Optical time-domain reflectometer (OTDR) is used to characterize fiber optic links by identifying and localizing various refractive and reflective events such as breaks, splices, and connectors, and measuring insertion/return loss and fiber length. Essentially, OTDR inserts a pulsed signal into the fiber, from which a small portion that is commonly referred to as Rayleigh backscatter, is continuously reflected back with appropriate delays of the reflections expressed as the power loss versus distance, by conveniently scaling the time axis. Specifically, for long-distance events visibility and measurement accuracy, the crucial OTDR attribute is dynamic range, which determines how far downstream the fiber can the strongest transmitted optical pulse reach. As many older-generation but still operable OTDR units have insufficient dynamic range to test the far-end of longer fibers, we propose a simple and cost-effective solution to reactivate such an OTDR by inserting a low-noise high-gain optical preamplifier in front of it to lower the noise figure and thereby the noise floor. Accordingly, we developed an appropriate dynamic range and distance span extension model which provided the exemplar prediction values of 30 dB and 75 km, respectively, for the fiber under test at 1550 nm. These values were found to closely match the dynamic range and distance span extensions obtained for the same values of the relevant parameters of interest by the preliminary practical OTDR measurements conducted with the front-end EDFA optical amplifier, relative to the measurements with the OTDR alone. This preliminary verifies that the proposed concept enables a significantly longer distance span than the OTDR alone. We believe that the preliminary results reported here could serve as a hint and a framework for a more comprehensive test strategy in terms of both test diversification and repeating rate, which can be implemented in a network operator environment or professional lab.

In this paper we consider the problem of finding a Nash equilibrium (NE) via zeroth-order feedback information in games with merely monotone pseudogradient mapping. Based on hybrid system theory, we propose a novel extremum seeking algorithm which converges to the set of Nash equilibria in a semi-global practical sense. Finally, we present two simulation examples. The first shows that the standard extremum seeking algorithm fails, while ours succeeds in reaching NE. In the second, we simulate an allocation problem with fixed demand.

Paint production and for that colour mixing is an important process which has wide applications in several field. There are various kinds of colour mixing that can be done. It can either be additive colour mixing or subtractive colour mixing. Generally, there are various kinds of paint mixing machines available in the market. They vary in their size, shape, technology and methodologies. The aim of this paper is to present a calculation and analyse of hydraulic system for paint mixing machine. The paint mixing machine has the task of mixing the oil paint components in vessel until the finished mass is obtained. As oil paint is a typical representative of rheological materials where the viscosity depends on the shear rate, it is necessary to mix different paint structures during processing at different speeds - the number of revolutions of the propeller must be changes.

Based on kadi sicils and Franciscan chronicles, this paper seeks to present a picture of everyday lives of Christians and Muslims during a turbulent period, marked by political turmoil, unrest and general insecurity. Attacks, murders and various other acts of violence were part of everyday life. The ruling class of the time often abused their position and acted beyond their authority, putting additional pressure on the Christian population and further aggravating their social position and security within Eyalet of Bosnia. The efforts of the authorities to protect reaya were only temporarily effective in stopping the violence. The

Forests in Europe are, at present not endangered by soil erosion, however, this can change with climate change or intensified forest management practices. Using a newly established network of plots in beech forests across Europe, the aims of this study were 1) discrimination of soil properties and erodibility indices in relation to bedrock, 2) determination of geochemical properties and Corg influencing erodibility, and 3) assessment of the effect of soil depth on erodibility indices. Seventy-six soil samples from 20 beech forests were collected in 11 countries to quantify soil properties influencing erodibility indices clay ratio, modified clay ratio, sodium adsorption ratio, and oxides ratio. Results indicate that dominant soil properties, determined by bedrock, that correlate with forest soil erodibility indices are: Corg, pH, EC, Ca and Na ion concentrations, total-water soluble cations, and the % of sand. According to the tested indices, soil susceptibility to erosion follows the sequence: granite>andesite>sandstone>quartzite>limestone. Deeper soil horizons on granite are more susceptible to erosion than surface horizons, while this is not the case for soils on limestones. In conclusion, forest management should consider the predisposition of different soil types to erosion.

Networked industrial systems capitalize on recent advancements in sensing, communications, computing and storage to improve productivity, operational and cost efficiency. The proliferation of effective techniques for knowledge extraction drive a paradigm shift in industrial environments and provide a fertile ground for enhanced process monitoring and control capabilities. In an effort to shed light on industrial data management operations, this paper presents two different approaches for dealing with information processing tasks of aggregated sensor measurements. Such tasks constitute part of an end-to-end process monitoring solution which is implemented in an open-source platform following a modular, scalable and interpretable procedure. A mapping of the industrial data processing components to the operational principles and architecture of a cyber-physical system reveals useful insights for an automated supervision of critical processes and workflows.

The paper focuses on the design and development of a two-wheeled and self-balancing robot as well as its control. The problem is equivalent to the inverted pendulum principle of balancing robots. Dynamic model based PD controller and empirical controller were designed. These controllers are used in closed loop system to provide the robot balance, even when robot is slightly pushed, which normally causes it to fall. The equations of robot motion were derived using Lagrangian and mapped to a transfer function in the complex s-domain. The controller parameters are initially tuned using PID Tuner in Simulink. Then, the zero-order-hold discretization method was applied to implement this control on the Arduino microcontroller. Furthermore, the controller parameters are additionally adjusted through experiments in order to exhibit better control performance. Moreover, the effect of an unexpected disturbance on the robot was taken into consideration. The effectiveness of the designed controllers was verified experimentally.

This paper is focused on investigating a new approach for collecting the data about robot’s position and orientation from the RoboDK software in which the robot’s movement is simulated. The code, as well as the GUI (Graphical User Interface) was developed using MATLAB environment and connection between the two software packages was achieved through the TCP (Transmission Control Protocol) internet protocol. Robot model used for this purpose is the Unimation’s PUMA 560 industrial robot which can be found in the online library of the RoboDK. Information regarding robot joint angles is important for planning the robot’s movement and generating the trajectory between the two positions, so it could be of use to have all the position/orientation vectors listed for further calculations. Drawback of the RoboDK software is the inability to generate the trajectory so the goal of this project is to avoid that problem with the help of the MATLAB software.

The goal of this article is to describe a power measuring system using the frequency-locked-loop (FLL). The FLLs have a wide variety of applications such as power converters, grid synchronization, sensorless flux estimation and control of motor drives. This nature of the FLL system allows for it to be a potentially perfect tool for power calculation. In this article, a new power calculation method has been presented. This method is based on FLL as part of phase locked loop (PLL) and has enhanced feature over classical methods for power calculation widely used in industry. The obtained results showcase the effectiveness of the proposed FLL power calculation method.

The OPENQKD project is demonstrating deployed QKD networks in several European cities. We present a virtual QKD testbed that allows the user to monitor live data but also to re-enact the past QKD exchange over the various links, together with a QKD network simulation tool.