Coherent Control of the Exciton Dynamics in the FMO Protein

We have achieved first steps toward coherent control of excitonic energy migration in the FMO pigment-protein complex, by combining femtosecond pulse shaping with a feedback loop using an evolutionary algorithm. The experimental conditions achieved, with a rotating sample, a cryostat, and a pulse shaper, are sufficient for closed loop optimizations.</p

Особенности воспроизведения цветов Pantone в электрофотографии

Цифровая печать становится все более популярной в современной полиграфии. Возможность точного воспроизведения цветов Pantone отсутствует в цифровых машинах, поскольку все цвета печатают с помощью CMYK-тонера и встроенной системы RIP. В работе оценивается качество воспроизведения смесевых цветов с внутренним и внешним профилем с различными настройками.Digital printing becomes moreand more popular in the modern polygraphy. The ability to reproduce the Pantone colors is missing in digital presses because all colors are printed with CMYK toner and built-in RIP. In this article the quality of reproducing spot colors with inner and outer iss-profile and different setting is evaluated

Что такое «мегалуч»?

Пленоптическая фотография является одной из технологий компьютерной фотографии. Параметр, определяющий разрешение подобных камер, в русскоязычной литературе именуется «мегалуч». В работе обсуждается происхождение и смысл данного термина, дается его численная оценка и связь с устоявшимся термином «пиксел». На примере пленоптической камеры Lytro LF сделана попытка подсчитать фактическое число мегалучей, которое фиксирует камера.Plenoptic photography is one of the computational photography technologies. Parameter called «megaray» determines the resolution of such cameras. The origin and meaning of the term are discussed in present paper. Numerical evaluation and relation to an existed term «pixel» is given. In addition, on the example of Lytro LF camera it has attempted to estimate the actual number of rays captured by Light-field camera

Linearization of inkjet plotter using tonal trajectory

Демонстрируются возможности градационных траекторий применительно к задачам линеаризации струйных цифровых печатных систем с использованием математического аппарата дифференциальной геометрии пространственных кривых. В настоящей работе вводится понятие градационной траектории, предлагается два критерия для их получения и алгоритм, основанный на этих критериях, рассматривается практическое применение градационных траекторий как таковых.The possibilities of gradation trajectories are applied to the problems of inkjet digital printing systems linearization using the mathematical methods.In this article the concept of gradation trajectory is introduced. Two criteria for the preparation of gradation trajectories and algorithm based on those criteria are proposed.The practical application of gradation trajectories as a method of linearization is considere

Технологии создания металлизированных эффектов в цифровой печати

В статье рассмотрены основные технологии достижения металлизированных эффектов в цифровой печати. Проанализированы особенности применения технологий, их влияние на удорожание изделия.This article describes the main technology to achieve metallic effects. The features of the application of technologies and their impact on the price of the product

The forward problem of spectral reflection prediction: Mutual match between framework selection and the training set volume

Novel technology of the color reproduction is closely related to a variety of color prediction techniques. Along with the deterministic models, those based on the use of artificial neural networks have recently begun to appear. An important problem in the application of a neural network approach is the choice of the training set and network training algorithms. In our work, we describe the results of a computational experiment where various configurations of the artificial neural networks along the different volumes of training subsamples were simultaneously determined providing a satisfactory accuracy of the spectral reflection prediction. The results show that each subsample might be mapped to a particular network configuration. © 2020 American Institute of Physics Inc.. All rights reserved

The inverse problem of spectral reflection prediction: Problems of framework selection

Digital image processing requires substantial computations for characterization. It is since the reliable color reproduction can be achieved by establishing the correspondence between the spectral reflectance of the printed surface and the amounts of deposited inks. The processing is implemented by using different mathematical models. Most of the color prediction models engage some mathematical techniques to predict spectral reflectance for a mixture of colorants that are characterized by absorption and scattering during the light propagation. However, few attempts were made to make a model for prediction the colorants values based on an observing spectrum. This work is devoted to application of artificial neural network approach for solving the inverse problem of spectral reflection prediction. This task has been considered unsolvable as it involves solving a system of the linear differential equations, in which the number of unknowns exceeds the number of equations. Our attempt is based on the assumption that the prediction of the initial colorants from spectral data is possible by analogy with the work of the color perception system in humans. The aim of our study is to offer an approach to the framework selection. The model is built in Matlab and shows satisfactory prediction accuracy. © 2020 American Institute of Physics Inc.. All rights reserved

