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Intro -- Title Page -- Copyright -- Dedication -- Contents -- Preface -- Part I: Crisis -- 1. Solitary -- 2. Uncertain Winds -- 3. Reluctant Resignation -- 4. Elephant -- 5. Guilty Until Proven Innocent -- Part II: Karma Yoga -- 6. A Dark Diwali -- 7. Hot Pickle at Harvard -- 8. The Firm -- 9. Chicago -- 10. Unity in Diversity -- 11. Let My Country Awake -- 12. Transition -- Part III: Trial -- 13. Testimony -- 14. A Cropped Portrait -- 15. Unsung -- 16. 360° -- Part IV: Imprisonment and Freedom -- 17. The Anarchy of Destiny -- 18. The Gita and the SHU -- Epilogue -- Notes -- Acknowledgments -- Appendix: Timeline of Rajat Gupta's Life -- Index.

OBJECTIVES: There has been a rapid increase in respiratory infections due to COVID-19, caused by SARS-CoV-2, a novel coronavirus, which is believed to have originated from Wuhan in China. The disease has taken a form of pandemic and is now present in all countries across the globe with nearly 5.4 million infections and 344,000 fatalities till date. In late March, the Indian government initiated a lockdown, which confined nearly 1.3 billion people, around one-sixth of humanity to home, in an effort to decrease the community transmission of COVID-19 disease and flatten the curve so that Indian health care is able to deal with a manageable number of cases. This lockdown, which started on March 25, 2020, has now been extended to May 17, 2020, a duration of 54 days, with further planned extension to May 31. During this lockdown, the authors noted an increase in the number of mixer grinder injuries and a change in the demography of suicidal attempts due to frustration resulting in injuries to upper limb. The authors have studied this phenomenon and compared the data with cases from previous year. MATERIAL AND METHODS: The case records of all patients coming to the emergency department and department of plastic surgery in the period of March 25, 2020, to May 17, 2020 (54 days), with injuries of upper limb were analyzed and data compared with data from 2019. The demography and mode of injuries were studied. RESULTS: There was an unusual increase in hand injuries due to mixer grinder in kitchen, 32 cases in 54 days (17.78/month) compared to 28 cases in 12 months in 2019 (2.34/month) with P < 0.001. There was also an increase in number of intended self-inflicted injuries in upper limb, as a result of psychological effects of rage and frustration with spouse due to long periods of confinement at home (3.89/month during lockdown period compared to 0.58 during 2019, P < 0.005) with change in demography compared to previous year. There was a decrease in upper limb injuries due to road traffic accidents, industrial ...

This research study investigates the effects of the large-scale installation of domestic heat pumps on the UK electricity supply over the short to medium term. A BREDEM-based dwelling energy model, incorporating a model of heat pump performance, is enhanced for the effects of varying monthly temperatures. Data from the English Housing Survey (2007) is analysed using this model to estimate electricity consumption to 2020 and 2050, and simulate scenarios for replacing existing heating systems by ground or air source heat pumps. The type of heat pump (ground or air source) is determined by dwelling plot dimensions data from the EHS. Modelling results for 2020 showed that a policy of replacing the heating systems with the highest emissions could reduce or at least minimise the increase in electricity consumption and carbon emissions. Results for 2050 showed that replacement of some 80% of current gas-fired systems would enable the UK to meet its target of 80% carbon emissions reduction in this sector when accompanied by simultaneous decarbonisation of the electricity supply. These results provide some support for the UK government's policy of subsidizing heat pump installations through the Renewable Heat Incentive payments whilst indicating that meeting emission targets requires far greater adoption of these systems than current ambitions.

The UK government has committed to achieving net zero carbon emissions by 2050. This will require a transformation of the housing sector as it has lagged previous emissions targets. Although millions of existing homes across the UK need energy improvements, the process of identifying suitable and eligible homes is presently a time-consuming task and energy suppliers are struggling to meet their targets. To address this challenge, this paper describes the application of a data-driven geographical information system-based approach to spatially identify suitable dwellings quickly and accurately by mapping and modelling baseline energy use and potential for energy retrofit measures, singularly and in combination. Drawing on publicly available datasets on housing and energy, combined with local datasets, a neighbourhood with high fuel poverty in Bicester (Oxfordshire, UK) was selected. The DECoRuM model was then used to estimate current energy use and potential for energy reduction on a house-by-house level. The improvement measures were aggregated to encourage bulk installations and drive down installation costs. House-level energy assessment in the selected area using DECoRuM shows that a package-based approach comprising building fabric and heating system upgrade and solar PVs is effective at significantly reducing energy consumption and energy bills, as well as fuel poverty. This spatially based urban energy modelling approach brings together energy calculations and spatial mapping to address the barriers to mass retrofit programmes. The data collected can also be used to build brokering services amongst those who need energy improvements (households) with those can provide retrofit measures (installers) and those can sponsor energy measures (energy suppliers).

