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Photonic crystal fiber design by means of a.genetic algorithm

OPTICS EXPRESS 2004年第9期12卷 1990-1995页

作者： Kerrinckx, E Bigot, L Douay, M Quiquempois, Y Univ Lille 1 Lab Phys Lasers Atomes & Mol UMR 8523UFR Phys Inst Rech Composants Logiciels & Mat Informat Com F-59655 Villeneuve Dascq France

A.genetic algorithm (GA) is used to design photonic crystal fiber structures with user-defined chromatic dispersion properties. This GA is combined with a full vectorial finite element method in order to determine the effective index of propagation of the modes and then, the chromatic dispersion of structures generated by GA. This method proves to be a powerful tool for solving this inverse problem. (C) 2004 Optical Society of America.

关键词： .genetic algorithm inverse OPEX chromatic photonic crystal fibers fiber design

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Optimized design of two-pump fiber optical parametric amplifier with two-section nonlinear fibers using.genetic algorithm

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OPTICS EXPRESS 2004年第23期12卷 5603-5613页

作者： Gao, MY Jiang, C Hu, WS Wang, JY Shanghai Jiao Tong Univ State Key Lab Adv Opt Commun Syst & Networks Shanghai 200030 Peoples R China

A new two-pump fiber optical parametric amplifier (FOPA) is presented, which is composed of two-section high nonlinear fibers (HNLFs)..genetic algorithm (GA), a multivariate stochastic optimization algorithm is applied to optimize parameters of two fiber segments, such as the length and dispersion coefficient of fiber. A broadband FOPA with two-section HNLFs is obtained using optimum design parameters, which theoretically provides a uniform gain of 20.3 dB with 0.2-dB uniformity over a 346-nm bandwidth. (C) 2004 Optical Society of America.

关键词： .genetic algorithm optimize dispersion coefficient Parametric Amplifiers fiber segments nonlinear fibers HNLFs multivariate stochastic optimization broadband FOPA

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MMI devices with weak guiding designed in three dimensions using a.genetic algorithm

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OPTICS EXPRESS 2004年第12期12卷 2716-2722页

作者： West, BR Honkanen, S Univ Arizona Ctr Opt Sci Tucson AZ 85721 USA

We discuss the design of weakly guided multimode interference (MMI) devices using a.genetic algorithm. For devices exhibiting a non-negligible vertical waveguide offset, such as those produced using ion exchange in glass, three-dimensional modeling is required to properly evaluate the device performance. A combination of semivectorial finite difference modeling in two transverse dimensions and mode propagation analysis (MPA) in the propagation direction is used to evaluate the merit of each trial design. An example is provided of a 1 x 4 power splitter designed for ion exchange, which shows considerable improvement over that obtained by self-imaging theory. (C) 2004 Optical Society of America.

关键词： .genetic algorithm Lightwave Technol transverse difference merit self-imaging Ion exchange using genetic MMI devices power splitter multimode interference couplers

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Design of multilayer antireflection coatings made from co-sputtered and low-refractive-index materials by.genetic algorithm

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OPTICS EXPRESS 2008年第8期16卷 5290-5298页

作者： Schubert, Martin F. Mont, Frank W. Chhajed, Sameer Poxson, David J. Kim, Jong Kyu Schubert, E. Fred Rensselaer Polytech Inst Future Chips Constellat Dept Elect Comp & Syst Engn Troy NY 12180 USA Rensselaer Polytech Inst Dept Phys Appl Phys & Astron Troy NY 12180 USA

Designs of multilayer antireflection coatings made from co-sputtered and low-refractive-index materials are optimized using a.genetic algorithm. Co-sputtered and low-refractive-index materials allow the fine-tuning of refractive index, which is required to achieve optimum antireflection characteristics. The algorithm minimizes reflection over a wide range of wavelengths and incident angles, and includes material dispersion. Designs of antireflection coatings for silicon-based image sensors and solar cells, as well as triple-junction GaInP/GaAs/Ge solar cells are presented, and are shown to have significant performance advantages over conventional coatings. Nano-porous low-refractive-index layers are found to comprise generally half of the layers in an optimized antireflection coating, which underscores the importance of nano-porous layers for high-performance broadband and omnidirectional antireflection coatings. (C) 2008 Optical Society of America.

