@article{ercumen_mertens_arnold_benjamin-chung_hubbard_ahmed_kabir_khalil_kumar_rahman_et al._2018, title={Effects of Single and Combined Water, Sanitation and Handwashing Interventions on Fecal Contamination in the Domestic Environment: A Cluster-Randomized Controlled Trial in Rural Bangladesh}, volume={52}, ISSN={["1520-5851"]}, DOI={10.1021/acs.est.8b05153}, abstractNote={Water, sanitation, and hygiene interventions have varying effectiveness in reducing fecal contamination in the domestic environment; delivering them in combination could yield synergies. We conducted environmental assessments within a randomized controlled trial in Bangladesh that implemented single and combined water treatment, sanitation, handwashing (WSH) and nutrition interventions (WASH Benefits, NCT01590095). After one and two years of intervention, we quantified fecal indicator bacteria in samples of drinking water (from source or storage), child hands, children’s food and sentinel objects. In households receiving single water treatment interventions, Escherichia coli prevalence in stored drinking water was reduced by 50% and concentration by 1-log. E. coli prevalence in food was reduced by 30% and concentration by 0.5-log in households receiving single water treatment and handwashing interventions. Combined WSH did not reduce fecal contamination more effectively than its components. Interventions did not reduce E. coli in groundwater, on child hands and on objects. These findings suggest that WSH improvements reduced contamination along the direct transmission pathways of stored water and food but not along indirect upstream pathways. Our findings support implementing water treatment and handwashing to reduce fecal exposure through water and food but provide no evidence that combining interventions further reduces exposure.}, number={21}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Ercumen, Ayse and Mertens, Andrew and Arnold, Benjamin F. and Benjamin-Chung, Jade and Hubbard, Alan E. and Ahmed, Mir Alvee and Kabir, Mir Himayet and Khalil, Md. Masudur Rahman and Kumar, Ashish and Rahman, Md. Sajjadur and et al.}, year={2018}, month={Nov}, pages={12078–12088} }
 @inproceedings{kumar_parashar_baliga_bhattacharya_2018, title={Single shot avalanche energy characterization of 10kV, 10A 4H-SiC MOSFETs}, volume={2018-March}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85046957199&partnerID=MN8TOARS}, DOI={10.1109/apec.2018.8341404}, abstractNote={Higher switching frequency capability and lower switching loss associated with 10kV 4H-SiC MOSFETs make them attractive for medium voltage applications, mostly in inductive circuits e.g. solid state transformers, grid connectors and high speed machine drives. Due to exposure to inductive circuits, avalanche ruggedness of these MOSFETs needs to be established to improve their reliability in case of unintended unclamped inductive switching. In this paper, the avalanche ruggedness of 10kV, 10A 4H-SiC MOSFETs is established experimentally using single shot unclamped inductive switching. The minimum and the maximum energy is found out for the MOSFET to remain in avalanche without being failed permanently. The junction temperature at the permanent failure is estimated using semiconductor device physics.}, booktitle={Conference Proceedings - IEEE Applied Power Electronics Conference and Exposition - APEC}, author={Kumar, A. and Parashar, S. and Baliga, J. and Bhattacharya, Subhashish}, year={2018}, pages={2737–2742} }
 @inproceedings{kumar_ravichandran_singh_shah_bhattacharya_2017, title={An intelligent medium voltage gate driver with enhanced short circuit protection scheme for 10kV 4H-SiC MOSFETs}, volume={2017-January}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85041440358&partnerID=MN8TOARS}, DOI={10.1109/ecce.2017.8096486}, abstractNote={Designing of gate drivers for high voltage SiC power devices in medium voltage applications is challenging due to high dv/dt and di/dt at the switching instants. During short circuit fault, the device current rises with high di/dt, and eventually the device fails within few of micro seconds if not protected. Short circuit protection of power devices is an essential feature to improve reliability of converters. In this paper, a novel gate driver is developed with short circuit protection scheme, suitable for 10kV, 10A 4-H SiC MOSFETs. It utilizes the de-sat sensing scheme to detect the fault, and clears the fault by turning off the gate pulse in two stages. The trip time at the short circuit fault is much smaller than the short circuit withstanding time of 10kV 4H-SiC MOSFETs. The gate driver is qualified with appropriate experimental test bench for validation of short circuit protection feature, over-current limit and continuous operation for the 10kV MOSFETs.}, booktitle={2017 IEEE Energy Conversion Congress and Exposition, ECCE 2017}, author={Kumar, A. and Ravichandran, A. and Singh, S. and Shah, S. and Bhattacharya, Subhashish}, year={2017}, pages={2560–2566} }
 @inproceedings{kumar_vechalapu_bhattacharya_veliadis_brunt_grider_sabri_hull_2017, title={Effect of capacitive current on reverse recovery of body diode of 10kV SiC MOSFETs and external 10kV SiC JBS diodes}, volume={2017-December}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85046697191&partnerID=MN8TOARS}, DOI={10.1109/wipda.2017.8170548}, abstractNote={The body diodes of 10kV SiC MOSFETs can be used as anti-parallel diodes in medium voltage converters instead of widely used SiC JBS and PiN diodes. Characterization of switching loss of the body diodes is required to evaluate its candidature for replacement of JBS/PiN diodes. Normally, double pulse test setup is used to observe the reverse recovery behavior of the diodes. But, in high voltage diodes, due to large dv/dt the capacitive current becomes significant, and it superimposes on the reverse recovery current waveform of the diode, misleading the reverse recovery loss data, if the capacitive current is ignored. In this paper, contribution of the capacitive current in the reverse recovery is segregated, which helps in determining actual reverse recovery loss of the diode in double pulse test circuit. Two-slope turn-on characteristic of 15kV SiC IGBT is employed to support the existence of this capacitive current. Using the proposed segregation technique, reverse recovery of the body diode of 10kV SiC MOSFETs is compared with that of 10kV SiC JBS diode.}, booktitle={2017 IEEE 5th Workshop on Wide Bandgap Power Devices and Applications, WiPDA 2017}, author={Kumar, A. and Vechalapu, K. and Bhattacharya, Subhashish and Veliadis, V. and Brunt, E. Van and Grider, D. and Sabri, S. and Hull, B.}, year={2017}, pages={208–212} }