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Processing of chromite ultra-fines in a water only cyclone

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International journal of Mining Science and Technology 2017年第6期27卷 1057-1063页

作者： Tripathy Sunil kumar Bhoja sharath kumar Murthy Y. Rama Research and Development Division Tata Steel Ltd. Jamshedpur 831001 India Process Technology Group Tata Steel Ltd. Jamshedpur 831001 India

In the present investigation, an attempt is made to examine the interdependencies among the operating parameters and their interactional effect on the separation performance of a water-only cyclone for treating ferruginous chromite fines. Statistically designed experiments are carried out, and empirical models are developed for the critical response parameters, i,e., yield(%) to underflow, grade(%Cr_2O_3 and%SiO_2)and Cr:Fe ratio of the underflow stream. Further, using these empirical models, operating regime of the process parameters is optimized to obtain the peak performance of water-only cyclone. Also, efforts are made to validate the prediction models with the experimental results.

关键词： Water only cyclone Chromite beneficiation Optimization Factorial designed experiment Statistical modelling

Understanding Performance for Two 802.11 Competing Flows

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journal of Computer Science & Technology 2008年第3期23卷 365-376页

作者： Michael j.Feeley Brendan Cully sharath j.George Department of Computer Science University of British ColumbiaVanconverCanada

It is well known that 802.11 suffers from both inefficiency and unfairness in the face of competition and interference. This paper provides a detailed analysis of the impact of topology and traffic type on network performance when two flows compete with each other for airspace. We consider both TCP and UDP flows and a comprehensive set of node topologies. We vary these topologies to consider all combinations of the following four node-to-node interactions：（1） nodes unable to read or sense each other, （2） nodes able to sense each other but not able to read each other＇s packets and nodes able to communicate with （3） weak and with （4） strong signal. We evaluate all possible cases through simulation and show that the cases can be reduced to 9 UDP and 10 TCP 802.11g models with similar efficiency/fairness characteristics. We also validate our simulation results with extensive experiments conducted in a laboratory testbed. These more detailed models improve on previous work such as hidden-/exposed-terminal categorization and are thus better suited as a basis for adaptive techniques to improve performance in 802.11 multi-hop WLAN or Mesh Networks.

关键词： 802.11 wireless unfairness two-flow competition network topology

Transition Metal Free Chemoselective Reduction ofα,β-Unsaturated Ketones to Saturated Ketones Using Tosyl Hydrazide as a Hydrogen Donor

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Chinese journal of Chemistry 2015年第2期33卷 181-184页

作者： Yarabally R Girish Kanchipura R Raghavendra Dasappa Nagaraja Kothanahally S sharath kumar Sheena Shashikanth Deparment of Studies in Chemistry ManasagangothriUniversity of MysoreMysore 570006India Department of PG Studies in Chemistry Government Science CollegeChitradurga 577501India

An efficient,inexpensive and simple method for the reduction of variousα,β-unsaturated ketones to corre-sponding saturated ketones using tosyl hydrazide as a hydrogen donor in DMF using calcium oxide powder has been reported.A variety of enones underwent reduction without forming undesirable side *** chemose-lectivity,broad functional group tolerance and good yields are the noteworthy features of this protocol.

关键词： α,β-unsaturated carbonyl compounds tosyl hydrazide transition metal free saturated ketones

Functional outcome of tibial fracture with acute compartment syndrome and correlation to deep posterior compartment pressure

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World journal of Orthopedics 2017年第5期8卷 385-393页

作者： Saumitra Goyal Monappa A Naik Sujit kumar Tripathy sharath K Rao Department of Orthopedics Kasturba Medical College Manipal University Department of Orthopedics All India Institute of Medical Sciences

