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Determination of Fluoride in Various Samples Using a Fluoride Selective Electrode

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Adaptive Linear Quadratic Regulator for Continuous-Time Systems With Uncertain Dynamics

Journal of Analytical Sciences, Methods and Instrumentation 2020年第4期

作者： Kamal Shaiyad Miya vinay kumar jha

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IEEE/CAA Journal of Automatica Sinica 2020年第3期7卷 833-841页

作者： Sumit kumar jha Shubhendu Bhasin IEEE Department of Electronics and Communication Engineering Motilal Nehru National Institute of Technology AllahabadPrayagraj-211004India Department of Electrical Engineering Indian Institute of Technology DelhiNew Delhi-110016India

In this paper, adaptive linear quadratic regulator(LQR) is proposed for continuous-time systems with uncertain dynamics. The dynamic state-feedback controller uses inputoutput data along the system trajectory to continuously adapt and converge to the optimal controller. The result differs from previous results in that the adaptive optimal controller is designed without the knowledge of the system dynamics and an initial stabilizing policy. Further, the controller is updated continuously using input-output data, as opposed to the commonly used switched/intermittent updates which can potentially lead to stability issues. An online state derivative estimator facilitates the design of a model-free controller. Gradient-based update laws are developed for online estimation of the optimal gain. Uniform exponential stability of the closed-loop system is established using the Lyapunov-based analysis, and a simulation example is provided to validate the theoretical contribution.

关键词： Adaptive optimal control continuous policy update linear quadratic regulator uncertain system dynamics

Temporal patterns of storage and flux of N and P in young Teak plantations of tropical moist deciduous forest,India

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Journal of Forestry Research 2014年第1期25卷 75-86页

作者： Kaushalendra kumar jha Technical Forestry Indian Institute of Forest Management

Teak （Tectona grandis Linn. f.） ranks among the top five tropical hardwood species and is being promoted for use in plantations in its non-native range due to its high economic value. However, there is a general lack of data on ecosystem functioning of teak plantations. We aimed at understanding storage and flux of nutrients related to young plantations of teak. Cycling of nitrogen （N） and phosphorus （P） in a chronosequence of plantations （1, 5, 11, 18, 24 and 30 years） was studied in the Moist Deciduous Forest Region of North India with the objective of investigating the nutrient cycling pattern at younger age since the current trend of harvesting age of the species in several tropical countries is being drastically reduced for quick return from this high value crop. Standing state, nutrient uptake, nutrient return and nutrient retransloca-tion in these plantations were estimated by tree harvesting and chemical analysis methods. The range of total standing nutrient across all these plantations was 20.3 to 586.6 kg？ha-1 for N and 5.3 to 208.8 kg？ha-1 for P. Net uptake of N ranged from 19.4 to 88.9 kg？ha-1？a-1 and P from 3.8 to 18.1 kg？ha-1？a-1. Retranslocation of N and P among all the stands ranged from 8.7 to 48.0 kg？ha-1？a-1 and 0.01 to 3.5 kg？ha-1？a-1, respectively. Range of total nutrient return was 25.8 to 91.3 kg？ha-1？a-1 for N and 2.7 to 10.1 kg？ha-1？a-1 for P. N and P use efficiency was between 107.4 and 192.5 g dry organic matter （OM） g-1N, and 551.9 and 841.1 g OM g-1P, respec-tively. The turnover time ranged from 2.04-13.17 years for N and be-tween 2.40-22.66 years for P. Quantity of N and P in the soil nutrient pool ranged from 2566.8 to 4426.8 kg？ha-1 and 372 to 520 kg？ha-1, re-spectively. Storage and flux of components in different plant parts of different aged plantations were assessed and depicted in compartment models. Percentage storage in soil, litter and vegetation ranged from 82% to 99%, 0.6% to 2.4% and 0.5% to 15% for N, respectively, and from

关键词： nutrient uptake standing state return turnover time nutrient use efficiency compartment model harvest loss Tectona grandis

