Time filter

Source Type

Beijing, China

Zeng Z.,China University of Petroleum - East China | Zhang T.,Wuhan University | Li Q.,Shenzhen University | Wu Z.,NavInfo Co. | And 2 more authors.
International Journal of Geographical Information Science | Year: 2016

Map matching method is a fundamental preprocessing technique for massive probe vehicle data. Various transportation applications need map matching methods to provide highly accurate and stable results. However, most current map matching approaches employ elementary geometric or topological measures, which may not be sufficient to encode the characteristic of realistic driving paths, leading to inefficiency and inaccuracy, especially in complex road networks. To address these issues, this article presents a novel map matching method, based on the measure of curvedness of Global Positioning System (GPS) trajectories. The curvature integral, which measures the curvedness feature of GPS trajectories, is considered to be one of the major matching characteristics that constrain pairwise matching between the two adjacent GPS track points. In this article, we propose the definition of the curvature integral in the context of map matching, and develop a novel accurate map matching algorithm based on the curvedness feature. Using real-world probe vehicles data, we show that the curvedness feature (CURF) constrained map matching method outperforms two classical methods for accuracy and stability under complicated road environments. © 2015 Taylor & Francis. Source

Li Q.,Hubei Engineering University | Li Q.,Hubei University | Zeng Z.,China University of Petroleum - East China | Zhang T.,Hubei Engineering University | And 3 more authors.
International Journal of Applied Earth Observation and Geoinformation | Year: 2011

Optimal paths computed by conventional path-planning algorithms are usually not "optimal" since realistic traffic information and local road network characteristics are not considered. We present a new experiential approach that computes optimal paths based on the experience of taxi drivers by mining a huge number of floating car trajectories. The approach consists of three steps. First, routes are recovered from original taxi trajectories. Second, an experiential road hierarchy is constructed using travel frequency and speed information for road segments. Third, experiential optimal paths are planned based on the experiential road hierarchy. Compared with conventional path-planning methods, the proposed method provides better experiential optimal path identification. Experiments demonstrate that the travel timeis less for these experiential paths than for paths plannedby conventional methods. Results obtained for a case study in the city of Wuhan, China, demonstrate that experiential optimal paths can be flexibly obtained in different time intervals, particularly during peak hours. © 2010 Elsevier B.V. Source

Wang J.,Hong Kong University of Science and Technology | Liu C.,NavInfo Co. | Shen T.,Hong Kong University of Science and Technology | Quan L.,Hong Kong University of Science and Technology
Proceedings - 3rd IAPR Asian Conference on Pattern Recognition, ACPR 2015 | Year: 2015

We propose a novel method for recognizing irregular patterns in facades. An irregular pattern is an incomplete 2D grid, representing the placements of repetitive structural architectural objects (e.g., windows), which is capable of being generalized to a variety of facade structures. To effectively recognize such a pattern, we jointly model objects and object structures in a unified Marked Point Process framework, where the architectural objects are abstracted as sparsely populated geometric entities and the pairwise spatially interactions are modeled as elliptical repulsion fields. To optimize the proposed model, we introduce a structure-driven Monte Carlo Markov Chain (MCMC) sampler, by which the irregular pattern hypotheses are iteratively constructed in a bottom-up manner and verified in a top-down manner. The solution space is explored more efficiently for fast convergence. Extensive experiments have shown the efficiency and accuracy of our method of parsing a large category of facades. © 2015 IEEE. Source

Zhe Z.,China University of Petroleum - East China | Zhang T.,Wuhan University | Zou H.,Shenzhen Urban Planning and Land Resource Research Center Pand | Wu Z.,NavInfo Co.
IEEE Conference on Intelligent Transportation Systems, Proceedings, ITSC | Year: 2015

In this paper, we present a novel speedup technique for Floating Car Data (FCD) map matching which exploits the upper bound of driving distance between two adjacent track points. The traveling speed of floating car can be employed for estimating the upper bound, which can restrict the computational magnitude of all pairs shortest paths to the acceptable extent in the preprocessing stage. The overhead for shortest paths between adjacent track points, which is a major part of online map matching, can be greatly reduced by querying the results from the preprocessing stage. The proposed method can hasten massive FCD map matching to achieve real time high-performance and be easily integrated into on-line map matching methods. © 2015 IEEE. Source

Zhang Y.,NavInfo Co. | Zhang Y.,Satellite Environment Center | Fung T.,Chinese University of Hong Kong
Environment and Planning B: Planning and Design | Year: 2013

On the basis of the principle of sustainable development, land-use planning often requires a compromise between economic development and environmental conservation with social justice advocated. Given that values, perceptions, and ideas vary among stakeholders, land-use planning often involves a variety of conflicts with advocating public participation. In this paper we focus on extending the decision-support capabilities of public participation GIS (PPGIS) to facilitate conflict resolution. In the proposed model, conflicts are designated to be investigated and resolved from two levels, namely the value level and the specifics level. From the value level, a consensus-building process is proposed to help participants promote mutual understanding and achieve group agreement. At the specifics level, participants are asked to search for compromise space through discussions over particular concerns. The ultimate goal of the model is to help participants to work out the most acceptable land-use plan. Moreover, a PPGIS prototype with the conflict resolution model was designed and implemented in the context of Lantau Island, Hong Kong. The study could contribute to PPGIS research and land-use planning by developing the methodology of conflict resolution. The challenges that we encountered and some future directions are also covered in the paper. Source

Discover hidden collaborations