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将纸折叠12次

新知客 2010年第9期 103-103页

作者： dr karl RAINER

因为厚度会按几何级数的方式增加,一度有"一张纸不能被折叠超过7次"的说法,但是有人不相信,并真的推翻了这一说法。当我的儿子临近小学毕业时,我想已经是时候将我怪异又很有趣的科学智慧传授给他了。我对他说。

关键词：小学毕业能将给你希梅内斯数学老师材料厚度次比大型购物中心数学问题文学奖获得者

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在创新上投资的安全性

国内外机电一体化技术 2010年第8期13卷 27-27页

作者： dr．karl Tragl 王锡俊（翻译）博世力士乐集团 SERCOS中国办事处

新一代专用于SERCOS Ⅲ的Anybus—CC通讯模块，简化了SERCOS Ⅲ通信接口的开发，并节省了70％的开发成本。

关键词：安全性 SERCOS 投资创新开发成本通讯模块通信接口

Dedicated to Professor dr.-Ing. ***.h.c. Jurgen Zierep for his 80^(th) birthday Pattern Formation in Rotating Fluids

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Journal of Thermal Science 2009年第2期18卷 109-118页

作者： karl Bühler Department of Mechanical and Process Engineering University of Applied Sciences

Flows in nature and technology are often associated with specific structures and pattern. This paper deals with thedevelopment and behaviour of such flow pattern. Flow structures are important for the mass, momentum and energytransport. The behaviour of different flow pattern is used by engineers to obtain an efficient mass and energyconsumption. Mechanical power is transmitted via the momentum of rotating machine parts. Therefore thephysical and mathematical knowledge of these basic concepts is important. Theoretical and experimental investigationsof principle experiments are described in the following. We start with the classical problem of the flowbetween two concentric cylinders where the inner cylinder rotates. Periodic instabilities occur which are calledTaylor vortices. The analogy between the cylindrical gap flow, the heat transfer in a horizontal fluid layer exposedto the gravity field and the boundary layer flow along concave boundaries concerning their stability behaviour isaddressed. The vortex breakdown phenomenon in a cylinder with rotating cover is also described. A generalizationto spherical sectors leads then to investigations with different boundary conditions. The spherical gap flowexhibits interesting phenomena concerning the nonlinear character of the Navier-Stokes equations. Multiple solutionsin the nonlinear regime give rise to different routes during the laminar-turbulent transition. The interactionof two rotating spheres results in flow structures with separation and stagnation lines. Experimental results areconfirmed by numerical simulations.

关键词： Rotating Fluids Stability Behaviour Bifurcation Vortices Laminar-turbulent Transition

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Insect Science 2008年第4期15卷 369-374页

作者： karl Kral Institute of Zoology KarI-Franzens-University Graz A-8010 Graz Austria

The peering-jump behavior was studied for the common field grasshopper Chorthippus brunneus, the meadow grasshopper C. parallelus and the alpine grasshopper Miramella alpina （Orthoptera, Caelifera）. It was found that immediately before jumping M. alpina executes primarily unilateral object-related peering movements, with approximately twice the amplitude and velocity of the predominantly bilateral object-related peering movements of the other two species. Whereas M. alpina almost always jumped toward the black stripes in the experimental arena, the other species jumped toward both the black stripes and the white spaces between them. All three species preferred the same pattern of black stripes, which permitted them to view one black stripe frontally, with an additional black stripe to the left and right, in the lateral visual field. The similarities and differences in the peering-jump behavior of the three grasshopper species is discussed with regard to visual perception （parallax cues） and environmental adaptation.

关键词： Chorthippus environmental adaptation grasshopper jumping Miramella,peering phototaxis scototaxis

A high-resolution history of vegetation and climate history on Sunda Shelf since the last glaciation

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Science China Earth Sciences 2007年第1期50卷 75-80页

作者： karl STATTEGGER Institute of Geosciences University of Kiel Olshausenstrasse 40 Kiel 24118 Germany

This paper presents 16500-year-long high-resolution pollen and spore records from sediments of core 18287 on the continental slope of the southern South China Sea. In the period of 16.5―13.9 ka B.P., the low-mountain rainforest dominated the continental slope of the South China Sea. And in the period of 13.9―10.2 ka B.P., the lowland rainforest and ferns expanded greatly, while the low-mountain rainforest shrank, which indicated a warming at the last deglaciation. Also during this period, the pollen sedi-mentation rates reduced sufficiently. This might imply a rise of the sea level and therefore the sub-mergence of the shelf, resulting in the broadening of the distance between the source area and the slope. After 10.2 ka B.P, decreasing of the fern indicates the early Holocene (10.2―7 ka B.P.) is a cold period, while the increasing of fern marks the rising temperature (7―3.6 ka B.P.).

