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Sample records for computer-aided detection system

  1. Evaluation of computer-aided detection and diagnosis systems.

    Science.gov (United States)

    Petrick, Nicholas; Sahiner, Berkman; Armato, Samuel G; Bert, Alberto; Correale, Loredana; Delsanto, Silvia; Freedman, Matthew T; Fryd, David; Gur, David; Hadjiiski, Lubomir; Huo, Zhimin; Jiang, Yulei; Morra, Lia; Paquerault, Sophie; Raykar, Vikas; Samuelson, Frank; Summers, Ronald M; Tourassi, Georgia; Yoshida, Hiroyuki; Zheng, Bin; Zhou, Chuan; Chan, Heang-Ping

    2013-08-01

    Computer-aided detection and diagnosis (CAD) systems are increasingly being used as an aid by clinicians for detection and interpretation of diseases. Computer-aided detection systems mark regions of an image that may reveal specific abnormalities and are used to alert clinicians to these regions during image interpretation. Computer-aided diagnosis systems provide an assessment of a disease using image-based information alone or in combination with other relevant diagnostic data and are used by clinicians as a decision support in developing their diagnoses. While CAD systems are commercially available, standardized approaches for evaluating and reporting their performance have not yet been fully formalized in the literature or in a standardization effort. This deficiency has led to difficulty in the comparison of CAD devices and in understanding how the reported performance might translate into clinical practice. To address these important issues, the American Association of Physicists in Medicine (AAPM) formed the Computer Aided Detection in Diagnostic Imaging Subcommittee (CADSC), in part, to develop recommendations on approaches for assessing CAD system performance. The purpose of this paper is to convey the opinions of the AAPM CADSC members and to stimulate the development of consensus approaches and "best practices" for evaluating CAD systems. Both the assessment of a standalone CAD system and the evaluation of the impact of CAD on end-users are discussed. It is hoped that awareness of these important evaluation elements and the CADSC recommendations will lead to further development of structured guidelines for CAD performance assessment. Proper assessment of CAD system performance is expected to increase the understanding of a CAD system's effectiveness and limitations, which is expected to stimulate further research and development efforts on CAD technologies, reduce problems due to improper use, and eventually improve the utility and efficacy of CAD in

  2. Efficacy of computer-aided detection system for screening mammography

    International Nuclear Information System (INIS)

    Saito, Mioko; Ohnuki, Koji; Yamada, Takayuki; Saito, Haruo; Ishibashi, Tadashi; Ohuchi, Noriaki; Takahashi, Shoki

    2002-01-01

    A study was conducted to evaluate the efficacy of a computer-aided detection (CAD) system for screening mammography (MMG). Screening mammograms of 2,231 women aged over 50 yr were examined. Medio-lateral oblique (MLO) images were obtained, and two expert observers interpreted the mammograms by consensus. First, each mammogram was interpreted without the assistance of CAD, followed immediately by a re-evaluation of areas marked by the CAD system. Data were recorded to measure the effect of CAD on the recall rate, cancer detection rate and detection rate of masses, microcalcifications and other findings. The CAD system increased the recall rate from 2.3% to 2.6%. Six recalled cases were diagnosed as breast cancer pathologically, and CAD detected all of these lesions. Seven additional cases in which CAD detected abnormal findings had no malignancy. The detection rate of CAD for microcalcifications was high (95.0%). However, the detection rate for mass lesions and other findings was low (29.2% and 25.0% respectively). The false positivity rate was 0.13/film for microcalcifications, and 0.25/film for mass lesions. The efficacy of the CAD system for detecting microcalcifications on screening mammograms was confirmed. However, the low detection rate of mass lesions and relatively high rate of false positivity need to be further improved. (author)

  3. Computer Aided Diagnosis System for Early Lung Cancer Detection

    Directory of Open Access Journals (Sweden)

    Fatma Taher

    2015-11-01

    Full Text Available Lung cancer continues to rank as the leading cause of cancer deaths worldwide. One of the most promising techniques for early detection of cancerous cells relies on sputum cell analysis. This was the motivation behind the design and the development of a new computer aided diagnosis (CAD system for early detection of lung cancer based on the analysis of sputum color images. The proposed CAD system encompasses four main processing steps. First is the preprocessing step which utilizes a Bayesian classification method using histogram analysis. Then, in the second step, mean shift segmentation is applied to segment the nuclei from the cytoplasm. The third step is the feature analysis. In this step, geometric and chromatic features are extracted from the nucleus region. These features are used in the diagnostic process of the sputum images. Finally, the diagnosis is completed using an artificial neural network and support vector machine (SVM for classifying the cells into benign or malignant. The performance of the system was analyzed based on different criteria such as sensitivity, specificity and accuracy. The evaluation was carried out using Receiver Operating Characteristic (ROC curve. The experimental results demonstrate the efficiency of the SVM classifier over other classifiers, with 97% sensitivity and accuracy as well as a significant reduction in the number of false positive and false negative rates.

  4. Reproducibility of computer-aided detection system in digital mammograms

    International Nuclear Information System (INIS)

    Kim, Seung Ja; Cho, Nariya; Cha, Joo Hee; Chung, Hye Kyung; Lee, Sin Ho; Cho, Kyung Soo; Kim, Sun Mi; Moon, Woo Kyung

    2005-01-01

    To evaluate the reproducibility of the computer-aided detection (CAD) system for digital mammograms. We applied the CAD system (ImageChecker M1000-DM, version 3.1; R2 Technology) to full field digital mammograms. These mammograms were taken twice at an interval of 10-45 days (mean:25 days) for 34 preoperative patients (breast cancer n=27, benign disease n=7, age range:20-66 years, mean age:47.9 years). On the mammograms, lesions were visible in 19 patients and these were depicted as 15 masses and 12 calcification clusters. We analyzed the sensitivity, the false positive rate (FPR) and the reproducibility of the CAD marks. The broader sensitivities of the CAD system were 80% (12 of 15), 67%(10 of 15) for masses and those for calcification clusters were 100% (12 of 12). The strict sensitivities were 50% (15 of 30) and 50% (15 of 30) for masses and 92% (22 of 24) and 79% (19 of 24) for the clusters. The FPR for the masses was 0.21-0.22/image, the FPR for the clusters was 0.03-0.04/image and the total FPR was 0.24-0.26/image. Among 132 mammography images, the identical images regardless of the existence of CAD marks were 59% (78 of 132), and the identical images with CAD marks were 22% (15 of 69). The reproducibility of the CAD marks for the true positive mass was 67% (12 of 18) and 71% (17 of 24) for the true positive cluster. The reproducibility of CAD marks for the false positive mass was 8% (4 of 53), and the reproducibility of CAD marks for the false positive clusters was 14% (1 of 7). The reproducibility of the total mass marks was 23% (16 of 71), and the reproducibility of the total cluster marks was 58% (18 of 31). CAD system showed higher sensitivity and reproducibility of CAD marks for the calcification clusters which are related to breast cancer. Yet the overall reproducibility of CAD marks was low; therefore, the CAD system must be applied considering this limitation

  5. Computer-aided system for detecting runway incursions

    Science.gov (United States)

    Sridhar, Banavar; Chatterji, Gano B.

    1994-07-01

    A synthetic vision system for enhancing the pilot's ability to navigate and control the aircraft on the ground is described. The system uses the onboard airport database and images acquired by external sensors. Additional navigation information needed by the system is provided by the Inertial Navigation System and the Global Positioning System. The various functions of the system, such as image enhancement, map generation, obstacle detection, collision avoidance, guidance, etc., are identified. The available technologies, some of which were developed at NASA, that are applicable to the aircraft ground navigation problem are noted. Example images of a truck crossing the runway while the aircraft flies close to the runway centerline are described. These images are from a sequence of images acquired during one of the several flight experiments conducted by NASA to acquire data to be used for the development and verification of the synthetic vision concepts. These experiments provide a realistic database including video and infrared images, motion states from the Inertial Navigation System and the Global Positioning System, and camera parameters.

  6. Lung nodule detection on chest CT: evaluation of a computer-aided detection (CAD) system

    International Nuclear Information System (INIS)

    Lee, In Jae; Gamsu, Gordon; Czum, Julianna; Johnson, Rebecca; Chakrapani, Sanjay; Wu, Ning

    2005-01-01

    To evaluate the capacity of a computer-aided detection (CAD) system to detect lung nodules in clinical chest CT. A total of 210 consecutive clinical chest CT scans and their reports were reviewed by two chest radiologists and 70 were selected (33 without nodules and 37 with 1-6 nodules, 4-15.4 mm in diameter). The CAD system (ImageChecker CT LN-1000) developed by R2 Technology, Inc. (Sunnyvale, CA) was used. Its algorithm was designed to detect nodules with a diameter of 4-20 mm. The two chest radiologists working with the CAD system detected a total of 78 nodules. These 78 nodules form the database for this study. Four independent observers interpreted the studies with and without the CAD system. The detection rates of the four independent observers without CAD were 81% (63/78), 85% (66/78), 83% (65/78), and 83% (65/78), respectively. With CAD their rates were 87% (68/78), 85% (66/78), 86% (67/78), and 85% (66/78), respectively. The differences between these two sets of detection rates did not reach statistical significance. In addition, CAD detected eight nodules that were not mentioned in the original clinical radiology reports. The CAD system produced 1.56 false-positive nodules per CT study. The four test observers had 0, 0.1, 0.17, and 0.26 false-positive results per study without CAD and 0.07, 0.2, 0.23, and 0.39 with CAD, respectively. The CAD system can assist radiologists in detecting pulmonary nodules in chest CT, but with a potential increase in their false positive rates. Technological improvements to the system could increase the sensitivity and specificity for the detection of pulmonary nodules and reduce these false-positive results

  7. A Robust and Fast System for CTC Computer-Aided Detection of Colorectal Lesions

    Directory of Open Access Journals (Sweden)

    Gareth Beddoe

    2010-01-01

    Full Text Available We present a complete, end-to-end computer-aided detection (CAD system for identifying lesions in the colon, imaged with computed tomography (CT. This system includes facilities for colon segmentation, candidate generation, feature analysis, and classification. The algorithms have been designed to offer robust performance to variation in image data and patient preparation. By utilizing efficient 2D and 3D processing, software optimizations, multi-threading, feature selection, and an optimized cascade classifier, the CAD system quickly determines a set of detection marks. The colon CAD system has been validated on the largest set of data to date, and demonstrates excellent performance, in terms of its high sensitivity, low false positive rate, and computational efficiency.

  8. Computer aided detection system for lung cancer using computer tomography scans

    Science.gov (United States)

    Mahesh, Shanthi; Rakesh, Spoorthi; Patil, Vidya C.

    2018-04-01

    Lung Cancer is a disease can be defined as uncontrolled cell growth in tissues of the lung. If we detect the Lung Cancer in its early stage, then that could be the key of its cure. In this work the non-invasive methods are studied for assisting in nodule detection. It supplies a Computer Aided Diagnosis System (CAD) for early detection of lung cancer nodules from the Computer Tomography (CT) images. CAD system is the one which helps to improve the diagnostic performance of radiologists in their image interpretations. The main aim of this technique is to develop a CAD system for finding the lung cancer using the lung CT images and classify the nodule as Benign or Malignant. For classifying cancer cells, SVM classifier is used. Here, image processing techniques have been used to de-noise, to enhance, for segmentation and edge detection of an image is used to extract the area, perimeter and shape of nodule. The core factors of this research are Image quality and accuracy.

  9. Computer-aided detection in CT colonography: initial clinical experience using a prototype system

    International Nuclear Information System (INIS)

    Graser, A.; Geisbuesch, S.; Reiser, M.F.; Becker, C.R.; Kolligs, F.T.; Schaefer, C.; Mang, T.

    2007-01-01

    Computer-aided detection (CAD) algorithms help to detect colonic polyps at CT colonography (CTC). The purpose of this study was to evaluate the accuracy of CAD versus an expert reader in CTC. One hundred forty individuals (67 men, 73 women; mean age, 59 years) underwent screening 64-MDCT colonography after full cathartic bowel cleansing without fecal tagging. One expert reader interpreted supine and prone scans using a 3D workstation with integrated CAD used as ''second reader.'' The system's sensitivity for the detection of polyps, the number of false-positive findings, and its running time were evaluated. Polyps were classified as small (≤5 mm), medium (6-9 mm), and large (≥10 mm). A total of 118 polyps (small, 85; medium, 19; large, 14) were found in 56 patients. CAD detected 72 polyps (61%) with an average of 2.2 false-positives. Sensitivity was 51% (43/85) for small, 90% (17/19) for medium, and 86% (12/14) for large polyps. For all polyps, per-patient sensitivity was 89% (50/56) for the radiologist and 73% (41/56) for CAD. For large and medium polyps, per-patient sensitivity was 100% for the radiologist, and 96% for CAD. In conclusion, CAD shows high sensitivity in the detection of clinically significant polyps with acceptable false-positive rates. (orig.)

  10. Computer-aided detection system for chest radiography: reducing report turnaround times of examinations with abnormalities.

    Science.gov (United States)

    Kao, E-Fong; Liu, Gin-Chung; Lee, Lo-Yeh; Tsai, Huei-Yi; Jaw, Twei-Shiun

    2015-06-01

    The ability to give high priority to examinations with pathological findings could be very useful to radiologists with large work lists who wish to first evaluate the most critical studies. A computer-aided detection (CAD) system for identifying chest examinations with abnormalities has therefore been developed. To evaluate the effectiveness of a CAD system on report turnaround times of chest examinations with abnormalities. The CAD system was designed to automatically mark chest examinations with possible abnormalities in the work list of radiologists interpreting chest examinations. The system evaluation was performed in two phases: two radiologists interpreted the chest examinations without CAD in phase 1 and with CAD in phase 2. The time information recorded by the radiology information system was then used to calculate the turnaround times. All chest examinations were reviewed by two other radiologists and were divided into normal and abnormal groups. The turnaround times for the examinations with pathological findings with and without the CAD system assistance were compared. The sensitivity and specificity of the CAD for chest abnormalities were 0.790 and 0.697, respectively, and use of the CAD system decreased the turnaround time for chest examinations with abnormalities by 44%. The turnaround times required for radiologists to identify chest examinations with abnormalities could be reduced by using the CAD system. This system could be useful for radiologists with large work lists who wish to first evaluate the most critical studies. © The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  11. Computer-aided pulmonary nodule detection. Performance of two CAD systems at different CT dose levels

    International Nuclear Information System (INIS)

    Hein, Patrick Alexander; Rogalla, P.; Klessen, C.; Lembcke, A.; Romano, V.C.

    2009-01-01

    Purpose: To evaluate the impact of dose reduction on the performance of computer-aided lung nodule detection systems (CAD) of two manufacturers by comparing respective CAD results on ultra-low-dose computed tomography (ULD-CT) and standard dose CT (SD-CT). Materials and Methods: Multi-slice computed tomography (MSCT) data sets of 26 patients (13 male and 13 female, patients 31 - 74 years old) were retrospectively selected for CAD analysis. Indication for CT examination was staging of a known primary malignancy or suspected pulmonary malignancy. CT images were consecutively acquired at 5 mAs (ULD-CT) and 75 mAs (SD-CT) with 120kV tube voltage (1 mm slice thickness). The standard of reference was determined by three experienced readers in consensus. CAD reading algorithms (pre-commercial CAD system, Philips, Netherlands: CAD-1; LungCARE, Siemens, Germany: CAD-2) were applied to the CT data sets. Results: Consensus reading identified 253 nodules on SD-CT and ULD-CT. Nodules ranged in diameter between 2 and 41 mm (mean diameter 4.8 mm). Detection rates were recorded with 72% and 62% (CAD-1 vs. CAD-2) for SD-CT and with 73% and 56% for ULD-CT. Median also positive rates per patient were calculated with 6 and 5 (CAD-1 vs. CAD-2) for SD-CT and with 8 and 3 for ULD-CT. After separate statistical analysis of nodules with diameters of 5 mm and greater, the detection rates increased to 83% and 61% for SD-CT and to 89% and 67% for ULD-CT (CAD-1 vs. CAD-2). For both CAD systems there were no significant differences between the detection rates for standard and ultra-low-dose data sets (p>0.05). Conclusion: Dose reduction of the underlying CT scan did not significantly influence nodule detection performance of the tested CAD systems. (orig.)

  12. Computer-aided detection system for lung cancer in computed tomography scans: Review and future prospects

    Science.gov (United States)

    2014-01-01

    Introduction The goal of this paper is to present a critical review of major Computer-Aided Detection systems (CADe) for lung cancer in order to identify challenges for future research. CADe systems must meet the following requirements: improve the performance of radiologists providing high sensitivity in the diagnosis, a low number of false positives (FP), have high processing speed, present high level of automation, low cost (of implementation, training, support and maintenance), the ability to detect different types and shapes of nodules, and software security assurance. Methods The relevant literature related to “CADe for lung cancer” was obtained from PubMed, IEEEXplore and Science Direct database. Articles published from 2009 to 2013, and some articles previously published, were used. A systemic analysis was made on these articles and the results were summarized. Discussion Based on literature search, it was observed that many if not all systems described in this survey have the potential to be important in clinical practice. However, no significant improvement was observed in sensitivity, number of false positives, level of automation and ability to detect different types and shapes of nodules in the studied period. Challenges were presented for future research. Conclusions Further research is needed to improve existing systems and propose new solutions. For this, we believe that collaborative efforts through the creation of open source software communities are necessary to develop a CADe system with all the requirements mentioned and with a short development cycle. In addition, future CADe systems should improve the level of automation, through integration with picture archiving and communication systems (PACS) and the electronic record of the patient, decrease the number of false positives, measure the evolution of tumors, evaluate the evolution of the oncological treatment, and its possible prognosis. PMID:24713067

  13. Computer-aided detection systems to improve lung cancer early diagnosis: state-of-the-art and challenges

    International Nuclear Information System (INIS)

    Traverso, A; Lopez Torres, E; Cerello, P; Fantacci, M E

    2017-01-01

    Lung cancer is one of the most lethal types of cancer, because its early diagnosis is not good enough. In fact, the detection of pulmonary nodule, potential lung cancers, in Computed Tomography scans is a very challenging and time-consuming task for radiologists. To support radiologists, researchers have developed Computer-Aided Diagnosis (CAD) systems for the automated detection of pulmonary nodules in chest Computed Tomography scans. Despite the high level of technological developments and the proved benefits on the overall detection performance, the usage of Computer-Aided Diagnosis in clinical practice is far from being a common procedure. In this paper we investigate the causes underlying this discrepancy and present a solution to tackle it: the M5L WEB- and Cloud-based on-demand Computer-Aided Diagnosis. In addition, we prove how the combination of traditional imaging processing techniques with state-of-art advanced classification algorithms allows to build a system whose performance could be much larger than any Computer-Aided Diagnosis developed so far. This outcome opens the possibility to use the CAD as clinical decision support for radiologists. (paper)

  14. Computer-aided detection systems to improve lung cancer early diagnosis: state-of-the-art and challenges

    Science.gov (United States)

    Traverso, A.; Lopez Torres, E.; Fantacci, M. E.; Cerello, P.

    2017-05-01

    Lung cancer is one of the most lethal types of cancer, because its early diagnosis is not good enough. In fact, the detection of pulmonary nodule, potential lung cancers, in Computed Tomography scans is a very challenging and time-consuming task for radiologists. To support radiologists, researchers have developed Computer-Aided Diagnosis (CAD) systems for the automated detection of pulmonary nodules in chest Computed Tomography scans. Despite the high level of technological developments and the proved benefits on the overall detection performance, the usage of Computer-Aided Diagnosis in clinical practice is far from being a common procedure. In this paper we investigate the causes underlying this discrepancy and present a solution to tackle it: the M5L WEB- and Cloud-based on-demand Computer-Aided Diagnosis. In addition, we prove how the combination of traditional imaging processing techniques with state-of-art advanced classification algorithms allows to build a system whose performance could be much larger than any Computer-Aided Diagnosis developed so far. This outcome opens the possibility to use the CAD as clinical decision support for radiologists.

  15. A computer-aided diagnosis system to detect pathologies in temporal subtraction images of chest radiographs

    Science.gov (United States)

    Looper, Jared; Harrison, Melanie; Armato, Samuel G.

    2016-03-01

    Radiologists often compare sequential radiographs to identify areas of pathologic change; however, this process is prone to error, as human anatomy can obscure the regions of change, causing the radiologists to overlook pathology. Temporal subtraction (TS) images can provide enhanced visualization of regions of change in sequential radiographs and allow radiologists to better detect areas of change in radiographs. Not all areas of change shown in TS images, however, are actual pathology. The purpose of this study was to create a computer-aided diagnostic (CAD) system that identifies which regions of change are caused by pathology and which are caused by misregistration of the radiographs used to create the TS image. The dataset used in this study contained 120 images with 74 pathologic regions on 54 images outlined by an experienced radiologist. High and low ("light" and "dark") gray-level candidate regions were extracted from the images using gray-level thresholding. Then, sampling techniques were used to address the class imbalance problem between "true" and "false" candidate regions. Next, the datasets of light candidate regions, dark candidate regions, and the combined set of light and dark candidate regions were used as training and testing data for classifiers by using five-fold cross validation. Of the classifiers tested (support vector machines, discriminant analyses, logistic regression, and k-nearest neighbors), the support vector machine on the combined candidates using synthetic minority oversampling technique (SMOTE) performed best with an area under the receiver operating characteristic curve value of 0.85, a sensitivity of 85%, and a specificity of 84%.

  16. Computer-aided instruction system

    International Nuclear Information System (INIS)

    Teneze, Jean Claude

    1968-01-01

    This research thesis addresses the use of teleprocessing and time sharing by the RAX IBM system and the possibility to introduce a dialog with the machine to develop an application in which the computer plays the role of a teacher for different pupils at the same time. Two operating modes are thus exploited: a teacher-mode and a pupil-mode. The developed CAI (computer-aided instruction) system comprises a checker to check the course syntax in teacher-mode, a translator to trans-code the course written in teacher-mode into a form which can be processes by the execution programme, and the execution programme which presents the course in pupil-mode

  17. Computer-aided detection system applied to full-field digital mammograms

    International Nuclear Information System (INIS)

    Vega Bolivar, Alfonso; Sanchez Gomez, Sonia; Merino, Paula; Alonso-Bartolome, Pilar; Ortega Garcia, Estrella; Munoz Cacho, Pedro; Hoffmeister, Jeffrey W.

