bluuebunny/crossref_metadata_2025 huggingface dataset:
Software Defined Networking Automation Using OpenDaylight and Network Virtualization for security and scalability: a network enterprise case
Authors: Jaff Aws
Published: February 2022

Software Defined Network SDN is a technique that centralized the control plane in one device and the data plane (forward plane) in the other devices connected and communicated via SDN protocols, so these devices will get instructions from a central entity called a controller to manage the network efficiently. The controller generally has a global view of the network topologies and can broadcast any management policy to all devices in the network easily. SDN makes the recent network more responsive and flexibly managed by delivering interoperable and programmable network services to network organizations all around the world. In this work, two real critical scenarios were investigated against other scenarios to manifest the SDN ability to deal with them. Finally, results show that the opted implementation features are better than the others in term of testing parameters.
Hydrogen steelmaking, part 2: competition with other net-zero steelmaking solutions – geopolitical issues
Authors: Birat Jean-Pierre , Patisson Fabrice , Mirgaux Olivier
Published: February 2022

Hydrogen direct reduction is one of the technological process solutions for making steel, explored in the framework of reducing GHG emissions from the steel sector (Net-Zero steel). However, there are many other solutions, which have been explored since the 1980s or earlier. The present paper starts by comparing all these different options in terms of 3 criteria: energy needs, GHG emissions and total production cost of steel. The extensive simulations carried out as part of the ULCOS Program, which are still fully valid, indeed show that, while energy is always rather close to the efficient integrated steel mill benchmark (within 15–20%), there are a series of solutions for significantly cutting GHG emissions, some of which even leading to negative emissions. Two families of solutions can usefully be compared with each other, as they are both based on the use of electricity: hydrogen direct reduction, from green hydrogen generated from green electricity, and electrolysis of iron ore, such as the ΣIDERWIN process, also based on zero-carbon electricity. They are quite close with regards to the 3 above criteria, with a slight advantage for electrolysis. Focusing now on hydrogen steelmaking, the process developed over the last 70 years: the H-Iron process was first explored in 1957 at laboratory level, then it was followed by an industrial first plant in the late 1980s, which did not fully deliver (CIRCORED); a sub-project within ULCOS (2000s) followed, then some projects in Germany and Austria (SALCOS, SUSTEEL, MATOR, based on direct reduction and smelting reduction, 2010s) and then, very recently, occurred an explosion of projects and announcements of industrial ventures, both for generating hydrogen and for producing DRI, located in Europe, Russia and China. Broader questions are then tackled: how much hydrogen will be called upon, compared to today and future needs, regarding in particular H2-e-mobility; carbon footprint and costs; maturity of the various processes; and geopolitical issues, such as possible locations of H2-generation and H2-steel production.
A comparative study on energy performance between different PV/T systems and PV system in a cold highland area in winter
Authors: Gao Zhiyu , Yu Nanyang , Cao Xiaoling , Sun Liangliang , Zhou Jinzhi , Yuan Yanping
Published: February 2022

This paper aims to investigate the influence of active cooling and natural cooling on the electrical performance of photovoltaic (PV) modules in a cold highland area in winter, and the thermal performance of two photovoltaic thermal (PV/T) systems for space heating. A comparative system with exactly the same size of a PV system, liquid-cooled PV/T system, and heat pipe PV/T system was designed and constructed in Ganzi city, China. The energy performance of these systems was tested under real weather conditions for several days. The experimental results show that the PV module can achieve the cooling effect by natural cooling, with a daily average temperature between 30 °C and 40 °C, and an electrical efficiency 3.71% higher than that of active cooling. However, the temperature of naturally cooled PV modules fluctuates drastically with time, and the temperature changes above 10 °C in a short time. The solar energy conversion efficiency of PV/T systems is more than 2.67 times that of a PV system. The heating power of the liquid-cooled PV/T system and heat pipe PV/T system can reach 847.4 and 948.5 W, and the primary-energy saving efficiency can reach 68.8% and 76.7%. A comparison of the intercept efficiency shows that the heat pipe PV/T system has the best energy performance.
Molecular Auger decay rates from complex-variable coupled-cluster theory
Authors: Matz Florian , Jagau Thomas-C.
Published: February 2022

The emission of an Auger electron is the predominant relaxation mechanism of core-vacant states in molecules composed of light nuclei. In this non-radiative decay process, one valence electron fills the core vacancy, while a second valence electron is emitted into the ionization continuum. Because of this coupling to the continuum, core-vacant states represent electronic resonances that can be tackled with standard quantum-chemical methods only if they are approximated as bound states, meaning that Auger decay is neglected. Here, we present an approach to compute Auger decay rates of core-vacant states from coupled-cluster and equation-of-motion coupled-cluster wave functions combined with complex scaling of the Hamiltonian or, alternatively, complex-scaled basis functions. Through energy decomposition analysis, we illustrate how complex-scaled methods are capable of describing the coupling to the ionization continuum without the need to model the wave function of the Auger electron explicitly. In addition, we introduce in this work several approaches for the determination of partial decay widths and Auger branching ratios from complex-scaled coupled-cluster wave functions. We demonstrate the capabilities of our new approach by computations on core-ionized states of neon, water, dinitrogen, and benzene. Coupled-cluster and equation-of-motion coupled-cluster theory in the singles and doubles approximation both deliver excellent results for total decay widths, whereas we find partial widths more straightforward to evaluate with the former method.
Deep learning assisted mechanotyping of individual cells through repeated deformations and relaxations in undulating channels
Authors: Combs Cody , Seith Daniel D. , Bovyn Matthew J. , Gross Steven P. , Xie Xiaohui , Siwy Zuzanna S.
Published: February 2022

