China Transport Telecommunications and Information Center

Beijing, China

China Transport Telecommunications and Information Center

Beijing, China

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Shen G.,China Transport Telecommunications and Information Center
2016 3rd International Conference on Systems and Informatics, ICSAI 2016 | Year: 2016

The damage of road surface reduces its service life. In order to improve road maintenance and management efficiency, detection and recognition of pavement are studied based on video images in this paper. Firstly, we collect a large number of road surface images of 3 different conditions including transverse crack, longitudinal crack and turtle crack separately to construct road surface conditions library. Secondly, deal the road damaged image with gray, gray transform and image smoothing. Then, use mathematical morphology method to deal with crack image and projection to identify crack category. Finally, develop the pavement crack recognition software based on Matlab. Selecting the pavement samples for experiment, the results show that this identification algorithm can accurately identify the category of crack. © 2016 IEEE.


Xie C.,China Transport Telecommunications and Information Center
International Conference on Geoinformatics | Year: 2016

Selecting the official land cover data from the government-led Geographical Conditions Survey of China and utilizing the method of global and local spatial autocorrelation based on grid processing, the authors analyzed Yingkou City's characteristics of land cover spatial autocorrelation pattern. The study suggested following conclusions: 1) The Global Moran's I index of all types of land cover in Yingkou City were greater than 0.35, whose confidence level was higher than 95%. The results showed that there are strong spatial autocorrelations among different types of land cover in this area. 2) The Local Moran's I Index showed that there are significant differences in various types of land cover's coverages and ranges of the spatial aggregation or anomaly. 3) Using the cross-variable correlation analysis, the authors discussed the relationships and distribution patterns of different land cover types. This research was helpful to reveal the correlation between the spatial autocorrelation of land cover and types of land cover. The study above was also suitable for large-scale regional application, and the results were significant important for the geographical conditions monitoring. © 2015 IEEE.


Wu D.,Wuhan University of Technology | Lu H.,Wuhan University of Technology | Chen W.,China Transport Telecommunications and Information Center | Yang X.,Hubei Station of Surveying Products Quality Supervision and Checkout
ICTIS 2015 - 3rd International Conference on Transportation Information and Safety, Proceedings | Year: 2015

BeiDou pseudolites (BPLs), ground-based BeiDou-like signals transmitters, are capable of augmenting positioning accuracy, reliability, availability of the BeiDou satellite navigation system. However, implementation of the BPLs lead to another problem-the 'near far problem', where the satellite signals are blocked by the signals from a BPL. One of the promising solutions is to pulse the BPL signals to reduce the interference. Because the existing pulsing schemes, i.e., the RTCM SC-104 and the RTCA SC-159 are designed for the GPS signals, they cannot be simply adopted in the BeiDou system due to the different signal structures. Therefore, a dedicated BPLs signals pulsing scheme is proposed in this paper. Two critical parameters-duty cycle and pulse pattern which characterize a pulsing scheme are analyzed and determined in the proposed scheme. Besides, the transmission power requirement is explained in details. The simulation proves that this scheme meets all identified requirements, making it a viable solution to mitigate the near-far problem. © 2015 IEEE.


Xie C.,China Transport Telecommunications and Information Center | Liu P.,CAS Institute of Remote Sensing | Xu L.,Lanzhou University
International Geoscience and Remote Sensing Symposium (IGARSS) | Year: 2015

Using AMSR-E soil moisture and MODIS data, the authors developed a new downscaling algorithm for large-scale soil moisture data according to the spectrum downscaling algorithm by improving the model fitting equation and the evapotranspiration mode. The comparison with in situ data from Asia-Australia Monsoon Project of Coordinated Energy and water-cycle Observation Project (CEOP) in Mongolia showed that the downscaled soil moisture data and its changing trends was in good agreement with measured data. Hence the authors confirmed the downscaling method introduced in the paper was of high accuracy and credibility. © 2015 IEEE.


Wu D.,Wuhan University of Technology | Chen W.,Wuhan University of Technology | Li J.,China Transport Telecommunications and Information Center | Lu H.,China Transport Telecommunications and Information Center | Ji J.,Wuhan University of Technology
Lecture Notes in Electrical Engineering | Year: 2016

With the purpose of overall performance enhancement, binary offset carrier (BOC) modulation is proposed to replace the existing quadrature phase shift keying (QPSK) signal in the BeiDou system. Multipath performance comparisons between these two signals have been performed using the error envelops providing ideal signal scenarios. However, this method gives only qualitative statements without considering realistic signal characteristics. In order to produce a quantitative assessment of the multipath performance in different environments, power delay profile (PDP) models are built based on field measurement data to simulate the real-world multipath channels. It is proven by the simulation results that the BeiDou BOC(14,2) signal outperforms QPSK(2) signal by 60% overall error reduction in four typical environments: open, rural, suburban, and urban. The simulation results also testify that double-delat correlator (DDC) has more influence on the BOC(14,2) in comparison to narrower correlator. © Springer India 2016.


