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Design Scheme (design + scheme)
Selected AbstractsProcDef: Local-to-global Deformation for Skeleton-free Character AnimationCOMPUTER GRAPHICS FORUM, Issue 7 2009Takashi Ijiri Abstract Animations of characters with flexible bodies such as jellyfish, snails, and, hearts are difficult to design using traditional skeleton-based approaches. A standard approach is keyframing, but adjusting the shape of the flexible body for each key frame is tedious. In addition, the character cannot dynamically adjust its motion to respond to the environment or user input. This paper introduces a new procedural deformation framework (ProcDef) for designing and driving animations of such flexible objects. Our approach is to synthesize global motions procedurally by integrating local deformations. ProcDef provides an efficient design scheme for local deformation patterns; the user can control the orientation and magnitude of local deformations as well as the propagation of deformation signals by specifying line charts and volumetric fields. We also present a fast and robust deformation algorithm based on shape-matching dynamics and show some example animations to illustrate the feasibility of our framework. [source] Studies on seismic reduction of story-incresed buildings with friction layer and energy-dissipated devicesEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 14 2003Hong-Nan Li Abstract A new type of energy-dissipated structural system for existing buildings with story-increased frames is presented and investigated in this paper. In this system the sliding-friction layer between the lowest increased floor of the outer frame structure and the roof of the original building is applied, and energy-dissipated dampers are used for the connections between the columns of the outer frame and each floor of the original building. A shaking table test is performed on the model of the system and the simplified structural model of this system is given. The theory of the non-classical damping approach is introduced to the calculation analyses and compared with test results. The results show that friction and energy-dissipated devices are very effective in reducing the seismic response and dissipating the input energy of the model structure. Finally, the design scheme and dynamic time-history analyses of an existing engineering project are investigated to illustrate the application and advantages of the given method. Copyright © 2003 John Wiley & Sons, Ltd. [source] Anti-windup synthesis for nonlinear dynamic inversion control schemesINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 13 2010G. Herrmann Abstract A general anti-windup (AW) compensation scheme is provided for a class of input constrained feedback-linearizable nonlinear systems. The controller considered is an inner-loop nonlinear dynamic inversion controller, augmented with an outer-loop linear controller, of arbitrary structure. For open-loop globally exponentially stable plants, it is shown that (i) there always exists a globally stabilizing AW compensator corresponding to a nonlinear generalization of the Internal-Model-Control (IMC) AW solution; (ii) important operator theoretic parallels exist between the AW design scheme for linear control and the suggested AW design scheme for nonlinear affine plants and (iii) a more attractive AW compensator may be obtained by using a nonlinear state-feedback term, which plays a role similar to the linear state-feedback term in linear coprime factor-based AW compensation. The results are demonstrated on a dual-tank simulation example. Copyright © 2009 John Wiley & Sons, Ltd. [source] Reduced-order impulsive control for a class of nonlinear systemsINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 8 2010Yan-Wu Wang Abstract Impulsive control of nonlinear systems is an attractive topic and a number of interesting results have been obtained in the recent years. However, most of the available results need to employ full information of the system states to achieve the desired objectives. In this paper, a reduced-order impulsive control strategy that needs only part of state components is studied for a general class of nonlinear system, which is feasible for the case when some of the system states are not available or controllable. Typical chaotic systems, such as Lorenz system, Chua's oscillator, and Chen's system, are taken as examples. A systematic design scheme is proposed to select the impulsive intervals. After some theoretical analysis, simulation results illustrate the effectiveness of the proposed control scheme. Copyright © 2009 John Wiley & Sons, Ltd. [source] Design of fault-tolerant control for MTTFINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 16 2008Hongbin Li Abstract Mean time to failure (MTTF) is an important reliability index of fault-tolerant control systems, which is chosen as a design objective in this paper. However, it is usually evaluated from stochastic reliability models, and no analytical expression is available to relate MTTF to controller parameters. To