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Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research 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.)

Based on the teaching contents of unmanned aerial vehicle ( UAV) High t control and image processing in unmanned aerial vehicle remote sensing course, the paper designed and built a four rotor UAV teaching experimental platform based on photoelectric image processing. In order to achieve the autonomous Bight control of the quadrotor, an autonomous flight control hardware platform is designed in which a self-assembly aircraft is used as the body frame based on image processing and recognition. The main on-board sensor is attitude sensor MPU6050 and camera OV7725. An ARM microcontroller is used to construct the main control chip, R5F100LEA series chip is used as assistant chip. Based on the nonlinear dynamic model of the quadrotor, a single-loop P1D control algorithm and image processing and recognition are designed, this design realizes the self-assembly aircraft system which can fulfill specific task. Experimental results show that the on-board control system has achieved good flight performance and we finish the following task like following the line, picking and searching specific things with the corporation of two chips. [ABSTRACT FROM AUTHOR]

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine 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 Natural Gas Industry is the property of Natural Gas Industry Journal Agency 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 Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications 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 Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research 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.)

In order to solve the problem of weak covertness, small hiding capacity and poor robustness of Tibetan webpage information hiding (111) technique, a novel 1H scheme with synchronization mechanism for Tibetan web page ( 1HSTW ) is proposed. Firstly, the bit sequence of secret message is disordered by scrambling transformation algorithm. Then the synchronous Baker code is added into this scrambled bit sequence to form a new bit sequence. Lastly, the bit "0" and ' 1' of this new bit sequence is embedded into Tibetan webpage through changing the upper or lower case of tag attribute names in its HTML code. Experimental results show that, compared with other existing III methods, I11STW can increase the information hiding capacity effectively with good covertness and present better robustness under heavy random perturbation. [ABSTRACT FROM AUTHOR]

Objective To investigate the changes in levels of portal venous blood prostacyclin I2 ( PGI2) and thromboxane A2 (TXA2) in patients with colorectal carcinoma and their clinical significance. Methods Sixty patients with colorectal carcinoma were selected in the study，including 22 cases with synchronous liver metastasis ( liver metastasis group )，38 cases without liver metastasis ( non-liver metastasis group )，20 cases in stage II of pTNM staging，32 cases in stage H ，and 8 cases in stage IV. Meanwhile，16 cases of postoperative adhesive intestinal obstruction were considered as controls ( control group ). The levels of PGI2 and TXA2 in the portal venous blood，tumor tissues，and normal colorectal mucosae were detected by radioimmunoassay，respectively ，and then were compared with those of the controls. Results Compared with the normal colorectal mucosae，the level of TXA2 increased，while the level of PGI2 decreased significantly in the colorectal cancer tissues ( both P < 0 .01 ); compared with the control group，the level of PGI2 increased，and the ratio of PGI2/TXA2 and TXA2 decreased significantly in the non-liver metastasis group and liver metastasis group ( all P < 0. 01 ). Compared with the non-liver metastasis group， the level of portal venous blood PGI2 and the ratio of PGI2/TXA2 decreased，TXA2 increased in the liver metastasis group (all P < 0.01). Compared with patients whose tumor maximum diameter ≤3.0 cm，3. 1 cm - 4 . 0 cm，the level of PGI2 and the ratio of PGI2/TXA2 decreased，TXA2 increased in patients with tumor diameter > 4 .0 cm ( all P < 0.05 ). The ratio of PGI2/TXA2 value of portal vein was negatively correlated with the size of the tumor ( r = -0 .770 ). The ratio of PGI2/TXA2 in portal vein blood of patients with colorectal cancer and synchronous liver metastasis was lower than that without metastasis ( P < 0 .01 ). Conclusions The level of TXA2 increases and the ratio of PGI2/TXA2 decreases in the portal vein blood of patients with colorectal cancer. The decreased ratio of PGI2/TXA2 of portal vein blood may be one of the important causes of synchronous liver metastasis of colorectal cancer. [ABSTRACT FROM AUTHOR]

Up to date, simulation of subsonic flows over the high lift device is still a challenge, especially for the cases with higher angles of attack. In order to evaluate the ability of HyperFLOW, an in-house CFD software for subsonic turbulence flow over complex geometries based on structured and unstructured grids, the NASA high lift trap wing model is selected and investigated. Two cases discussed in the NASA high-lift workshop are considered on three types of grids, i.e. two unstructured or mixed grids, and one multi-block structured grid. The simulations on coarse, medium and fine grids for each type are carried out to access the performance of grid convergence. The numerical results are analyzed using Richardson extrapolation method, and compared with the experimental data and the results by other famous CFD codes in the world. The comparison demonstrates that HyperFLOW has a good property of grid convergence on different grids. As the statistical conclusions of the NASA high-lift workshop, the numerical results are acceptable within the linear part of the aerodynamic forces in the regime of lower and medium angles of attack. However, it is still a challenge for the prediction of the cases in higher angles of attack, especially for the cases near stall. [ABSTRACT FROM AUTHOR]