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Journal of Computational Mathematics 2009年第2期27卷 360-387页

作者： Reinhold Schneider Thorsten Rohwedder Alexey Neelov johannes Blauert Institute for Mathematics Technical University BerlinStraβe des 17.Juni 13510623 BerlinGermany Institute of Physics University of BaselKlingelbergstrasse 824056 BaselSwitzerland Institute for Mathematics Technical University BerlinStraβe des 17. Juni 13510623 BerlinGermany

In this article, we analyse three related preconditioned steepest descent algorithms, which are partially popular in Hartree-Fock and Kohn-Sham theory as well as invariant subspace computations, from the viewpoint of minimization of the corresponding functionals, constrained by orthogonality conditions. We exploit the geometry of the admissible manifold, i.e., the invariance with respect to unitary transformations, to reformulate the problem on the Grassmann manifold as the admissible set. We then prove asymptotical linear convergence of the algorithms under the condition that the Hessian of the corresponding Lagrangian is elliptic on the tangent space of the Grassmann manifold at the minimizer.

关键词： Eigenvalue computation Grassmann manifolds Optimization Orthogonalityconstraints Hartree-Fock theory Density functional theory PINVIT

New approaches to water purification for resource- constrained settings： Production of activated biochar by chemical activation with diammonium hydrogenphosphate

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 194-208页

作者： Mohit Nahata Chang Y. Seo Pradeep Krishnakumar johannes Schwank Department of Chemical Engineering University of Michigan-Ann Arbor Ann Arbor MI 48109 USA

A significant portion of the world＇s population does not have access to safe drinking water. This problem is most acute in remote, resource-constrained rural settings in developing countries. Water filtration using activated carbon is one of the important steps in treating con- taminated water. Lignocellulosic biomass is generally available in abundance in such locations, such as the African rain forests. Our work is focused on developing a simple method to synthesize activated biochar from locally available materials. The preparation of activated biochar with diammonium hydrogenphosphate （DAP） as the activating agent is explored under N2 flow and air. The study, carried out with cellulose as a model biomass, provides some insight into the interaction between DAP and biomass, as well as the char forming mechanism. Various characterization techniques such as N2 physisorption, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy and Raman spectroscopy are utilized to compare the properties between biochar formed under nitrogen and partial oxidative conditions. At a temperature of 450 ℃, the loading of DAP over cellulose is systematically varied, and its effect on activation is examined. The activated biochar samples are predominantly microporous in the range of concentrations studied. The interaction of DAP with cellulose is investigated and the nature of bonding of the heteroatoms to the carbonaceous matrix is elucidated. The results indicate that the quality of biochar prepared under partial oxidation condition is comparable to that ofbiochar prepared under nitrogen, leading to the possibility of an activated biochar production scheme on a small scale in resource-constrained settings.

关键词： cellulose DAP activation heteroatom,microporous

The Product of the Restrained Domination Numbers of a Graph and Its Complement

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Acta Mathematica Sinica,English Series 2014年第3期30卷 445-452页

作者： johannes H.HATTINGH Ernst J.JOUBERT Department of Mathematics East Carolina University Department of Mathematics University of Johannesburg

Let G=（V,E） be a graph.A set S■V is a restrained dominating set if every vertex in V-S is adjacent to a vertex in S and to a vertex in *** restrained domination number of G,denoted γr（G）,is the smallest cardinality of a restrained dominating set of *** this paper,we show that if G is a graph of order n≥4,then γr（G）γr（G）≤*** also characterize the graphs achieving the upper bound.

