6162473
The Effects of Mobility and Redundancy on Wireless Video Streaming over MANETs
This study examines the extended use of different coding schemes (Scalable vs. Multiple Description or MD) in different video formats (MPEG vs. Motion JPEG or MJPEG) in a Mobile Ad Hoc Network (MANET) environment and proposes a set of redundancy solutions at different coding levels. Simulations and analysis demonstrate and explain the relationship among the coding schemes, video formats, level and amount of redundancy, mobility of mobile devices, CPU load and battery life and frame loss rate at the receiver side. Finally, two practical scenarios are used to illustrate these findings and proposed solutions.
17397024
Multi-level secure video streaming over SRTP
In this paper, we propose a set of solutions to four different levels on data selection for encrypting Motion JPEG video frames over SRTP. These solutions are based on our intensive analysis of the JPEG image compression procedure. We select the most important data which contains most information of an image for encryption; in consequence provide a set of balances between security and computation for different hardware environments. Extensive experiments are conducted and performance data has been analyzed to evaluate the proposed solutions. Results show that these solutions are well suited in different scenarios with various computation power and security requirements.
16274066
Density-based multipath secure communication over mobile ad hoc networks
Security is a critical issue in mobile ad hoc networks (MANETs), where mobile nodes communicate with each other over relatively unreliable wireless links with no fixed infrastructure. One example of this occurs on battle fields, where soldiers often wear cameras and wireless mobile devices to send or receive images/video of different angles or locations in order to obtain better observation of the area. Such an environment could be highly insecure since an enemy could place devices to eavesdrop on or compromise the soldier nodes. In this paper, we consider a case where time sensitive multimedia is sent using multiple paths which can make better use of load balancing strategies, increase bandwidth and save node energy. However, an enemy node could listen in on more than one path at the same time, allowing it to collect sufficient shares of an image or video frame to recover the image. Our proposed algorithm is based on a quantitative analysis of security to protect against such multi-path eavesdropping. We prove that our algorithm can achieve better level of security by detouring traffic via paths without or with less vulnerable areas at the same amount of redundancy. On the other hand, we also prove, using simulation results and mathematical derivation, our algorithm can provide much more redundancy for better multimedia quality purpose while at the same time guaranteeing the same level of security.
14606163
Gene intrusion on a society of Hill-Climbers
In this paper, a new algorithm of Gene Intrusion on a Society of Hill-Climbers (GI-SoHC) is introduced. In GI-SoHC, the genes which contribute most to the best fitness of the best climber in each generation are selected and inserted to other climbers for replacing their own genes, such that the society can have faster climbing speed and better climbing locations.The experiment results show that with Gene Intrusion, climbers generally and averagely perform better in that they climb more quickly than the original Historical Society of Hill-Climbers, especially in the early stage of the climbing process.
11780042
A Multi-Level Index Structure for Video Databases
Several salient object-based data models have been proposed to model the video data, however, none of them proposed an index structure to handle the salient object-based queries efficiently. There are several indexing schemes that have been proposed for spatio-temporal relationships among objects and they are used to optimize timestamp and interval queries, which are rarely used in video database. Moreover, these index structures are designed without consideration of the granularity levels of constraints in salient objects and the characteristics of the video data. In this paper, we propose a multi-level index structure to efficiently handle the salient object-based quires with different levels of constraints. The characteristics of video data are also captured in the second level of the index structure designed to reduce the storage requirement.
1494369
Incorporating Gesture and Gaze into Multimodal Models of Human-to-Human Communication
Structural information in language is important for obtaining a better understanding of a human communication (e.g., sentence segmentation, speaker turns, and topic segmentation). Human communication involves a variety of multimodal behaviors that signal both propositional content and structure, e.g., gesture, gaze, and body posture. These non-verbal signals have tight temporal and semantic links to spoken content. In my thesis, I am working on incorporating non-verbal cues into a multimodal model to better predict the structural events to further improve the understanding of human communication. Some research results are summarized in this document and my future research plan is described.
1827196
Network architecture to support QoS in mobile ad hoc networks [video streaming applications]
We present a quality of service (QoS) architecture for supporting real-time data transmission in mobile ad hoc networks (MANETs). The QoS architecture includes a QoS transport layer, QoS routing, queue management and a priority MAC protocol. Through simulations, we find that the QoS architecture reduces packet delay and greatly improves the quality of real-time video streams in MANETs.
13418028
Discovering matching dependencies
Matching dependencies (MDs) are recently proposed for various data quality applications such as detecting the violation of integrity constraints and duplicate object identification. In this paper, we study the problem of discovering matching dependencies for a given database instance. First, we formally define the measures, support and confidence, for evaluating the utility of MDs in the given database instance. Then, we study the discovery of MDs with certain utility requirements of support and confidence. Exact algorithms are developed, together with pruning strategies to improve the time performance. Finally, our experimental evaluation demonstrates the efficiency of the proposed methods.
16858369
Efficient Processing of Metric Skyline Queries
Skyline query is of great importance in many applications, such as multi-criteria decision making and business planning. In particular, a skyline point is a data object in the database whose attribute vector is not dominated by that of any other objects. Previous methods to retrieve skyline points usually assume static data objects in the database (i.e. their attribute vectors are fixed), whereas several recent work focus on skyline queries with dynamic attributes. In this paper, we propose a novel variant of skyline queries, namely metric skyline, whose dynamic attributes are defined in the metric space (i.e. not limited to the Euclidean space). We illustrate an efficient and effective pruning mechanism to answer metric skyline queries through a metric index. Most importantly, we formalize the query performance of the metric skyline query in terms of the pruning power, by a cost model, in light of which we construct an optimized metric index aiming to maximize the pruning power of metric skyline queries. Extensive experiments have demonstrated the efficiency and effectiveness of our proposed pruning techniques as well as the constructed index in answering metric skyline queries.