Flight and Hover Control System Design for a Mini-quadrotor Based on Multi-sensors

Zhongli Ma,Huixin Li,Yanming Gu,Zuoyong Li,Qianqian Li 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.2

Mini-quadrotor is difficult to control in the air due to its small size and light weight. This paper presentsthe flight and hover control system for a mini-quadrotor, including design and simulation of calculations and controllers. Firstly, the attitude and position of the mini-quadrotor are obtained by distributed multi-sensors. Since attitudecalculation of aircraft needs a number of combined rotations and vectors transformed by rotation, quaternionsare applied to express the attitude model. About error compensation of gyroscope and accelerometer, IMU_Updataalgorithm of Mahony filter are applied and improved to realize data fusion [1]. In order to realize accurate hoveringat certain position, UWB (UltraWideband) are applied to gain positional information of mini-quadrotor and correctthe antenna delay caused sensor error by base station positioning. The discrete Kalman filter of original data is usedto achieve the optimized estimation of the airborne position. Px4flow optical flow sensor is able to gets velocityinformation and avoid the noise problem, which is caused by differential of position data. Then, the mathematicalmodel of a mini-quadrotor’s flight and hover control system can be established. Herein, integral items are solved bythe integral separation and integral limiting to mitigate the serious overshoot and oscillation of the system caused bythe cascade PID. Finally, the simulation of the attitude controller and position controller are applied with the MATLABSimulink library. The simulation result shows that the designed attitude controller and position controller canenable the mini-quadrotor to fly smoothly, move in all directions and hover.

A Highly Secure Identity-Based Authenticated Key-Exchange Protocol for Satellite Communication

Zhong Yantao,Ma Jianfeng 한국통신학회 2010 Journal of communications and networks Vol.12 No.6

In recent years, significant improvements have beenmade to the techniques used for analyzing satellite communication and attacking satellite systems. In 2003, a research team at Los Alamos National Laboratory, USA, demonstrated the ease with which civilian global positioning system (GPS) spoofing attacks can be implemented. They fed fake signals to the GPS receiver so that it operates as though it were located at a position different from its actual location. Moreover, Galileo in-orbit validation element A and Compass-M1 civilian codes in all available frequency bands were decoded in 2007 and 2009. These events indicate that cryptography should be used in addition to the coding technique for secure and authenticated satellite communication. In this study, we address this issue by using an authenticated key-exchange protocol to build a secure and authenticated communication channel for satellite communication. Our protocol uses identity-based cryptography. We also prove the security of our protocol in the extended Canetti-Krawczyk model, which is the strongest security model for authenticated key-exchange protocols, under the randomoracle assumption and computational Diffie-Hellman assumption. In addition,our protocol helps achieve high efficiency in both communication and computation and thus improve security in satellite communication.

C1420T Polymorphism of Cytosolic Serine Hydroxymethyltransferase and Risk of Cancer: a Meta-analysis

Zhong, Shan-Liang,Zhang, Jun,Hu, Qing,Chen, Wei-Xian,Ma, Teng-Fei,Zhao, Jian-Hua Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.5

A series of studies have explored the role of cytosolic serine hydroxymethyltransferase (SHMT1) C1420T polymorphism in cancer risk, but their results were conflicting rather than conclusive. To derive a more precise estimation of the association between C1420T and cancer risk, the present meta-analysis of 28 available studies with 15,121 cases and 18,023 controls was conducted. The results revealed that there was no significant association between the polymorphism and cancer risk overall. In stratified analysis by cancer type (breast cancer, gastrointestinal cancer, leukemia, lymphoma, and others), the results showed that 1420T allele was associated with decreased risk in leukemia (CT vs. CC: OR= 0.825, 95% CI =0.704-0.966; and CT+TT vs. CC: OR= 0.838, 95% CI = 0.722-0.973), but the same results were not present for other cancer types. When subgroup analysis was performed by source of control (population-based [PB] and hospital-based [HB]), a borderline inverse association was observed for the HB subgroup (CT vs. CC: OR= 0.917, 95% CI = 0.857-0.982) but not for the PB subgroup. Stratifying by geographic area (America, Asia and Europe), significant inverse association was only found in Asia subgroup (CT vs. CC: OR= 0.674, 95% CI = 0.522-0.870). In summary, the findings suggest that SHMT1 C1420T polymorphism is not associated with overall cancer development, but might decrease cancer susceptibility of Asians as well as reduce leukemia risk. Large well-designed epidemiological studies will be necessary to validate the risk identified in the current meta-analysis.

