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21.
Consistency constraints and 3D building reconstruction 总被引:2,自引:0,他引:2
Virtual architectural (indoor) scenes are often modeled in 3D for various types of simulation systems. For instance, some authors propose methods dedicated to lighting, heat transfer, acoustic or radio-wave propagation simulations. These methods rely in most cases on a volumetric representation of the environment, with adjacency and incidence relationships. Unfortunately, many buildings data are only given by 2D plans and the 3D needs varies from one application to another. To face these problems, we propose a formal representation of consistency constraints dedicated to building interiors and associated with a topological model. We show that such a representation can be used for: (i) reconstructing 3D models from 2D architectural plans (ii) detecting automatically geometrical, topological and semantical inconsistencies (iii) designing automatic and semi-automatic operations to correct and enrich a 2D plan. All our constraints are homogeneously defined in 2D and 3D, implemented with generalized maps and used in modeling operations. We explain how this model can be successfully used for lighting and radio-wave propagation simulations. 相似文献
22.
María Cristina Riff Xavier Bonnaire Bertrand Neveu 《Engineering Applications of Artificial Intelligence》2009,22(4-5):823-827
In this paper, we present a review of the recent approaches proposed in the literature for strip-packing problems. Many of them have been concurrently published, given some similar results for the same set of benchmarks. Due to the quantity of published papers, it is difficult to ascertain the level of current research in this area. 相似文献
23.
Bertrand Baud-Lavigne Samuel Bassetto Bruno Agard 《Journal of Intelligent Manufacturing》2016,27(4):741-749
This paper proposes a method for finding a robust solution to the problem of joint product family and supply chain design. Optimizing product design and the supply chain network at the same time brings substantial benefits. However, this approach involves decisions that can generate uncertainties in the long term. The challenge is to come up with a method that can adapt to most possible environments without straying too far from the optimal solution. Our approach is based on the generation of scenarios that correspond to combinations of uncertain parameters within the model. The performance of designs resulting from these scenario optimizations are compared to the performance of each of the other design scenarios, based on their probability of occurrence. The proposed methodology will allow practitioners to choose a suitable design, from the most profitable to the most reliable. 相似文献
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This paper describes a parameterized distributed algorithm applicable to any directed graph topology. The function parameter
of our algorithm is instantiated to produce distributed algorithms for both fundamental and high level applications, such
as shortest path calculus and depth-first-search tree construction. Due to fault resilience properties of our algorithm, the
resulting protocols are self-stabilizing at no additional cost. Self-stabilizing protocols can resist transient failures and
guarantee system recovery in a finite time. Since the condition on the function parameter (being a strictly idempotent r-operator) permits a broad range of applications to be implemented, the solution presented in our paper can be useful for
a large class of distributed systems.
Received: August 1999 / Accepted: January 2001 相似文献
27.
R. Terki G. Bertrand H. Aourag C. Coddet 《Materials Science in Semiconductor Processing》2006,9(6):1006
The structural and electronic properties of ZrO2 polymorphs were investigated using density functional theory (DFT). The Kohn–Sham equations were solved by applying the full-potential linearized augmented plane wave (FP-LAPW) method. We used the generalized gradient approximation (GGA) in the Perdew–Wang formalism to the exchange and correlation energy functional. The ground state properties such as lattice parameter, transition pressures, bulk modulus and its pressure derivative as well as the structural phase stability were calculated. The results were compared with previous calculations and experimental data when available. The FP-LAPW method correctly orders the zero temperature energies of all zirconia polymorphs. We have also studied the effect of distortion from the cubic to the tetragonal structure on the basis of charge density calculations. On the other hand, band structure and density of states (DOS), which allow us to discuss the features of orbital mixing, are also given. Our results suggest that the cotunnite structure should be better than the other zirconia phases as gate dielectric material. 相似文献
28.
Raymond Rosenbloom Igor Gavrish Anna E. Tseng Kerstin Seidel Shivraj M. Yabaji Hans P. Gertje Bertrand R. Huber Igor Kramnik Nicholas A. Crossland 《International journal of molecular sciences》2022,23(11)
Pulmonary infections caused by the group of nontuberculosis mycobacteria (NTM), Mycobacterium avium complex (MAC), are a growing public health concern with incidence and mortality steadily increasing globally. Granulomatous inflammation is the hallmark of MAC lung infection, yet reliable correlates of disease progression, susceptibility, and resolution are poorly defined. Unlike widely used inbred mouse strains, mice that carry the mutant allele at the genetic locus sst1 develop human-like pulmonary tuberculosis featuring well-organized caseating granulomas. We characterized pulmonary temporospatial outcomes of intranasal and left intrabronchial M. avium spp. hominissuis (M.av) induced pneumonia in B6.Sst1S mice, which carries the sst1 mutant allele. We utilized traditional semi-quantitative histomorphological evaluation, in combination with fluorescent multiplex immunohistochemistry (fmIHC), whole slide imaging, and quantitative digital image analysis. Followingintrabronchiolar infection with the laboratory M.av strain 101, the B6.Sst1S pulmonary lesions progressed 12–16 weeks post infection (wpi), with plateauing and/or resolving disease by 21 wpi. Caseating granulomas were not observed during the study. Disease progression from 12–16 wpi was associated with increased acid-fast bacilli, area of secondary granulomatous pneumonia lesions, and Arg1+ and double positive iNOS+/Arg1+ macrophages. Compared to B6 WT, at 16 wpi, B6.Sst1S lungs exhibited an increased area of acid-fast bacilli, larger secondary lesions with greater Arg1+ and double positive iNOS+/Arg1+ macrophages, and reduced T cell density. This morphomolecular analysis of histologic correlates of disease progression in B6.Sst1S could serve as a platform for assessment of medical countermeasures against NTM infection. 相似文献
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This personal account summarizes our work, beginning with the discovery of the first stable carbene in 1988 up until the recent isolation of mesoionic carbenes. It explains why we have moved our focus from acyclic to cyclic carbenes, and shows that these stable species are not limited to the role of ligand for transition metals, but that they are also powerful agents for the activation of small molecules, and for the stabilization of highly reactive diamagnetic and paramagnetic species. 相似文献