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Online Induction of Probabilistic Real-Time Automata

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Journal of Computer Science & Technology 2014年第3期29卷 345-360页

作者： Jana schmidt Stefan Kramer Technische Universitt Mnchen Institut fr Informatik/I12Boltzmannstr. 385748 Garching b. MnchenGermany Johannes Gutenberg-Universitt Mainz Institute for Computer ScienceStaudingerweg 955128 MainzGermany

The probabilistic real-time automaton （PRTA） is a representation of dynamic processes arising in the sciences and industry. Currently, the induction of automata is divided into two steps： the creation of the prefix tree acceptor （PTA） and the merge procedure based on clustering of the states. These two steps can be very time intensive when a PRTA is to be induced for massive or even unbounded datasets. The latter one can be efficiently processed, as there exist scalable online clustering algorithms. However, the creation of the PTA still can be very time consuming. To overcome this problem, we propose a genuine online PRTA induction approach that incorporates new instances by first collapsing them and then using a maximum frequent pattern based clustering. The approach is tested against a predefined synthetic automaton and real world datasets, for which the approach is scalable and stable. Moreover, we present a broad evaluation on a real world disease group dataset that shows the applicability of such a model to the analysis of medical processes.

关键词： probabilistic real-time automata online induction maximum frequent pattern based clustering

An Efficient Calculation of Photonic Crystal Band Structures Using Taylor Expansions

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Communications in Computational Physics 2014年第10期16卷 1355-1388页

作者： Dirk Klindworth Kersten schmidt Research Center MATHEON TU BerlinDepartment of MathematicsStraße des 17.Juni 13610623 BerlinGermany.

In this paper we present an efficient algorithm for the calculation of photonic crystal band structures and band structures of photonic crystal *** method relies on the fact that the dispersion curves of the band structure are smooth functions of the quasi-momentum in the one-dimensional Brillouin *** show the derivation and computation of the group velocity,the group velocity dispersion,and any higher derivative of the dispersion *** derivatives are then employed in a Taylor expansion of the dispersion *** control the error of the Taylor expansion with the help of a residual estimate and introduce an adaptive scheme for the selection of nodes in the one-dimensional Brillouin zone at which we solve the underlying eigenvalue problem and compute the derivatives of the dispersion *** proposed algorithm is not only advantageous as it decreases the computational effort to compute the band structure but also because it allows for the identification of crossings and anti-crossings of dispersion curves,*** identification is not possible with the standard approach of solving the underlying eigenvalue problem at a discrete set of values of the quasi-momentum without taking the mode parity into account.

关键词： Photonic crystals band structure calculation group velocity Taylor expansion adaptivity

Scientific guidelines for preclinical research on potentised preparations manufactured according to current pharmacopoeias—the PrePoP guidelines

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Journal of Integrative Medicine 2024年第5期 533-544页

作者： Alexander L.Tournier Leoni V.Bonamin Susann Buchheim-schmidt Steven Cartwright Christoph Dombrowsky Paul Doesburg Carla Holandino Maria Olga Kokornaczyk Everine B.van de Kraats Jesús Antonio López-Carvallo Papiya Nandy JoséManuel Mazón-Suástegui Fateme Mirzajani Bernard Poitevin Claudia Scherr Karin Thieves Sandra Würtenberger Stephan Baumgartner Institute of Complementary and Integrative Medicine University of Bern Institute of Integrative Medicine Witten/Herdecke University Homeopathy Research Institute Graduate Program on Environmental and Experimental Pathology Paulista University Department of Medical Science Deutsche Hom?opathie-Union DHU-Arzneimittel GmbH&Co.KG Cherwell Laboratory for Fundamental Research in Homeopathy Society for Cancer Research Hiscia Research Institute Laboratório Multidisciplinar de Ciências Farmacêuticas Universidade Federal do Rio de Janeiro World Water Community Departamento de Acuicultura Facultad de Ciencias del MarUniversidad Católica del Norte Centre for Interdisciplinary Research and Education Laboratorio de Homeopatía Acuícola y Semillas Marinas Centro de Investigaciones Biológicas del Noroeste Protein Research Center Shahid Beheshti University Department of Medical Laboratory Science College of ScienceKnowledge University Socie′te′Savante d’Hom′eopathie Sola Salus Institute for Homeopathic Research Scientific Society for Homeopathy

