on a stacking structure of two In0.18Ga0.82N/GaN QWs and two In0.12Ga0.88N/GaN QWs on the same sapphire substrate.It is found that the optimal performance is achieved when the AI composition of the strain-compensated A1GaN layer is 0.12 in blue QW and 0.21 in blue-violet QW.The improvement performance can be attributed to the strain-compensated InGaN-AlGaN/GaN QW,which can provide a better carrier confinement and effectively reduce leakage current.

  4. Error Compensation of Posture Measurement for Bus/Coach Based on MEMS Gyroscope%客车姿态测量中的MEMS陀螺误差补偿

    Institute of Scientific and Technical Information of China (English)

    万涛

    2016-01-01

    针对客车姿态测量中使用MEMS陀螺误差较大问题,基于AR模型方法,采集MEMS陀螺原始信号并进行预处理,从而辨识出AR模型参数;利用该模型对陀螺信号进行误差补偿,计算出陀螺的较精确值,并通过实验验证。结果表明,所提出的方法能够有效地减小误差,能够用于客车姿态的MEMS陀螺测量误差的补偿。%Aiming at the bigger error of the MEMS gyroscope used in the posture measurement for buses/coaches, a MEMS gyroscope error compensation method based on the AR model is proposed. MEMS gyroscope signal is col-lected and pre-processed in order to identify the parameters of AR model. The error of the gyroscope signal is com-pensated by use of this model, and the accurate signal value is calculated and validated through the test. The results show that the proposed method can effectively reduce the error, and can be used for the compensation of MEMS gy-roscope error in the posture measurement for buses/coaches.

  5. Temperature error compensation for load cell based on RBFNN*%基于RBFNN的称重传感器温度误差补偿

    Institute of Scientific and Technical Information of China (English)

    杨进宝; 倪芳英; 张建军

    2011-01-01

    Load cell has nonlinear error because of different ambient temperature in work, and it is necessary to compensate. The principle of temperature error of load cell is illustrated, and a method for compensating this error based on radial basis function neural network (RBFNN) is proposed. The training algorithm of RBFNN is described. Using this proposed temperature error compensation method and the load cell which the weighing range is 100 kg,the experiments are implemented under 0 ~60℃. The results show that temperature errors of load cell are decreased, and its weighing accuracy is increased.%称重传感器存在因环境温度不同导致的非线性误差,需要进行补偿.阐述了称重传感器的温度误差机理,提出了一种基于径向基函数神经网络(RBFNN)的称重传感器温度误差补偿方法,并给出了训练算法.采用该方法,利用量程为100kg的称重传感器,在0~60℃范围内进行温度误差补偿实验.实验表明:采用这种方法补偿后,称重传感器温度误差大大减少,提高了称重准确度.

  6. A 24-month evaluation of amalgam and resin-based composite restorations

    DEFF Research Database (Denmark)

    McCracken, Michael S; Gordan, Valeria V; Litaker, Mark S

    2013-01-01

    Knowing which factors influence restoration longevity can help clinicians make sound treatment decisions. The authors analyzed data from The National Dental Practice-Based Research Network to identify predictors of early failures of amalgam and resin-based composite (RBC) restorations....

  7. SU-E-T-92: Achieving Desirable Lung Doses in Total Body Irradiation Based On in Vivo Dosimetry and Custom Tissue Compensation

    Energy Technology Data Exchange (ETDEWEB)

    Cui, G; Shiu, A; Zhou, S; Cui, J; Ballas, L [Univ Southern California, Los Angeles, CA (United States)

    2015-06-15

    Purpose: To achieve desirable lung doses in total body irradiation (TBI) based on in vivo dosimetry and custom tissue compensation. Methods: The 15 MV photon beam of a Varian TrueBeam STx linac was used for TBI. Patients were positioned in the lateral decubitus position for AP/PA treatment delivery. Dose was calculated using the midpoint of the separation distance across the patient’s umbilicus. Patients received 200 cGy twice daily for 3 days. The dose rate at the patient’s midplane was approximately 10 cGy/min. Cerrobend blocks with a 5-HVL thickness were used for the primary lung shielding. A custom styrofoam holder for rice-flour filled bags was created based on the lung block cutouts. This was used to provide further lung shielding based on in vivo dose measurements. Lucite plates and rice-flour bags were placed in the head, neck, chest, and lower extremity regions during the treatment to compensate for the beam off-axis output variations. Two patients were included in the study. Patients 1 and 2 received a craniospinal treatment (1080 cGy) and a mediastinum treatment (2520 cGy), respectively, before the TBI. During the TBI nanoDot dosimeters were placed on the patient skin in the forehead, neck, umbilicus, and lung regions for dose monitoring. The doses were readout immediately after the treatment. Based on the readings, fine tuning of the thickness of the rice-flour filled bags was exploited to achieve the desirable lung doses. Results: For both patients the mean lung doses, which took into consideration all treatments, were controlled within 900 +/−10% cGy, as desired. Doses to the forehead, neck, and umbilicus were achieved within +/−10% of the prescribed dose (1200 cGy). Conclusion: A reliable and robust method was developed to achieve desirable lung doses and uniform body dose in TBI based on in vivo dosimetry and custom tissue compensator.

  8. Seigniorage Compensation for Swaziland and Policy Implication.

    OpenAIRE

    Mkhonta, Simiso F.

    1992-01-01

    Seigniorage compensation for Swaziland is found to depend on Emalangeni in circulation in Swaziland besides the obvious effect of an increase in ZAR/Rands in circulation in South Africa. Where a percent increase in Emalangeni in circulation in Swaziland at time t decreases seigniorage compensation by 0.186 percent and a percent increase in Emalangeni in circulation at time t-1 decreases seigniorage compensation by 0.134 percent through both substitution and base effects respectively. Thus a...

  9. Change in well-being amongst participants in a four-month pedometer-based workplace health program.

    Science.gov (United States)

    Freak-Poli, Rosanne L A; Wolfe, Rory; Wong, Evelyn; Peeters, Anna

    2014-09-15

    There is increasing uptake of workplace physical activity programs to prevent chronic disease. While they are frequently evaluated for improvement in biomedical risk factors there has been little evaluation of additional benefits for psychosocial health. We aimed to evaluate whether participation in a four-month, team-based, pedometer-based workplace health program known to improve biomedical risk factors is associated with an improvement in well-being, immediately after the program and eight-months after program completion. At baseline (2008), 762 adults (aged 40 ± 10 SD years, 42% male) employed in primarily sedentary occupations and voluntarily enrolled in a physical activity program were recruited from ten Australian worksites. Data was collected at baseline, at the completion of the four-month program and eight-months after program completion. The outcome was the WHO-Five Well-being Index (WHO-5), a self-administered five-item scale that can be dichotomised as 'poor' (less than 52%) or 'positive' (more than or equal to 52%) well-being. At baseline, 75% of participants had positive well-being (mean: 60 ± 19 SD WHO-5 units). On average, well-being improved immediately after the health program (+3.5 units, p workplace programs, such as the one evaluated here, also has the potential to improve well-being.

  10. Regional infant brain development: an MRI-based morphometric analysis in 3 to 13 month olds.

    Science.gov (United States)

    Choe, Myong-Sun; Ortiz-Mantilla, Silvia; Makris, Nikos; Gregas, Matt; Bacic, Janine; Haehn, Daniel; Kennedy, David; Pienaar, Rudolph; Caviness, Verne S; Benasich, April A; Grant, P Ellen

    2013-09-01

    Elucidation of infant brain development is a critically important goal given the enduring impact of these early processes on various domains including later cognition and language. Although infants' whole-brain growth rates have long been available, regional growth rates have not been reported systematically. Accordingly, relatively less is known about the dynamics and organization of typically developing infant brains. Here we report global and regional volumetric growth of cerebrum, cerebellum, and brainstem with gender dimorphism, in 33 cross-sectional scans, over 3 to 13 months, using T1-weighted 3-dimensional spoiled gradient echo images and detailed semi-automated brain segmentation. Except for the midbrain and lateral ventricles, all absolute volumes of brain regions showed significant growth, with 6 different patterns of volumetric change. When normalized to the whole brain, the regional increase was characterized by 5 differential patterns. The putamen, cerebellar hemispheres, and total cerebellum were the only regions that showed positive growth in the normalized brain. Our results show region-specific patterns of volumetric change and contribute to the systematic understanding of infant brain development. This study greatly expands our knowledge of normal development and in future may provide a basis for identifying early deviation above and beyond normative variation that might signal higher risk for neurological disorders.

  11. 20 CFR 211.12 - Compensation credited for title VII benefits.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Compensation credited for title VII benefits... RETIREMENT ACT CREDITABLE RAILROAD COMPENSATION § 211.12 Compensation credited for title VII benefits... as compensation only for the month in which the employee first filed an application for benefits...

  12. 基于相控投切技术的无功补偿装置%Reactive Power Compensation Device Based on Phase-Controlled Switching Technology

    Institute of Scientific and Technical Information of China (English)

    汪玉凤; 王静; 许晓禹; 费翔

    2013-01-01

    In order to reduce inrush current and over-voltage which caused by random switch capacitors during reactive power compensation in coal mine power network,this paper designs a kind of reactive power compensation device based on promising“soft switch”technology that is phase-controlled switching technology, takes long life, low cost vacuum contactors with permanent magnetic actuator as switching ,this actuator has little action time dispersion than traditional spring actuator and electromagnetic actuator, in order to meet action time high degree of consistency, this paper compensates vacuum contactors action time dispersion, uses modular ideas to design reactive power compensation system structure diagram,together with the appropriate control strategy, completion the capacitor bank switching at a predetermined phase.finally this system makes experiment test in certain mine coal 6KV power network,experiment results show that phase-controlled switching technology of reactive power compensation effect is unmatched by traditional others methods, practice proved that this system has a certain value.%  为了减小煤矿电网在无功补偿时随机投切电容器组给电网带来的涌流及过电压,设计了一套以具有发展前景的“软开关”技术即相控技术为根基的无功补偿装置,采用寿命长、成本低的带有永磁机构的真空接触器作为投切开关,该机构较传统的弹簧机构和电磁机构动作分散性小,为满足动作时间高度一致,对真空接触器动作时间的分散性进行有效补偿,并采用模块化的思想理念建立系统整体结构,采取适当的控制策略完成预期位置投切。最后本系统进行了仿真,并在某矿6kv 电网中进行了实验测试,仿真和实验结果都表明本系统能有效的补偿系统无功,有一定的应用价值。

  13. Enthalpy-entropy compensation in protein unfolding

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Enthalpy-entropy compensation was found to be a universal law in protein unfolding based on over 3 000 experimental data. Water molecular reorganization accompanying the protein unfolding was suggested as the origin of the enthalpy-entropy compensation in protein unfolding. It is indicated that the enthalpy-entropy compensation constitutes the physical foundation that satisfies the biological need of the small free energy changes in protein unfolding, without the sacrifice of the bio-diversity of proteins. The enthalpy-entropy compensation theory proposed herein also provides valuable insights into the Privalov's puzzle of enthalpy and entropy convergence in protein unfolding.

  14. Employment-based reinforcement of adherence to oral naltrexone in unemployed injection drug users: 12-month outcomes.

    Science.gov (United States)

    Dunn, Kelly; DeFulio, Anthony; Everly, Jeffrey J; Donlin, Wendy D; Aklin, Will M; Nuzzo, Paul A; Leoutsakos, Jeannie-Marie S; Umbricht, Annie; Fingerhood, Michael; Bigelow, George E; Silverman, Kenneth

    2015-06-01

    Oral naltrexone could be a promising relapse-prevention pharmacotherapy for recently detoxified opioid-dependent patients; however, interventions are often needed to promote adherence with this treatment approach. We recently conducted a study to evaluate a 26-week employment-based reinforcement intervention of oral naltrexone in unemployed injection drug users (Dunn et al., 2013). Participants were randomly assigned into a contingency (n = 35) group required to ingest naltrexone under staff observation to gain entry into a therapeutic workplace or a prescription (n = 32) group given a take-home supply of oral naltrexone and access to the workplace without observed ingestion. Monthly urine samples were collected and analyzed for evidence for naltrexone adherence, opioid use, and cocaine use. As previously reported, contingency participants provided significantly more naltrexone-positive urine samples than prescription participants during the 26-week intervention period. The goal of this current study is to report the 12-month outcomes, which occurred 6 months after the intervention ended. Results at the 12-month visit showed no between-groups differences in naltrexone-positive, opioid-negative, or cocaine-negative urine samples and no participant self-reported using naltrexone at the follow-up visit. These results show that even after a period of successfully reinforced oral naltrexone adherence, longer-term naltrexone use is unlikely to be maintained after reinforcement contingencies are discontinued. (PsycINFO Database Record

  15. Engineering Compensations in Web Service Environment

    DEFF Research Database (Denmark)

    Schäfer, Micahel; Dolog, Peter; Nejdl, Wolfgang

    2007-01-01

    compensations based on forward recovery principles. We extend the existing Web service transaction coordination architecture and infrastructure in order to support flexible compensation operations. A contract-based approach is being used, which allows the specification of permitted compensations at runtime. We......Business to business integration has recently been performed by employing Web service environments. Moreover, such environments are being provided by major players on the technology markets. Those environments are based on open specifications for transaction coordination. When a failure...... in such an environment occurs, a compensation can be initiated to recover from the failure. However, current environments have only limited capabilities for compensations, and are usually based on backward recovery. In this paper, we introduce an engineering approach and an environment to deal with advanced...

  16. CHAMP climate data based on inversion of monthly average bending angles

    Directory of Open Access Journals (Sweden)

    J. Danzer

    2014-07-01

    Full Text Available GNSS Radio Occultation (RO refractivity climatologies for the stratosphere can be obtained from the Abel inversion of monthly average bending-angle profiles. The averaging of large numbers of profiles suppresses random noise and this, in combination with simple exponential extrapolation above an altitude of 80 km, circumvents the need for a "statistical optimization" step in the processing. Using data from the US-Taiwanese COSMIC mission, which provides ~ 1500–2000 occultations per day, it has been shown that this Average-Profile Inversion (API technique provides a robust method for generating stratospheric refractivity climatologies. Prior to the launch of COSMIC in mid-2006, the data records rely on data from the CHAMP mission. In order to exploit the full range of available RO data, the usage of CHAMP data is also required. CHAMP only provided ~ 200 profiles per day, and the measurements were noisier than COSMIC. As a consequence, the main research question in this study was to see if the average bending angle approach is also applicable to CHAMP data. Different methods for suppression of random noise – statistical and through data quality pre-screening – were tested. The API retrievals were compared with the more conventional approach of averaging individual refractivity profiles, produced with the implementation of statistical optimization used in the EUMETSAT Radio Occultation Meteorology Satellite Application Facility (ROM SAF operational processing. In this study it is demonstrated that the API retrieval technique works well for CHAMP data, enabling the generation of long-term stratospheric RO climate data records from August 2001 and onward. The resulting CHAMP refractivity climatologies are found to be practically identical to the standard retrieval at the DMI below altitudes of 35 km. Between 35 km to 50 km the differences between the two retrieval methods started to increase, showing largest differences at high latitudes and

  17. Image-based compensation for involuntary motion in weight-bearing C-arm cone-beam CT scanning of knees

    Science.gov (United States)

    Unberath, Mathias; Choi, Jang-Hwan; Berger, Martin; Maier, Andreas; Fahrig, Rebecca

    2015-03-01

    We previously introduced four fiducial marker-based strategies to compensate for involuntary knee-joint motion during weight-bearing C-arm CT scanning of the lower body. 2D methods showed significant reduction of motion- related artifacts, but 3D methods worked best. However, previous methods led to increased examination times and patient discomfort caused by the marker attachment process. Moreover, sub-optimal marker placement may lead to decreased marker detectability and therefore unstable motion estimates. In order to reduce overall patient discomfort, we developed a new image-based 2D projection shifting method. A C-arm cone-beam CT system was used to acquire projection images of five healthy volunteers at various flexion angles. Projection matrices for the horizontal scanning trajectory were calibrated using the Siemens standard PDS-2 phantom. The initial reconstruction was forward projected using maximum-intensity projections (MIP), yielding an estimate of a static scan. This estimate was then used to obtain the 2D projection shifts via registration. For the scan with the most motion, the proposed method reproduced the marker-based results with a mean error of 2.90 mm +/- 1.43 mm (compared to a mean error of 4.10 mm +/- 3.03 mm in the uncorrected case). Bone contour surrounding modeling clay layer was improved. The proposed method is a first step towards automatic image-based, marker-free motion-compensation.

  18. How a face may affect object-based attention: Evidence from adults and 8-month-old infants

    Directory of Open Access Journals (Sweden)

    Eloisa eValenza

    2014-03-01

    Full Text Available Object-based attention operates on perceptual objects, opening the possibility that the costs and benefits humans have to pay to move attention between objects might be affected by the nature of the stimuli. The current study reported two experiments with adults and 8-month-old infants investigating whether object-based-attention is affected by the stimulus social salience (faces vs. non-faces stimuli. Using the well-known cueing task developed by Egly et al. (1994 to study the object-based component of attention, in Experiment 1 adult participants were presented with two upright, inverted or scrambled faces and an eye-tracker measured their saccadic latencies to find a target that could appear on the same object that was just cued or on the other object that was uncued. Data showed that an object-based effect (a minor cost to shift attention within- compared to between-objects occurred only with scrambled face, but not with upright or inverted faces. In Experiment 2 the same task was performed with 8-month-old infants, using upright and inverted faces. Data revealed that an object-based effect only emerges for inverted faces but not for upright faces. Overall, these findings suggest that object-based attention is modulated by the stimulus social salience and by the experience acquired by the viewer with different objects.

  19. Drift-compensated Low-noise Frequency Synthesis Based on a cryoCSO for the KRISS-F1

    CERN Document Server

    Heo, Myoung-Sun; Lee, Won-Kyu; Lee, Sang-Bum; Hong, Hyun-Gue; Kwon, Taeg Yong; Park, Chang Yong; Yu, Dai-Hyuk; Santarelli, G; Hilton, Ashby; Luiten, Andre N; Hartnett, John G

    2016-01-01

    In this paper we report on the implementation and stability analysis of a drift-compensated frequency synthesizer from a cryogenic sapphire oscillator (CSO) designed for a Cs/Rb atomic fountain clock. The synthesizer has two microwave outputs of 7 GHz and 9 GHz for Rb and Cs atom interrogation, respectively. The short-term stability of these microwave signals, measured using an optical frequency comb locked to an ultra-stable laser, is better than $5\\times10^{-15}$ at an averaging time of 1 s. We demonstrate that the short-term stability of the synthesizer is lower than the quantum projection noise limit of the Cs fountain clock, KRISS-F1(Cs) by measuring the short-term stability of the fountain with varying trapped atom number. The stability of the fountain at 1-s averaging time reaches $2.5\\times10^{-14}$ at the highest atom number in the experiment when the synthesizer is used as an interrogation oscillator of the fountain. In order to compensate the frequency drift of the CSO, the output frequency of a wa...

  20. The impact of workers' compensation on outcomes of surgical and nonoperative therapy for patients with a lumbar disc herniation: SPORT.

    Science.gov (United States)

    Atlas, Steven J; Tosteson, Tor D; Blood, Emily A; Skinner, Jonathan S; Pransky, Glenn S; Weinstein, James N

    2010-01-01

    Prospective randomized and observational cohorts. To compare outcomes of patients with and without workers' compensation who had surgical and nonoperative treatment for a lumbar intervertebral disc herniation (IDH). Few studies have examined the association between worker's compensation and outcomes of surgical and nonoperative treatment. Patients with at least 6 weeks of sciatica and a lumbar IDH were enrolled in either a randomized trial or observational cohort at 13 US spine centers. Patients were categorized as workers' compensation or nonworkers' compensation based on baseline disability compensation and work status. Treatment was usual nonoperative care or surgical discectomy. Outcomes included pain, functional impairment, satisfaction and work/disability status at 6 weeks, 3, 6, 12, and 24 months. Combining randomized and observational cohorts, 113 patients with workers' compensation and 811 patients without were followed for 2 years. There were significant improvements in pain, function, and satisfaction with both surgical and nonoperative treatment in both groups. In the nonworkers' compensation group, there was a clinically and statistically significant advantage for surgery at 3 months that remained significant at 2 years. However, in the workers' compensation group, the benefit of surgery diminished with time; at 2 years no significant advantage was seen for surgery in any outcome (treatment difference for SF-36 bodily pain [-5.9; 95% CI: -16.7-4.9] and physical function [5.0; 95% CI: -4.9-15]). Surgical treatment was not associated with better work or disability outcomes in either group. Patients with a lumbar IDH improved substantially with both surgical and nonoperative treatment. However, there was no added benefit associated with surgical treatment for patients with workers' compensation at 2 years while those in the nonworkers' compensation group had significantly greater improvement with surgical treatment.

  1. The Effect of a Workplace-Based Early Intervention Program on Work-Related Musculoskeletal Compensation Outcomes at a Poultry Meat Processing Plant.

    Science.gov (United States)

    Donovan, Michael; Khan, Asaduzzaman; Johnston, Venerina

    2017-03-01

    Introduction The aim of this study is to determine whether a workplace-based early intervention injury prevention program reduces work-related musculoskeletal compensation outcomes in poultry meat processing workers. Methods A poultry meatworks in Queensland, Australia implemented an onsite early intervention which included immediate reporting and triage, reassurance, multidisciplinary participatory consultation, workplace modifica tion and onsite physiotherapy. Secondary pre-post analyses of the meatworks' compensation data over 4 years were performed, with the intervention commencing 2 years into the study period. Outcome measures included rate of claims, costs per claim and work days absent at an individual claim level. Where possible, similar analyses were performed on data for Queensland's poultry meat processing industry (excluding the meatworks used in this study). Results At the intervention meatworks, in the post intervention period an 18 % reduction in claims per 1 million working hours (p = 0.017) was observed. Generalized linear modelling revealed a significant reduction in average costs per claim of $831 (OR 0.74; 95 % CI 0.59-0.93; p = 0.009). Median days absent was reduced by 37 % (p = 0.024). For the poultry meat processing industry over the same period, generalized linear modelling revealed no significant change in average costs per claim (OR 1.02; 95 % CI 0.76-1.36; p = 0.91). Median days absent was unchanged (p = 0.93). Conclusion The introduction of an onsite, workplace-based early intervention injury prevention program demonstrated positive effects on compensation outcomes for work-related musculoskeletal disorders in poultry meat processing workers. Prospective studies are needed to confirm the findings of the present study.

