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Heterogeneous reaction of NO_2 with sea salt particles

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Science China Chemistry 2010年第12期53卷 2652-2656页

作者： YE ChunXiang 1,LI HongJun 1,zhu Tong 1,SHANG Jing 1,ZHANG ZeFeng 1,2 & ZHAO DeFeng 1 1 State Key Joint Laboratory of Environmental Simulation and Pollution Control college of Environmental Sciences and engineering,Peking University,Beijing 100871,China 2 college of Atmospheric Physics,Nanjing University of information Science and Technology,Nanjing 210044,China State Key Joint Laboratory of Environmental Simulation and Pollution Control college of Environmental Sciences and engineering Peking University Beijing China college of Atmospheric Physics Nanjing University of Information Science and Technology Nanjing China

To understand how NO2 reacts with sea salt particles in the atmosphere of Mega-cities in coastal zones,the heterogeneous reaction of NO2 on the surface of wet sea salt was investigated with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC).Kinetic measurements indicated that nitrate formation on sea salt was second order in NO 2 concentration and reactive uptake coefficients were (5.51 ± 0.19) × 10-7 and 1.26 × 10-6 respectively under 0% and 20% relative humidity (RH) at NO 2 molecular concentration of 1.96 × 1015 mol/*** results showed that liquid water was formed at the site of MgCl2·6H2O,CaCl2·2H2O on the surface of sea salt and made the reaction more sustainable by releasing hydrated water and absorbing water from air even under a low RH (30%).Therefore,pure NaCl particles should not be used to represent sea salt in studies of the heterogeneous reaction with NO2.

关键词： sea salt particles diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) hydrated water absorbed water reactive uptake coefficient

MMSE relay precoding schemes based on quantization error compensation for multi-relay system

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Science China(information Sciences) 2010年第12期53卷 2548-2556页

作者： LI Ting 1,2 & YANG LuXi 2 1 college of Communication and information engineering,Nanjing University of Posts and Telecommunications,Nanjing 210003,China 2 School of information Science and engineering,Southeast University,Nanjing 210096,China college of Communication and information engineering Nanjing University of Posts and Telecommunications Nanjing China School of information Science and engineering Southeast University Nanjing China

In order to deal with the performance degradation resulting from the quantization error,this paper introduces the statistics of Grassmannian codebook's quantization error into relay precoding design for multirelay *** on the two-step MMSE optimization algorithm for relay precoding and receiver equalizing with full feedback under QoS requirements,we first propose a limited feedback two-step MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation,and then we propose a limited feedback joint MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation subject to a global power constraint at the output of *** results show that the proposed joint MMSE optimization scheme with quantization error compensation has a much lower bit-error rate than the two-step MMSE optimization scheme with quantization error compensation and the joint MMSE optimization scheme without quantization error compensation.

关键词： multi-relay precoding limited feedback minimum mean square error

Analytical Potential Energy Function,Spectroscopic Constants and Vibrational Levels for A^1E_u^+ State of Dimer ~7Li_2

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Communications in Theoretical Physics 2007年第12期48卷 1081-1087页

作者： SHI De-Heng~1 MA Heng~1 SUN Jin-Feng~(1,2)and zhu Zun-Lue~1~1 college of Physics & information engineering,Henan Normal University,Xinxiang 453007,China~2 Department of Physics & Electron Science,Luoyang Normal University,Luoyang 471022,China college of Physics & information engineering Henan Normal University Xinxiang 453007 China Department of Physics & Electron Science Luoyang Normal University Luoyang 471022 China

The symmetry-adapted-duster configuration-interaction method is used to investigate the spectroscopicproperties of ~7Li_2(A^1∑_u^+) over the internuclear distance ranging from 2.4ao to *** complete potential energycurves are calculated at numbers of basis *** the ab initio calculated points are fitted to the analytic MurrellSorbie function and then employed to compute the spectroscopic *** comparison,the spectroscopic constantsreproduced by the potential attained at D95(3df,3pd) are found to be very close to the experiments,a^d the values (T_e,D_e,R_e,ω_e,ω_eχ_e,α_e and B_e) are of 1.732 93 eV,1.161 36 eV,0.313 27 nm,251.95 cm^(-1),1.623 cm^(-1),0.005 35 cm^(-1),and0.490 cm^(-1),*** the potential obtained at D95(3df,3pd),the totally 75 vibrational states are found whenJ=*** vibrational levels,the classical turning points and the inertial rotation constants of the first 68 vibrationalstates are calculated for the first time and compared with the available *** agreement is *** centrifugal distortion constants of the first 32 vibrational states are also reported for the first *** reasonabledissociation limit for ~7Li_2(A^1∑_u^+) is deduced using the calculated results at present.

