96 research outputs found
Recommended from our members
ReSCon '11, Research Student Conference: Book of Abstracts
The fourth SED Research Student Conference (ReSCon2011) was hosted over three days, 20-22 June 2011, in the Hamilton Centre at Brunel University. The conference consisted of technical presentations, a poster session and social events. which focused on current research being conducted within the School of Engineering and Design by postgraduate research students from the School. The conference is held annually, and ReSCon plays a key role in contributing to research and innovations within the School
Academic Year 2019-2020 Faculty Excellence Showcase, AFIT Graduate School of Engineering & Management
An excerpt from the Dean\u27s Message:
There is no place like the Air Force Institute of Technology (AFIT). There is no academic group like AFITās Graduate School of Engineering and Management. Although we run an educational institution similar to many other institutions of higher learning, we are different and unique because of our defense-focused graduate-research-based academic programs. Our programs are designed to be relevant and responsive to national defense needs. Our programs are aligned with the prevailing priorities of the US Air Force and the US Department of Defense. Our faculty team has the requisite critical mass of service-tested faculty members. The unique composition of pure civilian faculty, military faculty, and service-retired civilian faculty makes AFIT truly unique, unlike any other academic institution anywhere
2018 Faculty Excellence Showcase, AFIT Graduate School of Engineering & Management
Excerpt:
As an academic institution, we strive to meet and exceed the expectations for graduate programs and laud our values and contributions to the academic community. At the same time, we must recognize, appreciate, and promote the unique non-academic values and accomplishments that our faculty team brings to the national defense, which is a priority of the Federal Government. In this respect, through our diverse and multi-faceted contributions, our faculty, as a whole, excel, not only along the metrics of civilian academic expectations, but also along the metrics of military requirements, and national priorities
Precision Agriculture Technology for Crop Farming
This book provides a review of precision agriculture technology development, followed by a presentation of the state-of-the-art and future requirements of precision agriculture technology. It presents different styles of precision agriculture technologies suitable for large scale mechanized farming; highly automated community-based mechanized production; and fully mechanized farming practices commonly seen in emerging economic regions. The book emphasizes the introduction of core technical features of sensing, data processing and interpretation technologies, crop modeling and production control theory, intelligent machinery and field robots for precision agriculture production
Air Force Institute of Technology Research Report 2013
This report summarizes the research activities of the Air Force Institute of Technologyās Graduate School of Engineering and Management. It describes research interests and faculty expertise; lists student theses/dissertations; identifies research sponsors and contributions; and outlines the procedures for contacting the school. Included in the report are: faculty publications, conference presentations, consultations, and funded research projects. Research was conducted in the areas of Aeronautical and Astronautical Engineering, Electrical Engineering and Electro-Optics, Computer Engineering and Computer Science, Systems Engineering and Management, Operational Sciences, Mathematics, Statistics and Engineering Physics
On Random Sampling for Compliance Monitoring in Opportunistic Spectrum Access Networks
In the expanding spectrum marketplace, there has been a long term evolution towards more marketā¬āoriented mechanisms, such as Opportunistic Spectrum Access (OSA), enabled through Cognitive Radio (CR) technology. However, the potential of CR technologies to revolutionize wireless communications, also introduces challenges based upon the potentially nonā¬ādeterministic CR behaviour in the Electrospace. While establishing and enforcing compliance to spectrum etiquette rules are essential to realization of successful OSA networks in the future, there has only been recent increased research activity into enforcement. This dissertation presents novel work on the spectrum monitoring aspect, which is crucial to effective enforcement of OSA. An overview of the challenges faced by current compliance monitoring methods is first presented. A framework is then proposed for the use of random spectral sampling techniques to reduce data collection complexity in wideband sensing scenarios. This approach is recommended as an alternative to Compressed Sensing (CS) techniques for wideband spectral occupancy estimation, which may be difficult to utilize in many practical congested scenarios where compliance monitoring is required. Next, a lowā¬ācost computational approach to online randomized temporal sensing deployment is presented for characterization of temporal spectrum occupancy in cognitive radio scenarios. The random sensing approach is demonstrated and its performance is compared to CSā¬ābased approach for occupancy estimation. A novel frameā¬ābased sampling inversion technique is then presented for cases when it is necessary to track the temporal behaviour of individual CRs or CR networks. Parameters from randomly sampled Physical Layer Convergence Protocol (PLCP) data frames are used to reconstruct occupancy statistics, taking account of missed frames due to sampling design, sensor limitations and frame errors. Finally, investigations into the use of distributed and mobile spectrum sensing to collect spatial diversity to improve the above techniques are presented, for several common monitoring tasks in spectrum enforcement. Specifically, focus is upon techniques for achieving consensus in dynamic topologies such as in mobile sensing scenarios
Analyse et amƩlioration de la qualitƩ de services WEB multimƩdia et leurs mises en oeuvre sur ordinateur et sur FPGA
RĆ©sumĆ© : Les services Web, issus de lāavanceĢe technologique dans le domaine des reĢseaux informatiques et des dispositifs de teĢleĢcommunications portables et fixes, occupent une place primordiale dans la vie quotidienne des gens. La demande croissante sur des services Web multimeĢdia (SWM), en particulier, augmente la charge sur les reĢseaux dāInternet, les fournisseurs de services et les serveurs Web. Cette charge est essentiellement due au fait que les SWM de haute qualiteĢ neĢcessitent des deĢbits de transfert et des tailles de paquets importants. La qualiteĢ de service (par deĢfinition, telle que vue par lāutilisateur) est influenceĢe par plusieurs facteurs de performance, comme le temps de traitement, le deĢlai de propagation, le temps de reĢponse, la reĢsolution dāimages et lāefficaciteĢ de compression.
