COMPARING MINIMUM NEIGHBORHOOD EVALUATION SCHEMES FOR FINDING SPATIALLY ROBUST SOLUTIONS

2007 ◽  
Vol 17 (03) ◽  
pp. 299-309
Author(s):  
GRZEGORZ DRZADZEWSKI ◽  
MARK WINEBERG

The common definition for robust solutions considers a solution robust if it remains optimal when the parameters defining the fitness function are perturbed. A second definition that can be found in the literature: robustness occurs when a solution can be varied spatially without a significant drop in fitness. We propose an alternative operational definition for spatial robustness: both the solution and the neighbourhood around the solution has fitness above a given threshold. With this new definition, we created a set of functions with useful properties to allow for the testing of solution robustness. The performance of a Genetic Algorithm (GA) is then evaluated based on its ability to identify multiple robust solutions based on the above robustness definition. Different neighbourhood evaluation schemes are identified from the literature and compared, with the minimum neighbour technique proving to be the most effective.

2007 ◽  
Vol 17 (03) ◽  
pp. 311-321
Author(s):  
GRZEGORZ DRZADZEWSKI ◽  
MARK WINEBERG

The common definition for robust solutions considers a solution robust if it remains optimal (or near optimal) when the parameters defining the fitness function are perturbed. We call this parameter robustness or temporal robustness. In this paper we propose an alternate definition for robustness, which we call spatial or solution robustness, if both the solution and the neighbourhood around the solution has high fitness. With this definition, we created a set of functions with useful properties to allow for the testing of solution robustness. We then focus on the effect of the precision (density) of the search space and find that it has a drastic effect on both the number of solutions and their quality.


Author(s):  
Avtandil kyzy Ya

Abstract: This paper highlights similarities and different features of the category of kinesics “hand gestures”, its frequency usage and acceptance by different individuals in two different cultures. This study shows its similarities, differences and importance of the gestures, for people in both cultures. Consequently, kinesics study was mentioned as a main part of body language. As indicated in the article, the study kinesics was not presented in the Kyrgyz culture well enough, though Kyrgyz people use hand gestures a lot in their everyday life. The research paper begins with the common definition of hand gestures as a part of body language, several handshake categories like: the finger squeeze, the limp fish, the two-handed handshake were explained by several statements in the English and Kyrgyz languages. Furthermore, this article includes definitions and some idioms containing hand, shake, squeeze according to the Oxford and Academic Dictionary to show readers the figurative meanings of these common words. The current study was based on the books of writers Allan and Barbara Pease “The definite book of body language” 2004, Romana Lefevre “Rude hand gestures of the world”2011 etc. Key words: kinesics, body language, gestures, acoustics, applause, paralanguage, non-verbal communication, finger squeeze, perceptions, facial expressions. Аннотация. Бул макалада вербалдык эмес сүйлѳшүүнүн бѳлүгү болуп эсептелген “колдордун жандоо кыймылы”, алардын эки башка маданиятта колдонулушу, айырмачылыгы жана окшош жактары каралган. Макаланын максаты болуп “колдордун жандоо кыймылынын” мааниси, айырмасы жана эки маданиятта колдонулушу эсептелет. Ошону менен бирге, вербалдык эмес сүйлѳшүүнүн бѳлүгү болуп эсептелген “кинесика” илими каралган. Берилген макалада кѳрсѳтүлгѳндѳй, “кинесика” илими кыргыз маданиятында толугу менен изилденген эмес, ошого карабастан “кинесика” илиминин бѳлүгү болуп эсептелген “колдордун жандоо кыймылы” кыргыз элинин маданиятында кѳп колдонулат. Андан тышкары, “колдордун жандоо кыймылынын” бир нече түрү, англис жана кыргыз тилдеринде ма- селен аркылуу берилген.Тѳмѳнкү изилдѳѳ ишин жазууда чет элдик жазуучулардын эмгектери колдонулду. Түйүндүү сѳздѳр: кинесика, жандоо кыймылы, акустика,кол чабуулар, паралингвистика, вербалдык эмес баарлашуу,кол кысуу,кабыл алуу сезими. Аннотация. В данной статье рассматриваются сходства и различия “жестикуляции” и частота ее использования, в американской и кыргызской культурах. Следовательно, здесь было упомянуто понятие “кинесика” как основная часть языка тела. Как указано в статье, “кинесика” не была представлена в кыргызской культуре достаточно хорошо, хотя кыргызский народ часто использует жестикуляцию в повседневной жизни. Исследовательская работа начинается с общего определения “жестикуляции” как части языка тела и несколько категорий жестикуляции, таких как: сжатие пальца, слабое рукопожатие, рукопожатие двумя руками, были объяснены несколькими примерами на английском и кыргызском языках. Кроме того, эта статья включает определения слов “рука”, “рукопожатие”, “сжатие” и некоторые идиомы, содержащие данных слов согласно Оксфордскому и Академическому словарю, чтобы показать читателям их образное значение. Данное исследование было основано на книгах писателей Аллана и Барбары Пиз «Определенная книга языка тела» 2004 года, Романа Лефевра «Грубые жестикуляции мира» 2011 года и т.д. Ключевые слова: кинесика, язык жестов, жесты, акустика, аплодисменты, паралингвистика, невербальная коммуникация, сжатие пальца, чувство восприятия, выражение лиц.


Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 115
Author(s):  
Andriy Chaban ◽  
Marek Lis ◽  
Andrzej Szafraniec ◽  
Radoslaw Jedynak

Genetic algorithms are used to parameter identification of the model of oscillatory processes in complicated motion transmission of electric drives containing long elastic shafts as systems of distributed mechanical parameters. Shaft equations are generated on the basis of a modified Hamilton–Ostrogradski principle, which serves as the foundation to analyse the lumped parameter system and distributed parameter system. They serve to compute basic functions of analytical mechanics of velocity continuum and rotational angles of shaft elements. It is demonstrated that the application of the distributed parameter method to multi-mass rotational systems, that contain long elastic elements and complicated control systems, is not always possible. The genetic algorithm is applied to determine the coefficients of approximation the system of Rotational Transmission with Elastic Shaft by equivalent differential equations. The fitness function is determined as least-square error. The obtained results confirm that application of the genetic algorithms allow one to replace the use of a complicated distributed parameter model of mechanical system by a considerably simpler model, and to eliminate sophisticated calculation procedures and identification of boundary conditions for wave motion equations of long elastic elements.


Mathematics ◽  
2021 ◽  
Vol 9 (13) ◽  
pp. 1581
Author(s):  
Alfonso Hernández ◽  
Aitor Muñoyerro ◽  
Mónica Urízar ◽  
Enrique Amezua

In this paper, an optimization procedure for path generation synthesis of the slider-crank mechanism will be presented. The proposed approach is based on a hybrid strategy, mixing local and global optimization techniques. Regarding the local optimization scheme, based on the null gradient condition, a novel methodology to solve the resulting non-linear equations is developed. The solving procedure consists of decoupling two subsystems of equations which can be solved separately and following an iterative process. In relation to the global technique, a multi-start method based on a genetic algorithm is implemented. The fitness function incorporated in the genetic algorithm will take as arguments the set of dimensional parameters of the slider-crank mechanism. Several illustrative examples will prove the validity of the proposed optimization methodology, in some cases achieving an even better result compared to mechanisms with a higher number of dimensional parameters, such as the four-bar mechanism or the Watt’s mechanism.


Symmetry ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 18
Author(s):  
Yan Li ◽  
Jing He ◽  
Youxi Wu ◽  
Rongjie Lv

The real world can be characterized as a complex network sto in symmetric matrix. Community discovery (or community detection) can effectively reveal the common features of network groups. The communities are overlapping since, in fact, one thing often belongs to multiple categories. Hence, overlapping community discovery has become a new research hotspot. Since the results of the existing community discovery algorithms are not robust enough, this paper proposes an effective algorithm, named Two Expansions of Seeds (TES). TES adopts the topological feature of network nodes to find the local maximum nodes as the seeds which are based on the gravitational degree, which makes the community discovery robust. Then, the seeds are expanded by the greedy strategy based on the fitness function, and the community cleaning strategy is employed to avoid the nodes with negative fitness so as to improve the accuracy of community discovery. After that, the gravitational degree is used to expand the communities for the second time. Thus, all nodes in the network belong to at least one community. Finally, we calculate the distance between the communities and merge similar communities to obtain a less- undant community structure. Experimental results demonstrate that our algorithm outperforms other state-of-the-art algorithms.


2010 ◽  
Vol 19 (01) ◽  
pp. 107-121 ◽  
Author(s):  
JUAN CARLOS FIGUEROA GARCÍA ◽  
DUSKO KALENATIC ◽  
CESAR AMILCAR LÓPEZ BELLO

This paper presents a proposal based on an evolutionary algorithm for imputing missing observations in time series. A genetic algorithm based on the minimization of an error function derived from their autocorrelation function, mean, and variance is presented. All methodological aspects of the genetic structure are presented. An extended description of the design of the fitness function is provided. Four application examples are provided and solved by using the proposed method.


Author(s):  
Sourav Kundu ◽  
Kentaro Kamagata ◽  
Shigeru Sugino ◽  
Takeshi Minowa ◽  
Kazuto Seto

Abstract A Genetic Algorithm (GA) based approach for solution of optimal control design of flexible structures is presented in this paper. The method for modeling flexible structures with distributed parameters as reduced-order models with lumped parameters, which has been developed previously, is employed. Due to some restrictions on controller design it is necessary to make a reduced-order model of the structure. Once the model is established the design of flexible structures is considered as a feedback search procedure where a new solution is assigned some fitness value for the GA and the algorithm iterates till some satisfactory design solution is achieved. We propose a pole assignment method to determine the evaluation (fitness) function to be used by the GA to find optimal damping ratios in passive elements. This paper demonstrates the first results of a genetic algorithm approach to solution of the vibration control problem for practical control applications to flexible tower-like structures.


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