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FUZZY MODEL FOR TWO-DIMENSIONAL RIVER WATER QUALITY SIMULATION UNDER SUDDEN POLLUTANTS DISCHARGED

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Journal of Hydrodynamics 2007年第4期19卷 434-441页

作者： LI Ru-zhong SHIGEKI Masunaga HONG Tian-qiu QIAN Jia-zhong school of resources and {2.al Engineering Hefei University of Technology Hefei 230009 China Graduate school of environment and Information Sciences Yokohama National University Yokohama 240-8501 Japan

Based on the fuzziness and impreciseness of water environmental system, the fuzzy arithmetic was used to simulate the fuzzy and imprecise relations in modeling river water quality. By defining the parameters of water quality model as symmetrical triangular fuzzy numbers, a two-dimensional fuzzy water quality model for sudden pollutant discharge is established. From the fuzzy model, the pollutant concentrations, corresponding to the specified confidence level of a, can be obtained by means of the a-cut technique and arithmetic operations of triangular fuzzy numbers. Study results reveal that it is feasible in theory and reliable on calculation applying triangular fuzzy numbers to the simulation of river water quality.

关键词： fuzzy water quality simulation model triangular fuzzy number membership function a-cut technique

Formation Mechanism and Exhumation Processes for HP-UHP Metamorphic Rocks in Dabie Mountains

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Journal of china university of Geosciences 2004年第2期15卷 193-205页

作者： Hou Mingjin Tectonique et Bassins Sédimentaires Laboratoire, Université de Paris-Sud 91405, ORSAY Cedex, France school of resources and {2., hefei university of technology, hefei 230009, china anhui Geological Survey, hefei 2.0001, china Tang Jiafu anhui Geological Survey, hefei 2.0001, china Tectonique et Bassins Sédimentaires Laboratoire Université de Paris-Sud 91405ORSAY CedexFrance school of resources and {2. Hefei University of TechnologyHefei 230009China anhui Geological Survey Hefei 230001China anhui Geological Survey Hefei 230001China

The high, ultrahigh pressure metamorphic rocks, widely distributed in Dabie Mountains, were described in terms of the geological setting, the marks of the petrology and the mineralogy of the ultrahigh pressure (UHP) metamorphic rocks. According to the estimated uplifting and denudation of the Dabie Mountains, and to the thermodynamics theory, were assessed the depth and pressure (high pressure autoclave) of the formation setting of the UHP metamorphic rocks. Based on all the information mentioned above, a new explanation is derived from the mechanism of formation and the processes of exhumation of the UHP metamorphic rocks.

关键词： blueschist belt coesite-bearing eclogite belt abnormal crustal pressure,high pressure autoclave

Wear Performance of Laser Surface Hardened GCr15 Steel

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Journal of Wuhan university of technology(Materials Science) 2010年第1期25卷 84-88页

作者：雷声 school of Materials Science and Engineering Hefei University of Technology Department of Electromechanical Engineering Anhui Institute of Architecture and Industry

In order to assess the new tribological properties of laser surface hardened GCr15 steel, the wear resistance between specimens treated with laser and those of conventionally hardened under dry sliding conditions was compared. The change of wear mechanisms in laser hardened GCr15 resulted in a distinct difference in wear rates. The results showed that quenched zones not only had sufficient depth of hardening and higher hardness, but had more retained austenite and finer carbides because of a higher degree of carbide dissolution. Laser surface hardened GCr15 steel specimens exhibited superior wear resistance to their conventionally hardened specimens due to the effects of the microstructure hardening, high hardness and toughness. The wear mechanism for both the laser quenched layer and conventionally hardened layer was highly similar, generally involving adhesive, material transfer, wear-induced oxidation and plowing. When conventionally hardened block specimens rubbed against the laser hardened specimens, the surface of conventionally hardened block specimens was polished. The microstructural thermal stability was increased after laser surface treatment.

