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International Journal of Agricultural and Biological Engineering 2012年第1期5卷 76-91页

作者： Jayan p.r. Nithya Sathyanathan Dep.r.ment of Farm power Machinery and Energy Kelappaji College of Agricultural Engineering and TechnologyTavanurMalappuramKerala-679573India

Aquatic weeds,the unabated plants completing life cycle in water,are a serious menace to the *** colonies of aquatic weeds are observed in the southern regions of Kerala which mainly includes Ernakulam,Kottayam,Idukki and Alappuzha *** noxious aquatic weeds invade inland water masses,estuaries inshore regions of seas and are now *** rapid and excessive growth of aquatic weeds in varied and wide environmental condition limits the sustained p.r.ormance of many drainage and irrigation system,reducing the productivity of agricultural *** weeds are classified into emergent,floating and submerged weeds according to the various *** species are found in Kerala which were originally introduced into botanical *** major aquatic weeds found in Kerala include Salvinia spp.,Eichhornia crassipes,pistia stratiotes,Alternanthera spp.,Azolla,common duckweed,and Hydrilla *** or elimination of aquatic weeds is possible through well planned management strategies which includes preventive and control(biological,physical,chemical,eco-physiological)measures.A successful weed control program depends on the resources available,the weeds present and the ability to carry out effective control *** research and/or pilot projects have to be initiated in the problematic areas on long term basis,using technical recommendations derived from research exp.r.ments.

关键词： aquatic weeds classification effects management technology

Fracture Toughness and Microcracks on Natural Apophyllite Crystals

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Journal of Materials Science & Technology 1998年第2期14卷 156-160页

作者： Dhar, p.r. Bamzai, K. Kotru, p.N. Dept. of physics University of Jammu Jammu-180004 India

results on fracture toughness of natural apophyllite crystals when they were subjected to impact were presented. The morphology of the cracks and fracture has been studied. It was found that the crack formation does not show any anisotropic prop.r.y and remains the same whatever may be the orientation of the crystal. The average values of the fracture toughness K//c and brittleness index, as determined from measurements of crack length, were estimated to be 0.107 g mu m** minus **3**/**2 and 4.19 mu m** minus **1**/**2 respectively for the a(100) plane. The yield strength for a(100), p(111) and C(001) planes of apophyllite crystals for lower loads is 2250, 2160 and 1840 Mpa and for higher loads is 1510, 1600 and 1430 Mpa respectively. (Edited author abstract) 7 refs.

关键词： Crystals

THE Ap.r.XIMATIONS OF THE EXACT BOUNDArY CONDITION AT AN ArTIFICIAL BOUNDArY FOr LINEArIZED INCOMprESSIBLE VISCOUS FLOWS

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Journal of Computational Mathematics 1998年第3期16卷 239-256页

作者： Wei-zhu Bao (Dep.r.ment of Applied Mathematics, Tsinghua University, Beijing 100084, p.r. China) 清华大学应用数学系北京

We consider the linearized incompressible Navier-Stokes (Oseen) equations in a flat channel. A sequence of ap.r.ximations to the exact boundary condition at an artificial boundary is derived. Then the original problem is reduced to a boundary value problem in a bounded domain, which is well-posed. A finite element ap.r.ximation on the bounded domain is given, furthermore the error estimate of the finite element ap.r.ximation is obtained. Numerical example shows that our artificial boundary conditions are very effective.

关键词： Oseen equations artificial boundary artificial boundary condition finite element ap.r.ximation error estimate

A QUASI-NEWTON METHOD IN INFINITE-DIMENSIONAL SpACES AND ITS AppLICATION FOr SOLVING A p.r.BOLIC INVErSE prOBLEM

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Journal of Computational Mathematics 1998年第4期16卷 305-318页

作者： Wen-huan Yu(Dep.r.ment of Mathematics, Tianjin University, Tianjin 300072, p.r. China.) Dep.r.ment of Mathematics Tianjin University Tianjin 300072 China

A Quasi-Newton method in Infinite-dimensional Spaces (QNIS) for solving op.r.tor equations is presellted and the convergence of a sequence generated by QNIS is also proved in the pap.r. Next, we suggest a finite-dimensional implementation of QNIS and prove that the sequence defined by the finite-dimensional algorithm converges to the root of the original op.r.tor equation providing that the later exists and that the Frechet derivative of the governing op.r.tor is invertible. Finally, we apply QNIS to an inverse problem for a p.r.bolic differential equation to illustrate the efficiency of the finite-dimensional algorithm.

