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A convex approach to optimum design of experiments with correlated observations

ELECTRONIC JOURNAL OF STATISTICS 2022年第2期16卷 5659-5691页

作者： Pazman, Andrej Hainy, Markus Mueller, Werner G. Comenius Univ Bratislava Slovakia Johannes Kepler Univ Linz Linz Austria

Optimal design of experiments for correlated processes is an increasingly relevant and active research topic. Present methods have restricted possibilities to judge their quality. To fill this gap, we complement the virtual noise approach by a convex formulation leading to an equivalence theorem comparable to the uncorrelated case and to an algorithm giving an upper performance bound against which alternative design methods can be judged. Moreover, a method for generating exact designs follows naturally. We exclusively consider estimation problems on a finite design space with a fixed number of elements. A comparison on some classical examples from the literature as well as a real application is provided.

关键词： Correlated response design algorithm equivalence theorem Gaussian process

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design METHOD OF SYMMETRICAL VECTOR QUANTIZER

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ELECTRONICS LETTERS 1986年第16期22卷 848-849页

作者： MURAKAMI, T ASAI, K ITOH, A Information Systems & Electronics Development Laboratory Mitsubishi Electric Corporation Kamakura Japan

A new design algorithm is presented for a symmetric universal vector quantiser based on the successive partitioning of normalised signal space. The universal vector quantiser of video signals is also shown as an example.

关键词： image processing vectors video signals Mathematical analysis successive partitioning of normalised signal space design algorithm Optical information, image and video signal processing analogue-digital conversion symmetric vector quantiser picture processing

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Optimizing the universal visible antireflection coating design for substrates by exchanging search algorithms

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JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS 2005年第4A期44卷 1748-1751页

作者： Liou, YY Liu, YT Chienkuo Technol Univ Dept Elect Engn Changhua 500 Taiwan Nan Jeon Inst Technol Gen Educ Ctr Tainan 737 Taiwan

A design algorithm, based on the exchanging search technique, was used for optimizing the visible antireflection coating design of substrates with refractive indices ranging from 1.45 to 1.784. In this method, a tuning operation for the layer thicknesses of a two-material multilayer assembly was first carried out, followed by an exchanging operation for further refining the visible antireflection performance and simplifying the design structure. The average visible reflectivities of two-material thirty-layer exchanging search universal antireflection coating designs for a set of eight different substrates with indices 1.45, 1.50, 1.55, 1.60, 1.65, 1.70, 1.75 and 1.784 were reduced to approximately 0.172-0.174% with 12-14 layer structures.

关键词： antireflection coating multilayer design exchanging search visible spectral region design algorithm

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Wavelength-multiplexing diffractive phase elements: design, fabrication, and performance evaluation

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JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION 2001年第5期18卷 1082-1092页

作者： Ogura, Y Shirai, N Tanida, J Ichioka, Y Osaka Univ Grad Sch Engn Dept Mat & Life Sci Suita Osaka 5650871 Japan Nara Natl Coll Technol Yamato Koriyama Nara 6391080 Japan

We report on the wavelength-multiplexing diffractive phase element (WMDPE) capable of generating independent spot patterns for different wavelengths. The iterative method proposed by Bengtsson [Appl. Opt. 37, 1998] for designing a kinoform that produces different patterns for two wavelengths is extended to the WMDPE for multiple wavelengths (more than two wavelengths). Effectiveness of the design algorithm is verified by design and computer simulations on the WMDPE's for four and nine wavelengths, The WMDPE for three wavelengths (441.6, 543.5. and 633 nm) is designed with five phase levels and is fabricated by electron-beam lithography. We observed that the individual spot patterns are reconstructed for the design wavelengths correctly. Performance of the WMDPE is evaluated by computer simulations on the uniformity error. the light efficiency, and the contrast. On the basis of the results, the characteristics of the WMDPE's are discussed in terms of various conditions of fabrication and usage. (C) 2001 Optical Society of America.