  2. Psychology of Pay and Compensation

    NARCIS (Netherlands)

    Thierry, Hk.; Smelser, N.J.; Baltes, P.B.

    2002-01-01

    In most industrialized countries the compensation, of managers and employees is structured along quite comparable patterns. One part consists of base pay, a second part of results-oriented pay, and a third part of secondary labor conditions. In many instances part four is composed of perquisites:

  3. Heave Compensation System Based on Hybrid Fuzzy P+ID Control%基于混合模糊P+ID控制的升沉补偿系统

    Institute of Scientific and Technical Information of China (English)

    陈琦; 李伟; 王晓辉; 张奇峰; 张巍

    2016-01-01

    提出一种混合模糊P+ID控制算法,并将其应用于采用电控液压绞车的升沉补偿控制系统,使水下机器人在作业时不受母船升沉运动的影响。首先采用数字高通滤波器对惯性测量单元(IMU)获得的数据进行处理,计算出母船升沉运动的位移。然后推导出电控液压绞车系统的数学模型,并设计了基于混合模糊P+ID的升沉补偿控制器,根据母船升沉位移来控制液压绞车转动。最后通过仿真实验和物理平台实验验证证明了基于混合模糊P+ID的升沉补偿系统比常规PID系统有着更好的鲁棒性。%A hybrid fuzzy P+ID controller is proposed and applied to the heave compensation system using an electro-hydraulic winch system. The heave compensation system can decouple the operation of underwater vehicle from the motion of vessel. Firstly, the heave motion of vessel is calculated based on measurements from an inertial measurement unit (IMU) using a digital high-pass filter. Then, a mathematical model of the electro-hydraulic winch system is developed, and the heave compensation controller based on hybrid fuzzy P+ID controller is designed to control the winch rotation according to the vessel motion. Finally, simulation studies and real device experiments are conducted to demonstrate that the heave compensation systems based on the fuzzy P+ID controller is much more robust than the conventional PID controller.

  4. Workers’ Compensation Insurance and Occupational Injuries

    Directory of Open Access Journals (Sweden)

    Ilsoon Shin

    2011-06-01

    Conclusion: Private insurance system, fixed flat rate employers’ funding mechanism, and higher coverage of compensation scheme are significantly and positively correlated with lower level of occupational accidents compared with the public insurance system, risk-based funding system, and lower coverage of compensation scheme.

  5. β2-microglobulin Normalization Within 6 months of Ibrutinib-based Treatment is Associated with Superior PFS in CLL

    Science.gov (United States)

    Thompson, Philip A.; O’Brien, Susan M.; Xiao, Lianchun; Wang, Xuemei; Burger, Jan A.; Jain, Nitin; Ferrajoli, Alessandra; Estrov, Zeev; Keating, Michael J.; Wierda, William G.

    2016-01-01

    High pre-treatment β2-microglobulin (B2M) level is associated with inferior survival outcomes. However, the prognostic and predictive significance of changes in B2M during treatment have not been reported. We analyzed 83 patients treated with ibrutinib-based regimens (66 relapsed/refractory) and 198 treatment-naïve (TN) patients treated with combined fludarabine, cyclophosphamide and rituximab (FCR) to characterize change in B2M and their relationship to clinical outcomes. B2M rapidly fell during treatment with ibrutinib; in multivariable analysis (MVA), patients who received FCR [OR 0.40 (0.18–0.90), p=0.027] were less likely to normalize B2M at 6 months than patients treated with ibrutinib. On univariable analysis, normalization of B2M was associated with superior progression-free survival (PFS) from the 6-month landmark in patients treated with ibrutinib-based regimens and FCR. On MVA, failure to normalize B2M at 6 months of treatment was associated with inferior PFS [HR 16.9 (1.3–220.0), p=0.031] for ibrutinib-treated patients, after adjusting for the effects of baseline B2M, stage, fludarabine-refractory disease and del(17p). In contrast, in FCR-treated patients, bone marrow MRD-negative status was the only variable significantly associated with superior PFS [HR 0.28 (0.12–0.67), p=0.004]. Normalization of B2M at 6 months in ibrutinib-treated patients thus was a useful predictor of subsequent PFS and may assist clinical decision-making. PMID:26588193

  6. A national evaluation of community-based youth cessation programs: end of program and twelve-month outcomes.

    Science.gov (United States)

    Curry, Susan J; Mermelstein, Robin J; Emery, Sherry L; Sporer, Amy K; Berbaum, Michael L; Campbell, Richard T; Flay, Brian; Warnecke, Richard B

    2013-03-01

    Most youth cessation treatment research consists of efficacy studies in which treatments are evaluated under optimal conditions of delivery. Less is known about the effectiveness of youth cessation treatments delivered in real-world, community based settings. A national sample of 41 community-based youth cessation programs participated in a longitudinal evaluation to identify site, program, and participant characteristics associated with successful cessation. Validated quit rates were comparable to those in randomized controlled trials; 7-day abstinence at the end of program averaged 14% and 30-day abstinence at 12 months averaged 12%. Multivariate GEE models explored predictors of smoking cessation at the end of the programs and at 12 months. Results showed correlates of both short- and long-term cessation. Findings point to the importance of both individual and community-level variables, including motivation, opportunities for and encouragement to engage in activities outside of academics, having youth participate in treatment before they become highly dependent smokers, and community norms and ordinances that discourage youth purchase, use and possession of tobacco. Providing evidence-based treatment to youth in community-based settings results in successful cessation.

  7. Monthly oceanic rainfall based on METH techniques: DMSP SSM/I V6 and SSMIS continuity

    Science.gov (United States)

    Chiu, L. S.; Gao, S.; Shin, D.-B.; Cho, Y.-J.; Adler, R. F.; Huffman, G.; Bolvin, D.; Nelkin, E.

    2012-04-01

    As part of the Global Precipitation Climatology Project (GPCP), our group have been producing oceanic rainfall over 2.5 and 5 degree boxes by applying the Microwave Emission brightness Temperature (Tb) Histogram, or METH technique to the Special Sensor Microwave Imager (SSM/I) data taken on board the Defense Meteorological Satellite Program (DMSP) satellite series. Recently, the rainfall series have been updated using the V6 SSM/I provided by RSS (Chiu and Chokngamwong., 2010). With the demise of the F15 SSM/I sensor, we examine the use of the SSMIS series to continue the DMSP time series. With its long duration, the DMSP satellite sensors constitute a unique data set capable of producing microwave-based products for climate studies. We compared the F13 SSM/I and F17 SSMIS for the period January 2008 - September 2009. The METH technique matches the histogram of Tb (twice 19V minus 22V) to a mixed-distribution of rain rates and estimates the parameters of the rain rate distribution. Mathematical convergence of the matching procedure is reached when a certain Chi-square threshold is reached. The important parameters are the Tb of the non-raining pixels (To) and the freezing level (FL) of the grid box considered. The sample size of the SSMIS is much larger than the SSM/I, hence the convergence criteria is relaxed by changing the Chi-square threshold. Preliminary results show a slight shift of the To (~0.8K). By adjusting To by a constant, the domain average SSMIS rain rates and FL are computed to within 2% and 1% of the SSM/I rain rates, respectively. Further investigation of the SSMIS METH rain rate will involve the comparison of the 19V and 22V and fine tuning the Chi-square parameter.

  8. H{infinity} Filtering for Dynamic Compensation of Self-Powered Neutron Detectors - A Linear Matrix Inequality Based Method -

    Energy Technology Data Exchange (ETDEWEB)

    Park, M.G.; Kim, Y.H.; Cha, K.H.; Kim, M.K. [Korea Electric Power Research Institute, Taejon (Korea)

    1999-07-01

    A method is described to develop and H{infinity} filtering method for the dynamic compensation of self-powered neutron detectors normally used for fixed incore instruments. An H{infinity} norm of the filter transfer matrix is used as the optimization criteria in the worst-case estimation error sense. Filter modeling is performed for both continuous- and discrete-time models. The filter gains are optimized in the sense of noise attenuation level of H{infinity} setting. By introducing Bounded Real Lemma, the conventional algebraic Riccati inequalities are converted into Linear Matrix Inequalities (LMIs). Finally, the filter design problem is solved via the convex optimization framework using LMIs. The simulation results show that remarkable improvements are achieved in view of the filter response time and the filter design efficiency. (author). 15 refs., 4 figs., 3 tabs.

  9. Modeling the extrinsic incubation of Dirofilaria immitis in South America based on monthly and continuous climatic data.

    Science.gov (United States)

    Cuervo, Pablo F; Rinaldi, Laura; Cringoli, Giuseppe

    2015-04-15

    The spread and recrudescence of dirofilariosis across several regions, either caused by Dirofilaria immitis or D. repens, responds to many factors. Building upon the temperature model by Slocombe et al. (1989), a number of studies have been performed to generate predictive models for dirofilariosis. These studies have demonstrated the length of transmission periods and the number of Dirofilaria generations supported throughout several regions of the world (either at large or at small-scale). The usual procedure have proved to be extremely time consuming, as it appears impractical when assessing potential transmission at large scale, such as at a country or large-scale level. Due to the increasing need to suggest standardized surveillance protocols and apply adequate preventive measures at national and regional levels, a model for calculation of Dirofilaria HDUs based on monthly data was adapted for large-scale regional use. The models proposed are based on both point data (meteorological stations) and interpolated climate data layers (WorldClim). Three different models (daily and monthly models based on point data, and monthly model based on continuous data) were developed and compared statistically. When compared with the results from the classical daily model, the monthly models proposed accurately predicted the locations were extrinsic incubation was possible. These models proved to be adequate for the regional analysis of the extrinsic incubation of D. immitis and, hence, the relative risk of transmission in South America. Further, these models confirm that favorable temperatures for heartworm transmission in South America are present in most of the countries. D. immitis extrinsic incubation follows a seasonal pattern in Argentina, Chile, Uruguay, eastern Paraguay and southeastern Brazil; while in northern half of South America (less than 25° S) transmission may occur year-round. Moreover, high risk areas suitable for dirofilariasis transmission are not

  10. Comparison of frequency-distance relationship and Gaussian-diffusion-based methods of compensation for distance-dependent spatial resolution in SPECT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kohli, Vandana [Department of Nuclear Medicine, The University of Massachusetts Medical Center, 55 Lake Ave North, Worcester, MA 01655 (United States); Department of Electrical Engineering, The University of Massachusetts Lowell, 1 University Ave, Lowell, MA 01854 (United States); King, Micgael A.; Glick, Stephen J. [Department of Nuclear Medicine, The University of Massachusetts Medical Center, 55 Lake Ave North, Worcester, MA 01655 (United States); Pan, Tin-Su [The Applied Science Laboratory, General Electric Company, Milwaukee, WI 53201 (United States)

    1998-04-01

    The goal of this investigation was to compare resolution recovery versus noise level of two methods for compensation of distance-dependent resolution (DDR) in SPECT imaging. The two methods of compensation were restoration filtering based on the frequency-distance relationship (FDR) prior to iterative reconstruction, and modelling DDR in the projector/backprojector pair employed in iterative reconstruction. FDR restoration filtering was computationally faster than modelling the detector response in iterative reconstruction. Using Gaussian diffusion to model the detector response in iterative reconstruction sped up the process by a factor of 2.5 over frequency domain filtering in the projector/backprojector pair. Gaussian diffusion modelling resulted in a better resolution versus noise tradeoff than either FDR restoration filtering or solely modelling attenuation in the projector/backprojector pair of iterative reconstruction. For the pixel size investigated herein (0.317 cm), accounting for DDR in the projector/backprojector pair by Gaussian diffusion, or by applying a blurring function based on the distance from the face of the collimator at each distance, resulted in very similar resolution recovery and slice noise level. (author)

  11. Lipid based nutrient supplements (LNS) for treatment of children (6 months to 59 months) with moderate acute malnutrition (MAM): A systematic review

    Science.gov (United States)

    Pena-Rosas, Juan Pablo; Boy-Mena, Evelyn; Sachdev, Harshpal S.

    2017-01-01

    Background Moderate acute malnutrition is a major public health problem affecting children from low- and middle-income countries. Lipid nutrient supplements have been proposed as a nutritional intervention for its treatment. Objectives To evaluate the effectiveness and safety of LNS for the treatment of MAM in infants and children 6 to 59 months of age. Study design Systematic review of randomized-controlled trials and controlled before-after studies. Results Data from nine trials showed that use of LNS, in comparison to specially formulated foods, improved the recovery rate (RR 1.08; 95% CI 1.02–1.14, 8 RCTs, 8934 participants, low quality evidence); decreased the chances of no recovery (RR 0.70; 95% CI 0.58–0.85, 7 RCTs, 8364 participants, low quality evidence) and the risk of deterioration into severe acute malnutrition (RR 0.87; 95% CI 0.73–1.03, 6 RCTs, 6788 participants, low quality evidence). There was little impact on mortality (RR 0.94, 95% CI 0.54–1.52, 8 RCTs, 8364 participants, very-low- quality evidence) or default rate (RR 1.32; 95% CI 0.73–2.4, 7 studies, 7570 participants, low quality evidence). There was improvement in weight gain, weight-for-height z-scores, height-for-age z-scores and mid-upper arm circumference. Subset analyses suggested higher recovery rates with greater amount of calories provided and with ready-to-use therapeutic foods, in comparison to ready-to-use supplementary foods. One study comparing LNS with nutritional counselling (very low quality evidence) showed higher chance of recovery, lower risk of deteriorating into severe acute malnutrition and lower default rate, with no impact on mortality, and no recovery. Conclusions Evidence restricted to the African regions suggests that LNS may be slightly more effective than specially formulated fortified foods or nutritional counselling in recovery from MAM, lowering the risk of deterioration into SAM, and improving weight gain with little impact on mortality or default

  12. 基于阵列技术的MEMS陀螺温度补偿方法%An Array Technique Based Method for Temperature Compensation of MEMS Gyroscopes

    Institute of Scientific and Technical Information of China (English)

    沈强; 刘洁瑜

    2015-01-01

    为了减少温度对MEMS陀螺测量精度的影响,提出了一种采用阵列技术的MEMS陀螺仪温度误差补偿新方法。该方法不需要进行温度测量,通过对多陀螺输出进行数据融合以消除温度对陀螺仪输出的影响,达到正确检测角速率的目的,简化了系统结构。采用遗传算法优化的BP神经网络来进行陀螺阵列数据的融合,抛开通常把零偏和标度因数分开建模补偿的思想,将两者统一进行补偿。实验结果表明,该方法能够大幅度降低温度造成的陀螺误差,从而满足工程应用需要。%In order to decrease temperature related errors in MEMS gyroscope, a novel method based on array technique is proposed for temperature compensation of the gyroscope. The advantage of this method is that it is not need to measure the temperature, in stead, data fusion of the output of several gyroscopes is used to reduce the influence of temperature, and the system structure is simplified. The BP neural network optimized by genetic algorithms is used in data fusion of the gyroscope data, which compensates the error of the output of gyroscopes directly, while the zero bias and scale factors are compensated separately in general. The results of the experiments show that the method proposed can significantly reduce the error of gyroscope caused by temperature, and thus can improve the accuracy.

  13. Research on the Willingness to Accept Compensation and Compensation Sharing of Returning Land for Farming to Forestry in Zhangjiakou and Chengde Region

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to study the willingness to accept compensation and compensation sharing of returning land for farming to forestry in Zhangjiakou and Chengde region.[Method] Based on the investigation of farmers' willingness to accept ecological compensation in Zhangjiakou and Chengde region,farmers' willingness to accept compensation was quantized,and the calculation model of sharing rate of ecological compensation was established,finally the sharing rate of ecological compensation was calculated c...

  14. Six-month evaluation of a resin/dentin interface created by methacrylate and silorane-based materials

    Directory of Open Access Journals (Sweden)

    Renata Kirita Doi SAMPAIO

    2013-01-01

    Full Text Available Objectives This study aimed to compare the micro-tensile bond strength of methacrylate resin systems to a silorane-based restorative system on dentin after 24 hours and six months water storage. Material and Methods The restorative systems Adper Single Bond 2/Filtek Z350 (ASB, Clearfil SE Bond/Z350 (CF, Adper SE Plus/Z350 (ASEP and P90 Adhesive System/Filtek P90 (P90 were applied on flat dentin surfaces of 20 third molars (n=5. The restored teeth were sectioned perpendicularly to the bonding interface to obtain sticks (0.8 mm2 to be tested after 24 hours (24 h and 6 months (6 m of water storage, in a universal testing machine at 0.5 mm/min. The data was analyzed via two-way Analysis of Variance/Bonferroni post hoc tests at 5% global significance. Results Overall outcomes did not indicate a statistical difference for the resin systems (p=0.26 nor time (p=0.62. No interaction between material × time was detected (p=0.28. Mean standard-deviation in MPa at 24 h and 6 m were: ASB 31.38 (4.53 and 30.06 (1.95, CF 34.26 (3.47 and 32.75 (4.18, ASEP 29.54 (4.14 and 33.47 (2.47, P90 30.27 (2.03 and 31.34 (2.19. Conclusions The silorane-based system showed a similar performance to methacrylate-based materials on dentin. All systems were stable in terms of bond strength up to 6 month of water storage.

  15. Determinants of Successful Weight Loss After Using a Commercial Web-Based Weight Reduction Program for Six Months: Cohort Study

    Science.gov (United States)

    Postrach, Elisa; Aspalter, Rosa; Elbelt, Ulf; Koller, Michael; Longin, Rita; Schulzke, Jörg-Dieter

    2013-01-01

    Background The Internet is widely available and commonly used for health information; therefore, Web-based weight loss programs could provide support to large parts of the population in self-guided weight loss. Previous studies showed that Web-based weight loss interventions can be effective, depending on the quality of the program. The most effective program tools are visual progress charts or tools for the self-monitoring of weight, diet, and exercises. KiloCoach, a commercial program currently available in German-speaking countries, incorporates these features. A previous investigation showed that the program effectively supports users in losing weight. Objective We investigated weight loss dynamics stratified by weight loss success after 6-month use of KiloCoach. Furthermore, we analyzed possible associations between intensity of program use and weight loss. The results are intended for tailoring user recommendations for weight-loss Internet platforms. Methods Datasets of KiloCoach users (January 1, 2008 to December 31, 2011) who actively used the platform for 6 months or more were assigned to this retrospective analysis. Users (N=479) were 42.2% men, mean age of 44.0 years (SD 11.7), with a mean body mass index (BMI) of 31.7 kg/m2 (SD 3.2). Based on the weight loss achieved after 6 months, 3 success groups were generated. The unsuccessful group lost weight. At baseline, the unsuccessful (n=261, 54.5%), moderate success (n=133, 27.8%), and high success (n=85, 17.8%) groups were similar in age, weight, BMI, and gender distribution. Results After 6 months, the unsuccessful group lost 1.2% (SD 2.4), the moderate success group lost 7.4% (SD 1.5), and the high success group lost 14.2% (SD 3.8) of their initial weight (Pweight loss (weeks 3-4), the total number of dietary protocols, and the total number of weight entries were independent predictors for 6-month weight reduction (all Pweight reduction. Sensitivity analysis by baseline carried forward method confirmed

  16. 38 CFR 21.3023 - Nonduplication; pension, compensation, and dependency and indemnity compensation.

    Science.gov (United States)

    2010-07-01

    ... parents. Where, however, entitlement is based on the death of more than one parent in the same parental... before attaining age 18 or while helpless based on the service of another parent in the same parental... concurrently with pension, compensation or dependency and indemnity compensation. (Authority: 38 U.S.C....

  17. Compensation issues tough to navigate

    Energy Technology Data Exchange (ETDEWEB)

    Madison, Alison L.

    2012-02-12

    Monthly economic diversity column for the Tri-City Herald - excerpt pasted below: Most industries out there are feeling the shift to a more educated, thus more empowered consumer. The legal field is no exception, which is why it's no surprise that lawsuits are on the rise. Today's society is one in which people are more aware than ever of their rights, and often equally convinced of their entitlements in a number of areas. For business owners, employees represent a major source of potential lawsuits. And compensation is an area of particular concern given that many complaints against employers revolve around it in some way.

  18. PRESSURE COMPENSATION METHOD OF UNDERWATER HYDRAULIC SYSTEM WITH HYDRAULIC POWER UNIT BEING UNDER ATMOSPHERIC CIRCUMSTANCE AND PRESSURE COMPENSATED VALVE

    Institute of Scientific and Technical Information of China (English)

    Wang Qingfeng; Li Yanmin; Zhong Tianyu; Xu Guohua

    2005-01-01

    Based on the analysis of the-state-of-the-art of pressure compensation of underwater hydraulic systems (UHSs), a new method of pressure compensation of UHSs, whose hydraulic power unit is in the atmospheric circumstance, is proposed. And a pilot-operated relief valve with pressure compensation is realized. The pressure compensation precision is guaranteed by direct detection. Its dynamic performance and stability are improved by a dynamic feedback. Theoretical study, simulation and experiment show that the pilot-operated relief valve with pressure compensation has a fine property of tracking underwater ambient pressure and meet the requirement of underwater ambient pressure compensation.

  19. Options in Compensation

    DEFF Research Database (Denmark)

    Flor, Christian Riis; Frimor, Hans; Munk, Claus

    2014-01-01

    We derive the optimal compensation contract in a principal–agent setting in which outcome is used to provide incentives for both effort and risky investments. To motivate investment, optimal compensation entails rewards for high as well as low outcomes, and it is increasing at the mean outcome to...

