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Some New Results on Bicomplex Bernstein Polynomials

Seda Karateke | Cigdem Atakut | Oezge Ozalp Guller | Carlo Cattani

Makale | 2021 | MDPI

The aim of this work is to consider bicomplex Bernstein polynomials attached to analytic functions on a compact C2-disk and to present some approximation properties extending known approximation results for the complex Bernstein polynomials. Furthermore, we obtain and present quantitative estimate inequalities and the Voronovskaja-type result for analytic functions by bicomplex Bernstein polynomials.

Beta irradiation effects on impedance spectra of electrospun PEDOT:PSS nanofibres

Yalcin Urfa | Ahmet Altindal


Poly(3,4-ethylenedioxythio-phene):poly(styrenesulphonate) (PEDOT:PSS) nanofibres were first prepared via electrospinning method. Microstructural arrangement of the nanofibres was investigated by scanning electron microscopy technique. Then, the effect of beta irradiation with different absorbed doses on their impedance spectra were investigated in the frequency range from 5 to 13 x 10(6). It was observed that beta irradiation leads to a considerable decrease in both real and imaginary parts of the complex dielectric function, and alternating current conductivity of the nanofibres. The obtained frequency dependent conductivity data w . . .ere discussed in terms of pair approximation. It was established that, for all beta irradiation doses, the frequency dependence of the conductivity is characterized by the presence of four frequency regions with different slopes. Analysis of the impedance data revealed that chain scission via chain cross-linking and free radical formation are most likely mechanisms for changes in impedance parameters. Two clear semicircles in Nyquist plot have been successfully explained by employing two parallel R-CPE equivalent circuits in series configuration. An overall evaluation of the obtained data indicates that electrospun PEDOT:PSS nanofibres have great potential for the development of highly sensitive impedance-based beta radiation sensor Daha fazlası Daha az

Automated evaluation of Cr-III coated parts using Mask RCNN and ML methodse

Metin Zontul | Esra Kavalci Yilmaz | Oguz Kaynar | Ramazan Katirci


In this study, chrome coatings were carried out using a Cr-III electroplating bath. The coated parts were classified depending on their appearance. A new approach was developed to classify the coated parts automatically using artificial intelligence methods. Mask RCNN and machine learning (ML) methods such as Multilayer Perceptron (MLP), Support Vector Classifier (SVC), Gaussian Process (GP), K-nearest Neighbors (KNN), XGBoost, and Random Forest Classifier (RFC) were used together. Mask RCNN was used to clean the coated parts from the redundant data. The extracted data were flattened and converted to the row vectors for use as input . . . in ML methods. ML algorithms were used to classify the coated parts as Pass and Fail. The classification accuracy was checked with the leave one out (loo) cross-validation method. RFC method gave the highest accuracy, 0.83, and F1 score, 0.88. The accuracy of Mask RCNN was checked using a dataset of separated validation images. It was observed that extracting the unnecessary data from the images increased the accuracy exceedingly. Moreover, the method exhibits a high potential to keep the parameters of the electroplating process under control Daha fazlası Daha az

Cross-cultural aspects of tourism and hospitality: a services marketing and management perspective, 1st edition

Derya Demirdelen Alrawadieh


Cross-Cultural Aspects of Tourism and Hospitalityauthored by Erdogan Koc makes a timely andsignificant contribution not only to tourism and hospitality research but also to cross-culturaltheory. This elegant book involves 13 chapters and is supplemented with 15figures, 51 tables,and a comprehensive index. Each chapter provides important insights into the cross-culturalaspects of the tourism and hospitality industry. Each chapter begins with a set of learningobjectives showing what the reader is expected to know after reading the chapter. Theauthor is also to be acclaimed for enriching each chapter with activities, exercises, and cas . . .estudies that can potentially contribute to a better understanding of the theoretical conceptsdiscussed in the text. Each chapter concludes with questions, recommended references forfurther reading, and research ideas for further development. The latter point makes thiswork valuable not only for undergraduate and postgraduate students but also for prospectivetourism and hospitality researchers and academicians who are interested in cross-culturalresearch. Overall, the book is a valuable reference that would attract a wide readership fromthefield of tourism and hospitality Daha fazlası Daha az

Inside out, exploring residential spaces during COVID-19 lockdown from the perspective of architecture students

Paria Valizadeh | Aminreza Iranmanesh


The new preventative measures that have emerged from the Coronavirus crisis brought about changes in different aspects of daily life. Some of these changes may have a significant impact on how the built environment is being experienced. The current paper examines reconfigurations that happened in residential spaces and space allocations for transitioned activities in a small case study targeting a group of architecture students in Cyprus. Analysis and findings are structured in three sections, indoor activities, special organization, and quality of life. The result shows blurring boundaries between public and private activities. In . . .terms of spatial configuration, in-between spaces such as balconies and openings become central in designing residential units. Moreover, the study finds that the successful transition of work, education, exercise, and remote social interactions into the housing unit is the best predictor of reported quality of life under quarantine. It is unclear which parts of newly emerged measures will last even beyond the end of the pandemic however, developing new insights into COVID-19's impacts on living environments can help to introduce design responses that improve quality of life by creating better residential environments in the post-pandemic world where the remoteness of many daily activities is becoming the norm Daha fazlası Daha az

