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1

WEBB, G. M., A. R. ZAKHARIAN, M. BRIO, and G. P. ZANK. "Parametric instabilities and wave coupling in Alfvén simple waves." Journal of Plasma Physics 66, no. 3 (2001): 167–212. http://dx.doi.org/10.1017/s0022377801001283.

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A wave coupling formalism for magnetohydrodynamic (MHD) waves in a non-uniform background flow is used to study parametric instabilities of the large-amplitude, circularly polarized, simple plane Alfvén wave in one Cartesian space dimension. The large-amplitude Alfvén wave (the pump wave) is regarded as the background flow, and the seven small-amplitude MHD waves (the backward and forward fast and slow magnetoacoustic waves, the backward and forward Alfvén waves, and the entropy wave) interact with the pump wave via wave coupling coefficients that depend on the gradients and time dependence of the background flow. The dispersion equation for the waves D(k,ω) = 0 obtained from the wave coupling equations reduces to that obtained by previous authors. The general solution of the initial value problem for the waves is obtained by Fourier and Laplace transforms. The dispersion function D(k,ω) is a fifth-order polynomial in both the wavenumber k and the frequency ω. The regions of instability and the neutral stability curves are determined. Instabilities that arise from solving the dispersion equation D(k,ω) = 0, both in the form ω = ω(k), where k is real, and in the form k = k(ω), where ω is real, are investigated. The instabilities depend parametrically on the pump wave amplitude and on the plasma beta. The wave interaction equations are also studied from the perspective of a single master wave equation, with multiple wave modes, and with a source term due to the entropy wave. The wave hierarchies for short- and long-wavelength waves of the master wave equation are used to discuss wave stability. Expanding the dispersion equation for the different long-wavelength eigenmodes about k = 0 yields either the linearized Korteweg–deVries equation or the Schrödinger equation as the generic wave equation at long-wavelengths. The corresponding short-wavelength wave equations are also obtained. Initial value problems for the wave interaction equations are investigated. An inspection of the double-root solutions of the dispersion equation for k, satisfying the equations D(k,ω) = 0 and ∂D(k,ω) = ∂k = 0 and pinch point analysis shows that the solutions of the wave interaction equations for hump or pulse-like initial data develop an absolute instability. Fourier solutions and asymptotic analysis are used to study the absolute instability.
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2

Novitskaya, Alla Aleksandrovna, Natalia Vladimirovna Lapenkova, and Alexander Sergeevich Linnikov. "Research of China-Us K-wave based decision making." LAPLAGE EM REVISTA 7, Extra-C (2021): 78–86. http://dx.doi.org/10.24115/s2446-622020217extra-c989p.78-86.

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Most prominent works on the subject, including k-wave theory-based research, do not elaborate on the topic of interconnectivity between economy and research on a microeconomic scale, instead of focusing on general innovation theory and macroeconomic stimuli. Present paper aims to discover k-wave theory-based decision making and potential explanation in R&D standoff between the United States, leader of fifth technological paradigm, and China – emerging leader of sixth technological paradigm. Overall conducted research shows fundamental divergence and a variety of interpretations within the framework of the k-wave theory itself, the proposed change in recourse flow stands true which in turn signifies the importance of k-wave theory in the modern decision-making process.
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3

Gallerano, Francesco. "Numerical Modelling of Wave Fields and Currents in Coastal Area." Water 12, no. 6 (2020): 1582. http://dx.doi.org/10.3390/w12061582.

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The design and management of coastal engineering, like harbors and coastal defense structures, requires the simulation of hydrodynamic phenomena. This special issue collects five original papers that address state of the art numerical simulations of wave fields and wave-induced velocity fields in coastal areas. The first paper proposes a turbulence model for wave breaking simulation, which is expressed in terms of turbulent kinetic energy and dissipation rate of turbulent kinetic energy (k − ε); the proposed turbulence model is a modification of the standard k − ε turbulence models. The second paper investigates modalities by which wind interacts with wave motion, modifying the wave propagation dynamic. The third paper proposes a study on waves overtopping over coastal barriers. The fourth paper details the numerical simulation of a tsunami wave that propagates over an artificial reservoir, caused by a landslide that creates a solid mass to detach from the slopes and to slide into the reservoir. The fifth paper examines an application case concerning Cetraro harbor (Italy), which is carried out using three-dimensional numerical simulations of wave motion.
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4

ZHANG, WEIGUO, YAN ZHAO, GANG LIU, and TONGKE NING. "PERIODIC WAVE SOLUTIONS FOR POCHHAMMER–CHREE EQUATION WITH FIVE ORDER NONLINEAR TERM AND THEIR RELATIONSHIP WITH SOLITARY WAVE SOLUTIONS." International Journal of Modern Physics B 24, no. 19 (2010): 3769–83. http://dx.doi.org/10.1142/s0217979210056268.

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In this paper, periodic wave solutions for Pochhammer–Chree equation (PC-equation) with fifth order nonlinear term and their relationship with solitary wave solutions are studied. By designing innovative structure of solution, sixteen bounded periodic wave solutions in fractional form of Jacobi elliptic function (JEF) for PC-equation are given. Furthermore, global phase figure in the plane of the traveling solution for the PC-equation are obtained through dynamic systematic method, we indicate the region in the phase where the given sixteen solutions for PC-equation belong to. We find that two couples of these solutions change into two bell profile solitary wave solutions as k → 1 and four solutions change into four periodic wave solutions in fractional form of cosine function as k → 0. Finally, four figures are shown to describe the evolvement from periodic wave solutions to bell profile solitary wave solutions as k → 1.
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5

Sedletsky, Yu V. "A Fifth-Order Nonlinear Schrödinger Equation for Waves on the Surface of Finite-Depth Fluid." Ukrainian Journal of Physics 66, no. 1 (2021): 41. http://dx.doi.org/10.15407/ujpe66.1.41.

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We derive a high-order nonlinear Schr¨odinger equation with fifth-order nonlinearity for the envelope of waves on the surface of a finite-depth irrotational, inviscid, and incompressible fluid over the flat bottom. This equation includes the fourth-order dispersion, cubic-quintic nonlinearity, and cubic nonlinear dispersion effects. The coefficients of this equation are given as functions of one dimensionless parameter kℎ, where k is the carrier wave number, and ℎ is the undisturbed fluid depth. These coefficients stay bounded in the infinite-depth limit.
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6

Shi, Ru Chao, Sheng Li Xu, and Ya Jun Zhang. "Simulation of Water Droplet Merging under Shock Wave Using Real Ghost Fluid Method." Applied Mechanics and Materials 444-445 (October 2013): 628–32. http://dx.doi.org/10.4028/www.scientific.net/amm.444-445.628.

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This paper presents a 3D numerical simulation of water droplets merging under a given shock wave. We couple interpolation method to RGFM (Real Ghost Fluid Method) to improve the numerical accuracy of RGFM. The flow states of air-water interface are calculated by ARPS (approximate Riemann problem solver). Flow field is solved by Euler equation with fifth-order WENO spatial discretization and fourth-order R-K (Runge-Kutta) time discretization. We also employ fifth-order HJ-WENO to discretize level set equation to keep track of gas-liquid interface. Numerical results demonstrate that droplets shape has little change before merging and the merged droplet gradually becomes umbrella-shaped under the given shock wave. We verify that combination of RGFM with interpolation method has the property of reducing numerical error by comparing to the results without employment of interpolation method.
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7

Wang, Jianyong, and Yuanhua Chai. "New patterns of localized excitations in (2+1)-dimensions: The fifth-order asymmetric Nizhnik–Novikov–Veselov equation." Communications in Theoretical Physics 76, no. 8 (2024): 085002. http://dx.doi.org/10.1088/1572-9494/ad531b.

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Abstract By applying the mastersymmetry of degree one to the time-independent symmetry K 1, the fifth-order asymmetric Nizhnik–Novikov–Veselov system is derived. The variable separation solution is obtained by using the truncated Painlevé expansion with a special seed solution. New patterns of localized excitations, such as dromioff, instanton moving on a curved line, and tempo-spatial breather, are constructed. Additionally, fission or fusion solitary wave solutions are presented, graphically illustrated by several interesting examples.
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8

Chen, Xi, Mei Hong, Shiqi Wu, Kefeng Liu, and Kefeng Mao. "Design of Wave Glider Optimal Parameters Suitable for the Northwest Pacific Ocean, the North Indian Ocean, and the South China Sea." Journal of Marine Science and Engineering 9, no. 4 (2021): 408. http://dx.doi.org/10.3390/jmse9040408.

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To study the optimal design of Wave Glider parameters in the wave environment of the Northwest Pacific Ocean, the North Indian Ocean, and the South China Sea, the average velocity of a Wave Glider was taken as the evaluation criterion. Wave reanalysis data from ERA5 were used to classify the mean wave height and period into five types by the K-means clustering method. In addition, a dynamic model was used to simulate the influence of umbilical length, airfoil, and maximum limited angle on the velocity of the Wave Glider under the five types of wave element. The force of the wings was simulated using FLUENT as the model input. The simulation results show that (1) 7 m is the most suitable umbilical length; (2) a smaller relative thickness should be selected in perfect conditions; and (3) for the first type of wave element, 15° is the best choice for the maximum limited angle, and 20° is preferred for the second, third, and fourth types, while 25° is preferred for the fifth type.
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9

Dusek, Michal, Gervais Chapuis, Mathias Meyer, and Vaclav Petricek. "Sodium carbonate revisited." Acta Crystallographica Section B Structural Science 59, no. 3 (2003): 337–52. http://dx.doi.org/10.1107/s0108768103009017.

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We present the structure of anhydrous sodium carbonate at room temperature (phase γ) and 110 K (phase δ) based on single-crystal X-ray diffraction data. The incommensurate phase γ was determined almost 30 years ago in the harmonic approximation using one modulation wave and first-order satellites. In our work we use satellites up to fifth order and additional harmonic waves to model the anharmonic features of the structure. The commensurate phase δ is presented for the first time. Using the superspace approach, both phases are compared in order to find common trends in the whole range of the sodium carbonate phases. We present arguments supporting the hypothesis that the driving force of the phase transitions may originate in the unsaturated bonding potential of one of the Na ions.
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10

Alanazi, Meshari D. "A Review of Dielectric Resonator Antenna at Mm-Wave Band." Eng 4, no. 1 (2023): 843–56. http://dx.doi.org/10.3390/eng4010051.

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This paper is a comprehensive review of the recent literature studies on the developments and applications of millimeter-wave (mm-wave) dielectric resonator antennas (DRAs). Different designs and techniques for linear and circular polarized DRAs are discussed thoroughly. In addition, array and multiple-input multiple-output (MIMO) DRAs operating in the K, Ka, and V bands are illustrated. These applications are highly advantageous on many levels, resulting in the improved performance of the DRA in terms of obtaining a higher gain, lower losses, a higher efficiency, and a lower profile. This work reviews the fundamental research trends in antennas to meet the demands of fifth-generation (5G) communications and beyond. The reviewed studies are scholarly sources which contain measurement-based results. This paper concludes by highlighting the limitations of the studies and the implications for future research.
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11

Barratt, Dylan, Ton Stefan van den Bremer, and Thomas Alan Adcock Adcock. "MNLS simulations of surface wave groups with directional spreading in deep and finite depth waters." Journal of Ocean Engineering and Marine Energy 7, no. 3 (2021): 261–75. http://dx.doi.org/10.1007/s40722-021-00201-2.

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AbstractWe simulate focusing surface gravity wave groups with directional spreading using the modified nonlinear Schrödinger (MNLS) equation and compare the results with a fully-nonlinear potential flow code, OceanWave3D. We alter the direction and characteristic wavenumber of the MNLS carrier wave, to assess the impact on the simulation results. Both a truncated (fifth-order) and exact version of the linear dispersion operator are used for the MNLS equation. The wave groups are based on the theory of quasi-determinism and a narrow-banded Gaussian spectrum. We find that the truncated and exact dispersion operators both perform well if: (1) the direction of the carrier wave aligns with the direction of wave group propagation; (2) the characteristic wavenumber of the carrier wave coincides with the initial spectral peak. However, the MNLS simulations based on the exact linear dispersion operator perform significantly better if the direction of the carrier wave does not align with the wave group direction or if the characteristic wavenumber does not coincide with the initial spectral peak. We also perform finite-depth simulations with the MNLS equation for dimensionless depths ($$k_{\text {p}}d$$ k p d ) between 1.36 and 5.59, incorporating depth into the boundary conditions as well as the dispersion operator, and compare the results with those of fully-nonlinear potential flow code to assess the finite-depth limitations of the MNLS.
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12

Zhang, Tongzheng, Zhiqiang Liu, Junbo Zhang, Xing Su, Junlin Chen, and Rong Wan. "Numerical Study of the Hydrodynamic Response of Biodegradable Drifting Fish Aggregating Devices in Regular Waves." Fishes 9, no. 4 (2024): 112. http://dx.doi.org/10.3390/fishes9040112.

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Fish-aggregating devices play a significant role in tuna purse fisheries. The severe marine environment and the large number of non-biodegradable fish-aggregating devices impact structural safety and cause marine litter. Therefore, hydrodynamic performance and the use of biodegradable materials are crucial issues for ensuring the sustainability of fish-aggregating devices. In this study, a type of virtual biodegradable drifting fish-aggregating device (Bio-DFAD) was designed. Numerical simulations were conducted to investigate the motion responses and relative velocities of Bio-DFADs in regular waves (first- and fifth-order waves). The numerical model was applied based on unsteady Reynolds-averaged Navier–Stokes equations with the realizable k–ε model. For different scenarios of modeling, various conditions were modeled, including the relative length, wave steepness, and diameter of the balsa wood, to analyze their effects on the hydrodynamic response of the Bio-DFADs. The results indicated that the increased relative length, wave steepness, and diameter of balsa wood had a significant influence on the motion response amplitude operators (RAOs) and relative velocity of Bio-DFADs. The results suggested that a relative length (LF/B = 1.5) and smaller diameter (DF = 30 mm) were recommended for fewer motion responses and relative velocity. The obtained results provide insight for practical engineering applications of the hydrodynamic design of Bio-DFADs.
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13

Al-Falahy, Naser, Mohammed AlMahamdy, and Ali M. Mahmood. "Performance analysis of millimeter wave 5G networks for outdoor environment: propagation perspectives." Indonesian Journal of Electrical Engineering and Computer Science 20, no. 1 (2020): 214. http://dx.doi.org/10.11591/ijeecs.v20.i1.pp214-221.

