Survey of Robotics in Education,Taxonomy, Applications,and Platforms during COVID-19

The coronavirus disease 2019 (COVID-19) is characterized as a disease caused by a novel coronavirus known as severe acute respiratory coronavirus syndrome 2 (SARS-CoV-2; formerly known as 2019-nCoV). In December 2019, COVID-19 began to appear in a few countries. By the beginning of 2020, it had spread to most countries across the world. This is when education challenges began to arise. The COVID-19 crisis led to the closure of thousands of schools and universities all over the world. Such a situation requires reliance on e-learning and robotics education for students to continue their studies to avoid the mingling between people and students. In relation to this alternative learning solution, the present study was conducted. A systematic literature review on educational robotics (ER) keywords between 2015–2020 was carried out for the purpose to review a total of 2253 articles from the selected sources; Scopus (452), Taylor & Francis (311), Science Direct (427), IEEE Xplore (221), and Web of Science (842). This review procedure was labelled as Taxonomy 1. After filtering Taxonomy 1, it was found that 98 scientific articles formed the so-called Taxonomy II that was categorized into six categories: (i) Robotics concepts, (ii) Device, (iii) Robotic applications, (iv) Manufacturing robots, (v) Robotics analysis, and (vi) Education/taxonomy. For this study, only 35 articles in this specific field were selected, of which were then assigned into three categories: (i) Application, (ii) Platform, and (iii) Educational. The results show that the application category carries 17.4%, platform 20%, and education 22.85%. This study serves as the application platform to help students, academics, and researchers.     

Formal analysis of seamless application execution in mobile cloud computing

Mobile cloud computing augments the resource-constrained mobile devices to run rich mobile applications by leveraging the cloud resources and services. Compute-intensive mobile apps require significant communication resources for migrating the code from mobile devices to the cloud. For such apps, distributed application execution frameworks (DAEF) have been proposed in the literature. These frameworks either migrate the mobile app code during runtime or keep the app synchronized with another remotely executed app on the cloud. Frameworks also support mobile app live migration to cater for compute node mobility. One key research question arises is how successful are these DAEFs in achieving the seamless application execution under various network conditions? The answer to this question entails formal analysis of the DAEFs to determine the realistic bounds on propagation delay, bandwidth and application interaction with mobile device for various types and sizes of apps. In this research, we apply formal analysis techniques to define the execution time of the app and the time required for code migration. We also define three conditions for seamless application execution. Given realistic values for processor speed, application executable size, possible number of executed instructions, network propagation delay and transmission delay, we show what components of the mobile app need to be migrated during execution to the cloud. Finally, we compute realistic bounds for the app size (that can be executed seamlessly) based on important features which include cloud and device resources, bandwidth and latency profile.     

Synthesis and characterization of side‐chain liquid‐crystalline polyacrylates containing azobenzene moieties

Syntheses of novel liquid‐crystalline polymers containing azobenzene moieties were performed by a convenient route with an acrylate backbone. The azobenzenes were key intermediates of the monomers, and side‐chain liquid‐crystalline polymers were prepared, that is, poly[α‐{4‐[(4‐acetylphenyl)azo]phenoxy}alkyloxy]acrylates, for which the spacer length was 3 or 11 methylene units. In addition, poly[3‐{4‐[(3,5‐dimethylphenyl)azo]phenoxy}propyloxy]acrylate was prepared with a spacer length of 3 methylene units. The structures of the precursors, monomers, and polymers were characterized with Fourier transform infrared, ¹H‐NMR, and ¹³C‐NMR techniques. The polymers were obtained by conventional free‐radical polymerization with 2,2′‐azobisisobutyronitrile as an initiator. The phase‐transition temperatures of the polymers were studied with differential scanning calorimetry, and the phase structures were evaluated with a polarizing optical microscopy technique. The results showed that two of the monomers and their corresponding polymers exhibited nematic liquid‐crystalline behavior, and one of the monomers and its corresponding polymer showed smectic liquid‐crystalline behavior. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2653–2661, 2002     

Potential of tipping flush gate for sedimentation management in open stormwater sewer

This paper presents the design of a tipping flush gate and its potential use in servicing open storm sewers in terms of sedimentation management. The tipping flush gate was installed in a section of open concrete storm sewer located in a commercial area in Taman Pekaka, Nibong Tebal, Penang, Malaysia. Monitoring of the gate operation and performance was done from 14^th November 2012 to 15^th March 2013 covering the beginning and end of the wet season. The sediment profile inside the sewer was measured after each operation of the gate or rainfall event. Results showed that the gate was effective in reducing naturally accumulated sediment in the chosen sewer section. However, proper litter management is needed if the gate is to be implemented in open storm sewer systems. A design guideline for the usage of a tipping flush gate for open storm sewers is also presented in this paper.     