关键词： .genetic algorithm half image sensors SOLAR CELLS Rensselaer Polytechnic low-refractive-index Nano-porous triple-junction multilayer antireflection coatings optimized antireflection

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genetic algorithm for scheduling of laboratory personnel

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CLINICAL CHEMISTRY 2001年第1期47卷 118-123页

作者： Boyd, JC Savory, J Univ Virginia Hlth Syst Dept Pathol Charlottesville VA 22908 USA

Background: Staffing core laboratories with appropriate skilled workers requires a process to schedule these individuals so that all workstations are appropriately filled and all the skills of each worker are exercised periodically to maintain competence. Methods: We applied a.genetic algorithm to scheduling laboratory personnel. Our program, developed in Visual Basic 4.0, maximizes the value of a fitness function that measures how well a given scheduling of individuals and their skills matches a set of work tasks for a given work shift. The user provides in an Excel spreadsheet the work tasks, individuals available to work on any given date, and skills each individual possesses. The user also specifies the work shift to be scheduled, the range of dates to be scheduled, the number of days that an individual stays on a given workstation before rotating, and various parameters for the.genetic algorithm if they differ from the default values. Results: For >22 months, the program matched individuals to those tasks for which they were qualified and maintained personnel skills by rotating job duties. The schedules generated by the program allowed supervisory personnel to anticipate dates far in advance of when worker availability would be limited, so staffing could be adjusted. In addition, the program helped to identify skills for which too few individuals had been trained. This program has been well accepted by the staff in the clinical laboratories of a 670-bed university medical center, saving 37 h of labor per month, or approximately $11 000 per year, in time that supervisory personnel have spent developing work schedules. Conclusions: The.genetic algorithm approach appears to be useful for scheduling in highly technical work environments that employ multiskilled workers. (C) 2001 American Association for Clinical Chemistry.

关键词： .genetic algorithm schedule worker fitness function scheduling workstations Laboratory Personnel Visual Basic

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Efficient algorithm and optimization for broadband Raman amplifiers

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OPTICS EXPRESS 2004年第4期12卷 564-573页

作者： Liu, XM Li, YH Tsing Hua Univ Dept Elect Engn Beijing 100084 Peoples R China

A hybrid.genetic algorithm (HGA) assisted by stochastic perturbation and the adaptive technique is proposed. Compared with our previous reports, the proposed HGA can exploit better solutions and greatly shorten the amount of run time. An example shows that the design of multipump Raman amplifiers involves the multimodal function optimization problem with multiple variables. With the new HGA, relationships of the optimal signal bandwidth with the span length and the ON-OFF Raman gain are obtained. A movie demonstrates the detailed interaction in pump-to-signal and signal-to-signal procedures. The corresponding optical signal-to-noise ratio of optimal results is obtained. (C) 2004 Optical Society of America.

关键词： .genetic algorithm greatly on-off run time optimal results Optimal Signal Raman amplifiers stochastic perturbation adaptive technique previous reports design of multipump new HGA span length pump-to-signal signal-to-signal

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Multi-objective and constrained design of fibre Bragg gratings using evolutionary algorithms

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OPTICS EXPRESS 2005年第19期13卷 7350-7364页

作者： Manos, S Poladian, L Univ Sydney Opt Fibre Technol Ctr Australian Photon CRC Sydney NSW 2006 Australia Univ Sydney Sch Phys Sydney NSW 2006 Australia Univ Sydney Sch Math & Stat Sydney NSW 2006 Australia

We apply a multi-objective evolutionary algorithm to a grating problem where only very specific features of the transmission spectrum are specified during the optimisation process. The design problem analysed here relates to the passive extraction of 10 GHz clock signals from a 10 Gbps OTDM RZ encoded data stream. Four spectral features of interest such as bandwidth and passband quality are explicitly defined. Using a real-encoded evolutionary algorithm along with an elitist multi-objective selection method, we arrive at a group of solutions which each satisfy the objectives to various degrees in the presence of manufacturing and other design constraints. (c) 2005 Optical Society of America.

