Simple Design Algorithm Research Articles

A simple algorithm for optimal design in distributed fibre-optic sensing

SUMMARY We present a basic algorithm for optimal experimental design in distributed fibre-optic sensing. It is based on the fast random generation of fibre-optic cable layouts that can be tested for their cost-benefit ratio. The algorithm accounts for the maximum available cable length, lets the cable pass through pre-defined points of interest, avoids obstacles that the cable must not traverse, permits the adaptation of geometric complexity of different cable segments and allows for the incorporation of topography. Furthermore, the algorithm can be combined with arbitrary measures of the cost-benefit ratio, and its simplicity enables easy adaptations to the needs of specific applications. In addition to a description of the basic concept, we provide examples that illustrate the circumnavigation of obstacles, the steering of geometric complexity and the cable layout optimization in the presence of topographic variations.

Periodic tracking for piezo‐actuated displacement stage based on disturbance rejection proportional integral derivative and repetitive control

AbstractPiezo‐actuated displacement stage is often used to perform periodic scanning tasks, but the conventional control schemes may not satisfactorily track periodic reference signals. Our solution is a disturbance rejection proportional‐integral‐derivative (DR‐PID)‐based repetitive control (RC) scheme in which the hysteresis nonlinearity with the same period of reference input can be well suppressed by RC law. Stability criterions for the closed‐loop system are developed based on small‐gain theorem. A simple and effective design algorithm is obtained based on the stability conditions, such that DR‐PID and RC can be designed separately. Finally, the validation and superiority of the proposed method are demonstrated by simulation studies.

Topological Derivative-Based Topology Optimization of Plate Structures Under Bending Effects

In this work, the topological derivatives of L2 and energy norms associated with the solution to Kirchhoff and Reissner-Mindlin plate bending models are introduced. Based on existing theoretical results, closed forms of the sensitivities are presented. A zero-order term is introduced in the equilibrium equations, which allows for adapting the obtained sensitivities to the context of topology optimization of plates under elastic support and free vibration condition as well. The resulting analytical formulae are used together with a level-set domain representation method to devise a simple topology design algorithm. Several finite element-based representative numerical experiments are presented showing its applications to the compliance minimization and eigenvalue maximization of Kirchhoff as well as Reissner-Mindlin plate structures under bending effects.

Topological asymptotic analysis of a diffusive–convective–reactive problem

PurposeThe purpose of this study is sensitivity analysis of the L2-norm and H1-seminorm of the solution of a diffusive–convective–reactive problem to topological changes of the underlying material.Design/methodology/approachThe topological derivative method is used to devise a simple and efficient topology design algorithm based on a level-set domain representation method.FindingsRemarkably simple analytical expressions for the sensitivities are derived, which are useful for practical applications including heat exchange topology design and membrane eigenvalue maximization.Originality/valueThe topological asymptotic expansion associated with a diffusive–convective–reactive equation is rigorously derived, which is not available in the literature yet.

Interpolatory Curve Modeling with Feature Points Control

In curve modeling, interpolation allows users to directly control the location of curve features. While previous literatures have focused on generating interpolatory curves with properties of smoothness and locality, they usually have difficulty in controlling over geometric feature points (e.g., cusps, loops, and inflection points) that mark salient intrinsic features of curve shapes. In this paper, we propose an intuitive and efficient method for constructing planar cubic curves that are curvature continuous almost-everywhere and interpolate a sequence of input data points. Our method provides a good control over the location and type of the geometric feature points. In particular, cusps and loops only occur at specified input data points, while inflection points only occur at specified input data points and joints. We refer to such feature points controlled interpolatory curves as FPC-Curves for short. To construct FPC-Curves, we focus on piecewise cubic curves, where the occurrence of loops, cusps and inflection points is mutually exclusive. We also provide a simple yet efficient algorithm for real-time interactive design of cubic FPC-Curves. Various experimental results show the efficacy and flexibility of our new approach for curve modeling.

