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Designing coal panels in the conditions of associated methane and spontaneous fire hazards

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International Journal of Mining Science and Technology 2020年第4期30卷 525-531页

作者： Stanislaw Prusek Eugeniusz krause Jacek Skiba Central Mining Institute Katowice 40-166Poland

An increase in methane,spontaneous fire and bumping hazards in Polish hard coal mines,observed in the last two decades,led to the need to elaborate the tools allowing proper selection of a range of preventive measures to fight them at the stage of designing coal *** the production of a coal seams in the conditions of associated methane and spontaneous fires hazards in Polish hard coal mines requires elaboration of the design standards for coal panels in gassy coal *** paper presents the guidelines on how to design production in the conditions of associated methane and spontaneous fire *** tools and methodology since the very first research were many times verified by daily mining operations in the conditions of associated methane and spontaneous fire hazards,which confirms their significant contribution to the development of safe and economical mining operations.

关键词： Coal exploitation Methane Spontaneous fires Associated hazards Designing coal panels Ventilation

Frequency-selective Optimization of Periodic Gate Control Signals in DC/DC Converters for EMI-reduction

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Chinese Journal of Electrical Engineering 2022年第4期8卷 11-18页

作者： Caroline krause Stephan Frei On-board Systems Lab TU Dortmund UniversityDortmund 44227Germany

High-frequency switching of power transistors in power electronic systems can cause electromagnetic *** approaches for reducing high-frequency disturbances,such as inserting an additional gate resistor,lead to increased power *** makes achieving both electromagnetic compatibility and power efficiency *** gate drivers help to find a trade-off between these ***,only narrow-band disturbances must be ***,a target signal with a spectrum notched at some frequencies can be *** target signal can be reached by a target-signal-oriented control of the transistor’s *** leads to steeper switching slopes,such that the power losses are less *** arbitrary target signals is *** transistor signal exhibits some physical limitations.A constraint satisfaction problem must be solved,and the gate drive signal must be optimized by applying a residual and Newton’s *** proposed optimization process in the frequency domain is based on the circuit simulation method named“harmonic balance”.Measurements on a DC/DC converter exhibit the benefits of this method.

关键词： Power electronics active gate driving electromagnetic compatibility Newton’s method

Evaluating Local Approximations of the L^(2)-Orthogonal Projection Between Non-Nested Finite Element Spaces

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Numerical Mathematics(Theory,Methods and Applications) 2014年第3期7卷 288-316页

作者： Thomas Dickopf Rolf krause Universit`a della Svizzera italiana(USI University of Lugano)Institute of Computational ScienceVia G.Buffi 136904 LuganoSwitzerland

We present quantitative studies of transfer operators between finite element spaces associated with unrelated *** local approximations of the global L^(2)-orthogonal projection are reviewed and evaluated *** numerical studies in 3D provide the first estimates of the quantitative differences between a range of transfer operators between non-nested finite element *** consider the standard finite element interpolation,Cl´ement’s quasi-interpolation with different local polynomial degrees,the global L^(2)-orthogonal projection,a local L^(2)-quasi-projection via a discrete inner product,and a pseudo-L^(2)-projection defined by a Petrov-Galerkin variational equation with a discontinuous test *** their qualitative and quantitative behaviors in this computational way is interesting per se;it could also be relevant in the context of discretization and solution techniques which make use of different non-nested *** turns out that the pseudo-L^(2)-projection approximates the actual L^(2)-orthogonal projection *** obtained results seem to be largely independent of the underlying computational domain;this is demonstrated by four examples(ball,cylinder,half torus and Stanford Bunny).

