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Pre-trained Mol2Vec Embeddings as a Tool for Predicting Polymer Properties

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Chinese Journal of Polymer Science 2024年第12期42卷 2059-2068,I0014页

作者： ivan Zlobin Nikita Toroptsev Gleb Averochkin Alexander Pavlov Center NTI“Digital Materials Science:New Materials and Substances” Bauman Moscow State Technical University2S1 Baumanskaya St.5/1105005MoscowRussia A.N.Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences Vavilova St.28Bld.1119334MoscowRussia

Machine learning-assisted prediction of polymer properties prior to synthesis has the potential to significantly accelerate the discovery and development of new polymer *** date,several approaches have been implemented to represent the chemical structure in machine learning models,among which Mol2Vec embeddings have attracted considerable attention in the cheminformatics community since their introduction in ***,for small datasets,the use of chemical structure representations typically increases the dimensionality of the input dataset,resulting in a decrease in model ***,the limited diversity of polymer chemical structures hinders the training of reliable embeddings,necessitating complex task-specific architecture *** address these challenges,we examined the efficacy of Mol2Vec pre-trained embeddings in deriving vectorized representations of *** study assesses the impact of incorporating Mol2Vec compound vectors into the input features on the efficacy of a model reliant on the physical properties of 214 *** results will hopefully highlight the potential for improving prediction accuracy in polymer studies by incorporating pre-trained embeddings or promote their utilization when dealing with modestly sized polymer databases.

关键词： Properties prediction High dimensional embeddings Machine learning Mol2Vec

COVID-19 and Ecosyndemic Vulnerability: Implications for El Niño-Sensitive Countries in Latin America

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International Journal of Disaster Risk Science 2021年第1期12卷 147-156页

作者： ivan J.Ramírez Jieun Lee Department of Health and Behavioral Sciences University of Colorado DenverDenverCO 80217USA Consortium for Capacity Building Institute of Arctic and Alpine Research(INSTAAR)University of Colorado BoulderBoulderCO 80308USA Department of Geography GISand SustainabilityUniversity of Northern ColoradoGreeleyCO 80639USA

Latin America has emerged as an epicenter of the COVID-19 ***,Peru,and Ecuador report some of the highest COVID-19 rates of incidence and deaths in the *** countries also face synergistic threats from multiple infectious diseases(that is,ecosyndemic)and quasi-periodic El Niño-related hazards every few *** example,Peru,which is highly sensitive to El Niño,already copes with an ecosyndemic health burden that heightens during and following weather and climate extreme *** an ecosyndemic lens,which draws on a multi-disease hazard context of place,this commentary highlights the importance of El Niño as a major factor that not only may aggravate COVID-19 incidence in the future,but also the broader health problem of ecosyndemic vulnerability in Latin America.

关键词： Coronavirus COVID-19 Ecosyndemic El Niño El Niño-Southern oscillation Infectious disease vulnerability Latin America

A Markov chain model of mixing kinetics for ternary mixture of dissimilar particulate solids

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Particuology 2017年第2期15卷 80-86页

作者： Vadim Mizonov ivan Balagurov Henri Berthiaux Cendrine Gatumel Department of Applied Mathematics Ivanovo State Power Engineering University Russia Centre RAPSODEE UMR CNRS 5302 Ecole des Mines d'Albi-Carmaux Campus Jarlard Route de Teillet 81000 Alhi France

This paper presents a simple but informative mathematical model to describe the mixing of three dissimilar components of particulate solids that have the tendency to segregate within one another. A nonlinear Markov chain model is proposed to describe the process. At each time step, the exchange of particulate solids between the cells of the chain is divided into two virtual stages. The first is pure stochastic mixing accompanied by downward segregation. Upon the completion of this stage, some of the cells appear to be overfilled with the mixture, while others appear to have a void space. The second stage is related to upward segregation. Components from the overfilled cells fill the upper cells （those with the void space） according to the proposed algorithm. The degree of non-homogeneity in the mixture （the standard deviation） is calculated at each time step, which allows the mixing kinetics to be described. The optimum mixing time is found to provide the maximum homogeneity in the ternary mixture. However, this “common” time differs from the optimum mixing times for individual components. The model is verified using a lab-scale vibration vessel, and a reasonable correlation between the calculated and experimental data is obtained

关键词： Ternary mixture Segregation Mixing kinetics Markov chain Matrix of transition probabilities Optimum mixing time

Solar flares with similar soft but different hard X-ray emissions： case and statistical studies

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Research in Astronomy and Astrophysics 2016年第1期16卷 39-50页

作者： ivan N.Sharykin Alexei B.Struminsky ivan V.Zimovets Wei-Qun Gan Space Research Institute Russian Academy of Sciences Moscow 117997 Russia Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

From the Reuven Ramaty High Energy Solar Spectroscopic Imager （RHESS1） catalog we select events which have approximately the same GOES class （high C - low M or 500-1200 counts s-1 within the RHESSI 6-12 keV energy band）, but with different maximal energies of detected hard X-rays. The selected events are subdivided into two groups：（1） flares with X-ray emissions observed by RHESSI up to only 50 keV and （2） flares with hard X-ray emission observed also above 50 keV. The main task is to understand observational peculiarities of these two flare groups. We use RHESSIX-ray data to obtain spectral and spa- tial information in order to find differences between selected groups. Spectra and images are analyzed in detail for six events （case study）. For a larger number of samples （85 and 28 flares in the low-energy and high-energy groups respectively） we only make some generalizations. In spectral analysis we use the thick- target model for hard X-ray emission and one temperature assumption for thermal soft X-ray emission. RHESSI X-ray images are used for determination of flare region sizes. Although thermal and spatial prop- erties of these two groups of flares are not easily distinguishable, power law indices of hard X-rays show significant differences. Events from the high-energy group generally have a harder spectrum. Therefore, the efficiency of chromospheric evaporation is not sensitive to the hardness of nonthermal electron spectra but rather depends on the total energy flux of nonthermal electrons.