Enhanced electrical conductivity of nanocomposites containing hybrid fillers of carbon nanotubes and carbon black.

Ma, Peng-Cheng,Liu, Ming-Yang,Zhang, Hao,Wang, Sheng-Qi,Wang, Rui,Wang, Kai,Wong, Yiu-Kei,Tang, Ben-Zhong,Hong, Soon-Hyung,Paik, Kyung-Wook,Kim, Jang-Kyo American Chemical Society 2009 ACS APPLIED MATERIALS & INTERFACES Vol.1 No.5

<P>Nanocomposites reinforced with hybrid fillers of carbon nanotubes (CNTs) and carbon black (CB) are developed, aiming at enhancing the electrical conductivity of composites with balanced mechanical properties while lowering the cost of the final product. Epoxy-based nanocomposites were prepared with varying combinations of CNTs and CB as conducting fillers, and their electrical and mechanical properties were evaluated. It was shown that the addition of CNTs in CB composites enhanced the electrical conductivity of composites: a low percolation threshold was achieved with 0.2 wt % CNTs and 0.2 wt % CB particles. The CB particles also enhanced the ductility and fracture toughness of nanocomposites, confirming the synergistic effect of CB as a multifunctional filler. The novelty of this work lies in the synergy arising from the combination of two conducting fillers with unique geometric shapes and aspect ratios as well as different dispersion characteristics, which have not been specifically considered previously.</P>

Tetrandrine Exerts a Radiosensitization Effect on Human Glioma through Inhibiting Proliferation by Attenuating ERK Phosphorylation

Ma, Ji-wei,Zhang, Yong,Ye, Ji-cheng,Li, Ru,Wen, Yu-Lin,Huang, Jian-xian,Zhong, Xue-yun The Korean Society of Applied Pharmacology 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.2

Tetrandrine (Tet), a bisbenzylisoquinoline alkaloid, has been reported to have a radiosensitization effect on tumors. However, its effects on human glioma and the specific molecular mechanisms of these effects remain unknown. In this study, we demonstrated that Tet has a radiosensitization effect on human glioma cells. It has been hypothesized that Tet has a radiosensitization effect on glioma cells by affecting the glioma cell cycle and DNA repair mechanism and that ERK mediates these activities. Therefore, we conducted detailed analyses of the effects of Tet on the cell cycle by performing flow cytometric analysis and on DNA repair by detecting the expression of phosphorylated H2AX by immunofluorescence. We used western blot analysis to investigate the role of ERK in the effect of Tet on the cell cycle and DNA repair. The results revealed that Tet exerts its radiosensitization effect on glioma cells by inhibiting proliferation and decreasing the expression of phosphorylated ERK and its downstream proteins. In summary, our data indicate that ERK is involved in Tet-induced radiosensitization of glioma cells via inhibition of glioma cell proliferation or of the cell cycle at G0/G1 phase.

Correcting Environmental Market Failures through Environmental Fiscal Reforms in China

Zhong, Ma,Jian, Wu Korean Resource Economics Association 2007 자원·환경경제연구 Vol.16 No.3

By reviewing the current application of Environmental Fiscal Instruments in China, existing policy gaps and weakness, and the feasibility of using EFIs in China, this paper pointed out that the Chinese government faces an historic opportunity for promoting the development of a comprehensive environmental fiscal system. It is proposed that as far as possible the real economic and social costs of pollution and environmental degradation should be reflected in the prices charged for the use of environmental and natural resources. Chinese government should systematize existing environmental fiscal funds and policies, gradually setting up a framework for integrating environmental fiscal instruments into the public financial system.

