Building an Intelligent Mobile Advertising System

The fast deployment of wireless networks and mobile technologies and the significant increase in the number of mobile device users have created a very strong demand for new innovative mobile commerce applications and services. Since mobile advertising is one of the important subjects in mobile commerce, studying and developing mobile advertising solutions becomes a hot research and business topic. This paper first discusses the basic concepts of mobile advertising. Then, it reports a mobile advertising system (known as SmartMobile-AD), including its supporting business process, functions, system architecture, and built-in technical solutions. The system supports the wireless advertising workflow for wireless service companies and publishers (or portals) to manage and deliver multimedia mobile ads to mobile users over the wireless Internet. The paper provides insights and design solutions on mobile advertisement targeting, delivery, tracking, and performance measurement. Furthermore, the paper presents application examples of the system.

Network Layer Mobility Management Schemes for IP-Based Mobile Networks

Mobility is a natural phenomenon in cellular networks. The worldwide popularity of mobile communications and Internet has necessitated the merger of the two fast growing technologies to get their fullest advantages. The Internet protocol (IP) was designed for static hosts only. Therefore, in order to add mobility in Internet, the Internet protocol needs to be redefined. This paper is intended to present an overview of various mobility management schemes, available in literature, for IP-based mobile networks.

On Uplink Channel Estimation in WiMAX Systems

In this paper, channel estimation algorithms are proposed and compared for uplink WiMAX systems, which are OFDMA based. These algorithms are investigated based on a dynamic resource allocation scheme, and it is shown that each of them is suitable to specific system scenarios. For example, for a system with a bandwidth of 10MHz operating in the low frequency region (2-11GHz), a two-dimensional averaging algorithm outperforms other algorithms, such as a bilinear interpolation algorithm, because the correlations between the pilots and signals are sufficiently high in both the frequency and the time dimensions.

Options for WiMAX Uplink Media Streaming

IEEE 802.16e (mobile WiMAX) uplink behavior is a relatively neglected area of investigation, but emerging interactive media services have highlighted the need for closer investigation of uplink issues. In this simulation study of uplink queue management, the authors found that media streaming by TCP-Friendly Rate Control (TFRC) has advantages. However, temporal behavior of the queuing disciplines exhibits oscillations in buffer occupancy with build-up of delay during video streaming. This paper suggests a possible remedy lies in the choice of the more complex H.264/AVC Main profile, but this will impact upon mobile devices. It was also found that WiMAX video delivery is sensitive to choice of transmission frame size.

Improving Throughput of Starved TCP Flow by Sidestepping Bottleneck Nodes Using Concurrent Transmission

The TCP congestion control mechanism along with unfairness problem poses poor performance when IEEE 802.11 MAC protocol is used in multi-hop ad hoc networks because the traditional TCP has poor interaction with the IEEE 802.11 MAC protocol. Because of the greedy nature of TCP, starvation problem of TCP flows with longer paths is severe. In this paper, we first illustrate that the fairness, congestion control and medium contention are closely coupled issues and the spatial reuse of the channel can improve the performance of wireless ad hoc network. By using concurrent transmission protocol at the MAC layer, like CTMAC, in multi-hop networks we can achieve simultaneous transmissions within the interference regions. Further, we illustrate with extensive simulations in ns-2 that by scheduling multiple concurrent transmissions along the path links, the starvation problem due to greedy nature of TCP can be eliminated and ensuing higher flow throughput and lower end-to-end delay.

A Probabilistic Routing Protocol in VANET

The key attribute that distinguishes Vehicular Ad hoc Networks (VANET) from Mobile Ad hoc Networks (MANET) is scale. While MANET networks involve up to one hundred nodes and are short lived, being deployed in support of special-purpose operations, VANET networks involve millions of vehicles on thousands of kilometers of highways and city streets. Being mission-driven, MANET mobility is inherently limited by the application at hand. In most MANET applications, mobility occurs at low speed. By contrast, VANET networks involve vehicles that move at high speed, often well beyond what is reasonable or legally stipulated. Given the scale of its mobility and number of actors involved, the topology of VANET is changing constantly and, as a result, both individual links and routing paths are inherently unstable. Motivated by this latter truism, the authors propose a probability model for link duration based on realistic vehicular dynamics and radio propagation assumptions. The paper illustrates how the proposed model can be incorporated in a routing protocol, which results in paths that are easier to construct and maintain. Extensive simulation results confirm that this probabilistic routing protocol results in more easily maintainable paths.

