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International Journal of Digital Earth 2009年第2期2卷 122-133页

作者： Kailasam Muni krishna Department of Meteorology and Oceanography Andhra UniversityVisakhapatnam-530003India

Upwelling favourable winds along the Indian coasts were studied using a highresolution(9 km grid)atmospheric mesoscale model(MM5)reanalysis from 1 to 5 June 2006,off the west coast of India and from 5 to 10 December 2005,off the east coast of *** winds are verified with satellite winds at two *** wind hind-casts from the above periods reveal narrow bands(about 10×50 km)of strong winds to the coast and adjacent to the major coastal *** bands,which are sub-grid scale in operational models,were capable of generating local upwelling greater than 10 m/*** the mean and spatial components of the model alongshore wind increase by a factor of 3 to 4 from the south to the north along the west coast,and by a factor of 2 to 3 from the north to the south along the east coast of *** field increases will drive enhanced ocean upwelling along the west coast of India,and the new hypothesis suggests that the variations in local wind may contribute to the coastal upwelling in this region.

关键词： coastal upwelling QuikSCAT satellite wind variability AVHRR MM5

Modeling and multi-response optimization of machining performance while turning hardened steel with self-propelled rotary tool

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Advances in Manufacturing 2015年第1期3卷 84-95页

作者： Thella Babu Rao A.Gopala krishna Ramesh Kumar Katta Konjeti Rama krishna Department of Mechanical Engineering GITAM UniversityHyderabad 502329Andhra PradeshIndia Department of Mechanical Engineering University College of EngineeringJNTUKKakinada 533003Andhra PradeshIndia Productionisation & Technology Transfer Defence R&D LaboratoryKanchanbaghHyderabad 500058Andhra PradeshIndia

There are many advanced tooling approaches in metal cutting to enhance the cutting tool performance for machining hard-to-cut materials. The self propelled rotary tool （SPRT） is one of the novel approaches to improve the cutting tool performance by providing cutting edge in the form of a disk, which rotates about its principal axis and provides a rest period for the cutting edge to cool and allow engaging a fresh cutting edge with the work piece. This paper aimed to present the cutting performance of SPRT while turning hardened EN24 steel and optimize the machining conditions. Surface roughness （Ra） and metal removal rate （rMMR） are considered as machining perfor- mance parameters to evaluate, while the horizontal incli- nation angle of the SPRT, depth of cut, feed rate and spindle speed are considered as process variables. Initially, design of experiments （DOEs） is employed to minimize the number of experiments. For each set of chosen process variables, the machining experiments are conducted on computer numerical control （CNC） lathe to measure the machining responses. Then, the response surface method- ology （RSM） is used to establish quantitative relationships for the output responses in terms of the input variables. Analysis of variance （ANOVA） is used to check the adequacy of the model. The influence of input variables on the output responses is also determined. Consequently, these models are formulated as a multi-response optimi- zation problem to minimize the Ra and maximize the rMMR simultaneously. Non-dominated sorting genetic algorithm-II （NSGA-II） is used to derive the set of Pareto-optimal solutions. The optimal results obtained through the pro- posed methodology are also compared with the results of validation experimental runs and good correlation is found between them.

关键词： Self-propelled rotary turning ~ Empiricalmodeling ~ Response surface methodology (RSM) - Multi-objective formulation - Optimization - Non-dominatedsorting genetic algorithm-II (NSGA-II)

Analysis of pressure characteristics under laminar and turbulent flow states inside the pilot stage of a deflection flapper servo-valve:Mathematical modeling with CFD study and experimental validation

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Chinese Journal of Aeronautics 2020年第3期33卷 1107-1118页

作者： Bijan krishna SAHA Songjing LI Xinbei LV Department of Fluid Control and Automation Harbin Institute of TechnologyHarbin 150001China

Electro-hydraulic servo-valves are widely used components in the mechanical industry,aerospace and aerodynamic devices which precisely control the airplane or missile *** to the small size and complex structure in the pilot stage of deflection flapper servo-valves,accurate mathematical models for the flow and pressure characteristics have always been very difficult to be *** this paper,mathematical models for the pilot stage of deflection flapper servo-valve are investigated to overcome some gaps between the theoretical formulation and overall performance of the valve by considering different flow ***,a mathematical model of the velocity distribution at the flapper groove exit is established by using Schlichting velocity equations for incompressible laminar fluid ***,when the flow becomes turbulent,a mathematical model of pressure characteristics in the receiving ports is built on the basis of the assumption of the collision between the liquid and the jet as the impact of the jet on a moving block of fluid *** verify the analytical models for both laminar and turbulent flows,the pressure characteristics of the deflection flapper pilot stage are calculated and tested by using numerical simulation and *** verification of the theory is also *** computed numerical and analytical results show a good agreement with experimental data.

