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Biodiversity and Invasibility: Distribution Patterns of Invasive Plant Species in the Himalayas, Nepal

Journal of Mountain Science 2014年第3期11卷 688-696页

作者： BHATTARAI Khem Raj M?REN Inger Elisabeth SUBEDI Suresh chandra National Herbarium and Plant Laboratories Department of Plant Resources Department of Geography University of Bergen Department of Biological Science Florida International University

Invasive plant species are exerting a serious threat to biological diversity in many regions of the world. To understand plant invasions this study aims to test which of the two plant invasiveness hypotheses; ‘low native diversity' vs. ‘high native diversity', is supported by the regional distribution patterns of invasive plant species in the Himalayas,Nepal. This study is based on data retrieved from published literatures and herbarium specimens. The relationship between invasive plant species distribution patterns and that of native plant species is elucidated by scatter plots, as well as by generalized linear models. The native plant species and invasive plant species have similar distribution patterns and the maximum number of invasive plant species is found in the same altitudinal range where the highest richness for native tree species is found. There is a clear trend of higher invasive plant richness in regions where native tree species richness is relatively ***, the native plant richness is highest in the central phytogeographic region, followed by the eastern and the western regions, respectively. The invasive plant species also follows a similar ***, the invasive plant species richness was positively correlated with anthropogenic factors such as human population density and the number of visiting tourists. This study supports the hypothesis that ‘high native diversity' supports or facilitates invasive plant species. Further, it indicates that nativeand invasive plant species may require similar natural conditions, but that the invasive plant species seem more dependent and influenced by anthropogenic disturbance factors.

关键词： Anthropogenic disturbance Biodiversity Native species Biological invasions Distribution Himalayas

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Improvements after mod Quad and triangle tilt revision surgical procedures in obstetric brachial plexus palsy

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World Journal of Orthopedics 2016年第11期7卷 752-757页

作者： Rahul K Nath chandra Somasundaram Texas Nerve and Paralysis Institute

AIM To compare outcomes of our revision surgical operations in obstetric brachial plexus palsy(OBPP) patients to results of conventional operative procedures at other institutions. METHODS We analyzed our OBPP data and identified 10 female and 10 male children aged 2.0 to 11.8 years(average age 6.5 years), who had prior conventional surgical therapies at other clinics. Of the 20 patients, 18 undergone triangle tilt, 2 had only mod Quad. Among 18 patients, 8 had only triangle tilt and 10 had also mod Quad as revision surgeries with us. We analyzed the anatomical improvements and functional modified Mallet statistically before and after a year post-revision *** Pre-revision surgery average modified Mallet score was 12.0 ± 1.5. This functional score was greatly improved to 18 ± 2.3(P < 0.0001) at least one-year after revision surgical procedures. Radiological scores(PHHA and glenoid version) were also improved significantly to 31.9 ± 13.6(P < 0.001),-16.3 ± 11(P < 0.0002), at least one-year after triangle tilt procedure. Their mean pretriangle tilt(yet after other surgeon's surgeries) PHHA, glenoid version and SHEAR were 14.6 ± 21.7,-31.6 ± 19.3 and 16.1 ± 14.7 *** We demonstrate here, mod Quad and triangle tilt assuccessful revision surgical procedures in 20 OBPP patients, who had other surgical treatments at other clinics before presenting to us for further treatment.

