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Journal of Forestry Research 2016年第5期27卷 1055-1065页

作者： Chittaranjan das Naba kumar Mondal Department of Environmental Science The University of Burdwan

We studied leaf litter fall, decomposition and nutrient release patterns of Shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf litter. Annual litterfall varied from 13.40 ± 2.56 t ha-1 a-1 for S. robusta to 11.03 ± 3.72 t ha-1 a-1 for T. grandis and the decay constant （k） of decomposed leaf litter was distinctly higher for T. grandis （2.70 ± 0.50 a-1） compared to S. robusta （2.41 ±0.30 a-1）. Biomass loss was positively correlated with the initial litter C, WSC, C/N and ash content in S. robusta and N, P and K concentration for T. grandis. Biomass was negatively correlated with lignin and L/N ratio for S. robusta and L, WSC, L/N and C/N ratio for T. grandis （P 〈 0.01）. Nutrient use efficiency （NUE） and nutrient accumulation index （NAI） of S. robusta was higher than for T. grandis. The retranslocation of bioelements from senescent leaves ranked as P 〉 N 〉 K. Annual N, P and K input to soil through litterfall differed significantly between the two species in the following order： N〉K^P. S. robusta was superior in terms of K and P return and T. grandis was superior in terms of N return. The two tree species showed a similar patterns of nutrient release （K 〉 P 〉 N） during decomposition of their leaf *** of N, K and P were the primary limiting nutrients returned to soil through litterfall with important roles in soil fertility and forest productivity.

关键词： Decay constant Lignin Litterfall Nutrientreturn Decomposition Nutrient use efficiency

Deep Neural Network and Pseudo Relevance Feedback Based Query Expansion

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Computers, Materials & Continua 2022年第5期71卷 3557-3570页

作者： Abhishek kumar Shukla Sujoy das Department of Mathematics Bio-Informatics and Computer ApplicationsMaulana Azad National Institute of Technology BhopalBhopalMadhya Pradesh462003India

The neural network has attracted researchers immensely in the last couple of years due to its wide applications in various areas such as Data mining,Natural language processing,Image processing,and Information retrieval *** embedding has been applied by many researchers for Information retrieval *** this paper word embedding-based skip-gram model has been developed for the query expansion *** terms are obtained from the top“k”initially retrieved documents using the Pseudo relevance feedback model and then they are trained using the skip-gram model to find the expansion terms for the user *** performance of the model based on mean average precision is *** proposed model compares with other existing *** improvement of 6.61%,6.93%,and 9.07%on MAP value is observed compare to the Original query,BM25 model,and query expansion with the Chi-Square model *** proposed model also retrieves 84,25,and 81 additional relevant documents compare to the original query,query expansion with Chi-Square model,and BM25 model respectively and thus improves the recall value *** per query analysis reveals that the proposed model performs well in 30,36,and 30 queries compare to the original query,query expansion with Chi-square model,and BM25 model respectively.

关键词： Information retrieval query expansion word embedding neural network deep neural network

Soft chemistry based sponge-like indium tin oxide a prospective component of photoanode for solar cell application

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Frontiers of Materials Science 2015年第2期9卷 126-131页

作者： Prasanta kumar BISWAS Nilanjana das Department of Physics Indian Institute of Technology Roorkee Roorkee-247 667 Uttarakhand India

Previously we reported the synthesis of novel organic-inorganic compo- site indium tin oxide （ITO） foam precursor leading to the formation of ＂sponge-like＂ ITO by burning away the organics, This newly made sponge-like ITO possesses relatively high electrical conductivity due to phonon confinement with reasonable pore structure and may have potential application as functional materials in semiconducting dye absorbing layer in dye-sensitized solar cell （DSSC） and also as the receptor of electrons injected from the quantum dots （QDs） of organic-inorganic hybrid QD based solar cell. This report is a short review of ＂sponge-like＂ ITO described as a lecture note on its future use as an alternative new prospective material for photoanode of solar cell in the domain of sustainable energy,

