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Vaccination is seen as a weapon that not only profits an individual to fight the deadly SARS-CoV-2 virus but also helps in building herd immunity for the general public, There are a lot of individuals who are keen and willing to get inoculated by the Covid-19 vaccine and return back to their normal life, However, there is some public who still are unwilling for the vaccination due to vaccine hesitancy, And even after vaccination(one dose), there may be cases of breakthrough infeclions with mild symptoms, Unwillingness for vaccination and breakthrough infections are now very important aspects of this ongoing epidemic amid the vaccination process that needs to be challenged by responsible stakeholders, Thus, we will first formulate an ordinary differential equation CODE) model consisting of willing and unwilling (for vaccination) population along with breakthrough infection, We will then extend ODE model to a queueing model that accounts for the movement of willing and non-willing susceptible individuals as well, The governing equations are formed and the transition rates from one stage to another are taken to follow an exponential distribution, The transient state probabilities of the model are acquired by applying the matrix method and thereafter Runge-Kutta 4th order method is employed to attain various performance indices, The parameters are estimated for our system based on the standard nonlinear least-squares method using the real data of the vaccinated Cone dose) population for India between the time period of 5 March 202 I to 3 July 2021, We would first aim to study the impact of this system on the basic reproduction number pt The sensitivity analysis of p' is done to recognize the important estimated parameters which may help in controlling the epidemic, Then the impact of the unwillingness and breakthrough infections directly helping in transmission of the infection amid the vaccination process is shown by uncertainty analysis using the technique of PRCC and contour plots. Numerical analysis is also provided to certify the queueing model. [ABSTRACT FROM AUTHOR]

The accurate determination of factor of safety is important to find out the stability of slopes. Out of the many factors which are responsible for slope failure in hilly areas continuous rainfall, particularly, is one of the major important factor responsible for triggering landslide. Slope is an exposed ground surface that stands at an angle with the horizontal. In this study, a part of the hill of Haflong, the head quarter of Dima Hasao district in the state of Assam, India are chosen. Two types of transient analysis i.e., uncoupled analysis and coupled analysis were carried out. The coupled analysis considers the deformation of the soil surface with time when rain water passes through the soil mass. Three slope angles 30°, 45° and 90° were considered for both the case. The results shows that the factor of safety decreases with increase in the period of rainfall and slope angle, whereas the factor of safety increases slightly during coupled analysis which is due to the combined effect of deformation and seepage. [ABSTRACT FROM AUTHOR]

• A thermal–hydraulic model for an SFR SG is created using the FLOWNEX code. • The model uses fixed meshes with regime-specific flow and heat transfer correlations. • Steady-state predictions of the model are validated by inter-code comparison. • Transient predictions of the model are validated against ETEC and SGTF experiments. The steam generator (SG) is an important component in sodium-cooled fast reactors (SFRs). It transfers the heat from sodium systems to the balance of plant (BOP), producing steam for electricity production. Any disturbances originating from the BOP propagate to the nuclear systems through SG. Hence, it is especially important to model and predict the thermal–hydraulic behavior of SG during such transients. Towards this, a thermal–hydraulic model of SG of a typical medium-sized SFR has been developed using general-purpose system simulation code – FLOWNEX. Usually, the moving boundary method is used to model SGs as it involves phase change and multiple heat transfer regimes. However, in the current model, the fixed mesh approach, generally used for modeling pipelines, single-phase heat exchangers, etc. in plant dynamic codes, has been used to model SGs. In this paper, the modeling details and the solution procedures used in the FLOWNEX are discussed in detail. The steady-state results of the model developed have been compared with the results from in-house code DESOPT. The results were in good agreement at various power levels as well as in off-design conditions. The transient performance of the model has been validated against an in-house experiment carried out in Steam Generator Test Facility (SGTF), IGCAR, India, and a steam generator shutdown experiment carried out in Energy Technology Engineering Center (ETEC), Santa Susana Field Laboratory (SSFL), USA. The transient results were also in good agreement, thereby increasing the confidence level of the predictions. The model developed will be integrated to plant dynamic codes containing other system models and will be used to carry out system-level simulations in the future. [ABSTRACT FROM AUTHOR]

• FPGA based EMT simulation framework for the power distribution network is presented. • Conjugate-gradient based electrical network solver is implemented. • Simulation framework is validated for the Jail substation of Guwahati city, India. • Results are compared with the MATLAB based EMT implementation. The electrical power distribution network (PDN) is in the transition phase due to the integration of distributed energy resources (DERs). Therefore, an accurate and efficient modeling and simulation platform is the need of the hour to determine the dynamic behavior of the PDN. The recent computational hardware, such as GPU, FPGA, etc. enables new simulation paradigm and develop a more realistic platform in the form of system emulators. In this paper, an FPGA based electromagnetic transient (EMT) simulation framework for the PDN is presented. Conjugate-gradient (CG) based electrical network solver is implemented in the proposed framework, and a test case is analyzed for Jail substation of Guwahati city, India, to validate the simulation environment. It has been compared with the MATLAB based implementation for verifying its accuracy. The proposed EMT simulator is approximately 12.5 times faster as compared to its MATLAB implementation and exhibits good accuracy as well. [ABSTRACT FROM AUTHOR]

