KUNDAN KUMAR - Academia.edu (original) (raw)

Papers by KUNDAN KUMAR

Lecture notes in electrical engineering, Nov 3, 2018

Nowadays, security from unauthorized humans (intruders) and fire/flame is one of the essential co... more Nowadays, security from unauthorized humans (intruders) and fire/flame is one of the essential concerns especially in industries, banks, airports, railway stations, and other restricted areas. Therefore, we introduce an Electronic Security System (ESS). The ESS provides the attentive message from the flame as well as intruders. The proposed system generally consists of three devices, namely, PIR sensors, MSP430, and GSM. The flames and intruder are recognized by PIR. These activities are feeding to HMM, which are synthesized by wavelet transform. When there is an action that occurs within the sensor range, then the signal from the sensor is processed by bi-orthogonal wavelet transform and then feed to HMMs. The detection of intruder and flame is updated according to the HMM producing the highest probability. After that, the alert message is sent to authorize person using GSM.

We consider the problem proposed by Thales Nederland at the SWI 2012 meeting. Thales Nederland is... more We consider the problem proposed by Thales Nederland at the SWI 2012 meeting. Thales Nederland is the Dutch branch of the international Thales Group. The company specializes in designing and producing professional electronics for defence and security applications, such as radar and communication systems. Moreover, Thales Nederland acts as a local point of contact for the complete portfolio of the Thales Group. During the SWI 2012 meeting, on behalf of Thales Nederland, Dr. Maurits de Graaf posed several questions regarding the maximization of the lifetime of a wireless sensor network. We addressed these questions during the workshop and our most significant results are summarized as follows: We have proven that this lifetime maximization problem, even under the most simple constraints, is NP-complete, so it is not possible to find an algorithm that gives the optimal solution within polynomial time. Furthermore, we have constructed a counterexample to illustrate that the heuristic currently used by Thales can be asymptotically at least log n times worse than the optimal solution. Moreover, we have developed a new heuristic and have illustrated with several numerical examples that it performs better than the heuristic currently used by Thales. Finally, we have formulated the problem as a linear programming problem and used this to quantify how far the heuristic used by Thales is from being optimal.

Processes

The rise in population, urbanization, and industrial developments have led to a substantial incre... more The rise in population, urbanization, and industrial developments have led to a substantial increase in waste generation and energy demand, posing significant challenges for waste management as well as energy conservation and production. Bioenergy conversions have been merged as advanced, sustainable, and integrated solutions for these issues, encompassing energy generation and waste upcycling of different types of organic waste. Municipal solid waste (MSW) and agricultural residues (AR) are two main resources for bioenergy conversions. Bioenergy production involves feedstock deconstruction and the conversion of platform chemicals to energy products. This review provides a detailed overview of waste sources, biofuel, and bioelectricity production from fermentation and microbial fuel cell (MFC) technology, and their economic and environmental perspectives. Fermentation plays a critical role in liquid biofuel production, while MFCs demonstrate promising potential for simultaneous prod...

$Research paper thumbnail of Formal upscaling and numerical validation of fractured flow models for Richards′ equation$

In this work, we consider a mathematical model for describing flow in an unsaturated porous mediu... more In this work, we consider a mathematical model for describing flow in an unsaturated porous medium containing a fracture. Both the flow in the fracture as well as in the matrix blocks are governed by Richards’ equation coupled by natural transmission conditions. Using formal asymptotics, we derive upscaled models as the vanishing limit of ε, the ratio of the width and length of the fracture. Our results show that the ratio of porosities and permeabilities in the fracture to matrix determine, to the leading order of approximation, the appropriate effective model. In these models the fracture is a lower dimensional object for which different transversally averaged models are derived depending on the ratio of the porosities and permeabilities of the fracture and respective matrix blocks. We obtain a catalogue of effective models which are validated by numerical computations.

The incorporation of number of unit cells in EBG arrangement produces two major side effects on t... more The incorporation of number of unit cells in EBG arrangement produces two major side effects on the performance of patch antenna. First one is parasitic loading, this causes multi resonance in antenna hence obtains some enhancement in antenna band width. Second one is cavity effect, this reflects some of energy from EBG toward antenna which results in reducing bandwidth. Present paper, rectangular microstrip patch antenna is surrounded by number of EBG rows is designed; and the results of proposed antenna with a conventional patch antenna is presented comparatively.