Mechanical properties of cells are important features that are tightly regulated and are dictated by various pathologies. Deformability cytometry allows for the characterization of the mechanical properties at a rate of hundreds of cells per second, opening the way to differentiating cells via mechanotyping. A remaining challenge for detecting and classifying rare sub-populations is the creation of a combined experimental and analysis protocol that approaches the maximum potential classification accuracy for single cells. In order to find this maximum accuracy, we designed a microfluidic channel that subjects each cell to repeated deformations and relaxations and provides a comprehensive set of mechanotyping parameters. We track the shape dynamics of individual cells with high time resolution and apply sequence-based deep learning models for feature extraction. In order to create a dataset based solely on differing mechanical properties, a model system was created with treated and untreated HL60 cells. Treated cells were exposed to chemical agents that perturb either the actin or microtubule networks. Multiple recurrent and convolutional neural network architectures were trained using time sequences of cell shapes and were found to achieve high classification accuracy based on cytoskeletal properties alone. The best model classified two of the sub-populations of HL60 cells with an accuracy over 90%, significantly higher than the 75% we achieved with traditional methods. This increase in accuracy corresponds to a fivefold increase in potential enrichment of a sample for a target population. This work establishes the application of sequence-based deep learning models to dynamic deformability cytometry.
Shock wave diagnostics with an ultra-short optical fiber probe
Authors: Zilberman S. , Berkovic G. , Fedotov-Gefen A. , Ravid A. , Paris V. , Schweitzer Y. , Gabay S. , Gillon O. , Saadi Y. , Shafir E.
Published: February 2022

We report a highly localized, rapid-response pressure measurement of a shock wave front in a solid by utilizing a miniature fiber-optic-based probe. The probe used was a 100 μm-long fiber Bragg grating (FBG) inscribed on a standard silica communication fiber, 125 μm in diameter. The optical fiber was embedded within a ceramic zirconia ferrule and was shocked axially by a polycarbonate impactor fired from a gas gun. In a second ferrule, included in the same experiment, a 1 mm long FBG was embedded for comparison. Both FBGs were positioned at the front face of their respective ferrules, in order to sense the region where the shock wave is pristine, with no release waves, and where the stress conditions were expected to be constant for a few hundreds of nanoseconds. A simulation has been performed using LS-DYNA software describing the temporal dependence of the axial stress operating on the zirconia target and the embedded fiber gratings. The reflected spectra of both fiber grating probes were interrogated by an array of wavelength division demultiplexers and 200 MHz InGaAs detectors. Both probes exhibited a wavelength shift that corresponded to the pressure profile of the shock wave that traveled through the fiber, agreeing quite well with the predictions of the simulation. The wavelength blueshift was about 3.5 nm under a calculated shock pressure in the silica of 320 MPa, induced by a shock pressure of 700 MPa in the host zirconia target. Overall, the 100 μm probe demonstrated superior measurement capabilities to the 1 mm probe, both in time response and localization, as well as better agreement with the simulation. Multiple probes can be applied to provide high resolution mapping of shock phenomena in space and time, thus assisting in establishing the dynamic properties of materials under impact loading.
Spectroscopic investigation of the structure of a pyrrolidinium-based ionic liquid at electrified interfaces
Authors: Kim Jaehyeon , Zhao Fujia , Zhou Shan , Panse Kaustubh S. , Zhang Yingjie
Published: February 2022

The molecular structure of electric double layers (EDLs) at electrode–electrolyte interfaces is crucial for all types of electrochemical processes. Here, we probe the EDL structure of an ionic liquid, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (BMPy-TFSI), using electrochemical shell-isolated nanoparticle-enhanced Raman spectroscopy. We extract the position and intensity of individual peaks corresponding to either intra- or inter-molecular vibrational modes and examine their dependence on the electrode potential. The observed trends suggest that the molecular reconfiguration mechanism is distinct between cations and anions. BMPy+ is found to always adsorb on the Au electrode surface via the pyrrolidinium ring while the alkyl chains strongly change their orientation at different potentials. In contrast, TFSI− is observed to have pronounced position shifts but negligible orientation changes as we sweep the electrode potential. Despite their distinct reconfiguration mechanisms, BMPy+ and TFSI− in the EDL are likely paired together through strong intermolecular interaction.
Enhancement of bandwidth in spin-exchange relaxation-free (SERF) magnetometers with amplitude-modulated light
Authors: Tang Junjian , Liu Ying , Wang Yaxiang , Zhou Binquan , Han Bangcheng , Zhai Yueyang , Liu Gang
Published: February 2022

