Finding a Nash Equilibrium in Spatial Games is an NP-Complete Problem

We consider the class of (finite) spatial games. We show that the problem of determining whether there exists a Nash equilibrium in which each player has a payoff of at least k is NP-complete as a function of the number of players. When each player has two strategies and the base game is an anti-coordination game, the problem is decidable in polynomial time.spatial games; NP-completeness; graph K-colorability

Experimental implementation of a real-time token-based network protocol on a microcontroller

The real-time token-based RTnet network protocol has been implemented on a standard Ethernet network to investigate the possibility to use cheap components with strict resource limitations while preserving Quality of Service guarantees. It will be shown that the proposed implementation is feasible on a small network. For larger networks a different approach is necessary, using delegation by means of proxies. A delegation proposal will be discussed. For small networks it is possible to use a PIC microcontroller in combination with a standard Ethernet controller to run the RTnet network protocol. As more systems are added to the network the performance of this combination becomes insufficient. When this happens it is necessary for the microcontroller to delegate some tasks to a more powerful master and to organize a low-level communication protocol between master and slave

Загрязнение поверхностных вод в пределах г. Уфы

В статье рассматривается состояние поверхностных вод водных объектов в пределах г. Уфы. Сравнение концентраций загрязняющих веществ в створах различных частей города позволяет определить особенности влияния источников на загрязнение водной среды в пределах г. Уфы.The article considers the surface waters state of water bodies within the Ufa city. Comparison of pollutants concentrations of in cross-sections different parts of the city allows to deterстворmine the peculiarities of the sources influence on the aquatic environment pollution within the city of Ufa

Non-Waste-Wachsschalungen: Neuartige Präzisions-Schalungen aus 100 % recycelbaren Industrie-Wachsen zur Herstellung von geometrisch komplexen Beton-Bauteilen

Die neuen 3D-Entwurfs-, Berechnungs- und Fertigungsverfahren in Kombination mit dem Werkstoff ultrahochfester Beton (UHPC) bieten das Potenzial, den Beton-Leichtbau zu revolutionieren [1]. Die Herausforderung bei der Herstellung von geometrisch komplexen und hochpräzisen UHPC-Bauteilen liegt dabei im Schalungsbau. Da bisher keine verfügbaren abfallfreien und somit nachhaltigen alternativen Schalungsmaterialien bzw. -systeme identifiziert werden konnten, wurde der Forschungsansatz entwickelt, frei geformte Schalungen für Betonbauteile unter Verwendung von CNC-gefrästen recycelbaren Industriewachsen zu verwenden. Die Erforschung dieses Ansatzes hin zu einer anwendbaren Non-Waste-Schalungstechnologie wurde in einem gemeinsamen Forschungsprojekt des Instituts für Werkzeugmaschinen und Fertigungstechnik (IWF) und des Instituts für Tragwerksentwurf (ITE) der TU Braunschweig durchgeführt. Im Folgenden werden die wesentlichen Inhalte des Vorhabens, ausgehend von der Auswahl geeigneter Wachse, über die Untersuchung der Zerspanbarkeit bis hin zur Betonierung und anschließenden Analyse der Schalungen und Abgüsse, vorgestellt und diskutiert. Grundlegende Erkenntnisse wurden u. a. bereits 2016 in [2]–[5] veröffentlicht. Diese werden hier teilweise wiedergegeben und zudem mit zusätzlichen Informationen ergänzt. Die wesentlichen Erkenntnisse aus dem Forschungsvorhaben werden zusammengefasst. Ausführliche Informationen zur Entwicklung der Non-Waste-Wachsschalungstechnologie finden sich in der 2019 veröffentlichten Dissertation von Jeldrik Mainka [6].The new 3D design, calculation and manufacturing methods in combination with ultra-high strength concrete (UHPC) off er the potential to revolutionise lightweight concrete construction [1]. The challenge in the production of geometrically complex and high-precision UHPC components lies in formwork construction. As no available waste-free and thus sustainable alternative formwork materials or systems have been identified so far, the research approach was developed to use freely shaped formwork for concrete components using CNC-milled recyclable industrial waxes. The research of this approach towards an applicable non-waste formwork technology was carried out in a joint research project of the Institute for Machine Tools and Production Engineering (IWF) and the Institute of Structural Design (ITE) of the Technical University of Braunschweig. In the following, the main contents of the project, starting with the selection of suitable waxes, the investigation of machinability up to the concreting and subsequent analysis of the formwork and castings are presented and discussed. Basic findings have already been published in 2016 in [2]–[5]. These are partly reproduced here and supplemented with additional information. The main findings of the research project are summarised. Detailed information on the development of non-waste wax formwork technology can be found in the dissertation by Jeldrik Mainka [6], published in 2019

The applying of three-dimensional reconstruction for planning and supporting surgical operations

Аппаратно-программный комплекс для помощи хирургу во время проведения операции,представляет собой систему отображения набора анатомических компьютерных 3D моделей зоны интереса на дисплее в хирургической операционной. Данные анатомические модели получаются в результате предварительной реконструкции на основе сегментации медицинских изображений, таких модальностей как КТ, МРТ, ПЭТ и др. Аппаратно-программный комплекс поддержки проведения хирургического вмешательства включает в себя также систему захвата движения, предназначенную длябесконтактного управления, за сч?т жестов оператора набором анатомических 3D моделей на дисплее. Система позволяет управлять положением набора 3D моделей, их масштабом и прозрачностью отдельных моделей, а также перемещаться между наборами 3D моделей, построенных для различных стадий проведения хирургической операции.Hardware and software system to assist the surgeon during surgery. This is a system for displaying a set ofanatomical 3D computer models of regions of interest on display in the surgery. These anatomical models areobtained by a preliminary reconstruction based segmentation of medical images of such modalities as CT, MRI,PET, etc. Hardware and software system support surgery also includes motion-capture system designed for contactmanagement, through gestures of the operator, a set of 3D anatomical models on display. The system allows tocontrol the position of the set of 3D models, their scale and transparency of individual models and to navigatebetween sets of 3D models for various stages of the surgery