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Graph Theory Methods for Decomposition w.r.t. Outputs of Boolean Control Networks

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Journal of Systems Science & Complexity 2017年第3期30卷 519-534页

作者： zou Yunlei ZHU Jiandong College of Mathematical Sciences Yangzhou University Institute of Mathematics School of Mathematical Sciences Nanjing Normal University

This paper focuses graph theory method for the problem of decomposition w.r.t. outputs for Boolean control networks(BCNs). First, by resorting to the semi-tensor product of matrices and the matrix expression of BCNs, the definition of decomposition w.r.t. outputs is introduced. Second, by referring to the graphical structure of BCNs, a necessary and sufficient condition for the decomposition w.r.t. outputs is obtained based on graph theory method. Third, an effective algorithm to realize the maximum decomposition w.r.t. outputs is proposed. Finally, some examples are addressed to validate the theoretical results.

关键词： Boolean control network decomposition w.r.t outputs semi-tensor product.

Theoretical solution for displacement and stress in strain-softening surrounding rock under hydraulic-mechanical coupling

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Science China(Technological Sciences) 2015年第8期58卷 1401-1413页

作者： zou JinFeng LI ShuaiShuai School of Civil Engineering Central South University

This study focuses on the stress and displacement of a circular opening that is excavated in a strain-softening rock mass under hydraulic-mechanical *** follows the generalized Hoek-Brown(H-B) failure ***,an improved numerical method and stepwise procedure are *** method considers the deterioration of the strength,deformation,and dilation *** also incorporates the hydraulic-mechanical coupling and the variation of elastic strain in the plastic *** examples are conducted to demonstrate the validity and accuracy of the proposed solution through MATLAB programming and FLAC *** studies are also conducted to highlight the influence of hydraulic–mechanical coupling on stress and *** show that in this case,stress confinement is lower and tunnel convergences are higher than the corresponding stresses and displacements obtained when those factors are not *** displacement and plastic radius are also larger than those obtained when hydraulic-mechanical coupling is not considered.

关键词： strain softening hydraulic-mechanical coupling numerical stepwise procedure circular opening

Water quality evaluation based on improved fuzzy matter-element method

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Journal of Environmental Sciences 2012年第7期24卷 1210-1216页

作者： Dongjun Liu Zhihong zou School of Economics and Management Beihang UniversityBeijing 100191China

For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. The coefficient of variation of each indicator is used to determine the weight instead of traditional calculating superscales method. On the other hand, fuzzy matter-elements are constructed, and normal membership degrees are used instead of traditional trapezoidal ones. The composite fuzzy matter-elements with associated coefficient are constructed through associated transformation. The levels of natural water quality are determined according to the principle of maximum correlation. The improved fuzzy matter-element evaluation method is applied to evaluate water quality of the Luokou mainstream estuary at the first ten weeks in 2011 with the coefficient of variatiola method determining the weights. Water quality of Luokou mainstream estuary is dropping from level I to level II. The results of the improved evaluation method are basically the same as the official water quality. The variation coefficient method can reduce the workload, and overcome the adverse effects from abnormal values, compared with the traditional calculating superscales method. The results of improved fuzzy matter- element evaluation method are more credible than the ones of the traditional evaluation method. The improved evaluation method can use information of monitoring data more scientifically and comprehensively, and broaden a new evaluation method for water quality assessment.

关键词： water quality improved fuzzy matter-element evaluation method synthetic evaluation variation coefficient method normal membership Key words: water quality improved fuzzy matter-element evaluation method synthetic evaluation variation coefficient method normal membership

Nitrogen-doped amorphous carbon coated mesocarbon microbeads as excellent high rate Li storage anode materials

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Journal of Materials Science & Technology 2019年第4期35卷 644-650页

作者： Zhimin zou Chunhai Jiang Fujian Provincial Key Laboratory of Functional Materials and Applications Institute of Advanced Energy MaterialsSchool of Materials Science and EngineeringXiamen University of Technology