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<span>To cope with the massive growth in global mobile data traffic for 2020 and beyond, the Fifth Generation (5G) system is required to be developed as the current 4G system is expected to fall short behind the provision of such growth. 5G systems is anticipated to use millimeter wave (mm-wave) frequency bands (20 to 90) GHz, due to the availability of wide chunk of unexploited bandwidth. This is revolutionary step to use these bands because of their very different propagation conditions, atmospheric absorption and hardware constraints. However, such challenges could be compensated by means of beamforming/beamsteering and larger antenna array. In this paper, a comparative study aided with ray-tracing simulation has been performed to assess the feasibility of mm-wave in 5G system. Propagation characteristics of the 28GHz and 73 GHz bands have been studied and compared in a street canyon outdoor environment to simulate 5G outdoor mobile access. Simulation results were shown along with their comparison for both of the aforementioned frequencies. The results of propagation comparison have been reported in terms of path loss, k-factor, delay spread and received power for both 28 and 73 GHz bands.</span>
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14

Naser, Al-Falahy, AlMahamdy Mohammed, and M. Mahmood Ali. "Performance analysis of millimeter wave 5G networks for outdoor environment: propagation perspectives." Indonesian Journal of Electrical Engineering and Computer Science 20, no. 1 (2020): 214–21. https://doi.org/10.11591/ijeecs.v20.i1.pp214-221.

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To cope with the massive growth in global mobile data traffic for 2020 and beyond, the Fifth Generation (5G) system is required to be developed as the current 4G system is expected to fall short behind the provision of such growth. 5G systems is anticipated to use millimeter wave (mm-wave) frequency bands (20 to 90) GHz, due to the availability of wide chunk of unexploited bandwidth. This is revolutionary step to use these bands because of their very different propagation conditions, atmospheric absorption and hardware constraints. However, such challenges could be compensated by means of beamforming/beamsteering and larger antenna array. In this paper, a comparative study aided with ray-tracing simulation has been performed to assess the feasibility of mm-wave in 5G system. Propagation characteristics of the 28GHz and 73 GHz bands have been studied and compared in a street canyon outdoor environment to simulate 5G outdoor mobile access. Simulation results were shown along with their comparison for both of the aforementioned frequencies. The results of propagation comparison have been reported in terms of path loss, k-factor, delay spread and received power for both 28 and 73 GHz bands.
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15

Iele, Benedetta, Federica Palleschi, Giovanni Cannata, and Francesco Gallerano. "A New Turbulence Model for Breaking Wave Simulations." Water 14, no. 13 (2022): 2050. http://dx.doi.org/10.3390/w14132050.

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In this paper, the hydrodynamic and free surface elevation fields in breaking waves are simulated by solving the integral and contravariant forms of the three-dimensional Navier–Stokes equations that are expressed in a generalized time-dependent curvilinear coordinate system, in which the vertical coordinate moves by following the free surface. A new k−l turbulence model in contravariant form is proposed; in this model, the mixing length, l, is defined as a function of the maximum water surface elevation variation. A new original numerical scheme is proposed. The main element of originality of the numerical scheme consists of the proposal of a new fifth-order reconstruction technique for the point values of the conserved variables on the cell face. This technique, named in the paper as WTENO, allows the choice procedure of the reconstruction polynomials for the point values to be modified in a dynamic way.
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16

Wang, Yunhao, Jiabao Chen, Yan Wang, Yuhang Zeng, and Shitang Ke. "A WENO-Based Upwind Rotated Lattice Boltzmann Flux Solver with Lower Numerical Dissipation for Simulating Compressible Flows with Contact Discontinuities and Strong Shock Waves." Applied Sciences 14, no. 23 (2024): 11450. https://doi.org/10.3390/app142311450.

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This paper presents a WENO-based upwind rotated lattice Boltzmann flux solver (WENO-URLBFS) in the finite difference framework for simulating compressible flows with contact discontinuities and strong shock waves. In the method, the original rotating lattice Boltzmann flux solver is improved by applying the theoretical solution of the Euler equation in the tangential direction of the cell interface to reconstruct the tangential flux so that the numerical dissipation can be reduced. The fluxes at each interface are evaluated using a weighted summation of lattice Boltzmann solutions in two local perpendicular directions decomposed from the direction vector so that the stability performance can be improved. To achieve high-order accuracy, both fifth and seventh-order WENO reconstructions of the flow variables in the characteristic spaces are carried out. The order accuracy of the WENO-URLBFS is evaluated and compared with the traditional Lax–Friedrichs scheme, Roe scheme, and the LBFS by simulating the advection of the density disturbance problem. It is shown that the fifth and seventh-order accuracy can be achieved by all considered flux-evaluation schemes, and the present WENO-URLBFS has the lowest numerical dissipation. The performance of the WENO-URLBFS is further examined by simulating several 1D and 2D examples, including shock tube problems, Shu–Osher problems, blast wave problems, double Mach reflections, 2D Riemann problems, K-H instability problems, and High Mach number astrophysical jets. Good agreements with published data have been achieved quantitatively. Moreover, complex flow structures, including shock waves and contact discontinuities, are successfully captured. The present WENO-URLBFS scheme seems to present an effective numerical tool with high-order accuracy, lower numerical dissipation, and strong robustness for simulating challenging compressible flow problems.
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17

Santos, Mário João, and Jaime Batista Santos. "Ultrasonic Scattering Attenuation in Nodular Cast Iron: Experimental and Simulation Studies." Strojniški vestnik – Journal of Mechanical Engineering 67, no. 5 (2021): 245–55. http://dx.doi.org/10.5545/sv-jme.2020.7078.

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This work evaluates the ultrasonic scattering attenuation of structures with complex scatterer distributions via experimental and simulation studies. The proposed approach uses experimental attenuation knowledge to infer the scatterer size and its concentration in the studied structures, which are important for the effective construction of simulated models. The MATLAB k-Wave toolbox has been used to implement the simulator. Several cast-iron samples have been used to demonstrate the importance of simulation in the characterization of such structures. First, the scattering attenuation was evaluated using the Truell and Papadakis models, and then the results were compared with experimental ones. Emphasis was given to the Papadakis approach because it takes into account the scatterer size distribution. It is demonstrated that both analytical models provide results that are far from the experimental ones. The developed simulator for the studied samples led to a predictive model, in which the attenuation was proportional to the fifth power of the scatterer size, and the corresponding formulation is close to the one proposed by the analytical models.
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18

Nieroda, Paweł, Juliusz Leszczyński, Krzysztof Kapera, et al. "Thermoelectric Properties of Cu2S Doped with P, As, Sb and Bi—Theoretical and Experimental Studies." Materials 17, no. 22 (2024): 5440. http://dx.doi.org/10.3390/ma17225440.

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The aim of this work was to investigate the possibility of doping copper sulfide Cu2S with selected fifth-group elements, potentially having a positive effect on the thermoelectric properties of the resulting materials. For the selected model structures, theoretical calculations and an analysis of the electronic structure and changes in the enthalpy of formation due to doping were performed using the WIEN2k package employing the Full-Potential Linearized Augmented Plane Wave (FP-LAPW) method within density functional theory (DFT) formalism. Polycrystalline materials with the nominal composition of Cu32S15X1 (X = P, As, Sb, Bi) were synthesized in quartz ampoules, then sintered using the spark plasma sintering (SPS) technique and “SPS melting” method. The chemical and phase compositions of the obtained sinters were studied by X-Ray diffraction (XRD) and scanning electron microscopy (SEM). Additionally, investigations of thermoelectric properties, i.e., electrical conductivity, Seebeck coefficient and thermal conductivity in the temperature range 300–920 K, were performed. The results of this study indicate that only phosphorus is successfully incorporated into the Cu₂S structure.
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19

Uko, Mfonobong, Sunday Ekpo, Sunday Enahoro, Fanuel Elias, Rahul Unnikrishnan, and Yasir Al-Yasir. "Highly Adaptive Reconfigurable Receiver Front-End for 5G and Satellite Applications." Technologies 13, no. 4 (2025): 124. https://doi.org/10.3390/technologies13040124.

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The deployment of fifth-generation (5G) and beyond-5G wireless communication systems necessitates advanced transceiver architectures to support high data rates, spectrum efficiency, and energy-efficient designs. This paper presents a highly adaptive reconfigurable receiver front-end (HARRF) designed for 5G and satellite applications, integrating a switchable low noise amplifier (LNA) and a single pole double throw (SPDT) switch. The HARRF architecture supports both X-band (8–12 GHz) and K/Ka-band (23–28 GHz) operations, enabling seamless adaptation between radar, satellite communication, and millimeter-wave (mmWave) 5G applications. The proposed receiver front-end employs a 0.15 μm pseudomorphic high electron mobility transistor (pHEMT) process, optimised through a three-stage cascaded LNA topology. A switched-tuned matching network is utilised to achieve reconfigurability between X-band and K/Ka-band. Performance evaluations indicate that the X-band LNA achieves a gain of 23–27 dB with a noise figure below 7 dB, whereas the K/Ka-band LNA provides 23–27 dB gain with a noise figure ranging from 2.3–2.6 dB. The SPDT switch exhibits low insertion loss and high isolation, ensuring minimal signal degradation across operational bands. Network analysis and scattering parameter extractions were conducted using advanced design system (ADS) simulations, demonstrating superior return loss, power efficiency, and impedance matching. Comparative analysis with state-of-the-art designs shows that the proposed HARRF outperforms existing solutions in terms of reconfigurability, stability, and wideband operation. The results validate the feasibility of the proposed reconfigurable RF front-end in enabling efficient spectrum utilisation and energy-efficient transceiver systems for next-generation communication networks.
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Al-Saman, Ahmed, Marshed Mohamed, and Michael Cheffena. "Radio Propagation Measurements in the Indoor Stairwell Environment at 3.5 and 28 GHz for 5G Wireless Networks." International Journal of Antennas and Propagation 2020 (December 27, 2020): 1–10. http://dx.doi.org/10.1155/2020/6634050.

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To cover the high demand for wireless data services for different applications in the wireless networks, different frequency bands below 6 GHz and in millimeter-wave (mm-Wave) above 24 GHz are proposed for the fifth generation (5G) of communication. The communication network is supposed to handle, among others, indoor traffic in normal situations as well as during emergencies. The stairway is one of those areas which has less network traffic during normal conditions but increases significantly during emergencies. This paper presents the radio propagation in an indoor stairway environment based on wideband measurements in the line of sight (LOS) at two candidate frequencies for 5G wireless networks, namely, 3.5 GHz and 28 GHz. The path loss, root mean square (RMS) delay spread, K-factor results, and analysis are provided. The close-in free-space reference distance (CI), floating intercept (FI), and the close-in free-space reference distance with frequency weighting (CIF) path loss models are provided. The channel parameters such as the number of clusters, the ray and cluster arrival rates, and the ray and cluster decay factors are also obtained for both frequencies. The findings of the path loss show that the CI, FI, and CIF models fit the measured data well in both frequencies with the path loss exponent identical to the free-space path loss. Based on clustering results, it is found that the cluster decay rates are identical at both bands. The results from this and previous measurements indicate that at least one access point is required for every two sections of the stairway to support good coverage along the stairwell area in 5G wireless networks. Moreover, for 5G systems utilizing mm-Wave frequency bands, one access point for each stair section might be necessary for increased reliability of the 5G network in stairwell environments.
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Muttair, Karrar Shakir, Oras Ahmed Shareef, Hazeem Baqir Taher, and Faiz Arith. "A New Geometry of Multi-band MIMO Antenna for 5G and 6G Systems." Journal of Techniques 6, no. 4 (2024): 48–56. https://doi.org/10.51173/jt.v6i4.2596.

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The demand for high-efficiency, small-sized ultrawide-band (UWB) antennas has risen due to the need for fast wireless communication systems. In this manuscript, we propose a novel geometry for a 4-port multi-in multi-out (MIMO) antenna with an L-shaped structure that solves the limitations of current designs in UWB applications. The dimensions and thickness of an antenna design are 18×18×1.5875 mm. It operates in multiple bands, such as Ku, K, and millimeter wave (mmWave) spectrum ranging from 17 to 100 GHz. This feature is ideal for small fifth-generation (5G) and sixth-generation (6G) wireless communication devices. We used two separate ground strips at the bottom to minimize interference in the MIMO element design and enhance antenna performance. The antenna performed exceptionally well in all measured parameters. The reflection coefficient (RC) was less than -10 dB, the mutual coupling (MC) coefficient reached -62.4 dB, and the radiation antenna efficiency ranged between 82% and 94%. It achieved the highest gain of 13 dBi at 87 GHz. In addition, the envelope correlation coefficient (ECC) is < 0.02, and the diversity gain (DG) ranges between 9.9 and 10 dB. This antenna surpasses all others in every parameter when compared to proposals by different researchers. This makes it a superior choice for modern wireless devices catering to 5G and 6G networks.
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Li, Shuangde, Yuanjian Liu, Leke Lin, and Qi Sun. "Measurements and Characterization for Millimeter-Wave Massive MIMO Channel in High-Speed Railway Station Environment at 28 GHz." International Journal of Antennas and Propagation 2021 (October 26, 2021): 1–15. http://dx.doi.org/10.1155/2021/4580506.

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The millimeter-wave (mmWave) and massive multiple-input multiple-output (MIMO) wireless communication technologies provide vital means to resolve many technical challenges of the fifth-generation (5G) or beyond 5G (B5G) network. Analyzing the measured datasets extracted from the channel measurements can provide insight into the characteristics of radio channels in different scenarios. Therefore, mmWave massive MIMO channel measurements, simulation, and modeling are carried out in the high-speed railway waiting hall environments at 28 GHz. The multipath components (MPCs) parameters are estimated for line-of-sight (LOS) and non-line-of-sight (NLOS) scenarios based on the space-alternating generalized expectation-maximization (SAGE) algorithm. Delay spread (DS), azimuth angle of arrival (AAoA), and elevation angle of arrival (EAoA) are analyzed. And they are processed by using the K-mean algorithm. In addition, propagation characteristics are simulated based on the improved ray tracing method of shooting and bouncing ray tracing/image (SBR/IM). The correctness of the improved ray tracing method is verified by comparing the measured results with the simulated results. The large-scale path loss (PL) is characterized based on close-in (CI) free-space reference distance model and the floating-intercept (FI) path loss model. Furthermore, statistical distributions for root-mean-square delay spread (RMS DS) are investigated. The Gaussian distribution best fits the measured data of RMS delay spread. Finally, multipath clustering is identified using the multipath component distance (MCD). The analysis of these results from mmWave massive MIMO channel measurements and simulation may be instructive for the deployment of the 5G or B5G wireless communications systems at 28 GHz.
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Bartsiokas, Ioannis A., George K. Avdikos, and Dimitrios V. Lyridis. "Deep Learning-Based Beam Selection in RIS-Aided Maritime Next-Generation Networks with Application in Autonomous Vessel Mooring." Journal of Marine Science and Engineering 13, no. 4 (2025): 754. https://doi.org/10.3390/jmse13040754.