Determining the ideal initial printing colorants in electrophotography by the discrete gradation trajectories

The accuracy and repeatability of the color reproduction in print is determined by the fine-tuning of the tone reproduction curves of the basic printing colorants (most often this is CMYK). However, the diversity of manufacturers of printing equipment and dyes introduces an element of significant uncertainty about color uniformity. In addition, the traditional approach does not take into account the effect of hue change when applying the original dyes, as well as the nonlinearity of the hue rise in high- and low-density areas. Determining the color of base colorants that produces the most uniform tone change is an important engineering challenge. Previously, there was no scientific basis for such calculations. We recently proposed an alternative color correction model based on gradation trajectories as an analogue of gradation curves in the CIE Lab space. We have also described the extension of the approach to double color overlay (gradation surfaces) and its analytical and discrete implications. The trajectories are the geodetic lines on gradation surfaces. In this paper, we propose using the gradation trajectories to determine “ideal” or “true” initial printing dyes for electrophotography. To simplify calculations, natural color discretization in digital printing is used. © 2022 John Wiley & Sons, Ltd.Wake Forest University, WFUSupport for this research was provided by the Babcock Graduate School of Management, Wake Forest University; Rutgers Business School – Newark and New Brunswick, Rutgers University; and the Jones Graduate School of Management, Rice University. Helpful comments on earlier versions of this chapter were provided by Jack Brittain, Margaret Duval, Reuben McDaniel, Tim Ruefli, John Slocum, Kathie Sutcliffe, and Doug Wholey

Mathematics and practice of color space invariants by the example of determining the gray balance for a digital printing system

In modern printing, a large number of tasks are associated with the mutual transformation of color spaces. In particular, the most common pair of hardware-dependent color spaces is RGB and CMYK, the mutual transformation of colors in which is ambiguous, which creates significant problems in color reproduction. To solve this problem, we propose using color space invariants — gradation trajectories and gradation surfaces, which are analogs of gradation curves for initial col-orants and their binary overlays, constructed in the absolute color space of the CIE Lab. Invariants are introduced on the basis of the mathematical apparatus of the differential geometry of spatial curves and surfaces. Practical application of color space invariants involves certain difficulties associated with their complex analytical description; moreover, for most practical problems, the high accuracy of the model is redundant. For the practical application of invariants, we propose a simpler approach using natural color sampling in digital printing systems. As an example, the procedure for determining the gray balance for an electrophotographic printing press is given. © 2020, Institution of Russian Academy of Sciences. All rights reserved

An analysis of quadrupole splitting of the Mössbauer spectra of ferritin and iron-dextran complexes in relation to the iron core microstructural variations

Mössbauer spectra of human liver ferritin and some pharmaceutically important iron-dextran complexes as ferritin models were measured at 87 K (frozen solutions) and at both 87 and 295 K (lyophilized forms). The Mössbauer spectra consisted of paramagnetic doublets only. However, the spectral line shapes were not Lorentzian and these Mössbauer spectra were better fitted using a superposition of two or more quadrupole doublets or using a distribution of quadrupole splittings. The differences of the maximal quantity of quadrupole doublets for better fitting of various Mössbauer spectra of ferritin and iron-dextran complexes were compared with the fitting using the distribution of quadrupole splitting for additional analysis. It is possible that variations of the quantity of quadrupole doublets for better fitting of Mössbauer spectra of ferritin and iron-dextran complexes may be related to heterogeneous iron cores in the samples. This heterogeneity is supposed to be different for various samples and changed for lyophilized samples and for frozen solutions as well as for various temperatures