A New Smart Grid Hybrid DC–DC Converter with Improved Voltage Gain and Synchronized Multiple Outputs

This paper introduces a new hybrid DC-DC converter with enhanced voltage gain and synchronized multiple output capabilities, specifically tailored for smart grid applications. The proposed converter is based on the integration of non-isolated Zeta and Mahafzah converters, comprising a single controlled switch, two diodes, three inductors, and two coupling capacitors. The primary objective of this novel hybrid converter is to improve voltage gain as compared to conventional Zeta and Mahafzah topologies. By achieving higher voltage gain at lower duty cycles, the converter effectively reduces voltage stress on semiconductor switches and output diodes, thereby enhancing overall performance and reliability. A comprehensive examination of the hybrid converter's operating principle is presented, along with detailed calculations of duty cycle and switching losses. The paper also explores the converter's application in smart grids, specifically in the context of renewable energy systems and electric vehicles. Two distinct scenarios are analyzed to evaluate the converter's efficacy. Firstly, the converter is assessed as a DC-DC converter for renewable energy systems, highlighting its relevance in sustainable energy applications. Secondly, the converter is evaluated as an electric vehicle adapter, showcasing its potential in the transportation sector. To validate the converter's performance, extensive simulations are carried out using MATLAB/SIMULINK with parameters set at 25 kW, 200 V, and 130 A. The simulation results demonstrate the converter's ability to efficiently supply multiple loads with opposing energy flows, making it a promising technology for optimized grid management and energy distribution. Moreover, the paper investigates the total harmonic distortion (THD) of the grid current, focusing on its impact in smart grid environments. Notably, the new hybrid converter topology achieves a THD of 21.11% for the grid current, indicating its ability to effectively mitigate harmonics and improve power quality. Overall, this research introduces a cutting-edge hybrid DC-DC converter that enhances voltage gain and synchronizes multiple outputs, specifically catering to the requirements of smart grid applications. The findings underscore the converter's potential to significantly contribute to the advancement of efficient and resilient power conversion technologies for smart grids, enabling seamless integration of renewable energy systems and electric vehicles into the grid

Low incidence of hypervirulent clinical klebsiella pneumoniae producing carbapenemases among Jordanian hospitalized patients

Background:  Klebsiella species are widely present in the environment and colonize mucosal surfaces of humans. The organism is responsible for various community and hospital-acquired infections. Increased incidence of isolates producing K .pneumoniae carbapenemases (KPCs)  in infected patients has become a significant problem in many countries, especially those new hypervirulent clinical variant (hvKP).  This prospective study was intended to detect the incidence, virulence factors and carbapenems resistant gene (blakpc2) in K. pneumoniae isolates among Jordanian patients.Methods:  A total of 104 klebsiella species isolates were collected randomly from three major hospitals in Amman, Jordan, over the period from September 2012 to October 2013. These isolates were investigated for incidence of  K.pneumoniae , antimicrobial susceptibility and detection of virulence factors and kpc gene using PCR .Results: A total of 75 (72%) of the collected isolates were confirmed as K. pneumoniae using PCR, and 74% of these were MDR to at least 3 antibiotic classes. The percentage of the virulence factors K1, K2, K5, rmpA and aerobactin were 0%, 4%, 0%, 5.3% and 10.7%, respectively. Resistant to cabapenems was detected in 18/75 (24% ) of K . pneumoniae isolates, and 10 (13.3%) of these have the kpc genes .Conclusion: This study confirms the high incidence rate of MDR K. pneumoniae and low incidence of (KPCs) isolates in Jordanian patients.  There were few isolates associated with virulence factor genes causing hvKP, and no significant correlation demonstrated between the presence of virulence factors and kpc gene in these isolates

Masked Interval Routing: a New Routing Scheme

We introduce the new Masked Interval Routing Scheme, MIRS for short, where a maskis added to each interval to indicate particular subsets of "consecutive" labels. Interval routing becomes more flexible, with the classical IRS scheme being a special case of MIRS. We then take two directions. First we show that the interval information stored in the network may be drastically reduced in the hard cases, proving that in globe graphs of O(n^2) vertices the number of intervals per edge goes down from Omega(n) to O(log n). The technique is then extended to globe graphs of arbitrary dimensions. Second we show that MIRS may be advantageously used in fault-tolerant networks, proving that optimal routing with one interval per edge is still possible in hypercubes with a "harmless" subset of faulty vertices. This work is aimed to introducing a new technique. Further research is needed in both the directions taken here. Still, the examples provided show that MIRS may be useful in practical applications