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991.
本文着重介绍了用Caivet微量热量计在298.15K下测定了20种M(NTO).·mH_2O(M=金属;NTO=3-硝基-1.2.4-三唑-5-酮;M=Li,n=1,m=2:M=Na,K,n=1,m=1;M=Mg.Mn,Co,Ni,n=2,m=8;M=Ca,n=2,m=4;M=Ba,n=2,m=3;M=Y、Yb,n=3,m=6;M=La,Ce,Pr.Sm,Eu,Gd,n=3,m=7;M=Nd,n=3,m=8;M=Tb;Dy,n=3;m=5)在水中的溶解焓和KNTO·H_2O(cr)与CuSO_4(aq)、Pb(NO_3)_2(aq)和Zn(NO_3)_2(aq)的沉淀反应焓.利用测得的溶解焓和沉淀反应治数据,计算了这20种M(NTO)_n·mH_2O和3种沉淀反应产物(Cu(NTO)_2·2H_2O,Pb(NTO)_2·H_2O和Zn(NTO)_2·H_2O)的标准生成焓。用Kapustinskii公式计算了20种M(NTO)_n(M=Li.Na,K,n=1;M=Mg,Ga,Mn,Co,Cu,Zn,n=2;M=Y,La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Yb.n=3)的晶格能,进而算出了它们 相似文献
992.
D. N. Buckley 《Journal of Electronic Materials》1988,17(1):15-20
A 1.4-μm thick InGaAs layer exhibiting an x-ray diffraction linewidth of 18 arcs has been grown on an InP substrate. This is the best crystalline perfection ever reported for InGaAs, as far as the author
is aware. The effect of gas composition on lattice mismatch has been investigated for InGaAs layers grown under a variety
of conditions. An empirical equation has been developed which relates lattice mismatch(Δa/a) to metals ratio, mole fraction of AsH3 and mole fraction of HC1. Values of(Δa/a) calculated using this equation are in good agreement with experiment. The metals ratio for lattice match is shown to vary
linearly with the growth rate. This observation is shown to be consistent with mass transfer limitation in the gas phase.
As a further consequence, relationships between layer thickness uniformity and lattice mismatch uniformity and between growth
rate and gas composition are derived. 相似文献
993.
T. H. Glisson J. R. Hauser M. A. Littlejohn C. K. Williams 《Journal of Electronic Materials》1978,7(1):1-16
Energy band gap and lattice constant contours are presented for the nine quaternary alloys formed from Al, Ga, In and P, As,
Sb. The quaternary bandgaps were obtained using an interpolation formula proposed by Moonet al. The quater nary lattice constants were obtained by use of a linear interpolation technique using the binary lattice constants
as boundary values.
This work was supported by a research grant from the Office of Naval Research, Washington, D.C. 相似文献
994.
Hamid Reza?ZarandiEmail author Hamid?Sarbazi-AzadEmail author 《The Journal of supercomputing》2005,31(2):185-202
In this paper, a new cache placement scheme is proposed to achieve higher hit ratios with respect to the two conventional schemes namely set-associative and direct mapping. Similar to set-associative, in this scheme, cache space is divided into sets of different sizes. Hence, the length of tag fields associated to each set is also variable and depends on the partition it is in. The proposed mapping function has been simulated with some standard trace files and statistics are gathered and analyzed for different cache configurations. The results reveal that the proposed scheme exhibits a higher hit ratio compared to the two well-known mapping schemes, namely set-associative and direct mapping, using LRU replacement policy. 相似文献
995.
Bodo?RosenhahnEmail author Gerald?Sommer 《Journal of Mathematical Imaging and Vision》2005,22(1):27-48
2D-3D pose estimation means to estimate the relative position and orientation of a 3D object with respect to a reference camera system. This work has its main focus on the theoretical foundations of the 2D-3D pose estimation problem: We discuss the involved mathematical spaces and their interaction within higher order entities. To cope with the pose problem (how to compare 2D projective image features with 3D Euclidean object features), the principle we propose is to reconstruct image features (e.g. points or lines) to one dimensional higher entities (e.g. 3D projection rays or 3D reconstructed planes) and express constraints in the 3D space. It turns out that the stratification hierarchy [11] introduced by Faugeras is involved in the scenario. But since the stratification hierarchy is based on pure point concepts a new algebraic embedding is required when dealing with higher order entities. The conformal geometric algebra (CGA) [24] is well suited to solve this problem, since it subsumes the involved mathematical spaces. Operators are defined to switch entities between the algebras of the conformal space and its Euclidean and projective subspaces. This leads to another interpretation of the stratification hierarchy, which is not restricted to be based solely on point concepts. This work summarizes the theoretical foundations needed to deal with the pose problem. Therefore it contains mainly basics of Euclidean, projective and conformal geometry. Since especially conformal geometry is not well known in computer science, we recapitulate the mathematical concepts in some detail. We believe that this geometric model is useful also for many other computer vision tasks and has been ignored so far. Applications of these foundations are presented in Part II [36].Bodo Rosenhahn gained his diploma degree in Computer Science in 1999. Since then he has been pursuing his Ph.D. at the Cognitive Systems Group, Institute of Computer Science, Christian-Albrechts University Kiel, Germany. He is working on geometric applications of Clifford algebras in computer vision.Prof. Dr. Gerald Sommer received a diploma degree in physics from the Friedrich-Schiller-Universität Jena, Germany, in 1969, a Ph.D. degree in physics from the same university in 1975, and a habilitation degree in engineering from the Technical University Ilmenau, Germany, in 1988. Since 1993 he is leading the research group Cognitive Systems at the Christian-Albrechts-Universität Kiel, Germany. Currently he is also the scientific coordinator of the VISATEC project. 相似文献
996.
Simone?OrcioniEmail author Massimiliano?Pirani Claudio?Turchetti 《Multidimensional Systems and Signal Processing》2005,16(3):265-284
This paper concerns the identification of nonlinear discrete causal systems that can be approximated with the Wiener–Volterra series. Some advances in the efficient use of Lee–Schetzen (L–S) method are presented, which make practical the estimate of long memory and high order models. Major problems in L–S method occur in the identification of diagonal kernel elements. Two approaches have been considered: approximation of gridded data, with interpolation or smoothing, and improved techniques for diagonal elements estimation. A comparison of diagonal elements estimated, with different methods has been shown with extended tests on fifth order Volterra systems.First Online Version Published in July, 2005 相似文献
997.
Software release planning for evolving systems 总被引:1,自引:0,他引:1
998.
999.
根据结构分析原理,建立了宏观和微观系统的竞争力模型,确定了各模型的评价指标体系,对一些指标进行了简化处理,给出了定性指标的量化处理方法,应用扣分法解决了大系统的评分难题,应用层次分析的方法建立了模型的判别矩阵,讨论了相对重要度的计算方法. 相似文献
1000.
Title of program: LATTICE Catalogue number: AARH Listing available from: CPC Program Library, Queen's University of Belfast, N. Ireland (see application form in this issue) Computer: CDC CYBER 205; Installation: CYBERNET Data Center, Minneapolis, MN, USA (test run was executed on the system when it was being checked out) Operating system: CYBER 200 O.S. Programming language used: CYBER 200 FORTRAN High speed storage required: 65–256 K (virtual memory system) Number of bits in a word: 64 Overlay structure: none Number of magnetic tapes required: none Other peripherals used: card reader, line printer Number of cards in combined program and test deck: 662 Card punching code: CDC 相似文献