bluuebunny/crossref_metadata_2025_split huggingface dataset:
Noether’s theorem, the Rund–Trautman function, and adiabatic invariance
Authors: Gourieux Thierry , Leone Raphaël 
Published: March 2021

Abstract
This article focuses on the recognition of an important quantity that will be called the Rund–Trautman function. It already plays a central role in Noether’s theorem since its vanishing characterizes a symmetry and leads to a conservation law. The main aim of the paper will be to show how, in the realm of classical mechanics, an ‘almost’ vanishing Rund–Trautman function accompanying an ‘almost’ symmetry leads to an ‘almost’ constant of motion, especially within the adiabatic hypothesis for which the ‘almostness’ in question is in some sense measured by the slowness of time-dependent parameters. To this end, the Rund–Trautman function is first introduced and analyzed in detail, then it is implemented for the general one-dimensional problem. Finally, its relevance in the adiabatic context is examined through the example of the harmonic oscillator with a slowly varying frequency. Notably, for some frequency profiles, explicit expansions of adiabatic invariants are derived through it and an illustrative numerical test is realized.
Strain-dependent optical properties of the novel monolayer group-IV dichalcogenides SiS2 semiconductor: a first-principles study
Authors: Chen Qing-Yuan , Liu Ming-Yang , Cao Chao , He Yao 
Published: March 2021

Abstract
We studied the structural, electronic, and optical characters of SiS2, a new type of group IV–VI two-dimensional semiconductor, in this article. We focused on monolayer SiS2 and its characteristic changes when different strains are applied on it. Results reveal that the monolayer SiS2 is dynamically stable when no strain is applied. In terms of electronic properties, it remains a semiconductor under applied strain within the range from −10% to 10%. Besides, its indirect band-gap is altered regularly after applying a strain, whereas different strains lead to various changing trends. As for its optical properties, it exhibits remarkable transparency for infrared and most visible light. Its main absorption and reflection regions lie in the blue and ultraviolet areas. The applied uniaxial strain causes its different optical properties along the armchair direction and zigzag direction. Moreover, the tensile strain could tune its optical properties more effectively than the compressive strain. When different strains are applied, the major changes are in blue and ultraviolet regions, but only minor changes can be found in infrared and visible regions. So its optical properties reveal good stability in infrared and visible regions. Therefore, SiS2 has a promising prospect in nano-electronic and nano-photoelectric devices.
Hysteresis loss calculations of 2D and 3D large-scale HTS coil models: from multi-scale method to multi-dimension method
Authors: Wang Lei , Chen Yan 
Published: March 2021

Abstract
Here we propose a new approach capable of calculating the hysteresis loss of 3D HTS coil models based on the modeling framework of the multi-scale method. The study enhances the multi-scale method for 2D simulations by introducing the homogenization technique to simplify the topological features of coils’ cross sections. With the simplification, a 3D A-formulation magnetostatic model is built for magnetic field estimation, while a 2D H-formulation superconducting model is solved for the tape’s current density and hysteresis loss. Since different spatial dimensions are employed in the submodels, we refer to it as the multi-dimension method. We demonstrate the data transferring between the 2D or 3D homogenized coil submodel and the 2D single-tape submodel. The benchmark results show that hysteresis losses from the developed models and reference models are in good agreement, with errors of less than 1% and 6% in simulating the target 2D solenoid coil and 3D racetrack coil, respectively. The distributions of current density and magnetic field in both models are highly consistent. Meanwhile, the developed models speed up the calculations by one to five times compared with the reference models. Due to the easy calculation of 3D magnetostatic models and 2D superconducting models, the multi-dimension method may pave a new way to 3D electromagnetic simulations for larger-scale and more complex high temperature superconducting conductors and coils.
Local affection of weak gravitational field from supercondensates
Authors: Gallerati Antonio 
Published: March 2021

