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We present OSM Ski Resort Routing, an app that combines the concept of pathfinding and navigation with skiing. It provides an interactive 2D and 3D visualisation of arbitrary ski resorts using OpenStreetMap data and can be used to compute and display the optimal route between any waypoints in the resort.

We determined factors that arise during an arc discharge and detected possibility of their use to accelerate protection against arc closure. This enables creation of a combined device for accurate determination of an arc discharge. In particular, we can expand the spectrum of sensitivity of an optical sensor by the use of ultraviolet radiation without its replacement. We considered possibility of acceleration of response of protection against arc closure operation due to refusal of its blocking with relay circuits for maximum current protection and reduction of an influence of solar radiation on operation of PAC (protection against arc closure). We substantiated possibility of development of a more advanced device for protection against arc circuits, which gives possibility to expand the spectrum of the optical sensor in the region of ultraviolet radiation. We proposed the solution of the problem of increasing of sensitivity of protection against arc closure. This is possible by converting the ultraviolet radiation into a visible part of the optical spectrum, which will expand the spectrum of sensitivity of the optical sensor to the region of ultraviolet radiation and, accordingly, increase its sensitivity. This is due to the fact that 70 % of an arc discharge radiation falls on the ultraviolet region and only 15 % on the visible and infrared spectra of the optical radiation. The obtained results give grounds to assert about possibility of realization of a device of combined protection for determination of arc circuits in industrial production, as well as expansion of spectral sensitivity of optical sensors. In addition, we developed a combined device for determination of an arc discharge through a use of an ultrasound system. Known developments devoted to determination of location of an arc discharge by comparing intensity of a signal from a flash at both ends of the ten-meter optical light conductor are characterized by the fact that the maximum difference between the arrival time of signals from a flash point to sensors at the ends of the optical fibers is 5ns. This is a very low temporal level compared to the light conductor length at the velocity of 300,000 km/s. The system proposed in this study uses the sound velocity, which reaches 342/s, to determine an arc discharge, which simplifies a time measurement device for determination of a short circuit greatly and increases accuracy of time measurement by three orders of magnitude (10 3 ).

Modern fire-rescue turntable ladders are constructed in a lightweight mode to increase their maximum operation velocities, maximum length, and outreach respectively. Hence, the ladder has a limited stiffness and will be more and more subject to oscillations of deflection along with dominant overtones. This paper deals with the active oscillation damping of such ladders. A new feedforward and feedback control strategy is applied. The feedforward control is calculated through system inversion of a multi-body system utilizing its differentially flatness. The design of the feedback is based on partial differential equations (PDE) describing a Euler– Bernoulli model of a beam with a concentrated point mass at the end. The modal representation of the system is constructed based on the analytical form of the eigenfunctions. For active oscillation damping by feedback without a dynamical observer the ladder was equipped with a gyroscope additionally to strain gauges. Due to computational efforts and measurement noise a reduced state vector is disposed for stabilization. The proposed control approach allows damping the fundamental oscillation as well as the first dominant overtone and asymptotically stabilizing the system around the reference trajectory. Measurement results from the IVECO DLK 55 CS fire-rescue turntable ladder validate the good performance of the control.

In this contribution, a fuel cell-based power plant which uses water and methane to produce electrical power is considered. While earlier publications deal with the fuel cell only, this contribution takes the whole plant into account. The distributed modelling of the hydrogen producing reformer unit is presented. Methods are developed which allow for a fast and efficient simulation of the model equations. As the other parts of the power plant are of similar dynamical structure, the simulation methods are easily transferable. The identification of parameters for the power plant is performed on the basis of measurements and dynamic simulation. Sophisticated control concepts for the optimal operation of the power plant are proposed. They consider the whole plant and couplings between the various elements to maximise the plant's efficiency.

We describe a 128 GHz electron-spin-resonance spectrometer based on heterodyne detection with double frequency conversion utilizing cryogenic Schottky-diode mixers. Together with other mm-wave components installed into a dilution refrigerator cryostat, the mixers comprise a bridge operating at 1.5 K. A miniature Fabry–Perot resonator is used to detect samples of bulk and surface-adsorbed atomic hydrogen gas at temperatures below 100 mK. The sensitivity is 2×109 spins/Gauss at the excitation power of 20 pW.

