Self-injection locking of DFB laser diode with Brillouin amplification in optical fibre feedback

A novel optical injection-locking configuration utilising Brillouin amplification in optical fibre feedback is reported. The proposed structure exhibits properties inherent in two phenomena, self-injection locking and injection-locking in master-slave configuration at the same time. Significant narrowing of the locked DFB laser linewidth was recorded. The configuration provides intensity-stable Stokes generation without a high-frequency external modulator and generator.     

Examination of Pellets Made from Concentrate of Oxidized Ferruginous Quartzites of Mikhailovsky GOK

Metallurgist - The production of pellets from a concentrate of oxidized ferruginous quartzites that are tailings at the Mikhailovsky GOK pelletizing plant is studied. The conditions for the...     

Software for decision-making support in blast-furnace operation

Experience shows that the successful introduction of automated information systems at metallurgical enterprises largely depends on the technology and software selected. In the present work, the basic technology and software options available are briefly outlined. The starting point is Agile development, which is based on iterative procedures, the dynamic formation of user requirements, and their implementation through constant dialog within working groups consisting of various specialists (users, analysts, programmers, and testers). Iteration corresponds to relatively brief development times (as a rule, months), after which the user is given the next tested version of the software, with new functional properties. The list of additional functional properties in each new version represents user priorities and is drawn from the overall list of requirements before each iteration begins. In each iteration, the following procedures are completed in sequence: verification of the computational algorithm (with the introduction of new variables, where necessary); functional modeling of the system; improvement of subsystem structure; conceptual modeling of the database; generation of a model of the database; loading of the test data in the database; creation of the functional diagrams in the mathematical library; implementation of the subsystem’s client software; testing and debugging of the software; and the development of reference documentation. The Atlassian JIRA system is used to control individual tasks and monitor their overall realization within the process of collective software development. The Atlassian Bitbucket platform provides remote storage for code storage and control of the software version. On the basis of up-to-date approaches to software development, systems that are functional, reliable, east to use, expandable, and integrable may be created. Such systems are characterized by minimum risk and acceptable cost.     

Synthesis and properties of solid electrolyte Ce<Subscript>0.9</Subscript>Gd<Subscript>0.1</Subscript>O<Subscript>2–δ</Subscript> with Co,Cu, Mn,Zn doping

The influence of small additions (1, 3, 5 mol %) of transition metal (Co, Cu, Mn, Zn) oxides on the properties of solid electrolyte Ce_0.9Gd_0.1O_2–δ (GDC) have been investigated. It has been shown that the addition of dopants results in intensification of GDC sintering and reduction of the shrinkage end temperature by 300–400°C, which decreases in the sequence Zn–Mn–Co–Cu. The ultimate dopant concentration above which the further activation of GDC sintering does not occur is about 3 mol % for Co, Cu, and Mn and about 1 mol % for Zn. It has been shown that Co and Cu increase the total conductivity of GDC, while Mn and Zn decrease it.     

Web technology in automated information and modeling systems for metallurgical processes

The software in information systems used by engineering personnel at metallurgical enterprises is considered. Such software operates automated workstations, support systems for decision making, information and modeling systems, expert systems, and so on. Typically, the software takes the form of desktop applications written in high-level programming languages (Visual C#, Visual Basic, etc.). The analysis of technological information from the enterprise’s database-management server entails the solution of programming problems, systems of differential equations, and mathematical-physics problems, for example. Such problems are unsolvable by the standard general-purpose programming languages. Therefore, the development of information and modeling systems requires access to outside software, such as Microsoft Excel and MATLAB. Interaction with Microsoft Excel depends on COM Interop technology, which requires the installation of Microsoft Office on each client computer. Interaction with MATLAB requires the preliminary assembly of a library in MATLAB Compiler and its connection to the program. MATLAB Runtime freeware must be installed on the client computer. However, desktop applications using Windows Forms do not meet the requirements of industrial information systems in terms of functionality, accessibility, and cross-platform compatibility. Accordingly, new technologies must be found for the creation of information systems. The best approach is the construction of web applications based on the ASP.NET MVC framework, which permits the transfer of mathematical libraries and modules for interaction with Microsoft Excel and MATLAB from Windows Forms, without modification. The structure of the web application employed in the development of information-system software is described. The web page employed has the following functional regions: the logo and title of the current page, the session-status menu, the function menu, group operations, notifications, and the working area.     

A magneto-optical setup for studying the time evolution of nanoscale domain-wall displacements under pulsed magnetization

A magneto-optical setup for studying the time evolution of nanoscale domain-wall displacements of domain walls in magnetic films with a regular domain structure is described. Methods for spatial filtering of the output optical flux using the Fourier image of the domain structure and the impulse transient response in the real-time mode are applied in the setup. This allowed an increase in the sensitivity to domain-wall displacements of up to 5 nm and registration of their evolution with a temporal resolution of 1 ns.