  20. Cooperation, compensation and transition

    NARCIS (Netherlands)

    Ju, Y.

    2004-01-01

    Cooperation and compensation are two important and well-linked issues in economics. The central question in cooperation is how to share the joint gains among participating players. Compensation is a specific aspect of surplus sharing problems providing incentives for agents to sacrifice their own di

  1. Indexing Executive Compensation Contracts

    NARCIS (Netherlands)

    I. Dittmann (Ingolf); E.G. Maug (Ernst); O.G. Spalt (Oliver)

    2013-01-01

    textabstractWe analyze the efficiency of indexing executive pay by calibrating the standard model of executive compensation to a large sample of US CEOs. The benefits from linking the strike price of stock options to an index are small and fully indexing all options would increase compensation costs

  2. Decentralized adaptive robust control based on sliding mode and nonlinear compensator for the control of ankle movement using functional electrical stimulation of agonist-antagonist muscles

    Science.gov (United States)

    Kobravi, Hamid-Reza; Erfanian, Abbas

    2009-08-01

    A decentralized control methodology is designed for the control of ankle dorsiflexion and plantarflexion in paraplegic subjects with electrical stimulation of tibialis anterior and calf muscles. Each muscle joint is considered as a subsystem and individual controllers are designed for each subsystem. Each controller operates solely on its associated subsystem, with no exchange of information between the subsystems. The interactions between the subsystems are taken as external disturbances for each isolated subsystem. In order to achieve robustness with respect to external disturbances, unmodeled dynamics, model uncertainty and time-varying properties of muscle-joint dynamics, a robust control framework is proposed which is based on the synergistic combination of an adaptive nonlinear compensator with a sliding mode control and is referred to as an adaptive robust control. Extensive simulations and experiments on healthy and paraplegic subjects were performed to demonstrate the robustness against the time-varying properties of muscle-joint dynamics, day-to-day variations, subject-to-subject variations, fast convergence, stability and tracking accuracy of the proposed method. The results indicate that the decentralized robust control provides excellent tracking control for different reference trajectories and can generate control signals to compensate the muscle fatigue and reject the external disturbance. Moreover, the controller is able to automatically regulate the interaction between agonist and antagonist muscles under different conditions of operating without any preprogrammed antagonist activities.

  3. Hysteresis compensation of the piezoelectric ceramic actuators-based tip/tilt mirror with a neural network method in adaptive optics

    Science.gov (United States)

    Wang, Chongchong; Wang, Yukun; Hu, Lifa; Wang, Shaoxin; Cao, Zhaoliang; Mu, Quanquan; Li, Dayu; Yang, Chengliang; Xuan, Li

    2016-05-01

    The intrinsic hysteresis nonlinearity of the piezo-actuators can severely degrade the positioning accuracy of a tip-tilt mirror (TTM) in an adaptive optics system. This paper focuses on compensating this hysteresis nonlinearity by feed-forward linearization with an inverse hysteresis model. This inverse hysteresis model is based on the classical Presiach model, and the neural network (NN) is used to describe the hysteresis loop. In order to apply it in the real-time adaptive correction, an analytical nonlinear function derived from the NN is introduced to compute the inverse hysteresis model output instead of the time-consuming NN simulation process. Experimental results show that the proposed method effectively linearized the TTM behavior with the static hysteresis nonlinearity of TTM reducing from 15.6% to 1.4%. In addition, the tip-tilt tracking experiments using the integrator with and without hysteresis compensation are conducted. The wavefront tip-tilt aberration rejection ability of the TTM control system is significantly improved with the -3 dB error rejection bandwidth increasing from 46 to 62 Hz.

  4. 基于Dynaform的回弹补偿算法与系统%The Compensation Algorithm and System for Springback in Sheet Metal Forming Based on Dynain File

    Institute of Scientific and Technical Information of China (English)

    胡志超; 李延平; 常勇; 王沁峰; 李毅

    2012-01-01

    By analyzing the format of Dynain file, an algorithm was developed for compensating springback in sheet metal forming based on theories of linear control system, Fourier transform, transfer function and the Dynain file from the forming and springback numerical simulated result of Dynaform. In terms of this algorithm, the springbackcom system was designed by calling functions from OpenGL graphic library and Matlab Matrix operation tools through Visual C ++6.0. The developed system was conducive for spring back error analysis and springback compensation.%以线性控制系统、傅里叶变换及传递函数为基本理论,在分析Dynain文件格式基础上,提出了一种基于Dynaform软件冲压回弹结果Dynain文件的回弹补偿算法.基于该算法,以Visual C++6.0为平台、以Matlab为矩阵运算工具、以OpenGL为图形开发工具,开发了基于Dynain文件的回弹补偿系统springbackcom.该系统为回弹误差分析及回弹补偿提供了有力的支持.

  5. Influence of neighbourhood purchasing power on breastfeeding at four months of age: a Swedish population-based cohort study.

    Science.gov (United States)

    Almquist-Tangen, Gerd; Strömberg, Ulf; Holmén, Anders; Alm, Bernt; Roswall, Josefine; Bergman, Stefan; Dahlgren, Jovanna

    2013-11-15

    Parental socioeconomic status (SES) is an important determinant in child health, influencing beneficial factors such as breastfeeding. A better understanding of the influence of neighbourhood-level SES measures, relating to spatial determinants, might lead to targeted actions to promote breastfeeding during infancy. A cross-sectional study analysis the association between breastfeeding at four months of age and neighbourhood purchasing power, taking account of individual-level variables including maternal age, smoking and parental level of education. Data were obtained from a prospective population- based cohort study recruited from birth in 2007-2008 in the Halland region, southwestern Sweden. Questionnaire data on the individual-level variables and the outcome variable of breastfeeding at four months (yes/no) were used (n=2,407). Each mother was geo-coded with respect to her residential parish (there are 61 parishes in the region) and then stratified by parish-level household purchasing power. It emerged that four neighbourhood characteristics were reasonable to use, viz. purchasing power. The proportion of mothers not breastfeeding at four months of age showed a highly significant trend across the neighbourhood strata (p=0.00004): from 16.3% (purchasing power) to 29.4% (≥ 30% with low purchasing power), yielding an OR of 2.24 (95% confidence interval: 1.45-3.16). After adjusting for the individual-level variables, the corresponding OR=1.63 (1.07-2.56) was significant and the trend across the strata was still evident (p=0.05). A multi-level analysis estimated that, in the neighbourhoods with ≥ 30% of the families with low purchasing power, 20% more mothers than expected, taking account of the individual-level factors, reported no breastfeeding at four months of age (≥ 95% posterior probability of an elevated observed-to-expected ratio). The neighbourhood purchasing power provided a spatial determinant of low numbers of mothers breastfeeding at four months

  6. Fundamental statistical relationships between monthly and daily meteorological variables: Temporal downscaling of weather based on a global observational dataset

    Science.gov (United States)

    Sommer, Philipp; Kaplan, Jed

    2016-04-01

    Accurate modelling of large-scale vegetation dynamics, hydrology, and other environmental processes requires meteorological forcing on daily timescales. While meteorological data with high temporal resolution is becoming increasingly available, simulations for the future or distant past are limited by lack of data and poor performance of climate models, e.g., in simulating daily precipitation. To overcome these limitations, we may temporally downscale monthly summary data to a daily time step using a weather generator. Parameterization of such statistical models has traditionally been based on a limited number of observations. Recent developments in the archiving, distribution, and analysis of "big data" datasets provide new opportunities for the parameterization of a temporal downscaling model that is applicable over a wide range of climates. Here we parameterize a WGEN-type weather generator using more than 50 million individual daily meteorological observations, from over 10'000 stations covering all continents, based on the Global Historical Climatology Network (GHCN) and Synoptic Cloud Reports (EECRA) databases. Using the resulting "universal" parameterization and driven by monthly summaries, we downscale mean temperature (minimum and maximum), cloud cover, and total precipitation, to daily estimates. We apply a hybrid gamma-generalized Pareto distribution to calculate daily precipitation amounts, which overcomes much of the inability of earlier weather generators to simulate high amounts of daily precipitation. Our globally parameterized weather generator has numerous applications, including vegetation and crop modelling for paleoenvironmental studies.

  7. A Power Compensated Novel Architecture of RM-OXC Based on T-FBG and OC: A High-speed and Cost-effective System

    Science.gov (United States)

    Singh, Manpreet; Dewra, Sanjeev

    2017-05-01

    This paper presents a high-speed, power-compensated novel architecture of N×N reconfigurable multiwavelength optical cross connect (RM-OXC) based on tunable fiber Bragg grating (T-FBG) and optical circulator (OC). FBG and OC-based OXCs are network elements that play a significant role in optical networks to offer more network survivability and reconfiguration flexibility. Optical signal-to-noise ratio of 71.05, 69.05 and 67.05 dB is achieved with acceptable quality factor of 7.54, 6.95 and 6.41, respectively, with 10 Gbps having input transmission power of -8 dBm at different transmission distances (40, 50, 60 km). It is found that the signal is communicated to a maximum distance of 60 km in the presence of fiber nonlinearities without optical amplifier at 0.8-nm channel spacing.

  8. Compensation of negative sequence stator flux of doubly-fed induction generator using polar voltage control-based direct torque control under unbalanced grid voltage condition

    Directory of Open Access Journals (Sweden)

    Badrinarayan Bansilal Pimple

    2015-02-01

    Full Text Available This study proposes a polar voltage control-based direct torque control method to reduce the effects of unbalanced grid voltage on doubly-fed induction generator (DFIG-based wind turbine system. Under unbalanced grid voltage, the stator flux has a negative sequence component which leads to second harmonic pulsation in torque, stator active power, stator reactive power, stator current and rotor current. In the control scheme, the negative sequence rotor voltage vector is controlled to compensate the negative sequence stator flux by negative sequence rotor flux. Simulation study is carried out on a 2 MW DFIG system using MATLAB/SIMULINK. Feasibility of the proposed control strategy is experimentally verified on a 1.5 kW DFIG system.

  9. A new model based on adaptation of the external loop to compensate the hysteresis of tactile sensors.

    Science.gov (United States)

    Sánchez-Durán, José A; Vidal-Verdú, Fernando; Oballe-Peinado, Óscar; Castellanos-Ramos, Julián; Hidalgo-López, José A

    2015-10-15

    This paper presents a novel method to compensate for hysteresis nonlinearities observed in the response of a tactile sensor. The External Loop Adaptation Method (ELAM) performs a piecewise linear mapping of the experimentally measured external curves of the hysteresis loop to obtain all possible internal cycles. The optimal division of the input interval where the curve is approximated is provided by the error minimization algorithm. This process is carried out off line and provides parameters to compute the split point in real time. A different linear transformation is then performed at the left and right of this point and a more precise fitting is achieved. The models obtained with the ELAM method are compared with those obtained from three other approaches. The results show that the ELAM method achieves a more accurate fitting. Moreover, the involved mathematical operations are simpler and therefore easier to implement in devices such as Field Programmable Gate Array (FPGAs) for real time applications. Furthermore, the method needs to identify fewer parameters and requires no previous selection process of operators or functions. Finally, the method can be applied to other sensors or actuators with complex hysteresis loop shapes.

  10. Wind and Wave Disturbances Compensation to Floating Offshore Wind Turbine Using Improved Individual Pitch Control Based on Fuzzy Control Strategy

    Directory of Open Access Journals (Sweden)

    Feng Yang

    2014-01-01

    Full Text Available Due to the rich and high quality of offshore wind resources, floating offshore wind turbine (FOWT arouses the attentions of many researchers. But on a floating platform, the wave and wind induced loads can significantly affect power regulation and vibration of the structure. Therefore, reducing these loads becomes a challenging part of the design of the floating system. To better alleviate these fatigue loads, a control system making compensations to these disturbances is proposed. In this paper an individual pitch control (IPC system integrated with disturbance accommodating control (DAC and model prediction control (MPC through fuzzy control is developed to alleviate the fatigue loads. DAC is mainly used to mitigate the effects of wind disturbance and MPC counteracts the effects of wave on the structure. The new individual pitch controller is tested on the NREL offshore 5 MW wind turbine mounted on a barge with a spread-mooring system, running in FAST, operating above-rated condition. Compared to the original baseline collective pitch control (CPC (Jonkman et al., 2007, the IPC system shows a better performance in reducing fatigue loads and is robust to complex wind and wave disturbances as well.

  11. A Data Dropout Compensation Algorithm Based on the Iterative Learning Control Methodology for Discrete-Time Systems

    Directory of Open Access Journals (Sweden)

    S. Alonso-Quesada

    2015-01-01

    Full Text Available This paper deals with the convergence of a remote iterative learning control system subject to data dropouts. The system is composed by a set of discrete-time multiple input-multiple output linear models, each one with its corresponding actuator device and its sensor. Each actuator applies the input signals vector to its corresponding model at the sampling instants and the sensor measures the output signals vector. The iterative learning law is processed in a controller located far away of the models so the control signals vector has to be transmitted from the controller to the actuators through transmission channels. Such a law uses the measurements of each model to generate the input vector to be applied to its subsequent model so the measurements of the models have to be transmitted from the sensors to the controller. All transmissions are subject to failures which are described as a binary sequence taking value 1 or 0. A compensation dropout technique is used to replace the lost data in the transmission processes. The convergence to zero of the errors between the output signals vector and a reference one is achieved as the number of models tends to infinity.

  12. A New Model Based on Adaptation of the External Loop to Compensate the Hysteresis of Tactile Sensors

    Directory of Open Access Journals (Sweden)

    José A. Sánchez-Durán

    2015-10-01

    Full Text Available This paper presents a novel method to compensate for hysteresis nonlinearities observed in the response of a tactile sensor. The External Loop Adaptation Method (ELAM performs a piecewise linear mapping of the experimentally measured external curves of the hysteresis loop to obtain all possible internal cycles. The optimal division of the input interval where the curve is approximated is provided by the error minimization algorithm. This process is carried out off line and provides parameters to compute the split point in real time. A different linear transformation is then performed at the left and right of this point and a more precise fitting is achieved. The models obtained with the ELAM method are compared with those obtained from three other approaches. The results show that the ELAM method achieves a more accurate fitting. Moreover, the involved mathematical operations are simpler and therefore easier to implement in devices such as Field Programmable Gate Array (FPGAs for real time applications. Furthermore, the method needs to identify fewer parameters and requires no previous selection process of operators or functions. Finally, the method can be applied to other sensors or actuators with complex hysteresis loop shapes.

  13. 基于Buck交-交斩波器的无功补偿器拓扑与控制方法设计%Topology and Control Strategy Design for Buck AC-AC Chopper Based Var Compensators

    Institute of Scientific and Technical Information of China (English)

    武伟; 谢少军; 汤雨; 许津铭

    2013-01-01

    首先介绍了一种新的交流斩波型无功补偿器,无需直流储能环节,系统可靠性得到加强.以Buck型交流斩波无功补偿器为对象,分析了交流斩波无功补偿的基本原理和补偿特性,推导出占空比与补偿电流之间的关系,建立了系统分析模型.在此基础上,提出了基于广义积分的直接电流控制策略,并给出了参数设计准则,最后进行了仿真和实验验证.仿真和实验结果表明,基于直接电流控制的Buck型交流斩波无功补偿器可以实现对网侧无功功率的实时补偿.%A new AC-AC chopper based var compensator is proposed. It does not require the DC-link energy storage and can effectively enhance the system reliability. The basic principles and compensation characteristics of the Buck AC/AC chopper based var compensator are described, the relationship between duty ratio and compensation current is derived, and the system analysis model is developed. A new direct current control method based on the second order generalized integral is proposed for the var compensator with detailed design criteria as well. The experimental and simulation results demonstrate that the realtime compensation of reactive power in grid side can be realized by this var compensator based on a direct current controlled Buck AC/AC chopper.

  14. Approximation of the optimal compensator for a large space structure

    Science.gov (United States)

    Mackay, M. K.

    1983-01-01

    This paper considers the approximation of the optimal compensator for a Large Space Structure. The compensator is based upon a solution to the Linear Stochastic Quadratic Regulator problem. Colocation of sensors and actuators is assumed. A small gain analytical solution for the optimal compensator is obtained for a single input/single output system, i.e., certain terms in the compensator can be neglected for sufficiently small gain. The compensator is calculated in terms of the kernel to a Volterra integral operator using a Neumann series. The calculation of the compensator is based upon the C sub 0 semigroup for the infinite dimensional system. A finite dimensional approximation of the compensator is, therefore, obtained through analysis of the infinite dimensional compensator which is a compact operator.

  15. Approximation of the optimal compensator for a large space structure

    Science.gov (United States)

    Mackay, M. K.

    1983-01-01

    This paper considers the approximation of the optimal compensator for a Large Space Structure. The compensator is based upon a solution to the Linear Stochastic Quadratic Regulator problem. Colocation of sensors and actuators is assumed. A small gain analytical solution for the optimal compensator is obtained for a single input/single output system, i.e., certain terms in the compensator can be neglected for sufficiently small gain. The compensator is calculated in terms of the kernel to a Volterra integral operator using a Neumann series. The calculation of the compensator is based upon the C sub 0 semigroup for the infinite dimensional system. A finite dimensional approximation of the compensator is, therefore, obtained through analysis of the infinite dimensional compensator which is a compact operator.

  16. Working conditions, compensation and absenteeism.

    Science.gov (United States)

    Ose, Solveig Osborg

    2005-01-01

    This paper examines absence behaviour in relation to the working environment. A theoretical model is built in order to separate the effects of voluntary absences and absences related to ill health, where health effects are assumed to be tied to working conditions. This model is based on the Shapiro and Stiglitz efficiency wage model. In addition, work environment is introduced as a part of the compensation package. The model gives a testable hypothesis of compensating wage differentials. A panel of quarterly firm level data from 1990 to 1998 are used and the theoretical model is supported by the empirical findings. The result indicates that the workers may not be fully compensated when experiencing high levels of noise in the work area, or when the job involves a high degree of monotonous work, heavy or frequent lifting or poor work postures. Ill health, and thus increased long-term absence, is not highly related to economic variables. However, long-term absence is relatively higher if the firm is troubled with many accidents or near misses. In addition, disamenities for which workers are not fully compensated cause ill health and increased long-term absence.

  17. A General Theoretical Model of Enthalpy-EntropyCompensation

    Institute of Scientific and Technical Information of China (English)

    LIU,Lei; GUO, Qing-Xiang

    2001-01-01

    Enthalpy-entropy compensation remains a mystery in chemistry and biophysics.recent study suggested that the solventreorganization might constitute the physical orihin of the compensation, which was unforumstely not wisely applicable because compensation was also observeserved in solid phade reactions.In this study,a general theoretical model based upon strictmathematical deduction was presented,which indicated thatthe redistribution of the distinguishable subspecies might bethe physical origin of the enthalpy-intropy compensations in solvation and surface adsorption weue discussed.

  18. 38 CFR 3.350 - Special monthly compensation ratings.

    Science.gov (United States)

    2010-07-01

    ... Government expense. (See § 3.552(b)(2) as to continuance following admission for hospitalization... hospitalization where aid and attendance is provided in kind. (c) Ratings under 38 U.S.C. 1114(m). (1) The special... United States Government expense. (See § 3.552(b)(2) as to continuance following admission for...

  19. Differences in perceived fairness and health outcomes in two injury compensation systems: a comparative study.

    Science.gov (United States)

    Elbers, Nieke A; Collie, Alex; Hogg-Johnson, Sheilah; Lippel, Katherine; Lockwood, Keri; Cameron, Ian D

    2016-07-29

    Involvement in a compensation process following a motor vehicle collision is consistently associated with worse health status but the reasons underlying this are unclear. Some compensation systems are hypothesised to be more stressful than others. In particular, fault-based compensation systems are considered to be more adversarial than no-fault systems and associated with poorer recovery. This study compares the perceived fairness and recovery of claimants in the fault-based compensation system in New South Wales (NSW) to the no-fault system in Victoria, Australia. One hundred eighty two participants were recruited via claims databases of the compensation system regulators in Victoria and NSW. Participants were > 18 years old and involved in a transport injury compensation process. The crash occurred 12 months (n = 95) or 24 months ago (n = 87). Perceived fairness about the compensation process was measured by items derived from a validated organisational justice questionnaire. Health outcome was measured by the initial question of the Short Form Health Survey. In Victoria, 84 % of the participants considered the claims process fair, compared to 46 % of NSW participants (χ(2) = 28.54; p fairness. Overall perceived fairness was positively associated with health outcome after adjusting for demographic and injury variables (Adjusted Odds Ratio = 2.8, 95 % CI = 1.4 - 5.7, p = .004). The study shows large differences in perceived fairness between two different compensation systems and an association between fairness and health. These findings are politically important because compensation processes are designed to improve recovery. Lower perceived fairness in NSW may have been caused by potential adversarial aspects of the scheme, such as liability assessment, medical assessments, dealing with a third party for-profit insurance agency, or financial insecurity due to lump sum payments at settlement. This study should encourage an

  20. Three-dimensional reconstruction of coronary stents in vivo based on motion compensated X-ray angiography

    Science.gov (United States)

    Schäfer, Dirk; Movassaghi, Babak; Grass, Michael; Schoonenberg, Gert; Florent, Raoul; Wink, Onno; Klein, Andrew J. P.; Chen, James Y.; Garcia, Joel; Messenger, John C.; Carroll, John D.