Objective: Pharmacopoeias regulate the manufacture of potentised pharmaceutical preparations used in different branches of complementary and integrative medicine. The physicochemical properties and biological activity of these preparations are often investigated in preclinical research, yet no guidelines for experimental research currently exist in this area. The present PrePoP guidelines aim to provide recommendations to promote high-quality, statistically sound, and reproducible preclinical research on potentised ***: Input was gathered from researchers nominated by the relevant scientific societies using a simplified Delphi consensus approach covering the most relevant aspects of basic research methodology in the field including appropriate controls, sample preparation and handling, and statistics. After three rounds of feedback, a consensus was finally reached on the most important aspects and considerations for conducting high-quality research on potentised ***: We present a series of recommendations on a range of topics including experimental controls,system stability, blinding and randomisation, environmental influences, and procedures for the preparation of potentised samples and controls, and we address some specific challenges of this research ***: This expert consensus process resulted in a robust set of methodological guidelines for research on potentised preparations and provides a valuable framework that will inform and improve the quality of subsequent research in this emerging field.

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Extraintestinal heterotopic gastric tissue simulating acute appendicitis

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World Journal of Gastroenterology 2008年第14期14卷 2268-2269页

作者： Elizabeth Bender Steven P schmidt Department of Surgery and Division of Surgical Research Summa Health System Akron Ohio 44304 United States

We describe the case of a 68-year-old otherwise healthy male who presented to our emergency room with signs and symptoms of acute appendicitis. Exploratory surgery revealed a normal appendix. Further examination revealed an enlarged lymph node-like mass of tissue near the appendix, in the ileocecal mesentery. This mass was removed and was found to be inflamed heterotopic gastric tissue. Although reports of heterotopic gastric tissue in the literature are common, we believe that this case represents the first report of inflamed heterotopic gastric tissue simulating appendicitis.

关键词： Heterotopic gastric mucosa Acute appendicitis

Molecular level simulations on multi-component systems --a morphology prediction method

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Frontiers of Chemical Science and Engineering 2013年第1期7卷 49-54页

作者： C. schmidt J. ULRICH Center for Engineering Science Thermal Process Engineering Martin Luther University Halle-Wittenberg D-06099 Halle (Saale) Germany

The crystal morphology grown from a solution composed of an organic solvent, solute and additive can be predicted reliably by a computational method. Modeling the supersaturated solution as liquid phase is achieved by employing commercial software. The molecular composition of this solution is a required input parameter. The face specific diffusion coefficient of the solid （crystal surface） and liquid （solution） system is determined using the molecular dynamics procedure. The obtained diffusion coefficient is related to the specific face growth rate via the attachment energy of the pure morphology. The significant improvements are achieved in the morphology prediction because the investigation on the face growth rates in a complex growth environment （as multi-component solutions with additives） can be carried out based on the diffusion coefficients.

关键词： crystallization morphology molecular dynamics solution

Three-dimensional mode coupling around a seamount

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Science China(Physics,Mechanics & Astronomy) 2011年第9期54卷 1561-1569页

作者： LUO WenYu ZHANG RenHe schmidt Henrik State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 China Department of Mechanical Engineering Massachusetts Institute of Technology Massachusetts 02139 USA

A recently developed three-dimensional normal-mode model is adopted to investigate mode coupling around a seamount in a deep water environment. As indicated by the theoretical analysis and verified by the numerical results, strong mode coupling occurs at the edge of a seamount under certain conditions. Therefore, mode coupling is critical for the investigation of the acoustic field in the presence of a seamount. In addition, the issue regarding the number of sectors assuring convergence is also presented. This issue is important in a two-way coupled-mode approach, especially for solving three-dimensional problems, because the computational effort increases dramatically with the number of sectors in representing a varying bathymetry. The theoretical analysis as well as the numerical example in this paper shows that artificial diffraction lobes form in the event that uniform discretization is used with a horizontal step size greater than half of the acoustic wavelength. However, by using random discretization instead, such artificial diffraction lobes are diffused, resulting in a faster convergence rate.

关键词： normal mode three-dimensional mode coupling seamount

Diatom assemblages and quantitative reconstruction for paleosalinity from a sediment core of Chencuo Lake,southern Tibet

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Science China Earth Sciences 2004年第6期47卷 522-528页

作者： C. Kamenik R.schmidt Institute of Limnology Austrian Academy of Sciences A-5310 Mondsee AustriaInstitute of Limnology Austrian Academy of Sciences A-5310 Mondsee Austria

