Portfolio optimization is a paramount and important issue in the financial technology area. Constructing a portfolio requires simultaneous considerations of both return and risk, and the proposed system utilizes the trend ratio based on funds standardization, which can effectively evaluate the performance of a portfolio by its returns and risks, while the quantum-inspired tabu search (QTS) algorithm can be used to efficiently build the best portfolio with a stable uptrend. As it is difficult for users to observe a large amount of stock data, this system helps investors to deal with portfolio optimization issues and further provides an information visualization interface to analyze more investment situations. The user interface of the proposed system provides a new service for users to get started quickly in stock selection and clearly analyze the performance of portfolios in the different stock markets. The proposed method can also push notifications automatically when the system detects that the trend of the user’s portfolio is going to slow down, and reminds them to invest in new portfolios with a strong uptrend in a timely manner. The system also designs three games. The first two games make people familiar with stocks. The third game combines social computing with gameplay, which helps to simultaneously find a better portfolio in the highly complex data. In addition, our system provides the functions of general financial applications, such as stock price inquiry, financial news, etc.

When a number of persons, e.g., a family or a group of friends, drive their vehicles for a trip together, they can form a fleet of vehicles and share their network resources during their trip. Let one member want to watch a video from the Internet. He may not have high resolution or video quality due to his limited 3G/3.5G bandwidth to the Internet. The cooperative video streaming scenario allows the requested member to ask other members of the same fleet to download video cooperatively. In other words, other members can help to download parts of the video from the Internet and then forward video data to the requested member hop by hop through the ad-hoc network. This work proposes the k-hop cooperative video streaming protocol using H.264/SVC over the hybrid vehicular networks which consist of 3G/3.5G cellular network and Dedicated Short-Range Communications (DSRC) ad-hoc network. In order to smooth video playback over the DSRC-based ad-hoc network, this work proposes: (1) one streaming task assignment scheme that schedules the streaming task to each member over the dynamic vehicular networks, and (2) packet forwarding strategies that decide the forwarding sequence of the buffered video data to the requested member hop by hop. Finally, we utilize the network simulator version 2 (NS2) to simulate the proposed protocol. Based on the simulation results, the proposed scheme can estimate the assignment interval adaptively and the playback priority first (PPF) strategy has the best performance for the k-hop video forwarding over the hybrid vehicular networks.

With the development of vehicular networks, new types of networking services arise for automotive users. Since vehicles have high mobility, it is difficult to keep stable and reliable network connections between vehicles. With regard to multi-media streaming services, a vehicle may not have good QoS of video streaming using a single 3G/3.5G wireless interface. This paper is motivated to investigate the cooperative streaming sce-nario in a fleet-based vehicular network. When a vehicle requests a video stream encoded in H.264/SVC from the Internet using its 3G/3.5G network, it asks for nearby vehicles belonging to the same fleet to download the requested video data cooperatively through these nearby vehicles' 3G/3.5G network and then forward these downloaded video to the requested vehicle through V2V Dedicated Short-Range Communication (DSRC) networks. Since the topology of a vehicular network may change dynamically, an adaptive video transmission scheme is utilized to control the sending rate of the server to avoid the congestion of vehicular networks and retransmit the lost video to the requester to improve the quality of video before the playback deadline. We utilize EstiNet Network Simulator and Emulator (NCTUns) to simulate the proposed schemes. Based on the simulation results, the proposed priority first retransmission scheduling (PFRS) can have higher PSNR values in the network condition with lower Bit Error Rates (BER) and the dependency cost retransmission scheduling (DCRS) would have higher PSNR values in the network condition with higher BER.

SUMMARY In this paper, a distributed telematics peer‐to‐peer networking system is proposed to provide an efficient and feasible service discovery mechanism for mobile users. When mobile users travel on the road, they may request for some services from service providers to meet their demands. Mobile users in vehicles are assumed to go through a lot of regions, in which each region is associated with a region server. Related information of all service providers in a region is stored in its region server, and each region server is in charge of the service discovery requests from all vehicles located in its region. This paper focuses on the issues of developing a distributed peer‐to‐peer telematics service discovery networking system over the vehicular network environment for mobile users. To provide the communication mechanism for telematics service discovery among region server, mobile users, and service providers, the Telematics Service Markup Language is proposed. According to clients' demands, three types of query scenarios are proposed, which are (1) reference point based query, (2) continual query, and (3) route‐based query. Finally, we present usage examples and system implementation of distributed telematics peer‐to‐peer. Copyright © 2012 John Wiley & Sons, Ltd.

When a passenger in a vehicle wants to watch video during movement, he may request video through cellular network, e.g., 3G or 3.5G network. However, due to the characteristics of vehicular networks, the limited bandwidth of 3G/3.5G network is not enough to support high resolution or high video quality. In order to improve the quality of video playback, this vehicle, which is defined as requester in this paper, may try to ask other members of the same fleet to download video cooperatively. In other words, other members would download parts of requested video through their 3G/3.5G network individually and then forward video data hop by hop to the requester using the DSRC ad-hoc network. In order to smooth the DSRC ad-hoc network, we propose and discuss two k-hop packet forwarding schemes for the aforementioned cooperative video streaming over vehicular networks in this paper. Each intermediary node of the forwarding route must decide how to deliver buffered video data through the limited DSRC network. Finally, the NS2 simulation tool is adopted to evaluate the proposed schemes. Based on the simulation results, the Playback Priority First (PPF) scheme is performed better than the First-In First-Out (FIFO) scheme.

