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The breaking of flavor democracy in the quark sector

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Chinese Physics C 2017年第9期41卷 38-46页

作者： harald Fritzsch 邢志忠张迪 Physics Department Ludwig Maximilians University Institute of High Energy Physics and School of Physical SciencesUniversity of Chinese Academy of Sciences Center for High Energy Physics Peking University College of Physical Science and Technology Central China Normal University

The democracy of quark flavors is a well-motivated flavor symmetry, but it must be properly broken in order to explain the observed quark mass spectrum and flavor mixing pattern. We reconstruct the texture of flavor democracy breaking and evaluate its strength in a novel way, by assuming a parallelism between the Q=＋2/3 and Q=-1/3 quark sectors and using a nontrivial parametrization of the flavor mixing matrix. Some phenomenological implications of such democratic quark mass matrices, including their variations in the hierarchy basis and their evolution from the electroweak scale to a super-high energy scale, are also discussed.

关键词： flavor democracy quark mass flavor mixing CP violation

Deep digital maintenance

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Advances in Manufacturing 2017年第4期5卷 299-310页

作者： harald Rodseth Per Schjoiberg Andreas Marhaug Department of Mechanical and Industrial Engineering Norwegian University of Science and TechnologyTrondheim Norway

With the emergence of Industry 4.0, mainte-nance is considered to be a specific area of action that is needed to successfully sustain a competitive advantage. For instance, predictive maintenance will be central for asset utilization, service, and after-sales in realizing Industry 4.0. Moreover, artificial intelligence （AI） is also central for Industry 4.0, and offers data-driven methods. The aim of this article is to develop a new maintenance model called deep digital maintenance （DDM）. With the support of theoretical foundations in cyber-physical systems （CPS） and maintenance, a concept for DDM is proposed. In this paper, the planning module of DDM is investigated in more detail with realistic industrial data from earlier case studies. It is expected that this planning module will enable inte- grated planning （IPL） where maintenance and production planning can be more integrated. The result of the testing shows that both the remaining useful life （RUL） and the expected profit loss indicator （PLI） of ignoring the failure can be calculated for the planning module. The article concludes that further research is needed in testing the accuracy of RUL, classifying PLI for different failure modes, and testing of other DDM modules with industrial case studies.

关键词： Maintenance planning Integrated planning(IPL) Digital maintenance Predictive maintenance Industry 4.0

Wireless data transmission using visual codes

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Photonics Research 2014年第5期2卷 150-160页

作者： Thilo Fath Falk Schubert harald Haas Institute for Digital Communications University of EdinburghEH93JL EdinburghUK Innovation Works Germany EADS Deutschland GmbH81663 MunichGermany

In this paper,a new approach for wireless data transmission within an aircraft cabin is *** proposed application enables the transmission of data to a passenger’s user *** wireless in-flight applications are subject to strict frequency and electromagnetic compatibility(EMC)regulations,the data is transferred by optical wireless transmission,specifically by two-dimensional visual *** this end,black-and-white or colored visual code sequences are displayed on the in-flight entertainment *** visual codes are captured by the built-in camera of the passenger’s mobile device and are decoded to reconstruct the transmitted *** order to compensate for frame losses caused by effects like occlusion and motion blur,a temporal forward error correction coding scheme is *** experiments within an Airbus A330 cabin mock-up demonstrate the functionality of the implemented system under realistic conditions such as ambient illumination and geometric *** user devices are used for evaluation;specifically,a low-cost and a high-end smartphone are employed as *** evaluations show that the proposed transmission system achieves data rates of up to 120 kbit/s per individual passenger seat with these user *** the user device has no physical connection to the sensitive on-board system,the proposed transmission system provides an intrinsic safety feature.

关键词： visual illumination correction

Identification of secondary raw materials in mold powders and their melting behavior

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Journal of Iron and Steel Research International 2019年第4期26卷 403-411页

作者： Irmtraud Marschall Nathalie Kolbl harald Harmuth Christina Atzenhofer KI-MET GmbH 8700 LeobenAustria Department Mineral Resources Engineering Chair of CeramicsMontanuniversitaet Leoben8700 LeobenAustria

Commercial mold powders use a limited number of main mineral constituents,but may differ significantly in chemical *** main mineral raw materials of specimens investigated here are quartz,fluorite and free carbon,as well as wollastonite and *** investigations revealed the use of secondary raw materials like blast furnace slag,fly ash,glass scrap and phosphorous slag as further *** the formation of cuspidine was one major point of interest,the influence of the silica source on its formation was identified.A replacement of wollastonite by blast furnace slag reduced the temperature of the first precipitation of cuspidine by about 100℃;the dissociation of sodium carbonate was lowered by-40℃.The lowest temperature of the first Na2CO3 dissociation could be achieved by using fluorine in combination with blast furnace *** formation from the melt is further decreased if sodium and fluorine are both *** use of glass scrap and phosphorous slag strongly reduced the temperature of first melt formation and enhanced cuspidine formation.