Artifact removal in magnetoencephalogram background activity with independent component analysis

The aim of this study was to assess whether independent component analysis (ICA) could be valuable to remove power line noise, cardiac, and ocular artifacts from magnetoencephalogram (MEG) background activity. The MEGs were recorded from 11 subjects with a 148-channel whole-head magnetometer. We used a statistical criterion to estimate the number of independent components. Then, a robust ICA algorithm decomposed the MEG epochs and several methods were applied to detect those artifacts. The whole process had been previously tested on synthetic data. We found that the line noise components could be easily detected by their frequency spectrum. In addition, the ocular artifacts could be identified by their frequency characteristics and scalp topography. Moreover, the cardiac artifact was better recognized by its skewness value than by its kurtosis one. Finally, the MEG signals were compared before and after artifact rejection to evaluate our method.     

Dual-photoelastic-modulator-based polarimetric imaging concept for aerosol remote sensing

A dual-photoelastic-modulator- (PEM-) based spectropolarimetric camera concept is presented as an approach for global aerosol monitoring from space. The most challenging performance objective is to measure degree of linear polarization (DOLP) with an uncertainty of less than 0.5% in multiple spectral bands, at moderately high spatial resolution, over a wide field of view, and for the duration of a multiyear mission. To achieve this, the tandem PEMs are operated as an electro-optic circular retardance modulator within a high-performance reflective imaging system. Operating the PEMs at slightly different resonant frequencies generates a beat signal that modulates the polarized component of the incident light at a much lower heterodyne frequency. The Stokes parameter ratio q = Q/I is obtained from measurements acquired from each pixel during a single frame, providing insensitivity to pixel responsivity drift and minimizing polarization artifacts that conventionally arise when this quantity is derived from differences in the signals from separate detectors. Similarly, u = U/I is obtained from a different pixel; q and u are then combined to form the DOLP. A detailed accuracy and tolerance analysis for this polarimeter is presented.     

Case Study: Flood Mitigation of the Muda River, Malaysia

The 2003 flood of the Muda River reached 1,340?m3/s at Ladang Victoria and adversely impacted 45,000 people in Malaysia. A flood control remediation plan proposed a levee height based on a 50-year discharge of 1,815?m3/s obtained from hydrologic models. This design discharge falls outside the 95% confidence intervals of the flood frequency analysis based on field measurements. Instream sand and gravel mining operations also caused excessive riverbed degradation, which largely off sets apparent benefits for flood control. Pumping stations have been systematically required at irrigation canal intakes. Several bridge piers have also been severely undermined and emergency abutment protection works were needed in several places. Instream sand and gravel mining activities should be replaced with offstream mining in the future.     

Review and comparison study of hybrid diesel/solar/hydro/fuel cell energy schemes for a rural ICT Telecenter

In this paper, the rural electrification study of an ICT Telecenter in particular reference to the Kelabit Highland of Sarawak is presented. The use of diesel generator and its associated environmental implications is first discussed. The cost-effectiveness of the present solar PV system and the solar/hydro schemes for rural electrification of the rural ICT are evaluated employing the HOMER simulation software, considering sustainability factors such as system efficiency, weather, fuel costs, operating and maintaining costs. Subsequently, simple novel Hybrid Energy Performance Equations and the associated Energy Performance Curves are derived and introduced, respectively, which provide a visualization model, simplifying hybrid system analysis. Results obtained in this study have shown that combined power schemes is more sustainable in terms of supplying electricity to the Telecenter compared to a stand-alone PV system due to prolong cloudy and dense haze periods. The hybrid systems can have efficiency range of ∼15%–75% compared to PV stand-alone of only ∼10%, indicating hybrid systems are more reliable and sustainable – in minimizing both energy losses and excess energy.