with the rapid growth of indoor wireless communication systems, the need to accurately model radio wave propagation inside the building environments has increased. many site-specific methods have been proposed for modeling indoor radio channels. among these methods, the ray tracing algorithm and the finite-difference time domain (fdtd) method are the most popular ones. the ray tracing approach ...

Common three-dimensional (3D) modeling software mainly uses sequence modeling method based on feature tree structure. This kind of parametric modeling is achieved by using dimensional constraints. However, re-editing of any historical features will cause regeneration of the subsequent features, thus resulting in substantial waste of computer resources and time. Compared with sequence modeling t...

Architecture and engineering firms use building information management BIM software applications increasingly in the design process; similarly, building owners create BIM models for existing facilities both for internal use and to aid future tenants, facilities managers, and designers in planning for maintenance programs, restoration, or renovation. As for other design and engineering disciplin...

This paper presents the surface-based factorization method to recover three-dimensional (3-D) structure, i.e., the 3-D shape and 3-D motion, of a rigid object from a two-dimensional (2-D) video sequence. The main ingredients of our approach are as follows: 1) we describe the unknown shape of the 3-D rigid object by polynomial patches; 2) projections of these patches in the image plane move acco...

in this paper, fourteen mt stations along a profile perpendicular to the main geological structure were used in order to identify the geology of sabalan geothermal field including the extension of the surface cap-rock and clay-cap layers. the mt data collected between 1-8192 hz is of useful quality and provides good control on the surface layers in many areas. it means that reliable modeling sh...

Background: Lipophosphoglycan 3 (LPG3) is required for the LPG assembly, a well known virulent molecule. In this study, the LPG3 gene of the lizard and mammalian Leishmania species were cloned and sequenced. A three-dimensional structure (3D) for the target sequence was also predicted by comparative (homology) modeling. Materials and Methods: An optimization PCR amplification was performed o...

Abnormal loads due to natural events, implementation errors and some other issues can lead to occurrence of progressive collapse in structures. Most of the past researches consist of 2- Dimensional (2D) models of steel frames without consideration of the floor system effects, which reduces the accuracy of the modeling. While employing a 3-Dimensional (3D) model and modeling the concrete slab sy...

Dimensional modeling is a common modeling technique in data warehousing. It reflects a simple logical view of a data warehouse system. It can be easily mapped to a physical design. Traditional dimensional modeling is data-oriented and semantically informal. From a software engineering perspective, the informal notations and data-oriented feature are insufficient to tackle the complexity of larg...

system dynamics is a strategic approach for modeling complex systems and analyzing their behavior. dynamic behavior in entrepreneurial system can be modeled using system dynamics approach and dynamic hypotheses about the system`s behavior can be proposed and tested using simulation and computer aided tools. however, as the review of literature shows, studies which link system dynamics modeling ...

Large database schemata can be drastically simplified if techniques of modular and structural modeling are used. Applications and thus schemata have an inner meta-structure. The explicit treatment of the inner structuring may be used during development of large database schemata and may ease the development to a large extent. It is surprising that dimensions and internal separations have not be...