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制造技术与机床 2003年第4期 117-119页

作者： jochen kress 沈捷德国

密烘铸铁(CGI)是一种耐高温和大机械载荷的材料，这就是为什么它在现代汽车工业中应用日益增多的原因。可是CGI不能用传统方法经济地加工，只能用有几个刀刃的刀具进行微切削才能保证成功加工。

关键词：密烘铸铁汽车刀具微切削经济法机械加工

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密烘铸铁(CGI)的经济加工

世界制造技术与装备市场 2003年第2期 170-172页

作者： jochen kress 沈捷

密烘铸铁(CGI)是一种耐高温和大机械载荷的材料,这就是为什么它在现代汽车工业中应用日益增多的原因。可是,CGI不能用传统方法经济地加工,只能用有几个刀刃的刀具进行微切削才能保证成功加工。

关键词：密烘铸铁 CGI 微切削机械加工经济性汽车

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如何提升切削生产能源效率

现代制造 2014年第2期 26-29页

作者： ECKEHARD KALHFER jochen kress 阿伦应用技术大学 Mapal Dr.kress KG公司董事会

能源成本不断走高,通过分析切削设备刀具能源消耗与切削工序,可确定能效提升的具体方法;同时,优化刀具和切削工序已成为其中一项主要着眼点。现代制造业与工业已离不开能源消耗。随着全球人口不断膨胀,生活水平提升与经济日益增长正将...

能源成本不断走高,通过分析切削设备刀具能源消耗与切削工序,可确定能效提升的具体方法;同时,优化刀具和切削工序已成为其中一项主要着眼点。现代制造业与工业已离不开能源消耗。随着全球人口不断膨胀,生活水平提升与经济日益增长正将能源消耗推向更高峰。然而,煤炭、石油和生物燃料等能源正处于使用受限地步。在能源需求不断上扬的同时,众多局限也逐渐产生,这导致了能源成本的长期走高。在这样的大背景下,生产过程能源效率便成为今后实现现代制造业的技术推动力。然而,切削生产能源效率如何才能得

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The need for disciplinarity,interdisciplinarity and scientific societies-the cartographic perspective

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Geo-Spatial Information Science 2021年第1期24卷 160-166,I0017页

作者： jochen Schiewe Lab for Geoinformatics and Geovisualization(G2lab) HafenCity University of HamburgHamburgGermany

Do we still need Cartography?Do we still need a cartographic society?These questions,which can also be transferred to other disciplines,are answered from disciplinary and interdisciplinary perspectives-which creates an ideal connection to the networked and interdisciplinary thinking of Gottfried *** need for Cartography as a discipline is discussed based on a view on historic,current and future functions of maps and changing research and development *** respect to interdisciplinarity,Cartography shows connections to various domains while more and more relationships with young areas from the field of Computer Science are *** regard to cartographic societies,their central role and importance as networking platforms are ***,geographical and thematic granularities of societies as well as networking formats(including online versions)need to be evaluated and further developed on a constant basis.

关键词： Cartography map functions interdisciplinarity data classification point generalization professional societies

Yield Improvement and Advanced Defect Control——Driving Forces for Modeling of Bulk Crystal Growth

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Journal of Rare Earths 2006年第Z1期24卷 200-207页

作者： Georg Mueller jochen Friedrich Crystal Growth Laboratory University Erlangen-Nürnberg (WW6) and Fraunhofer Institute of Integrated Systems and Device Technology (IISB) Martensstrasse 7 D-91058 Erlangen Germany Crystal Growth Laboratory University Erlangen-Nürnberg (WW6) and Fraunhofer Institute of Integrated Systems and Device Technology (IISB) Martensstrasse 7 D-91058 Erlangen Germany

