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Forest structure and anthropogenic pressures in the Pachmarhi biosphere reserve of India

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Journal of Forestry research 2015年第4期26卷 867-874页

作者： Chandra prakash Kala Ecosystem & Environment Management Indian Institute of Forest Management

A critical first step in establishing biosphere reserves--under the Man and Biosphere Programme of UNESCO--is to generate baseline information for future courses of action. The present study aims to assess the structure and composition of forests--along with anthro- pogenic pressures mounting on these forests in the buffer zone of one such biosphere reserves--the Pachmarhi bio- sphere reserve of India. The quadrat method was employed for sampling vegetation, and information on anthropogenic pressures was collected by conducting interviews with local people and forest officials and collecting it from secondary sources. A total of 39 tree species were sampled in 82 quadrats; of these 26 tree species were in standing stage, 25 in sapling, and 35 in seedling. Chloroxylon swi- etenia emerged as the most dominant tree species having highest importance value index, followed by Tectona grandis, Terminalia tomentosa, and Hardwickia binata. Nine tree species and their saplings, including Sterculia urens and Terminalia arjuna, were exploited so badly that they were only found in the seedlings stage. The unavail- ability of standing trees of 12 important tree species including Aegle marmelos and Phyllanthus emblicaindicates the intensity and gravity of anthropogenic pres- sures on these important tree species. If the present anthropogenic pressure continues, which has inhibited the regeneration of several tree species, then substantial neg- ative ecological and societal consequences can be expected.

关键词： Pachmarhi biosphere reserve Tropicalforest Forest composition Forest structure regeneration Anthropogenic pressures

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Land Use Changes in Himalaya and Their Impacts on Environment, Society and Economy: A Study of the Lake region in Kumaon Himalaya, India

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Advances in Atmospheric Sciences 2008年第6期25卷 1029-1042页

作者： prakash TIWArI Martin Luther University Halle-Wittenberg

The traditional resource use structure in Himalaya has transformed considerably during the recent past, mainly owing to the growth of population and the resultant increased demand of natural resources in the region. This transformation in resource use practices is particularly significant in the densely populated tracts of Himalaya. As a result, cultivated land, forests, pastures and rangelands have been deteriorated and depleted steadily and significantly leading to their conversion into degraded and non-productive lands. These rapid land use changes have not only disrupted the fragile ecological equilibrium in the mountains through indiscriminate deforestation, degradation of land resources and disruption of the hydrological cycle, but also have significant and irreversible adverse impacts on the rural economy, society, livelihood and life quality of mountain communities. It has been observed that the agricultural production has declined, water sources are drying up fast due to decreased ground water recharge and a large number of villages are facing enormous deficit of critical resources, such as food, fodder, firewood and water, mainly due to unabated deforestation. As a result, the rural people, particularly the women, have to travel considerably long distances to collect fodder and firewood and to fetching water. It is therefore highly imperative to evolve a comprehensive and integrated land use framework for the conservation of the biophysical environment and sustainable development of natural resources in Himalaya. The land use policy would help local communities in making use of their natural resources scientifically and judiciously, and thus help in the conservation of the biophysical environment and in the increasing of the productivity of natural resources. The study indicates that conservation of forests and other critical natural resources through community participation, generation of alternative means of livelihood, and employment in rural areas can

关键词： subsistence agriculture population growth resource use pattern urbanization deforestation hydrological disruptions resource deficit integrated land use framework

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A model for virtual network embedding across multiple infrastructure providers using genetic algorithm

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Science China(Information Sciences) 2017年第4期60卷 101-112页

作者： Isha PATHAK Deo prakash VIDYArTHI School of Computer and Systems Sciences Jawaharlal Nehru University

Network virtualization is an important aspect in cloud computing, where network is assumed to be consisting of infinite amount of nodes and links. The substrate network(physical network), has limited capacity and so virtual network embedding on the substrate network becomes a problem. Virtual network embedding is a computationally hard problem, considering various constraints on nodes and links. The proposed work applies Genetic Algorithm for the virtual network embedding problem for mapping multiple virtual network requests on infrastructure providers managing multiple substrate networks. Performance evaluation, through simulations,indicates that the proposed model preforms better for the performance metrics such as infrastructure provider revenue, acceptance ratio and node and link utilization in comparison to few other contemporary mapping models.

