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91.
LIU JianCai XU JiaKai NING XinBao TIAN Run 《科学通报(英文版)》2007,52(17):2438-2442
The characterization of non-stationary signal requires joint time and frequency information. However, time and frequency are a pair of non-commuting variables that cannot constitute a joint probability density in the time-frequency plane. The time-frequency distributions have difficult interpretation problems arising from negative and complex values or spurious components. In this paper, we get time-frequency information from the marginal distributions in rotated directions in the time-frequency plane. The rigorous probability interpretation of the marginal distributions is without any ambiguities. This time-frequency transformation is similar to the computerized axial tomography (CT or CAT) and is applied to signal analysis and signal detection and reveals a lot of advantages especially in the signal detection of the low signal/noise (S/N). 相似文献
92.
Alexandra Sauer 《Systemic Practice and Action Research》2008,21(6):497-515
The participation of non-state actors in implementation processes is often understood as a means to increase compliance efficiency.
But the implementation of spatial policies frequently focuses on pre-established goals, processes and instruments and thus
renders difficult open discourse and shared decision-making. This paper introduces conflict pattern analysis (CPA) as a tool
that supports the analysis of the actual actor constellation in order to define efficient approaches that avoid common problems
of participatory processes. CPA is a semi-formalised method that helps to identify key-actors, their relations and interaction
amongst each other as well as their core beliefs, interests and resources. It aggregates this information to interaction patterns
that can be compared, classified and linked to different participatory methods on a theoretically informed basis. Particularly
on the local and regional level, this could be the first step for successful (participatory) implementation strategies. 相似文献
93.
S. K. MISHRA Shouyang WANG K. K. LAI 《系统科学与复杂性》2007,20(3):344-349
In this paper, we introduce a new class of generalized convex function, namely, a-pseudounivex function, by combining the concepts of pseudo-univex and α-invex functions. Further, we establish some relationships between vector variational-like inequality problems and vector optimization problems under the assumptions of α-pseudo-univex functions. Results obtained in this paper present a refinement and improvement of previously known results. 相似文献
94.
Hong Zhang Kui Zhang Ying Mu Ning Yao Robert J. Sclabassi Mingui Sun 《自然科学进展(英文版)》2008,18(12):1507-1512
Image-based gait analysis as a means of biometric identification has attracted much research attention. Most of the existing methods focus on human identification, posture analysis and movement tracking. There have been few investigations on measuring the carried load based on the carrier's gait characteristics by automatic image processing. Nevertheless, this measurement is very useful in a number of applications, such as the study of the carried load on the postural development of children and adolescence. In this paper, we investigate how to automatically estimate the carried weight from a sequence of images. We present a method to extract human gait silhouette based on an observation that humans tend to minimize the energy during motion. We compute several angles of body leaning and determine the relationship of the carried weight, the leaning angles and the centroid location according to a human kinetic study. Our weight determination method has been verified successfully by experiments. 相似文献
95.
A theoretical model for mid-and low-latitude ionospheric electric fields in realistic geomagnetic fields 总被引:1,自引:1,他引:0
The geomagnetic fields, which play important roles in the ionospheric dynamo, can greatly affect the global distribution of ionospheric electric fields, currents and other ionospheric electrodynamics phenomena. In the study of ionospheric electrodynamics phenomena, such as the longitudinal variations of ionospheric electric fields, the non-dipolar component of the geomagnetic fields must be taken into account. In this paper, we deduce a theoretical electric field model for ionospheric dynamo at mid- and low-latitude which adopt a modified magnetic apex coordinates system. In the new electric field model, the geomagnetic fields can be calculated from either the IGRF model or the dipole field model, and the neutral winds and conductivities are calculated based on empirical models. Then the dynamo equation for the electric potential is finally solved in terms of the line-by-line iteration method, and the ionospheric electric fields and currents are derived from the calculated potential. Our model can reproduce the main features of the ionospheric electrodynamics processes, so it will be a useful tool for the investigation of the upper atmosphere and ionosphere. 相似文献
96.
孙明保 《湖南理工学院学报:自然科学版》1995,(1)
M.S.Klamkin在文[1]中获得了E~n中之Euler不等式,本文给出了E~n中Euler不等式的改进。 相似文献
97.
孙进生 《河北理工学院学报》1996,18(1):30-34
对影响寻呼台正常运行的几个主要问题,从无线发射系统和计算机网络两个方面进行了探讨和分析,并介绍了相应的解决方法。 相似文献
98.
本文介绍了作者开发的群速度和相速度微机模拟软件的程序设计和实现.该软件做为演示实验已经取得了良好的效果. 相似文献
99.
研究了金属间化合物快速凝固薄带的成型过程和影响薄带质量的工艺参数。提出了熔体在喷嘴处进行层流流动的经验关系式,给出了金属间化合物快速凝固薄带制备的最佳工艺参数。 相似文献
100.
综合分析生物电化学、功能高分子修饰电极及现代分析仪器几个领域的发展现状及应用前景。 相似文献