关键词： Revision surgery Obstetric brachial plexus palsy Shoulder movements Joint incongruity Upper limb

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Exploring the potential of artificial intelligence techniques in prediction of the removal efficiency of vortex tube silt ejector

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International Journal of Sediment Research 2023年第4期38卷 615-627页

作者： Sanjeev Kumar chandra Shekhar Prasad Ojha Nand Kumar Tiwari Subodh Ranjan Department of Civil Engineering Indian Institute of Technology Department of Civil Engineering National Institute of Technology

A vortex tube silt ejector is a curative hydraulic structure used to remove sediment deposits from canals and is recognized as one of the most efficient substitutes for physically removing canal sediment. The spatially varied flow in the channel and the rotational flow behavior in the tube make the silt removal process complex. It is even harder to accurately predict the silt removal efficiency by traditional models accurately. However, artificial intelligence(AI) and machine learning approaches have emerged as robust substitutes for studying complex processes. Therefore, this research makes use of AI approaches; support vector machine(SVM), random forest(RF), random tree(RT), and multivariate adaptive regression spline(MARS) to compute the vortex tube silt ejection efficiency using the laboratory data sets. The outcomes of the artificial intelligence(AI)-based techniques also were compared with traditional models. It was found that the RT model(root mean square error, RMSE = 2.165, Nash Sutcliffe efficiency, NSE = 0.98) outperforms the other applied approaches which had relatively more significant result errors. The sensitivity analysis of the process depicts the extraction ratio as the key parameter in the computation of vortex tube silt ejector removal efficiency. The findings of the AI-based approaches discussed in the current study might be helpful for hydraulic engineers as well as researchers in the assessment of the removal efficiency of vortex tube silt ejectors.

关键词： Vortex tube silt ejector Support vector machine Random forest Random tree Multivariate adaptive regression spline

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Independent principal component analysis for simulation of soil water content and bulk density in a Canadian Watershed

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International Soil and Water Conservation Research 2016年第3期4卷 151-158页

作者： Alaba Boluwade chandra A.Madramootoo Department of Bioresource Engineering McDonald Campus of McGill University 21111 Lakeshore RoadSte-Anne-De-BellevueQuebec H9X3V9Canada

Accurate characterization of soil properties such as soil water content(SWC)and bulk density(BD)is vital for hydrologic processes and thus,it is importance to estimateθ(water content)andρ(soil bulk density)among other soil surface parameters involved in water retention and infiltration,runoff generation and water erosion,*** spatial estimation of these soil properties are important in guiding agricultural management *** soil properties vary both in space and time and are ***,it is important to find an efficient and robust technique to simulate spatially correlated *** such as principal component analysis(PCA)and independent component analysis(ICA)can be used for the joint simulations of spatially correlated variables,but they are not without their *** study applied a variant of PCA called independent principal component analysis(IPCA)that combines the strengths of both PCA and ICA for spatial simulation of SWC and BD using the soil data set from an 11 km^(2) Castor watershed in southern Quebec,*** checks using the histograms and cumulative distribution function(cdf)both raw and back transformed simulations show good ***,the results from this study has potential in characterization of water content variability and bulk density variation for precision agriculture.

关键词： Spatial variability Soil properties Agricultural decision-making Independent principal component analysis

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Effect of process parameter on the flowability of nanocrystalline CoNiCrAlY powder synthesized by mechanical milling

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Particuology 2024年第9期92卷 210-223页

作者： Annadaa Shankara Dash Indranil Manna Deepa Devapal Sharad chandra Sharma Jyotsna Dutta Majumdar School of Nanoscience and Technology IIT KharagpurWest BengalIndia BIT Mesra RanchiJharkhandIndia Department of Metallurgical and Materials Engineering IIT KharagpurWest BengalIndia Vikram Sarabhai Space Centre ThiruvanthapuramKeralaIndia