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Maritime communication networks are critical for supporting the increasing demands of oceanic and coastal activities, including shipping, fishing, and offshore operations. However, traditional systems face significant challenges in providing reliable, high-throughput connectivity due to dynamic sea environments, mobility, and non-line-of-sight (NLoS) conditions. Reconfigurable intelligent surfaces (RISs) have been proposed as a promising solution to overcome these limitations by enabling programmable control of electromagnetic wave propagation in next-generation mobile communication networks, such as beyond fifth generation and sixth generation ones (B5G/6G). This paper presents a deep learning-based (DL) scheme for beam selection in RIS-aided maritime next-generation networks. The proposed approach leverages deep learning to optimize beam selection dynamically, enhancing signal quality, coverage, and network efficiency in complex maritime environments. By integrating RIS configurations with data-driven insights, the proposed framework adapts to changing channel conditions and potential vessel mobility while minimizing latency and computational overhead. Simulation results demonstrate significant improvements in both machine learning (ML) metrics, such as beam selection accuracy, and overall communication reliability compared to traditional methods. More specifically, the proposed scheme reaches around 99% Top-K Accuracy levels while jointly improving energy efficiency (ee) and spectral efficiency (SE) by approx. 2 times compared to state-of-the-art approaches. This study provides a robust foundation for employing DL in RIS-aided maritime networks, contributing to the advancement of intelligent, high-performance wireless communication systems for advanced maritime applications, such as autonomous mooring, the autonomous approach, and just-in-time arrival (JIT).
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Elmezughi, Mohamed K., Omran Salih, Thomas J. Afullo, and Kevin J. Duffy. "Comparative Analysis of Major Machine-Learning-Based Path Loss Models for Enclosed Indoor Channels." Sensors 22, no. 13 (2022): 4967. http://dx.doi.org/10.3390/s22134967.

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Unlimited access to information and data sharing wherever and at any time for anyone and anything is a fundamental component of fifth-generation (5G) wireless communication and beyond. Therefore, it has become inevitable to exploit the super-high frequency (SHF) and millimeter-wave (mmWave) frequency bands for future wireless networks due to their attractive ability to provide extremely high data rates because of the availability of vast amounts of bandwidth. However, due to the characteristics and sensitivity of wireless signals to the propagation effects in these frequency bands, more accurate path loss prediction models are vital for the planning, evaluating, and optimizing future wireless communication networks. This paper presents and evaluates the performance of several well-known machine learning methods, including multiple linear regression (MLR), polynomial regression (PR), support vector regression (SVR), as well as the methods using decision trees (DT), random forests (RF), K-nearest neighbors (KNN), artificial neural networks (ANN), and artificial recurrent neural networks (RNN). RNNs are mainly based on long short-term memory (LSTM). The models are compared based on measurement data to provide the best fitting machine-learning-based path loss prediction models. The main results obtained from this study show that the best root-mean-square error (RMSE) performance is given by the ANN and RNN-LSTM methods, while the worst is for the MLR method. All the RMSE values for the given learning techniques are in the range of 0.0216 to 2.9008 dB. Furthermore, this work shows that the models (except for the MLR model) perform excellently in fitting actual measurement data for wireless communications in enclosed indoor environments since they provide R-squared and correlation values higher than 0.91 and 0.96, respectively. The paper shows that these learning methods could be used as accurate and stable models for predicting path loss in the mmWave frequency regime.
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25

Ly, Pham Thi, and Hoang Luu Thu Thuy. "Spatial distribution of hot days in north central region, Vietnam in the period of 1980-2013." VIETNAM JOURNAL OF EARTH SCIENCES 41, no. 1 (2019): 36–45. http://dx.doi.org/10.15625/0866-7187/41/1/13544.

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Based on the data of daily maximum temperature in 26 meteorological stations in the North Center Region, Vietnam over the period of 1980 to 2013, the authors conducted the research on the spatial distribution of the number of hot days. The initial result shows that in general, in the north of the study area, the large number of hot days occurred in the plain, and tended to decrease westward and eastward. In the south, this number tends to increase from the west to the east. Especially, the largest number occurred in two areas: The Ma and Ca River's valleys (Thanh Hoa and Nghe An provinces) and the coastal areas (Thua Thien Hue province), creating two heat centers in Tuong Duong district, Nghe An province and Nam Dong district, Thua Thien Hue province.ReferencesAdina-Eliza Croitoru, Adrian Piticar, Antoniu-Flavius Ciupertea, Cristina FlorinaRosca, 2016 Changes in heat wave indices in Romania over the period 1961-2015. Global and Plantary Change 146. Journal homepage: www. Elsevier.com/locate/gloplacha.Chu Thi Thu Huong et al., 2010. Variations and trends in hot event in Vietnam from 1961-2007, VNU Journal of Science and Technology, 26(3S).Climate Council, 2014a. Angry Summer 2013/2014. Accessed at http://www.climatecouncil.org.au/ angry-summer.Climate Council, 2014b. Angry Summer 2013/2014. Accessed at http://www.climatecouncil.org.au/ angry-summer.CSIRO and BoM, 2012. State of the Climate 2012.CSIRO and Bureau of Meteorology, Melbourne.Accessed at http://www.csiro.au/Outcomes/ Climate/Understanding/State-of-the-Climate-2012.aspx.D'Ippoliti D., Michelozzi P., Marino C., De'Donato F., Menne B., Katsouyanni K., Kirchmayer U., Analitis A., Medina-Ramon M., Paldy A., Atkinson R., Kovats S., Bisanti L., Schneider A., Lefranc A., Iñiguez C., Perucci C., 2010. The impact of heat waves on mortality in 9 European cities: results from the EuroHEAT project. Environ. Health 9, 37. http://dx.doi.org/10.1186/1476-069X-9-37.Gerald A. Meehl, 1992. Effect of tropical topography on global climate, Ann. Rev. Earth Planet. Sci., 20, 85-112.Hayhoe K., Cayan D., Field C.B., Frumhoff P.C., Maurer E.P., Miller N.L., Moser S.C., Schneider S.H., Cahill K.N., Cleland E.E., Dale L., Drapek R., Hanemann R.M., lkstein L.S., Lenihan J., Lunch C.K., Neilson R.P., Sheridan S.C., Verville J.H., 2004. Emissions pathways, climate change, and impacts on California. PNAS, 101(34), 12422-12427.Ho Thi Minh Ha, Phan Van Tan, 2009. Trends and variations of extreme temperature in Vietnam in the period from 1961 to 2007, VNU Journal of Science and Technology, 25(3S).IPCC, 2007: Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, Pachauri R.K and Reisinger A. (eds.)]. IPCC, Geneva, Switzerland, 104p.IPCC, 2014. Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R.K. Pachauri and L.A. Meyer (eds.)]. IPCC, Geneva, Switzerland, 151p.Liu G., Zhang L., He B., Jin X., Zhang Q., Razafindrabe B., You H., 2015. Temporal changes in extreme high temperature, heat waves and relevant disasters in Nanjing metropolitan region, China. Nat. Hazards, 76, 1415–1430. http://dx.doi.org/10.1007/s11069-014-1556-y.Manton M.J et al., 2001. Trends in extreme daily temperature in Southeast Asia Rainfall ad and the South Pacific, J. Climatol. 21.Nairn J.R., Fawcett R.J.B., 2015. Int. J. Environ. Res. Public Health 12, 227–253. http://dx.doi.org/10.3390/ijerph120100227.Nguyen Duc Ngu, 2009. Climate Change Challenges to development, Journal of Economy and Environment, No. 1.Perkins S.E., Alexander L.V., 2013. On the measurement of heat waves. J. Clim. 26, 4500–4517. http://dx.doi.org/10.1175/JCLI-D-12-00383.1.Peterson T.C., Heim Jr. R.R., Hirsch R., Kaiser D.P., Brooks H., Diffenbaugh N.S., Dole R.M., Giovannettone J.P., Guirguis K., Karl T.R., Katz R.W., Kunkel K., Lettenmaier D., McCabe G.J., Paciorek C.J., Ryberg K.R., Schubert S., Silva V.B.S., Stewart B.C., Vecchia A.V., Villarini G., Vose R.S., Walsh J., Wehner M., Wolock D., Wolter K., Woodhouse C.A., Wuebbles D., 2013. Monitoring and understanding changes in heat waves, cold waves, floods, and droughts in the United States: state of knowledge. Bull. Amer. Meteor. Soc., 94, 821–834.Pham Thi Ly, Hoang Luu Thu Thuy, 2015. Variation of heat waves in the North Central Region over the period of 1980-2013, Journal of natural resources and environment, 9, 81-89.Phan Van Tan et al., 2010. Study impact of global climate change on extreme weather phenomena and factors in Vietnam, prediction and adaptation strategies. Project final report, KC 08.29/06-10, Hanoi University of Science.Spinoni J., Lakatos M., Szentimrey T., Bihari Z., Szalai S., Vogt J., Antofie T., 2015. Heat and cold waves trends in Carpathian Region from 1961 to 2010. Int. J. Climatol, 35, 4197–4209. http://dx.doi.org/10.1002/joc.4279.Toreti A., Desiato F., 2008.Temperature trends over Italy from 1961 to 2004, Theor. Appl. Climatol 91.Tran Cong Minh, 2007. Principle of meteorology and climate, Book, Public House of Hanoi National University.Tran Quang Duc, Trinh Lan Phuong, 2013. Changes of Hot day and Fohn Activities at Ha Tinh- Central Vietnam, VNU Journal of Science, Science and Technology, 29(2S).Trewin B., Smalley R., 2013.Changes in extreme temperature in Australia, 1910 to 2011. In: 19th AMOS National Conference, Melbourne, 11-13.Unal Y.S., Tan E., Mentes S.S., 2013. Summer heat waves over western Turkey between 1965 and 2006.Theor. Appl. Climatol, 112, 339–350. http://dx.doi.org/10.1007/s00704-012-0704-0.Will Steffen, 2015. Quantifying the impact of climate change on extreme heat in Australia. Published by the Climate Council of Australia Limited. ISBN: 978-0-9942453-1-1 (print) 978-0-9942453-0-4 (web).
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26

Chenghu, Cui, Santichai Wicha, and Roungsan Chaisricharoen. "Analysing the EEG Signal Effectiveness of Chiang Rai Arabica Drip Coffee on Individual Human Brainwave." ECTI Transactions on Computer and Information Technology (ECTI-CIT) 13, no. 2 (2020): 178–87. http://dx.doi.org/10.37936/ecti-cit.2019132.194581.

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This study focused on the impact of local Arabica coffee on the level of attention of individual brain waves, and how coffee affects Human EEG Frequency. Local Arabica coffee is adopted in this study as a medium to wake up the Beta wave. The Personal brainwave data is then recorded through EEG equipment and classified. The result showed that local coffee is helping to improve people's attention level — the study conducted on fifty participants: twenty-five males and twenty-five females aged between twenty to thirty years old. Brainwaves or Electroencephalography are collected twice before and after drinking coffee to compare the effects of Arabica on human brain waves by using NeuroSky mindwave mobile. The paired sample t-test test was employed for comparing two groups of Beta brainwaves experiment. Besides, the k-means algorithm is used to perform data mining on brain waves, and the differential brain wave signal data is clustered and divided into three levels. The experimental results showed that there was a statistically significant difference between the two paired samples. Therefore, the results confirmed that local Arabica coffee has a direct impact on personal attention.
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Raden Sri Martini Meilanie, Winda Gunarti, and Astari Yaumil Hassan. "Parents' Perceptions of Children's School Readiness During and After the COVID-19 Pandemic." JPUD - Jurnal Pendidikan Usia Dini 16, no. 1 (2022): 162–71. http://dx.doi.org/10.21009/jpud.161.11.