    2007-03-01

    The complete expansion of the stent during a percutaneous transluminal coronary angioplasty (PTCA) procedure is essential for treatment of a stenotic segment of a coronary artery. Inadequate expansion of the stent is a major predisposing factor to in-stent restenosis and acute thrombosis. Stents are positioned and deployed by fluoroscopic guidance. Although the current generation of stents are made of materials with some degree of radio-opacity to detect their location after deployment, proper stent expansion is hard to asses. In this work, we introduce a new method for the three-dimensional (3D) reconstruction of the coronary stents in-vivo utilizing two-dimensional projection images acquired during rotational angiography (RA). The acquisition protocol consist of a propeller rotation of the X-ray C-arm system of 180°, which ensures sufficient angular coverage for volume reconstruction. The angiographic projections were acquired at 30 frames per second resulting in 180 projections during a 7 second rotational run. The motion of the stent is estimated from the automatically tracked 2D coordinates of the markers on the balloon catheter. This information is used within a motion-compensated reconstruction algorithm. Therefore, projections from different cardiac phases and motion states can be used, resulting in improved signal-to-noise ratio of the stent. Results of 3D reconstructed coronary stents in vivo, with high spatial resolution are presented. The proposed method allows for a comprehensive and unique quantitative 3D assessment of stent expansion that rivals current X-ray and intravascular ultrasound techniques.

  1. 自适应同态对数光照补偿%Adaptive logarithm for facial illumination compensation based on homomorphic gomomorphic module

    Institute of Scientific and Technical Information of China (English)

    郑伟华; 戴永

    2011-01-01

    人脸检测有广泛的应用前景,但目前的许多人脸检测算法对光照有一定的要求,过亮过暗偏光图像使检测率急剧下降.提出一种自适应同态对数光照补偿方法,用对数函数作为基函数,使变换后的图像符合人的视觉特点;设置对数函数的平移系数,使变换对各种程度过暗过亮偏光阴影图像都可以进行有效的补偿:引入同态补偿公式来补偿光照的同时增强图像细节,使变换后的图像更清晰.实验结果表明,该方法对过暗过亮的人脸图像都可以进行有效的光照补偿,有助于提高人脸检测率.%Face detection has wide applications. But many of the detection algorithms are sensitive to illumination variation. Detection rates usually drop quickly if the illumination is too bright, too dark, or non-uniform illumination. This paper proposed a adaptive logarithm illumination compensation method based neighbour remediation technique, the method use logarithm function as primary function, therefore it' s true of human visual trait; and setup the offset' s coefficients of logarithm function to solve the illumination problem in varying degree, thus this method is ability of compensation of all types of image in varying degrees through adjusting the coefficients; and introduce a remediation technique based neighbour area to reduce illumination influence and enhance image details, so the resource of the image which transformed has been improved. Experimental results show that this method is effective in compensating facial images of over-lighting and over-shading, and it is beneficial to improve the facial detection rate.

  2. Principle and Design of a Single-phase Inverter Based Grounding System for Neutral-to-ground Voltage Compensation in Distribution Networks

    DEFF Research Database (Denmark)

    Wang, Wen; Yan, Lingjie; Zeng, Xiangjun

    2017-01-01

    Neutral-to-ground overvoltage may occur in non-effectively grounded power systems because of the distributed parameters asymmetry and resonance between Petersen coil and distributed capacitances. Thus, the constraint of neutral-to-ground voltage is critical for the safety of distribution networks....... In this paper, an active grounding system based on single-phase inverter and its control parameter design method is proposed to achieve this objective. Relationship between its output current and neutral-to-ground voltage is derived to explain the principle of neutral-to-ground voltage compensation. Then...... margin subjecting to large range of load change. The PI method is taken as the comparative method and the performances of both control methods are presented in detail. Experimental results prove the effectiveness and novelty of the proposed grounding system and control method....

  3. Stock Option Compensation and Managerial Turnover

    OpenAIRE

    Raluca Georgiana NASTASESCU

    2009-01-01

    This study examines the association between managerial turnover and equity-based compensation. I investigate whether stock options act to bond executives to their firms and whether retention of managers is a motivation of companies in designing CEO incentive contracts. The results show that stock options do negatively influence the probability of a CEO leaving the company. The monetary cost of losing the value of equity-based compensation package keeps the manager with his company. I also fin...

  4. 一种基于光照变化补偿的颜色识别方法%Color Recognition Method Based on Illumination Changed Compensation

    Institute of Scientific and Technical Information of China (English)

    潘浩; 杨宜民

    2012-01-01

    针对RoboCup中型组足球机器人比赛中光照变化会使颜色发生色彩漂移,影响颜色识别的准确性问题,提出一种基于光照变化补偿的颜色识别方法.该方法首先利用球的历史信息预测球的位置,然后在较小的区域内用基于色调直方图反向投影的方法找到球后,通过球的亮度直方图的变化计算出光照变化率,用于动态补偿颜色查找表.实验表明该方法能提高颜色识别的光照自适应性.%For the problem that illumination change causes color shiftting and affects the accuracy of color recognition in the medium group of RoboCup competition, this paper proposes a color recognition method based on illumination changed compensation. This method first uses the historical information of the ball to predict its position. After finding the ball by using the method of reverse projection based on color histogram in a small area, it calculates illumination changing rate through the changes of ball's brightness histogram to dynamically compensate the color lookup table. Experiments show that this method can improve the illumination adaptive of color recognition.

  5. Method for Analysis of an Offshore Heave Compensator

    Directory of Open Access Journals (Sweden)

    Gwi-Nam Kim

    2016-02-01

    Full Text Available A heave compensation system consists of a drill string compensator (DSC and an active heave compensator (AHC cylinder, which together produce control force over an oil pressure system suitable for transmission of considerable power and compensating for heaving motion of the hull during drilling work. In this study, a heave compensator of an oil pressure system was simulated to draw a conclusion, which was verified by comparison with the result of a test conducted using an actual miniature model. The compensation rate was 95%, based on which the dynamic behaviors of an actual-size heave compensator were presumed. Furthermore, the speed of each cylinder and the acceleration of heave can be determined and used to fabricate an actual-size heave compensator.

  6. Executive compensation and firm performance: Evidence from Indian firms

    Directory of Open Access Journals (Sweden)

    Mehul Raithatha

    2016-09-01

    Full Text Available The study examines the relationship between executive compensation and firm performance among Indian firms. The evidence suggests that firm performance measured by accounting, as well as market-based measures, significantly affects executive compensation. We also test for the presence of persistence in executive compensation by employing the system-generalised methods of moments (GMM estimator. We find significant persistence in executive compensation among the sample firms. Further, we report the absence of pay–performance relationship among the smaller sample firms and business group affiliated firms. Thus, our findings cast doubts over the performance-based executive compensation practices of Indian business group affiliated firms.

  7. Workers Compensation Claim Data -

    Data.gov (United States)

    Department of Transportation — This data set contains DOT employee workers compensation claim data for current and past DOT employees. Types of data include claim data consisting of PII data (SSN,...

  8. 基于补偿电路的SRAM读操作跟踪电路设计%SRAM read tracking circuit design based on compensation circuit

    Institute of Scientific and Technical Information of China (English)

    李二亮; 张立军; 李有忠; 张其笑; 姜伟; 胡玉青

    2015-01-01

    在传统静态随机存储器(SRAM)读操作跟踪电路中,生产工艺和温度的偏差会直接影响到对SRAM中存储数据的正确读取。因此,在本文中,我们采用工艺拐点补偿和温度补偿的方法,设计出了新型SRAM读操作跟踪电路。所设计跟踪电路,通过在不同工艺拐点和不同温度的情况下,对时序追踪字线DBL补偿不同大小的电流,从而减小灵敏放大器输入位线电压差对工艺拐点和温度的敏感度。有效减小了工艺拐点和温度对于SRAM读操作的影响,提高了SRAM的良率。基于SMIC 40nm CMOS工艺,对上述读操作跟踪电路进行了仿真,并且分别对补偿前后进行了10000次蒙特卡罗仿真与比较,仿真结果验证了所设计电路的可靠性和有效性。%In conventional SRAM read tracking circuit, process and temperature fluctuations may cause SRAM read failure. Thus, in this paper, a novel read tracking circuit of SRAM is put up using corner compensation technology and temperature compensation in this paper. The proposed tracking circuit compensates the dummy bit line for different current when working in different process corner and temperature condition, which dramatically reduce the impact of process corner and temperature, and enhance the yield of SRAM. The proposed circuit is simulated based on the SIMC's 40nm CMOS process , and the result proved the proposed circuit is valid and reliably.

  9. ACTS Rain Fade Compensation

    Science.gov (United States)

    Coney, Thom A.

    1996-01-01

    Performance status of the Adaptive Rain Fade Compensation includes: (1) The rain fade protocol is functional detecting fades, providing an additional 10 dB of margin and seamless transitions to and from coded operation; (2) The stabilization of the link margins and the optimization of rain fade decision thresholds has resulted in improved BER performance; (3) Characterization of the fade compensation algorithm is ongoing.

  10. Dosage compensation in birds

    OpenAIRE

    McQueen, H A; McBride, D; Miele, G; Bird, A.P.; Clinton, M

    2001-01-01

    The Z and W sex chromosomes of birds have evolved independently from the mammalian X and Y chromosomes [1]. Unlike mammals, female birds are heterogametic (ZW), while males are homogametic (ZZ). Therefore male birds, like female mammals, carry a double dose of sex-linked genes relative to the other sex. Other animals with nonhomologous sex chromosomes possess "dosage compensation" systems to equalize the expression of sex-linked genes. Dosage compensation occurs in animals as diverse as mamma...

  11. 三相软开关PWM变流器电流极性检测与电流补偿方法%Current Polarity Detection and Current Compensation Strategy for PAC Based Three-Phase ZVS PWM Converter

    Institute of Scientific and Technical Information of China (English)

    屈克庆; 陈国呈; 孙承波

    2005-01-01

    A novel software implementation for current polarity detection and current compensation is presented. For a three-phase zero-voltage soft-switching (ZVS) PWM converter based on phase and amplitude control (PAC), when saw-tooth carriers with alternate positive and negative slopes are adopted, the positive or negative slopes are chosen according to the phase current polarity. Since polarity reversal causes current distortion, current at the instant of reversal should be compensated for. Based on the characteristic of unity power factor converter in rectification and regeneration modes, a software implementation for current polarity detection is proposed.Distortion of current zero-crossing caused by using saw-tooth carriers with alternate positive and negative slopes is analyzed, and the relevant compensation method is proposed. Experimental study with a 1.5 kW device shows that phase current has a small harmonic content and power factor is high both in rectification and regeneration modes.

  12. Advanced median method for timing jitter compensation

    Institute of Scientific and Technical Information of China (English)

    Wang Chen; Zhu Jiangmiao; Jan Verspecht; Liu Mingliang; Li Yang

    2008-01-01

    Timing jitter is one of the main factors that influence on the accuracy of time domain precision measurement. Timing jitter compensation is one of the problems people concern. Because of the flaws of median method, PDF deconvolution method and synthetic method, we put forward a new method for timing jitter compensation, which is called advanced median method. The theory of the advanced median method based on probability and statistics is analyzed, and the process of the advanced median method is summarized in this paper. Simulation and experiment show that compared with other methods, the new method could compensate timing jitter effectively.

  13. Lossless Compression of Video using Motion Compensation

    DEFF Research Database (Denmark)

    Martins, Bo; Forchhammer, Søren

    1998-01-01

    We investigate lossless coding of video using predictive coding andmotion compensation. The methods incorporate state-of-the-art lossless techniques such ascontext based prediction and bias cancellation, Golomb coding, high resolution motion field estimation,3d-dimensional predictors, prediction...... using one or multiple previous images, predictor dependent error modelling, and selection of motion field by code length. For slow pan or slow zoom sequences, coding methods that use multiple previous images are up to 20% better than motion compensation using a single previous image and up to 40% better...... than coding that does not utilize motion compensation....

  14. Participant characteristics associated with greater reductions in waist circumference during a four-month, pedometer-based, workplace health program

    Directory of Open Access Journals (Sweden)

    Freak-Poli Rosanne LA

    2011-10-01

    Full Text Available Abstract Background Workplace health programs have demonstrated improvements in a number of risk factors for chronic disease. However, there has been little investigation of participant characteristics that may be associated with change in risk factors during such programs. The aim of this paper is to identify participant characteristics associated with improved waist circumference (WC following participation in a four-month, pedometer-based, physical activity, workplace health program. Methods 762 adults employed in primarily sedentary occupations and voluntarily enrolled in a four-month workplace program aimed at increasing physical activity were recruited from ten Australian worksites in 2008. Seventy-nine percent returned at the end of the health program. Data included demographic, behavioural, anthropometric and biomedical measurements. WC change (before versus after was assessed by multivariable linear and logistic regression analyses. Seven groupings of potential associated variables from baseline were sequentially added to build progressively larger regression models. Results Greater improvement in WC during the program was associated with having completed tertiary education, consuming two or less standard alcoholic beverages in one occasion in the twelve months prior to baseline, undertaking less baseline weekend sitting time and lower baseline total cholesterol. A greater WC at baseline was strongly associated with a greater improvement in WC. A sub-analysis in participants with a 'high-risk' baseline WC revealed that younger age, enrolling for reasons other than appearance, undertaking less weekend sitting time at baseline, eating two or more pieces of fruit per day at baseline, higher baseline physical functioning and lower baseline body mass index were associated with greater odds of moving to 'low risk' WC at the end of the program. Conclusions While employees with 'high-risk' WC at baseline experienced the greatest improvements in

  15. Facial illumination compensation based on wavelet quotient image%基于小波商图像的人脸光照补偿

    Institute of Scientific and Technical Information of China (English)

    刘丽华; 王映辉; 邓方安

    2009-01-01

    Face recognition under complex illumination conditions is still an difficult but must deal with problem an effective illumination compensation method is proposed: Based on quotient image theory, the illumination condition is estimated on facial wavelet de-dimension illumination training set. Moreover, the aim of facial illumination compensation is implemented by two basic strategies of adding light and reducing light. Compared with traditional quotient image theory, this method enhances arithmetic efficiency by wavelet transform. The experimental results show that the improved methods get a very competitive recognition rate with low computational cost.%复杂光照条件下的人脸识别是一个困难但需迫切解决的问题,为此提出了一种有效的光照补偿算法.该方法根据人脸光照线性变换子空间理论--商图像理论,构造了小波低维训练集,实现了对待识别图像的光照条件估计,并且通过加光和去光策略增强了光照补偿效果.与传统商图像理论相比,该方法利用小波分解,提高的算法执行效率,实验结果表明,该算法以较小的代价取得了较高的识别性能.

  16. Compensator configurations for load currents' symmetrization

    Science.gov (United States)

    Rusinaru, D.; Manescu, L. G.; Dinu, R. C.

    2016-02-01

    This paper approaches aspects regarding the mitigation effects of asymmetries in 3-phase 3-wire networks. The measure consisting in connecting of load current symmetrization devices at the load coupling point is presented. A time-variation of compensators parameters is determined as a function of the time-recorded electrical values. The general sizing principle of the load current symmetrization reactive components is based on a simple equivalent model of the unbalanced 3-phase loads. By using these compensators a certain control of the power components transits is ensured in the network. The control is based on the variations laws of the compensators parameters as functions of the recorded electrical values: [B] = [T]·[M]. The link between compensator parameters and measured values is ensured by a transformation matrix [T] for each operation conditions of the supply network. Additional conditions for improving of energy and efficiency performance of the compensator are considered: i.e. reactive power compensation. The compensator sizing algorithm was implemented into a MATLAB environment software, which generate the time-evolution of the parameters of load current symmetrization device. The input data of application takes into account time-recording of the electrical values. By using the compensator sizing software, some results were achieved for the case of a consumer connected at 20 kV busbar of a distribution substation, during 24 hours measurement session. Even the sizing of the compensators aimed some additional network operation aspects (power factor correction) correlated with the total or major load symmetrizations, the harmonics aspects of the network values were neglected.

  17. Twelve months of implementation of health care performance-based financing in Burkina Faso: A qualitative multiple case study.

    Science.gov (United States)

    Ridde, Valéry; Yaogo, Maurice; Zongo, Sylvie; Somé, Paul-André; Turcotte-Tremblay, Anne-Marie

    2017-07-03

    To improve health services' quantity and quality, African countries are increasingly engaging in performance-based financing (PBF) interventions. Studies to understand their implementation in francophone West Africa are rare. This study analysed PBF implementation in Burkina Faso 12 months post-launch in late 2014. The design was a multiple and contrasted case study involving 18 cases (health centres). Empirical data were collected from observations, informal (n = 224) and formal (n = 459) interviews, and documents. Outside the circle of persons trained in PBF, few in the community had knowledge of it. In some health centres, the fact that staff were receiving bonuses was intentionally not announced to populations and community leaders. Most local actors thought PBF was just another project, but the majority appreciated it. There were significant delays in setting up agencies for performance monitoring, auditing, and contracting, as well as in the payment. The first audits led rapidly to coping strategies among health workers and occasionally to some staging beforehand. No community-based audits had yet been done. Distribution of bonuses varied from one centre to another. This study shows the importance of understanding the implementation of public health interventions in Africa and of uncovering coping strategies. © 2017 The Authors. The International Journal of Health Planning and Management Published by John Wiley & Sons Ltd.

  18. Compensating Large PMD by Four Free degrees in an OTDM System

    Institute of Scientific and Technical Information of China (English)

    Li Tangjun; Wang Muguang; Cui Jie; Luo Ri; Jian Shuisheng

    2003-01-01

    In this paper, by introducing a two-stages polarization mode dispersion (PMD) compensator after a optical fiber link with a large PMD, we compensated over 270ps first-order and 2000ps2 high-order PMD in a optical fiber link with super high PMD. Our experimental results shows that, the compensators based on the two-stages of compensator can be used to PMD compensation in a 20Gb/s OTDM system with 60 km high PMD fiber. Before compensation,270ps DGD is became into max. 7ps after compensation. At simultaneity, the tunable FBG have a function of dispersion compensation.

  19. 基于多项式模型和 BP神经网络的光纤陀螺温度补偿%TEMPERATURE COMPENSATION FOR FOG BASED ON POLYNOMIAL MODEL AND BP NEURAL NETWORK

    Institute of Scientific and Technical Information of China (English)

    席绪奇; 姚志成; 何志昆; 赵曦晶

    2013-01-01

    在对开环干涉型光纤陀螺仪大量实验数据分析的基础上,分别对光纤陀螺仪零位温度漂移建立BP神经网络温度补偿,标度因数与温度、输入角速率建立多项式模型。利用建立的模型对实验数据进行温度补偿。补偿结果表明,BP神经网络补偿效果优于多项式模型,零偏和零偏稳定性减小了一个数量级,补偿效果明显。%Based on analysing lots of experimental data of open-loop interference type fibre optic gyro (FOG), we set up the BP neural network temperature compensation for zero temperature drift of FOG and the polynomial model for scale factor , temperature and input angular rate respectively .The established model is used to make temperature compensation on experimental data .The results of compensation show that, BP neural network is better than polynomial model in compensation effect , the zero-bias and the stability of zero-bias is reduced by an order of magnitude , the compensation effect is noticeable .

  20. Static VAR Compensator-Based Voltage Regulation for Variable-Speed Prime Mover Coupled Single-Phase Self-Excited Induction Generator

    Science.gov (United States)

    Ahmed, Tarek; Noro, Osamu; Hiraki, Eiji; Nakaoka, Mutsuo

    In this paper, the single-phase static VAR compensator (SVC) is applied to regulate and stabilize smoothly the generated output voltage of the single-phase self-excited induction generator (single-phase SEIG) driven by a variable-speed prime mover (VSPM) under the conditions of inductive load variations and prime mover speed changes. The conventional fixed gain PI controller-based feedback control scheme is employed to adjust the equivalent capacitance of the single-phase SVC composed of the fixed excitation capacitor (FC) in parallel with the thyristor switched capacitor (TSC) and the thyristor controlled reactor TCR. A PI closed-loop feedback voltage control scheme based on the SVC for the single-phase SEIG coupled by a VSPM prototype set-up is established. The closed-loop feedback output voltage responses in the single-phase SEIG coupled by a VSPM with different inductive load variations using the single-phase SVC with the PI controller are considered and discussed herein. Based on the SVC with the PI controller closed-loop feedback voltage regulation scheme, the experimental results for the single-phase SEIG driven by a VSPM are illustrated and proved its practical effectiveness in terms of the fast response and the high performances.

  1. First steps towards ultrasound-based motion compensation for imaging and therapy: calibration with an optical system and 4D PET imaging

    Directory of Open Access Journals (Sweden)

    Julia eSchwaab

    2015-11-01

    Full Text Available Target motion, particularly in the abdomen, due to respiration or patient movement is still a challenge in many diagnostic and therapeutic processes. Hence, methods to detect and compensate this motion are required. Diagnostic ultrasound represents a non-invasive and dose-free alternative to fluoroscopy, providing more information about internal target motion than respiration belt or optical tracking.The goal of this project is to develop an ultrasound based motion tracking for real time motion correction in radiation therapy and diagnostic imaging, notably in 4D positron emission tomography (PET. In this work, a workflow is established to enable the transformation of ultrasound tracking data to the coordinates of the treatment delivery or imaging system – even if the ultrasound probe is moving due to respiration. It is shown that the ultrasound tracking signal is equally adequate for 4D PET image reconstruction as the clinically used respiration belt and provides additional opportunities in this concern. Furthermore, it is demonstrated that the ultrasound probe being within the PET field of view generally has no relevant influence on the image quality. The accuracy and precision of all the steps in the calibration workflow for ultrasound tracking based 4D PET imaging are found to be in an acceptable range for clinical implementation. Eventually, we show in vitro that an ultrasound based motion tracking in absolute room coordinates with a moving US-transducer is feasible.

  2. Results of the 2016 AORN Salary and Compensation Survey.

    Science.gov (United States)

    Bacon, Donald R; Stewart, Kim A

    2016-12-01

    AORN conducted its 14th annual compensation survey for perioperative nurses in June 2016. A multiple regression model was used to examine how several variables, including job title, education level, certification, experience, and geographic region, affect nurse compensation. Comparisons between the 2016 data and data from previous years are presented. The effects of other forms of compensation (eg, on-call compensation, overtime, bonuses, shift differentials, benefits) on base compensation rates also are examined. Additional analyses explore the effect of the economic downturn on the perioperative work environment. Copyright © 2016 AORN, Inc. Published by Elsevier Inc. All rights reserved.