The present study concerns understanding the effect of process parameters on the characteristics and flowability of nanocrystalline CoNiCrAlY powder synthesized by mechanical *** milling has been conducted in a planetary ball mill with tungsten carbide(WC)ball,with ball to powder ratio of 10:1 at 300 rpm speed,using 1%stearic acid and toluene as process control agent(PCA)with time varying from 10 h to 36 *** synthesized nanocrystalline powder were characterized by Scanning Electron Microscopy,X-ray Diffraction technique,X-ray Photoelectron Spectroscopy,and Differential Scanning ***,flowability in terms of Hausner ratio was assessed by Tap Density *** particle size of the powder was found to decrease from 33μm to 22μm after 10 h of milling and further increases to 43μm and 38μm after 25 and 36 h of milling,respectively,in stearic acid ***,in toluene medium particle size continuously decreases from 33μm to 9.7μm with increasing milling *** particle morphology changes from spherical to platelet shape at low milling hours in both of the *** 25 h of milling,the shape of the particles is nearly spherical for stearic acid and irregular for toluene used as a *** size was found to decrease with increasing milling time from 147 nm to 7.7 nm and to 6.4 nm in stearic acid and toluene media,*** was presence ofγ,γʹ,β,hcp-Co,Al_(2)O_(3)and AlOOH phases on the powder particles milled in both the *** measured Hausner ratio of the powders was found to vary from 1.18 to 1.32 in stearic acid medium,and was found to increase with increasing milling *** the other hand,in toluene media flowability decreases(Hausner ratio increases from 1.33 to 1.44)with increasing milling time.

关键词： Mechanical milling Microstructure Process control agent(PCA) CoNiCrAlY Toluene Stearic acid Flowability

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Global Production Sharing and Sino-US Trade Relations

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China & World Economy 2009年第3期17卷 39-56页

作者： Prema.chandra Athukorala Nobuaki Yamashita Research School of Pacific and Asian Studies Australian National University School of Economics and Finance La Trobe University

This paper examines Sino-US trade relations, focusing on the ongoing process of global production sharing, involving splitting of the production process into discrete activities that are then allocated across countries, and the resulting trade complementarities between the two countries in world manufacturing trade. The results suggest that the Sino--US trade imbalance is basically a structural phenomenon resulting from the pivotal role played by China as the final assembly centre in East Asia-centered global production networks.

关键词： global production sharing Sino-US trade trade balance

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A review on perovskite solar cells (PSCs),materials and applications

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Journal of Materiomics 2021年第5期7卷 940-956页

作者： N.Suresh Kumar K.chandra Babu Naidu Department of Physics JNTUA College of EngineeringAnantapuramu515002A.PIndia Dept.of Physics GITAM Deemed to be UniversityBangalore562163KarnatakaIndia

In recent years,the perovskite solar cells have gained much attention because of their ever-increasing power conversion efficiency(PCE),simple solution fabrication process,flyable,light-weight wearable and deployable for ultra-lightweight space and low-cost materials constituents *** the last few years,the efficiency of perovskite solar cells has surpassed 25%due to high-quality perovskite-film accomplished through low-temperature synthesis techniques along with developing suitable interface and ***,the stability of perovskite solar cells has attracted much well-deserved *** this article we have focused on recent progress of the perovskite solar cells regarding their crystallinity,morphology and synthesis ***,demonstrated different layers such as electron transport-layers(ETLs),hole transport-layers(HTLs)and buffer-layers utilized in perovskite solar-cells,considering their band gap,carrier mobility,transmittance *** of various tin(Sn),carbon and polymer-based perovskite solar cells and their potential of commercialization feasibility has also been discussed.

关键词： Perovskite solar-cells Power conversion efficiency Hole transport layer Electron transport layer Buffer layer Photovoltaic devices

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Electroosmotic oscillatory flow of micropolar fluid in microchannels:application to dynamics of blood flow in microfluidic devices

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Applied Mathematics and Mechanics(English Edition) 2014年第6期35卷 749-766页

作者： J.C.MISRA S.chandra G.C.SHIT P.K.KUNDU Department of Mathematics Institute of Technical Education and ResearchSiksha O Anusandhan University Department of Mathematics Jadavpur University

The electroosmotic flow of a micropolar fluid in a microchannel bounded by two parallel porous plates undergoing periodic vibration is studied. The equations for conservation of linear and angular momentums and Gauss＇s law of charge distribution are solved within the framework of the Debye-Hückel approximation. The fluid velocity and microrotation are assumed to depend linearly on the Reynolds number. The study shows that the amplitude of microrotation is highly sensitive to the changes in the magnitude of the suction velocity and the width of the microchannel. An increase in the micropolar parameter gives rise to a decrease in the amplitude of microrotation. Numerical estimates reveal that the microrotation of the suspended microelements in blood also plays an important role in controlling the electro-osmotically actuated flow dynamics in microbio-fluidic devices.