This paper describes the further development of a real-time directional drilling digital interface (DDDI) that dynamically illustrates many aspects of the directional drilling process, specifically those that apply to positive displacement downhole drilling motors (PDM), rotary steerable systems (RSS), and motor driven rotary steerable systems (MD-RSS) while operating downhole. The ongoing development of advanced drilling engineering packages and intelligent downhole drilling tools provides increasing amounts of available drilling-related data. The DDDI uses data supplied by means of an existing real-time, rigsitebased drilling information acquisition and database system to help to address many of the challenges encountered during directional drilling. The interface processes data based on engineering models, empirical knowledge, and technical data; it presents dynamic operating parameter information and graphical representations of functioning downhole drilling equipment. Subject matter experts located in diverse global areas can remotely access the interface to observe and to contribute to multiple drilling applications. This paper provides details about the further development of the existing interface and its application to better optimize the real-time directional drilling process and to promote a balanced downhole system approach. The results have included reduced drilling equipment wear and damage, greater reliability, and reduced drilling costs. In addition to downhole motor and rotary steerable system applications, the DDDI was used during downhole motor-driven rotary steerable system (MD-RSS) operations; benefits were realized through the simultaneous monitoring of both rotary steerable tools and PDMs. After achieving real-time benefits in diverse global locations through the additional technical capabilities of the enhanced version of the DDDI, the potential benefits of a Russian language version were identified. The Russian language version enhanced the collaboration between English- and Russian-speaking personnel. The most recent DDDI version aids in the comprehensive conceptualization, reporting, and control of directional drilling operations. It has a positive effect on the overall drilling process and expands the technical knowledge base, which provides additional support of the directional drilling expert system objective.

This paper deals with the modelling and optimisation of a so-called glass feeder. A feeder is a kind of a channel connecting in this case the smelting furnace and the forming device of container glass facilities. For conditioning it is possible to influence the glass velocity by changing the discharging at the end and the temperature by gas burners along the feeder. This process can be described as a distributed parameter system and modelled by a partial differential equation, the corresponding initial and boundary conditions. Special experiments at a real production lead to a simplified solution in the time domain and thus to an easy parameter estimation. Finally the objective is an energy-optimal operation for a certain product (steady state) and a time-optimal transient behaviour between two products.

In the paper the two degree of freedom control for a glass feeder is considered. The mathematical model of the plant is described by a time-varying partial differential equation in one space dimension with a source function corresponding to the control input. The control output is the temperature at the end of the feeder. The boundary input being an entrance temperature of the glass smelt is treated as a disturbance. The proposed strategy decouples approximately the control output from the boundary input as well as from the influence of the time-varying mass flow. The design of the control strategy is based on the system description with power series and flatness property. This description allows to develop the feedforward control and the decoupling part of the feedback. The stability of the closed loop system is analysed with the Lyapunov method. Some experimental results are shown and demonstrate the efficiency of the proposed control strategy.

In glass industry, the energy for the manufacturing process plays an important role for the productivity of the plant. Till now, the process is mainly controlled based on experience of the operators. In the paper a method is presented for deriving optimized feedforward control strategies resulting in reference temperature profiles for the plant control. Therefore a dynamic model based on partial differential equation as an approximation for the glass feeder gate is derived. Measurements show a good agreement to the simulation model behavior. Next step is the development of a feedforward control based on an approach via a flat system description in combination with optimization techniques. The obtained result was an advantageous temperature profile, which leads to a reduction of gas consumption at the plant of approximately 6 to 8 %.

This work deals with a heat transfer process and an optimal control of an inhomogeneous partial differential equation describing this process. One considers a glass feeder gate, which is present at many glass manufacturers. The use of the offered study is a development of an optimal feedforward control for dynamic behavior of this heating process. A mathematical model of the glass feeder gate is presented by a nonlinear distributed parameter system. The control design is based on approaches of a flatness description of dynamic systems and a parameterization of a reference trajectory for the optimization of the dynamical behaviour. The control strategy must be sufficient for a number of requirements to process (e.g. output temperature at the end of the feeder gate) and must provide optimum quality criteria (consumption of power). Some simulation results are included and demonstrate the efficiency of the control.