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Hysteretic Nonlinearity Observer Design Based on Kalman Filter for Piezo-actuated Flexible Beams with Control Applications

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International Journal of Automation and computing 2014年第6期11卷 627-634页

作者： Teerawat Sangpet Suwat Kuntanapreeda Rüdiger schmidt Department of Mechanical and Aerospace Engineering King Mongkut's University of Technology North Bangkok Bangkok 10800 Thailand Institute of General Mechanics RWTH Aachen University Aachen D-52056 Germany

Piezoelectric actuators fundamentally possess hysteresis behavior. Estimation of the hysteresis is usually demanded for enhancing the performance of piezo-actuated systems. This paper presents an observer-based scheme to estimate the hysteresis in piezo—actuated flexible beams. The observer is based on a nonlinearity observer method. The discrete-time Kalman-filter algorithm is adopted for determination of the observer gains. The major advantages of the presented scheme include ease of implementation and robustness to uncertainty of hysteresis parameters. Simulation results demonstrate that the observer is able to estimate the hysteresis efficiently and has better robustness compared to the previous scheme existing in the literature. The present scheme was also successfully applied to a real-life system. Moreover, a control application example is included to demonstrate the effectiveness of the scheme.

关键词： Observers piezoelectric actuator Kalman filter hysteresis hysteresis compensation flexible beam

Greenhouse gases fluxes and soil thermal properties in a pasture in central Missouri

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Journal of Environmental Sciences 2010年第7期22卷 1029-1039页

作者： Nsalambi Vakanda Nkongolo Shane Johnson Kent schmidt Frieda Eivazi Department of Agriculture and Environmental Sciences College of Agriculture and Natural Science Lincoln University Harvard Forest Faculty of Arts and Sciences Harvard University

Fluctuations of greenhouse gases emissions and soil properties occur at short spatial and temporal scales, however, results are often reported for larger scales studies. We monitored CO2, CH4, and N2O fluxes and soil temperature （T）, thermal conductivity （K）, resistivity （R） and thermal diffusivity （D） from 2004 to 2006 in a pasture. Soil air samples for determination of CO2, CH4 and N2O concentrations were collected from static and vented chambers and analyzed within two hours of collection with a gas chromatograph. T, K, R and D were measured in-situ using a KD2 probe. Soil samples were also taken for measurements of soil chemical and physical properties. The pasture acted as a sink in 2004, a source in 2005 and again a sink of CH4 in 2006. CO2 and CH4 were highest, but N2O as well as T, K and D were lowest in 2004. Only K was correlated with C02 in 2004 while T correlated with both N2O （r = 0.76, p = 0.0001） and CO2 （r = 0.88, p = 0.0001） in 2005. In 2006, all gases fluxes were significantly correlated with T, K and R when the data for the entire year were considered. However, an in-depth examination of the data revealed the existence of month-to-month shifts, lack of correlation and differing spatial structures. These results stress the need for further studies on the relationship between soil properties and gases fluxes. K and R offer a promise as potential controlling factors for greenhouse gases fluxes in this pasture.

关键词： greenhouse gases soil thermal properties fluxes

A review on glass welding by ultra-short laser pulses

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International Journal of Extreme Manufacturing 2019年第4期1卷 1-10页

作者： Kristian Cvecek Sarah Dehmel Isamu Miyamoto Michael schmidt Institute of Photonic Technologies Friedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany SAOT—Erlangen Graduate School in Advanced Optical Technologies Friedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany blz—Bayerisches Laserzentrum GmbH ErlangenGermany Osaka University OsakaJapan

Glass welding by ultra-short pulsed(USP)lasers is a piece of technology that offers high strength joints with hermetic *** joints are typically formed in glass that is transparent to the laser by exploiting nonlinear absorption effects that occur under extreme *** the temperature reached during the process is on the order of a few 1000°C,the heat affected zone(HAZ)is confined to only tens of *** is this controlled confinement of the HAZ during the joining process that makes this technology so appealing to a multitude of applications because it allows the foregoing of a subsequent tempering step that is typically essential in other glass joining techniques,thus making it possible to effectively join highly heat sensitive *** this work,we give an overview on the process,development and applications of glass welding by USP lasers.