Yield improvement and advanced defect control can be identified as the driving forces for modeling of industrial bulk crystal growth. Yield improvement is mainly achieved by upscaling of the whole crystal growth apparatus and increased processing windows with more tolerances for parameter variations. Advanced defect control means on one hand a reduction of the number of deficient crystal defects and on the other hand the formation of beneficial crystal defects with a uniform distribution and well defined concentrations in the whole crystal. This "defect engineering" relates to the whole crystal growth process as well as the following cooling and optional annealing processes, respectively. These topics were illustrated in the paper by examples of modeling and experimental results of bulk growth of silicon (Si), gallium arsenide (GaAs), indium phosphide (InP) and calcium fluoride (CaF2). These examples also involve the state of the art of modeling of the most important melt growth techniques, crystal pulling (Czochralski methods) and vertical gradient freeze (Bridgman-type methods).

关键词： yield improvement advanced defect control crystal growth

Investigation of grain mass flow in a mixed flow dryer

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Particuology 2014年第1期12卷 33-39页

作者： Fabian Weigler jochen Mellmann Department of Post-harvest Technology Leibniz Institute for Agricultural Engineering Potsdam-Bornim

The numerical modeling of grain drying is a topic of great relevance to post-harvest engineering. The required type of drying process depends on the quantity of grain to be dried and the required quality of the grain. The choice of the drying system depends on the operating parameters of the drying process. The granular flow pattern of the material exerts a significant influence on the drying process. Post-harvest drying of grain is essential for better storage, handling, and processing. Therefore, it is important to know the material behavior that controls the particle flow patterns of grain in the drying equipment to guarantee the product quality and to optimize the drying process conditions. The discrete element method （DEM） was applied to investigate the particle flow pattern of wheat through a mixed-flow dryer （MFD） without airflow, and the findings were compared with experimental results in this work. The investigations were performed using dry wheat with 14 wb% moisture content.

关键词： Keywords:Mixed-flow dryerGrain mass flowDiscrete element method

Comparison of three different CFD methods for dense fluidized beds and validation by a cold flow experiment

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Particuology 2016年第6期14卷 34-47页

作者： Alexander Stroh Falah Alobaid Max Thomas Hasenzahl] jochen Hilz jochen Strohle Bernd Epple Technische Universitdt Darmstadt Institute for Energy Systems and Technology Otto-Berndt-Straβe 2 64287 Darmstadt Germany

This work focuses on a comparison between three different numerical CFD methods, namely Euler-Euler, Euler-Lagrange-stochastic, and Euler-Lagrange-deterministic, to treat a dense spouted bed, A simple cold flow experiment was used to investigate the hydrodynamics of a gas-solid flow in a three dimensional lab-scale spouted bed, In this context, two different air mass flow rates, 0,005 and 0.006 kg/s, were applied during fluidization. The experimental bed behaviour was recorded with a high-speed camera to validate the numerical predictions in terms of bubble size, bed expansion rate, and particle velocities at different reactor heights. The numerical setup was kept similar between all three modelling approaches, At both gas mass flow rates all three approaches are able to capture the overall bed expansion. However, at higher gas mass flow rates, discrepancies between experiment and simulation increase for the Euler-Euler and Euler-Lagrange-stochastic models. The Euler-Lagrange deterministic model most accurately predicts the flow pattern at both mass flow rates. The main reasons for discrepancies between simulation and experiment result from modelling of the collision and friction forces.

关键词： Computational fluid dynamics Euler-Lagrange-deterministic collisionmodel Euler-EulerMP-PIC approach Experimental validation

The Mechanism of Ground Granulated Blastfurnace Slag Preventing Alkali Aggregate Reaction

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Journal of Wuhan University of Technology(Materials Science) 2010年第2期25卷 332-341页

作者： STARK jochen FREYBURG Ernst F A Finger-Institute for Building Material Science of Bauhaus-University Weimar

