A Study on Pulsed Power Supply based on Separate Excitation

© ASEE 2007Regular power supply cannot be used for some special applications such as discharging plasma generator, air purification system, medical discharging equipment, etc. Instead, a special low-power high-voltage pulsed power supply is required. In this paper, the design and simulation of a separate excited pulse power supply are proposed. The power supply can produce high-voltage small-current pulses adaptive to different loads. The working principle of the power supply is analyzed. A comparison between this power supply and other pulsed power supply based on capacitance energy storage is discussed. The circuit implementation of power supply is proposed. The key component for the power supply, pulse transformer, as well as other components is studied in detail. Based on the analysis, an optimized design of the power supply is proposed. Computer simulation is used to verify the performance of the designed power supply, such as the output characteristics under different load resistances, the pulse frequency and the duty ratio. Simulation results demonstrate the effectiveness of the designed power supply. Some possible performance improvements on the power supply are also suggested. The designed power supply can satisfy the requirements for commercial applications such as plasma generation and air purification system

Balance-approach For Mechanical Properties Test of Micro Fabricated Structure

Copyright 1997 Society of Photo Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.A simple and effective method using a balance to measure micro force and corresponding deflection is presented. The method is proved to be very practical in testing the force-deflection behavior of silicon cantilever, in which the Young’s modulus of the material can be calculated, and in investigating the static performance of bulk micromachined capacitive accelerometers. The balance approach for micro force-displacement measurement is very attractive for its easiness in operation, low cost and higher resolution.http://dx.doi.org/10.1117/12.28449

Model-based Offline Policy Optimization with Adversarial Network

Model-based offline reinforcement learning (RL), which builds a supervised transition model with logging dataset to avoid costly interactions with the online environment, has been a promising approach for offline policy optimization. As the discrepancy between the logging data and online environment may result in a distributional shift problem, many prior works have studied how to build robust transition models conservatively and estimate the model uncertainty accurately. However, the over-conservatism can limit the exploration of the agent, and the uncertainty estimates may be unreliable. In this work, we propose a novel Model-based Offline policy optimization framework with Adversarial Network (MOAN). The key idea is to use adversarial learning to build a transition model with better generalization, where an adversary is introduced to distinguish between in-distribution and out-of-distribution samples. Moreover, the adversary can naturally provide a quantification of the model's uncertainty with theoretical guarantees. Extensive experiments showed that our approach outperforms existing state-of-the-art baselines on widely studied offline RL benchmarks. It can also generate diverse in-distribution samples, and quantify the uncertainty more accurately.Comment: Accepted by 26th European Conference on Artificial Intelligence ECAI 202

Analysis on Efficiency of Slot-Cutting Around RC Frame Joint for “Strong Column and Weak Beam” Engineering Design

AbstractA numerical model was established with Adina software for beam-column joint on a reinforced concrete frame. The results for the traditional joint and that for the joint with slot around were compared. It is shown that the stress in the reinforce bar for slab close to beam will increase significantly with the applied top drift in horizontal direction, and less for far from the beam. It is also shown that for the joint with slot around, the yielding time of column bar will shift to a later time, while number of cracks on column becomes less. The time interval between the occurrence of plastic pivot on beam and on column becomes longer. The occurrence of column plastic pivot on the first floor would be delayed, which exhibits a failure type closer to the ductile mode

Molecular characterization and phylogenetic analysis of one omega-gliadin gene from aegilops speltoides l.

Gliadins, as the major components of wheat storage proteins, determine the extensibility properties of dough and have important effects on flour processing quality. Wheat related species carries potential storage protein gene resources for quality improvement. In this study, we isolated and characterized the first complete omega-gliadin gene Omega-AS from Aegilops speltoides L. (2n = 2x = 14, SS) by allelic-specific PCR and investigated its phylogenetic relationships among Triticum and Aegilops species. Molecular structure showed that Omega-AS gene consisted of 1122 bp encoding 373 amino acid residues with deduced molecular mass 41379.21 Da. Omega-AS gene was exceptionally rich in prolines and glutamines with fewer methionine and no cysteine. Sequence characterization and epitope analysis showed that three epitopes QQPIPVQPQQ, TQPQQPTPIQ and IQPQQPFPQQ were absent in Omega-AS gene encoded protein, indicating its potential value for wheat quality improvement with less toxic, or no toxic peptides. Phylogenetic analysis revealed that Omega-AS was closely related to gliadin genes of wheat and related species and its divergence from bread wheat was more recently (less than 1.243 MYA). Heterologous expression showed that Omega-AS gene could successfully express with a high level in E. coli under the control of T-7 promoter. The transcription expression pattern of Omega AS gene during grain development detected by qRT-PCR revealed that the highest expression level occurred at 17 days post anthesis