关键词： Graph domination restrained domination Nordhaus-Gaddum upper bound

Diversity of wing patterns and abdomen-generated substrate sounds in 3 European scorpionfly species

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Insect Science 2015年第4期22卷 521-531页

作者： Manfred Hartbauer johannes Gepp Karin Hinteregger Stephan Koblmuller Institute of Zoology KarI-Franzens-University Graz Universitatsplatz 2 8010 Graz Institute for Nature Conservation Herdergasse 3 8010 Graz Austria

In the genus Panorpa （Insecta： Mecoptera）, also known as scorpionflies, pre- mating behavior includes repeated sequences of slow wing movements （waving, fanning, flagging） which are accompanied by rapid abdomen vibrations that generate substantial substrate-borne sound. It is still unknown whether wing patterns or vibratory signals contain information about species identity, sex and/or the quality of potential mating part- ners. Besides species-specific pheromones, these multimodal signals may be of particular importance for the maintenance of reproductive isolation in sympatrically occurring scor- pionfly species. Here, we analyzed phyologenetic relationships among, and the pattern of forewings as well as substrate-borne sound in 3 different sympatric Central-European scorpionfly species （P communis, P germanica, and P alpina）. Divergence time estimates, based on 879 bp of the mitochondrial COI gene, indicate longstanding separate evolu- tionary histories for the studied Panorpa species. Morphological analysis revealed that wing length as an indicator of body size increased in the following order： P alpina 〈 P. germanica 〈 P. communis. Individuals can be assigned to the correct species and sex with high accuracy just by evaluation of the number of dark spots and the proportion of wing pigmentation. Despite high variability of interpulse period at an individual level, across species analysis revealed a positive correlation of average interpulse period as well as mean signal amplitude with forewing length. These results suggest wing patterns, but less likely vibratory signals, to contain information about species identity. Furthermore, receivers may be able to estimate the body size of a signaler solely on the basis of substrate-borne sound.

关键词： courtship signals laser vibrometry phylogeny species recognition substrate-borne sound wing pattern

Resistance to chemoimmunotherapy in non-small-cell lung cancer

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Cancer Drug Resistance 2020年第3期3卷 445-453页

作者： Maximilian johannes Hochmair Respiratory Oncology Unit Vienna North Hospital-Klinik FloridsdorfVienna 1210Austria.

Recent clinical trials evaluating the combination of chemotherapy with immune checkpoint inhibition for the primary treatment of lung cancer showed increased progression-free and overall survival compared with chemotherapy ***,the combination of these two modalities is less than additive and the mechanisms of resistance to this therapeutic intervention are discussed *** far,the conventional biomarkers for immunotherapy,namely programmed death-ligand 1 expression or tumor mutational burden are poor predictors of the efficacy of immunochemotherapy,and the optimal sequence of chemotherapy and immunotherapy has yet to be defined.

关键词： Lung cancer chemotherapy immunotherapy combination pembrolizumab resistance

Routing through open spaces-A performance comparison of algorithms

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Geo-Spatial Information Science 2018年第3期21卷 247-256页

作者： Stefan Hahmann Jakob Miksch Bernd Resch johannes Lauer Alexander Zipf GIScience Research Group Institute of GeographyHeidelberg UniversityHeidelbergGermany Fraunhofer IVI Fraunhofer Institute for Transportation and Infrastructure SystemsDresdenGermany Department of Geoinformatics-Z_GIS University of SalzburgAustria Center for Geographic Analysis Harvard UniversityCambridgeMAUSA HERE GmbH&Co KG Schwalbach am TaunusGermany

Finding the shortest path through open spaces is a well-known challenge for pedestrian routing engines.A common solution is routing on the open space boundary,which causes in most cases an unnecessarily long route.A possible alternative is to create a subgraph within the open *** paper assesses this approach and investigates its implications for routing engines.A number of algorithms(Grid,Spider-Grid,Visibility,Delaunay,Voronoi,Skeleton)have been evaluated by four different criteria:(i)Number of additional created graph edges,(ii)additional graph creation time,(iii)route computation time,(iv)routing *** show that each algorithm has advantages and disadvantages depending on the use *** identify the algorithms Visibility with a reduced number of edges in the subgraph and Spider-Grid with a large grid size to be a good compromise in many scenarios.