关键词： Mold powder Cuspidine Melting Crystallization behavior

Epidemiology of perforating peptic ulcer:A population-based retrospective study over 40 years

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World Journal of Gastroenterology 2020年第35期26卷 5302-5313页

作者： Aydin Dadfar Tom-harald Edna Department of Surgery Levanger HospitalNord-Trøndelag Hospital TrustLevanger 7600Norway Institute of Clinical and Molecular Medicine Norwegian University of Science and TechnologyTrondheim 7491Norway

BACKGROUND The incidence of peptic ulcer disease has decreased during the last few decades,but the incidence of reported peptic ulcer complications has not *** peptic ulcer(PPU)is a severe form of the *** To assess trends in the incidence,presentation,and outcome of PPU over a period of 40 *** This was a single-centre,retrospective,cohort study of all patients admitted to Levanger Hospital,Norway,with PPU from 1978 to *** patients were identified in the Patient Administrative System of the hospital using International Classification of Diseases(ICD),revision 8,ICD-9,and ICD-10 codes for perforated gastric and duodenal *** reviewed the medical records of the patients to retrieve *** statistics were available for all *** incidence of PPU was analysed using Poisson regression with perforated ulcer as the dependent variable,and sex,age,and calendar year from 1978 to 2017 as *** survival analysis was performed to compare long-term survival over the four *** Two hundred and nine patients were evaluated,including 113(54%)***(22%)patients were older than 80 *** age increased from the first to the last decade(from 63 to 72 years).The incidence rate increased with increasing age,but we measured a decline in recent decades for both sexes.A significant increase in the use of acetylsalicylic acid,from 5%(2/38)to 18%(8/45),was observed during the study *** increased significantly over the 40 years of the study,with 22%(10/45)of the patients having an American Society of Anaesthesiologists(ASA)score 4-5 in the last decade,compared to 5%(2/38)in the first ***-nine percent(81/209)of the patients had one or more postoperative *** 100-day mortality and long-term survival were associated with ASA score,without significant variations between the *** Declining incidence rates occurred in recent years,but the patients were olde

关键词： Perforated peptic ulcer American Society of Anaesthesiologists classification Charlson Comorbidity Index Gastric ulcer Duodenal ulcer Epidemiology Incidence Clavien-Dindo classification of complications Mortality

Modelling of dust emissions induced by flow over stockpiles and through packed beds

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Particuology 2021年第6期19卷 55-63页

作者： Daniel Schulz Nadja Schwindt Eberhard Schmidt harald Kruggel-Emden Technische Universitat Berlin Chair of Mechanical Process Engineering and Solids ProcessingEmst-Reuter-Platz 1D-10587 BerlinGermany University of Wuppertal Institute of Particle TechnologyRainer-Gruenter-StrGeb.FFD-42119 WuppertalGermany

Dust emissions during storage of non-moving bulk materials are studied with a numerical *** model relies on a contact-model-free Discrete Element Method(DEM)to model the bulk particle-fluid interaction and the dust removal coupled with Computational Fluid Dynamics(CFD)to model the gas and the dust phase in a multiphase ***,two storage scenarios are considered:a flown through packed bed and a flown over *** the first,the performed simulations reveal that the dust discharge can be correlated with the passing fluid pressure *** the second,a parameter study of factors influencing the dust emissions is *** parameters discussed are the stockpile size,the gas velocity,the slope angle,the particle diameter and the shape of the stockpile,taking into account conical and truncated conical *** release correlations are obtained for both scenarios,which reflect very well the obtained numerical results.