Biomass production and carbon balance in two hybrid poplar(Populus euramericana)plantations raised with and without agriculture in southern France

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Journal of Forestry Research 2018年第6期29卷 1689-1701页

作者： Kaushalendra kumar jha UMR Systems Institute Nationale de la Recherche Agronomique2 place Pierre Viala34060 MontpellierFrance Technical Forestry Indian Institute of Forest ManagementBhopalIndia

Poplar is useful in different climates for bioenergy production and carbon sequestration when planted as a single species or in agroforestry. Europe has large areas potentially suitable for poplar forestry and a bioenergy policy that would encourage poplar forestry. In this study I estimated biomass production and carbon sequestration in poplar monoculture plantation and poplar-wheat agroforestry, in the Mediterranean region of France. A single-tree harvesting method was used to estimate biomass and an empirical conversion factor was adopted to calculate sequestered carbon. Total biomass was higher in agroforestry trees(1223 kg tree) than in monoculture plantation trees(1102 kg tree).Aboveground and belowground biomass distributions were similar in both cases(89 and 88% aboveground, and 11 and12% belowground, respectively in agroforestry and monoculture). The partitioning of total biomass in an agroforestry tree in leaves, branch, and trunk(aboveground), and fine roots, medium roots, coarse roots and underground stem(belowground) was 1,22,and 77,and 6,9, 44 and 40%,respectively. Except for branch and trunk, all other compartments were similarly distributed in a monoculture *** of C was higher in agroforestry trees(612 kg tree)than in monoculture trees(512 kg tree). In contrast, C storage on a per hectare basis was lower in agroforestry(85 Mg ha) than in monoculture(105 Mg ha) due to the lower density of trees per hectare in agroforestry(139 trees in agroforestry vs 204 trees in monoculture). On a per hectare basis, soil C stocks pattern were similar to per tree stocking:They were higher in agroforestry at 330 Mg hathan in monoculture 304 Mg ha. Higher C accumulation by agroforestry has a direct management implication in the sense that expanding agroforestry into agriculture production areas with short rotation and fast growing trees like poplar would encourage quicker and greater C sequestration. This could simultaneously fulfil the requirement of bioenergy

关键词： Populus euramericana Wood volume and density Root:shoot ratio Vegetation and soil carbon System efficiency

Carbon storage and sequestration rate assessment and allometric model development in young teak plantations of tropical moist deciduous forest, India

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Journal of Forestry Research 2015年第3期26卷 589-604页

作者： Kaushalendra kumar jha Technical Forestry Indian Institute of Forest ManagementPO Box No. 357 Nehru Nagar Bhopal 462 003 MP India

Carbon （C） sequestration through plantations is one of the important mitigation measures for rising levels of carbon dioxide and other greenhouse gases in the atmosphere. This study aimed to assess C stocks and their sequestration rate, and to develop allometric models for estimation of C stocking in age-series young teak （Tectona grandis） planta- tions （1, 5, 11, 18, 24 and 30 years） by using biomass and productivity estimation and regression, respectively. These plantations were raised in tropical moist deciduous forests of Kumaun Himalayan tarai. Total C stocks estimated for these plantations were 1.6, 15.8, 35.4, 39.0, 61.5 and 73.2 Mg ha-1, respectively. Aboveground and belowground C storage in- creased with increasing plantation age; however, the range of their percentage contribution showed little variation （87.8-88.2 and 11.7-12.7 %, respectively）, The rate of C sequestration for these respective plantations was 1.06, 6.95, 5.46, 5.42, 3.39 and 5.37 Mg ha-1 a-1. Forty percent of the aboveground annual storage was retained in the tree while 60 % was released in the form of foliage, twigs, and fruit litter. In the case of total （tree） annual production, 43 % was retained while 57 % was released as litter including root. C stock, C sequestration rate, accumulation ratio （1.4-18.1）, root：shoot C ratio （0.61--0.13） and production efficiency （0.01-0.18） were comparable to some previous reports for other species and forests. These data could be useful in deciding the harvesting age for young teak with respect to C storage and sequestrationrate. Four allometric models using linear regression equations were developed between biomass （twice the C stock） and diameter, girth, and height of the tree at different ages. The diameter model was found more suitable for C stock predic- tion in similar areas.

