Bachelor and Master Theses

List of theses available for opponentship



List of theses available for opponentship

For the presentations on September 21 and 22, 2017

DVA428

Analysis of Time-related Properties in Real-time Data Aggregation Design

Xiaoxiang Hu

Advisor: Simin Cai

Examiner: Dag Nystrom


Abstract:

Data aggregation is extensively used in data management systems nowadays. Based on a data aggregation taxonomy named DAGGTAX, we propose an analytic process to evaluate the run-time platform and time-related parameters of data aggregation processes in a real-time system design, which can help designers to eliminate infeasible design decisions at early stage. The process for data aggregation design and analysis mainly includes the following steps. Firstly, we try to specify the variation of the platform and DAP by figuring out the features of the system and time-related parameters respectively. Then, the user can apply the analytic method for feasibility analysis by schedulability analysis techniques. If there are no infeasibilities found in the process, then the design can be finished. If not, the design must be altered from the run-time platform and DAP design stage, then the schedulability analysis will be applied again for the revised design until all the infeasibilities are fixed. In order to allow designers to do feasibility analysis, we propose a feature model of the run-time platform and a transferring method based on schedulability analysis to transfer the data aggregation design into task model. In the end of the paper, a case study which applies the analytic process to analyze the architecture design of an environmental monitoring sensor network will be presented as an example of our research.


Link to the thesis:

http://www.idt.mdh.se/examensarbete/index.php?choice=show&id=2005

*******************************************************************************


DVA501

Continuous Deployment for Complex Software Intensive Industrial Systems

Zulqarnain Haider

Advisor: Antonio Cicchetti

Examiner: Radu Dobrin


Abstract:

Processes to develop and deliver software have been evolved over the years. One of the primary motivations of this evolution, is gaining the benefits of shorter time-to-market. Continuous deployment is a recent trend to deploy software to the customers automatically and in continuous fashion. Organizations adopting this trend could reach the customers faster through quick deliveries and improve the quality and productivity of the delivered product by an early feedback, and hence achieve increased customer satisfaction. Complex software intensive industrial systems are large-scale, distributed over heterogeneous platforms and interact with several sensors and actuators. Enabling continuous deployment for these industrial systems needs a stable deployment process able to cope with domain specific requirements and challenges. Notably, the required quality attributes of the deployed software product as well as the challenges introduced by the customer-specific nature of the domain. In this thesis, we formalize continuous deployment for industrial systems by identifying the main factors of an appropriate deployment process. In particular, we investigate high-level requirements, required quality attributes of the software product, and challenges in the deployment. Based on this, we propose a continuous deployment pipeline and a set of activities incorporated in the stages of the pipeline, in particular the deployment and post-deployment stages. Moreover, we suggest automation support for the activities to both shorten the delivery time and to preserve repeatability and reliability of the deployment process. The aim of such a process is to maintain the quality attributes of the deployed software. We perform a case study to validate the proposed model by implementing a prototype in an industrial system.


Link to the thesis:

http://www.idt.mdh.se/examensarbete/index.php?choice=show&lang=en&id=2109

*******************************************************************************


DVA501

Re-engineering sequential software to introduce parallelization

Andreas Granholm

Advisors: Federico Ciccozzi and Masoud Daneshtalab

Examiner: Antonio Cicchetti


Abstract:

In the quest for additional computational power to provide higher software performance, industry have shifted to multi-core processing units. At the same time, many existing applications still contain sequential software; in these cases, multi-core processors would not deeply improve performances and in general would be under-utilized since software running on top of them are not conceived to exploit parallelization. In this thesis we aim at providing a way to increase the performance of existing sequential software through parallelization and at the same time minimizing the cost of the parallelization effort. The contribution of this thesis is a generic parallelization method for introducing parallelization into sequential software using multi-core CPUs and GPUs. As a proof-of-concept we ran an experiment in industrial settings by applying the proposed parallelization method to an existing industrial system running sequential code. Additionally, we compare the method we propose to existing methods for parallelization.


