bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hybrid evolutionary algorithm in the optimization problem of the shooting system parameters
Authors: Demidova L A , Petrova N A 
Published: January 2021

Abstract
The optimization problem of the shooting system parameters values by means of the hybrid evolutionary algorithm has been considered. The idea of hybridization of the genetic algorithm and differential evolution algorithm to solve the problem of optimizing the coverage of the observed object by the shooting system has been proposed and implemented. The results of solving the optimization problem of the shooting system parameters, confirming the feasibility application of the proposed hybrid evolutionary algorithm which provides minimization of time spent on solving the optimization problem has been described.
The predictive display as a means of suppressing the negative effects of wake vortex encounters
Authors: Efremov A V , Tiaglik M S , Voronka T V 
Published: January 2021

Abstract
The research develops a predictive information display system as a means of suppressing the negative effects of wake vortex encounters by aircraft during the landing phase. A mathematical model of aircraft interaction with a wake vortex is developed, with the effectiveness of the predictive information indication being evaluated via studies using a flight simulator.
Digital recruitment of innovative project teams’ leaders based on genetic algorithms
Authors: Kovshov E E , Kuvshinnikov V S , Osipenko L E 
Published: January 2021

Abstract
Over the past decade, innovation has become an important part of the development for large business companies. The search for promising topics, as well as the recruitment of potential applicants teams who can implement an innovative project with the maximum benefit for business at the lowest cost, led to the search for approaches to solving these problems using IT. Since the problems of such research are covered separately in different industry areas, we implemented an approach to completing project teams based on genetic algorithms. A wide review of the literature allowed us to identify some important characteristics of innovative projects, as well as to summarize the portfolio of competencies required for potential designers. These attributive characteristics of the project and the applicants’ competence should be taken into account. The developed genetic algorithm allows searching for multiple parameters simultaneously and generating new solutions through the use of different operators. The results open up a new range of opportunities for business companies and government organizations interested in successful implementation of innovations.
Development of the mathematical model of catalytic oxidation-reduction reaction kinetics for wastewater treatment technology using vortex layer devices
Authors: Lukashev P E , Sidorov M I , Stavrovskiy M E , Lazarev S A , Ragutkin A V , Korolev E I , Sh Gazanova N 
Published: January 2021

Abstract
The article considers the mechanisms of intensifying chemical reactions occurring in vortex layer devices. The competition of reagents used as oxidizing agents in water treatment and oxidizing agents appearing during the operation of vortex layer devices is considered. The article offers a description of wastewater treatment process kinetics both for the oxidizing process and the process caused by electrochemical (corrosive) synthesis of highly active reducing agents. The mathematical model is constructed and its analysis is given.
Hydraulic losses optimization methods used in air conditioning system valve design for different closure angles
Authors: Napreenko K S , Lamtyugina A V 
Published: January 2021

Abstract
This article describes methods for determining the hydraulic resistances of A/C system units. The advantages of computational hydrodynamics over the traditional method of calculation using the coefficient of hydraulic resistance are shown. A “step-by-step” example of calculating the hydraulic resistance of an A/C system unit in the ANSYS CFX software package is given (converting 3D geometry into a calculation model; selecting, configuring, and building a mesh model; configuring calculation parameters, including boundary conditions, turbulence models, and calculation stop criteria; calculating and processing results). Special attention is paid to the consideration of the SST turbulence model. The calculation results show the distribution fields of total and static pressure, velocity, and flow lines at discrete rotation angles. Graphically, the dependence of the drop in hydraulic resistance on the increase in the area of the flow section of the damper is shown. Hydraulic losses are also determined when the pressure increases. Conclusions are made about the application of the calculation results in creating a comprehensive model of the system
Control synthesis for tasks with a given output function decentralized SISO-systems
Authors: Nikulchev E 
Published: January 2021

