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Current Zoology 2011年第4期57卷 419-420,421-428页

作者： Michael J. BERAN Julie s. JOHNsON-PYNN Christopher READY Language Research Center Georgia State University Atlanta GA 30302 USA Department of Psychology Berry College Mount Berry GA 30149 USA

We presented a quantity judgment task that involved comparing two sequentially presented sets of items to preschoolers and chimpanzees using nearly identical procedures that excluded verbal instructions to children. Trial difficulty in this task reflected the ratio difference between sets of discrete items where larger ratios （e.g., 0.80 as from comparing 4 to 5） were more difficult than smaller ones （e.g., 0.50 as from comparing 4 to 8）. Children also completed verbal-based tasks probing the relationskip between counting proficiency and performance on the quantity judgment task of sequentially presented identical sized items. Both species＇ performance was best when ratios between comparison sets were small regardless of set size in all types of tasks. Generally, chimpanzees and older children performed better than younger children except at larger ratios. Children＇s counting proficiency was not related to success in choosing the larger of two quantities of identical-sized items. These results indicate that chimpanzees and children share an approximate number sense that is reflected through analog magnitude estimation when comparing quantities [Current Zoology 57 （4）： 419-428, 2011].

关键词： Numerical cognition Quantity judgments Children Chimpanzees Pan troglodytes

Electrochemical process of titanium extraction

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中国有色金属学会会刊：英文版 2007年第2期17卷 429-433页

作者： CH. RVs. NAGEsH C. s. RAMACHANDRAN Defence Metallurgical Research Laboratory HyderabadA.P. India-500058

A wide variety of processes are being pursued by researchers for cost effective extraction of titanium metal. Electrochemical processes are promising due to simplicity and being less capital intensive. some of the promising electrochemical processes of titanium extraction were reviewed and the results of laboratory scale experiments on electrochemical reduction of TiO2 granules were brought out. some of the kinetic parameters of the reduction process were discussed while presenting the quality improvements achieved in the experimentation.

关键词：钛萃取电化学还原过程动力学参数

The Trend of Homicides in south Kerala from 2002-2016:A Retrospective Forensic Autopsy-Based study

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Journal of Forensic science and Medicine 2021年第4期7卷 111-116页

作者： Nikhil Dileeph s.sharija Antony stanley K.Valsala s.s.sujisha Nikita Prabhakaran Department of Forensic Medicine De SMCSI Medical CollegeThiruvananthapuramKeralaIndia Department of Forensic Medicine Government Medical CollegeThiruvananthapuramKeralaIndia Achutha Menon Centre for Health science studies Sree Chitra Tirunal Institute for Medical Sciences and TechnologyThiruvananthapuramKeralaIndia

Aims:The aim was to analyze the homicide pattern in south Kerala from autopsies conducted between 2002 and ***:Exploring the age and gender distribution of death due to homicide,the type and distribution of injuries according to the region of the body,and trends of *** also tried to study the pattern of defense wounds in homicidal cases and characteristics in dyadic deaths(homicide-suicide).Materials and Methods:It was a retrospective descriptive *** setting was the Department of Forensic Medicine,state Medico-Legal Institute,Government Medical College(GMC),*** cases of autopsies with an alleged history of homicide,between 2002 and 2016,done at Mortuary of GMC,Thiruvananthapuram,were included in the *** of all cases of an alleged history of homicide from January 1,2002 to December 31,2016 were ***:957 cases were *** annual incidence of homicide is declining after *** adult males(31T0 years)are the most common group involved(24.97%).Head injury was the most common cause of death(43.68%).The head was the most common area to be affected in fatal blunt force injuries(49%)while the chest was involved commonly in fatal sharp force injuries(36%).Females were more often the homicide victims in ***-wife and fatherchild combination was the most common pairs in dyadic ***:The characteristics which were associated with the homicides were generally in agreement with the existing forensic *** findings encourage examining the motives of homicide and potential sociocultural factors affecting the victims and possibly the *** also found that the murder-suicide cases differed from the homicides requiring a separate domain of understanding and subsequent investigations.

关键词： Death homicide homicide-suicide Kerala murder Thiruvananthapuram

Phytotoxicity of cadmium on protein, proline and antioxidant enzyme activities in growing Arachis hypogaea L. seedlings

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Journal of Environmental sciences 2008年第2期20卷 199-206页

作者： N Dinakar P C Nagajyothi s suresh Y Udaykiran T Damodharam Department of Environmental sciences Sri Venkateswara UniversityTirupatiAndhra Pradesh-517 502India.

