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| 1 | Sedimentation processes and sedimentary characteristics of tidal bores along the north bank of the Qiantang Estuary显示文摘A tidal bore is a unique Earth surface process, characterized by its highly destructive energy, predictable periodicities and magni-tudes, and the production of characteristic sedimentary features. Tidal bores and associated rapid flood flows are highly turbulent flows of the upper-flow regime with a velocity over several meters per second. Reynolds (Re) and Froude (Fr) numbers, respectively, are larger than 104 and 1.0, making them significantly different from regular tidal flows but analogous to turbidity currents. Until now, understanding of tidal-bore depositional processes and products has been limited because of the difficulty and hazards involved with gauging tidal bores directly. The Qiantang bore is known as the largest breaking bore in the world. Field surveys were carried out in May 2010, along the north bank of the Qiantang Estuary to observe the occurrence of peak bores, including regular observations of current, water level and turbidity at the main channel. Several short cores were sampled on the intertidal flats to study the characteristic sedimentary features of tidal bores. Hydrodynamic and sedimentological studies show that the processes of sediment resuspension, transport and deposition are controlled primarily by the tidal bores, and the subsequent abruptly accelerated and decelerated flood flows, which only account for one tenth of each semidiurnal tidal cycle in the estuary. Tidal-bore deposits are generally poorly sorted because of rapid sedimentation after highly mixed suspension by intense turbulence. This behavior is characteristic of the absence of tractive-current depositional components in a C-M diagram. It also goes along with well-developed massive bedding, graded bedding, basal erosion structures, convolute bedding and dewatering structures. Together, these sedimentary features can constitute fingerprinting of turbidites, widely distributed in the deep-water environment. However, a tidal bore is triggered by intensely deformed tidal waves propagating into a shallow-water environment, which returns to regular tidal flows rapidly after the passage of the bore head. The tidal-bore deposits are usually bounded by the intertidal-flat deposits with typical tidal beddings at the top and on both flanks. The difference between tidal-bore deposits (TBD) and tidal sandy/muddy deposits (TSD/TMD) is evident not only in sedimentary structures, but also in the grain-size composition. They can be clearly distinguished in grain-size bivariate plots, typically the plot of mean grain size vs. standard deviation (or sorting). Some trend variations generally exist in mean grain size with TBD>TSD>TMD, sorting with TMD>TBD>TSD (larger value indicating poorer sorting), and both skewness and kurtosis with TSD>TBD>TMD. These findings will undoubtedly shed new light on our understanding of tidal-bore sedimentology, ancient tidal-bore sedimentary facies and environments, and related oil-and-gas field prospecting. | FAN DaiDux CAI GuoFu SHANG Shuai WU YiJing ZHANG YanWei GAO Lei | 2012 | Chinese Science Bulletin2012，57，13： | 8 |
| 2 | Development of an Intelligent Vehicle Experiment System显示文摘Existing vehicle experiment systems tend to focus on the research of vehicle dynamics by conducting performance tests on every system or some parts of the vehicle so as to improve the entire performance of the vehicle.Virtual technology is widely utilized in various vehicle test-beds.These test-beds are mainly used to simulate the driving training,conduct the research on drivers' behaviors,or give virtual demonstrations of the transportation environment.However,the study on the active safety of the running vehicle in the virtual environment is still insufficient.A virtual scene including roads and vehicles is developed by using the software Creator and Vega,and radars and cameras are also simulated in the scene.Based on dSPACE's rapid prototyping simulation and its single board DS1103,a simulation model including vehicle control signals is set up in MATLAB/Simulink,the model is then built into C code,and the system defined file(SDF) is downloaded to the DS1103 board through the experiment debug software ControlDesk and is kept running.Programming is made by mixing Visual C++ 6.0,MATLAB API and Vega API.Control signals are read out by invoking library function MLIB/MTRACE of dSPACE.All the input,output,and system state values are acquired by arithmetic and are dynamically associated with the running status of the virtual vehicle.An intelligent vehicle experiment system is thus developed by virtue of program and integration.The system has not only the demonstration function,such as general driving,cruise control,active avoiding collision,but also the function of virtual experiment.Parameters of the system can be set according to needs,and the virtual test results can be analyzed and studied and used for the comparison with the existing models.The system reflects the running of the intelligent vehicle in the virtual traffic environment,at the same time,the system is a new attempt performed on the intelligent vehicle travel research and provides also a new research method for the development of intelligent vehicles. | YANG Xinhong GAO Feng LIU Guoliang WANG Guofu XU Guoyan | 2010 | Chinese Journal of Mechanical Engineering2010，23，6： | 5 |