Le travail deĢcrit dans cette theĢse est motiveĢ par la demande continuellement croissante de nouveaux SWM et le besoin de maintenir et dāameĢliorer la qualiteĢ de ces services. Nous nous inteĢressons tout dāabord aĢ la qualiteĢ de services (QdS) des SWM lorsquāils sont mis en Åuvre sur des ordinateurs, tels que les ordinateurs de bureau ou les portables. Nous commencĢ§ons par eĢtudier les aspects de compatibiliteĢ afin dāobtenir des SWM fonctionnant de manieĢre satisfaisante sur diffeĢrentes plate-formes. Nous eĢtudions ensuite la QdS des SWM lorsquāils sont mis en Åuvre selon deux approches diffeĢrentes, soit le protocole SOAP et le style RESTful. Nous eĢtudions plus particulieĢrement le taux de compression qui est un des facteurs influencĢ§ant la QdS.
ApreĢs avoir consideĢreĢ sous diffeĢrents angles les SWM avec mise en Åuvre sur des ordinateurs, nous nous inteĢressons aĢ la QdS des SWM lorsquāils sont mis en Åuvre sur FPGA. Nous effectuons alors une eĢtude et une mise en Åuvre qui permet dāidentifier les avantages aĢ mettre en Åuvre des SWM sur FPGA.
Les contributions se deĢfinissent en cinq volets comme suit :
1. Nous introduisons des meĢthodes de creĢation, cāest-aĢ-dire conception et mise en Åuvre, de SWM sur des plate-formes logicielles heĢteĢrogeĢnes dans diffeĢrents environnements tels que Windows, OS X et Solaris. Un objectif que nous visons est de proposer une approche permettant dāajouter de nouveaux SWM tout en garantissant la compatibiliteĢ entre les plate-formes, dans le sens ouĢ nous identifions les options nous permettant dāoffrir un ensemble riche et varieĢ de SWM pouvant fonctionner sur les diffeĢrentes plate-formes.
2. Nous identifions une liste de parameĢtres pertinents influencĢ§ant la QdS des SWM mis en Åuvre selon le protocole SOAP et selon le style REST.
3. Nous deĢveloppons un environnement dāanalyse pour quantifier les impacts de chaque parameĢtre identifieĢ sur la QdS de SWM. Pour cela, nous consideĢrons les SWM mis en Åuvre selon le protocole SOAP et aussi selon style REST. Les QdS obtenues avec SOAP et REST sont compareĢes objectivement. Pour faciliter la comparaison, la meĢme gamme dāimages (dans lāanalyse de SWM SOAP) a eĢteĢ reĢutiliseĢe et les meĢmes plate-formes logicielles.
4. Nous deĢveloppons une proceĢdure dāanalyse qui permet de deĢterminer une correĢlation entre la dimension dāune image et le taux de compression adeĢquat. Les reĢsultats obtenus confirment cette contribution propre aĢ cette theĢse qui confirme que le taux de compression peut eĢtre optimiseĢ lorsque les dimensions de lāimage ont la proprieĢteĢ suivante : le rapport entre la longueur et la largeur est eĢgal au nombre dāor connu dans la nature. Trois libraires ont eĢteĢ utiliseĢes aĢ savoir JPEG, JPEG2000 et DjVu.
