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Dry deposition of PM_(10) over the Yellow Sea during Asian dust events from 2001 to 2007

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Journal of Environmental Sciences 2014年第1期26卷 54-64页

作者： Han Yan Xiaohuan Liu Jianhua qi Huiwang gao Key Laboratory of Marine Environment and Ecology Ocean University of China Ministry of Education of China National Marine Environmental Forecasting Center

Dry deposition velocities and fluxes of PM10 during Asian dust events over the Yellow Sea from 2001 to 2007 were investigated using observation data in qingdao, China and Jeju, Korea. The dry deposition velocities of PM 10 during dust events over the Yellow Sea ranged from 0.19 to 8.17 cm/sec, with an average of 3.38 cm/sec. Dry deposition fluxes of PM10 during dust events over the Yellow Sea were in the range of 68.5-2647.1 mg/（***）, with an average of 545.4 mg/（***）, which is 2-10 times higher than those reported by other studies for both dust and non-dust periods. It was estimated that 2.6× 10^11-48.7 × 10^11 g dust particles deposit to the Yellow Sea during dust events through dry deposition every year. Compared with the results in previous studies, it was found that the dry deposition of PM10 over the Yellow Sea during dust events in the years with high frequency of dust could account for a large or overwhelming fraction of the annual total dry deposition. Backward air mass trajectory analysis showed that dust events influenced Jeju mainly originated from the desert regions located in Mongolia and Inner Mongolia, China. There were 119 backward trajectories influenced both qingdao and Jeju during 15 dust events from 2001 to 2007, accounting for 61.3% of the total trajectories of 194, indicating that qingdao and Jeju were usually on the same pathway of dust transport downwind from source areas.

关键词： Asian dust the Yellow Sea dry deposition fluxes backward trajectory analysis

Danshensu Ameliorates Cardiac Ischaemia Reperfusion Injury through Activating Sirt1/Fox01/Rab7 Signal Pathway

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Chinese Journal of Integrative Medicine 2020年第4期26卷 283-291页

作者： SUN Da-wei gao qing qi Xin Department of Neurology Tianjin Academy of Traditional Chinese Medicine Affiliated HospitalTianjin(300120)China School of Integrative Medicine Tianjin University of Traditional Chinese MedicineTianjin(301617)China Department of Cardiology Tianjin Union Medical CenterTianjin(300121)China

Objective:To explore the specific molecular mechanisms of Danshensu(DSS)in the treatment of ischemia reperfusion injury(IRI).Methods:IRI model was established with isolated rat hearts by performing global ischaemia for 30 min,and then followed by 60 min ***,H9C2 cells were subjected to 4-h hypoxia followed by 3-h *** 10|i mol/L DSS were added in the reperfusion/reoxygenation step to intervene *** function,structural change and apoptosis were respectively tested by Langendorff System,hematoxylin and eosin(HE)and terminal-deoxynucleotidyl transferase mediated nick endabeling(TUNEL)*** lactate dehydrogenase(LDH),cardiac troponin T(cTnT),reactive oxygen species(ROS),superoxide dismutase(SOD)and glutathione peroxidase(GSH-PX)were detected by enzyme-linked immunosorbent assay(ELISA).Sirt1/FoxO1/Rab7 Signal Pathway was monitored at both protein and mRNA ***:The results showed that IRI not only greatly attenuated cardiac function(LVDP and±dp/dtmax,P<0.01,P<0.05)and increased the level of the marker enzymes(cTnT,LDH,P<0.01)from the coronary effluents,but also markedly induced changes in the structure of cardiomyocytes and contributed to apoptosis,which were mediated by boosted en doge nous ***,after treatment with DSS all above indexes were improved,which was related to activating Sirt1/FoxO1/Rab7 signal pathway accompanied with the enhancement of antioxidant defense system,such as SOD and ***:DSS is able to protect hearts from IRI,which may be attributable to inhibiting excessive ROS through Sirt1/FoxO1/Rab7 signaling.

