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1.
1. Introduction Seismic physical modeling technology is an important method for the research on seismic exploration theory and methods. In seismic physical experiments, the earth, mantle or field site are scaled down to physical models according to the similarity principle, and then the seismic field and its variation are observed in the laboratory for the research work on the theories and methods of the earth structure, earthquake forecasting, energy and mineral resource exploration, and engi… 相似文献
2.
Mou Weimin; Biocca Frank; Owen Charles B.; Tang Arthur; Xiao Fan; Lim Lynette 《Canadian Metallurgical Quarterly》2004,10(4):238
In 3 experiments, the authors investigated spatial updating in augmented reality environments. Participants learned locations of virtual objects on the physical floor. They were turned to appropriate facing directions while blindfolded before making pointing judgments (e.g., "Imagine you are facing X. Point to Y"). Experiments manipulated the angular difference between the learning heading and the imagined heading and between the actual heading and the imagined heading. The effect of actual-imagined on pointing latency was observed for naive users but not for users with brief training or instructions concerning the fact that objects can move with body movements. The results indicated that naive users used an environment-stabilized reference frame to access information arrays, but with experience and instruction the nature of the representation changed from an environment stabilized to a body stabilized reference frame. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
The public information signs ( The term public information signs will be abbreviated to public signs in the following text.)in the urban areas not only offer convenience for people to move around, but also reflect the level of development and progress of those areas. It is essential to the creative development and uplifting of the New Costal Area (thereafter, NCA) to have a good understanding of its present situation with regard to its public signs, to discuss the related issues in the development, to work out a system that is up to international standard and develop its own standards in the course of implementing the national strategies on standardizing public signs. 相似文献
4.
沉积环境与多元统计综合分析法 总被引:1,自引:0,他引:1
本文首先根据地震资料提取了十二种地震参数,然后通过对LH油田TZ地区沙三上段下部地层进行沉积环境分析,确定了可能存在的沉积相类型,并用有序样品聚类的方法对过井和井旁地震测线按沉积相个数进行分割,由此而建立了该区各类沉积相的判别函数。通过这些判别函数,用逐步判别分析的方法,对该区其它地震测线的参数进行判别分类,最后搞清了研究区目的层的沉积相展布。通过分析和计算证明,这一方法对有地震资料的盆地或地区进行沉积相的划分,是行之有效的 相似文献
5.
本文阐述了氧化锆增韧陶瓷(ZTC)的相变增韧机理,并探讨了热处理工艺对ZTC的相变及显微组织的影响规律。 相似文献
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7.
磁性塑料卷材的研制与应用 总被引:1,自引:0,他引:1
磁性塑料卷材由CPE树脂、助剂以及磁粉、经塑炼、压延成型的一种柔性薄 强磁性材料。为使大量磁粉(约90Wt%-92Wt%)能均匀分散在少量树脂(约6Wt%-7Wt%)中,必须对磁粉的分散性及其颗粒形状等方面进行研究。 相似文献
8.
In this paper, the dynamical behaviors of a two-dimensional simplified Hodgkin–Huxley (H–H) model exposed to external electric fields are investigated through qualitative analysis and numerical simulation. A necessary and sufficient condition is proposed for the existence of the Hopf bifurcation. Saddle-node bifurcations and canards of the simplified model with the coefficients of different linear forms are also discussed. Finally, the bifurcation curves with the coefficients of different linear forms are shown. The numerical results demonstrate that some linear forms can retain the bifurcation characteristics of the original model, which is of great use to simplify the H–H model for the real-world applications. 相似文献
9.
This paper describes the design of guaranteed transient performance based attitude control for the near space vehicle(NSV)with control input saturation using the backstepping method.To improve the robust controllability of the NSV,the parameter adaptive method is used to tackle the integrated effect of unknown time-varying disturbance and control input saturation.Based on the backstepping technique and parameter estimated outputs,a robust attitude control scheme is proposed for the NSV with input saturation.A novel robust attitude control scheme is then proposed based on a prescribed performance bound(PPB)which characterizes the convergence rate and maximum overshoot of the attitude tracking error.The closed-loop system stability under both the developed robust attitude control schemes is proved using Lyapunov’s method and uniformly asymptotical convergence of all closed-loop signals is guaranteed.Finally,simulation results are given to show the effectiveness of both the proposed robust constrained attitude control schemes. 相似文献
10.
Summary It has been found that -dicarbonyl compounds such as 1-phenyl-butane-1,3-dione(benzoyl-acetone)and 4,4,4-trifluoro-phenylbutane-1,3-dione (benzoyl-trifluoroacetone) can effectively photostabilize photodegradation of polyisoprene in solutions containing protonic solvents (alcohols). The photostabilization mechanism is due to the photo-enolization reaction, during which absorbed UV radiation is consumed for the proceeding of this reaction. The photostabilization of formulations containing alcohol by -dicarbonyl compounds, has potential application in the protection of cosmetics against photoageing reaction. 相似文献