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Quantification by allometric equations of carbon sequestered by Tectona grandis in different agroforestry systems

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Journal of Forestry Research 2013年第4期24卷 699-702页

作者： Avinash jain S.A.Ansari Tropical Forest Research Institute

Non destructive methods for quantification of carbon seques- tration in tropical trees are inadequately developed. We described a stan- dardized method for estimating carbon stock in teak （Tectona grandis Linn. F.）. We developed linear allometric equations using girth at breast height （GBH）, height and age to quantify above ground biomass （AGB）. We used AGB to estimate carbon stock for teak trees of different age groups （1.5, 3.5, 7.5, 13.5, 18.5 and 23.5 years）. The regression equation with GBH, y = 3.174x - 21.27, r2=0.898 （p 〈0.01）, was found precise and convenient due to the difficulty in determination of height and age in dense natural forests of teak. The equation was evaluated in teak agroforestry systems that included Triticum aestivum （wheat）, Cicer arietinum （gram）, Withania somnifera （ashwagandha）,

关键词： Tectona grandis agroforestry system allometric equation carbon sequestration above ground biomass

Three distinct global estimates of historical land-cover change and land-use conversions for over 200 years

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Frontiers of Earth Science 2012年第2期6卷 122-139页

作者： Prasanth MEIYAPPAN Atul K. jain Department of Atmospheric Sciences University of Illinois Urbana IL 61801 USA

Earth＇s land cover has been extensively transformed over time due to both human activities and natural causes. Previous global studies have focused on developing spatial and temporal patterns of dominant human land-use activities （e.g., cropland, pastureland, urban land, wood harvest）. Process-based modeling studies adopt different strategies to estimate the changes in land cover by using these land-use data sets in combination with a potential vegetation map, and subsequently use this information for impact assessments. However, due to unaccounted changes in land cover （resulting from both indirect anthropogenic and natural causes）, heterogeneity in land-use/cover （LUC） conversions among grid cells, even for the same land use activity, and uncertainty associated with potential vegetation mapping and historical estimates of human land use result in land cover estimates that are substantially different compared to results acquired from remote sensing observations. Here, we present a method to implicitly account for the differences arising from these uncertainties in order to provide historical estimates of land cover that are consistent with satellite estimates for recent years. Due to uncertainty in historical agricultural land use, we use three widely accepted global estimates of cropland and pastureland in combination with common wood harvest and urban land data sets to generate three distinct estimates of historical land-cover change and underlying LUC conversions. Hence, these distinct historical reconstructions offer a wide range of plausible regional estimates of uncertainty and the extent to which different ecosystems have undergone changes. The annual land cover maps and LUC conversion maps are reported at 0.5°×0.5° resolution and describe the area of 28 land- cover types and respective underlying land-use transitions. The reconstructed data sets are relevant for studies addressing the impact of land-cover change on biogeo- physics, biogeochemistry, water cy

关键词： historical land use land-cover change land-use conversions deforestation HYDE Moderate Resolu-tion Imaging Spectroradiometer (MODIS)

Relationship between CME dynamics and solar flare plasma

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Research in Astronomy and Astrophysics 2010年第5期10卷 473-483页

作者： Rajmal jain Malini Aggarwal Pradeep Kulkarni Physical Research Laboratory (Deptartment of Space Government of India) Navrangpura Ahmedabad - 380 009 India Deptartment of Physics Z. B. Patil College North Maharashtra University

The relationship between the velocity of CMEs and the plasma temperature of the associated X-ray solar flares is investigated. The velocity of CMEs increases with plasma temperature （R = 0.82） and photon index below the break energy （R = 0.60） of X-ray flares. The heating of the coronal plasma appears to be significant with respect to the kinetics of a CME from the reconnection region where the flare also occurs. We propose that the initiation and velocity of CMEs perhaps depend upon the dominant process of conversion of the magnetic field energy of the active region to heating/accelerating the coronal plasma in the reconnected loops. Results show that a flare and the associated CME are two components of one energy release system, perhaps, magnetic field free energy.

