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Investigation of fine and complex vortex circulation structures

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Science china Earth Sciences 2010年第10期53卷 1552-1558页

作者： LUO ZheXian1,MA GeLan1 & PING Fan2 1 Remote Sensing College,Nanjing university of information Science and Technology,Nanjing 210044,china 2 Laboratory of Cloud-Precipitation physics and Severe Storms(LACS),institute of Atmospheric physics,Chinese Academy of Sciences,Beijing 100029,china 1. Remote Sensing College Nanjing University of Information Science and Technology Nanjing 210044 China2. Laboratory of Cloud-Precipitation Physics and Severe Storms (LACS) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The formation and evolution of fine and complicated vortex circulation structures were investigated using a two-dimensional quasi-geostrophic barotropic model *** find that the highly localized asymmetric and complex configuration of energy transfer flux between large-and small-scale components is caused by the nonlinear interaction between a large-scale vortex with an initial axi-symmetric flow and four beta meso-scale *** complex structure is characterized by a fine pattern,which contains seven closed systems with spatial scales of less than 100 km,embedded in a positive flux wave train and a negative wave train,*** average wind speed decreased with time in the positive flux region,but was nearly unchanged in the negative flux *** pattern reveals the evolutionary asymmetry and localization of wind speed of the major *** track of the major vortex center has a trend toward the center of the negative flux center,indicating that there is a certain relation between the complex structure of the energy transfer flux and the motion of the major vortex *** results imply that the formation and evolution of the fine and complex structure should be attributed to the nonlinear interaction between the vortices at different spatial scales.

关键词： vortex complex structure non-linear interaction energy cascade

Numerical simulation of Meiyu front and the diagnosis of moist vorticity vector

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Progress in Natural Science:Materials International 2007年第11期17卷 1341-1347页

作者： Ping Fan1,2 and Luo Zhexian2(1. institute of Atmospheric physics, Chinese Academy of Sciences, Beijing 100029, china 2. Nanjing university of information Sciences & Technology, Nanjing 210044, china) institute of Atmospheric physics Chinese Academy of Sciences Beijing 100029 China Nanjing university of information Sciences & Technology Nanjing 210044 China

Moist vorticity vector is introduced to study the development and evolution of mesoscale convective vortex (MCV) in the Meiyu front precipitation with the Advanced Regional Predication System (ARPS). In this study, the heavy rainfall is simulated to investigate the genesis, development and dissipation of middle scale convective vortex, which occurred from 0000 UTC 3 July to 1200 UTC 5 July over the Jianghuai River valley. Moist vorticity vector (MVV) has zonal, radial and vertical components in its 3D spatial distribution. The simulation shows that the vertical component of moist vorticity vector well demonstrates the spatial distribution characteristics of middle scale convective vortex, especially in the process of Meiyu front precipitation. Diagnosis upon zonal, radial averaged and mass-integrated quantities of MVV shows that its vertical component and the surface precipitating ratio are in phase with a correlation coefficient of 0.68, indicating that the vertical component of MVV is closely associated with the Meiyu front precipitation. In addition, the tendency of the vertical component of MVV is mainly determined by the interaction between the vorticity and the zonal and radial gradient of condensational or depositional heating.

关键词： moist vorticity vector mesoscale convective vortex Meiyu front precipitation

An all-silicone zoom lens in an optical imaging system

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Chinese physics B 2013年第9期22卷 465-469页

作者：赵存华 College of physics and Electronic information Luoyang Normal University Luoyang Key Laboratory of Laser Spectrum Technology institute of Modern Optics Luoyang Normal University

An all-silicone zoom lens is fabricated. A tunable metal ringer is fettered around the side edge of the lens. A nylon rope linking a motor is tied, encircling the notch in the metal ringer. While the motor is operating, the rope can shrink or release to change the focal length of the lens. A calculation method is developed to obtain the focal length and the zoom ratio. The testing is carried out in succession. The testing values are compared with the calculated ones, and they tally with each other well. Finally, the imaging performance of the all-silicone lens is demonstrated. The all-silicone lens has potential uses in cellphone cameras, notebook cameras, micro monitor lenses, etc.

关键词： micro lens silicone lens zoom optical system

Transition of Growth Mode in Homoepitaxy on Metal Surface

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Communications in theoretical physics 2007年第7期48卷 175-178页

作者： WU Li-Li LU Hang-Jun WU Feng-Min College of Mathematics and physics,information Engineering,Zhejiang Normal university,Jinhua 321004,china College of Mathematics and physics Information Engineering Zhejiang Normal University

The process of the multilayer growth of Pt on Pt(111)is studied by using a Monte Carlo model with realisticphysical *** effects of the substrate temperature,the ES barrier,and the deposition rate on the growthmode have been *** transitions of the surface roughness from oscillatory to non-oscillatory behaviorand then back to oscillatory behavior are observed while increasing the substrate temperature from 270 K to 620 *** found that the growth mode depends strongly on ES barrier over the whole temperatures and the deposition rate ofatoms effectively affects the growth *** simulation results are consistent with many experimental observationsfor homoexpitaxy on a Pt(111)substrate.

关键词： growth mode transition Monte Carlo simulation surface roughness oscillation

The first-principles study on the doping effect of Re in Ni3Al

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Progress in Natural Science:Materials International 2008年第7期18卷 861-866页

作者： Song Yu a,*, Chongyu Wanga,b, Tao Yua aCentral Iron and Steel Research institute, Beijing 100081, china bDepartment of physics, Tsinghua university, Beijing 100084, china Central Iron and Steel Research institute Beijing 100081 China Department of physics Tsinghua University Beijing 100084 China

Using first-principles density function for molecules method (DMol) and discrete variational method (DVM) based on the density functional theory, we studied the doping effect of Re in Ni3Al. The structure relaxation and the alloying energy show that Re has a strong Al site preference and leads to the local deformation, which is in agreement with the experimental results and other theoretical results. In addition, the charge density diffierence and the bond order show that Re can strongly enhance the interatomic interaction between the nearest neighbor atoms. From the density of states and the Pauli spectrum, we find that resonance states and localized states are induced by doping Re, and the doped Re atom forms the hybridized bond with the nearest neighbor atoms.

