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Monday 30 November 2009

Its official!

  • So its official now. And this email will explain how (:

Hi!

On Wednesday the 2nd of December at 9 o'clock (9:00~12:00) we'll have three MSc. Thesis defense's in 3235A at Campus Gräsvik. Below, you will find the thesis titles and abstracts.

Welcome!

/Patrik Arlos


Performance Of 3G data Services Over Mobile Network in Sweden, Ravichandra Kommalapati.

The emerging technologies in the field of telecommunications enable us to access high speed data services through mobile handsets and portable modems over the mobile networks. The recent statistics also shows the use of mobile broadband services are increasing and gaining popularity.

In this thesis we have investigated the impact of packet size and data rate on one way delay and packet loss in operational 3G mobile networks through network level measurements. To collect the network level traces an experimental testbed is developed. For accurate measurement Endace DAG cards together with GPS synchronization is implemented. Results were gathered from three different commercial mobile operators in Sweden. From the results it was concluded that the combination of maximum packet size and data rate resulted in minimum one way delay. It is also observed within the big packet size category, that the percentage of packet loss is less as compared to the smaller packer sizes. Such findings may prove e±cient for application developers to make the post of the UMTS network conditions.


Bitrate Analysis On First Person Shooter Games, Bandaru Lokeswara Rao.

Multiplayer games are prominent now a days. In recent years real time multiplayer networked gaming has grown in popularity due to exciting challenges posed in by competing with human opponents. One of the types of multi player games is First Person shooter games. FPS games are becoming popular predominantly over wired networks. In FPS games delay, bitrate and inter packet arrival times has major roles because they determine who wins and loses the game.

This thesis investigates the behavior of bitrate at different parts in the network and at different time scales, which involves analyzing of bitrate traces in each relevant stream of the disturbed network in the game i.e. identification of when the disturbance occurred in the traces, identification of what IP that was disturbed and simple statistics are made at different locations of the stream at same sample frequency. Finally we analyze the behavior of bitrate at different parts of the network and with the help of the statistics made out of them, we compare to the user experience. How the user felt at each and every second while playing the game and how experienced he is in playing the games is been considered and compared with the data which was already collected before in the Dream Hack winter 2007, Tele Communications department of Blekinge Institute of Technology, Sweden.This results thus suggests at which bit rate the network should flow in order to satisfy the end user, as the quality of experience that counts at the last.

Mapping of User Quality-of-Experience to Application Perceived Performance for Web Application, Ashfaq Ahmad Shinwary.

Data services prove to be integral part of the Internet today of which web browsing stands out to be the popular user activity. User perceived quality of web browsing can be affected by delays in the network that can result in higher application download times. Quality of Experience is of highly subjective nature. Majority of the work done is this regard managed to map network metrics to Quality of Experience but the relationship between user perception and application quality was always in vague.

In this thesis work, an effort has been made to map applications metrics to Quality of Experience. A subjective analysis on how the user takes into account the domain of web browsing has been carried out. For this purpose a testbed was developed at Blekinge Institute of Technology on which different users were tested. Specific sequences of delays were introduced on the network which resulted in desired application download times. Conclusions were made by stating that user experience in web browsing is affected by application download times. It was found that user Quality of Experience ratings for download times of more than 3 seconds deteriorated which eventually leads to the conclusion that a user is not in favor of tolerating application download times of more than 3 seconds. Furthermore there exists an exponential relationship between Quality of Experience and application download times.

Patrik Arlos,
Ph.D Telecommunications systems,
School of Computing,
Blekinge Institute of Technology.
Karlskrona, Sweden.

Tuesday 24 November 2009

LaTeX Figures

One of the biggest problem that has given me a really hard time while using LaTeX is the use of figures. Most of my figures always were MS Visio drawings. As LaTeX accepts figures in PS or EPS formats, so the normal conversion methods mostly resulted in poor image quality. Googling it I was able to find there are numerous methods. some long, some hectic; most of which didn't worked for me. So here I would be telling you a pretty simple method for conversion of MS Visio images to standard PS formats that can result in high qulaity images for you to use in your LaTeX document provided you have a professional Adobe Reader (any version) and the MS office SAVE AS PDF plugin. Just follow these steps.
  1. When you Visio drawing is ready, make sure the page setting is as follows. Goto FILE> PAGE SETUP> PAGE SIZE TAB> there make sure the check box SIZE FIT TO DRAWING CONTENTS is enabled.
  2. Make sure you have the Visio to PDF plugin installed. You can get it from http://www.microsoft.com/downloads/details.aspx?FamilyId=F1FC413C-6D89-4F15-991B-63B07BA5F2E5&displaylang=en
  3. Once you have the plugin installed. Goto File and click PUBLISH AS PDF or XPS.
  4. Now open the PDF file you just created. Once the drawing is opened, saves this as a PS by clicking FILE> SAVE AS and from file format select POST SCRIPT (PS).
  5. You are done and ready to use the generated PS image in your LaTeX document (:

PS: Always use Enhanced Metafile (EMF) images in your MS WORLD/POWERPOINT documents as they give you a petty high quality resolution.