28 research outputs found
Design, analysis, and experiment on multiple servers technology for video-on-demand service in distributed networks
Master'sMASTER OF ENGINEERIN
Multimedia in mobile networks: Streaming techniques, optimization and User Experience
1.UMTS overview and User Experience
2.Streaming Service & Streaming Platform
3.Quality of Service
4.Mpeg-4
5.Test Methodology & testing architecture
6.Conclusion
Effective design, configuration, and use of digital CCTV
It is estimated that there are five million CCTV cameras in use today. CCTV is used by a wide range of
organisations and for an increasing number of purposes. Despite this, there has been little research to
establish whether these systems are fit for purpose. This thesis takes a socio-technical approach to
determine whether CCTV is effective, and if not, how it could be made more effective. Humancomputer
interaction (HCI) knowledge and methods have been applied to improve this understanding
and what is needed to make CCTV effective; this was achieved in an extensive field study and two
experiments. In Study 1, contextual inquiry was used to identify the security goals, tasks, technology
and factors which affected operator performance and the causes at 14 security control rooms. The
findings revealed a number of factors which interfered with task performance, such as: poor camera
positioning, ineffective workstation setups, difficulty in locating scenes, and the use of low-quality
CCTV recordings.
The impact of different levels of video quality on identification and detection performance was
assessed in two experiments using a task-focused methodology. In Study 2, 80 participants identified
64 face images taken from four spatially compressed video conditions (32, 52, 72, and 92 Kbps). At a
bit rate quality of 52 Kbps (MPEG-4), the number of faces correctly identified reached significance. In
Study 3, 80 participants each detected 32 events from four frame rate CCTV video conditions (1, 5, 8,
and 12 fps). Below 8 frames per second, correct detections and task confidence ratings decreased
significantly.
These field and empirical research findings are presented in a framework using a typical CCTV
deployment scenario, which has been validated through an expert review. The contributions and
limitations of this thesis are reviewed, and suggestions for how the framework should be further
developed are provided
A basic web-based distance education model
Thesis (Master)--Izmir Institute of Technology, Computer Engineering, Izmir, 2005Includes bibliographical references (leaves: 147)Text in English; Abstract: Turkish and Englishxv, 201 leavesDuring the recent years, the rapid growth of the Web and multimedia technologies urged a shift of Computer-Based Educational Technology towards the Web. In the leading universities of the developed countries, studies on Web-Based Education have started and in an increasing manner are going strong. In the last few years, the leading universities of Turkey are also greatly interested in Web-Based Education and have started their re-structuring accordingly.The goal of this study is to design a basic model to be utilized by a university aiming to offer web-based distance education. In achieving this; by the use of system approach, a model comprising of three subsystems, namely system analysis, system design and evaluation&control, working in coordination with each other, has been tried to be proposed. There may be only one missing point of this study, that is; since preparing a lesson or program according to this model was not foreseen in this thesis, the effectiveness evaluations suggested in the evaluation&control subsystem could not be realized. It is recommended to realize such an evaluation in a further study to make it possible to reveal the effectiveness of web-based education by preparing a lesson or program according to this model.On the other hand, a survey has been conducted in Turkey in some of the universities either offering web-based education or are interested in studies in this field.The aim of this survey is to analyze from system design point of view the studies carried out in our universities on this matter and to get a picture of the existing situation.The directed questions aiming this were prepared by taking into consideration of the three stages of system design subsystem, i.e. administrative design, educational design, and technological design. It is intended for the result of this survey to shed light to the new-coming institutions in this field. As a matter of fact, each stage of this subsystem is a survey item itself and should be researched one by one in other studies.Furthermore, for individuals interested in distance education and web-based distance education and for people newly involved in this matter, this thesis is intended to be a reference material and to serve this purpose the sections are prepared containing the basic information accordingly. Nevertheless, since most of the information regarding system design are prepared without taking into consideration the disabled people, the relevant information are not complete. In another study, the offering of the web-based education to the disabled people, especially for deaf, hard of hearing or speech impaired, and blind students, has to be investigated.Finally, in this thesis the proposed model for the Web-Based Distance Education, as being a basic and conceptual model, has a flexible structure; i.e., suitable for all the institutions and establishments intending to offer the web-based education.What is important here, is to exploit the potential sources within the institution that will display the required systematic approach
Multimedia presentation authoring and browsing in multimedia database systems
The purpose of this study was to design and implement multimedia presentation authoring and browsing in multimedia database systems, based on a two-tier client/server architecture.
The major approaches included: (i) Build a client/server multimedia presentation authoring and browsing environment; (ii) Allow query-by-image image retrieval and domain-based browsing through the User Datagram Protocol (UDP) between the Java socket at the client and the Unix socket at the server; (iii) Allow the multimedia presentation authoring by unifying the temporal, spatial and spatio-temporal relations among various media items into Multimedia Augmented Transition Network (MATN) model; (iv) Support the user interaction during the authoring process; (v) Visualize the presentation based on the created MATN models.
As a result, this methodology provided users a flexible environment for heterogeneous media data retrieval and multimedia presentation authoring in multimedia database systems
On the Development of Real-Time Multi-User Web Applications
With the increasing popularity of the World Wide Web (WWW), end-user applications are moving from desktop to the browser. Web applications have several benefits over native applications: web applications have worldwide availability for any browsing capable device without prior installations. In addition, web applications are easy to distribute and update – once deployed, a web application is instantly available worldwide and further modifications to the system are propagated automatically. The current trend seems to be that web applications are offering collaboration, social connections, and user to user interactions as key features. This can be seen, for example, in the popularity of Facebook, Flickr, and Twitter.