Abstract
We study the mutual interaction between a superconducting sample and the weak, static Earth’s gravitational field, exploiting the gravito-Maxwell formalism combined with the time-dependent Ginzburg-Landau model. We will also determine the appropriate conditions to enhance the desired gravity/superfluid interplay, analysing the effects of thermal fluctuations and optimizing the superconductor parameters and sample geometry.
Investigation on the Effect of the Feature Extraction Backbone for Small Object Segmentation using Fully Convolutional Neural Network in Traffic Signs Application
Authors: Elhawary H M , Shapiaib M I , Elfakharany A 
Published: March 2021

Abstract
Small objects are widely found in different applications such as traffic signs and to segment those objects make it difficult to extract features due to the small number of pixels. Previous research has been done to show how error prone the semantic segmentation networks to small objects in variance of application such as medical images and remote sensing and how it leads to class imbalance. However, small object segmentation seems to be tricky and making the network struggle. Recently there are small amount of research has been done in the effect of the feature extraction backbone to the small object datasets. In this paper we investigate the effect of different backbone feature extraction such as AlexNet, VGGNet, GoogleNet on an imbalanced small objects dataset after grouping them by shape and colour in the Fully Convolutional Networks (FCN). We measure the performance on PASCAL VOC and Malaysian Traffic Sign Dataset (MTSD) showing the pixel accuracy, mean accuracy per class, mean IoU and frequency weighted IoU for each backbone and FCN. The results show that VGGNet as a backbone with Cross Entropy (CE) combined with Dice Loss (DL) achieves the highest score in mean IoU for imbalanced dataset but not for balanced dataset. However, in the imbalanced dataset major classes have a higher probability to confuse with minor classes due to the class imbalance. In conclusion we investigate different backbone networks with grouped labels dataset in shape and colour and we recommend using VGGNet FCN with CE combined with DL for imbalanced datasets.
A Systematic Review on Internet of Things in Language Practice
Authors: Kew S N , Koh T W , Tasir Z , Jumaat N F , Abd Halim N D 
Published: March 2021

Abstract
Language is a necessary component in our life as we need it to communicate with each other. It is important to provide more alternatives and resources to the language learners to effectively learn and master the language well. In fact, the growth of technology has made impact on the educational aspects over the years. Particularly, researchers are exploring the potential for the Internet of Things to help learners in language learning. Even though different learning and teaching applications on various types of learning devices have been developed to enhance language learning and teaching practices; nonetheless, the systematic review studies on the Internet of Things in language practice are still limited. Therefore, this paper aims to fill in this research gap by presenting a systematic review of the Internet of Things in language practice with the purpose to provide an overview of how Internet of Things has been utilised in language learning in the educational institution. By searching the key words via numerous electronic databases, a total of 288 papers was found. After eliminating articles that did not fulfil the requirements, only 17 articles were chosen and analysed in this paper. This paper analysed these selected articles for the types of languages being focused on, the types of technology used in language learning, its purpose, effects and examples. Based on the analysis of the results, most of the studies have designed new technology tools that are used to enhance learners’ language competency, including children, primary school students and university students. The findings also found these technology tools focus on different types of languages. Among these languages, English language is the most popular language that researches have studied. Moreover, most of the studies also reported that learners’ language competency was improved due to the implementation of Internet of Things. Lastly, it is suggested that more relevant future research should be conducted.
Structure Base Virtual Screening for Identifying Inflammatory Inhibitors
Authors: Tap Fatahiya Mohamed , Ahmad Khairudin Nurul Bahiyah , Mustafa Iswaibah 
Published: March 2021