关键词： USP glass welding ultra-short pulsed laser processing brittle materials glass joining

Nano energy for miniaturized systems

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Nano Materials Science 2021年第2期3卷 107-112页

作者： Minshen Zhu Feng Zhu Oliver G.schmidt Institute for Integrative Nanosciences Leibniz IFW Dresden01069DresdenGermany State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences130022ChangchunChina Material Systems for Nanoelectronics Chemnitz University of Technology09107ChemnitzGermany Center for Materials Architectures and Integration of Nanomembranes(MAIN)Chemnitz University of Technology09126ChemnitzGermany School of Science Dresden University of TechnologyGermany

Skin mountable electronic devices are in a high-speed development at the crossroads of materials science,electronics,and computer *** functions,such as sensing,actuating,and computing,are integrated into a soft electronic device that can be firmly mounted to any place of human *** advanced electronic devices are capable of yielding abilities for us whenever they are needed and even expanding our abilities beyond their natural *** the great promise of skin mounted electronic devices,they still lack satisfactory power supplies that are safe and *** Perspective discusses the prospects of the development of energy storage devices for the next generation skin mountable electronic devices based on their unique requirements on flexibility and miniaturized size.

关键词： Micro-energy-storage devices Wearability Flexibility Electronics

DeepFilter: A Deep Learning Based Variant Filter for VarDict

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清华大学学报:自然科学版(英文版) 2023年第4期28卷 665-672页

作者： Hao Zhang Zekun Yin Yanjie Wei Bertil schmidt Weiguo Liu School of Software Shandong UniversityJinan 250100China Shenzhen Research Institute of Shandong University Shenzhen 518057China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China Institute for Computer Science Johannes Gutenberg UniversityMainz 55128Germany

With the development of sequencing technologies,somatic mutation analysis has become an important component in cancer research and *** is a commonly used somatic variant caller for this *** the heuristic-based VarDict algorithm exhibits high sensitivity and versatility,it may detect higher amounts of false positive variants than callers,limiting its clinical *** address this problem,we propose DeepFilter,a deep-learning based filter for VarDict,which can filter out the false positive variants detected by VarDict *** approach trains two models for insertion-deletion mutations(InDels)and single nucleotide variants(SNVs),*** show that DeepFilter can filter at least 98.5%of false positive variants and retain 93.5%of true positive variants for InDels and SNVs in the commonly used tumor-normal paired *** code and pre-trained models are available at https://***/LeiHaoa/DeepFilter.

关键词： variant filter deep learning somatic variant

On the role of cobalt carbidization in higher alcohol synthesis over hydrotalcite-based Co-Cu catalysts

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Chinese Journal of Catalysis 2019年第11期40卷 1731-1740页

作者： Janine Nebel Stefan schmidt Qiushi Pan Katrin Lotz Stefan Kaluza Martin Muhler Laboratory of Industrial Chemistry Ruhr-University Bochum Universitasstr. 150 44780 Bochum Germany Fraunhofer Institute for Environmental Safety and Energy Technology UMSICHT Osterfelder Str. 3 46047 Oberhausen Germany

Co-Cu-based catalysts are widely applied in higher alcohol synthesis (HAS) from synthesis gas. Although the nature of the active sites is still not fully understood, the formation of Co2C under HAS conditions seems to play a major role. A CO pretreatment procedure was developed allowing a systematic investigation of the influence of cobalt carbidization on the structural properties and catalytic performance of the catalysts. By exposing the catalyst to a CO-containing atmosphere prior to HAS, Co enrichment of the catalyst surface occurred followed by carbide formation. This surface modification decreased the formation of hydrocarbons and enhanced the formation of C2+OH. The catalyst pretreated with CO at 20 bar achieved the highest selectivity to ethanol and the lowest hydrocarbon selectivity.