关键词： .genetic algorithm inverse selection satisfy Extraction OTDM degrees Objectives optical fibre data stream design problem using Evolutionary

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Inverse designed photonic crystal de-multiplex waveguide coupler

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OPTICS EXPRESS 2005年第14期13卷 5440-5449页

作者： Håkansson, A Sánchez-Dehesa, J Univ Politecn Valencia Nanophoton Technol Ctr Wave Phenomena Grp E-46022 Valencia Spain

A two-dimensional photonic crystal diplexer integrated with a waveguide coupler is proposed. The design is computer generated through an inverse design process, limited within an area measuring 5 mu m x 5 mu m. The best working device was designed for the optical communication wavelengths, 1.50 mu m and 1.55 mu m, i.e. a channel spacing of 50 nm. The device exhibits crosstalks suppressed below 40dB and coupling efficiencies close to 80%, for both channels. (C) 2005 Optical Society of America.

关键词： .genetic algorithm two-dimensional waveguide coupler de-multiplex inverse design

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WEIGHTS OPTIMIZATION OF NEURAL NETWORK VIA IMPROVED BCO APPROACH

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PROGRESS IN ELECTROMAGNETICS RESEARCH-PIER 2008年 83卷 185-198页

作者： Zhang, Y. Wu, L. Southeast Univ Sch Informat Sci & Engn Nanjing Peoples R China

Feed forward neural Network (FNN) has been widely applied to many fields because of its ability to closely approximate unknown function to any degree of desired accuracy. Back Propagation (BP) is the most general learning algorithms, but is subject to local optimal convergence and poor performance even on simple problems when forecasting out of samples. Thus, we proposed an improved Bacterial Chemotaxis Optimization (BCO) approach as a possible alternative to the problematic BP algorithm, along with a novel adaptive search strategy to improve the efficiency of the traditional BCO. Taking the classical XOR problem and sinc function approximation as examples, comparisons were implemented. The results demonstrate that our algorithm is obviously superior in convergence rate and precision compared with other training algorithms, such as.genetic algorithm (GA) and Taboo Search (TS).

关键词： .genetic algorithm widely sinc RBF FUNCTION APPROXIMATION bacterial XOR chemotaxis FNN BP algorithm IMPROVED BCO

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A SIMPLE ALTERNATIVE FOR BEAM RECONFIGURATION OF ARRAY ANTENNAS

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PROGRESS IN ELECTROMAGNETICS RESEARCH-PIER 2008年 88卷 227-240页

作者： Ares, F. Franceschetti, G. Rodriguez, J. A. Univ Santiago Compostela Dept Appl Phys Santiago De Compostela 15782 Spain Univ Calif Los Angeles Los Angeles CA USA Univ Naples Federico 2 Dept Elect Engn I-80125 Naples Italy

An innovative method for antenna arrays beam configuration is presented. In the proposed method, every element of the array is connected to its feed through a switch, so that it can be active or passive, depending on the switch position. Pattern reconfigurability is achieved by appropriately switching on or off the array elements. The optimal configuration of the switches for each of the radiated patterns, as well the common voltages of the active elements, is calculated by using a.genetic algorithm. For each configuration, the currents in the driven and parasitic elements are determined, via their self and mutual impedances, by inversion of the impedance matrix. In the presented examples, the method has been applied to both linear and planar arrays of parallel dipoles that switch the power pattern from a pencil to a foot-topped beam (linear array) or to a footprint pattern (planar array).

关键词： .genetic algorithm antenna arrays impedances gurability footprint DIPOLES at-topped Pattern recon driven and parasitic

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