    2010-01-01

    Background: Although mammography remains the mainstay for breast cancer screening, it is an imperfect examination with a sensitivity of 75-92% for breast cancer. Computer-aided detection (CAD) has been developed to improve mammographic detection of breast cancer. Purpose: To retrospectively estimate CAD sensitivity and false-positive rate with full-field digital mammograms (FFDMs). Material and Methods: CAD was used to evaluate 151 cases of ductal carcinoma in situ (DCIS) (n=48) and invasive breast cancer (n=103) detected with FFDM. Retrospectively, CAD sensitivity was estimated based on breast density, mammographic presentation, histopathology type, and lesion size. CAD false-positive rate was estimated with screening FFDMs from 200 women. Results: CAD detected 93% (141/151) of cancer cases: 97% (28/29) in fatty breasts, 94% (81/86) in breasts containing scattered fibroglandular densities, 90% (28/31) in heterogeneously dense breasts, and 80% (4/5) in extremely dense breasts. CAD detected 98% (54/55) of cancers manifesting as calcifications, 89% (74/83) as masses, and 100% (13/13) as mixed masses and calcifications. CAD detected 92% (73/79) of invasive ductal carcinomas, 89% (8/9) of invasive lobular carcinomas, 93% (14/15) of other invasive carcinomas, and 96% (46/48) of DCIS. CAD sensitivity for cancers 1-10 mm was 87% (47/54); 11-20 mm, 99% (70/71); 21-30 mm, 86% (12/14); and larger than 30 mm, 100% (12/12). The CAD false-positive rate was 2.5 marks per case. Conclusion: CAD with FFDM showed a high sensitivity in identifying cancers manifesting as calcifications or masses. CAD sensitivity was maintained in small lesions (1-20 mm) and invasive lobular carcinomas, which have lower mammographic sensitivity

  18. Computer-aided detection system applied to full-field digital mammograms

    Energy Technology Data Exchange (ETDEWEB)

    Vega Bolivar, Alfonso; Sanchez Gomez, Sonia; Merino, Paula; Alonso-Bartolome, Pilar; Ortega Garcia, Estrella (Dept. of Radiology, Univ. Marques of Valdecilla Hospital, Santander (Spain)), e-mail: avegab@telefonica.net; Munoz Cacho, Pedro (Dept. of Statistics, Univ. Marques of Valdecilla Hospital, Santander (Spain)); Hoffmeister, Jeffrey W. (iCAD, Inc., Nashua, NH (United States))

    2010-12-15

    Background: Although mammography remains the mainstay for breast cancer screening, it is an imperfect examination with a sensitivity of 75-92% for breast cancer. Computer-aided detection (CAD) has been developed to improve mammographic detection of breast cancer. Purpose: To retrospectively estimate CAD sensitivity and false-positive rate with full-field digital mammograms (FFDMs). Material and Methods: CAD was used to evaluate 151 cases of ductal carcinoma in situ (DCIS) (n=48) and invasive breast cancer (n=103) detected with FFDM. Retrospectively, CAD sensitivity was estimated based on breast density, mammographic presentation, histopathology type, and lesion size. CAD false-positive rate was estimated with screening FFDMs from 200 women. Results: CAD detected 93% (141/151) of cancer cases: 97% (28/29) in fatty breasts, 94% (81/86) in breasts containing scattered fibroglandular densities, 90% (28/31) in heterogeneously dense breasts, and 80% (4/5) in extremely dense breasts. CAD detected 98% (54/55) of cancers manifesting as calcifications, 89% (74/83) as masses, and 100% (13/13) as mixed masses and calcifications. CAD detected 92% (73/79) of invasive ductal carcinomas, 89% (8/9) of invasive lobular carcinomas, 93% (14/15) of other invasive carcinomas, and 96% (46/48) of DCIS. CAD sensitivity for cancers 1-10 mm was 87% (47/54); 11-20 mm, 99% (70/71); 21-30 mm, 86% (12/14); and larger than 30 mm, 100% (12/12). The CAD false-positive rate was 2.5 marks per case. Conclusion: CAD with FFDM showed a high sensitivity in identifying cancers manifesting as calcifications or masses. CAD sensitivity was maintained in small lesions (1-20 mm) and invasive lobular carcinomas, which have lower mammographic sensitivity

  19. Computer-aided system design

    Science.gov (United States)

    Walker, Carrie K.

    1991-01-01

    A technique has been developed for combining features of a systems architecture design and assessment tool and a software development tool. This technique reduces simulation development time and expands simulation detail. The Architecture Design and Assessment System (ADAS), developed at the Research Triangle Institute, is a set of computer-assisted engineering tools for the design and analysis of computer systems. The ADAS system is based on directed graph concepts and supports the synthesis and analysis of software algorithms mapped to candidate hardware implementations. Greater simulation detail is provided by the ADAS functional simulator. With the functional simulator, programs written in either Ada or C can be used to provide a detailed description of graph nodes. A Computer-Aided Software Engineering tool developed at the Charles Stark Draper Laboratory (CSDL CASE) automatically generates Ada or C code from engineering block diagram specifications designed with an interactive graphical interface. A technique to use the tools together has been developed, which further automates the design process.

  20. CAESY - COMPUTER AIDED ENGINEERING SYSTEM

    Science.gov (United States)

    Wette, M. R.

    1994-01-01

    Many developers of software and algorithms for control system design have recognized that current tools have limits in both flexibility and efficiency. Many forces drive the development of new tools including the desire to make complex system modeling design and analysis easier and the need for quicker turnaround time in analysis and design. Other considerations include the desire to make use of advanced computer architectures to help in control system design, adopt new methodologies in control, and integrate design processes (e.g., structure, control, optics). CAESY was developed to provide a means to evaluate methods for dealing with user needs in computer-aided control system design. It is an interpreter for performing engineering calculations and incorporates features of both Ada and MATLAB. It is designed to be reasonably flexible and powerful. CAESY includes internally defined functions and procedures, as well as user defined ones. Support for matrix calculations is provided in the same manner as MATLAB. However, the development of CAESY is a research project, and while it provides some features which are not found in commercially sold tools, it does not exhibit the robustness that many commercially developed tools provide. CAESY is written in C-language for use on Sun4 series computers running SunOS 4.1.1 and later. The program is designed to optionally use the LAPACK math library. The LAPACK math routines are available through anonymous ftp from research.att.com. CAESY requires 4Mb of RAM for execution. The standard distribution medium is a .25 inch streaming magnetic tape cartridge (QIC-24) in UNIX tar format. CAESY was developed in 1993 and is a copyrighted work with all copyright vested in NASA.

  1. Dynamic MRI-based computer aided diagnostic systems for early detection of kidney transplant rejection: A survey

    Science.gov (United States)

    Mostapha, Mahmoud; Khalifa, Fahmi; Alansary, Amir; Soliman, Ahmed; Gimel'farb, Georgy; El-Baz, Ayman

    2013-10-01

    Early detection of renal transplant rejection is important to implement appropriate medical and immune therapy in patients with transplanted kidneys. In literature, a large number of computer-aided diagnostic (CAD) systems using different image modalities, such as ultrasound (US), magnetic resonance imaging (MRI), computed tomography (CT), and radionuclide imaging, have been proposed for early detection of kidney diseases. A typical CAD system for kidney diagnosis consists of a set of processing steps including: motion correction, segmentation of the kidney and/or its internal structures (e.g., cortex, medulla), construction of agent kinetic curves, functional parameter estimation, diagnosis, and assessment of the kidney status. In this paper, we survey the current state-of-the-art CAD systems that have been developed for kidney disease diagnosis using dynamic MRI. In addition, the paper addresses several challenges that researchers face in developing efficient, fast and reliable CAD systems for the early detection of kidney diseases.

  2. Value of a Computer-aided Detection System Based on Chest Tomosynthesis Imaging for the Detection of Pulmonary Nodules.

    Science.gov (United States)

    Yamada, Yoshitake; Shiomi, Eisuke; Hashimoto, Masahiro; Abe, Takayuki; Matsusako, Masaki; Saida, Yukihisa; Ogawa, Kenji

    2018-04-01

    Purpose To assess the value of a computer-aided detection (CAD) system for the detection of pulmonary nodules on chest tomosynthesis images. Materials and Methods Fifty patients with and 50 without pulmonary nodules underwent both chest tomosynthesis and multidetector computed tomography (CT) on the same day. Fifteen observers (five interns and residents, five chest radiologists, and five abdominal radiologists) independently evaluated tomosynthesis images of 100 patients for the presence of pulmonary nodules in a blinded and randomized manner, first without CAD, then with the inclusion of CAD marks. Multidetector CT images served as the reference standard. Free-response receiver operating characteristic analysis was used for the statistical analysis. Results The pooled diagnostic performance of 15 observers was significantly better with CAD than without CAD (figure of merit [FOM], 0.74 vs 0.71, respectively; P = .02). The average true-positive fraction and false-positive rate per all cases with CAD were 0.56 and 0.26, respectively, whereas those without CAD were 0.47 and 0.20, respectively. Subanalysis showed that the diagnostic performance of interns and residents was significantly better with CAD than without CAD (FOM, 0.70 vs 0.62, respectively; P = .001), whereas for chest radiologists and abdominal radiologists, the FOM with CAD values were greater but not significantly: 0.80 versus 0.78 (P = .38) and 0.74 versus 0.73 (P = .65), respectively. Conclusion CAD significantly improved diagnostic performance in the detection of pulmonary nodules on chest tomosynthesis images for interns and residents, but provided minimal benefit for chest radiologists and abdominal radiologists. © RSNA, 2017 Online supplemental material is available for this article.

  3. Feasibility Study of a Generalized Framework for Developing Computer-Aided Detection Systems-a New Paradigm.

    Science.gov (United States)

    Nemoto, Mitsutaka; Hayashi, Naoto; Hanaoka, Shouhei; Nomura, Yukihiro; Miki, Soichiro; Yoshikawa, Takeharu

    2017-10-01

    We propose a generalized framework for developing computer-aided detection (CADe) systems whose characteristics depend only on those of the training dataset. The purpose of this study is to show the feasibility of the framework. Two different CADe systems were experimentally developed by a prototype of the framework, but with different training datasets. The CADe systems include four components; preprocessing, candidate area extraction, candidate detection, and candidate classification. Four pretrained algorithms with dedicated optimization/setting methods corresponding to the respective components were prepared in advance. The pretrained algorithms were sequentially trained in the order of processing of the components. In this study, two different datasets, brain MRA with cerebral aneurysms and chest CT with lung nodules, were collected to develop two different types of CADe systems in the framework. The performances of the developed CADe systems were evaluated by threefold cross-validation. The CADe systems for detecting cerebral aneurysms in brain MRAs and for detecting lung nodules in chest CTs were successfully developed using the respective datasets. The framework was shown to be feasible by the successful development of the two different types of CADe systems. The feasibility of this framework shows promise for a new paradigm in the development of CADe systems: development of CADe systems without any lesion specific algorithm designing.

  4. A computer-aided detection (CAD) system with a 3D algorithm for small acute intracranial hemorrhage

    Science.gov (United States)

    Wang, Ximing; Fernandez, James; Deshpande, Ruchi; Lee, Joon K.; Chan, Tao; Liu, Brent

    2012-02-01

    Acute Intracranial hemorrhage (AIH) requires urgent diagnosis in the emergency setting to mitigate eventual sequelae. However, experienced radiologists may not always be available to make a timely diagnosis. This is especially true for small AIH, defined as lesion smaller than 10 mm in size. A computer-aided detection (CAD) system for the detection of small AIH would facilitate timely diagnosis. A previously developed 2D algorithm shows high false positive rates in the evaluation based on LAC/USC cases, due to the limitation of setting up correct coordinate system for the knowledge-based classification system. To achieve a higher sensitivity and specificity, a new 3D algorithm is developed. The algorithm utilizes a top-hat transformation and dynamic threshold map to detect small AIH lesions. Several key structures of brain are detected and are used to set up a 3D anatomical coordinate system. A rule-based classification of the lesion detected is applied based on the anatomical coordinate system. For convenient evaluation in clinical environment, the CAD module is integrated with a stand-alone system. The CAD is evaluated by small AIH cases and matched normal collected in LAC/USC. The result of 3D CAD and the previous 2D CAD has been compared.

  5. Computer-aided system for cryogenic research facilities

    International Nuclear Information System (INIS)

    Gerasimov, V.P.; Zhelamsky, M.V.; Mozin, I.V.; Repin, S.S.

    1994-01-01

    A computer-aided system is developed for the more effective choice and optimization of the design and manufacturing technologies of the superconductor for the magnet system of the International Thermonuclear Experimental Reactor (ITER) with the aim to ensure the superconductor certification. The computer-aided system provides acquisition, processing, storage and display of data describing the proceeding tests, the detection of any parameter deviations and their analysis. Besides, it generates commands for the equipment switch off in emergency situations. ((orig.))

  6. Computer-aided detection system for masses in automated whole breast ultrasonography: development and evaluation of the effectiveness

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeoung Hyun [Dept. of Radiology, Ewha Womans University Mokdong Hospital, Ewha Womans University School of Medicine, Seoul (Korea, Republic of); Cha, Joo Hee; Kim, Nam Kug; Chang, Young Jun; Kim, Hak Hee [Dept. of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Ko, Myung Su [Health Screening and Promotion Center, Asan Medical Center, Seoul (Korea, Republic of); Choi, Young Wook [Korea Electrotechnology Research Institute, Ansan (Korea, Republic of)

    2014-04-15

    The aim of this study was to evaluate the performance of a proposed computer-aided detection (CAD) system in automated breast ultrasonography (ABUS). Eighty-nine two-dimensional images (20 cysts, 42 benign lesions, and 27 malignant lesions) were obtained from 47 patients who underwent ABUS (ACUSON S2000). After boundary detection and removal, we detected mass candidates by using the proposed adjusted Otsu's threshold; the threshold was adaptive to the variations of pixel intensities in an image. Then, the detected candidates were segmented. Features of the segmented objects were extracted and used for training/testing in the classification. In our study, a support vector machine classifier was adopted. Eighteen features were used to determine whether the candidates were true lesions or not. A five-fold cross validation was repeated 20 times for the performance evaluation. The sensitivity and the false positive rate per image were calculated, and the classification accuracy was evaluated for each feature. In the classification step, the sensitivity of the proposed CAD system was 82.67% (SD, 0.02%). The false positive rate was 0.26 per image. In the detection/segmentation step, the sensitivities for benign and malignant mass detection were 90.47% (38/42) and 92.59% (25/27), respectively. In the five-fold cross-validation, the standard deviation of pixel intensities for the mass candidates was the most frequently selected feature, followed by the vertical position of the centroids. In the univariate analysis, each feature had 50% or higher accuracy. The proposed CAD system can be used for lesion detection in ABUS and may be useful in improving the screening efficiency.

  7. Automatic detection of pulmonary nodules at spiral CT: clinical application of a computer-aided diagnosis system

    International Nuclear Information System (INIS)

    Wormanns, Dag; Fiebich, Martin; Saidi, Mustafa; Diederich, Stefan; Heindel, Walter

    2002-01-01

    The aim of this study was to evaluate a computer-aided diagnosis (CAD) workstation with automatic detection of pulmonary nodules at low-dose spiral CT in a clinical setting for early detection of lung cancer. Eighty-eight consecutive spiral-CT examinations were reported by two radiologists in consensus. All examinations were reviewed using a CAD workstation with a self-developed algorithm for automatic detection of pulmonary nodules. The algorithm is designed to detect nodules with diameters of at least 5 mm. A total of 153 nodules were detected with at least one modality (radiologists in consensus, CAD, 85 nodules with diameter <5 mm, 68 with diameter ≥5 mm). The results of automatic nodule detection were compared to nodules detected with any modality as gold standard. Computer-aided diagnosis correctly identified 26 of 59 (38%) nodules with diameters ≥5 mm detected by visual assessment by the radiologists; of these, CAD detected 44% (24 of 54) nodules without pleural contact. In addition, 12 nodules ≥5 mm were detected which were not mentioned in the radiologist's report but represented real nodules. Sensitivity for detection of nodules ≥5 mm was 85% (58 of 68) for radiologists and 38% (26 of 68) for CAD. There were 5.8±3.6 false-positive results of CAD per CT study. Computer-aided diagnosis improves detection of pulmonary nodules at spiral CT and is a valuable second opinion in a clinical setting for lung cancer screening despite of its still limited sensitivity. (orig.)

  8. Computer aided detection system for Osteoporosis using low dose thoracic 3D CT images

    Science.gov (United States)

    Tsuji, Daisuke; Matsuhiro, Mikio; Suzuki, Hidenobu; Kawata, Yoshiki; Niki, Noboru; Nakano, Yasutaka; Harada, Masafumi; Kusumoto, Masahiko; Tsuchida, Takaaki; Eguchi, Kenji; Kaneko, Masahiro

    2018-02-01

    The patient of osteoporosis is about 13 million people in Japan and it is one of healthy life problems in the aging society. It is necessary to do early stage detection and treatment in order to prevent the osteoporosis. Multi-slice CT technology has been improving the three dimensional (3D) image analysis with higher resolution and shorter scan time. The 3D image analysis of thoracic vertebra can be used for supporting to diagnosis of osteoporosis. This analysis can be used for lung cancer detection at the same time. We develop method of shape analysis and CT values of spongy bone for the detection osteoporosis. Osteoporosis and lung cancer screening show high extraction rate by the thoracic vertebral evaluation CT images. In addition, we created standard pattern of CT value per thoracic vertebra for male age group using 298 low dose data.

  9. EVALUATION OF A COMPUTER-AIDED SEMEN ANALYSIS SYSTEM WITH SPERM TAIL DETECTION

    NARCIS (Netherlands)

    WIJCHMAN, JG; DEWOLF, BTHM; JAGER, S

    The aim of this study was to evaluate the Stroemberg-Mika cell motion analyser (SM-CMA) which uses tail detection in order to discriminate between immotile spermatozoa and other particles. Analysis of the spermatozoa by the SM-CMA can easily be checked on a video monitor. The semen samples were from

  10. Computer-aided diagnostic system for detection of Hashimoto thyroiditis on ultrasound images from a Polish population.

    Science.gov (United States)

    Acharya, U Rajendra; Sree, S Vinitha; Krishnan, M Muthu Rama; Molinari, Filippo; Zieleźnik, Witold; Bardales, Ricardo H; Witkowska, Agnieszka; Suri, Jasjit S

    2014-02-01

    Computer-aided diagnostic (CAD) techniques aid physicians in better diagnosis of diseases by extracting objective and accurate diagnostic information from medical data. Hashimoto thyroiditis is the most common type of inflammation of the thyroid gland. The inflammation changes the structure of the thyroid tissue, and these changes are reflected as echogenic changes on ultrasound images. In this work, we propose a novel CAD system (a class of systems called ThyroScan) that extracts textural features from a thyroid sonogram and uses them to aid in the detection of Hashimoto thyroiditis. In this paradigm, we extracted grayscale features based on stationary wavelet transform from 232 normal and 294 Hashimoto thyroiditis-affected thyroid ultrasound images obtained from a Polish population. Significant features were selected using a Student t test. The resulting feature vectors were used to build and evaluate the following 4 classifiers using a 10-fold stratified cross-validation technique: support vector machine, decision tree, fuzzy classifier, and K-nearest neighbor. Using 7 significant features that characterized the textural changes in the images, the fuzzy classifier had the highest classification accuracy of 84.6%, sensitivity of 82.8%, specificity of 87.0%, and a positive predictive value of 88.9%. The proposed ThyroScan CAD system uses novel features to noninvasively detect the presence of Hashimoto thyroiditis on ultrasound images. Compared to manual interpretations of ultrasound images, the CAD system offers a more objective interpretation of the nature of the thyroid. The preliminary results presented in this work indicate the possibility of using such a CAD system in a clinical setting after evaluating it with larger databases in multicenter clinical trials.

  11. Computer-aided dispatching system design specification

    Energy Technology Data Exchange (ETDEWEB)

    Briggs, M.G.

    1997-12-16

    This document defines the performance requirements for a graphic display dispatching system to support Hanford Patrol Operations Center. This document reflects the as-built requirements for the system that was delivered by GTE Northwest, Inc. This system provided a commercial off-the-shelf computer-aided dispatching system and alarm monitoring system currently in operations at the Hanford Patrol Operations Center, Building 2721E. This system also provides alarm back-up capability for the Plutonium Finishing Plant (PFP).

  12. Computer-aided dispatching system design specification

    International Nuclear Information System (INIS)

    Briggs, M.G.

    1997-01-01

    This document defines the performance requirements for a graphic display dispatching system to support Hanford Patrol Operations Center. This document reflects the as-built requirements for the system that was delivered by GTE Northwest, Inc. This system provided a commercial off-the-shelf computer-aided dispatching system and alarm monitoring system currently in operations at the Hanford Patrol Operations Center, Building 2721E. This system also provides alarm back-up capability for the Plutonium Finishing Plant (PFP)

  13. Computer-aided polyp detection on CT colonography: Comparison of three systems in a high-risk human population

    International Nuclear Information System (INIS)

    Park, Hee Sun; Kim, Se Hyung; Kim, Jong Hyo; Lee, June-Goo; Kim, Sang Gyun; Lee, Jeong Min; Lee, Jae Young; Han, Joon Koo; Choi, Byung Ihn

    2010-01-01

    Purpose: To compare the detection performances of two commercial and one academic computer-aided diagnosis (CAD) systems for polyp detection on CT colonography (CTC) in a high-risk human population and to assess their detection characteristics. Materials and methods: This retrospective study had institutional review board approval, but informed consent was waived. Sixty-eight patients who were suspected of having colonic polyps and scheduled for colonoscopic polyp removal were included. After CTC was performed using a 64-row MDCT, two commercial (PEV, CAR) and one academic (Hessian matrix-based) CAD systems were applied to each CTC dataset. Colonoscopy using the segmental unblinded technique was performed as a standard of reference. Per-polyp and per-patient sensitivities were calculated and compared for each CAD system. The mean number of false-positives (FPs) and false-negatives (FNs) was computed and the causes of all FPs and FNs were analyzed. Results: A total of 151 polyps in 61 patients were detected (77 polyps <6 mm, 48 6-9.9 mm, 26 ≥ 10 mm). Per-polyp sensitivity for PEV, CAR, and Hessian matrix-based CAD were: 71.6%, 78.4%, and 83.8% for polyps ≥6 mm, and 88.5%, 96.2%, and 96.2% for polyps ≥10 mm. Per-patient sensitivity for polyps ≥6 mm was 80.4%, 89.1%, and 93.5%, and 87%, 95.7%, and 95.7% for polyps ≥10 mm, respectively. Per-polyp and per-patient sensitivities were not significantly different among the three CAD systems regardless of size threshold. Mean number of FPs was 6.9 for PEV, 7.3 for CAR, and 14 for Hessian matrix-based CAD. The most common cause of FPs were feces, followed by extracolonic findings, prominent folds and ileocecal valve, and rectal tube. The distribution of the causes of FPs was significantly different among the three systems. Conclusion: Sensitivity of the three CAD systems for polyp detection was comparable regardless of the polyp size threshold; however, the number of FPs was higher in the Hessian matrix-based CAD

  14. Computer aided training system development

    International Nuclear Information System (INIS)

    Midkiff, G.N.

