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Skeletal microstructures of cheilostome bryozoans(phylum Bryozoa,class Gymnolaemata):crystallography and secretion patterns

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Marine Life Science & Technology 2024年第3期6卷 405-424页

作者： Christian Grenier Erika Griesshaber wolfgang schmahl Björn Berning Antonio G.Checa Departamento de Estratigrafía y Paleontología Universidad de Granada18071 GranadaSpain Instituto Andaluz de Ciencias de La Tierra CSIC-Universidad de Granada18100 ArmillaSpain Department of Earth and Environmental Sciences Ludwig-Maximilians Universität80333 MunichGermany Institute for Geology University of Hamburg20146 HamburgGermany

Gymnolaemata bryozoans produce CaCO3 skeletons of either calcite,aragonite,or *** extensive research,their crystallography and biomineralization patterns remain *** present a detailed study of the microstructures,min-eralogy,and crystallography of eight extant cheilostome species using scanning electron microscopy,electron backscatter diffraction,atomic force microscopy,and micro-computed *** distinguished five basic microstructures,three calcitic(tabular,irregularly platy,and granular),and two aragonitic(granular-platy and fibrous).The calcitic microstruc-tures consist of crystal aggregates that transition from tabular or irregularly platy to granular *** aragonite consists of fibers arranged into *** all cases,the crystallographic textures are axial,and stronger in aragonite than in calcite,with the c-axis as the fiber *** reconstruct the biomineralization sequence in the different species by considering the distribution and morphology of the growth fronts of crystals and the location of the secretory *** bimineralic species,calcite formation always predates aragonite *** interior compound walls,growth proceeds from the cuticle toward the zooecium *** conclude that,with the exception of tabular calcite,biomineralization is remote and occurs within a relatively wide extrapallial space,which is consistent with the inorganic-like appearance of the *** biomineralization mode is rare among invertebrates.

关键词： Biomineralization Bryozoan Skeleton Calcite Aragonite Electron backscatter diffraction

Identification of greigite in lake sediments and its magnetic significance

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Science China Earth Sciences 2002年第1期45卷 81-87页

作者：胡守云 E.Appel V.Hoffmann W.schmahl 1. Nanjing Institute of Geography & Limnology Chinese Academy of Sciences 210008 Nanjing China 2. Institut für Geologie und Pal?ontologie Universit?t Tübingen 72076 Tübingen Germany 3. Institut für Mineralogie Ruhr-Universtit?t Bochum 44780 Bochum Germany

Detailed rock magnetic investigations and mineralogical analysis were conducted on lacustrine sediments recovered from Zoigê Basin, eastern Tibetan Plateau. Greigite, with fine and homogenous grain size, is found as a main magnetic carrier, which is suspected to be of biochemical origin. In contrast to some reports, greigite within the sediments is not oxidized even after exposure to air for a few years, which could be due to the fact that greigite is sealed by silicate.

关键词： greigite lacustrine sediments rock magnetism X-ray diffraction SEM

New insights into the properties of high-manganese steel

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International Journal of Minerals,Metallurgy and Materials 2021年第5期28卷 782-796页

作者： wolfgang Bleck Steel Institute RWTH Aachen UniversityGermany

In the Collaborative Research Centre 761’s“Steel ab initio-quantum mechanics guided design of new Fe based materials,”scientists and engineers from RWTH Aachen University and the Max Planck Institute for Iron Research conducted research on mechanism-controlled material development with a particular focus on high-manganese alloyed *** 2007 to 2019,a total of 55 partial projects and four transfer projects with industrial participation(some running until 2021)have studied material and process design as well as material *** basic idea of the Collaborative Research Centre was to develop a new methodological approach to the design of structural *** paper focuses on selected results with respect to the mechanical properties of high-manganese steels,their underlying physical phenomena,and the specific characterization and modeling tools used for this new class of *** steels have microstructures that require characterization by the use of modern methods at the *** the process routes,the generation of segregations must be taken into ***,the mechanical properties show a characteristic temperature dependence and peculiarities in their fracture *** mechanical properties and especially bake hardening are affected by short-range ordering *** strain hardening can be adjusted in a never-before-possible range,which makes these steels attractive for demanding sheet-steel applications.

关键词： high-manganese steels stacking fault energy twinning short-range ordering mechanical properties

Cartography and the others-aspects of a complicated relationship

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Geo-Spatial Information Science 2020年第1期23卷 52-60页

作者： wolfgang Kainz Department of Geography and Regional Research University of ViennaWienAustria Collaborative Innovation Center of Geospatial Technology Wuhan UniversityWuhanChina

Cartographic visualizations have been known for thousands of years and have brought forth a wealth of different map projections and cartographic ***,cartography as an independent science has been established only about 100 years ago and sometimes its position among the spatial disciplines is challenged by the scientific *** this respect it is a young science based on a very long tradition of map making,globe production,and the development of map *** and map related visualizations play an important and indispensable role in many other spatial disciplines such as geography and *** has many overlaps with these traditional disciplines as well as with the more recent ones of photogrammetry and remote *** paper reviews fundamental aspects of the conception of space and time throughout human history,the historic development of cartography from a technique of map making to a spatial science,highlighting major milestones in the history of the *** a young science and confronted with major technological developments in the late 20^(th)century cartography underwent several crises as to what exactly is cartography and how it relates to other spatial sciences,in particular to geographic information *** pitfalls and misconceptions are discussed and the three major scientific pillars of cartography are *** relationships of cartography with neighboring disciplines are discussed and the position of cartography vis a vis the others is ***,desirable future developments of scientific cartography are discussed.