  3. Stealth Compensation via Retirement Benefits

    OpenAIRE

    Bebchuk, Lucian Arye

    2004-01-01

    This paper analyzes an important form of "stealth compensation" provided to managers of public companies. We show how boards have been able to camouflage large amounts of executive compensation through the use of retirement benefits and payments. Our study illustrates the significant role that camouflage and stealth compensation play in the design of compensation arrangements. It also highlights the importance of having information about compensation arrangements not only publicly available b...

  4. Stealth Compensation Via Retirement Benefits

    OpenAIRE

    Lucian Arye Bebchuk; Fried, Jesse M.

    2004-01-01

    This paper analyzes an important form of "stealth compensation" provided to managers of public companies. We show how boards have been able to camouflage large amount of executive compensation through the use of retirement benefits and payments. Our study highlights the significant role that camouflage and stealth compensation play in the design of compensation arrangements. Our study also highlights the significance of whether information about compensation arrangements is not merely publicl...

  5. Estimation of the monthly average daily solar radiation using geographic information system and advanced case-based reasoning.

    Science.gov (United States)

    Koo, Choongwan; Hong, Taehoon; Lee, Minhyun; Park, Hyo Seon

    2013-05-07

    The photovoltaic (PV) system is considered an unlimited source of clean energy, whose amount of electricity generation changes according to the monthly average daily solar radiation (MADSR). It is revealed that the MADSR distribution in South Korea has very diverse patterns due to the country's climatic and geographical characteristics. This study aimed to develop a MADSR estimation model for the location without the measured MADSR data, using an advanced case based reasoning (CBR) model, which is a hybrid methodology combining CBR with artificial neural network, multiregression analysis, and genetic algorithm. The average prediction accuracy of the advanced CBR model was very high at 95.69%, and the standard deviation of the prediction accuracy was 3.67%, showing a significant improvement in prediction accuracy and consistency. A case study was conducted to verify the proposed model. The proposed model could be useful for owner or construction manager in charge of determining whether or not to introduce the PV system and where to install it. Also, it would benefit contractors in a competitive bidding process to accurately estimate the electricity generation of the PV system in advance and to conduct an economic and environmental feasibility study from the life cycle perspective.

  6. Change in health-related quality of life amongst participants in a 4-month pedometer-based workplace health program.

    Science.gov (United States)

    Harding, Jessica; Freak-Poli, Rosanne Laura Armida; Backholer, Kathryn; Peeters, Anna

    2013-05-01

    Regular physical activity (PA) is associated with a reduced risk for chronic health conditions and improved health-related quality of life (HRQoL). Efforts to increase PA have included workplace health promotion. Currently, little is known about the effect of these programs on overall HRQoL. To evaluate whether participation in a pedometer-based PA program in the workplace was associated with changes in HRQoL. 487 voluntary employees enrolled in a health program completed the SF-12 Health Survey at baseline and 4 months. Change in Physical and Mental component summary scores (PCS; MCS) was assessed with multivariable regression analysis, adjusting for covariates. Participation in the program was associated with an increase of 1.5 MCS units (95% CI: 0.76, -2.09). Greater improvements in MCS were observed in those reporting an increased level of PA during the program [1.9 (CI: 0.78, 2.92) versus 0.9 (CI: -0.12, 2.03)] and a lower baseline MCS score [6.3 (CI: 4.80, 7.62) versus -1.5 (CI: -2.21, -0.80)]. No change in PCS was observed. Participation in this workplace PA program was associated with improvements in the mental component of HRQoL. We recommend the use of a broad perspective of health be used in both the implementation and evaluation of workplace PA programs.

  7. Interaction of osmoregulatory and acid-base compensation in white sturgeon (Acipenser transmontanus) during exposure to aquatic hypercarbia and elevated salinity.

    Science.gov (United States)

    Shaughnessy, Ciaran A; Baker, Dan W; Brauner, Colin J; Morgan, John D; Bystriansky, Jason S

    2015-09-01

    Migratory fishes encounter a variety of environmental conditions, including changes in salinity, temperature and dissolved gases, and it is important to understand how these fishes are able to acclimate to multiple environmental stressors. The gill is the primary site of both acid-base balance and ion regulation in fishes. Many ion transport mechanisms involved with acid-base compensation are also required for the regulation of plasma Na(+) and Cl(+), the predominant extracellular ions, potentially resulting in a strong interaction between ionoregulation and acid-base regulation. The present study examined the physiological interaction of elevated dissolved CO2 (an acid-base disturbance) on osmoregulation during seawater acclimation (an ionoregulatory disturbance) in juvenile white sturgeon (Acipenser transmontanus). Blood pH (pHe), plasma [HCO3 (-)], [Na(+)], [Cl(-)] and osmolality, white muscle water content, and gill Na(+)/K(+)-ATPase (NKA) and Na(+)/K(+)/2Cl(-) co-transporter (NKCC) abundance were examined over a 10 day seawater (SW) acclimation period under normocarbia (NCSW) or during prior and continued exposure to hypercarbia (HCSW), and compared with a normocarbic freshwater (NCFW) control. Hypercarbia induced a severe extracellular acidosis (from pH 7.65 to pH 7.2) in HCSW sturgeon, and these fish had a 2-fold greater rise in plasma osmolarity over NCSW by day 2 of SW exposure. Interestingly, pHe recovery in HCSW was associated more prominently with an elevation in plasma Na(+) prior to osmotic recovery and more prominently with a reduction in plasma Cl(-) following osmotic recovery, indicating a biphasic response as the requirements of osmoregulation transitioned from ion-uptake to ion-excretion throughout SW acclimation. These results imply a prioritization of osmoregulatory recovery over acid-base recovery in this period of combined exposure to acid-base and ionoregulatory disturbances.

  8. The fitness of apps: a theory-based examination of mobile fitness app usage over 5 months.

    Science.gov (United States)

    Herrmann, Lynn Katherine; Kim, Jinsook

    2017-01-01

    There are thousands of fitness-related smartphone applications ("apps") available for free and purchase, but there is uncertainty if these apps help individuals achieve and maintain personal fitness. Technology usage attrition is also a concern among research studies on health technologies. Usage of three fitness apps was examined over 5 months to assess adherence and effectiveness. Initially, 64 participants downloaded three free apps available on Android and iOS and 47 remained in the study until posttest. With a one group pre-posttest design and checkpoints at months 1, 3, and 5, exercise and exercise with fitness apps were examined in the framework of the Theory of Planned Behavior (TPB) using a validated survey. Apps were selected based on their function from the Functional Triad. Perceived fitness was also measured. T-tests, sign tests, Fisher's exact tests, and linear and logistic regression were used to compare pre to posttests and users to non-users of the apps. Forty-seven participants completed both pre and posttests. Individual item scores indicated no significant change pre to posttest except for decreases observed in usefulness of using apps for exercise (attitude) (-0.78, Papps (subjective norm) (-1.02, Papps (perceived behavioral control) (-1.29, Papps over the next 2 weeks (behavioral intention) (Papps (-1.72, Papps (-2.56, Papp users (n=32) to non-users (n=15), there was only a significant difference in subscale total scores at posttest for attitude toward exercising using apps, which was significantly more favorable among users than non-users (32.3 vs. 27.6, PApp usage and effectiveness appears to have a connection to usefulness (attitude) and to perceived difficulties of exercising using apps (perceived behavioral control). Exercise and exercise using apps are not influenced by peer influence (subjective norm). Intention to exercise using these particular apps decreased (behavioral intention). Those who utilized the apps were more likely to have

  9. Parallel implementation of high-speed, phase diverse atmospheric turbulence compensation method on a neural network-based architecture

    Science.gov (United States)

    Arrasmith, William W.; Sullivan, Sean F.

    2008-04-01

    Phase diversity imaging methods work well in removing atmospheric turbulence and some system effects from predominantly near-field imaging systems. However, phase diversity approaches can be computationally intensive and slow. We present a recently adapted, high-speed phase diversity method using a conventional, software-based neural network paradigm. This phase-diversity method has the advantage of eliminating many time consuming, computationally heavy calculations and directly estimates the optical transfer function from the entrance pupil phases or phase differences. Additionally, this method is more accurate than conventional Zernike-based, phase diversity approaches and lends itself to implementation on parallel software or hardware architectures. We use computer simulation to demonstrate how this high-speed, phase diverse imaging method can be implemented on a parallel, highspeed, neural network-based architecture-specifically the Cellular Neural Network (CNN). The CNN architecture was chosen as a representative, neural network-based processing environment because 1) the CNN can be implemented in 2-D or 3-D processing schemes, 2) it can be implemented in hardware or software, 3) recent 2-D implementations of CNN technology have shown a 3 orders of magnitude superiority in speed, area, or power over equivalent digital representations, and 4) a complete development environment exists. We also provide a short discussion on processing speed.

  10. Compensation neurosis rides again.

    Science.gov (United States)

    Levy, A

    1992-01-01

    Compensation neurosis (CN), also known as accident neurosis, has generally not been considered to be a 'real' disorder. In 1961 it was seemingly laid to rest by Henry Miller, a distinguished neurologist, in a sharp article which appeared in the British Medical Journal. Miller's view of patients who presented psychological symptoms following accidents or traumas was suspicious. Compensated or not, his view seemed to be that they should have their legal process finished as quickly as possible and then they will miraculously convalescence. Miller's work, it appeared, was the coup de grâce for this ill-defined diagnosis. Today, however, compensation neurosis seems to ride again. After a prolonged silence in the psychiatric literature, new papers are emerging, strongly suggesting that this vanishing diagnosis be reconsidered. This new trend will be presented.

  11. Power factor compensation

    Energy Technology Data Exchange (ETDEWEB)

    Barra R, Felipe [Schneider Electric Chile (Chile)

    2010-07-01

    Every company is looking for ways to increase productivity as a way to gain a competitive advantage. Energy is a significant element in making any product and so it is important to assess production processes from an energy perspective. This paper discusses the impact of power factor compensation on energy efficiency. The life cycle solution for energy efficiency involves optimization of active energy using automation and regulation. A brief explanation is given of how each component of a company plays a part in this cycle. Examples include simulations and analysis, modeling, performance monitoring facilities, and environmental sustainability. Reactive energy suppliers and the installation of capacitors are also explained. Types of compensation include fixed and automation compensations. Economic advantages include a reduction in the electricity bill and active energy consumption. Technical advantages include reduction in voltage drop and an increase in available power. The power correction factor also improves reliability and contributes to conservation of the environment.

  12. Reconstructing ERP amplitude effects after compensating for trial-to-trial latency jitter: A solution based on a novel application of residue iteration decomposition.

    Science.gov (United States)

    Ouyang, Guang; Sommer, Werner; Zhou, Changsong

    2016-11-01

    Stimulus-locked averaged event-related potentials (ERPs) are among the most frequently used signals in Cognitive Neuroscience. However, the late, cognitive or endogenous ERP components are often variable in latency from trial to trial in a component-specific way, compromising the stability assumption underlying the averaging scheme. Here we show that trial-to-trial latency variability of ERP components not only blurs the average ERP waveforms, but may also attenuate existing or artificially induce condition effects in amplitude. Hitherto this problem has not been well investigated. To tackle this problem, a method to measure and compensate component-specific trial-to-trial latency variability is required. Here we first systematically analyze the problem of single trial latency variability for condition effects based on simulation. Then, we introduce a solution by applying residue iteration decomposition (RIDE) to experimental data. RIDE separates different clusters of ERP components according to their time-locking to stimulus onsets, response times, or neither, based on an algorithm of iterative subtraction. We suggest to reconstruct ERPs by re-aligning the component clusters to their most probable single trial latencies. We demonstrate that RIDE-reconstructed ERPs may recover amplitude effects that are diminished or exaggerated in conventional averages by trial-to-trial latency jitter. Hence, RIDE-corrected ERPs may be a valuable tool in conditions where ERP effects may be compromised by latency variability.

  13. The fitness of apps: a theory-based examination of mobile fitness app usage over 5 months

    Science.gov (United States)

    Kim, Jinsook

    2017-01-01

    Background There are thousands of fitness-related smartphone applications (“apps”) available for free and purchase, but there is uncertainty if these apps help individuals achieve and maintain personal fitness. Technology usage attrition is also a concern among research studies on health technologies. Methods Usage of three fitness apps was examined over 5 months to assess adherence and effectiveness. Initially, 64 participants downloaded three free apps available on Android and iOS and 47 remained in the study until posttest. With a one group pre-posttest design and checkpoints at months 1, 3, and 5, exercise and exercise with fitness apps were examined in the framework of the Theory of Planned Behavior (TPB) using a validated survey. Apps were selected based on their function from the Functional Triad. Perceived fitness was also measured. T-tests, sign tests, Fisher’s exact tests, and linear and logistic regression were used to compare pre to posttests and users to non-users of the apps. Results Forty-seven participants completed both pre and posttests. Individual item scores indicated no significant change pre to posttest except for decreases observed in usefulness of using apps for exercise (attitude) (−0.78, P<0.01), peer influence on exercise (subjective norm) (−0.51, P<0.05), peer influence on exercise with apps (subjective norm) (−1.02, P<0.01), perceived difficulties in exercising with apps (perceived behavioral control) (−1.29, P<0.001), and the expected frequency of exercise with apps over the next 2 weeks (behavioral intention) (P<0.0001 in a sign test). Subscale total scores indicated significant decreases in subjective norm regarding exercise (−0.72, P<0.05), subjective norm regarding exercise with apps (−1.72, P<0.01), and perceived behavioral control over exercising with apps (−2.56, P<0.01) between pre and posttest. When comparing app users (n=32) to non-users (n=15), there was only a significant difference in subscale total

  14. Repeat Colonoscopy within 6 Months after Initial Outpatient Colonoscopy in Ontario: A Population-Based Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Lawrence Paszat

    2017-01-01

    Full Text Available Background. The goal of this study is to examine utilization of early repeat colonoscopy ≤ 6 months after an index procedure. Methods. We identified persons having repeat colonoscopy ≤ 6 months following outpatient colonoscopy without prior colonoscopy ≤ 5 years or prior diagnosis of colorectal cancer (CRC. We modeled repeat colonoscopy using a generalized estimating equation with an exchangeable correlation structure to account for clustering of patients by endoscopist. Results. The population included 334,663 persons, 7,892 (2.36% of whom had an early repeat colonoscopy within 6 months. Overall, endoscopist prior year colonoscopy volume was inversely related to repeat ≤ 6 months. Repeat colonoscopy ≤ 6 months varied by the clinical setting of the index colonoscopy (adjusted OR = 1.41 (95% CI 1.29–1.55 at nonhospital facilities compared to teaching or community hospitals. Among those who had polypectomy or biopsy, the adjusted OR for early repeat ≤ 6 months was elevated among those whose index colonoscopy was at a nonhospital facility (OR 1.44, 95% CI 1.30–1.60, compared to those at a teaching hospital or community hospital. Conclusions. Repeat colonoscopy ≤ 6 months after an index procedure is associated with the clinical setting of the index colonoscopy.

  15. Compensating for estimation smoothing in kriging

    Science.gov (United States)

    Olea, R.A.; Pawlowsky, Vera

    1996-01-01

    Smoothing is a characteristic inherent to all minimum mean-square-error spatial estimators such as kriging. Cross-validation can be used to detect and model such smoothing. Inversion of the model produces a new estimator-compensated kriging. A numerical comparison based on an exhaustive permeability sampling of a 4-fr2 slab of Berea Sandstone shows that the estimation surface generated by compensated kriging has properties intermediate between those generated by ordinary kriging and stochastic realizations resulting from simulated annealing and sequential Gaussian simulation. The frequency distribution is well reproduced by the compensated kriging surface, which also approximates the experimental semivariogram well - better than ordinary kriging, but not as well as stochastic realizations. Compensated kriging produces surfaces that are more accurate than stochastic realizations, but not as accurate as ordinary kriging. ?? 1996 International Association for Mathematical Geology.

  16. Adverse events following 12 and 18 month vaccinations: a population-based, self-controlled case series analysis.

    Directory of Open Access Journals (Sweden)

    Kumanan Wilson

    Full Text Available BACKGROUND: Live vaccines have distinct safety profiles, potentially causing systemic reactions one to 2 weeks after administration. In the province of Ontario, Canada, live MMR vaccine is currently recommended at age 12 months and 18 months. METHODS: Using the self-controlled case series design we examined 271,495 12 month vaccinations and 184,312 18 month vaccinations to examine the relative incidence of the composite endpoint of emergency room visits or hospital admissions in consecutive one day intervals following vaccination. These were compared to a control period 20 to 28 days later. In a post-hoc analysis we examined the reasons for emergency room visits and the average acuity score at presentation for children during the at-risk period following the 12 month vaccine. RESULTS: Four to 12 days post 12 month vaccination, children had a 1.33 (1.29-1.38 increased relative incidence of the combined endpoint compared to the control period, or at least one event during the risk interval for every 168 children vaccinated. Ten to 12 days post 18 month vaccination, the relative incidence was 1.25 (95%, 1.17-1.33 which represented at least one excess event for every 730 children vaccinated. The primary reason for increased events was statistically significant elevations in emergency room visits following all vaccinations. There were non-significant increases in hospital admissions. There were an additional 20 febrile seizures for every 100,000 vaccinated at 12 months. CONCLUSIONS: There are significantly elevated risks of primarily emergency room visits approximately one to two weeks following 12 and 18 month vaccination. Future studies should examine whether these events could be predicted or prevented.

  17. Climate change and compensation

    DEFF Research Database (Denmark)

    Jensen, Karsten Klint; Flanagan, Tine Bech

    2013-01-01

    This paper presents a case for compensation of actual harm from climate change in the poorest countries. First, it is shown that climate change threatens to reverse the fight to eradicate poverty. Secondly, it is shown how the problems raised in the literature for compensation to some extent...... climate change. The first argument appeals to the principle that if it is an injustice to cause risk of incurring harm in the future, then it is also an injustice to cause a similar harm now. The second argument appeals to the principle that if there is moral reason to reduce the risk of specific harms...

  18. 基于生态地租的生态环境补偿理论建构及应用%Theory Construction and Its Application to Ecological Environment Compensation Based on Ecological Land Rent

    Institute of Scientific and Technical Information of China (English)

    龙开胜; 陈利根

    2012-01-01

    生态环境补偿是自然资源和生态管理领域亟待解决的问题。以“资源稀缺-生态地租-生态环境补偿”为逻辑主线,通过阐述生态地租Ⅰ和生态地租Ⅱ的形成过程,并以生态地租分配为依据,相应地将生态环境补偿分为反映生态资源消耗的生态环境补偿Ⅰ和反映生产效率改善的生态环境补偿Ⅱ两部分,从而构建基于生态地租的生态环境补偿理论框架,提出生态环境补偿的新思路。结合生态足迹数据及投入产出表,测算得到中国1997--2007年每年经济生产中应支付的生态环境补偿Ⅰ的总额由2781×108元增加到9900×108元,生态环境补偿Ⅱ的总额由26318×108元增加到68262×108元。今后,我国只有支付足额的生态环境补偿费用用于生态环境治理和激励生态环境保护贡献者,才能确保生态资源可持续利用。在此基础上,分析了实现生态环境补偿Ⅰ和生态环境补偿Ⅱ的相关途径。%Ecological environment compensation is an urgent problem need to be resolved in the field of natural resource and ecological management. As a new idea, ecological land rent has en- riched the methodology and theory of ecological environment compensation. Essentially, ecologi- cal land rent is excessive profits generated from scarcity of ecological resources, and the profits be used to pay for ecological environment compensation wouldn' t decrease the necessary income of social producers. So, it is a feasible way to perfect the theory and practice of ecological environ- ment compensation based on ecological land rent. Taking "resource scarcity- ecological land rent ecological environment compensation" as logic route, discussing the formation process of ecological land rent Ⅰ and ecological land rent Ⅱ , and according to allocation of ecological land rent, this paper distinguished ecological environment compensation Ⅰ related to ecological resource consumption from

  19. Tracking control of shape-memory-alloy actuators based on self-sensing feedback and inverse hysteresis compensation.

    Science.gov (United States)

    Liu, Shu-Hung; Huang, Tse-Shih; Yen, Jia-Yush

    2010-01-01

    Shape memory alloys (SMAs) offer a high power-to-weight ratio, large recovery strain, and low driving voltages, and have thus attracted considerable research attention. The difficulty of controlling SMA actuators arises from their highly nonlinear hysteresis and temperature dependence. This paper describes a combination of self-sensing and model-based control, where the model includes both the major and minor hysteresis loops as well as the thermodynamics effects. The self-sensing algorithm uses only the power width modulation (PWM) signal and requires no heavy equipment. The method can achieve high-accuracy servo control and is especially suitable for miniaturized applications.

  20. Tracking Control of Shape-Memory-Alloy Actuators Based on Self-Sensing Feedback and Inverse Hysteresis Compensation

    Directory of Open Access Journals (Sweden)

    Shu-Hung Liu

    2009-12-01

    Full Text Available Shape memory alloys (SMAs offer a high power-to-weight ratio, large recovery strain, and low driving voltages, and have thus attracted considerable research attention. The difficulty of controlling SMA actuators arises from their highly nonlinear hysteresis and temperature dependence. This paper describes a combination of self-sensing and model-based control, where the model includes both the major and minor hysteresis loops as well as the thermodynamics effects. The self-sensing algorithm uses only the power width modulation (PWM signal and requires no heavy equipment. The method can achieve high-accuracy servo control and is especially suitable for miniaturized applications.

  1. Malvinas: a proposal towards a viable solution, based on the idea of economic compensation to its inhabitants

    OpenAIRE

    1994-01-01

    El autor se propone los siguientes objetivos: 1) Examinar la viabilidad de la idea de una compensación económica a los habitantes de las Islas Malvinas como parte de una posible solución al conflicto en torno a la soberanía del archipiélago. 2) Establecer los puntos que deberían ser tenidos en cuenta en una eventual propuesta argentina de solución al conflicto que, tomando como base las sugerencias de los artículos del economista inglés Alan Walters, resulte viable y acorde con nuestros inter...