关键词： Sun: flares -- Sun: X-rays -- gamma rays

Weighted Sum of Gray Gases Model Optimization for Numerical Investigations of Processes inside Pulverized Coal-Fired Furnaces

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Journal of Thermal Science 2017年第6期26卷 552-559页

作者： Nenad Crnomarkovic Srdjan Belosevic ivan Tomanovic Aleksandar Milicevic University of Belgrade Vinea Institute of Nuclear Sciences P. O. Box 522 11001 Belgrade Serbia

The effects of the number of significant figures （NSF） in the interpolation polynomial coefficients （IPCs） of the weighted sum of gray gases model （WSGM） on results of numerical investigations and WSGM optimization were investigated. The investigation was conducted using numerical simulations of the processes inside a pulverized coal-fired furnace. The radiative properties of the gas phase were determined using the simple gray gas model （SG）, two-term WSGM （W2）, and three-term WSGM （W3）. Ten sets of the IPCs with the same NSF were formcd for every weighting coefficient in both W2 and W3. The average and maximal relative difference values of the flame temperatures, wall temperatures, and wall heat fluxes were determined. The investigation showed that the results of numerical investigations were affected by the NSF unless it exceeded certain value. The increase in the NSF did not necessarily lead to WSGM optimization. The combination of the NSF （CNSF） was the necessary requirement for WSGM optimization.

关键词： Furnace Numerical simulation Significant figure Weighted sum of gray gases model Optimization

Entanglement Swapping in the Presence of White and Color Noise

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Communications in Theoretical Physics 2018年第2期69卷 143-153页

作者： ivan S. Dotsenko R. Korobka Taras Shevchenko National University of Kyiv Kyiv Ukrain

The influence of white and color noise on the outcome of the entanglement swapping process is investigated in a four-qubit system. Critical degree of noise in initial state, that could destroy entanglement in a result state is presented. The entanglement characteristics, such as concurrence, tangle, etc. are compared. Results could be helpful for experiments regarding entanglement swapping as conditions for initial quantum entangled states, to obtain entangled result state.

关键词： entanglement entanglement swapping white noise entanglement

Subwavelength grating devices in silicon photonics

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Science Bulletin 2016年第11期61卷 879-888页

作者： Junjia Wang ivan Glesk Lawrence R.Chen Department of Electrical and Computer Engineering Mc Gill University Department of Electronic and Electrical Engineering University of Strathclyde

Subwavelength grating(SWG) waveguides in silicon-on-insulator are emerging as an enabling technology for implementing compact, high-performance photonic integrated devices and circuits for signal processing and sensing applications. We provide an overview of our recent work on developing wavelength selective SWG waveguide filters based on Bragg gratings and ring resonators, as well as optical delay lines. These components increase the SWG waveguide component toolbox and can be used to realize more complex photonic integrated circuits with enhanced or new functionality.

关键词： Subwavelength gratings Siliconphotonics Integrated optics - Bragg gratings Ringresonators Optical delay lines

A future triple entry accounting framework using blockchain technology

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Blockchain(Research and Applications) 2021年第4期2卷 56-63页

作者： Moinak Maiti ivan Kotliarov Vitalii Lipatnikov Department of Finance National Research University-Higher School of EconomicsSaint Petersburg194100Russia Centre for Applied Research and Development National Research University Higher School of EconomicsSaint Petersburg194100Russia Saint Petersburg State University of Economics St Petersburg191023Russia

The study adopts a single case study approach to bring into conversation,ideas,and views of several scholars on triple entry accounting(TEA).The development of blockchain technology already drives the conscious move towards the *** TEA is currently not being used in any significant way but is in a greater debate whether it is worth adopting such alternative accounting practices as the *** to the TEA system is challenging and at present,it is just a fascinating mental *** these backdrops,the present study discusses the likelihood cases of future accounting practice namely:(Ⅰ)Sophisticated Accounting Software based on the double entry accounting(DEA);(Ⅱ)Combination of Blockchain and TEA;and(Ⅲ)Combination of disruptive technologies in addition to Blockchain and ***,the study concludes with describing the basic architecture of a potential system of triple-entry accounting that could support the TEA system to deliver real-time insights into business ***,the study plotted a hype cycle for accounting technologies to help global organizations identify the relevant accounting technologies and applications.

关键词： Double entry accounting Triple entry accounting Application programming interface Edge computing Blockchain

Quantum spin Hall effect in inverted InAs/GaSb quantum wells

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Frontiers of physics 2012年第2期7卷 200-207页

作者： ivan Knez (1) Rui-Rui Du (1) 1. Department of Physics and Astronomy Rice University Houston TX 77251-1892 USA

We review the recent experimental progress towards observing quantum spin Hall effect in inverted InAs/GaSb quantum wells （QWs）. Low temperature transport measurements in the hybridization gap show bulk conductivity of a non-trivial origin, while the length and width dependence of con- ductance in this regime show strong evidence for the existence of helical edge modes proposed by Liu et al. [Phys. Rev. Lett., 2008, 100： 236601]. Surprisingly, edge modes persist in spite of compa- rable bulk conduction and show only weak dependence on magnetic field. We elucidate that seeming independence of edge on bulk transport comes due to the disparity in Fermi-wave vectors between the bulk and the edge, leading to a total internal reflection of the edge modes.

关键词： quantum spin Hall effect InAs/GaSb quantum wells topological insulators