A composite anode material consisting of a stable inner core of mesocarbon microbeads and a porous nitrogen-doped amorphous carbon shell active for lithium storage is prepared. The thin birnessite MnO_2 nanosheets hydrothermally deposited on mesocarbon microbeads are in situ replaced by polypyrrole,which is then transformed to nitrogen-doped amorphous carbon layer by calcination in nitrogen atmosphere. The surface modified mesocarbon microbeads exhibit average discharge capacities of 444 and103 m A h g^(-1) at the current densities of 0.1 and 3 A g^(-1) , respectively, obvious higher than the corresponding values of the bare sample, 371 and 60 mA h g^(-1) . Moreover, the composite anode maintains a discharge capacity of 306 mA h g^(-1) after 500 cycles at 1 A g^(-1) , suggesting an excellent cycle stability. It is believed that the nitrogen-doped amorphous carbon layer has provided additional lithium storage capacity and stabilized the structure integrity of mesocarbon microbeads. This work demonstrates that the capacity and rate performance of commercial graphitic carbons can be much improved by simply introducing a nitrogen-doped carbon coating layer active for Li storage, making them attractive for high power Li-ion batteries.

关键词： Li-ion batteries MCMBs Anode Carbon coating Rate capability

On the fouling mechanism of polysulfone ultrafiltration membrane in the treatment of coal gasification wastewater

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Frontiers of Chemical Science and Engineering 2016年第4期10卷 490-498页

作者： Xue zou Jin Li School of Civil Engineering Beijing Jiaotong University Beijing 100044 China College of Architectural Engineering North China University of Technology Beijing 100144 China

Membrane fouling has been investigated by using a polysulfone ultrafiltration membrane with the molecular weight cutoff of 20 kDa to treat crushed coal pressurized gasification wastewater. Under the conditions of different feed pressures, the permeate flux declines and rejection coefficients of pollutants referring to three parameters （total organic carbon （TOC）, chroma and turbidity） were studied. The membrane fouling mechanism was simulated with three classical membrane fouling models. The membrane image and pollutants were analyzed by scanning electron microscopy and gas chromatography-mass spectrography （GC-MS）. The results indicate that the permeate flux decreases with volume reduction factor before reaching a constant value. The rejection coefficients were also measured： fTOC = 70.5%,fc = 84.9% andfa- = 91%. Further analysis shows that the higher the feed pressure is, the sooner the permeate flux reaches constant value and the more sharply the permeate flux declines. Constant flux indicates a nonlinear growth with feed pressure （PF）： when Pr equals 1.2 bar, the mark for the critical flux, slight membrane fouling occurs; when PF exceeds 1.2 bar, cake layer pollution aggravates. Also the rejection coefficients of global pollutant increases slightly with PF, suggesting the possibility of cake compression when PF exceeds 1.2 bar. Through regression analysis, the fouling of polysulfone ultrafiltration membrane could be fitted very well by cake filtration model. The membrane pollutants were identified as phthalate esters and long-chain alkenes by GC-MS, and a certain amount of inorganic pollutants by X-ray photoelectron spectroscopy.

关键词： membrane fouling ultrafiltration membrane,coal gasification wastewater rejection coefficient

The “twinkling star” materials: highly superior molecular switches for bioimaging

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Science China Chemistry 2019年第6期62卷 657-658页

作者： Qi zou Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power Shanghai University of Electric Power

Artificial molecular switches have been the robust tools for diverse fields of modern science and technology, including molecular machines, smart materials, and bioimaging [1]. The development of new concepts to enable the creation of efficient molecular switches has been a longstanding activity in these fields. Up to date, various kinds of molecular switches have been developed, most of which work between two or more stable states, and the rest of them requires at least an additional energy or chemical stimuli.