Combining with the diatom-based conductivity transfer function from Qing-hai-Xizang (Tibetan) Plateau lakes, the lake salinity for the past 300 years was quantitatively reconstructed based on the analysis of diatom assemblages from a sediment core in Chencuo Lake, southern Tibet. The distinct negative relationship between inferred conductivity and recorded lakelevels in recent years suggests that the lake salinity can reflect the fluctuations of effective moisture of climate in lake area. The salinity inferred from diatoms reveals several major hydrological episodes. An obvious desalination of lake water occurred during the last cold interval of the Little Ice Age (about 1845–1885 AD), indicating a cold and moist climate. The lake salinity presented a rapid increase trend since the middle 1960s, with a peak value and high amplitude of salinity variability in the whole past 300 years. The low effective moisture inferred from the lake salinity may have contributed to the enhanced evaporation by the continuous increase of temperature in recent years. Keywords diatoms - conductivity or salinity - quantitative reconstruction - Chencuo Lake

关键词： diatoms, conductivity or salinity, quantitative reconstruction, Chencuo Lake.

Longitudinal height-diameter curves for Norway spruce, Scots pine and silver birch in Norway based on shape constraint additive regression models

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Forest Ecosystems 2018年第2期5卷 109-125页

作者： Matthias schmidt Johannes Breidenbach Rasmus Astrup Northwest German Forest Research Institute Forest Growth Gratzelstr 2 37079 Gottingen Germany Norwegian Institute for Bioeconomy Research National Forest Inventory Postboks 115 1431 As Norway

Background： Generalized height-diameter curves based on a re-parameterized version of the Korf function for Norway spruce （Piceo abies （L.） Karst.）, Scots pine （Pinus sylvestris L.） and silver birch （Betula pendula Roth） in Norwa are presented. The Norwegian National Forest Inventory （NFI） is used as data base for estimating the model parameters. The derived models are developed to enable spatially explicit and site sensitive tree height imputatio in forest inventories as well as future tree height predictions in growth and yield scenario simulations. Methods： Generalized additive mixed models （gamm） are employed to detect and quantify potentially non-linear effects of predictor variables. In doing so the quadratic mean diameter serves as longitudinal covariate since stand ag as measured in the NFI, shows only a weak correlation with a stands developmental status in Norwegian forests. Additionally the models can be locally calibrated by predicting random effects if measured height-diameter pairs are available. Based on the model selection of non-constraint models, shape constraint additive models （scare） were fit tc incorporate expert knowledge and intrinsic relationships by enforcing certain effect patterns like monotonicity. Results： Model comparisons demonstrate that the shape constraints lead to only marginal differences in statistical characteristics but ensure reasonable model predictions. Under constant constraints the developed models predict increasing tree heights with decreasing altitude, increasing soil depth and increasing competition pressure of a tree. / two-dimensional spatially structured effect of UTM-coordinates accounts for the potential effects of large scale spatial correlated covariates, which were not at our disposal. The main result of modelling the spatially structured effect is lower tree height prediction for coastal sites and with increasing latitude. The quadratic mean diameter affects both the level and the slope of the height-diameter

关键词： Height-diameter curve Norway spruce Scots pine Silver birch Norwegian national forest inventory Shape constrained additive models

Modelling the population fluctuation of winter moth and mottled umber moth in central and northern Germany

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Forest Ecosystems 2019年第1期6卷 38-55页

作者： Anika Hittenbeck Ronald Bialozyt Matthias schmidt Northwest German Forest Research Institute

Background: Winter moth(Operophtera brumata) and mottled umber moth(Erannis defoliaria) are forest Lepidoptera species characterized by periodic high abundance in a 7–11 year cycle. During outbreak years they cause severe defoliation in many forest stands in Europe. In order to better understand the spatio-temporal dynamics and elucidate possible influences of weather, stand and site conditions, a generalized additive mixed model was developed. The investigated data base was derived from glue band catch monitoring stands of both species in Central and North Germany. From the glue bands only female moth individuals are counted and a hazard code is calculated. The model can be employed to predict the exceedance of a warning threshold of this hazard code which indicates a potential severe defoliation of oak stands by winter moth and mottled umber in the coming ***: The developed model accounts for specific temporal structured effects for three large ecoregions and random effects at stand level. During variable selection the negative model effect of pest control and the positive model effects of mean daily minimum temperature in adult stage and precipitation in early pupal stage were ***: The developed model can be used for short-term predictions of potential defoliation risk in Central and North Germany. These predictions are sensitive to weather conditions and the population dynamics. However, a future extension of the data base comprising further outbreak years would allow for deeper investigation of the temporal and regional patterns of the cyclic dynamics and their causal influences on abundance of winter moth and mottled umber.

关键词： Operophtera brumata Erannis defoliaria Generalized additive mixed model Weather effect Insect pest outbreaks