关键词： Computational fluid dynamics(CFD) Deflection flapper servovalve Laminar flow Pressure characteristics Servo-valve Turbulent submerged jet

Effect of traditional management practices on woody species composition and structure in montane subtropical forests of Meghalaya,Northeast India

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Journal of Mountain Science 2017年第8期14卷 1500-1512页

作者： Aabid Hussain MIR krishna UPADHAYA Department of Environmental Studies North-Eastern Hill University Department of Basic Sciences and Social Sciences School of TechnologyNorth-Eastern Hill University

In Meghalaya, northeast India, the local people have the tradition of managing forest resources since early ages. The management practice varies and there are forests with high degree of protection, where no extraction(sacred forests) is allowed. There are also forests with moderate-level of protection and-extraction(reserved forests) as well as forests with low level of protection and open extraction(village forests). The present study was conducted to understand the impact of this traditional management system on the level of human disturbance, and on community composition and structure of the forests in Khasi hills of Meghalaya. The result revealed that disturbance index was low, whereas species richness, density and basal cover were significantly high in forests with high degree of protection(sacred forest) than those with low protection(reserved and village forest). Majority of endemic and threatened plant species were restricted to sacred forests as compared to the other forest types. Though these practices have ensured the sustainable use of forest resources by the local people but due to increased human-pressure and-disturbances, more effective conservation strategies need to be undertaken. Therefore, providing alternatives for fuelwood to local people, environmental education, encouraging afforestation and developmental activities involving local communities are recommended.

关键词： Forest conservation Human disturbance Extraction Restricted forest Sacred forest Villageforest

Removal and recovery of toxic nanosized Cerium Oxide using eco-friendly Iron Oxide Nanoparticles

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Frontiers of Environmental Science & Engineering 2020年第1期14卷 175-184页

作者： Kanha Gupta Nitin Khandelwal Gopala krishna Darbha Department of Chemical Sciences USER KolkataMohanpurWest BengalPincode 741246India Environmental Nanoscience Laboratory Department of Earth SciencesUSER KolkataMohanpurWest BengalPincode 741246India Center for Climate&Environmental Studies USER KolkataMohanpurWest BengalPincode 741246India

Increasing applications of metal oxide nanoparticles and their release in the natural environment is a serious concern due to their toxic ***,it is essential to have eco-friendly solutions for the remediation of toxic metal oxides in an aqueous *** the present study,eco-friendly Iron Oxide Nanoparticles(IONPs)are synthesized using solvothermal technique and successfully characterized using scanning and transmission electron microscopy(SEM and TEM respectively)and powder X-Ray diffraction(PXRD).These IONPs were further utilized for the remediation of toxic metal oxide nanoparticle,i.e.,*** experiments were also performed in complex aqueous solutions and real water samples to check its applicability in the natural *** study was performed to show *** show that these 200 nm-sized spherical IONPs,as revealed by SEM and TEM analysis,were magnetite(Fe3O4)and contained short-range crystallinity as confirmed from XRD *** experiments show that the composite follows the pseudosecond-order kinetic *** k>0.99 for Langmuir sorption isotherm suggests chemisorption as probable removal mechanism with monolayer sorption of Ce02 NPs on *** than 80%recovery of adsorbed Ce02 NPs through ultrasonication and magnetic separation of reaction precipitate confirms reusability of *** removal%of Ce02 in various synthetic and real water samples was>90%signifying that IONPs are candidate adsorbent for the removal and recovery of toxic metal oxide nanoparticles from contaminated environmental water samples.