We demonstrate the bandwidth enhancement of an all-optical spin-exchange relaxation-free (SERF) magnetometer based on amplitude-modulated (AM) light. Alkali metal atoms are modulated directly by the pump beam instead of the modulation field or radio frequency field. The first harmonic demodulation of an AM SERF magnetometer with a modulation intensity of 15 kHz results in a high bandwidth of over 11 kHz with a sensitivity of 20 fT/Hz1/2 at 30 Hz and 60 fT/Hz1/2 at 10 kHz. Meanwhile, the AM SERF magnetometer with DC demodulation presents the same sensitivity as a traditional DC SERF magnetometer (6 fT/Hz1/2 at 30 Hz). The presented technique for modulating the amplitude of the pump beam allows AM SERF magnetometers to enter the domain of high-bandwidth magnetometers and opens the door to many areas that are inaccessible to conventional magnetometers.
Quantum advantage in biometric authentication with single photons
Authors: Kominis Iannis K. , Loulakis Michail
Published: February 2022

It was recently proposed to use the human visual system’s ability to perform efficient photon counting in order to devise a new biometric methodology. The relevant biometric “fingerprint” is represented by the optical losses light suffers along several different paths from the cornea to the retina. The “fingerprint” is accessed by interrogating a subject on perceiving or not weak light flashes, containing few tens of photons, so that the subject’s visual system works at the threshold of perception, at which regime optical losses play a significant role. Here, we show that if, instead of weak laser light pulses, we use quantum light sources, in particular, single-photon sources, we obtain a quantum advantage, which translates into a reduction of the interrogation time required to achieve the desired performance. Besides the particular application on biometrics, our work further demonstrates that quantum light sources can provide deeper insights when studying human vision.
Dynamics of the transition resistance of Al–(Ti, Ni, Mo)–Si type contacts under conditions of non-stationary electrical loads
Authors: Skvortsov Arkadiy A. , Koryachko Marina V. , Kuleshova Svetlana I. , Rybakova Margarita R.
Published: February 2022

This paper analyses the behavioral features of ohmic contacts under the conditions of traditional isothermal annealing. The purpose of this paper is to study the value change of the semiconductor contact resistance when applying electric current pulses of different powers. For the experiments, structures were formed of metal-sublayer-semiconductor wafer Al–(Ti, Ni, Mo)–Si. The quality control of the deposited films was carried out microscopically by the four-probe method. The presented results indicate the solid-phase interaction of components during diffusion annealing Si–Me–Al thin-film systems. This rearrangement of atoms, which occurs with grain-boundary diffusion, significantly affects the electrical and thermal characteristics of the formed contacts. The novelty of the paper is that the optimal parameters of a rectangular current pulse were selected, which made it possible to reduce the value of the transition resistance by 1.6 times.
Silicon and zinc nanoparticles-enriched miscanthus biochar enhanced seed germination, antioxidant defense system, and nutrient status of radish under NaCl stress
Authors: Taqdees Zuhha , Khan Javairia , Khan Waqas-ud-Din , Kausar Salma , Afzaal Muhammad , Akhtar Imran
Published: February 2022

Context Soil salinity mitigation with nanoparticles enriched biochar (Bc) can be a better strategy to resolve the uprising threat against food security. Aim The present study was designed to prepare silicon nanoparticles enriched biochar (Si-En-Bc) and zinc nanoparticles enriched biochar (Zn-En-Bc), which may not only reduced the toxic effects of NaCl stress on initial growth of radish crop but also improved its physiology and defensive mechanism. Method Seeds were germinated in pots with six treatments under normal and NaCl stress, (100 mM NaCl), Zn-En-Bc (1% w/w), and Si-En-Bc (1% w/w). Twenty days old seedlings were harvested and their fresh weight and various germination and biochemical parameters were tested. Key results A significant reduction in malondialdehyde (MDA) and hydrogen peroxide (H2O2) contents was observed with Si-En-Bc + NaCl relative to NaCl stress. It might be due to the significant increase in the antioxidants such as superoxide dismutase (SOD) (42%), ascorbate peroxidase (APX) (38.7%), catalase (CAT) (30.9%) and shoot phenolics (59%) with Si-En-Bc + NaCl over NaCl stress. Application of Zn-En-Bc also caused a maximum increase in root and shoot Zn concentration (76.8 and 54.9%, respectively) under NaCl stress. Conclusions Hence, Si-En-Bc proved to be the best treatment for the radish plant to complete its early growth stage under NaCl stress while Zn-En-Bc not only compensated NaCl stress but also enhanced Zn availability. Implications This study implies that Si-En-Bc or Zn-En-Bc should be applied to the salt affected soil before the crop sowing so seedling can grow under the ameliorative effects of applied amendments. Also, Si-En-Bc or Zn-En-Bc should be tested on a degraded soils at larage scale such as field level.
Climate change adaptation planning for an internationally important wetland, the Muir–Byenup System Ramsar Site in south-west Australia
Authors: Partridge G. , Finlayson C. M.
Published: February 2022

