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A Generative Model For Electron Paths [article]

John Bradshaw, Matt J. Kusner, Brooks Paige, Marwin H. S. Segler, José Miguel Hernández-Lobato
2019 arXiv   pre-print
Instead of predicting product molecules directly from reactant molecules in one shot, learning a model of electron movement has the benefits of (a) being easy for chemists to interpret, (b) incorporating  ...  We propose an electron path prediction model (ELECTRO) to learn these sequences directly from raw reaction data.  ...  ACKNOWLEDGEMENTS We would like to thank Jennifer Wei, Dennis Sheberla, and David Duvenaud for their very helpful discussions.  ... 
arXiv:1805.10970v2 fatcat:7hou5agtsbg6zhdgddqsqvetjy

Simulating trends in reaction path geometry as a function of external fields. A generalized electronic diabatic model for two-dimensional energy surfaces

Gustavo A. Arteca, Jean Pierre Rank, Orlando Tapia
2008 International Journal of Quantum Chemistry  
We introduce a protocol to represent quantum states as a linear superposition of model electronic diabatic basis states coupled in an external (static) electric field.  ...  By considering an entire family of these models, we uncover trends in reaction-path geometry and the topology of potential-energy surfaces, including all those that can be realized in a two-dimensional  ...  The general quantum states for the nonisolated three-state model system become: ⌽͑q; , ϭ c 1 ͑͒ 1 ͑q͒ ϩ c 2 ͑͒ 2 ͑q͒ ϩ c 3 ͑͒ 3 ͑q͒.  ... 
doi:10.1002/qua.21645 fatcat:a3duql2banhknbs5igjrpzwxom

A generative model for electron paths [article]

J Bradshaw, MJ Kusner, B Paige, MHS Segler, JM Hernández-Lobato, Apollo-University Of Cambridge Repository
2020
Instead of predicting product molecules directly from reactant molecules in one shot, learning a model of electron movement has the benefits of (a) being easy for chemists to interpret, (b) incorporating  ...  We propose an electron path prediction model (ELECTRO) to learn these sequences directly from raw reaction data.  ...  ACKNOWLEDGEMENTS We would like to thank Jennifer Wei, Dennis Sheberla, and David Duvenaud for their very helpful discussions.  ... 
doi:10.17863/cam.55900 fatcat:k5bachv6n5fqxcyjdd2ciw5vvu

Electronic Word of Mouth Model Based on Social Complex Network

2016 Revista Técnica de la Facultad de Ingeniería Universidad del Zulia  
strategies of word of mouth propagation jam and the reasonable solutions for the electronic word of mouth propagation.  ...  This paper applies the improved model of social network electronic word of mouth from the perspective of complex networks, and studies the impact of network topology on the electronic word of mouth, then  ...  Generation of the Propagation Path The generation of the pate has two steps: Firstly, a set of effective paths are generated under the normal electronic word of mouth propagation condition, then the additional  ... 
doi:10.21311/001.39.4.28 fatcat:4ordc7soxjhfzn3oukppl3b6ey

Generalized cascaded model to assess noise transfer in scintillator-based x-ray imaging detectors

Ho Kyung Kim
2006 Applied Physics Letters  
For a scintillator-based x-ray imaging detector, the conventional cascaded model is generalized to describe the direct x-ray induced quantum noise.  ...  In this study, to consider the direct x-ray induced noise, the cascaded model is generalized by incorporating an additional parallel cascading path for the signal and noise transfers due to the direct  ...  For a scintillator-based x-ray imaging detector, the conventional cascaded model is generalized to describe the direct x-ray induced quantum noise.  ... 
doi:10.1063/1.2398926 fatcat:3au4aimh2fd2zaxqraxjnwsygi

Energy Losses and Mean Free Paths of Electrons in Silicon Dioxide

J. C. Ashley, V. E. Anderson
1981 IEEE Transactions on Nuclear Science  
The model energy-loss function is employed to calculate electron inelastic mean free paths and stopping powers for electrons with energies £ 10 keV in Si Op.  ...  MASTER Theoretical models and calculations are combined with experimental optical data to determine a model energy-loss function for SiOo.  ...  a model energy-loss function for SiOg.  ... 
doi:10.1109/tns.1981.4335688 fatcat:3ufzhbdflvhhhlprkoup3hgjnu

Exchange Symmetries in Motzkin Path and Bargraph Models of Copolymer Adsorption

E. J. Janse van Rensburg, A. Rechnitzer
2002 Electronic Journal of Combinatorics  
This relation is particularly useful in solving for the generating functions of certain models of vertex-coloured Dyck paths; this is a directed model of copolymer adsorption, and in a particular case  ...  In a previous work [26], by considering paths that are partially weighted, the generating function of Dyck paths was shown to possess a type of symmetry, called an exchange relation, derived from the exchange  ...  Whittington for their helpful discussions. E. J. Janse van Rensburg is supported by an operating grant from NSERC (Canada).  ... 
doi:10.37236/1637 fatcat:4umiopjpi5gixcdr4zaq5zpjr4