Abstract
Phospholipase A2 (PLA2) is an enzyme that induces inflammation, making PLA2 activity an effective approach to reduce inflammation. Therefore, investigating natural compounds for this PLA2 inhibitory activity has important therapeutic potential. The objective of this study was to investigate the potential inhibitors for inflammatory diseases through a virtual screening approach. Out of 10,000 compounds from zinc database, only five compounds were selected based on the lowest free energy binding and further used for molecular interaction analysis. These five compounds were Metacetamol (-11.43 kcal/mol), 7-Methoxybenzofuran-2-carboxylic acid (-10.22 kcal/mol), 6-nitro-4H-1,3-benzodioxine-8-carbaldehyde (-10.08kcal/mol), 4-(2-Amino-1,3-thiazol-4-yl)benzene-1,3-diol (-9.86 kcal/mol), and 1-Ethyl-1H-indole-3-carbaldehyde (-9.53 kcal/mol). These findings also provide insight on valuable implications for the use of these five compounds in treating inflammation, and may help researchers develop more natural bioactive compounds in daily foods as anti-inflammatory agent.
Resilience Building among University Students: A Heart Rate Variability Biofeedback Study
Authors: Shahirah Sha’ari N A , Amin M K M 
Published: March 2021

Abstract
National Health and Morbidity Survey 2017 stated that 1 in 5 adolescents in Malaysia are having depression while 2 in 5 are anxious and 1 in 10 adolescents are in a stress state. This statistic is worrying as adolescents will be the future leaders of our country. Due to this increasing mental health problems, heart rate variability biofeedback technologies are used to increase resilience among university students. A person who is low in resilience is easily gets stress and a higher tendency to be depressed. Based on previous research, there were many kinds of research that have been done to quantify resilience through psychometric tools for example questionnaires and surveys. However, to the best of our knowledge, there has been little research before this in investigating how efficient heart rate variability biofeedback (HRVB) in improving resilience, especially among university students. The waveform of the HRV able to reflect either the person has low or high resilience. This study is a multidisciplinary field that includes electronics, psychology, and cognitive neuroscience. The aim is to determine the impact of HRV in resilience building among university students through biofeedback training. 120 students from Malaysia-Japan International Institute of Technology (MJIIT) are selected to participate in responding to the Brief Resilience Scale (BRS). BRS is used as psychometric tools to measure the level of resilience of the students. Based on the BRS score, the subjects were divided into 3 categories of resilience which are low resilience, normal resilience, and high resilience. The research used EmWave device and software of the HeartMath Institute to collect the variations of the heart rate data. Those who have low resilience took part in the biofeedback training for 5 sessions. The intervention used in the study is the slow breathing technique (6 breaths per min). Based on the HRV power spectrum, HRV data can be divided into 3 parts which are very low frequency (VLF), low frequency (LF) and high frequency (HF). The result obtained after completed all biofeedback training sessions shows that the use of heart rate variability biofeedback helped to increase the level of resilience of the students.
Sodium Chloride Concentration Measurement via Optical Fiber Tip Sensor
Authors: Ja’afar P N S S , Razali N M , Ambran S , Ahmad F 
Published: March 2021

Abstract
Sodium chloride (NaCl) is an essential compound that human needs mainly to regulate the amount of water in body. However, the level intake of NaCl daily consumption should wisely be regulated. Previously, various techniques have been employed to measure NaCl concentrations but high cost and complex fabrication become one of the limitations that need to be overcome. Thus, this paper demonstrates a sodium chloride (NaCl) concentration measurement using an optical fiber tip sensor. The flat end facet of single – mode fiber was used to emit the broadband light at near infrared wavelength region to detect NaCl at different concentration ranging from 0% – 4%. The optical power reading was recorded at every increment of 0.5% of NaCl concentration. When the aqueous NaCl was dropped onto the sensing region, the optical power decreases as the NaCl concentration increases. This experiment has shown that the sensitivity achieved by this sensor was 0.1239 dBm/% with regression value up to 0.999.
Dual-band substrate integrate waveguide slot antenna for 5G applications
Authors: Hamid N , Omran A H 
Published: March 2021

