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Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Advances in Earth Science (1001-8166) is the property of Advances in Earth Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the problem of single structure style and less system variable for traditional chaotic system, this paper proposed a chaotic circuit, which had more complex dynamic behaviors, high er sensitivity to variable and stronger anti-interference. With the change of circuit parameters, this pa per discussed the different dynamic behaviors of the system in detail based on the adaptive stability criterion and chaos motion theory. In addition, it constructed the corresponding circuit and observed the system dynamics phenomena by oscilloscope. The dynamics phenomena were in accordance with the simulation results of MATLAB, which further proved the feasibility and flexibility of the circuit. On this basis, it put forward and studied the multi-stage combination synchronization based on this system. By constructing different controllers, this paper realized the multi-stage combination synchronization among the eight systems. The simulation results show th at the synchronization scheme has a good effect on convergence speed and precision. [ABSTRACT FROM AUTHOR]

To improve the accuracy of unmanned helicopter, geometry calibration is compulsory. Direct geo-reference experiment is first carried out to verify system's accuracy without any calibration; and then the free network bundle adjustment experiment is undertaken to verify the positioning accuracy of the system without ground control points; finally, a self calibration bundle adjustment is undertaken to calibrate and compensate the camera distortion, interior elements changes, IMU alignment angle. Experimental results show that the unmanned helicopter has high positioning accuracy. The accuracy of direct geo-reference can meet the requirements of emergency mapping, and can be aided by a few ground control points, the positioning accuracy is much better than that of 1:500 mapping requirements, which can be used for conventional surveying and mapping production. After system error compensation, the direct geo-reference accuracy has improved significantly:the planar accuracy has improved by 46.37% and the height accuracy has improved by 62.49%. The flight test of Songshan calibration field shows that the method of calibration and compensation is correct and effective, and the unmanned helicopter has a good prospect for surveying and mapping applications. [ABSTRACT FROM AUTHOR]

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The realization and maintenance of the China geodetic coordinate system 2000 (CGCS2000) depends on GPS technologies, and therefore is a national security risk. BDS began offering services to customers in the Asia-Pacific region in December 2012. It provides a good opportunity to realize and maintain the national terrestrial reference frame (TRF) using BDS system. We focus on how to use BDS observations of BDS/GPS stations with dual-mode receivers to realize the National TRF, aligned to the international terrestrial reference frame (ITRF). Results show that the precision of the horizontal velocity derived from BDS data are comparable to those derived from GPS data at about 2-3 mm/a, using more than two years of observation data. The RMS of the station coordinate residuals, with the linear velocity removed, are better than 0.8 cm and 1.7 cm for the horizontals and verticals, respectively. The current precision of BDS data can allow observation of seasonal displacements in the verticals. System errors related to the longitude and latitude are found in the coordinate differences between BDS and GPS data based on PPP mode. Thus, the current BDS system can be used to realize and maintain the national terrestrial reference frame at cm level. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of Beijing Institute of Technology is the property of Beijing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Considering the wide-range and nonlinear characteristics of strata movement and the demand between large range and high precision in the physical simulation of water-preserved mining, a method for improving displacement measurement precision in physical modeling has been proved by experiments. The results show that the measurement accuracy is improved as the number of reference points and displacements increase. The increase of the number of reference points could reduce the system error which fluctuates in a range depending on the number of reference points and the fluctuation ascribes to the plus or minus of error. The mean error starts to reduce and diminish significantly when the number of reference points is 15 and 25 respectively. Therefore, at least 25 reference points are required to ensure the required precision. The method suggests a way for measuring strata movement in mining physical models. [ABSTRACT FROM AUTHOR]

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)