关键词： Higher alcohol synthesis Co-Cu catalyst Co_(2)C CO pretreatment

Paving small matrices and the Kadison-Singer Extension Problem Ⅱ—computational results

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Science China Mathematics 2011年第11期54卷 2463-2472页

作者： schmidt Dieter WEISS Gary ZARIKIAN Vrej Department of Mathematics University of Cincinnati Cincinnati OH 45221 USA Department of Mathematics United States Naval Academy Annapolis MD 21402 USA

This article is part exposition of a recent rather technical paper of the last two authors on matrix pavings related to the 1959 Kadison-Singer Extension Problem and part a report on further computational results providing new bounds on the paving parameters for classes of small matrices investigated there and subsequently. A website maintained by the authors provides to all interested the matrices experimentally discovered that yield these bounds along with the proprietary MATLAB software with simple operational directions to load them, pave them, and perform paving searches. The convergence to 1 or not of the infinite sequences of these paving parameters in most cases is equivalent to the Kadison-Singer Extension Problem, and in all cases convergence to 1 negates the problem. The last two sections describe the search process and an interpretation of the data integrated with the results of the precursor to this paper.

关键词： Kadison-Singer Extension Problem Anderson's Paving Problem

Editorial for a special issue“Nano energy materials and devices for miniaturized electronics and smart systems”

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Nano Materials Science 2021年第2期3卷 105-106页

作者： Feng Zhu Oliver G.schmidt Changchun Institute of Applied Chemistry China Leibniz IFW DresdenGermany Chemnitz Chemnitz University of Technology Germany

The Smart Era urgently demands small-size, low-energy consuming and multi-functional devices which can satisfy versatile application scenarios, including autonomous systems, wireless sensor networks,biomedical equipment, wearable gadgets, and the Internet of *** overwhelming trend has drawn much attention and stimulates intensive collaborative efforts spanning diverse fundamental and applied research related to energy generation-harvesting-storage-managementapplications at the small scale. For instance, on one hand.

关键词： energy smart versatile

Lost in transition： Forest transition and natural forest loss in tropical China

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Plant Diversity 2017年第3期39卷 149-153页

作者： Deli Zhai Jianchu Xu Zhicong Dai Dietrich schmidt-Vogt Centre for Mountain Ecosystem Studies (CMES) Kunming Institute of Botuny (CAS) Lanhei Road 132 Kunming 650201 China World Agroforestry Centre (ICRAF) Central and East Asia Office Lanhei Road132 Kunming 650201 China Instituteof-Environment and Ecology School of the Environment and Safety Engineering fiangsu University No. 301 Xuefu Road Zhenjiang 212013 China Mountain Societies Research Institute University of Central Asia 138 Toktogul Street Bishkek 720001 Kyrgyzstan

The term forest transition refers to a change in forest cover over a given area from a period of net forest area loss to a period of net gain. Whether transitioning from deforestation to reforestation can lead to improved ecosystem services, depends on the quality and characteristics of the newly established forest cover. Using publicly available data, we examine forest transition in two regions of tropical China: Hainan Island and Xishuangbanna. We found that the overall increase of forest cover in both areas during the1980 s was due to an increase in plantation forests rather than to increases in the area covered by natural forest. We also found a time lag between the increase in overall forest cover and an increase in natural forest. On Hainan Island, natural forest continued to decline beyond the point in time when overall forest cover had started to increase, and only began to recover ten years after the turning point in 1978. In Xishuangbanna, where the transition point occurred ten years later, the decline of natural forest cover is still going on. These divergent trends underlying forest transition are concealed by the continued practice to apply the term "forest" broadly, without distinguishing between natural forests and planted *** to the use of undiscriminating terminology, the loss of natural forest may go unnoticed, increasing the risk of plantation forests displacing natural forests in the course of forest transition. Our findings are important for programs related to forest management and ecosystem services improvement, including reforestation and Payments for Ecosystem Services programs.

关键词： Deforestation Forest transition Rubber plantation Time lag Tropical China