bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurement of axial field distribution in a W-band extended interaction resonant cavity based on perturbation technique
Authors: Xu Che , Meng Lin , Wang Bin , Qin Yu , Bi Liangjie , Chang Zhiwei , Peng Ruibin , Li Hailong , Yin Yong
Published: September 2020

The theoretical analysis and the experiment of perturbation techniques to the quantitative measurement of electric field characteristics in a 94 GHz extended interaction resonant cavity (EIRC) are described. Parameters such as the observed reflection coefficient (S11) and resonant frequency at the disturbance point can be adopted to determine the Q-factor, relative electric field intensity, and distribution of the EIRC. In the experiment stage, the frequency deviation characteristics of the tested EIRC under the influence of the metallic sphere are consistent with the simulation results, and the relative error of the frequency deviation is 4.40%. This provides an effective solution for studies of the performance monitoring of millimeter–submillimeter-wave electronic devices and the exploration of high-frequency material science.
Transport of blood particles: Chaotic advection even in a healthy scenario
Authors: Silva I. M. , Schelin A. B. , Viana R. L. , Caldas I. L.
Published: September 2020

We study the advection of blood particles in the carotid bifurcation, a site that is prone to plaque development. Previously, it has been shown that chaotic advection can take place in blood flows with diseases. Here, we show that even in a healthy scenario, chaotic advection can take place. To understand how the particle dynamics is affected by the emergence and growth of a plaque, we study the carotid bifurcation in three cases: a healthy bifurcation, a bifurcation with a mild stenosis, and the another with a severe stenosis. The result is non-intuitive: there is less chaos for the mild stenosis case even when compared to the healthy, non-stenosed, bifurcation. This happens because the partial obstruction of the mild stenosis generates a symmetry in the flow that does not exist for the healthy condition. For the severe stenosis, there is more irregular motion and more particle trapping as expected.
Reduction of hysteresis loss in soft magnetic composites under transverse magnetic field
Authors: Feng S. J. , Ni J. L. , Hu F. , Kan X. C. , Lv Q. R. , Yang Y. J. , Liu X. S.
Published: September 2020

A method to reduction hysteresis loss of soft magnetic composites (SMCs) is reported in this Letter. It is found that the power loss of SMCs reduces about 1/3 at the expanse of less than 10% decreases of permeability when a transverse magnetic field is applied in the SMC core. This power loss reduction comes from the decrease in hysteresis loss of composites, and this reduction is influenced by transverse magnetization state. This hysteresis loss reduction is attributed to domain wall displacements and spin rotations being completely locked in the direction of the transverse field, and this effect has great application potential in high-power electrical systems.
Interlayer exciton valleytronics in bilayer heterostructures interfaced with a phase gradient metasurface
Authors: Sohoni Mandar , Jha Pankaj K. , Nalabothula Muralidhar , Kumar Anshuman
Published: September 2020

Interlayer excitons in bilayer heterostructures of two-dimensional semiconductors have opened a new platform for valley physics and optoelectronic applications owing to several unique properties. Here, we theoretically demonstrate the coherent manipulation of the interlayer excitonic valley degree of freedom in a transition metal dichalcogenide heterobilayer interfaced with a phase gradient metasurface. We harness the peculiar out-of-plane component of polarization of interlayer excitons in conjunction with the anisotropy of the vacuum of the electromagnetic field enabled by the metasurface to induce coherent coupling between mutually orthogonal interlayer excitonic optical selection rule. This coupling leads to a much larger domain within the valley psuedo-spin Bloch sphere being accessible in these heterostructures. Our proposed route to coherent manipulation of interlayer excitons in bilayer heterostructures with structured interfaces such as a metasurface may pave the way for engineering an array of interacting quantum emitters in Moiré heterostructures for chip-scale quantum information science.
Origin of oblique optical axis of electrically tunable focusing lenses arising from initial anisotropic molecular tilts under a symmetric electric field. I
Authors: Wang Yu-Jen , Lin Yi-Hsin , Reshetnyak Victor , Cakmakci Ozan
Published: September 2020

The optical axes of electrically tunable liquid crystal (LC) lenses are usually tilted, and the corresponding asymmetric wavefront aberrations hinder the lenses from being diffraction-limited. Looking back at the literature studies since 1979, researchers used different approaches to compensate the tilting of the optical axis for achieving a perfect lens, or they utilized the intrinsically asymmetric wavefront aberration as a physical-planar free-form optics. However, the physics behind axis tilting has not been discussed yet, and the origin of the oblique optical axes of LC lenses in terms of anisotropic properties of molecules requires an investigation. In this paper, we study the origin of the asymmetrical tilting of optical axes of LC lenses. We found that the initial anisotropic molecular tilts (the so-called pretilt angle) result in the dielectric torque difference even under a rotationally symmetric electric field. Moreover, it is discovered that the rotational symmetry of the wavefront can be broken by generating uneven tilt angles of the LC molecules even though the electric potential is rotationally symmetric. Numerical results are presented and discussed to illustrate the mechanism.
Optimizing the performance of an active grid to generate high intensity isotropic free stream turbulence
Authors: Shet C. S. , Cholemari M. R. , Veeravalli S. V.
Published: September 2020