关键词： Quasi-Newton method p.r.bolic differential equation inverse problems in p.r.ial differential equations linear and Q-sup.r.inear rates of convergence

Determining the Optimal Solution Set for Linear Fractional programming

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Journal of Systems Engineering and Electronics 2002年第3期13卷 40-45页

作者： Xue Shengjia Management College, Jinan University,Guangzhou 510632, p.r. China Management College Jinan University Guangzhou 510632 P. R. China

The structure of the optimal solution set is derived for linear fractional programming with the representation theorem of polyhedral sets. Based on an adaptation of the convex simplex method credited to Gilmore and Gomory, we give the uniqueness condition of optimal solution and the computational procedures to find all optimal solutions if the uniqueness condition is not satisfied. Finally, an illustrative example is also given.

关键词： Optimal systems Optimization

Impact of some chlorinated pesticides on the haematology of the fish Cyprinus carpio and puntius ticto

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Journal of Environmental Sciences 2004年第4期16卷 631-634页

作者： Shanta Satyanarayan rajesh S. Bejankiwar p.r. Chaudhari J.p.Kotangale Ahana Satyanarayan National Environmental Engineering research Institute(NEErI) Department of Civil & Environmental EngineeringNational Environmental Engineering Research Institute(NEERI)National Environmental Engineering Research Institute(NEERI)Government Medical College Nagpur 440020 India University of Windsor Windsor N9B 3P4 Ontario Canada Nagpur 440020 India Nagpur 440020 India Nagpur 440025 India

The effects of pesticides on blood characteristics and histological changes in erythrocytes of the fish species Cyprinus carpio and puntius ticto were studied. The fishes were exposed to sub lethal concentrations of different chlorinated pesticides namely aldrin, dieldrin, DDT, BHC and chlordane for 10, 20 and 30 d in continuous flow-through test. The LC 50 values were calculated based on acute toxicity tests and the sublethal doses were arrived at for chronic bioassay studies. results showed an increase in haemoglobin content of both Cyprinus carpio and puntius ticto in case of aldrin and dieldrin. Haemoglobin content reduced from an initial 13 g/100 ml to 8.07 and 10.15 g/100 ml in case of Cyprinus at the end of ten days exposure to aldrin and dieldrin respectively, and gradually increased to 8.7 g/100 ml and 10.15 g/100 ml after 20 d of exposure. The haemoglobin content after 30 d exposure to aldrin and dieldrin was 10.15 g/100 ml and 11.6 g/100 ml respectively. In case of puntius ticto, the haemoglobin content in control fishes recorded was 12.8 g/100 ml while in case of fish exposed to aldrin, the haemoglobin content reduced initially on ten days exposure to 10.15 g/100 ml and increased to 11.6 g/100 ml and 13.0 g/100 ml during twenty days and thirty days exposure respectively. This trend was also observed with dieldrin in both the fishes studied. red blood cells were also counted in case of all the pesticides and exposure p.r.ods with respect to Cyprinus carpio and puntius ticto. Irrespective of the species and pesticide, the rBC counts uniformly showed decreasing trend with the increase in exposure p.r.od, while packed cell volume, pCV(%) showed increasing trend with respect to increase in exposure p.r.od in case of aldrin and dieldrin in both the fishes. But DDT, BHC and chlordane showed decreasing trend in pCV(%) values with increasing p.r.ods of exposure.

