Linearized large signal modeling, analysis, and control design of phase-controlled series-parallel resonant converters using state feedback

This paper proposes a linearized large signal state-space model for the fixed-frequency phase-controlled series-parallel resonant converter. The proposed model utilizes state feedback of the output filter inductor current to perform linearization. The model combines multiple-frequency and average state-space modeling techniques to generate an aggregate model with dc state variables that are relatively easier to control and slower than the fast resonant tank dynamics. The main objective of the linearized model is to provide a linear representation of the converter behavior under large signal variation which is suitable for faster simulation and large signal estimation/calculation of the converter state variables. The model also provides insight into converter dynamics as well as a simplified reduced order transfer function for PI closed-loop design. Experimental and simulation results from a detailed switched converter model are compared with the proposed state-space model output to verify its accuracy and robustness

IP3 receptors and store-operated Ca2+ entry: a license to fill.

Inositol 1,4,5-trisphosphate receptors (IP3Rs) are widely expressed intracellular Ca2+ channels that evoke large local increases in cytosolic Ca2+ concentration. By depleting the ER of Ca2+, IP3Rs also activate store-operated Ca2+ entry (SOCE). Immobile IP3Rs close to the plasma membrane (PM) are the only IP3Rs that respond to physiological stimuli. The association of these 'licensed' IP3Rs with the ER-PM junctions where STIM interacts with Orai PM Ca2+ channels may define the autonomous functional unit for SOCE. Ca2+ entering cells through SOCE can be delivered directly to specific effectors, or it may reach them only after the Ca2+ has been sequestered by the ER and then released through IP3Rs. This 'tunnelling' of Ca2+ through the ER to IP3Rs selectively delivers Ca2+ to different effectors.Wellcome Trust BBSR

IoTility:Architectural Requirements for Enabling Health IoT Ecosystems

The increasing ubiquity of the Internet of Things (IoT) has the potential to drastically alter the way healthcare systems are utilized at home or in a care environment. Smart things offer new ways to assist in general patient wellness, such as promoting an active and healthy lifestyle and simplifying treatment management. We believe smart health things bring new requirements not typically addressed in traditional IoT systems, and that an architecture targeting these devices must address such requirements to fully utilize their potential and safe usage. We believe such an architecture will help improve adoption and efficacy, closing gaps between the variety of emerging health IoT systems. In this paper, we present a number of requirements we consider integral to the continued expansion of the digital health IoT ecosystem (Health IoT). We consider the current landscape of IoT in relation to these requirements and present solutions that address two pressing requirements: 1) democratizing mobile health apps (giving users control and ownership over their app and data), and 2) making mobile apps act and behave like any other thing in an IoT. We present an implementation and evaluation of these Health IoT requirements to show how health-specific solutions can drive and influence the design of more generalized IoT architectures

Image retrieval based on swarm intelligence

To keep pace with the development of modern technology in this information technology era, and the immense image databases, whether personal or commercial, are increasing, is requiring the management of these databases to strong and accurate systems to retrieve images with high efficiency. Because of the swarm intelligence algorithms are great importance in solving difficult problems and obtaining the best solutions. Here in this research, a proposed system is designed to retrieve color images based on swarm intelligence algorithms. Where the algorithm of the ant colony optimization (ACOM) and the intelligent water drop (IWDM) was used to improve the system's work by conducting the clustering process in these two methods on the features extracted by annular color moment method (ACM) to obtain clustered data, the amount of similarity between them and the query image, is calculated to retrieve images from the database, efficiently and in a short time. In addition, improving the work of these two methods by hybridizing them with fuzzy method, fuzzy gath geva clustering algorithm (FGCA) and obtaining two new high efficiency hybrid algorithms fuzzy ant colony optimization method (FACOM) and fuzzy intelligent water drop method (FIWDM) by retrieving images whose performance values are calculated by calculating the values of precision, recall and the f-measure. It proved its efficiency by comparing it with fuzzy method, FGCA and by methods of swarm intelligence without hybridization, and its work was excellent

A PWM current source-based DC transmission system for multiple wind turbine interfacing

A pulsewidth modulation (PWM) current source wind energy conversion system based on a parallel configuration for high voltage direct current application is proposed. A comparison between the parallel and series configurations for current source-based systems is investigated, which shows the merits of the proposed system. A new control technique for the PWM current source inverter is proposed. It can effectively control the average dc-link voltage with a feed-forward loop, while independently controlling reactive power according to grid code requirements. The system simulation confirms the performance of the proposed system with no interaction between wind turbine modules and satisfying performance with grid integration. Practical implementation further verifies the proposed inverter control. Finally, a brief comparison between conventional line-commutated converter-based systems and the proposed PWM current source converter-based system is presented

The effects of aging on hepatic microsomal scaling factor and hepatocellularity number in the horse

