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Journal of Environmental Sciences 2004年第6期16卷 981-986页

作者： LILian-fang liguo-xue LIAOXiao-yong CollegeofResourcesandEnvironmentalSciences ChineseAgriculturalUniversityBeijing100094China InstituteofGeographicalSciencesandNaturalResourcesResearch ChineseAcademyofSciencesBeijing100101China

This paper presented the characteristics of nitrogen and phosphorus pollution in Beijing surface water during the survey. A significant difference was found out in concentration distribution of various parameters of nitrogen and phosphorus. Most water bodies in five water systems were polluted by total nitrogen with the content even up to 120 mg/L which was higher than exceeded the fifth class standard of national surface water quality standard GB3838-2002 except for several segments of Chaobaihe and Yongdinghe. Ammonia and phosphorus showed a similar tendency of distribution with higher content in Daqinghe, Beiyunhe and Jiyunhe water systems, but with relatively low concentrations in Chaobaihe and Yongdinghe water systems. Meanwhile, nitrate was found at comparatively low content(mostly less than 10 mg/L) and could fit for corresponding water quality requirements. Totally, the water quality of Daqinghe, Jiyunhe and Beiyunhe river systems as well as the lower reaches of Yongdinghe and Chaobaihe was contaminated seriously with high content of total nitrogen and phosphorus. Through multivariate statistical approaches, it can be concluded that total nitrogen, ammonia and total phosphorus was highly correlated to chemical oxygen demand, biochemical oxygen demand, dissolved oxygen and electrical conductivity, which explained the same pollution source from anthropogenic activities.

关键词： surface water nitrogen phosphorus assessment GIS

Membrane protein reconstitution for functional and structural studies

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Science China(Life Sciences) 2015年第1期58卷 66-74页

作者： WANG liguo TONGGU LiGe Department of Biological Structure University of Washington

Membrane proteins are involved in various critical biological processes,and studying membrane proteins represents a major challenge in protein *** shown by both structural and functional studies,the membrane environment plays an essential role for membrane *** vitro studies are reliant on the successful reconstitution of membrane *** review describes the interaction between detergents and lipids that aids the understanding of the reconstitution *** the techniques of detergent removal and a few useful techniques to refine the formed proteoliposomes are *** the applications of reconstitution techniques to study membrane proteins involved in Ca2+ signaling are summarized.

关键词： membrane protein reconstitution Ca2+ signaling Ca2+ mediators Ca2+-regulated enzymes Ca2+ transducers

Microbial community dynamics at high organic loading rates revealed by pyrosequencing during sugar refinery wastewater treatment in a UASB reactor

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Frontiers of Environmental Science & Engineering 2018年第4期12卷 33-44页

作者： liguo Zhang Qiaoying Ban Jianzheng Li College of Environmental and Resource Sciences Shanxi Universily Taiyuan 030000 China State Key Laboratory of Urban Watel Resource and Environment School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150000 China＊

The performance and rnicrobial community structure in an upflow anaerobic sludge blanket reactor （UASB） treating sugar refinery wastewater were investigated. The chemical oxygen demand （COD） removal reached above 92.0% at organic loading rates （OLRs） of 12.0-54.0 kgCOD/（m^3· d）. The volatile lhtty acids （VFAs） in effluent were increased to 451.1 mg/L from 147.9 mg/L and the specific methane production rate improved by 1.2 2.2-1bid as the OLR increased. The evolution of microbial comnmnities in anaerobic sludge at three different OLRs was investigated using pyrosequencing. Operational taxonomic units （OTUs） at a 3% distance were 353,337 and 233 for OLRI2, OLR36 and OLR54, respectively. When the OLR was increased to 54.0 kgCOD/（m^3· d） from 12.0 kgCOD/ （m^3· d） by stepwise, the microbial community structure were changed significantly. Five genera （Bacteroides, Trichococcus, Cho,seobacterium, Longilinea and Aerococcus） were the dominant fermentative bacteria at the OLR 12-0 kgCOD/（m^3· d）. However, the sample of OLR36 was dominated by Lacmcoccus, Trichococcus, Anaer-arcus and Veillonella. At the last stage （OLR = 54.0 kgCOD/ （m^3· d）, the diversity and percentage of femlentative bacteria were markedly increased. Apart from fermentative bacteria, an obvious shift was observed in hydrogen-producing acetogens and non- acetotrophic methanogens as OLR increased. Svntrophohacter, Geobacter and Methanomethylovor- ans were the dominant hydrogen-producing acetogens and methylotrophic methanogens in the samples of OLRI2 and OLR36. When the OLR was increased to 54.0 kgCOD/（m^3· d）, the mare hydrogen-producing acetogens and hydrogenotrophic methanogens were substituted with Destd/bvi- brio and Methanospillum. However, the composition of acetotrophic methanogens （Methanosaeta） was relatively stable during the whole operation period of the UASB reactor.