5. Dans un volet compleĢmentaire aux quatre volets preĢceĢdents, qui concernent les SWM sur ordinateurs, nous eĢtudions ainsi la conception et la mise en Åuvre de SWM sur FPGA. Nous justifions lāoption de FPGA en identifiant ses avantages par rapport aĢ deux autres options : ordinateurs et ASICs. Afin de confirmer plusieurs avantages identifieĢs, un SWM de QdS eĢleveĢe et de haute performance est creĢeĢ sur FPGA, en utilisant des outils de conception gratuits, du code ouvert (open-source) et une meĢthode fondeĢe uniquement sur HDL. Notre approche facilitera lāajout dāautres modules de gestions et dāorchestration de SWM.
6. La mise aĢ jour et lāadaptation du code open-source et de la documentation du module Ethernet IP Core pour la communication entre le FPGA et le port Ethernet sur la carte Nexys3. Ceci a pour effet de faciliter la mise en Åuvre de SWM sur la carte Nexys3. // Abstract : Web services, which are the outcome of the technological advancements in IT networks
and hand-held mobile devices for telecommunications, occupy an important role in our
daily life. The increasing demand on multimedia Web services (MWS), in particular,
augments the load on the Internet, on service providers and Web servers. This load
is mainly due to the fact that the high-quality multimedia Web services necessitate
high data transfer rates and considerable payload sizes. The quality of service (QoS,
by definition as it is perceived by the user) is influenced by several factors, such as
processing time, propagation delay, response time, image resolution and compression
efficacy.
The research work in this thesis is motivated by the persistent demand on new MWS,
and the need to maintain and improve the QoS. Firstly, we focus on the QoS of MWS
when they are implemented on desktop and laptop computers. We start with studying
the compatibility aspects in order to obtain MWS functioning satisfactorily on different
platforms. Secondly, we study the QoS for MWS implemented according to the SOAP
protocol and the RESTful style. In particular, we study the compression rate, which is
one of the pertinent factors influencing the QoS.
Thirdly, after the study of MWS when implemented on computers, we proceed with the
study of QoS of MWS when implemented on hardware, in particular on FPGAs. We
achieved thus comprehensive study and implementations that show and compare the
advantages of MWS on FPGAs.
The contributions of this thesis can be resumed as follows:
1. We introduce methods of design and implementation of MWS on heterogeneous
platforms, such as Windows, OS X and Solaris. One of our objectives is to
propose an approach that facilitates the integration of new MWS while assuring
the compatibility amongst involved platforms. This means that we identify the
options that enable offering a set of rich and various MWS that can run on different
platforms.
2. We determine a list of relevant parameters that influence the QoS of MWS.
3. We build an analysis environment that quantifies the impact of each parameter on
the QoS of MWS implemented on both SOAP protocol and RESTful style. Both
QoS for SOAP and REST are objectively compared. The analysis has been held on
a large scale of different images, which produces a realistic point of view describing
the behaviour of real MWS.
4. We develop an analysis procedure to determine the correlation between the
aspect ratio of an image and its compression ratio. Our results confirm that
the compression ratio can be improved and optimised when the aspect ratio of
iiiiv
an image is close to the golden ratio, which exists in nature. Three libraries of
compression schemes have been used, namely: JPEG, JPEG2000 and DjVu.
5. Complementary to the four contributions mentioned above, which concern the
MWS on computers, we study also the design and implementation of MWS on
FPGA. This is justified by the numerous advantages that are offered by FPGAs,
compared to the other technologies such as computers and ASICs. In order to
highlight the advantages of implementing MWS on FPGA, we developed on FPGA
a MWS of high performance and high level of QoS. To achieve our goal, we utilised
freely available design utilities, open-source code and a method based only on
HDL. This approach is adequate for future extensions and add-on modules for
MWS orchestration
Virtual Reality Applications and Development
Virtual Reality (VR) has existed for many years; however, it has only recently gained wide spread popularity and commercial use. This change comes from the innovations in head mounted displays (HMDs) and from the work of many software engineers making quality user experiences (UX). In this thesis, four areas are explored inside of VR. One area of research is within the use of VR for virtual environments and fire simulations. The second area of research is within the use of VR for eye tracking and medical simulations. The third area of research is within multiplayer development for more immersive collaborative simulations. Finally, the fourth area of research is within the development of typing in 3D for virtual reality. Extending from this final area of research, this thesis details an application that details more practical and granular details about developing for VR and using the real-time development platform, Unity
- ā¦