Vertical Axis Wind Turbine (VAWT) is a viable proposition for small-scale uses like, rural electrification, pumping, desalinating, household applications etc in many developing countries including India. In this paper, a hybrid neuro-fuzzy controller has been developed using gradient-based training algorithm to evaluate the performance of a combined three-bladed Savonius-Darrieus rotor. The objective of the study is to design a controller that causes more uniform loading on the generator by minimizing fluctuations in output parameters with change of input and also that improves rotor performance. A two-input-single-output controller has been designed. The tip speed ratio and overlap have been taken as input parameters, and output parameters are power coefficients and torque coefficients. At the first step, the input data are fuzzified by assigning fuzzy levels to the input data sets, and then trained outputs are obtained by back propagation learning algorithm. The controller results are in good agreement with the experimental results both qualitatively and quantitatively. For power coefficient (Cp), the agreement is within 4.5%, and for torque coefficient (Ct) it is within 2%. Moreover, the performance of the hybrid neuro-fuzzy controller has also been compared with Fuzzy Logic Controller (FLC) & ANN controller. The present controller predicts smoother values of performance parameters compared with other controllers.

This paper presents new evidence from a nationwide cross-project meta-study investigating the magnitude and extent of the difference between designed and measured thermal performance of the building fabric of 188 low energy dwellings in the UK. The dataset was drawn from the UK Government's national Building Performance Evaluation programme, and comprises 50 Passivhaus (PH) and 138 non-Passivhaus (NPH) dwellings, covering different built forms and construction systems. The difference between designed and measured values of air permeability (AP), external wall/roof thermal transmittance (U-value) and whole house heat loss were statistically analysed, along with a review of thermal imaging data to explain any discrepancies. The results showed that fabric thermal performance gap was widespread especially in terms of AP, although the magnitude of underperformance was much less in PH dwellings. While measured AP had good correlation with measured space heating energy for PH dwellings, there was no relationship between the two for NPH dwellings. The regression analysis indicated that for every 1m3/h/m2 reduction in designed air permeability, the gap increased by 0.8 m3/h/m2@50Pa. Monte Carlo analysis showed that likelihood of AP gap was 78% in NPH dwellings designed to 5m3/h/m2@50Pa or lower. The study provides useful evidence for improving the fabric thermal performance of new housing through in-situ testing.

This paper presents new evidence from a nationwide cross-project meta-study investigating the magnitude and extent of the difference between designed and measured thermal performance of the building fabric of 188 low energy dwellings in the UK. The dataset was drawn from the UK Government's national Building Performance Evaluation programme, and comprises 50 Passivhaus (PH) and 138 non-Passivhaus (NPH) dwellings, covering different built forms and construction systems. The difference between designed and measured values of air permeability (AP), external wall/roof thermal transmittance (U-value) and whole house heat loss were statistically analysed, along with a review of thermal imaging data to explain any discrepancies. The results showed that fabric thermal performance gap was widespread especially in terms of AP, although the magnitude of underperformance was much less in PH dwellings. While measured AP had good correlation with measured space heating energy for PH dwellings, there was no relationship between the two for NPH dwellings. The regression analysis indicated that for every 1 m3/h/m2 reduction in designed air permeability, the gap increased by 0.8 m3/h/m2@50 Pa. Monte Carlo analysis showed that likelihood of AP gap was 78% in NPH dwellings designed to 5 m3/h/m2@50 Pa or lower. The study provides useful evidence for improving the fabric thermal performance of new housing through in-situ testing.

Recent Government funding in the UK has enabled 22 low carbon community organisations to work with the private and academic sector to understand and reduce energy consumption in domestic and non-domestic buildings. This has helped communities prepare for policy mechanisms such as the national Green Deal programme which aims to improve existing housing and non-domestic buildings by offering up-front loans to be repaid by energy savings. This paper presents the role and application of a unique carbon mapping approach, which has enabled five of these low carbon communities to rapidly assess on a house-by-house level, the potential for improving the energy efficiency of their housing stock. DECoRuM, an award-winning GIS-based carbon counting model is used to measure, model, map and manage energy use and CO2 emission reductions from approximately 1,300 houses across five communities, displaying estimates of energy use and carbon emissions before and after community action. Incremental packages of energy saving measures and low carbon technologies are assessed for their impact on CO2 emissions to reveal further potential for large-scale refurbishment in the local area. Eligibility for the Green Deal is tested to show that on average 72 per cent of homes over all communities are suitable for finance. Through community events, results are visualised and fed back to the householders using colour-coded spatial maps along with thermal imaging. Findings from this study are relevant for policy-making and practitioners engaged in area-based carbon reductions.

Steady-state two-dimensional Computational Fluid Dynamics (CFD) simulations were performed using Fluent 6.0 software to analyze the flow physics of 3-bladed straight chord H-Darrieus wind turbine having blade twist of 300 for 10% of its chord at the trailing ends. The flow was simulated using finite volume method coupled with moving mesh technique to solve mass and momentum conservation equations. The standard k-ε turbulence model with enhanced wall condition was used. Second-order upwind discretization scheme was adopted for pressure-velocity coupling of the flow. Flow physics of the turbine was analyzed with the help of pressure and velocity contours. It was found that velocity magnitude decreases from upstream to downstream side across the turbine, which will cause overall lift for the turbine. Further, blade twist at the trailing ends creates circulations that interact with the blades in a direction opposite to the direction of rotation of the turbine which would enhance power production for the three bladed turbine.