Abstract
The current fifth generation (5G) and millimeterwave technologies are urgently needed to provide huge bandwidth, dual-bands, multi bands, high gain and high directivity radiation pattern beams antennas. However, antennas at millimeterwave suffer from radiation loss and component loss with narrow bandwidth, especially when it is implemented using microstrip structures. Different transmission lines such as waveguide and substrate integrated waveguide (SIW) are studied and introduced for realizing antennas at millimeterwave bands. SIW structures are good candidate for implementation of antenna due to its property of low loss transmission line comprises the properties of microstrip and waveguide technology. However, SIW antennas and structures at millimeterwave have unwanted radiation losses comes from the vias holes. In addition, the vias separation distance is depended on waveguide size, which leads to a bigger size for massive antenna array network at proposed 26 GHz and 28 GHz. Hence, this paper proposed a dual band, compact size, and optimal SIW antenna structure to reduce the vias losses and provides higher bandwidth and gain at 26 GHz and 28 GHz. The proposed design is implemented using three slots to achieve the dual band property and increases the return loss. The proposed design is simulated and studied using CST software. The outcomes of dual-band response at 26 GHz and 28 GHz with a return loss more than 10 dB and a fractional bandwidth of 15% are achieved. A good gain around 8 dB is achieved. These results give a promising solution for realizing a full antenna array based on SIW technology at millimeterwave and 5G technology.
Compact wide band antenna for millimetric communications
Authors: Elsayed Mohamed S. , AboSree Mohamed F. , AbdElazem Mohamed H. 
Published: March 2021

Abstract
A single-layer ultra-wideband microstrip patch antenna loaded with an asymmetrical U-shaped slot for millimetre wave application is presented in this paper. The antenna is coaxial fed, and it is implemented on a Roger 5880 substrate with a relative dielectric constant of 2.2, thickness 3.15 mm, and loss tangent 0.0009. It operates over the frequency in the Ka-band from 31 to 37 GHz in the microwave spectrum. The results of the simulated reflection coefficient, radiation pattern, and maximum gain of the antenna are in fair agreement with the measured ones. Moreover, the measured reflection coefficient is carried out in the labs. The gain of The peak value of 7.4 dB is obtained at 34 GHz.
Recent Trends of the In-Pipe Inspection Robotic System from Academia and Industry Perspectives
Authors: Rashid M Z A , Yakub F , Salim S A S , Roslan S A , Shah H N M , Yeshmukhametov A , Yamamoto Y 
Published: March 2021

Abstract
This paper presents the recent designs of the in-pipe inspection robotic system from the researchers in the academia and industrial fields. The scope of the paper will focus on the designs, locomotion of the systems and the actuator that will actuate or provide force to drive the in-pipe robot forward. The study covers the trends of the research from recent years to date. It is observable that most of the researches conducted by academic researchers focused on the designs and locomotion of the robots which commonly used wheel drive, screw drive and modular locomotion method. The screw drive in-pipe robotic system has a set of wheels located at certain distance apart from the centre of the body with a certain angle so that the system rotates like a screw when it is actuated. On the contrary, the in-pipe robotic system from the industry like oil and gas industry uses wheel type robot combined with other parts like disc, cups, scraper and attached with the sensory system to conduct the inspection.
Post-buckling of bamboo reinforced composite plates
Authors: Mat Kasim F A , Roslan S A H , Rasid Z A , Yakub F , Hassan M Z , Yahaya H 
Published: March 2021

Abstract
Composite materials are preferred as today’s material for aerospace structural applications largely because composites provide high specific strength and stiffness. To their advantages, natural fibers such as bamboo, kenaf, jute and flax have been researched significantly for having high effective strength and stiffness and environmental friendly advantages in being renewable, biodegradable and sustainable. While many structures used in aerospace applications are thin and as such susceptible to buckling problem, this paper presents the study on the buckling and post-buckling of bamboo reinforced composite plates (BRCPs), applying the finite element method software of ANSYS APDL. A compressive load was given to the BFRC and linear buckling analysis was conducted first. The determined critical load from this analysis was then used in the non-linear post-buckling analysis to give the post-buckling path of the BRFC. In both linear and non-linear analysis, the effect of BRFC thickness was considered while both angle-ply and cross-ply orientations were used. The results of deflection of a composite plate showed an excellent agreement with past results. The study shows that as the length to thickness ratio (l/t) was increased, critical loads increased as well. Further, the critical loads for the angle-ply BFRCs were higher than the cross-ply counterparts of the same thickness. Similar pattern of behaviour can be seen for the post-buckling paths of the BFRCs.
Accelerated Non-Coaxial Rotating Flow of MHD Viscous Fluid with Heat and Mass Transfer
Authors: Noranuar W N N , Qushairi Mohamad A , Shafie S , Khan I 
Published: March 2021