Abstract
For the control synthesis of multiply connected objects with many inputs and many outputs (MIMO) by importance of reducing computational costs by reducing accuracy, the method of decentralized control is used by dividing the original system into systems with one input and one output (SISO). The paper proposes an approach to the control synthesis of a decentralized SISO system, which is a part of a multi-connected MIMO object in conditions of impossibility of identifying model parameters. The paper considers the problem of control synthesis, which provides a given desired form of the output process.
Adaptive imaging system for electromagnetic scattering field of aircraft
Authors: Tarlanov A T , Kurbanismailov Z M 
Published: January 2021

Abstract
Electromagnetic compatibility (EMS) of a sophisticated aircraft technical system with other systems is a prerequisite for their sustainable operation. Aerospace technology, where both highly sensitive measurements and energetic control effects are closely combined in the dense layout of an aircraft, requires a solution to the EMS problem. This paper shows the need for effective technology to control the electromagnetic radiation created in the surrounding space, both by subsystems of aircraft and by the whole object. The method how to of visualize of 3D electromagnetic field both in space and in time is considered.
Valve-based consecutive bioprinting method for multimaterial tissue-like constructs with controllable interfaces
Authors: Wang Heran , Guo Kai , Zhang Liming , Zhu Huixuan , Li Shijie , Li Song , Gao Feiyang , Liu Xin , Gu Qi , Liu Lianqing , Zheng Xiongfei 
Published: January 2021

Abstract
Bioprinting is a promising technology focusing on tissue manufacturing, whose vital problem is the precise assembly of multiple materials. As the primary solution, the extrusion-based multi-printhead bioprinting (MPB) method requires printhead switching during the printing process, which induces inefficient motion time and material interface defects. We present a valve-based consecutive bioprinting (VCB) method to resolve these problems, containing a precise integrated switching printhead and a well-matched voxelated digital model. The rotary valve built-in the VCB printhead guarantees the precise assembling of different materials at the interface isolated from the viscoelastic inks’ elastic potential energy in the cartridge. We study the coordinated control approach of the valve rotation and pressure adjustment to achieve the seamless switching, leading to a controllable multimaterial interface, including boundary and suture structure. Furthermore, we compare the VCB method and MPB method, quantitatively and comprehensively, indicating that the VCB method obtained greater mechanical strength (maximum tensile deformation increased by 44.37%) and higher printing efficiency (effective time ratio increased by 29.48%). As an exemplar, we fabricate a muscle-like tissue with a vascular tree, suture interface encapsulating C2C12, and human dermal fibroblasts (HDFB) cells, then placed it in complete medium with continuous perfusion for 5 d. Our study suggests that the VCB method is sufficient to fabricate heterogeneous tissues with complex multimaterial interfaces.
Alginate–gelatin–Matrigel hydrogels enable the development and multigenerational passaging of patient-derived 3D bioprinted cancer spheroid models
Authors: Flores-Torres Salvador , Peza-Chavez Omar , Kuasne Hellen , Munguia-Lopez Jose G , Kort-Mascort Jacqueline , Ferri Lorenzo , Jiang Tao , Rajadurai Charles V , Park Morag , Sangwan Veena , Kinsella Joseph M 
Published: January 2021

Abstract
Hydrogels consisting of controlled fractions of alginate, gelatin, and Matrigel enable the development of patient-derived bioprinted tissue models that support cancer spheroid growth and expansion. These engineered models can be dissociated to be then reintroduced to new hydrogel solutions and subsequently reprinted to generate multigenerational models. The process of harvesting cells from 3D bioprinted models is possible by chelating the ions that crosslink alginate, causing the gel to weaken. Inclusion of the gelatin and Matrigel fractions to the hydrogel increases the bioactivity by providing cell-matrix binding sites and promoting cross-talk between cancer cells and their microenvironment. Here we show that immortalized triple-negative breast cancer cells (MDA-MB-231) and patient-derived gastric adenocarcinoma cells can be reprinted for at least three 21 d culture cycles following bioprinting in the alginate/gelatin/Matrigel hydrogels. Our drug testing results suggest that our 3D bioprinted model can also be used to recapitulate in vivo patient drug response. Furthermore, our results show that iterative bioprinting techniques coupled with alginate biomaterials can be used to maintain and expand patient-derived cancer spheroid cultures for extended periods without compromising cell viability, altering division rates, or disrupting cancer spheroid formation.
High throughput microfluidic system with multiple oxygen levels for the study of hypoxia in tumor spheroids
Authors: Berger Fridman Ilana , Ugolini Giovanni Stefano , VanDelinder Virginia , Cohen Smadar , Konry Tania 
Published: January 2021