关键词： The first-principles Re Ni3Al

Efficient generation of two-dimensional cluster states in a cavity QED

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Chinese physics B 2013年第4期22卷 124-127页

作者：张刚周建薛正远 Machinery and Electronics Engineering institute West Anhui University Anhui Xinhua university Laboratory of Quantum information Technology and school of physics and Telecommunication Engineering South China Normal University

We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state of the cavity. In particular, we have managed to avoid the conventional dispersive coupling so that high speed gate operation is achieved which is very important in view of decoherence. We show that this multipartite pair-wise controlled phase operation makes the generation of two-dimensional cluster states very efficient.

关键词： controlled phase gate cluster state cavity QED

A novel method of systematic error compensation for a position and orientation system

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Progress in Natural Science:Materials International 2008年第8期18卷 953-963页

作者： Xiuxiao Yuan* school of Remote Sensing and information Engineering, Wuhan university, Wuhan 430079, china school of Remote Sensing and information Engineering Wuhan University Wuhan 430079 China

A novel method is introduced for self-calibration and elimination of systematic errors for a position and orientation system (POS). The method uses a combined bundle block adjustment with POS data (named the POS-supported bundle block adjustment) without a calibration field. On the basis of delivering strict observation equations for POS data, the specific scheme of compensating the translation and drift systematic errors in a POS is given, and a prototype system WuCAPS is developed. The effects of eliminating POS systematic errors using the POS-supported bundle block adjustment for different ground control conditions are tested using two sets of actual aerial photos. The first set was taken over a flat region in the suburbs of the city of Yingkou in china and tested at a scale of 1:2500. The second set was taken over a high mountainous region in the desert region of Xinjiang in china and tested at a scale of 1:32,000. The empirical results verified that the POS systematic errors can be completely eliminated and the photo elements of exterior orientation obtained by the POS-supported bundle block adjustment can satisfy the requirements of aerial photogrammetric topographic mapping when four full ground control points (GCPs) are emplaced in the corners of the adjustment block for large-scale images of flat regions, but only one full GCP emplaced in the center of the adjustment block is needed for medium-small scale images of mountainous regions. This not only demonstrates the validity of the established mathematical model and the feasibility of the method proposed in this paper, but also avoids the use of a special calibration field. Therefore, it can simplify the existing POS operation rules and dramatically save on practical application costs, laying the theoretical foundation for widespread use of POS.

关键词： Position and orientation system (POS) Systematic error POS-supported bundle block adjustment Self-calibration Accuracy

Response synchronization: New progress in brain-visual information processing

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Chinese Science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. State Key Laboratory of Atmospheric Boundary Layer physics and Atmospheric Chemistry , institute of Atmospheric physics , Chinese Academy of Sciences , Beijing 100029, china 2. Commission of the National Natural Science Foundation of china , Beijing 100083, china 3. The Center of information Science , Peking university, Beijing 100871, china 4. Open Laboratory of Visual information Processing , institute of Biophysics , Chinese Academy of Sciences , Beijing 100101, china State Key Laboratory of Atmospheric Boundary Layer physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National Natural Science Foundation of china Beijing China The Center of information Science Peking University Beijing China Open Laboratory of Visual information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. Naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

Electrical property of 8-mol% yttria-stabilized zirconia electrolyte by spark-plasma sintering

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Science china(Technological Sciences) 2004年第5期47卷 569-576页

作者： JIAN Jiawen1,2, CHANG Aimin3, YANG Bangchao2 & ZHANG Yikang4 1. The school of information Science Engineering, Ningbo university, Ningbo 315211, china 2. The school of Microelectronics and Solid-state Electronics, university of Electronic Science and Tech-nology of china, Chengdu 610054, china 3. The Xinjiang Technical institute of physics and Chemistry, Chinese Academy of Sciences, Urumqi 830022, china 4. Hongtak (Chengdu) Electronic Co., Ltd, Chengdu 610041, china Correspondence should be addressed to Jian Jiawen 1. The school of information Science Engineering Ningbo University 315211 Ningbo China 2. The school of Microelectronics and Solid-state Electronics University of Electronic Science and Technology of China 610054 Chengdu China 3. The Xinjiang Technical institute of physics and Chemistry Chinese Academy of Sciences 830022 Urumqi China 4. Hongtak (Chengdu) Electronic Co. Ltd 610041 Chengdu China

Spark-plasma sintering (SPS) process was used to sinter ZrO2 (8Y) powders, and a relative density of 99% has been reached at a low temperature (1350°C) and short dwelling time (10 min) compared to the conventional sintered identical samples (1450°C 4 h)(CS). By the X-ray diffraction (XRD) patterns, the microstructure of the SPS pellet and CS pellet are both indexed by the cubic unit cell (Fm3m). The finer crystallite size (D111) of the SPS pellet is 154 nm and D111 of the CS pellet is more than 1 μm. The AC impedance spectroscopy shows that the ionic conductivity of SPS pellet is different from that of CS pellet. The activation energy for the SPS ceramics, estimated from the slope in the range of 400–800°C, was 91 kJ mol?1, which is in good agreement with CS pellet (96 kJ mol?1), indicating that the conduction mechanism in SPS ceramics is similar to that in CS ceramics.

关键词： yttria-stabilized zirconia electrolyte, spark-plasma sintering, AC impedance.