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In this study, the substructure formation in a multi-pass rolled aluminium single crystal {001}<110> was investigated by the crystal plasticity finite element model, and the predations were validated by experimental observations at both macro- and micro-scale. A finite element model for multi-pass rolling was developed to follow the real experimental rolling scheme, by which the through-thickness macroscopic subdivision was successfully predicted up to a 90 % reduction. The macro-subdivision was featured by forming matrix bands through the thickness, and the deformation behaviours, in terms of slip activity, shear strain and crystal rotation, alternated between matrix bands. The development of matrix bands, stability of crystal orientations, and correlation between slip activity, shear strain and crystal rotation have been investigated. Another modelling method, Submodel, was used to exceedingly increase the mesh resolution in smaller regions of interest, and the experimentally observed microstructure, i.e., micro-subdivision was explicitly and spatially revealed. Similar predictions were obtained in Submodels with different element sizes, which proves the feasibility of this method in predicting microstructure formation. It was found that the substructure formation by varying slip activity and crystal rotation between domains is energy favourable. The procedure of substructure formation was explained based on the predictions, three types of substructure have been identified, and the substructure formation was discussed. [ABSTRACT FROM AUTHOR]

When division is performed by a power series implementation with additions, subtractions, digit shifts, and multiplications the convergence rate of the power series is important in practical application Particularly if the rate of the power series is close to one, the convergence is slow and therefore a special method to accelerate the convergence is needed. Without such an acceleration, the power series implementation is less attractive. An acceleration method is proposed for the slow convergence rate. First, the worst case convergence rate of the power series is determined for a given appropriate acceleration factor. Next, a simple way to choose the appropriate acceleration factor is presented. [ABSTRACT FROM AUTHOR]

Analysis of nonlinear dynamical systems including finding equilibrium states and stability boundaries often leads to a problem of finding zeros of vector functions. However, finding all the zeros of a set of vector functions in the domain of interest is quite a challenging task. This paper proposes a zero finding algorithm that combines the cell mapping methods and the subdivision techniques. Both the simple cell mapping (SCM) and generalized cell mapping (GCM) methods are used to identify a covering set of zeros. The subdivision technique is applied to enhance the solution resolution. The parallel implementation of the proposed method is discussed extensively. Several examples are presented to demonstrate the application and effectiveness of the proposed method. We then extend the study of finding zeros to the problem of finding stability boundaries of potential fields. Examples of two and three dimensional potential fields are studied. In addition to the effectiveness in finding the stability boundaries, the proposed method can handle several millions of cells in just a few seconds with the help of parallel computing in graphics processing units (GPUs). [ABSTRACT FROM AUTHOR]

Rural residential development in the Rocky Mountain West of North America is resulting in increased conflict between ungulate habitat and infrastructure. Subdivisions, houses, and roads affect ungulates both behaviorally and demographically and reduce management options available to agencies. These habitat alterations need to be addressed if wildlife species are to coexist with humans. We reviewed literature (using 7 search engines and 16 key words) on the effects of land-use change (especially residential development) on elk ( Cervus canadensis), mule deer ( Odocoileus hemionus), white-tailed deer ( O. virginianus), American pronghorn ( Antilocapra americana), and bighorn sheep ( Ovis canadensis). Approximately 80 studies were directly related to the effects of human development on ungulates; however, only 25 specifically examined residential development and its influences on the focal species. Studies varied in methodology (i.e., aerial and ground surveys, pellet counts, movement rates) and analyses. The literature suggests most ungulates exhibit short-term behavioral reactions to human disturbance. However, few studies link these responses to population-level consequences or test the cumulative impact that multiple developments and development types (i.e., roads, housing, industrial development) have on seasonal habitat use and migratory behavior. Short-term and small-scale observational studies have articulated the conflict between humans and ungulates on shared habitat. Those studies need to be followed with well-designed experiments and large-scale multi-jurisdictional projects so that managers and planners can make more credible recommendations to direct future exurban development that benefits wildlife and humans. © 2012 The Wildlife Society. [ABSTRACT FROM AUTHOR]

In this paper, a power-area efficient geometry engine (GE) using a low-complexity three-level subdivision algorithm is presented. The proposed subdivision algorithm and architecture is capable of providing low complexity, high power-area efficiency, scalable and near-Phong shading quality. The forward difference, edge function recovery, dual space subdivision, triangle filtering, and triangle setup coefficient sharing schemes are employed to alleviate the redundant computation for the proposed algorithm. According to the low-complexity subdivision algorithm, one reconfigurable datapath is proposed to save the area since the same set of processing elements (PE) is reused for different operations of GE. Compared with the conventional subdivision algorithm, the proposed subdivision algorithm reduces the number of memory/register accesses for subdivision by 40% and 60.32% for level-1 and level-2 subdivision, respectively. In terms of the number of multiplications for transforms, the reduction can be attained by 27.5% and 60.27% for level-1 and level-2 subdivision, respectively. From the implementation results, the proposed GE can achieve the power-area efficiency of 518.8 Kvertices/(s\bulletmW\bulletmm^2) for level-1 subdivision. [ABSTRACT FROM PUBLISHER]

Abstract: A deformation technique is a method to deform any part of, or an entire object, into a desired shape. Existing deformation methods take a lot of computational cost to represent smoothness correctly due to the constraints caused by differential coefficients of high degree. Thus, it is very difficult to find a general solution. In this paper we propose a LSM (layered subdivision method) that integrates a controlling mechanism, surface deformation, and mesh refinement processing 3D modeling and free-form deformable object matching. The proposed method is considerably more efficient and robust when compared to the existing method of free-form surface, because of the computation of the reference points of deformation edge using geometry of free-form surface. This approach can be applied to automatic inspection of NURBS models and object recognition. [Copyright &y& Elsevier]

A hierarchical volume rendering algorithm is presented. Volume emissions in optically thin media are considered. A sparse hierarchical wavelet-based representation of the directional volume emission rate function is constructed top-down and then projected onto the image plane. This makes the algorithm fast, since the number of operations is proportional to the number of coefficients in the representation. Also, the sparsity minimizes the algorithm’s memory requirement. The representation is constructed using conservative subdivision, making the projection onto a lower-dimensional representation trivial. The error is controlled by a threshold parameter, allowing a direct trade-off between speed and accuracy. The algorithm is especially well suited when the directional volume emission rate is computationally expensive to evaluate, since the sparse representation minimizes the number of function evaluations for rendering a volume with a specified accuracy. Since a sparse oct-tree is constructed for a specific view point the method is best suited to situations where an image is to be generated from one view point. [Copyright &y& Elsevier]

The more the rate of sub-division of the grid into subareas is high, the more the Maxwell's sub-areas method of studying the current field generated by a grounding grid is accurate. In this paper the authors suggest a fuzzy approach applied to a horizontal cylindrical electrode which allows them to determine in advance the errors due to the different rates of subdivision. [ABSTRACT FROM AUTHOR]

The article presents information on the housing market boom in Phoenix, Arizona, in 2012. It is stated that U.S. Housing prices in metropolitan Phoenix increased by 22.9 percent in 2012, which is the highest in the nation. It is mentioned that Pulte Homes Inc. is the largest homebuilder in the U.S. by market value, and the company earned a revenue of 4.8 billion dollars in 2012, with a profit of 206 million dollars.