Adapted-RRT: novel hybrid method to solve three-dimensional path planning problem using sampling and metaheuristic-based algorithms

Mohammed Ahmed Shah


Three-dimensional path planning for autonomous robots is a prevalent problem in mobile robotics. This paper presents three novel versions of a hybrid method designed to assist in planning such paths for these robots. In this paper, an improvement on Rapidly exploring Random Tree (RRT) algorithm, namely Adapted-RRT, is presented that uses three well-known metaheuristic algorithms, namely Grey Wolf Optimization (GWO), Incremental Grey Wolf Optimization (I-GWO), and Expanded Grey Wolf Optimization (Ex-GWO)). RRT variants, using these algorithms, are named Adapted-RRTGWO, Adapted-RRTI-GWO, and Adapted-RRTEx-GWO. The most significant sho . . .rtcoming of the methods in the original sampling-based algorithm is their inability in finding the optimal paths. On the other hand, the metaheuristic-based algorithms are disadvantaged as they demand a predetermined knowledge of intermediate stations. This study is novel in that it uses the advantages of sampling and metaheuristic methods while eliminating their shortcomings. In these methods, two important operations (length and direction of each movement) are defined that play an important role in selecting the next stations and generating an optimal path. They try to find solutions close to the optima without collision, while providing comparatively efficient execution time and space complexities. The proposed methods have been simulated employing four different maps for three unmanned aerial vehicles, with diverse sets of starting and ending points. The results have been compared among a total of 11 algorithms. The comparison of results shows that the proposed path planning methods generally outperform various algorithms, namely BPIB-RRT, tGSRT, GWO, I-GWO, Ex-GWO, PSO, Improved BA, and WOA. The simulation results are analysed in terms of optimal path costs, execution time, and convergence rate Daha fazlası Daha az

Evaluation of Multi-Objective Optimization Algorithms for NMR Chemical Shift Assignment

Emel Maden Yilmaz | Peter Guntert | Sima Etaner-Uyar

Makale | 2021 | MDPI

An automated NMR chemical shift assignment algorithm was developed using multi-objective optimization techniques. The problem is modeled as a combinatorial optimization problem and its objective parameters are defined separately in different score functions. Some of the heuristic approaches of evolutionary optimization are employed in this problem model. Both, a conventional genetic algorithm and multi-objective methods, i.e., the non-dominated sorting genetic algorithms II and III (NSGA2 and NSGA3), are applied to the problem. The multi-objective approaches consider each objective parameter separately, whereas the genetic algorithm . . . followed a conventional way, where all objectives are combined in one score function. Several improvement steps and repetitions on these algorithms are performed and their combinations are also created as a hyper-heuristic approach to the problem. Additionally, a hill-climbing algorithm is also applied after the evolutionary algorithm steps. The algorithms are tested on several different datasets with a set of 11 commonly used spectra. The test results showed that our algorithm could assign both sidechain and backbone atoms fully automatically without any manual interactions. Our approaches could provide around a 65 success rate and could assign some of the atoms that could not be assigned by other methods Daha fazlası Daha az

Hybrid algorithms based on combining reinforcement learning and metaheuristic methods to solve global optimization problems

Mohammed Ahmed Shah | Royal Aliyev | Farzad Kiani | Murat Ugur Gulle | Hasan Basyildiz | Mohammed Ahmed Shah

Makale | 2021 | ELSEVIER

This paper introduces three hybrid algorithms that help in solving global optimization problems using reinforcement learning along with metaheuristic methods. Using the algorithms presented, the search agents try to find a global optimum avoiding the local optima trap. Compared to the classical metaheuristic approaches, the proposed algorithms display higher success in finding new areas as well as exhibiting a more balanced performance while in the exploration and exploitation phases. The algorithms employ reinforcement agents to select an environment based on predefined actions and tasks. A reward and penalty system is used by the . . .agents to discover the environment, done dynamically without following a predetermined model or method. The study makes use of Q-Learning method in all three metaheuristic algorithms, so-called RLI-GWO, RLEx-GWO, and RLWOA algorithms, so as to check and control exploration and exploitation with Q-Table. The Q-Table values guide the search agents of the metaheuristic algorithms to select between the exploration and exploitation phases. A control mechanism is used to get the reward and penalty values for each action. The algorithms presented in this paper are simulated over 30 benchmark functions from CEC 2014, 2015 and the results obtained are compared with well-known metaheuristic and hybrid algorithms (GWO, RLGWO, I-GWO, Ex-GWO, and WOA). The proposed methods have also been applied to the inverse kinematics of the robot arms problem. The results of the used algorithms demonstrate that RLWOA provides better solutions for relevant problems. (C) 2021 Elsevier B.V. All rights reserved Daha fazlası Daha az