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Children's school readiness is important to discuss because learning loss is an obstacle in preparing early childhood to enter elementary school. This study aims to look at parents' perceptions of their children's readiness for school during and after the COVID-19 pandemic. This study uses a quantitative descriptive survey research design to collect measurable data for statistical analysis from a population sample. The results show that preparing children for school during and after the COVID-19 pandemic is very different from the usual practice. Parents are required to provide appropriate stimulation to children at home to replace the role of teachers at school and restore the motivation and willingness of children to enter elementary school. The perception of parents is certainly very influential on the stimulation that will be given to children.
 Keywords: early childhood education, parents’ perceptions, school readiness
 References:
 Alexander, K. L., Entwisle, D. R., & Olson, L. S. (2007). Lasting Consequences of the Summer Learning Gap. American Sociological Review, 72(2), 167–180. https://doi.org/10.1177/000312240707200202
 Araújo, L. A. de, Veloso, C. F., Souza, M. de C., Azevedo, J. M. C. de, & Tarro, G. (2021). The potential impact of the COVID-19 pandemic on child growth and development: A systematic review. Jornal de Pediatria, 97(4), 369–377. https://doi.org/10.1016/j.jped.2020.08.008
 Atkinsonová, R. L., Atkinson, R. C., SMITH, E. E., Herman, E., Bem, D. J., & Petržela, M. (1995). Psychologies. Victoria Publishing. https://books.google.co.id/books?id=Tj9OAAAACAAJ
 Bao, X., Qu, H., Zhang, R., & Hogan, T. P. (2020). Modeling Reading Ability Gain in Kindergarten Children during COVID-19 School Closures. International Journal of Environmental Research and Public Health, 17(17). https://doi.org/10.3390/ijerph17176371
 Benner, A. D., & Mistry, R. S. (2020). Child Development During the COVID-19 Pandemic Through a Life Course Theory Lens. Child Development Perspectives, 14(4), 236–243. https://doi.org/10.1111/cdep.12387
 Brown, S. M., Doom, J. R., Lechuga-Peña, S., Watamura, S. E., & Koppels, T. (2020). Stress and parenting during the global COVID-19 pandemic. Child Abuse & Neglect, 110, 104699. https://doi.org/10.1016/j.chiabu.2020.104699
 Colizzi, M., Sironi, E., Antonini, F., Ciceri, M. L., Bovo, C., & Zoccante, L. (2020). Psychosocial and Behavioral Impact of COVID-19 in autism spectrum disorder: An Online Parent Survey. Brain Sciences, 10(6). https://doi.org/10.3390/brainsci10060341
 Creswell, J. W. (2015). Educational research: Planning, conducting, and evaluating quantitative and qualitative research (Fifth edition). Pearson.
 Cushon, J. A., Vu, L. T. H., Janzen, B. L., & Muhajarine, N. (2011). Neighborhood Poverty Impacts Children’s Physical Health and Well-Being Over Time: Evidence from the Early Development Instrument. Early Education and Development, 22(2), 183–205. https://doi.org/10.1080/10409280902915861
 Duncan, R. J., Duncan, G. J., Stanley, L., Aguilar, E., & Halfon, N. (2020). The kindergarten Early Development Instrument predicts third grade academic proficiency. Early Childhood Research Quarterly, 53, 287–300. https://doi.org/10.1016/j.ecresq.2020.05.009
 Engzell, P., Frey, A., & Verhagen, M. D. (2021). Learning loss due to school closures during the COVID-19 pandemic. Proceedings of the National Academy of Sciences, 118(17), e2022376118. https://doi.org/10.1073/pnas.2022376118
 Friedman, M. M., Bowden, V. R., & Jones, E. (2003). Family Nursing: Research, Theory & Practice. Prentice Hall. https://books.google.co.id/books?id=mkBtAAAAMAAJ
 Gobbi, E., Maltagliati, S., Sarrazin, P., di Fronso, S., Colangelo, A., Cheval, B., Escriva-Boulley, G., Tessier, D., Demirhan, G., Erturan, G., Yüksel, Y., Papaioannou, A., Bertollo, M., & Carraro, A. (2020). Promoting Physical Activity during School Closures Imposed by the First Wave of the COVID-19 Pandemic: Physical Education Teachers’ Behaviors in France, Italy and Turkey. International Journal of Environmental Research and Public Health, 17(24). https://doi.org/10.3390/ijerph17249431
 Griffith, A. K. (2020). Parental Burnout and Child Maltreatment During the COVID-19 Pandemic. Journal of Family Violence. https://doi.org/10.1007/s10896-020-00172-2
 Hevia, F. J., Vergara-Lope, S., Velásquez-Durán, A., & Calderón, D. (2022). Estimation of the fundamental learning loss and learning poverty related to COVID-19 pandemic in Mexico. International Journal of Educational Development, 88, 102515. https://doi.org/10.1016/j.ijedudev.2021.102515
 Jandrić, P. (2020). Postdigital Research in the Time of Covid-19. Postdigital Science and Education, 2(2), 233–238. https://doi.org/10.1007/s42438-020-00113-8
 Kuhfeld, M., Tarasawa, B., Johnson, A., Ruzek, E., & Lewis, K. (2020). Initial findings on students’ reading and math achievement and growth. 12.
 Maldonado, J. E., & De Witte, K. (2022). The effect of school closures on standardised student test outcomes. British Educational Research Journal, 48(1), 49–94. https://doi.org/10.1002/berj.3754
 McDowell, K., Jack, A., & Compton, M. (2018). Parent Involvement in Pre-Kindergarten and the Effects on Student Achievement. The Advocate, 23(6). https://doi.org/10.4148/2637-4552.1004
 Nevid, J. S. (2012). Psychology: Concepts and Applications. Wadsworth Cengage Learning. https://books.google.co.id/books?id=TpxZXwAACAAJ
 Skulmowski, A., & Rey, G. D. (2020). COVID-19 as an accelerator for digitalization at a German university: Establishing hybrid campuses in times of crisis. Human Behavior and Emerging Technologies, 2(3), 212–216. https://doi.org/10.1002/hbe2.201
 Spinelli, M., Lionetti, F., Pastore, M., & Fasolo, M. (2020). Parents’ Stress and Children’s Psychological Problems in Families Facing the COVID-19 Outbreak in Italy. Frontiers in Psychology, 11, 1713. https://doi.org/10.3389/fpsyg.2020.01713
 Yoshikawa, H., Wuermli, A. J., Britto, P. R., Dreyer, B., Leckman, J. F., Lye, S. J., Ponguta, L. A., Richter, L. M., & Stein, A. (2020). Effects of the Global Coronavirus Disease-2019 Pandemic on Early Childhood Development: Short- and Long-Term Risks and Mitigating Program and Policy Actions. The Journal of Pediatrics, 223, 188–193. https://doi.org/10.1016/j.jpeds.2020.05.020
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Sakai, Marika, Riyan Achmad Budiman, Mina Yamaguchi, Keiji Yashiro та Tatsuya Kawada. "Determination of Oxygen Reduction Reaction Process of La0.6Sr0.4CoO3- δ Porous Electrode Using Nonlinear Frequency Response Analysis". ECS Meeting Abstracts MA2024-02, № 48 (2024): 3427. https://doi.org/10.1149/ma2024-02483427mtgabs.

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Electrochemical impedance spectroscopy (EIS) is a method to measure the performance of an electrochemical cell where linear responses are obtained when a small perturbation of current or voltage is applied to the cell. It is so often that different limiting steps of electrochemical processes give similar responses of the impedance spectrum. Therefore, the typical linear EIS measurements are not sufficient to understand the electrode reaction mechanism. On the other side, the frequency response analysis including nonlinearities can provide more information in addition to EIS, and is considered an advanced method to understand the reaction mechanism as reported by the research group of S. Adler [1,2]. In EIS, the small perturbation is applied to the cell so that the input and output can be regarded as a linear relationship. Meanwhile, in the non-linear electrochemical impedance spectroscopy (NLEIS) large perturbation is applied to the cell. In this way, NLEIS can visualize not only the fundamental waveform but also the changes in the harmonics, which is expected to enable more detailed analysis and reaction modeling. Using the above principles in potentiostatic mode, this study aims to elucidate the ORR process of La0.6Sr0.4CoO3- δ (LSC) porous electrode for SOFC cathode. A symmetrical cell was prepared by depositing LSC porous electrodes on both sides of a Gd0.1Ce0.9O1.95 electrolyte. The experiments were performed in I-V measurements and NLEIS as a function of temperature (873 – 1073 K) under various p(O2) (1 – 10-4 bar). An electrochemical workstation (Zahner Zennium, Zahner-Elektrik GmbH & Co. KG, Germany) was used for the measurement to obtain the non-linear response. The obtained harmonics are normalized by the amplitude of the fundamental wave after Fourier transformation, and data are output up to the fifth harmonic. NLEIS was performed at frequencies from 0.1 Hz to 1M Hz. The experimental results showed clear response at the second harmonic with the magnitude increasing and phase changing as the frequency decreased. Harmonic components tended to increase with decreasing p(O2) and increasing temperature. In addition to experiments, the simulation using an electric circuit simulator (LTspice, Analog Devices) was performed. As an equivalent circuit of a mixed-conducting porous electrode, a ladder circuit has been applied to analyze the nonlinear response. The currents related to ion diffusion were defined based on the Nernstian Einstein equation, and the currents related to surface reactions were defined based on an empirical model of oxygen adsorption and dissociation[3]. The result showed that the 1st harmonic and 2nd harmonic responses from the experimental result is in good agreement with the simulation results from LTspice at high p(O2) (1 – 10-2 bar) in the terms of the shape and phase of the response. At low p(O2) (10-3 – 10-4 bar), the effect of gas diffusion resistance could not be ignored.. The complete analysis on ORR process as a function of the p(O2) and temperature will be discussed after resolving technical issues related to computational convergence when gas diffusion resistance is included into the equivalent circuit. References [1] J. R. Wilson, D. T. Schwartz, S. B. Adler, Electrochim. Acta, 51, 1389–1402 (2006). [2] J. R. Wilson, M. Sase, T. Kawada, S. B. Adler, Electrochem. Solid-State Lett., 10, B81-B86 (2007). [3]T. Kawada, Current Opinion in Electrochemistry, 21, 274-282(2020) Acknowledgement This study is supported by ministry of environment, Japan, for Carbon Neutral Technology Research and Development Program.
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Mangini, Lauren D., Mark D. Hayward, Yeyi Zhu, Yongquan Dong, and Michele R. Forman. "Timing of household food insecurity exposures and asthma in a cohort of US school-aged children." BMJ Open 8, no. 11 (2018): e021683. http://dx.doi.org/10.1136/bmjopen-2018-021683.

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ObjectiveFood insecurity is positively associated with asthma, the most common chronic childhood disease, yet directionality is unclear. The objective was to determine the association between exposure to food insecurity in early childhood and the odds of asthma later in childhood.DesignData from four waves of the Early Childhood Longitudinal Study-Kindergarten (ECLS-K) cohort, a prospective, dual-frame, multistage probability cluster sampling study of school-aged US children were entered in multivariate logistic regression models, adjusted for covariates. Exposures to food insecurity were based on parental responses to the validated USDA 18-item module at each wave.SettingPublic and private primary and secondary schools between 1998 and 2007.ParticipantsAt its inception (1999), the ECLS-K had 20 578 kindergarteners; by the spring of eighth grade (2007), the cohort dropped to 9725 due to attrition. Children missing an exposure, outcome or confounding variable were excluded, final n=6731.Primary outcome measureChild’s diagnosis of asthma by a healthcare professional as reported by the parent.ResultsHousehold food insecurity (vs food security) in the year before kindergarten and in second grade had a higher odds of asthma by 18% (95% CI 1.17 to 1.20) and 55% (95% CI 1.51 to 1.55). After removing asthmatics before third grade from the model, food insecurity in second grade was associated with higher odds of asthma at fifth or eighth grades (OR 1.55; 95% CI 1.53 to 1.58), whereas food insecurity in the year before kindergarten had a lower odds at fifth or eighth grades.ConclusionsFood insecurity in the year before kindergarten and in second grade were associated with a higher odds of asthma in third grade. Food insecurity in second grade retained the signal for increased odds of asthma after third and through eighth grades. Additional research is needed to explore childhood windows of vulnerability to asthma.
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Shbaklo, Nour, Silvia Corcione, Costanza Vicentini, et al. "An Observational Study of MDR Hospital-Acquired Infections and Antibiotic Use during COVID-19 Pandemic: A Call for Antimicrobial Stewardship Programs." Antibiotics 11, no. 5 (2022): 695. http://dx.doi.org/10.3390/antibiotics11050695.

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The pandemic caused by the COVID-19 virus has required major adjustments to healthcare systems, especially to infection control and antimicrobial stewardship. The objective of this study was to describe the incidence of multidrug-resistant (MDR) hospital-acquired infections (HAIs) and antibiotic consumption during the three waves of COVID-19 and to compare it to the period before the outbreak at Molinette Hospital, located in the City of Health and Sciences, a 1200-bed teaching hospital with surgical, medical, and intensive care units. We demonstrated an increase in MDR infections: particularly in K. pneumoniae carbapenemase-producing K. pneumoniae (KPC-Kp), A. baumannii, and MRSA. Fluoroquinolone use showed a significant increasing trend in the pre-COVID period but saw a significant reduction in the COVID period. The use of fourth- and fifth-generation cephalosporins and piperacillin–tazobactam increased at the beginning of the COVID period. Our findings support the need for restoring stewardship and infection control practices, specifically source control, hygiene, and management of invasive devices. In addition, our data reveal the need for improved microbiological diagnosis to guide appropriate treatment and prompt infection control during pandemics. Despite the infection control practices in place during the COVID-19 pandemic, invasive procedures in critically ill patients and poor source control still increase the risk of HAIs caused by MDR organisms.
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Bizhigitov, T., and G. H. Orazymbetova. "INVESTIGATION OF THE EFFECT OF TEMPERATURE ON THE ELASTIC AND THERMAL PROPERTIES OF THE TYPE OF ICE 1H ON THE ICE PHASE DIAGRAM." Bulletin of Dulaty University 17, no. 1 (2025): 247–54. https://doi.org/10.55956/jixz7552.

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In the scientific article, for the first time, changes in the velocities and volumes of ultrasonic waves in the form of 1h ice in the phase diagram of low temperature and high pressure ice between pressures of 300 MPa and 500 MPa and temperatures of (100-170) K were experimentally measured and the temperature dependences of the coefficient of volumetric thermal increase, reduced and Debye temperature and specific heat capacity at constant pressures were theoretically calculated., graphs were plotted. The measurement of the temperature dependence of the sample volume change in the research work allowed us to estimate the coefficient of thermal volumetric increase. 1h we found the calculation of the coefficient of volumetric increase in the type of ice with isobaric changes before the phase transformation by differentiating the graph V =V(T). An installation was assembled to carry out experimental measurements. Its first part consists of a three–layer piston–cylindrical chamber operating at high pressure (0-2500 MPa) and a lower one (90-250 K), and the second part consists of a measuring device that automatically changes and controls the temperature and pressure of the sample located inside the chamber, the third consists of an ultrasonic pulse system measuring the velocity of elastic waves propagating in the form of the ice under study is 1H lives. Measurements of piston movements, changes in temperature and pressure of the sample were carried out using an automated system. The installation was tested by studying the transformations of ice types from one state to another, the third, fifth, sixth on the phase diagram in the P – T coordinate of the ice. The result obtained on the installation we have assembled coincides with the result obtained by the author of the scientific article.
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Brando, Guilherme, Kazuya Koyama, and Hans A. Winther. "Revisiting Vainshtein screening for fast N-body simulations." Journal of Cosmology and Astroparticle Physics 2023, no. 06 (2023): 045. http://dx.doi.org/10.1088/1475-7516/2023/06/045.

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Abstract We revisit a method to incorporate the Vainshtein screening mechanism in N-body simulations proposed by R. Scoccimarro in [1]. We further extend this method to cover a subset of Horndeski theories that evade the bound on the speed of gravitational waves set by the binary neutron star merger GW170817. The procedure consists of the computation of an effective gravitational coupling that is time and scale dependent, G eff (k,z), where the scale dependence will incorporate the screening of the fifth-force. This is a fast procedure that when contrasted to the alternative of solving the full equation of motion for the scalar field inside N-body codes, reduces considerably the computational time and complexity required to run simulations. To test the validity of this approach in the non-linear regime, we have implemented it in a COmoving Lagrangian Approximation (COLA) N-body code, and ran simulations for two gravity models that have full N-body simulation outputs available in the literature, nDGP and Cubic Galileon. We validate the combination of the COLA method with this implementation of the Vainshtein mechanism with full N-body simulations for predicting the boost function: the ratio between the modified gravity non-linear matter power spectrum and its General Relativity counterpart. This quantity is of great importance for building emulators in beyond-ΛCDM models, and we find that the method described in this work has an agreement of below 2% for scales down to k ≈ 3h/Mpc with respect to full N-body simulations.
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Johnston, E. A., K. S. Petersen, and P. M. Kris-Etherton. "Daily intake of non-fried potato does not affect markers of glycaemia and is associated with better diet quality compared with refined grains: a randomised, crossover study in healthy adults." British Journal of Nutrition 123, no. 9 (2020): 1032–42. http://dx.doi.org/10.1017/s0007114520000252.