    1987-01-01

    The first three phases of Training System Development (TSD) -- job and task analysis, curriculum design, and training material development -- are time consuming and labor intensive. The use of personal computers with a combination of commercial and custom-designed software resulted in a significant reduction in the man-hours required to complete these phases for a Health Physics Technician Training Program at a nuclear power station. This paper reports that each step in the training program project involved the use of personal computers: job survey data were compiled with a statistical package, task analysis was performed with custom software designed to interface with a commercial database management program. Job Performance Measures (tests) were generated by a custom program from data in the task analysis database, and training materials were drafted, edited, and produced using commercial word processing software

  15. When and why might a Computer Aided Detection (CAD) system interfere with visual search? An eye-tracking study

    Science.gov (United States)

    Drew, Trafton; Cunningham, Corbin; Wolfe, Jeremy

    2012-01-01

    Rational and Objectives Computer Aided Detection (CAD) systems are intended to improve performance. This study investigates how CAD might actually interfere with a visual search task. This is a laboratory study with implications for clinical use of CAD. Methods 47 naïve observers in two studies were asked to search for a target, embedded in 1/f2.4 noise while we monitored their eye-movements. For some observers, a CAD system marked 75% of targets and 10% of distractors while other observers completed the study without CAD. In Experiment 1, the CAD system’s primary function was to tell observers where the target might be. In Experiment 2, CAD provided information about target identity. Results In Experiment 1, there was a significant enhancement of observer sensitivity in the presence of CAD (t(22)=4.74, pCAD system were missed more frequently than equivalent targets in No CAD blocks of the experiment (t(22)=7.02, pCAD, but also no significant cost on sensitivity to unmarked targets (t(22)=0.6, p=n.s.). Finally, in both experiments, CAD produced reliable changes in eye-movements: CAD observers examined a lower total percentage of the search area than the No CAD observers (Ex 1: t(48)=3.05, pCAD signals do not combine with observers’ unaided performance in a straight-forward manner. CAD can engender a sense of certainty that can lead to incomplete search and elevated chances of missing unmarked stimuli. PMID:22958720

  16. Computer-aided detection system performance on current and previous digital mammograms in patients with contralateral metachronous breast cancer

    International Nuclear Information System (INIS)

    Kim, Seung Ja; Moon, Woo Kyung; Cho, Nariya; Chang, Jung Min

    2012-01-01

    Background: The computer-aided detection (CAD) system is widely used for screening mammography. The performance of the CAD system for contralateral breast cancer has not been reported for women with a history of breast cancer. Purpose: To retrospectively evaluate the performance of a CAD system on current and previous mammograms in patients with contralateral metachronous breast cancer. Material and Methods: During a 3-year period, 4945 postoperative patients had follow-up examinations, from whom we selected 55 women with contralateral breast cancers. Among them, 38 had visible malignant signs on the current mammograms. We analyzed the sensitivity and false-positive marks of the system on the current and previous mammograms according to lesion type and breast density. Results: The total visible lesion components on the current mammograms included 27 masses and 14 calcifications in 38 patients. The case-based sensitivity for all lesion types was 63.2% (24/38) with false-positive marks of 0.71 per patient. The lesion-based sensitivity for masses and calcifications was 59.3% (16/27) and 71.4% (10/14), respectively. The lesion-based sensitivity for masses in fatty and dense breasts was 68.8% (11/16) and 45.5% (5/11), respectively. The lesion-based sensitivity for calcifications in fatty and dense breasts was 100.0% (3/3) and 63.6% (7/11), respectively. The total visible lesion components on the previous mammograms included 13 masses and three calcifications in 16 patients, and the sensitivity for all lesion types was 31.3% (5/16) with false-positive marks of 0.81 per patient. On these mammograms, the sensitivity for masses and calcifications was 30.8% (4/13) and 33.3% (1/3), respectively. The sensitivity in fatty and dense breasts was 28.6% (2/7) and 33.3% (3/9), respectively. Conclusion: In the women with a history of breast cancer, the sensitivity of the CAD system in visible contralateral breast cancer was lower than in most previous reports using the same CAD

  17. Computer-aided power systems analysis

    CERN Document Server

    Kusic, George

    2008-01-01

    Computer applications yield more insight into system behavior than is possible by using hand calculations on system elements. Computer-Aided Power Systems Analysis: Second Edition is a state-of-the-art presentation of basic principles and software for power systems in steady-state operation. Originally published in 1985, this revised edition explores power systems from the point of view of the central control facility. It covers the elements of transmission networks, bus reference frame, network fault and contingency calculations, power flow on transmission networks, generator base power setti

  18. Computer-Aided Facilities Management Systems (CAFM).

    Science.gov (United States)

    Cyros, Kreon L.

    Computer-aided facilities management (CAFM) refers to a collection of software used with increasing frequency by facilities managers. The six major CAFM components are discussed with respect to their usefulness and popularity in facilities management applications: (1) computer-aided design; (2) computer-aided engineering; (3) decision support…

  19. Computer Aided Detection of Breast Masses in Digital Tomosynthesis

    National Research Council Canada - National Science Library

    Singh, Swatee; Lo, Joseph

    2008-01-01

    The purpose of this study was to investigate feasibility of computer-aided detection of masses and calcification clusters in breast tomosynthesis images and obtain reliable estimates of sensitivity...

  20. Computer aided system engineering for space construction

    Science.gov (United States)

    Racheli, Ugo

    1989-01-01

    This viewgraph presentation covers the following topics. Construction activities envisioned for the assembly of large platforms in space (as well as interplanetary spacecraft and bases on extraterrestrial surfaces) require computational tools that exceed the capability of conventional construction management programs. The Center for Space Construction is investigating the requirements for new computational tools and, at the same time, suggesting the expansion of graduate and undergraduate curricula to include proficiency in Computer Aided Engineering (CAE) though design courses and individual or team projects in advanced space systems design. In the center's research, special emphasis is placed on problems of constructability and of the interruptability of planned activity sequences to be carried out by crews operating under hostile environmental conditions. The departure point for the planned work is the acquisition of the MCAE I-DEAS software, developed by the Structural Dynamics Research Corporation (SDRC), and its expansion to the level of capability denoted by the acronym IDEAS**2 currently used for configuration maintenance on Space Station Freedom. In addition to improving proficiency in the use of I-DEAS and IDEAS**2, it is contemplated that new software modules will be developed to expand the architecture of IDEAS**2. Such modules will deal with those analyses that require the integration of a space platform's configuration with a breakdown of planned construction activities and with a failure modes analysis to support computer aided system engineering (CASE) applied to space construction.

  1. Screening mammography-detected cancers: the sensitivity of the computer-aided detection system as applied to full-field digital mammography

    International Nuclear Information System (INIS)

    Yang, Sang Kyu; Cho, Nariya; Ko, Eun Sook; Kim, Do Yeon; Moon, Woo Kyung

    2006-01-01

    We wanted to evaluate the sensitivity of the computer-aided detection (CAD) system for performing full-field digital mammography (FFDM) on the breast cancers that were originally detected by screening mammography. The CAD system (Image Checker v3.1, R2 Technology, Los Altos, Calif.) together with a full-field digital mammography system (Senographe 2000D, GE Medical Systems, Buc, France) was prospectively applied to the mammograms of 70 mammographically detected breast cancer patients (age range, 37-69; median age, 51 years) who had negative findings on their clinical examinations. The sensitivity of the CAD system, according to histopathologic findings and radiologic primary features (i.e, mass, microcalcifications or mass with microcalcifications) and also the false-positive marking rate were then determined. The CAD system correctly depicted 67 of 70 breast cancer lesions (97.5%). The CAD system marked 29 of 30 breast cancers that presented with microcalcifications only (sensitivity 96.7%) and all 18 breast cancers the presented with mass together with microcalcifications (sensitivity 100%). Twenty of the 22 lesions that appeared as a mass only were marked correctly by the CAD system (sensitivity 90.9%). The CAD system correctly depicted all 22 lesions of ductal carcinoma in situ (sensitivity: 100%), all 13 lesions of invasive ductal carcinoma with ductal carcinoma in situ (sensitivity: 100%) and the 1 lesion of invasive lobular carcinoma (sensitivity: 100%). Thirty one of the 34 lesions of invasive ductal carcinoma were marked correctly by the CAD system (sensitivity: 91.8%). The rate of false-positive marks was 0.21 mass marks per image and 0.16 microcalcification marks per image. The overall rate of false-positive marks was 0.37 per image. The CAD system using FFDM is useful for the detection of asymptomatic breast cancers, and it has a high overall tumor detection rate. The false negative cases were found in relatively small invasive ductal carcinoma

  2. Screening mammography-detected cancers: the sensitivity of the computer-aided detection system as applied to full-field digital mammography

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Sang Kyu; Cho, Nariya; Ko, Eun Sook; Kim, Do Yeon; Moon, Woo Kyung [College of Medicine Seoul National University and The Insititute of Radiation Medicine, Seoul National University Research Center, Seoul (Korea, Republic of)

    2006-04-15

    We wanted to evaluate the sensitivity of the computer-aided detection (CAD) system for performing full-field digital mammography (FFDM) on the breast cancers that were originally detected by screening mammography. The CAD system (Image Checker v3.1, R2 Technology, Los Altos, Calif.) together with a full-field digital mammography system (Senographe 2000D, GE Medical Systems, Buc, France) was prospectively applied to the mammograms of 70 mammographically detected breast cancer patients (age range, 37-69; median age, 51 years) who had negative findings on their clinical examinations. The sensitivity of the CAD system, according to histopathologic findings and radiologic primary features (i.e, mass, microcalcifications or mass with microcalcifications) and also the false-positive marking rate were then determined. The CAD system correctly depicted 67 of 70 breast cancer lesions (97.5%). The CAD system marked 29 of 30 breast cancers that presented with microcalcifications only (sensitivity 96.7%) and all 18 breast cancers the presented with mass together with microcalcifications (sensitivity 100%). Twenty of the 22 lesions that appeared as a mass only were marked correctly by the CAD system (sensitivity 90.9%). The CAD system correctly depicted all 22 lesions of ductal carcinoma in situ (sensitivity: 100%), all 13 lesions of invasive ductal carcinoma with ductal carcinoma in situ (sensitivity: 100%) and the 1 lesion of invasive lobular carcinoma (sensitivity: 100%). Thirty one of the 34 lesions of invasive ductal carcinoma were marked correctly by the CAD system (sensitivity: 91.8%). The rate of false-positive marks was 0.21 mass marks per image and 0.16 microcalcification marks per image. The overall rate of false-positive marks was 0.37 per image. The CAD system using FFDM is useful for the detection of asymptomatic breast cancers, and it has a high overall tumor detection rate. The false negative cases were found in relatively small invasive ductal carcinoma.

  3. [Clinical skills and outcomes of chair-side computer aided design and computer aided manufacture system].

    Science.gov (United States)

    Yu, Q

    2018-04-09

    Computer aided design and computer aided manufacture (CAD/CAM) technology is a kind of oral digital system which is applied to clinical diagnosis and treatment. It overturns the traditional pattern, and provides a solution to restore defect tooth quickly and efficiently. In this paper we mainly discuss the clinical skills of chair-side CAD/CAM system, including tooth preparation, digital impression, the three-dimensional design of prosthesis, numerical control machining, clinical bonding and so on, and review the outcomes of several common kinds of materials at the same time.

  4. PACS-Based Computer-Aided Detection and Diagnosis

    Science.gov (United States)

    Huang, H. K. (Bernie); Liu, Brent J.; Le, Anh HongTu; Documet, Jorge

    The ultimate goal of Picture Archiving and Communication System (PACS)-based Computer-Aided Detection and Diagnosis (CAD) is to integrate CAD results into daily clinical practice so that it becomes a second reader to aid the radiologist's diagnosis. Integration of CAD and Hospital Information System (HIS), Radiology Information System (RIS) or PACS requires certain basic ingredients from Health Level 7 (HL7) standard for textual data, Digital Imaging and Communications in Medicine (DICOM) standard for images, and Integrating the Healthcare Enterprise (IHE) workflow profiles in order to comply with the Health Insurance Portability and Accountability Act (HIPAA) requirements to be a healthcare information system. Among the DICOM standards and IHE workflow profiles, DICOM Structured Reporting (DICOM-SR); and IHE Key Image Note (KIN), Simple Image and Numeric Report (SINR) and Post-processing Work Flow (PWF) are utilized in CAD-HIS/RIS/PACS integration. These topics with examples are presented in this chapter.

  5. A computer-aided continuous assessment system

    Directory of Open Access Journals (Sweden)

    B. C.H. Turton

    1996-12-01

    Full Text Available Universities within the United Kingdom have had to cope with a massive expansion in undergraduate student numbers over the last five years (Committee of Scottish University Principals, 1993; CVCP Briefing Note, 1994. In addition, there has been a move towards modularization and a closer monitoring of a student's progress throughout the year. Since the price/performance ratio of computer systems has continued to improve, Computer- Assisted Learning (CAL has become an attractive option. (Fry, 1990; Benford et al, 1994; Laurillard et al, 1994. To this end, the Universities Funding Council (UFQ has funded the Teaching and Learning Technology Programme (TLTP. However universities also have a duty to assess as well as to teach. This paper describes a Computer-Aided Assessment (CAA system capable of assisting in grading students and providing feedback. In this particular case, a continuously assessed course (Low-Level Languages of over 100 students is considered. Typically, three man-days are required to mark one assessed piece of coursework from the students in this class. Any feedback on how the questions were dealt with by the student are of necessity brief. Most of the feedback is provided in a tutorial session that covers the pitfalls encountered by the majority of the students.

  6. Computer aided information system for a PWR

    International Nuclear Information System (INIS)

    Vaidian, T.A.; Karmakar, G.; Rajagopal, R.; Shankar, V.; Patil, R.K.

    1994-01-01

    The computer aided information system (CAIS) is designed with a view to improve the performance of the operator. CAIS assists the plant operator in an advisory and support role, thereby reducing the workload level and potential human errors. The CAIS as explained here has been designed for a PWR type KLT- 40 used in Floating Nuclear Power Stations (FNPS). However the underlying philosophy evolved in designing the CAIS can be suitably adopted for other type of nuclear power plants too (BWR, PHWR). Operator information is divided into three broad categories: a) continuously available information b) automatically available information and c) on demand information. Two in number touch screens are provided on the main control panel. One is earmarked for continuously available information and the other is dedicated for automatically available information. Both the screens can be used at the operator's discretion for on-demand information. Automatically available information screen overrides the on-demand information screens. In addition to the above, CAIS has the features of event sequence recording, disturbance recording and information documentation. CAIS design ensures that the operator is not overburdened with excess and unnecessary information, but at the same time adequate and well formatted information is available. (author). 5 refs., 4 figs

  7. Software For Computer-Aided Design Of Control Systems

    Science.gov (United States)

    Wette, Matthew

    1994-01-01

    Computer Aided Engineering System (CAESY) software developed to provide means to evaluate methods for dealing with users' needs in computer-aided design of control systems. Interpreter program for performing engineering calculations. Incorporates features of both Ada and MATLAB. Designed to be flexible and powerful. Includes internally defined functions, procedures and provides for definition of functions and procedures by user. Written in C language.

  8. COMPUTER-AIDED DETECTION OF ACINAR SHADOWS IN CHEST RADIOGRAPHS

    Directory of Open Access Journals (Sweden)

    Tao Xu

    2013-05-01

    Full Text Available Despite the technological advances in medical diagnosis, accurate detection of infectious tuberculosis (TB still poses challenges due to complex image features and thus infectious TB continues to be a public health problem of global proportions. Currently, the detection of TB is mainly conducted visually by radiologists examining chest radiographs (CXRs. To reduce the backlog of CXR examination and provide more precise quantitative assessment, computer-aided detection (CAD systems for potential lung lesions have been increasingly adopted and commercialized for clinical practice. CADs work as supporting tools to alert radiologists on suspected features that could have easily been neglected. In this paper, an effective CAD system aimed for acinar shadow regions detection in CXRs is proposed. This system exploits textural and photometric features analysis techniques which include local binary pattern (LBP, grey level co-occurrence matrix (GLCM and histogram of oriented gradients (HOG to analyze target regions in CXRs. Classification of acinar shadows using Adaboost is then deployed to verify the performance of a combination of these techniques. Comparative study in different image databases shows that the proposed CAD system delivers consistent high accuracy in detecting acinar shadows.

  9. Detection of simulated pulmonary nodules by single-exposure dual-energy computed radiography of the chest: effect of a computer-aided diagnosis system (Part 2)

    International Nuclear Information System (INIS)

    Kido, Shoji; Kuriyama, Keiko; Kuroda, Chikazumi; Nakamura, Hironobu; Ito, Wataru; Shimura, Kazuo; Kato, Hisatoyo

    2002-01-01

    Objective: To evaluate the performance of the computer-aided diagnosis (CAD) scheme on the detection of pulmonary nodules (PNs) in single-exposure dual-energy subtraction computed radiography (CR) images of the chest, and to evaluate the effect of this CAD scheme on radiologists' detectabilities. Methods and material: We compared the detectability by the CAD scheme with the detectability by 12 observers by using conventional CR (C-CR) and bone-subtracted CR (BS-CR) images of 25 chest phantoms with a low-contrast nylon nodule. Results: Both in the CAD scheme and for the observers, the detectability of BS-CR images was superior to that of C-CR images (P<0.005). The detection performance of the CAD scheme was equal to that of the observers. The nodules detected by the CAD did not necessarily coincide with those by the observers. Thus, if observers can use the results of the CAD system as a 'second opinion', their detectabilities increase. Conclusion: The CAD system for detection of PNs in the single-exposure dual-energy subtraction method is promising for improving radiologists' detectabilities of PNs

  10. Article Commentary: Computer-Aided Detection of Breast Cancer — Have All Bases Been Covered?

    Directory of Open Access Journals (Sweden)

    Gautam S. Muralidhar

    2008-01-01

    Full Text Available The use of computer-aided detection (CAD systems in mammography has been the subject of intense research for many years. These systems have been developed with the aim of helping radiologists to detect signs of breast cancer. However, the effectiveness of CAD systems in practice has sparked recent debate. In this commentary, we argue that computer-aided detection will become an increasingly important tool for radiologists in the early detection of breast cancer, but there are some important issues that need to be given greater focus in designing CAD systems if they are to reach their full potential.

  11. Computer-Aided Detection of Polyps in CT Colonography Using Logistic Regression

    NARCIS (Netherlands)

    Van Ravesteijn, V.F.; Van Wijk, C.; Vos, F.M.; Truyen, R.; Peters, J.F.; Stoker, J.; Van Vliet, L.J.

    2010-01-01

    We present a computer-aided detection (CAD) system for computed tomography colonography that orders the polyps according to clinical relevance. TheCADsystem consists of two steps: candidate detection and supervised classification. The characteristics of the detection step lead to specific choices

  12. Impact on breast cancer diagnosis in a multidisciplinary unit after the incorporation of mammography digitalization and computer-aided detection systems.

    Science.gov (United States)

    Romero, Cristina; Varela, Celia; Muñoz, Enriqueta; Almenar, Asunción; Pinto, Jose María; Botella, Miguel

    2011-12-01

    The purpose of this article is to evaluate the impact on the diagnosis of breast cancer of implementing full-field digital mammography (FFDM) in a multidisciplinary breast pathology unit and, 1 year later, the addition of a computer-aided detection (CAD) system. A total of 13,453 mammograms performed between January and July of the years 2004, 2006, and 2007 were retrospectively reviewed using conventional mammography, digital mammography, and digital mammography plus CAD techniques. Mammograms were classified into two subsets: screening and diagnosis. Variables analyzed included cancer detection rate, rate of in situ carcinoma, tumor size at detection, biopsy rate, and positive predictive value of biopsy. FFDM increased the cancer detection rate, albeit not statistically significantly. The detection rate of in situ carcinoma increased significantly using FFDM plus CAD compared with conventional technique (36.8% vs 6.7%; p = 0.05 without Bonferroni statistical correction) for the screening dataset. Relative to conventional mammography, tumor size at detection decreased with digital mammography (T1, 61.5% vs 88%; p = 0.018) and with digital mammography plus CAD (T1, 79.7%; p = 0.03 without Bonferroni statistical correction). Biopsy rates in the general population increased significantly using CAD (10.6/1000 for conventional mammography, 14.7/1000 for digital mammography, and 17.9/1000 for digital mammography plus CAD; p = 0.02). The positive predictive value of biopsy decreased slightly, but not significantly, for both subsets. The incorporation of new techniques has improved the performance of the breast unit by increasing the overall detection rates and earlier detection (smaller tumors), both leading to an increase in interventionism.

  13. Retrospective analysis of a Computer-Aided Detection (CAD) system in full-field digital mammography in correlation to tumor histology

    International Nuclear Information System (INIS)

    Obenauer, S.; Sohns, C.; Grabbe, E.; Werner, C.

    2005-01-01

    Purpose: to evaluate the usefulness of a computer-aided detection (CAD) system in full-field digital mammography in correlation to tumor histology. Material and methods: a total of 476 patients (226 patients with histologically proven malignant tumors, 250 healthy women) took part in this study. The mammograms were studied retrospectively, using the CAD system Image Checker. For 226 patients digital mammograms in MLO-projection were available. For 186 of these patients the CC-projection was also available. CAD markers that correlated with histologically proven carcinomas were considered to be true-positive markers. All other CAD markers were considered to be false-positive. Histologically proven carcinomas without markers were false-negative results. The dependence of the CAD markers placement upon the different carcinoma histologies was studied using the Chi-square test. Results: no significant difference could be proven for the detectability of malignant breast lesions of different histologic types. For the detectability of ductal carcinoma in situ (DCIS), invasive ductal carcinoma (IDC), invasive lobular carcinoma (ILC), lobular carcinoma in situ (LCIS), tubular carcinoma and ductulo-lobular carcinoma, the true positives were 71.1%, 75%, 70.7%, 70%, 60% and 80%, respectively, in the MLO projection and 83.9%, 75.9%, 81.8%, 77.8%, 87.5% and 33.3%, respectively, in the CC projection. There was an average of 0.5 false-positive markers per mammographic image. Conclusion: The histologic type of carcinoma seems to have no influence on detectability when using the CAD system. The high rate of false-positive markers shows, however, the limited specificity of the CAD system and that improvements are necessary. (orig.)

  14. A computer-aided detection system for rheumatoid arthritis MRI data interpretation and quantification of synovial activity

    DEFF Research Database (Denmark)

    Kubassove, Olga; Boesen, Mikael; Cimmino, Marco A

    2009-01-01

    and interpretation slow down development in this area. Existing scoring systems of especially synovitis are too rigid and insensitive to measure early treatment response and quantify inflammation. This study tested a novel automated, computer system for analysis of dynamic MRI data acquired from patients with RA...

  15. Development and clinical application of a computer-aided real-time feedback system for detecting in-bed physical activities.

    Science.gov (United States)

    Lu, Liang-Hsuan; Chiang, Shang-Lin; Wei, Shun-Hwa; Lin, Chueh-Ho; Sung, Wen-Hsu

    2017-08-01

    Being bedridden long-term can cause deterioration in patients' physiological function and performance, limiting daily activities and increasing the incidence of falls and other accidental injuries. Little research has been carried out in designing effective detecting systems to monitor the posture and status of bedridden patients and to provide accurate real-time feedback on posture. The purposes of this research were to develop a computer-aided system for real-time detection of physical activities in bed and to validate the system's validity and test-retest reliability in determining eight postures: motion leftward/rightward, turning over leftward/rightward, getting up leftward/rightward, and getting off the bed leftward/rightward. The in-bed physical activity detecting system consists mainly of a clinical sickbed, signal amplifier, a data acquisition (DAQ) system, and operating software for computing and determining postural changes associated with four load cell sensing components. Thirty healthy subjects (15 males and 15 females, mean age = 27.8 ± 5.3 years) participated in the study. All subjects were asked to execute eight in-bed activities in a random order and to participate in an evaluation of the test-retest reliability of the results 14 days later. Spearman's rank correlation coefficient was used to compare the system's determinations of postural states with researchers' recordings of postural changes. The test-retest reliability of the system's ability to determine postures was analyzed using the interclass correlation coefficient ICC(3,1). The system was found to exhibit high validity and accuracy (r = 0.928, p system was particularly accurate in detecting motion rightward (90%), turning over leftward (83%), sitting up leftward or rightward (87-93%), and getting off the bed (100%). The test-retest reliability ICC(3,1) value was 0.968 (p system developed in this study exhibits satisfactory validity and reliability in detecting changes in

  16. A computer-aided detection system for rheumatoid arthritis MRI data interpretation and quantification of synovial activity

    DEFF Research Database (Denmark)

    Kubassove, Olga; Boesen, Mikael; Cimmino, Marco A

    2009-01-01

    RATIONAL AND OBJECTIVE: Disease assessment and follow-up of rheumatoid arthritis (RA) patients require objective evaluation and quantification. Magnetic resonance imaging (MRI) has a large potential to supplement such information for the clinician, however, time spent on data reading...... and interpretation slow down development in this area. Existing scoring systems of especially synovitis are too rigid and insensitive to measure early treatment response and quantify inflammation. This study tested a novel automated, computer system for analysis of dynamic MRI data acquired from patients with RA......, Dynamika-RA, which incorporates efficient data processing and analysis techniques....