关键词： sponge-like indium tin oxide (ITO) sol-gel ITO nanoporous ITO smokelike ITO film indium nitrate-PVA foam

Strain induced changes in performance of strained-Si/strained-Si1-yGey/relaxed-Si1-xGex MOSFETs and circuits for digital applications

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Journal of Central South University 2017年第6期24卷 1233-1244页

作者： kumar Subindu kumari Amrita das Mukul K Department of Electronics Engineering Indian School of MinesDhanbad 826004India

Growing a silicon(Si) layer on top of stacked Si-germanium(Ge) compressive layer can introduce a tensile strain on the former, resulting in superior device characteristics. Such a structure can be used for high performance complementary metal-oxide-semiconductor(CMOS) circuits. Down scaling metal-oxide-semiconductor field-effect transistors(MOSFETs) into the deep submicron/nanometer regime forces the source(S) and drain(D) series resistance to become comparable with the channel resistance and thus it cannot be neglected. Owing to the persisting technological importance of strained Si devices, in this work, we propose a multi-iterative technique for evaluating the performance of strained-Si/strained-Si_(1-y)Ge_y/relaxed-Si_(1-x)Ge_x MOSFETs and its related circuits in the presence of S/D series resistance, leading to the development of a simulator that can faithfully plot the performance of the device and related digital circuits. The impact of strain on device/circuit performance is also investigated with emphasis on metal gate and high-k dielectric materials.

关键词： complementary metal-oxide-semiconductor (CMOS) high-k dielectric material inverter metal-oxide-semiconductor field-effect transistors (MOSFETs) SiGe series resistance strain

Identification of parameter to assess cracking resistance of asphalt mixtures subjected to aging and moisture conditioning

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第2期9卷 293-304页

作者： Bhaskar Pratim das Anjan kumar Siddagangaiah Department of Civil Engineering Indian Institute of Technology GuwahatiGuiuahati 781039India

This study comprehensively evaluated different parameters based on tensile strength testing to assess the cracking resistance of asphalt mixtures subjected to aging and moisture *** this purpose,two sources of aggregates were selected to produce hot and warm mix asphalt *** mixtures were subjected to short term and long term aging,three levels of moisture conditioning(freeze thaw cycles),and tested at two temperatures(15℃and 25℃).The load-displacement data was used to determine the fracture work density,fracture energy,toughness index,cracking resistance index,cracking tolerance index,and rate dependent cracking *** was noticed that moisture conditioning increased the variability of the different *** cracking tolerance index and rate dependent cracking index parameter had a much higher coefficient of variation(Co V)with a maximum value close to 50%.Indirect tensile strength,fracture energy,and fracture work density appropriately captured the effect of moisture on cracking resistance of *** cracking resistance index,cracking tolerance index,and rate dependent cracking index increased with an increase in the moisture conditioning *** Statistical analysis showed that tensile strength,fracture work density,and fracture energy were significantly influenced by different aging and moisture conditions *** energy showed better association with fatigue life of asphalt mixtures subjected to three freeze-thaw cycles compared to tensile ***,the fatigue life prediction models showed that both indirect tensile strength and fracture energy significantly influence the fatigue life of asphalt mixtures subjected to aging and moisture conditioning.

关键词： Cracking resistance Aging Moisture Warm mix additive Fatigue life

Phytochemical Profiling and Bioactivity of A Mangrove Plant,Sonneratia apetala,from Odisha Coast of India

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Chinese Journal of Integrative Medicine 2015年第4期21卷 274-285页

作者： Jayanta kumar Patra Swagat kumar das Hrudayanath Thatoi Department of Biotechnology College of Engineering and TechnologyBiju Patnaik University of Technology School of Biotechnology Yeungnam University

