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111.
We present an extrapolation type algorithm for the numerical solution of fractional order differential equations. It is based
on the new result that the sequence of approximate solutions of these equations, computed by means of a recently published
algorithm by Diethelm [6], possesses an asymptotic expansion with respect to the stepsize. From this we conclude that the
application of extrapolation is justified, and we obtain a very efficient differential equation solver with practically no
additional numerical costs. This is also illustrated by a number of numerical examples.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
112.
On the Crossing Number of Circular Graphs 总被引:6,自引:0,他引:6
1.IntroductionInVLSIchipdesign,thetwo-layerroutingofgraphGplayanimportantrole.Thatis,theupperlayercanonlybeusedforverticalwiringandthesecondlaer,theloweroneonlyforhorizontalwiring.Soweconsidertheplanarprojectionofth.etwolayers,i.e.,consideratwodimensionalgridasapropergraphmodel.ThenoneobviousconditiontoberequiredisthateveryvertexofGhasitsdegreeatmost4.Withoutlossofgeneralitylweonlyconsider4regUlargraphs.IfGisaplanargraphwitha(G)S4,alinearalgorithmhadbeenprovidedforfindingarectilineajrrout… 相似文献
113.
W. Okumura Y. Ohkoshi Y. Gotoh M. Nagura H. Urakawa K. Kajiwara 《Journal of Polymer Science.Polymer Physics》2004,42(1):79-90
The structure, mechanical properties, and thermomechanical properties of poly(ethylene terephthalate) (PET) fibers obtained by laser-heated drawing were investigated in terms of their dependence on the draw ratio and feed speed and the differences between neck-drawn fibers and flow-drawn fibers. The long period at a draw ratio of 6.0 reached 19.0 nm, notably larger than at lower ratios, whereas the tilting angle of the laminar structure was constant at about 60°, regardless of the draw ratio. A maximum value of 15.0 GPa was attained for the initial modulus, and 1.07 GPa was attained for the tensile strength. A higher tensile strength orientation-induced crystallized fiber at the same initial modulus was obtained from higher molecular weight PET. The relationship between the compliance and molecular orientation of the amorphous phase was studied with a series model of crystalline and amorphous phases. The results revealed that, in the high-draw-ratio fibers, the compliance of the amorphous phase decreased with the draw ratio at a higher rate than indicated by extrapolation to intrinsic values. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 79–90, 2004 相似文献
114.
Ahmed Jalal Uddin Y. Ohkoshi Y. Gotoh M. Nagura R. Endo T. Hara 《Journal of Polymer Science.Polymer Physics》2004,42(3):433-444
Fibers of PA9‐T, a new semiaromatic polyamide containing a long aliphatic chain, were prepared by melt spinning. As‐spun fibers were subsequently drawn with a CO2 laser‐heated drawing system at different draw ratios and various drawing velocities. On‐line observations of drawing points deciphered two drawing states; namely, flow drawing and neck drawing, over the entire range of drawing. Drawing stress revealed that flow drawing is induced by slight drawing stress under a low draw ratio up to 3, and neck drawing is induced by relatively high drawing stress under a higher draw ratio. The effect of drawing stress and drawing velocity on the development of the structure and properties has been characterized through analysis of birefringence, density, WAXD patterns, and tensile, thermal, and dynamic viscoelastic properties. For the neck‐drawn fibers, almost proportional enhancements of crystallinity and molecular orientation with drawing stress were observed. The flow‐drawn fibers have an essentially amorphous structure, and birefringence and density do not always have a linear relation with properties. The fibers drawn at high drawing speed exhibit improved fiber structure and superior mechanical properties. The maximum tensile strength and Young's modulus of PA9‐T drawn fibers were found to be 652 MPa and 5.3 GPa, respectively. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 433–444, 2004 相似文献
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116.
J. F. B. M. Kraaijevanger 《BIT Numerical Mathematics》1985,25(4):652-666
We present upper bounds for the global discretization error of the implicit midpoint rule and the trapezoidal rule for the case of arbitrary variable stepsizes. Specializing our results for the case of constant stepsizes they easily prove second order optimal B-convergence for both methods.1980 AMS Subject Classification: 65L05, 65L20. 相似文献
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A simple and novel methodology was developed for manufacturing interdigitated asymmetric all-solid-state flexible micro-supercapacitors (MSCs) by a facile pencil drawing process followed by electrodepositing MnO2 on one of the as-drawn graphite electrode as anode and the other as cathode. 相似文献
120.
为解决目前接触式拉丝模具测量系统存在精度低、 响应时间长、测量参数不能实时采集、 传输和处理等问题,本文系统引入激光衍射旋转法进行拉丝模孔型的测量。本文测量系统主 要由机械、光学成像、数据采集处理及网络传输等4部分构成,在测量过程中不断 旋转拉丝模中心轴,在CCD上分别形成圆和椭圆的衍射图样,利用衍射图样和旋转角度 之间的函数关系实现拉丝模孔型参数的测量。同时,系统还将“互联网+”引入到系统中, 将 每一个拉丝模具作为一个节点,通过组网技术将其组成互联网测量系统,实现拉丝模测量数 据的实时采集、分析和处理。实验表明,本文测量系统精度可达到0.01mm,在拉丝模孔型测量中具用较高的工程实用价值。 相似文献