  17. Computer-aided protective system (CAPS)

    International Nuclear Information System (INIS)

    Squire, R.K.

    1988-01-01

    A method of improving the security of materials in transit is described. The system provides a continuously monitored position location system for the transport vehicle, an internal computer-based geographic delimiter that makes continuous comparisons of actual positions with the preplanned routing and schedule, and a tamper detection/reaction system. The position comparison is utilized to institute preprogrammed reactive measures if the carrier is taken off course or schedule, penetrated, or otherwise interfered with. The geographic locater could be an independent internal platform or an external signal-dependent system utilizing GPS, Loran or similar source of geographic information; a small (micro) computer could provide adequate memory and computational capacity; the insurance of integrity of the system indicates the need for a tamper-proof container and built-in intrusion sensors. A variant of the system could provide real-time transmission of the vehicle position and condition to a central control point for; such transmission could be encrypted to preclude spoofing

  18. A computer-aided detection system for rheumatoid arthritis MRI data interpretation and quantification of synovial activity

    International Nuclear Information System (INIS)

    Kubassova, Olga; Boesen, Mikael; Cimmino, Marco A.; Bliddal, Henning

    2010-01-01

    Rational and objective: Disease assessment and follow-up of rheumatoid arthritis (RA) patients require objective evaluation and quantification. Magnetic resonance imaging (MRI) has a large potential to supplement such information for the clinician, however, time spent on data reading and interpretation slow down development in this area. Existing scoring systems of especially synovitis are too rigid and insensitive to measure early treatment response and quantify inflammation. This study tested a novel automated, computer system for analysis of dynamic MRI data acquired from patients with RA, Dynamika-RA, which incorporates efficient data processing and analysis techniques. Materials and methods: 140 MRI scans from hands and wrists of 135 active RA patients and 5 healthy controls were processed using Dynamika-RA and evaluated with RAMRIS. To reduce patient motion artefacts, MRI data were processed using Dynamika-RA, which removed motion in 2D and 3D planes. Then synovial enhancement was visualised and qualified using a novel fully automated voxel-by-voxel analysis based algorithm. This algorithm was used to replace traditional region-of-interest (ROI) and subtraction methods, yielding observer independent quantitative results. Results: Conventional scoring performed by an observer took 30-45 min per dataset. Dynamika-RA reduced motion artefacts, visualised inflammation and quantified disease activity in less than 3 min. Data processing allowed increasing signal to noise ratio by a factor 3. Due to fully automated procedure of data processing, there was no intertest variation in the results. Conclusions: Algorithms incorporated into Dynamika-RA allow for the significant enhancement of data quality through eliminating motion artefacts and reduction of time for evaluation of synovial inflammation.

  19. Local pulmonary structure classification for computer-aided nodule detection

    Science.gov (United States)

    Bahlmann, Claus; Li, Xianlin; Okada, Kazunori

    2006-03-01

    We propose a new method of classifying the local structure types, such as nodules, vessels, and junctions, in thoracic CT scans. This classification is important in the context of computer aided detection (CAD) of lung nodules. The proposed method can be used as a post-process component of any lung CAD system. In such a scenario, the classification results provide an effective means of removing false positives caused by vessels and junctions thus improving overall performance. As main advantage, the proposed solution transforms the complex problem of classifying various 3D topological structures into much simpler 2D data clustering problem, to which more generic and flexible solutions are available in literature, and which is better suited for visualization. Given a nodule candidate, first, our solution robustly fits an anisotropic Gaussian to the data. The resulting Gaussian center and spread parameters are used to affine-normalize the data domain so as to warp the fitted anisotropic ellipsoid into a fixed-size isotropic sphere. We propose an automatic method to extract a 3D spherical manifold, containing the appropriate bounding surface of the target structure. Scale selection is performed by a data driven entropy minimization approach. The manifold is analyzed for high intensity clusters, corresponding to protruding structures. Techniques involve EMclustering with automatic mode number estimation, directional statistics, and hierarchical clustering with a modified Bhattacharyya distance. The estimated number of high intensity clusters explicitly determines the type of pulmonary structures: nodule (0), attached nodule (1), vessel (2), junction (>3). We show accurate classification results for selected examples in thoracic CT scans. This local procedure is more flexible and efficient than current state of the art and will help to improve the accuracy of general lung CAD systems.

  20. Computer-aided detection in breast MRI : a systematic review and meta-analysis

    NARCIS (Netherlands)

    Dorrius, Monique D.; Jansen-van der Weide, Marijke C.; van Ooijen, Peter M. A.; Pijnappel, Ruud M.; Oudkerk, Matthijs

    To evaluate the additional value of computer-aided detection (CAD) in breast MRI by assessing radiologists' accuracy in discriminating benign from malignant breast lesions. A literature search was performed with inclusion of relevant studies using a commercially available CAD system with automatic

  1. Computer-Aided Detection in Breast Magnetic Resonance Imaging: A Review

    NARCIS (Netherlands)

    Dorrius, M. D.; Van Ooijen, P.M.A.

    2008-01-01

    The aim of this study is to give an overview on the accuracy of the discrimination between benign and malignant breast lesions on MRI with and without the use of a computer-aided detection (CAD) system. One investigator selected relevant articles based on title and abstract. Ten articles were

  2. On Combining Multiple-Instance Learning and Active Learning for Computer-Aided Detection of Tuberculosis

    NARCIS (Netherlands)

    Melendez Rodriguez, J.C.; Ginneken, B. van; Maduskar, P.; Philipsen, R.H.H.M.; Ayles, H.; Sanchez, C.I.

    2016-01-01

    The major advantage of multiple-instance learning (MIL) applied to a computer-aided detection (CAD) system is that it allows optimizing the latter with case-level labels instead of accurate lesion outlines as traditionally required for a supervised approach. As shown in previous work, a MIL-based

  3. Computer aided detection of surgical retained foreign object for prevention

    International Nuclear Information System (INIS)

    Hadjiiski, Lubomir; Marentis, Theodore C.; Rondon, Lucas; Chan, Heang-Ping; Chaudhury, Amrita R.; Chronis, Nikolaos

    2015-01-01

    Purpose: Surgical retained foreign objects (RFOs) have significant morbidity and mortality. They are associated with approximately $1.5 × 10 9 annually in preventable medical costs. The detection accuracy of radiographs for RFOs is a mediocre 59%. The authors address the RFO problem with two complementary technologies: a three-dimensional (3D) gossypiboma micro tag, the μTag that improves the visibility of RFOs on radiographs, and a computer aided detection (CAD) system that detects the μTag. It is desirable for the CAD system to operate in a high specificity mode in the operating room (OR) and function as a first reader for the surgeon. This allows for fast point of care results and seamless workflow integration. The CAD system can also operate in a high sensitivity mode as a second reader for the radiologist to ensure the highest possible detection accuracy. Methods: The 3D geometry of the μTag produces a similar two dimensional (2D) depiction on radiographs regardless of its orientation in the human body and ensures accurate detection by a radiologist and the CAD. The authors created a data set of 1800 cadaver images with the 3D μTag and other common man-made surgical objects positioned randomly. A total of 1061 cadaver images contained a single μTag and the remaining 739 were without μTag. A radiologist marked the location of the μTag using an in-house developed graphical user interface. The data set was partitioned into three independent subsets: a training set, a validation set, and a test set, consisting of 540, 560, and 700 images, respectively. A CAD system with modules that included preprocessing μTag enhancement, labeling, segmentation, feature analysis, classification, and detection was developed. The CAD system was developed using the training and the validation sets. Results: On the training set, the CAD achieved 81.5% sensitivity with 0.014 false positives (FPs) per image in a high specificity mode for the surgeons in the OR and 96

  4. A Complete Interactive Graphical Computer-Aided Instruction System.

    Science.gov (United States)

    Abrams, Steven Selby

    The use of interactive graphics in computer-aided instruction systems is discussed with emphasis placed on two requirements of such a system. The first is the need to provide the teacher with a useful tool with which to design and modify teaching sessions tailored to the individual needs and capabilities of the students. The second is the…

  5. Computer-Aided dispatching system design specification

    International Nuclear Information System (INIS)

    Briggs, M.G.

    1996-01-01

    This document defines the performance requirements for a graphic display dispatching system to support Hanford Patrol emergency response. This system is defined as a Commercial-Off the-Shelf computer dispatching system providing both text and graphical display information while interfacing with the diverse reporting system within the Hanford Facility. This system also provided expansion capabilities to integrate Hanford Fire and the Occurrence Notification Center and provides back-up capabilities for the Plutonium Processing Facility

  6. Computer-Aided dispatching system design specification

    Energy Technology Data Exchange (ETDEWEB)

    Briggs, M.G.

    1996-09-27

    This document defines the performance requirements for a graphic display dispatching system to support Hanford Patrol emergency response. This document outlines the negotiated requirements as agreed to by GTE Northwest during technical contract discussions. This system defines a commercial off-the-shelf computer dispatching system providing both test and graphic display information while interfacing with diverse alarm reporting system within the Hanford Site. This system provided expansion capability to integrate Hanford Fire and the Occurrence Notification Center. The system also provided back-up capability for the Plutonium Processing Facility (PFP).

  7. Computer-aided control system design

    International Nuclear Information System (INIS)

    Lebenhaft, J.R.

    1986-01-01

    Control systems are typically implemented using conventional PID controllers, which are then tuned manually during plant commissioning to compensate for interactions between feedback loops. As plants increase in size and complexity, such controllers can fail to provide adequate process regulations. Multivariable methods can be utilized to overcome these limitations. At the Chalk River Nuclear Laboratories, modern control systems are designed and analyzed with the aid of MVPACK, a system of computer programs that appears to the user like a high-level calculator. The software package solves complicated control problems, and provides useful insight into the dynamic response and stability of multivariable systems

  8. Assisted supervision of a computer aided tele-operation system

    Energy Technology Data Exchange (ETDEWEB)

    Le Bars, H; Gravez, P; Fournier, R

    1994-12-31

    This paper talks about Computer Aided Tele-operation (CAT) in dismantling and maintenance of nuclear plants. The current research orientations at CEA, basic concepts of the supervision assistance system and the realisation of a prototype are presented. (TEC). 3 refs., 4 figs.

  9. Assisted supervision of a computer aided tele-operation system

    International Nuclear Information System (INIS)

    Le Bars, H.; Gravez, P.; Fournier, R.

    1994-01-01

    This paper talks about Computer Aided Tele-operation (CAT) in dismantling and maintenance of nuclear plants. The current research orientations at CEA, basic concepts of the supervision assistance system and the realisation of a prototype are presented. (TEC). 3 refs., 4 figs

  10. Computer Aided Education System SuperTest. Present and Prospective

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available This paper analyzes the testing and self-testing process for the Computer Aided Education System (CAES SuperTest, used at the Academy of Economic Studies of Chisinau, Moldova and recently implemented at the University of Bacau, Romania. We discuss here the future of this software, from the Information Society and Knowledge Society point of view.

  11. Interpretation Time Using a Concurrent-Read Computer-Aided Detection System for Automated Breast Ultrasound in Breast Cancer Screening of Women With Dense Breast Tissue.

    Science.gov (United States)

    Jiang, Yulei; Inciardi, Marc F; Edwards, Alexandra V; Papaioannou, John

    2018-05-24

    The purpose of this study was to compare diagnostic accuracy and interpretation time of screening automated breast ultrasound (ABUS) for women with dense breast tissue without and with use of a recently U.S. Food and Drug Administration-approved computer-aided detection (CAD) system for concurrent read. In a retrospective observer performance study, 18 radiologists interpreted a cancer-enriched set (i.e., cancer prevalence higher than in the original screening cohort) of 185 screening ABUS studies (52 with and 133 without breast cancer). These studies were from a large cohort of ABUS screened patients interpreted as BI-RADS density C or D. Each reader interpreted each case twice in a counterbalanced study, once without the CAD system and once with it, separated by 4 weeks. For each case, each reader identified abnormal findings and reported BI-RADS assessment category and level of suspicion for breast cancer. Interpretation time was recorded. Level of suspicion data were compared to evaluate diagnostic accuracy by means of the Dorfman-Berbaum-Metz method of jackknife with ANOVA ROC analysis. Interpretation times were compared by ANOVA. The ROC AUC was 0.848 with the CAD system, compared with 0.828 without it, for a difference of 0.020 (95% CI, -0.011 to 0.051) and was statistically noninferior to the AUC without the CAD system with respect to a margin of -0.05 (p = 0.000086). The mean interpretation time was 3 minutes 33 seconds per case without the CAD system and 2 minutes 24 seconds with it, for a difference of 1 minute 9 seconds saved (95% CI, 44-93 seconds; p = 0.000014), or a reduction in interpretation time to 67% of the time without the CAD system. Use of the concurrent-read CAD system for interpretation of screening ABUS studies of women with dense breast tissue who do not have symptoms is expected to make interpretation significantly faster and produce noninferior diagnostic accuracy compared with interpretation without the CAD system.

  12. Phased searching with NEAT in a time-scaled framework: experiments on a computer-aided detection system for lung nodules.

    Science.gov (United States)

    Tan, Maxine; Deklerck, Rudi; Cornelis, Jan; Jansen, Bart

    2013-11-01

    In the field of computer-aided detection (CAD) systems for lung nodules in computed tomography (CT) scans, many image features are presented and many artificial neural network (ANN) classifiers with various structural topologies are analyzed; frequently, the classifier topologies are selected by trial-and-error experiments. To avoid these trial and error approaches, we present a novel classifier that evolves ANNs using genetic algorithms, called "Phased Searching with NEAT in a Time or Generation-Scaled Framework", integrating feature selection with the classification task. We analyzed our method's performance on 360 CT scans from the public Lung Image Database Consortium database. We compare our method's performance with other more-established classifiers, namely regular NEAT, Feature-Deselective NEAT (FD-NEAT), fixed-topology ANNs, and support vector machines (SVMs) using ten-fold cross-validation experiments of all 360 scans. The results show that the proposed "Phased Searching" method performs better and faster than regular NEAT, better than FD-NEAT, and achieves sensitivities at 3 and 4 false positives (FP) per scan that are comparable with the fixed-topology ANN and SVM classifiers, but with fewer input features. It achieves a detection sensitivity of 83.0±9.7% with an average of 4FP/scan, for nodules with a diameter greater than or equal to 3mm. It also evolves networks with shorter evolution times and with lower complexities than regular NEAT (p=0.026 and pNEAT and by our approach shows that our approach searches for good solutions in lower dimensional search spaces, and evolves networks without superfluous structure. We have presented a novel approach that combines feature selection with the evolution of ANN topology and weights. Compared with the original threshold-based Phased Searching method of Green, our method requires fewer parameters and converges to the optimal network complexity required for the classification task at hand. The results of the

  13. Computer aided accountancy for tritium handling systems

    International Nuclear Information System (INIS)

    Spannagel, G.; Schmid, C.

    1993-03-01

    A program is presented which can be used in tritium bearing systems for inventory taking and accountancy purposes. In particular, a detailed description is given of the environment in which this program has been integrated. It is explained in which way a high user friendliness has been attained and which structures contribute to achieving the flexibility required. (orig.) [de

  14. Computer aided operation of complex systems

    International Nuclear Information System (INIS)

    Goodstein, L.P.

    1985-09-01

    Advanced technology is having the effect that industrial systems are becoming more highly automated and do not rely on human intervention for the control of normally planned and/or predicted situations. Thus the importance of the operator has shifted from being a manual controller to becoming more of a systems manager and supervisory controller. At the same time, the use of advanced information technology in the control room and its potential impact on human-machine capabilities places additional demands on the designer. This report deals with work carried out to describe the plant-operator relationship in order to systematize the design and evaluation of suitable information systems in the control room. This design process starts with the control requirements from the plant and transforms them into corresponding sets of decision-making tasks with appropriate allocation of responsibilities between computer and operator. To further effectivize this cooperation, appropriate information display and accession are identified. The conceptual work has been supported by experimental studies on a small-scale simulator. (author)

  15. Framework for computer-aided systems design

    International Nuclear Information System (INIS)

    Esselman, W.H.

    1992-01-01

    Advanced computer technology, analytical methods, graphics capabilities, and expert systems contribute to significant changes in the design process. Continued progress is expected. Achieving the ultimate benefits of these computer-based design tools depends on successful research and development on a number of key issues. A fundamental understanding of the design process is a prerequisite to developing these computer-based tools. In this paper a hierarchical systems design approach is described, and methods by which computers can assist the designer are examined. A framework is presented for developing computer-based design tools for power plant design. These tools include expert experience bases, tutorials, aids in decision making, and tools to develop the requirements, constraints, and interactions among subsystems and components. Early consideration of the functional tasks is encouraged. Methods of acquiring an expert's experience base is a fundamental research problem. Computer-based guidance should be provided in a manner that supports the creativity, heuristic approaches, decision making, and meticulousness of a good designer

  16. Development of computer-aided diagnosis systems in radiology

    International Nuclear Information System (INIS)

    Higashida, Yoshiharu; Arimura, Hidetaka; Kumazawa, Seiji; Morishita, Junji; Sakai, Shuji

    2006-01-01

    Computer-aided diagnosis (CAD) is a practice done by medical doctors based on computer image analysis as the second opinion, and CAD studies have been government-adopted projects. CAD is already on popular practice in the cancers of the breast by mammography, lung by flat plate and CT images, and large bowel by CT colonoscopy. This paper describes four examples of authors' actual CAD investigations. First, the temporal subtraction image analysis by CAD is for the detection of abnormality in the chest by radiographs taken at different times. Examples are shown in cases of interstitial pneumonia and lung cancer out of 34 patients with diffuse lung diseases. Second, development of CAD system is recorded for detection of aneurysm by the brain MR angiography (MRA). Third is the CAD detection of fascicles in cerebral white matters by the diffuse tensor MRI, which will help the surgery for brain tumors. Final is an automated patient recognition based on an image-matching technique using previous chest radiographs in the picture archiving and communication systems. This is on the radiograph giving biological fingerprints of the patients. CAD will be applied in a wider field of medicare not only in imaging technology. (T.I)

  17. A handheld computer-aided diagnosis system and simulated analysis

    Science.gov (United States)

    Su, Mingjian; Zhang, Xuejun; Liu, Brent; Su, Kening; Louie, Ryan

    2016-03-01

    This paper describes a Computer Aided Diagnosis (CAD) system based on cellphone and distributed cluster. One of the bottlenecks in building a CAD system for clinical practice is the storage and process of mass pathology samples freely among different devices, and normal pattern matching algorithm on large scale image set is very time consuming. Distributed computation on cluster has demonstrated the ability to relieve this bottleneck. We develop a system enabling the user to compare the mass image to a dataset with feature table by sending datasets to Generic Data Handler Module in Hadoop, where the pattern recognition is undertaken for the detection of skin diseases. A single and combination retrieval algorithm to data pipeline base on Map Reduce framework is used in our system in order to make optimal choice between recognition accuracy and system cost. The profile of lesion area is drawn by doctors manually on the screen, and then uploads this pattern to the server. In our evaluation experiment, an accuracy of 75% diagnosis hit rate is obtained by testing 100 patients with skin illness. Our system has the potential help in building a novel medical image dataset by collecting large amounts of gold standard during medical diagnosis. Once the project is online, the participants are free to join and eventually an abundant sample dataset will soon be gathered enough for learning. These results demonstrate our technology is very promising and expected to be used in clinical practice.

  18. Computer-Aided Detection of Kidney Tumor on Abdominal Computed Tomography Scans

    International Nuclear Information System (INIS)

    Kim, D.Y.; Park, J.W.

    2004-01-01

    Purpose: To implement a computer-aided detection system for kidney segmentation and kidney tumor detection on abdominal computed tomography (CT) scans. Material and Methods: Abdominal CT images were digitized with a film digitizer, and a gray-level threshold method was used to segment the kidney. Based on texture analysis performed on sample images of kidney tumors, a portion of the kidney tumor was selected as seed region for start point of the region-growing process. The average and standard deviations were used to detect the kidney tumor. Starting at the detected seed region, the region-growing method was used to segment the kidney tumor with intensity values used as an acceptance criterion for a homogeneous test. This test was performed to merge the neighboring region as kidney tumor boundary. These methods were applied on 156 transverse images of 12 cases of kidney tumors scanned using a G.E. Hispeed CT scanner and digitized with a Lumisys LS-40 film digitizer. Results: The computer-aided detection system resulted in a kidney tumor detection sensitivity of 85% and no false-positive findings. Conclusion: This computer-aided detection scheme was useful for kidney tumor detection and gave the characteristics of detected kidney tumors

  19. Computer Aided Design System for Developing Musical Fountain Programs

    Institute of Scientific and Technical Information of China (English)

    刘丹; 张乃尧; 朱汉城

    2003-01-01

    A computer aided design system for developing musical fountain programs was developed with multiple functions such as intelligent design, 3-D animation, manual modification and synchronized motion to make the development process more efficient. The system first analyzed the music form and sentiment using many basic features of the music to select a basic fountain program. Then, this program is simulated with 3-D animation and modified manually to achieve the desired results. Finally, the program is transformed to a computer control program to control the musical fountain in time with the music. A prototype system for the musical fountain was also developed. It was tested with many styles of music and users were quite satisfied with its performance. By integrating various functions, the proposed computer aided design system for developing musical fountain programs greatly simplified the design of the musical fountain programs.

  20. CADRIGS--computer aided design reliability interactive graphics system

    International Nuclear Information System (INIS)

    Kwik, R.J.; Polizzi, L.M.; Sticco, S.; Gerrard, P.B.; Yeater, M.L.; Hockenbury, R.W.; Phillips, M.A.

    1982-01-01

    An integrated reliability analysis program combining graphic representation of fault trees, automated data base loadings and reference, and automated construction of reliability code input files was developed. The functional specifications for CADRIGS, the computer aided design reliability interactive graphics system, are presented. Previously developed fault tree segments used in auxiliary feedwater system safety analysis were constructed on CADRIGS and, when combined, yielded results identical to those resulting from manual input to the same reliability codes

  1. Method of Computer-aided Instruction in Situation Control Systems

    Directory of Open Access Journals (Sweden)

    Anatoliy O. Kargin

    2013-01-01

    Full Text Available The article considers the problem of computer-aided instruction in context-chain motivated situation control system of the complex technical system behavior. The conceptual and formal models of situation control with practical instruction are considered. Acquisition of new behavior knowledge is presented as structural changes in system memory in the form of situational agent set. Model and method of computer-aided instruction represent formalization, based on the nondistinct theories by physiologists and cognitive psychologists.The formal instruction model describes situation and reaction formation and dependence on different parameters, effecting education, such as the reinforcement value, time between the stimulus, action and the reinforcement. The change of the contextual link between situational elements when using is formalized.The examples and results of computer instruction experiments of the robot device “LEGO MINDSTORMS NXT”, equipped with ultrasonic distance, touch, light sensors.