Despite all the benefits of the Web, web applications are suffering from the shortcomings in underlying technologies. The Web is strongly rooted in information sharing, and the current technical solutions isolate users rather than make them aware of each other. Since the data cannot be pushed from server to a client, the client must always initiate the communication, which causes a considerable impediment for real-time multi-user web applications, like online chats that have several concurrent users continuously interacting with each other. For such systems, it would be practical if the server could push messages to clients. As a further obstacle, most web application frameworks isolate users in their private sessions that only interact indirectly via the database.
This main contribution of this thesis is to make the development of real-time multi-user web applications easier. We elaborate on the difficulties in implementation and design and introduce methods of circumventing them. The main argument is that the Web, the available technology stack, and the frameworks are difficult to use for developing real-time multi-user web applications. However, by selecting the proper approach, the problems can be solved.
In this thesis, we have divided the frameworks in groups based on how they make separation of concerns between the client and the server. The separation is important as it determines the thickness of the client and thus where to locate the business logic and the application state. In addition, it has effect on the synchronization of the state between the clients. To collect experiences and for backing up our assumptions, we have implemented real-time multi-user web applications for several frameworks and studied how the frameworks should be used for enabling real-time multi-user application development
Student Digital Piracy In The Florida State University System:an Exploratory Study On Its Infrastructural Effects
Digital piracy is a problem that may never disappear from society. Through readily available resources such as those found in a university, students will always have access to illegal goods. While piracy is a global phenomenon, an institution\u27s resources combined with the typical college student\u27s lack of funds makes it more lucrative. Students use a number of methods to justify their actions ranging from previewing media to bringing justice to a corrupt company. While trying to understand the mindset of pirates is one route to deal with piracy, corporations attempted to alleviate the situation using added software encoding. These messages are not always effective, and in some cases caused further damage to consumer morale. Furthermore, students such as Joel Tenenbaum, who continued to pirate music despite warnings from his parents and the recording industry, exemplify the type of person that is unfazed by legal threats, leading to a question of ethics. Students may not feel that downloading is stealing despite numerous warnings from the Digital Millennium Copyright Act and other major media organizations. The predominant solution used by universities involves monitoring the students\u27 network connection to detect Peer-to-Peer (P2P) connections or other connections that involve the transferring of copyrighted goods. Unfortunately, the current tools contain flaws that a crafty student may easily circumvent, undermining any attempts a university\u27s IT department may use to deter piracy. This study explored the nature of piracy prevention tools used by IT departments in the Florida State University System in order to determine their relative effectiveness. The study also looked into the opinions of the Information Security Officer in terms of alternative piracy prevention techniques that do not involve legal action and monitoring. It was found that most institutions do not use a formal piece of software that monitors for infringing data. They also stated that while their current techniques can do its required task, it was not perfected to a point where it could run autonomously. Furthermore, institutions agreed that students lack proper ethics and concern over the matter of copyright, but were not fully convinced that other preventions methods would be effective. The study ultimately considered monitoring techniques a short-term solution and that more research should be put into finding long-term solutions. It also implied that IT departments should be better funded in order to keep up with the technological gap
Peer-to-peer-based file-sharing beyond the dichotomy of 'downloading is theft' vs. 'information wants to be free': How Swedish file-sharers motivate their action
This thesis aims to offer a comprehensive analysis of peer-to-peer based file-sharing by focusing on the discourses about use, agency and motivation involved, and how they interrelate with the infrastructural properties of file-sharing.
Peer-to-peer-based file-sharing is here defined as the unrestricted duplication of digitised media content between autonomous end nodes on the Internet. It has become an extremely popular pastime, largely involving music, film, games and other media which is copied without the permission of the copyright holders. Due to its illegality, the popular understanding of the phenomenon tends to overstate its conflictual elements, framing it within a legalistic 'copyfight'. This is most markedly manifested in the dichotomised image of file-sharers as 'pirates' allegedly opposed to the entertainment industry.
The thesis is an attempt to counter this dichotomy by using a more heterodox synthesis of perspectives, aiming to assimilate the phenomenon's complex intermingling of technological, infrastructural, economic and political factors. The geographic context of this study is Sweden, a country characterised by early broadband penetration and subsequently widespread unrestricted file-sharing, paralleled by a lively and well-informed public debate. This gives geographic specificity and further context to the file sharers' own justificatory discourses, serving to highlight and problematise some principal assumptions about the phenomenon. The thesis thus serves as a geographically contained case study which will have analytical implications outside of its immediate local context, and as an inquiry into two aspects of file-sharer argumentation: the ontological understandings of digital technology and the notion of agency. These, in turn, relate to particular forms of sociality in late modernity. Although the agencies and normative forces involved are innumerable, controversies about agency tend to order themselves in a more comprehensive way, as they are appropriated discursively. The invocation to agency that is found in the justificatory discourses - both in the public debate and among individual respondents - thus allows for a more productive and critically attentive understanding of the phenomenon than previously
Framework for supporting previewing and VCR operations in a low bandwidth environment
We propose a novel delivery mechanism called 2-Phase Service Model to deliver video data to home users connected to the Internet through a low-bandwidth device such as a modem. In our scheme, non-adjacent fragments of the requested video file are first downloaded to the client during Initialization Phase. The missing fragments are transmitted to the client as the video is being played out, using a novel pipelining technique. This scheme offers several benefits as follows. First, it allows the user to perform a quick preview through the video with minimal delay. Second, it naturally supports VCR functionality with almost no delay as demonstrated by the simulation results shown in the paper. Finally, our mathematical analysis shows that despite the desirable features it offers, 2-Phase Service Model does not incur any more initialization delay than that of the conventional pipelining technique