  2. Artificial Inductance Concept to Compensate Nonlinear Inductance Effects in the Back EMF-Based Sensorless Control Method for PMSM

    DEFF Research Database (Denmark)

    Lu, Kaiyuan; Lei, Xiao; Blaabjerg, Frede

    2013-01-01

    The back EMF-based sensorless control method is very popular for permanent magnet synchronous machines (PMSMs) in the medium- to high-speed operation range due to its simple structure. In this speed range, the accuracy of the estimated position is mainly affected by the inductance, which varies...... on the estimated position error, and gives a deep insight into this problem. It also provides a simple approach to achieve a globally minimized position error. A proper choice of the artificial machine inductance may reduce the maximum position error by 50% without considering the actual inductance variation...

  3. Graft function based on two hours peak level monitoring of cyclosporine A during the first six months of renal transplantation.

    Science.gov (United States)

    Hami, Maryam; Naghibi, Massih; Mojahedi, Mohammad Javad; Sharifipour, Farzaneh; Shakeri, Mohammad Taghi

    2012-11-01

    Inadequate cyclosporine blood levels may cause acute rejection in transplanted renal graft, and its increase is accompanied with graft toxicity. Cyclosporine has variable bioavailability and pharmacokinetics among patients at different times after transplantation. In this study, we compared the effects of cyclosporine blood levels (trough versus 2-hour peak, C2) on renal graft function during the first six months after transplantation in order to find better methods for drug levels assessment in our patients. We studied 50 patients who received grafts at Mashhad transplant centers from October 2006 to May 2007. Drug levels were monitored seven times during the study; in each assessment, more than 80% of the patients did not reach the therapeutic C2 levels. There was no significant correlation between age, sex, times of transplantation and acute rejection with drug C2 levels. There was no difference between graft function in patients with therapeutic C2 level and those with inadequate C2 levels. However, we found a significant correlation between trough levels and acute rejection (P transplantation was the drug dosage significantly higher in patients with therapeutic C2 level than that in other patients (P >0.05). Apparently, peak levels were not a suitable method in drug monitoring in our patients, or peak levels might have occurred at a different time (like 1.5 or 3 or 4 h after ingestion of the drug) in our population. Based on this study, trough level may be a better method of evaluation of cyclosporine effects on renal allografts than 2-h peak levels in our patients.

  4. EEPN and CD study for coherent optical nPSK and nQAM systems with RF pilot based phase noise compensation.

    Science.gov (United States)

    Jacobsen, Gunnar; Xu, Tianhua; Popov, Sergei; Li, Jie; Friberg, Ari T; Zhang, Yimo

    2012-04-09

    A radio frequency (RF) carrier can be used to mitigate the phase noise impact in n-level PSK and QAM systems. The systems performance is influenced by the use of an RF pilot carrier to accomplish phase noise compensation through complex multiplication in combination with discrete filters to compensate for the chromatic dispersion (CD). We perform a detailed study comparing two filters for the CD compensation namely the fixed frequency domain equalizer (FDE) filter and the adaptive least-mean-square (LMS) filter. The study provides important novel physical insight into the equalization enhanced phase noise (EEPN) influence on the system bit-error-rate (BER) versus optical signal-to-noise-ratio (OSNR) performance. Important results of the analysis are that the FDE filter position relative to the RF carrier phase noise compensation module provides a possibility for choosing whether the EEPN from the Tx or the LO laser influences the system quality. The LMS filter works very inefficiently when placed prior to the RF phase noise compensation stage of the Rx whereas it works much more efficiently and gives almost the same performance as the FDE filter when placed after the RF phase noise compensation stage.

  5. A new compensation current real-time computing method for power active filter based on double linear construction algorithm

    Institute of Scientific and Technical Information of China (English)

    LI; Zicheng; SUN; Yukun

    2006-01-01

    Considering the detection principle that "when load current is periodic current, the integral in a cycle for absolute value of load current subtracting fundamental active current is the least", harmonic current real-time detection methods for power active filter are proposed based on direct computation, simple iterative algorithm and optimal iterative algorithm. According to the direct computation method, the amplitude of the fundamental active current can be accurately calculated when load current is placed in stable state. The simple iterative algorithm and the optimal iterative algorithm provide an idea about judging the state of load current. On the basis of the direct computation method, the simple iterative algorithm, the optimal iterative algorithm and precise definition of the basic concepts such as the true amplitude of the fundamental active current when load current is placed in varying state, etc., the double linear construction idea is proposed in which the amplitude of the fundamental active current at the moment of the sample is accurately calculated by using the first linear construction and the condition which disposes the next sample is created by using the second linear construction. On the basis of the double linear construction idea, a harmonic current real-time detection method for power active filter is proposed based on the double linear construction algorithm. This method has the characteristics of small computing quantity, fine real-time performance, being capable of accurately calculating the amplitude of the fundamental active current and so on.

  6. A novel hybrid plasmonic waveguide with loss compensation via electrically pumped gain medium based on silicon platform

    Science.gov (United States)

    Zhu, Ning

    2013-01-01

    In this paper we propose and study a new hybrid plasmonic waveguide structure with gain medium. The structure is based on silicon platform with gain medium to be III-V material, which can be electrically pumped. The whole structure can be realized through the bonding technique. An adhesive polymer layer adopted in the bonding process acts as the low refractive index layer here in the hybrid plasmonic waveguide. Further simulation with gain presented shows that a moderate gain coefficient of 891 cm-1 is required for lossless propagation while keeping subwavelength modal size, especially in the lateral direction which is important for high density integration. Considering the fabrication compatibility, this new SPP structure would be highly favorable in the silicon photonics.

  7. A Face Detection Method for Illumination Compensation Based on Adaboost%基于A daboos t的人脸光照补偿方法

    Institute of Scientific and Technical Information of China (English)

    李雪源; 袁晨; 姜代红

    2014-01-01

    Traditional Adaboost face detection algorithm uneven illumination image detection rate decreased problem ,we propose a face detection method based on Adaboost algorithm for illumination compensation .Details of the Adaboost face detection algorithm processing and histogram equalization principle and Adaboost algorithm and histogram equalization combined to achieve face detection .Test results show that this method compared with conventional Adaboost face detec-tion method to detect the speed difference is not big ,but uneven illumination image face detection accuracy and false detec-tion rate has very good results .%针对传统Adaboost人脸检测算法中光照不均匀、图像检测正确率低的问题,提出一种基于Adaboost算法的人脸光照补偿检测方法。介绍Adaboost人脸检测算法的处理流程以及直方图均衡化原理,并将Adaboost算法和直方图均衡化相结合,实现人脸检测。检测结果表明,与传统的Adaboost人脸检测方法相比,新方法对于光照不均匀图像的人脸检测有很好的效果。

  8. Correction for scatter and septal penetration using convolution subtraction methods and model-based compensation in {sup 123}I brain SPECT imaging-a Monte Carlo study

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, Anne [Department of Radiation Sciences, Radiation Physics, Umeaa University, SE-901 87 Umeaa (Sweden); Ljungberg, Michael [Medical Radiation Physics, Department of Clinical Sciences, Lund, Lund University, SE-221 85 Lund (Sweden); Mo, Susanna Jakobson [Department of Radiation Sciences, Diagnostic Radiology, Umeaa University, SE-901 87 Umeaa (Sweden); Riklund, Katrine [Department of Radiation Sciences, Diagnostic Radiology, Umeaa University, SE-901 87 Umeaa (Sweden); Johansson, Lennart [Department of Radiation Sciences, Radiation Physics, Umeaa University, SE-901 87 Umeaa (Sweden)

    2006-11-21

    Scatter and septal penetration deteriorate contrast and quantitative accuracy in single photon emission computed tomography (SPECT). In this study four different correction techniques for scatter and septal penetration are evaluated for {sup 123}I brain SPECT. One of the methods is a form of model-based compensation which uses the effective source scatter estimation (ESSE) for modelling scatter, and collimator-detector response (CDR) including both geometric and penetration components. The other methods, which operate on the 2D projection images, are convolution scatter subtraction (CSS) and two versions of transmission dependent convolution subtraction (TDCS), one of them proposed by us. This method uses CSS for correction for septal penetration, with a separate kernel, and TDCS for scatter correction. The corrections are evaluated for a dopamine transporter (DAT) study and a study of the regional cerebral blood flow (rCBF), performed with {sup 123}I. The images are produced using a recently developed Monte Carlo collimator routine added to the program SIMIND which can include interactions in the collimator. The results show that the method included in the iterative reconstruction is preferable to the other methods and that the new TDCS version gives better results compared with the other 2D methods.

  9. Correction for scatter and septal penetration using convolution subtraction methods and model-based compensation in 123I brain SPECT imaging-a Monte Carlo study.

    Science.gov (United States)

    Larsson, Anne; Ljungberg, Michael; Mo, Susanna Jakobson; Riklund, Katrine; Johansson, Lennart

    2006-11-21

    Scatter and septal penetration deteriorate contrast and quantitative accuracy in single photon emission computed tomography (SPECT). In this study four different correction techniques for scatter and septal penetration are evaluated for 123I brain SPECT. One of the methods is a form of model-based compensation which uses the effective source scatter estimation (ESSE) for modelling scatter, and collimator-detector response (CDR) including both geometric and penetration components. The other methods, which operate on the 2D projection images, are convolution scatter subtraction (CSS) and two versions of transmission dependent convolution subtraction (TDCS), one of them proposed by us. This method uses CSS for correction for septal penetration, with a separate kernel, and TDCS for scatter correction. The corrections are evaluated for a dopamine transporter (DAT) study and a study of the regional cerebral blood flow (rCBF), performed with 123I. The images are produced using a recently developed Monte Carlo collimator routine added to the program SIMIND which can include interactions in the collimator. The results show that the method included in the iterative reconstruction is preferable to the other methods and that the new TDCS version gives better results compared with the other 2D methods.

  10. Correction for scatter and septal penetration using convolution subtraction methods and model-based compensation in 123I brain SPECT imaging—a Monte Carlo study

    Science.gov (United States)

    Larsson, Anne; Ljungberg, Michael; Jakobson Mo, Susanna; Riklund, Katrine; Johansson, Lennart

    2006-11-01

    Scatter and septal penetration deteriorate contrast and quantitative accuracy in single photon emission computed tomography (SPECT). In this study four different correction techniques for scatter and septal penetration are evaluated for 123I brain SPECT. One of the methods is a form of model-based compensation which uses the effective source scatter estimation (ESSE) for modelling scatter, and collimator-detector response (CDR) including both geometric and penetration components. The other methods, which operate on the 2D projection images, are convolution scatter subtraction (CSS) and two versions of transmission dependent convolution subtraction (TDCS), one of them proposed by us. This method uses CSS for correction for septal penetration, with a separate kernel, and TDCS for scatter correction. The corrections are evaluated for a dopamine transporter (DAT) study and a study of the regional cerebral blood flow (rCBF), performed with 123I. The images are produced using a recently developed Monte Carlo collimator routine added to the program SIMIND which can include interactions in the collimator. The results show that the method included in the iterative reconstruction is preferable to the other methods and that the new TDCS version gives better results compared with the other 2D methods.

  11. Rehabilitation Utilization following a Work-Related Traumatic Brain Injury: A Sex-Based Examination of Workers' Compensation Claims in Victoria, Australia.

    Directory of Open Access Journals (Sweden)

    E Niki Guerriero

    Full Text Available To report on and examine differences in the use of four types of rehabilitation services (occupational therapy, physiotherapy, psychology, and speech therapy by men and women following a work-related traumatic brain injury in Victoria, Australia; and to examine the importance of demographic, need, work-related and geographic factors in explaining these differences.A retrospective cohort design was used to analyze 1786 work-related traumatic brain injury workers' compensation claims lodged between 2004 and 2012 in Victoria, Australia. ZINB regressions were conducted for each type of rehabilitation service to examine the relationship between sex and rehabilitation use. Covariates included demographic, need-related, work-related, and geographic factors.Out of all claims (63% male, 37% female, 13% used occupational therapy, 23% used physiotherapy, 9% used psychology, and 2% used speech therapy at least once during the first year of service utilization. After controlling for demographic, need-related, work-related, and geographic factors, women were more likely to use physiotherapy compared to men. Men and women were equally likely to use occupational therapy and psychology services. The number of visits in the first year for each type of service did not differ between male and female users.Our findings support a sex-based approach to studying rehabilitation utilization in work-related populations. Future research is needed to examine other factors associated with rehabilitation utilization and to determine the implications of different rehabilitation utilization patterns on health and return-to-work outcomes.

  12. 深水勘察船基盘被动升沉补偿系统的设计研究%Passive heave compensation system for base plate used in deep-water exploration ship

    Institute of Scientific and Technical Information of China (English)

    羊衍贵; 陆敏恂; 谌志新; 徐志强; 张海波

    2013-01-01

    在深水勘察船升沉运动时,为使牵引基盘钢丝绳的拉力保持在一定的范围,设计了基盘被动升沉补偿系统.介绍了基盘被动升沉补偿系统的方案和工作原理,建立了基盘被动升沉补偿系统的数学模型,分析了钢丝绳对分析部件的拉力.对补偿系统中的滑轮组倍率、液压缸直径、液压缸行程和蓄能器总容积这4个主参数进行了分析设计,并分析了补偿系统中钢丝绳对基盘的拉力.最后针对具体的勘察船升沉运动和作业水深的设计条件以及钢丝绳对基盘的拉力范围的设计要求,通过对补偿系统中的一些设计参数的取值,对补偿系统中的主参数进行了设计计算,并对设计的补偿系统中钢丝绳对基盘的拉力进行了仿真.仿真结果表明,钢丝绳对基盘的拉力达到了设计要求.这为相关设计人员对基盘被动升沉补偿系统的设计提供了理论指导.%This paper focused on the passive heave compensation system for base plate used in the deep-water exploration ship. The passive heave compensation system for base plate was utilized to keep the tension in the wire rope within certain range when the deep-water exploration ship was heaving with the sea wave. The scheme and the working principle of passive heave compensation system for base plate were presented. The mathematic models on the passive heave compensation system were constructed. The tension of the wire rope pulling the study unit was analyzed. The main parameters including the ratio value of the pulley group, the diameter of the compensation cylinder, the stroke of the compensation cylinder and the total volume of the accumulator in the passive heave compensation system were analyzed and expressed. Finally according to the design conditions of the specific heave motion of the deep-water exploration ship, the specific operation water depth and design requirements of the tension of the wire rope pulling base plate in the passive

  13. Three-phase Four-wire Unbalanced Current Compensation Based on Steinmetz Theory%基于Steinmetz理论的三相四线制不平衡电流补偿

    Institute of Scientific and Technical Information of China (English)

    王江彬; 田铭兴; 陈敏; 赵远鑫

    2016-01-01

    由于零序分量的存在,三相四线制电路的不平衡补偿问题较三相三线制电路更复杂。该文基于Steinmetz理论的对称分量分析法考虑三相三线制系统负荷的平衡化补偿思路给出了三相四线制系统负荷不平衡电流的补偿方法,并给出3种约束方程下的补偿电纳模型。在三相四线制系统中,在已找到的3种约束方程条件下,对Y型联接的负荷进行零、负序电流补偿,并使系统功率因数提高到1。最后通过Matlab仿真表明,所提补偿理论不仅能实现不平衡电流的平衡化,还能使系统总功率因数接近于1,证明了所提补偿理论的正确性。%Because of the existence of zero sequence components,the unbalanced compensation of three-phase four-wire system is more complicated than that of three-phase three-wire system. The compensation method of symmetrical component analysis method based on Steinmetz theory in three-phase three-wire system load balancing compensation is considered in the three-phase four-wire system unbalanced load current compensation. Moreover,the compensation mod⁃el of three kinds of constraint equations is given. In the three-phase four-wire system with the three above constraint equations,attempts are made to compensate the zero sequence and negative sequence current for star-connected load, and increase the system power factor to 1. Finally,the Matlab simulation results show that the proposed compensation theory can not only keep the unbalanced current balanced,but also make the power factor of total system be equal to 1 approximately,which proves the correctness of the proposed compensation theory.

  14. Simulation Research on Semi-active Heave Compensation System Based on AMESim Software%基于AMESim的半主动式升沉补偿系统仿真研究

    Institute of Scientific and Technical Information of China (English)

    刘茹; 徐涛

    2016-01-01

    为进一步研究半主动式升沉补偿的补偿工作机制,在对半主动式升沉补偿装置补偿原理分析的基础上,对装置中的气液储能器和主动补偿缸进行了力学分析和流量连续性分析,并基于AMESim软件对补偿系统进行建模和仿真分析.结果表明:补偿过程中大钩位移随时间变化范围较小,处于小幅值正弦波动范围内,系统能耗曲线近似呈线性上升趋势以及气液储能器压力曲线变化整体趋于平稳.该系统仿真结果能为半主动式升沉补偿装置的设计改进和技术发展提供参考,进一步提高系统的补偿效率和降低能耗.%Abatract: In order to further study the compensation mechanism of semi-active heave compensation, based on the analysis of the compensation principle of semi-active heave compensation device, the analyses of mechanics and flow continuity of gas-liquid storage devices and active compensation cylinder was carried out. The AMESim software was accepted for the modeling and simulation analysis. The result shows that the variation range of compensation process of large hook displacement is in a small amplitude of sine wave when the time changes. The system energy consumption curve is approximate to linear upward trend and the pressure curve of gas liquid accu-mulator overall tends to leveled off. The system simulation results of semi-active heave compensation device can be used as the reference for improving the design and developing technology of the system of compensation efficiency and reducing energy consumption.

  15. A 2.4 GHz high-linearity low-phase-noise CMOS LC-VCO based on capacitance compensation

    Energy Technology Data Exchange (ETDEWEB)

    Li Zhenrong; Zhuang Yiqi; Li Bing; Jin Gang; Jin Zhao, E-mail: allen_lzr@126.co [Key Laboratory of the Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi' an 710071 (China)

    2010-07-15

    A 2.4 GHz high-linearity low-phase-noise cross-coupled CMOS LC voltage-controlled oscillator (VCO) is implemented in standard 0.18-{mu}m CMOS technology. An equalization structure for tuning sensitivity base on the three-stage distributed biased switched-varactor bank and the differential switched-capacitor bank is adopted to reduce the variations of the VCO gain, achieve high linearity, and optimize the phase-noise performance. Compared to the conventional VCO, the proposed VCO has more constant gain over the entire tuning range. The tuning range is about 18.7% from 2.23 to 2.69 GHz, and the phase noise is -95 dBc/Hz at 100-kHz offset and -117 dBc/Hz at 1-MHz offset from the carrier frequency of 2.42 GHz. The power dissipation is 2.1 mW from a 1.8 V power supply. The active area of this VCO is 500 x 810 {mu}m{sup 2}.

  16. Respiratory motion compensation for simultaneous PET/MR based on a 3D-2D registration of strongly undersampled radial MR data: a simulation study

    Science.gov (United States)

    Rank, Christopher M.; Heußer, Thorsten; Flach, Barbara; Brehm, Marcus; Kachelrieß, Marc

    2015-03-01

    We propose a new method for PET/MR respiratory motion compensation, which is based on a 3D-2D registration of strongly undersampled MR data and a) runs in parallel with the PET acquisition, b) can be interlaced with clinical MR sequences, and c) requires less than one minute of the total MR acquisition time per bed position. In our simulation study, we applied a 3D encoded radial stack-of-stars sampling scheme with 160 radial spokes per slice and an acquisition time of 38 s. Gated 4D MR images were reconstructed using a 4D iterative reconstruction algorithm. Based on these images, motion vector fields were estimated using our newly-developed 3D-2D registration framework. A 4D PET volume of a patient with eight hot lesions in the lungs and upper abdomen was simulated and MoCo 4D PET images were reconstructed based on the motion vector fields derived from MR. For evaluation, average SUVmean values of the artificial lesions were determined for a 3D, a gated 4D, a MoCo 4D and a reference (with ten-fold measurement time) gated 4D reconstruction. Compared to the reference, 3D reconstructions yielded an underestimation of SUVmean values due to motion blurring. In contrast, gated 4D reconstructions showed the highest variation of SUVmean due to low statistics. MoCo 4D reconstructions were only slightly affected by these two sources of uncertainty resulting in a significant visual and quantitative improvement in terms of SUVmean values. Whereas temporal resolution was comparable to the gated 4D images, signal-to-noise ratio and contrast-to-noise ratio were close to the 3D reconstructions.

  17. Modeling and Prediction of Monthly Total Ozone Concentrations by Use of an Artificial Neural Network Based on Principal Component Analysis

    Science.gov (United States)

    Chattopadhyay, Surajit; Chattopadhyay, Goutami

    2012-10-01

    In the work discussed in this paper we considered total ozone time series over Kolkata (22°34'10.92″N, 88°22'10.92″E), an urban area in eastern India. Using cloud cover, average temperature, and rainfall as the predictors, we developed an artificial neural network, in the form of a multilayer perceptron with sigmoid non-linearity, for prediction of monthly total ozone concentrations from values of the predictors in previous months. We also estimated total ozone from values of the predictors in the same month. Before development of the neural network model we removed multicollinearity by means of principal component analysis. On the basis of the variables extracted by principal component analysis, we developed three artificial neural network models. By rigorous statistical assessment it was found that cloud cover and rainfall can act as good predictors for monthly total ozone when they are considered as the set of input variables for the neural network model constructed in the form of a multilayer perceptron. In general, the artificial neural network has good potential for predicting and estimating monthly total ozone on the basis of the meteorological predictors. It was further observed that during pre-monsoon and winter seasons, the proposed models perform better than during and after the monsoon.