关键词： Chinese medicine Danshensu ischemia reperfusion injury Sirt1/FoxO1/Rab7 signal pathway reactive oxygen species apoptosis

Application of Artificial Neural Network to Predicting Hardenability of Gear Steel

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Journal of Iron and Steel Research International 2006年第6期13卷 71-73页

作者： gao Xiu-hua qi Ke-min DENG Tian-yong qiU chun-lin ZHOU Ping DU Xian-bin State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China Technical Center Laiwu Iron and Steel Co Ltd Laiwu 271104 Shandong China

The prediction of the hardenability and chemical composition of gear steel was studied using artificial neural networks. A software was used to quantitatively forecast the hardenability by its chemical composition or the chemical composition by its hardenability. The prediction result is more precise than that obtained from the traditional method based on the simple mathematical regression model.

关键词： artificial neural network (ANN) gear steel hardenability 20CrMnTiH

Human-Tracking Strategies for a Six-legged Rescue Robot Based on Distance and View

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Chinese Journal of Mechanical Engineering 2016年第2期29卷 219-230页

作者： PAN Yang gao Feng qi Chenkun CHAI Xun State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University

Human tracking is an important issue for intelligent robotic control and can be used in many scenarios, such as robotic services and human-robot cooperation. Most of current human-tracking methods are targeted for mobile/tracked robots, but few of them can be used for legged robots. Two novel human-tracking strategies, view priority strategy and distance priority strategy, are proposed specially for legged robots, which enable them to track humans in various complex terrains. View priority strategy focuses on keeping humans in its view angle arrange with priority, while its counterpart, distance priority strategy, focuses on keeping human at a reasonable distance with priority. To evaluate these strategies, two indexes（average and minimum tracking capability） are defined. With the help of these indexes, the view priority strategy shows advantages compared with distance priority strategy. The optimization is done in terms of these indexes, which let the robot has maximum tracking capability. The simulation results show that the robot can track humans with different curves like square, circular, sine and screw paths. Two novel control strategies are proposed which specially concerning legged robot characteristics to solve human tracking problems more efficiently in rescue circumstances.

关键词： human-tracking legged robot intelligent control algorithm

NO Decomposition on Rh Supported CNTs

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Chinese Chemical Letters 2001年第1期12卷 83-86页

作者： Shui Hua TANG Bao chun LIU qi LIANG Li Zhen gao Liang Fu ZHANG Zuo Long YU Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041

The decomposition of NO has been studied in a steady flow reactor on fresh carbon nanotubes (CNTs), purified CNTs, Rh/p-CNTs and Rh/gamma -Al2O3 between 573 K and 973 K. NO decomposition at 573 K was initially complete over a reduced surface. The amount of NO absorption increased at temperature below 773 K. 100% NO conversion and more than 100% N-2 activity was achieved at 973 K for 150 min on p-CNTs and f-CNTs.

关键词： NO decomposition NO absorption carbon nanotubes rhodium

Gait Planning for a Quadruped Robot with One Faulty Actuator

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 11-19页

作者： CHEN Xianbao gao Feng qi Chenkun TIAN Xinghua State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University

Fault tolerance is essential for quadruped robots when they work in remote areas or hazardous environments. Many fault-tolerant gaits planning method proposed in the past decade constrained more degrees of freedom（DOFs） of a robot than necessary. Thus a novel method to realize the fault-tolerant walking is proposed. The mobility of the robot is analyzed first by using the screw theory. The result shows that the translation of the center of body（CoB） can be kept with one faulty actuator if the rotations of the body are controlled. Thus the DOFs of the robot body are divided into two parts： the translation of the CoB and the rotation of the body. The kinematic model of the whole robot is built, the algorithm is developed to actively control the body orientations at the velocity level so that the planned CoB trajectory can be realized in spite of the constraint of the faulty actuator. This gait has a similar generation sequence with the normal gait and can be applied to the robot at any position. Simulations and experiments of the fault-tolerant gait with one faulty actuator are carried out. The CoB errors and the body rotation angles are measured. Comparing to the traditional fault-tolerant gait they can be reduced by at least 50%. A fault-tolerant gait planning algorithm is presented, which not only realizes the walking of a quadruped robot with a faulty actuator, but also efficiently improves the walking performances by taking full advantage of the remaining operational actuators according to the results of the simulations and experiments.