Phytotoxicity of cadmium on growing Arachis hypogaea L. seedlings was studied. seeds were exposed to 25, 50, and 100 μmol/L CdCl2 concentrations, for a period of 10, 15, 20 and 25 d. The extent of damage to chlorophyll, protein, proline, nitrate and nitrite reductase, antioxidant enzyme activity in leaves and roots were evaluated after 10 d of cadmium stress. The higher concentration of cadmium （100 μmol/L） resulted （leaves and roots） total chlorophyll 91.01%, protein 79.51%, 83.61%, nitrate reductase 79.39%, 80.72% and nitrite reductase 77.07%, 75.88% activity decreased with increase in cadmium concentrations and exposure periods. Cadmium caused significant changes in the activity of antioxidative enzymes. Contrastingly Cd treated plant tissues showed an increase in proline 159.87%, 239.6%, gluthion reductase （GR） 337.72%, 306.14%, superoxide disumutase （sOD） 688.56%, 381.72%, ascorbate peroxidase （APX） 226.47%, 252.14%, peroxidase （POD） 72.19%, 60.29% and catalase （CAT） 228.96%, 214.74% as compared to control. Cadmium stress caused a significant increase in the rate of sOD activity in leaves and roots of plant species. Results show the crop A. hypogaea is highly sensitive even at very low cadmium concentrations.

关键词： toxicological effects cadmium protein proline antioxidant enzymes

Novel anlytical solution to the damped Kawahara equation and its application for modeling the dissipative nonlinear structures in a fluid medium

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Journal of Ocean Engineering and science 2022年第5期7卷 492-497页

作者： Noufe H.Aljahdaly s.A.El-Tantawy Department of Mathematics Faculty of Sciences and Arts-Rabigh campusKing Abdulaziz UniversityJeddahSaudi Arabia Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Research Center for Physics(RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversitySaudi Arabia

A novel approximate analytical solution to the linear damped Kawahara equation using a suitable hypothesis is reported for the first *** on the exact solutions(such as solitary waves,cnoidal waves,etc.)of the undamped Kawahara equation,the dissipative nonlinear structures like dissipative solitons and cnoidal waves are *** obtained solution is considered a general solution,i.e.,it can be applied for studying the properties of all dissipative traveling waves described by the linear damped Kawahara *** technique is not limited to solve the linear damped Kawahara equation only,but it can be used for solving a large number of non-integrable evolution equations related to the realistic natural ***,the maximum global residual error in the whole space-time domain is estimated for checking the accuracy of the obtained *** obtained solutions can help many researchers in explaining the ambiguities about the mechanisms of propagation of nonlinear waves in complex systems such as seas,oceans,plasma physics,and much more.

关键词： semi-analytical solutions Damped Kawahara equation A collisional plasma Dissipative Kawahara solitons and cnoidal waves

Affine transformation of virtual 3D object using 2D localization of fingertips

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Virtual Reality & Intelligent Hardware 2020年第6期2卷 534-555页

作者： Mohammad Mahmudul ALAM s.M.Mahbubur RAHMAN Department of Electrical and Electronic Engineering Bangladesh University of Engineering and TechnologyDhaka 1000Bangladesh

Background Interactions with virtual 3D objects in the virtual reality(VR)environment using the gesture of fingers captured in a wearable 2D camera have emerging applications in *** This paper presents an approach of a two-stage convolutional neural network,one for the detection of hand and another for the *** purpose of VR environments is to transform a virtual 3D object with affine parameters by using the gesture of thumb and index *** To evaluate the performance of the proposed system,one existing,and another developed egocentric fingertip databases are employed so that learning involves large variations that are common in *** results show that the proposed fingertip detection system outperforms the existing systems in terms of the precision of *** The interaction performance of the proposed system in the VR environment is higher than that of the existing systems in terms of estimation error and correlation between the ground truth and estimated affine parameters.

关键词： Affine transformation Detection of fingertips Detection of hand Human-computer interaction Virtual reality

A new insertion sequence for incremental Delaunay triangulation

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Acta Mechanica sinica 2013年第1期29卷 99-109页

作者： Jian-Fei Liu Jin-Hui Yan s.-H. Lo Department of Mechanics and Aerospace Engineering College of EngineeringPeking University Department of Civil Engineering University of Hong Kong

Incremental algorithm is one of the most popular procedures for constructing Delaunay triangulations （DTs）. However, the point insertion sequence has a great impact on the amount of work needed for the construction of DTs. It affects the time for both point location and structure update, and hence the overall computational time of the triangulation algorithm. In this paper, a simple deterministic insertion sequence is proposed based on the breadth-first-search on a Kd-tree with some minor modifications for better performance. Using parent nodes as search-hints, the proposed insertion sequence proves to be faster and more stable than the Hilbert curve order and biased randomized insertion order （BRIO）, especially for non-uniform point distributions over a wide range of benchmark examples.