We present an optimized procedure for generating isotropic, homogeneous, high intensity turbulent flows behind an active grid. The double random protocol (R. E. G. Poorte, “On the motion of bubbles in active grid generated turbulent flows,” Ph.D. thesis, University of Twente, 1998 and subsequent works) used for operating the active grid [H. Makita, “Realization of a large-scale turbulence field in a small wind tunnel,” Fluid Dyn. Res. 8, 53 (1991)] is optimized based on the tip speed ratio α ≡Vtip⟨U⟩=2πΩC⟨U⟩, where Vtip is the speed of the active grid winglet at its tip, 2C is the winglet chord length, Ω is the mean winglet rotational speed, and U is the mean flow speed. A systematic assessment of the resulting turbulent flow is carried out using both hot-wire anemometry (single point and two point) and particle image velocimetry (PIV). It is shown that just using the double random protocol does not guarantee an isotropic flow, and the tip speed ratio of the active grid elements is also important to achieve isotropy. Too high a tip speed ratio, however, results in decreased turbulence intensities. Optimal values of the tip speed ratio, given the trade-off between isotropy and turbulence intensity, are given for the double random protocol. Furthermore, our measurements clearly show that conclusions about the structure and isotropy of active-grid turbulence cannot be based on single-point measurements alone; at the least, two-point or multi-point PIV measurements are essential to evaluate the performance of active grids. This is supported by observing the behavior of longitudinal and transverse correlation functions along the arbitrary directions and the convergence of proper orthogonal decomposition reconstructions to the true value. Interestingly, a simpler test based on the ratio of longitudinal to transverse turbulence intensities appears more robust than the one based on single-point correlations.
Chemical substitution induced half-metallicity in CrMnSb(1−x)Px
Authors: O’Leary Evan , Ramker Adam , VanBrogen Devon , Dahal Bishnu , Montgomery Eric J. , Poddar Shashi , Kharel Parashu , Stollenwerk Andrew J. , Lukashev Pavel V.
Published: September 2020

Half-metallic Heusler alloys have been intensively studied in recent years due to their potential applications in spin-based devices, e.g., in magnetic tunnel junctions. Yet, their properties may be very sensitive to the choice of the substrates, i.e., to the epitaxial strain and interface properties. Here, we report the results of our computational work on the half-Heusler compound CrMnSb(1−x)Px. In particular, we demonstrate that the parent compound CrMnSb is close to a half-metallic material at the optimized lattice parameter, with the onset of the half-metallic bandgap a few meV above the Fermi energy. Moreover, although it undergoes a half-metallic transition under a uniform compression of ∼1.5%, such a transition is absent under epitaxial strain. At the same time, we show that a half-metallic transition could be induced by a chemical substitution of Sb with P, which results in a volume reduction of the unit cell. In particular, 50% substitution of Sb with P leads to a robust half-metallicity in CrMnSb(1−x)Px, with 100% spin polarization being retained at a large range of epitaxial strain. Thus, our results indicate that CrMnSb0.5P0.5 could be grown on different types of substrates, e.g., GaAs, without its electronic properties being detrimentally affected by biaxial strain. In addition, CrMnSb0.5P0.5 exhibits a fully compensated ferrimagnetic alignment, which could be potentially useful in applications where stray magnetic fields are undesirable.
Space-time imaging, magnification, and time reversal of matter waves
Authors: Kolner Brian H.
Published: September 2020

An imaging system is proposed for matter-wave functions, which is based on producing a quadratic phase modulation on the wavefunction of a charged particle, analogous to that produced by a space or time lens. The modulation is produced by co-propagating the wavepacket within an extremum of the harmonic vector and scalar potentials associated with a slow-wave electromagnetic structure. By preceding and following this interaction with appropriate dispersion, which is characteristic of a solution to the time-dependent Schrödinger equation, a system results that is capable of magnifying (i.e., stretching or compressing the space- and time-scales) and time-reversing an arbitrary quantum wavefunction.
Efficient quantum theory for studying cold charge-transfer state dissociations in donor–acceptor heterojunction organic solar cells
Authors: Zhang Longlong , Hao Yuying , Gao Kun
Published: September 2020

In donor–acceptor (D–A) heterojunction organic solar cells, hot and cold charge transfer (CT) states are formed at the interface as the precursor for subsequent charge separations. Hot CT states dissociate easily because they are loosely bound, while for cold CT states, the origin of their high-efficiency charge separations still remains heavily debated. Here, we propose a simple but effective methodology that can be used to simulate the cold CT dissociation process and, thereby, the multiple factors which may essentially affect the charge separation efficiency and can be conveniently investigated. The energy barriers on the path from cold CT to the separated charges are analyzed by calculating the adiabatic potential energy surfaces of the lowest-energy excitonic state. The calculation results indicate that the D–A molecular coupling strength and coupling area, D–A energetic offset, charge carrier delocalizations, interfacial Coulomb screening strength, and interfacial disorders can essentially affect the charge separation efficiency of a cold CT state.
Exit times of a Brownian particle out of a convection roll
Authors: Yin Qingqing , Li Yunyun , Marchesoni Fabio , Debnath Tanwi , Ghosh Pulak K.
Published: September 2020