关键词： Finite elements unstructured meshes non-nested spaces transfer operators interpolation projection

Product Variability of the ‘Cineole Cassette＇ Monoterpene Synthases of Related Nicotiana Species

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Molecular Plant 2011年第6期4卷 965-984页

作者： Anke Fahnrich Katrin krause Birgit Piechulla University of Rostock Institute for Biological Sciences Albert-Einstein-Str. 3 18059 Rostock Germany

Nicotiana species of the section Alatae characteristically emit the floral scent compounds of the ＇cineole cassette＇ comprising 1,8-cineole, limonene, myrcene, α-pinene, β-pinene, sabinene, and α-terpineol. We successfully isolated genes of Nicotiana alata and Nicotiana langsdorfii that encoded enzymes, which produced the characteristic monoter- penes of this ＇cineole cassette＇ with α-terpineol being most abundant in the volatile spectra. The amino acid sequences of both terpineol synthases were 99% identical. The enzymes cluster in a monophyletic branch together with the closely related cineole synthase of Nicotiana suaveolens and monoterpene synthase 1 of Solanum lycopersicum. The cyclization reactions （α-terpineol to 1,8-cineole） of the terpineol synthases of N. alata and N. langsdorfii were less efficient compared to the ＇cineole cassette＇ monoterpene synthases of Arabidopsis thaliana, N. suaveolens, Salvia fruticosa, Salvia officinalis, and Citrus unshiu. The terpineol synthases of IV. alata and N. langsdorfii were localized in pistils and in the adaxial and abaxial epidermis of the petals. The enzyme activities reached their maxima at the second day after anthesis when flowers were fully opened and the enzyme activity in N. alata was highest at the transition from day to night （diurnal rhythm）.

关键词： Nicotiana alata Nicotiana langsdorfii cineole cassette terpineol synthase multiproduct enzyme monoterpene synthase 1,8-cineole, α-terpineol.

Effect of HTS Superconductors on Homogeneity of Measurement Field in Low Field Nuclear Magnetic Resonance Detection

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Chinese Physics Letters 2010年第8期27卷 250-252页

作者：董慧张懿 krause Hans-Joachim 谢晓明 State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 Institute of Bio- and Nanosystems Forschungszentrum Jiilich. D-52425 Jiilieh Germany Graduate University of the Chinese Academy of Sciences Beijing 100049

In recent years, superconducting quantum interference devices （SQUIDs） have been demonstrated to be useful in the low field nuclear magnetic resonance （NMR） measurements. The high temperature superconducting （HTS） SQUID used in our experiments has a frequency-independent sensitivity of 40-50fT/Hz^1/2. When a liquid nitrogen cooled LC circuit is employed to form a tuned circuit with the SQUID, the sensitivity of the system can be further enhanced. The LC circuit consists of a capacitor and a coil made of copper wire or HTS tape, which is inductively coupled to the SQUID. However, the homogeneity of the measurement field deteriorates because of the HTS tape coil in the proximity of the sample. In contrast, the thin film SQUID with a washer area of 1 cm^2 has no effect on the NMR signal. Therefore, the impairment of the measurement field homogeneity in the case of different superconducting elements nearby is discussed by examining the free induction decay signals at 9 kHz. It is found that a square superconducting film with an area of i cm^2 may compensate for the inhomogeneity of the measurement field after the adjustment of its position.

关键词： HIGH temperature superconductors NUCLEAR magnetic resonance SUPERCONDUCTING quantum interference devices PHYSICS experiments LIQUID nitrogen SENSITIVITY analysis

Resistance to anti-tubulin agents:From vinca alkaloids to epothilones

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Cancer Drug Resistance 2019年第1期2卷 82-106页

作者： Werner krause Formerly Bayer AG Project ManagementBerlin 13353Germany

This review describes the mechanism of action-inhibition of microtubules-and the most important mechanisms of resistance for vinca alkaloids,taxanes and *** is a major problem in vinca and taxane chemotherapy and arises in most cases from overexpression of efflux pumps that transport the drugs out of the cancer cells and from modifications of the target,the microtubules,by overexpression of tubulin isotypes or by attachment of proteins to the ends of the microtubules so that the target is no longer recognized by the *** some cases,however,this process can have the opposite effect,leading to sensitization,e.g.,for vinca alkaloids in cases where taxanes are not or no longer *** link between resistance due to efflux pumps and the pharmacokinetics and metabolism of the drugs is also *** types of resistance that are addressed include detoxification of drugs within the cancer cell and blockade of apoptosis,post-translational modifications of microtubules and other protein pathways,micro-RNAs,induction of oncogenes,and cancer stem cells,which,taken together,offer particularly multifold possibilities for preventing drug *** use of biomarkers for the prediction of clinical outcome and for the direction of future therapy is also addressed.