| 3 | Dynamic Modeling and Analysis of 9-DOF Omnidirectional Legged Vehicle显示文摘The omnidirectional legged vehicle with steering-rails has a specific mechanism feature, and it can be controlled flexibly and accurately in omnidirectional motion. Currently there lacks further research in this area. In this paper, the mechanical characteristics of independent walking control and steering control and its kinematics principle are introduced, and a vehicle has a composite motion mode of parallel link mechanism and steering mechanism is presented. The motion direction control of the proposed vehicle is only dependant on its steering rails, so its motion is simple and effective to control. When the relative motion between the walking and steering is controlled cooperatively, the vehicle can walk perfectly. By controlling the steering rails, the vehicle can walk along arbitrary trajectory on the ground. To achieve a good result of motion control, an equivalent manipulator model needs to be built. In terms of the mechanism feature and the kinematic principle, the simplified manipulator model consists of a rail in stance phase, a rail in swing phase, and an equivalent leg. Considering the ground surface slope during walking, a parameter of inclination angle is added. Based on such a RPP manipulator model, the equations of motion are derived by means of Lagrangian dynamic approach. To verify the dynamic equations, the motion of the manipulator model is simulated based on linear and nonlinear motion planning. With the same model and motion parameters, the dynamic equations can be solved by Matlab and the calculation data can be gained. Compared with the simulation data, the result confirms the manipulator dynamic equations are correct. As a result of such special characteristics of the legged mechanism with steering rails, it has a potential broad application prospects. The derivation of dynamics equation could benefit the motion control of the mechanism. | GAO Feng WANG Guofu CUI Ying YANG Xinhong | 2011 | Chinese Journal of Mechanical Engineering2011，24，4： | 3 |
| 4 | Organic matter enrichment in the first member of the Xiagou formation of the lower Cretaceous in the Jiuquan Basin, China显示文摘The sources and enrichment of organic matter in a sediment core in the first member of the Xiagou Formation(K_1g^1) from the Chang 2-2 borehole of the Jiuquan Basin,NW China,have been examined using Rock-Eval,maceral,carbon isotopes and biomarker data.This data indicates that highly variable organic matter sources and preservation conditions in response to climate change.TOC content,HI,and δ^(13)C value were strongly correlated with the abundance of gammacerane,woody organic matter content,steranes/hopanes ratio,and C_(29) sterane content.This correlation demonstrates the importance that the control of the salinity of the depositional environment and organic matter sources can have upon the enrichment,type,and carbon isotopic composition of organic matter.In the Jiuquan Basin's relatively high temperature and arid climate,high salinity lakes with high primary productivity of algae,planktons,and bacteria,and good organic matter preservation conditions(anoxic bottom water) resulted in the enrichment of isotopically-light algae-bacterial organic matter.In the Jiuquan Basin's regions with a relatively low temperature and wet climate,fresh lakes with low primary productivity of algae,planktons,and bacteria received significant terrigenous high plants input,resulting in the deposition of a low abundance of isotopically heavier terrestrial organic matter. | Lixin Pei Gang Gao Wenzhe Gang Zhilong Huang Guofu Ma Zhiming Yang Jianjun Chen | 2016 | Acta Geochimica2016，35，1： | 2 |
| 5 | Influence of longitudinal-torsional ultrasonic-assisted vibration on micro-hole drilling Ti-6Al-4V显示文摘As Ti-6 Al-4 V is a typical hard to machine material,especially in micro drilling aviation parts,chip breaking difficulty is of increasing interest to explore its further development.In this study,Longitudinal-Torsional Ultrasonic Assisted Drilling(LTUAD)was employed to machine Ti-6 Al-4 V,and its feasibility was evaluated by comparing with Conventional Drilling(CD).By combining periodical characteristics and vibration models(the separated or the unseparated ultrasonic elliptical vibration),the influence of ultrasonic frequency on the intersection characteristics of trajectories were analyzed.And the intersection characteristics were divided into four categories:even periodicity,odd periodicity,non-odd and even periodicity and composite periodicity,indicating different capability for chip breaking.By applying the longitudinal-torsional compound vibration horn,the micro-hole drilling experiment was carried out on machining center.The chip morphology,the thrust force,and the burr height were discussed.Experimental results showed that the morphology of chips presented as smaller and more fragmentary ones in LTUAD compared with continuous helical conical ones and fold-shaped ones in CD.Compared with CD,the average values of the thrust force in LTUAD reduced by 1.98%to 24.9%.According to the burr around the hole exit in both LTUAD and CD,the height of the latter was greatly affected by the drilling parameters.And the burr around the exit of the hole were distributed rather evenly with smaller extension in LTUAD.Consequently,the LTUAD employed in micro-hole drilling was effective. | Guofu GAO Ziwen XIA Zhaojie YUAN Daohui XIANG Bo ZHAO | 2021 | Chinese Journal of Aeronautics2021，34，9： | 2 |