Correcting Environmental Market Failures through Environmental Fiscal Reforms in China

Ma Zhong,Wu Jian 한국환경경제학회 2007 자원·환경경제연구 Vol.16 No.3

By reviewing the current application of Environmental Fiscal Instruments in China, existing policy gaps and weakness, and the feasibility of using EFIs in China, this paper pointed out that the Chinese government faces an historic opportunity for promoting the development of a comprehensive environmental fiscal system. It is proposed that as far as possible the real economic and social costs of pollution and environmental degradation should be reflected in the prices charged for the use of environmental and natural resources. Chinese government should systematize existing environmental fiscal funds and policies, gradually setting up a framework for integrating environmental fiscal instruments into the public financial system.

Energy Efficiency, Emission Reduction and Low Carbon Development in the Context of China`s Rapid Economic Growth

MA Zhong(馬中) 한국환경정책학회 2010 한국환경정책학회 학술대회논문집 Vol.2010 No.11

Control Over the Branched Structures of Platinum Nanocrystals for Electrocatalytic Applications

Ma, Liang,Wang, Chengming,Gong, Ming,Liao, Lingwen,Long, Ran,Wang, Jinguo,Wu, Di,Zhong, Wei,Kim, Moon J.,Chen, Yanxia,Xie, Yi,Xiong, Yujie American Chemical Society 2012 ACS NANO Vol.6 No.11

<P>Structural control of branched nanocrystals allows tuning two parameters that are critical to their catalytic activitythe surface-to-volume ratio, and the number of atomic steps, ledges, and kinks on surface. In this work, we have developed a simple synthetic system that allows tailoring the numbers of branches in Pt nanocrystals by tuning the concentration of additional HCl. In the synthesis, HCl plays triple functions in tuning branched structures <I>via</I> oxidative etching: (i) the crystallinity of seeds and nanocrystals; (ii) the number of {111} or {100} faces provided for growth sites; (iii) the supply kinetics of freshly formed Pt atoms in solution. As a result, tunable Pt branched structurestripods, tetrapods, hexapods, and octopods with identical chemical environmentcan be rationally synthesized in a single system by simply altering the etching strength. The controllability in branched structures enables to reveal that their electrocatalytic performance can be optimized by constructing complex structures. Among various branched structures, Pt octopods exhibit particularly high activity in formic acid oxidation as compared with their counterparts and commercial Pt/C catalysts. It is anticipated that this work will open a door to design more complex nanostructures and to achieve specific functions for various applications.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2012/ancac3.2012.6.issue-11/nn304237u/production/images/medium/nn-2012-04237u_0010.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn304237u'>ACS Electronic Supporting Info</A></P>

Preparation, Structural Investigation and Thermal Decomposition Behavior of Two High-Nitrogen Energetic Materials: ZTO·2H₂O and ZTO(phen)·H₂O

Ma, Cong,Huang, Jie,Zhong, Yi Tang,Xu, Kang Zhen,Song, Ji Rong,Zhang, Zhao Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.7

Two new high-nitrogen energetic compounds $ZTO{\cdot}2H_2O$ and $ZTO(phen){\cdot}H_2O$ have been synthesized (where ZTO = 4,4-azo-1,2,4-triazol-5-one and phen = 1,10-phenanthroline). The crystal structure, elemental analysis and IR spectroscopy are presented. Compound 1 $ZTO{\cdot}2H_2O$ crystallizes in the orthorhombic crystal system with space group Pnna and compound 2 $ZTO(phen){\cdot}H_2O$ in the triclinic crystal system with space group P-1. In $ZTO(phen){\cdot}H_2O$, there is intermolecular hydrogen bonds between the -NH group of ZTO molecule (as donor) and N atom of phen molecule (as acceptor). Thermal decomposition process is studied by applying the differential scanning calorimetry (DSC) and thermo thermogravimetric differential analysis (TG-DTG). The DSC curve shows that there is one exothermic peak in $ZTO{\cdot}2H_2O$ and $ZTO(phen){\cdot}H_2O$, respectively. The critical temperature of thermal explosion ($T_b$) for $ZTO{\cdot}2H_2O$ and $ZTO(phen){\cdot}H_2O$ is $282.21^{\circ}C$ and $195.94^{\circ}C$, respectively.