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矩形边界限定形式的感应电机低开关频率预测控制研究

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中国电机工程学报 2024年第8期44卷 3278-3286,I0029页

作者：齐昕张家宁 HOLTZ joachim 田柏轩任佳仕王辰宇周珂北京科技大学机械工程学院北京市海淀区100083 伍珀塔尔大学电机与驱动实验室德国伍伯塔尔42119 北京科技大学顺德研究生院广东省佛山市528399 北京科技大学高等工程师学院北京市海淀区100083

圆形边界限定形式预测控制对电流畸变的限定在各方向均相同,无法通过增大边界圆半径进一步降低开关频率。因此,该文提出一种矩形边界限定形式的预测控制方法。首先,深入分析感应电机数学模型,发现感应电机转子子系统的低通物理特性,以... 详细信息

圆形边界限定形式预测控制对电流畸变的限定在各方向均相同,无法通过增大边界圆半径进一步降低开关频率。因此,该文提出一种矩形边界限定形式的预测控制方法。首先,深入分析感应电机数学模型,发现感应电机转子子系统的低通物理特性,以及励磁电流波动对电磁转矩的影响不显著;其次,利用该特性,将限定边界改为矩形,对转矩电流与励磁电流进行独立约束,适度增加励磁电流畸变允许限值,扩大电流轨迹运动范围,延长开关状态切换时长;再次,探究电流矢量梯度同边界约束间的数学关系,提出该方法下电压矢量筛选与寻优准则,筛选出最优矢量;最终,进行实验对比。实验结果证明,在相同系统动态特性和转矩波动下,相较于圆形边界限定策略,矩形边界限定策略可以进一步降低开关频率。

关键词：矩形边界低开关频率预测控制感应电机

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The effect of Laves phases and nano-precipitates on the electrochemical corrosion resistance of Mg-Al-Ca alloys under alkaline conditions

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Journal of Magnesium and Alloys 2024年第6期12卷 2447-2461页

作者： Markus Felten Veronika Chaineux Siyuan Zhang Ali Tehranchi Tilmann Hickel Christina Scheu Joshua Spille Marta Lipińska-Chwałek joachim Mayer Benjamin Berkels Marcus Hans Imke Greving Silja Flenner Sandra Sefa Daniela Zander Chair of Corrosion and Corrosion Protection RWTH Aachen UniversityAachen 52072 Germany Max-Planck-Institut für Eisenforschung GmbH Düsseldorf 40237 Germany Central Facility for Electron Microscopy RWTH Aachen UniversityAachen 52074 Germany Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons Forschungszentrum Jülich GmbHJülich 52428Germany Mathematical Image and Signal Processing Aachen Institute for Advanced Study in Computational Engineering ScienceRWTH Aachen UniversityAachen 52062 Germany Materials Chemistry RWTH Aachen UniversityAachen 52074 Germany Institute of Materials Physics Helmholtz-Zentrum HereonGeesthacht 21502 Germany

The electrochemical corrosion mechanisms of Mg alloys were extensively studied in previous investigations of different chemical com-positions,modified surface states and various electrolyte ***,recent research focused on the active state of Mg dissolution,leading to unresolved effects of secondary phases adjacent to a stableα-solid solution passive *** present study investigates the fundamental electrochemical corrosion mechanisms of three different Laves phases with varying phase morphologies and phase fractions in the passive state of Mg-Al-Ca *** microstructure was characterized by(transmission-)electron microscopy and synchrotron-based transmission X-ray *** electrochemical corrosion resistance was determined with a standard three-electrode setup and advanced in-situ flow cell measurements.A new electrochemical activity sequence(C15>C36>α-Mg>C14)was obtained,as a result of a stable passive layer formation on theα-solid ***,nm-scale Mg-rich precipitates were identified within the Laves phases,which tend to inhibit the corrosion kinetics.

关键词： Laves phase STEM Magnesium Corrosion Passive layer

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Effect of the Implementation of Emonc in the Reduction of Maternal Deaths in the Department of Collines from 2018 to 2022

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Open Journal of Obstetrics and Gynecology 2024年第2期14卷 259-266页

作者： joachim Aifa Florence Abraham Roger Klikpezo Edgard-Marius Ouendo Badirou Aguemon Faculty of Health Sciences of Cotonou Department of Public Health Cotonou Benin Nursing and Midwifery Training Institute University of Parakou Parakou Benin Assistant in Gynecology-Obstetrics FM-University of Parakou Parakou Benin Full Professor of Public Health and Epidemiology Ouidah Regional Institute of Public Health Ouidah Benin Full Professor of Public Health Faculty of Health Sciences of Cotonou Cotonou Benin