Abstract
Replication of physiological oxygen levels is fundamental for modeling human physiology and pathology in in vitro models. Environmental oxygen levels, applied in most in vitro models, poorly imitate the oxygen conditions cells experience in vivo, where oxygen levels average ∼5%. Most solid tumors exhibit regions of hypoxic levels, promoting tumor progression and resistance to therapy. Though this phenomenon offers a specific target for cancer therapy, appropriate in vitro platforms are still lacking. Microfluidic models offer advanced spatio-temporal control of physico-chemical parameters. However, most of the systems described to date control a single oxygen level per chip, thus offering limited experimental throughput. Here, we developed a multi-layer microfluidic device coupling the high throughput generation of 3D tumor spheroids with a linear gradient of five oxygen levels, thus enabling multiple conditions and hundreds of replicates on a single chip. We showed how the applied oxygen gradient affects the generation of reactive oxygen species (ROS) and the cytotoxicity of Doxorubicin and Tirapazamine in breast tumor spheroids. Our results aligned with previous reports of increased ROS production under hypoxia and provide new insights on drug cytotoxicity levels that are closer to previously reported in vivo findings, demonstrating the predictive potential of our system.
Robust higher-order optical vortices for information transmission in twisted anisotropic optical fibers
Authors: Barshak E V , Vikulin D V , Lapin B P , Alieva S S , Alexeyev C N , Yavorsky M A 
Published: January 2021

Abstract
We study the propagation of light in twisted anisotropic fibers by obtaining the analytical expressions and propagation constants for higher-order modes with the azimuthal number

|

ℓ

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1

. It is shown that for arbitrary fiber parameters, the modes are elliptically polarized optical vortices of well-defined orbital angular momentum. We reveal the phenomena of orbital birefringence and the optical Zeeman effect for the higher-order topologically charged fiber modes. Finally, circularly and linearly polarized optical vortices are demonstrated to be modes that are robust against small constant and spatially varying perturbations of both fiber material and form anisotropy; this robustness is due to the effects of the spin–orbit interaction and/or torsional-stress-induced orbital birefringence.
Bi-Ronchi-test proposal for wavefront sensing and aberration analysis based on the differential form of the Zernike polynomials
Authors: Arriaga Hernández J A , Cuevas Otahola B T , Jaramillo Núñez A , Oliveros Oliveros J , Morín Castillo M 
Published: January 2021

Abstract
In this work, we show a proposal involving differential and vectorial equations to obtain the scalar surface of a wavefront (W) and the transversal aberration (TA) from the Bi-Ronchi test (BRT). The execution and computation times of this technique are significantly lower than those corresponding to the Ronchi test (RT). Moreover, it provides wavefront results along the axes X and Y by using bi-Ronchi ruling (bRR) with periods in XY. In the case of mirrors, this technique provides complete information of the whole surface along XY from a single test, with the potential to be applied in the other optical elements to measure their wavefronts. Hence, we propose the construction of square meshes, bRR type meshes, using Al and Au atomic depositions in glass substrates with different periods in XY, allowing us to observe bi-Ronchigrams. The captures of Bironchigrams enabled us to perform the analysis of the transversal aberrations in terms of the Zernike polynomials described by circular polynomials and an angular function with respect to the azimuthal term. We build a matrix solution from the vectors used to identify the centroids in the bi-Ronchigram higher-intensity zones, also considering the Rayces’ equations from which the wavefront and the transversal aberrations are simultaneously obtained. We discuss and compare our results with the RT. Finally, we highlight an additional result related to the proposed technique, involving the contention of the Ronchigram in the Bi-Ronchigram, resembling the case where the BRT contains the RT.
Comment on: The effect of Li4Ti5O12 nanoparticles on structural, linear and third order nonlinear optical properties of PVDF films (Mater. Res. Express (2019)
6 085312)
Authors: Sahebi Ramezan 
Published: January 2021