Su D.,Wuhan University of Technology | Chen W.,Wuhan University of Technology | Zhou Z.,China Transport Telecommunications and Information Center | Lu H.,China Transport Telecommunications and Information Center
Proceedings - 2015 International Conference on Industrial Informatics - Computing Technology, Intelligent Technology, Industrial Information Integration, ICIICII 2015 | Year: 2015

In this paper, an integrated positioning algorithm based on BD/2 and GPS is proposed. The design principle and mathematical derivation of the integrated algorithm are developed from the principle of the traditional GNSS system. On the basis of the least-squares algorithm, the weighted least-squares method and Kalman filter algorithm for the integrated navigation system were used. The optimized weighted least squares method has advantages in the respect of simplification and error scatter gather degree. Kalman filter algorithm is validated by the simulation that the proposed algorithm is able to provide a smooth integrated navigation service with higher accuracy than the stand-alone GNSS system. © 2015 IEEE.


Wang L.,University of Waterloo | Li J.,University of Waterloo | Duguay C.,University of Waterloo | Li D.,China Transport Telecommunications and Information Center
International Geoscience and Remote Sensing Symposium (IGARSS) | Year: 2015

Snow is a very important component of the climate system. It can influence the energy budget of the atmosphere and hydrological system significantly. The main goal of this paper is to use remote sensing and geographical information system techniques to analyze the spatial and temporal variations in regional scale and to find the relations between meteorological parameters and the snow albedo for the future modeling in snow albedo study. The results revealed spatial and temporal variation throughout different months during the winter season. In addition, the Pearson correlation coefficient analysis showed partial correlation between snow albedo and meteorological variables, which can be used to model snow albedo in some hydrological studies. © 2015 IEEE.


Wang A.,North China University of Technology | Liu P.,CAS Institute of Remote Sensing | Xie C.,China Transport Telecommunications and Information Center
International Conference on Geoinformatics | Year: 2016

Synthetic Aperture Radar (SAR) images are widely used in land use classification. However, the influences of buildings may cause classification errors when SAR images are applied in urban areas. Aiming at the property of low Signal to Noise Ratio (SNR) of SAR images and the complexity of building textures, we obtained the initial segmentation using the Maximum likelihood (ML) algorithm based on the multi-scale Markov Random Field (MRF) model and involved the Gabor similarity between pixels based on the traditional MRF potential function, and employed the Iterative Conditional Model algorithm to implement the segmentation. And we classified the segmentation image by using the K-means classification algorithm. The experimental results on several real SAR images showed that the proposed approach performs better than traditional methods in the segmentation accuracy, and building boundaries were clearly obtained by the proposed approach. © 2016 IEEE.


Li N.,CHANGJIANG PILOT Center | Li H.,Hubei Inland Shipping Technology Key Laboratory | Yang X.,China Transport Telecommunications and Information Center | Wen Y.,China Transport Telecommunications and Information Center
ICTIS 2015 - 3rd International Conference on Transportation Information and Safety, Proceedings | Year: 2015

According to the features of the high temperature's impacts on inland shipping, the impacts were divided into light, moderate and severe level. Based on the series data of temperature time in seventeen stations which near the coastal area of Middle Yangtze River during the period between 1965 and 2008, the characteristics of climate variations influenced by the high temperature are analyzed and discussed by the linear trend estimation and wavelet method. The results was that the influences in light and moderate levels were increased, while it was reduced slightly in moderate level (the absolute value were less than 2.5d/10a), which indicated that the ones in the former two levels are more frequent and fluctuating. Besides, there were distinct periodic oscillations around 5-15a and 15-30a periods for multi-Time structures in temperature variations. In addition, severe heat wave and the high temperature existed in all seventeen stations, which could have important effects on the goods transportation and the crew on the ship. Therefore the protective measures should be taken to ensure the navigation safety. © 2015 IEEE.


Bingqi Z.,China Transport Telecommunications and Information Center | Rong L.,China Transport Telecommunications and Information Center
2015 International Association of Institutes of Navigation World Congress, IAIN 2015 - Proceedings | Year: 2015

Transportation is the largest application field of satellite navigation at present, which has the characteristics of large scale, multi-mode, wide range, high demand and so on. Currently, Ministry of Transport of the People's Republic of China is promoting the construction of Four Traffic (Comprehensive Traffic, Intelligent Traffic, Green Traffic and Safe Traffic) and higher demand for the precision, continuity and reliability of satellite navigation service is proposed. The construction of satellite navigation augmentation system has become the objective demand for the in-depth application of satellite navigation in transportation. Satellite navigation augmentation system can be divided into temporary augmentation system and permanent augmentation system based on the analysis in this paper. Permanent augmentation system includes dedicated system, professional public service system, general public service system and commercial service system. Permanent augmentation system has experienced the preliminary development stage and the independent development stage oriented to various professional applications. At present, permanent augmentation system has entered the stage of resource sharing and integration development which has the main characteristics of basic integration, products segmentation, diversity service and application popularization. The construction of China satellite navigation augmentation system is under the second development stage and the augmentation system should be constructed according to the characteristics of the third stage. The construction of China Beidou ground-based augmentation system was started in the middle of 2014 which will have the effect of basic fusion. Based on this, Ministry of Transport of the People's Republic of China is discussing the construction of China transportation BeiDou augmentation application system. This paper analyzed the inland, coast, road transport, road infrastructure and public transport demand for high precision navigation position service, and then proposed the general concept of the construction of China transportation on satellite navigation augmentation system and experimental verification is carried out focus on transportation satellite navigation augmentation service application. © 2015 IEEE.

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