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901.
J. A. Wolny S. Rackwitz A. I. Chumakov I. Faus H. Huang R. Rüffer K. Schlage H.-C. Wille V. Schünemann 《Hyperfine Interactions》2014,226(1-3):193-197
The nuclear inelastic scattering signatures of the low spin centres of the methanosulphonate, tosylate and perchlorate salts of the spin crossover polymer ([Fe(II)(4-amino-1,2,4-triazole)3]+2) n have been compared for the pure low-spin phase, for the mixed high-spin and low-spin phases, as well as for Zn(II) diluted samples. Within this series a change in the spectral pattern in the 320–500 cm?1 region is observed involving the decrease of the intensities of a band at ~320 cm?1 and those over 400 cm?1 as the molar fraction of the low-spin centres decreases. On the basis of the DFT calculations (B3LYP/CEP-31G) this effect is interpreted in terms of vibrational coupling of the iron centres of the same spin. 相似文献
902.
903.
阐述基于Mie散射理论和激光技术而研制的云粒子探测仪的相关问题。利用m量级的小孔光阑模拟感应区域的散射光,并对系统的探测敏感区域面积进行测定;通过使用不同直径的标准粒子对系统进行标定,得到可靠的响应曲线,用于定量测量云粒子尺度谱及粒子数密度。在进行了一系列实验室内的实验之后,将仪器装载在飞机上进行穿云飞行测量实验,表明了该仪器在飞行过程中工作正常、稳定,并且能够即时地显示采样区内云粒子尺度谱分布和数浓度;通过分析探测得到的数据,并与云粒子谱分布进行比较,确认了探测数据有效可靠,反映了该仪器具有良好的测云能力。 相似文献
904.
Shou-Hsuan Stephen Huang 《BIT Numerical Mathematics》1986,26(4):442-450
A new data structure called ordered priority queue is introduced in this paper. Elements stored in the data structure have a primary order (key) and a secondary order (priority) associated with them. An ordered min-priority queue allows users to find the minimum priority element in any range (according to key order) inO(logn) time. Such a data structure withn elements can be created inO(n logn) time usingO(n) storage. A specific implementation based on median split trees is presented. Sequential access of the elements can be done inO(n log logn) time andO(logn) extra storage.This work was supported in part by NASA under grant NAG 5-739. 相似文献
905.
最佳粮库地址的选择 总被引:1,自引:2,他引:1
管理部门通常要选择适当的地方建造粮库 ,所需服务范围已知 ,各部门运输量给定 .需为他们选择合适的地方 ,使总运费最少 .某乡的九个村 (A,B,C,… ,H,I)如图 1 ,各村距离给出 ,并标明它们各自上缴公粮数 .管理部门希望在村内或道路上建立一个粮库 ,最大限度地减少运输费用 .问题的解法有几种方案 ,对于本题来说 ,穷举搜索法是可行的 .另外 ,我们提出一种分析求解法 ,可找到优化解 .它利用图论的基础知识先求出图 1的各顶点间的最小路径 ,再进一步求出图的绝对中心 (即粮库的地址 ) ,其中的有关计算利用了 C++语言程序 .在此基础上 ,还可对问题的参数作更精细的分析 .概括地说 ,穷举搜索法对于简单的区域是行之有效的 .但对于更加一般化的问题 ,利用计算机可快捷准确地得到答案 .通过建立模型 ,我们得到下面两个结论 :(1 )我们找到最优解是 E点 ,其总运费为 1 2 775元 .(2 )模型具有广泛性 ,对于更一般的区域 ,可利用计算机总可以求出最优解 . 相似文献
906.
Zheng-da Huang 《计算数学(英文版)》2000,(5)
1. IntroductionLetf(x) = 0 (1.1)where j: X - Y is a norilineax operator which maps Banach space X into Baaedspace Y. The well-known iteration methods for solving (1.1) are the Nixon methodaam very ldnds of its improvement methods. One of them is the so called King-Wernerm6thod denned bykw(p, x03 yo):which is established by King in [7], Werner in [12] in d~nt formulas, respectively.It is interesting that the method (1.2) is of order 1 fi with the same functioncompotatinn coSt and twO ti… 相似文献
907.
The mobility of self-interstitials in α-zirconium (α-Zr) is studied with molecular dynamic (MD) and molecular static (MS)
simulations, using Ackland’s many-body inter-atomic potential. The basal crowdion configuration is found to be the ground
state. Four types of diffusion jumps can be identified via MS, in-plane in-line, in-plane off-line, out-of-plane in-line and
out-of-plane off-line. The in-plane migration is dominated by one-dimensional crowdion motion along the [110] directions, interrupted from time to time by off-line or out-of-plane jumps. Based on the MS results, the activation energies
and pre-exponentials for the diffusion processes are determined by fits to the Arrhenius plots of Dc and Da. The diffusional anisotropy factor Dc/Da is also obtained, and compares well with experimental results. The mean frequency of each type of jumps is then found using
Monte Carlo simulation, and is reported as a function of temperature. The mean lifetime and mean free path of the one-dimensional
mobility are then obtained. The 1-D mean free path is found to be unimportant for sink separations involved under the usual
irradiation damage conditions.
Received: 4 March 2002 / Accepted: 4 April 2002 / Published online: 10 September 2002
RID="*"
ID="*"Corresponding author. E-mail: Chung.Woo@polyu.edu.hk 相似文献
908.
Stereoscopic imaging and reconstruction technique is introduced to reconstruct the flame structures that are subject to acoustic excitation. The laminar diffusion flame under investigation was created in a cylindrical tube and excited by a loudspeaker. Stereo images were taken at a shutter speed of 1/10000th second using a ‘stereo camera’ and the depth cue of the flame structures along the camera viewing direction were then computed using machine vision methodology. By visualizing the computed three-dimensional flame models, as well as judging the corresponding attribute such as surface gradient, the understanding of the flame and acoustic wave interaction could be improved. 相似文献
909.
S Robinson 《The Journal of the Operational Research Society》2005,56(6):619-629
Discrete-event simulation is one of the most popular modelling techniques. It has developed significantly since the inception of computer simulation in the 1950s, most of this in line with developments in computing. The progress of simulation from its early days is charted with a particular focus on recent history. Specific developments in the past 15 years include visual interactive modelling, simulation optimization, virtual reality, integration with other software, simulation in the service sector, distributed simulation and the use of the worldwide web. The future is then speculated upon. Potential changes in model development, model use, the domain of application for simulation and integration with other simulation approaches are all discussed. The desirability of continuing to follow developments in computing, without significant developments in the wider methodology of simulation, is questioned. 相似文献
910.
M S Rauner S C Brailsford S Flessa 《The Journal of the Operational Research Society》2005,56(2):222-233
HIV/AIDS affects over 40 million people worldwide, and more than 70% of these people live in Africa. Mother-to-child transmission of HIV accounts for over 90% of all HIV infections in children under the age of 15 years. However, implementing HIV prevention policies in Africa is extremely difficult because of the poor medical and socio-economic infrastructure. In this paper, we present a discrete-event simulation model that evaluates the relative benefits of two potentially affordable interventions aimed at preventing mother-to-child transmission of HIV, namely anti-retroviral treatment at childbirth and/or bottlefeeding strategies. The model uses rural Tanzanian data and compares different treatment policies. Our results demonstrate that strategic guidelines about breastfeeding are highly dependent on the assumed increase in infant mortality due to bottlefeeding, the efficacy of anti-retroviral treatment at childbirth, and the maternal health stage. The cost of averted infections, though low by Western standards, may represent significant obstacles to policy implementation in developing countries. 相似文献