Shifting cultivation policies: balancing environmental and social sustainability, 2017

This chapter examines the processes through which hill slopes customarily used by ethnic communit... more This chapter examines the processes through which hill slopes customarily used by ethnic communities in Odisha for shifting cultivation were taken over by the state as forest lands or revenue wastelands through deliberate policies aimed at bringing shifting cultivation to an end. The chapter covers both the colonial and post-colonial situations in Odisha that led to denial of the legitimacy of shifting cultivation, and ends with the impacts of these processes on shifting cultivators and landscapes. The failure to recognize the rights of shifting cultivation communities in the state to the hill slopes they traditionally cultivated has had serious implications on their access to land and livelihoods.

arXiv: Numerical Analysis, 2018

In this work, we study the parallel-in-time iterative solution of coupled flow and geomechanics i... more In this work, we study the parallel-in-time iterative solution of coupled flow and geomechanics in porous media, modelled by a two-field formulation of the Biot's equations. In particular, we propose a new version of the fixed stress splitting method, which has been widely used as solution method of these problems. This new approach forgets about the sequential nature of the temporal variable and considers the time direction as a further direction for parallelization. We present a rigorous convergence analysis of the method and a numerical experiment to demonstrate the robust behaviour of the algorithm.

Phase field modelling for dissolution and precipitation Iuliu Sorin Pop, Manuela Bastidas, Carina... more Phase field modelling for dissolution and precipitation Iuliu Sorin Pop, Manuela Bastidas, Carina Bringedal, Florin Adrian Radu and Lars vonWolff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Efficient simulation of linear and nonlinear poroelasticity F. A. Radu, J. Both, M. Borregales, K. Kumar, J. M. Nordbotten and E. Storvik4

Journal of Applied Hematology, 2021

BACKGROUND: Automated hematology analyzers effectively reduce turnaround time and generates scatt... more BACKGROUND: Automated hematology analyzers effectively reduce turnaround time and generates scattergrams which can be used to screen for different hematological conditions. AIMS: We wish to study the scattergrams generated by the Sysmex XN-series analyzer for confirmed cases of hematological malignancies and evaluate for the specific patterns to these malignancies. METHODS: Two hundred and ninety-one newly diagnosed cases of various hematological malignancies were included in the study. All these cases were diagnosed and classified in accordance with flow cytometry, bone marrow morphological study, immunohistochemistry, and molecular studies. Forty-eight cases of leukemoid reaction were also included in the study. We retrieved the scattergrams and complete blood count data of all these cases which were processed in the Sysmex XN-analyzer before their diagnosis. Along with scattergrams, the peripheral blood smear findings of all the cases were extracted too. The scattergram patterns in the white blood cell differential (WDF) and white cell nucleated region (WNR) channels were evaluated and correlated with their peripheral blood smear findings. RESULTS: All the scattergrams in the WDF and WNR channels were studied. Patterns seen in acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) were striking and distinctly separate. After correlating with the peripheral smear and immunophenotyping, AML patterns were subtyped by the French American British classification. Acute promyelocytic leukemia as well as different phases of chronic myeloid leukemia had unique patterns. Scattergram patterns of ALL had minute difference with that of chronic lymphoproliferative disorder. CONCLUSION: In high-volume laboratories, the patterns on Sysmex XN-series analyzer scattergrams can be used as a valuable aid for suspecting and triaging cases of hematological malignancies.

Quarterly of Applied Mathematics, 2019

We study the solution of the system of equations describing the dynamical evolution of spontaneou... more We study the solution of the system of equations describing the dynamical evolution of spontaneous ruptures generated in a prestressed elastic-gravitational deforming body and governed by rate and state friction laws. We propose an iterative coupling scheme based on a weak formulation with nonlinear interior boundary conditions, both for continuous time and with implicit discretization (backward Euler) in time. We regularize the problem by introducing viscosity. This guarantees the convergence of the scheme for solutions of the regularized problems in both cases. We also make precise the conditions on the relevant coefficients for convergence to hold.

Computers & Mathematics with Applications, 2020

The paper is concerned with guaranteed a posteriori error estimates for a class of evolutionary p... more The paper is concerned with guaranteed a posteriori error estimates for a class of evolutionary problems related to poroelastic media governed by the quasi-static linear Biot equations. The system is decoupled employing the fixed-stress split scheme, which leads to a semi-discrete system solved iteratively. The error bounds are derived by combining a posteriori estimates for contractive mappings with those of the functional type for elliptic partial differential equations. The estimates are applicable for any approximation in the admissible functional space and are independent of the discretization method. They are fully computable, do not contain mesh dependent constants, and provide reliable global estimates of the error measured in the energy norm. Moreover, they suggest efficient error indicators for the distribution of local errors, which can be used in adaptive procedures.