Wetlands, already declining worldwide because of human activities, are at increasing risk from climate change. Despite the Ramsar Convention requirement to maintain the ecological character of wetlands listed as internationally important, there is little guidance for wetland managers to actually do this, let alone plan for and implement adaptation to climate change. This study developed a checklist for planning climate change adaptation and used it to consider adaptation options for the Muir–Byenup System Ramsar site in Australia. Under climate change the site will be subject to future warming and drying, affecting hydrology, bird breeding and feeding, vegetation, peat and threatened species. Fire and wetland acidification are likely to increase. The study found that planning for climate change adaptation had not been widely undertaken for Ramsar sites and, where it had, managers mainly planned information gathering activities and ‘no regrets’ actions rather than innovative or transformative approaches. New management approaches and policy settings that encompass the dynamic nature of wetlands are needed because maintaining wetlands in their current state will be difficult under climate change. The development and sharing of targeted information and training for wetland managers and stakeholders could facilitate a better understanding and uptake of adaptation at wetlands.
An immune-sympathetic neuron communication axis guides adipose tissue browning in cancer-associated cachexia
Authors: Xie Hao , Heier Christoph , Meng Xia , Bakiri Latifa , Pototschnig Isabella , Tang Zhiyuan , Schauer Silvia , Baumgartner Vanessa J. , Grabner Gernot F. , Schabbauer Gernot , Wolinski Heimo , Robertson Graham R. , Hoefler Gerald , Zeng Wenwen , Wagner Erwin F. , Schweiger Martina , Zechner Rudolf
Published: February 2022

Cancer-associated cachexia (CAC) is a hypermetabolic syndrome characterized by unintended weight loss due to the atrophy of adipose tissue and skeletal muscle. A phenotypic switch from white to beige adipocytes, a phenomenon called browning, accelerates CAC by increasing the dissipation of energy as heat. Addressing the mechanisms of white adipose tissue (WAT) browning in CAC, we now show that cachexigenic tumors activate type 2 immunity in cachectic WAT, generating a neuroprotective environment that increases peripheral sympathetic activity. Increased sympathetic activation, in turn, results in increased neuronal catecholamine synthesis and secretion, β-adrenergic activation of adipocytes, and induction of WAT browning. Two genetic mouse models validated this progression of events. 1) Interleukin-4 receptor deficiency impeded the alternative activation of macrophages, reduced sympathetic activity, and restrained WAT browning, and 2) reduced catecholamine synthesis in peripheral dopamine β-hydroxylase (DBH)–deficient mice prevented cancer-induced WAT browning and adipose atrophy. Targeting the intraadipose macrophage-sympathetic neuron cross-talk represents a promising therapeutic approach to ameliorate cachexia in cancer patients.
Inequality in science and the case for a new agenda
Authors: Graves Joseph L. , Kearney Maureen , Barabino Gilda , Malcom Shirley
Published: February 2022

The history of the scientific enterprise demonstrates that it has supported gender, identity, and racial inequity. Further, its institutions have allowed discrimination, harassment, and personal harm of racialized persons and women. This has resulted in a suboptimal and demographically narrow research and innovation system, a concomitant limited lens on research agendas, and less effective knowledge translation between science and society. We argue that, to reverse this situation, the scientific community must reexamine its values and then collectively embark upon a moonshot-level new agenda for equity. This new agenda should be based upon the foundational value that scientific research and technological innovation should be prefaced upon progress toward a better world for all of society and that the process of how we conduct research is just as important as the results of research. Such an agenda will attract individuals who have been historically excluded from participation in science, but we will need to engage in substantial work to overcome the longstanding obstacles to their full participation. We highlight the need to implement this new agenda via a coordinated systems approach, recognizing the mutually reinforcing feedback dynamics among all science system components and aligning our equity efforts across them.
Sharing ‘memories’ on Instagram
Authors: Annabell Taylor
Published: February 2022

This article examines the performance of remembered experience within sharing in-the-moment carried out by young women on Instagram. I propose that the small stories analytical framework provides a way to examine at a micro level sharing of ‘memories’ online by addressing practices of selecting the past, showing and telling the past and interacting with the past in digital traces. For digital memory studies, this moves beyond a focus on affordances and infrastructure transformed memory and the examination of how people engage with memories that have been predefined. The analysis demonstrates how the performance of remembered experience is displayed and positioned across the interplay of past, present and future. Young women’s sharing in-the-moment reconfigures the function and meanings of ‘memories’ beyond the platform’s mobilisation of the term. It is part of how they express feelings and experiences about their unfolding lives.
Encircling exceptional points of Bloch waves: mode conversion and anomalous scattering
Authors: Elbaz Guy , Pick Adi , Moiseyev Nimrod , Shmuel Gal
Published: February 2022

The normal modes of nonconservative systems coalesce at the so-called exceptional points (EPs) of their spectrum. These degeneracy points are the source of unusual phenomena, some of which are accessed by encircling the points in a suitable space. Here, we encircle the EPs of the transfer matrix of a periodic laminate, using a spatial perturbation in its stiffness. We investigate how, collectively, mode conversion in the laminate and the fields it scatters depend on the parameters of the loop. We find that the starting point of the loop has a significant effect on various counterintuitive phenomena: it determines if the laminate acts as a source or a sink of energy; how mode conversion takes place; if the reflectance is greater than one; and if there is spatial asymmetry in the energy flow with respect to the direction of the incident waves. Our findings are relevant for the development of devices for elastic wave manipulation.
Self-assembly of colloidal cube superstructures with critical Casimir attractions
Authors: Kennedy Chris L , Sayasilpi Daphne , Schall Peter , Meijer Janne-Mieke
Published: February 2022