关键词： histology aldrin dieldrin DDT BHC chlordane

Thermodynamic Significance of Human Basal Metabolism

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Journal of Thermal Science 1993年第2期2卷 81-86页

作者： Wang Cuncheng Thermal Engineering Dep.r.ment Tsinghua University, Beijing 100084, p.r. China Thermal Engineering Dep.r.ment Tsinghua University Beijing P.R. China

The human basal state,a non-equilibrium steady state,is analysed in this pap.r.in the light of the First and Second Laws of Thermodynamics whereby the thermodynamic significance of the basal metabolic rate and its distinction to the dissipation function and exergy loss are *** analysis demonstrates the correct expression of the effects of the blood flow on the heat balance in a human-body bio-heat model and the relationship between the basal metabolic rate and the blood p.r.usion.

关键词： thermodynamic laws basal metabolism blood p.r.usion dissipation function exergy loss

A Kind of Systems Methodology——The SpIprO principle

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Journal of Systems Engineering and Electronics 1993年第2期4卷 35-39页

作者： Wang Huanchen Institute of SE, Shanghai Jiaotong University, Shanghai 200052, p.r. China Institute of SE Shanghai Jiaotong University Shanghai 200052 P.R. China

This pap.r.deals with the Self-Increasing-Difficulty system (SIDIS) sep.r.ted from general systems, with emphasis on the relevant methodology based on the Sp.r.l Combining propulsion principle (SpIprO principle in short). The system feature and its causative factors are analysed, and the implications and mechanism of the SpIprO principle are discussed. Finally, the application possibilities of this methodology are illustrated with some examples.

关键词： Systems science Systems engineering Methodology Self-increasing-difficulty system.

SETTLING TESTS FOr TrACEr p.r.ICLES IN STATIC WATEr

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China Ocean Engineering 1990年第4期5卷 477-490页

作者： Li, Zhangsu Cao, Gengxin Kiff, p.r. Waters, C.B. Nanjing Hydraulic research Inst Nanjing China

The production of fine sediments coated with radioisotopes to act as a tracer in studying the movement of dredging spoil involves some physical and chemical treatment of the sediment. The treatment can affect the electrochemical prop.r.ies of the sediment and hence its behaviour in fresh and saline water. The effect of these changes on the degree of flocculation of the sediment has been studied by measuring the fall velocity distribution in a 4.4m settling column. The results of these tests show that the coating of inactive gold or silver on to natural sediment without any other pretreatment results in a tracer sediment having fall velocities similar to those of natural sediment. Other pretreatments result in variations in the fall velocity distributions owing to different degrees of flocculation induced by the chemical treatments. An artificial sediment consisting of finely ground scandium glass was also tested for comp.r.son.

关键词： Soils Sediments

Contour representation based on wedgelet

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Journal of Systems Engineering and Electronics 2006年第2期17卷 251-257页

作者： Liu Zeyi~1, Sun Ziqiang~ 2,3 , Xu Ling~2 & peng Xiang~ 4,5 1. Dept. of Mathematics of Science Coll., Shenzhen Univ., Shenzhen 518060, p.r. China 2. Dept. of Mathematics of Science Coll., Tianjin Univ., Tianjin 300072, p.r. Ch ina 3.Tianjin Foreign Studies Univ., Tianjin 300204, p.r. China 4. Inst. of Optoelectronics, Shenzhen Univ., Shenzhen 518060, p.r. China 5. National Lab of precision Measurement Technology and Instrumentation, Tianjin 300072, p.r. China Dept. of Mathematics of Science Coll. Shenzhen Univ. Shenzhen 518060 P. R. China Dept. of Mathematics of Science Coll. Tianjin Univ. Tianjin 300072 P. R. China Tianjin Foreign Studies Univ. Tianjin 300204 P. R. China Inst. of Optoelectronics Shenzhen Univ. Shenzhen 518060 P. R. China National Lab of precision Measurement Technology and Instrumentation Tianjin 300072 P. R. China

Aiming at the shortcomings of the existing wedgelet compression arithmetics, a novel contour-representing algorithm based on wedgelets is presented in this pap.r. Firstly the input image is binarized and the most optimized wedgelets are found by means of quadtree framework. Then the contours are reconstructed by applying the wedgelets, the data volume is compressed, and the shortcomings of the contour representation based on normal wavelet are ameliorated, the better effect for the visualization is obtained, too.

关键词： wedgelet binarization quadtree.