Pertinent Prosodic Features for Speaker Identification by Voice

Most existing systems of speaker recognition use “state of the art” acoustic features. However, many times one can only recognize a speaker by his or her prosodic features, especially by the accent. For this reason, the authors investigate some pertinent prosodic features that can be associated with other classic acoustic features, in order to improve the recognition accuracy. The authors have developed a new prosodic model using a modified LVQ (Learning Vector Quantization) algorithm, which is called MLVQ (Modified LVQ). This model is composed of three reduced prosodic features: the mean of the pitch, original duration, and low-frequency energy. Since these features are heterogeneous, a new optimized metric has been proposed that is called Optimized Distance for Heterogeneous Features (ODHEF). Tests of speaker identification are done on Arabic corpus because the NIST evaluations showed that speaker verification scores depend on the spoken language and that some of the worst scores were got for the Arabic language. Experimental results show good performances of the new prosodic approach.

Automatic Speaker Localization and Tracking

This paper presents a system of speaker localization for a purpose of speaker tracking by camera. The authors use the information given by the two microphones, placed in opposition, to determine the position of the active speaker in trying to supervise the audio-visual recording. To achieve the speaker localization task, the authors have proposed and employed two methods, which are called respectively: the filtered correlation method and the energy differential method. The principle of the first method is based on the calculation of the correlation between the two signals collected by the two microphones and a special filtering. The second is based on the computation of the logarithmic energy differential between these two signals. However, when different methods are used simultaneously to make a decision, it is often interesting to use a fusion technique combining those estimations or decisions in order to enhance the system performances. For that purpose, this paper proposes two fusion techniques operating at the decision level which are used to fuse the two estimations into one that should be more precise.

A Proposed Intelligent Denoising Technique for Spatial Video Denoising for Real-Time Applications

With the widespread use of videos in many fields of our lives, it becomes very important to develop new techniques for video denoising. Spatial video denoising using wavelet transform has been the focus of the current research, as it requires less computation and more suitable for real-time applications. Two specific techniques for spatial video denoising using wavelet transform are considered in this work: 2D Discrete Wavelet Transform (2D DWT) and 2D Dual Tree Complex Wavelet Transform (2D DTCWT). We performed an analytical analysis to investigate the performance of each of these techniques. From this analysis, we found out that each of these techniques has its advantages and disadvantages. The first technique gives less quality at high levels of noise but consumes less time, whereas the second gives high quality video while consuming a large amount of time. In this work, we introduce an intelligent denoising system that makes a tradeoff between the quality of the denoised video and the time required for denoising. The system first estimates the noise level in the video frame then chooses the proper denoising technique to apply on the frame. The simulation results show that the proposed system is more suitable for real-time applications where time is critical, while still giving high quality videos at low to moderate levels of noise.

Memorizing Algorithm

The rapid development of location-based services, which make use of the location information of the user, presents both opportunities and challenges. Users can benefit from these services; however, they must often disclose their location information, which may lead to privacy problems. In this regard, the authors propose a solution with a memorizing algorithm, using trusted middleware that organizes space in an adaptive grid where it cloaks the user’s location information in an anonymization area before sending it to the service providers. This newly introduced memorizing algorithm calculates on the spatial grid to decrease the overlapped areas as much as possible, which helps conceal users’ locations. This solution protects the user’s privacy while using the service, but also against data mining techniques with respect to their history location data. Experimental results with a user activities map establishes this theoretical analyses as well as the practical value of the proposed solution.