关键词： Upflow anaerobic sludge blanket Sugar refinery wastewater Organic loading rate Pyrosequencing Microbial community structure

HIV-1 immunopathogenesis in humanized mouse models

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Cellular & Molecular Immunology 2012年第3期9卷 237-244页

作者： liguo Zhang Lishan Su Key Laboratory of Immunity and Infection Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China Lineberger Comprehensive Cancer Center Department of Microbiology and Immunology School of Medicine University of North Carolina at Chapel Hill Chapel Hill NC USA

In recent years, the technology of constructing chimeric mice with humanized immune systems has markedly improved. Multiple lineages of human immune cells develop in immunodeficient mice that have been transplanted with human hematopoietic stem cells. More importantly, these mice mount functional humoral and cellular immune responses upon immunization or microbial infection. Human immunodeficiency virus type I （HIV-1） can establish an infection in humanized mice, resulting in CD4＋ T-cell depletion and an accompanying nonspecific immune activation, which mimics the immunopathology in HIV-l-infected human patients. This makes humanized mice an optimal model for studying the mechanisms of HIV-1 immunopathogenesis and for developing novel immune-based therapies.

关键词： HIV humanized mice pathogenesis immune activation

Integration of spatial attractions between and within pixels for sub-pixel mapping

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Journal of Systems Engineering and Electronics 2012年第2期23卷 293-303页

作者： Qunming Wang liguo Wang Danfeng Liu College of Information and Communications Engineering Harbin Engineering UniversityHarbin 150001E R.China

As a promising technique to enhance the spatial reso- lution of remote sensing imagery, sub-pixel mapping is processed based on the spatial dependence theory with the assumption that the land cover is spatially dependent both within pixels and be- tween them. The spatial attraction is used as a tool to describe the dependence. First, the spatial attractions between pixels, sub- pixel/pixel spatial attraction model （SPSAM）, are described by the modified SPSAM （MSPSAM） that estimates the attractions accord- ing to the distribution of sub-pixels within neighboring pixels. Then a mixed spatial attraction model （MSAM） for sub-pixel mapping is proposed that integrates the spatial attractions both within pix- els and between them. According to the expression of the MSAM maximumising the spatial attraction, the genetic algorithm is em- ployed to search the optimum solution and generate the sub-pixel mapping results. Experiments show that compared with SPSAM, MSPSAM and pixel swapping algorithm modified by initialization from SPSAM （MPS）, MSAM can provide higher accuracy and more rational sub-pixel mapping results.

关键词： remote sensing imagery sub-pixel mapping mixed spatial attraction model (MSAM) genetic algorithm (GA).

Input-to-state stability of coupled hyperbolic PDE-ODE systems via boundary feedback control

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Science China(Information Sciences) 2019年第4期62卷 88-99页

作者： liguo ZHANG Jianru HAO Junfei QIAO Faculty of Information Technology Beijing University of Technology Key Laboratory of Computational Intelligence and Intelligent Systems

We herein investigate the boundary input-to-state stability(ISS) of a class of coupled hyperbolic partial differential equation-ordinary differential equation(PDE-ODE) systems with respect to the presence of uncertainties and external disturbances. The boundary feedback control of the proportional type acts on the ODE part and indirectly affects the hyperbolic PDE dynamics via the boundary input. Using the strict Lyapunov function, some sufficient conditions in terms of matrix inequalities are obtained for the boundary ISS of the closed-loop hyperbolic PDE-ODE systems. The feedback control laws are designed by combining the line search algorithm and polytopic embedding techniques. The effectiveness of the designed boundary control is assessed by applying it to the system of interconnected continuous stirred tank reactor and a plug flow reactor through a numerical simulation.