Link to the thesis:

http://www.idt.mdh.se/examensarbete/index.php?choice=show&id=2110

*******************************************************************************


DVA502

ADAPTIVE AUTONOMY WITH UNRELIABLE COMMUNICATION

Ragnar Moberg

Advisor: Fredrik Ekstrand

Examiner: Baran Curuklu


Abstract:

For underwater robotics there exists severe constraints regarding wireless bandwidth in the kilobits range. This makes a centralised approach to high-level mission management possibly less than ideal due to inherent delays and possible temporary incompleteness in data during decision making. This thesis aims to propose, implement (in ROS) and test a distributed approach. An auction based method for task assignment was being used, as well as a Pagerank based approach that models a trust based hierarchy between autonomous agents inferred from information exchange, in order to enforce decision conformity. Simulations where carried out using UWsim and a custom made bandwidth limiter for ROS. It was concluded that the Pagerank based algorithm managed to uphold conformity and solve conflicts during network slowdown but did not always lead to the correct decisions being enforced.


Link to the thesis: -


*******************************************************************************


DVA503

Towards hardware accelerated rectification of high speed stereo image streams

Sudhangathan Bankarusamy

Advisor: Carl Ahlberg

Examiner: Mikael Ekstrom


Abstract:

The process of combining two views of a scene in order to obtain depth information is called stereo vision. When the same is done using a computer it is then called computer stereo vision. Stereo vision is used in robotic application where depth of an object plays a role. Two cameras mounted on a rig is called a stereo camera system. Such a system is able to capture two views and enable robotic application to use the depth information to complete tasks. Anomalies are bound to occur in such a stereo rig, when both the cameras are not parallel to each other. Mounting of the cameras on a rig accurately has physical alignment limitations. Images taken from such a rig has inaccurate depth information and has to be rectified. Therefore rectification is a pre-requisite to computer stereo vision. One such a stereo rig used in this thesis is the GIMME2 stereo camera system. The system has two 10 mega-pixel cameras with on-board FPGA, RAM, processor running Linux operating system, multiple Ethernet ports and an SD card feature amongst others. Stereo rectification on memory constrained hardware is a challenging task as the process itself requires both the images to be stored in the memory. The FPGA on the GIMME2 systems must be used in order to achieve the best possible speed. Programming a system that does not have a display and for used for a specific purpose is called embedded programming. The purpose of this system is distance estimation and working with such a system falls in the Embedded Systems program. This thesis presents a method that makes rectification a step ahead for this particular system. The functionality of the algorithm is shown in MATLAB and using VHDL and is compared to available tools and systems.


Link to the thesis:

http://www.idt.mdh.se/examensarbete/index.php?choice=show&id=1745

*******************************************************************************


DVA503

MODELLING AND ANALYSING COLLABORATING HEAVY MACHINES

Jayasoorya Jayanthi Surendran Nair

Advisors: Marjan Sirjani and Stephan Baumgart

Examiner: Cristina Seceneleau


Abstract:

Cyber Physical Systems (CPS) consist of embedded computers and networks for controlling and monitoring the physical processes associated with it. In practice, these systems are complex in nature. Also most of the CPS systems handle concurrent and real time operations and they aremostly distributed in architecture. Suitable analysis techniques needs to be used in order to design and develop a CPS system. Formal verification is a branch of software engineering which is used to verify the correctness of a design. Model checking is one technique used in formal verification,where a formal model of the real system is developed. This model is used for verify the correctness of the system design against its the specified requirements. For model checking, a formal modeland a formal specification language is required. There are several formalism available to represent concurrent distributed systems such as Petrinets, Actor models etc. Actor models are suitable for modeling the functional behaviour of distributed and asynchronous systems. If formal verification support could be in corporated with an actor model, it shall be beneficial in analyzing cyber physical systems. In this thesis, we use an actor based modelling language which is supported by formal semantics to analyze a complex cyber physical system. This study aims to analyze the distributed nature and concurrent behaviour of the system and not on timing constraints. The system selected for this study is a safety critical system which consists of several autonomous machines which are operating in a fleet manner carrying out concurrent operations at a site. We also analyze the distributed design architecture of autonomous machine individually. The design implementation of the system is developed in a Robot Operating System and the actor based modelling language used for developing the models is ’Reactive Objects Language’ (Rebeca). Thus major tasks of the study includes understanding the ROS based system, transformation of ROS elements to Rebeca models and verification of system specific properties. Study outcomes include identification of few mapping patterns between ROS and Rebeca. During this process a reusable algorithm describing the procedure of transforming any ROS code to Rebeca model was developed. Our study results hence proves the potential of Rebeca in verifying real robotic applications.


Link to the thesis:

http://www.idt.mdh.se/examensarbete/index.php?choice=show&id=1992




  • Mälardalen University |
  • Box 883 |
  • 721 23 Västerås/Eskilstuna |
  • 021-101300, 016-153600 |
  • webmaster |
  • Latest update: 2017.10.14