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Fundamental techniques for order optimization

David Simmen, Eugene Shekita, Timothy Malkemus
1996 SIGMOD record  
The next section looks at the fundamental operations on interesting orders needed to accomplish these tasks. 4 Fundamental Operations for Order Optimization 4.1 Reduce Order The  ...  Among other things, the DB2 optimizer uses much more sophis- ticated techniques for order optimization.  ... 
doi:10.1145/235968.233320 fatcat:l2poklyn4nh43bstgsdc5rrxly

Fundamental techniques for order optimization [chapter]

David Simmen, Eugene Shekita, Timothy Malkemus
1996 Lecture Notes in Computer Science  
The next section looks at the fundamental operations on interesting orders needed to accomplish these tasks. 4 Fundamental Operations for Order Optimization 4.1 Reduce Order The  ...  Among other things, the DB2 optimizer uses much more sophis- ticated techniques for order optimization.  ... 
doi:10.1007/bfb0014183 fatcat:ccnk2twmibasllxm3b2zvpoigq

Fundamental techniques for order optimization

David Simmen, Eugene Shekita, Timothy Malkemus
1996 Proceedings of the 1996 ACM SIGMOD international conference on Management of data - SIGMOD '96  
The next section looks at the fundamental operations on interesting orders needed to accomplish these tasks. 4 Fundamental Operations for Order Optimization 4.1 Reduce Order The  ...  Among other things, the DB2 optimizer uses much more sophis- ticated techniques for order optimization.  ... 
doi:10.1145/233269.233320 dblp:conf/sigmod/SimmenSM96 fatcat:ijcns2c475gvdgahnahygw2yna

OPTIMIZATION TECHNIQUES FOR HARMONICS MINIMIZATION IN CASCADED HYBRID MULTILEVEL CONVERTERS: A REVIEW

Parul Gaur .
2015 International Journal of Research in Engineering and Technology  
This paper presents a review of optimization techniques used for multilevel inverters. The pros and cons of optimization techniques are discussed.  ...  Over the past decades, depending upon the topologies and control strategies, numerous optimization techniques have been proposed for desired output waveform.  ...  Genetic algorithm (GA) technique is used in [19] for eliminating some higher order harmonics while maintaining the required fundamental voltage.  ... 
doi:10.15623/ijret.2015.0403033 fatcat:mvyugvar75g3jfcg7zfepai6xq

An improved OMTHD technique for an $n$-level cascaded multilevel inverter with adjustable DC sources

Hamidreza TOODEJI
2017 Turkish Journal of Electrical Engineering and Computer Sciences  
Moreover, optimal DC voltages and switching angles can be estimated simpler than conventional OMTHD technique.  ...  In the former technique, the THD of waveform is reduced without elimination of any harmonic order and the latter, in contrast, eliminates selected harmonic orders.  ...  Figure 6 . 6 Switching angles vs. modulation index for (a) conventional, (b) improved OMTHD techniques 'simulation results'. harmonic orders from 11 to 49 at the base of the fundamental component for both  ... 
doi:10.3906/elk-1706-121 fatcat:ksodzjiwyngthlom43rslljamy

Harmonic Elimination of Seven Level Inverter with Switching Pattern Reconfiguration Technique Using Hybrid BBO/MAS Algorithm

R. Kavitha, Rani Thottungal, Brindha. R
2016 International Journal of Applied Power Engineering (IJAPE)  
The fundamental frequency Selective Harmonic Elimination-Pulse Width Modulation (SHE-PWM) technique is applied in order to reduce the switching losses.Reconfiguration technique is also proposed to achieve  ...  harmonic elimination for entire Modulation index(M).  ...  HYBRID BBO/MAS OPTIMIZATION TECHNIQUE 4.1.  ... 
doi:10.11591/ijape.v5.i2.pp79-86 fatcat:y6rubfq5hzdozi5ywkap4u2n7m

Harmonics Reduction in Cascade H-Bridge Multilevel Inverters Using GA and PSO
English

Aman Parkash, S.L Shimi, S Chatterji
2014 International Journal of Engineering Trends and Technoloy  
These non-linear complex equations is minimized by the using of particle swarm optimization (PSO) and genetic algorithm (GA) techniques, and also have been compared the simulating and analyzing results  ...  For generating the optimized staircase voltage waveform, the optimized switching angles are obtained using by the particle swarm optimization (PSO) and genetic algorithm (GA) techniques. II.  ...  important for optimizing the conducting angles.  ... 
doi:10.14445/22315381/ijett-v12p287 fatcat:7hgrddoyrvftvpkw2tbqlokfhq

On the Estimation of the Fundamental Matrix: A Convex Approach to Constrained Least-Squares [chapter]

G. Chesi, A. Garulli, A. Vicino, R. Cipolla
2000 Lecture Notes in Computer Science  
First, we show how this nonconvex optimization problem can be solved avoiding local minima using recently developed convexi cation techniques.  ...  Here we present a method for obtaining a more accurate estimate of the fundamental matrix with respect to the linear criterion.  ...  Acknowledgments We would like to thank Alberto Tesi for his useful hints on the optimization section and Richard Hartley for providing the image sequences and data he used  ... 
doi:10.1007/3-540-45054-8_16 fatcat:qm6ya56kvnb33mjqv5pxa6esgu

GA Based Selective Harmonic Elimination for Five-Level Inverter Using Cascaded H-bridge Modules

