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21.
In this paper we describe a fuzzy logic based approach to modelling uncertainty in class hierarchies. It is shown that the traditional view of class hierarchies is subsumed in this model as a special case. The problem of multiple inheritance in class hierarchies is discussed and analyzed. The membership value derivations in the inheritance hierarchy reflects the degree of fuzziness existing in the data values and the semantics of the situation being modelled. Thus a more realistic modelling of the universe of discourse is possible through this approach. This model is compatible with existing object-oriented data models.  相似文献   
22.
利用图形化模型理论,以及DNA数据,研究了一个在法庭上颇有争议的亲子鉴定问题.通过案例中的家谱图,建立Bayesian网络,根据遗传学的孟德尔定律,借助于Hug in软件,计算出网络中各结点的概率.在数学上,给出了一个可供法庭参考的合理推断.  相似文献   
23.
The dependence of the binding energies in molecules and crystals on the interatomic distances near the equilibrium position was established in the framework of the Mie equation using the force constants of molecules and the elasticity moduli of solids. To evaluate the repulsion forces, we used the Morse function for molecules and the Born-Landé approach for ionic crystals.  相似文献   
24.
为探寻刺参体色遗传的内在分子基础,运用Clontech SSH试剂盒分别构建了白化刺参和青刺参的正反向抑制性消减杂交文库;221个克隆测序分析确认了体色遗传差异性表达基因26个;GO分析显示这些差异基因分别隶属于核糖体基因、能量代谢、细胞结构、免疫调控、白化性状直接相关基因及未知基因.荧光定量PCR结果显示:ADP-核糖激化因子在白化刺参中相对表达量约是青刺参的2倍,而虾青素和小眼畸形转录因子在白化刺参中相对表达量则低于青刺参,分别为青刺参的0.38倍和0.47倍,相对表达量趋势和文库所得结果一致.该研究为进一步了解刺参体色分化及其优良性状的形成机制提供了基础资料.  相似文献   
25.
Inner‐shell electronic structures, properties and ionization spectra of DNA/RNA bases are studied with respect to their parent pyrimidine and purine species. Density functional theory B3LYP/aug‐cc‐pVTZ has been employed to produce the geometries of the bases, whereas LB94/et‐pVQZ//B3LYP/aug‐cc‐pVTZ is used to calculate site‐related Hirshfeld charges and core (vertical) ionization energies, as well as inner‐shell spectra of C1s, N1s and O1s for DNA/RNA bases and their parent pyrimidine and purine species. The site‐dependent variations of properties indicate the changes and inheritance of chemical environment when pyrimidine and purine become substituted. In general, although the changes are site‐dependent, they are also ring‐dependent. Pyrimidine bases change less significantly with respect to their parent pyrimidine than the purine bases with respect to their parent purine. Pyrimidine bases such as uracil, thymine and cytosine inherit certain properties from their parent pyrimidine, such as the Hirshfeld charge distributions and the order of core ionization energy level etc. No particular sites in the pyrimidine derivatives are engaged with a dramatic chemical shift nor with energy crossings to other sites. For the core shell spectra, the purine bases inherit very little from their parent purine, and guanine exhibits the least similarities to the parent among all the DNA/RNA bases.  相似文献   
26.
李晓愚 《高分子学报》2020,52(6):135-147
现代博物馆的陈列方式抹平了古代画作之间的时空差异,导致绘画的“历史语境”遭到破坏和误读。为了更好地传承古代艺术,我们应当从“收视点”的角度去考察画作,还原其最初被观看(或使用)的语境以及相应的观看方式。对画作“收视点”的重构有助于更深入地理解画作的功能、型制、含义和风格,亦可使现代人对创造和使用这些画作的古人多一分“了解之同情”。文字史料、图像再现和文学描述能为重构提供支持的证据,但这些证据必须被极其谨慎地使用。  相似文献   
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28.
This paper focuses on the issue plasticity within the framework of a micromechanical model for single-crystal shape-memory alloys. As a first step towards a complete micromechanical formulation of such models, we work with classical J2-von Mises-type plasticity for simplicity. The modeling of martensitic phase transitions is based on the concept of energy relaxation (quasiconvexification) in connection with evolution equations derived from inelastic potentials. Crystallographic considerations lead to the derivation of Bain strains characterizing the transformation kinematics. The model is derived for arbitrary numbers of martensite variants and thus can be applied to any shape-memory material such as CuAlNi or NiTi. The phase transition model captures effects like tension/compression asymmetry and transformation induced anisotropy. Additionally, attention is focused on the interaction between phase transformations and plasticity in terms of the inheritance of plastic strain. The effect of such interaction is demonstrated by elementary numerical studies.  相似文献   
29.
在设计面向对象有限元程序中运用了基于ANSI/ISOC 标准模板库 (STL)的技术,以向量模板类的特化继承对象为变容量数据容器,实现了可按计算实例的离散结点数量动态存取数据的机制和数据容器的零容量启动,从而避免了运算时系统对静态内存空间的超量占用。  相似文献   
30.
Advancing the sparse regularity method, we prove one‐sided and two‐sided regularity inheritance lemmas for subgraphs of bijumbled graphs, improving on results of Conlon, Fox, and Zhao. These inheritance lemmas also imply improved H‐counting lemmas for subgraphs of bijumbled graphs, for some H.  相似文献   
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