A PWM Method for Reducing dv/dt and Switching Losses in Two-Stage Power Converters

Today\u27s semiconductor devices are accompanied by high switching frequencies (\u3e kilo-hertz) and small transition times (\u3c micro-seconds). Such fast transition times are accompanied by undesirable effects such as voltage overshoots at the load terminals, ground leakage currents, wide-band electromagnetic noise, etc. With the advent of wide band-gap devices, several applications are moving towards higher switching frequency operation with at-least an order of magnitude reduction in transition times. While these characteristics are considered necessary to break the next-generation barriers in power density, efficiency and applicability, the undesirable effects due to faster transitions are expected to present obstacles. This work proposes a PWM approach to modify the shape of the switching voltages to overcome the disadvantages of the fast transition times without any increase in switching losses. In fact, several of the switching transitions feature ZVS operation, resulting in reduced switching losses. The paper discusses the analytical details of the approach using a simple DC-DC boost-buck converter and extends it to a DC to three-phase AC converter using the principles of space vector modulation. The paper presents detailed simulation and comparative results in terms of voltage over-shoots over long cables, loss calculations and electromagnetic noise. Results from a laboratory-scale working prototype confirm the benefits of the proposed approach in terms of EMI and loss reduction

Critical analysis of Manasika Bhava in Anurjatajanya (allergic) diseases - A Survey Study

People are just as happy as they make up their minds to be. The state of mind defines ones healthy or unhealthy status. Human body and mind are always interlinked for the existence of life. Any alteration in functioning of body or mind gives formal invitation for various disorders. Ayurveda treatise has inculcated the importance of Manasika Bhava like Krodha (anger), Shoka (grief), Bhaya (fear) etc. at every influential place. In the present survey study, the inevitability of Manasika Bhava in Anurjatajanya (allergic) diseases is verified with the generated evidences. The World Health Organization (WHO) estimates 300 million individuals have asthma worldwide, a figure that could increase to 400 million by 2025 if trends continue. This is paralleled with a rising prevalence of skin allergies along with life threatening allergies like food allergies, drug allergies and anaphylaxis and more complex forms. This survey study end up with the result that, over 96% of the total registered allergic patients were with one or more abnormal Manasika Bhava

A comparative study of effect of fluoroquinolones on blood glucose levels in rats

Background: Fluoroquinolones (FQ) are frequently prescribed because of their broad-spectrum applicability in treatment of community acquired pneumonia and urinary tract infections. Increased use has raised some concerns regarding side effects like dysglycaemia, tendon rupture and QT interval prolongation. Gatifloxacin was banned in India in 2011 for causing fatal hypoglycemia. This study compares the effect of different fluoroquinolones on blood glucose levels in rats.Methods: 24 rats were divided into four study groups. Each group was administered one fluoroquinolone namely levofloxacin 9 mg, moxifloxacin 7.2 mg, ciprofloxacin 18 mg and ofloxacin 14.4 mg respectively for five days. The changes in blood glucose levels were observed for 10 days.Results: The mean blood glucose levels in all the four groups dropped below the baseline by day five. A statistically significant reduction in mean glucose levels was found in the moxifloxacin, ciprofloxacin and levofloxacin group. Among the rats that were given ofloxacin, the reduction in the mean blood glucose levels was not statistically significant. After stopping the drugs, the blood glucose levels in all the four groups returned near to the baseline within five days.Conclusions: The use of fluoroquinolones causes hypoglycemia in rats. The blood glucose level reduction associated with moxifloxacin was maximum, whereas ofloxacin appeared to have the minimum effect on blood glucose levels. These effects do not appear to be permanent and the dysglycaemia subsided after the drugs were stopped

Functional dissection of the catalytic carboxyl-terminal domain of Origin Recognition Complex Subunit 1 (PfORC1) of the human malaria parasite Plasmodium falciparum

Origin Recognition Complex subunit 1 (ORC1) is essential for DNA replication in eukaryotes. The deadly human malaria parasite Plasmodium falciparum contains an ORC1/CDC6 homolog with several interesting domains at the catalytic carboxyl-terminal region that include a putative nucleoside triphosphate-binding and hydrolysis domain, a putative PCNA-Interacting-Protein (PIP) motif and an extreme C-terminal region that shows poor homology with other ORC1 homologs. Due to the unavailability of a dependable inducible gene expression system, it is difficult to study the structure and function of essential genes in Plasmodium. Using a genetic yeast complementation system and biochemical experiments, here we show that the putative PIP domain in ORC1 that facilitates in vitro physical interaction with PCNA is functional in both yeast (Saccharomyces cerevisiae) and Plasmodium in vivo, confirming its essential biological role in eukaryotes. Furthermore, despite having less sequence homology, the extreme C-terminal region can be swapped between S. cerevisiae and P. falciparum and it binds to DNA directly, suggesting a conserved role of this region in DNA replication. These results not only provide us a useful system to study the function of the essential genes in Plasmodium, they help us to identify the previously undiscovered unique features of replication proteins in general

Multi-task Neural Network for Non-discrete Attribute Prediction in Knowledge Graphs

Many popular knowledge graphs such as Freebase, YAGO or DBPedia maintain a list of non-discrete attributes for each entity. Intuitively, these attributes such as height, price or population count are able to richly characterize entities in knowledge graphs. This additional source of information may help to alleviate the inherent sparsity and incompleteness problem that are prevalent in knowledge graphs. Unfortunately, many state-of-the-art relational learning models ignore this information due to the challenging nature of dealing with non-discrete data types in the inherently binary-natured knowledge graphs. In this paper, we propose a novel multi-task neural network approach for both encoding and prediction of non-discrete attribute information in a relational setting. Specifically, we train a neural network for triplet prediction along with a separate network for attribute value regression. Via multi-task learning, we are able to learn representations of entities, relations and attributes that encode information about both tasks. Moreover, such attributes are not only central to many predictive tasks as an information source but also as a prediction target. Therefore, models that are able to encode, incorporate and predict such information in a relational learning context are highly attractive as well. We show that our approach outperforms many state-of-the-art methods for the tasks of relational triplet classification and attribute value prediction.Comment: Accepted at CIKM 201

Microbial Study of Drinking Water in the Government Hospitals of Patna District, Bihar, India

This study was carried out to evaluate the status of drinking water supplied in six different government hospitals of the Patna capital of Bihar, India. A total of 14 drinking water samples was collected aseptically in sterile container during the month of August 2017. Most probable number (MPN) test was done to detect the Coliforms in drinking water samples. A total of 11out of 14 samples shows very high MPN value, which are above the WHO standard of concentration of Coliforms which must be zero in safe drinking water . Analysis was performed by using culture and biochemical methods. This study has therefore shown the need for continuous monitoring of drinking water supply system. This study indicates that regular water monitoring the supply and availability of pathogens free drinking water

Object search by manipulation

We investigate the problem of a robot searching for an object. This requires reasoning about both perception and manipulation: some objects are moved because the target may be hidden behind them, while others are moved because they block the manipulator’s access to other objects. We contribute a formulation of the object search by manipulation problem using visibility and accessibility relations between objects. We also propose a greedy algorithm and show that it is optimal under certain conditions. We propose a second algorithm which takes advantage of the structure of the visibility and accessibility relations between objects to quickly generate plans. Our empirical evaluation strongly suggests that our algorithm is optimal under all conditions. We support this claim with a partial proof. Finally, we demonstrate an implementation of both algorithms on a real robot using a real object detection system