We numerically investigated the transient dynamics of a passive colloidal particle in a periodic array of planar counter-rotating convection rolls at high Péclet numbers. We discovered that the distributions of first-exit times out of a single convection roll exhibit distinct regimes: an exponential tail, due to the noise-assisted diffusion of the trapped particle from the center toward the edge of the roll, and a peak structure emerging from a power-law background, associated with the transverse and longitudinal Brownian diffusion of the particle within the rolls’ flow boundary layers. These results are interpreted analytically and related to the earlier literature on the topic.
Supermodes of oversized Talbot-type cavities
Authors: Oparina Yu. S. , Savilov A. V. , Shchegolkov D. Yu.
Published: September 2020

The use of a Talbot-type supermode as the primary operating mode can be a means of providing a selective single-mode operation of terahertz electron masers with an oversized beam-wave interaction system. However, as the first step to justifying this approach, it is necessary to show the existence of a set of orthogonal supermodes by which the wave field can be decomposed, to identify the hierarchy and properties of these orthogonal supermodes, and to investigate the issue of their competition. In this paper, all these questions are addressed in the simplest model of a Talbot-type cavity, namely, in a planar 2D cavity with an equidistant spectrum of the transverse wave numbers of the partial waveguide modes. The development of this approach for more complex types of cavities is also briefly discussed.
Applications of Casimir forces: Nanoscale actuation and adhesion
Authors: Palasantzas George , Sedighi Mehdi , Svetovoy Vitaly B.
Published: September 2020

Here, we discuss possible applications of the Casimir forces in micro- and nanosystems. The main part of this paper is devoted to actuation with quantum fluctuations and to the relative contribution of van der Waals and Casimir interactions to adhesion. Switching between the amorphous and crystalline states of phase change materials could generate force contrast sufficient for actuation, though for practical applications, the influence of protective capping layers and volume compression have to be better understood. Resilience against the pull-in instability is also a critical point defined by the material choice, dissipation in the system, and roughness of the surfaces. The adhesion induced by the Casimir forces is omnipresent, and it can play a pivotal role in unwanted stiction demanding deeper understanding. The open problems are the distance upon contact and the relative area of the real contact since both of them control the adhesion. An experiment designed to answer these questions is briefly discussed.
A surface potential-based DC model considering interface trap states for 4H-SiC power MOSFETs
Authors: Liu Yuan , Peng Zijuan , Lu Yudong , Wang Bingqi , Deng Wanling
Published: September 2020

In this paper, a surface potential-based physical model is described for the DC characteristics of 4H-silicon carbide power metal–oxide–semiconductor field-effect transistors. The proposed scheme is based on the charge-sheet model and accounts for the interface charges, which include the fixed oxide charges and the interface-trapped charges. An analytical and effective approximation of the surface potential as a function of gate voltage is proposed, which can serve as a basis for the surface potential-based DC model. Furthermore, it has been demonstrated that the measured I–V characteristics are well reproduced by the proposed drain current model in a wide range of bias voltages and temperatures.
Materials genome evolution of surface plasmon resonance characteristics of Au nanoparticles decorated ZnO nanorods
Authors: Yen Sheng-Che , Chen Yu-Lin , Su Yen-Hsun
Published: September 2020

The effect of surface plasmon resonance (SPR) from noble metal nanostructures such as gold nanoparticles (Au NPs) has been proposed to promote the generation of energetic hot electrons as well as boosting resonant energy transfer, thereby resulting in significantly enhancing solar-light harvesting and energy conversion efficiency. Herein, Au NPs decorated zinc oxide nanorods with plasmonic metal–semiconductor heterostructures have been synthesized through UV/Ozone treatment. Absorption, light-to-plasmon conversion efficiency, plasmon-to-hot electron conversion efficiency, and quality (Q)-factor of Au@ZnO nanocomposites are further characterized in order to understand the related SPR effect from various aspects. Simultaneously, the use of machine learning (ML) as an artificial intelligence data-driven method to derive an alternative predictive model for evaluating the relationship between synthesis and properties of materials has been adopted. In this regard, we collect only a limited supply of experimental dataset as training data to establish the predictive model with an artificial neural network incorporating genetic algorithm. According to the results from experimental datasets and the proposed predictive model, our analysis has revealed that the conversion efficiency and Q-factor associated with the SPR effect from Au@ZnO nanocomposites can be efficiently evaluated through ML, which has potential application in plasmon-sensitized solar cells and plasmonic lasers in the future.
Frame-invariant formulation of novel generalized Newtonian fluid constitutive equation for polymer melts
Authors: Zatloukal Martin
Published: September 2020

In this work, the frame-invariant formulation of a new generalized Newtonian fluid (GNF) constitutive equation is proposed. Viscosity is considered as a specific function of the second and third invariant of the strain rate tensor and of the second invariant of the objective velocity gradient. The GNF model was successfully tested using experimental data taken from the open literature for different high and low density polyethylene melts with varying amounts of long-chain branches utilizing steady-state shear, uniaxial, and planar extensional viscosities plotted as a function of the strain rate.
Analytical modeling of transport phenomena in heterojunction triple metal gate all around tunneling field effect transistor
Authors: Mahdia Marjana , Mohd Khosru Quazi Deen
Published: September 2020