Three different methods were applied to study the alkali content of gelpores in cement. In the closed system, the concentration of K＋, Na＋ and OH - have not reduced with the increase of age. In the open system, the diffusion and transferring of K＋ and Na＋ towards free space leads to the de-crease of total alkali content. In the micro-analysis system, the contents of K＋ and Na＋ in the first hy- drated layer of ground granulated blastfurnace slag （GBFS） are very low, while the contents of calcium and magnesium are relatively high. This phenomenon shows that the mechanism of GBFS preventing alkali aggregate reaction （AAR） is： when GBFS is dissolved by alkali medium, SiO2 and Al2O3 are dissolved into the cement matrix, then around GBFS particles form reaction rings rich in Ca2＋ and Mg^2＋, and the C-S-H gel of positive charges formed in the area repulses K＋ and Na＋, which are forced to transfer to the mortar＇s matrix, pore or mortar sample surface. The transferred K ^＋ and Na^＋ form alkali gel products with other dissolved ions, then become evenly distributed in the mortar sample and react with Ca（OH）2 in pore solutions to form （Na,K）x-2z·zCa·（SiO2）y·（OH）x gel products; and thus changes the AAR gel products＇ structure. The gel products will not expand, and so they can delay expansion destruction.

关键词： granulated blastfurnace slag (GBFS) alkali aggregate reaction (AAR) alkali content preventing mechanism

Improved dynamic testing by impedance control

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Earthquake Engineering and Engineering Vibration 2011年第3期10卷 423-435页

作者： jochen Carl Mettupalayam V. Sivaselvan Department of Civil Environmental and Architectural EngineeringUniversity of Colorado at Boulder

In this paper, the issue of actuator-structure interaction in dynamic testing of structures is considered. The problem is approached from the novel standpoint of impedance control. It is shown that an effective strategy to design controls for dynamic testing is by designing the test system impedance. It is also shown that this can be achieved using feedforward compensation. The analysis is carried out in the context of displacement controlled dynamic testing, when the tested structure has a high and nonlinear stiffness. It is demonstrated that stable and accurate dynamic testing can be achieved using the proposed strategy, when this is not possible using traditional feedback control techniques. Furthermore, the impedance control and feedforward strategies are applied in the context of hybrid simulation, a technique of coupling computational and physical substructures applied in earthquake engineering. Here, a delay compensation scheme is necessary in addition to feedforward. Experimental results are presented that demonstrate both improved dynamic testing performance when impedance control is employed, and its applicability in hybrid simulation.

关键词： dynamic test actuator-structure interaction impedance control hybrid simulation feedforward strategy

One photon-per-bit receiver using near-noiseless phase-sensitive amplification

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Light(Science & Applications) 2020年第1期9卷 543-549页

作者： Ravikiran Kakarla jochen Schroder Peter A.Andrekson Photonics Laboratory Department of Microtechnology and Nanoscience(MC2)Chalmers University of Technology412-96 GothenburgSweden

Space communication for deep-space missions,inter-satellite data transfer and Earth monitoring requires high-speed data *** reach is fundamentally dictated by the available transmission power,the aperture size,and the receiver sensitivity.A transition from radio-frequency links to optical links is now seriously being considered,as this greatly reduces the channel loss caused by diffraction.A widely studied approach uses power-efficient formats along with nanowire-based photon-counting receivers cooled to a few Kelvins operating at speeds below 1 Gb/***,to achieve the multi-Gb/s data rates that will be required in the future,systems relying on pre-amplified receivers together with advanced signal generation and processing techniques from fibre communications are also *** sensitivity of such systems is largely determined by the noise figure(NF)of the pre-amplifier,which is theoretically 3 dB for almost all ***-sensitive optical amplifiers(PSAs)with their uniquely low NF of 0 dB promise to provide the best possible sensitivity for Gb/s-rate long-haul free-space ***,we demonstrate a novel approach using a PSA-based receiver in a free-space transmission experiment with an unprecedented bit-error-free,black-box sensitivity of 1 photon-per-information-bit(PPB)at an information rate of 10.5 Gb/*** system adopts a simple modulation format(quadrature-phase-shift keying,QPSK),standard digital signal processing for signal recovery and forward-error correction and is straightforwardly scalable to higher data rates.

关键词： receiver amplifier noise