Eine kurze Einführung zu "Voice over IP" (dem Telefonieren über Datennetze). Es wird ein Überblick über technische Anforderungen und Lösungen geben. Behandelte Gebiete sind Audio-Codecs, das Transportprotokoll RTP sowie die Signalisierungsdienste SIP und H.323.

Der Vortrag zeigt Grundlagen und Möglichkeiten der Programmierung von ATMEL-Mikrocontrollern am Beispiel des ATMega32 (ATMega 644). Der integrierte USART-Baustein wird beispielhaft für Debugging und als Interface für einen Bootloader vorgestellt. Für die Kommunikation im Netz wird ein Ethernetcontroller (ENC28J60) am SPI-Interface angebunden. Am Beispiel der TCP/IP-Implementierung von Ulrich Radig wird die Funktionsweise erläutert. Die Anbindung von Sensoren (z.B. OneWire Temperatursensor) runden den Vortrag ab.

The evolving of the networking application and electronic components are pushing the bandwidth limits in the automotive domain [19]. Consequently, the car manufacturers have begun to produce more complex Electronic Control Units (ECUs) to fulfil the automotive technology evolution. Car manufacturers have used ECUs from different vendors to get the most creative features in cars [19]. These ECUs requires a standard network interface such as Ethernet which can bring significant features such as high bandwidth, low weight and full duplex communication. Nowadays, Ethernet has adapted to apply in the automotive application. Therefore, it has called for a high degree of testing to ensure the safety and interoperability between these ECUs. However, the testing of the Automotive Ethernet is facing many challenges such as finding and solving the issues as early as possible in the development process. Besides that, testing an Automotive Ethernet TCP/IP stack is a complex task, as it required an upper tester to cause the implementation of the device under the test to move to specific states. AUTOSAR has defined a standardised control protocol (Test Stub) to use it as an upper tester for executing the AUTOSAR Acceptance Test (for TCP/IP stack) [6]. This protocol has used for conducting the test cases of the TCP, UDP and IP protocols in AUTOSAR [21] [22] [23]. OPEN Alliance has specified an Automotive Ethernet ECU test specification which covers more protocols than AUTOSAR such as ARP and DHCP [7]. Consequently, potential gaps and issues may arise when using the Test Stub to conduct the test cases of the OPEN Alliance, as it initially defined for conducting the AUTOSAR Acceptance Test. This work presents the evaluation of the Test Stub in context of using it to conduct the OPEN Alliance Automotive Ethernet ECU Test. Furthermore, it will introduce a solution to overcome the potential issues and gaps which may arise after using the Test Stub (defined by AUTOSAR) to conduct the test cases of the OPEN Alliance.

This master thesis presents, examines, designs, implements, and evaluates with respect to energy efficiency a secure and robust VoIP system. This system utilizes a Session Initiation Protocol (SIP) infrastructure assisted by a cloud service, specifically focusing on small to medium sized enterprises (SME) and homes. This research focuses on using inexpensive, flexible, commodity embedded hardware (specifically a Linksys WRT54GL wireless router for the local site with a customized operating system, specifically DD-WRT). The idea is to reduce the local site's power consumption to very low levels by examining which functions can be done in a cloud service rather than at the local site. The thesis presents the design of a low-power IP telephony system for the local site and the cloud site. A number of different usage scenarios and desirable features are described. The methodology for conducting a set of experiments is defined to perform stress-testing and to evaluate the low- power IP telephony system's design. The experiments concern the overall power consumption of the local site under various configurations, the VPN link's call capacity, the QoS metrics for the VoIP calls, the session request delay (SRD) and the registration request delay (RRD). The results from these experiments show that there is a potential for significant power savings when using the proposed design for an IP telephony system. / Detta examensarbete presenterar, undersöker, utformar, implementerar, och försöker att utvärdera ett säkert och robust VoIP-system med energieffektivitet. Detta system använder en Session Initiation Protocol (SIP)-infrastruktur med hjälp av en molntjänst med särskild inriktning på, små, och medelstora företag (SME) och hemmanvändare. Denna forskning fokuserar att använda en prisvärt, billig, flexibel, med program inbyggd hårdvara (speciellt en Linksys WRT54GL trådlös router för den lokala platsen med ett anpassat operativsystem DD-WRT). Tanken är att minska energiförbrukningen på, den lokala platsen till mycket låga nivåer genom att undersöka vilka funktioner, som kan köras på, ett molntjnst snarare än på, den lokala platsen. Avhandlingen presenterar utformningen av ett IP-telefonisystem på, den lokala platsen med ett lågt strömbehov och på, molntjänsten. Ett antal olika användningsförhållanden och önskvärda egenskaper är beskrivna. Metodiken för att genomföra en rad experiment definieras för att utföra stresstester och för att utvärdera designen av IP-telefonisystem med ett lågt effektbehov. I försöken experimenteras den totala energiförbrukningen av den lokala platsen under olika konfigurationer, VPN-länkens samtalskapacitet, QoS-mätning för VoIP-samtal, Session Request Delay (SRD) och Registration Request Delay (RRD). Resultaten från dessa experiment visar att det finns en potential för betydande energibesparing när du använder den föreslagna designen för en IP-telefoni system.