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AbstractEpidemiological studies suggest that consumption of potatoes is associated with increased risk of cardiometabolic diseases. However, few clinical trials have empirically tested this. The aim of this single-blind, randomised, crossover study was to evaluate the effect of daily potato consumption, compared with refined grains, on risk factors for cardiometabolic diseases. It was hypothesised that no difference in cardiometabolic endpoints would be detected between conditions, but diet quality would improve with potato consumption. Healthy participants on self-selected diets received one potato-based side dish or one refined grain-based side dish daily, for 4 weeks, separated by a minimum 2-week break. Dishes were isoenergetic, carbohydrate-matched and prepared without excess saturated fat or Na. Participants were instructed to consume the side dish with a meal in place of carbohydrates habitually consumed. Lipids/lipoproteins, markers of glycaemic control, blood pressure, weight and pulse wave velocity were measured at baseline and condition endpoints. Diet quality was calculated, based on 24-h recalls, using the Healthy Eating Index (HEI)-2015. Fifty adults (female n 34; age 40 (sd 13) years; BMI 24·5 (sd 3·6) kg/m2) completed the present study. No between-condition differences were detected for fasting plasma glucose (–0·05 mmol/l, 95 % CI –0·14, 0·04; P = 0·15), the primary outcome or any other outcomes. Compared with refined grains, the HEI-2015 score (3·5, 95 % CI 0·6, 6·4; P = 0·01), K (547 mg, 95 % CI 331, 764, P < 0·001) and fibre (2·4 g, 95 % CI 0·6, 4·2, P = 0·01) were higher following the potato condition. Consuming non-fried potatoes resulted in higher diet quality, K and fibre intake, without adversely affecting cardiometabolic risk.
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Eon, Rehman, Aaron Gerace, Lucy Falcon, et al. "Validation of Landsat-9 and Landsat-8 Surface Temperature and Reflectance during the Underfly Event." Remote Sensing 15, no. 13 (2023): 3370. http://dx.doi.org/10.3390/rs15133370.

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With the launch of Landsat-9 on 27 September 2021, Landsat continues its fifty-year continuity mission of providing users with calibrated Earth observations. It has become a requirement that an underflight experiment be performed during commissioning to support sensor cross-calibration. In this most recent experiment, Landsat-9 flew under Landsat-8 for nearly three days with over 50% ground overlap, from 13 to 15 November 2021. To address the scarcity of reference data that are available to support calibration and validation early-on in the mission, a ground campaign was planned and executed by the Rochester Institute of Technology (RIT) on 14 November 2021 to provide full spectrum measurements for early mission comparisons. The primary experiment was conducted in the Outer Banks, North Carolina at Jockey’s Ridge Sand Dunes. Full-spectrum ground-based measurements were acquired with calibrated reference equipment, while a novel Unmanned Aircraft System (UAS)-based platforms acquired hyperspectral visible and near-infrared (VNIR)/Short-wave infrared (SWIR) imagery data and coincident broadband cooled thermal infrared (TIR) imagery. Results of satellite/UAS/ground comparisons were an indicator, during the commissioning phase, that Landsat-9 is behaving consistently with Landsat-8, ground reference, and UAS measurements. In the thermal infrared, all measurements agree to be within 1 K over water and to within 2 K over sand, which represents the most challenging material for estimating surface temperature. For the surface reflectance product(s), Landsat-8 and -9 are in good agreement and only deviate slightly from ground reference in the SWIR bands; a deviation of 2% in the VNIR and 5–8% in the SWIR regime. Subsequent longer-term studies indicate that Landsat 9 continues to perform as expected. The behavior of Thermal Infrared Sensor-2 (TIRS-2) against reference is also shown for the first year of the mission to illustrate its consistent performance.
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Shamraeva, Daria, and Sergiy Vozianon. "Metabolic changes in bladder cancer patients after urinary tract reconstruction using intestinal segments." Ukrainian Scientific Medical Youth Journal 146, no. 2 (2024): 84–97. http://dx.doi.org/10.32345/usmyj.2(146).2024.84-97.

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The goal is to evaluate the occurrence of short-term and long-term metabolic changes in patients with muscle-invasive bladder cancer (MIBC) after radical cystectomy (RCE) followed by orthotopic derivation of urine from segments of the small intestine or the formation of an ileal conduit with a "wet stoma" exit. During 2018-2020, the SI "Academician O.F. Vozianov Institute of Urology National Academy of Sciences of Ukraine" conducted examinations and treatments 22 patients diagnosed with MIBC at clinical stages T2aN0M0–T3bN0M0. In all cases, radical cystectomy and lymphadenectomy were performed using the laparoscopic method, but 8 (36.4%) patients had previously undergone open resection of the urinary bladder in other medical institutions. In five patients (22.7%), urine derivation was performed by the method of creating an ileal conduit according to Bricker. Eight (36.4%) patients underwent ileoneocystoplasty according to Studer, in nine (40.9%) patients, an orthotopic neocist was performed according to a modification of the 4 department of SI "Academician O.F.Vozianov Institute of Urology National Academy of Sciences of Ukraine", which consists in creating an orthotopic artificial bladder from a pre-resected segment of the ileum and anastomosing it with the proximal part of the urethra and the distal segments of the ureters, which differs from the commonly known method of ileonecystoplasty according to Studer in that, firstly, in the course of its implementation, the possibility of an instrumental intestinal suture is foreseen in the case of endoscopic variants of radical cystprostatectomy, and the length of the necessary ileal fragment was reduced to 50 cm. Second, a complete detubularization of the conventionally divided into right, middle and left segments of the intestine fragment: asymmetrically during its middle 5 cm with the formation of a cervical flap, and symmetrically - along the contramesenteric edge on the entire other length. Third, the medial edges of the right and left intestinal segments were first fixed to the upper edge of the middle segment. Fourth, after the creation of the eye of the neck of the future "neovesica", the upper and middle thirds of the lateral edge of the right and left intestinal segments were fastened together. Fifth, the original neck of the new intestinal bladder was formed by making vertical incisions of the pre-created eye of the reservoir neck at 12 and 6 o'clock of the conventional dial to expand its diameter to 1.0–1.5 cm, then step-by-step eversion and tubularization of the formed semicircles were performed on the urethral catheter by applying 3–5 knotted Vicryl 3.0 sutures and performing a neck duplication maneuver with two knotted sero-muscular sutures placed one above the other parallel to the axis of the neck with a step between the puncture and the puncture of the needle of 4 mm. Sixth, after the formation of the vesico-urethral anastomosis, the free edges of the cervical flap and the lower thirds of the lateral edge of the right and left intestinal segments were sutured, the oral and aboral intestinal openings were sealed, a cystostomy drainage was installed through the latter, and a reversible peritonization maneuver was performed. To compare the results of the study based on postoperative metabolic changes, all patients were divided into three groups: 1st group (5 patients) - with urine derivation according to Bricker, 2nd group (8 patients) - with ileoneocystoplasty according to Studer, 3rd group (9 patients) - which urine derivation was carried out orthotopically in a modification of the clinic (neocyst). To evaluate the advantages of our proposed method of creating an artificial bladder, the following indicators were evaluated: bladder volume, kidney concentration function (urine density), diarrhea after surgery, hypokalemia, the appearance of kidney stones, and kidney function was also evaluated according to the glomerular filtration rate (GFR). After the operation, the volume of the bladder or conduit changed depending on the group: it increased in patients of groups 2 and 3 (during the operation: group 2 – 380,0±1,4 ml, group 3 – 170,0±24,2 ml, after 6 months: 420,0±81,4 ml and 310,0±62,5 ml, respectively), but decreased in patients of group 1 (during surgery: 30,0±3,4 ml, after 6 months – 13,0±2,2 ml). Urine density indicators before the operation were within the normal range in all groups: 1st group – 1020,0±3,8; 2nd group – 1016,0±2,9; 3rd group – 1019,0±3,9. No changes in the concentration function were observed even after the operation according to Bricker (1015,0±5,0) one year after the operation. On the other hand, when performing orthotopic ileoneocystoplasty, an increase in the concentration function of the kidneys was noted (group 2 – 1050,0±7,3, group 3 – 1035,0±17,0). Diarrhea was observed in all patients after the start of feeding, but its duration was different. In patients with orthotopic methods, the duration of diarrhea was longer (group 1 – 3,0±1,2 days and was not observed 12 months after surgery, group 2 – 10,0±3,9 days, group 3 – 7,0±1,6 days). One year after the operation, two patients of group 2 and one of group 3 noted the presence of liquid stool once a day. In some patients of groups 2 and 3, a violation of the acid-alkaline balance was noted, which required correction: p/o HCO3− in group 2 – 19,0±1,6 mmol/l; in group 3 – 20,0±1,6 mmol/l. 1 year after surgery HCO3− in group 2 – 23,0±1,4 mmol/l; in group 3 – 24,0±1,6 mmol/l. Group 1 patients did not show changes in acid-base balance either in the early postoperative period or after one year (HCO3− immediately after surgery – 23,0±1,4 mmol/l, after 1 year – 24,0±1,4 mmol/l). In group 1, the concentration of K+ in serum immediately after surgery tended to decrease, but never exceeded the lower limit of normal (3,3±0,1 mmol/l) and there were no deviations one year after surgery (4,0±0,6 mmol/l). Among patients with orthotopic urine diversion, the most pronounced changes were observed in patients of group 2, where hypokalemia could reach 2,6±0,№ mmol/l immediately after surgery. Group 3 patients also showed a decrease in serum K+ after surgery (3,0±0,2 mmol/l), but these indicators were less pronounced and the patients were more likely to undergo medical correction. 1 year after the operation, a satisfactory concentration of K+ in blood serum was observed after conservative measures in groups 2 and 3 and amounted to 3,8±0,6 mmol/l and 4,3±0,9 mmol/l, respectively. Kidney calculi were found in two patients of group 1, one of them underwent remote shock wave lithotripsy 7 months after the operation, the second patient took citrate mixtures until the calculi completely regressed. In the second group there was 1 patient with kidney microliths who is under observation. No cases of urolithiasis were registered in group 3. A general decrease in GFR was found in all groups, but was more pronounced in patients of group 1 (GFR before surgery – 93,0±4,1 ml/min, 1 year after surgery – 35,0±6,9 ml/min). Of the patients in groups 2 and 3, the latter demonstrated the lowest rates of glomerular filtration reduction (108,0±13,4 ml/min before surgery and 93,0±14,5 ml/min after 1 year in patients of group 3 versus 95,0±3,8 ml/min before surgery and 84,0±12,8 ml/min after 1 year in patients of group 2). Modification of performing intracorporeal laparoscopic formation of an orthotopic neocyst according to the methodology of the 4th Department of Urology of the SI "Academician O.F.Vozianov Institute of Urology National Academy of Sciences of Ukraine" did not lead to the occurrence of uncontrolled metabolic disorders in the early and late postoperative periods in patients with MIBC and can be recommended for wider implementation in the clinical practice of urological and surgical departments of medical institutions of Ukraine.
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Pradhan, Bikram Keshari, Dhruv Pathak, and Debarati Chatterjee. "Constraining Nuclear Parameters Using Gravitational Waves from f-mode Oscillations in Neutron Stars." Astrophysical Journal 956, no. 1 (2023): 38. http://dx.doi.org/10.3847/1538-4357/acef1f.

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Abstract Gravitational waves (GWs) emanating from unstable quasi-normal modes in neutron stars (NSs) could be accessible with the improved sensitivity of the current GW detectors or with the next-generation GW detectors and, therefore, can be employed to study the NS interior. Assuming f-mode excitation in isolated pulsars with typical energy of pulsar glitches and considering potential f-mode GW candidates for A+ (upgraded LIGO detectors operating at fifth observing run design sensitivity) and Einstein Telescope (ET), we demonstrate the inverse problem of NS asteroseismology within a Bayesian formalism to constrain the nuclear parameters and NS equation of state (EOS). We describe the NS interior within relativistic mean-field formalism. Taking the example of glitching pulsars, we find that for a single event in A+ and ET, among the nuclear parameters, the nucleon effective mass (m*) within 90% credible interval can be restricted within 10% and 5%, respectively. At the same time, the incompressibility (K) and the slope of the symmetry energy (L) are only loosely constrained. Considering multiple (10) events in A+ and ET, all the nuclear parameters are well constrained, especially m*, which can be constrained to 3% and 2% in A+ and ET, respectively. Uncertainty in the observables of a 1.4 M ⊙ NS such as radius ( R 1.4 M ⊙ ), f-mode frequency ( f 1.4 M ⊙ ), damping time ( τ 1.4 M ⊙ ), and a few EOS properties including squared speed of sound (c s 2) are also estimated.
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BERTOLOTTI, FABIO P. "The influence of rotational and vibrational energy relaxation on boundary-layer stability." Journal of Fluid Mechanics 372 (October 10, 1998): 93–118. http://dx.doi.org/10.1017/s0022112098002353.

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We investigate the influence of rotational and vibrational energy relaxation on the stability of laminar boundary layers in supersonic flows by numerically solving the linearized equations of motion for a flow in thermal non-equilibrium. We model air as a mixture of nitrogen, oxygen and carbon dioxide, and derive accurate models for the relaxation rates from published experimental data in the field of physical chemistry. The influence of rotational relaxation is to dampen high-frequency instabilities, consistent with the well known damping effect of rotational relaxation on acoustical waves. The influence of rotational relaxation can be modelled with acceptable accuracy through the use of the bulk-viscosity approximation when the bulk viscosity is computed with a formula described herein. Vibrational relaxation affects the growth of disturbances by changing the characteristics of the laminar mean flow. The influence is strongest when the flow field contains a region at, or near, stagnation conditions, followed by a rapid expansion, such as inside wind tunnels and around bodies with a blunt leading edge, whereby the rapid expansion causes the internal energy to freeze in a distribution out of equilibrium. For flows at Mach 4.5 and stagnation temperature of 1000 K, the total amplification exhibited by boundary-layer disturbances over a sharp flat plate in wind-tunnel flows can reach a value that is fifty times as high as the value computed under the assumption of thermal equilibrium. The difference in amplification can be twice as high in the case of a blunt flat plate at atmospheric flight conditions.
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Hens, Luc, Nguyen An Thinh, Tran Hong Hanh, et al. "Sea-level rise and resilience in Vietnam and the Asia-Pacific: A synthesis." VIETNAM JOURNAL OF EARTH SCIENCES 40, no. 2 (2018): 127–53. http://dx.doi.org/10.15625/0866-7187/40/2/11107.