An analytical model for the transport phenomena of a heterojunction triple metal gate all around tunneling field effect transistor (HTM GAA TFET) is developed for the first time in this paper. The continuous surface potential profile of the staggered-gap aligned heterojunction device is achieved by solving Poisson’s equation, and then, Kane’s model for band to band tunneling is used to derive the drain current of the device. The comparison between the modeling results and Technology Computer Aided Design (TCAD) simulation results with the GaAs0.5Sb0.5/In0.53Ga0.47As heterojunction stems satisfactory consistency. The robust and compatible model approaches the surface potential, electric field, band to band tunneling generation rate, and drain current in an HTM GAA TFET in a methodical manner. The influences of gate oxide thickness, gate oxide dielectric constant, and gate metal work functions on the performance of the considered device are also investigated. To achieve an impactful perspective, the subthreshold swing, Ion/Ioff ratio, and threshold voltage of the device are reviewed as well.
Targeting the histone demethylase PHF8-mediated PKCα-Src-PTEN axis in HER2-negative gastric cancer
Authors: Tseng Lin-Lu , Cheng Hsin-Hung , Yeh Ta-Sen , Huang Shih-Chiang , Syu Ya-Yun , Chuu Chih-Pin , Yuh Chiou-Hwa , Kung Hsing-Jien , Wang Wen-Ching
Published: September 2020

Significance

Gastric cancer (GC), a deadly malignancy in the world, particularly in East Asia, remains a major clinical challenge given a lack of effective targeted treatments for advanced HER2-negative cases (80 to 88%). This work uncovers a PHF8/c-Jun-mediated axis that upregulates the expression of PKCα, triggering Src activation and PTEN inhibition. High PHF8-PKCα expression predicts worse prognosis in GC. Importantly, targeting the PKCα-Src-PTEN pathway by pharmacological inhibitors represents a new intervention strategy for HER2-negative gastric cancers.
CD8 T cells drive anorexia, dysbiosis, and blooms of a commensal with immunosuppressive potential after viral infection
Authors: Labarta-Bajo Lara , Gramalla-Schmitz Anna , Gerner Romana R. , Kazane Katelynn R. , Humphrey Gregory , Schwartz Tara , Sanders Karenina , Swafford Austin , Knight Rob , Raffatellu Manuela , Zúñiga Elina I.
Published: September 2020

Significance

Infections are known to perturb intestinal microbiome composition, but the underlying mechanisms and the implications of specific commensal species for antiviral immunity remain largely unknown. Here, we found that infection of mice with a fast-spreading and persistent, but not slow-spreading acute, viral isolate induced profound microbial dysbiosis, including blooming of
Akkermansia muciniphila
, that was largely caused by CD8 T cells and/or CD8 T cell-induced anorexia. Notably, administration of
A. muciniphila
into infected mice attenuated selected aspects of CD8 T cell responses, supporting its immunosuppressive potential in this context. Our findings bring about a role for CD8 T cells in promoting anorexia and microbial shifts after infection, including the enrichment of a fasting-associated commensal that can attenuate CD8 T cell responses.
Convergent molecular, cellular, and cortical neuroimaging signatures of major depressive disorder
Authors: Anderson Kevin M. , Collins Meghan A. , Kong Ru , Fang Kacey , Li Jingwei , He Tong , Chekroud Adam M. , Yeo B. T. Thomas , Holmes Avram J.
Published: September 2020

Significance

Major depressive disorder is a debilitating condition with diverse neuroimaging correlates, including cortical thinning in medial prefrontal cortex and altered functional connectivity of cortical association networks. However, the molecular bases of these imaging markers remain ambiguous, despite a need for treatment targets and mechanisms. Here, we advance cross-modal approaches to identify cell types and gene transcripts associated with depression-implicated cortex. Across multiple population-imaging datasets (combined
N
≥ 23,723) and ex vivo patient cortical tissue, somatostatin interneurons and astrocytes emerge as replicable cell-level correlates of depression and negative affect. These data identify transcripts, cell types, and molecular processes associated with neuroimaging markers of depression and offer a roadmap for integrating in vivo clinical imaging with genetic and postmortem patient transcriptional data.
Strain engineering of the charge and spin-orbital interactions in Sr
2
IrO
4
Authors: Paris Eugenio , Tseng Yi , Pärschke Ekaterina M. , Zhang Wenliang , Upton Mary H. , Efimenko Anna , Rolfs Katharina , McNally Daniel E. , Maurel Laura , Naamneh Muntaser , Caputo Marco , Strocov Vladimir N. , Wang Zhiming , Casa Diego , Schneider Christof W. , Pomjakushina Ekaterina , Wohlfeld Krzysztof , Radovic Milan , Schmitt Thorsten
Published: September 2020

Significance

Understanding the relationship between entangled degrees of freedom (DOF) is a central problem in correlated materials and the possibility to influence their balance is promising toward realizing novel functionalities. In Sr
2
IrO
4
, the interaction between spin–orbit coupling and electron correlations induces an exotic ground state with magnetotransport properties promising for antiferromagnetic spintronics applications. Moreover, the coupling between orbital and spin DOF renders the magnetic structure sensitive to the Ir–O bond environment. To date, a detailed understanding of the microscopic spin-lattice and electron–phonon interactions is still lacking. Here, we use strain engineering to perturb the local lattice environment and, by tracking the response of the low-energy elementary excitations, we unveil the response of the microscopic spin and charge interactions.
Human-nature relationships in experiential meaning: transitivity system of Chinese from an ecolinguistic perspective
Authors: Zhang Ruijie , He Wei
Published: September 2020