| 6 | Research on surfaceroughness and micro-topography of Nano-ZrO2 plate intwo-dimensional ultrasonic grinding显示文摘 | Bo Zhao Mingli Zhao Guofu Gao | 2008 | Advanced Mate-rials Research2008，5354，： | 1 |
| 7 | Surface characteristics in the ultrasonic ductile honing of ZrO2 ceramics using coarse grits 显示文摘 | Bo Zhan Chuanshao Liu Guofu Gao | 2002 | Journal of Materials Processing Technology2002，，123： | 1 |
| 8 | Ferroelectricity in dopant-free HfO_(2) thin films prepared by pulsed laser deposition显示文摘As a high-k material,hafnium oxide(HfO_(2))has been used in gate dielectrics for decades.Since the discovery of polar phase in Si-doped HfO_(2) films,chemical doping has been widely demonstrated as an effective approach to stabilize the ferroelectric phase in HfO_(2) based thin films.However,the extra capping layer deposition,post-growth annealing and wake-up effect are usually required to arouse the ferroelectricity in HfO_(2) based thin films,resulting in the increase of complexity for sample synthesis and the impediment of device application.In this study,the ferroelectricity is observed in non-capped dopant-free HfO_(2) thin films prepared by pulsed laser deposition(PLD)without post-growth annealing.By adjusting the deposited temperature,oxygen pressure and thickness,the maximum polarization up to 14.7 m C/cm^(2) was obtained in 7.4 nm-thick film.The fraction of orthorhombic phase,concentrations of defects and size effects are considered as possible mechanisms for the influences of ferroelectric prop-erties.This study indicates that PLD is an effective technique to fabricate high-quality ferroelectric HfO_(2) thin films in the absence of chemical doping,capping layer deposition and post-growth annealing,which may boost the process of nonvolatile memory device application. | Yongjian Luo Zhenxun Tang Xiaozhe Yin Chao Chen Zhen Fan Minghui Qin Min Zeng Guofu Zhou Xingsen Gao Xubing Lu Jiyan Dai Deyang Chen Jun-Ming Liu | 2022 | Journal of Materiomics2022，8，2： | 1 |
| 9 | Experimental research on temperature field in ultrasonic assisted grinding engineering ceramics显示文摘 | Gao Guofu Liu Chuanshao Zhao Bo | 2008 | Key Engineering Materials2008，364，： | 1 |
| 10 | Research on micro characteristics of surface and subsurface layer in two-dimensional ultrasonic grinding nano-composite ceramics 显示文摘 | Zhao Bo Gao Guofu | 2008 | Key Engineering Materials2008，，： | 1 |
| 11 | Research on surface roughness and micro-topography of nano-ZrO2 plate in two-dimension ultrasonic grinding 显示文摘 | Zhao Bo Zhao Mingli Gao Guofu | 2008 | Advanced Materials Research2008，53，： | 1 |
| 12 | Research on surface roughness and micro-topography of nano-ZrO2 pPlate in two-dimensional ultrasonic grinding显示文摘 | ZHAO Bo ZHAO Mingli GAO Guofu | | 0，，： | 1 |
| 13 | Surface characteristics in the ultrasonic ductile honing of ZrO2 ceramics using coarse grits 显示文摘 | Zhao Bo Liu Chuanshao Gao Guofu | 2002 | Journal of Materials Processing Technology2002，123，： | 1 |
| 14 | Surface char- acteristics in the ultrasonic ductile honing of ZrO2 ce- ramics using coarse grits显示文摘 | Zhao Bo Liu Chuanshao Gao Guofu | 2002 | Journal of Materials Process- ing Technology2002，123，1： | 1 |
| 15 | Research on micro characteristics of surface and subsurface layer in two-dimensional ultrasonic grinding nano - composite ceramics显示文摘 | Zhao Bo Gao Guofu | 2008 | Key Engineering Materials2008，，： | 1 |
| 16 | Surface characteristics in the ultrasonic ductile honing of ZrO2 ceramics using coarse grits显示文摘 | Zhao Bo Liu Chuanshao Gao Guofu | 2002 | Journal of Materials Processing Technology2002，123，1： | 1 |
| 17 | Surface characteristics in the ultrasonic ductile honing of ZrO2 ceramics using coarse grits 显示文摘 | Zhao Bo Liu Chuanshao Gao Guofu | 2002 | Journal of Materials Processing Technology2002，，123： | 1 |
| 18 | Surface Characteristics in the Ultrasonic Ductile Honing of ZrO2 Ceramics Using Coarse Grits显示文摘 | Zhao Bo Liu Chuanshao Gao Guofu | 2002 | Journal of Material Processing Technology2002，123，1： | 1 |
| 19 | Surface characteristics in the ultrasonic ductile honing of ZrO2 ceramics using coarse grits显示文摘 | Zhao Bo Liu Chuanshao Gao Guofu eatl | 2002 | Journal of Materials Processing Technology2002，123，： | 1 |
| 20 | Surface characteris-tics in the ultrasonic ductile honing of ZrO2 ceramics using coarse grits显示文摘 | Liu Chuanshao Gao Guofu | 2002 | Journal of Materials Processing Technology2002，，123： | 1 |
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