The structure of self-assembled materials is determined by the shape and interactions of the building blocks. Here, we investigate the self-assembly of colloidal ‘superballs’, i.e. cubes with rounded corners, by temperature-tunable critical Casimir forces to obtain insight into the coupling of a cubic shape and short range attractions. The critical Casimir force is a completely reversible and controllable attraction that arises in a near-critical solvent mixture. Using confocal microscopy and particle tracking, we follow the self-assembly dynamics and structural transition in a quasi-2D system. At low attraction, we observe the formation of small clusters with square symmetry. When the attraction is increased, a transition to a rhombic Λ1-lattice is observed. We explain our findings by the change in contact area at faces and corners of the building blocks combined with the increase in attraction strength and range of the critical Casimir force. Our results show that the coupling between the rounded cubic shape and short-range attraction plays a crucial role for the superstructures that form and provide new insights for the active assembly control of micro and nanocubes.
Predicting strain and stress fields in self-sensing nanocomposites using deep learned electrical tomography
Authors: Chen Liang , Hassan Hashim , Tallman Tyler N , Huang Shan-Shan , Smyl Danny
Published: February 2022

Conductive nanocomposites, enabled by their piezoresistivity, have emerged as a new instrument in structural health monitoring. To this end, studies have recently found that electrical resistance tomography (ERT), a non-destructive conductivity imaging technique, can be utilized with piezoresistive nanocomposites to detect and localize damage. Furthermore, by incorporating complementary optimization protocols, the mechanical state of the nanocomposites can also be determined. In many cases, however, such approaches may be associated with high computational cost. To address this, we develop deep learned frameworks using neural networks to directly predict strain and stress distributions—thereby bypassing the need to solve the ERT inverse problem or execute an optimization protocol to assess mechanical state. The feasibility of the learned frameworks is validated using simulated and experimental data considering a carbon nanofiber plate in tension. Results show that the learned frameworks are capable of directly and reliably predicting strain and stress distributions based on ERT voltage measurements.
Isotope removal experiment in JET-ILW in view of T-removal after the 2nd DT campaign at JET
Authors: Wauters T , Matveev D , Douai D , Banks J , Buckingham R , Carvalho I S , de la Cal E , Delabie E , Dittmar T , Gaspar J , Huber A , Jepu I , Karhunen J , Knipe S , Maslov M , Meigs A , Monakhov I , Neverov V S , Noble C , Papadopoulos G , Pawelec E , Romanelli S , Shaw A , Sheikh H , Silburn S , Widdowson A , Abreu P , Aleiferis S , Bernardo J , Borodin D , Brezinsek S , Buermans J , Card P , Carvalho P , Crombe K , Dalley S , Dittrich L , Elsmore C , Groth M , Hacquin S , Henriques R , Huber V , Jacquet P , Jiang X , Jones G , Keeling D , Kinna D , Kirov K , Kovari M , Kowalska-Strzeciwilk E , Kukushkin A B , Kumpulainen H , Litherland-Smith E , Lomas P , Loarer T , Lowry C , Manzanares A , Patel A , Peacock A , Petersson P , Petrella N , Pitts R A , Romazanov J , Rubel M , Siren P , Smart T , Solano E R , Štancar Ž , Varje J , Whitehead A , Wiesen S , Zerbini M , Zlobinski M
Published: February 2022

A sequence of fuel recovery methods was tested in JET, equipped with the ITER-like beryllium main chamber wall and tungsten divertor, to reduce the plasma deuterium concentration to less than 1% in preparation for operation with tritium. This was also a key activity with regard to refining the clean-up strategy to be implemented at the end of the 2nd DT campaign in JET (DTE2) and to assess the tools that are envisaged to mitigate the tritium inventory build-up in ITER. The sequence began with 4 days of main chamber baking at 320 °C, followed by a further 4 days in which Ion Cyclotron Wall Conditioning (ICWC) and Glow Discharge Conditioning (GDC) were applied with hydrogen fuelling, still at 320 °C, followed by more ICWC while the vessel cooled gradually from 320 °C to 225 °C on the 4th day. While baking alone is very efficient at recovering fuel from the main chamber, the ICWC and GDC sessions at 320 °C still removed slightly higher amounts of fuel than found previously in isotopic changeover experiments at 200 °C in JET. Finally, GDC and ICWC are found to have similar removal efficiency per unit of discharge energy. The baking week with ICWC and GDC was followed by plasma discharges to remove deposited fuel from the divertor. Raising the inner divertor strike point up to the uppermost accessible point allowed local heating of the surfaces to at least 800 °C for the duration of this discharge configuration (typically 18 s), according to infra-red thermography measurements. In laboratory thermal desorption measurements, maintaining this temperature level for several minutes depletes thick co-deposit samples of fuel. The fuel removal by 14 diverted plasma discharges is analysed, of which 9, for 160 s in total, with raised inner strike point. The initial D content in these discharges started at the low value of 3%–5%, due to the preceding baking and conditioning sequence, and reduced further to 1%, depending on the applied configuration, thus meeting the experimental target.
Half-cycle and unipolar pulses (Topical Review)
Authors: Arkhipov Rostislav , Arkhipov Mikhail , Pakhomov Anton , Babushkin Ihar , Rosanov Nikolay
Published: February 2022