  18. A compensation index for multiattribute decision strategies.

    Science.gov (United States)

    Koele, P; Westenberg, M R

    1995-09-01

    In multiattribute decision problems, the subject has to evaluate a number of alternatives with given values on a number of attributes, in order to arrive at some conclusion about the attractiveness or utility of these alternatives. The information processing procedure leading to a conclusion is called adecision strategy, and one of the main research topics in multiattribute decision research has been the extent to which these strategies follow compensatory principles. Judges are said to follow compensatory strategies when low values on some attributes are compensated for by high values on other attributes. In process tracing studies using the information board technique, descriptions of decision strategies are usually based on three indices of the information search process:variability of search,search pattern (Payne, 1976), anddepth of search. Variability of search, defined as the standard deviation of the proportion of information searched per alternative, is considered to give an indication of the degree of compensation of a decision strategy, compensation being smaller as variability increases. In this article, we propose an alternative way for establishing the degree of compensation of decision strategies in information board studies. We argue that the degree of compensation depends on both variability of searchand depth of search (the proportion of information searched), and that a valid compensation index has to be a multiplicative function of these two indices.

  19. Co-phased Traction Power Supply System Based on Hybrid Compensation%基于混合补偿的同相牵引供电系统

    Institute of Scientific and Technical Information of China (English)

    周福林; 李群湛; 邱大强

    2012-01-01

    为解决异相牵引供电方式存在的电能质量和电力机车过分相问题,将有源补偿和无源对称补偿技术相结合,提出基于平衡变压器接线方式的混合式同相牵引供电系统结构.文中给出混合式同相供电的统一补偿理论、无源补偿系统的无源元件参数计算方法、有源补偿的控制策略、无源和有源补偿的协调控制策略.最后,以采用YNvd接线方式的平衡变压器为例,采用MATLAB软件仿真验证该系统方案和控制策略的正确性.%In order to control power quality and cancel neutral sections in out-phase power supply of existing e-lectrical railways, the new co-phased traction power supply system construction was presented on the basis of the balanced transformer, and active compensation and passive compensation technology. The theory of unified compensation, the calculating method of passive compensation parameters, the active compensation control strategy and the coordinated control strategy of active compensation and passive compensation were given for the co-phased power supply. Simulation by MATLAB was made with the Ynvd connection-mode transformer. The results verify the correctness of the presented system scheme and control strategy.

  20. New EMA report on paliperidone 3-month injections: taking clinical and policy decisions without an adequate evidence base.

    Science.gov (United States)

    Ostuzzi, G; Papola, D; Gastaldon, C; Barbui, C

    2016-12-22

    Three-month long-acting paliperidone is a new, recently marketed, formulation of paliperidone, characterised by the longest available dosing interval among long-acting antipsychotics. The clinical profile of 3-month long-acting paliperidone was recently summarised by the European Medicines Agency (EMA) in a public assessment report, released in April 2016. In this commentary, the main strengths and limitations of the EMA assessment report were appraised and discussed, in order to highlight possible implications for clinical practice, future research and regulatory practices for drug approval.

  1. Dose-response effects of aerobic exercise on energy compensation in postmenopausal women: combined results from two randomized controlled trials.

    Science.gov (United States)

    McNeil, J; Brenner, D R; Courneya, K S; Friedenreich, C M

    2017-08-01

    Despite the clear health benefits of exercise, exercised-induced weight loss is often less than expected. The term 'exercise energy compensation' is used to define the amount of weight loss below what is expected for the amount of exercise energy expenditure. We examined the dose-response effects of exercise volume on energy compensation in postmenopausal women. Data from Alberta Physical Activity and Breast Cancer Prevention (ALPHA) and Breast Cancer and Exercise Trial in Alberta (BETA) were combined for the present analysis. The ALPHA and BETA trials were two-centred, two-armed, 12-month randomized controlled trials. The ALPHA trial included 160 participants randomized to 225 min per week of aerobic exercise, and the BETA trial randomized 200 participants to each 150 and 300 min per week of aerobic exercise. All participants were aged 50-74 years, moderately inactive (compensation was based on changes in body composition (dual-energy X-ray absorptiometry scan) and estimated exercise energy expenditure from completed exercise volume. Associations between Δenergy intake, ΔVO2peak and Δphysical activity time with energy compensation were assessed. No differences in energy compensation were noted between interventions. However, there were large inter-individual differences in energy compensation between participants; 9.4% experienced body composition changes that were greater than expected based on exercise energy expenditure, 64% experienced some degree of energy compensation and 26.6% experienced weight gain based on exercise energy expenditure. Increases in VO2peak were associated with reductions in energy compensation (β=-3.44 ml kg(-1) min(-1), 95% confidence interval for β=-4.71 to -2.17 ml kg(-1) min(-1); P=0.0001). Large inter-individual differences in energy compensation were noted, despite no differences between activity doses. In addition, increases in VO2peak were associated with lower energy compensation. Future studies are needed to

  2. 基于GIS与RS的退耕还林生态补偿金的确定%Determination of eco-compensation of sloping land conversion program based on GIS and RS

    Institute of Scientific and Technical Information of China (English)

    郭慧敏; 王武魁; 冯仲科

    2015-01-01

    Since the implementation of ecological compensation policy in China, micro difference of geographic location does not been considered basically, but the implementation of the "sweeping approach" national compensation policy is divided into north and south of the Yangtze River. In practical application, although it has the advantages of unified standard, it ignores the actual existence of many realistic factors, such as terrain, soil, climate in forest land. The gap between compensation and woodland fine operation and management is very big. The objective of this paper was to solve the problem of ecological compensation standard in different regions. Taking compensation configuration of the Sloping Land Conversion Program in Zhangjiakou area as the research object, remote sensing (RS), geographic information system (GIS) and other space technologies were applied, the method of qualitative and quantitative analysis was adopted, the analytic hierarchy process (AHP) was used to determine the factors affecting ecological compensation weight, and the space allocation model of ecological compensation was established in this research. The results showed that: 1) The AHP method and the spatial analysis technology of RS and GIS were integrated. The AHP was good at multi-factor comprehensive evaluation, and in the application process, the GIS software showed a greater advantage on the data expression space, the digital and graphics integration as a whole, and the data processing, analysis and management functions, which could objectively reflect the specific situation of the region. Overall, the method in this research provides a new way for the calculation of the ecological compensation standard of farmland. 2) Among affecting factors of ecological restoration compensation in the study area, the weights of natural factors, social factors, economic factors were 0.5279, 0.3325 and 0.1396, respectively. 3) Based on the total sum of annual payment for ecosystem services (PES

  3. Examination of Veterans Affairs disability compensation as a disincentive for employment in a population-based sample of Veterans under age 65.

    Science.gov (United States)

    Tsai, Jack; Rosenheck, Robert A

    2013-12-01

    Concerns that disability benefits may create disincentives for employment may be especially relevant for young American military veterans, particularly veterans of the recent wars in Iraq and Afghanistan who are facing a current economic recession and turning in large numbers to the Department of Veterans Affairs (VA) for disability compensation. This study describes the rate of employment and VA disability compensation among a nationally representative sample of veterans under the age of 65 and examines the association between levels of VA disability compensation and employment, adjusting for sociodemographics and health status. Data on a total of 4,787 veterans from the 2010 National Survey of Veterans were analyzed using multinomial logistic regressions to compare employed veterans with two groups that were not employed. Two-thirds of veterans under the age of 65 were employed, although only 36 % of veterans with a VA service-connected disability rating of 50 % or higher were employed. Veterans who received no VA disability compensation or who were service-connected 50 % or more were more likely to be unemployed and not looking for employment than veterans who were not service-connected or were service-connected less than 50 %, suggesting high but not all levels of VA disability compensation create disincentives for employment. Results were similar when analyses were limited to veterans who served in Iraq and Afghanistan. Education and vocational rehabilitation interventions, as well as economic work incentives, may be needed to maximize employment among veterans with disabilities.

  4. Compensating Large PMD by Four Free degrees in an OTDM System

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In this paper, by introducing a two-stages polarization mode dispersion (PMD) compensator after a optical fiber link with a large PMD, we compensated over 270ps first-order and 2000ps2 high-order PMD in a optical fiber link with super high PMD. Our experimental results shows that, the compensators based on the two-stages of compensator can be used to PMD compensation in a 20Gb/s OTDM system with 60 km high PMD fiber. Before compensation, 270ps DGD is became into max. 7ps after compensation. At simultane...

  5. VISUALIZATION ANALYSIS OF THEORY BASE AND RESEARCH HOT SPOTS OF DOMESTIC AND INTERNATIONAL ECOLOGICAL COMPENSATION%国内外生态补偿基础理论与研究热点的可视化分析

    Institute of Scientific and Technical Information of China (English)

    胡小飞; 傅春; 陈伏生; 廖志娟

    2012-01-01

    With the aggravation of the ecological and environmental problems faced by humanity,the ecological compensation has become a hot topic of widespread concerns amongst domestic and foreign scholars.In order to understand the advances of ecological compensation,we carries out statistical analysis about the time of its publication based on 929documents from Web of Science and the Chinese Social Science Citation Index(CSSCI) database on the subject of ecology compensation in the time period of 1998-2011,and analyzes co-citation of literary documents and keyword co-occurrence using the CiteSpace Ⅱ software.Meanwhile,the key scholarly documents are listed,and research topics of eco-compensation are briefly concluded using knowledge mapping visual tool.We found the number of ecological compensation paper presented the trend of fluctuation growth from 1998to 2011.Research on eco-compensation of carbon sinks and REDD in the context of global climate change,eco-compensation zones and evaluation on the implementation of ecological compensation,strengthening the ecological compensation standards of the wetlands,nature reserves,watersheds and other ecosystem,application of computer management software(such as GIS,SWAT,InVEST) would become the focus issues in the future research on eco-compensation.Our results also showed that the domestic scholars had made great progress in the theory of eco-compensation,and the practice researches in forests,watersheds,nature reserves and other areas were strengthened in recent years.%随着人类面临的生态环境问题加重,生态补偿已成为国内外学者广泛关注的热点问题。为清晰地了解国内外生态补偿的研究现状和未来发展,以Web of Science、中文社会科学引文索引(CSSCI)数据库中1998~2011年有关生态补偿的929篇文献为基础,应用CiteSpace Ⅱ软件分析了论文发表数量、文献共被引和关键词共现等特征,并以知识图谱可视化的方式,归纳了近年来

  6. 基于级联有源滤波器与静止无功补偿器的综合补偿控制方案%A Universal Compensation Control Scheme Based on Cascade Active Power Filter and Static Var Compensator

    Institute of Scientific and Technical Information of China (English)

    高聪哲; 姜新建; 李永东

    2012-01-01

    How to keep system stability and optimize var compensation capability is the key issue in the combined system based on cascade multilevel active power filter(CS-APF) and static var compensator(SVC).A universal control strategy is proposed for the combined system.For the SVC,a feed forward control for the compensation of positive sequence reactive component and negative sequence component of the load is adopted.The network susceptance(with no components of CS-APF) feedback control is applied to decrease the compensation error.For the CS-APF control,a feed forward control of harmonic compensation for thyristor control reactor(TCR) and the load is applied.The network harmonic current feedback control is applied to decrease the compensation error.The fixed capacitor(in SVC) current component is removed from the network current feedback control loop of CS-APF to improve the stability of the combined system.The var compensation capability of CS-APF is enabled to optimize the performance of SVC.Moreover,a novel pre-calculation method for the TCR harmonic current detection is proposed.According to the triggering angle of the thyristor in TCR and the network voltage phase,the harmonic current is constructed with no time delay.Finally,the simulation and experimental results show that: 1)the system stability is high without closed loop between the control of CS-APF and SVC;2)the real-time harmonic compensation of TCR is realized;3)the system responsibility is quick;and 4)the capability of var compensation of SVC is improved.%级联多电平有源滤波器(CS-APF)与静止无功补偿器(SVC)同时运行存在稳定性及无功补偿控制优化等问题。文中提出一种统一控制策略,结合SVC和CS-APF的功能特点,使SVC对负载正序无功分量及负序分量的补偿进行前馈控制和电网电纳(不包含CS-APF分量)反馈控制;CS-APF对晶闸管相控电抗器(TCR)与电网负载谐波的补偿进行前馈

  7. RELIABILITY OF LENTICULAR EXPANSION COMPENSATORS

    Directory of Open Access Journals (Sweden)

    Gabriel BURLACU,

    2011-11-01

    Full Text Available Axial lenticular compensators are made to take over the longitudinal heat expansion, shock , vibration and noise, made elastic connections for piping systems. In order to have a long life for installations it is necessary that all elements, including lenticular compensators, have a good reliability. This desire can be did by technology of manufactoring and assembly of compensators, the material for lenses and by maintenance.of compensator

  8. Deferred Compensation Becomes More Common

    Science.gov (United States)

    June, Audrey Williams

    2006-01-01

    A key part of the compensation package for some college and university presidents is money that they do not receive in their paychecks. Formally known as deferred compensation, such payments can take many forms, including supplemental retirement pay, severance pay, or even bonuses. With large institutions leading the way, deferred compensation has…

  9. Compensation for Occupational Cancer

    OpenAIRE

    Kim, Inah; Kim, Eun-A; Kim, Jae Young

    2014-01-01

    The legal scope and criteria for occupational cancer in Korea was out of date. The aim of this study was to review the current criteria for occupational cancer and amend the existent criteria on the basis of recent scientific evidence. The scientific evidence and the legal list of occupational cancer were analyzed to identify the causes of occupational cancer on a global scale. The relationship between compensated occupational cancer cases and carcinogen exposure in Korea was examined. The fa...

  10. Enhanced job performance: a new role for military compensation

    OpenAIRE

    2000-01-01

    This study concentrates on aspects of military and civilian compensation that motivate employees and provide incentives upon which job performance and productivity may depend. The study achieves its end by applying successful attributes of civilian compensation to military remuneration systems. Its main purpose is to judge whether military pay is structured toward a modern view of performance-based compensation and whether it is comparable to civilian pay. At issue is a military pay system th...

  11. Fringe Benefits Compensation of Real Estate Agents and Brokers

    OpenAIRE

    Daniel T. Winkler; W. Keener Hughen

    2012-01-01

    Fringe benefits compensation offered by employers has grown rapidly over the past 50 years. Research in this area has been primarily limited to hourly and salaried employees. This study examines employer-based fringe benefits compensation of real estate agents and brokers. A model is developed that jointly estimates the income, hours worked, and fringe benefits compensation. The findings indicate that fringe benefits increase according to hours worked and the sales professional¡¦s contributio...

  12. Luminescent systems based on the isolation of conjugated PI systems and edge charge compensation with polar molecules on a charged nanostructured surface

    Science.gov (United States)

    Ivanov, Ilia N.; Puretzky, Alexander A.; Zhao, Bin; Geohegan, David B.; Styers-Barnett, David J.; Hu, Hui

    2014-07-15

    A photoluminescent or electroluminescent system and method of making a non-luminescent nanostructured material into such a luminescent system is presented. The method of preparing the luminescent system, generally, comprises the steps of modifying the surface of a nanostructured material to create isolated regions to act as luminescent centers and to create a charge imbalance on the surface; applying more than one polar molecule to the charged surface of the nanostructured material; and orienting the polar molecules to compensate for the charge imbalance on the surface of the nanostructured material. The compensation of the surface charge imbalance by the polar molecules allows the isolated regions to exhibit luminescence.

  13. Design and implementation of adaptive slope compensation in current mode DC-DC converter

    Energy Technology Data Exchange (ETDEWEB)

    Guo Zhongjie; Wu Longsheng; Liu Youbao, E-mail: guozhongjie4213@126.com [Xi' an Microelectronic Technology Institute, Xi' an 710054 (China)

    2010-12-15

    To improve the compensation for the inherent instability in a current mode converter, the adaptive slope compensation, giving attention to the problems of the traditional compensation on compensation accuracy, loading capability and turning jitter, is presented. Based on the analysis of current loop, by detecting the input and output voltage, converting the adaptive slope compensation current, the compensation of the current loop is optimized successfully. It can not only improve the compensation accuracy but also eliminate the over compensation, the turning jitter and the poor loading capability in the reported slope compensation. A power supply chip with adaptive slope compensation has been fabricated in a 0.35 {mu}m CMOS process. The measurement results show that the chip starts up and operates steadily with the constant current limit under conditions of 5 V input voltage, from 10% to 100% duty cycle. (semiconductor integrated circuits)

  14. Understanding satellite-based monthly-to-seasonal reservoir outflow estimation as a function of hydrologic controls

    Science.gov (United States)

    Bonnema, Matthew; Sikder, Safat; Miao, Yabin; Chen, Xiaodong; Hossain, Faisal; Ara Pervin, Ismat; Mahbubur Rahman, S. M.; Lee, Hyongki

    2016-05-01

    Growing population and increased demand for water is causing an increase in dam and reservoir construction in developing nations. When rivers cross international boundaries, the downstream stakeholders often have little knowledge of upstream reservoir operation practices. Satellite remote sensing in the form of radar altimetry and multisensor precipitation products can be used as a practical way to provide downstream stakeholders with the fundamentally elusive upstream information on reservoir outflow needed to make important and proactive water management decisions. This study uses a mass balance approach of three hydrologic controls to estimate reservoir outflow from satellite data at monthly and annual time scales: precipitation-induced inflow, evaporation, and reservoir storage change. Furthermore, this study explores the importance of each of these hydrologic controls to the accuracy of outflow estimation. The hydrologic controls found to be unimportant could potentially be neglected from similar future studies. Two reservoirs were examined in contrasting regions of the world, the Hungry Horse Reservoir in a mountainous region in northwest U.S. and the Kaptai Reservoir in a low-lying, forested region of Bangladesh. It was found that this mass balance method estimated the annual outflow of both reservoirs with reasonable skill. The estimation of monthly outflow from both reservoirs was however less accurate. The Kaptai basin exhibited a shift in basin behavior resulting in variable accuracy across the 9 year study period. Monthly outflow estimation from Hungry Horse Reservoir was compounded by snow accumulation and melt processes, reflected by relatively low accuracy in summer and fall, when snow processes control runoff. Furthermore, it was found that the important hydrologic controls for reservoir outflow estimation at the monthly time scale differs between the two reservoirs, with precipitation-induced inflow being the most important control for the Kaptai

  15. Study of image motion compensation in spectral imaging system

    Science.gov (United States)

    Li, Zhijun; Chen, Xing Long

    2016-10-01

    In the spectral imaging system, random jitter and posture change of the aircraft generated random image motion, and flight of aircraft caused forward image motion. Both of image motion can cause image blur in a longer exposure time, which need for image motion compensation. Due to limited field of view of the optical system, limited size and weight, a stable FSM (Fast Steering Mirror) was used for random image motion compensation and a compensation FSM was used for forward image motion compensation. In the random image motion compensation, inertial sensors were used for measuring the random jitter and the posture change of the aircraft. As the advantages and disadvantages for the gyroscope and inclinometer, we used data fusion of the two sensors to complementary advantages with closed-loop mode filter data based on the frequency domain. In this way, we got high linearity, little drift, high bandwidth and little electrical noise inertial measurement sensors. On the other hand, the motion of the compensation mirror was broken down to the amount of displacement within the time required for each interrupt movement. Under strict timing control, macro forward image motion compensation was realized in the exposure time. The above image motion compensation methods were applied to actual spectral imaging systems, aerial experiment results show that image motion compensation obtained good results and met the remaining image motion compensation image error was not more than 1/3 pixel.

  16. The digital compensation technology system for automotive pressure sensor

    Science.gov (United States)

    Guo, Bin; Li, Quanling; Lu, Yi; Luo, Zai

    2011-05-01

    Piezoresistive pressure sensor be made of semiconductor silicon based on Piezoresistive phenomenon, has many characteristics. But since the temperature effect of semiconductor, the performance of silicon sensor is also changed by temperature, and the pressure sensor without temperature drift can not be produced at present. This paper briefly describe the principles of sensors, the function of pressure sensor and the various types of compensation method, design the detailed digital compensation program for automotive pressure sensor. Simulation-Digital mixed signal conditioning is used in this dissertation, adopt signal conditioning chip MAX1452. AVR singlechip ATMEGA128 and other apparatus; fulfill the design of digital pressure sensor hardware circuit and singlechip hardware circuit; simultaneously design the singlechip software; Digital pressure sensor hardware circuit is used to implementing the correction and compensation of sensor; singlechip hardware circuit is used to implementing to controll the correction and compensation of pressure sensor; singlechip software is used to implementing to fulfill compensation arithmetic. In the end, it implement to measure the output of sensor, and contrast to the data of non-compensation, the outcome indicates that the compensation precision of compensated sensor output is obviously better than non-compensation sensor, not only improving the compensation precision but also increasing the stabilization of pressure sensor.

  17. Managerial Stock Compensation and Risky Investment

    Directory of Open Access Journals (Sweden)

    Raluca Georgiana Nastasescu

    2009-06-01

    Full Text Available This study analyzes the relationship between the mix of CEO equity-based compensation, namely stock options and restricted stock, and firms' risky investment. In general, the theory suggests that long-term compensation aligns CEOs' and shareholders' interests by inducing the managers to undertake risky investment, which has a positive impact on longterm well-being of the firm. However, as my results show, it is important to distinguish between types of awards since they can have different effects on the riskiness of the firm. In this respect, I answer the question how are different types of stock based compensation related to the executives' determination to increase or not the intensity of the firm's risky investment? I find that awarding the CEOs preponderantly with stock options positively affects the firm's level of R&D investment. Conversely, a higher proportion of restricted stock in the CEO's compensation is related to lower investment in (risky R&D. The inverse relation of causality also holds. Firms that make intensive R&D investments are more likely to award their CEOs with more stock options relative to restricted stock. Overall, the results are consistent with the theoretical prediction, in that the managerial compensation scheme plays an important role in determining the level of R&D investment.

  18. The duration of gastrointestinal and joint symptoms after a large waterborne outbreak of gastroenteritis in Finland in 2007--a questionnaire-based 15-month follow-up study.