Scaling factor values for the in vitro-in vivo extrapolation of hepatic metabolic clearance for xenobiotics have not yet been determined in horses. Scaling factors were determined by comparing the total protein and or CYP P450 content in microsomes and cryopreserved hepatocytes against the content in the liver. Microsomal protein per gram of liver (MPPGL) and hepatocellularity number per gram of liver (HPGL) using CYP P450 content method ranged 41 - 73 mg/gram of liver (mean= 57 mg/gram of liver, n=39) and 146 - 320 × 106 cells/g of liver (mean = 227× 106 cells/g of liver, n=18), respectively; and 156 - 352 × 106 cells/g of liver (mean = 232× 106 cells/g of liver) using total protein method. A non-monotonic and inverse relationship between age and MPPGL and HPGL, respectively, was observed. Between 1 and 20 years of age the liver cell size decreases as age increases. Subsequently, the cell size increases until the hepatocytes of the oldest horses approached the size found in the youngest horses. Hepatocyte density was inversely related to the size of the hepatocytes. This study provides the first extensive and comprehensive data demonstrating the relationship between the size of hepatocytes and HPGL in any species

Extracellular Glutamate: Functional Compartments Operate in Different Concentration Ranges

Extracellular glutamate of glial origin modulates glial and neuronal glutamate release and synaptic plasticity. Estimates of the tonic basal concentration of extracellular glutamate range over three orders of magnitude (0.02–20 μM) depending on the technology employed to make the measurement. Based upon binding constants for glutamate receptors and transporters, this range of concentrations translates into distinct physiological and pathophysiological roles for extracellular glutamate. Here we speculate that the difference in glutamate measurements can be explained if there is patterned membrane surface expression of glutamate release and transporter sites creating extracellular subcompartments that vary in glutamate concentration and are preferentially sampled by different technologies

Discovering SUSY in the first LHC run

4 páginas, 1 figura.-- Trabajo presentado a la Fifth Conference on Physics at LHC celebrada en Hamburgo (Alemania) del 7 al 12 de junio de 2010.We analyze the potential of the first LHC physics run, assuming 1 fb−1 at ps = 7 TeV, to discover Supersymmetry (SUSY). The results are based on SUSY parameter fits following a frequentist approach. They include the experimental constraints from electroweak precision data, (g − 2)μ, B physics and cosmological data. The two SUSY models under consideration are the constrained MSSM (CMSSM) with universal soft supersymmetry-breaking mass parameters, and a model with common non-universal Higgs mass parameters in the superpotential (NUHM1). We find that large parts of the regions preferred at the 68% C.L. are accessible to early LHC running.Work supported in part by the European Community’s Marie-Curie Research Training Network under contract MRTN-CT-2006-035505 ‘Tools and Precision Calculations for Physics Discoveries at Colliders’ (HEPTOOLS).Peer reviewe

Construction and Characterization of a cDNA Library from Wheat Infected with Fusarium graminearum Fg 2

Total RNA from wheat spikes infected with F. graminearum Fg2 was extracted and the mRNA was purified. Switching Mechanism at 5′ end of the RNA Transcript (SMART) technique and CDS Ill/3′ primer were used for first-strand cDNA synthesis using reverse transcriptase by RT-PCR. Primer extension polymerase chain reaction was used to construct the double-strand cDNA that was digested by proteinase K, then by Sfi I and fractionated. cDNAs longer than 0.5 kb were collected and ligated to λTriplEx2 vector followed λ phage packaging reaction and library amplification. The qualities of both unamplified and amplified cDNA libraries were strictly checked by conventional titer determination. One hundred and sixty five plaques were randomly picked and tested using PCR with universal primers derived from the sequence flanking the vector. A high quality cDNA library from wheat spikes that have been infected by F. graminearum was successfully constructed

Hybrid multilevel converter with cascaded H-bridge cells for HVDC applications : operating principle and scalability

Hybrid multilevel converters are contemplated in an attempt to optimize the performance of voltage source converters in terms of magnitude of semiconductor losses and converter footprint, and to achieve additional features such as dc short circuit proof, which is essential for a high integrity multiterminal HVDC grid. Therefore, this paper considers an emerging hybrid cascaded converter that offers the dc side short circuit proof feature at reduced loss and footprint compared to the existing multilevel and other hybrid converters. Its operating principle, modulation, and capacitor voltage balancing strategies are described in detail. Furthermore, hybrid converter scalability to high voltage applications is investigated. The validity of the modulation and capacitor voltage strategy presented are confirmed using simulation and experimentation. The hybrid cascaded converter is extendable to a large number of cells, making it applicable to high voltage applications, and operation is independent of modulation index and power factor. On these ground, the converter is expected to be applicable for both real and reactive power applications