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The purpose of this study is to guarantee assembly quality and reduce the number of manufacturing cycles required for an reflector of the large reflector antenna. An optimal approach combining a finite element method (FEM) with a genetic algorithm (GA) is developed to simulate and optimize reflector assembly before the assembly stage.

The chromosomes of GA are encoded with the consideration of the factors that affect the assembly of reflector. The fitness function of the GA consists of the assembly accuracy obtained from simulation, with evaluation of the assembly time consumption and labor cost. The algorithm will terminate when the GA is finished or the simulation results meet the permissible accuracy. Taking the assembly process of the reflector into account, an FEM based on a “life – death element” technique is introduced to quickly and precisely simulate reflector assembly.

A case study is presented, to which the proposed approach is applied. The results of finite element simulation demonstrate that the proposed FEM can simulate the reflector assembly process with oversimplified modeling and accurate simulation results. The optimal approach provides an accurate and efficient method for reflector assembly sequence planning indicated by the comparison of the measurements and calculation results.

The results also demonstrate that the proposed approach has practical significance for guiding reflector assembly in engineering practice.

This paper aims to address a mobile robot localization system that avoids using a dedicated laser scanner, making it possible to reduce implementation costs and the robot’s size. The system has enough precision and robustness to meet the requirements of industrial environments.

Using an algorithm for artificial beacon detection combined with a Kalman Filter and an outlier rejection method, it was possible to enhance the precision and robustness of the overall localization system.

Usually, industrial automatic guide vehicles feature two kinds of lasers: one for navigation placed on top of the robot and another for obstacle detection (security lasers). Recently, security lasers extended their output data with obstacle distance (contours) and reflectivity. These new features made it possible to develop a novel localization system based on a security laser.

Once the proposed methodology is completely validated, in the future, a scheme for global localization and failure detection should be addressed.

This paper presents a comparison between the presented approach and a commercial localization system for industry. The proposed algorithms were tested in an industrial application under realistic working conditions.

The presented methodology represents a gain in the effective cost of the mobile robot platform, as it discards the need for a dedicated laser for localization purposes.

This paper presents a novel approach that benefits from the presence of a security laser on mobile robots (mandatory sensor when considering industrial applications), using it simultaneously with other sensors, not only to guarantee safety conditions during operation but also to locate the robot in the environment. This paper is also valuable because of the comparison made with a commercialized system, as well as the tests conducted in real industrial environments, which prove that the approach presented is suitable for working under these demanding conditions.

The purpose of this paper is to analyze the effect of the space thermal effect on satellite antenna.

In this paper, according to the geometric characteristics of parabolic reflector, the transient temperature field of an element along its thickness direction is built for shell structures using finite element discretization and the quadratic function interpolation, and heat conduction equations are derived based on the theory of the thermo-elastic dynamics. The modeling theory of rigid–flexible coupling system considering thermal effect is extended to the satellite antenna system. Then, the coupling dynamic equations are established including coupling stiffness matrix and thermal loaded undergoing a large overall motion. Finally, an adaptive controller is proposed and the adaptive update laws are designed under the parameter uncertainty.

The results of dynamic characteristic analysis show that the dynamic thermal loaded coupled with structure deformation induce the unstable vibration and coupled flutter. Further, the coupling effect degrades the antenna pointing accuracy seriously and leads to disturbances on satellite base. The results of the simulation show that the adaptive controller can ensure that antenna pointing closes to the expected trajectory progressively, and it demonstrates that the proposed control scheme is feasible and effective.

The paper considers only the effect of space thermal effect to satellite antenna. Further research could be done on the flexible multibody system by considering joint clearance in the future research.

The conclusions of this paper would be an academic significance and engineering value for the analysis and control of satellite antenna pointing.

This study aims to incorporate the Honey and Mumford’s learning styles questionnaire (LSQ) to assess the learning style preferences of postgraduate students at the British University in Dubai (BUiD), as well as investigating whether there are statistically significant differences in such preferences from demographic and academic characteristics perspective.

