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31.
为全面了解我国建筑业企业国际化的发展水平,基于三维体积模型对中国建筑业企业国际化发展所处的阶段进行客观解释,运用有序Probit模型对影响我国建筑业企业国际化发展的因素进行回归分析,找出其主要影响因素、显著影响及不显著因素。在此基础上,结合蛛网模型将中国各省建筑业企业国际化发展水平进行比较研究,并提出中国建筑业企业国际化发展的政策建议,为提高我国建筑业企业的国际化发展水平提供了有益借鉴。 相似文献
32.
Ronit Bitton Lesley W. Chow R. Helen Zha Yuri S. Velichko E. Thomas Pashuck Samuel I. Stupp 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(3):500-505
Self‐assembling peptide amphiphiles (PAs) can form hierarchically ordered membranes when brought in contact with aqueous polyelectrolytes of the opposite charge by rapidly creating a diffusion barrier composed of filamentous nanostructures parallel to the plane of the incipient membrane. Following this event, osmotic forces and charge complexation template nanofiber growth perpendicular to the plane of the membrane in a dynamic self‐assembly process. In this work, we show that this hierarchical structure requires massive interfacial aggregation of PA molecules, suggesting the importance of rapid diffusion barrier formation. Strong PA aggregation is induced here through the use of heparin‐binding PAs with heparin and also with polyelectrolytes of varying charge density. Small angle X‐ray scattering shows that in the case of weak PA‐polyelectrolyte interaction, membranes formed display a cubic phase ordering on the nanoscale that likely results from clusters of PA nanostructures surrounded by polyelectrolyte chains. 相似文献
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Certain type of linguistic terms such as satisfactory, good, very good and excellent have an order among them. In this paper we introduce a new concept of soft sets with some order among the parameters. Some properties of lattice ordered soft sets are given. Lattice ordered soft sets are very useful in particular type of decision making problems where some order exists among the elements of parameters set. 相似文献
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We have developed stacked nanocarbon polymer actuators that are composed of several nanocarbon polymer actuator films using nonwoven fabric as insulation layers. The nonwoven fabric prepared through electrospinning methods has extremely-low-density structures, which do not significantly prevent the motions of each nanocarbon actuator layer. Therefore, stacking several thin nanocarbon polymer actuators using nonwoven fabric as insulation layers is expected to increase generated force without decreasing the displacement of a one-layer actuator. We have prepared stacked actuators with one, two, three, four, and seven layers using this method. The displacement and blocking force of these actuators are measured and compared with those of one-layer actuators of different thicknesses. Displacement is weakly dependent on the thickness of the actuator films of the stacked actuators. On the contrary, it decreases considerably as the thickness of the actuator film of the one-layer actuator increases. In both cases, blocking force is proportional to the thickness of actuator films. We have developed a stacked actuator model based on a trilayer actuator model and confirmed the experimental results using the model. 相似文献
38.
Multicriteria decision-making problems have been applied to many applications for its practicality. Nevertheless, when the evaluated satisfactions are more complex, such as interval-valued distributions, how to reasonably obtain the aggregation results of alternatives is still an open issue. In this paper, an interval-valued exceedance method is proposed to solve such a question based on the Golden Rule representative value and probabilistic exceedance method. Due to good performance of expressing uncertain information, the Golden Rule representative value method is used to order interval-valued satisfactions after an effective normalization process. In addition, a quantifier-based ordered weighted averaging operator is also introduced to consider the preferences of decision makers. A realistic application of supplier selection is shown to illustrate the practicality of the proposed method. 相似文献
39.
Microstructure and mechanical properties of the Mg–13Gd–5Er–1Zn–0.3Zr alloy were investigated by optimal microscope (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray spectrometer (EDS) and transmission electron microscopy (TEM) in the present investigation. The results suggested that the basal plane stacking faults (SF) of Mg crystal was present together with the precipitation of the (Mg,Zn)5(Gd,Er) phase. The parts of the (Mg,Zn)5(Gd,Er) precipitate were dissolved into the matrix during homogenization treatment at 733 K. In addition, a new kind of lamellar-shaped 14H long-period stacking-ordered (LPSO) structure was precipitated from the stacking faults of basal plane during homogenization treatment at 733 K. However, the unstable β′ phase was precipitated in the extruded grains after ageing treatment. The presence of both the 14H-LPSO structure and the β′ precipitate resulted in a great enhancement in mechanical properties. The values of the tensile yield strength and ultimate tensile strength were 338.8 MPa and 410.9 MPa, respectively. 相似文献
40.
With the advent of Big Data era has seen both the volumes and update rates of data increase rapidly. The granular structure of an information system is evolving with time when redundancy data leaves and new data arrives. In order to quickly achieve the rough approximations of dynamic attribute set interval-valued ordered information system that the attribute set varies over time. In this study, we proposed two dynamic computing rough approximations approaches for time-evolving information granule interval-valued ordered information system which induced by the deletion or addition some attributes, respectively. The updating mechanisms enable obtaining additional knowledge from the varied data without forgetting the prior knowledge. According to these established computing rules, two corresponding dynamic computing algorithms are designed and some examples are illustrated to explain updating principles and show computing process. Furthermore, a series of experiments were conducted to evaluate the computational efficiency of the studied updating mechanisms based on several UCI datasets. The experimental results clearly indicate that these methods significantly outperform the traditional approaches with a dramatic reduction in the computational efficiency to update the rough approximations. 相似文献