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By adjusting the ellipticity of counter-rotating polarized few-cycle pulses for non-collinear high order harmonic generation, we obtain full control of polarization states of isolated attosecond pulses for the first time.
This paper investigates the characteristics of both efficiency and voltage regulation of a practical single-phase distribution transformer when the shape and dimension of the laminated core are varied. Typically, the iron core of a traditional transformer is composed of E- and I-shape laminations to reduce core loss. The reluctance for the magnetic-flux path inside the iron core of a transformer is...
This paper proposes a single-stage high-power-factor asymmetrical half-bridge AC-DC converter for power factor correction. The proposed converter is developed by integrating an asymmetrical half-bridge DC-DC converter with a set of coupled inductors and a blocking diode to achieve the single-stage AC-DC conversion with the buck-boost type power factor correction. By using the coupled inductors, the...
This design provides an automatic charging voltage and current adjustment through the wireless message transmission of a smart charger. The smart battery charging voltage and current can be adjusted according to different ambient temperatures to provide a safe operation. In addition, the current battery status and warning message can be transmitted through wireless message transmission to a smartphone...
Harmonics are commonly encountered in the unbalanced three-phase power system. They can cause oscillation of the nominal frequency, which damages the stability of the electrical system. In this paper, an adaptive batch-mode frequency estimator is devised to monitor this variation. After converting the three-phase waveforms into a complex-valued signal via αβ-transformation, a high-resolution spectral...
The study is to evaluate computed tomography (CT) and magnetic resonance imaging (MRI) utilization patterns among health care related patients and other patients. Methods: The data for 2011 to 2013 were collected from the National Health Insurance Research Database (NHIRD) published by the National Health Research Institutes in Taiwan. Propensity score matching was used to control the medical professional...
We experimentally demonstrate angularly and temporally isolated counter-rotating circularly polarized attosecond pulses at 33 eV. The pulse contrast and circular polarization of the beams are fully characterized by a field autocorrelator and an EUV polarimeter.
With rapid development and extensive usage of sensors technology, large volumes of sensor data are generated. How to effectively store and process sensor data has been widely concerned. However, with the characteristics of chronological order, large volume and high concurrency, there are a number of difficulties, in particular, hot spot problem, data scatter problem and high concurrent transaction...
The work is mainly to use anionic polymerization to prepare polyisoprene, and then functionalize the end of polyisoprene as an acrylic functional group which (PIMA) can undergo radical copolymerization [1]. We choose methyl methacrylate (MMA) and poly(ethylene glycol) methyl ether methacrylate(PEGMA) as comonomers in radical copolymerization with PIMA in order to add viscosity and hydrophilicity to...
In this paper, we investigate a binary two-way diffusion channel from an information theoretical perspective. Molecule harvesting is considered by which molecules can be reused by the receiver for subsequent transmissions. An outer bound of the capacity region for the general case and inner bounds for specific cases are derived. With the proposed outer bound, we show that no signaling rate is achievable...
Packing polygonal objects to be cut in fiber or leather densely for efficient use of material is important to automatic die-cutting machine tools. Prior to computing a tight pack of objects in a given area of material, proper gaps among packed objects should be firstly reserved to prevent over-cutting on the edges of neighboring objects by a die. To maintain object gaps for packing, we propose a new...
A modified asymmetrical half-bridge flyback converter (AHBFC) to fulfill the single-stage buck-type AC-DC adaptor for notebook application is proposed in this paper. The modified AHBFC is obtained from the integration of a buck converter and a conventional AHBFC. The modified AHBFC is operated in the discontinuous conduction mode to achieve the high input power factor to meet the required regulations...
This paper presents a Doppler radar with metamaterial-based leaky-wave antennas for the hand-gesture sensing application. Since the antenna main beam of the developed radar can be arbitrarily pointed to a known azimuth angle, the hand gesture moving in the decomposed orthogonal directions can be successfully detected. In addition, the phase information caused by the hand gesture is accurately retrieved...
We demonstrate that phase-matching cutoff of high-order-harmonic generation can be extended by only modifying the geometric parameter and fundamental beam profile, resulting in a 400-times flux enhancement at 65eV in argon using truncated 0.8 μm pulses.
Mate-pair sequencing is a technology for sequencing two ends of long DNA fragments, which has been widely used in genome scaffolding. Although the cost of mate-pair sequencing is now affordable, its accuracy has been limited by the lower quality and contamination. The 3rd generation sequencing is able to generate long reads for genome scaffolding. However, the error rates and cost are still too high...
In this paper, Electrostatic-Discharge (ESD) reliability study of 45-V HV pLDMOS devices with the source-side discrete islands is investigated. A pure pLDMOS transistor is always frail in ESD harms (It2= 0.107-A). However, if a pLDMOS device with two embedded SCRs (drain side npn-arranged); the corresponding It2 current can be upgraded to 0.644-A. Furthermore, as a pLDMOS-SCR (npn-arranged stripe...
This research aims for developing a simple but novel hybrid electric scooter (HES) for enhancing output performance compared to electric scooters and engine scooters. The mechanical system, mechatronics, and vehicle control unit (VCU) were designed and implemented on a 125 c.c. engine vehicle. For the mechanical modification, it mainly includes: 1) integrating a 1.5kW wheel motor on the hub with a...
An evaluation of electrostatic-discharge (ESD) reliability by changing the source-end layout of 45-V HV pLDMOS devices is investigated in this paper. After testing and systematic analysis, it can be found that a traditional pLDMOS sample is always very weak in ESD issues (It2= 0.107-A). At the same time, if a pLDMOS with a stripe type embedded SCR (p-n-p-arrangement in the drain-end); the corresponding...
Over the last few decades, there has been a growing interest in technology assisted multimedia learning. The purpose of this study was to develop an online multimedia learning system, TEDQuiz, for English language learners to practice their listening skills. The system is comprised of an easy-to-use browser extension and a personalized online learning management platform. This can help learners to...
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