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The utilization of switched inductors, involving parallel charging and series discharging of inductors, is extensively embraced in diverse DC–DC converters for attaining high voltage gain; nevertheless, the stress on switch voltage and diode current escalates considerably with an increased count of inductors integrated into the switched inductors network. In the classical multistage switched inductor converter, the switch voltage aligns with the output voltage, and the diode experiences a high current as the number of stages increases. This research recommends a DC–DC multistage converter for energy conversion and high voltage gain with low stress. In this paper, a novel multistage switched inductor converter is introduced and designed to attain higher voltage gain while mitigating the stresses on switch voltage and diode current. The proposed circuit is created by replacing the standard multistage switched inductor converter's possible diodes with power switches. All of the switching devices are connected in such a way that the output voltage and input current are shared by all of the switches and diodes, respectively. As a consequence, the voltage stress on switches and the current stress on diodes are comparatively low, resulting in a high efficiency compared to a typical multistage switched inductor converter. It's interesting to note that the proposed converter and a typical multistage switched inductor converter both require the same amount of components. Different operation modes, analysis, a non‐ideal model, and a comparison of the suggested and recently constructed converters are discussed. The effectiveness and performance of the circuit are validated experimentally. [ABSTRACT FROM AUTHOR]

As a key component of high‐performance switches and routers, the packet forwarding engine (PFE) is mainly responsible for selecting the appropriate output port for tens of thousands of packets within an extremely short time frame. However, the performance of PFE is determined by the selected group membership algorithm. This paper puts forth a hybrid strategy–caching scalar‐pair and vectors routing and forwarding (CSVRF), consisting of virtual output port bitmap caching (VOPBC) and fractional‐N SVRF to address major multicast forwarding issues such as scalability by using content addressable memory. In CSVRF, a virtual output port bitmap cache is introduced, which includes the most popular combinations of output port bitmap and divides the big scalar‐pair into N sub‐groups to achieve parallel compute and the reusability of less bit‐length prime. The results demonstrate that the memory space and the forwarding latency are effectively reduced compared with previous work. In space efficiency, it only required 10% memory space compared with the original SVRF/fractional‐N SVRF, decreased 10% memory usage compared with pure VOPBC and nearly improved 1 to 4 orders of magnitude of packet processing time compared with the original SVRF and the fractional‐N SVRF respectively. [ABSTRACT FROM AUTHOR]

Background: Verbal fluency tasks are routinely used in clinical assessment and research studies of aphasia. People with aphasia produce fewer items in verbal fluency tasks. It remains unclear if their output is limited solely by their lexical difficulties and/or has a basis in their executive control abilities. Recent research has illustrated that detailed characterization of verbal fluency performance using temporal characteristics of words retrieved, clustering and switching, and pause durations, along with separate measures of executive control stands to inform our understanding of the lexical and cognitive underpinnings of verbal fluency in aphasia. Aims: To determine the locus of the verbal fluency difficulties in aphasia, we compared semantic and letter fluency trials between people with aphasia and healthy control participants using a wide range of variables to capture the performance between the two groups. The groups were also tested on separate measures of executive control to determine the relationship amongst these tasks and fluency performance. Methods & Procedures: Semantic (animal) and letter (F, A, S) fluency data for 60s trials were collected from 14 people with aphasia (PWA) and 24 healthy adult controls (HC). Variables, such as number of correct responses, clustering and switching analyses, were performed along with temporal measures of the retrieved words (response latencies) and pause durations. Participants performed executive control tasks to measure inhibitory control, mental‐set shifting and memory span. Outcomes & Results: Compared with HC, PWA produced fewer correct responses, showed greater difficulty with the letter fluency condition, were slower in getting started with the trials, showed slower retrieval times as noted in within‐ and between‐cluster pause durations, and switched less often. Despite these retrieval difficulties, PWA showed a similar decline in the rate of recall to HC, and had similar cluster size. Executive control measures correlated primarily with the letter fluency variables: mostly for PWA and in one instance for HC. Conclusions & Implications: Poorer performance for PWA is a combination of difficulties in both the lexical and executive components of the verbal fluency task. Our findings highlight the importance of detailed characterization of fluency performance in deciphering the underlying mechanism of retrieval difficulties in aphasia, and illustrate the importance of using letter fluency trials to tap into executive control processes. WHAT THIS PAPER ADDS: What is already known on the subject: PWA typically show impaired performance in verbal fluency tasks. It is debated whether this impaired performance is a result of their lexical difficulties or executive control difficulties, or a combination of both. This debate continues because previous studies have mostly used semantic fluency condition without including letter fluency condition; used a limited range of variables (e.g., number of correct responses); and not included separate executive control measures to explain the performance pattern in aphasia. This research addresses these outstanding issues to determine the specific contribution of lexical and executive control processes in verbal fluency in aphasia by including: both semantic and letter fluency conditions; a wide range of variables to identify the relative contribution of lexical and executive control mechanisms; and independent measures of executive control. What this paper adds to existing knowledge: Using the multidimensional analysis approach for verbal fluency performance from both semantic and letter fluency conditions, this is the first study to systematically demonstrate that PWA had difficulties in both lexical and executive control components of the task. At the individual level, PWA had greater difficulty on the letter fluency condition compared with semantic fluency. We observed significant correlations between the executive control measures and verbal fluency measures primarily for the letter fluency condition. This research makes a significant contribution to our understanding of lexical and executive control aspects in word production in aphasia. What are the potential or actual clinical implications of this work?: From a clinical perspective, this research highlights the importance of using a full range of verbal fluency and executive control measures to tap into the lexical as well as executive control abilities of PWA, and also the utility of using letter fluency to tap into the executive control processes in PWA. [ABSTRACT FROM AUTHOR]