Abstract
In a recent paper [Mater. Res. Express (2019) 6 085312] El-Metwally et al studied the structural and optical properties of PVDF films doped with Li4Ti5O12 nanoparticles. The authors have used a wrong approach to calculate the reflectance spectra. The wrong obtained values of reflectance were used to calculate the refractive index. Consequently, other reported optical parameters in the commented paper that are calculated based on the refractive index such as optical conductivity, real and imaginary parts of the optical dielectric constant, the dispersion parameters evaluated from Wemple-DiDomenico single oscillator model, high-frequency dielectric constant, plasma oscillation frequency, linear optical susceptibility, third-order nonlinear optical susceptibility and the nonlinear refractive index are incorrect.
Eco-friendly approach for preparation of water-based superhydrophobic silica aerogels via ambient pressure drying
Authors: Yuan Xiaoling , Xu Lihui , Pan Hong , Shen Yong , Wang Liming , Xie Mingrui 
Published: January 2021

Abstract
In this work, superhydrophobic methyltrimethoxysilane (MTMS)-based silica aerogels were fabricated via water-based sol–gel reaction by ambient pressure drying (APD) method in the presence of surfactant. The structure, morphology, and hydrophobic properties of the obtained silica aerogel were characterized by scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) methods, X-ray diffractometer (XRD), and water contact angle measurement. The effects of the concentration of MTMS, the pH value of the solution, and the amount of surfactant cetyltrimethylammonium bromide (CTAB) on properties of silica aerogels were investigated, respectively. Increasing the concentration of MTMS to a great extent resulted in higher density and lower porosity of silica aerogel. Alkali catalyst was an extremely crucial factor for preparing silica aerogels. With the increase of the pH value from 7.5 to 10 the gelation time of the prepared aerogels was observed to decrease from 40 min to 2 min, and the shrinkage of aerogel sample decreased from 15.5% to 3.5%. The skeleton structure of the prepared silica aerogel gradually transformed from coarsened spherical to continuous irregularity finer structures with the increased concentration of CTAB. In addition, the prepared silica aerogel showed outstanding anti-adhesion property and superhydrophobic ability with a water contact angle (WCA) of 160.6 ± 1.3°.
Effect of temperature on corrosion behavior of E690 steel in 3.5 wt.% NaCl solution
Authors: Yan Qi , Yin Qun , Cui Jie , Wang Xinyi , Qiao Yanxin , Zhou Huiling 
Published: January 2021

AbstractThe corrosion behavior of E690 steel in 3.5 wt.% NaCl solution at temperatures from 20 °C to 60 °C was investigated using electrochemical test. The corrosion morphology was characterized using SEM and AFM, and the corrosion layer was characterized using EDS, Raman spectroscopy and XPS. The results showed that the corrosion rate of E690 steel improves with the increase in temperature. The corrosion layers of E690 steel are mainly composed ofα-Fe2O3,α-FeOOH andγ-FeOOH. With the elevated temperature, the content ofα-FeOOH in corrosion layers increases, while the content ofα-Fe2O3andγ-FeOOH decreases. The corrosion mechanisms were briefly discussed.
Distributed deep reinforcement learning for simulation control
Authors: Pawar Suraj , Maulik Romit 
Published: January 2021