关键词： Electron beam lithography Performance Evaluation design algorithm fabrication wavelengths Phase

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design and analysis of a cooling system for a supersonic exhaust diffuser

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PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART G-JOURNAL OF AEROSPACE ENGINEERING 2019年第14期233卷 5253-5263页

作者： Farahani, M. Fouladi, N. Mirbabaei, A. R. Sharif Univ Technol Dept Aerosp Engn Azadi StPOB 11365-11155 Tehran Iran Iranian Space Res Ctr Space Transportat Res Inst Tehran Iran

High-altitude test facilities are usually used to evaluate the performance of space mission engines. The supersonic exhaust diffuser, a main part of high-altitude test facility, provides the required test cell vacuum conditions by self-pumping the nozzle exhaust gases to the atmosphere. However, the plume temperature is often much higher than the temperature the diffuser structure is able to withstand, usually above 2500 K. In this study, an efficient cooling system is designed and analyzed to resolve the thermal problem. A water spray cooling technique is preferred among various existing techniques. Here, a new algorithm is developed for a spray cooling system for a supersonic exhaust diffuser. This algorithm uses a series of experimental and geometrical relationships to resize the governing parameters and remove the required heat flux from the diffuser surface. The efficiency of the newly designed cooling system is evaluated via numerical simulations. The utilized numerical technique is based on the discrete-phase method. Various computational studies are accomplished to enhance the accuracy of numerical prediction and validation. The present numerical study is validated using experimental results. The results show that the realizable k-e method is superior compared to other Reynolds-averaged Navier-Stokes models.

关键词： Supersonic exhaust diffuser water spray cooling design algorithm numerical simulation high-altitude test facility

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design of Overlapped Subarrays Based on Aperture Reactive Loading

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IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 2020年第7期68卷 5322-5333页

作者： Maximidis, Ronis T. Caratelli, Diego Toso, Giovanni Smolders, A. Bart Eindhoven Univ Technol Elect Engn Dept NL-5600 Eindhoven Netherlands Antenna Co Dept Res & Dev NL-5656 Eindhoven Netherlands Eindhoven Univ Technol Dept Elect Engn Electromagnet Grp NL-5600 Eindhoven Netherlands European Space Agcy ESA ESTEC Antenna & Submillimeter Wave Sect Electromagnet Div NL-2200 Noordwijk Netherlands

A novel technique is presented for the design and optimization of waveguide antenna arrays based on overlapping subarrays for limited field-of-view (FoV) applications. Each subarray consists of one directly fed antenna element and several passive reactive-loaded elements. The proposed overlapping scheme exploits a free-space reactive coupling instead of more conventional schemes based on complex beamforming networks. This results in a drastic reduction in the number of waveguide components required in the feeding network. The optimization of the considered class of array structures using a full-wave electromagnetic (EM) solver is extremely time-consuming even in the presence of subarrays with a reduced number of passive elements. To overcome this limitation, an effective semi-analytical design algorithm has been specifically developed. Using this algorithm, a novel subarray structure with a predefined pulse-shaped radiation pattern was synthesized. The designed subarray is inherently matched and features reduced spurious EM coupling level with adjacent subarray elements. In particular, the analysis of an array consisting of 38 such subarray elements has been carried out with the main goal of illustrating the effect of the subarray pattern on the total array characteristics. To validate the subarray overlapping scheme, an array composed of three contiguous subarrays has been realized and measured experimentally. In this way, a scan range in the FoV [-4 degrees;4 degrees] with 15 dB grating lobe suppression has been demonstrated.

关键词： Antenna arrays Electromagnetic waveguides Loaded antennas Apertures Loading Antenna radiation patterns Gratings Antenna arrays design algorithm limited field of view (FoV) reactive loading satellite communications subarrays waveguides

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Low torque ripple tooth coil windings multi-3-phase machines: design considerations and validation

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IET ELECTRIC POWER APPLICATIONS 2020年第2期14卷 262-273页

作者： Diana, Michela Ruffo, Riccardo Guglielmi, Paolo Politecn Torino Energy Dept Corso Duca Abruzzi 24 Turin Italy

In multi-n-phase machines, the n-phases are grouped in separated stars. A particular subcategory of multi-n-phase machines is the multi-3-phase machines. This study presents the design considerations and their validation for tooth coil wound multi-3-phase machines. A generic algorithm to design multi-3-phase machines is proposed. Although this study mainly focuses on multi-3-phase machines the approach is generalised and is applicable to any multi-n-phase machine. The resulting machines exhibit a low torque ripple value, and a mathematical formulation is proposed in order to justify this behaviour. All the multi-3-phase machines designed according to the proposed algorithm can be studied, and directly compared, thanks to the generalised harmonic formulation of the stator MMF and the torque performances here proposed. This study is enriched with some design hints useful to realise a machine with low mutual coupling between phases, and some considerations that can help the machine designer in the choice of the number of poles. The design algorithm is applied for the design of a triple-3-phase PM-inset machine solution, with nine slots ten poles. The performances, evaluated by finite element analysis and experimental analysis, demonstrate the effectiveness of the design algorithm proposed in a very simple structure machine.

