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1 – 10 of 174T. Tobita, K. Niki, T. Makita, H. Takasago and H. Miki
To obtain the best moisture‐proof and most reliable protective coating for an amorphous silicon image sensor (A4 documents), three methods of coating and patterning…
Abstract
To obtain the best moisture‐proof and most reliable protective coating for an amorphous silicon image sensor (A4 documents), three methods of coating and patterning processes and 15 types of resin classified into five kinds of materials were evaluated. Through this study, a screen‐printing method using silicone resin material cured under conditions of 150°C for 60 minutes to form a 60 µm thick protective coating film was selected because of the simplicity of its fabrication process compared with the other two methods. The a‐Si photodiodes were tested under conditions of 121°C‐2 atm. for 300 hours, −30°C to 100°C for 350 cycles and 85°C for 500 hours, and their characteristics were not negatively affected.
To consider aspects of a theory of systemic construction by discussing two concepts which will assist in our understanding of the surrounding world which it is considered…
Abstract
Purpose
To consider aspects of a theory of systemic construction by discussing two concepts which will assist in our understanding of the surrounding world which it is considered is made of both systemic and non‐systemic entities.
Design/methodology/approach
Considers how these entities (metasystem, network, transitron etc.) can be conceived and defined. Systemic frames notions are presented and examples of systems given. Discusses the historic use of the word “system” and systemic thinking and its varieties.
Findings
Discovered that on the basis of these concepts, an understanding of the surrounding world can be achieved which is not homogeneous but made of both systemic and non‐systemic entities. These can change when certain systemic properties are reached as well as in their specific degrees in their limitations and paradoxes.
Originality/value
Introduces an original approach to the life support system by proposing concepts that are discussed and defined and that will provide cyberneticians and systemists with a revised view of systemic thinking.
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Feng Dong, Hao Chen, Shuai Xu and Sihang Cui
This paper aims to present a novel position sensorless control scheme with fault-tolerance ability for switched reluctance motor at low speed.
Abstract
Purpose
This paper aims to present a novel position sensorless control scheme with fault-tolerance ability for switched reluctance motor at low speed.
Design/methodology/approach
First, the detection pulses are injected in the freewheeling and idle intervals of each phase. Second, the aligned position of each phase can be detected by comparing the consecutive rise time of detection current. Third, the whole-region rotor position and real-time rotational speed can be updated four times for the improvement of detection accuracy. Finally, the fault-tolerant control strategy is performed to enhance the robustness and reliability of proposed sensorless scheme under faulty conditions.
Findings
Based on proposed sensorless control strategy, the estimated rotor position is in good agreement with the actual rotor position and the maximum rotor position error is 1.5°. Meanwhile, the proposed sensorless scheme is still effective when the motor with multiphase loss and the maximum rotor position error is 1.9°. Moreover, the accuracy of the rotor position estimation can be ensured even if the motor is in an accelerated state or decelerated state.
Originality/value
The proposed sensorless method does not require extensive memory, complicated computation and prior knowledge of the electromagnetic properties of the motor, which is easy to implement. Furthermore, it is suitable for different control strategies at low speed without negative torque generation.
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Anton Saveliev, Egor Aksamentov and Evgenii Karasev
The purpose of this paper is to analyze the development of a novel approach for automated terrain mapping a robotic vehicles path tracing.
Abstract
Purpose
The purpose of this paper is to analyze the development of a novel approach for automated terrain mapping a robotic vehicles path tracing.
Design/methodology/approach
The approach includes stitching of images, obtained from unmanned aerial vehicle, based on ORB descriptors, into an orthomosaic image and the GPS-coordinates are binded to the corresponding pixels of the map. The obtained image is fed to a neural network MASK R-CNN for detection and classification regions, which are potentially dangerous for robotic vehicles motion. To visualize the obtained map and obstacles on it, the authors propose their own application architecture. Users can any time edit the present areas or add new ones, which are not intended for robotic vehicles traffic. Then the GPS-coordinates of these areas are passed to robotic vehicles and the optimal route is traced based on this data
Findings
The developed approach allows revealing impassable regions on terrain map and associating them with GPS-coordinates, whereas these regions can be edited by the user.
Practical implications
The total duration of the algorithm, including the step with Mask R-CNN network on the same dataset of 120 items was 7.5 s.