A simple multiobjective evolutionary algorithm for design of digital maps

A simple multiobjective evolutionary algorithm for design of digital maps

Model-Based Analysis of Stretch Film Consumption for Wrapping Cylindrical Baled Silage Using Combined 3D Method

Abstract. A combined method for wrapping round (i.e., cylindrical) bales of agricultural materials based on biaxial rotation of the film applicators is considered in this study. A complete mathematical model is derived describing the consumption of the film used to wrap the bales that can be applied for film consumption estimation and design purposes. The bale and film dimensions, mechanical properties of the stretch film described by Poisson ratio and unit deformation, dimensionless relative overlap ratios determining the width of the contact area between adjacent film strips, and the assumed number of nominal film layers are taken into account. There is a need for good understanding of the influence of the wrapping process parameters on film consumption so that this method can be applied with lower cost and less damage to the environment. Based on the derived model, insight is obtained into the influence of the film width and wrapping parameters on film consumption when the combined method is used. Robustness on disturbances of the wrapping process, which lead to parameter uncertainty, is examined, and a simple algorithm for robust design of the overlaps of the bottom film layers is developed. The alternative method for wrapping round bales is the conventional method used by bale wrappers with a rotating table or with rotating arms. In this study, film consumption is compared between the combined and conventional wrapping methods. The combined wrapping method may offer substantial advantages in reduced film use compared with the conventional method. The potential reduction in film usage depends on the bale, film, and wrapping parameters. Without the proper choice of parameters, film consumption may be unjustifiably high. The model-based necessary and sufficient conditions for film usage reduction are obtained under typical assumptions concerning the bale and film parameters as well as the wrapping process parameters. No specific assumptions are made concerning the assumed number of film layers. The results concerning film usage reduction are written in the form of mathematical inequalities in terms of film, bale, and wrapping parameters. The stated conditions are useful for film consumption analysis and provide easy-to-use tools for analytical and numerical design of bale wrapping processes. A fast scheme is proposed for determining if the considered film parameters, together with the assumed number of film layers, could result in reduced film usage. For the algorithms, the executable and readable source codes are written in Matlab. Model-based simulations provide valuable insight into the underlying processes of film consumption and are shown to be useful for wrapping process design. To ensure a fair comparison, four to ten film layers are considered. Keywords: Baled silage, Film usage reduction, Mathematical models, Robustness, Stretch-wrap film consumption.

Compact H-plane dual-band bandstop waveguide filter

This paper proposes a third-order miniaturized H-plane dual-band bandstop waveguide filter. Split ring resonators (SRRs), in the form of printed-circuit inserts, are used for the filter design. A simple and straightforward novel design algorithm for the waveguide SRR is introduced, which provides essential foundation for the development of the H-plane filter with multiple individually tunable stopbands. The third-order H-plane dual-band bandstop filter is implemented using SRRs for each stopband separated by quarter-wavelength waveguide sections to realize the immittance inverters for the corresponding center frequencies. Miniaturization of the filter is accomplished by the use of a properly designed insert within the waveguide section acting as the inverter. To demonstrate the usefulness of the proposed novel design algorithm and miniaturization concept, a compact H-plane dual-band bandstop waveguide filter is designed featuring independent control of the specified stopbands. The stopbands are located at center frequencies $$f_{01}=8.90\hbox { GHz}$$ and $$f_{02}=10.90\hbox { GHz}$$ and exhibit equal bandwidths of 340 MHz. The undesirable coupling between the SRRs for different stopbands on the insert is eliminated, along with their respective couplings to the additional insert for the inverter miniaturization. Thus, each of the stopbands is flexibly tuned by the adjustment of dimensions of the particular SRR. The proposed design using a shorter inverter preserves the characteristics of the conventional filter, while the improvement of the overall device in terms of compactness is 32%. The designed compact H-plane dual-band bandstop waveguide filter is experimentally validated, and the three-dimensional electromagnetic simulation and measurement results are in good agreement.

Feedback control of heart rate during outdoor running: A smartphone implementation

The aim was to develop and to investigate the technical feasibility of a novel smartphone-based mobile system for feedback control of heart rate during outdoor running. Accurate control is important because heart rate can be used for prescription of exercise intensity for development and maintenance of cardiorespiratory fitness. An Android smartphone was employed together with wearable, wireless sensors for heart rate and running speed. A simple feedback design algorithm appropriate for embedded mobile applications was developed. Controller synthesis uses a low-order, physiologically-validated plant model and requires a single bandwidth-related tuning parameter. Twenty real time controller tests demonstrated highly accurate tracking of target heart rate with a mean root-mean-square tracking error (RMSE) of less than 2 beats per minute (bpm); a sufficient level of robustness was demonstrated within the range of conditions tested. Adjustment of the tuning parameter towards lower closed-loop bandwidth gave markedly lower control signal power (0.0008 vs. 0.0030 m2/s2, p < 0.0001, low vs. high bandwidth), but at the cost of a significantly lower heart rate tracking accuracy (RMSE 1.99 vs. 1.67 bpm, p < 0.01). The precision achieved suggests that the system might be applicable for accurate achievement of prescribed exercise intensity for development and maintenance of cardiorespiratory fitness. High-accuracy feedback control of heart rate during outdoor running using smartphone technology is deemed feasible.

