The work presented in this paper proposes a new technique called Edge Boundary Classification (EBC) for feature recognition from B-rep models. The technique uses the spatial addressability ...information of solid models that identifies the solid and void ‘sides’ of a boundary entity. Features can be interpreted from B-rep models based on the spatial properties of boundary entities. The purpose of feature recognition is to convert the geometric CAD data of a modeled part into a set of features suitable to support manufacturing activities such as in process planning system and inspection system. The application of the technique for cylindrical-based and conical-based features is presented. A case study is discussed and demonstrated to validate the proposed algorithms.
A new method was developed for the total reflection X-ray fluorescence (TXRF) determination of rhenium in molybdenum concentrates using gallium as internal standard. The samples were analyzed as ...slurries in TritonTM X-114. The experimental parameters, such as sample pretreatment and deposition, as well as slurry concentration, were optimized and matrix effects were investigated. Comparison with an independent method as well as the certified reference material CGL-202 were used for method validation. The method was applied to the determination of rhenium in a molybdenum concentrate from the "Elatsite-med" industrial plant located in Mirkovo, Bulgaria. The results obtained confirmed the suitability of TXRF for the fast and easy determination of rhenium in molybdenum concentrates.Key words: rhenium, molybdenum sulfide, TXRF analysis, gallium internal standard, slurry sampling
The Laser used correctly in the medical practice offers clear advantages compared with traditional therapies. The improvement and even the elimination of many significant skin lesions can be achieved ...with reduced risks to patients. However, it is important to keep security measures and understand the possible effects on an experimental model. The chick embryo is a good model to evaluate the direct effects of non-ionizing radiation for its easy handling and availability. The purpose of this communication is to show our histological findings in organs of the chick embryo with and without protective barrier to be subjected to radiation excimer. We used the following issuers: intense pulsed light (excimer Xe-Cl laser of 308 nm wavelength). It was irradiated embryos through an open window on eggshells. Aseptically the eggs were kept for 24 hours in an incubator. The protective barriers were used with and without colored glass, latex, cellophane, paper, polycarbonate of different colors and thicknesses. The most outstanding results, with no barrier and barriers with transparent and green were intense marked congestion in capillaries, edema and focus the necrosis. We concluded that the tissue changes observed are consistent with possible side effects of these radiations fototérmicos we warned about possible side effects when they are applied indiscriminately. We believe it is important to explore different means to safeguard the safety of operators and patients.
This paper present a new method for automatic form feature recognition from boundary representation of a solid model. The proposed method is called the edge boundary classification technique. This ...technique uses the geometry, topology, and spatial information of a solid model for feature recognition patterns. Some aspects of edge boundary classification are discussed for recognising non-intersecting and intersecting form features.
This study aimed to investigate the feasibility of low-dose computed tomographic (CT) urography with adaptive iterative dose reduction 3D (AIDR 3D).
Thirty patients underwent routine-dose CT scans ...with filtered back projection and low-dose CT scans with AIDR 3D in the excretory phase of CT urography. Visual evaluations were performed with respect to internal image noises, sharpness, streak artifacts, and diagnostic acceptability. Quantitative measures of the image noise and radiation dose were also obtained. All results were compared on the basis of body mass index (BMI).
At visual evaluations, streak artifacts in the urinary bladder were statistically weaker on low-dose CT than on routine-dose CT in the axial and coronal images (P < 0.001 and P = 0.01). There were no statistical differences between routine-dose CT and low-dose CT for other evaluation items in all structures. Image noise was lower on low-dose CT than on routine-dose CT in all structures (P < 0.001). The overall average dose reduction was 45.0% in all patients. The average dose reduction for the patients with a BMI of less than 20, 20 to 25, greater than 25 kg/m was 43.0%, 44.0%, and 49.6%, respectively.
Low-dose CT urography with AIDR 3D allows 45% reduction of radiation dose without degenerating of the image quality in the excretory phase independently to a BMI.
A new technique called edge boundary classification (EBC) for recognition of features from boundary representation (B-rep) solid model to support integrated manufacturing is presented. Features are ...interpreted from patterns formed by identifying the solid and void ‘sides’ of a boundary entity using the spatial addressability information of solid models. The application of the EBC technique for recognising simple and interacting cylindrical-based features is explained and discussed. The type of features experimented are through-hole, blind-hole, boss and internal undercut. The results obtained show that cylindrical-based features can easily be recognised using the EBC technique.
The success of future automated planning systems greatly depend on further advances in two areas: (a) enhanced product modelling systems capable of answering questions posed during the planning ...phase; and (b) techniques for representing and manipulating planning knowledge
The work reported in this paper, investigates the use of a feature-based approach for modelling engineering parts to support the product data requirements of an intelligent planning system, employing the frame-based and rule-based knowledge representation techniques from artificial intelligence research. The approach has been applied to the domain of rotational parts.
PDF