AIM To measure single baseline deep posterior compartment pressure in tibial fracture complicated by acute compartment syndrome(ACS) and to correlate it with functional *** Thirty-two tibial fractures with ACS were evaluated clinically and the deep posterior compartment pressure was measured. Urgent fasciotomy was needed in 30 patients. Definite surgical fixation was performed either primarily or once fasciotomy wound was healthy. The patients were followed up at 3 mo, 6 mo and one year. At one year, the functional outcome [lower extremity functional scale(LEFS)] and complications were *** Three limbs were amputated. In remaining 29 patients, the average times for clinical and radiological union were 25.2 ± 10.9 wk(10 to 54 wk) and 23.8 ± 9.2 wk(12 to 52 wk) respectively. Nine patients had delayed union and 2 had nonunion who needed bone grafting to augment healing. Most common complaint at follow up was ankle stiffness(76%) that caused difficulty in walking,running and squatting. Of 21 patients who had paralysis at diagnosis, 13(62%) did not recover and additional five patients developed paralysis at follow-up. On LEFS evaluation, there were 14 patients(48.3%) with severe disability, 10 patients(34.5%) with moderate disability and 5 patients(17.2%) with minimal disability. The mean pressures in patients with minimal disability, moderate disability and severe disability were 37.8, 48.4 and 58.79 mmH g respectively(P jority of patients. These patients are prone for delayed union and nonunion; however, long term disability is mainly because of severe soft tissue contracture. Intracompartmental pressure(ICP) correlates with functional disability; patients with relatively high ICP are prone for poor functional outcome.

关键词： Compartment syndrome Leg Tibial fracture Deep posterior compartment Intracompartmental pressure Functional outcome

Retrieval of flower videos based on a query with multiple species of flowers

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Artificial Intelligence in Agriculture 2021年第1期5卷 262-277页

作者： V.K.jyothi V.N.Manjunath Aradhya Y.H.sharath kumar D.S.Guru Department of Studies in Computer Science ManasagangothriUniversity of MysoreMysore 570006KarnatakaIndia Department of Computer Applications JSS Science and technology UniversityMysoreKarnatakaIndia Department of Information Science and Engineering Maharaja Institute of Technology Mysore(MITM)Manday 571438KarnatakaIndia

Searching,recognizing and retrieving a video of interest froma large collection of a video data is an instantaneous *** requirement has been recognized as an active area of research in computer vision,machine learning and pattern *** video recognition and retrieval is vital in the field of floriculture and *** this paper we propose a model for the retrieval of videos of ***,videos are represented with keyframes and flowers in keyframes are segmented from their ***,the model is analysed by features extracted from flower regions of the keyframe.A Linear Discriminant Analysis(LDA)is adapted for the extraction of discriminating *** Support VectorMachine(MSVM)classifier is applied to identify the class of the query *** have been conducted on relatively large dataset of our own,consisting of 7788 videos of 30 different species of flowers captured from three different ***,retrieval of flower videos is addressed by the use of a query video consisting of a flower of a single *** this work we made an attempt to develop a system consisting of retrieval of similar videos for a query video consisting of flowers of different species.

关键词： Flower region of interest(FRoI) Linear discriminant analysis(LDA) Retrieval of flower videos Multiclass support vector machine

Effect of multiple rings on side force over an ogive-cylinder body at subsonic speed

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Chinese journal of Aeronautics 2018年第6期31卷 1181-1188页

作者： Priyank kumar j.K.PRASAD Department of Space Engineering & Rocketry Birla Institute of Technology

Experiments and computations were performed over an ogive-cylinder body having an lift-to-drag ratio of 16 at a diameter Reynolds number of 29000. The side force on the slender body augments with increasing angles of attack for the case without a ring. This increase was mainly due to the increase in the asymmetry of the existing vortex pair in the wake of the body. Attempts were made to completely reduce the existing side force at the angle of attack ranging from 35° to 45°.Three rectangular cross-sectioned circumferential rings having a height of 3% of the local diameter were placed at axial distances of 2.5, 3.5 and 4.5 times the base diameter from the tip of the body so as to reduce the side force. The results obtained indicate that inclusion of three rings completely alleviated the side force on the slender body at the angle of attack ranging from 0° to 45°. The presence of rings was found to alter the growth of the vortices that helped in the reduction of the side force. Computations performed were in reasonable agreement with the experiments.

