Xiping Hu

Vita: A Crowdsensing-Oriented Mobile Cyber-Physical System

As a prominent subcategory of cyber-physical systems, mobile cyber-physical systems could take advantage of widely used mobile devices, such as smartphones, as a convenient and economical platform that facilitates sophisticated and ubiquitous mobile sensing applications between humans and the surrounding physical world. This paper presents Vita, a novel mobile cyber-physical system for crowdsensing applications, which enables mobile users to perform mobile crowdsensing tasks in an efficient manner through mobile devices. Vita provides a flexible and universal architecture across mobile devices and cloud computing platforms by integrating the service-oriented architecture with resource optimization mechanism for crowdsensing, with extensive supports to application developers and end users. The customized platform of Vita enables intelligent deployments of tasks between humans in the physical world, and dynamic collaborations of services between mobile devices and cloud computing platform during run-time of mobile devices with service failure handling support. Our practical experiments show that Vita performs its tasks efficiently with a low computation and communication overhead on mobile devices, and eases the development of multiple mobile crowdsensing applications and services. In addition, we present a mobile crowdsensing application, Smart City, developed on Vita to demonstrate the functionalities and practical usage of Vita.

A Survey on Mobile Social Networks: Applications, Platforms, System Architectures, and Future Research Directions

Mobile social networks (MSNs) have become increasingly popular in supporting many novel applications since emerging in the recent years. Their applications and services are of great interest to service providers, application developers, and users. This paper distinguishes MSNs from conventional social networks and provides a comprehensive survey of MSNs with regard to platforms, solutions, and designs of the overall system architecture. We review the popular MSN platforms and experimental solutions for existing MSN applications and services and present the dominant mobile operating systems on which MSNs are implemented. We then analyze and propose the overall architectural designs of conventional and future MSN systems. In particular, we present the architectural designs from two perspectives: from the client side to the server side, and from the wireless data transmission level to the terminal utilization level. We further introduce and compare the unique features, services, and key technologies of two generations of architectural designs of MSN systems. Then, we classify the existing MSN applications and propose one special form of MSN, i.e., vehicular social network, and demonstrate its unique features and challenges compared with common MSNs. Finally, we summarize the major challenges for on-going MSN research and outline possible future research directions.

Multidimensional context-aware social network architecture for mobile crowdsensing

This article proposes a multidimensional context-aware social network architecture, which aims to provide a mobile ecosystem to enable context awareness in the development and utilization of mobile crowdsensing applications. This mobile ecosystem is constructed to provide context awareness capabilities for different roles (i.e., users or developers) in the system and facilitate interactions between them. This system can ease the development of context-aware mobile applications, and enable context-aware mobile crowdsensing considering environmental, personal, and social information. We present a flow of context-aware solutions designed on this system, and highlight the orchestrations and advantages of different context-aware schemes in the system for different types of users (requesters and participants) in mobile crowdsensing. We demonstrate the feasibility of the proposed mobile ecosystem by presenting a novel context-aware mobile crowdsensing application called Smart City, and evaluate the system performance based on this application.

Vehicular Social Networks: Enabling Smart Mobility

Vehicular transportation is an essential part of modern cities. However, the ever increasing number of road accidents, traffic congestion, and other such issues become obstacles for the realization of smart cities. As the integration of the Internet of Vehicles and social networks, vehicular social networks (VSNs) are promising to solve the above-mentioned problems by enabling smart mobility in modern cities, which are likely to pave the way for sustainable development by promoting transportation efficiency. In this article, the definition of and a brief introduction to VSNs are presented first. Existing supporting communication technologies are then summarized. Furthermore, we introduce an application scenario on trajectory data-analysis-based traffic anomaly detection for VSNs. Finally, several research challenges and open issues are highlighted and discussed.

Lightweight Management of Resource-Constrained Sensor Devices in Internet of Things

It is predicted that billions of intelligent devices and networks, such as wireless sensor networks (WSNs), will not be isolated but connected and integrated with computer networks in future Internet of Things (IoT). In order to well maintain those sensor devices, it is often necessary to evolve devices to function correctly by allowing device management (DM) entities to remotely monitor and control devices without consuming significant resources. In this paper, we propose a lightweight RESTful Web service (WS) approach to enable device management of wireless sensor devices. Specifically, motivated by the recent development of IPv6-based open standards for accessing wireless resource-constrained networks, we consider to implement IPv6 over low-power wireless personal area network (6LoWPAN)/routing protocol for low power and lossy network (RPL)/constrained application protocol (CoAP) protocols on sensor devices and propose a CoAP-based DM solution to allow easy access and management of IPv6 sensor devices. By developing a prototype cloud system, we successfully demonstrate the proposed solution in efficient and effective management of wireless sensor devices.