关键词： Age series Biomass Carbon budget DBH Productivity Production ratios Regression equations -Tectona grandis

Secure approach to sharing digitized medical data in a cloud environment

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Data Science and Management 2024年第2期7卷 108-118页

作者： Kukatlapalli Pradeep kumar Boppuru Rudra Prathap Michael Moses Thiruthuvanathan Hari Murthy vinay jha Pillai Department of Computer Science and Engineering CHRIST(Deemed to be University)Bengaluru560074India Department of Electronics and Communication Engineering CHRIST(Deemed to be University)Bengaluru560074India

Without proper security mechanisms, medical records stored electronically can be accessed more easily than physical files. Patient health information is scattered throughout the hospital environment, including laboratories, pharmacies, and daily medical status reports. The electronic format of medical reports ensures that all information is available in a single place. However, it is difficult to store and manage large amounts of data. Dedicated servers and a data center are needed to store and manage patient data. However, self-managed data centers are expensive for hospitals. Storing data in a cloud is a cheaper alternative. The advantage of storing data in a cloud is that it can be retrieved anywhere and anytime using any device connected to the Internet. Therefore, doctors can easily access the medical history of a patient and diagnose diseases according to the context. It also helps prescribe the correct medicine to a patient in an appropriate way. The systematic storage of medical records could help reduce medical errors in hospitals. The challenge is to store medical records on a third-party cloud server while addressing privacy and security concerns. These servers are often semi-trusted. Thus, sensitive medical information must be protected. Open access to records and modifications performed on the information in those records may even cause patient fatalities. Patient-centric health-record security is a major concern. End-to-end file encryption before outsourcing data to a third-party cloud server ensures security. This paper presents a method that is a combination of the advanced encryption standard and the elliptical curve Diffie-Hellman method designed to increase the efficiency of medical record security for users. Comparisons of existing and proposed techniques are presented at the end of the article, with a focus on the analyzing the security approaches between the elliptic curve and secret-sharing methods. This study aims to provide a high level of s

关键词： Electronic medical records Cloud computing Data privacy Attribute-based encryption Authentication

Assessing foundation behaviour under complex loading near tunnels

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Journal of Mountain Science 2024年第10期21卷 3503-3520页

作者： Piyush kumar vinay Bhushan CHAUHAN Aayush kumar Civil Engineering Department Madan Mohan Malaviya University of TechnologyGorakhpur 273010India

The stability of strip footings subjected to eccentrically inclined loads is critical for reliable foundation *** study investigates the effect of a circular unlined tunnel in a rock mass on the ultimate bearing capacity(UBC)of a foundation with width B under inclined and eccentric *** finite element limit analysis was employed to evaluate the reduction in UBC of the footing resting above a *** examined critical parameters include normalized load eccentricity(e/B),load inclination(β),and horizontal and vertical distances of the tunnel from the foundation(P/B and Q/B,respectively),along with rock mass *** results reveal that for e/B≥0.25 and β≤60°,the reduction coefficient,R_(c)≥0.90,suggesting that the presence of a tunnel has a minimal impact on the load-bearing capacity of the footing,with failure primarily governed by load eccentricity and ***,potential failure mechanisms are explored,showing that at lower e/B,higher β,and lower Q/B,the tunnel significantly affects footing's failure ***,at higher e/B and lower β,failure is due to rotational effects of footing,regardless of the tunnel's *** predict the Rc more accurately,due to the time-consuming nature of direct calculations,both MLR and ANN models were *** MLR model provided a baseline for comparison,while the ANN model,with a coefficient of determination(R2)of 0.98,demonstrated superior accuracy compared to the R2=0.96 of *** both approaches ensured robust and efficient predictions of *** Rc does not directly provide the reduced UBC of footing due to presence of tunnel,the study introduced bearing capacity factor(Nc)to enable direct calculation of the reduced UBC of *** findings offer theoretical guidelines for preliminary design and provide practitioners with an effective tool for evaluating UBC reduction in complex loading scenarios involving tunnels.