Topology design of plates considering different volume control methods

Purpose – The purpose of this paper is to compare between two methods of volume control in the context of topological derivative-based structural optimization of Kirchhoff plates. Design/methodology/approach – The compliance topology optimization of Kirchhoff plates subjected to volume constraint is considered. In order to impose the volume constraint, two methods are presented. The first one is done by means of a linear penalization method. In this case, the penalty parameter is the coefficient of a linear term used to control the amount of material to be removed. The second approach is based on the Augmented Lagrangian method which has both, linear and quadratic terms. The coefficient of the quadratic part controls the Lagrange multiplier update of the linear part. The associated topological sensitivity is used to devise a structural design algorithm based on the topological derivative and a level-set domain representation method. Finally, some numerical experiments are presented allowing for a comparative analysis between the two methods of volume control from a qualitative point of view. Findings – The linear penalization method does not provide direct control over the required volume fraction. In contrast, through the Augmented Lagrangian method it is possible to specify the final amount of material in the optimized structure. Originality/value – A strictly simple topology design algorithm is devised and used in the context of compliance structural optimization of Kirchhoff plates under volume constraint. The proposed computational framework is quite general and can be applied in different engineering problems.

Linear periodic controller design for decentralized control systems

In the decentralized control of linear time-invariant (LTI) systems, a decentralized fixed mode (DFM) is a system mode which is immoveable using an LTI controller, while a quotient DFM (QDFM) is one which is immoveable using any form of nonlinear time-varying compensation. If a system has no unstable DFMs, there are well-known procedures for designing an LTI stabilizing controller; for systems which have unstable DFMs but no unstable QDFMs, we provide a simple design algorithm which yields a linear periodic sampled-data stabilizing controller.

간섭 채널을 위한 통합 궤환 정보 설계

In this paper, we study joint feedback design for interference channel (IC). We develop a simple iterative algorithm for the joint feedback design to maximize the expected rate when the transmitters use partial channel-state information (CSI) obtained by the feedback link. Also, from the simulation result, we show that the performance gain is obtained compared to the conventional scheme.

Reconstruction of the Saccharopolyspora erythraea genome-scale model and its use for enhancing erythromycin production

Genome-scale metabolic reconstructions are routinely used for the analysis and design of metabolic engineering strategies for production of primary metabolites. The use of such reconstructions for metabolic engineering of antibiotic production is not common due to the lack of simple design algorithms in the absence of a cellular growth objective function. Here, we present the metabolic network reconstruction for the erythromycin producer Saccharopolyspora erythraea NRRL23338. The model was manually curated for primary and secondary metabolism pathways and consists of 1,482 reactions (2,075 genes) and 1,646 metabolites. As part of the model validation, we explored the potential benefits of supplying amino acids and identified five amino acids "compatible" with erythromycin production, whereby if glucose is supplemented with this amino acid on a carbon mole basis, the in silico model predicts that high erythromycin yield is possible without lowering biomass yield. Increased erythromycin titre was confirmed for four of the five amino acids, namely valine, isoleucine, threonine and proline. In bioreactor experiments, supplementation with 2.5 % carbon mole of valine increased the growth rate by 20 % and simultaneously the erythromycin yield on biomass by 50 %. The model presented here can be used as a framework for the future integration of high-throughput biological data sets in S. erythraea and ultimately to realise strain designs capable of increasing erythromycin production closer to the theoretical yield.

Stability Analysis and Design of Time‐Varying Nonlinear Systems Based on Impulsive Fuzzy Model

This paper develops a general analysis and design theory for nonlinear time‐varying systems represented by impulsive T‐S fuzzy control model, which extends conventional T‐S fuzzy model. In the proposed, model impulse is viewed as control input of T‐S model, and impulsive distance is the major controller to be designed. Several criteria on general stability, asymptotic stability, and exponential stability are established, and a simple design algorithm is provided with stability of nonlinear time‐invariant systems. Finally, the numerical simulation for the predator‐prey system with functional response and impulsive effects verify the effectiveness of the proposed methods.

Non-Uniform 2-Slot Constellations for Bidirectional Relaying in Fading Channels

In this paper we introduce the constellation alphabets suitable for bidirectional relaying in parametric wireless channels. Based on the analysis of hierarchical minimum distance, we present a simple design algorithm for the non-uniform 2-slot constellation alphabets. These novel constellation alphabets outperform traditional linear modulation schemes in Hierarchical-Decode-and-Forward and Denoise-and-Forward relaying strategies in fading channels without sacrificing the overall system throughput.