Following a systemic functional approach to ecolinguistic studies, this study explores the Chinese transitivity system's interpretative potential in revealing the dynamic relationship between human beings and their living places. The research extends the transitivity system under the ethical framework of Ecological Sense of Place, drawing on theories from human geography and traditional Chinese philosophies. Within such a premise, the system of process configurations and participants of Chinese process types are reinterpreted, arguing that both the participant and the process should be judged through an ecological lens concerning their function in construing the human-place relationships. The scale of influence and environmental stances of Participant roles is addressed, following a belief that every entity contains participative potential as -er/-ed role of a process. Place as a circumstantial role is expressly acknowledged for their contribution to circumscribe people-place relationships. Regarding the process types, a reconsideration of their emotive, cognitive and agentive features is proposed to reveal the embedded attitudes toward places. These observations extend the knowledge on how the transitivity system can be refined to show the speaker/writer's attitude toward the ecology and its further influences on the collective understanding of human-nature relationships.
STRIPAK regulates Slik localization to control mitotic morphogenesis and epithelial integrity
Authors: De Jamblinne Camille Valérie , Decelle Barbara , Dehghani Mehrnoush , Joseph Mathieu , Sriskandarajah Neera , Leguay Kévin , Rambaud Basile , Lemieux Sébastien , Roux Philippe P. , Hipfner David R. , Carréno Sébastien
Published: September 2020

Proteins of the ezrin, radixin, and moesin (ERM) family control cell and tissue morphogenesis. We previously reported that moesin, the only ERM in Drosophila, controls mitotic morphogenesis and epithelial integrity. We also found that the Pp1-87B phosphatase dephosphorylates moesin, counteracting its activation by the Ste20-like kinase Slik. To understand how this signaling pathway is itself regulated, we conducted a genome-wide RNAi screen, looking for new regulators of moesin activity. We identified that Slik is a new member of the striatin-interacting phosphatase and kinase complex (STRIPAK). We discovered that the phosphatase activity of STRIPAK reduces Slik phosphorylation to promote its cortical association and proper activation of moesin. Consistent with this finding, inhibition of STRIPAK phosphatase activity causes cell morphology defects in mitosis and impairs epithelial tissue integrity. Our results implicate the Slik–STRIPAK complex in the control of multiple morphogenetic processes.
Unified modelling of low-current short-length arcs between copper electrodes
Authors: Baeva M , F Boretskij V , Gonzalez D , Methling R , Murmantsev O , Uhrlandt D , Veklich A
Published: September 2020

In this work, we present for the first time a unified model of a low-current short-length arc between copper electrodes. The model employs one-dimensional fluid description of the plasma in argon and copper vapour at atmospheric pressure and the heat transfer in the electrodes made of copper. The solution of the particle and energy conservation of electrons and heavy particles is coupled with the solution of the Poisson equation, from which the self-consistent electric field is obtained. The operation of the non-refractory cathode is based on thermo-field emission. Heat fluxes from the plasma to the electrodes are considered so that a phase change and evaporation from the cathode and a release of copper atoms into the plasma are taken into account. The influence of the copper atoms and ions on the plasma properties is analysed and discussed. The model’s predictions are compared with experimental data and a qualitative agreement is obtained besides the restrictions of the one-dimensional fluid model.
Optical absorption coefficient calculations of GaSb/GaAs quantum dots for intermediate band solar cell applications
Authors: Kunrugsa Maetee
Published: September 2020

Absorption coefficients of GaSb/GaAs quantum dots (QDs) are calculated by the 8-band strain-dependent k· p method and Fermi’s golden rule. A more realistic but simple approach to model the QD ensemble with wetting layer is described. Effects of the QD size and density, and the GaAs spacer thickness for multi-stacked QDs on absorption characteristics are studied. Absorption spectra of the single QD, single layer of QDs, and multi-stacked QDs are presented and discussed. Interband absorption is found to be more intense than intraband absorption. The calculated absorption spectra are brought into the drift-diffusion model coupled with rate equations to determine the current density-voltage curves of the GaSb/GaAs QD solar cells, which are compared with measured data in literature for validation. The models proposed in this work are capable of predicting the short-circuit current density and open-circuit voltage of real devices, and would have the potential to investigate the impact of doping and position of the QD layers, which is necessary for intermediate band solar cell analysis and design.
Interacting hadron resonance gas model in magnetic field and the fluctuations of conserved charges
Authors: Kadam Guruprasad , Pal Somenath , Bhattacharyya Abhijit
Published: September 2020

In this paper we discuss the interacting hadron resonance gas (HRG) model in presence of a constant external magnetic field. The short range repulsive interaction between hadrons are accounted through Van der Waals excluded volume correction to the ideal gas pressure. Here we take the sizes of hadrons as r

