56 research outputs found

    Optimal Controller Design and Dynamic Performance Enhancement of High Step-up Non-Isolated DC-DC Converter for Electric Vehicle Charging Applications

    Get PDF
    Ideally, traditional boost converters can achieve a high conversion ratio with a high-duty cycle. But, in regular practice, due to low conversion efficiency, RR reverse-recovery, and EMI (electromagnetic interference) problems, the high voltage gain cannot be performed, whereas CIBC (coupled inductor-based converters) can achieve high voltage gain by re-adjusting the turn ratios. Even though the leakage inductor of the CI (coupled inductor) makes some problems like voltage spikes on the main connectivity switch, high power dissipation, and voltage pressure can be minimized by voltage clamp. In this paper, a non-isolated DC-DC converter with high voltage gain is demonstrated with 3 diodes, 3 capacitors, 1-inductor, and a coupled inductor. The main inductor is connected to the input to decrease the current ripple. The voltage stress at main switch S is shared by diode D1 and capacitor C1 and the main switch is turned ON under zero current, hence it turns to low switching losses. This paper proposes two controllers like proportional-integral (PI) controller and fuzzy logic (FLC) for dc-dc converter. Furthermore, it demonstrates the operation, design, mathematical analysis, and performance of DC-DC converter using controllers for efficient operation of the system is performed using simulations in MATLAB 2012b

    Tell Me Where to Go: A Composable Framework for Context-Aware Embodied Robot Navigation

    Full text link
    Humans have the remarkable ability to navigate through unfamiliar environments by solely relying on our prior knowledge and descriptions of the environment. For robots to perform the same type of navigation, they need to be able to associate natural language descriptions with their associated physical environment with a limited amount of prior knowledge. Recently, Large Language Models (LLMs) have been able to reason over billions of parameters and utilize them in multi-modal chat-based natural language responses. However, LLMs lack real-world awareness and their outputs are not always predictable. In this work, we develop NavCon, a low-bandwidth framework that solves this lack of real-world generalization by creating an intermediate layer between an LLM and a robot navigation framework in the form of Python code. Our intermediate shoehorns the vast prior knowledge inherent in an LLM model into a series of input and output API instructions that a mobile robot can understand. We evaluate our method across four different environments and command classes on a mobile robot and highlight our NavCon's ability to interpret contextual commands.Comment: 8 pages (24 with references and appendix), 6 Figure

    THE PHARMACOECONOMIC IMPACT OF GASTRO-PROTECTIVE AGENTS AT A TERTIARY CARE HOSPITAL

    Get PDF
    Objectives: The study aimed to evaluate the pharmacoeconomic impact of gastro-protective agents (GPA) by carrying out cost-benefit analysis (CBA) and cost-effective analysis (CEA). Methods: This prospective observational study was carried out by simple randomization technique at Karnataka Institute of Medical Science, Hubballi. Data used were socio-economic details based on modified B. G Prasad scale. Current Index of Medical Specialists updated version March 2021 was used for CBA and CEA. Regression analysis was the statistical tool used in the study. Results: A total of 120 participants were included in the study. 57.5% were male and 42.5% were female. 3.33% were pediatrics, 32.5% were young adults, 37.5% were elder adults and 26.67% were geriatrics. Out of 120 samples, 94 participants were prescribed with pantoprazole, other drugs prescribed include domperidone and pantoprazole, rabeprazole, and ranitidine. The CBA revealed ratio of benefits over costs for pantoprazole was 3.86, ranitidine was 9.31, pantoprazole and domperidone was 0.84 and rabeprazole was 0.84. Additional cost of 138.30 Indian Rupee must be spent on pantoprazole over ranitidine to get cost-effective treatment without disease for one whole year. Conclusion: The CBA revealed that maximum patients received benefits for pantoprazole. CEA gives an idea on best effective treatment over two drugs of different class. Our study concludes that pantoprazole is deemed to be superior over other drugs of GPA prescribed among study participants

    Mems integrated reconfigurable antenna for cognitive public safety radios

    Get PDF
    The frequency reconfigurable volumetric PIFA presented in this paper is designed to switch between two US public-safety bands, one operating at 700MHz and the other having a bandwidth of 17% around 850MHz - in effect covering a range from 800MHz to 900MHz. The reconfigurability is limited to only the ground and patch layers as an aim to minimize the number of MEMS switches used. The radiation pattern of the antenna maintains its shape and the maximum gain over this reconfigurable band of operation, 700 ā€“ 900 MHPostprint (published version