Gamma ray irradiation dose dependent methanol sensing with ZnO nanoparticles

Yalcin Urfa | Vahit Corumlu | Ahmet Altindal


This study reports the influence of gamma ray irradiation of various doses in the range of 1?150 kGy on methanol sensing performance and adsorption kinetics of ZnO nanoparticles based sensors. ZnO nanoparticles were synthesized via sol-gel method and characterized with X-ray diffraction (XRD), transmission electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR) techniques. The results revealed that the methanol sensing performance of ZnO nanoparticles based sensor including sensitivity, response and recovery times improved by the gamma ray irradiation. Additionally, Elovich equation, Ritchie?s equation and pseu . . .do first order model were selected to follow the methanol adsorption process. The preliminary result of the methanol adsorption kinetic studies revealed that the adsorption kinetics strongly depends on the gamma irradiation dose. Among other kinetic models investigated, the pseudo first-order equation was the best to describe the adsorption kinetics of methanol on ZnO nanoparticles up to 50 kG dose of gamma ray, as evidenced by the highest correlation coefficients. On the other hand, for higher doses than of 50 kGy of gamma irradiation, our analysis showed that Elovich equation generates a straight line that best fit to methanol adsorption data on ZnO nanoparticles Daha fazlası Daha az

Sexual harassment, psychological well-being, and job satisfaction of female tour guides: the effects of social and organizational support

Zaid Alrawadieh | Derya Demirdelen Alrawadieh | Hossein G. T. Olya | Gul Erkol Bayram | Onur Cuneyt Kahraman


Drawing on the Conservation of Resources Theory (COR), and a gender perspective, this study proposes and tests a conceptual model postulating relationships between sexual harassment, burnout, perceived social and organizational support, psychological well-being, and job satisfaction. A survey of Turkish female tour guides resulted in 221 valid questionnaires. The results reveal that female tour guides' sexual harassment experience has a negative impact on their job satisfaction and psychological well-being. Unlike perceived social support, perceived organizational support plays a significant and negative role in triggering sexual ha . . .rassment. The findings also confirm the mediating effects of burnout on the relationship between sexual harassment and job satisfaction as well as the relationship between sexual harassment and psychological well-being. The study contributes to gender equality and sustainability research and offers several practical implications for stakeholders in the travel industry and public policy Daha fazlası Daha az

3D Path Planning Method for Multi-UAVs Inspired by Grey Wolf Algorithms

Mohammed Ahmed Shah


Efficient and collision-free pathfinding, between source and destination locations for multi-Unmanned Aerial Vehicles (UAVs), in a predefined environment is an important topic in 3D Path planning methods. Since path planning is a Non-deterministic Polynomial-time (NP-hard) problem, metaheuristic approaches can be applied to find a suitable solution. In this study, two efficient 3D path planning methods, which are inspired by Incremental Grey Wolf Optimization (I-GWO) and Expanded Grey Wolf Optimization (Ex-GWO), are proposed to solve the problem of determining the optimal path for UAVs with minimum cost and low execution time. The p . . .roposed methods have been simulated using two different maps with three UAVs with diverse sets of starting and ending points. The proposed methods have been analyzed in three parameters (optimal path costs, time and complexity, and convergence curve) by varying population sizes as well as iteration numbers. They are compared with well-known different variations of grey wolf algorithms (GWO, mGWO, EGWO, and RWGWO). According to path cost results of the defined case studies in this study, the I-GWO-based proposed path planning method (PPI-GWO) outperformed the best with 36.11. In the other analysis parameters, this method also achieved the highest success compared to the other five methods Daha fazlası Daha az


Paria Valizadeh


Modernization programs in Iran emerged with the 1963 White Revolution and transformed the socio-spatial organization of the capital city of Tehran. This modernization was associated with Westernization and led to uneven urban development, exacerbated class divisions and developed a kind of fetishism of urbanization in the Iranian society of 1970s. Modernizing the society in the image of the west and in particular the United States fascinated the upper classes since they could afford to live in the ways described in the media, and the more their fascination with the westernized way of living developed, the more they become alienated . . .from the rest of society. This study conducts a critical analysis of the impacts of modernization in the image of the west, notably in the domain of housing as one of the crucial geographical materialization in Tehran. The study will examine the link between modernization and westernization through spatial representations of case studies from both rich and poor within Tehran. It is expected that the ongoing study help to get a broader understanding of the impacts of fetishism of urbanization focusing on residential architecture, and pursuing an improved-place image as mainstream Iranian modernization on the urban landscape of Tehran in the 1960s and 1970s Daha fazlası Daha az

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