
Applied Ergonomics
One of the orientations of the tool-making industry is towards shortening the time from enquiry to the supply of tools. The tool-making shops must prepare within the shortest possible time an offer for the manufacturer of the tool based on the enquiry in the form of the CAD-model of the final product. For preparation of a proper offer, the values of certain technological features occurring in the manufacture of the tool are needed. Most frequently the tool manufacturer is interested in total cost for manufacture of the tool. Because of lack of time for making a detailed analysis the total costs of tool manufacture are predicted by the expert on the basis of the experience gathered during several years of work in this area. In our work, we conceived an intelligent system for predicting of total cost of the tool manufacture. We limited ourselves to tools for manufacture of sheet metal products by stamping; the system is based on the concept of case-based reasoning. On the basis of target and source cases, the system prepares the prediction of costs. The target case is the CAD-model in whose costs we are interested, whereas the source cases are the CAD-model of products, for which the tools had already been made, and the relevant total costs are known. The system first abstracts from CAD-models the geometrical features, and then it calculates the similarities between the source cases and target case. Then the most similar cases are used for preparation of prediction by genetic programming method. The genetic programming method provides the model connecting the individual geometrical features with total costs searched for. In the experimental work, we made a system adapted for predicting of tool costs used for tool manufacture on the basis of a theoretic model. The results show that the quality of predictions made by the intelligent system is comparable to the quality assured by the experienced expert.
Article Outline
1. Introduction
2. Present situation
2.1. Tool manufacturing costs
2.2. Cost prediction methods
3. Model of intelligent system for prediction of tool manufacturing costs
3.1. Case-based reasoning
3.2. Description of model
3.3. Abstraction of CAD-model
3.4. Similarities of cases
3.5. Selection of the most similar source cases
3.6. Genetic programming
3.7. Preparation and use of formula
4. Example and results
5. Conclusion
References
Investigating Knowledge Management practices in software development organisations – An Australian experience Original Research Article
Information and Software Technology
Prediction of total manufacturing costs for stamping tool on the basis of CAD-model of finished product Original Research Article
Journal of Materials Processing Technology
This paper provides an overview of opportunities and challenges for expert coordination, knowledge sharing, and task performance using advanced information and communication technologies. Evolving in part from [Hendrick, H., 1991. Ergonomics in organizational design and management. Ergonomics 34(6), 743–756] discussion of macroergonomics, this paper describes the author's framework for systems engineering analysis of information flow and performance at team and organizational units of analysis. Work in the author's research lab has focused on several aspects of information technology use and team interactions to support shared understandings, task demands, and effective responses in responses to events. Multiple empirical studies are summarized describing evaluations of technology use, task cycles and expert knowledge coordination in several settings, including aerospace, healthcare, and project management.
Article Outline
1. Introduction
2. Information and communication technologies as organization–machine interface support
3. Analysis tools to examine expert performance constraints and goals
4. Time and delay in information flow and knowledge synchronization
5. Extending from individuals to teams and organizations
6. Components of delay in knowledge sharing and event response
6.1. Types of flow constraints and limitations
6.2. Sources of delay
7. Empirical examples of delay, event dynamics and response in distributed teams
7.1. Study 1
7.2. Study 2
7.3. Study 3
7.4. Study 4
7.5. Study 5
8. Discussion and conclusion
Acknowledgements
References
In order to meet the requirements of customized artificial joint design, and to reduce the production cycle and cost, we present a method to generate the complex surface of an artificial knee joint by co-ordinate measuring machine (CMM) from the normative prosthesis, and form the model data base. First, this paper describes how to plan the measure method to get the better data points and how to deal with the point cloud data. Then, the free-form surfaces are constructed from the point cloud data using the reverse engineering software—Surfacer. Lastly, the solid CAD model of the artificial knee joint is created from the surfaces by extension, intersection and so on. These models formed the data base of the prosthesis, in which we can select a suitable kind of artificial knee joint model to customize for the patient. That is, we only need to change the local data of the corresponding CAD model to meet the different requirements of the patient.