关键词： Asymmetric vortex High angle of attack Ogive Side force Slender body Vortex lift

Embryo-to-lamella transition of grain boundary twins in magnesium

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journal of Magnesium and Alloys 2023年第12期11卷 4485-4497页

作者： Mariyappan Arul kumar Irene j Beyerlein Materials Science and Technology Division Los Alamos National LaboratoryLos AlamosNM 87545USA Mechanical Engineering Department Materials DepartmentUniversity of CaliforniaSanta BarbaraCA 93106USA

A combined experimental and computational analysis is performed to investigate the less commonly studied embryo-to-lamella transition of deformation twins in magnesium. This work aims to understand the structural variables controlling the embryo-to-lamella transition from grain boundaries. Statistical analysis of hundreds of early-stage twins in the lightly deformed microstructure reveals a prevailing wedge shape,with a much thicker base along the grain boundary(GB) where they originate and a thinner tip terminating in the crystal. The analysis also shows that the GB base is super thick and identifies a minimum GB twin thickness among all early-stage twins that is about one micron. A crystal plasticity-based full-field model is employed to calculate the driving forces to migrate the boundary of a three-dimensional GB twin embryo. The stress analysis, considering a full range of embryo shapes and neighboring grain orientations, indicate that the twin embryo is most likely going to form a wedge shape when it first propagates. The calculations predict that the thickness of the embryo at the GB needs to be significantly larger than its length into the crystal in order to propagate into the crystal. The analysis finds that the more aligned the twin embryo variant is with basal slip in the neighboring grain, the thinner the twin embryo needed for propagation.

关键词： Magnesium Twin embryo Crystal plasticity Nucleation Grain neighbor

Three Phase Composite Cylinder Assemblage Model for Analyzing the Elastic Behavior of MWCNT-Reinforced Polymers

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Computers, Materials & Continua 2018年第1期54卷 1-20页

作者： Puneet kumar j.Srinivas Research Scholar Mechanical Engineering DepartmentNational Institute of Technology RourkelaOdisha-769008India Associate Professor Mechanical Engineering DepartmentNational Institute of Technology RourkelaOdisha-769008India

Evolution of computational modeling and simulation has given more emphasis on the research activities related to carbon nanotube(CNT)reinforced polymer composites *** paper presents the composite cylinder assemblage(CCA)approach based on continuum mechanics for investigating the elastic properties of a polymer resin reinforced by multi-walled carbon nanotubes(MWCNTs).A three-phase cylindrical representative volume element(RVE)model is employed based on CCA technique to elucidate the effects of inter layers,chirality,interspacing,volume fraction of MWCNT,interphase properties and temperature conditions on the elastic modulus of the *** interface region between CNT and polymer matrix is modeled as the third phase with varying material *** constitutive relations for each material system have been derived based on solid mechanics and proper interfacial traction continuity conditions are *** predicted results from the CCA approach are in well agreement with RVE-based finite element *** outcomes reveal that temperature softening effect becomes more pronounced at higher volume fractions of CNTs.

关键词： Multi-walled carbon nanotube composite cylinder assemblage continuum representative volume element variable interphase

Optimal treatment of stratified Carreau and Casson nanofluids flows in Darcy-Forchheimer porous space over porous matrix

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Applied Mathematics and Mechanics(English Edition) 2020年第11期41卷 1651-1670页

作者： R.kumar R.kumar S.A.SHEHZAD A.j.CHAMKHA Department of Mathematics Central University of Himachal PradeshDharamshala 273001India Department of Mathematics COMSATS University IslamabadSahiwal 57000Pakistan Institute of Research and Development Duy Tan UniversityDa Nang 550000Vietnam Institute of Theoretical and Applied Research(ITAR) Duy Tan UniversityHanoi 100000Vietnam

A comparative three-dimensional(3D)analysis for Casson-nanofluid and Carreau-nanofluid flows due to a flat body in a magnetohydrodynamic(MHD)stratified environment is *** is estimated to be suspended in a Darcy-Forchheimer *** and Dufour responses are also accommodated in the flow field.A moving(rotating)coordinate system is exercised to examine the bidirectionally stretched flow fields(flow,heat transfer,and mass transfer).Nanofluid is compounded by taking ethylene glycol/sodium alginate as base fluid and ferric-oxide(Fe3O4)as *** equations are handled by the application of optimal homotopy asymptotic method(OHAM),where convergence parameters are optimized through the classical least square *** novel mechanism(hidden physics)due to appearing parameters is explored with the assistance of tabular and graphical *** reveal the double behavior state for temperature field with thermal stratification/Dufour number,and for concentration field with Soret number due to the presence of turning points.

关键词： thermal-solutal stratification Soret-Dufour effect Casson-Carreau nanofluid model porous matrix