关键词： Sunda Slope pollen and spores vegetation last deglaciation Holocene.

Pattern Formation Around Interacting Bodies in Rotating Fluids

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Journal of Thermal Science 2006年第2期15卷 132-134页

作者： karl BHLER University of Applied Sciences Badstrasse 24 D-77652 Offenburg Germany

The interaction of bodies like spheres and disks in rotating fluids leads to novel flow structures. The primary swirling flow in circumferential direction is superimposed by a secondary motion in the meridional plane. The flow is visualized by introducing ink through a hole in the center of the axes and distributed radially in the central plane between the interacting bodies. The flow structure depends on the shape of the bodies, their geometrical arrangement and the Reynolds number given by the rotational speed. The observed flow structures gave rise to further investigations with PIV-measurcments and numerical simulations.

关键词： Rotating fluids pattern formation recirculation zones interacting bodies flow visualization

AN OUTLINE OF THE VARIETIES OF THE SECOND-ORDER SYSTEMS SCIENCES

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Journal of Systems Science and Systems Engineering 2017年第3期26卷 383-412页

作者： karl H. Muller International Academy for Systems Science and Cybernetics Steinbeis Transfer Center New Cybernetics Vienna Austria

The systems sciences are based on a universal language of systems which can be used within most academic disciplines in their endeavors for exploring the world. Currently, systems sciences cover a wide variety of different approaches like complex adaptive systems, resilient systems or systems engineering. One of the future extensions of the systems sciences comes through the applications of second-order systems science as a new field of reflexive studies on first-order systems science. This article provides a general background on the relations of first-order science and second-order science in general and then goes on to sketch a basic outline for the second-order systems sciences and their potentials for quality control and for innovations for the first-order systems sciences.

关键词： Optimization

Vibrational Analysis of Oxygen Adsorption on Cs and CO Coadsorbate Precovered Ru(0001)Surface

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Chinese Physics Letters 1999年第6期16卷 428-430页

作者： HE Pei-mo karl Jacobi Department of Physics Zhejiang UniversityHangzhou 310027 Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6D-14195 BerlinGermany

Vibrational analysis of oxygen adsorption on the Cs and CO coadsorbate precovered Ru(0001)surface was carried out by means of high-resolution electron energy loss *** submonolayer Cs coverages on Ru(0001)j an appropriate amount of CO adsorption leads to formation of(2x2)-Cs+2CO *** oxygen adsorption on this Cs and CO coadsorbate precovered surface results in a remarkable change of high-resolution electron energy loss *** loss peak of C-O stretch mode for 2x2 island species decreases in intensity,which is accompanied by appearance of new bands at about 87 and 240 *** results show that Cs adatoms and CO molecules are rearranged upon oxygen adsorption,and are correlated with coexistence of bare surface CO and a mixed phase of Cs,CO,and O.

关键词： spectroscopy. adsorption Adsorption

High-Resolution Electron Energy Loss Spectroscopy of Cs Vibration on the Ru (0001) Surface

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Chinese Physics Letters 1998年第12期15卷 907-909页

作者： HE Pei-mo karl Jacobi Department of Physics Zhejiang UniversityHangzhou 310027 Fiitz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6D-14195 BerlinGermany

By using a newly implemented high-resolution electron energy loss spectrometer with better resolution,a new loss at a energy near to double energy of the Cs-Ru stretching vibration,and its dependence on Cs coverage for Cs overlayer on Ru(0001)were *** the energy is slightly smaller than the double energy of the Cs-Ru vibration(intrinsic loss),overtone excitation must be responsible for this new loss observed,but two-phonon process is not excluded.

关键词： stretching Electron slightly