关键词： Unlined tunnel Shallow foundation FELA Rock Mass ANN MLR

Synergistic effect of hybrid Himalayan Nettle/Bauhinia-vahlii fibers on physico-mechanical and sliding wear properties of epoxy composites

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Defence Technology（防务技术） 2020年第4期16卷 762-776页

作者： Sandeep kumar KKSMer Brijesh Gangil vinay kumar Patel Department of Mechanical Engineering S.O.E.T.H.N.B.Garhwal UniversitySrinagar-Garhwal246174UttarakhandIndia Department of Mechanical Engineering Govind Ballabh Pant Institute of Engineering and Technology GhurdauriPauri Garhwal246001UttarakhandIndia

The cellulosic bast fibers are recognized as a justifiable and biodegradable substitute for producing moderate strength polymer composite materials because of their characteristics of renewability,ecofriendliness,and higher specific *** the aim of this research work is to fabricate Himalayan bast fibers(Nettle fiber(NF)/bauhinia vahlii fiber(BF)) based mono/hybrid epoxy composites at varying weight percentage of 2-6 wt% and evaluate the physical(void fraction and water absorption),mechanical(tensile strength,flexural strength,hardness) and sliding wear properties of as-fabricated *** 6 wt% NBF reinforced composites exhibited higher mechanical properties as compared to NF and BF composites with tensile strength of 34.04 MPa,flexural strength of 42.45 MPa,and hardness of 37.01 Hv *** influence of various control factors(sliding velocity,NF/BF/NBF contents,normal load and sliding distance) on specific sliding wear rate of composites was evaluated by Taguchi(three factors at three levels) experimental design and the percentage contribution of these selected parameters on sliding wear performance was examined by Analysis of variance(ANOVA).The sliding wear property of as-developed composites was found to be greatly influenced by sliding velocity and the wear resistance was observed to be improved with the NF/BF/NBF *** wear mechanism of the as-fabricated composites has been elucidated by scanning electron microscopy *** research outcomes demonstrated that the hybridization of Bauhinia vahlii fiber with Nettle fiber led to improve the mechanical and wear properties of epoxy composites.

关键词： Natural fiber Physical properties Mechanical properties Wear properties Taguchi analysis

Thermodynamic behaviour of Rashba quantum dot in the presence of magnetic field

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Chinese Physics B 2016年第5期25卷 262-267页

作者： Sukirti Gumber Manoj kumar Pradip kumar jha Man Mohan Department of Physics & Astrophysics University of Delhi Department of Physics DDU College University of Delhi

The thermodynamic properties of an In Sb quantum dot have been investigated in the presence of Rashba spin–orbit interaction and a static magnetic field. The energy spectrum and wave-functions for the system are obtained by solving the Schrodinger wave-equation analytically. These energy levels are employed to calculate the specific heat, entropy,magnetization and susceptibility of the quantum dot system using canonical formalism. It is observed that the system is susceptible to maximum heat absorption at a particular value of magnetic field which depends on the Rashba coupling parameter as well as the temperature. The variation of specific heat shows a Schottky-like anomaly in the low temperature limit and rapidly converges to the value of 2kB with the further increase in temperature. The entropy of the quantum dot is found to be inversely proportional to the magnetic field but has a direct variation with temperature. The substantial effect of Rashba spin–orbit interaction on the magnetic properties of quantum dot is observed at low values of magnetic field and temperature.

关键词： quantum dot Rashba spin–orbit interaction thermal and magnetic properties