A Review of Key Issues That Concern the Feasibility of Mobile Cloud Computing

Recently, the arising of cloud computing (CC) concept and explosive growth of mobile applications induce a novel technology, i.e., mobile cloud computing (MCC). By integrating CC into mobile environment, MCC alleviates limitations of mobile devices and proliferates a variety of new fascinating mobile services. The key to enable MCC is to equip mobile users with the data processing and storage abilities in the clouds via wireless networks. In this paper, aiming at facilitating the research of MCC and inducing more research topics regarding MCC, we offer a review of the key issues that concern the feasibility of MCC and identify the corresponding novel techniques to mitigate these key issues. Moreover, we propose a potential framework to enhance the robustness of MCC incorporating these novel techniques.

A Dynamic Graph-Based Scheduling and Interference Coordination Approach in Heterogeneous Cellular Networks

To meet the demand of increasing mobile data traffic and provide better user experience, heterogeneous cellular networks (HCNs) have become a promising solution to improve both the system capacity and coverage. However, due to dense self-deployment of small cells in a limited area, serious interference from nearby base stations may occur, which results in severe performance degradation. To mitigate downlink interference and utilize spectrum resources more efficiently, we present a novel graph-based resource allocation and interference management approach in this paper. First, we divide small cells into cell clusters, considering their neighborhood relationships in the scenario. Then, we develop another graph clustering scheme to group user equipment (UE) in each cell cluster into UE clusters with minimum intracluster interference. Finally, we utilize a proportional fairness scheduling scheme to assign subchannels to each UE cluster and allocate power using water-filling method. To show the efficacy and effectiveness of our proposed approach, we propose a dual-based approach to search for optimal solutions as the baseline for comparisons. Furthermore, we compare the graph-based approach with the state of the art and a distributed approach without interference coordination. The simulation results show that our graph-based approach reaches more than 90% of the optimal performance and achieves a significant improvement in spectral efficiency compared with the state of the art and the distributed approach both under cochannel and orthogonal deployments. Moreover, the proposed graph-based approach has low computation complexity, making it feasible for real-time implementation.

A semantics-based multi-agent framework for vehicular social network development

This paper proposes a semantic-based multi-agent framework to support development of vehicular social network applications. In the programming model of the framework, software platforms of vehicular social network systems can be developed by the collaboration of mobile agents and service (or resident) agents, where resident agents provide application services on devices and mobile agents provide communication services on behalf of owner applications. On top of the device infrastructure, the architecture of the proposed framework consists of three layers: framework service layer, software agent layer and application layer, to fully support dynamic and collaborative tasks of vehicular social networks. The multi-layer architecture design of the framework fully supports self-adaptive applications in vehicular social network environments, and is readily extensible to support new features. Developers can easily and effectively develop diverse applications for the vehicular social networks.

VSSA: a service-oriented vehicular social-networking platform for transportation efficiency

This paper proposes a novel service-oriented vehicular social networking platform called VSSA for transportation efficiency. VSSA consists of two layers: service layer and application layer. The service layer is implemented based on the service-oriented architecture (SOA) to ease application developments. By extending and composing the web services in this layer, application developers can efficiently and flexibly develop different new functions or applications for transportation scenarios. The application layer is oriented to vehicular users and it integrates with functions of mobile social networks. With dynamic and automatic service collaboration support, it enables people to easily collaborate and help each other through their mobile devices in transportation situations. Moreover, VSSA provides a context-awareness mechanism to support automatically and intelligently predicting the potential incoming traffic congestions.

A Service-Oriented Mobile Social Networking Platform for Disaster Situations

This paper proposes a novel service-oriented mobile social networking platform called MS2A for disaster situations. MS2A consists of two layers: service layer and application layer. The service layer is implemented based on the service-oriented architecture (SOA) to ease application developments. By extending and composing the web services at this layer, application developers can efficiently and flexibly develop different new functions or applications for mobile disaster rescue and recovery applications. The application layer is oriented to mobile users and it integrates with functions of mobile social networks. With dynamic and automatic service collaboration support, it enables people to easily collaborate and help each other through their mobile devices in disaster situations. The results of our experiments and demonstration examples given in the paper show the feasibility and desired functionality of MS2A for relieving disaster situations with mobile devices.