  2. The computer aided education and training system for accident management

    International Nuclear Information System (INIS)

    Yoneyama, Mitsuru; Kubota, Ryuji; Fujiwara, Tadashi; Sakuma, Hitoshi

    1999-01-01

    The education and training system for Accident Management was developed by the Japanese BWR group and Hitachi Ltd. The education and training system is composed of two systems. One is computer aided instruction (CAI) education system and the education and training system with computer simulations. Both systems are designed to be executed on personal computers. The outlines of the CAI education system and the education and training system with simulator are reported below. These systems provides plant operators and technical support center staff with the effective education and training for accident management. (author)

  3. 1000-Case Reader Study of Radiologists' Performance in Interpretation of Automated Breast Volume Scanner Images with a Computer-Aided Detection System.

    Science.gov (United States)

    Xu, Xiaojing; Bao, Lingyun; Tan, Yanjuan; Zhu, Luoxi; Kong, Fanlei; Wang, Wei

    2018-05-28

    The objective of our study was to assess, in a reader study, radiologists' performance in interpretation of automated breast volume scanner (ABVS) images with the aid of a computer-aided detection (CADe) system. Our study is a retrospective observer study with the purpose of investigating the effectiveness of using a CADe system as an aid for radiologists in interpretation of ABVS images. The multiple-reader, multiple-case study was designed to compare the diagnostic performance of radiologists with and without CADe. The study included 1000 cases selected from ABVS examinations in our institution in 2012. Among those cases were 206 malignant, 486 benign and 308 normal cases. The cancer cases were consecutive; the benign and normal cases were randomly selected. All malignant and benign cases were confirmed by biopsy or surgery, and normal cases were confirmed by 2-y follow-up. Reader performance was compared in terms of area under the receiver operating characteristic curve, sensitivity and specificity. Additionally, the reading time per case for each reader was recorded. Nine radiologists from our institution participated in the study. Three had more than 8 y of ultrasound experience and more than 4 y of ABVS experience (group A); 3 had more than 5 y of ultrasound experience (group B), and 3 had more than 1 y of ultrasound experience (group C). Both group B and group C had no ABVS experience. The CADe system used was the QVCAD System (QView Medical, Inc., Los Altos, CA, USA). It is designed to aid radiologists in searching for suspicious areas in ABVS images. CADe results are presented to the reader simultaneously with the ABVS images; that is, the radiologists read the ABVS images concurrently with the CADe results. The cases were randomly assigned for each reader into two equal-size groups, 1 and 2. Initially the readers read their group 1 cases with the aid of CADe and their group 2 cases without CADe. After a 1-mo washout period, they re-read their group 1

  4. A supervisor system for computer aided laser machining

    International Nuclear Information System (INIS)

    Mukherjee, J.K.

    1990-01-01

    Lasers achieve non divergent beam of short wavelength energy which can propagate through normal atmosphere with little divergence and can be focused on very fine points. The final high energy per unit area on target is highly localised and suitable for various types of machining at high speeds. The most notable factor is that this high energy spot can be located precisely using light-weight optical components. The laser-machining is very amenable to environmental conditions unlike electron beam and other techniques. Precision cutting and welding of nuclear materials in normal or non oxidising atmosphere can be done using this fairly easily. To achieve these objectives, development of a computer controlled laser machining system has been undertaken. The development project aims at building a computer aided machine with indegenous controller and medium power laser suitable for cutting, welding, and marking. This paper describes the integration of the various computer aided functions, spanning over the full range, from job-defining to final finished part-delivary, in computer aided laser machining. Various innovative features of the system that render it suitable for laser tool development as well as for special machining applications with user-friendliness have been covered. (author). 5 refs., 5 figs

  5. Computer aided system for parametric design of combination die

    Science.gov (United States)

    Naranje, Vishal G.; Hussein, H. M. A.; Kumar, S.

    2017-09-01

    In this paper, a computer aided system for parametric design of combination dies is presented. The system is developed using knowledge based system technique of artificial intelligence. The system is capable to design combination dies for production of sheet metal parts having punching and cupping operations. The system is coded in Visual Basic and interfaced with AutoCAD software. The low cost of the proposed system will help die designers of small and medium scale sheet metal industries for design of combination dies for similar type of products. The proposed system is capable to reduce design time and efforts of die designers for design of combination dies.

  6. A Learning Health Care System Using Computer-Aided Diagnosis.

    Science.gov (United States)

    Cahan, Amos; Cimino, James J

    2017-03-08

    Physicians intuitively apply pattern recognition when evaluating a patient. Rational diagnosis making requires that clinical patterns be put in the context of disease prior probability, yet physicians often exhibit flawed probabilistic reasoning. Difficulties in making a diagnosis are reflected in the high rates of deadly and costly diagnostic errors. Introduced 6 decades ago, computerized diagnosis support systems are still not widely used by internists. These systems cannot efficiently recognize patterns and are unable to consider the base rate of potential diagnoses. We review the limitations of current computer-aided diagnosis support systems. We then portray future diagnosis support systems and provide a conceptual framework for their development. We argue for capturing physician knowledge using a novel knowledge representation model of the clinical picture. This model (based on structured patient presentation patterns) holds not only symptoms and signs but also their temporal and semantic interrelations. We call for the collection of crowdsourced, automatically deidentified, structured patient patterns as means to support distributed knowledge accumulation and maintenance. In this approach, each structured patient pattern adds to a self-growing and -maintaining knowledge base, sharing the experience of physicians worldwide. Besides supporting diagnosis by relating the symptoms and signs with the final diagnosis recorded, the collective pattern map can also provide disease base-rate estimates and real-time surveillance for early detection of outbreaks. We explain how health care in resource-limited settings can benefit from using this approach and how it can be applied to provide feedback-rich medical education for both students and practitioners. ©Amos Cahan, James J Cimino. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 08.03.2017.

  7. Automatic computer aided analysis algorithms and system for adrenal tumors on CT images.

    Science.gov (United States)

    Chai, Hanchao; Guo, Yi; Wang, Yuanyuan; Zhou, Guohui

    2017-12-04

    The adrenal tumor will disturb the secreting function of adrenocortical cells, leading to many diseases. Different kinds of adrenal tumors require different therapeutic schedules. In the practical diagnosis, it highly relies on the doctor's experience to judge the tumor type by reading the hundreds of CT images. This paper proposed an automatic computer aided analysis method for adrenal tumors detection and classification. It consisted of the automatic segmentation algorithms, the feature extraction and the classification algorithms. These algorithms were then integrated into a system and conducted on the graphic interface by using MATLAB Graphic user interface (GUI). The accuracy of the automatic computer aided segmentation and classification reached 90% on 436 CT images. The experiments proved the stability and reliability of this automatic computer aided analytic system.

  8. Computer aided approach for qualitative risk assessment of engineered systems

    International Nuclear Information System (INIS)

    Crowley, W.K.; Arendt, J.S.; Fussell, J.B.; Rooney, J.J.; Wagner, D.P.

    1978-01-01

    This paper outlines a computer aided methodology for determining the relative contributions of various subsystems and components to the total risk associated with an engineered system. Major contributors to overall task risk are identified through comparison of an expected frequency density function with an established risk criterion. Contributions that are inconsistently high are also identified. The results from this analysis are useful for directing efforts for improving system safety and performance. An analysis of uranium hexafluoride handling risk at a gaseous diffusion uranium enrichment plant using a preliminary version of the computer program EXCON is briefly described and illustrated

  9. A computer aided treatment event recognition system in radiation therapy

    International Nuclear Information System (INIS)

    Xia, Junyi; Mart, Christopher; Bayouth, John

    2014-01-01

    Purpose: To develop an automated system to safeguard radiation therapy treatments by analyzing electronic treatment records and reporting treatment events. Methods: CATERS (Computer Aided Treatment Event Recognition System) was developed to detect treatment events by retrieving and analyzing electronic treatment records. CATERS is designed to make the treatment monitoring process more efficient by automating the search of the electronic record for possible deviations from physician's intention, such as logical inconsistencies as well as aberrant treatment parameters (e.g., beam energy, dose, table position, prescription change, treatment overrides, etc). Over a 5 month period (July 2012–November 2012), physicists were assisted by the CATERS software in conducting normal weekly chart checks with the aims of (a) determining the relative frequency of particular events in the authors’ clinic and (b) incorporating these checks into the CATERS. During this study period, 491 patients were treated at the University of Iowa Hospitals and Clinics for a total of 7692 fractions. Results: All treatment records from the 5 month analysis period were evaluated using all the checks incorporated into CATERS after the training period. About 553 events were detected as being exceptions, although none of them had significant dosimetric impact on patient treatments. These events included every known event type that was discovered during the trial period. A frequency analysis of the events showed that the top three types of detected events were couch position override (3.2%), extra cone beam imaging (1.85%), and significant couch position deviation (1.31%). The significant couch deviation is defined as the number of treatments where couch vertical exceeded two times standard deviation of all couch verticals, or couch lateral/longitudinal exceeded three times standard deviation of all couch laterals and longitudinals. On average, the application takes about 1 s per patient when

  10. A computer aided treatment event recognition system in radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Junyi, E-mail: junyi-xia@uiowa.edu; Mart, Christopher [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States); Bayouth, John [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, Iowa City, Iowa 52242 and Department of Human Oncology, University of Wisconsin - Madison, 600 Highland Avenue, K4/B55, Madison, Wisconsin 53792-0600 (United States)

    2014-01-15

    Purpose: To develop an automated system to safeguard radiation therapy treatments by analyzing electronic treatment records and reporting treatment events. Methods: CATERS (Computer Aided Treatment Event Recognition System) was developed to detect treatment events by retrieving and analyzing electronic treatment records. CATERS is designed to make the treatment monitoring process more efficient by automating the search of the electronic record for possible deviations from physician's intention, such as logical inconsistencies as well as aberrant treatment parameters (e.g., beam energy, dose, table position, prescription change, treatment overrides, etc). Over a 5 month period (July 2012–November 2012), physicists were assisted by the CATERS software in conducting normal weekly chart checks with the aims of (a) determining the relative frequency of particular events in the authors’ clinic and (b) incorporating these checks into the CATERS. During this study period, 491 patients were treated at the University of Iowa Hospitals and Clinics for a total of 7692 fractions. Results: All treatment records from the 5 month analysis period were evaluated using all the checks incorporated into CATERS after the training period. About 553 events were detected as being exceptions, although none of them had significant dosimetric impact on patient treatments. These events included every known event type that was discovered during the trial period. A frequency analysis of the events showed that the top three types of detected events were couch position override (3.2%), extra cone beam imaging (1.85%), and significant couch position deviation (1.31%). The significant couch deviation is defined as the number of treatments where couch vertical exceeded two times standard deviation of all couch verticals, or couch lateral/longitudinal exceeded three times standard deviation of all couch laterals and longitudinals. On average, the application takes about 1 s per patient when

  11. 3D computer-aided detection for digital breast tomosynthesis: Comparison with 2D computer-aided detection for digital mammography in the detection of calcifications

    Energy Technology Data Exchange (ETDEWEB)

    Chu, A Jung; Cho, Nariya; Chang, Jung Min; Kim, Won Hwa; Lee, Su Hyun; Song, Sung Eun; Shin, Sung Ui; Moon, Woo Kyung [Dept. of Radiology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul (Korea, Republic of)

    2017-08-15

    To retrospectively evaluate the performance of 3D computer-aided detection (CAD) for digital breast tomosynthesis (DBT) in the detection of calcifications in comparison with 2D CAD for digital mammography (DM). Between 2012 and 2013, both 3D CAD and 2D CAD systems were retrospectively applied to the calcification data set including 69 calcifications (31 malignant calcifications and 38 benign calcifications) and the normal data set including 20 bilateral normal mammograms. Each data set consisted of paired DBT and DM images. Sensitivities for the detection of malignant calcifications were calculated from the calcification data set. False-positive mark rates were calculated from the normal data set. They were compared between the two systems. Sensitivities of 3D CAD [100% (31/31) at levels 2, 1, and 0] were same as those of the 2D CAD system [100% (31/31) at levels 2 and 1] (p = 1.0, respectively). The mean value of false-positive marks per view with 3D CAD was higher than that with 2D CAD at level 2 (0.52 marks ± 0.91 vs. 0.07 marks ± 0.26, p = 0.009). 3D CAD for DBT showed equivalent sensitivity, albeit with a higher false-positive mark rate, than 2D CAD for DM in the detection of calcifications.

  12. Computer-aided auscultation learning system for nursing technique instruction.

    Science.gov (United States)

    Hou, Chun-Ju; Chen, Yen-Ting; Hu, Ling-Chen; Chuang, Chih-Chieh; Chiu, Yu-Hsien; Tsai, Ming-Shih

    2008-01-01

    Pulmonary auscultation is a physical assessment skill learned by nursing students for examining the respiratory system. Generally, a sound simulator equipped mannequin is used to group teach auscultation techniques via classroom demonstration. However, nursing students cannot readily duplicate this learning environment for self-study. The advancement of electronic and digital signal processing technologies facilitates simulating this learning environment. This study aims to develop a computer-aided auscultation learning system for assisting teachers and nursing students in auscultation teaching and learning. This system provides teachers with signal recording and processing of lung sounds and immediate playback of lung sounds for students. A graphical user interface allows teachers to control the measuring device, draw lung sound waveforms, highlight lung sound segments of interest, and include descriptive text. Effects on learning lung sound auscultation were evaluated for verifying the feasibility of the system. Fifteen nursing students voluntarily participated in the repeated experiment. The results of a paired t test showed that auscultative abilities of the students were significantly improved by using the computer-aided auscultation learning system.

  13. [A computer-aided image diagnosis and study system].

    Science.gov (United States)

    Li, Zhangyong; Xie, Zhengxiang

    2004-08-01

    The revolution in information processing, particularly the digitizing of medicine, has changed the medical study, work and management. This paper reports a method to design a system for computer-aided image diagnosis and study. Combined with some good idea of graph-text system and picture archives communicate system (PACS), the system was realized and used for "prescription through computer", "managing images" and "reading images under computer and helping the diagnosis". Also typical examples were constructed in a database and used to teach the beginners. The system was developed by the visual developing tools based on object oriented programming (OOP) and was carried into operation on the Windows 9X platform. The system possesses friendly man-machine interface.

  14. Computer aided systems human engineering: A hypermedia tool

    Science.gov (United States)

    Boff, Kenneth R.; Monk, Donald L.; Cody, William J.

    1992-01-01

    The Computer Aided Systems Human Engineering (CASHE) system, Version 1.0, is a multimedia ergonomics database on CD-ROM for the Apple Macintosh II computer, being developed for use by human system designers, educators, and researchers. It will initially be available on CD-ROM and will allow users to access ergonomics data and models stored electronically as text, graphics, and audio. The CASHE CD-ROM, Version 1.0 will contain the Boff and Lincoln (1988) Engineering Data Compendium, MIL-STD-1472D and a unique, interactive simulation capability, the Perception and Performance Prototyper. Its features also include a specialized data retrieval, scaling, and analysis capability and the state of the art in information retrieval, browsing, and navigation.

  15. Does Computer-aided Detection Assist in the Early Detection of Breast Cancer?

    International Nuclear Information System (INIS)

    Hukkinen, K.; Pamilo, M.

    2005-01-01

    Purpose: To evaluate whether breast cancers detected at screening are visible in previous mammograms, and to assess the performance of a computer-aided detection (CAD) system in detecting lesions in preoperative and previous mammograms. Material and Methods: Initial screening detected 67 women with 69 surgically verified breast cancers (Group A). An experienced screening radiologist retrospectively analyzed previous mammograms for visible lesions (Group B), noting in particular their size and morphology. Preoperative and previous mammograms were analyzed with CAD; a relatively inexperienced resident also analyzed previous mammograms. The performances of CAD and resident were then compared. Results: Of the 69 lesions identified, 36 were visible in previous mammograms. Of these 36 'missed' lesions, 14 were under 10 mm in diameter and 29 were mass lesions. The sensitivity of CAD was 81% in Group A and 64% in Group B. Small mass lesions were harder for CAD to detect. The specificity of CAD was 3% in Group A and 9% in Group B. Together, CAD and the resident found more 'missed' lesions than separately. Conclusion: Of the 69 breast cancers, 36 were visible in previous mammograms. CAD's sensitivity in detecting cancer lesions ranged from 64% to 81%, while specificity ranged from 9% to as low as 3%. CAD may be helpful if the radiologist is less subspecialized in mammography

  16. ARCHITECTURE OF WEB BASED COMPUTER-AIDED MANUFACTURING SYSTEM

    Directory of Open Access Journals (Sweden)

    N. E. Filyukov

    2014-09-01

    Full Text Available The paper deals with design of a web-based system for Computer-Aided Manufacturing (CAM. Remote applications and databases located in the "private cloud" are proposed to be the basis of such system. The suggested approach contains: service - oriented architecture, using web applications and web services as modules, multi-agent technologies for implementation of information exchange functions between the components of the system and the usage of PDM - system for managing technology projects within the CAM. The proposed architecture involves CAM conversion into the corporate information system that will provide coordinated functioning of subsystems based on a common information space, as well as parallelize collective work on technology projects and be able to provide effective control of production planning. A system has been developed within this architecture which gives the possibility for a rather simple technological subsystems connect to the system and implementation of their interaction. The system makes it possible to produce CAM configuration for a particular company on the set of developed subsystems and databases specifying appropriate access rights for employees of the company. The proposed approach simplifies maintenance of software and information support for CAM subsystems due to their central location in the data center. The results can be used as a basis for CAM design and testing within the learning process for development and modernization of the system algorithms, and then can be tested in the extended enterprise.

  17. The computer aided education and training system for accident management

    International Nuclear Information System (INIS)

    Yoneyama, Mitsuru; Masuda, Takahiro; Kubota, Ryuji; Fujiwara, Tadashi; Sakuma, Hitoshi

    2000-01-01

    Under severe accident conditions of a nuclear power plant, plant operators and technical support center (TSC) staffs will be under a amount of stress. Therefore, those individuals responsible for managing the plant should promote their understanding about the accident management and operations. Moreover, it is also important to train in ordinary times, so that they can carry out accident management operations effectively on severe accidents. Therefore, the education and training system which works on personal computers was developed by Japanese BWR group (Tokyo Electric Power Co.,Inc., Tohoku Electric Power Co. ,Inc., Chubu Electric Power Co. ,Inc., Hokuriku Electric Power Co.,Inc., Chugoku Electric Power Co.,Inc., Japan Atomic Power Co.,Inc.), and Hitachi, Ltd. The education and training system is composed of two systems. One is computer aided instruction (CAI) education system and the other is education and training system with a computer simulation. Both systems are designed to execute on MS-Windows(R) platform of personal computers. These systems provide plant operators and technical support center staffs with an effective education and training tool for accident management. TEPCO used the simulation system for the emergency exercise assuming the occurrence of hypothetical severe accident, and have performed an effective exercise in March, 2000. (author)

  18. Computer-aided detection of pulmonary nodules: influence of nodule characteristics on detection performance

    International Nuclear Information System (INIS)

    Marten, K.; Engelke, C.; Seyfarth, T.; Grillhoesl, A.; Obenauer, S.; Rummeny, E.J.

    2005-01-01

    AIM: To evaluate prospectively the influence of pulmonary nodule characteristics on detection performances of a computer-aided diagnosis (CAD) tool and experienced chest radiologists using multislice CT (MSCT). MATERIALS AND METHODS: MSCT scans of 20 consecutive patients were evaluated by a CAD system and two independent chest radiologists for presence of pulmonary nodules. Nodule size, position, margin, matrix characteristics, vascular and pleural attachments and reader confidence were recorded and data compared with an independent standard of reference. Statistical analysis for predictors influencing nodule detection or reader performance included chi-squared, retrograde stepwise conditional logistic regression with odds ratios and nodule detection proportion estimates (DPE), and ROC analysis. RESULTS: For 135 nodules, detection rates for CAD and readers were 76.3, 52.6 and 52.6%, respectively; false-positive rates were 0.55, 0.25 and 0.15 per examination, respectively. In consensus with CAD the reader detection rate increased to 93.3%, and the false-positive rate dropped to 0.1/scan. DPEs for nodules ≤5 mm were significantly higher for ICAD than for the readers (p<0.05). Absence of vascular attachment was the only significant predictor of nodule detection by CAD (p=0.0006-0.008). There were no predictors of nodule detection for reader consensus with CAD. In contrast, vascular attachment predicted nodule detection by the readers (p=0.0001-0.003). Reader sensitivity was higher for nodules with vascular attachment than for unattached nodules (sensitivities 0.768 and 0.369; 95% confidence intervals=0.651-0.861 and 0.253-0.498, respectively). CONCLUSION: CAD increases nodule detection rates, decreases false-positive rates and compensates for deficient reader performance in detection of smallest lesions and of nodules without vascular attachment

  19. Standalone computer-aided detection compared to radiologists' performance for the detection of mammographic masses

    International Nuclear Information System (INIS)

    Hupse, Rianne; Samulski, Maurice; Imhof-Tas, Mechli W.; Karssemeijer, Nico; Lobbes, Marc; Boetes, Carla; Heeten, Ard den; Beijerinck, David; Pijnappel, Ruud

    2013-01-01

    We developed a computer-aided detection (CAD) system aimed at decision support for detection of malignant masses and architectural distortions in mammograms. The effect of this system on radiologists' performance depends strongly on its standalone performance. The purpose of this study was to compare the standalone performance of this CAD system to that of radiologists. In a retrospective study, nine certified screening radiologists and three residents read 200 digital screening mammograms without the use of CAD. Performances of the individual readers and of CAD were computed as the true-positive fraction (TPF) at a false-positive fraction of 0.05 and 0.2. Differences were analysed using an independent one-sample t-test. At a false-positive fraction of 0.05, the performance of CAD (TPF = 0.487) was similar to that of the certified screening radiologists (TPF = 0.518, P = 0.17). At a false-positive fraction of 0.2, CAD performance (TPF = 0.620) was significantly lower than the radiologist performance (TPF = 0.736, P <0.001). Compared to the residents, CAD performance was similar for all false-positive fractions. The sensitivity of CAD at a high specificity was comparable to that of human readers. These results show potential for CAD to be used as an independent reader in breast cancer screening. (orig.)

  20. Improving computer-aided detection assistance in breast cancer screening by removal of obviously false-positive findings

    NARCIS (Netherlands)

    Mordang, Jan-Jurre; Gubern-Merida, Albert; Bria, Alessandro; Tortorella, Francesco; den Heeten, Gerard; Karssemeijer, Nico

    2017-01-01

    Purpose: Computer-aided detection (CADe) systems for mammography screening still mark many false positives. This can cause radiologists to lose confidence in CADe, especially when many false positives are obviously not suspicious to them. In this study, we focus on obvious false positives generated

  1. Improving computer-aided detection assistance in breast cancer screening by removal of obviously false-positive findings

    NARCIS (Netherlands)

    Mordang, J.J.; Gubern Merida, A.; Bria, A.; Tortorella, F.; Heeten, G.; Karssemeijer, N.

    2017-01-01

    PURPOSE: Computer-aided detection (CADe) systems for mammography screening still mark many false positives. This can cause radiologists to lose confidence in CADe, especially when many false positives are obviously not suspicious to them. In this study, we focus on obvious false positives generated

  2. Computer-aided diagnosis workstation and network system for chest diagnosis based on multislice CT images

    Science.gov (United States)

    Satoh, Hitoshi; Niki, Noboru; Eguchi, Kenji; Moriyama, Noriyuki; Ohmatsu, Hironobu; Masuda, Hideo; Machida, Suguru

    2008-03-01

    Mass screening based on multi-helical CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. To overcome this problem, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images, a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification and a vertebra body analysis algorithm for quantitative evaluation of osteoporosis likelihood by using helical CT scanner for the lung cancer mass screening. The function to observe suspicious shadow in detail are provided in computer-aided diagnosis workstation with these screening algorithms. We also have developed the telemedicine network by using Web medical image conference system with the security improvement of images transmission, Biometric fingerprint authentication system and Biometric face authentication system. Biometric face authentication used on site of telemedicine makes "Encryption of file" and Success in login" effective. As a result, patients' private information is protected. Based on these diagnostic assistance methods, we have developed a new computer-aided workstation and a new telemedicine network that can display suspected lesions three-dimensionally in a short time. The results of this study indicate that our radiological information system without film by using computer-aided diagnosis workstation and our telemedicine network system can increase diagnostic speed, diagnostic accuracy and security improvement of medical information.