关键词： Sun: corona — Sun: coronal mass ejections (CMEs) — Sun: flares

Secure and Optimal LOADng Routing for IoT with Composite RoutingMetric

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Computers, Materials & Continua 2023年第1期74卷 655-669页

作者： Divya Sharma Sanjay jain Vivek Maik Department of Electronics and Communication New Horizon College of EngineeringBengaluru560103India CMR Institute of Technology Bengaluru560037India Department of Electronics and Communication SRM Institute of Science and TechnologyKattankulathurChennai603203India

Security is the one of the major challenges for routing the data between the source and destination in an Internet of Things(IoT)*** overcome this challenge,a secure Lightweight On-demand Ad hoc Distancevector—Next Generation(LOADng)Routing Protocol is proposed in this *** the LOADng protocol is the second version of Ad Hoc On-Demand Distance Vector(AODV)protocol,it retains most of the basic functionality and characteristics of *** the route discovery process,the cyclic shift transposition algorithm(CSTA)is used to encrypt the control packets of the LOADng protocol to improve its *** approach only derives transposition and substitution without product cipher with respect to input *** this,for choosing the best probable path between the source and destination,routing metrics such as link quality Indicator(LQI),hop count(HC)and queue length(QL)are included in the control *** data is then securely sent using CSTA using the optimal secure path *** Results depict that the proposed secure and optimal LOADng(SO-LOADng)using CSTA encryption obtains better throughput,delivery ratio encryption time and decryption time than the existing state-ofart approaches.

关键词： IoT LOADng CSTA link quality indicator queue length

Correction of CT Burst Array Errors in the Generalized-Lee-RT Spaces

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Acta Mathematica Sinica,English Series 2010年第8期26卷 1475-1484页

作者： Sapna jain K.P.SHUM Department of Mathematics University of Delhi Department of Mathematics The University of Hong Kong

In [jain, S.： Array codes in the generalized-Lee-RT-pseudo-metric （the GLRTP-metric）, to appear in Algebra Colloq.], jain introduced a new pseudo-metric on the space Matm×s（Zq）, the module space of all m × s matrices with entries from the finite ring Zq, generalized the classical Lee metric [Lee, C. Y.： Some properties of non-binary error correcting codes. IEEE Trans. Inform. Theory, IT-4, 77- 82 （1958）] and array RT-metric [Rosenbloom, M. Y., Tsfasman, M. A.： Codes for m-metric. Prob. Inf. Transm., 33, 45-52 （1997）] and named this pseudo-metric as the Generalized-Lee-RT-Pseudo-Metric （or the GLRTP-Metric）. In this paper, we obtain some lower bounds for two-dimensional array codes correcting CT burst array errors [jain, S.： CT bursts from classical to array coding. Discrete Math., 308-309, 1489-1499 （2008）] with weight constraints under the GLRTP-metric.

关键词： Linear array codes Lee metric RT metric CT burst array errors

Random and Periodic Sleep Schedules for Target Detection in Sensor Networks

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Journal of Computer Science & Technology 2008年第3期23卷 343-354页

作者： Vaishali P.Sadaphal Bijendra N.jain Tata Research Development and Design Centre(TRDDC) PuneIndia Department of Computer Science and Engineering Indian Institute of TechnologyDelhiNew DelhiIndia

We study random and periodic sleep schedules from the point of view of delay in detecting the target. We consider sleep schedules in which a sensor in ＂inactive＂ mode wakes up either randomly or periodically to detect presence of the target within its vicinity resulting into two sleep schedules：（a） random wake-up schedule, and （b） periodic wake-up schedule respectively. Specifically, we analyse and obtain for the random wake-up schedule the expected delay in detection, and the delay, such that with probability P, the delay is less than the computed value. For the periodic wake-up schedule we show that there exists an upper bound on the delay. Further we compute the average value of delay. We have shown that the theoretically computed averages and the upper bounds on the delay match with the simulation results for the random wake-up and periodic wake-up schedules.