关键词： Microtubules tumor heterogeneity mechanisms of resistance cancer stem cells biomarkers pharmacokinetics metabolism

Basin-wide hydrological system assessment under climate change scenarios through conceptual modelling

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International Journal of Digital Earth 2020年第8期13卷 915-938页

作者： Cenk Donmez Suha Berberoglu Ahmet Cilek Peter krause Division of Remote Sensing and GIS Department of Landscape ArchitectureFaculty of ArchitectureUniversity of CukurovaAdanaTurkey Thuringian State Institute for Environment and Geology JenaGermany

Mediterranean region is identified as a primary hot-spot for climate change due to the expected temperature and rainfall *** the potential impacts of climate change on the hydrology in these regions is an important task to develop long-term water management *** aim of this study was to quantify the potential impacts of the climate changes on local hydrological quantities at the Goksu Watershed at the Eastern Mediterranean,Turkey as a case study.A set of Representative Concentration Pathways(RCP)scenarios were used as drivers for the conceptual hydrological model J2000 to investigate how the hydrological system and the underlying processes would respond to projected future climate *** model was implemented to simulate daily hydrological quantities including runoff generation,Actual Evapotranspiration(AET)and soil-water balance for present(2005–2015)and future(up to 2100).The results indicated an increase of both precipitation and runoff throughout the region from January to *** region showed a strong seasonally dependent runoff regime with higher flows during winter and spring and lower flows in summer and *** study provides a comparative methodology to include meteorological-hydrological modelling integration that can be feasible to assess the climate change impacts in mountainous regions.

关键词： Hydrological modelling RCP climate change Mediterranean watershed

Phosphine functionalised multiwalled carbon nanotubes:A new adsorbent for the removal of nickel from aqueous solution

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Journal of Environmental Sciences 2012年第6期24卷 1133-1141页

作者： Muleja Anga Adolph Yangkou Mbianda Xavier Pillay Kriveshini krause Rui Department of Chemical Technology University of JohannesburgDoornfontein Campus P.O Box 17011JohannesburgSouth Africa

Synthesised triphenylphosphine-linked multiwalled carbon nanotubes （Tpp-MWCNTs） were used to study the adsorption of nickel in aqueous solutions and their adsorption capabilities were compared with purified *** adsorption capacity increased with an increase in pH for all *** adsorption equilibrium was reached in 40 and 30 min for purified MWCNTs and Tpp-MWCNTs,*** Freundlich and Langmuir isotherms used to investigate the adsorption process fitted the experimental data well with the correlation coefficient R 2 close to 1 for all *** the other hand,the experimental data fitted well with a pseudo secondorder *** speciation of nickel also influenced the adsorption on the purified and *** adsorbents used in this study showed superior adsorption capacity when compared to other adsorbents reported in the literature.

关键词： phosphine functionalised multiwalled carbon nanotubes adsorbent XPS remediation nickel

Market Structure and Information in Payment Card Markets

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International Journal of Automation and computing 2011年第3期8卷 364-370页

作者： Biliana Alexandrova-Kabadjova Edward Tsang Andreas krause General Directorate of Payment Systems and Risk Banco de Mexico C.P. 06059 Mexico Centre for Computational Finance and Economic Agents University of EssexColchester CO4 3SQ UK School of Management University of BathBath BA2 7AY UK

This paper investigates the structure of the payment card market, with consumers and merchants basing their subscription decisions on different information sets. We find that the market structure depends crucially on the information set on which consumers and merchants base their subscription decisions. In the studied case, we observe that a market with few cards dominating only emerges when decisions are based on very limited information. Under the same conditions using a complete information set, all cards survive in the long run. The use of an agent-based model, focusing on the interactions between merchants and consumers, as a basis for subscription decisions allows us to investigate the dynamics of the market and the effect of the indirect network externalities rather than investigating only equilibrium outcomes.

关键词： Two-sided markets network externalities agent-based modelling competition payment cards.