In this paper, Artificial Neural Networks (ANNs) for diagnosing multiple open‐switch faults in three‐phase PWM (Pulse Width Modulation) converters are designed. For single and double open‐switch faults in the converters, there are 21 types of fault modes, causing distorted phase currents. Since these abnormal currents can induce secondary faults in peripherals, the open‐fault diagnosis is essentially required. In this paper, a two‐step technique based on ANNs is utilized for the diagnosis of the multiple open‐switch fault. First, dc and harmonic components of the currents are extracted by using an ADALINE (Adaptive Linear Neuron). In the first step, the ANN categorizes fault modes into six sectors by using dc components in the three‐phase plane. In the second step, the ANN localizes fault modes by using dc components and the ratio of d–q axes currents THDs (Total Harmonics Distortions) in each sector. Especially, both switches open‐faults in the same legs are localised by counting the sampled zero current of the fault currents. The proposed two‐step technique allows a simple design of the ANNs for the diagnosis, and a short execution time about 22 s. Simulations and experiments for a 3.7 kW three‐phase PWM converter confirmed the validity of the proposed diagnostic method. [ABSTRACT FROM AUTHOR]

This paper presents a novel converter topology for six-phase switched reluctance motor (SRM) drives, which reduces the number of switches and diodes by half, compared with the conventional asymmetric half-bridge (AHB) converter, and needs no additional energy storage component. A dynamic model of a six-phase SRM is developed in the MATLAB/SIMULINK environment and conventional control technique is applied to the proposed converter, demonstrating successful operation with modified conventional current control technique, lower converter losses, and higher system efficiency compared with the AHB converter. Furthermore, a direct torque control (DTC) method has been proposed for the novel converter to further reduce the torque ripple. Experimental tests comparing the proposed converter with the AHB are described and verify the predictions of the simulations. [ABSTRACT FROM AUTHOR]

Field-programmable gate array (FPGA)-based simulation system is applied in real-time electromagnetic transient (EMT) simulation for small time-step simulation. However, the FPGA-based simulation system requires handcrafted hardware description language (HDL) and significant design efforts. This paper explores FPGA-based EMT real-time simulation system design using high-level synthesis (HLS) technology to accelerate the design process and improve the flexibility, because high-level language can be transferred into HDL using HLS. Furthermore, loop unroll and pipeline optimisation directives are analysed and applied for HLS to improve the computation speed of the components. The system can simulate various components, including switches, R-L-C, voltage sources, current sources, and transmission lines. Especially, the system adopting double-precision floating-point calculation can support the network with 74 nodes and achieve 2 us for each small time step on Xilinx Virtex7-690 T FPGA. Comparison of simulation results from offline simulation tools with those from the proposed simulation system validates the correctness of the FPGA-based EMT simulation system using HLS technology. [ABSTRACT FROM AUTHOR]

The new photonics applications of liquid crystals are highligthed: LC photonics elements for passive optical network systems, such as LC switches, sensors, lenses, LC light converters, optically and electrically rewritable E-paper. Special attention will be paid to photoalignment technology for LC photonics and emergent display devices. [ABSTRACT FROM AUTHOR]

In this second part of our review article on the preferred screw sense and interconversion of peptide helices, we discuss the most significant computational and experimental data published on helices formed by the most extensively investigated categories of noncoded α-amino acids. They are as follows: (i) N-alkylated Gly residues (peptoids), (ii) C α-alkylated α-amino acids, (iii) C α, β- sp2 configurated α-amino acids, and (iv) combinations of residues of types (ii) and (iii). With confidence, the large body of interesting papers examined and classified in this editorial effort will stimulate the development of helical peptides in many diverse areas of biosciences and nanosciences. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, several microwave devices using a ferromagnetic composite demonstrate great tunability under weak magnetizing field conditions. Indeed, a tunable bandstop of 50% tunability and phase shifters of 35°/dB figure of merit around 3 GHz and 7.8°/dB in the X-band are obtained when a 250 Oe dc magnetic field is applied. Moreover, a magnetic switch near 25 dB isolation and less than 1 dB insertion losses is realized. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 272–276, 2001. [ABSTRACT FROM AUTHOR]