π
(pion radius) = 0 fm, r
K (kaon radius) = 0.35 fm, r
m (all other meson radii) = 0.3 fm and r
b (baryon radii) = 0.5 fm. We analyse the effect of uniform background magnetic field on the thermodynamic properties of interacting hadron gas. We especially discuss the effect of interactions on the behaviour of magnetization of low temperature hadronic matter. The vacuum terms have been regularized using magnetic field independent regularization scheme. We find that the magnetization of hadronic matter is positive which implies that the low temperature hadronic matter is paramagnetic. We further find that the repulsive interactions have very negligible effect on the overall magnetization of the hadronic matter and the paramagnetic property of the hadronic phase remains unchanged. We have also investigated the effects of short range repulsive interactions as well as the magnetic field on the baryon and electric charge number susceptibilities of hadronic matter within the ambit of excluded volume HRG model.
3D point cloud capture method for underwater structures in turbid environment
Authors: Lin Haitao , Zhang Hua , Li Yonglong , Wang Haoran , Li Jialong , Wang Shuang
Published: September 2020

Underwater structure inspections are essential for infrastructure maintenance, such as hydraulic facilities, bridges, and ports. Due to the influence of turbidity, dark light, and distortion, the traditional methods cannot satisfy the requirements of on-site inspection applications. This paper proposed a methodology of the point cloud data capture in the turbid underwater environment. The method consisted of an acquisition device, a distortion correction algorithm, and a parameter optimization approach. The acquisition device was designed by composing a silt-removing module, a structured light camera module, and a clear water replacement module, which can integrate with an underwater inspection robot. The underwater multi-medium plane refraction distortion model was established through analysis, and a refraction correction algorithm was provided to correct the distortion. To obtain the maximum field of view of the point cloud, the nonlinear optimization approach was used to select the medium material and thickness. After the real experiments using the Intel RealSense sr300 depth camera, maximum measuring distance could range up to 253 mm in water, the accuracy of the point cloud of the underwater target objects was ±3.77 mm, and the maximum error was 8.76%. Compared with other methods, this method was more suitable for 3D point cloud capture in the turbidity environment.
Complementary amide-based donor–acceptor with unique nano-scale aggregation, fluorescence, and band gap-lowering properties: a WORM memory device
Authors: Ghosh Tanmoy , Mondal Somrita , Maiti Rituparna , Nawaz Sk Masum , Ghosh Narendra N , Dinda Enakshi , Biswas Amrita , Maity Suman Kumar , Mallik Abhijit , Maiti Dilip K
Published: September 2020

Organic fluorescent semiconducting nanomaterials have gained widespread research interest owing to their potential applications in the arena of high-tech devices. We designed two pyrazaacene-based compounds, their stacked system, and the role of gluing interactions to fabricate nanomaterials, and determined the prospective band gaps utilizing the density functional theory calculation. The two pyrazaacene derivatives containing complementary amide linkages (–CONH and –NHCO) were efficiently synthesized. The synthesized compounds are highly soluble in common organic solvents as well as highly fluorescent and photostable. The heterocycles and their mixture displayed efficient solvent dependent fluorescence in the visible region of the solar spectrum. Notably, the compounds were associated through complementary NH•••O = C type hydrogen bonding, π–π stacking, and hydrophobic interactions, and thereby afforded nanomaterials with a low band gap. Fascinatingly, the fabricated stacked nanomaterial system exhibited resistive switching behavior, leading to the fabrication of an efficient write-once-read-many-times memory device of crossbar structure.
Observational evidence of magnetic reconnection in a coronal bright point
Authors: Ning Zong-Jun , Li Dong , Zhang Qing-Min
Published: September 2020

Magnetic reconnection is considered to be the fundamental process by which magnetic energy is converted into plasma or particle kinetic energy. Magnetic reconnection is a widely applied physics model to explain the solar eruption events, such as coronal bright points (CBPs). Meanwhile, it is an usual way of the solar physics research to look for the observational evidences of magnetic reconnection in the solar eruption events in order to support the model. In this paper, we have explored the evidences of magnetic reconnection in a CBP observed by the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO) at NOAA No. 11163 on 2011 March 5. Our observations show that this event is a small-scale loop system in active regions that have similar size as a traditional CBP and it might shed light on the physics of a traditional CBP. This CBP is bright in all nine AIA wavelengths and displays a flaring development with three bursts intermittently. Each burst exhibits a pair of bi-directional jets almost along a line. They originate from the same position (CBP core), then move in the opposite directions. Our findings are well consistent with the magnetic reconnection process by which the bi-directional plasma outflows are produced and radiate the bi-directional jets detected by SDO/AIA. These facts further support the conclusion that the CBP is produced by the magnetic reconnection process.
Education Innovations through Mobile Learning Technologies for the Industry 4.0 Readiness of Tertiary Students in Malaysia
Authors: Karim R A , Adnan A H M , Salim M S A M , Kamarudin S , Zaidi A
Published: September 2020