    Three dimensional microfabricated broadband patch and multifunction reconfigurable antennae for 60 GHz applications

    Get PDF
    In this paper we present two antenna designs capable of covering the IEEE 802.11ad (WiGig) frequency band (57-66 GHz and 59-66 GHz respectively). The work below reports the design, microfabrication and characterization of a broadband patch antenna along with the design and microfabrication of multifunction reconfigurable antenna (MRA) in its static form excluding active switching. The first design is a patch antenna where the energy is coupled with a conductor-backed (CB) coplanar waveguide (CPW)-fed loop slot, resulting in a broad bandwidth. The feed circuitry along with the loop is formed on a quartz substrate (at 60 GHz), on top of which an SU-8-based three-dimensional (3D) structure with air cavities is microfabricated. The patch metallization is deposited on top of this structure. The second design is a CB CPW-fed loop slot coupled patch antenna with a parasitic layer on top. The feed circuitry along with the loop is formed on a quartz substrate. On top, the patch metallization is patterned on another quartz substrate. The parasitic pixels are deposited on top of these two quartz layers on top of an SU-8 based 3D structure with air cavities. Ā© 2015 EurAAP

    Three-dimensional microfabricated broadband patch antenna for wigig applications

    Get PDF
    The design, microfabrication, and characterization of a broadband patch antenna capable of covering the entire IEEE 802.11ad (WiGig) frequency band (57-66 GHz) are presented in this letter. A conductor-backed (CB) coplanar waveguide (CPW)-fed loop slot couples the energy to the patch antenna, resulting in a broad bandwidth. The feed circuitry along with the loop is formed on a quartz substrate (\varepsilon-{\rm r} = 3.9, \tan \delta = 0.0002 at 60 GHz), on top of which an SU-8-based three-dimensional (3-D) structure with air cavities is microfabricated. The patch metallization is deposited on top of this 3-D structure. While the main role of the structure made out of SU-8 material is to provide a mechanical support for the patch metallization, the antenna takes advantage of the air cavities underneath, thus resulting in an antenna substrate with a very low loss. This, in turn, improves the overall antenna performances. The simulated and measured impedance characteristics agree well, showing {\sim}15\hbox{\%} bandwidth. Also, the radiation pattern results demonstrate the integrity of radiation pattern with reasonably constant gain values (average {\sim}6.4~dB) in the broadside direction over the entire WiGig band. Ā© 2002-2011 IEEE

    Protein Carbonylation of an Amino Acid Residue of the Na/Kā€ATPase Ī±1 Subunit Determines Na/Kā€ATPase Signaling and Sodium Transport in Renal Proximal Tubular Cells

    Get PDF
    Background We have demonstrated that cardiotonic steroids, such as ouabain, signaling through the Na/Kā€ATPase, regulate sodium reabsorption in the renal proximal tubule. By direct carbonylation modification of the Pro222 residue in the actuator (A) domain of pig Na/Kā€ATPase Ī±1 subunit, reactive oxygen species are required for ouabainā€stimulated Na/Kā€ATPase/cā€Src signaling and subsequent regulation of active transepithelial 22Na+ transport. In the present study we sought to determine the functional role of Pro222 carbonylation in Na/Kā€ATPase signaling and sodium handling. Methods and Results Stable pig Ī±1 knockdown LLCā€PK1ā€originated PYā€17 cells were rescued by expressing wildā€type rat Ī±1 and rat Ī±1 with a single mutation of Pro224 (corresponding to pig Pro222) to Ala. This mutation does not affect ouabainā€induced inhibition of Na/Kā€ATPase activity, but abolishes the effects of ouabain on Na/Kā€ATPase/cā€Src signaling, protein carbonylation, Na/Kā€ATPase endocytosis, and active transepithelial 22Na+ transport. Conclusions Direct carbonylation modification of Pro224 in the rat Ī±1 subunit determines ouabainā€mediated Na/Kā€ATPase signal transduction and subsequent regulation of renal proximal tubule sodium transport
    • ā€¦
    corecore