关键词： analytic potential energy function harmonic frequency dissociation energy vibrational level classical turning point

Resolution method for overlapping peaks based on the fractional-order differential

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Science China Chemistry 2007年第6期50卷 797-805页

作者： LI YuanLu1, YU ShengLin2 & ZHENG Gang2 1 college of information & Control, Nanjing University of information Science & Technology, Nanjing 210044, China 2 college of Automation engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China college of information & Control Nanjing University of Information Science & Technology Nanjing China college of Automation engineering Nanjing University of Aeronautics and Astronautics Nanjing China

Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals.

关键词： fractional-order differentiation filter, fractional-order differential, overlapping peaks, voltammetric peak

An improved network layer protocol based on mobile IPv6

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Journal of Central South University 2001年第4期8卷 263-267页

作者： WANG Jian xin 1,HUANG Guo sheng 2,CHEN Song qiao 1,CHEN Jian er 1 (1.college of information Science and engineering, Central South University, Changsha 410083, China 2.Department of Physics and Electronic engineering, Jishou University, Jisho college of information Science and engineering Central South University Changsha China Department of Physics and Electronic engineering Jishou University Jishou China

The mobile IPv6 proposed by the IETF aims at providing mobility support on the next generation Internet. First, the authors described the basic principle of mobile IPv6 in brief and analyzed the advantages and disadvantages of it, presented a new idea of allocating a specific address space for mobile node (MN) and developed a new extension header and two ICMP message types for mobile IPv6. Lastly the authors proposed an optimization strategy for mobile IPv6 based on these extensions of protocol, which has the following advantages: 1) It is more convenient to manage the MNs because MN can be judged from its IP address; 2) When the correspondent node (CN) is not actively communicating with a MN, the MN and its home agent (HA) need not send Binding Update to the CN, and the CN need not send Binding Request to the MN. Only when the CN really wants to send a packet to the MN, will the CN voluntarily send a MN Discovery Request message to acquire the MN′s care of address. In this way,the transmission of Binding Update and Binding Request is greatly reduced, consequently the network overhead is also decreased; 3) While sending packets, the CN simply uses a MN Home Address Extension Header without using IPinIP encapsulation and routing header, which can reduce the redundant information in the packet and the message delay; 4) All the packets sent by the CN can be directly routed to the MN and the triangle routing can be completely avoided. By using these protocol extensions, the overhead of the network is greatly reduced and the network quality of services (QoS) is improved.

关键词： mobile IP home agent mobile node care of address binding

Direct gray-scale extraction of topographic features for vein recognition

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Science China(information Sciences) 2010年第10期53卷 2062-2074页

作者： KANG WenXiong 1, LI HuaSong 2 & DENG FeiQi 1 1 college of Automation Science and engineering, South China University of Technology, Guangzhou 510640, China 2 School of information engineering, Wuyi University, Jiangmen 529000, China college of Automation Science and engineering South China University of Technology Guangzhou China School of information engineering Wuyi University Jiangmen China

Binarization processing is a key step in most vein pattern recognition, but may create flaws such as leakage of some feature information. In order to overcome this problem, a new approach is explored in this paper which can extract topographic features directly from gray-scale vein images without binarization processing. First, an extreme graph of directional fields (EGDF) is calculated according to neighborhood information of every pixel, and then the intravenous main ridge of the image can be separated step by step from EGDF with the defined constraint template sets. After that, the sub-ridge is extracted from end points of the main ridge in range constraint image with the tracing method of maximal neighboring point. According to contrast experiment the proposed method is better than the traditional processing (performing binarization first and then skeletonization), in that it can overcome the problem that some separate vein lines are extracted incorrectly, and it can avoid extracting two neighboring vein lines as one ridge. As such, the proposed method is an effective way to extract topographic features for vein recognition

