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81.
江红  江东 《信息技术》2002,(3):34-34,37
PowerPoint2000是Microsoft公司办公自动化软件Office2000的重要构件之一。其自身具有强大的处理功能,尤其是PowerPoint2000所提供的基本动画效果,更是给演示文稿增添了很多色彩。如果能将这些基本动画效果巧妙地组合在一起,就会创作出更富感染力的作品。就创作中的技巧并结合应用举例分析如下。相信人们可以利用这些设计思想,创作出更加精彩的作品。  相似文献   
82.
FW调剖技术及应用   总被引:1,自引:0,他引:1  
应用FW调剖技术有针对性地对 119口非钻停井区注水井采取了 4种精细调剖方案 ,对比了化学浅调剖应用前后注水井层间矛盾的缓解 ,纵向上吸水剖面的改善 ,注水量和吸水指数的变化及渗流能力的变化。结果表明 ,注水井化学浅调剖后 ,井区的连通油井明显受效 ,获得较高的增油量 ,水驱的开发效果得到改善。化学浅调剖可以有效地封堵高渗透层 ,扩大低渗透层注入水的波及体积 ,减缓注水井层间矛盾 ,实现了对注水井吸水剖面的有效调整 ,这对深化注水结构调整、挖掘各类油层潜力、提高储量动用程度有显著的效果。  相似文献   
83.
1Introduction Harmfulbacteriaexistanywhereintheworldsuchas soil,air,water,surfacesofobjectsandourskins,etc.Thenumberofbacteriumisenormous,withmanydiffer entspecies.Theyhavethreatenedthehealthofhuman beingsseriously.Withthedevelopmentofeconomyand environme…  相似文献   
84.
针对武钢热轧厂层流冷却系统能耗高,水压不稳,系统反应慢,供水泵工作效率低等缺陷,进行系统改造。提高了系统的控制精度和产品质量,节能降耗取得了明显的效果。  相似文献   
85.
The authors studied the role of gamma-aminobutyric acid (GABA) in 2 types of forgetting of fear in the developing rat. One type of forgetting studied was that observed after an intermediate retention interval (the "Kamin effect"); the other type studied was that observed after a longer interval (infantile amnesia). Rats were given pairings of an auditory conditioned stimulus with shock, and learned fear was assessed by freezing. Forgetting at an intermediate retention interval (1 hr) was not alleviated by the GABAA receptor partial inverse agonist FG7142 (0, 1, 5, or 10 mg/kg), whereas forgetting at a longer retention interval (48 hr) was alleviated. These results suggest that in the developing rat, forgetting observed at different retention intervals is mediated by different physiological mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
The effect of ductile crack growth on the near tip stress field in two different specimen geometries has been investigated. For homogeneous specimens it is observed that the peak stress level increases with ductile crack growth. The effect is most pronounced up to about 1 mm of crack growth. For low and intermediate hardening there is a significant effect of specimen size on the stress level. In case of mismatch in yield stress, the simulations show that the increase in stress level in the material with the lower yield stress is of a similar magnitude as is the case for stationary cracks. In case of ductile crack growth deviation from the original crack plane occurs, the highest stresses are still found close to the interface, and not in front of the current crack tip.  相似文献   
87.
A model for propagating deformation bands is developed, based on a mechanical equation of state and on evolution equations for the structure parameters. It is shown that, contrary to normal deformation, it is necessary to discriminate between global parameters which depend solely on time elapsed and local parameters which are functions of the strain history. Correspondingly, two sets of equations are presented, one describing the development of the global parameters in the course of time, the other giving the evolution of the local state parameters in the course of deformation, i.e. as a function of strain. Measurable quantities derived from the first set are the load serrations and the band velocity, while the second set yields the flow stress and the strain profile of the propagating band.  相似文献   
88.
The dynamics of a thin liquid film falling down a uniformly heated wall is studied. The model introduced by Kalliadasis et al. [J. Fluid Mech. 475 (2003) 377] for the same problem is revisited and its deficiencies, namely the prediction of a critical Reynolds number with 20% error, cured. For the energy equation a high-order Galerkin projection in terms of polynomial test functions is developed. It is shown that not only does this more refined formulation correct the critical Reynolds number, but it also gives, with an appropriate expansion close to criticality, the long-wave theory. Bifurcation diagrams for permanent solitary waves are constructed and compared with the solution branches obtained from different models. It is shown that, in all cases, the long-wave theory exhibits limit points and branch multiplicity, while the other models predict the continuing existence of solitary waves. Time-dependent computations show that the free surface and interfacial temperature approach a train of coherent structures that resemble the infinite-domain stationary solitary pulses.  相似文献   
89.
Corner detection is a low-level feature detection operator that is of great use in image processing applications, for example, optical flow and structure from motion by image correspondence. The detection of corners is a computationally intensive operation. Past implementations of corner detection techniques have been restricted to software. In this paper we propose an efficient very large-scale integration (VLSI) architecture for detection of corners in images. The corner detection technique is based on the half-edge concept and the first directional derivative of Gaussian. Apart from the location of the corner points, the algorithm also computes the corner orientation and the corner angle and outputs the edge map of the image. The symmetrical properties of the masks are utilized to reduce the number of convolutions effectively, from eight to two. Therefore, the number of multiplications required per pixel is reduced from 1800 to 392. Thus, the proposed architecture yields a speed-up factor of 4.6 over conventional convolution architectures. The architecture uses the principles of pipelining and parallelism and can be implemented in VLSI.  相似文献   
90.
钟晓瑜 《钻采工艺》2003,26(Z1):57-59
介绍了池27井实施机抽排水工艺取得累计排水13 334.4m3的明显效果.分析了五次检泵的原因.提出了对池27井机抽排水的四点认识.  相似文献   
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