关键词： hyperbolic PDE-ODE systems input-to-state stability boundary control Lyapunov function PFR-CSTR models

Grid Generation and Numerical Analysis of Multi-Stream Flow in the Complex Channel with a Forced Mixer Lobe

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Journal of Thermal Science 2004年第2期13卷 167-173页

作者： Suofang Wang liguo Li Jingzhou Zhang Nanjing Univ Aeronaut & Astronaut Coll Energy & Power Engn Nanjing 210016 Jiangsu Peoples R China

The co-located grid, SIMPLEC and Chen-Kim modified k - E turbulence model are applied to investigate numerically the multi-stream flow and temperature fields in the complex channel with a forced mixer lobe at room temperature and at elevated temperature. The body-fitted coordinate grids are generated respectively in sub-domains according to the shapes of the channel by solving Poisson’s equations to compose the whole grid of the domain. The large viscosity, linear and simultaneous under-relaxation factors are used to solve the coupling of fluid and solid. The solid grid is complemented at the upper inlet of the secondary flow to keep the same node number at the inlet and at double-wall sub-domains. The numerical results and experimental data show good agreement at room temperature. It is illustrated that the cooling air ejected into the slot between the double plates decreases the temperature of the wall.

关键词： body-fitted coordinate multi-stream flow lobe ejector double-wall.

Impact of data set noise on distributed deep learning

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The Journal of China Universities of Posts and Telecommunications 2020年第2期27卷 37-45页

作者： Guo Qinghao Shuai liguo Hu Sunying School of Mechanical Engineering Southeast UniversityNanjing 211100China

The training efficiency and test accuracy are important factors in judging the scalability of distributed deep *** this dissertation,the impact of noise introduced in the mixed national institute of standards and technology database(MNIST)and CIFAR-10 datasets is explored,which are selected as benchmark in distributed deep *** noise in the training set is manually divided into cross-noise and random noise,and each type of noise has a different ratio in the *** the premise of minimizing the influence of parameter interactions in distributed deep learning,we choose a compressed model(SqueezeNet)based on the proposed flexible communication *** is used to reduce the communication frequency and we evaluate the influence of noise on distributed deep training in the synchronous and asynchronous stochastic gradient descent *** on the experimental platform TensorFlowOnSpark,we obtain the training accuracy rate at different noise ratios and the training time for different numbers of *** existence of cross-noise in the training set not only decreases the test accuracy and increases the time for distributed *** noise has positive effect on destroying the scalability of distributed deep learning.

关键词： distributed deep learning stochastic gradient descent parameter server(PS) dataset noise

Recurrent neural network for vehicle dead-reckoning

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Journal of Systems Engineering and Electronics 2008年第2期19卷 351-355页

作者： Ma Haibo Zhang liguo Chen Yangzhou School of Electronic Control Engineering Beijing Univ. of Technology Beijing 100022 P. R. China

For vehicle integrated navigation systems, real-time estimating states of the dead reckoning （DR） unit is much more difficult than that of the other measuring sensors under indefinite noises and nonlinear characteristics. Compared with the well known, extended Kalman filter （EKF）, a recurrent neural network is proposed for the solution, which not only improves the location precision and the adaptive ability of resisting disturbances, but also avoids calculating the analytic derivation and Jacobian matrices of the nonlinear system model. To test the performances of the recurrent neural network, these two methods are used to estimate the state of the vehicle＇s DR navigation system. Simulation results show that the recurrent neural network is superior to the EKF and is a more ideal filtering method for vehicle DR navigation.

关键词： dead reckoning extended Kalman filter recurrent neural network vehicle integrated navigationsystems.

A surface-based hiding function linking flume and field data

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Science China(Technological Sciences) 2017年第10期60卷 1560-1569页

作者： ZHANG liguo FU XuDong DUAN Jennifer G State Key Laboratory of Hydroscience and Engineering Tsinghua University Department of Civil Engineering and Engineering Mechanics University of Arizona

The quantification of the sheltering and exposure effects of non-uniform sediments has been widely achieved through hiding function models. Big challenge exists so far in the model parameter that is highly variable and differs greatly between laboratory flumes and field streams. This paper presents an improved surface-based hiding fimction. The force balance for particle inception was formulated and the allocation of the overall bed shear stress into each group of sediments was mimicked. The new hiding function was examined against and agrees well with the documented field and flume data. It was shown that the hiding fimction is closely related to the relative flow depth and the reference elevation in the velocity profile in addition to the bed material gradation. The power law of velocity profile that applies to both flume flows and natural streams can link the flume and field data together. The hiding function with b = 1/6 and b = 1/2 is applicable to natural streams and laboratory flumes, respectively. The value orb = 0.263 also works well for gravel bed rivers. The range of the reference elevation, namely z0 = 0.4Dm-1.4Dm, is recommended for either the flume or field data. The new hiding function contributes to addressing clearer physical meanings and a useful perspective for further improvement.

关键词： hiding function relative flow depth flume and field data reference elevation