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Related papers: An Improved Parameterization Procedure for NDDO-De…

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Semiempirical molecular orbital (SEMO) models based on the neglect of diatomic differential overlap (NDDO) approximation efficiently solve the self-consistent field equations by rather drastic approximations. The computational efficiency…

Chemical Physics · Physics 2018-12-11 Tamara Husch , Alain C. Vaucher , Markus Reiher

Computational studies of chemical reactions in complex environments such as proteins, nanostructures, or on surfaces require accurate and efficient atomistic models applicable to the nanometer scale. In general, an accurate parametrization…

Chemical Physics · Physics 2020-02-18 Christoph Brunken , Markus Reiher

These lecture notes introduce some simple effective Hamiltonians (also known as semi-empirical models) that have widespread applications to solid state and molecular systems. They are aimed as an introduction to a beginning graduate…

Chemical Physics · Physics 2016-09-08 B. J. Powell

In this work we develop a Hessian-based sampling method for the construction of goal-oriented reduced order models with high-dimensional parameter inputs. Model reduction is known very challenging for high-dimensional parametric problems…

Numerical Analysis · Mathematics 2018-09-28 Peng Chen , Omar Ghattas

For a large class of variational quantum circuits, we show how arbitrary-order derivatives can be analytically evaluated in terms of simple parameter-shift rules, i.e., by running the same circuit with different shifts of the parameters. As…

Quantum Physics · Physics 2021-03-03 Andrea Mari , Thomas R. Bromley , Nathan Killoran

Neural network (NN) model chemistries (MCs) promise to facilitate the accurate exploration of chemical space and simulation of large reactive systems. One important path to improving these models is to add layers of physical detail,…

Chemical Physics · Physics 2018-04-04 John E. Herr , Kun Yao , Ryker McIntyre , David Toth , John Parkhill

A common task is the determination of system parameters from spectroscopy, where one compares the experimental spectrum with calculated spectra, that depend on the desired parameters. Here we discuss an approach based on a machine learning…

Quantum Physics · Physics 2022-05-04 Farhad Taher-Ghahramani , Fulu Zheng , Alexander Eisfeld

A singularly perturbed linear system of second order ordinary differential equations of reaction-diffusion type with given boundary conditions is considered. The leading term of each equation is multiplied by a small positive parameter.…

Numerical Analysis · Mathematics 2009-06-23 M. Paramasivam , S. Valarmathi , J. J. H. Miller

We introduce a new method of estimation of parameters in semiparametric and nonparametric models. The method is based on estimating equations that are $U$-statistics in the observations. The $U$-statistics are based on higher order…

We present an efficient finite difference method for the approximation of second derivatives, with respect to system parameters, of expectations for a class of discrete stochastic chemical reaction networks. The method uses a coupling of…

Quantitative Methods · Quantitative Biology 2012-10-16 Elizabeth Skubak Wolf , David F. Anderson

In this article we consider Bayesian parameter inference associated to partially-observed stochastic processes that start from a set B0 and are stopped or killed at the first hitting time of a known set A. Such processes occur naturally…

Computation · Statistics 2012-01-19 Ajay Jasra , Nikolas Kantas

We present an exhaustive study of more than 250 ab initio potential energy surfaces (PESs) of the model dipeptide HCO-L-Ala-NH2. The model chemistries (MCs) used are constructed as homo- and heterolevels involving possibly different RHF and…

Quantitative Methods · Quantitative Biology 2013-06-21 Pablo Echenique , J. L. Alonso

We present a Bayesian methodology for infinite as well as finite dimensional parameter identification for partial differential equation models. The Bayesian framework provides a rigorous mathematical framework for incorporating prior…

Quantitative Methods · Quantitative Biology 2016-05-17 Eduard Campillo-Funollet , Chandrasekhar Venkataraman , Anotida Madzvamuse

A fully Bayesian approach is proposed for ultrahigh-dimensional nonparametric additive models in which the number of additive components may be larger than the sample size, though ideally the true model is believed to include only a small…

Methodology · Statistics 2013-09-24 Zuofeng Shang , Ping Li

We consider the Heston model as an example of a parameterized parabolic partial differential equation. A space-time variational formulation is derived that allows for parameters in the coefficients (for calibration) as well as choosing the…

Numerical Analysis · Mathematics 2014-08-13 Antonia Mayerhofer , Karsten Urban

In the following article we provide an exposition of exact computational methods to perform parameter inference from partially observed network models. In particular, we consider the duplication attachment (DA) model which has a likelihood…

Computation · Statistics 2013-06-20 Junshan Wang , Ajay Jasra , Maria De Iorio

Identification of the optimal quantum metrological protocols in realistic many particle quantum models is in general a challenge that cannot be efficiently addressed by the state-of-the-art numerical and analytical methods. Here we provide…

Approximate Newton methods are a standard optimization tool which aim to maintain the benefits of Newton's method, such as a fast rate of convergence, whilst alleviating its drawbacks, such as computationally expensive calculation or…

Artificial Intelligence · Computer Science 2015-08-07 Thomas Furmston , Guy Lever

As we all known, the nonnegative matrix factorization (NMF) is a dimension reduction method that has been widely used in image processing, text compressing and signal processing etc. In this paper, an algorithm for nonnegative matrix…

Numerical Analysis · Mathematics 2013-05-27 Shu-Zhen Lai , Hou-Biao Li , Zu-Tao Zhang

We made a comparative analysis of numerical methods for multidimensional optimization. The main parameter is a number of computations of the test function to reach necessary accuracy, as it is computationally "slow". For complex functions,…

Instrumentation and Methods for Astrophysics · Physics 2013-10-09 Ivan L. Andronov , Maria G. Tkachenko
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