Questionnaires were distributed to a sample of 200 students (males and females) in various postgraduate programs. Descriptive statistics analysis presented the main characteristics of the respondents and the results of the study. The independent samples t-test and Kurskal–Wallis test determined if there are significant differences in learning style preferences among the postgraduate students because of their demographic and academic characteristics.

The results revealed that postgraduate students preferred the theorist (20.36), reflector (20.31), pragmatist (19.00) and activist (18.62) learning styles, while no significant statistical differences were found across the four learning styles from demographic and academic characteristics standpoint.

On one hand, the present study has several limitations. First, the findings of the study are based on data from only single university. Second, the sample is limited to postgraduate students. Third, the results are based on a self-reported questionnaire, which might affect their reliability. On the other hand, this study has some implications for educators and students. Its results could help educator adopt appropriate teaching styles and strategies that match the preferred learning styles of the majority of their students. Students themselves could also benefit from knowing their own learning style.

The present study is the first scholarly attempt to explore learning style preferences of postgraduate students in the UAE higher education context.

The purpose of this paper is to find an optimized thin-film amorphous silicon solar cell design by numerically optimizing the light trapping efficiency of a pyramid-structured back-reflector using a frequency-domain finite element Maxwell solver. For this purpose short circuit current densities and absorption spectra within the investigated solar cell model are systematically analyzed. Furthermore, the authors employ a topology simulation method to accurately predict the material layer interfaces within the investigated solar cell model. The method simulates the chemical vapor deposition (CVD) process that is typically used to fabricate thin-film solar cells by combining a ballistic transport and reaction model (BTRM) with a level-set method in an iterative approach. Predicted solar cell models are far more realistic compared to solar cell models created assuming conformal material growth. The purpose of the topology simulation method is to increase the accuracy of thin-film solar cell models in order to facilitate highly accurate simulation results in solar cell design optimizations.

The authors perform numeric optimizations using a frequency domain finite element Maxwell solver. Topology simulations are carried out using a BTRM combined with a level-set method in an iterative fashion.

The simulation results reveal that the employed pyramid structured back-reflectors effectively increase the light path in the absorber mainly by exciting photonic waveguide modes. In using the optimization approach, the authors have identified solar cell models with cell periodicities around 480 nm and pyramid base widths around 450 nm to yield the highest short circuit current densities. Compared to equivalent solar cell models with flat back-reflectors, computed short circuit current densities are significantly increased. Furthermore, the paper finds that the solar cell models computed using the topology simulation approach represent a far more realistic approximation to a real solar cell stack compared to solar cell models computed by a conformal material growth assumption.

So far in the topology simulation approach the authors assume CVD as the material deposition process for all material layers. However, during the fabrication process sputtering (i.e. physical vapor deposition) will be employed for the Al:ZnO and ITO layers. In the framework of this ongoing research project the authors will extend the topology simulation approach to take the different material deposition processes into account. The differences in predicted material interfaces will presumably be only minor compared to the results shown here and certainly be insignificant relative to the differences the authors observe for solar cell models computed assuming conformal material growth.

The authors systematically investigate and optimize the light trapping efficiency of a pyramid nano-structured back-reflector using rigorous electromagnetic field computations with a 3D finite element Maxwell solver. To the authors’ knowledge such an investigation has not been carried out yet in the solar cell research literature. The topology simulation approach (to the best of the authors’ knowledge) has previously not been applied to the modelling of solar cells. Typically a conformal layer growth assumption is used instead.

This paper proposes to examine a simple and cost‐effective method of integrating a reflector surface with a silicon‐based microfluidic channel for enhanced biosensing through the method of fluorescence in a microfluidics and nanofluidics‐based lab‐on‐a‐chip device.

Herein, the reflector is integrated with silicon‐based microfluidic channels and fluorescence measurements were carried out using alexafluor 647 particles. Two types of microfluidic channel surfaces were used, with and without reflector integration, for the experiments.

