A fast experimental beam hardening correction method for accurate bone mineral measurements in 3D μCT imaging system

Bone mineral density plays an important role in the determination of bone strength and fracture risks. Consequently, it is very important to obtain accurate bone mineral density measurements. The microcomputerized tomography system provides 3D information about the architectural properties of bone. Quantitative analysis accuracy is decreased by the presence of artefacts in the reconstructed images, mainly due to beam hardening artefacts (such as cupping artefacts). In this paper, we introduced a new beam hardening correction method based on a postreconstruction technique performed with the use of off‐line water and bone linearization curves experimentally calculated aiming to take into account the nonhomogeneity in the scanned animal. In order to evaluate the mass correction rate, calibration line has been carried out to convert the reconstructed linear attenuation coefficient into bone masses. The presented correction method was then applied on a multimaterial cylindrical phantom and on mouse skeleton images. Mass correction rate up to 18% between uncorrected and corrected images were obtained as well as a remarkable improvement of a calculated mouse femur mass has been noticed. Results were also compared to those obtained when using the simple water linearization technique which does not take into account the nonhomogeneity in the object.     

A COMPARISON OF THREE INSTRUMENTAL TESTS FOR PREDICTING SENSORY TEXTURE PROFILES OF CHEESE

Multivariate analysis techniques were used to seek correlations between texture sensory attributes assessed by a trained professional panel and instrumental measurements (compression, puncture and penetration) carried out on various types of cheeses. Twenty-nine cheeses were assessed by the panel and instruments. Correlation was sought using Partial Least Squares regression. Hardness (R=0.87), springiness (R=0.98) and cohesiveness of mass (R=0.89) were best predicted by instrumental data from a cone penetration test. The prediction of cohesiveness was acceptable using any of the three instrumental tests performed (0.76相似文献   

Artificial Intelligence Software Engineering in Building Engineering

This article provides a review of two main research projects carried out at the French Scientific and Technical Center for Building (CSTB) in the area of artificial intelligence applied to building engineering. We first describe the software engineering techniques used to develop the computer environments. Then we present the architecture of an advanced multiservice computer system offering capabilities comprising retrieval facilities, hypertext editing of documents (e.g., unified codes of practice, regulations), object-oriented database management, and multifunctional expert systems. Finally we discuss a major multiactor computeraided design project aiming to provide a framework able to combine the sundry contributions of the various actors involved in the building design process. The expected results of such projects are a panel of complementary capabilities either aiming at satisfying multiservice requirements for an isolated designer or at providing a single but cooperative and computer-assisted process to different actors. Of course, merging the respective capabilities of these tools is a very promising perspective.     

INTEGRATED ACCESS TO INFORMATION SYSTEMS

The French Scientific and Technical Center for Building (CSTB) is involved in a very large number of programs, covering a wide range of scopes in the area of building, including technical, legal, social, and economic topics. The actions carried out encompass scientific research or technical missions, engineering, writing regulations, or state-of-the-art documents, such as unified codes of practice or assessment of the social impact of new technologies, and the need to facilitate access to this huge amount of data has become a considerable challenge. Information in such a case is a very generic term covering a vague understanding in that it can include basic data representing a primary corpus or, at the other end of the scale, sophisticated services offered by experts able to solve complex problems. Customers for such information have very different needs but agree on the necessity to facilitate access to the relevant data and to various high-value services accounted for by computer systems. As the semantic level of the services differs considerably, the need became apparent to merge different tools within an integrated software environment to satisfy the previous objective. The main components to be assembled are retrieval systems to locate the relevant data, object-oriented databases to offer a reusable storage model, hypertext and hyperobject systems to browse the content of hypermedia entities, and multifunctional expert systems to provide sophisticated computer systems with an adaptable entry and behavior.