Unipolar pulses have a nonzero electric pulse area (integral of the electric field strength with respect of time in a given point of space). Due to unidirectional action on charges they can be an efficient tool for ultrafast control of wave packet dynamics in matter, charges acceleration and so one. In this paper, we briefly revise recent advances (including the results obtained by the authors) in optics of extremely-short unipolar half-cycle pulses.
Explaining the lack of power degradation of energy confinement in wide pedestal quiescent H-modes via transport modeling
Authors: Houshmandyar Saeid , Burrell K.H. , Grierson B.A. , McClenaghan J. , Staebler G.M. , Chrystal C. , Halfmoon M.R. , Hatch D.R. , Zeng L. , Austin M.E.
Published: February 2022

Wide pedestal quiescent H (WPQH)-mode is an attractive scenario for future burning plasmas as they operate without ELMs. WPQH is characterized by formation of a wider and higher pedestal (than quiescent H-mode), and broadband fluctuations in the pedestal. Unlike conventional H-modes, where the energy confinement time reduces with increasing heating power, the WPQH plasmas reported in this paper do not show power degradation of the energy confinement. As the injected neutral beam power was increased, reduced core (ρ ⩽ 0.45) transport calculated by transp, as well as increased core temperatures, pressure gradient and diamagnetic
E
×
B
shear rate were observed. The reduction in the heat transport and rapid decrease in the ion temperature gradient scale length suggest the formation of an ion internal transport barrier (ITB) that was accompanied by increased stored energy in the core. Quasilinear turbulent transport modeling using the trapped gyro Landau fluid (tglf) code was used to predict the ITB and its turbulence stability properties. By using profiles and equilibria produced by matching the transp transport fluxes with the tglf transport model within the tgyro transport solver, the energy confinement time captures the experimentally observed insensitivity to the increased P
NBI. Linear stability analysis reveals that drift-wave instabilities in the core are stabilized by
E
×
B
shear, T
i/T
e ratio and Shafranov shift; the latter was found to have the strongest effect on the turbulence suppression at the highest heating level.
Dynamical equivalence classes for Markov jump processes
Authors: Verley Gatien
Published: February 2022

Two different Markov jump processes driven out of equilibrium by constant thermodynamic forces may have identical current fluctuations in the stationary state. The concept of dynamical equivalence classes emerges from this statement as proposed by Andrieux for discrete-time Markov chains on simple graphs. We define dynamical equivalence classes in the context of continuous-time Markov chains on multigraphs using the symmetric part of the rate matrices that define the dynamics. The freedom on the skew-symmetric part is at the core of the freedom inside a dynamical equivalence class. It arises from different splittings of the thermodynamic forces onto the system’s transitions.
Viscous control of minimum uncertainty state in hydrodynamics
Authors: Koide T
Published: February 2022

A minimum uncertainty state for position and momentum of a fluid element is obtained. We consider a general fluid described by the Navier–Stokes–Korteweg (NSK) equation, which reproduces the behaviors of a standard viscous fluid, a fluid with the capillary action and a quantum fluid, with the proper choice of parameters. When the parameters of the NSK equation is adjusted to reproduce Madelung’s hydrodynamic representation of the Schrödinger equation, the uncertainty relation of a fluid element reproduces the Kennard and the Robertson–Schrödinger inequalities in quantum mechanics. The derived minimum uncertainty state is the generalization of the coherent state and its uncertainty is given by a function of the shear viscosity. The viscous uncertainty can be smaller than the inviscid minimum value when the shear viscosity is smaller than a critical value which is similar in magnitude to the Kovtun–Son–Starinets bound. This uncertainty reflects the information of the fluctuating microscopic degrees of freedom in the fluid and will modify the standard hydrodynamic scenario, for example, in heavy-ion collisions.
The influence of the spatial parameters of the laser beam on the track shape in laser metal deposition
Authors: Zavalov Y N , Dubrov A V , Dubrov V D
Published: February 2022

The effect of laser beam focusing parameters on the bead shape in laser metal deposition technology (LMD) is under consideration. The cross-sections of beads formed at different distances between the focus position and the base surface at the plane of the maximum flow density of the gas-powder mixture is obtained. Changing the laser beam’s focusing parameters is shown to vary the shape of the bead and the depth in the LMD technology at constant values of power, scanning speed, and powder consumption.
Gradient estimates for bounded solutions of semilinear elliptic equations and the Allen-Cahn equation on manifolds
Authors: Abolarinwa A. , Edeki S. O. , Oladejo N. K. , Ogundile O.P.
Published: February 2022

This paper aims at deriving apriori bounds on the gradient of positve solutions to a class of semilinear elliptic equation, with applications focusing on establishing a liouville type property for the bounded solutions of the Allen-Cahn equation on a complete noncompact Riemannian manifold with nonnegative Ricci curvature.
A numerical technique for solving infectious disease model
Authors: Magani J.K. , Ogundile O. P. , Edeki S. O.
Published: February 2022