关键词： Cartography GIS geodesy photogrammetry remote sensing

How can neuromorphic hardware attain brain-like functional capabilities?

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National Science Review 2024年第5期11卷 11-13页

作者： wolfgang Maass Computer Science and Biomedical Engineering Graz University of Technology

Research on neuromorphic computing is driven by the vision that we can emulate brain-like computing capability, learning capability, and energy-efficiency in novel hardware. Unfortunately, this vision has so far been pursued in a half-hearted manner. Most current neuromorphic hardware (NMHW) employs brain-like spiking neurons instead of standard artificial neurons.

关键词： capabilities attain brain-like functional hardware neuromorphic

Friedrich Ackermann’s scientific research program

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Geo-Spatial Information Science 2023年第2期26卷 141-150页

作者： wolfgang Förstner Department of Photogrammetry UniversityBonnGermany

We sketch Friedrich Ackermann’s research program following the concept of Imre Lakatos,with some historical key developments in the theory and application of aerotriangulation and image *** research program,with its core being statistical estimation theory,has decisively influenced photogrammetry since the 60s,is still fully alive,and a challenge for today’s methods of image *** describe(1)Lakatos’concept of a scientific research program,with its negative and positive heuristics and(2)Ackermann’s research program,clearly made explicit in his PhD,with its mathematical model,the ability to predict theoretical precision and reliability,the potential of analyzing rigorous and approximate method,and the role of *** development of aerotriangulation,later augmented by image matching techniques,is closely connected to Ackermann’s successful attempts to integrate basic research and practical applications.

关键词： Friedrich Ackermann scientific research program aerotriangulation image matching role of theory and application

PREDICTIVE MODELS AND GENERATIVE COMPLEXITY

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Journal of Systems Science & Complexity 2012年第1期25卷 30-45页

作者： wolfgang LHR Max Planck Institute for Mathematics in the Sciences Inselstraβe 22D-04103 LeipziqGermany

The causal states of computational mechanics define the minimal sufficient memory for a given discrete stationary stochastic process. Their entropy is an important complexity measure called statistical complexity （or true measure complexity）. They induce the s-machine, which is a hidden Markov model （HMM） generating the process. But it is not the minimal one, although generative HMMs also have a natural predictive interpretation. This paper gives a mathematical proof of the idea that the s-machine is the minimal HMM with an additional （partial） determinism condition. Minimal internal state entropy of a generative HMM is in analogy to statistical complexity called generative complexity. This paper also shows that generative complexity depends on the process in a nice way. It is, as a function of the process, lower semi-continuous （w.r.t. weak-, topology）, concave, and behaves nice under ergodic decomposition of the process.

关键词： Causal states complexity s-machine generative complexity HMM partially deterministicHMM predictive model statistical.

U-Pb zircon ages for the Luzhenguan Complex in northern part of the eastern Dabie orogen

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Science China Earth Sciences 2005年第9期48卷 1357-1367页

作者： wolfgang Siebe Institut für Geowissenschaften Universit?t Tübingen Tübingen 72074 Germany

The study presents U-Pb zircon ages for granitic gneiss and amphibolite from the Luzhenguan Complex (LZC) in northern part of the eastern Dabie Orogen and their geological significance. Two granitic gneisses and one amphibolite give protolith zircon U-Pb ages of 740 Ma and 725 Ma, respectively. The ages show that the LZC is composed mainly of Neoproterzoic acid and basic igneous rocks, suggesting that there is no Paleozoic active continental marginal rock association in the southern margin of the North China Block in northern part of the eastern Dabie Mountain. Based on the ages and combining the geological and geophysical analyses, the middle-low grade metamorphic rocks in the North Huiyang Belt (NHB) can be divided into three parts, which are the LZC composed mainly of the Neoproterzoic acid and basic igneous rocks, the Neoproterzoic Xianrechong Formation and Xiangyunzhai Formation and the Devonian Zhu- foan Formation and Pangjialing Formation of the Foziling Group, and the suture zone between the Yongtze Block and the North China Block is inferred to be thrust under the NHB.

关键词： Dabie orogen, Luzhenguan Complex, U-Pb zircon age, Neoproterzoic.

Eco-environmental surface modelling requires integration of both extrinsic and intrinsic informations

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Science China Earth Sciences 2021年第1期64卷 185-186页

作者： wolfgang HABER Technical University of Munich WZW FacultyFreising D-85354Germany

Extrinsic information,from satellite observations and the outputs of spatial models,and intrinsic information,from ground observations and spatial sampling,provide two different but complementary streams of information about the Earth’s *** extrinsic and intrinsic informations are indispensable for the modelling of the Earth’s surface systems along with an appropriate method for integrating these two kinds of *** on this idea,the fundamental theorem for Earth’s surface system modeling(FTESM)was proposed,from which several corollaries have been deduced,corresponding to spatial interpolation,spatial upscaling,spatial downscaling,data fusion and model-data assimilation,respectively(Yue et al.,2016).

关键词： surface. intrinsic interpolation