10,144 research outputs found
Self-adaptation of Genetic Operators Through Genetic Programming Techniques
Here we propose an evolutionary algorithm that self modifies its operators at
the same time that candidate solutions are evolved. This tackles convergence
and lack of diversity issues, leading to better solutions. Operators are
represented as trees and are evolved using genetic programming (GP) techniques.
The proposed approach is tested with real benchmark functions and an analysis
of operator evolution is provided.Comment: Presented in GECCO 201
Analisis dan penilaian prestasi lengah lepas tangan menggunakan protokol pencetusan sesi (SIP) bagi sistem terintegrasi UMTS-WLAN
Teknologi rangkaian tanpa vvayar 4G merupakan penggabungan beberapa teknologi
rangkaian capaian yang berbeza seperti rangkaian Universal Mobile
Telecommunication System (UMTS) dan Rangkaian Kawasan Setempat Tanpa Wayar
(WLAN). Rangkaian 4G menyokong mobiliti tanpa kelim {seamless) dalam
menjanjikan perhubungan dan perkhidmatan yang terbaik kepada pelanggan. Protokol
Pencetusan Sesi (SIP) yang berada pada lapisan aplikasi telah diramalkan sebagai
calon terbaik bagi menguruskan mobiliti di dalam rangkaian 4G. Rangkaian 4G yang
menawarkan aplikasi multimedia dalam perkhidmatannya mesti mempunyai lengah
lepas tangan yang rendah bagi mencapai objektif penubuhannya. Tujuan utama
disertasi ini adalah untuk menilai lengah lepas tangan bagi sistem terintegrasi UMTSWLAN
yang menggunakan SIP sebagai protokol pengisyaratan. Model simulasi
menggunakan MATLAB dibangunkan untuk menilai prestasi lengah lepas tangan
tersebut. Model simulasi menggambarkan pergerakan hos mobil ke rangkaian UMTS
dan WLAN. Lengah lepas tangan yang berlaku diukur berdasarkan model analitik.
Prestasi lengah lepas tangan dinilai berdasarkan perubahan kadar ralat kerangka
(FER), kadar ketibaan sesi SIP dan halaju hos mobil (MIT) semasa MH bergerak ke
rangkaian UMTS dan WLAN. Keputusan simulasi menunjukkan bahawa lengah lepas
tangan meningkat dengan penambahan FER dan kadar ketibaan sesi SIP. Halaju
kebolehgerakan pengguna memberi kesan terhadap nilai lengah lepas tangan.
Keputusan juga menunjukkan lengah lepas tangan minimum yang berlaku sewaktu
MH bergerak ke rangkaian UMTS adalah 1.9565 saat dengan lebar jalur saluran
128kbps dan ke rangkaian WLAN adalah sekitar 0.8651 saat dengan lebar jalur
saluran 11 Mbps. Berdasarkan nilai ini, lengah lepas tangan semasa MH bergerak ke
rangkaian UMTS atau WLAN adalah tidak boleh diterima untuk penjurusan
multimedia. Di dalam kajian ini didapati capaian tanpa wayar GPRS menyumbang
lengah terbesar daripada keseluruhan lengah lepas tangan ke rangkaian UMTS
Multi-population methods with adaptive mutation for multi-modal optimization problems
open access journalThis paper presents an efficient scheme to locate multiple peaks on multi-modal optimization problems by using genetic algorithms (GAs). The premature convergence problem shows due to the loss of diversity, the multi-population technique can be applied to maintain the diversity in the population and the convergence capacity of GAs. The proposed scheme is the combination of multi-population with adaptive mutation operator, which determines two different mutation probabilities for different sites of the solutions. The probabilities are updated by the fitness and distribution of solutions in the search space during the evolution process. The experimental results demonstrate the performance of the proposed algorithm based on a set of benchmark problems in comparison with relevant algorithms
Genetic algorithms: a tool for optimization in econometrics - basic concept and an example for empirical applications
This paper discusses a tool for optimization of econometric models based on genetic algorithms. First, we briefly describe the concept of this optimization technique. Then, we explain the design of a specifically developed algorithm and apply it to a difficult econometric problem, the semiparametric estimation of a censored regression model. We carry out some Monte Carlo simulations and compare the genetic algorithm with another technique, the iterative linear programming algorithm, to run the censored least absolute deviation estimator. It turns out that both algorithms lead to similar results in this case, but that the proposed method is computationally more stable than its competitor. --Genetic Algorithm,Semiparametrics,Monte Carlo Simulation
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