The formal education sphere is one that is dynamic and ever-changing, even more so with current developments in technologies of teaching and learning. The process of education needs new innovations to keep pace with these rapid developments, particularly for tertiary students on the cusp of radical Industry 4.0 ‘disruptions’ that will permeate all social and personal domains in human societies around the globe. One area where innovation is happening is in the implementation of mobile learning technologies for tertiary college and higher learning institutions. The study examines why and how tertiary students utilize their mobile devices in the education setting as both a conduit and catalysts for e-learning. Tertiary students find the utilize of mobile devices easy and natural, thus helping them to learn anytime, anywhere. Today, the popularity of mobile practices amongst tertiary education is steadily growing and they are now able to utilize their mobile devices for a myriad of activities from developing websites to creating mobile apps to acquiring knowledge non-stop. Mobile application for learning is expected to be prevalent in forthcoming, as more devices procured by the younger generation. This study examines results from a survey on the perceptions and practices of mobile learning for Malaysian tertiary students. A quantitative research methodology was adopted to analyse data; results demonstrate that these students have positive perceptions towards mobile technology utilize in learning, and they actively and autonomously utilize mobile devices to enhance their experience of learning.
Development of IoT Based Weather Reporting System
Authors: Pauzi A F , Hasan M Z
Published: September 2020

Weather forecast these days is unpredictable too be exact because of the climate changes drastically over weather. In cause of that, Weather Reporting System is mostly used to monitor the continuously changing climatic and weather conditions over controlled areas likes house, industry, agriculture and etc. in real time monitoring. Internet of Things (IoT) platform use is ThingSpeak it’s should be able displaying the weather parameters and the information will visible wherever in the world and it’s also displaying on the OLED with two-way microcontroller communication via Wi-Fi hotspots. The condition of some particular place that be reported by satellite weather report system does not give the exact condition. However, the problem occurs when needed the accurate weather report for current time. With weather reporting system all weather parameters sensor will be controlled by ESP32 microcontroller as the server that will send all the data collected by sensors to the database by ThingSpeak and will visible anywhere in the world and also display on OLED that use Wemos D1 mini as its microcontroller and a client. This data then will be compared with the weather forecast data and statistics made by forecast station. All data collected will be also saved in google sheet format by IFTT tool for easier to analyse the data. This system will monitor the changes of weather condition happening over the environment and then provides the users fastest way to access the information from anywhere.
Design of a 3D Printed UWB Antenna for a Low-Cost Wireless Heart and Respiration Rate Monitoring
Authors: ‘A Alias N , Shaharum S M , Karim M S A
Published: September 2020

This paper introduces an ultra-wideband (UWB) horn antenna for a low-cost wireless heart and respiration rate monitoring that is manufactured by a 3D printing technology. The proposed design operates within 3.1-10.6 GHz. The horn antenna is designed within the 15-dB gain which is sufficient to be used in medical system. The horn was designed to calculate the gain in MATLAB using an approximation method and simulated using CST Microwave Studio. The proposed antenna is 4-6 GHz (G-Band) operating. A printed antenna which is supported by WR-187 rectangular waveguide is fabricated using low cost polylactic acid (PLA). The surface is then metalized using copper tape on the inside. The simulation result of reflection coefficient for different conductivity and thickness of coating metal is compared, the developed 3D printed antenna successfully operated within given frequency range of 3-11 GHz which covered the ultra-wideband frequency range.
The Combination of Autoregressive Integrated Moving Average (ARIMA) and Support Vector Machines (SVM) for Daily Rubber Price Forecasting
Authors: Jing Jong Lai , Ismail Shuhaida , Mustapha Aida , Helmy Abd Wahab Mohd , Zulkarnain Syed Idrus Syed
Published: September 2020

Natural rubber (NR) price is easily affect by the long term and short term exchange rate of developments on supply and demand sides, as well as the effects of exchange rates. Due to the fact that monthly, quarterly, and annually data have underwent the smoothing technique, it may has missed out some of the important characteristics or information describing the rubber price. Since the NR price is changing daily, therefore, this study focuses on the predicting the future daily prices. A combination models of Autoregressive Integrated Moving Average (ARIMA) and Support Vector Machine (SVM) is proposed in order to capture the future value of NR prices. The experimental results show that the proposed model performs the best whereby it has under predicted by 6.31% with the r value of 0.9976 compared to single ARIMA and SVM models. As the results, the combination model shows to be an effective tools in improving the forecasting accuracy by reducing the model forecast error.
Binary Time-Frequency Mask for Improved Malay Speech Intelligibility at Low SNR Condition
Authors: Jamal Norezmi , Fuad N. , Sha’bani MNAH , Helmy Abd Wahab Mohd , Zulkarnain Syed Idrus Syed
Published: September 2020

A binary masking is often seen as a medium to enhance speech signal especially in hearing aid and speech recognition applications due to its simplicity and efficient approach for supervised source separation. High intelligibility could be obtained by applying the binary time-frequency masking to noisy speech signal. Since the issue of linear filtering algorithms might affect the intelligibility of noisy speech signal, so, this paper presents the binary time-frequency mask for improved Malay speech intelligibility at low SNR condition. The clean Malay speech signals that were contaminated by car and train noise with different signal to noise ratio (SNR) and local criterion (LC) level in forming the binary mask are analysed. The performance of intelligibility improvement was evaluated using a normalized sub band enveloped correlation (nSec). Overall results showed that the proposed approach produces slightly improved speech intelligibility at low SNR value.
Query Operation in Trader Service: LDAP Directory versus Database
Authors: Muchtar Farkhana , Lukuman Saheed Ajibade , Helmy Abd Wahab Mohd , Zulkarnain Syed Idrus Syed
Published: September 2020