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Climate change induced sea-level rise (SLR) is on its increase globally. Regionally the lowlands of China, Vietnam, Bangladesh, and islands of the Malaysian, Indonesian and Philippine archipelagos are among the world’s most threatened regions. Sea-level rise has major impacts on the ecosystems and society. It threatens coastal populations, economic activities, and fragile ecosystems as mangroves, coastal salt-marches and wetlands. This paper provides a summary of the current state of knowledge of sea level-rise and its effects on both human and natural ecosystems. The focus is on coastal urban areas and low lying deltas in South-East Asia and Vietnam, as one of the most threatened areas in the world. About 3 mm per year reflects the growing consensus on the average SLR worldwide. The trend speeds up during recent decades. The figures are subject to local, temporal and methodological variation. In Vietnam the average values of 3.3 mm per year during the 1993-2014 period are above the worldwide average. Although a basic conceptual understanding exists that the increasing global frequency of the strongest tropical cyclones is related with the increasing temperature and SLR, this relationship is insufficiently understood. Moreover the precise, complex environmental, economic, social, and health impacts are currently unclear. SLR, storms and changing precipitation patterns increase flood risks, in particular in urban areas. Part of the current scientific debate is on how urban agglomeration can be made more resilient to flood risks. Where originally mainly technical interventions dominated this discussion, it becomes increasingly clear that proactive special planning, flood defense, flood risk mitigation, flood preparation, and flood recovery are important, but costly instruments. Next to the main focus on SLR and its effects on resilience, the paper reviews main SLR associated impacts: Floods and inundation, salinization, shoreline change, and effects on mangroves and wetlands. The hazards of SLR related floods increase fastest in urban areas. This is related with both the increasing surface major cities are expected to occupy during the decades to come and the increasing coastal population. In particular Asia and its megacities in the southern part of the continent are increasingly at risk. The discussion points to complexity, inter-disciplinarity, and the related uncertainty, as core characteristics. An integrated combination of mitigation, adaptation and resilience measures is currently considered as the most indicated way to resist SLR today and in the near future.References Aerts J.C.J.H., Hassan A., Savenije H.H.G., Khan M.F., 2000. Using GIS tools and rapid assessment techniques for determining salt intrusion: Stream a river basin management instrument. 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Urbanization and climate change impacts on future urban flooding in Can Tho city, Vietnam. Hydrol. Earth Syst. Sci., 17, 379-394. Doi: 10.5194/hess-17-379-2013. Hurlimann A., Barnett J., Fincher R., Osbaldiston N., Montreux C., Graham S., 2014. Urban planning and sustainable adaptation to sea-level rise. Landscape and Urban Planning, 126, 84-93. Doi: 10.1016/j.landurbplan.2013.12.013. IMHEN-Vietnam Institute of Meteorology, Hydrology and Environment, 2011. Climate change vulnerability and risk assessment study for Ca Mau and KienGiang provinces, Vietnam. Hanoi, Vietnam Institute of Meteorology, Hydrology and Environment (IMHEN), 250p. IMHEN-Vietnam Institute of Meteorology, Hydrology and Environment, Ca Mau PPC, 2011. Climate change impact and adaptation study in The Mekong Delta - Part A: Ca Mau Atlas. Hanoi, Vietnam: Institute of Meteorology, Hydrology and Environment (IMHEN), 48p. IPCC-Intergovernmental Panel on Climate Change, 2014. Fifth assessment report. 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39

Korus, K. A., A. D. Timmerman, R. D. French-Monar, and T. A. Jackson. "First Report of Goss's Bacterial Wilt and Leaf Blight (Clavibacter michiganensis subsp. nebraskensis) of Corn in Texas." Plant Disease 95, no. 1 (2011): 73. http://dx.doi.org/10.1094/pdis-07-10-0541.

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In September 2009, the University of Nebraska–Lincoln Plant and Pest Diagnostic Clinic received leaf samples of hybrid corn (Zea mays L.) displaying long, necrotic lesions with wavy margins. The lesions had discontinuous water-soaked spots that are indicative of Goss's bacterial wilt and leaf blight. The symptomatic leaves were submitted from Dallam County, located in the Texas Panhandle (northwest Texas). According to the USDA Farm Service Agency and the National Agricultural Statistics Service, in 2009 Dallam County had 54,025 ha planted to corn. This is approximately 19% of the total corn planted in the 26 counties in the Texas Panhandle and 6% of the total corn planted in the state of Texas. Extracts from the infected leaf tissue tested positive for Clavibacter michiganensis subsp. nebraskensis with a commercially available ELISA test (Neogen Inc., Scotland, UK). Isolation from the infected tissue onto CNS selective media (1) resulted in round, dark orange, mucoid colonies that tested gram positive with the Gram-stain test. BLAST nucleotide sequence alignments of the amplified 500-bp 16S rRNA region of the suspect culture's genome (2) revealed a 96% similarity for C. michiganensis subsp. nebraskensis (NCBI BLAST Accession No. U09381.1). To fulfill Koch's postulates, three sweet corn plants (Golden Cross Bantam) at growth stage V3 to V4 were inoculated in the greenhouse with a suspension of approximately 1 × 109 CFU/ml from suspect cultures grown on CNS for 5 days. Wounds approximately 6.5 cm long were created with sterile scissors on the fifth leaf from the bottom running parallel to the veins on either side of the midrib at the leaf apex. The leaf apex was dipped into 150 ml of the inoculum suspension for 5 s. Approximately 6 days after inoculation, discontinuous, water-soaked spots consistent with the symptoms on the original symptomatic leaves appeared on all the inoculated leaves near the site of infection. Colonies consistent with C. michiganensis subsp. nebraskensis (dark orange, mucoid) were reisolated onto CNS, completing Koch's postulates. To our knowledge, this is the first report of Goss's bacterial wilt and leaf blight on corn in Texas and because it is a residue-borne pathogen, the probability of it becoming a resident disease is relatively high. References: (1) D. C. Gross and A. K. Vidaver. Phytopathology 69:82, 1979. (2) X. Li and S. H. De Boer. 1995. Phytopathology 85:837, 1995.
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40

Szczepanek, Jan, Tomasz M. Kardas, and Yuriy Stepanenko. "Group Delay measurements of ultrabroadband pulses generated in highly nonlinear fibers." Photonics Letters of Poland 8, no. 4 (2016): 107. http://dx.doi.org/10.4302/plp.2016.4.06.

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Ultra broadband supercontinuum pulses are commonly used as a source of different wavelengths from a wide spectral bandwidth or as a source of very short pulses. However the processes responsible for wide spectral broadening are still under investigation. In this paper we examine the temporal and spectral characteristics of the pulses broadened upon propagation in the highly nonlinear photonics crystal fibers with different dispersion profiles. Generated supercontinuum pulses were experimentally characterized using cross-correlation frequency resolved optical gating technique. Full Text: PDF ReferencesM. Bradler, P. Baum, and E. Riedle, "Femtosecond continuum generation in bulk laser host materials with sub-?J pump pulses", Appl. Phys. B 97, 561 (2009). CrossRef T. M. Kardas, B. Ratajska-Gadomska, W. Gadomski, A. Lapini, and R. Righini, "The role of stimulated Raman scattering in supercontinuum generation in bulk diamond", Opt. Express 21, 24201 (2013). CrossRef A. Brodeur and S. L. Chin, "Band-Gap Dependence of the Ultrafast White-Light Continuum", Phys. Rev. Lett. 80, 4406 (1998). CrossRef R. R. Alfano, ed., The Supercontinuum Laser Source: Fundamentals with Updated References, 2nd ed (Springer, 2006). DirectLink A. L. Gaeta, Phys. "Catastrophic Collapse of Ultrashort Pulses", Rev. Lett. 84, 3582 (2000). CrossRef J. M. Dudley, G. Genty, and S. Coen, "Supercontinuum generation in photonic crystal fiber", Rev. Mod. Phys. 78, 1135 (2006). CrossRef M. Klimczak, B. Siwicki, P. Skibinski, D. Pysz, R. Stepien, A. Heidt, C. Radzewicz, and R. Buczynski, "Coherent supercontinuum generation up to 2.3 ?m in all-solid soft-glass photonic crystal fibers with flat all-normal dispersion", Opt. Express 22, 18824 (2014). CrossRef D. J. Kane and R. Trebino, "Characterization of arbitrary femtosecond pulses using frequency-resolved optical gating", IEEE J. Quantum Electron. 29, 571 (1993). CrossRef J. Dudley, X. Gu, L. Xu, M. Kimmel, E. Zeek, P. O'Shea, R. Trebino, S. Coen, and R. Windeler, "Cross-correlation frequency resolved optical gating analysis of broadband continuum generation in photonic crystal fiber: simulations and experiments", Opt. Express 10, 1215 (2002). CrossRef N. Nishizawa and T. Goto, "Experimental analysis of ultrashort pulse propagation in optical fibers around zero-dispersion region using cross-correlation frequency resolved optical gating", Opt. Express 8, 328 (2001). CrossRef X. Gu, L. Xu, M. Kimmel, E. Zeek, P. O'Shea, A. P. Shreenath, R. Trebino, and R. S. Windeler, "Frequency-resolved optical gating and single-shot spectral measurements reveal fine structure in microstructure-fiber continuum", Opt. Lett. 27, 1174 (2002). CrossRef S. Roy, S. K. Bhadra, and G. P. Agrawal, "Effects of higher-order dispersion on resonant dispersive waves emitted by solitons", Opt. Lett. 34, 2072?2074 (2009). CrossRef S. Bose, S. Roy, R. Chattopadhyay, M. Pal, and S. K. Bhadra, "Experimental and theoretical study of red-shifted solitonic resonant radiation in photonic crystal fibers and generation of radiation seeded Raman soliton", J. Opt. 17, 105506 (2015). CrossRef T. Roger, M. F. Saleh, S. Roy, F. Biancalana, C. Li, and D. Faccio, "High-energy, shock-front-assisted resonant radiation in the normal dispersion regime", Phys. Rev. A 88, (2013). CrossRef G. P. Agrawal, Nonlinear Fiber Optics, Fifth edition (Elsevier/Academic Press, 2013). DirectLink J. Szczepanek, T. Kardas, M. Nejbauer, C. Radzewicz, and Y. Stepanenko, "Simple all-PM-fiber laser system seeded by an all-normal-dispersion oscillator mode-locked with a nonlinear optical loop mirror", Proc. SPIE 9728, 972827 (2016). CrossRef C. Iaconis and I. A. Walmsley, "Self-referencing spectral interferometry for measuring ultrashort optical pulses", IEEE J. Quantum Electron. 35, 501 (1999). CrossRef L. E. Hooper, P. J. Mosley, A. C. Muir, W. J. Wadsworth, and J. C. Knight, "Coherent supercontinuum generation in photonic crystal fiber with all-normal group velocity dispersion", Opt. Express 19, 4902 (2011). CrossRef J. Szczepanek, T. M. Kardas, and Y. Stepanenko, "Sub-160-fs pulses dechriped to its Fourier transform limit generated from the all-normal dispersion fiber oscillator", Optical Society of America Frontiers in Optics conference, FTu3C?2 (2016). CrossRef G. Genty, M. Lehtonen, and H. Ludvigsen, "Effect of cross-phase modulation on supercontinuum generated in microstructured fibers with sub-30 fs pulses", Opt. Express 12, 4614 (2004). CrossRef S. Roy, S. K. Bhadra, K. Saitoh, M. Koshiba, and G. P. Agrawal, "Dynamics of Raman soliton during supercontinuum generation near the zero-dispersion wavelength of optical fibers", Opt. Express 19, 10443 (2011). CrossRef Y. Liu, Y. Zhao, J. Lyngso, S. You, W. L. Wilson, H. Tu, and S. A. Boppart, "Suppressing Short-Term Polarization Noise and Related Spectral Decoherence in All-Normal Dispersion Fiber Supercontinuum Generation", J. Light. Technol. 33, 1814 (2015). CrossRef
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41

Essefi, Elhoucine. "Homo Sapiens Sapiens Progressive Defaunation During The Great Acceleration: The Cli-Fi Apocalypse Hypothesis." International Journal of Toxicology and Toxicity Assessment 1, no. 1 (2021): 18–23. http://dx.doi.org/10.55124/ijt.v1i1.114.