关键词： Incremental Delaunay triangulation algorithms Insertion sequences Kd-tree

A review of ferroelectric materials for high power devices

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Journal of Materiomics 2022年第4期8卷 739-752页

作者： sergey I.shkuratov Christopher s.Lynch Loki Incorporated 1334 Royal RoadNorwoodMO65717USA Bourns College of Engineering University of California at RiversideCA92521USA

Compact autonomous ultrahigh power density energy storage and power generation devices that exploitthe spontaneous polarization of ferroelectric materials are capable of producing hundreds of kilovoltvoltages,multi-kiloampere currents,and megawatt power levels for brief interval of *** storagelife of these devices is four orders of magnitude longer than that for electrochemical batteries andelectrochemical *** is an up to date survey of ferroelectric materials used for these highpower *** types of ferroelectric ceramics possess the ability to be depolarized under adia-batic compression and can be successfully used for high power *** addition to bulk ferro-electric ceramics,multilayer ferroelectric films are very efficient materials for high power *** importance is the ability of relaxor ferroelectric single crystals to produce significantly higherelectric charge density and energy density than ceramics,making them promising materials for highpower *** provided is a brief survey of recent developments of ferroelectric materials forhigh energy density and power density dielectric *** ceramics have been developed,including antiferroelectric and relaxor antiferroelectric solid solutions,providing high energy densityand efficiency simultaneously.

关键词： Energy storage Ferroelectric Antiferroelectric Relaxor High power density

JOINT INVEsTIGATION OF ROTATING FLOW WITH VORTEX BREAKDOWN UsING CFD, VIsUALIZATION AND LDV

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Journal of Hydrodynamics 2005年第4期17卷 455-458页

作者： LIU Ying-zheng CHEN Han-ping KOYAMA Hide s. school of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai 200030 China Department of Mechanical Engineering Tokyo Denki University Tokyo Japan

Vortex breakdown of the steady axisymmetic rotating flow in a confined cylindrical container with a rotating endwall was numerically and experimentally studied. High-quality precision-controlled turntable facilities were established at shanghai Jiaotong University and Tokyo Denki University independently. Collaborative investigations of vortex breakdown were carried out using CFD, Laser Doppler Velocimetry （LDV） and streakline visualization, respectively. The characteristics of vortex breakdown were delineated in terms of comparative investigation using numerical and experimental results. sIMPLEC scheme and FMG multigrid was applied to numerical simulation. Numerical simulation was extensively compared with streakline visualization and LDV measurements, showing qualitative and quantitative agreements.

关键词： vortex breakdown CFD visualization Laser Doppler Velocimetry (LDV)

Efficient WENO-Based Prolongation strategies for Divergence-Preserving Vector Fields

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Communications on Applied Mathematics and Computation 2023年第1期5卷 428-484页

作者： Dinshaw s.Balsara saurav samantaray sethupathy subramanian Department of Physics University of Notre DameNotre DameINUSA Department of ACMs University of Notre DameNotre DameINUSA

Adaptive mesh refinement(AMR)is the art of solving PDEs on a mesh hierarchy with increasing mesh refinement at each level of the *** treatment on AMR hierarchies requires accurate prolongation of the solution from a coarse mesh to a newly defined finer *** scalar variables,suitably high-order finite volume WENO methods can carry out such a ***,classes of PDEs,such as computational electrodynamics(CED)and magnetohydrodynamics(MHD),require that vector fields preserve a divergence *** primal variables in such schemes consist of normal components of the vector field that are collocated at the faces of the *** a result,the reconstruction and prolongation strategies for divergence constraint-preserving vector fields are necessarily more *** this paper we present a fourth-order divergence constraint-preserving prolongation strategy that is analytically *** to higher orders using analytically exact methods is very *** overcome that challenge,a novel WENO-like reconstruction strategy is invented that matches the moments of the vector field in the faces,where the vector field components are *** approach is almost divergence constraint-preserving,therefore,we call it *** make it exactly divergence constraint-preserving,a touch-up procedure is developed that is based on a constrained least squares(CLsQ)method for restoring the divergence constraint up to machine *** the touch-up,it is called *** is shown that refinement ratios of two and higher can be *** item of broader interest in this work is that we have also been able to invent very efficient finite volume WENO methods,where the coefficients are very easily obtained and the multidimensional smoothness indicators can be expressed as perfect *** demonstrate that the divergence constraint-preserving strategy works at several high orders for divergence-free vector fields as well as vecto

关键词： PDEs Numerical schemes Mimetic