关键词： sleep schedule energy conservation target detection

Orbital X-ray modulation study of three supergiant HMXBs

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Research in Astronomy and Astrophysics 2009年第12期9卷 1303-1316页

作者： Chetana jain Biswajit Paul Anjan Dutta Department of Physics and Astrophysics University of Delhi Raman Research Institute SadashivnagarC.V.Raman Avenue

We present the orbital X-ray modulation study of three high mass X-ray binary systems, IGR J18027-2016, IGR J18483-0311 and IGR J16318-4848, using data obtained with RXTE-ASM, Swift-BAT and INTEGRAL-ISGRI. Using the long term light curves of the eclipsing HMXB IGR J18027-2016, obtained with Swift-BAT in the energy range 15-50keV and INTEGRAL-ISGRI in the energy range 22-40 keV, we have determined three new mid eclipse times. The newly determined mid eclipse times together with the known values were used to derive an accurate value of the orbital period of 4.5693（4） d at MJD 52168 and an upper limit of 3.9（1.2）×10^-7d d-1 on the period derivative. We have also accurately determined an orbital period of 18.5482（88）d for the intermediate system IGR J 18483-0311, which displays an unusual behavior and shares many properties with the known SFXTs and persistent supergiant systems. This is a transient source and the outbursts occur intermittently at intervals of 18.55 d. Similarly, in the third supergiant system, IGR J16318-4848, we have found that the outbursts are separated by intervals of 80 d or its multiples, suggesting a possible orbital period.

关键词： X-ray: neutron stars -- X-ray binaries: individual

A methodological approach for weighting factors in land suitability assessment: a tool for facilitating spatial planning

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Journal of Mountain Science 2020年第3期17卷 724-739页

作者： Neetu KAPOOR Minakshi jain Vijay Kumar BANSAL Department of Architecture National Institute of Technology HamirpurHP 177005India School of Planning and Architecture VijayawadaAP 520008India Department of Civil Engineering National Institute of Technology HamirpurHP 177005India

The increasing demand for infrastructural facilities in hill areas needs efficient spatial planning at the local level through land suitability assessment,which is influenced by a number of factors. There has been little systematic empirical work for identification and evaluation of the factors affecting spatial planning decisions in hill areas. The present study focuses on identifying the critical factors for land suitability assessment at the local level in hill areas and determining their percentage influence, which has been done in two stages. In the first stage, the comprehensive list of 21 factors from the reported literature was prepared which was further condensed to the critical factors. In the second stage, the percentage influence of the critical factors was calculated by analyzing the experts’ opinions collected through a questionnaire survey. Analytic Hierarchy Process(AHP) was used for the analysis of the questionnaire for weighting the critical factors. The slope was identified with the highest weight followed by aspect, surface runoff, elevation, and vegetation,whereas groundwater table, existing utilities,accessibility, soil type, and land use have comparatively less weights. The results of the study were used for the identification of locations for builtup facilities of an educational campus located in hill areas of Himachal Pradesh, India.

关键词： Factor identification Hill areas Analytic hierarchy process India Weighted overlay

Optimal band structure for thermoelectrics with realistic scattering and bands

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npj Computational Materials 2021年第1期7卷 388-396页

作者： Junsoo Park Yi Xia Vidvuds Ozoliņš Anubhav jain Energy Technologies Area Lawrence Berkeley National LaboratoryBerkeleyCAUSA Department of Materials Science and Engineering Northwestern UniversityEvanstonILUSA Department of Applied Physics Yale UniversityNew HavenCTUSA Energy Sciences Institute Yale UniversityWest HavenCTUSA

Understanding how to optimize electronic band structures for thermoelectrics is a topic of long-standing interest in the *** models have been limited to simplified bands and/or scattering *** this study,we apply more rigorous scattering treatments to more realistic model band structures—upward-parabolic bands that inflect to an inverted-parabolic behavior—including cases of multiple *** contrast to common descriptors(e.g.,quality factor and complexity factor),the degree to which multiple pockets improve thermoelectric performance is bounded by interband scattering and the relative shapes of the *** establish that extremely anisotropic“flat-and-dispersive”bands,although best-performing in theory,may not represent a promising design strategy in ***,we determine optimum bandwidth,dependent on temperature and lattice thermal conductivity,from perfect transport cutoffs that can in theory significantly boost zT beyond the values attainable through intrinsic band structures *** analysis should be widely useful as the thermoelectric research community eyes zT>3.

关键词： bands parabolic apply