This study inspects the capability of LDAP in improving the performance of query operation in the trading service. Thus, an experiment is conducted to distinguish the performance result gained from a trading service which uses LDAP with a trading service that uses relational database as its backend storage. From the outcome of the experiment conducted, we verified that a trading service that use LDAP provide a better performance as compared to a trading service that relational database.
Application Research of Mathematical Model in Tallo River Flood Analysis
Authors: Triselia Guhar Maria , Saleh Pallu Muhammad , Putra Hatta Mukhsan
Published: September 2020

Rivers are natural elements, and rivers play an important role in shaping the style of the community. The Tallo River in Makassar has advantages in economy, entertainment and transportation. But almost every year, the area along the river is always flood. this probelm can be solved by examine the phenomena and conditions of the level of flood watersheds vulnerability using hydrological approach through Muskingum kinematic methods, which is a common flood routing methods. By approaching the hydrological conditions of the Tallo river watershed, the results of this study are expected to provide the best alternative treatment options. The flood discharge value is executed based on the rainfall data that collected from three stations along the river namely Hasanuddin, Malino and Senre. After that, the flood discharge plan is conducted to obtaing the outflow value by using the inflow value through Muskingum method. The length of the river considered in this study is about 20 km, and it is divided into 5 segments every 4 km. The x value is between 0.1 and 0.3, and the K value is between 0.16-0.57. The obtained maximum flood discharge from the Muskingum calculation for the 2-year return period occurred at 801,330 m3/sec with an X value = 0.1 and K = 0.58.
Soap Making Machine Development For Home Appliances
Authors: Maidin N.A. , Rahman M.H.A , Ahmad M.N. , Osman M.H. , Wahid M.K. , Ahmad U.H. , Tan H.S. , Anuar N.F.B.W.
Published: September 2020

Nowadays, most of the time people will using cooking oil to bake, fry and other type of cooking. There are many types of cooking oil such as olive oil, palm oil, canola oil, vegetable oil and etc. Normally, only two or three times the oil can be used for fry. After that, the oil will throw away. The disposal of used cooking oil is an important factor for the waste-management. Most people will dump the used cooking oil in the kitchen sink. This will led to blockage to the pipe and contaminate water. Without people realise, used cooking oil can be recycled in to soap for general purposes. The aim of this research is to develop a semi-automatic machine for making soap by using used cooking oil as main ingredients. There were a lots of process involved such as how to gain the voice of customer (VOC), concept selection, detail design, fabrication and testing process in order to verify the quality and time taken to produce the soaps. This machine can be used in every kitchen of household and not for mass production. Meanwhile, user can make their own soap for general purpose such as to wash floor, car and drain. Moreover, this can save environment.
Simulation Study of Metamaterial Effect towards Ultra Wide Band Antenna
Authors: Amirah Othman Nur , Aminudin Jamlos Mohd , Azani Mustafa Wan , Zulkarnain Syed Idrus Syed
Published: September 2020

In this paper, the design of a metamaterial ultra-wideband (UWB) antenna with a goal towards application in microwave imaging systems for detecting unwanted cells in human tissue, such as in cases of breast cancer, heart failure and brain stroke detection is proposed. The metamaterial unit cell is constructed using circular split ring resonator (CSRR) technique and wire, to attain a design layout that simultaneously exhibits both a negative magnetic permeability and a negative electrical permittivity and attached as superstrate in front of the UWB antenna. This design results in an astonishing negative refractive index that enables amplification of the radiated power of this reported antenna, and therefore, high antenna performance. A Rogers (RT5880) substrate material is used to design and print this reported antenna, and has the following characteristics: thickness of 0.51 mm, relative permeability of one, relative permittivity of 2.70 and loss tangent of 0.02. The metamaterial antenna is design to be operated at frequency between 300MHz to 30GHz which is suitable for biomedical application such as Microwave Imaging. The overall metamaterial antenna size is 90 mm × 50 mm × 0.51 mm. The design and simulation has been carried out using Computer Simulation Technology Microwave Studio (CST MWS).
Hybrid Bacterial Foraging Sine Cosine Algorithm for Solving Global Optimization Problems
Authors: Mohammad Shuhairie , Nor Kasruddin Nasir Ahmad , Abdul Ghani Nor Maniha , Mohd Taufika Raja Ismail Raja , Azwan Abd Razak Ahmad , Falfazli Mat Jusof Mohd , Amira Mhd Rizal Nurul
Published: September 2020

This paper proposes a new hybrid algorithm between Bacterial Foraging Algorithm (BFA) and Sine Cosine Algorithm (SCA) called Hybrid Bacterial Foraging Sine Cosine Algorithm (HBFSCA) to solve global optimization problems. The proposed HBFSCA algorithm synergizes the strength of BFA to avoid local optima with the adaptive step-size and highly randomized movement in SCA to achieve higher accuracy compared to its original counterparts. The performances of the proposed algorithm have been investigated on a set of single-objective minimization problems consist of 30 benchmark functions, which include unimodal, multimodal, hybrid, and composite functions. The results obtained from the test functions prove that the proposed algorithm outperforms its original counterparts significantly in terms of accuracy, convergence speed, and local optima avoidance.