Scaling up the extrinsic curvature in gravitational initial data

Vacuum solutions to the Einstein equations can be viewed as the interplay between the geometry and the gravitational wave energy content. The constraints on initial data reflect this interaction. We assume we are looking at cosmological solutions to the Einstein equations so we assume that the 3-space is compact, without boundary. In this article we investigate, using both analytic and numerical techniques, what happens when the extrinsic curvature is increased while the background geometry is held fixed. This is equivalent to trying to magnify the local gravitational wave kinetic energy on an unchanged background. We find that the physical intrinsic curvature does not blow up. Rather the local volume of space expands to accommodate this attempt to increase the kinetic energy.Comment: 9 pages, 8 figure

Discussion on Urban Residential Building Energy Efficiency Design

With the rapid development of the country's overall per capita consumption level has been greatly improved, so as the development of urbanization, the demand for urban housing construction has greatly increased, and people's living standards but also pay more attention to improve energy saving urban housing, in order to ensure the health of people living environment, green, green. Furthermore, urban residential building energy saving marks the development of urban modernization, strictly follow the principle of sustainable development in our country. With the development of society, resources and energy consumption of large quantities of now, we do not just want to ensure the quality of people's living standards and even possible to reduce energy and resource consumption, so that energy-saving design of urban residential buildings became heavy in the weight. Therefore, this article on some of the problems of urban residential building energy efficiency design of the existence of and the factors affecting these issues briefly analyze and find appropriate solutions to ensure that the urban residential buildings not only meet the needs of people's lives but also to achieve energy saving and environmental protection role

A Rough-Set-basedClustering Algorithm for Multi-stream

AbstractThe paper propose a rough-set-based clustering algorithm for multiple data stream, which solve the problem that existing clustering algorithm for multiple data streams can not take into account conflicts between clustering quality and efficiency. Firstly, the algorithm calculates the distance between data stream to determine the initial equivalence relations, and calculates the similarity between the initial equivalence relation to determine the initial cluster. In the second place, the similarity between the initial clusters is used to merge the initial clusters. Finally, k-means clustering algorithm is called to dynamically adjust the clustering results, and then real-time clustering structure is obtained. In conclusion Experimental results demonstrated that the algorithm has higher efficiency and clustering quality

Processing techniques of point cloud data on small-sized objects with complex free-form surface

The scattered point cloud data, which comes from such small-sized objects with complex free-form surface as shelled shrimp, is processed as error points removing, points filtering, holes filling, clouds segmenting, etc. using CATIA V5 R20. The principle of data processing and skills utilized in the operation mentioned above apply also to the small-sized objects similar to the shelled shrimp in reverse engineering in other fields, such as optical components, irregular parts, ears, nose, etc