Today, the telecommunication world is focused on mobility. This is popular because since the 1990s most people have integrated their mobile phones into their life. A new factor is the rise of the voice over IP(VoIP) technology, with VoIP over Wireless LANs (WLANs) as the clear next growth area for mobile communications. The purpose of this thesis was to understand how to save power based upon changing when some operations are performed in a VoIP client. In order to do this, we decided to port minisip to an HP iPAQ 5500 Personal Digital Assistant (PDA), in order to explore some of the issues of running such a client on a PDA - due to its constraints with regard to storage, processing power, and battery power. Minisip is a SIP open source user agent running on Linux and Windows. This thesis builds upon earlier theses which showed that minisip can offer a secure communications platform with the latest functions which are desired in a mobile personal VoIP system. However, most of these earlier theses utilized desktop, laptop, or server based system, i.e., with few resources constrains. The focus of this thesis was to examine the case of a highly constrained user platform such as an iPAQ. / Dagens telekommunikationssystem fokuserar på mobilitet. Detta har blivit populärt under 90-talet då mobilitet blev naturligt integrerad i människans vardagliga liv i form av exempelvis mobiltelefoner. Voice over IP (VoIP) har blivit en stor del av dagen teknik där trådlösa system Wireless LANs (WLANs) har blivit en större del av mobilkommunikation. Målet med denna rapport är att förstå hur strömförbrukningen kan minimeras genom att utföra vissa operationer med hjälp av en VoIP-klient. För att åstadkomma detta porterade vi minisip, en SIP agent som är baserad på öppen källkod och körs på Linux och Windows, till en HP iPAQ 5500, en så kallad Personal Digital Assistant (PDA). Vi valde PDAn för att kunna utforska de begränsningar den medför i form av lagringsutrymme, processorkapacitet, och batteri. Denna rapport bygger vidare på tidigare rapporter som visar att minisip kan erbjuda en säker kommunikationsplattform med de senaste funktionerna som önskas i mobila VoIPsystem. De flesta av dessa tidigare rapporter baseras på system med få begränsningar rörande resurser såsom stationära- eller bärbara datorer samt serverbaserade system. Denna rapports fokus är att utforska detta fall i en miljö med större begränsningar på resurser som till exempel en iPAQ.

The thesis aims to implement different digital filters such as finite impulse response (FIR), infinite impulse response (IIR) and cascade integrator comb (CIC) on the field-programmable gate array (FPGA) development board using hardware description language (VHDL). To this purpose, Intel’s systems integration tool Platform designer is used to convert the implementation to an IP core. The implemented FIR and IIR filters include different filter types such as lowpass, highpass, bandpass and bandstop. All the filters have a pipeline architecture as well as adjustable parameters such as filter order, frequency specifications and resolution. The coefficients of the filters are calculated according to the user's specifications. The calculated coefficients are verified using simulation. Furthermore the IP has been validated on hardware by the FPGA board MAX DE-10 lite. The IP is also analyzed regarding timing and power consumtion with good results. FIR filters of different types have been implemented and tested up to 501 taps with a coefficient width of 24 bits, which covered just below 50% of the available logic gates on the MAX 10-DE lite board with 50000 gates in total. The FIR filters have an option to be used with a Kaiser window with a maximum tap level of 51. Different IIR filters have also been implemented and tested on the hardware. However, the results have shown that the IIR filters do not perform so well, especially those of order higher than 6. One of the main reasons for this is the overflow caused by instability of the IIR.

Tesis

Rapid advances in integration technology have tremendously increased the design complexity of very large scale integrated (VLSI) circuits, necessitating robust optimization techniques in many stages of VLSI design. A genetic algorithm (GA) is a stochastic optimization technique that uses principles derived from the evolutionary process in nature. In this work, genetic algorithms are used to alleviate the hardware design process of VLSI application specific integrated circuits (ASICs) and reconfigurable hardware. VLSI ASIC design suffers from high design complexity and a large number of optimization objectives requiring hierarchical design approaches and multi-objective optimization techniques. The floorplanning stage of the design cycle becomes highly important in hierarchical design methods. In this work, a multi-objective genetic algorithm based floorplanner has been developed with novel crossover operators to address the multi-objective floorplanning problem for VLSI ASICs. The genetic floorplanner achieves significant wirelength savings (>19% on average) with little or no increase in area ( < 3% penalty) over previous floorplanners that perform simultaneous area and wirelength minimization. Hardware implementation of genetic algorithms is gaining importance because of their proven effectiveness as optimization engines for real-time applications. Earlier hardware implementations suffer from major drawbacks such as absence of GA parameter programmability, rigid pre-defined system architecture, and lack of support for multiple fitness functions. A compact IP core that implements a general purpose GA engine has been designed to realize evolvable hardware in field programmable gate array devices. The designed GA core achieved a speedup of around 5.16x over an analogous software implementation. Novel reconfigurable analog architectures have been proposed to realize extreme environment analog electronics. In this work, a digital framework has been developed to realize self reconfigurable analog arrays (SRAA) where genetic algorithms are used to evolve the required analog functionality and compensate performance degradation in extreme environments. The framework supports two methods of compensation, namely, model based lookup and genetic algorithm based compensation and is scalable in terms of the number of fitness evaluation modules. The entire framework has been implemented as a digital ASIC in a leading industrystrength silicon-on-insulator (SOI) technology to obtain high performance and a small form factor.

No description available.

Violence can be handled in a variety of ways across a wide variety of film genres and specific grasps of genres. The goal of this thesis is to explore the different functions of violence in films and then show how different is the acceptance of violence by Western film critics, ie journalists, in the same genre with similar motivations of the main characters, but with a slightly different approach of these characters to the use of violence. In the theoretical part I will describe the terms of review, criticism, film and at the same time the function of violence in films across genres. The practical part will then show how the concept of violence and its function may differ even within one larger genre, although the motivations of the main characters may sometimes be similar. Certain parallels as well as differences in the use and function of violence will be discussed on the example of selected scenes from two action film series Ip Man and Rambo. Subsequently, the reactions to the manifestations of violence by film critics will be analyzed and in the end it will be assessed whether the critics reacted to the processing of violence at all, how they reacted to it and what generally follows from the critics' approach to various possibilities on depicting violence. The partial goal of the thesis will...