关键词： blood flow electrohydrodynamic effect microfluidics channel flow

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Comparative study on machinability improvement in hard turning using coated and uncoated carbide inserts： part II modeling, multi-response optimization, tool life, and economic aspects

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Advances in Manufacturing 2018年第2期6卷 155-175页

作者： Ramanuj Kumar Ashok Kumar Sahoo Purna.chandra Mishra Rabin Kumar Das School of Mechanical Engineering Kalinga Institute of Industrial Technology Bhubaneswar-24 Odisha India

The present study focused on mathematical modeling, multi response optimization, tool life, and eco- nomical analysis in finish hard turning of AISI D2 steel （（55 4- 1） HRC） using CVD-coated carbide （TiN/TiCN/ A1203） and uncoated carbide inserts under dry environ- mental conditions. Regression methodology and the grey relational approach were implemented for modeling and multi-response optimization, respectively. Comparative economic statistics were carried out for both inserts, and the adequacy of the correlation model was verified. The experimental and predicted values for all responses were very close to each other, implying the significance of the model and indicating that the correlation coefficients were close to unity. The optimal parametric combinations for A1203 coated carbide were dl-fl-v2 （depth of cut = 0.1 mm, feed = 0.04 mm/r and cutting speed = 108 m/min）, and those for the uncoated tool were dl-（0.1 mm）-fl （0.04 mm/r）-vl （63 rn/min）. The observed tool life for the coated carbide insert was 15 times higher than that for the uncoated carbide insert, considering flank wear criteria of 0.3 mm. The chip volume after machining for the coated carbide insert was 26.14 times higher than that of the uncoated carbide insert and could be better utilized for higher material removal rate. Abrasion, diffusion, notch- ing, chipping, and built-up edge have been observed to be the principal wear mechanisms for tool life estimation. Use of the coated carbide tool reduced machining costs by about 3.55 times compared to the use of the uncoated carbide insert, and provided economic benefits in hard turning.

关键词： Machinability Hard turning Regression Grey relational analysis Tool life Economic analysis

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Plant Identification Using Fitness-Based Position Update in Whale Optimization Algorithm

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Computers, Materials & Continua 2022年第6期71卷 4719-4736页

作者： Ayman Altameem Sandeep Kumar Ramesh chandra Poonia Abdul Khader Jilani Saudagar Department of Computer Science College of Applied StudiesKing Saud UniversityRiyadh11495Saudi Arabia Department of Computer Science and Engineering CHRIST(Deemed to be University)Bangalore560074India Department of Computer Science CHRIST(Deemed to be University)Bangalore560029India Information Systems Department Imam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia

Since the beginning of time,humans have relied on plants for food,energy,and *** are recognized by leaf,flower,or fruit and linked to their suitable *** methods are used to extract and select traits that are helpful in identifying a *** plant leaf image categorization,each plant is assigned a label according to its *** purpose of classifying plant leaf images is to enable farmers to recognize plants,leading to the management of plants in several *** study aims to present a modified whale optimization algorithm and categorizes plant leaf images into *** modified algorithm works on different sets of plant *** proposed algorithm examines several benchmark functions with adequate *** ten plant leaf images,this classification method was *** proposed model calculates precision,recall,F-measurement,and accuracy for ten different plant leaf image datasets and compares these parameters with other existing *** on experimental data,it is observed that the accuracy of the proposed method outperforms the accuracy of different algorithms under consideration and improves accuracy by 5%.

关键词： Bag-of-features feature optimization plant leaf classification swarm intelligence nature-inspired algorithm

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