In the medical aspect of life, there are multiple ways of formulating a model that can be used to determine if a disease will become a pandemic or an epidemic. In this research, we discussed how we could use the numerical approach by applying the revised SEQIuIdRF (Susceptible, Exposed, Quarantined, Infected undetected, Infected detected, Recovered, and Failed) model to control or contain an infectious disease (COVID-19) by applying the effective contact rate. MATLAB software was used to solve the SEQIuIdRF model by considering population growth, mortality rate, infection rate, disease-induced death, failed treatment rate, and recovery rate, which gave pictographic diagrams of the increase and decrease of the infectious disease in the community.
SAM approximate solutions of some evolution equations
Authors: Edeki S. O. , Udjor V. O. , Akinlabi G.O. , Achudume C.
Published: February 2022

The Successive Approximation Method (SAM) is introduced in this research to solve the evolution equations. These approximate-analytical solutions of the considered cases are computed with ease. The proposed technique is used directly, without transformation, discretization, linearization, or any restrictive assumptions.
Geometric Analysis and YOLO Algorithm for Automatic Face Detection System in a Security Setting
Authors: Ayo Femi Emmanuel , Mustapha Abiodun Muyideen , Braimah Joachim Ayodeji , Aina Daniel Ayodele
Published: February 2022

Face detection is a computer technology that determines the location and size of the human face in an arbitrary digital image employed for authentication. Face recognition technology plays a vital role in network security, video compression, content indexing, and retrieval since "humans" are the focal point of many videos. Face recognition-based network access control makes it almost difficult for hackers to obtain a user’s "password" and improves user-friendliness in human-computer interaction. In this paper, an automatic face detection system that accurately detects human faces and ignores any other object that is not a human face using geometric analysis and the you-only-look-once (YOLO) algorithm is introduced. The system is able to predict the ages and genders of the faces detected. It also detects the facial landmarks of the faces and indicates the emotions of the faces detected. A sample of four faces is considered for testing the system; thus, accurately detecting gender and emotion but not age correctly. In all, the evaluation shows about 80% accuracy. With the results got, the system can support security and analytics. It can be used to get analytics in an event with a lot of attendees and can also be used to get a facial mapping of someone involved in a crime scene for security purposes.
Application of solar energy to fruit and vegetable refrigerator in aiding the impoverished during the Covid-19 pandemic
Authors: Nguyen Thanh Tung , Hoa Dinh Thi , Truc Ho Ngoc Thanh , Phu Huynh Minh
Published: February 2022

Solar energy has now been applied to provide energy in many different fields around the world. In Vietnam, many solar energy projects are being implemented. In this transdisciplinarity research, research team and local stakeholders participate in designing a solar application to power a fruit and vegetable refrigerator located at Cu lao Rua, Thanh Hoi commune, Tan Uyen Town, Binh Duong province, Vietnam for the poor worker living in the disadvantaged localities with difficulties due to the impact of the Covid-19 pandemic. This is considered a community development project with the use of renewable energy, contributing to environmental protection of the new rural commune.
Mechanical and Microstructural Properties of Hybrid Bio-Composites using Microwaved Coconut Fibre and Rice Husk
Authors: Johar M F , Ariff T F
Published: February 2022

The outstanding mechanical and environmental qualities of hybrid bio-composites have made them popular. The drying procedure to remove the moisture before manufacture, on the other hand, can take a long period. By modifying the macromolecular structure considerably faster, hybrid bio-composites with additional physical treatment utilising microwave energy could improve their mechanical capabilities. Fillers of 80:15:5, 90:5:5, and 98:1:1 coconut fibre and rice husk were combined with poly-lactic acid (PLA) utilising melt-mixing and hot press techniques. The fillers were dried in a conventional oven at 60°C for 24 hours and in a microwave oven at 2.45 GHz for 3 minutes. When tensile strength was tested, it was discovered that oven-treated fibres with a 98:1:1 composition had a higher tensile strength (63 MPa) than microwave-treated fibres (58 MPa). Microwave-treated fibres, on the other hand, had a higher flexural strength (69 MPa) than those treated in a normal oven (60 MPa). Furthermore, when compared to plain PLA, microwave energy enhanced the toughness of the bio-composites by at least 4%. For the 80:15:5 composition, microwave-treated fibres had a lower water absorptivity (2%) than conventionally treated fibres, which had a water absorptivity of 5%. SEM images confirmed the presence of agglutination and voids with higher fibre content, resulting in poor adhesion and low tensile and flexural strength.
Implementation of Two-step Hybrid Block Adams Moulton Solution Methods for First Order Delay Differential Equations
Authors: Chibuisi C. , Osu B. O. , Edeki S. O. , Akinlabi G. O. , Olunkwa C. , Ogundile O. P.
Published: February 2022