关键词： quadruped robot fault-tolerant gait mobility kinematic redundancy

Existence and exponential stability of almost-periodic solutions for MAM neural network with distributed delays on time scales

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Applied Mathematics(A Journal of Chinese Universities) 2021年第1期36卷 70-82页

作者： gao Jin WANG qi-ru LIN Yuan School of Computer Sciences Shenzhen Institute of Information TechnologyShenzhen 518172China School of Mathematics Sun Yat-sen UniversityGuangzhou 510275China Department of Public Courses Shenzhen Institute of Information TechnologyShenzhen 518172China

This paper is concerned with multidirectional associative memory neural network with distributed delays on almost-periodic time *** sufficient conditions on the existence,uniqueness and the global exponential stability of almost-periodic solutions are *** example is presented to illustrate the feasibility and effectiveness of the obtained results.

关键词： multidirectional associative memory neural networks time scales almost-periodic solutions,exponential stability.

Sensitivity Analysis of a Bioinspired Refractive Index Based Gas Sensor

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Journal of Bionic Engineering 2011年第3期8卷 323-334页

作者： Yang gao qi Xia Guanglan Liao Tielin Shi Wuhan National Laboratory for Optoelectronic Wuhan 430074 P. R. Chinao State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074 P. R. China

It was found out that the change of refractive index of ambient gas can lead to obvious change of the color of Morpho butterfly＇s wing. Such phenomenon has been employed as a sensing principle for detecting gas. In the present study, Rigorous Coupled-Wave Analysis （RCWA） was described briefly, and the partial derivative of optical reflection efficiency with respect to the refractive index of ambient gas, i.e., sensitivity of the sensor, was derived based on RCWA. A bioinspired grating model was constructed by mimicking the nanostructure on the ground scale of Morpho didius butterfly＇s wing. The analytical sensitivity was verified and the effect of the grating shape on the reflection spectra and its sensitivity were discussed. The results show that by tuning shape parameters of the grating, we can obtain desired reflection spectra and sensitivity, which can be applied to the design of the bioinspired refractive index based gas sensor.

关键词： bioinspired gas sensor sensitivity diffraction gratings refractive index subwavelength structures

A Simplified Control Method to Achieve Stable and Robust Quadrupedal Quasi-passive Walking with Compliant Legs

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Journal of Bionic Engineering 2016年第4期13卷 585-599页

作者： qiao Sun Feng gao Chenkun qi Xianbao Chen State Key Laboratory of Mechanical System and Vibration Shanghai Jiaotong University Shanghai 200240 China

The principle of passive dynamic walking has drawn lots of attentions in the field of robotics for it provides a possibility to realize natural walking. However, stabilizing the quadrupedal passive walking remains challenging. In this paper, a novel control method is proposed to stabilize the quadrupedal quasi-passive walking. Inspired by biological concepts, this method treats the foreleg pair and hindleg pair as two bipedal walkers, and a virtual model controller is designed to maintain the quasi-passive walking of each bipedal walker independently. This control method was then verified by a planar quadrupedal model with compliant legs, which successfully achieved stable periodical walking gaits. It was found that although being con- trolled independently, the movement of fore and hind leg pairs still formed a time-invariant phase shift, showing remarkable resemblance to that of a walking horse. We fiarther analyzed the influences of varying factors on the gait characteristics and stability. These analyses show the control method is robust since it can stabilize the gaits within a wide range of leg compliance parameters and resist considerably large disturbances. In addition, the optimal ranges of the leg compliance parameters for the largest stability margin were also found in this study.

关键词： quadrupedal walking quasi-passive walking leg compliance independent control