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101.
一种三叉树的存储结构及其基本操作的实现 总被引:3,自引:0,他引:3
本文在文献[1]所给出的有关三叉树有其相关概念的基础上,提出了一种新的三叉树存储结构,即“儿子-兄弟链表”方法,并在这种结构下,对三叉树的基本操作的实现算法进行了较详细的讨论。 相似文献
102.
G. Bartolini A. Ferrara 《International Journal of Adaptive Control and Signal Processing》1992,6(3):237-246
In this paper we pursue a twofold aim. First we want to simplify the complexity of the classical Monopoli's scheme, the so-called ‘Augmented error signal control scheme’. Then we also wish to cope with the realistic situation in which the presence of unmodelled dynamics has to be taken into account. This latter problem has been faced in the literature by suitably modifying the adaptation mechanism in order to avoid undesired phenomena as well as to obtain an attractive stability region for the state trajectories starting from any point in a predefined initial condition set. In our case the necessity of introducing any sort of modification in the adaptation mechanism is completely avoided, but we still obtain asymptotic stability of the output error signal. 相似文献
103.
This paper presents a new computerized procedure for dealing with the design of horizontal ground heat exchangers (HGHE). The computer program is based on the transient model of coupled nonlinear partial differential equations governing heat and mass flow in soils. The model is two-dimensional and delineates the operation of ground heat storage with the HGHE and such phenomena as freezing/thawing and drying/rewetting of soil moisture. Comprehensive climatological data, such as ambient temperature, solar radiation, wind velocity, rainfall, snowfall, snow characterstics, and water vapour pressure is used to simulate conditions at the ground surface over any required length of time. The package can be applied to any geographical location by changing climatic and soil data input. The designer has the possibility of selecting any of 12 types of soils from sand to clay, 12 commercial heat pumps, nine different configurations of the HGHE, 16 plastic pipes for ground coils, and 13 ground coil fluids. The program, however, does not calculate the length of the HGHE but it evaluates the thermodynamic performance of a ground heat pump system and provides comprehensive data on thermal and hydraulic conditions in ground heat storage. The length of the ground heat exchanger is obtained from a line source theory model or from site dimensions and pipe spacing. Computed results for ground heat exchanger operation correlate fairly well with experimental data. Simulation of temperature and moisture content in the ground for natural conditions (no heat extraction/deposition) showed a fair agreement with field data. The entire computer program is user-friendly, interactive, menu-driven, and written in FORTRAN 77. 相似文献
104.
A cryo-specimen storage system for low-temperature scanning electron microscopy (LTSEM) specimens is described, which: liberates multi-specimen experiments from sampling restrictions imposed by the rate at which LTSEM specimens can be examined in the SEM; provides security against experiment loss resulting from breakdown of the SEM or cryo-system; enables collection of specimens in the field or in laboratories remote from the SEM laboratory; and facilitates international air transport of LTSEM specimens. The components of the system, which has a capacity of 98 stub-mounted specimens, are readily made in a laboratory workshop. The details of the design may be altered to suit particular specimen types or experimental approaches. 相似文献
105.
本文提出了一个深亚微米条件下的多层VLSMCM有约束分层层分配的遗传算法。该算法分为两步:首先进行超层分配,使各线网满足Crosstalk约束,且超层数目最少;然后进行各超层的通孔最少化二分层。与目前的层分配算法相比,该遗传算法具有目标全面,全局优化能力强等特点,是一种可应用于深亚微米条件下的IC CAD的有效分层方法。 相似文献
106.
Abstract— The yield criterion is interpreted as defining the metric of the stress space. Hydrostatic stresses correspond to null geodesies. The plastic strain increment represents a normal projection of the increment undergone by a certain scalar function (hardening function) which depends only on the distance between stress points. This establishes a flow rule formally equivalent to the Prandtl-Reuss equations. Consideration of un-loading processes leads to the analysis of equivalent paths and to the definition of a generalized length or separation which provides a new representation of kinematic hardening. 相似文献
107.
ChangLIU HuimingCHENG 《材料科学技术学报》2002,18(2):124-126
Single=walled carbon nanotubes(SWNTs) were synthesized by a hydrogen arc discharge method.A high yield of gram quantity of SWNTs per hour was achieved.Tow kinds of SWNT products:web-like substancea and thin films in large slices were obtained. Results of resonant Raman scattering measurements indicate that the SWNTs prepared have a wider diameter distribution and a larger mean diameter.Hydrogen uptake measurements of the two kinds of SWNT samples(both as prepared and pretreated) were carried out using a high pressure volumetric method,respectively.And a hydrogen storage capacity of 4 wt pct could be repeatedly achieved for the suitably pretreated SWMNTs,whicb indicates that SWNTs may be a promising hydrogen storge material. 相似文献
108.
本文从冗余磁盘阵列的信道模型出发,研究各部分组成的理论与技术。文中在给出系统的模型描述之后,着重分析了冗余信息元生与检纠错、数据分割与同步。还研究了系统中的负荷平衡问题,指出了磁盘优化调度的方向。 相似文献
109.
中针对变井储试井分析问题,给出了确定变井储系数及计算续流量的方法,并用反褶积分析积分析方法解释了未出现径向流的早期测压数据,给出了解决早期试井资料分析问题的有效方法。 相似文献
110.
浅谈抽水蓄能电站的特点及其优越性 总被引:2,自引:0,他引:2
本文介绍了国外抽水蓄能电站的发展过程与现状,修建抽水蓄能电站的八大优点。为了改善我省电力系统的运行条件,提出了在我省修建抽水蓄能电站的四点建议。 相似文献