overcome this difficulty, a two-stage design scheme is proposed in this paper: A gradient-based search is firstly carried out on probabilistic H, performance characteristics for MTTF requirement; a sequential randomized algorithm with a weighted violation function is then developed for a controller design to satisfy the required H, performance, and its convergence is guaranteed with probability 1. Two iterative algorithms are carried out alternately to implement this scheme, and a controller can be designed for MTTF requirement. Copyright © 2008 John Wiley & Sons, Ltd. [source] Stable robust feedback control system design for unstable plants with input constraints using robust right coprime factorizationINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 18 2007Mingcong Deng Abstract A stable robust control system design problem for unstable plants with input constraints is considered using robust right coprime factorization of nonlinear operator. For obtaining strong stability of the closed-loop system of unstable plants with input constraints, a design scheme of robust nonhyphen-linear control system is given based on robust right coprime factorization. Some conditions for the robustness and system output tracking of the unstable plant with input constraints are derived. Numerical examples are given to demonstrate the validity of the theoretical results. Copyright © 2007 John Wiley & Sons, Ltd. [source] Broadband built-in antenna with new enclosed 3D coupling feed structureMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2010Byoung-Nam Kim Abstract Wideband built-in antenna with an enclosed 3D coupling feed structure for wireless terminals is presented. With the proposed design scheme, a nine-band built-in antenna that covers GSM850/GSM900/GPS/DCS1800/PCS1900/WCDMA/WiBro2350/Bluetooth/WiMax 2500 is experimentally tested. This novel nine-band built-in handset antenna is developed within the limits of a 40 × 17.5 × 6 mm3 volume, achieving good agreement between measurement and simulation. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2306,2309, 2010; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/mop.25441 [source] High-performance UWB filter with a controllable notched bandMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 8 2010Chun-Ping Chen Abstract This article presents a design of a high-performance ultra-wideband (UWB) bandpass filter with a controllable notched band. Firstly, a UWB filter consisting of a stepped-impedance resonator (SIR) and two shunt short-circuited stubs is synthesized. Then, a narrow controllable notched band is introduced by a coupled external SIR. To be highlighted as an attractive advantage, as the characteristics of the UWB filter are not deteriorated by the placement of the external resonator, no further adjustments is needed for the synthesized UWB filter in this design. As an example, an (Federal Communications Commission) FCC UWB filter with a WLAN notch band is designed, simulated, and fabricated. A good agreement between the measured results and predicted ones validates the newly proposed design scheme and the filter prototype. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1842,1846, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25354 [source] A Design Of Multiloop Predictive Self-Tuning Pid ControllersASIAN JOURNAL OF CONTROL, Issue 4 2002Masaru Katayama ABSTRACT In this paper, a new design scheme of multiloop predictive self-tuning PID controllers is proposed for multivariable systems. The proposed scheme firstly uses a static pre-compensator as an approximately decoupling device, in order to roughly reduced the interaction terms of the controlled object. The static matrix pre-compensator is adjusted by an on-line estimator. Furthermore, by regarding the approximately decoupled system as a series of single-input single-output subsystems, a single-input single-output PID controller is designed for each subsystem. The PID parameters are calculated on-line based on the relationship between the PID control and the generalized predictive control laws. The proposed scheme is numerically evaluated on a simulation example. [source] Bayesian Optimal Designs for Phase I Clinical TrialsBIOMETRICS, Issue 3 2003Linda M. Haines Summary. A broad approach to the design of Phase I clinical trials for the efficient estimation of the maximum tolerated dose is presented. The method is rooted in formal optimal design theory and involves the construction of constrained Bayesian c - and D -optimal designs. The imposed constraint incorporates the optimal design points and their weights and ensures that the probability that an administered dose exceeds the maximum acceptable dose is low. Results relating to these constrained designs for log doses on the real line are described and the associated equivalence theorem is given. The ideas are extended to more practical situations, specifically to those involving discrete doses. In particular, a Bayesian sequential optimal design scheme comprising a pilot study on a small number of patients followed by the allocation of patients