关键词： finite element analysis stators rotors machine theory machine windings permanent magnet machines torque low torque ripple tooth coil windings multi3-phase machines design considerations phase machine wound multi3-phase machines design multi3-phase machines resulting machines machine designer design algorithm triple-3-phase PM-inset machine solution

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design OF IIR DIGITAL-FILTERS WITH ARBITRARY LOG MAGNITUDE FUNCTION BY WLS TECHNIQUES

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IEEE TRANSACTIONS ON ACOUSTICS SPEECH AND SIGNAL PROCESSING 1990年第2期38卷 247-252页

作者： KOBAYASHI, T IMAI, S Research Laboratory of Precision Machinery and Electronics Tokyo Institute of Technology Yokohama Japan

The authors propose a technique for designing IIR (infinite impulse response) digital filters to have an arbitrary log magnitude frequency response. The technique is based on an iterative weighted least-squares (WLS) approach in the frequency domain. A weight updating procedure is introduced to obtain a nearly optimal approximation to the given log magnitude function in the least-squares sense. The weighting function is updated using the results of the previous iteration in such a way that the weighted error approximates the log magnitude error. Filter coefficients at each iteration are efficiently computed using a fast recursive algorithm for a set of linear equations derived from the WLS problem. Several design examples demonstrate the rapid convergence of the design algorithm. The algorithm is extended to equiripple approximation by means of a minor modification of the weight updating procedure.

关键词： WEIGHTING FUNCTIONS IIR digital filter Recursive algorithms Linear equation design algorithm WLS gene optimal approximation weighted error Arbitrary iterative methods

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design of universal broadband visible antireflection coating for commonly used glass substrates

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JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS 2007年第8A期46卷 5143-5147页

作者： Liou, Yeuh-Yeong Liu, Chi-Chang Ku, Chin-Chiuan Liu, Wen-Chung Jaing, Cheng-Chung Chien Kuo Technol Univ Dept Elect Engn Changhua 500 Taiwan Chien Kuo Technol Univ Mech Engn & Grad Inst Mfg Technol Changhua 500 Taiwan Natl Formosa Univ Dept Aeronaut Engn Yunlin 632 Taiwan Mingshin Univ Sci & Technol Dept Optoelect Syst Engn Hsinchu 304 Taiwan

We designed a universal broadband visible antireflection coating for glass substrates with refractive indices ranging from 1.45 to 1.90 by a jumping search technique. The jumping search algorithm, based on the searches of layer-thickness jump tuning and layer jump elimination, was used to refine the mean visible antireflection performance and simplify the design structure of a multilayer system. It was shown that the universal visible antireflection coating designs for a set of 10 different substrates with the refractive indices of 1.45, 1.50, 1.55, 1.60, 1.65, 1.70, 1.75, 1.80, 1.85, and 1.90, obtained by different types of Jumping search of a two-material 50-layer system, were reduced to 18-22-layered structures and their total average universal visible reflectivities reduced to approximately 0.307-0.309% were acceptable.

关键词： universal visible antireflection coating jumping search design algorithm broadband multilayer system

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Luenberger observer-based H infinity-compensator design for nonstandard problems

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IEEE TRANSACTIONS ON AUTOMATIC CONTROL 1996年第9期41卷 1364-1367页

作者： Yu, XG Hsu, CS The School of Electrical Engineering and Computer Science Washington State University Pullman WA USA

This paper presents Luenberger observer-based H-x-compensator design methods for different nonstandard cases. These design methods are developed based on the bounded real lemma, and the resultant design algorithms are... 详细信息

关键词： Lemma design approach inequalities Observers design algorithm Resultant algorithms Real number Bounded

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