$Research paper thumbnail of Formal upscaling and numerical validation of unsaturated flow models in fractured porous media$

Journal of Computational Physics, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

International Journal of Computer Trends and Technology, 2019

A prior research done indicates that there is various challenges farmers face including unpredict... more A prior research done indicates that there is various challenges farmers face including unpredictable weather conditions affecting farmers' yields, slow flow of information from the agronomist and meteo Rwanda to the farmers, regionalized weather information, data provided by meteo is hard for farmers to interpret.This project was sponsored by UNDP-Rwanda and organised by Rwanda Meteorology Agency. The aim of this system is to help in fast communication between Rwanda Meteorology Agency, agronomists, famers' facilitators and farmers in meaningful way. The researchers used qualitative methods by conducting an interview with the meteo, agronomist, and farmers. An observation was also used to get first-hand information on the flow of communication betweenmeteo, agronomists, volunteers, farmer facilitators and farmers. Existing Communication was Analyzed andProposed Effiective Kubero Communication Model, which allow faster communication between stakeholders.An Innovative approaches Agile methodology was used to develop a pilot project. A prototype was designed to deliver timely climate related information and predictions to address pressing needs of farmers in climate disaster prone areas. Where farmers will be periodically accessing of clear weather prediction via USSD, together with agronomists' suggestion, so that they can plan a head and a prototype was distributed betweenmeteoRwanda, agronomist, volunteers and farmers for their feedback.Farmers Smart Technology is a three one App, which has Android App, USSD farmer App and Meteo Web App. Agronomist will use Android App to access provincial weather forecast data to provide suggestion to famers. Agronomist can send emergency alert to famers' facilitators. Farmers can retrieve weather forecast data along with agronomist's suggestion in meaningful way using USSD App. Farmers can provide feedback on weather prediction in yes, no or maybe which can help meteorology Agency to improve their prediction. Volunteer will also use USSD App to feed temperatures and rainfall of the day. This Volunteers' data will be accessed by Rwanda Meteorology Agency using Meteo Web App for their approval.The feature that the system provides makes this proposed system an easy to use.

International Journal of Current Microbiology and Applied Sciences, 2019

Computational Geosciences, 2018

We consider a non-linear extension of Biot's model for poromechanics, wherein both the fluid flow... more We consider a non-linear extension of Biot's model for poromechanics, wherein both the fluid flow and mechanical deformation are allowed to be non-linear. We perform an implicit discretization in time (backward Euler) and propose two iterative schemes for solving the non-linear problems appearing within each time step: a splitting algorithm extending the undrained split and fixed stress methods to non-linear problems, and a monolithic L-scheme. The convergence of both schemes is shown rigorously. Illustrative numerical examples are presented to confirm the applicability of the schemes and validate the theoretical results. Index terms-Biot's model L-schemes MFEM convergence analysis coupled problems poromechanics

Computers & Mathematics with Applications, 2019

Please cite this article in press as: M. Borregales, et al., A partially parallel-in-time fixed-s... more Please cite this article in press as: M. Borregales, et al., A partially parallel-in-time fixed-stress splitting method for Biot's consolidation model, Computers and Mathematics with Applications (2018),

Transport in Porous Media, 2018

We study a heuristic, core-scale model for the transport of polymer particles in a two phase (oil... more We study a heuristic, core-scale model for the transport of polymer particles in a two phase (oil and water) porous medium. We are motivated by recent experimental observations which report increased oil recovery when polymers are injected after the initial waterflood. The recovery mechanism is believed to be microscopic diversion of the flow, where injected particles can accumulate in narrow pore throats and clog it, in a process known as a log-jamming effect. The blockage of the narrow pore channels lead to a microscopic diversion of the water flow, causing a redistribution of the local pressure, which again can lead to the mobilization of trapped oil, enhancing its recovery. Our objective herein is to develop a core-scale model that is consistent with the observed production profiles. We show that previously obtained experimental results can be qualitatively explained by a simple two-phase flow model with an additional transport equation

International Journal of Horticultural Science, 2000

On the basis of a six-year experiment a method was elaborated for forcing and off-seasons growing... more On the basis of a six-year experiment a method was elaborated for forcing and off-seasons growing of tulips, narcissus and gladioli under frameless plastic cover. The advantages of this cheap energy-saving method are manifested in an improved quality of flowers and essentially in the earlier flowering. With this method mostly first-class flowers can be obtained immediately after the season of forcing in heated constructions with plastic cover, and anticipated outdoor flowering. The possibilities of applying the method are studied on further ornamental plant species (other bulbous plants, Paeonia lactiflora, annual ornamentals).