Enes Bektas, Hulusi Karaca
2016 International Journal of Intelligent Systems and Applications in Engineering  
Simulation results have clearly demonstrated that GA based SHE techniques can eliminate the demanded harmonic orders.  ...  In this paper, SHE equations have been solved by using of Genetic Algorithm (GA) Toobox&Matlab and it has been aimed to eliminate desired harmonic orders at fundamental output voltage.  ...  Figure 4 . 4 The calculated switching angles by Optimization Toolbox&GA for 0.7 and 1.1 modulation indexes Figure 5. 5-level inverter output voltage with SHE eliminating 3 rd order harmonic for 0.7 and  ... 
doi:10.18201/ijisae.97681 fatcat:fepmaow6d5d6nnodhd5nyk6lvm

Harmonic analysis and FPGA implementation of SHE controlled three phase CHB 11-level inverter in MV drives using deterministic and stochastic optimization techniques

Joshi Vesapogu, Sujatha Peddakotla, Seetha Rama Anjaneyulu Kuppa
2013 SpringerPlus  
Among all modulation control strategies for MLI, Selective harmonic elimination (SHE) technique is one of the traditionally preferred modulation control technique at fundamental switching frequency with  ...  Providing analytical solutions for SHE equations during the whole range of M I from 0 to 1, has been a challenging task for researchers.  ...  In order to solve SHE optimization problem, deterministic method like NR method, stochastic optimization methods like C-GA and MPSO techniques have been applied.  ... 
doi:10.1186/2193-1801-2-370 pmid:24010030 pmcid:PMC3757154 fatcat:7shcsxbjdndxbckqoavbacdota

A novel optimization harmonic elimination technique for cascaded multilevel inverter

Ezzidin Hassan Aboadla, Sheroz Khan, Mohamed H. Habaebi, Teddy Surya Gunawan, Belal A. Hamida, Mashkuri Bin Yaacob, Ali Aboadla
2019 Bulletin of Electrical Engineering and Informatics  
By calculating N switching angles, SHE technique can eliminate (N-1) low order odd harmonics of the output voltage waveform.  ...  Modulation index (m) and duty cycle play a big role in selective harmonic elimination technique to obtain a minimum harmonic distortion and desired fundamental component voltage.  ...  In this paper, optimization harmonic elimination method for cascaded multilevel inverters is investigated based on SHE technique.  ... 
doi:10.11591/eei.v8i2.1500 fatcat:sw52xq3pvfapnpi6agl2px47s4

Improved SHEPWM Strategy By The Robustness Optimization Algorithm In Multilevel Inverters With Equal DC Sources

Mahdi Vadizadeh
2014 IOSR Journal of Electrical and Electronics Engineering  
In the SHEPWM technique for multilevel inverters, in order to eliminate N-1 non-triplen odd harmonics of the AC-side voltage and to regulate the output line voltage amplitude, N switching angles need to  ...  In this paper a new robustness optimization algorithm is presented to elimination of selective low order harmonics (LOH) in the output line voltage of the multilevel inverter based on the Multi Population  ...  to eliminate first N-1 low order harmonics and control simultaneously the fundamental component.  ... 
doi:10.9790/1676-09448088 fatcat:cvufxhnvlng4dpkcbq27owys2e

Estimating the Fundamental Matrix Using Second-Order Cone Programming [chapter]

Min Yang
2011 Lecture Notes in Computer Science  
A single global minimum exists and it may be found by SOCP (Second-Order Cone Programming), which is a standard technique in convex optimization.  ...  A new method for the estimation of the fundamental matrix from point correspondences is presented. The minimization of the geometric error is performed based L-infinity norm minimization framework.  ...  Fundamental matrix estimation non-optimal methods use some simplified error criteria in order to obtain an estimate, often in closed form.  ... 
doi:10.1007/978-3-642-23896-3_72 fatcat:bo7gnof6j5do3ilghcsxbiej6q

Estimating the fundamental matrix via constrained least-squares: a convex approach

G. Chesi, A. Garulli, A. Vicino, R. Cipolla
2002 IEEE Transactions on Pattern Analysis and Machine Intelligence  
ACKNOWLEDGMENTS The authors would like to thank Richard Hartley for providing the image sequences he used in [7] .  ...  Problem (10) belongs to a class of optimizations problems for which convexification techniques have been recently developed [2] .  ...  Several techniques have been developed for the estimation of the fundamental matrix from point correspondences, like the linear criterion, the distance to epipolar lines criterion, and the gradient criterion  ... 
doi:10.1109/34.990139 fatcat:lw55tjcrhbh6lleyadsdxi2mg4

Elimination of Harmonics in Photovoltaic Seven-level Inverter with Newton-raphson Optimization

Krismadinata, Nasrudin Abd Rahim, Hew Wooi Ping, Jeyraj Selvaraj
2013 Procedia Environmental Sciences  
This paper describes a strategy to optimize the switching angle of a modified H-bridge single-phase seven-level inverter for stand-alone photovoltaic (PV) system.  ...  Optimized Harmonic Elimination Stepped Waveform (OHESW) technique was employed to improve the output waveform quality.  ...  Optimization technique based on Genetic Algorithm (GA) is proposed for computation of the switching angles for a seven-level inverter [3, 4] .  ... 
doi:10.1016/j.proenv.2013.02.067 fatcat:iyi5imhz3jca3cla22aktgiudy
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