A multi-input energy harvesting system with independent energy harvesting block and power management block

In the conventional approach widely used for multi-input energy harvesting (MIEH), energy harvesting, energy combining, and power conversion are performed integrally in an inductor sharing block through time multiplexing operations, which is not suitable for hot-pluggable systems. In the MIEH system proposed in this paper, an energy harvesting block (EHB) and a power management block (PMB) are independent of each other to increase the modularity of the system. Therefore, the EHB can be optimized to extract maximum power from energy sources, and the PMB can be focused on combining input energies and converting power effectively. This paper mainly focuses on the design and implementation of the EHB. For light, vibration, and thermal energy, the measured peak power efficiencies of the EHB implemented using a 0.35 μm CMOS process are 95.2%, 92.5%, and 95.5%, respectively. To confirm the functionality and effectiveness of the proposed MIEH system, a PMB composed of simple charge pump circuits and a power management unit has also been implemented and verified with the designed EHB.

Empirical Correlations of Spectral Input Energy with Peak Amplitude, Cumulative, and Duration Intensity Measures

ABSTRACT In earthquake engineering, it is acknowledged that a vector of intensity measures (IMs) can better predict seismic structural responses than a single measure. Hence, a vector of IMs is widely applied in a number of applications, such as probabilistic seismic hazard analysis, probabilistic seismic risk analysis, and ground-motion selections. Spectral input energy (EI) has been demonstrated as a promising IM in earthquake engineering, especially in the energy-based seismic design of structures. However, this important measure has not been included in the vector of IMs. Therefore, it is worthwhile to incorporate EI with other important IMs by examining correlations. This study analyzes the empirical correlations of spectral EI with peak amplitude-based IMs, cumulative-based IMs, and duration-related IMs. It is found that spectral absolute EI has strong correlations with peak ground velocity at all investigated periods. However, spectral EI is negatively correlated with duration-based IMs. To demonstrate the applicability of the examined correlations, a simple example is finally presented by employing EI for the ground-motion selections and seismic hazard assessment based on the generalized conditional intensity measure approach.

Analysis of critical issues in retrofitting of ICE vehicles

Vehicle population is increasing at an alarming rate causing cities, and towns to suffer air pollution due to inefficient engines. Every year millions of vehicles are being manufactured and scrapped. Disposal or scrapping of vehicles before their useful life is not a good option. All the parts and systems of a vehicle wear out at different rates. By employing this technology of retrofit for the next 10 to 15 years, the owners will be able to contribute to society by decreasing input energy for massive automobile industries. Based on the life span of automobile parts a range of age has been found in this research at which retrofit can be carried out. In this research, cost analysis of vehicles has been carried out which shows a decrease in performance with increased maintenance, repair, and replacement cost. A mathematical model has been created for performance and cost. The minima of this mathematical model are known as retrofit age. It has been shown in this research that the time has come to adopt this technology, due to inadequate recycling of automobile parts, limited processing plants, and limited scraps yard. For this study, Honda Activa 5G, Bajaj pulsar 500, and Maruti Baleno has been considered.

Study on Energy Evolution and Damage Constitutive Model of Siltstone

In order to study the energy evolution characteristics and damage constitutive relationship of siltstone, the conventional triaxial compression tests of siltstone under different confining pressures are performed, and the evolution laws of input energy, elastic strain energy and dissipative energy of siltstone with axial strain and confining pressure are analyzed. According to the test results, the judgment criterion of the rock damage threshold is improved, and an improved three-shear energy yield criterion is proposed., The damage constitutive equation of siltstone is established based on the damage mechanics theory through the principle of minimum energy consumption and by considering the residual strength of rock, and lastly, the rationality of the model is verified by experimental data. The results reveal that (1) both the input energy and dissipative energy gradually increase with the increase of axial strain, and the elastic strain energy first increases and then decreases with the increase of axial strain, and reaches its maximum at the peak. (2) The input energy and dissipation energy increase exponentially with the increase of the confining pressure, and the elastic strain energy increases linearly with the increase of confining pressure. (3) According to the linear relationship between the sum of shear strain energy and hydrostatic pressure, an improved three-shear energy yield criterion is established. (4) The model curve can better describe the strain softening stage and the residual strength characteristics of siltstone. The relative standard deviation between the model results and the test results is only 4.35%, which verifies the rationality and feasibility of the statistical damage constitutive model that is established in this paper.

Energy Budgeting of Paddy-Pulse Cropping System in Bhadrak District of Odisha and Assessment of Emission from Paddy Straw Burning

Energy auditing of an existing production system helps to assess its energy-use and energy efficiency. The average input energy of paddy-black gram (PB) cropping system (19,862.01 MJ.ha-1) was higher than paddy-green gram (PG) (18,972.34 MJ.ha-1) cropping system in Bhadrak, Odisha. Harvesting and transport operation required highest operational energy for PG (35.57%) and PB (41.20%) farms; while, threshing and winnowing consumed the second highest input energy with 21.34% and 22.71% for PG and PB farms, followed by land preparation with 21.87% and 20.10% respectively. Linear regression data of PG and PB systems showed significant effect (p<0.05) of predictors with R2 values of 87.70% and 82.20% for total output energy and grain energy, respectively; confirming a good fit among the data. The output energy of PB cropping system was 13.91% higher than that of PG cropping system. The PB cropping system, with energy utilisation efficiency (EUE) of 10.31 and 11.82, was more energy-efficient than PG system with EUE of 9.32 and 11.01 for “NC” and “C” farms, respectively. The net energy return of PBC farm was highest with 2,04,505.31 MJ.ha-1. Amongst various pollutants emitted from paddy straw burning in Odisha; CO2 (5,51,296.0 Mg.yr-1), CO (13,102.72 Mg.yr-1), and TPM (4,908.80 Mg.yr-1) had highest share. The quantity of major GHGs (N2 O, CH4 ) released into the atmosphere through paddy straw burning was estimated as 26.43 Mg.yr-1 and 453.12 Mg.yr-1, respectively. Use of straw baler can prevent straw burning, and reduce emission from paddy fields by 2805.54 kg.ha-1 of CO2 and 66.69 kg.ha-1 of CO, 5.96 kg.ha-1 of NOx , 24.98 kg.ha-1 of TPM. Alternatively, use of mulcher can also reduce emission from paddy fields by 2924.44 kg.ha-1 of CO2 and 69.51 kg.ha-1 of CO, 6.21 kg.ha-1 of NOx , 26.04 kg.ha-1 of TPM. The cost of operation of a baler and mulcher were 8,617.0 ₹ ha-1 and 2,543.0 ₹ ha-1, respectively. Input energy and energy saved in paddy fields by baler were 820.0 MJ.ha-1 and 16,928.0 MJ.ha-1; and 266.0 MJ.ha-1 and 24,458.0 MJ.ha-1 by mulcher, respectively