Objective： To test the antioxidant, antidiabetic, anticancer and antibacterial activities along with phytochemicals of Sonneratia apetala Buch.-Ham. Methods： The antibacterial activity was determined by agar well diffusion method. The antioxidant activity was determined by standard assay. The antidiabetic activity was evaluated by α-glucosidase inhibition assay and in vivo anticancer property was determined against Ehrlich ascites carcinoma （EAC） cells in Swiss Albino mice. Further partial characterization of the methanol extracts was carried out by thin layer chromatography, high performance liquid chromatography, 1H nuclear magnetic resonance spectroscopy and Fourier transform-infra red spectrum spectral analysis. Results： Four solvent extracts （acetone, ethanol, methanol and aqueous） of leaf and bark possess strong antioxidant properties. In vivo anticancer activity of methanol extract leaf indicated positive activity showing 34% inhibition against EAC cells in Swiss Albino mice. All extracts exhibited a-glucosidase inhibitory activity in a dose-dependent manner indicating presence of promising antidiabetic properties. The extracts possess strong antibacterial activity against the selected pathogenic bacteria （minimal inhibitory concentration ranging from 1.25-5.00 mg/mL）. The partial characterization of the methanol extracts of leaf and bark revealed the presence of phenolics as the lead compound responsible for studied bioactivities of the plant extracts. Conclusion： Sonneratia apetala extracts have potent antibacterial, antioxidant, antidiabetic and anticancer properties which can be further exploited for its pharmaceutical applications.

关键词： bioactive compounds chromatography Ehrlich ascites carcinoma mangrove Sonneratia apetala

Estimation of carbon sequestration in reclaimed coalmine degraded land dominated by Albizia lebbeck, Dalbergia sissoo and Bambusa arundinacea plantation： a case study from Jharia Coalfields, India

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International Journal of Coal Science & Technology 2016年第2期3卷 246-266页

作者： Rimi das Subodh kumar Maiti Ecological Restoration Laboratory Department of Environmental Science and Engineering (Centre of Mining Environment) Indian School of Mines Dhanbad Jharkhand 826 004 India

Reclaimed mined lands provide an excellent opportunity to sequester carbon and combat global warming. Carbon sequestration on reclaimed sites depend on age of reclamation, composition of species, geomining conditions （soil characteristics） and prevailing climate. The aims of the present study were to calculate carbon （C）--stock of biomass of 4 years old plantation （dominated by Albizia lebbeck, Dalbergia sissoo and Bambusa arundinacea）, understorey vegetation and litter, soil organic carbon in reclaimed minesoil （RMS） and compare with reference forest site. Allometric equation was used for the estimation of biomass C stock and found 13.0 Mg C ha i （A lebbeck 7.8 Mg C ha-I, D sissoo 3.5 Mg C ha-l and B. arundincea 1.2 Mg C ha-l）, while stock of understorey vegetation was 0.98 Mg C ha-~. In RMS, C stock was 16.3 Mg C ha-1, out of which inorganic C contributed 1.7 g kg-l （8 % of total soil C）, Coal C 8.7 g kg^-1 （43 % of total soil C） and biogenic C 9.8 g kg^-1 （49 % of total soil C）. Total C stock in reclaimed site was calculated as 30.3 Mg C ha^-1（equivalent to 111 Mg CO2 ha-b. The study concluded that （i） coal C is responsible for overestimation of C stock in RMS （ii） Maximun C stock stored in aboveground biomass component and （iii） reclaimed mined lands will take approximately 17 years to reach the level of C stock of reference forest site in dry tropical climate.