  3. Computer-aided detection and automated CT volumetry of pulmonary nodules

    International Nuclear Information System (INIS)

    Marten, Katharina; Engelke, Christoph

    2007-01-01

    With use of multislice computed tomography (MSCT), small pulmonary nodules are being detected in vast numbers, constituting the majority of all noncalcified lung nodules. Although the prevalence of lung cancers among such lesions in lung cancer screening populations is low, their isolation may contribute to increased patient survival. Computer-aided diagnosis (CAD) has emerged as a diverse set of diagnostic tools to handle the large number of images in MSCT datasets and most importantly, includes automated detection and volumetry of pulmonary nodules. Current CAD systems can significantly enhance experienced radiologists' performance and outweigh human limitations in identifying small lesions and manually measuring their diameters, augment observer consistency in the interpretation of such examinations and may thus help to detect significantly higher rates of early malignomas and give more precise estimates on chemotherapy response than can radiologists alone. In this review, we give an overview of current CAD in lung nodule detection and volumetry and discuss their relative merits and limitations. (orig.)

  4. Computer-aided safety systems of industrial high energy objects

    International Nuclear Information System (INIS)

    Topolsky, N.G.; Gordeev, S.G.

    1995-01-01

    Modern objects of fuel and energy, chemical industries are characterized by high power consumption; by presence of large quantities of combustible and explosive substances used in technological processes; by advanced communications of submission systems of initial liquid and gasiform reagents, lubricants and coolants, the products of processing, and wastes of production; by advanced ventilation and pneumatic transport; and by complex control systems of energy, material and information flows. Such objects have advanced infrastructures, including a significant quantity of engineering buildings intended for storage, transportation, and processing of combustible liquids, gasiform fuels and materials, and firm materials. Examples of similar objects are nuclear and thermal power stations, chemical plants, machine-building factories, iron and steel industry enterprises, etc. Many tasks and functions characterizing the problem of fire safety of these objects can be accomplished only upon the development of special Computer-Aided Fire Safety Systems (CAFSS). The CAFSS for these objects are intended to reduce the hazard of disastrous accidents both causing fires and caused by them. The tasks of fire prevention and rescue work of large-scale industrial objects are analyzed within the bounds of the recommended conception. A functional structure of CAFSS with a list of the main subsystems forming a part of its composition has been proposed

  5. Reproducibility of Computer-Aided Detection Marks in Digital Mammography

    International Nuclear Information System (INIS)

    Kim, Seung Ja; Moon, Woo Kyung; Cho, Nariya; Kim, Sun Mi; Im, Jung Gi; Cha, Joo Hee

    2007-01-01

    To evaluate the performance and reproducibility of a computeraided detection (CAD) system in mediolateral oblique (MLO) digital mammograms taken serially, without release of breast compression. A CAD system was applied preoperatively to the fulfilled digital mammograms of two MLO views taken without release of breast compression in 82 patients (age range: 33 83 years; mean age: 49 years) with previously diagnosed breast cancers. The total number of visible lesion components in 82 patients was 101: 66 masses and 35 microcalcifications. We analyzed the sensitivity and reproducibility of the CAD marks. The sensitivity of the CAD system for first MLO views was 71% (47/66) for masses and 80% (28/35) for microcalcifications. The sensitivity of the CAD system for second MLO views was 68% (45/66) for masses and 17% (6/35) for microcalcifications. In 84 ipsilateral serial MLO image sets (two patients had bilateral cancers), identical images, regardless of the existence of CAD marks, were obtained for 35% (29/84) and identical images with CAD marks were obtained for 29% (23/78). Identical images, regardless of the existence of CAD marks, for contralateral MLO images were 65% (52/80) and identical images with CAD marks were obtained for 28% (11/39). The reproducibility of CAD marks for the true positive masses in serial MLO views was 84% (42/50) and that for the true positive microcalcifications was 0% (0/34). The CAD system in digital mammograms showed a high sensitivity for detecting masses and microcalcifications. However, reproducibility of microcalcification marks was very low in MLO views taken serially without release of breast compression. Minute positional change and patient movement can alter the images and result in a significant effect on the algorithm utilized by the CAD for detecting microcalcifications

  6. Computer-aided Detection of Lung Cancer on Chest Radiographs: Effect on Observer Performance

    NARCIS (Netherlands)

    de Hoop, Bartjan; de Boo, Diederik W.; Gietema, Hester A.; van Hoorn, Frans; Mearadji, Banafsche; Schijf, Laura; van Ginneken, Bram; Prokop, Mathias; Schaefer-Prokop, Cornelia

    2010-01-01

    Purpose: To assess how computer-aided detection (CAD) affects reader performance in detecting early lung cancer on chest radiographs. Materials and Methods: In this ethics committee-approved study, 46 individuals with 49 computed tomographically (CT)-detected and histologically proved lung cancers

  7. Computer-aided-detection marker value and breast density in the detection of invasive lobular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Destounis, Stamatia; Hanson, Sarah [The Elizabeth Wende Breast Clinic, Rochester, NY (United States); Roehrig, Jimmy [R2/Hologic, Inc., Santa Clara, CA (United States)

    2007-08-15

    Invasive Lobular Carcinoma (ILC) is frequently a mammographic and diagnostic dilemma; thus any additional information that CAD (Computer-Aided Detection) systems can give radiologists may be helpful. Our study was to evaluate the role of CAD numeric values as indicators of malignancy and the effect of breast density in the diagnosis of ILC. Eighty consecutive biopsy-proven ILC cases with CAD (ImageChecker {sup registered}, Hologic vertical stroke R2, Santa Clara, CA, versions 2.3, 3.1, 3.2, 5.0, 5.2) diagnosed between June 2002 and December 2004 were retrospectively reviewed. Data included: BIRADS {sup registered} breast density, whether CAD marked the cancer at diagnosis year or years prior, and lesion type. Study mammograms underwent additional CAD scans (Image Checker {sup registered} V5.3, V8.0, V8.1) to obtain a numeric value associated with each marker, low values represent increasingly suspicious features. CAD correctly marked 65% (52/80) of ILC cases, detection was found to decrease with increased breast density. Numeric values of CAD marks at sites of carcinoma showed median score of 171 (range 0 - 1121). The CAD marker may potentially be used as an additional indicator of suspicious lesion features in all breast densities and higher likelihood that an area on the mammogram requires further investigation. (orig.)

  8. Computer-aided-detection marker value and breast density in the detection of invasive lobular carcinoma

    International Nuclear Information System (INIS)

    Destounis, Stamatia; Hanson, Sarah; Roehrig, Jimmy

    2007-01-01

    Invasive Lobular Carcinoma (ILC) is frequently a mammographic and diagnostic dilemma; thus any additional information that CAD (Computer-Aided Detection) systems can give radiologists may be helpful. Our study was to evaluate the role of CAD numeric values as indicators of malignancy and the effect of breast density in the diagnosis of ILC. Eighty consecutive biopsy-proven ILC cases with CAD (ImageChecker registered , Hologic vertical stroke R2, Santa Clara, CA, versions 2.3, 3.1, 3.2, 5.0, 5.2) diagnosed between June 2002 and December 2004 were retrospectively reviewed. Data included: BIRADS registered breast density, whether CAD marked the cancer at diagnosis year or years prior, and lesion type. Study mammograms underwent additional CAD scans (Image Checker registered V5.3, V8.0, V8.1) to obtain a numeric value associated with each marker, low values represent increasingly suspicious features. CAD correctly marked 65% (52/80) of ILC cases, detection was found to decrease with increased breast density. Numeric values of CAD marks at sites of carcinoma showed median score of 171 (range 0 - 1121). The CAD marker may potentially be used as an additional indicator of suspicious lesion features in all breast densities and higher likelihood that an area on the mammogram requires further investigation. (orig.)

  9. CAISSE (Computer Aided Information System on Solar Energy) technical manual

    Energy Technology Data Exchange (ETDEWEB)

    Cantelon, P E; Beinhauer, F W

    1979-01-01

    The Computer Aided Information System on Solar Energy (CAISSE) was developed to provide the general public with information on solar energy and its potential uses and costs for domestic consumption. CAISSE is an interactive computing system which illustrates solar heating concepts through the use of 35 mm slides, text displays on a screen and a printed report. The user communicates with the computer by responding to questions about his home and heating requirements through a touch sensitive screen. The CAISSE system contains a solar heating simulation model which calculates the heating load capable of being supplied by a solar heating system and uses this information to illustrate installation costs, fuel savings and a 20 year life-cycle analysis of cost and benefits. The system contains several sets of radiation and weather data for Canada and USA. The selection of one of four collector models is based upon the requirements input during the computer session. Optimistic and pessimistic fuel cost forecasts are made for oil, natural gas, electricity, or propane; and the forecasted fuel cost is made the basis of the life cycle cost evaluation for the solar heating application chosen. This manual is organized so that each section describes one major aspect of the use of solar energy systems to provide energy for domestic consumption. The sources of data and technical information and the method of incorporating them into the CAISSE display system are described in the same order as the computer processing. Each section concludes with a list of future developments that could be included to make CAISSE outputs more regionally specific and more useful to designers. 19 refs., 1 tab.

  10. Computer-aided detection of basal cell carcinoma through blood content analysis in dermoscopy images

    Science.gov (United States)

    Kharazmi, Pegah; Kalia, Sunil; Lui, Harvey; Wang, Z. Jane; Lee, Tim K.

    2018-02-01

    Basal cell carcinoma (BCC) is the most common type of skin cancer, which is highly damaging to the skin at its advanced stages and causes huge costs on the healthcare system. However, most types of BCC are easily curable if detected at early stage. Due to limited access to dermatologists and expert physicians, non-invasive computer-aided diagnosis is a viable option for skin cancer screening. A clinical biomarker of cancerous tumors is increased vascularization and excess blood flow. In this paper, we present a computer-aided technique to differentiate cancerous skin tumors from benign lesions based on vascular characteristics of the lesions. Dermoscopy image of the lesion is first decomposed using independent component analysis of the RGB channels to derive melanin and hemoglobin maps. A novel set of clinically inspired features and ratiometric measurements are then extracted from each map to characterize the vascular properties and blood content of the lesion. The feature set is then fed into a random forest classifier. Over a dataset of 664 skin lesions, the proposed method achieved an area under ROC curve of 0.832 in a 10-fold cross validation for differentiating basal cell carcinomas from benign lesions.

  11. Computer aided instrumented Charpy test applied dynamic fracture toughness evaluation system

    International Nuclear Information System (INIS)

    Kobayashi, Toshiro; Niinomi, Mitsuo

    1986-01-01

    Micro computer aided data treatment system and personal computer aided data analysis system were applied to the traditional instrumented Charpy impact test system. The analysis of Charpy absorbed energy (E i , E p , E t ) and load (P y , P m ), and the evaluation of dynamic toughness through whole fracture process, i.e. J Id , J R curve and T mat was examined using newly developed computer aided instrumented Charpy impact test system. E i , E p , E t , P y and P m were effectively analyzed using moving average method and printed out automatically by micro computer aided data treatment system. J Id , J R curve and T mat could be measured by stop block test method. Then, J Id , J R curve and T mat were effectively estimated using compliance changing rate method and key curve method on the load-load point displacement curve of single fatigue cracked specimen by personal computer aided data analysis system. (author)

  12. Observer training for computer-aided detection of pulmonary nodules in chest radiography

    NARCIS (Netherlands)

    de Boo, Diederick W.; van Hoorn, François; van Schuppen, Joost; Schijf, Laura; Scheerder, Maeke J.; Freling, Nicole J.; Mets, Onno; Weber, Michael; Schaefer-Prokop, Cornelia M.

    2012-01-01

    To assess whether short-term feedback helps readers to increase their performance using computer-aided detection (CAD) for nodule detection in chest radiography. The 140 CXRs (56 with a solitary CT-proven nodules and 84 negative controls) were divided into four subsets of 35; each were read in a

  13. Computer-Aided Diagnosis Systems for Brain Diseases in Magnetic Resonance Images

    Directory of Open Access Journals (Sweden)

    Yasuo Yamashita

    2009-07-01

    Full Text Available This paper reviews the basics and recent researches of computer-aided diagnosis (CAD systems for assisting neuroradiologists in detection of brain diseases, e.g., asymptomatic unruptured aneurysms, Alzheimer's disease, vascular dementia, and multiple sclerosis (MS, in magnetic resonance (MR images. The CAD systems consist of image feature extraction based on image processing techniques and machine learning classifiers such as linear discriminant analysis, artificial neural networks, and support vector machines. We introduce useful examples of the CAD systems in the neuroradiology, and conclude with possibilities in the future of the CAD systems for brain diseases in MR images.

  14. [Development of a Computer-aided Diagnosis System to Distinguish between Benign and Malignant Mammary Tumors in Dynamic Magnetic Resonance Images: Automatic Detection of the Position with the Strongest Washout Effect in the Tumor].

    Science.gov (United States)

    Miyazaki, Yoshiaki; Tabata, Nobuyuki; Taroura, Tomomi; Shinozaki, Kenji; Kubo, Yuichiro; Tokunaga, Eriko; Taguchi, Kenichi

    We propose a computer-aided diagnostic (CAD) system that uses time-intensity curves to distinguish between benign and malignant mammary tumors. Many malignant tumors show a washout pattern in time-intensity curves. Therefore, we designed a program that automatically detects the position with the strongest washout effect using the technique, such as the subtraction technique, which extracts only the washout area in the tumor, and by scanning data in 2×2 pixel region of interest (ROI). Operation of this independently developed program was verified using a phantom system that simulated tumors. In three cases of malignant tumors, the washout pattern detection rate in images with manually set ROI was ≤6%, whereas the detection rate with our novel method was 100%. In one case of a benign tumor, when the same method was used, we checked that there was no washout effect and detected the persistent pattern. Thus, the distinction between benign and malignant tumors using our method was completely consistent with the pathological diagnoses made. Our novel method is therefore effective for differentiating between benign and malignant mammary tumors in dynamic magnetic resonance images.

  15. Computer-aided detection of breast carcinoma in standard mammographic projections with digital mammography

    International Nuclear Information System (INIS)

    Destounis, S.; Hanson, S.

    2007-01-01

    This study was conducted to retrospectively evaluate a computer-aided detection system's ability to detect breast carcinoma in multiple standard mammographic projections. Forty-five lesions in 44 patients imaged with digital mammography (Selenia registered , Hologic, Bedford, MA; Senographe registered , GE, Milwaukee, WI) and had computer-aided detection (CAD, Image-checker registered V 8.3.15, Hologic/R2, Santa Clara, CA) applied at the time of examination were identified for review; all were subsequently recommended to biopsy where cancer was revealed. These lesions were determined by the study Radiologist to be visible in both standard mammographic images (mediolateral oblique, MLO; craniocaudal, CC). For each patient, case data included patient age, tissue density, lesion type, BIRADS registered assessment, lesion size, lesion visibility-visible on MLO and/or CC view, ability of CAD to correctly mark the cancerous lesion, number of CAD marks per image, needle core biopsy results and surgical pathologic correlation. For this study cohort. CAD lesion/case sensitivity of 87% (n = 39) was found and image sensitivity was found to be 69% (n = 31) for MLO view and 78% (n = 35) for the CC view. For the study cohort, cases presented with a median of four marks per cases (range 0-13). Eighty-four percent (n = 38) of lesions proceeded to excision; initial needle biopsy pathology was upgraded at surgical excision from in situ disease to invasive for 24% (n = 9) lesions. CAD has demonstrated the potential to detect mammographically visible cancers in multiple standard mammographic projections in all categories of lesions in this study cohort. (orig.)

  16. Micrometric precision of prosthetic dental crowns obtained by optical scanning and computer-aided designing/computer-aided manufacturing system

    Science.gov (United States)

    das Neves, Flávio Domingues; de Almeida Prado Naves Carneiro, Thiago; do Prado, Célio Jesus; Prudente, Marcel Santana; Zancopé, Karla; Davi, Letícia Resende; Mendonça, Gustavo; Soares, Carlos José

    2014-08-01

    The current study evaluated prosthetic dental crowns obtained by optical scanning and a computer-aided designing/computer-aided manufacturing system using micro-computed tomography to compare the marginal fit. The virtual models were obtained with four different scanning surfaces: typodont (T), regular impressions (RI), master casts (MC), and powdered master casts (PMC). Five virtual models were obtained for each group. For each model, a crown was designed on the software and milled from feldspathic ceramic blocks. Micro-CT images were obtained for marginal gap measurements and the data were statistically analyzed by one-way analysis of variance followed by Tukey's test. The mean vertical misfit was T=62.6±65.2 μm; MC=60.4±38.4 μm; PMC=58.1±38.0 μm, and RI=89.8±62.8 μm. Considering a percentage of vertical marginal gap of up to 75 μm, the results were T=71.5%, RI=49.2%, MC=69.6%, and PMC=71.2%. The percentages of horizontal overextension were T=8.5%, RI=0%, MC=0.8%, and PMC=3.8%. Based on the results, virtual model acquisition by scanning the typodont (simulated mouth) or MC, with or without powder, showed acceptable values for the marginal gap. The higher result of marginal gap of the RI group suggests that it is preferable to scan this directly from the mouth or from MC.

  17. Digital mammography: Signal-extraction strategies for computer-aided detection of microcalcifications

    International Nuclear Information System (INIS)

    Chan, H.P.; Doi, K.; Metz, C.E.; Vyborny, C.J.; Lam, K.L.; Schmidt, R.A.

    1987-01-01

    The authors found that the structured background of a mammogram can be removed effectively by either a difference-image technique (using a matched filter in combination with a median filter, a contrast-reversal filter, or a box-rim filter) or a visual response filter alone. Locally adaptive gray-level thresholding and region-growing techniques can then be employed to extract microcalcifications from the processed image. Signals are further distinguished from noise or artifacts by their size, contrast, and clustering properties. The authors studied the dependence of the detectability of microcalcifications on the various signal-extraction strategies. Potential application of the computer-aided system to mammography is assessed by its performance on clinical mammograms

  18. Computer Aided Detection of Breast Masses in Digital Tomosynthesis

    Science.gov (United States)

    2008-06-01

    of unknown pathology , all other ROIs generated from that specific subject’s reconstructed volumes were excluded from the KB. For scheme B, all the FPs...query ROI of unknown pathology , all other ROIs generated from that specific subject’s reconstructed volumes were excluded from the KB. For scheme B...Qian, L. Li, and L.P. Clarke, "Image feature extraction for mass detection in digital mammography: Influence of wavelet analysis." Med. Phys. 26

  19. Computer-aided detection (CAD) in mammography: Does it help the junior or the senior radiologist?

    International Nuclear Information System (INIS)

    Balleyguier, Corinne; Kinkel, Karen; Fermanian, Jacques; Malan, Sebastien; Djen, Germaine; Taourel, Patrice; Helenon, Olivier

    2005-01-01

    Objectives: To evaluate the impact of a computer-aided detection (CAD) system on the ability of a junior and senior radiologist to detect breast cancers on mammograms, and to determine the potential of CAD as a teaching tool in mammography. Methods: Hundred biopsy-proven cancers and 100 normal mammograms were randomly analyzed by a CAD system. The sensitivity (Se) and specificity (Sp) of the CAD system were calculated. In the second phase, to simulate daily practice, 110 mammograms (97 normal or with benign lesions, and 13 cancers) were examined independently by a junior and a senior radiologist, with and without CAD. Interpretations were standardized according to BI-RADS classification. Sensitivity, Specificity, positive and negative predictive values (PPV, NPV) were calculated for each session. Results: For the senior radiologist, Se slightly improved from 76.9 to 84.6% after CAD analysis (NS) (one case of clustered microcalcifications case overlooked by the senior radiologist was detected by CAD). Sp, PPV and PNV did not change significantly. For the junior radiologist, Se improved from 61.9 to 84.6% (significant change). Three cancers overlooked by the junior radiologist were detected by CAD. Sp was unchanged. Conclusion: CAD mammography proved more useful for the junior than for the senior radiologist, improving sensitivity. The CAD system may represent a useful educational tool for mammography

  20. Multiple-instance learning for computer-aided detection of tuberculosis

    Science.gov (United States)

    Melendez, J.; Sánchez, C. I.; Philipsen, R. H. H. M.; Maduskar, P.; van Ginneken, B.

    2014-03-01

    Detection of tuberculosis (TB) on chest radiographs (CXRs) is a hard problem. Therefore, to help radiologists or even take their place when they are not available, computer-aided detection (CAD) systems are being developed. In order to reach a performance comparable to that of human experts, the pattern recognition algorithms of these systems are typically trained on large CXR databases that have been manually annotated to indicate the abnormal lung regions. However, manually outlining those regions constitutes a time-consuming process that, besides, is prone to inconsistencies and errors introduced by interobserver variability and the absence of an external reference standard. In this paper, we investigate an alternative pattern classi cation method, namely multiple-instance learning (MIL), that does not require such detailed information for a CAD system to be trained. We have applied this alternative approach to a CAD system aimed at detecting textural lesions associated with TB. Only the case (or image) condition (normal or abnormal) was provided in the training stage. We compared the resulting performance with those achieved by several variations of a conventional system trained with detailed annotations. A database of 917 CXRs was constructed for experimentation. It was divided into two roughly equal parts that were used as training and test sets. The area under the receiver operating characteristic curve was utilized as a performance measure. Our experiments show that, by applying the investigated MIL approach, comparable results as with the aforementioned conventional systems are obtained in most cases, without requiring condition information at the lesion level.

  1. Computer-aided system for fire fighting in an underground mine

    Energy Technology Data Exchange (ETDEWEB)

    Rosiek, F; Sikora, M; Urbanski, J [Politechnika Wroclawska (Poland). Instytut Gornictwa

    1989-01-01

    Discusses structure of an algorithm for computer-aided planning of fire fighting and rescue in an underground coal mine. The algorithm developed by the Mining Institute of the Wroclaw Technical University consists of ten options: regulations on fire fighting, fire alarm for miners working underground (rescue ways, fire zones etc.), information system for mine management, movements of fire fighting teams, distribution of fire fighting equipment, assessment of explosion hazards of fire gases, fire gas temperature control of blower operation, detection of endogenous fires, ventilation control. 2 refs.

  2. A ROC-based feature selection method for computer-aided detection and diagnosis

    Science.gov (United States)

    Wang, Songyuan; Zhang, Guopeng; Liao, Qimei; Zhang, Junying; Jiao, Chun; Lu, Hongbing

    2014-03-01

    Image-based computer-aided detection and diagnosis (CAD) has been a very active research topic aiming to assist physicians to detect lesions and distinguish them from benign to malignant. However, the datasets fed into a classifier usually suffer from small number of samples, as well as significantly less samples available in one class (have a disease) than the other, resulting in the classifier's suboptimal performance. How to identifying the most characterizing features of the observed data for lesion detection is critical to improve the sensitivity and minimize false positives of a CAD system. In this study, we propose a novel feature selection method mR-FAST that combines the minimal-redundancymaximal relevance (mRMR) framework with a selection metric FAST (feature assessment by sliding thresholds) based on the area under a ROC curve (AUC) generated on optimal simple linear discriminants. With three feature datasets extracted from CAD systems for colon polyps and bladder cancer, we show that the space of candidate features selected by mR-FAST is more characterizing for lesion detection with higher AUC, enabling to find a compact subset of superior features at low cost.