The experimental results prove that the proposed technique of partial reflector integration within microfluidic or nanofluidic channel surfaces is highly suitable for fluorescence‐based detection of single molecules and low concentration fluorophore‐tagged receptors.

It is believed that this is a novel work of integrating a reflector with a microfluidic channel surface for fluorescence‐based biodetection. This method will be very useful for fluorescence‐based biosensors in detecting low concentration fluorophores and single molecules.

This paper scrutinizes exergy loss and hydrothermal analysis of Linear Fresnel Reflector (LFR) unit by means of FLUENT. Several mirrors were used to guide the solar radiation inside the receiver, which has parabolic shape. Radiation model was used to simulate radiation mode.

Heat losses from receiver should be minimized to reach the optimized design. Outputs were summarized as contours of incident radiation, isotherm and streamline. Outputs were classified in terms of contours and plots to depict the influence of temperature of hot wall, wind velocity and configurations on performance of Linear Fresnel Reflector (LFR) based on thermal and exergy treatment. Four arrangements for LFR units are considered and all of them have same height.

Greatest Nu and E_x can be obtained for case D due to the highest heat loss from hot wall. Share of radiative heat flux relative to total heat flux is about 94% for case D. In case D when T_r = 0.388, As h_ext rises from 5 to 20, Nu_total enhances about 11.42% when T_r = 0.388. By selecting case D instead of case A, E_x rises about 16.14% for lowest T_r. Nu_total and E_x of case D augment by 3.65 and 6.23 times with rise of T_r when h_ext = 5. To evaluate the thermal performance (η_th) of system, absorber pipe was inserted below the parabolic reflector and 12 mirrors were used above the ground. The outputs revealed that η_th decreases about 14.31% and 2.54% with augment of T_in and Q if other factors are minimum.

This paper scrutinizes exergy loss and hydrothermal analysis of LFR unit by means of finite volume method. Several mirror used to guide the solar radiation inside the receiver, which has parabolic shape. DO model was used to simulate radiation mode. Heat losses from receiver should be minimized to reach the optimized design. Outputs were summarized as contours of incident radiation, isotherm and streamline.

Peter Honey and Alan Mumford published in December 1982 The Manual of Learning Styles which brought to a wider audience the advantages of a determination of the different preferences of people for the way they learn. The approach suggested by Honey and Mumford was not completely new, but offered an alternative approach to the other major learning style inventory, that by Kolb. A number of people had been unhappy with the construction and results of Kolb's Learning Style Inventory and it had been positively attacked from an academic viewpoint by Freedman and Stumpf.

The purpose of this paper is to address the use of Honey and Mumford’s Learning Styles Questionnaire (LSQ) to investigate the learning style preferences of undergraduate students at the American University of Ras Al Khaimah (AURAK) in the United Arab Emirates (UAE) culture. It also investigates whether there are significant differences across the four dimensions of learning styles due to students’ demographics.

Questionnaires were distributed to a sample of 200 undergraduate students at AURAK in the UAE. The majority of students were Arabic native-speakers. Descriptive statistics were used to present the main characteristics of respondents and the results of the study. The independent samples t-test, Mann–Whitney test and Kurskal–Wallis test were used to find out if there are significant differences across the four dimensions of learning styles due to students’ demographics.

The results of the study illustrated that undergraduate students at AURAK have preferences for the reflector (15.0), pragmatist (14.2), theorist (13.9) and activist (12.3) learning styles. Moreover, there are only significant differences between Emirati and non-Emirati students across the four learning styles and between single and married students in the theorist learning style.

This study has a number of limitations. First, the findings of the study are based on the data collected from only one university. Second, the sample is limited to undergraduate students and, therefore, it excludes graduate students who might have different experiences. Third, the results are based on a self-reported questionnaire which might affect the reliability of the results. On the other hand, it has a number of implications for educators and students. Educators will benefit from the results of this study in the sense that they need to adopt teaching styles and strategies that match the learning styles of the majority of their students. Students themselves will benefit from knowing their own learning style.

The present study validates a learning style theory developed in a western culture in an Arabic culture.