Abstract: Thermal performance of Earth Air Tunnel Heat Exchanger (EATHE) under transient operating conditions has been evaluated for predominantly hot and dry climate of Ajmer (India) using experimental and Computational Fluid Dynamics modeling. Effects of time duration of continuous operation, thermal conductivity of soil pipe diameter and flow velocity on thermal performance of EATHE under transient conditions have been analyzed. Results show that the transient thermal performance of EATHE is significantly dependent on thermal conductivity of the soil and duration of its continuous operation. The analyzed cases have shown the range of derating to be as minimal as 0% to as high as 64%, which if ignored while designing may lead to poor performance of EATHE. Study reveals that the effect of pipe diameter due to prolonged use of EATHE system on its thermal performance is least in case of soil with higher value of thermal conductivity. Results show that the increase in flow velocity leads to deterioration in thermal performance of EATHE system. Under steady state condition, drop of 18.8°C in air temperature is obtained, whereas, under transient conditions cooling of air reduces from 18.7°C to 16.6°C for soil thermal conductivity of 0.52Wm−1 K−1, after 24h of continuous operation. [Copyright &y& Elsevier]

Abstract: Thermal performance of earth air tunnel heat exchanger (EATHE) under transient operating conditions has been evaluated for predominantly hot and dry climate of Ajmer (India) using experimental and computational fluid dynamics modeling. Effect of time duration of continuous operation and thermal conductivity of soil on thermal performance of EATHE under transient conditions has been analyzed. Results show that the transient thermal performance of EATHE is significantly dependent on thermal conductivity of the soil and duration of its continuous operation. Under steady state condition, a drop of 18.8°C is obtained in air passing through EATHE having 0.1m diameter and 60m length, at 5ms−1 flow velocity, whereas, the transient analysis shows that for soil having thermal conductivity of 0.52Wm−1 K−1, the cooling of air reduces from 18.7°C to 16.6°C, after 24h of continuous operation. Change in cooling effect after 24h of operation for soil thermal conductivity of 2.0Wm−1 K−1 and 4.0Wm−1 K−1, reduced from 18.8°C to 18.5°C and 18.8°C to 18.7°C respectively. The analyzed cases have shown the range of derating to be as minimal as 0% to as high as 64%, which if ignored while designing may lead to poor performance of earth air heat exchangers. [Copyright &y& Elsevier]

Abstract: Thermal performance of Earth Air Tunnel Heat Exchanger (EATHE) under transient operating conditions in winter season has been evaluated for predominantly hot and dry climate of Ajmer (India) using experimental and Computational Fluid Dynamics (CFD) modeling. Effect of time duration of continuous operation and thermal conductivity of soil on thermal performance of EATHE under transient conditions has been analyzed. Results show that the transient thermal performance of EATHE is significantly dependent on thermal conductivity of the soil and duration of its continuous operation. Under steady state condition, a rise of 19.6°C is obtained in air passing through EATHE having 0.1m diameter and 60m length, at 5m/s flow velocity, whereas, the transient analysis shows that for soil having thermal conductivity of 0.52Wm−1 K−1, the heating of air reduces from 19.4°C to 17.2°C, after 24h of continuous operation. Heating effect after 24h of operation for soil thermal conductivity of 2.0Wm−1 K−1 and 4.0Wm−1 K−1, reduced from 19.6°C to 19.2°C and 19.6°C to 19.5°C, respectively. The analyzed cases have shown the range of derating to be as minimal as 0% to as high as 64%, which if ignored while designing may lead to poor performance of earth air heat exchangers. [Copyright &y& Elsevier]

Incorporating insulation material in the building envelope is one of the simple yet effective passive techniques aimed at mitigating the energy consumption in buildings. The development and utilization of sustainable materials with heat insulating capacity as an alternative to synthetic insulations is a promising path towards reduced carbon footprint of buildings. The insulation potential of straw, an agricultural waste, in the context of the wide-ranging climate of India is the focus of the current work. Cooling and/or heating load analysis over 24 h of a representative summer and winter day is performed through transient numerical analysis for five climatic zones of India. Three building envelope configurations possible with retrofitting straw insulation (placed on the outside or inside or equally on either side) over existing walls/roof are compared. Four different thicknesses (10, 20, 30 and 40 cm) of the straw insulation are considered for analysis. Recommendations of envelope configuration with insulation are proposed based on energy and cost savings for the different climatic zones. Overall, the case of straw insulation split on either side performs the best. Energy savings in the range of 67–96% is achievable with the addition of just 10 cm thick straw across different climatic zones. The work also presents a comparison of the straw envelope performance against different types of envelopes based on sustainable materials found in literature. • Transient cooling/heating loads estimated for summer and winter days for five climatic zones of India. • The insulating potential of straw, a cheap and abundantly available sustainable material, is studied. • Three envelope configurations made of concrete-straw-plaster are considered. • Energy and cost savings are presented for straw thicknesses of 10, 20, 30 and 40 cm. • Energy savings vary in the range 67–96% and 88–100% for 10 and 40 cm cases, respectively. [ABSTRACT FROM AUTHOR]