  3. Development of the computer-aided process planning (CAPP system for polymer injection molds manufacturing

    Directory of Open Access Journals (Sweden)

    J. Tepić

    2011-10-01

    Full Text Available Beginning of production and selling of polymer products largely depends on mold manufacturing. The costs of mold manufacturing have significant share in the final price of a product. The best way to improve and rationalize polymer injection molds production process is by doing mold design automation and manufacturing process planning automation. This paper reviews development of a dedicated process planning system for manufacturing of the mold for injection molding, which integrates computer-aided design (CAD, computer-aided process planning (CAPP and computer-aided manufacturing (CAM technologies.

  4. Computer-Aided Prototyping Systems (CAPS) within the software acquisition process: a case study

    OpenAIRE

    Ellis, Mary Kay

    1993-01-01

    Approved for public release; distribution is unlimited This thesis provides a case study which examines the benefits derived from the practice of computer-aided prototyping within the software acquisition process. An experimental prototyping systems currently in research is the Computer Aided Prototyping System (CAPS) managed under the Computer Science department of the Naval Postgraduate School, Monterey, California. This thesis determines the qualitative value which may be realized by ...

  5. Deep learning of contrast-coated serrated polyps for computer-aided detection in CT colonography

    Science.gov (United States)

    Näppi, Janne J.; Pickhardt, Perry; Kim, David H.; Hironaka, Toru; Yoshida, Hiroyuki

    2017-03-01

    Serrated polyps were previously believed to be benign lesions with no cancer potential. However, recent studies have revealed a novel molecular pathway where also serrated polyps can develop into colorectal cancer. CT colonography (CTC) can detect serrated polyps using the radiomic biomarker of contrast coating, but this requires expertise from the reader and current computer-aided detection (CADe) systems have not been designed to detect the contrast coating. The purpose of this study was to develop a novel CADe method that makes use of deep learning to detect serrated polyps based on their contrast-coating biomarker in CTC. In the method, volumetric shape-based features are used to detect polyp sites over soft-tissue and fecal-tagging surfaces of the colon. The detected sites are imaged using multi-angular 2D image patches. A deep convolutional neural network (DCNN) is used to review the image patches for the presence of polyps. The DCNN-based polyp-likelihood estimates are merged into an aggregate likelihood index where highest values indicate the presence of a polyp. For pilot evaluation, the proposed DCNN-CADe method was evaluated with a 10-fold cross-validation scheme using 101 colonoscopy-confirmed cases with 144 biopsy-confirmed serrated polyps from a CTC screening program, where the patients had been prepared for CTC with saline laxative and fecal tagging by barium and iodine-based diatrizoate. The average per-polyp sensitivity for serrated polyps >=6 mm in size was 93+/-7% at 0:8+/-1:8 false positives per patient on average. The detection accuracy was substantially higher that of a conventional CADe system. Our results indicate that serrated polyps can be detected automatically at high accuracy in CTC.

  6. Computer-Aided Detection of Malignant Lung Nodules on Chest Radiographs: Effect on Observers' Performance

    International Nuclear Information System (INIS)

    Lee, Kyung Hee; Goo, Jin Mo; Park, Chang Min; Lee, Hyun Ju; Jin, Kwang Nam

    2012-01-01

    To evaluate the effect of computer-aided detection (CAD) system on observer performance in the detection of malignant lung nodules on chest radiograph. Two hundred chest radiographs (100 normal and 100 abnormal with malignant solitary lung nodules) were evaluated. With CT and histological confirmation serving as a reference, the mean nodule size was 15.4 mm (range, 7-20 mm). Five chest radiologists and five radiology residents independently interpreted both the original radiographs and CAD output images using the sequential testing method. The performances of the observers for the detection of malignant nodules with and without CAD were compared using the jackknife free-response receiver operating characteristic analysis. Fifty-nine nodules were detected by the CAD system with a false positive rate of 1.9 nodules per case. The detection of malignant lung nodules significantly increased from 0.90 to 0.92 for a group of observers, excluding one first-year resident (p = 0.04). When lowering the confidence score was not allowed, the average figure of merit also increased from 0.90 to 0.91 (p = 0.04) for all observers after a CAD review. On average, the sensitivities with and without CAD were 87% and 84%, respectively; the false positive rates per case with and without CAD were 0.19 and 0.17, respectively. The number of additional malignancies detected following true positive CAD marks ranged from zero to seven for the various observers. The CAD system may help improve observer performance in detecting malignant lung nodules on chest radiographs and contribute to a decrease in missed lung cancer.

  7. Computer-aided detection (CAD) of lung nodules and small tumours on chest radiographs

    International Nuclear Information System (INIS)

    De Boo, D.W.; Prokop, M.; Uffmann, M.; Ginneken, B. van; Schaefer-Prokop, C.M.

    2009-01-01

    Detection of focal pulmonary lesions is limited by quantum and anatomic noise and highly influenced by variable perception capacity of the reader. Multiple studies have proven that lesions - missed at time of primary interpretation - were visible on the chest radiographs in retrospect. Computer-aided diagnosis (CAD) schemes do not alter the anatomic noise but aim at decreasing the intrinsic limitations and variations of human perception by alerting the reader to suspicious areas in a chest radiograph when used as a 'second reader'. Multiple studies have shown that the detection performance can be improved using CAD especially for less experienced readers at a variable amount of decreased specificity. There seem to be a substantial learning process for both, experienced and inexperienced readers, to be able to optimally differentiate between false positive and true positive lesions and to build up sufficient trust in the capabilities of these systems to be able to use them at their full advantage. Studies so far focussed on stand-alone performance of the CAD schemes to reveal the magnitude of potential impact or on retrospective evaluation of CAD as a second reader for selected study groups. Further research is needed to assess the performance of these systems in clinical routine and to determine the trade-off between performance increase in terms of increased sensitivity and decreased inter-reader variability and loss of specificity and secondary indicated follow-up examinations for further diagnostic workup.

  8. Reproducibility of prompts in computer-aided detection (CAD) of breast cancer

    International Nuclear Information System (INIS)

    Taylor, C.G.; Champness, J.; Reddy, M.; Taylor, P.; Potts, H.W.W.; Given-Wilson, R.

    2003-01-01

    AIM: We evaluated the reproducibility of prompts using the R2 ImageChecker M2000 computer-aided detection (CAD) system. MATERIALS AND METHODS: Forty selected two-view mammograms of women with breast cancer were digitized and analysed using the ImageChecker on 10 separate occasions. The mammograms were chosen to provide both straightforward and subtle signs of malignancy. Data analysed included mammographic abnormality, pathology, and whether the cancer was prompted or given an emphasized prompt. RESULTS: Correct prompts were generated in 86 out of 100 occasions for screen-detected cancers. Reproducibility was less in the other categories of more subtle cancers: 21% for cancers previously missed by CAD, a group that contained more grade 1 and small (<10 mm) tumours. Prompts for calcifications were more reproducible than those for masses (76% versus 53%) and these cancers were more likely to have an emphasized prompt. CONCLUSIONS: Probably the most important cause of variability of prompts is shifts in film position between sequential digitizations. Consequently subtle lesions that are only just above the threshold for display may not be prompted on repeat scanning. However, users of CAD should be aware that even emphasized prompts are not consistently reproducible

  9. Computer aided detection of brain micro-bleeds in traumatic brain injury

    Science.gov (United States)

    van den Heuvel, T. L. A.; Ghafoorian, M.; van der Eerden, A. W.; Goraj, B. M.; Andriessen, T. M. J. C.; ter Haar Romeny, B. M.; Platel, B.

    2015-03-01

    Brain micro-bleeds (BMBs) are used as surrogate markers for detecting diffuse axonal injury in traumatic brain injury (TBI) patients. The location and number of BMBs have been shown to influence the long-term outcome of TBI. To further study the importance of BMBs for prognosis, accurate localization and quantification are required. The task of annotating BMBs is laborious, complex and prone to error, resulting in a high inter- and intra-reader variability. In this paper we propose a computer-aided detection (CAD) system to automatically detect BMBs in MRI scans of moderate to severe neuro-trauma patients. Our method consists of four steps. Step one: preprocessing of the data. Both susceptibility (SWI) and T1 weighted MRI scans are used. The images are co-registered, a brain-mask is generated, the bias field is corrected, and the image intensities are normalized. Step two: initial candidates for BMBs are selected as local minima in the processed SWI scans. Step three: feature extraction. BMBs appear as round or ovoid signal hypo-intensities on SWI. Twelve features are computed to capture these properties of a BMB. Step four: Classification. To identify BMBs from the set of local minima using their features, different classifiers are trained on a database of 33 expert annotated scans and 18 healthy subjects with no BMBs. Our system uses a leave-one-out strategy to analyze its performance. With a sensitivity of 90% and 1.3 false positives per BMB, our CAD system shows superior results compared to state-of-the-art BMB detection algorithms (developed for non-trauma patients).

  10. Computer-aided detection of lung nodules in digital chest radiographs

    International Nuclear Information System (INIS)

    Giger, M.L.; Doi, K.; MacMahon, H.M.

    1986-01-01

    The authors are developing an automated method to detect lung nodules by eliminating the ''camouflaging: effect of the lung background. In order to increase the conspicuity of the nodules, we created, from a single chest radiograph, two images: one in which the signal-to-noise ratio (S/N) of the nodule is maximized and another in which that S/N is suppressed. The difference between these two processed images was subjected to feature-extraction technique in order to isolate the nodules. The detection accuracy of the computer-aided detection scheme, as compared with unaided radiologists' performance, was determined using receiver operating characteristic curve analysis

  11. Use of logic flowgraph models in a computer aided process analysis and management system

    International Nuclear Information System (INIS)

    Guarro, S.B.; Okrent, D.

    1985-07-01

    The development of a multi-function computer-aided process analysis and management (CAPAM) system, to be implemented in nuclear power plant control rooms, is proposed and discussed. The design goals identified for such a system are early disturbance detection and diagnosis, accompanied by identification of the best possible recovery actions or alternative success paths. The CAPAM structure is articulated in three functional levels with dedicated CRT displays. Increasing amount of diagnostic or recovery information is made available to the operators at the lower display levels. Probabilistic safety margins to the loss of important safety functions may be also calculated. The proposed implementation of the CAPAM concept is based on the use of logic flowgraph networks for the more detailed system modeling. Examples of such an implementation are given. 7 refs., 3 figs., 2 tabs

  12. Evaluation of a computer aided X-ray fluorographic system: part 1 - system analysis

    International Nuclear Information System (INIS)

    Burch, S.F.; Cocking, S.J.

    1982-02-01

    A computer aided, X-ray fluorographic (CAF) system has been assembled for application in non-destructive testing. The fluorographic hardware comprises a rare earth phosphor viewed with a low-light level SIT (Silicon intensifier target) TV camera, suitable for real time imaging in an industrial environment. A digital image processor allows integration to reduce noise and hence increase the thickness sensitivity. It also provides image modification for optimum visual detection of defects. Measurements of the resolution of the system and the noise on the fluorographic images are presented. Observations of wire type IQIs gave subjective thickness sensitivities of 2 to 4% for steel specimens up to 9mm thick. The observed noise was caused primarily by the camera rather than by the fundamental limit expected from X-ray photon statistics. The present system has, in practical applications, shown a capability to detect small (0.5mm) volumetric defects in castings. Further developments of the system are also discussed. It is concluded that a micro-focus X-ray set should be used with the existing hardware to investigate projection magnification fluoroscopy. (author)

  13. Computer-aided detection of masses in digital tomosynthesis mammography: Comparison of three approaches

    International Nuclear Information System (INIS)

    Chan Heangping; Wei Jun; Zhang Yiheng; Helvie, Mark A.; Moore, Richard H.; Sahiner, Berkman; Hadjiiski, Lubomir; Kopans, Daniel B.

    2008-01-01

    The authors are developing a computer-aided detection (CAD) system for masses on digital breast tomosynthesis mammograms (DBT). Three approaches were evaluated in this study. In the first approach, mass candidate identification and feature analysis are performed in the reconstructed three-dimensional (3D) DBT volume. A mass likelihood score is estimated for each mass candidate using a linear discriminant analysis (LDA) classifier. Mass detection is determined by a decision threshold applied to the mass likelihood score. A free response receiver operating characteristic (FROC) curve that describes the detection sensitivity as a function of the number of false positives (FPs) per breast is generated by varying the decision threshold over a range. In the second approach, prescreening of mass candidate and feature analysis are first performed on the individual two-dimensional (2D) projection view (PV) images. A mass likelihood score is estimated for each mass candidate using an LDA classifier trained for the 2D features. The mass likelihood images derived from the PVs are backprojected to the breast volume to estimate the 3D spatial distribution of the mass likelihood scores. The FROC curve for mass detection can again be generated by varying the decision threshold on the 3D mass likelihood scores merged by backprojection. In the third approach, the mass likelihood scores estimated by the 3D and 2D approaches, described above, at the corresponding 3D location are combined and evaluated using FROC analysis. A data set of 100 DBT cases acquired with a GE prototype system at the Breast Imaging Laboratory in the Massachusetts General Hospital was used for comparison of the three approaches. The LDA classifiers with stepwise feature selection were designed with leave-one-case-out resampling. In FROC analysis, the CAD system for detection in the DBT volume alone achieved test sensitivities of 80% and 90% at average FP rates of 1.94 and 3.40 per breast, respectively. With the

  14. Computer-aided detection of brain metastasis on 3D MR imaging: Observer performance study.

    Directory of Open Access Journals (Sweden)

    Leonard Sunwoo

    Full Text Available To assess the effect of computer-aided detection (CAD of brain metastasis (BM on radiologists' diagnostic performance in interpreting three-dimensional brain magnetic resonance (MR imaging using follow-up imaging and consensus as the reference standard.The institutional review board approved this retrospective study. The study cohort consisted of 110 consecutive patients with BM and 30 patients without BM. The training data set included MR images of 80 patients with 450 BM nodules. The test set included MR images of 30 patients with 134 BM nodules and 30 patients without BM. We developed a CAD system for BM detection using template-matching and K-means clustering algorithms for candidate detection and an artificial neural network for false-positive reduction. Four reviewers (two neuroradiologists and two radiology residents interpreted the test set images before and after the use of CAD in a sequential manner. The sensitivity, false positive (FP per case, and reading time were analyzed. A jackknife free-response receiver operating characteristic (JAFROC method was used to determine the improvement in the diagnostic accuracy.The sensitivity of CAD was 87.3% with an FP per case of 302.4. CAD significantly improved the diagnostic performance of the four reviewers with a figure-of-merit (FOM of 0.874 (without CAD vs. 0.898 (with CAD according to JAFROC analysis (p < 0.01. Statistically significant improvement was noted only for less-experienced reviewers (FOM without vs. with CAD, 0.834 vs. 0.877, p < 0.01. The additional time required to review the CAD results was approximately 72 sec (40% of the total review time.CAD as a second reader helps radiologists improve their diagnostic performance in the detection of BM on MR imaging, particularly for less-experienced reviewers.

  15. Computer-aided detection of brain metastasis on 3D MR imaging: Observer performance study.

    Science.gov (United States)

    Sunwoo, Leonard; Kim, Young Jae; Choi, Seung Hong; Kim, Kwang-Gi; Kang, Ji Hee; Kang, Yeonah; Bae, Yun Jung; Yoo, Roh-Eul; Kim, Jihang; Lee, Kyong Joon; Lee, Seung Hyun; Choi, Byung Se; Jung, Cheolkyu; Sohn, Chul-Ho; Kim, Jae Hyoung

    2017-01-01

    To assess the effect of computer-aided detection (CAD) of brain metastasis (BM) on radiologists' diagnostic performance in interpreting three-dimensional brain magnetic resonance (MR) imaging using follow-up imaging and consensus as the reference standard. The institutional review board approved this retrospective study. The study cohort consisted of 110 consecutive patients with BM and 30 patients without BM. The training data set included MR images of 80 patients with 450 BM nodules. The test set included MR images of 30 patients with 134 BM nodules and 30 patients without BM. We developed a CAD system for BM detection using template-matching and K-means clustering algorithms for candidate detection and an artificial neural network for false-positive reduction. Four reviewers (two neuroradiologists and two radiology residents) interpreted the test set images before and after the use of CAD in a sequential manner. The sensitivity, false positive (FP) per case, and reading time were analyzed. A jackknife free-response receiver operating characteristic (JAFROC) method was used to determine the improvement in the diagnostic accuracy. The sensitivity of CAD was 87.3% with an FP per case of 302.4. CAD significantly improved the diagnostic performance of the four reviewers with a figure-of-merit (FOM) of 0.874 (without CAD) vs. 0.898 (with CAD) according to JAFROC analysis (p reviewers (FOM without vs. with CAD, 0.834 vs. 0.877, p review the CAD results was approximately 72 sec (40% of the total review time). CAD as a second reader helps radiologists improve their diagnostic performance in the detection of BM on MR imaging, particularly for less-experienced reviewers.

  16. Computer-aided detection of bladder wall thickening in CT urography (CTU)

    Science.gov (United States)

    Cha, Kenny H.; Hadjiiski, Lubomir M.; Chan, Heang-Ping; Caoili, Elaine M.; Cohan, Richard H.; Weizer, Alon Z.; Gordon, Marshall N.; Samala, Ravi K.

    2018-02-01

    We are developing a computer-aided detection system for bladder cancer in CT urography (CTU). Bladder wall thickening is a manifestation of bladder cancer and its detection is more challenging than the detection of bladder masses. We first segmented the inner and outer bladder walls using our method that combined deep-learning convolutional neural network with level sets. The non-contrast-enhanced region was separated from the contrast-enhanced region with a maximum-intensity-projection-based method. The non-contrast region was smoothed and gray level threshold was applied to the contrast and non-contrast regions separately to extract the bladder wall and potential lesions. The bladder wall was transformed into a straightened thickness profile, which was analyzed to identify regions of wall thickening candidates. Volume-based features of the wall thickening candidates were analyzed with linear discriminant analysis (LDA) to differentiate bladder wall thickenings from false positives. A data set of 112 patients, 87 with wall thickening and 25 with normal bladders, was collected retrospectively with IRB approval, and split into independent training and test sets. Of the 57 training cases, 44 had bladder wall thickening and 13 were normal. Of the 55 test cases, 43 had wall thickening and 12 were normal. The LDA classifier was trained with the training set and evaluated with the test set. FROC analysis showed that the system achieved sensitivities of 93.2% and 88.4% for the training and test sets, respectively, at 0.5 FPs/case.

  17. Computer-aided detection of early cancer in the esophagus using HD endoscopy images

    Science.gov (United States)

    van der Sommen, Fons; Zinger, Svitlana; Schoon, Erik J.; de With, Peter H. N.

    2013-02-01

    Esophageal cancer is the fastest rising type of cancer in the Western world. The recent development of High-Definition (HD) endoscopy has enabled the specialist physician to identify cancer at an early stage. Nevertheless, it still requires considerable effort and training to be able to recognize these irregularities associated with early cancer. As a first step towards a Computer-Aided Detection (CAD) system that supports the physician in finding these early stages of cancer, we propose an algorithm that is able to identify irregularities in the esophagus automatically, based on HD endoscopic images. The concept employs tile-based processing, so our system is not only able to identify that an endoscopic image contains early cancer, but it can also locate it. The identification is based on the following steps: (1) preprocessing, (2) feature extraction with dimensionality reduction, (3) classification. We evaluate the detection performance in RGB, HSI and YCbCr color space using the Color Histogram (CH) and Gabor features and we compare with other well-known features to describe texture. For classification, we employ a Support Vector Machine (SVM) and evaluate its performance using different parameters and kernel functions. In experiments, our system achieves a classification accuracy of 95.9% on 50×50 pixel tiles of tumorous and normal tissue and reaches an Area Under the Curve (AUC) of 0.990. In 22 clinical examples our algorithm was able to identify all (pre-)cancerous regions and annotate those regions reasonably well. The experimental and clinical validation are considered promising for a CAD system that supports the physician in finding early stage cancer.

  18. Evaluation of a computer aided X-ray fluorographic system: Part II - image processing

    International Nuclear Information System (INIS)

    Burch, S.F.; Cocking, S.J.

    1981-12-01

    The TV imagery from a computer aided X-ray fluorographic system has been digitally processed with an I 2 S model 70E image processor, controlled by a PDP 11/60 minicomputer. The image processor allowed valuable processing for detection of defects in cast components to be carried out at television frame rates. Summation of TV frames was used to reduce noise, and hence improve the thickness sensitivity of the system. A displaced differencing technique and interactive contrast enhancement were then used to improve the reliability of inspection by removing spurious blemishes and interference lines, while simultaneously enhancing the visibility of real defects. The times required for these operations are given, and the benefits provided for X-ray fluorography are illustrated by the results from inspection of aero engine castings. (author)

  19. Improved cancer detection in automated breast ultrasound by radiologists using Computer Aided Detection

    Energy Technology Data Exchange (ETDEWEB)

    Zelst, J.C.M. van, E-mail: Jan.vanZelst@radboudumc.nl [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands); Tan, T.; Platel, B. [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands); Jong, M. de [Jeroen Bosch Medical Centre, Department of Radiology, ‘s-Hertogenbosch (Netherlands); Steenbakkers, A. [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands); Mourits, M. [Jeroen Bosch Medical Centre, Department of Radiology, ‘s-Hertogenbosch (Netherlands); Grivegnee, A. [Jules Bordet Institute, Department of Radiology, Brussels (Belgium); Borelli, C. [Catholic University of the Sacred Heart, Department of Radiological Sciences, Rome (Italy); Karssemeijer, N.; Mann, R.M. [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands)

    2017-04-15

    Objective: To investigate the effect of dedicated Computer Aided Detection (CAD) software for automated breast ultrasound (ABUS) on the performance of radiologists screening for breast cancer. Methods: 90 ABUS views of 90 patients were randomly selected from a multi-institutional archive of cases collected between 2010 and 2013. This dataset included normal cases (n = 40) with >1 year of follow up, benign (n = 30) lesions that were either biopsied or remained stable, and malignant lesions (n = 20). Six readers evaluated all cases with and without CAD in two sessions. CAD-software included conventional CAD-marks and an intelligent minimum intensity projection of the breast tissue. Readers reported using a likelihood-of-malignancy scale from 0 to 100. Alternative free-response ROC analysis was used to measure the performance. Results: Without CAD, the average area-under-the-curve (AUC) of the readers was 0.77 and significantly improved with CAD to 0.84 (p = 0.001). Sensitivity of all readers improved (range 5.2–10.6%) by using CAD but specificity decreased in four out of six readers (range 1.4–5.7%). No significant difference was observed in the AUC between experienced radiologists and residents both with and without CAD. Conclusions: Dedicated CAD-software for ABUS has the potential to improve the cancer detection rates of radiologists screening for breast cancer.

  20. Improved cancer detection in automated breast ultrasound by radiologists using Computer Aided Detection

    International Nuclear Information System (INIS)

    Zelst, J.C.M. van; Tan, T.; Platel, B.; Jong, M. de; Steenbakkers, A.; Mourits, M.; Grivegnee, A.; Borelli, C.; Karssemeijer, N.; Mann, R.M.