Slant total electron content for Sirio-Mortelliccio ray path

P. Spalla, R. G. Ezquer, M. A. Cabrera
2006 Annals of Geophysics  
In this work the Slant Total Electron Content (STEC) was calculated with a technique that uses so-called «auxiliaries stations model», and a Chapman layer with scale height equal to atomic oxygen scale  ...  In general, the deviations between predictions and measurements were lower than 30% for 16 h per day (average).  ...  It can be seen that, in general, there is a good agreement between CHO model and measurements for solstices (June and December), 16 hours per day (average).  ... 
doi:10.4401/ag-3105 doaj:cab8bd4cad2946b19f178dd03b1b7d0b fatcat:nzddtmmmqzfjlmsradamqxsqay

The propagation and growth of whistler mode waves generated by electron beams in Earth's bow shock

Robert L. Tokar, Donald A. Gurnett
1985 Journal of Geophysical Research  
Using a simple model for the shock, ray paths for the generated whistler mode waves are calculated.  ...  Model Electron Distribution Function It is desirable to obtain a model electron distribution function that is a function of position within the shock transition region so that the generation, propagation  ... 
doi:10.1029/ja090ia01p00105 fatcat:tretma6kzjebhbeprj2n6yuc7y

The inelastic mean free paths of electrons in semiconducting III-V compounds

C. M. Kwei, L. W. Chen
1988 Surface and Interface Analysis  
These calculations are based on a model dielectric function for the response of the valence band and the local-plasma-approximation for the response of inner shells.  ...  The inelastic mean free path of electrons in solids is an important parameter in surface studies using AES and XPS.  ...  Although the electron-gas model is a good approximation for the so-called free-electron-like materials having a simple energy loss spectrum with a single, dominant plasmon peak, the model is not good for  ... 
doi:10.1002/sia.740110107 fatcat:3znsk2jl2vbzfhaljrty2xzqwi

Generation of a strong attosecond pulse train with an orthogonally polarized two-color laser field

Chul Min Kim, I Jong Kim, Chang Hee Nam
2005 Physical Review A. Atomic, Molecular, and Optical Physics  
The origin of these behaviors is elucidated by analyzing semiclassical electron paths and by simulating high-harmonic generation quantum mechanically.  ...  We theoretically investigate the high-order harmonic generation from a neon atom irradiated by an intense two-color femtosecond laser pulse, in which the fundamental field and its second harmonic are linearly  ...  Jung-Hoon Kim for his critical comments. This research was supported by the Korea Science and Engineering Foundation ͑KOSEF͒ through the Creative Research Initiative Program.  ... 
doi:10.1103/physreva.72.033817 fatcat:xcyxirzqmncz3o2r6stuggl4oi

Path integral of the Holstein model with aϕ4on-site potential

Marco Zoli
2005 Physical Review B  
We derive the path integral of the semiclassical, one dimensional anharmonic Holstein model assuming that the electron motion takes place in a bath of non linear oscillators with quartic on site hard (  ...  Soft on site potentials generate attractive centres at large amplitude oscillator paths and contribute to the anomalous shape of the heat capacity over temperature ratio in the intermediate to low T range  ...  This guarantees that V (u(τ )) is generally repulsive in Fig.1(c) and attractive for a broad class of paths in Fig.1(d) .  ... 
doi:10.1103/physrevb.72.214302 fatcat:lqad2pcstnb73pnnxvq6p5fk6q

Research and Implementation of Global Path Planning for Unmanned Surface Vehicle Based on Electronic Chart [chapter]

Yanlong Wang, Xu Liang, Baoan Li, Xuemin Yu
2017 Advances in Intelligent Systems and Computing  
The simulation results show that the environmental model construction method and the improved A* algorithm can generate safe and reasonable global path.  ...  In order to solve the problem of global path planning of USV, this paper proposes an improved A* algorithm for sailing cost optimization based on electronic charts.  ...  Electronic chart analysis base on C++ language, environment modeling and path planning simulates with python. For a sea area in the South China Sea (regional range of 18.  ... 
doi:10.1007/978-3-319-65978-7_80 fatcat:sqigrr3iy5f2fdmwi5lypuvwvi

Nonlocal Electron Heat Transport in Magnetized Dense Plasmas

Akio NISHIGUCHI
2014 Plasma and Fusion Research  
Under a very strong magnetic field, the effective electron mean free path becomes shorter than the scale length of the temperature gradient and the results of the FP and linear models agree well.  ...  Nonlocal electron heat transport in magnetized dense plasmas is studied numerically using a nonlinear Fokker-Planck (FP) model with self-consistent electric fields.  ...  The mean free path of all electrons becomes much shorter than the scale length of the temperature gradient; thus, a classical diffusion model can be used even for high-energy electrons.  ... 
doi:10.1585/pfr.9.1404096 fatcat:6xhfxbfz6nhvnc5ogv2qciqlvq

Modeling of Signal Generation Function and Electron Penetration Effects on the EBIC Signal of Schottky diodes of Ge

Beggah Yamina, Lahreche Abderezzek
2008 American Journal of Applied Sciences  
The present study shows that simple forms for the generation functions, if connected to appropriate electronic path (electron range), can be successfully used to describe the collection efficiency in EBIC  ...  Both uniform and point-like source generation functions are considered here and for which two phenomenological electronic paths, depending on the incident beam energy, are obtained.  ...  We can conclude that each form of generation must be coupled with an electronic path specific for it.  ... 
doi:10.3844/ajassp.2008.678.682 fatcat:xezmyaiawffoxishijnwtajary
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