关键词： OpenStreetMap routing open space navigation pedestrian polygon

Editorial for special issue on hydrogen metallurgy

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International Journal of Minerals,Metallurgy and Materials 2022年第10期29卷 1817-1819页

作者： Jianliang Zhang johannes Schenk Zhengjian Liu Kejiang Li School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Department of Metallurgy Chair of Ferrous MetallurgyMontanuniversität LeobenFranz-Josef Straße 188700 LeobenAustria

*** The carbon neutral strategy is promoting the transformation and upgrading of the traditional metallurgical industry,and the high-quality and low-carbon reform of the metallurgical industry is ***,as a clean energy... 详细信息

关键词： upgrading metallurgy industry

Hepatitis C-committing the world to an eradication of the infection

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Hepatobiliary Surgery and Nutrition 2021年第1期10卷 96-99页

作者： johannes Wiegand Thomas Berg Klinik für Onkologie GastroenterologieHepatologiePneumologie und InfektiologieBereich HepatologieLeipzigGermany

In a current issue of The Lancet,Spearman and colleagues have provided an extensive global review on hepatitis C virus(HCV)infection,which covers important aspects of epidemiology,natural history,key populations at ri... 详细信息

关键词： infection epidemiology linkage

Eccentric error and compensation in rotationally symmetric laser triangulation

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仪器仪表学报 2007年第9期28卷 1548-1553页

作者： Wang Lei Gao Jun Wang Xiaojia johannes Eckstein Peter Ott Lab of Image Information Processing School of Computer and Information Hefei University of Technology Hefei 230009 China Optical Engineering Lab. Heilbronn University Heilbronn D-74081 Germany Dep. of Mechanical and Electrical Engineering Xiamen University Xiamen 361005 China

Rotationally symmetric triangulation(RST)sensor has more flexibility and less uncertainty limits because of the abaxial rotationally symmetric optical *** if the incident laser is eccentric,the symmetry of the image will descend,and it will result in the eccentric error especially when some part of the imaged ring is *** model of rotationally symmetric triangulation that meets the Schimpflug condition is presented in this *** error from eccentric incident laser is *** is pointed out that the eccentric error is composed of two parts,one is a cosine in circumference and proportional to the eccentric departure factor,and the other is a much smaller quadric factor of the *** the ring is complete,the first error factor is zero because it is integrated in whole ring, but if some part of the ring is blocked,the first factor will be the main *** verifies the result of the a- *** last,a compensation method to the error when some part of the ring is lost is presented based on neural *** results of experiment show that the compensation will make the absolute maximum error descend to half,and the standard deviation of error descends to 1/3.

关键词：补偿作用旋转对称激光三角测量法偏心因子视力测量神经网络

Self-templated covalent functionalization of graphitic surfaces with a quasi-periodic pattern

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Aggregate 2022年第4期3卷 121-130页

作者： Yuanzhi Xia johannes Seibel Steven De Feyter Division of Molecular Imaging and Photonics Department of ChemistryKU LeuvenLeuvenBelgium

Patterned covalent functionalization of graphitic surfaces(GSs)is of interest in the development of devices and nanocomposite *** contrast to the strategies using external templates or control for realizing patterned covalent functionalization of GSs,here,we present a self-templated strategy by exploiting the synergistic effects of chemical and physical functionalization of ***,a diazonium salt is reduced by potassium iodide(KI)in dimethyl sulfoxide while the solution is in contact with a GS,resulting in its spatially heterogeneous,that is,chemical and physical,*** heterogeneous functionalization leads to a quasiperiodic pattern of striped corrals with three equivalent orientations in the covalent *** formation of the striped corrals is ascribed to physisorbed domains formed by self-assembled N_(2),which is produced in situ during the reduction of the diazonium salt,preventing the covalent functionalization.

关键词： diazonium chemistry graphitic surfaces patterned covalent functionalization quasi-periodic patterning self-templated strategy