关键词： Adsorption toxic metal oxide remediation eco-friendly IONP Iron oxide CeO2 removal

Orchestration between ILC2s and Th2 cells in shaping type 2 immune responses

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Cellular & Molecular Immunology 2019年第3期16卷 225-235页

作者： Rama krishna Gurram Jinfang Zhu Molecular and Cellular Immunoregulation Section Laboratory of Immune System BiologyNational Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMD 20892USA

The type 2 immune response is critical for host defense against large parasites such as *** the other hand,dysregulation of the type 2 immune response may cause immunopathological conditions,including asthma,atopic dermatitis,rhinitis,and ***,a balanced type 2 immune response must be achieved to mount effective protection against invading pathogens while avoiding *** classical model of type 2 immunity mainly involves the differentiation of type 2 T helper(Th2)cells and the production of distinct type 2 cytokines,including interleukin-4(IL-4),IL-5,and *** 2 innate lymphoid cells(ILC2s)were recently recognized as another important source of type 2 *** eosinophils,mast cells,and basophils can also express type 2 cytokines and participate in type 2 immune responses to various degrees,the production of type 2 cytokines by the lymphoid lineages,Th2 cells,and ILC2s in particular is the central event during the type 2 immune *** this review,we discuss recent advances in our understanding of how ILC2s and Th2 cells orchestrate type 2 immune responses through direct and indirect interactions.

关键词： Type 2 immune response type 2 T helper cell(Th2) Group 2 innate lymphoid cell(ILC2) Allergy and asthma

Tribological Properties of A356.2/RHA Composites

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Journal of Materials Science & Technology 2012年第4期28卷 367-372页

作者： D. Siva Prasad A. Rama krishna Department of Mechanical Engineering GITAM University Visakhapatnam Andhra Pradesh India Department of Mechanical Engineering ANDHRA University Visakhapatnam Andhra Pradesh India

Rice husk ash （RHA） is one of the industrial waste byproduct available abundantly in the world. In the present work, an attempt is made to incorporate the RHA particles in the molten aluminum A356,2 alloy. The RHA particles were added into the matrix melt by creating a vortex with the help of a mechanical stirrer and the melt temperature was maintained between 800 and 850 ℃. Dry sliding wear experiments were performed in a pin on disc wear equipment against a chromium steel disc at 30 ℃. Scanning electron microscopy is used to study the wear characteristics of the unreinforced AI alloy and the A356.2/RHA composites. From the experiments it is observed that the composites exhibit higher hardness and resistance to wear as compared to unreinforced AI alloy,

关键词： Rice husk ash A356.2 Aluminum alloy Wear

A review on current status of municipal solid waste management in India

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Journal of Environmental Sciences 2015年第11期27卷 206-217页

作者： Neha Gupta krishna Kumar Yadav Vinit Kumar Institute of Environment and Development Studies Bundelkhand University

Municipal solid waste management is a major environmental issue in India. Due to rapid increase in urbanization, industrialization and population, the generation rate of municipal solid waste in Indian cities and towns is also increased. Mismanagement of municipal solid waste can cause adverse environmental impacts, public health risk and other socio-economic problem. This paper presents an overview of current status of solid waste management in India which can help the competent authorities responsible for municipal solid waste management and researchers to prepare more efficient plans.

关键词： Municipal solid waste Characteristic Management India Disposal

Ranking Modules for Integrate Testing Based on PageRank Algorithm

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Chinese Journal of Electronics 2017年第5期26卷 993-998页

作者： SUN Qi krishna Ricky MONIZ YUAN Yuyu Key Laboratory of Trustworthy Distributed Computing and Service(BUPT) Ministry of EducationBeijing University of Posts and Telecommunications

The testing industry need to prioritize the limited resources and focus on testing modules whose failure is mostly likely to cause *** paper discusses a method that can rank modules in a software package for integrate testing using the PageR ank *** this algorithm,a sequences of random walks iteratively can find a high likelihood of encountering a node,which is interpreted as it being an important performance *** experiment result prove that the proposed method actually can be used to prioritize testing of specific modules when testing resource are scarce.

关键词： Software testing Integrate testing PageRank algorithm Testing prioritize

Steady rotation of a composite sphere in a concentric spherical cavity

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Acta Mechanica Sinica 2012年第3期28卷 653-658页

作者： D.Srinivasacharya M.krishna Prasad Department of Mathematics National Institute of Technology

The problem of steady rotation of a composite sphere located at the centre of a spherical container has been investigated. A composite particle referred to in this paper is a spherical solid core covered with a permeable spherical shell. The Brinkman＇s model for the flow inside the compos- ite sphere and the Stokes equation for the flow in the spheri- cal container were used to study the motion. The torque ex- perienced by the porous spherical particle in the presence of cavity is obtained. The wall correction factor is calculated. In the limiting cases, the analytical solution describing the torque for a porous sphere and for a solid sphere in an un- bounded medium are obtained from the present analysis.

关键词： Rotation Porous sphere Solid core Stokesflow Brinkman equation Stress jump coefficient. Torque Wall correction factor