Power minimization for CDMA under colored noise

Rate-constrained power minimization (PMIN) over a code division multiple-access (CDMA) channel with correlated noise is studied. PMIN is shown to be an instance of a separable convex optimization problem subject to linear ascending constraints. PMIN is further reduced to a dual problem of sumrate maximization (RMAX). The results highlight the underlying unity between PMIN, RMAX, and a problem closely related to PMIN but with linear receiver constraints. Subsequently, conceptually simple sequence design algorithms are proposed to explicitly identify an assignment of sequences and powers that solve PMIN. The algorithms yield an upper bound of 2N - 1 on the number of distinct sequences where N is the processing gain. The sequences generated using the proposed algorithms are in general real-valued. If a rate-splitting and multi-dimensional CDMA approach is allowed, the upper bound reduces to N distinct sequences, in which case the sequences can form an orthogonal set and be binary plusmn1-valued.

Transactions papers evaluation and design of irregular LDPC codes using ACE spectrum

The construction of finite-length irregular LDPC codes with low error floors is currently an attractive research problem. In particular, for the binary erasure channel (BEC), the problem is to find the elements of selected irregular LDPC code ensembles with the size of their minimum stopping set being maximized. Due to the lack of analytical solutions to this problem, a simple but powerful heuristic design algorithm, the approximate cycle extrinsic message degree (ACE) constrained design algorithm, has recently been proposed. Building upon the ACE metric associated with a cycle in a code graph, we introduce the ACE spectrum of LDPC codes as a useful tool for evaluation of codes from selected irregular LDPC code ensembles. Using the ACE spectrum, we generalize the ACE constrained design algorithm, making it more flexible and efficient. We justify the ACE spectrum approach through examples and simulation results.

SU-FF-T-668: A Simple Algorithm for Range Modulation Wheel Design in Proton Therapy

Purpose: To develop a simple algorithm in designing the range modulation wheel to generate a very smooth Spread‐Out Bragg peak (SOBP) for proton therapy.Method and Materials: A simple algorithm has been developed to generate the weight factors in corresponding pristine Bragg peaks which composed a smooth SOBP in proton therapy. We used a modified analytical Bragg peak function based on Monte Carol simulation tool‐kits of Geant4 as pristine Bragg peaks input in our algorithm. A simple METLAB© Quad Program was introduced to optimize the cost function in our algorithm. Results: We found out that the existed analytical function of Bragg peak can't directly use as pristine Bragg peak dose‐depth profile input file in optimization of the weight factors since this model didn't take into account of the scattering factors introducing from the range shifts in modifying the proton beam energies. We have done Geant4 simulations for proton energy of 63.4 MeV with a 1.08 cm SOBP for variation of pristine Bragg peaks which composed this SOBP and modified the existed analytical Bragg peak functions for their peak heights, ranges of R0, and Gaussian energies σE. We found out that 19 pristine Bragg peaks are enough to achieve a flatness of 1.5% of SOBP which is the best flatness in the publications. Conclusion: This work develops a simple algorithm to generate the weight factors which is used to design a range modulation wheel to generate a smooth SOBP in protonradiation therapy. We have found out that a medium number of pristine Bragg peaks are enough to generate a SOBP with flatness less than 2%. It is potential to generate data base to store in the treatment plan to produce a clinic acceptable SOBP by using our simple algorithm.

Output feedback variable structure control design with an [formula omitted] performance bound constraint

In this paper, we give an LMI-based method for designing an output feedback variable structure control (VSC) system with an H 2 constraint. The uncertain system model under consideration may have nonmatching disturbance input signals. Nonmatching disturbance input signal reduction is performed via H 2 norm minimization. In terms of a constrained Riccati inequality we give a sufficient condition for the existence of a linear sliding surface and a compensator guaranteeing an H 2 constraint, and we show that the control parameters can be characterized by using the solution to the given inequality condition. We also give a simple LMI-based design algorithm of an output feedback VSC law guaranteeing an H 2 constraint. Finally, by using a design example we show that our method can supplement the existing results.

전차수 슬라이딩 모드 관측기를 대체하는 축소차수 관측기의 LMI 기반 설계

This paper presents an LMI-based method to design reduced order observers by which we can substitute full order sliding mode observers for a class of uncertain time-delay systems. We show that a reduced order observer can be constructed as long as the uncertain system satisfies the previous LMI existence conditions of a full order sliding mode observer. And we give explicit formulas of the reduced order observer gain matrices. Finally, we give a simple LMI-based design algorithm, together with a numerical design example.