Background: Maternal and neonatal mortality remains a public health problem in Benin. Each year, approximately 1500 maternal deaths and more than 12,000 newborn deaths are recorded there. In order to correct the situation, strategies such as the implementation of Emergency Obstetric and Neonatal Care (EmONC) were initiated. Objective: Determine the rates of maternal deaths in EmONC centers in the Collines department from 2018 to 2022. Framework and Methods: The study took place in Benin precisely in the Collines department. This was a descriptive cross-sectional study. Data collection was carried out during the first two weeks of January 2023 and covered data from the 09 Basic Emergency Obstetric and Neonatal Care centers (BEMONC) and the Obstetric and Neonatal Care centers of Complete Emergency (CEmONC) of the Collines department from 2018 to 2022. An estimate of the ratios of maternal deaths occurring at the level of the EmONC centers of the Collines department from 2018-2022 was carried out followed by constructive suggestions. Results: During the five years (2018 to 2022), the Collines department recorded 42,582 live births with 148 maternal deaths, i.e. a ratio of 348 maternal deaths per 100,000 live births. Between 2018 and 2022, the highest maternal death ratio was recorded in 2019, i.e. 425 maternal deaths per 100,000 live births for all EmONC centers and 607 maternal deaths per 100,000 live births in EmONC centers. The highest maternal death ratio at the BEmONC center level was recorded in 2020, i.e. 129 maternal deaths per 100,000 births. Conclusion: These results suggest that despite the implementation of EmONC in the Collines department, maternal deaths have not decreased. To improve these outcomes for a reduction in maternal deaths, urgent action must be taken.

关键词： Effect BEmONC CEmONC Maternal deaths Department of Collines

In Memory of joachim Messing,a Pioneer in Molecular Genetics and Genomics

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Molecular Plant 2019年第11期12卷 1419-1421页

作者： Students and Postdocs of joachim Messing 机构不祥

We grieve the passing of our beloved and respected mentor,colleague,and friend,***(Jo)Messing,a Distinguished University Professor and director of the Waksman Institute of *** made pioneering contributions that underpin the modern fields of molecular genetics and *** invented the,lshotgunn DNA sequencing method along with a set of toolkits for molecular cloning,which he sent out worldwide for free,advancing the genomic era of *** endeavors guided the directions of both fundamental and applications-based research in agriculture,biofuel,and medicine.

关键词： Pioneer passing directions

Dysfunction of the adhesion G protein-coupled receptor latrophilin 1(ADGRL1/LPHN1)increases the risk of obesity

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Signal Transduction and Targeted Therapy 2024年第5期9卷 2298-2311页

作者： Heba ZabriTorsten Schöneberg AndréNguyen Dietzsch Hadi Al-Hasani joachim Altschmied Katharina Bottermann Jana Brendler Judith Haendeler Susanne Horn Isabell Kaczmarek Antje Körner Kerstin Krause Kathrin Landgraf Diana Le Duc Laura Lehmann Stefan Lehr Stephanie Pick Albert Ricken Rene Schnorr Angela Schulz Martina Strnadová Akhil Velluva Heba Zabri Torsten Schöneberg Doreen Thor Simone Prömel Rudolf Schönheimer Institute of Biochemistry Medical FacultyLeipzig UniversityLeipzigGermany Institute for Clinical Biochemistry and Pathobiochemistry Medical FacultyGerman Diabetes CenterLeibniz Center for Diabetes Research at Heinrich Heine University DüsseldorfDüsseldorfGermany German Center for Diabetes Research(DZD e.V.) Munich-NeuherbergGermany Cardiovascular Degeneration Clinical Chemistry and Laboratory DiagnosticsMedical FacultyUniversity Hospital and Heinrich Heine University DüsseldorfDüsseldorfGermany Cardiovascular Research Institute(CARID) Medical FacultyUniversity Hospital and Heinrich Heine University DüsseldorfDüsseldorfGermany Institute of Pharmacology Medical FacultyUniversity Hospital and Heinrich Heine University DüsseldorfDüsseldorfGermany Institute of Anatomy Medical FacultyLeipzig UniversityLeipzigGermany Center for Pediatric Research Hospital for Children and AdolescentsMedical FacultyLeipzig UniversityLeipzigGermany Helmholtz Institute for Metabolic Obesity and Vascular Research(HI-MAG)of the Helmholtz Zentrum München at the University of Leipzig and University Hospital LeipzigLeipzigGermany Department of Endocrinology NephrologyRheumatologyLeipzig University Medical CenterLeipzigGermany Institute of Human Genetics Leipzig University Medical CenterLeipzigGermany Institute of Cell Biology Department of BiologyHeinrich Heine University DüsseldorfDüsseldorfGermany School of Medicine University of Global Health EquityKigaliRwanda

Obesity is one of the diseases with severe health consequences and rapidly increasing worldwide *** the complex network of food intake and energy balance regulation is an essential prerequisite for pharmacological intervention with obesity.G protein-coupled receptors(GPCRs)are among the main modulators of metabolism and energy ***,for instance,regulate appetite and satiety in certain hypothalamic neurons,as well as glucose and lipid metabolism and hormone secretion from *** in some GPCRs,such as the melanocortin receptor type 4(MC4R),have been associated with early-onset ***,we identified the adhesion GPCR latrophilin 1(ADGRL1/LPHN1)as a member of the regulating network governing food intake and the maintenance of energy *** of the highly conserved receptor in mice results in increased food consumption and severe obesity,accompanied by dysregulation of glucose ***,we identified a partially inactivating mutation in human ADGRL1/LPHN1 in a patient suffering from ***,we propose that LPHN1 dysfunction is a risk factor for obesity development.