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This paper is meant to study the apocalyptic scenario of the at the perspectives of the Great Acceleration. the apocalyptic scenario is not a pure imagination of the literature works. Instead, scientific evidences are in favour of dramatic change in the climatic conditions related to the climax of Man actions. the modelling of the future climate leads to horrible situations including intolerable temperatures, dryness, tornadoes, and noticeable sear level rise evading coastal regions. Going far from these scientific claims, Homo Sapiens Sapiens extended his imagination through the Climate-Fiction (cli-fi) to propose a dramatic end. Climate Fiction is developed into a recording machine containing every kind of fictions that depict environmental condition events and has consequently lost its true significance.
 Introduction
 The Great Acceleration may be considered as the Late Anthropocene in which Man actions reached their climax to lead to dramatic climatic changes paving the way for a possible apocalyptic scenario threatening the existence of the humanity. So, the apocalyptic scenario is not a pure imagination of the literature works. Instead, many scientific arguments especially related to climate change are in favour of the apocalypse1. As a matter of fact, the modelling of the future climate leads to horrible situations including intolerable temperatures (In 06/07/2021, Kuwait recorded the highest temperature of 53.2 °C), dryness, tornadoes, and noticeable sear level rise evading coastal regions. These conditions taking place during the Great Acceleration would have direct repercussions on the human species. Considering that the apocalyptic extinction had really caused the disappearance of many stronger species including dinosaurs, Homo Sapiens Sapiens extended his imagination though the Climate-Fiction (cli-fi) to propose a dramatic end due to severe climate conditions intolerable by the humankind. The mass extinction of animal species has occurred several times over the geological ages. Researchers have a poor understanding of the causes and processes of these major crises1. Nonetheless, whatever the cause of extinction, the apocalyptic scenario has always been present in the geological history. For example, dinosaurs extinction either by asteroids impact or climate changes could by no means denies the apocalyptic aspect2.At the same time as them, many animal and plant species became extinct, from marine or flying reptiles to marine plankton. This biological crisis of sixty-five million years ago is not the only one that the biosphere has suffered. It was preceded and followed by other crises which caused the extinction or the rarefaction of animal species. So, it is undeniable that many animal groups have disappeared. It is even on the changes of fauna that the geologists of the last century have based themselves to establish the scale of geological times, scale which is still used. But it is no less certain that the extinction processes, extremely complex, are far from being understood. We must first agree on the meaning of the word "extinction", namely on the apocalyptic aspect of the concept. It is quite understood that, without disappearances, the evolution of species could not have followed its course. Being aware that the apocalyptic extinction had massacred stronger species that had dominated the planet, Homo Sapiens Sapiens has been aware that the possibility of apocalyptic end at the perspective of the Anthropocene (i.e., Great Acceleration) could not be excluded. This conviction is motivated by the progressive defaunation in some regions3and the appearance of alien species in others related to change of mineralogy and geochemistry4 leading to a climate change during the Anthropocene. These scientific claims fed the vast imagination about climate change to set the so-called cli-fi. The concept of the Anthropocene is the new geological era which begins when the Man actions have reached a sufficient power to modify the geological processes and climatic cycles of the planet5. The Anthropocene by no means excludes the possibility of an apocalyptic horizon, namely in the perspectives of the Great Acceleration. On the contrary, two scenarios do indeed seem to dispute the future of the Anthropocene, with a dramatic cross-charge. The stories of the end of the world are as old as it is, as the world is the origin of these stories. However, these stories of the apocalypse have evolved over time and, since the beginning of the 19th century, they have been nourished particularly by science and its advances. These fictions have sometimes tried to pass themselves off as science. This is the current vogue, called collapsology6. This end is more than likely cli-fi driven7and it may cause the extinction of the many species including the Homo Sapiens Sapiens. In this vein, Anthropocene defaunation has become an ultimate reality8. More than one in eight birds, more than one in five mammals, more than one in four coniferous species, one in three amphibians are threatened. The hypothesis of a hierarchy within the living is induced by the error of believing that evolution goes from the simplest to the most sophisticated, from the inevitably stupid inferior to the superior endowed with an intelligence giving prerogative to all powers. Evolution goes in all directions and pursues no goal except the extension of life on Earth. Evolution certainly does not lead from bacteria to humans, preferably male and white. Our species is only a carrier of the DNA that precedes us and that will survive us. Until we show a deep respect for the biosphere particularly, and our planet in general, we will not become much, we will remain a predator among other predators, the fiercest of predators, the almighty craftsman of the Anthropocene. To be in the depths of our humanity, somehow giving back to the biosphere what we have taken from it seems obvious. To stop the sixth extinction of species, we must condemn our anthropocentrism and the anthropization of the territories that goes with it. The other forms of life also need to keep their ecological niches. According to the first, humanity seems at first to withdraw from the limits of the planet and ultimately succumb to them, with a loss of dramatic meaning. According to the second, from collapse to collapse, it is perhaps another humanity, having overcome its demons, that could come. Climate fiction is a literary sub-genre dealing with the theme of climate change, including global warming. The term appears to have been first used in 2008 by blogger and writer Dan Bloom. In October 2013, Angela Evancie, in a review of the novel Odds against Tomorrow, by Nathaniel Rich, wonders if climate change has created a new literary genre. Scientific basis of the apocalyptic scenario in the perspective of the Anthropocene
 Global warming
 All temperature indices are in favour of a global warming (Fig.1). According to the different scenarios of the IPCC9, the temperatures of the globe could increase by 2 °C to 5 °C by 2100. But some scientists warn about a possible runaway of the warming which can reach more than 3 °C. Thus, the average temperature on the surface of the globe has already increased by more than 1.1 °C since the pre-industrial era. The rise in average temperatures at the surface of the globe is the first expected and observed consequence of massive greenhouse gas emissions. However, meteorological surveys record positive temperature anomalies which are confirmed from year to year compared to the temperatures recorded since the middle of the 19th century. Climatologists point out that the past 30 years have seen the highest temperatures in the Northern Hemisphere for over 1,400 years. Several climatic centres around the world record, synthesize and follow the evolution of temperatures on Earth. Since the beginning of the 20th century (1906-2005), the average temperature at the surface of the globe has increased by 0.74 °C, but this progression has not been continuous since 1976, the increase has clearly accelerated, reaching 0.19 °C per decade according to model predictions. Despite the decline in solar activity, the period 1997-2006 is marked by an average positive anomaly of 0.53 °C in the northern hemisphere and 0.27 °C in the southern hemisphere, still compared to the normal calculated for 1961-1990. The ten hottest years on record are all after 1997. Worse, 14 of the 15 hottest years are in the 21st century, which has barely started. Thus, 2016 is the hottest year, followed closely by 2015, 2014 and 2010. The temperature of tropical waters increased by 1.2 °C during the 20th century (compared to 0.5 °C on average for the oceans), causing coral reefs to bleach in 1997.
 In 1998, the period of Fort El Niño, the prolonged warming of the water has destroyed half of the coral reefs of the Indian Ocean. In addition, the temperature in the tropics of the five ocean basins, where cyclones form, increased by 0.5 °C from 1970 to 2004, and powerful cyclones appeared in the North Atlantic in 2005, while they were more numerous in other parts of the world. Recently, mountains of studies focused on the possible scenario of climate change and the potential worldwide repercussions including hell temperatures and apocalyptic extreme events10 , 11, 12.
 Melting of continental glaciers
 As a direct result of the global warming, melting of continental glaciers has been recently noticed13. There are approximately 198,000 mountain glaciers in the world; they cover an area of approximately 726,000 km2. If they all melted, the sea level would rise by about 40 cm. Since the late 1960s, global snow cover has declined by around 10 to 15%. Winter cold spells in much of the northern half of the northern hemisphere are two weeks shorter than 100 years ago. Glaciers of mountains have been declining all over the world by an average of 50 m per decade for 150 years. However, they are also subject to strong multi-temporal variations which make forecasts on this point difficult according to some specialists. In the Alps, glaciers have been losing 1 meter per year for 30 years. Polar glaciers like those of Spitsbergen (about a hundred km from the North Pole) have been retreating since 1880, releasing large quantities of water. The Arctic has lost about 10% of its permanent ice cover every ten years since 1980. In this region, average temperatures have increased at twice the rate of elsewhere in the world in recent decades. The melting of the Arctic Sea ice has resulted in a loss of 15% of its surface area and 40% of its thickness since 1979. The record for melting arctic sea ice was set in 2017. All models predict the disappearance of the Arctic Sea ice in summer within a few decades, which will not be without consequences for the climate in Europe. The summer melting of arctic sea ice accelerated far beyond climate model predictions. Added to its direct repercussions of coastal regions flooding, melting of continental ice leads to radical climatic modifications in favour of the apocalyptic scenario.
 
 Fig.1 Evolution of temperature anomaly from 1880 to 2020: the apocalyptic scenario
 
 Sea level rise
 As a direct result of the melting of continental glaciers, sea level rise has been worldwide recorded14 ,15. The average level of the oceans has risen by 22 cm since 1880 and 2 cm since the year 2000 because of the melting of the glaciers but also with the thermal expansion of the water. In the 20th century, the sea level rose by around 2 mm per year. From 1990 to 2017, it reached the relatively constant rate of just over 3mm per year. Several sources contributed to sea level increase including thermal expansion of water (42%), melting of continental glaciers (21%), melting Greenland glaciers (15%) and melting Antarctic glaciers (8%). Since 2003, there has always been a rapid rise (around 3.3 mm / year) in sea level, but the contribution of thermal expansion has decreased (0.4 mm / year) while the melting of the polar caps and continental glaciers accelerates. Since most of the world’s population is living on coastal regions, sea level rise represents a real threat for the humanity, not excluding the apocalyptic scenario.
 Multiplication of extreme phenomena and climatic anomalies
 On a human scale, an average of 200 million people is affected by natural disasters each year and approximately 70,000 perish from them. Indeed, as evidenced by the annual reviews of disasters and climatic anomalies, we are witnessing significant warning signs. It is worth noting that these observations are dependent on meteorological survey systems that exist only in a limited number of countries with statistics that rarely go back beyond a century or a century and a half. In addition, scientists are struggling to represent the climatic variations of the last two thousand years which could serve as a reference in the projections. Therefore, the exceptional nature of this information must be qualified a little. Indeed, it is still difficult to know the return periods of climatic disasters in each region. But over the last century, the climate system has gone wild. Indeed, everything suggests that the climate is racing. Indeed, extreme events and disasters have become more frequent. For instance, less than 50 significant events were recorded per year over the period 1970-1985, while there have been around 120 events recorded since 1995.
 Drought has long been one of the most worrying environmental issues. But while African countries have been the main affected so far, the whole world is now facing increasingly frequent and prolonged droughts. Chile, India, Australia, United States, France and even Russia are all regions of the world suffering from the acceleration of the global drought. Droughts are slowly evolving natural hazards that can last from a few months to several decades and affect larger or smaller areas, whether they are small watersheds or areas of hundreds of thousands of square kilometres. In addition to their direct effects on water resources, agriculture and ecosystems, droughts can cause fires or heat waves. They also promote the proliferation of invasive species, creating environments with multiple risks, worsening the consequences on ecosystems and societies, and increasing their vulnerability. Although these are natural phenomena, there is a growing understanding of how humans have amplified the severity and impacts of droughts, both on the environment and on people. We influence meteorological droughts through our action on climate change, and we influence hydrological droughts through our management of water circulation and water processes at the local scale, for example by diverting rivers or modifying land use. During the Anthropocene (the present period when humans exert a dominant influence on climate and environment), droughts are closely linked to human activities, cultures, and responses. From this scientific overview, it may be concluded apocalyptic scenario is not only a literature genre inspired from the pure imagination. Instead, many scientific arguments are in favour of this dramatic destiny of Homo Sapiens Sapiens.
 
 Fig.2. Sea level rise from 1880 to 2020: a possible apocalyptic scenario (www.globalchange.gov, 2021)
 
 Apocalyptic genre in recent writing
 As the original landmark of apocalyptic writing, we must place the destruction of the Temple of Jerusalem in 587 BC and the Exile in Babylon. Occasion of a religious and cultural crossing with imprescriptible effects, the Exile brought about a true rebirth, characterized by the maintenance of the essential ethical, even cultural, of a national religion, that of Moses, kept as pure as possible on a foreign land and by the reinterpretation of this fundamental heritage by the archaic return of what was very old, both national traditions and neighbouring cultures. More precisely, it was the place and time for the rehabilitation of cultures and the melting pot for recasting ancient myths. This vast infatuation with Antiquity, remarkable even in the vocabulary used, was not limited to Israel: it even largely reflected a general trend. The long period that preceded throughout the 7th century BC and until 587, like that prior to the edict of Cyrus in 538 BC, was that of restorations and rebirths, of returns to distant sources and cultural crossings. In the biblical literature of this period, one is struck by the almost systematic link between, on the one hand, a very sustained mythical reinvestment even in form and, on the other, the frequent use of biblical archaisms. The example of Shadday, a word firmly rooted in the Semites of the Northwest and epithet of El in the oldest layers of the books of Genesis and Exodus, is most eloquent. This term reappears precisely at the time of the Exile as a designation of the divinity of the Patriarchs and of the God of Israel; Daily, ecological catastrophes now describe the normal state of societies exposed to "risks", in the sense that Ulrich Beck gives to this term: "the risk society is a society of catastrophe. The state of emergency threatens to become a normal state there1”. Now, the "threat" has become clearer, and catastrophic "exceptions" are proliferating as quickly as species are disappearing and climate change is accelerating. The relationship that we have with this worrying reality, to say the least, is twofold: on the one hand, we know very well what is happening to us; on the other hand, we fail to draw the appropriate theoretical and political consequences. This ecological duplicity is at the heart of what has come to be called the “Anthropocene”, a term coined at the dawn of the 21st century by Eugene Stoermer (an environmentalist) and Paul Crutzen (a specialist in the chemistry of the atmosphere) in order to describe an age when humanity would have become a "major geological force" capable of disrupting the climate and changing the terrestrial landscape from top to bottom. If the term “Anthropocene” takes note of human responsibility for climate change, this responsibility is immediately attributed to overpowering: strong as we are, we have “involuntarily” changed the climate for at least two hundred and fifty years. Therefore, let us deliberately change the face of the Earth, if necessary, install a solar shield in space. Recognition and denial fuel the signifying machine of the Anthropocene. And it is precisely what structures eco-apocalyptic cinema that this article aims to study. By "eco-apocalyptic cinema", we first mean a cinematographic sub-genre: eco-apocalyptic and post-eco-apocalyptic films base the possibility (or reality) of the end of the world on environmental grounds and not, for example, on damage caused by the possible collision of planet Earth with a comet. Post-apocalyptic science fiction (sometimes abbreviated as "post-apo" or "post-nuke") is a sub-genre of science fiction that depicts life after a disaster that destroyed civilization: nuclear war, collision with a meteorite, epidemic, economic or energy crisis, pandemic, alien invasion.
 Conclusion
 Climate and politics have been linked together since Aristotle. With Montesquieu, Ibn Khaldûn or Watsuji, a certain climatic determinism is attributed to the character of a nation. The break with modernity made the climate an object of scientific knowledge which, in the twentieth century, made it possible to document, despite the controversies, the climatic changes linked to industrialization. Both endanger the survival of human beings and ecosystems. Climate ethics are therefore looking for a new relationship with the biosphere or Gaia. For some, with the absence of political agreements, it is the beginning of inevitable catastrophes. For others, the Anthropocene, which henceforth merges human history with natural history, opens onto technical action. The debate between climate determinism and human freedom is revived. The reference to the biblical Apocalypse was present in the thinking of thinkers like Günther Anders, Karl Jaspers or Hans Jonas: the era of the atomic bomb would mark an entry into the time of the end, a time marked by the unprecedented human possibility of 'total war and annihilation of mankind. The Apocalypse will be very relevant in describing the chaos to come if our societies continue their mad race described as extra-activist, productivist and consumerist. In dialogue with different theologians and philosophers (such as Jacques Ellul), it is possible to unveil some spiritual, ethical, and political resources that the Apocalypse offers for thinking about History and human engagement in the Anthropocene. What can a theology of collapse mean at a time when negative signs and dead ends in the human situation multiply? What then is the place of man and of the cosmos in the Apocalypse according to Saint John? Could the end of history be a collapse? How can we live in the time we have left before the disaster? Answers to such questions remain unknown and no scientist can predict the trajectory of this Great Acceleration taking place at the Late Anthropocene.
 When science cannot give answers, Man tries to infer his destiny for the legend, religion and the fiction. Climate Fiction is developed into a recording machine containing every kind of fictions that depict environmental condition events and has consequently lost its true significance. Aware of the prospect of ecological collapse additionally as our apparent inability to avert it, we tend to face geology changes of forceful proportions that severely challenge our ability to imagine the implications. Climate fiction ought to be considered an important supplement to climate science, as a result, climate fiction makes visible and conceivable future modes of existence inside worlds not solely deemed seemingly by science, however that area unit scientifically anticipated. Hence, this chapter, as part of the book itself, aims to contribute to studies of ecocriticism, the environmental humanities, and literary and culture studies.
 