Abstract
Several applications in the scientific simulation of physical systems can be formulated as control/optimization problems. The computational models for such systems generally contain hyperparameters, which control solution fidelity and computational expense. The tuning of these parameters is non-trivial and the general approach is to manually ‘spot-check’ for good combinations. This is because optimal hyperparameter configuration search becomes intractable when the parameter space is large and when they may vary dynamically. To address this issue, we present a framework based on deep reinforcement learning (RL) to train a deep neural network agent that controls a model solve by varying parameters dynamically. First, we validate our RL framework for the problem of controlling chaos in chaotic systems by dynamically changing the parameters of the system. Subsequently, we illustrate the capabilities of our framework for accelerating the convergence of a steady-state computational fluid dynamics solver by automatically adjusting the relaxation factors of the discretized Navier–Stokes equations during run-time. The results indicate that the run-time control of the relaxation factors by the learned policy leads to a significant reduction in the number of iterations for convergence compared to the random selection of the relaxation factors. Our results point to potential benefits for learning adaptive hyperparameter learning strategies across different geometries and boundary conditions with implications for reduced computational campaign expenses
4

4
Data and codes available at https://github.com/Romit-Maulik/PAR-RL.
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Synthesis, characterization and bioactivity of thio-acetamide modified ZnO nanoparticles embedded in zinc acetate matrix
Authors: Panigrahi U K , Sahu B , Behuria H G , Sahu S K , Dhal S P , Hussain Shamima , Mallick P 
Published: January 2021

Abstract
ZnO nanoparticles embedded in zinc acetate matrix were synthesized by chemical route. The effect of thio-acetamide concentration during its synthesis was probed by structural, morphological, optical and bioactivity studies. XRD characterization indicated the formation of dominant phase of zinc acetate along with the low intensity peak of wurtzite ZnO. Morphological transition from bulky-like feature to flower-like feature via flake-like feature, is evidenced with increasing thio-acetamide molar concentrations. The optical band gap of samples decreased from ∼3.29 to 3.24 eV whereas the emitted color shifted from near green to blue region with increasing of molar concentration of thio-acetamide from 0 to 30% in the sample. The nanoparticles exhibited antimicrobial activity against seven (7) common human pathogenic bacteria including drug resistant varieties K. pneumonaie and S. aureus. The nanoparticles formed pores in the biological model membranes made from egg-phosphatidyl choline. Our study reveals that the thio-acetamide modified ZnO nanoparticles embedded in zinc acetate matrix could be used as potential drug lead to fight drug resistance against K. pneumoniae and S. aureus.
A classification tree to assist with routine scoring of the Clinical Frailty Scale
Authors: Theou Olga , Pérez-Zepeda Mario Ulises , van der Valk Alexandra M , Searle Samuel D , Howlett Susan E , Rockwood Kenneth 
Published: January 2021

Abstract

Background
the Clinical Frailty Scale (CFS) was originally developed to summarise a Comprehensive Geriatric Assessment and yield a care plan. Especially since COVID-19, the CFS is being used widely by health care professionals without training in frailty care as a resource allocation tool and for care rationing. CFS scoring by inexperienced raters might not always reflect expert judgement. For these raters, we developed a new classification tree to assist with routine CFS scoring. Here, we test that tree against clinical scoring.

Objective/Methods
we examined agreement between the CFS classification tree and CFS scoring by novice raters (clerks/residents), and the CFS classification tree and CFS scoring by experienced raters (geriatricians) in 115 older adults (mean age 78.0 ± 7.3; 47% females) from a single centre.

Results
the intraclass correlation coefficient (ICC) for the CFS classification tree was 0.833 (95% CI: 0.768–0.882) when compared with the geriatricians’ CFS scoring. In 93%, the classification tree rating was the same or differed by at most one level with the expert geriatrician ratings. The ICC was 0.805 (0.685–0.883) when CFS scores from the classification tree were compared with the clerk/resident scores; 88.5% of the ratings were the same or ±1 level.

Conclusions
a classification tree for scoring the CFS can help with reliable scoring by relatively inexperienced raters. Though an incomplete remedy, a classification tree is a useful support to decision-making and could be used to aid routine scoring of the CFS.