When a vehicle requests a video streaming service from the Internet, it may not have enough bandwidth to receive good video quality. In order to resolve this problem, the vehicle is proposed to ask neighboring vehicles to help the video download process using a short-range wireless technique, i.e. Dedicated Short Range Communications (DSRCs). In this paper, this scenario is called cooperative streaming over vehicular networks. Since the topology of vehicular networks changes over time rapidly, three critical issues in the moving-vehicle-based cooperative streaming are: (i) how to form a cooperative group dynamically, (ii) how to schedule neighboring vehicles to help the video download process and (iii) how to estimate the possible change of network conditions. We propose corresponding control schemes to tackle the aforementioned issues in this paper. From the simulation results, we can find that different scheduling schemes are adaptive to different scenarios, and the proposed dynamic group formation scheme has better performance than that of periodic group formation scheme.

In this paper, we proposed a K-hop bandwidth aggregation scheme for member-based cooperative video streaming over the hybrid vehicular networks consisting of DSRC ad hoc network and 3G/3.5G cellular network. Each member in the same group is known to each other, e.g., they may be a family or a group of friends driving their sedans and they set out from the same position along the same path to the same destination during the journey. When a member in a vehicle wants to watch video during traveling, he will request video through 3G/3.5G network. However, the limited bandwidth of the 3G/3.5G network is not enough to support higher resolution or higher quality of downloading video. In order to enhance the quality of video playback, the member, who is called requester, in one vehicle can ask members, who are called helpers, of the same group in other vehicles to cooperatively download video through their 3G/3.5G networks and then forward their downloaded video to the requester through the DSRC ad hoc network. In order to select suitable members as helpers to download and forward the video and make video streaming more effectively to the requester over the DSRC Ad hoc vehicular network, how to select suitable helpers to forward the downloaded video hop-by-hop back to the requester needs to be resolved. In this paper, we proposed a K-hop bandwidth aggregation scheme to tackle the aforementioned problem. The performance results show that our proposed scheme can get better quality video than cooperative video streaming schemes without the deliberately designed K-hop bandwidth aggregation mechanism.

Due to the advance of wireless and mobile technologies, vehicular networks are widely discussed in recent years. When a vehicle requests a video stream from the Internet using the cellular network, i.e., 3G or 3.5G network, it may not have enough bandwidth to receive good quality of video. In order to resolve this problem, the vehicle can ask neighboring vehicles for the help of downloading the video stream. This scenario is called cooperative streaming in vehicular communications. The vehicle can communicate with neighboring vehicles using a short-range wireless technique, e.g., Dedicated Short Range Communications (DSRC). Since the topology of vehicle networks changes rapidly, two critical issues in the moving vehicle-based cooperative streaming are (1) how to form a cooperative group dynamically and (2) how to schedule neighboring vehicles to help the video downloading process. The simulation results reveal that the improvement of video quality is proportional to (1) high traffic flow, (2) high probability of willingness to share bandwidth and (3) low relative speed.

With the maturation of wireless networks technologies, Telematics service is becoming a new rising and popular network service and application. In this paper, a centralized vehicular Peer-to-Peer Telematics (C-VP2P) service discovery platform is proposed to provide efficient and feasible service discovery. This paper focuses on the issues of developing a Telematics service platform over the vehicular network environment. When a user needs a service on the road, two issues need to be considered: (1) how to have the candidate list of service providers? (2) how to select suitable service providers from the candidate list? In order to tackle these two issues, we propose a C-VP2P-based system service discovery mechanism using the vehicular P2P messaging protocol. In this paper, the vehicular P2P messaging protocol is designed to communicate among Telematics central server, clients and service providers. In addition, a service discovery mechanism in the C-VP2P system is proposed to achieve high precision discovery for service providers. We also exhibit the performance merits of the proposed C-VP2P Telematics service discovery platform in this paper.

In this paper, we propose a combined SVC-MDC (scalable video coding & multiple description coding) video coding scheme using the multi-core parallel programming paradigm for P2P video streaming, which is denoted Co-SVC-MDC. To date, P2P video streaming applications are widely popular and emphasized, e.g., PPstream and PPlive, because of higher transmission speed and data availability. However, in the heterogeneous P2P network environment, users are able to utilize PDA, notebook or desktop computer through distinct network interfaces to get on-demand videos ubiquitously. To provide distinct spatial-resolution/fidelity videos and flexible video transmission (playback) over P2P networks, a brand new coding architecture needs to be devised. In the proposed Co-SVC-MDC coding scheme, distinct MDC descriptions contain distinct portions of raw video frames, and each raw frame can be compressed as base layer and SVC enhancement layers. In our experiments, a real implementation of Co-SVC-MDC is exhibited and corresponding performances, e.g., PSNR and decoding speeds, are compared with original SVC in distinct congestion-level P2P networks.

In order to adapt the quality of videos streamed over a time-varying bandwidth channel, a network-aware bandwidth management and rate control are required. This paper proposes the well-designed bandwidth estimation and active buffer control for streaming H.264 FGS videos over heterogeneous wired/ wireless/3G networks. According to the information of measured packet round-trip-time, loss-rate and delay jitter, an improved Kalman filter is proposed to predict the throughput recursively, and determine the transmission rate in consideration of buffer fullness of a decoder. The optimal parameters of the Kalman filter, e.g., transition matrix and error covariance, can be initialized, converged and adapted to the current network, even when the session handoff occurs. In our real experiments, distinct network traffic models are simulated, and corresponding estimation results w.r.t. network information are also exhibited.