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Chinese Physics B 2012年第4期21卷 586-596页

作者： P.Balasubramaniam M.Kalpana r.rakkiyappan Department of Mathematics Gandhigram Rural Institute-Deemed UniversityGandhigram-624302TamilnaduIndia Department of Mathematics Bharathiar UniversityCoimbatore-641046TamilnaduIndia

Fuzzy cellular neural networks （FCNNs） are special kinds of cellular neural networks （CNNs）. Each cell in an FCNN contains fuzzy operating abilities. The entire network is governed by cellular computing laws. The design of FCNNs is based on fuzzy local rules. In this paper, a linear matrix inequality （LMI） approach for synchronization control of FCNNs with mixed delays is investigated. Mixed delays include discrete time-varying delays and unbounded distributed delays. A dynamic control scheme is proposed to achieve the synchronization between a drive network and a response network. By constructing the Lyapunov-Krasovskii functional which contains a triple-integral term and the free-weighting matrices method an improved delay-dependent stability criterion is derived in terms of LMIs. The controller can be easily obtained by solving the derived LMIs. A numerical example and its simulations are presented to illustrate the effectiveness of the proposed method.

关键词： asymptotic stability chaos fuzzy cellular neural networks linear matrix inequalities synchronization

Climate change and preservation of minority languages in the upper regions of Ghana:A systematic review

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Chinese Journal of Population,resources and Environment 2022年第2期20卷 177-189页

作者： michael Addaney Stella Afi Makafui Yegblemenawo Jonas Ayaribilla Akudugu Mavis Antiri Kodua Department of Planning and Sustainability of University of Energy and Natural resources SunyaniGhana Department of Language and Communication Sciences of the Kwame Nkrumah University of Science and Technology KumasiGhana

A well-recognized fact is that addressing the impacts of climate change on vulnerable communities and minority groups remains a central focus toward achieving the Sustainable Development Goals,specifically Goals 11 and *** for effective adaptation to climate change through national and local efforts fundamentally aim to create environmentally sustainable,socially inclusive,and economically vibrant *** paper associates the impacts of climate change to the preservation of threatened minority languages in semi-arid areas in Northern *** review relies on primary and secondary sources on climate-induced migration,minority languages,and threats of language loss through a keyword search followed by rigorous content *** study confirms that forced displacement due to harsh climatic and other environmental conditions is currently occurring in the upper regions(Upper East and Upper West regions)of Ghana with minority linguistic groups being forced to migrate to the southern part of the country,where their culture and language are threatened due to large linguistic *** literature well establishes the north-south mobility with various debates on its root ***,the phenomenon is understudied along with the lack of specific national strategies for addressing it and the associated language ***,the need emerges for further studies to enhance the current understanding of the phenomenon to inform policy interventions and protect minority languages threatened by climate-induced *** focus on an understudied subject and geographic scope makes the findings extremely relevant for the expansion of knowledge on internal migration in the context of climate change in Northern Ghana.

关键词： Climate changecondition Climate migration Minority languages Semi-arid Ghana Threatened languages

Trace Elements and Sr, Nd Isotope Geochemistry of the Lajimiao Norite-Gabbro from the North Qinling Belt

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Acta Geologica Sinica(English Edition) 1994年第2期68卷 137-151页

作者： S.r.Hart Department of Geology and Geopphysics Woods Hole Oceanographic InstituteWoods

The Lajimiao norite-gabbro complex, as a part of the ophiolites on the southern side of the North Qinling belt, consists of gabbro and norite-gabbro. They were derived from different magma series: the gabbro was derived from tholeiitic magma series with higher TiO2, rEE abundance and Fe3+/Fe2+ ratio ; norite-gabbro was derived from calc-alkali magma series with lower TiO2, Fe3+/Fe2+ ratio and rEE abundance and much lower HrEE abundance, which suggests that the source of the norite-gabbro magma was deeper and controlled by eclogite facies. Geochemical characteristics of both plutonic rocks are similar to those of island-arc basalts, such as relatively high contents of Ba, Pb and Sr and relatively low contents of Nb, Zr and N *** Sr, Nd isotopic characteristics of the Lajimiao norite-gabbro complex are similar to those of ophiolites. Its εNd values are constant, about+2; whereas εst values have wide variation from - 6.4 to +31.2 and positively correlate with Na2O, H2O+ and CO2 contents and the Fe3+/Fe2+ ratio. The εNd- Nd/Th, εNd- La/Nb and εNd-Ba/Nb diagrams clearly show that there were significant components of terrigenous sediments in the mantle source of the Lajimiao norite-gabbro complex. It suggests that large amount of sediments had been carried into the mantle by the subducted ancient Qinling sea plate during the Palaeozoic.

关键词： trace element Sr/Nd isotopes norite-gabbro Lajimiao North Qinling

PArTIAL FErrErS MATrICES

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Applied Mathematics(A Journal of Chinese Universities) 1994年第3期9卷 279-289页

作者： r．A．Brualdi 李乔 1. Department of Mathematics University of Wisconsin 53706 Madison Wisconsin U.S.A. 2. Department of Mathematics University of Science and Technology of China 230026 Hefei

We introduce a class of n×n matrices of 0's and l's which can be regarded as generalizations of the classical Ferrets boards of rook theory. Assuming the matrices are fully indecomposable, we determine the minimum permanent and the minimum numberof l's as a function of n. We also characterize these matrices in terms of weighted,top-rooted trees.

关键词： Ferrers board fully indecomposable matrix permanent.

Effect of Process Parameters on Tensile Strength of Friction Stir Welded Cast LM6 Aluminium Alloy Joints

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Journal of Materials Science & Technology 2009年第5期25卷 655-664页

作者： M.Jayaraman r.Sivasubramanian V.Balasubramanian Department of Mechatronics Engineering Kongu Engineering CollegeErodeTamil NaduIndia Department of Mechanical Engineering Coimbatore Institute of TechnologyCoimbatoreTamil NaduIndia Centre for Materials Joining&research(CEMAJOr) Department of Manufacturing EngineeringAnnamalai UniversityAnnamalainagarTamil NaduIndia

This paper reports the effect of friction stir welding （FSW） process parameters on tensile strength of cast LM6 aluminium alloy. Joints were made by using different combinations of tool rotation speed, welding speed and axial force each at four levels. The quality of weld zone was investigated using macrostructure and microstructure analysis. Tensile strength of the joints were evaluated and correlated with the weld zone hardness and microstructure. The joint fabricated using a rotational speed of 900 r/min, a welding speed of 75 mm/min and an axial force of 3 kN showed superior tensile strength compared with other joints. The tensile strength and microhardness of the welded joints for the optimum conditions were 166 MPa and 64.8 Hv respectively.

关键词： LM6 aluminium alloy Friction stir welding Tool rotation speed Welding speed Axial force Tensile strength