关键词： Computational Fluid Dynamics(CFD) Discrete Element Method(DEM) Dust release correlations Stockpile emissions Packed bed emissions

Four billion years of ophiolites reveal secular trends in oceanic crust formation

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Geoscience Frontiers 2014年第4期5卷 571-603页

作者： harald Furnes Maarten de Wit Yildirim Dilek Department of Earth Science and Centre for Geobiology University of BergenAllegt.415007 BergenNorway AEON and Earth Stewardship Science Research Institute Nelson Mandela Metropolitan University 7701Port Elizabeth 6031South Africa Department of Geology and Environmental Earth Science Miami University State Key Laboratory of Geological Processes and Mineral Resources and School of Earth Science and Mineral ResourcesChina University of Geosciences

We combine a geological, geochemical and tectonic dataset from 118 ophiolite complexes of the major global Phanerozoic orogenic belts with similar datasets of ophiolites from 111 Precambrian greenstone belts to construct an overview of oceanic crust generation over 4 billion years. Geochemical discrimi- nation systematics built on immobile trace elements reveal that the basaltic units of the Phanerozoic ophiolites are dominantly subduction-related （75%）, linked to backarc processes and characterized by a strong MORB component, similar to ophiolites in Precambrian greenstone sequences （85%）. The remaining 25% Phanerozoic subduction-unrelated ophiolites are mainly （74%） of Mid-Ocean-Ridge type （MORB type）, in contrast to the equal proportion of RiftlContinental Margin, Plume, and MORB type ophiolites in the Precambrian greenstone belts. Throughout the Phanerozoic there are large geochemical variations in major and trace elements, but for average element values calculated in 5 bins of 100 million year intervals there are no obvious secular trends. By contrast, basaltic units in the ophiolites of the Precambrian greenstones （calculated in 12 bins of 250 million years intervals）, starting in late Paleo- to early Mesoproterozoic （ca. 2.0-1.8 Ga）, exhibit an apparent decrease in the average values of incom- patible elements such as Ti, P, Zr, Y and Nb, and an increase in the compatible elements Ni and Cr with deeper time to the end of the Archean and into the Hadean. These changes can be attributed to decreasing degrees of partial melting of the upper mantle from HadeanJArchean to Present. The onset of geochemical changes coincide with the timing of detectible changes in the structural architecture of the ophiolites such as greater volumes of gabbro and more common sheeted dyke complexes, and lesser occurrences of ocelli （varioles） in the pillow lavas in ophiolites younger than 2 Ga. The global data from the Precambrian ophiolites, representative of nearly 50% of all known

关键词： Phanerozoic and Precambrian greenstonebeltsOphiolite classificationSubduction-related ophiolitesSubduction-unrelated ophiolitesPrecambrian plate tectonics

ROBUST TRADING RULE SELECTION AND FORECASTING ACCURACY

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Journal of Systems Science & Complexity 2014年第1期27卷 169-180页

作者： SCHMIDBAUER harald ROSCH Angi SEZER Tolga TUNALIOGLU Vehbi Sinan Department of Business Administration Istanbul Bilgi University Santral Campus 34060 Eyiip IstanbulTurkey. FOM University of Applied Scienees Study Centre Munich Arnulfstr. 30 80335 Miinchen Germany. DIME University of Genoa Via Opera Pia 15 16145 Genoa Italy.

Trading rules performing well on a given data set seldom lead to promising out-of-sample results, a problem which is a consequence of the in-sample data snooping bias. Efforts to justify the selection of trading rules by assessing the out-of-sample performance will not really remedy this predica- ment either, because they are prone to be trapped in what is known as the out-of-sample data-snooping bias. Our approach to curb the data-snooping bias consists of constructing a framework for trading rule selection using a-priori robustness strategies, where robustness is gauged on the basis of time- series bootstrap and multi-objective criteria. This approach focuses thus on building robustness into the process of trading rule selection at an early stage, rather than on an ex-post assessment of trading rule fitness. Intra-day FX market data constitute the empirical basis of the proposed investigations. Trading rules are selected from a wide universe created by evolutionary computation tools. The authors show evidence of the benefit of this approach in terms of indirect forecasting accuracy when investing in FX markets.

关键词： A-priori robustness data-snooping bias efficient market hypothesis evolutionary com-putation intra-day FX markets time-series bootstrap trading rule selection.

UNDO, An Aid for Explorative Learning?

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Journal of Computer Science & Technology 1992年第3期7卷 226-236页

作者： harald E. Otto Technical University of Darmstadt D-6100 Darmstadt Germany

New users of an application system, especially computer novices, can become confused and frus- trated after experiencing the first, perhaps not recoverable error situations during the early stages of explora- tion and learning. System facilities, which let users UNDO and REDO executed commands, are suggested to be an aid for active learning and can be used as a method for systematic exploration through recovering from unknown and newly explored (perhaps wrong) system states by cancelling executed commands with UNDO. An explorative learning experiment on a commercial graphics editor with a modified user inter- face revealed reasons, why one-step recall UNDO does not guarantee successful explorative learning of a complex cognitive skill such as graphics editing on computer.

关键词： An Aid for Explorative Learning UNDO