关键词： obesity metabolism intake

Impact of renewable energies on the operation and economicsituation of coal fired power stations： Actual situation of coalfired power stations in Germany

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Frontiers in Energy 2017年第2期11卷 119-125页

作者： Hans-joachim KRAUTZ Alexander LISK joachim POSSELT Christian KATZER Department for Power Plant Technology Brandenburg University of Technology Cottbus-Senftenberg 03046 Cottbus Gemany

Due to the fluctuating character of the renewable energy sources the demand of conventional power plants for flexibility is increasing. In the recent years, in Germany there has been a fast rise of production capacity of renewable energies, especially from wind turbines, photovoltaic installations, and biomass plants. The installed nominal power of wind turbines is actually (December 2016) 42 GW and of photovoltaic installations 40?GW. The renewable electric energy production in Germany is about 190?TWh/a, which represents a share of 33% of the yearly demand. The increased need for flexibility affects both the power gradients as well as the minimum load of conventional power plants. Due to this flexibility behaviour, conventional power plants are faced with problems concerning the durability of power plant components, corrosion, more maintenance effort and consequently the overall life expectancy. Another consequence of the increasing share of renewable energies is the decreasing full load operating hours, especially of coal fired and gas power plants. Along with decreasing revenues from the energy exchange market, coal fired power plants are faced with new economically challenges.

关键词： flexible load operation minimal load power gradients power plant maintenance corrosion life expectancy

Combinatorial Dyson-Schwinger equations and inductive data types

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Frontiers of physics 2016年第3期11卷 179-193页

作者： joachim Kock Departament de matemhtiques Universitat Autdnoma de Barcelona Spain

The goal of this contribution is to explain the analogy between combinatorial Dyson-Schwinger equations and inductive data types to a readership of mathematical physicists. The connection relies on an interpretation of combinatorial Dyson-Schwinger equations as fixpoint equations for polynomial functors （established elsewhere by the author, and summarised here）, combined with the now-classical fact that polynomial functors provide semantics for inductive types. The paper is expository, and comprises also a brief introduction to type theory.

关键词： Dyson-Schwinger equations type theory inductive types bialgebras polynomialfunctors

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多重挑战时期的货币政策

中国金融 2024年第4期 32-33页

作者：约阿希姆·内格尔芦国荣(译) 德意志联邦银行中国人民银行甘肃省分行

最重要的挑战仍是过高的通胀率在欧元体系货币政策面临的多重挑战中,最重要的就是欧元区通胀率在过长的时期内持续运行在较高水平,为此,欧洲中央银行通过连续加息、缩减中央银行资产负债表等货币政策措施来稳定价格和预期。

关键词：欧洲中央银行欧元区通胀率货币政策加息中央银行资产负债表多重挑战欧元体系

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Diverged Copies of the Seed Regulatory Opaque-2 Gene by a Segmental Duplication in the Progenitor Genome of Rice, Sorghum, and Maize

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Molecular Plant 2008年第5期1卷 760-769页

作者： Jian-Hong Xu joachim Messing Waksman Institute of Microbiology Rutgers University 190 Frelinghuysen Road Piscataway NJ 08854 USA

Comparative analyses of the sequence of entire genomes have shown that gene duplications, chromosomal segmental duplications, or even whole genome duplications （WGD） have played prominent roles in the evolution of many eukaryotic species. Here, we used the ancient duplication of a well known transcription factor in maize, encoded by the Opaque-2 （O2） locus, to examine the general features of divergences of chromosomal segmental duplications in a lineagespecific manner. We took advantage of contiguous chromosomal sequence information in rice （Oryza sativa, Nipponbare）, sorghum （Sorghum bicolor, Btx623）, and maize （Zea rnays, B73） that were aligned by conserved gene order （synteny）. This analysis showed that the maize 02 locus is contained within a 1.25 million base-pair （Mb） segment on chromosome 7, which was duplicated ≈56 million years ago （mya） before the split of rice and maize 50 mya. The duplicated region on chromosome I is only half the size and contains the maize OHP gene, which does not restore the O2 mutation although it encodes a protein with the same DNA and protein binding properties in endosperm. The segmental duplication is not only found in rice, but also in sorghum, which split from maize 11.9 mya. A detailed analysis of the duplicated regions provided examples for complex rearrangements including deletions, duplications, conversions, inversions, and translocations. Furthermore, the rice and sorghum genomes appeared to be more stable than the maize genome, probably because maize underwent allotetraploidization and then diploidization.

关键词： WGD Opaque-2