关键词： laser hardening dry sliding conditions GCr15 steel wear mechanisms

Fast parallel algorithms for discrete Gabor expansion and transform based on multirate filtering

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Science china(Information Sciences) 2012年第2期55卷 293-300页

作者： TAO Liang1 & GU JuanJuan2.1school of Computer Science and technology,{2. university,hefei 2.0039,china 2.epartment of Electronic Information and Electrical Engineering,hefei university,hefei 2.002.,china school of Computer Science and technology Anhui University Hefei China Department of Electronic Information and Electrical Engineering Hefei University Hefei China

The Gabor transform has long been recognized as a very useful tool for the joint time and frequency analysis in signal *** real time applications,however,were limited due to the high computational complexity of the Gabor transform *** this paper,some novel and fast parallel algorithms for the finite discrete Gabor expansion and transform are presented based on multirate *** analysis filter bank is designed for the finite discrete Gabor transform(DGT)and a synthesis filter bank is designed for the finite discrete Gabor expansion(DGE).Each of the parallel channels in the two filter banks has a unified structure and can apply the FFT and the IFFT to reduce its computational *** computational complexity of each parallel channel does not change as the oversampling rate *** fact,it is very low and depends only on the length of the input discrete signal and the number of the Gabor frequency sampling *** computational complexity of the proposed parallel algorithms is analyzed and compared with that of the major existing parallel algorithms for the finite DGT and *** results indicate that the proposed parallel algorithms for the finite DGT and DGE based on multirate filtering are very attractive for real time signal processing.

关键词： discrete Gabor expansion discrete Gabor transform critical sampling and oversampling multirate filtering analysis and synthesis filter banks

Bell violation for the thermal states of an XXZ spin chain with Dzialoshiski-Moriya interaction

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2074-2079页

作者： MA XiaoSan 1 & WANG AnMin 2.1 school of Electric Engineering and Information,anhui {2. of technology,Maanshan 2.3002.china 2.Department of Modern Physics,{2. of Science and technology of china,hefei 2.002.,china school of Electric Engineering and Information Anhui University of Technology Maanshan China Department of Modern Physics University of Science and Technology of China Hefei China

The effect of Dzialoshiski-Moriya (DM) interaction on the violation of Bell inequality for thermal states of interacting qubits via a two-qubit XXZ spin chain is *** results imply that the DM interaction and anisotropy taking a large positive value can enhance the Bell violation and improve the threshold temperatures of *** the comparison between the Bell violation and thermal entanglement,we find that the threshold temperatures of thermal entanglement are higher than those of the Bell *** implies that some states are entangled but the Bell inequality is not violated.

关键词： Bell violation threshold temperatures DM interaction

EXPERIMENTAL STUDY OF THE NON-DARCY FLOW AND SOLUTE TRANSPORT IN A CHANNELED SINGLE FRACTURE

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Journal of Hydrodynamics 2011年第6期23卷 745-751页

作者： CHEN Zhou QIAN Jia-zhong QIN Hua school of resources and {2.al Engineering Hefei University of Technology Hefei 230009 China

The characterization of fracture rocks is always a key issue in understanding the flow and solute transport in fractured media. This article studies the solute transport in a Channeled Single Fracture （CSF）, a single fracture with contact in certain areas. The flow in a CSF often has preferential pathways and the transport in a CSF often has Break Through Curves （BTCs） with long tails. The Surface Contact Ratio （SCR）, the ratio of the contact area to the total fracture area, is an important indicator for the fracture surface roughness. To study the flow and solute transport in a CSF, a controlled physical model is constructed and a series of flow and tracer test experiments are carried out. Under our experimental conditions, the flow in a CSF is found to follow the Forchheimer equation , where and are the hydraulic gradient and the average pore velocity, respectively and and are two parameters related to the viscous and inertial flow components, respectively. Furthermore, it is found that b decreases with the decrease of SCR. For the solute transport, it is found that the BTCs often deviate from the traditional Fickian behavior, by the early-arrival and the long tailing. More interestingly, the observed BTCs often have a double-peak or a multi-peak, that would be difficult to explain using the existing transport theory such as the Advection-Dispersion Equation （ADE）. In addition, the longitudinal dispersion coefficient is found to be scale-dependent in a CSF and the relationship is of exponential type.