Originality/value
Creating an orthophotomap from 120 images with image resolution of 470 × 425 px requires less than 6 s on a laptop with moderate computing power, what justifies using such algorithms in the field without any powerful and expensive hardware.
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Hardik A. Shah, Satish K. Shah and Rakesh M. Patel
This paper presents real time hardware implementation of DSP based 180 degree control algorithm and MATLAB SIMULINK based software Implementation for 3-phase 4-leg IGBT…
Abstract
This paper presents real time hardware implementation of DSP based 180 degree control algorithm and MATLAB SIMULINK based software Implementation for 3-phase 4-leg IGBT based voltage source inverter. Triggering pulses generated using Texas Instruments TMS 320F28335 DSP controller and that triggers the 6 IGBTs of Voltage source inverter. Results of pulse generated using DSP and output of the Voltage source inverter were captured using Digital Storage Oscilloscope. FFT analysis for output signal of software and hardware implementation presented with the analysis.
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Shabnam Karimi, Fatemeh Mahzoon, Sirus Javadpour and Kamal Janghorban
This paper aims to study the deposition of ZrO2 on 316L stainless steel surface using cathodic plasma electrolytic deposition (CPED) technique in potassium…
Abstract
Purpose
This paper aims to study the deposition of ZrO2 on 316L stainless steel surface using cathodic plasma electrolytic deposition (CPED) technique in potassium hexafluorozirconate (K2ZrF6) electrolyte solution to promote its corrosion and tribological properties.
Design/methodology/approach
Plasma electrolytic oxidizing (PEO) technique is commonly used to form zirconium dioxide (ZrO2) on various substrates. But, in this paper, cathodic type of this technique (CPED) was used.
Findings
Composition of the surface layer was analyzed by X-ray diffraction (XRD) and the formation of ZrO2 on the substrate was confirmed. Scanning electron microscope (SEM) was used to observe the unique morphology of the surface layer. The corrosion resistance of the coated surface was investigated by electrochemical methods involving cyclic voltammetery in Ringer’s solution. The treated sample showed a better pitting resistance. Pin-on-disk wear tests revealed that the friction coefficient of the coated sample is lower than that of the substrate. Also, it was shown that hardness and roughness of the coated sample increased after plasma electrolytic treatment.
Originality/value
This paper considers the CPED of ZrO2 coating on 316L stainless steel. Some recent research works with ZrO2 coating have been prepared by PEO. There is limited or no record on the study of ZrO2 coatings by CPED process. In this study, the effort has been made to prepare a zirconia (ZrO2) coating on the stainless steel substrate through cathodic plasma electrolytic process under 200 V. Due to the excellent wear resistance, ZrO2 may be used as a high resistant and protective coating on stainless steels, which are widely used in industries and biomedical applications.
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A. Kaveh and M. Shahrouzi
The generality of the genetic search in the light of proper coding schemes, together with its non‐gradient‐based search, has made it popular for many discrete problems…
Abstract
Purpose
The generality of the genetic search in the light of proper coding schemes, together with its non‐gradient‐based search, has made it popular for many discrete problems including structural optimization. However, the required computational effort increases as the cardinality of the search space and the number of design variables increase. Memetic algorithms are formal attempts to reduce such a drawback for real‐world problems incorporating some kind of problem‐specific information. This paper aims to address this issue.
Design/methodology/approach
In this paper both Lamarckian and Baldwinian approaches for meme evolution are implemented using the power of graph theory in topology assessment. For this purpose, the concept of load path connectivity in frame bracing layouts is introduced and utilized by the proposed graph theoretical algorithms. As an additional search refinement tool, a dynamic mutation band control is recommended. In each case, the results are studied via a set of ultimate design family rather than one pseudo optimum. The method is further tested using a number of steel frame examples and its efficiency is compared with conventional genetic search.
Findings
Here, the problem of bracing layout optimization in steel frames is studied utilizing a number of topological guidelines.
Originality/value
The method of this paper attempts to reduce the computational effort for optimal design of real‐world problems incorporating some kind of problem‐specific information.
