411 research outputs found

    Does the complexity in temporal precipitation disaggregation matter for a lumped hydrological model?

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    Flood peaks and volumes are essential design variables and can be simulated by precipitation–runoff (P–R) modelling. The high-resolution precipitation time series that are often required for this purpose can be generated by various temporal disaggregation methods. Here, we compare a simple method (M1, one parameter), focusing on the effective precipitation duration for flood simulations, with a multiplicative cascade model (M2, 32/36 parameters). While M2 aims at generating realistic characteristics of precipitation time series, M1 aims only at accurately reproducing flood variables by P–R modelling. Both disaggregation methods were tested on precipitation time series of nine Swiss mesoscale catchments. The generated high-resolution time series served as input for P–R modelling using a lumped HBV model. The results indicate that differences identified in precipitation characteristics of disaggregated time series vanish when introduced into the lumped hydrological model. Moreover, flood peaks were more sensitive than flood volumes to the choice of disaggregation method. © 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group

    A five-year hedonic price breakdown for desktop personal computer attributes in Brazil

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    The purpose of this article is to identify the attributes that discriminate the prices of personal desktop computers. We employ the hedonic price method in evaluating such characteristics. This approach allows market prices to be expressed as a function, a set of attributes present in the products and services offered. Prices and characteristics of up to 3,779 desktop personal computers offered in the IT pages of one of the main Brazilian newspapers were collected from January 2003 to December 2007. Several specifications for the hedonic (multivariate) linear regression were tested. In this particular study, the main attributes were found to be hard drive capacity, screen technology, main board brand, random memory size, microprocessor brand, video board memory, digital video and compact disk recording devices, screen size and microprocessor speed. These results highlight the novel contribution of this study: the manner and means in which hedonic price indexes may be estimated in Brazil

    Homomorphic Training of 30,000 Logistic Regression Models

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    In this work, we demonstrate the use the CKKS homomorphic encryption scheme to train a large number of logistic regression models simultaneously, as needed to run a genome-wide association study (GWAS) on encrypted data. Our implementation can train more than 30,000 models (each with four features) in about 20 minutes. To that end, we rely on a similar iterative Nesterov procedure to what was used by Kim, Song, Kim, Lee, and Cheon to train a single model [KSKLC18]. We adapt this method to train many models simultaneously using the SIMD capabilities of the CKKS scheme. We also performed a thorough validation of this iterative method and evaluated its suitability both as a generic method for computing logistic regression models, and specifically for GWAS

    Аксіологічні виміри душпастирства у творах Іоана Золотоустого

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    Стаття Світлани Білоус "Аксіологічні виміри душпастирства у творах Іоана Золотоустого" присвячена пошуку джерел духовної опіки над людиною, витоки яких автор бачить у християнському середньовіччі. Життя і творча спадщина Іоана Золотоустого – яскравий приклад пояснення сутності й визначення ціннісної природи душпастирювання крізь призму поняття священства.Статья Светланы Билоус "Аксиологические измерения душпастирства в произведениях Іоана Золотоустого" посвящена поиску источников духовной опеки над человеком, истоки которіх автор видит в христианском средневековье. Жизнь и творческое наследство Иоанна Золотоустого – яркий пример объяснения сущности и определение ценностной природы душпастирства сквозь призму понятия священства.The article by Svitlana Bilous "Axiological dimensions of priesthood in the Ioan Zolotoustyi’s works" is dedicated to finding sources of spiritual care over a human, the origin of which the author sees in the Christian Middle Ages. The life and literary heredity of Ioan Zolotoustyi is a brilliant pattern of explaining the essence and definition of valuable ​​nature of pastoral care through the prism of the concept of the priesthood

    Orthogonalities and functional equations

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    In this survey we show how various notions of orthogonality appear in the theory of functional equations. After introducing some orthogonality relations, we give examples of functional equations postulated for orthogonal vectors only. We show their solutions as well as some applications. Then we discuss the problem of stability of some of them considering various aspects of the problem. In the sequel, we mention the orthogonality equation and the problem of preserving orthogonality. Last, but not least, in addition to presenting results, we state some open problems concerning these topics. Taking into account the big amount of results concerning functional equations postulated for orthogonal vectors which have appeared in the literature during the last decades, we restrict ourselves to the most classical equations

    Set-valued orthogonal additivity

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    We study the set-valued Cauchy equation postulated for orthogonal vectors. We give its general solution as well as we look for selections of functions satisfying the equation

    Ion mobility action spectroscopy of flavin dianions reveals deprotomer-dependent photochemistry

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    The intrinsic optical properties and photochemistry of flavin adenine dinucleotide (FAD) dianions are investigated using a combination of tandem ion mobility spectrometry and action spectroscopy. Two principal isomers are observed, the more stable form being deprotonated on the isoalloxazine group and a phosphate (N-3,PO4 deprotomer), and the other on the two phosphates (PO4,PO4 deprotomer). Ion mobility data and electronic action spectra suggest that photo-induced proton transfer occurs from the isoalloxazine group to a phosphate group, converting the PO4,PO4 deprotomer to the N-3,PO4 deprotomer. Comparisons of the isomer selective action spectra of FAD dianions and flavin monoanions with solution spectra and gas-phase photodissociation action spectra suggests that solvation shifts the electronic absorption of the deprotonated isoalloxazine group to higher energy. This is interpreted as evidence for significant charge transfer in the lowest optical transition of deprotonated isoalloxazine. Overall, this work demonstrates that the site of deprotonation of flavin anions strongly affects their electronic absorptions and photochemistry
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