The UK Government announced in 2020 its 'Ten Point Plan' for a green industrial revolution, which includes a challenging target to install 600,000 heat pumps per year by 2028. Balancing electricity supply and demand locally is key to the success of achieving this target. This paper uses a natural experiment approach to gather early insights into the change in energy use, indoor temperature and relative humidity profiles before and after installation of smart ground source heat pumps (GSHPs) and smart controls in nine social housing dwellings (5 bungalows, 4 flats) located in a socially-deprived area of Oxford (UK). The GSHPs replaced night-storage heaters and integrate smart controls to optimise heat production in line with outside weather and resident preferences. Indoor and outdoor temperature and relative humidity were continuously monitored at 15' intervals using blue-tooth enabled data loggers across the nine dwellings. In a subset of two dwellings, electricity use was monitored remotely using CT loggers from October to December 2020. Household surveys were conducted to establish the household characteristics, socio-demographics and the way residents heat their home. No correlation was observed between actual annual energy costs (self-reported) and EPC ratings. Indoor temperatures were found to be more stable across the nine dwellings after installation of heat pumps. Despite having similar size, number of occupants and occupancy patterns, there was wide variation in the range of indoor temperatures measured across the sample. Post-heat pump installation bungalows experienced higher increase in indoor temperature as compared to flats, with mean indoor temperatures of over 25°C observed in mid-terraced bungalows, due to improved air-tightness as a result of cavity wall insulation, constant heating and limited window opening. Smart controls were found to be regularly used by residents to easily increase the heating set point temperature to overcome the low output temperatures of the heat pumps. Following heat ...

This paper presents new evidence from a nationwide meta-study investigating the magnitude and extent of the difference between predicted and measured energy performance (energy performance gap) of over 50 low energy dwellings in the UK. Statistical testing of predicted and measured energy use is undertaken to assess the impact of occupancy related factors (number of occupants, occupancy type, pattern) on energy performance, and to predict the likelihood of the space heating energy performance gap in UK new build housing. The dataset was drawn from the UK Government's National Building Performance Evaluation programme – which included the final reports, Standard Assessment Procedure (SAP) calculations and Domestic Energy Assessment and Reporting Methodology (DomEARM) results – and comprises 30 Passivhaus (PH) and 62 non-Passivhaus (NPH) dwellings, covering different built forms and construction systems. The majority of the sample comprised social housing dwellings built with masonry and timber frames and equipped with mechanical ventilation heat recovery systems. Although the average annual energy use (gas and electricity) in the PH and NPH dwellings was found to be 73kWh/m2 and 117 kWh/m2 respectively, electricity use was not significantly different between the two groups. All dwellings in the sample performed better than UK Building Regulations, however average energy use was higher than predicted by an average of 60%, but as much as 147% in PH and 241% in NPH dwellings. The overwhelming majority - 13 out of 14 PH and 35 out of 43 NPH dwellings - did not meet the predicted energy use, demonstrating a performance gap of 22 kWh/m2/year and 45 kWh/m2/year respectively. Occupancy was found to influence 45% of total energy use, with occupancy pattern being more critical than occupancy type and number of occupants. Despite the high levels of fabric thermal standards, space heating was found to be the largest energy end use (28% in PH and 42% in NPH dwellings) followed by domestic hot water (28%) and small appliances (21%), while the ratio of regulated to unregulated energy was found to be 70:30. The probability of an energy performance gap in space heating occurring in the population of new build housing was found to be over 80%. The study findings are important for bridging the gap between intent and actual performance of new low energy housing.

Helical Savonius rotor exhibits better performance characteristics at all the rotor angles compared to conventional Savonius rotor. However studies related to the performance measurement and flow physics of such rotor are very scarce. Keeping this in view, in this paper, a three dimensional Computational Fluid Dynamics analysis using commercial Fluent 6.2 software was done to predict the performance of a two-bucket helical Savonius rotor without shaft and with end plates in a complete cycle of rotation. A two-bucket helical Savonius rotor having height of 60 cm and diameter of 17 cm with 45° bucket twist angle was designed using Gambit. The buckets were connected at the top and bottom circular end plates, which are 1.1 times the rotor diameter. The k-ε turbulence model with second order upwind discretization scheme was adopted with standard wall condition. Power coefficients (Cp) and torque coefficients (Ct) at different tip speed ratios were evaluated at different rotor angles. From the investigation, it was observed that power coefficient increased with increase of tip speed ratio up to an optimum limit, but then decreased even further tip speed ratio was increased. Further investigation was done on the variations of Cp & Ct in a complete cycle of rotation from 0° to 360° in a step of 45° rotor corresponding to the optimum tip speed ratio. The value of Cp at all the rotor angles is positive. Moreover, velocity magnitude contours were analyzed for each rotor angle and it could be concluded that high aerodynamic torque and power can be expected when the rotor is positioned at 45º & 90º with respect to incoming flow.