关键词： vein recognition feature extraction directional fields

On the use of deep learning for phase recovery

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Light(Science & Applications) 2024年第2期13卷 190-235页

作者： Kaiqiang Wang Li Song Chutian Wang Zhenbo Ren Guangyuan Zhao Jiazhen Dou Jianglei Di George Barbastathis Renjie Zhou jianlin Zhao Edmund Y.Lam Department of Electrical and Electronic engineering The University of Hong KongHong Kong SARChina School of Physical Science and Technology Northwestern Polytechnical UniversityXi’anChina Department of Biomedical engineering The Chinese University of Hong KongHong Kong SARChina School of information engineering Guangdong University of TechnologyGuangzhouChina Department of Mechanical engineering Massachusetts Institute of TechnologyCambridgeMAUSA

Phase recovery(PR)refers to calculating the phase of the light field from its intensity *** exemplified from quantitative phase imaging and coherent diffraction imaging to adaptive optics,PR is essential for reconstructing the refractive index distribution or topography of an object and correcting the aberration of an imaging *** recent years,deep learning(DL),often implemented through deep neural networks,has provided unprecedented support for computational imaging,leading to more efficient solutions for various PR *** this review,we first briefly introduce conventional methods for ***,we review how DL provides support for PR from the following three stages,namely,pre-processing,in-processing,and *** also review how DL is used in phase image ***,we summarize the work in DL for PR and provide an outlook on how to better use DL to improve the reliability and efficiency of ***,we present a live-updating resource(https://***/kqwang/phase-recovery)for readers to learn more about PR.

关键词： networks phase optics

A single observer location method under the scatter signals position disturbance situation:the constraint total least square method

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Science China(information Sciences) 2011年第1期54卷 146-152页

作者： YANG TianChi1,YU ChaoQun2,WANG TianPeng1 & JIN Liang1 1National Digital Switching System engineering and Technological Research Center, Zhengzhou 450002,China 2Surveying and Mapping college of information engineering University, Zhengzhou 450002,China National Digital Switching System engineering and Technological Research Center Zhengzhou China Surveying and Mapping college of information engineering University Zhengzhou China

A target position can be estimated using position information from scattered signals in the nonline-of-sight propagation environment in a single observer location *** is always an error in the final estimated result of the position obtained using scatter signals because measurement noise is *** reduce the total error of the system,we propose a method of converting the problem of optimizing location into a one of solving the extremes of the *** the problem of how to solve the extremes of the constraints is converted into an unconstrained problem by using the constrained total least squares(CTLS) ***,the Newton iteration method is used to obtain the optimized *** results also verify the capability of this method.

关键词： scatter position disturbing VOCTLS single observer location Newton iteration

Extraction of vegetation fraction information from CBERS images based on VBSI vegetation index in Kaixian county

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中国有色金属学会会刊：英文版 2011年第S3期21卷 712-716页

作者： GAO Zhi-fang1, NIU Hai-peng1, LIU Jin-ping2 1. college of Surveying and Land information engineering, Henan Polytechnic University, Jiaozuo 454000, China 2. college of Geographic Sciences, Chongqing Normal University, Chongqing 400047, China college of Surveying and Land information engineering Henan Polytechnic University Jiaozuo 454000 China college of Geographic Sciences Chongqing Normal University Chongqing 400047 China

Based on the mixed pixel model, the vegetation fraction of Kaixian county, China, was extracted with three free CBERS images. VBSI vegetation index suitable for CBERS images constructed with FCD (forest canopy density) model principle was put forward by ITTO (International Tropical Timber Organization) was used, considering the underestimation of vegetation fraction using NDVI in low mountain-hill region influenced by soils and shadows. And vegetation fraction was divided into five categories from low to high in order to study the special variation of vegetation cover. The results show that the vegetation cover of the region is overall good, with an average of 50%. The area of vegetation fraction below 30% accounts for 11.7% of the entire studied area, mainly concentrates in central eastern Kaixian county, where is the major development zone of cities and towns; that between 30% and 60% accounts for 62%; and that higher than 60% accounts for 26%, and mostly locates in northern middle-mountain area.

关键词： VBSI vegetation index mixed pixel model FCD model CBERS