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 Akyol, Özlem. "Climate Change: An Apocalypse for Urban Space? An Ecocritical Reading of “Venice Drowned” and “The Tamarisk Hunter”." Folklor/Edebiyat 26, no. 101 (UluslararasıKıbrısÜniversitesi 2020): 115-126.
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 Wu, Jia, Zhenyu Han, Ying Xu, Botao Zhou, and Xuejie Gao. "Changes in extreme climate events in China under 1.5 C–4 C global warming targets: Projections using an ensemble of regional climate model simulations." Journal of Geophysical Research: Atmospheres 125, no. 2 (Wiley2020): e2019JD031057.https://doi.org/10.1029/2019JD031057
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 Wang, Lawrence K., Mu-Hao Sung Wang, Nai-Yi Wang, and Josephine O. Wong. "Effect of Global Warming and Climate Change on Glaciers and Salmons." In Integrated Natural Resources Management, ed.Lawrence K. Wang, Mu-Hao Sung Wang, Yung-Tse Hung, Nazih K. Shammas(Springer 2021), 1-36.
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Han, Shao-Qiang, Wen-Ping Song, Zhong-Hua Han, and Jian-Hua Xu. "Enhancing shock buffet predictions on a supercritical airfoil via high-order low-dissipation schemes." Physics of Fluids 37, no. 4 (2025). https://doi.org/10.1063/5.0257366.

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High-fidelity simulations of shock wave/boundary-layer interactions (SWBLI) require numerical methods with superior accuracy, resolution, and stability. This study incorporates optimized weighted essentially non-oscillatory (WENO-K) schemes into a finite difference solver on structured grids. The WENO-K schemes, with robust shock-capturing capabilities and adaptively optimized spectral properties, significantly improve unsteady Reynolds-averaged Navier–Stokes (URANS) simulations for SWBLI. Numerical simulations investigate unsteady shock buffet on the upper surface of a supercritical airfoil at Mach 0.73 and an angle of attack of 3.5°. The third-, fifth-, and seventh-order WENO-K schemes are employed to evaluate the influence of accuracy in convection flux discretization and numerical dissipation on shock buffet predictions. Results show excellent agreement with the experiment in predicting shock buffet frequency, as well as statistical pressure and velocity profiles. Notably, URANS simulations using WENO-K schemes outperform several published results obtained by URANS and hybrid URANS/LES (large eddy simulation) methods under comparable grid and time scales. The seventh-order WENO-K scheme effectively resolves intricate transient SWBLI flow features, including (1) periodic shock oscillations, (2) strong shear layers emanating from the shock, (3) separation bubble formation downstream of the shock, (4) wake vortex oscillations induced by the dynamic evolution of separation bubbles and shear layer instability, and (5) pressure wave propagation and feedback. These results highlight the importance of high-order, low-dissipation schemes in resolving the complex feedback mechanisms between shock waves, boundary layers, and wake dynamics. This study demonstrates that URANS method with high-order WENO-K schemes significantly enhances accuracy in predicting shock buffet in engineering.
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Grinin, Leonid. "Global technological perspectives in the light of cybernetic revolution and theory of long cycles." October 17, 2018. https://doi.org/10.5281/zenodo.3678297.

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In the present paper, on the basis of the theory of production principles and production revolutions, we reveal the interrelation between K-waves and major technological breakthroughs in history and make some predictions about features of the sixth Kondratieff wave in the light of the Cybernetic Revolution which, we think, started in the 1950s. We assume that the sixth K-wave in the 2030s and 2040s will merge with the final phase of the Cybernetic Revolution (which we call the phase of self-regulating systems). This period will be characterized by breakthroughs in medical technologies which will manage to combine many other technologies into a single complex of MBNRICtechnologies (med-bio-nano-robo-info-cognitive technologies). The article offers some predictions concerning the development of these technologies.
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Гринберг, Руслан, Ruslan Grinberg, Леонид Гринин, Leonid Grinin, Андрей Коротаев, and Andrey Korotaev. "Cyclic Economic Dynamics and Deflationary Phenomena: Analysis and Forecasts." Russian Foundation for Basic Research Journal. Humanities and social sciences, July 21, 2018, 48–62. http://dx.doi.org/10.22204/2587-8956-2018-091-02-48-62.

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The modern deflationary phenomena in the western and global economy are attributed to the fact that currently it is at the downward phase of the fifth long K-wave. Deflation has always been typical for the depressive periods in economy; presently it also manifests itself as the world economy has turned global, yet it lacks any control mechanisms. The authors suppose that a new economic crisis will break out in the western economy in the second half of 2018–2019 and that the depressive and deflationary trends will continue for another number of years.
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45

Mansour, Marwa, and Islam Mansour. "Battery‐free ultra‐low‐power radio‐frequency receiver for mm‐wave applications using 130‐nm CMOS technology with harvested DC supplies." International Journal of Circuit Theory and Applications, May 24, 2024. http://dx.doi.org/10.1002/cta.4101.

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SummaryThis paper presents a battery‐free ultra‐low‐power (ULP), highly integrated, and wide‐bandwidth low‐IF radio‐frequency (RF) receiver designed for millimeter‐wave (mm‐Wave) applications, utilizing 130‐nm CMOS technology. The suggested RF receiver is suitable for K‐band (n258) at 26 GHz, Ka‐band (n261 and n257) at 28 GHz, and the LMDS band at 28 GHz in fifth‐generation applications. The proposed radio receiver consists of a low‐noise driver stage implemented using a complementary current‐reuse common gate with an active shunt feedback configuration and an in‐phase/quadrature‐phase (I/Q) demodulator. The proposed RF receiver employs transformer coupling to isolate the DC path between the transconductance stage (RF stage) and the switching stage (IF stage). The driver stage expands the RF input impedance while maintaining acceptable linearity and gain with ultra‐low DC power dissipation. The DC supplies for the proposed mm‐Wave RF receiver are generated using two novel energy‐harvesting voltage doubler circuits to provide positive and negative voltages. The proposed mm‐Wave radio receiver consumes 0.475 mW from a 1.1 V DC supply and exhibits a power conversion gain (CG) of 6.3 dB, with a 3 dB frequency bandwidth extending from 22 to 32 GHz. The input 1‐dB compression point (P1dB) of the RF receiver is −2.65 dBm, and the input third‐order intercept point (IIP3) is 7.35 dBm. With a sensitivity of −66.5 dBm at a 100 MHz channel bandwidth and a dynamic range of 63.85 dB, the suggested receiver demonstrates notable performance characteristics. The proposed radio receiver boasts an excellent figure of merit (FoM) at 215 dB, surpassing published works by a margin of 8–31 dB. The primary positive supply voltage is derived from a double‐band positive voltage doubler with series resonance feedback and parallel resonance networks, efficiently achieving the desired DC voltage and output current (1.1 V and 450 μA). Meanwhile, the negative gate bias is provided by a negative voltage doubler, ensuring the necessary negative voltage (−0.5 V) without any current conditions.
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Yu, Peng, Ruigeng Hu, Jike Zhang, et al. "Numerical study on local scour characteristics around submarine pipelines in the Yellow River Delta silty sandy soil under waves and currents." Deep Underground Science and Engineering, February 19, 2024. http://dx.doi.org/10.1002/dug2.12068.

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AbstractDue to their high reliability and cost‐efficiency, submarine pipelines are widely used in offshore oil and gas resource engineering. Due to the interaction of waves, currents, seabed, and pipeline structures, the soil around submarine pipelines is prone to local scour, severely affecting their operational safety. With the Yellow River Delta as the research area and based on the renormalized group (RNG) k‐ε turbulence model and Stokes fifth‐order wave theory, this study solves the Navier–Stokes (N–S) equation using the finite difference method. The volume of fluid (VOF) method is used to describe the fluid‐free surface, and a three‐dimensional numerical model of currents and waves–submarine pipeline–silty sandy seabed is established. The rationality of the numerical model is verified using a self‐built waveflow flume. On this basis, in this study, the local scour development and characteristics of submarine pipelines in the Yellow River Delta silty sandy seabed in the prototype environment are explored and the influence of the presence of pipelines on hydrodynamic features such as surrounding flow field, shear stress, and turbulence intensity is analyzed. The results indicate that (1) local scour around submarine pipelines can be divided into three stages: rapid scour, slow scour, and stable scour. The maximum scour depth occurs directly below the pipeline, and the shape of the scour pits is asymmetric. (2) As the water depth decreases and the pipeline suspension height increases, the scour becomes more intense. (3) When currents go through a pipeline, a clear stagnation point is formed in front of the pipeline, and the flow velocity is positively correlated with the depth of scour. This study can provide a valuable reference for the protection of submarine pipelines in this area.
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Sun Bei-Bei, Ye Wen-Hua, and Zhang Wei-Yan. "Richtmyer-Meshkov-like instability of the density perturbation and its coupling to the unperturbed interface." Acta Physica Sinica, 2023, 0. http://dx.doi.org/10.7498/aps.72.20230928.

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The interaction between the shock and the internal density perturbation of the target material produces an RM-like instability, which couples to the ablation front and generates instability seeds. Recent studies have demonstrated the significance of internal material density perturbations on implosion performance. This paper presents a two-dimensional numerical investigation of the growth of the RM-like instability in linear region and its coupling mechanism with the interface. The Euler equations in two dimensions are solved in Cartesian coordinates using the fifth-order WENO scheme in space and the two-step Runge-Kutta scheme in time. The computational domain has a length of 200 <i>um</i> in the <i>x</i>-direction and <i>λ<sub>y</sub></i> in the <i>y</i>-direction. The numerical resolution adopted in this paper is Δ<sub><i>x</i></sub>=Δ<sub><i>y</i></sub>=<i>λ<sub>y</sub></i>/128. A periodic boundary condition is used in the <i>y</i>-direction, while an outflow boundary condition is used in the <i>x</i>-direction. The interaction between shock and density perturbations will deposit vorticity in the density perturbation region. The width of the density perturbation region can be represented by the width of the vortex pair. The growth rate of the RM-like instability can be represented by the growth rate of the width of the density-disturbed region or the maximum perturbation velocity in the <i>y</i>-direction. The simulation results show that the growth rate of the vortex pair width is proportional to the perturbation wave number <i>k<sub>y</sub></i>, the perturbation amplitude <i>η</i>, and the velocity difference before and after the shock wave Δ<i>u</i>, in another word <i>δv</i>∝<i>k<sub>y</sub></i>Δ<i>uη</i>. In the problem of coupling the RM-like instability to the interface, we calculate the derivation of the interface perturbation amplitude with respect to time to obtain the growth rate of the interface. It is concluded from the simulations that the coupling of the RM-like instability to the interface has two mechanisms: acoustic coupling and vortex merging. When the density perturbation region is far away from the interface, only acoustic waves are coupled to the interface. The dimensionless growth rate of interface perturbation caused by acoustic coupling decays exponentially with <i>k<sub>y</sub>L</i>, δ<i>v<sub>i</sub></i>/( <i>k<sub>y</sub></i>Δ<i>u</i><i>η</i>)∝<${e^{ - {k_y}L}}$. When the density perturbation region is closer to the interface, acoustic coupling and vortex merging work together. The vortex merging leads to an increase in the perturbation velocity when the Atwood number of the interface is positive. When the Atwood number is positive, reducing the Atwood number on the interface and increasing the width of the transition layer on the interface can both reduce the growth of interface perturbation caused by the RM-like instability coupling.
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Guinat, Claire, Gaëlle Nicolas, Timothée Vergne, et al. "Spatio-temporal patterns of highly pathogenic avian influenza virus subtype H5N8 spread, France, 2016 to 2017." Eurosurveillance 23, no. 26 (2018). http://dx.doi.org/10.2807/1560-7917.es.2018.23.26.1700791.

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Introduction France is one of Europe’s foremost poultry producers and the world’s fifth largest producer of poultry meat. In November 2016, highly pathogenic avian influenza (HPAI) virus subtype H5N8 emerged in poultry in the country. As of 23 March 2017, a total of 484 confirmed outbreaks were reported, with consequences on animal health and socio-economic impacts for producers. Methods: We examined the spatio-temporal distribution of outbreaks that occurred in France between November 2016 and March 2017, using the space–time K-function and space–time permutation model of the scan statistic test. Results: Most outbreaks affected duck flocks in south-west France. A significant space–time interaction of outbreaks was present at the beginning of the epidemic within a window of 8 km and 13 days. This interaction disappeared towards the epidemic end. Five spatio-temporal outbreak clusters were identified in the main poultry producing areas, moving sequentially from east to west. The average spread rate of the epidemic front wave was estimated to be 5.5 km/week. It increased from February 2017 and was negatively associated with the duck holding density. Conclusion: HPAI-H5N8 infections varied over time and space in France. Intense transmission events occurred at the early stages of the epidemic, followed by long-range jumps in the disease spread towards its end. Findings support strict control strategies in poultry production as well as the maintenance of high biosecurity standards for poultry holdings. Factors and mechanisms driving HPAI spread need to be further investigated.
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Nafea, Safa N., and Nasser N. Khamiss. "High – gain and wide – bandwidth patch antenna for fifth generation communication applications at K – Band." International Journal of Electronics and Telecommunications, April 7, 2025, 209–14. https://doi.org/10.24425/ijet.2025.153564.

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The patch antenna usually used for many wireless applications, and fifth generation (5G) is the most attracting application in the field of millimeter wave communications recently. The researchers worked on solving problems those considered milestones against using patch antenna for 5G applications such as being an antenna with moderate gain and narrow operating bandwidth with high side lobe levels. In this article a microstrip patch antenna had been presented to operate over the n258 – Band for 5G communications at 26 GHz with an operating bandwidth around than 7 GHz. The proposed antenna was printed on Rogers RT/Duroid 5880 substrate. A high gain of 8.10 dB had been achieved with high Front – to – Back ratio of 24.47 dB and very low side lobe levels far field radiation pattern around -17 dB. The proposed antenna covered the operating bandwidth n258 for fifth generation applications in range of (24.25 – 27.50) GHz. The Computer simulation Technology (CST) had been used as a simulation environment for this design.
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50

Vega-González, L. R. "Innovation rate of change measurement part 1: Information Technology (IT)." Journal of Applied Research and Technology 3, no. 03 (2005). http://dx.doi.org/10.22201/icat.16656423.2005.3.03.560.

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Abstract:
It is possible to characterize the different stages of history according the type of technology available. The last fifty years of human history have been referred to as “The Information Age" because of the great advancements and innovations of technology in electronics, computers and communications. The first part of this work presents a method based on the generation and exploitation of a database for the measurement of information technology gradients. The lack of the innovative data in earlier historic times is compensated by the consideration of the transport technologies as IT. The obtained result is a clear exponential growth curve. If the IT is driver of the global change, the notorious changes in the resulting graph can be related to the appearance of the Kondrattief cycles or "K" waves. Modelski [48] pointed out that the evolution of economic processes is closely related to the rate of growth in technological learning. According to the obtained results, the expected rate of change for IT innovation during the first two decades of the XXI Century will surely surpass the rate of change of technological learning. This will probably generate a non-sustainable system unless a change in the human consciousness occurs. Apparently, the sustainable evolution of the world system will depend on the appropriate technological selections, provoking the adjustment of innovation gradients to the rates of technological learning within the next generational cycles.
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