关键词： network virtualization virtual network embedding substrate network NP-hard genetic algorithm

Evaluation of machine learning algorithms for predictive reynolds stress transport modeling

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Acta Mechanica Sinica 2022年第4期38卷 78-90,I0002页

作者： Jyoti prakash Panda Hari Vijayan Warrior Department of Mechanical Engineering DIT UniversityDehradun 248001India Department of Ocean Engineering and Naval Architecture Indian Institute of Technology(IIT)Kharagpur 721302India

The application of machine learning(ML)algorithms to turbulence modeling has shown promise over the last few years,but their application has been restricted to eddy viscosity based closure *** this article,we discuss the rationale for the application of machine learning with high-fidelity turbulence data to develop models at the level of reynolds stress transport *** on these rationales,we compare different machine learning algorithms to determine their efficacy and robustness at modeling the different transport processes in the reynolds stress transport *** data-driven algorithms include random forests,gradient boosted trees,and neural *** direct numerical simulation(DNS)data for flow in channels are used both as training and testing of the ML *** optimal hyper-parameters of the ML algorithms are determined using Bayesian *** efficacy of the above-mentioned algorithms is assessed in the modeling and prediction of the terms in the reynolds stress transport *** was observed that all three algorithms predict the turbulence parameters with an acceptable level of *** ML models are then applied for the prediction of the pressure strain correlation of flow cases that are different from the flows used for training,to assess their robustness and *** explores the assertion that ML-based data-driven turbulence models can overcome the modeling limitations associated with the traditional turbulence models and ML models trained with large amounts of data with different classes of flows can predict flow field with reasonable accuracy for unknown flows with similar flow *** addition to this verification,we carry out validation for the final ML models by assessing the importance of different input features for prediction.

关键词： Machine learning Pressure strain correlation Turbulence modeling CFD

A novel slot scheduling technique for duty-cycle based data transmission for wireless sensor network

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Digital Communications and Networks 2022年第3期8卷 351-358页

作者： Yogesh Tripathi Arun prakash rajeev Tripathi Department of Electronics and Communication Engineering Motilal Nehru National Institute of Technology AllahabadPrayagraj211004India

The duty cycling process involves turning a radio into an active and dormant state for conserving energy. It is a promising approach for designing routing protocols for a resource-constrained Wireless Sensor Networks (WSNs). In the duty cycle-based WSNs, the network lifetime is improved and the network transmission is increased as compared to conventional routing protocols. In this study, the active period of the duty cycle is divided into slots that can minimize the idle listening problem. The slot scheduling technique helps determine the most efficient node that uses the active period. The proposed routing protocol uses the opportunistic concept to minimize the sender waiting problem. Therefore, the forwarder set will be selected according to the node's residual active time and energy. Further, the optimum routing path is selected to achieve the minimum forwarding delay from the source to the destination. Simulation analysis reveals that the proposed routing scheme outperforms existing schemes in terms of the average transmission delay, energy consumption, and network throughput.

关键词： Duty cycle Energy model Wireless sensor network Slot scheduling technique

Wntl-regu｜ated genetic networks in midbrain dopaminergic neuron development

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Journal of Molecular Cell Biology 2014年第1期8卷 34-41页

作者： Wolfgang Wurst Nilima prakash Institute of Developmental Genetics Helmholtz Zentrum MCinchen German Research Center for Environmental Health and Technische Universit~it MCinchen-Weihenstephan Lehrstuhl for Entwicklungsgenetik Ingolst~idter Landstr. I 85764 Neuherberg Germany Deutsches Zentrum fiJr Neurodegenerative Erkrankungen (DZNE) Standort MiJnchen Schinerstr. 44 80336 MCinchen Germany Max Planck Institute of Psychiatry Kraepelinstrasse 2-10 80804 MiJnchen Germany

Neurons synthesizing the neurotransmitter dopamine exert crucial functions in the mammalian brain. The biggest and most important population of dopamine-synthesizing neurons is located in the mammalian ventral midbrain （VM）, and controls and modulates the exe- cution of motor, cognitive, affective, motivational, and rewarding behaviours. Degeneration of these neurons leads to motor deficits that are characteristic of Parkinson＇s disease, while their dysfunction is involved in the pathogenesis of psychiatric disorders including schizophrenia and addiction. Because the aetiology and therapeutic prospects for these diseases include neurodevelopmental aspects, substantial scientific interest has been focused on deciphering the mechanistic pathways that control the generation and sur- vival of these neurons during embryonic development. researches during the last decade revealed the pivotal role of the secreted Wntl ligand and its signaUing cascade in the generation of the dopamine-synthesizing neurons in the mammalian VM. Here, we summarize the initial and more recent findings that have unravelled several Wntl-controUed genetic networks required for the proliferation and commitment of VM progenitors to the dopaminergic cell fate during midgestational embryonic stages, and for the correct differentiation of these progenitors into postmitotic dopamine-synthesizing neurons at late midgestational embryonic and foetal stages.