to doses one at a time is developed and its properties explored by simulation. [source] Critical review of oral drug treatments for diabetic neuropathic pain,clinical outcomes based on efficacy and safety data from placebo-controlled and direct comparative studiesDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 3 2005Hugo Adriaensen Abstract The present review aims to evaluate the efficacy and safety of a selection of oral treatments for the management of painful diabetic neuropathy. A literature review was conducted retrieving placebo-controlled and direct comparative studies with a selection of oral treatments for painful diabetic neuropathy. All studies were analyzed with regard to efficacy and tolerability. Efficacy was evaluated as the percentage improvement in pain intensity between baseline and endpoint. Tolerability was evaluated by means of study discontinuations due to adverse events and by incidence of drug-related adverse events. The analyzed trials enrolled different patient populations with mostly small numbers of patients. The great variability in dosages and dose titration schemes, cross-over designs with variable wash-out periods, and other design schemes made comparison between the different studies difficult. Gabapentin, lamotrigine, tramadol, oxycodone, mexiletine, and acetyl-L-carnitine were the only treatments studied in large (at least 100 patients), placebo-controlled parallel group trials. It is concluded that standardization in design and reporting for comparison of treatments is needed. Validated questionnaires for evaluation of the efficacy and safety should be further developed. Based on the reviewed randomised controlled trials, gabapentin shows good efficacy, a favourable side-effect profile with lack of drug interactions and therefore it may be a first choice treatment in painful diabetic neuropathy, especially in the elderly. However, head to head trials of current treatments are lacking and therefore randomized controlled trials are required to address this issue. Copyright © 2005 John Wiley & Sons, Ltd. [source] Convergence of control performance by unfalsification of models,levels of confidenceINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 5 2001S. M. Veres Abstract A general framework is introduced for iterative/adaptive controller design schemes by model unfalsification. An important feature of the schemes is their convergence near to the best possible controller given a set of model and controller structures. The problem of stability assured controller tuning is examined through unfalsified Riemannian bands of the Nyquist plot. Instability tolerant H, and l1 -norm-based controller tuning schemes are introduced. Computational problems are discussed and a simulation is used to illustrate the new scheme. Copyright © 2001 John Wiley & Sons, Ltd. [source] A survey in the park: Methodological and practical problems associated with geophysical investigation in a late Victorian municipal parkARCHAEOLOGICAL PROSPECTION, Issue 3 2010Andrew Parkyn Abstract The survey of Pudsey Park is a geophysical investigation of a late Victorian municipal park. The aim of the survey was to use geophysical techniques to identify the park's changing designs over a 120 year period. An initial design for the park was located during the desk-based assessment, however, it was unclear how much of the original plan had been implemented. It was suspected that Pudsey Park's design has been simplified over time. The project also aimed to identify a suitable sampling strategy for studying park and garden sites by using high-resolution surveys and multiple probe separations for varying depths of detection during earth resistance survey. It was hoped that multiple electrode separations combined with a high density survey could be used to differentiate the signal responses from the modern park designs and earlier design schemes. The choice of strategy is at a significantly higher resolution than guidelines for geophysical investigations for traditional archaeological features. The survey provided highly detailed but complicated data sets; areas of the park have had several redesigns, often where the modern scheme masks previous designs. A number of ,hard' and ,soft' landscaping features were identified including the foundations of the original bandstand (now replaced) and former flower beds. The 0.25,m probe separation surprisingly produced the most defined data with the greatest level of information due to the increased spatial resolution. The geophysical investigation is the first of its kind to investigate a Victorian municipal park in its entirety. The survey validates the importance of high-resolution survey in the study of parks and gardens and also provides a reference data set for future work where poorer documentation hinders interpretation. The geophysics data, together with the accompanying Geographical Information System database produce a unique and detailed picture of a Victorian park from its inception through 120 years of development. Copyright © 2010 John Wiley & Sons, Ltd. [source] | ||||||||||