关键词： molecular development states

Discussion on the geometric factor in the detection of high energy electrons in geospace

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Science China(Technological Sciences) 2008年第1期51卷 1-9页

作者： CHEN HongFei SHI WeiHong zou Hong zou JiQing Institute of Space Physics and Applied Technology School of Earth and Space SciencesPeking UniversityBeijing 100871China

High energy electron is a kind of sources to be detected in the geospace environ- ment. Generally, the particle telescope with much thick semiconductor detector is used as the sensor for energetic electrons because they can penetrate deeply into the detector. The more energy of the electrons is, the deeper they can penetrate into, so that the geometric factor varies with energy of the incident electrons. We discuss the geometric factor of particle radiation detector (PRD), which is a payload on ZY-1 (CBERS-1 and CBERS-2) satellites to monitor the high energy particle ra- diation inside the satellites. According to the NASA’s AE8 model, the geometric factors of electrons for the low energy bin (0.5―1.0 MeV) and the high energy bin (> 2.0 MeV) are 2.468 and 1.736 cm2·sr, respectively. These results are much differ- ent from the traditional calculation of the geometric factor that is 1.18 cm2·sr. The angle-response function of the telescope is also derived, which can be useful for design of the telescope and analysis of the directional distribution.

关键词： geometric factor high energy electrons particle radiation space exploration

Solidification segregation behavior of Nb-containing 310S steel

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Journal of Iron and Steel Research International 2023年第1期30卷 82-87页

作者： Yu-tuo Zhang Hao zou School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159LiaoningChina Institute of Metal Research Chinese Academy of SciencesShenyang 110016LiaoningChina

The solidification characteristics and segregation behavior of solute elements Nb,Ni,Mn,Si,Cr and C in 0.3 wt.%Nb-310S steel were investigated using the isothermal solidification quenching experiment and Thermo-Calc *** phase transformation for 0.3%Nb-310S steel under equilibrium condition can be summarized as follows:liquid(L)→L+γ(1406℃)→γ(1334℃)→γ+NbC(1322℃)→γ+NbC+M_(23)C_(6)(1006℃)→γ+NbC+M_(23)C_(6)→σ(755℃).The results showed that the solidification began with the formation of primary austenite *** volume fraction of the liquid phase decreased rapidly as the temperature decreased in the initial solidification stage,and then,the liquid phase fraction decreased *** austenite formed,Mn and Ni were enriched in the solid phase,while Nb and C were rejected into the *** was present the highest segregation coefficient in 0.3%Nb-310S austenitic stainless *** segregation of Nb was the most serious,followed by Mn,Ni and *** and Si exhibited slight segregation during the *** solidification was terminated by the formation of NbC phase.

关键词： 310S steel Nb Solidification Segregation Thermo-Calc calculation

Research on polarization of oil spill and detection

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Acta Oceanologica Sinica 2016年第3期35卷 84-89页

作者： CAI Yang zou Yarong LIANG Chao zou Bin South China Sea Forecast Center State Oceanic Administration Guangzhou 510310 China National Satellite Ocean Application Services Beijing 100081 China Key Laboratory of Space Ocean Remote Sensing and Application State Oceamic Administration Beijing 100081 China

The SAR（Synthetic Aperture Radar） has the capabilities for all-weather day and night use. In the case of determining the effects of oil spill dumping, the oil spills areas are shown as dark spots in the SAR ***, using SAR data to detect oil spills is becoming progressively popular in operational monitoring, which is useful for oceanic environmental protection and hazard reduction. Research has been conducted on the polarization decomposition and scattering characteristics of oil spills from a scattering matrix using allpolarization of the SAR data, calculation of the polarization parameters, and utilization of the CPD（Co-polarized Phase Difference） of the oil and the sea, in order to extract the oil spill information. This method proves to be effective by combining polarization parameters with the characteristics of oil spill. The results show that when using Bragg, the oil spill backscattering machine with Enopy and a mean scatter α parameter. The oil spill can be successfully identified. However, the parameter mechanism of the oil spill remains unclear. The use of CPD can easily extract oil spill information from the ocean, and the polarization research provides a base for oil spill remote sensing detection.

关键词： oil spill polarization detection SAR