Article Outline
1. Introduction
2. Materials and methods
2.1. Digitization from the surface
2.2. Preprocessing of the point clouds
2.3. Surface fitting
2.3.1. Point processing
2.3.2. Curve processing
2.3.3. Surface processing
3. Results
4. Discussion
Acknowledgements
References
Medical Image Analysis
Volume 14, Issue 3, June 2010, Pages 390-406
| doi:10.1016/j.media.2010.02.004 | How to Cite or Link Using DOI Copyright © 2010 Elsevier B.V. All rights reserved. | Cited By in Scopus (0) |
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Temesguen Messaya, , , Russell C. Hardiea, and Steven K. Rogersb,
a Department of Electrical and Computer Engineering, University of Dayton, 300 College Park, Dayton, OH 45469-0232, United States
b Air Force Research Laboratory, AFRL/RY Wright Patterson AFB, OH 45433, United States
Received 7 November 2008;
revised 1 February 2010;
accepted 3 February 2010.
Available online 19 February 2010.
Abstract
Early detection of lung nodules is extremely important for the diagnosis and clinical management of lung cancer. In this paper, a novel computer aided detection (CAD) system for the detection of pulmonary nodules in thoracic computed tomography (CT) imagery is presented. The paper describes the architecture of the CAD system and assesses its performance on a publicly available database to serve as a benchmark for future research efforts. Training and tuning of all modules in our CAD system is done using a separate and independent dataset provided courtesy of the University of Texas Medical Branch (UTMB). The publicly available testing dataset is that created by the Lung Image Database Consortium (LIDC). The LIDC data used here is comprised of 84 CT scans containing 143 nodules ranging from 3 to 30 mm in effective size that are manually segmented at least by one of the four radiologists. The CAD system uses a fully automated lung segmentation algorithm to define the boundaries of the lung regions. It combines intensity thresholding with morphological processing to detect and segment nodule candidates simultaneously. A set of 245 features is computed for each segmented nodule candidate. A sequential forward selection process is used to determine the optimum subset of features for two distinct classifiers, a Fisher Linear Discriminant (FLD) classifier and a quadratic classifier. A performance comparison between the two classifiers is presented, and based on this, the FLD classifier is selected for the CAD system. With an average of 517.5 nodule candidates per case/scan (517.5 ± 72.9), the proposed front-end detector/segmentor is able to detect 92.8% of all the nodules in the LIDC/testing dataset (based on merged ground truth). The mean overlap between the nodule regions delineated by three or more radiologists and the ones segmented by the proposed segmentation algorithm is approximately 63%. Overall, with a specificity of 3 false positives (FPs) per case/patient on average, the CAD system is able to correctly identify 80.4% of the nodules (115/143) using 40 selected features. A 7-fold cross-validation performance analysis using the LIDC database only shows CAD sensitivity of 82.66% with an average of 3 FPs per CT scan/case.
Keywords: Computer aided detection (CAD); Lung nodule; Computed tomography (CT); LIDC; ANODE09
Article Outline
1.
Introduction
2.
Materials
2.1. LIDC
2.2. UTMB
3.
CAD system
3.1. Preprocessor
3.1.1. Orienting and down-sampling
3.1.2. Local contrast enhancement
3.1.3. 3-D lung segmentation
3.2. 3-D nodule candidate detection and segmentation
3.3. 3-D nodule candidate features
3.4. Feature selection and classifiers
4.
Experimental results
4.1. Labeling and scoring
4.2. Nodule candidate detection and segmentation performance
4.3. Overall system performance
4.4. Performance comparison
5.
Conclusion
Acknowledgements
References
Research highlights
► Method and standard for the processing of Engineering Changes in the automotive supply chain. ► Model that represents the data and data handling requirements of a company independent Engineering Change Management (ECM) reference process. ► ECM interaction scenarios and reference messages that enable automated execution of frequently occurring Engineering Change processes. ► Potential 20%–40% lead time reduction of the engineering change processes, and/or–enabled by increased frequency of engineering changes–improvement of overall product and process lifecycle knowledge. ► Method also applicable for Engineering Change Management in other industrial sectors and extendable to other business processes.
Reverse engineering in CAD model reconstruction of customized artificial joint
Medical Engineering & Physics