关键词： Wntl dopamine neuron ventral midbrain mouse

Plasma Spray Deposition of HA-TiO2 on β-phase Ti-35Nb-7Ta-5Zr Alloy for Hip Stem: Characterization of Bio-mechanical Properties, Wettability, and Wear resistance

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Journal of Bionic Engineering 2020年第5期17卷 1029-1044页

作者： Harjit Singh Chander prakash Sunpreet Singh School of Mechanical Engineering Lovely Professional UniversityPhagwaraPunjab-144411India Mechanical Engineering National University of SingaporePincode-119244Singapore

In this work,a biomimetic coating of hydroxyapatite(HA)-and titania(TiO2)was deposited on low elastic β-phase Ti-35Nb-7Ta-5Zr(β-TNTZ)alloy by plasma spray deposition technique for orthopedic *** effect of TiO2 reinforcement on microstructure,mechanical properties,and bioactivity was *** morphology,coating thickness,elemental composition,and phase composition of the developed coatings were *** biomechanical behavior of the deposited coatings was investigated in terms of surface hardness,elastic modulus,and adhesion *** was found from the morphological investigation that the TiO2 reinforcement improves the microstructure and prevents the formation of defects in the *** biomimetic HA-TiO2 coated surface possessed pores,size ranging from 200 nm-600 nm that benefits the apatite growth and *** EDS spectrum,mapping,and XrD analysis show that the deposited layerβ-TCP,CaO,TTCP,TiO2 *** HA-TiO2 coating exhibits a very dense and thick layer of 100μm-125am that exhibits excellent adhesion strength to offer mechanical interlocking to prevent *** alloying of TiO2 improves the hardness from 1.67 GPa to 2.95 GPa that enhances the wear *** was found that HA-TiO2 coating exhibits better hydrophilic and biocompatible surface as compared to HA-coating.

关键词： β-phase Ti-35Nb-7Ta-5Zr alloy plasma spray porosities bio-ceramic coating nano-indentation hardness bond strength wettability

Static/dynamic friction and wear of some selected polymeric materials for conformal tribo-pairs under boundary lubrication conditions

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Friction 2013年第3期1卷 232-241页

作者： Daniel NILSSON Braham prakash Bosch rexroth Mellansel AB MellanselSweden Division of Machine Elements Department of Engineering Sciences and MathematicsLuleåUniversity of TechnologyLuleåSweden

This work is aimed at investigating the friction and wear performance of different polymeric materials having potential for hydraulic system components under lubricated sliding conditions against a steel counter face.A pin-on-disc test configuration was used for the experimental *** different polymeric materials selected for these studies were commercial polyimides(PI),polyether ether ketone(PEEK),and *** of these materials were bulk materials whereas others were used as coatings applied on to the cast iron *** tribological characteristics of the polymers were compared with a reference grey cast *** frictional characteristics were evaluated in both static and dynamic *** results have shown that by using polymeric materials it is possible to reduce breakaway friction by an order of magnitude compared to grey cast ***,the breakaway friction increased significantly after the wear *** polymeric materials having lowest breakaway friction have shown the highest wear with the exception of the PEEK-PTFE coating which showed low *** with graphite fillers also showed low wear but it resulted in relatively high *** carbon fibre reinforced materials resulted in unstable friction as well as higher wear compared to the PI materials with graphite fillers.

关键词： polymer tribology static friction dynamic friction and lubricated wear

Lie Triple Derivations of the Lie Algebra of Dominant Block Upper Triangular Matrices

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Algebra Colloquium 2018年第3期25卷 475-492页

作者： prakash Ghimire Huajun Huang Department of Mathematics and Physical Sciences LSU of Alexandria Alexandria LA 71302 USA Department of Mathematics and Statistics Auburn University Auburn AL 36849 USA

Let N be the Lie algebra of all n x n dominant block upper triangular matrices over a field F. In this paper, we explicitly describe all Lie triple derivations of N when char（F） ≠ 2. As an application, we character... 详细信息

关键词： Lie triple derivation block upper triangular matrix Lie algebra