    Directory of Open Access Journals (Sweden)

    Janne Laine

    Full Text Available An extensive drinking water-associated gastroenteritis outbreak took place in the town of Nokia in Southern Finland in 2007. 53% of the exposed came down with gastroenteritis and 7% had arthritis-like symptoms (joint swelling, redness, warmth or pain in movement according to a population-based questionnaire study at 8 weeks after the incident. Campylobacter and norovirus were the main pathogens. A follow-up questionnaire study was carried out 15 months after the outbreak to evaluate the duration of gastrointestinal and joint symptoms. 323 residents of the original contaminated area were included. The response rate was 53%. Participants were inquired about having gastroenteritis during the outbreak and the duration of symptoms. Of those with gastroenteritis, 43% reported loose stools and abdominal pain or distension after the acute disease. The prevalence of symptoms declined promptly during the first 3 months but at 15 months, 11% reported continuing symptoms. 32% of the respondents with gastroenteritis reported subsequent arthritis-like symptoms. The disappearance of arthritis-like symptoms was more gradual and they levelled off only after 5 months. 19% showed symptoms at 15 months. Prolonged gastrointestinal symptoms correlated to prolonged arthritis-like symptoms. High proportion of respondents continued to have arthritis-like symptoms at 15 months after the epidemic. The gastrointestinal symptoms, instead, had declined to a low level.

  19. A community-based iron supplementation program, "Iron-Like Turkey", and the following prevalence of anemia among infants aged 12-23 months.

    Science.gov (United States)

    Yalçın, S Songül; Tezel, Başak; Yurdakök, Kadriye; Pekcan, Gülden; Ozbaş, Sema; Köksal, Eda; Tunç, Bahattin; Sahinli, Selvi; Altunsu, A Tanju; Köse, M Rifat; Buzgan, Turan; Akdağ, Recep

    2013-01-01

    During the second year of the "Iron-like Turkey" Project, in which all children aged 4-6 months in Turkey receive iron supplementation for 5 months, we aimed to assess the utilization of iron supplementation in the field, as well as the prevalence of anemia in healthy infants aged 12-23 months, while determining a variety of sociodemographic and nutritional factors for anemia in three of the 12 NUTS (Nomenclature of Territorial Units for Statistics) regions (regions with the highest, lowest and middle under-5 malnutrition levels). In a community-based, cross-sectional survey using a multi-staged, weighted, cluster-selected sample, children aged 12-23 months with birthweight ≥2500 g, no chronic illness, no history of blood disease, and from term and singleton pregnancy were enrolled; 1589 children met the criteria. The mean±SD age of children surveyed was 17.8±3.6 months. Of the parents, 72.4% claimed that their physician had recommended iron supplementation, and 68.8% had given supplementation to their children. Overall prevalence of anemia was 7.3%. Multivariate analysis revealed that the frequency of anemia decreased significantly in older infants, when supplementation was recommended by health providers, when an infant was breastfed longer than 6 months, and when the mother received iron supplementation during pregnancy. However, anemia prevalence increased when the infant received iron supplementation at a later age (³9 months), lived in a crowded family (³6 persons), and when the mother had a history of iron deficiency anemia. Anemic infants had significantly lower z scores of weight for age than non-anemic ones. This survey suggests that iron supplementation during pregnancy, initiation of iron supplementation in infants at 4-6 months of age, effective counseling on supplementation, subsequent compliance, support of breastfeeding, and effective training of health care personnel are effective strategies for prevention of anemia in the community.

  20. Formation of a quasi-neutral region in Schottky diodes based on semi-insulating GaAs and the influence of the compensation mechanism on the particle detector performance

    CERN Document Server

    Rogalla, M

    1999-01-01

    A model for the electric field distribution beneath the Schottky contact in semi-insulating (SI) GaAs particle detectors is developed. The model is based on a field-enhanced electron capture of the EL2-defect. The influence of the compensation mechanism in SI-GaAs on the field distribution, leakage current density and charge collection properties of the detectors will be discussed. The detailed understanding allows then a device optimization. (author)

  1. Acid-base status at birth, spontaneous motor behaviour at term and 3 months and neurodevelopmental outcome at age 4 years in full-term infants

    NARCIS (Netherlands)

    Wildschut, J; Feron, FJM; Hendriksen, JGM; van Hall, M; Gavilanes-Jiminez, DWD; Hadders-Algra, M; Vles, JSH

    2005-01-01

    Objective: The aim of the study was to assess the relationship between acid-base status and quality and quantity of General Movements (GMs) at birth and quality of GMs at age 3 months and motor, cognitive and behavioural functioning at the age of 4 years. Methods: From a cohort of 84 term children w

  2. Game-Based Cognitive-Behavioral Therapy (GB-CBT) Group Program for Children Who Have Experienced Sexual Abuse: A Three-Month Follow-Up Investigation

    Science.gov (United States)

    Springer, Craig; Misurell, Justin R.; Hiller, Atara

    2012-01-01

    This study examined the efficacy of a game-based cognitive-behavioral group therapy program for addressing problems typically found among elementary school-aged victims of child sexual abuse immediately after treatment and at three months following treatment. It was hypothesized that positive gains would be observed among the following domains:…

  3. Acid-base status at birth, spontaneous motor behaviour at term and 3 months and neurodevelopmental outcome at age 4 years in full-term infants

    NARCIS (Netherlands)

    Wildschut, J; Feron, FJM; Hendriksen, JGM; van Hall, M; Gavilanes-Jiminez, DWD; Hadders-Algra, M; Vles, JSH

    Objective: The aim of the study was to assess the relationship between acid-base status and quality and quantity of General Movements (GMs) at birth and quality of GMs at age 3 months and motor, cognitive and behavioural functioning at the age of 4 years. Methods: From a cohort of 84 term children

  4. Game-Based Cognitive-Behavioral Therapy (GB-CBT) Group Program for Children Who Have Experienced Sexual Abuse: A Three-Month Follow-Up Investigation

    Science.gov (United States)

    Springer, Craig; Misurell, Justin R.; Hiller, Atara

    2012-01-01

    This study examined the efficacy of a game-based cognitive-behavioral group therapy program for addressing problems typically found among elementary school-aged victims of child sexual abuse immediately after treatment and at three months following treatment. It was hypothesized that positive gains would be observed among the following domains:…

  5. Developmental outcomes among 18-month-old Malawians after a year of complementary feeding with lipid-based nutrient supplements or corn-soy flour

    Science.gov (United States)

    The major aim of this trial was to compare the development of 18-month-old infants who received complementary feeding for 1 year with either lipid-based nutrient supplements or micronutrient-fortified corn-soy porridge. Our secondary aim was to determine the socio-economic factors associated with de...

  6. Do interactions speak louder than words? Dialogic reading of an interactive tablet-based e-book with children between 16 months and three years of age

    DEFF Research Database (Denmark)

    Knoche, Hendrik; Rasmussen, Niklas Ammitzbøl; Boldreel, Kasper

    2014-01-01

    the effect of interactive elements on speech production of 12 children between the ages of 16 and 33 months when engaged in individual dialogic reading sessions with a tablet-based e-book. Interaction with interactive elements did not reduce the children’s responses to dialogic reading prompts. Spontaneous...

  7. All-optical and digital non-linear compensation algorithms in flex-coherent grouped and un-grouped contiguous spectrum based networks

    DEFF Research Database (Denmark)

    Asif, Rameez

    2016-01-01

    We have evaluated that in-line non-linear compensation schemes decrease the complexity of digital backward propagation and enhance the transmission performance of 40/112/224 Gbit/s mixed line rate network. Multiple bit rates, i.e. 40/112/224 Gbit/s and modulation formats (i.e. DP-QPSK and DP-16QA...

  8. Empirical Analysis on Farmers’ Willingness to Accept Compensation Whose Land is Expropriated——Based on Survey Analysis on Rural Households in 17 Provinces

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    According to the data of survey on farmers’ land right from Rural Development Institute (the USA),Renmin University of China and Michigan S ate University,this paper conducts empirical analysis on farmers’ willingness to accept compensation ho e land is expropriated and the related influencing factors by adopting Logistic model.The study indicates that the proportion of farmers’ non-agricultural income,the level of economic development in the region,participation right and right to vote,exert conspicuous impact on farmers’ satisfaction degr whose land is expropriated.In the provinces that are surveyed,most of the expropriated land is used for the public welfare project building,and in the current context of rapid urbanization,the conditions for defining public interests have not yet been put in place;the farmers in developed regions with more non-agricultural job opportunities express higher degree of satisfaction to the compensation for expropriated land;it is required to establish sound land expropriation compensation mechanism and bolster farmers’ participation right,so as to offer fair and reasonable compensation for the farmers whose land is expropriated.

  9. Assessment and Comparison of Homogeneity and Conformity Indexes in Step-and-Shoot and Compensator-Based Intensity Modulated Radiation Therapy (IMRT) and Three-Dimensional Conformal Radiation Therapy (3D CRT) in Prostate Cancer.

    Science.gov (United States)

    Salimi, Marzieh; Abi, Kaveh Shirani Tak; Nedaie, Hassan Ali; Hassani, Hossein; Gharaati, Hussain; Samei, Mahmood; Shahi, Rezgar; Zarei, Hamed

    2017-01-01

    Intensity modulated radiation therapy (IMRT) and three-dimensional conformal radiation therapy (3D CRT) are two treatment modalities in prostate cancer, which provide acceptable dose distribution in tumor region with sparing the surrounding normal tissues. IMRT is based on inverse planning optimization; in which, intensity of beams is modified by using multileaf collimators and also compensators with optimum shapes in step and shoot (SAS) and compensator-based method, respectively. In the recent study, some important parameters were compared in two IMRT and 3D CRT methods. Prescribed dose was 80 Gy for both IMRT procedures and 70 Gy for 3D CRT. Treatment plans of 15 prostate cancer candidates were compared to target the minimum dose, maximum dose, V 76 Gy (for IMRT plans) V 66.5 Gy (for 3D CRT), mean dose, conformity index (CI), and homogeneity index (HI). Dose conformity in compensators-based IMRT was better than SAS and 3D CRT. The same outcome was also achieved for homogeneity index. The target coverage was achieved 95% of prescribed dose to 95% of planning target volume (PTV) in 3D CRT and 95% of prescribed dose to 98% of PTV in IMRT methods. IMRT increases maximum dose of tumor region, improves CI and HI of target volume, and also reduces dose of organs at risks.

  10. The full moon as a synchronizer of circa-monthly biological rhythms: Chronobiologic perspectives based on multidisciplinary naturalistic research.

    Science.gov (United States)

    Reinberg, Alain; Smolensky, Michael H; Touitou, Yvan

    Biological rhythmicity is presumed to be an advantageous genetic adaptation of fitness and survival value resulting from evolution of life forms in an environment that varies predictably-in-time during the 24 h, month, and year. The 24 h light/dark cycle is the prime synchronizer of circadian periodicities, and its modulation over the course of the year, in terms of daytime photoperiod length, is a prime synchronizer of circannual periodicities. Circadian and circannual rhythms have been the major research focus of most scientists. Circa-monthly rhythms triggered or synchronized by the 29.5 day lunar cycle of nighttime light intensity, or specifically the light of the full moon, although explored in waterborne and certain other species, have received far less study, perhaps because of associations with ancient mythology and/or an attitude naturalistic studies are of lesser merit than ones that entail molecular mechanisms. In this editorial, we cite our recent discovery through multidisciplinary naturalistic investigation of a highly integrated circadian, circa-monthly, and circannual time structure, synchronized by the natural ambient nyctohemeral, lunar, and annual light cycles, of the Peruvian apple cactus (C. peruvianus) flowering and reproductive processes that occur in close temporal coordination with like rhythms of the honey bee as its pollinator. This finding led us to explore the preservation of this integrated biological time structure, synchronized and/or triggered by environmental light cues and cycles, in the reproduction of other species, including Homo sapiens, and how the artificial light environment of today in which humans reside may be negatively affecting human reproduction efficiency.

  11. Solution of Phase Compensation Problems for ISAR Imaging

    Institute of Scientific and Technical Information of China (English)

    QIUXiaohui; ZHAOYang; HENGWangChengAlice

    2005-01-01

    Solution of phase compensation for Inverse synthetic aperture radar (ISAR) imaging has been analyzed in classification, including maximum likelihoodbased phase compensation and minimum entropy-based phase compensation. Further, it is proved in paper that minimum entropy method actually is not an optimal solution since its extreme small value is only a local extremum. Also comparison between two type methods has been done for real ISAR data processing together with discussion on characteristics of phase compensation for those methods in this paper. Results show that minimum entropy method has better focusing than maximum likelihood method, however, it is with huge computation work.

  12. An Environment for Flexible Advanced Compensations of Web Service Transactions

    DEFF Research Database (Denmark)

    Schaefer, Michael; Dolog, Peter; Nejdl, Wolfgang

    2008-01-01

    recovery principles. We extend the existing Web service transaction coordination architecture and infrastructure in order to support flexible compensation operations. We use a contract-based approach, which allows the specification of permitted compensations at runtime. We introduce abstract service......Business to business integration has recently been performed by employing Web service environments. Moreover, such environments are being provided by major players on the technology markets. Those environments are based on open specifications for transaction coordination. When a failure...... in such an environment occurs, a compensation can be initiated to recover from the failure. However, current environments have only limited capabilities for compensations, and are usually based on backward recovery. In this article, we introduce an environment to deal with advanced compensations based on forward...

  13. 38 CFR 3.4 - Compensation.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Compensation. 3.4 Section..., Compensation, and Dependency and Indemnity Compensation General § 3.4 Compensation. (a) Compensation. This term...) Disability compensation. (1) Basic entitlement for a veteran exists if the veteran is disabled as the...

  14. 电子废弃物回收企业经济补偿机制的系统动力学研究%Analysis on Economic Compensation Mechanism of Electronic Waste Recycling Enterprise Based on System Dynamics

    Institute of Scientific and Technical Information of China (English)

    孙明波; 张世勋

    2012-01-01

    提出了利用系统动力学建模的方法来分析电子废弃物回收企业经济补偿机制,并依此对相关改革政策进行探讨.分析结果表明,此补偿机制涉及到生产商、消费者、政府等相关主体及相关政策,回收利用扶助资金、转化后的资源收益、财政征收的税费共同构成电子废弃物回收企业的经济补偿来源.改革政策的推行和完善应以经济补偿机制为基础并系统考量.最后,以广东省为例进行了实证研究.%System dynamics method was used to analyze the economic compensation mechanism of electronic waste recycling enterprise, and based on this, some reform policies were discussed. It showed that the model of electronic waste recycling enterprise' s economic compensation included producers, consumers, government and related policies. Recycling assisted fund, recycling resource income, taxes make up the economic compensation of electronic waste recycling enterprise together. The implementation and perfection of reform policies should be systematically designed and based on the e-conomic compensation mechanism. Finally, the result was tested by empirical research based on Guangdong province.

  15. A community-based caries control program for pre-school children using topical fluorides: 18-month results.

    Science.gov (United States)

    Lo, E C; Chu, C H; Lin, H C

    2001-12-01

    Dental caries in Chinese pre-school children is common, and restorative treatment is not readily available. This prospective controlled clinical trial investigated the effectiveness of topical fluoride applications in arresting dentin caries. We divided 375 children (aged 3-5 yrs) with carious upper anterior teeth into five groups. Children in the first and second groups received annual applications of silver diamine fluoride solution (44,800 ppm F). NaF varnish (22,600 ppm F) was applied every three months onto the lesions of children in the third and fourth groups. For children in the first and third groups, soft carious tissues were removed prior to fluoride application. The fifth group was the control. We followed 341 children for 18 months. The mean numbers of new caries surfaces in the five groups were 0.4, 0.4, 0.8, 0.6, and 1.2, respectively (p = 0.001). The respective mean numbers of arrested carious tooth surfaces were 2.8, 3.0, 1.7, 1.5, and 1.0 (p < 0.001).

  16. Sex-based comparison of limb segmentation in ostriches aged 14 months with and without tibiotarsal rotation : research note

    Directory of Open Access Journals (Sweden)

    R.G. Cooper

    2008-05-01

    Full Text Available The aim of this study was to propose equations to predict changes that occur over time in the angular position of the bones during motion and the angular velocity of the bones in forward motion as a consequence of tibiotarsal rotation (TTR in ostriches aged 14 months.Twenty-four normal 14-month-old ostriches (12 cocks and 12 hens and 20 birds with TTR (9 cocks and 11 hens were used in the study. Daily readings of temperature, relative humidity and rainfall, the lengths of the different segments of the legs and wings, the perpendicular height from the top of the torso to ground level and the length of the erect neck were recorded. Measurements of the degree of valgus deformity in the left foot were made where applicable. TTR hens and cocks were smaller in stature than normal birds. Comparing TTR hens and cocks, the toe, claw, humerus, perpendicular height and angle of rotation were larger in cocks, indicating a larger body in cocks. Hens were more severely affected by TTR. We suggest that the equations used in this study will assist in measuring movement of ostriches and how movement is compromised by overcrowding and TTR. Birds suffering from TTR may experience an increased degree of stress due to movement restrictions in confinement.

  17. Forest ecosystem services and eco-compensation mechanisms in China.

    Science.gov (United States)

    Deng, Hongbing; Zheng, Peng; Liu, Tianxing; Liu, Xin

    2011-12-01

    Forests are a major terrestrial ecosystem providing multiple ecosystem services. However, the importance of forests is frequently underestimated from an economic perspective because of the externalities and public good properties of these services. Forest eco-compensation is a transfer mechanism that serves to internalize the externalities of forest ecosystem services by compensating individuals or companies for the losses or costs resulting from the provision of these services. China's current forest eco-compensation system is centered mainly on noncommercial forest. The primary measures associated with ecosystem services are (1) a charge on destructive activities, such as indiscriminate logging, and (2) compensation for individual or local activities and investments in forest conservation. The Compensation Fund System for Forest Ecological Benefits was first listed in the Forest Law of the People's Republic of China in 1998. In 2004, the Central Government Financial Compensation Fund, an important source for the Compensation Fund for Forest Ecological Benefits, was formally established. To improve the forest eco-compensation system, it is crucial to design and establish compensation criteria for noncommercial forests. These criteria should take both theoretical and practical concerns into account, and they should be based on the quantitative valuation of ecosystem services. Although some initial headway has been made on this task, the implementation of an effective forest eco-compensation system in China still has deficiencies and still faces problems. Implementing classification-based and dynamic management for key noncommercial forests and establishing an eco-compensation mechanism with multiple funding sources in the market economy are the key measures needed to conquer these problems and improve the forest eco-compensation system and China's forestry development in sequence.

  18. Forest Ecosystem Services and Eco-Compensation Mechanisms in China

    Science.gov (United States)

    Deng, Hongbing; Zheng, Peng; Liu, Tianxing; Liu, Xin

    2011-12-01

    Forests are a major terrestrial ecosystem providing multiple ecosystem services. However, the importance of forests is frequently underestimated from an economic perspective because of the externalities and public good properties of these services. Forest eco-compensation is a transfer mechanism that serves to internalize the externalities of forest ecosystem services by compensating individuals or companies for the losses or costs resulting from the provision of these services. China's current forest eco-compensation system is centered mainly on noncommercial forest. The primary measures associated with ecosystem services are (1) a charge on destructive activities, such as indiscriminate logging, and (2) compensation for individual or local activities and investments in forest conservation. The Compensation Fund System for Forest Ecological Benefits was first listed in the Forest Law of the People's Republic of China in 1998. In 2004, the Central Government Financial Compensation Fund, an important source for the Compensation Fund for Forest Ecological Benefits, was formally established. To improve the forest eco-compensation system, it is crucial to design and establish compensation criteria for noncommercial forests. These criteria should take both theoretical and practical concerns into account, and they should be based on the quantitative valuation of ecosystem services. Although some initial headway has been made on this task, the implementation of an effective forest eco-compensation system in China still has deficiencies and still faces problems. Implementing classification-based and dynamic management for key noncommercial forests and establishing an eco-compensation mechanism with multiple funding sources in the market economy are the key measures needed to conquer these problems and improve the forest eco-compensation system and China's forestry development in sequence.

  19. Sampling Errors in Monthly Rainfall Totals for TRMM and SSM/I, Based on Statistics of Retrieved Rain Rates and Simple Models

    Science.gov (United States)

    Bell, Thomas L.; Kundu, Prasun K.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    Estimates from TRMM satellite data of monthly total rainfall over an area are subject to substantial sampling errors due to the limited number of visits to the area by the satellite during the month. Quantitative comparisons of TRMM averages with data collected by other satellites and by ground-based systems require some estimate of the size of this sampling error. A method of estimating this sampling error based on the actual statistics of the TRMM observations and on some modeling work has been developed. "Sampling error" in TRMM monthly averages is defined here relative to the monthly total a hypothetical satellite permanently stationed above the area would have reported. "Sampling error" therefore includes contributions from the random and systematic errors introduced by the satellite remote sensing system. As part of our long-term goal of providing error estimates for each grid point accessible to the TRMM instruments, sampling error estimates for TRMM based on rain retrievals from TRMM microwave (TMI) data are compared for different times of the year and different oceanic areas (to minimize changes in the statistics due to algorithmic differences over land and ocean). Changes in sampling error estimates due to changes in rain statistics due 1) to evolution of the official algorithms used to process the data, and 2) differences from other remote sensing systems such as the Defense Meteorological Satellite Program (DMSP) Special Sensor Microwave/Imager (SSM/I), are analyzed.

  20. Static compensators (STATCOMs) in power systems

    CERN Document Server

    Shahnia, Farhad; Ghosh, Arindam

    2014-01-01

    A static compensator (STATCOM), also known as static synchronous compensator, is a member of the flexible alternating current transmission system (FACTS) devices. It is a power-electronics based regulating device which is composed of a voltage source converter (VSC) and is shunt-connected to alternating current electricity transmission and distribution networks. The voltage source is created from a DC capacitor and the STATCOM can exchange reactive power with the network. It can also supply some active power to the network, if a DC source of power is connected across the capacitor. A STATCOM