Recent Patents on Computer Science - Volume 7, Issue 2, 2014

Distributed video coding (DVC) is considered to be a potential solution for various applications, e.g. wireless multimedia sensor networks, mobile devices, owing to the feature of easy encoding/complex decoding. However, practical DVC systems still have a rate distortion (RD) performance gap with respect to the traditional video coding standards with complex encoding/easy decoding. Side information, created at the DVC decoder as the temporal prediction for the current Wyner-Ziv (WZ) frame, is of great importance for improving the RD performance of DVC. This paper firstly compares the SI used by DVC and the traditional video coding standards respectively. The comparison reveals that the information and the way to exploit the information used in the SI generation are the most important factors affecting the system's performance. According to the types of information used in SI creation, the related papers and patents are roughly classified into three classes: using the external-info (the previous decoded frames at the decoder), using the extrainfo (the information extracted at the encoder and sent to the decoder), and the main-info (the parity bits of the current WZ frame and the main signal of transmission). The various methods of exploiting the three types of information to generate SI are surveyed and discussed. Finally some future potential developments are concluded.

To improve the transfer efficiency of urban passenger hub, the platforms, stations and transfer routes were expressed as variables based on Graph theory. The calculation methods for passenger transfer time of the routes were developed based on regression model. Conflict level of traffic flow was measured by a weighting model. A bi-level programming model was brought forward, where the upper level was transfer time minimum and the lower level was traffic conflict level minimum. The optimization plan of transfer organization was established based on a compromise model. Taking Chuangchun railway station hub as an example, the required traffic data were collected. The current transfer plan was evaluated and existing problems were found. Then a new transfer plan was proposed based on the optimization model. The linear weighting of transfer time and conflict level was selected as the evaluation index, and the two plans were compared. The results show that the new plan can decrease total conflict by 89.4% and transfer time by 51.5%.

The path following control strategies for a six-wheel lunar rover under loose soil terrains were proposed after building the rover sideslip model, as well as the sideslip and slippage model of each wheel. The design of controller was done using the prior layered hierarchical architecture. The path following control level only considered the sideslip of rover. The inner control level took the sideslip and slip of each wheel as corrections to the inverse kinematics of the rover, which is helpful to prevent the rover from losing traction performance caused by excessive wheel slippage. Several path following control simulations were conducted under different kinds of soft terrain conditions. Simulation patent results show that the proposed path following control method can guarantee the traction performance and provide favorable control effects.

Water hazard is one of the most dangerous obstacles for unmanned vehicle to travel in off-road environment. The vision information for water hazard body includes relatively high brightness, low saturation and smooth texture. In this paper, static image and sequence image are captured by CCD. Color and texture information extracted from image pixels would be utilized to form a feature matrix to train the SVM classifier. While, with the assistance of RBF kernel function, low-dimensional sample space is projected to high-dimensional space. Based on large amount of experiments, RBF kernel function parameters are optimized by using grid method. The optimized RBF kernel function parameters are proved satisfactory when detecting in the static water image. Notice that there is certain relationship between target position and its scale for the adjacent frame. SURF feature detection and matching method can be used to match feature point between adjacent frames in image sequences. The searching window size and position in new frame could be updated in time, which allows to detect water hazard in a relatively small region. Water obstacle tracking experiment with patents proved the satisfactory performance of the SURF method in this paper.

Today more and more people have concerned about how to reduce the energy consumption of vehicles on road in urban city. This paper uses the petrol car as research object, researching the energy saving of vehicles in conditions of real urban transportation. The best travel route of the energy saving is found by comparing different travel routes, and it is finally proved that there exists a travel route that may not be the shortest one but is the one which has the least fuel consumption. Firstly, two experimental lines are selected which have the same origin and destination but have different travel routes. By using the geographic information of Google Earth, we collected the information of latitude and longitude based on the manually labeled, and combined MATLAB to generate the road map of city with intersection identifies. We chose two trial routes, and used separately fuel consumption instrument to collect fuel consumption data of vehicles by doing vehicle test on two different paths of the trial route. Secondly, test database is built and relative data is manipulated. According to the changes of city's traffic flow in one day, test time is divided into four different periods: morning peak period, morning off-peak period, evening off-peak period and evening peak period, the data of every period is divided into leaving trip and returning trip, and database is built by MATLAB. The vehicle fuel consumption is contrastively analyzed from different angles, such as period and direction. According to the experiment data, the average speed and percentage of idle time were calculated, and fuel consumption model per 100 kilometers was established based on these two parameters. Results of calculation with model are in agreement with the fuel consumption of test to a certain extent, therefore, it is also proved with patents that the fuel consumption model has high reliability.