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CAD System (cad + system)
Selected AbstractsNoninvasive quantitative assessment of oral tongue cancer by intraoral ultrasonographyHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 4 2007Masashi Yamane DDS Abstract Background. To assess tissue characterization of oral tongue cancer and prediction of subclinical cervical lymph node metastasis, we investigated whether intraoral ultrasonography could be used in conjunction with a computer-aided diagnosis (CAD) system. Methods. The study population comprised 109 patients with presurgical, clinical T1N0 or T2N0 oral tongue squamous cell carcinoma who underwent partial glossectomy. All the patients were examined by preoperative intraoral and postoperative exvivo ultrasonography. To evaluate the ultrasonic imagesquantitatively, ultrasonographic parameters from tumor contour features were computed by using the proposed CAD system. The imaging results were correlated with histopathologic findings. Results. Oral tongue cancer was clearly identified in all patients by intraoral ultrasonography. Ultrasonic images of oral tongue cancer reflected the histopathologic structures. Subclinical cervical lymph node metastasis was predicted by intraoral ultrasonography. In a logistic regression analysis using the proposed CAD system, the diagnostic sensitivity, specificity, and accuracy for prediction of subclinical lymph node metastasis were 87.2%, 84.3%, and 85.3%, respectively. Conclusions. Intraoral ultrasonography in conjunction with the proposed CAD system allows tissue characterization and prediction of subclinical cervical lymph node metastasis. © 2006 Wiley Periodicals, Inc. Head Neck, 2007. [source] Computer-aided diagnosis system for the detection of bronchiectasis in chest computed tomography imagesINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 4 2009D. Shiloah Elizabeth Abstract A computer-aided diagnosis (CAD) system has been developed for the detection of bronchiectasis from computed tomography (CT) images of chest. A set of CT images of the chest with known diagnosis were collected and these images were first denoised using Wiener filter. The lung tissue was then segmented using optimal thresholding. The Pathology Bearing Regions (PBRs) were then extracted by applying pixel-based segmentation. For each PBR, a gray level co-occurrence matrix (GLCM) was constructed. From the GLCM texture features were extracted and feature vectors were constructed. A probabilistic neural network (PNN) was constructed and trained using this set of feature vectors. The images together with the PBRs and the corresponding feature vector and diagnosis were stored in an image database. Rules for diagnosis and for determining the severity of the disease were generated by analyzing the images known to be affected by bronchiectasis. The rules were then validated by a human expert. The validated rules were stored in the Knowledge Base. When a physician gives a CT image to the CAD system, it first transforms the image into a set of feature vectors, one for each PBR in the image. It then performs the diagnosis using two techniques: PNN and mahalanobis distance measure. The final diagnosis and the severity of the disease are determined by correlating the diagnosis determined by both the techniques in consultation with the knowledge base. The system also retrieves similar cases from the database. Thus, this system would aid the physicians in diagnosing bronchiectasis. © 2009 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 19, 290,298, 2009 [source] Case study: A novel surface scanning systemJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 7 2005K. W. Tam This paper presents the design and development of a novel surface scanning system that employs an array of 144 equal spaced probing pins for capturing the surface coordinates of an object simultaneously. Operation of the system is computer driven. The captured surface data is saved in a point-cloud data file, which can be postprocessed by a CAD system to construct a surface model of the scanned object. The created CAD model can be used to facilitate the design and making of thermoforming moulds. The thermoforming moulds are to be used for forming plastic sheets for packaging consumer products for retail selling. A prototype of the system has been built. Test results demonstrate that the developed system can satisfy the technical and economical requirements of the packaging industry. © 2005 Wiley Periodicals, Inc. [source] CFD-based multi-objective optimization method for ship designINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 5 2006Yusuke Tahara Abstract This paper concerns development and demonstration of a computational fluid dynamics (CFD)-based multi-objective optimization method for ship design. Three main components of the method, i.e. computer-aided design (CAD), CFD, and optimizer modules are functionally independent and replaceable. The CAD used in the present study is NAPA system, which is one of the leading CAD systems in ship design. The CFD method is FLOWPACK version 2004d, a Reynolds-averaged Navier,Stokes (RaNS) solver developed by the present authors. The CFD method is implemented into a self-propulsion simulator, where the RaNS solver is coupled with a propeller-performance program. In addition, a maneuvering simulation model is developed and applied to predict ship maneuverability performance. Two nonlinear optimization algorithms are used in the present study, i.e. the successive quadratic programming and the multi-objective genetic algorithm, while the former is mainly used to verify the results from the latter. For demonstration of the present method, a multi-objective optimization problem is formulated where ship propulsion and maneuverability performances are considered. That is, the aim is to simultaneously minimize opposite hydrodynamic performances in design tradeoff. In the following, an overview of the present method is given, and results are presented and discussed for tanker stern optimization problem including detailed verification work on the present numerical schemes. Copyright © 2006 John Wiley & Sons, Ltd. [source] Features as an Abstraction for Designer Convenience in the Design of ShipsNAVAL ENGINEERS JOURNAL, Issue 4 2001Joshua D. Summers ABSTRACT This paper reports on a research effort involving design of a class of ships , nuclear submarines. It focuses on the use of features as a means of design abstraction, and it is found that a principal motivation for the use of features in this design environment is the convenience of the early stage submarine designer. To support this argument, a review of feature research is presented. Experiments in the development of feature catalogs are described, and implementation through two generations of feature-based submarine CAD systems are discussed. The architecture of the feature-based submarine CAD systems includes the use of Microsoft Foundation Classes (MFC), the ACIS geometric modeler, and user interfaces which store/recall hierarchical submarine feature information easily. Strong connections to object-oriented programming and object-oriented databases are recognized. Conclusions are drawn regarding the use of features for ship designer convenience and regarding support provided by hierarchical, parameterized features for other means of design automation. [source] | |||||||||||||