关键词： channeled single fracture surface contact ratio non-Darcian non-Fickian

TLR3 Ligand-Induced Accumulation of Activated Splenic natural Killer Cells into Liver

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Cellular & Molecular Immunology 2005年第6期2卷 449-453页

作者： Jing Wang~1 Jiawei Xu~1 Weici Zhang~1 Haiming Wei~1 Zhigang Tian~(1,2. ~1Institute of Immunology,school of Life Sciences,university of Science and {2. of china,hefei,anhui,china ~2.nstitute of Immunology,school of Life Sciences,university of Science and {2. of china,443 Huangshan Road,hefei 2.002.,anhui,china. Institute of Immunology School of Life Sciences University of Science and Technology of China Hefei Anhui China

It has been revealed that poly I：C is a potent stimulator for NK cells, which can induce NK cell rapid activation and preferential accumulation into liver. However, the process mediating the influx of NK cells remains obscure. In this study, we found that poly I：C administration increased the portion and absolute number of NK cells in liver, but largely decreased those in spleen. There were no obvious changes of these lymphocytes in other immune organs. The results from splenic adoptive transfer and splenectomy showed that the recruited spleen NK cells contributed to the accumulation of NK cells in liver, and this process was regulated by the production of chemokines and the presence of T cells. This investigation will help to understand the enhanced immune cell recruitment in liver upon viral infection. Cellular ＆ Molecular Immunology. 2.05;2.6）：449-453.

关键词： liver spleen NK poly I:C recruitment

Asymptotic profile of solutions to the two-dimensional dissipative quasi-geostrophic equation

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Science china Mathematics 2010年第10期53卷 2733-2748页

作者： DONG BoQing & LIU QingQing school of Mathematical Sciences,anhui {2.,hefei 2.0039,china school of Mathematical Sciences Anhui University Hefei China

This paper is concerned with the asymptotic behavior of the two-dimensional dissipative quasigeostrophic *** on the spectral decomposition of the Laplacian operator and iterative techniques,we obtain improved L2.decay rates of weak solutions and derive more explicit upper bounds of higher order derivatives of *** also prove the asymptotic stability of the subcritical quasi-geostrophic equation under large initial and external perturbations.

关键词： quasi-geostrophic equation L2 decay asymptotic stability

Dynamic behavior of micro-diaphragms and its characterized description

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Science china(Physics,Mechanics & Astronomy) 2009年第8期52卷 1345-1356页

作者： GE LiFeng school of Electronic Science and technology, {2. university, hefei 2.0039, china school of Electronic Science and technology Anhui University Hefei China

Diaphragm structures with micron scale play a significant role in microtransducers and micro-nano devices, and the performance of these devices depends mainly on the dynamic behaviour of diaphragms. Micro-diaphragms are treated commonly as membranes and in some cases as plates or plates in tension (called TD plates for short), but they also show in many cases the behaviour of plates in tension and supported by air spring (called TDK plates for short). Therefore, it is necessary to perform systematic research on the dynamic behaviour of micro-diaphragms, and establish a characterized mathematical description. This paper focuses on the TDK plates since they possess universality, gives the corresponding basic equations, and then derives analytical solutions of TDK circular plates under clamped and simply supported boundary conditions. This paper also gives a 3D plot representation of characteristic curved surfaces, revealing the transition from the TDK and TD plate to the pure plate or pure membrane behaviour; and further uses the value φ to determine the property of diaphragms. Its two extreme cases, i.e. φ = 0 and φ = ∞ , correspond to pure plate or pure membrane, respectively. Thus, membrane, plate and TD plate can be treated as special cases of TDK plate. In addition, this paper reveals that the presence of air-spring not only enhances the restoring force of diaphragm such that increases its natural frequencies, but also results in the resonance of a dynamic system consisting of diaphragm and air-spring. These analytical and computational results are significant for the understanding of the operation mechanism of capacitive microtransducers and their optimized design.

关键词： micro-diaphragm membrane and plate TD plate and TDK plate dynamic behaviour characterized description