In this paper, Hybrid Block Adams Moulton Methods for step number k = 2 merged with two and three off-grid points were obtained and implemented in solving first order delay differential equations without the use of interpolation condition in evaluating the delay expression. The discrete schemes of these off-grid hybrid block methods were assessed through the continuous development of the linear multistep collocation method using a matrix conversion formula. The results obtained after the implementation of the proposed method in for numerical experiment of some first-order DDEs, the BHAMM2 schemes performed better and faster in satisfying the axioms for convergence and region of absolute stability than the BHAMM3 schemes at fixed step size z when examined with other existing methods.
An Explicit Note on the Existence Theorem of Optimal Control Problem
Authors: Abidemi Afeez , Olaniyi Samson , Adepoju Okunloye A.
Published: February 2022

This short note presents an explicit step-by-step proof of the existence theorem of an optimal control problem applied to a deterministic model for a vector-borne disease.
Laplace decomposition method for series solutions of systems of linear partial differential models
Authors: Engworo G. P. , Ogunniyi P. O. , Edeki S. O.
Published: February 2022

Most of the real-life problems experienced in the industry these days cannot be expressed as a single differential equation but as a system of differential equations. Such structures of linear partial differential models are considered in this work with the aid of the Laplace Adomian decomposition method (LADM) in terms of solutions. Various examples are taken into consideration. The results are easily obtained, are in good agreement when compared to their exact forms. In addition, the proposed method seems effective and efficient; the solutions are graphically presented.
Solar energy research for the design and manufacturing of oxygen aerator model for shrimp farming
Authors: Phu Huynh Minh , Nguyen Thanh Tung
Published: February 2022

This project refers to the research, design, and manufacturing of an oxygen aerator prototype for shrimp farming using solar energy. An offline solar system is calculated, designed to drive a 24VDC motor that rotates the propellers to generate oxygen in shrimp ponds. This system is researched for shrimp farming areas without electricity in order to expand shrimp farming capacity for coastal areas. The system can connect to the phone via Bluetooth to transmit the model’s parameters to the user interface. An app that connects the phone to the oxygen aerator is also designed to control and monitor data. Solar-powered oxygen aerators for shrimp ponds can help farmers save 2 to 3 times the cost compared to gas and oil-powered oxygen aerators.
Analysis of Seasonal Precipitation Rate in Nigeria Using Dataset from Tropical Rainfall Measuring Mission
Authors: Arijaje T. E. , Omotosho T. V. , Akinwumi S. A. , Ometan O. O. , Fashade O. O.
Published: February 2022

The study aimed to analyze the seasonal precipitation rate using dataset retrieved from TRMM over Nigeria. The Seasons evaluated are December to February (DJF), March to May (MAM), June to August (JJA) and September to October (SON) using ten years (December 2009-November 2019) data acquired from TRMM data base. The result shows that, the precipitation rate differs and these ranges from light precipitation from the northern regions to heavy precipitation in the southern regions. For the DJF season, the northern regions experience little or no precipitation especially during the dry season. Meanwhile, during the MAM, JJA and SON seasons, the northern regions experiences light to moderate (0 ≤ R < 5 mm/h) precipitation rate according to World Meteorological Organization (WMO) while the southern regions experience moderate to heavy (0.1 ≤ R ≥ 0.5 mm/h) precipitation rate with its peak at MAM and SON seasons which correspond to the wet months/season and early dry season. It follows that the result obtained from this work is in agreement with the WMO. The result from this work will provide an insight on precipitation event which in turn, will help in decision making on various ways of adaptation and also, planning of outdoors events such as agricultural activities (food securities), sport activities and also in the telecommunication and aviation as increase in the rate precipitation increases the attenuation on communication link.
Remarks on Analytical Solutions of a Non-Homogeneous Gas Dynamic Model via Successive Approximation Method
Authors: Edeki S.O. , Adeyeye F.J. , Akinlabi G.O. , Udjor V.O.
Published: February 2022

The Successive Approximation Method (SAM) is introduced in this research to solve the non-homogeneous Gas Dynamic Equation (GDE). This GDE’s analytical solution is expressed via the SAM, in series form, with readily computed components. The proposed technique is used directly, without transformation, discretization, linearization, or any restrictive assumptions.
Unsupervised Kernel-Induced Fuzzy Possibilistic C-Means Technique in Investigating Real-World Data
Authors: Devi R
Published: February 2022

The goal of this study is to break down a large dataset into meaningful groupings. Due to the vast dimension and significant resemblance seen among data, exploring divided clusters in real-world datasets is the most difficult assignment. As a result, this work proposes a fuzzy set-based unsupervised effective clustering technique that includes possibilistic memberships, and fuzzy membership degrees into the membership, weighted Cauchy kernel-based similarity measure and center equations. The empirical findings demonstrate the feasibility of the proposed effective clustering technique.
Stability Analysis of an SIR Infectious Disease Model
Authors: Ezekiel D , Iyase S A , Anake T A
Published: February 2022

The paper investigates the stability of the SIR mathematical model of transmission of an infectious disease with delay. First, the study investigates local stability of the positive steady state of an infectious disease model by analyzing the linearised system where more general stability criteria with delay and model parameters are obtained. Secondly, the study shows that the model exhibits Hopf bifurcation on choosing the delay as a bifurcation parameter. Conditions for existence of qualitative behaviour for positive steady state are identified. Finally, numerical simulation of results and biological interpretations were verified using MATLAB software for the delay model. The study supplements theoretical improvement to earlier results obtained in the literature.