关键词： Coal Opencast mining Reclaimed mine soils Biomass carbon Carbon sequestration Carbon stock

A Survey on Modelling and Compensation for Hysteresis in High Speed Nanopositioning of AFMs:Observation and Future Recommendation

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International Journal of Automation and computing 2020年第4期17卷 479-501页

作者： Maniza ArminPriyo Nath RoySajal kumar das Department of Mechatronics Engineering Rajshahi University of Engineering&TechnologyRajshahi 6204Bangladesh Department of Mechatronics Engineering Khulna University of Engineering&TechnologyKhulna 9203Bangladesh

This paper surveys the recent advances on the modeling and control of hysteresis of piezoelectric actuators(PTAs)in the context of high precision applications of atomic force microscopes(AFMs).The current states,findings,and outcomes on hysteresis modeling and control in terms of achievable bandwidth and accuracy are discussed in *** challenges and the scope of possible research are presented to pave the way to video rate atomic force microscopy.

关键词： Hysteresisno nlinearities piezoelectric actuator smart actuatoratomic force microscope

Correlation among extinction efficiency and other parameters in an aggregate dust model

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Research in Astronomy and Astrophysics 2017年第11期17卷 95-112页

作者： Tanuj kumar Dhar Himadri Sekhar das Department of Physics Assam University Silchar 788011 India

We study the extinction properties of highly porous Ballistic Cluster-Cluster Aggregate dust aggregates in a wide range of complex refractive indices （1.4 ≤ n 〈 2.0, 0.001 ≤ k 〈 1.0） and wavelengths （0.11 μm 〈 A 〈 3.4 μm）. An attempt has been made for the first time to investigate the correlation among extinction efficiency （Qext）, composition of dust aggregates （n, k）, wavelength of radiation （A） and size parameter of the monomers （x）. If k is fixed at any value between 0.001 and 1.0, Qext increases with increase of n from 1.4 to 2.0. Qext and n are correlated via linear regression when the cluster size is small, whereas the correlation is quadratic at moderate and higher sizes of the cluster. This feature is observed at all wavelengths （ultraviolet to optical to infrared）. We also find that the variation of Qext with n is very small when A is high. When n is fixed at any value between 1.4 and 2.0, it is observed that Qext and k are correlated via a polynomial regression equation （of degree 1, 2, 3 or 4）, where the degree of the equation depends on the cluster size, n and A. The correlation is linear for small size and quadratic/cubic/quartic for moderate and higher sizes. We have also found that Qext and x are correlated via a polynomial regression （of degree 3, 4 or 5） for all values of n. The degree of regression is found to be n and k-dependent. The set of relations obtained from our work can be used to model interstellar extinction for dust aggregates in a wide range of wavelengths and complex refractive indices.

关键词： light scattering -- ISM: dust extinction

Comparative investigation towards machinability improvement in hard turning using coated and uncoated carbide inserts： part Iexperimental investigation

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Advances in Manufacturing 2018年第1期6卷 52-70页

作者： Ramanuj kumar Ashok kumar Sahoo Purna Chandra Mishra Rabin kumar das School of Mechanical Engineering Kalinga Institute of Industrial Technology BhubaneswarOdisha 751024 India

The investigation of low cost uncoated andcoated carbide insert in the hard turning of hardened AISID2 steel （≥55 HRC） will definitely open up a new arena asan economical alternative suitable to industrial machiningsectors. Thus, this paper reports the comparative machin-ability assessment for the hard turning of AISI D2 steel（（55 ± 1） HRC） by coated and uncoated carbide insert in adry environment. Micro hardness and abrasion tests werecarried out to assess resistance capability against wear. Theabove test results confirmed the greater wear resistanceability of AIaO3 coated carbide insert over uncoated car-bide. Based on the extensive investigation of comparativemachinability, the coated carbide insert （TiN-TiCN-A12O3）outperformed the uncoated carbide insert with regard tosurface roughness, flank wear, chip-tool interface temper-ature, and chip morphology. Abrasion and diffusion wereobserved as the principal tool wear mechanisms in theinvestigated range. The uncoated carbide failed completelydue to the severe chipping and quick dulling of the cuttingedge, which led to its unsuitability for machining hardenedsteel.

关键词： Coated and uncoated carbide Hard turning Machinability Flank wear Surface roughness Chipmorphology Cutting temperature