Double-scale Pulses Generated by Mode-locked Fibre Lasers and Their Applications

This chapter presents a detailed analysis of properties of double-scale pulses (also called noise-like pulses and femtosecond clusters) generated in fibre lasers and gives an in-depth discussion of promising applications of such pulses

Different generation regimes of mode-locked all-positive-dispersion all-fiber Yb laser

Different generation modes of all-positive-dispersion all-fibre Yb laser mode-locked due to effect of non-linear polarization evolution are investigated. For the first time we realized in the same laser both generation of single picoseconds pulse train and a newly observed lasing regime where generated are picosecond wave-packets, each being a train of femtosecond sub-pulses. Using both experimental results and numerical modeling we discuss in detail the mechanisms of laser mode-locking and switching of generation regimes and show a strong dependence of output laser characteristics on configuration of polarization controllers. A good qualitative agreement between experimental results and numerical modeling is demonstrated

Fraunhofer diffraction simulator for single slit

Разработана компьютерная модель для лекционной демонстрации дифракции Фраунгофера на щели в непрозрачном экране. Модель предусматривает возможность изменения длины волны и ширины щели с отображением на аудиторном экране результатов дифракции для нескольких наборов исходных параметров.Fraunhofer diffraction simulator for single slit is elaborated for physics lecture. The simulation provides the choice of the wave iength and the siii width. Resulting patterns are demonstrated onto auditorium screen for several chosen parameters

Improving the methodology for assessing the sustainable development of municipalities

The purpose of the article is to assess the level of sustainable development of municipalities and improve the assessment methodology by taking into account the budget sustainability index. The paper defines the concept of sustainable development of a municipality as a process of managing the ecologio-socio-economic system of a municipality that ensure the integral stability of the structure, elements and their connections. The current state of the urban districts of the Republic of Bashkortostan in dynamics in the period from 2015 to 2019 is analysed, the level of sustainability of municipal districts is assessed according to indicators of economic, environmental and social subsystems. The assessment methodology is supplemented by the following indicators of the budget subsystem: overall budget stability; budget deficit/surplus; total solvency; the ratio of accounts payable and local budget expenditures; the ratio of municipal debt and revenue; the level of budget balance

A New Method for Classifying Flares of UV Ceti Type Stars: Differences Between Slow and Fast Flares

In this study, a new method is presented to classify flares derived from the photoelectric photometry of UV Ceti type stars. This method is based on statistical analyses using an independent samples t-test. The data used in analyses were obtained from four flare stars observed between 2004 and 2007. The total number of flares obtained in the observations of AD Leo, EV Lac, EQ Peg, and V1054 Oph is 321 in the standard Johnson U band. As a result flares can be separated into two types, slow and fast, depending on the ratio of flare decay time to flare rise time. The ratio is below 3.5 for all slow flares, while it is above 3.5 for all fast flares. Also, according to the independent samples t-test, there is a difference of about 157 s between equivalent durations of slow and fast flares. In addition, there are significant differences between amplitudes and rise times of slow and fast flares.Comment: 46 pages, 7 figures, 4 tabels, 2010AJ....140..483

The statistical analyses of flares detected in B band photometry of UV Ceti type stars

In this study, we present the unpublished flare data collected from 222 flares detected in the B band observations of five stars and the results derived by statistical analysis and modeling of these data. Six basic properties have been found with a statistical analysis method applied to all models and analyses for the flares detected in the B band observation of UV Ceti type stars. We have also compared the U and B bands with the analysis results. This comparison allowed us to evaluate the methods used in the analyses. The analyses provided the following results. (1) The flares were separated into two types, fast and slow flares. (2) The mean values of the equivalent durations of the slow and the fast flares differ by a factor of 16.2 \pm 3.7. (3) Regardless of the total flare duration, the maximum flare energy can reach a different Plateau level for each star. (4) The Plateau values of EV Lac and EQ Peg are higher than the others. (5) The minimum values of the total flare duration increase toward the later spectral types. This value is called the Half-Life value in models. (6) Both the maximum flare rise times and the total flare duration obtained from the observed flares decrease toward the later spectral types.Comment: 17 pages, 10 figures, 8 table

Mode-locked fiber lasers with significant variability of generation regimes

We demonstrate a great variability of single-pulse (with only one pulse/wave-packet traveling along the cavity) generation regimes in fiber lasers passively mode-locked by non-linear polarization evolution (NPE) effect. Combining extensive numerical modeling and experimental studies, we identify multiple very distinct lasing regimes with a rich variety of dynamic behavior and a remarkably broad spread of key parameters (by an order of magnitude and more) of the generated pulses. Such a broad range of variability of possible lasing regimes necessitates developing techniques for control/adjustment of such key pulse parameters as duration, radiation spectrum, and the shape of the auto-correlation function. From a practical view point, availability of pulses/wave-packets with such different characteristics from the same laser makes it imperative to develop variability-aware designs with control techniques and methods to select appropriate application-oriented regimes

Проблемы формирования новой воспроизводственной роли промышленности

International audienceThe article describes the questions of formation of a new reproductive role of industry in development of national economy. Such problems as the level of depreciation of fixed assets, investments in fixed capital, lack of motivation for the introduction of new technologies and expanding the range of production have been highlighted.Рассматриваются вопросы формирования новой воспроизводственной роли промышленности в развитии национальной экономики. Отмечаются проблемы уровня износа основных фондов, инвестиций в основной капитал, отсутствия мотивов к внедрению новых технологий, расширения номенклатуры производства

Специфика воспроизводственной роли промышленности в современной экономике

International audienceSpecificity of modern industrial development is viewed from employment resources point. The authors state that the industrial sector in the post-industrial conditions acquires the features that integrate the basics of reproduction, forming the necessary conditions for the expanding of employment resources in other sectors of the economy.Рассматривается специфика современного промышленного развития с позиций занятости ресурсов. Аргументируется, что промышленный сектор в постиндустриальных условиях приобретает черты интегрирующей основы воспроизводства, формирующей необходимые условия для расширения занятости ресурсов в других секторах экономики