Abstract
An exact analysis on heat and mass transfer of mixed convection MHD viscous fluid flow due to accelerated non-coaxial rotation is analyzed. This analysis is considered through a porous medium. The rotation and buoyancy forces involved in this problem give effects on the fluid motion. Dimensional momentum, energy and concentration equations are presented in partial differential equations with initial and boundary conditions which then are reduced into non-dimensional form by introducing non-dimensional variables. This problem is analytically solved by using Laplace transform method and the exact solution obtained for velocity, temperature and concentration profile are graphically plotted in order to investigate the impact of Grashof number Gr, modified Grashof number Gm, Prandtl number Pr and Schmidt number Sc as well as accelerated, magnetic and porosity parameter on its behavior. The results show that the increasing acceleration parameter raises the velocity profile while increasing of Prandtl number and Schmidt number leads to a fall in velocity profile. A verification of obtained solution is conducted by comparing present results with published results and it was found to be in a good agreement.
Debris Flow Numerical Simulation Model Comparison with Field Events in Kuala Kubu Baru and Lentang, Malaysia
Authors: Kasim N , Taib K Abu , Maturidi A M A M , Wan Azahar W N A , Masjuki S A 
Published: March 2021

Abstract
Debris flow is one of Malaysia’s natural disasters which could cause casualties and serious infrastructure damage. Precisely predicting the factors associated with the occurrence of debris flow such as the run-out lengths, velocities and thickness of alluvial deposits can greatly mitigate damage, minimize or even avoid the aftermaths of the occurrence. Applying numerical simulation models explaining debris flow deposition would be a valuable tool in forecasting potential debris flow activity and providing criteria for designing protective measures. Comprehensive studies of available records of past debris flow events from relevant sources and site investigations have been carried out in order to assemble field information for the particular debris flow event in Malaysia. A number of calamitous debris flow events occurred in Malaysia have been closely observed and studied. The well-documented events, i.e. Lentang and Kuala Kubu Baru debris flow disasters occurred on 2nd November 2004 and 10th November 2003, respectively were simulated using the Kanako 2D (Ver.2.04) simulation model software. The results obtained from the numerical simulation model were compared with the real events in order to evaluate their predictive capabilities. The results showed an accuracy of more than 93% was obtained from the simulation model as compared to the real in-situ measurements. A positive simulation result will become a valuable method to predict potential debris flow hazard behavior of the same type and characteristics.
Solution for Sand Production Problem in Oil and Gas well
Authors: Subbiah S K , Mohamad-Hussein A , Samsuri A , Jaafar M Z , Chen Y R , Pearce A , Paramanathan R N , Kumar R R 
Published: March 2021

Abstract
Sandstone reservoir rock failure due to hydrocarbon extraction and pore pressure reduction can induce phenomenon called sand production. Even though sand production may increase the overall productivity especially in heavy oil, it also may cause other negative impact such as equipment erosion which can lead to loss of integrity that can eventually induce hydrocarbon leakage. Thus, safety factors need to be considered before deciding if sand production can be allowed in the well. Operators must be prepared for any additional cost for special well completion plan if their well is sanding candidate. Therefore, predicting the sand production ahead of field development plan is smarter exercise for better return of investment. Estimating where and when sand production will occur can be achieved by conducting fit for purpose geomechanical modelling for the specific reservoir. Summary of the methodology is discussed in the paper which can help completion engineer to make decision in selecting best completion. Data from a gas field and well are used in this paper adopting the suggested methodology. The results from the study can predict when and where sand production will occur and the level of severity. The study also recommends simple solution to avoid any sand production by optimising perforation phasing and its geometry.