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Mozhgan Hosseinnezhad and Hanieh Shaki
The purpose of this paper is to study the substituent effect in dye-sensitized solar cells’ (DSSCs) performance. For this end, three new metal organic dyes with DPA…
Abstract
Purpose
The purpose of this paper is to study the substituent effect in dye-sensitized solar cells’ (DSSCs) performance. For this end, three new metal organic dyes with DPA structure were synthesized. For investigation of the substituent effect, two different anchoring groups, namely, 1,3-dioxo-1Hbenz[de]isoquinolin-2(3H)-yl)benzenesulfonamides and 1,8-naphthalimide, were used.
Design/methodology/approach
Three organic dyes based on azo were selected, which contain various electron donor groups. Absorption properties of purified dyes were studied in solution and on photoelectrode (TiO2 and ZnO) substrate. DSSCs were prepared to determine the photovoltaic performance of each photosensitizer.
Findings
The results showed that all organic dyes form J-aggregation on the photoanode substrate. Cyclic voltammetry results for all organic dyes ensured an energetically permissible and thermodynamically favorable charge transfer throughout the continuous cycle of photo-electric conversion. The results illustrate conversion efficiencies of cells based on solution Dyes 1, 2 and 3 and TiO2 as 3.44, 4.71 and 4.82 per cent, respectively. The conversion efficiencies of cells based on solution Dye 1, 2 and 3 and ZnO are 3.21, 4.09 and 4.14 per cent, respectively.
Practical implications
In this study, the development of effect of assembling materials, offering improved photovoltaic properties.
Social implications
Organic dye attracts more and more attention because of its low-cost, facile route synthesis and less-hazardous properties.
Originality/value
To the best of the authors’ knowledge, the effect of anchoring agent and nanostructure on DSSCs performance was investigated for the first time.
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Chanan Syan and Yousef Mostefai
The automated manufacturing systems of the future can only befeasible if they have capabilities to recover automatically from faultsand errors effectively and efficiently…
Abstract
The automated manufacturing systems of the future can only be feasible if they have capabilities to recover automatically from faults and errors effectively and efficiently. Reports on the work carried out looking at error recovery problems in manufacturing cell controllers. Cell control systems also invariably manage and schedule work in an automated cell as well as carrying out the general tasks of communications, sequencing and recording. Presents a model for error recovery capability which uses system information, data and prior knowledge of errors to recover from system errors. Elucidates the structure and operation of the cell controller developed. Work so far has shown promise in achieving automatic recovery capability in cell control systems. Finally identifies further developments for future work.
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Prashant Sahni, Poonam Aggarwal, Savita Sharma and Baljit Singh
The purpose of this paper is to acquaint the readers with the insights regarding the interventions of microalgal technology for production of metabolites and functional…
Abstract
Purpose
The purpose of this paper is to acquaint the readers with the insights regarding the interventions of microalgal technology for production of metabolites and functional ingredients from microalgae for food and nutraceutical application and exploration of microalgae biomass for food application.
Design/methodology/approach
Various information databases such as journals, library catalogues and professional websites were used to collect information pertaining to application of microalgae in food and nutraceutical sector. Systematic review was made with recent studies covering the vital aspects of art of microalgae cultivation for metabolite production, functional ingredients from microalgae, market scenario and utilisation of microalgae biomass for the valorisation of the food products. Key points have been discussed after every section to highlight the practical implications to make this review more insightful for the readers.
Findings
Microalgal technology provides sustainable solution for its application in food and nutraceutical sector. The heart of metabolite production lies in the optimisation of cultivation conditions of microalgae. Wide array of functional components are obtained from microalgae. Microalgae offer an alternative source for omega-3 fatty acids. Microalgae is widely exploited for production of pigments, namely, ß-carotene, astaxanthin, lutein, phycocyanin and chlorophyll, that have important implication as natural colourants and nutraceuticals in food. Larger diversity of sterols found in microalgae confers bioactivity. Microalgae is finding its place in market shelves as nutraceuticals where its functional ingredients are in the form of powder, tablets, extract and beverages and in innovative products such as microalgae protein and fat, culinary algae oil and butter. Sprulina and Chlorella are popular choice for the supplementation of food products with microalgae biomass.
Originality/value
This is a comprehensive review that highlights the application of microalgal technology for the development of healthy food products and presents holistic intervention in food and nutraceutical sector.
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