    2017-01-01

    Objective: To investigate the effect of dedicated Computer Aided Detection (CAD) software for automated breast ultrasound (ABUS) on the performance of radiologists screening for breast cancer. Methods: 90 ABUS views of 90 patients were randomly selected from a multi-institutional archive of cases collected between 2010 and 2013. This dataset included normal cases (n = 40) with >1 year of follow up, benign (n = 30) lesions that were either biopsied or remained stable, and malignant lesions (n = 20). Six readers evaluated all cases with and without CAD in two sessions. CAD-software included conventional CAD-marks and an intelligent minimum intensity projection of the breast tissue. Readers reported using a likelihood-of-malignancy scale from 0 to 100. Alternative free-response ROC analysis was used to measure the performance. Results: Without CAD, the average area-under-the-curve (AUC) of the readers was 0.77 and significantly improved with CAD to 0.84 (p = 0.001). Sensitivity of all readers improved (range 5.2–10.6%) by using CAD but specificity decreased in four out of six readers (range 1.4–5.7%). No significant difference was observed in the AUC between experienced radiologists and residents both with and without CAD. Conclusions: Dedicated CAD-software for ABUS has the potential to improve the cancer detection rates of radiologists screening for breast cancer.

  1. Computer-aided detection of breast masses: Four-view strategy for screening mammography

    International Nuclear Information System (INIS)

    Wei Jun; Chan Heangping; Zhou Chuan; Wu Yita; Sahiner, Berkman; Hadjiiski, Lubomir M.; Roubidoux, Marilyn A.; Helvie, Mark A.

    2011-01-01

    Purpose: To improve the performance of a computer-aided detection (CAD) system for mass detection by using four-view information in screening mammography. Methods: The authors developed a four-view CAD system that emulates radiologists' reading by using the craniocaudal and mediolateral oblique views of the ipsilateral breast to reduce false positives (FPs) and the corresponding views of the contralateral breast to detect asymmetry. The CAD system consists of four major components: (1) Initial detection of breast masses on individual views, (2) information fusion of the ipsilateral views of the breast (referred to as two-view analysis), (3) information fusion of the corresponding views of the contralateral breast (referred to as bilateral analysis), and (4) fusion of the four-view information with a decision tree. The authors collected two data sets for training and testing of the CAD system: A mass set containing 389 patients with 389 biopsy-proven masses and a normal set containing 200 normal subjects. All cases had four-view mammograms. The true locations of the masses on the mammograms were identified by an experienced MQSA radiologist. The authors randomly divided the mass set into two independent sets for cross validation training and testing. The overall test performance was assessed by averaging the free response receiver operating characteristic (FROC) curves of the two test subsets. The FP rates during the FROC analysis were estimated by using the normal set only. The jackknife free-response ROC (JAFROC) method was used to estimate the statistical significance of the difference between the test FROC curves obtained with the single-view and the four-view CAD systems. Results: Using the single-view CAD system, the breast-based test sensitivities were 58% and 77% at the FP rates of 0.5 and 1.0 per image, respectively. With the four-view CAD system, the breast-based test sensitivities were improved to 76% and 87% at the corresponding FP rates, respectively

  2. The interplay of attention economics and computer-aided detection marks in screening mammography

    Science.gov (United States)

    Schwartz, Tayler M.; Sridharan, Radhika; Wei, Wei; Lukyanchenko, Olga; Geiser, William; Whitman, Gary J.; Haygood, Tamara Miner

    2016-03-01

    Introduction: According to attention economists, overabundant information leads to decreased attention for individual pieces of information. Computer-aided detection (CAD) alerts radiologists to findings potentially associated with breast cancer but is notorious for creating an abundance of false-positive marks. We suspected that increased CAD marks do not lengthen mammogram interpretation time, as radiologists will selectively disregard these marks when present in larger numbers. We explore the relevance of attention economics in mammography by examining how the number of CAD marks affects interpretation time. Methods: We performed a retrospective review of bilateral digital screening mammograms obtained between January 1, 2011 and February 28, 2014, using only weekend interpretations to decrease distractions and the likelihood of trainee participation. We stratified data according to reader and used ANOVA to assess the relationship between number of CAD marks and interpretation time. Results: Ten radiologists, with median experience after residency of 12.5 years (range 6 to 24,) interpreted 1849 mammograms. When accounting for number of images, Breast Imaging Reporting and Data System category, and breast density, increasing numbers of CAD marks was correlated with longer interpretation time only for the three radiologists with the fewest years of experience (median 7 years.) Conclusion: For the 7 most experienced readers, increasing CAD marks did not lengthen interpretation time. We surmise that as CAD marks increase, the attention given to individual marks decreases. Experienced radiologists may rapidly dismiss larger numbers of CAD marks as false-positive, having learned that devoting extra attention to such marks does not improve clinical detection.

  3. A Multidisciplinary Research Team Approach to Computer-Aided Drafting (CAD) System Selection. Final Report.

    Science.gov (United States)

    Franken, Ken; And Others

    A multidisciplinary research team was assembled to review existing computer-aided drafting (CAD) systems for the purpose of enabling staff in the Design Drafting Department at Linn Technical College (Missouri) to select the best system out of the many CAD systems in existence. During the initial stage of the evaluation project, researchers…

  4. Computer aided detection of clusters of microcalcifications on full field digital mammograms

    International Nuclear Information System (INIS)

    Ge Jun; Sahiner, Berkman; Hadjiiski, Lubomir M.; Chan, H.-P.; Wei Jun; Helvie, Mark A.; Zhou Chuan

    2006-01-01

    We are developing a computer-aided detection (CAD) system to identify microcalcification clusters (MCCs) automatically on full field digital mammograms (FFDMs). The CAD system includes six stages: preprocessing; image enhancement; segmentation of microcalcification candidates; false positive (FP) reduction for individual microcalcifications; regional clustering; and FP reduction for clustered microcalcifications. At the stage of FP reduction for individual microcalcifications, a truncated sum-of-squares error function was used to improve the efficiency and robustness of the training of an artificial neural network in our CAD system for FFDMs. At the stage of FP reduction for clustered microcalcifications, morphological features and features derived from the artificial neural network outputs were extracted from each cluster. Stepwise linear discriminant analysis (LDA) was used to select the features. An LDA classifier was then used to differentiate clustered microcalcifications from FPs. A data set of 96 cases with 192 images was collected at the University of Michigan. This data set contained 96 MCCs, of which 28 clusters were proven by biopsy to be malignant and 68 were proven to be benign. The data set was separated into two independent data sets for training and testing of the CAD system in a cross-validation scheme. When one data set was used to train and validate the convolution neural network (CNN) in our CAD system, the other data set was used to evaluate the detection performance. With the use of a truncated error metric, the training of CNN could be accelerated and the classification performance was improved. The CNN in combination with an LDA classifier could substantially reduce FPs with a small tradeoff in sensitivity. By using the free-response receiver operating characteristic methodology, it was found that our CAD system can achieve a cluster-based sensitivity of 70, 80, and 90 % at 0.21, 0.61, and 1.49 FPs/image, respectively. For case

  5. Computer-aided detection as a decision assistant in chest radiography

    Science.gov (United States)

    Samulski, Maurice R. M.; Snoeren, Peter R.; Platel, Bram; van Ginneken, Bram; Hogeweg, Laurens; Schaefer-Prokop, Cornelia; Karssemeijer, Nico

    2011-03-01

    Background. Contrary to what may be expected, finding abnormalities in complex images like pulmonary nodules in chest radiographs is not dominated by time-consuming search strategies but by an almost immediate global interpretation. This was already known in the nineteen-seventies from experiments with briefly flashed chest radiographs. Later on, experiments with eye-trackers showed that abnormalities attracted the attention quite fast but often without further reader actions. Prolonging one's search seldom leads to newly found abnormalities and may even increase the chance of errors. The problem of reading chest radiographs is therefore not dominated by finding the abnormalities, but by interpreting them. Hypothesis. This suggests that readers could benefit from computer-aided detection (CAD) systems not so much by their ability to prompt potential abnormalities, but more from their ability to 'interpret' the potential abnormalities. In this paper, this hypothesis was investigated by an observer experiment. Experiment. In one condition, the traditional CAD condition, the most suspicious CAD locations were shown to the subjects, without telling them the levels of suspiciousness according to CAD. In the other condition, interactive CAD condition, levels of suspiciousness were given, but only when readers requested them at specified locations. These two conditions focus on decreasing search errors and decision errors, respectively. Results of reading without CAD were also recorded. Six subjects, all non-radiologists, read 223 chest radiographs in both conditions. CAD results were obtained from the OnGuard 5.0 system developed by Riverain Medical (Miamisburg, Ohio). Results. The observer data were analyzed by Location Response Operating Characteristic analysis (LROC). It was found that: 1) With the aid of CAD, the performance is significantly better than without CAD; 2) The performance with interactive CAD is significantly better than with traditional CAD at low false

  6. Energy-aware memory management for embedded multimedia systems a computer-aided design approach

    CERN Document Server

    Balasa, Florin

    2011-01-01

    Energy-Aware Memory Management for Embedded Multimedia Systems: A Computer-Aided Design Approach presents recent computer-aided design (CAD) ideas that address memory management tasks, particularly the optimization of energy consumption in the memory subsystem. It explains how to efficiently implement CAD solutions, including theoretical methods and novel algorithms. The book covers various energy-aware design techniques, including data-dependence analysis techniques, memory size estimation methods, extensions of mapping approaches, and memory banking approaches. It shows how these techniques

  7. Computer aided approach to qualitative and quantitative common cause failure analysis for complex systems

    International Nuclear Information System (INIS)

    Cate, C.L.; Wagner, D.P.; Fussell, J.B.

    1977-01-01

    Common cause failure analysis, also called common mode failure analysis, is an integral part of a complete system reliability analysis. Existing methods of computer aided common cause failure analysis are extended by allowing analysis of the complex systems often encountered in practice. The methods aid in identifying potential common cause failures and also address quantitative common cause failure analysis

  8. Persons with Alzheimer's Disease Make Phone Calls Independently Using a Computer-Aided Telephone System

    Science.gov (United States)

    Perilli, Viviana; Lancioni, Giulio E.; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff; Cassano, Germana; Cordiano, Noemi; Pinto, Katia; Minervini, Mauro G.; Oliva, Doretta

    2012-01-01

    This study assessed whether four patients with a diagnosis of Alzheimer's disease could make independent phone calls via a computer-aided telephone system. The study was carried out according to a non-concurrent multiple baseline design across participants. All participants started with baseline during which the telephone system was not available,…

  9. Computer aided detection of masses in mammography using subregion Hotelling observers

    International Nuclear Information System (INIS)

    Baydush, Alan H.; Catarious, David M.; Abbey, Craig K.; Floyd, Carey E.

    2003-01-01

    We propose to investigate the use of the subregion Hotelling observer for the basis of a computer aided detection scheme for masses in mammography. A database of 1320 regions of interest (ROIs) was selected from the DDSM database collected by the University of South Florida using the Lumisys scanner cases. The breakdown of the cases was as follows: 656 normal ROIs, 307 benign ROIs, and 357 cancer ROIs. Each ROI was extracted at a size of 1024x1024 pixels and subsampled to 128x128 pixels. For the detection task, cancer and benign cases were considered positive and normal was considered negative. All positive cases had the lesion centered in the ROI. We chose to investigate the subregion Hotelling observer as a classifier to detect masses. The Hotelling observer incorporates information about the signal, the background, and the noise correlation for prediction of positive and negative and is the optimal detector when these are known. For our study, 225 subregion Hotelling observers were set up in a 15x15 grid across the center of the ROIs. Each separate observer was designed to 'observe', or discriminate, an 8x8 pixel area of the image. A leave one out training and testing methodology was used to generate 225 'features', where each feature is the output of the individual observers. The 225 features derived from separate Hotelling observers were then narrowed down by using forward searching linear discriminants (LDs). The reduced set of features was then analyzed using an additional LD with receiver operating characteristic (ROC) analysis. The 225 Hotelling observer features were searched by the forward searching LD, which selected a subset of 37 features. This subset of 37 features was then analyzed using an additional LD, which gave a ROC area under the curve of 0.9412+/-0.006 and a partial area of 0.6728. Additionally, at 98% sensitivity the overall classifier had a specificity of 55.9% and a positive predictive value of 69.3%. Preliminary results suggest that

  10. A computer-aided surface roughness measurement system

    International Nuclear Information System (INIS)

    Hughes, F.J.; Schankula, M.H.

    1983-11-01

    A diamond stylus profilometer with computer-based data acquisitions/analysis system is being used to characterize surfaces of reactor components and materials, and to examine the effects of surface topography on thermal contact conductance. The current system is described; measurement problems and system development are discussed in general terms and possible future improvements are outlined

  11. The INGECAD multidisciplinary integrated computer aided engineering system

    International Nuclear Information System (INIS)

    Kisielewicz, L.T.

    1989-01-01

    The purpose of this paper is to define the key criteria of an integrated CAE system, and to discuss the solution developed by Ingevision to match these criteria. An information flow model of process plant engineering is presented as a background to the key criteria of CAE systems. This model includes multidisciplinary interfaces and project changes up to the as-built stage. The key quality criteria of CAE systems correspond to managerial issues, such as project control, to technical issues, consistency and quality assurance, and to economical issues, such as cost optimization. The INGECAD system answers these criteria with a tripod nucleus underlying a set of specialized applications. The nucleus includes a Data Base Management System, basic Graphical Tools, and a Decision Support System. The paper overviews the different modules of the INGECAD system emphasizing the general architecture and the basic tools. Specific examples are developed in functional design, cost optimized items selection, and semi-automated routing of piping system. These examples are not intended to illustrate exhaustively the capabilities of the INGECAD system, but rather to highlight some of the advantages the multidisciplinary integration of the system provides to the users. (orig./HP)

  12. Computer-aided diagnosis workstation and data base system for chest diagnosis based on multihelical CT images

    International Nuclear Information System (INIS)

    Satoh, H.; Niki, N.; Eguchi, K.; Masuda, H.; Machida, S.; Moriyama, N.

    2006-01-01

    We have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images and a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification. We also have developed electronic medical recording system and prototype internet system for the community health in two or more regions by using the Virtual Private Network router, Biometric fingerprint authentication system and Biometric face authentication system for safety of medical information. The results of this study indicate that our computer-aided diagnosis workstation and network system can increase diagnostic speed, diagnostic accuracy and safety of medical information. (author)

  13. Three-dimensional computer aided design system for plant layout

    International Nuclear Information System (INIS)

    Yoshinaga, Toshiaki; Kiguchi, Takashi; Tokumasu, Shinji; Kumamoto, Kenjiro.

    1986-01-01

    The CAD system for three-dimensional plant layout planning, with which the layout of pipings, cable trays, air conditioning ducts and so on in nuclear power plants can be planned and designed effectively in a short period is reported. This system comprises the automatic routing system by storing the rich experience and know-how of designers in a computer as the knowledge, and deciding the layout automatically following the predetermined sequence by using these, the interactive layout system for reviewing the routing results from higher level and modifying to the optimum layout, the layout evaluation system for synthetically evaluating the layout from the viewpoint of the operability such as checkup and maintenance, and the data base system which enables these effective planning and design. In this report, the total constitution of this system and the technical features and effects of the individual subsystems are outlined. In this CAD system for three-dimensional plant layout planning, knowledge engineering, CAD/CAM, computer graphics and other latest technology were introduced, accordingly by applying this system to plant design, the design can be performed quickly, various case studies can be carried out at planning stage, and systematic and optimum layout planning becomes possible. (Kako, I.)

  14. A Computer Aided System for Correlation and Prediction of Phase Equilibrium Data

    DEFF Research Database (Denmark)

    Nielsen, T.L.; Gani, Rafiqul

    2001-01-01

    based on mathematical programming. This paper describes the development of a computer aided system for the systematic derivation of appropriate property models to be used in the service role for a specified problem. As a first step, a library of well-known property models ha's been developed...

  15. Possible Computer Vision Systems and Automated or Computer-Aided Edging and Trimming

    Science.gov (United States)

    Philip A. Araman

    1990-01-01

    This paper discusses research which is underway to help our industry reduce costs, increase product volume and value recovery, and market more accurately graded and described products. The research is part of a team effort to help the hardwood sawmill industry automate with computer vision systems, and computer-aided or computer controlled processing. This paper...

  16. The computer-aided design of a servo system as a multiple-criteria decision problem

    NARCIS (Netherlands)

    Udink ten Cate, A.J.

    1986-01-01

    This paper treats the selection of controller gains of a servo system as a multiple-criteria decision problem. In contrast to the usual optimization-based approaches to computer-aided design, inequality constraints are included in the problem as unconstrained objectives. This considerably simplifies

  17. Performance of computer-aided detection applied to full-field digital mammography in detection of breast cancers

    International Nuclear Information System (INIS)

    Sadaf, Arifa; Crystal, Pavel; Scaranelo, Anabel; Helbich, Thomas

    2011-01-01

    Objective: The aim of this retrospective study was to evaluate performance of computer-aided detection (CAD) with full-field digital mammography (FFDM) in detection of breast cancers. Materials and Methods: CAD was retrospectively applied to standard mammographic views of 127 cases with biopsy proven breast cancers detected with FFDM (Senographe 2000, GE Medical Systems). CAD sensitivity was assessed in total group of 127 cases and for subgroups based on breast density, mammographic lesion type, mammographic lesion size, histopathology and mode of presentation. Results: Overall CAD sensitivity was 91% (115 of 127 cases). There were no statistical differences (p > 0.1) in CAD detection of cancers in dense breasts 90% (53/59) versus non-dense breasts 91% (62/68). There was statistical difference (p 20 mm 97% (22/23). Conclusion: CAD applied to FFDM showed 100% sensitivity in identifying cancers manifesting as microcalcifications only and high sensitivity 86% (71/83) for other mammographic appearances of cancer. Sensitivity is influenced by lesion size. CAD in FFDM is an adjunct helping radiologist in early detection of breast cancers.

  18. Computer-Aided Communication Satellite System Analysis and Optimization.

    Science.gov (United States)

    Stagl, Thomas W.; And Others

    Various published computer programs for fixed/broadcast communication satellite system synthesis and optimization are discussed. The rationale for selecting General Dynamics/Convair's Satellite Telecommunication Analysis and Modeling Program (STAMP) in modified form to aid in the system costing and sensitivity analysis work in the Program on…

  19. Computer aided construction engineering system for nuclear power plants

    International Nuclear Information System (INIS)

    Yoshinaga, Toshiaki; Nakajima, Akira; Miyahara, Ryohei; Miura, Jun

    1990-01-01

    The construction CAE system for nuclear power plants is the tool for the construction work simulator (procedure, processes and management simulation) connected to 3D-CAD (three-dimensional plant layout planning CAD). The data used for construction work simulation are registered in the data base as the installation smallest unit data from the 3D-CAD. This construction work simulator comprises the automatic installation procedure decision system, with which a construction planner decides installation procedure by using a high performance graphic work station, and based on a 3D-CAD model, utilizing empirical procedure logic, the dialogue system for making the installation procedure more optimal by utilizing effectively the graphic function, the evaluation system for synthetically evaluating workability, personnel plan and so on by adding the simulation of human behavior based on these procedures, the schedule system which carries out work process simulation based on the above, the data base system for letting to do these plans effectively and the project management system. By means of these, the plant construction of high quality is expected. (K.I.)

  20. Computer aided fault tree construction for electrical systems

    International Nuclear Information System (INIS)

    Fussell, J.B.

    1975-01-01

    A technique is presented for automated construction of the Boolean failure logic diagram, called the fault tree, for electrical systems. The method is a technique for synthesizing a fault tree from system-independent component characteristics. Terminology is defined and heuristic examples are given for all phases of the model. The computer constructed fault trees are in conventional format, use conventional symbols, and are deductively constructed from the main failure of interest to the individual component failures. The synthesis technique is generally applicable to automated fault tree construction for other types of systems

  1. Introduction to ISOCAD (Integrated System of Computer Aided Dosimetry)

    International Nuclear Information System (INIS)

    Shrivastava, Amit

    2014-01-01

    A novel, bar code based computerized application package from BRIT for the Ceric cerous Potentiometric Dose Measurement System for Gamma Irradiators. The present generation of gamma irradiators operating worldwide and catering to the radiation processing requirements of medium and high dose products from the healthcare and food processing industry invariably resort to Ceric cerous Potentiometric Dose Measurement Systems (CCPDMs). BRIT, being of the major supplier of this dose measurement system in the country has expanded its clientele to the Asian continent as well in the recent past, had been endeavoring to provide its valued clients this internationally acclaimed dose measurement system at competitive pricing. The perpetually changing quality conscious business environment with demanding cGMP requirements particularly from the healthcare and the food sector propelled the development of the ISOCAD

  2. Computer-aided visualization and analysis system for sequence evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Chee, Mark S.; Wang, Chunwei; Jevons, Luis C.; Bernhart, Derek H.; Lipshutz, Robert J.

    2004-05-11

    A computer system for analyzing nucleic acid sequences is provided. The computer system is used to perform multiple methods for determining unknown bases by analyzing the fluorescence intensities of hybridized nucleic acid probes. The results of individual experiments are improved by processing nucleic acid sequences together. Comparative analysis of multiple experiments is also provided by displaying reference sequences in one area and sample sequences in another area on a display device.

  3. Computer-aided segmentation system for 3D chest CT

    International Nuclear Information System (INIS)

    Iwasawa, Tae; Komagata, Takanobu; Ogura, Takashi; Iwao, Yuma; Goto, Toshiyuki; Asakura, Akira; Inoue, Tomio

    2012-01-01

    We will introduce the quantitative analysis of the chest CT images using computer-assisted segmentation system (Gaussian Histogram Normalized Correlation; GHNC). This system can divide the lung into several patterns, for example, normal, emphysema and fibrous lesion, and measure each lesion volume quantitatively. We analyzed 3D-CT images of 20 patients with lung cancer. GHNC could measure the volumes of emphysema and fibrosis lesions, respectively. GHNC analysis will be feasible for preoperative CT evaluation, especially in the patients with combined pulmonary fibrosis and emphysema. (author)

  4. ROCK-CAD - computer aided geological modelling system

    International Nuclear Information System (INIS)

    Saksa, P.

    1995-12-01

    The study discusses surface and solid modelling methods, their use and interfacing with geodata. Application software named ROCK-CAD suitable for geological bedrock modelling has been developed with support from Teollisuuden Voima Oy (TVO). It has been utilized in the Finnish site characterization programme for spent nuclear fuel waste disposal during the 1980s and 1990s. The system is based on the solid modelling technique. It comprises also rich functionality for the particular geological modelling scheme. The ROCK-CAD system provides, among other things, varying graphical vertical and horizontal intersections and perspective illustrations. The specially developed features are the application of the boundary representation modelling method, parametric object generation language and the discipline approach. The ROCK-CAD system has been utilized in modelling spatial distribution of rock types and fracturing structures in TVO's site characterization. The Olkiluoto site at Eurajoki serves as an example case. The study comprises the description of the modelling process, models and illustration examples. The utilization of bedrock models in site characterization, in tentative repository siting as well as in groundwater flow simulation is depicted. The application software has improved the assessment of the sites studied, given a new basis for the documentation of interpretation and modelling work, substituted hand-drawing and enabled digital transfer to numerical analysis. Finally, aspects of presentation graphics in geological modelling are considered. (84 refs., 30 figs., 11 tabs.)

  5. Computer-aided system for interactive psychomotor testing

    Science.gov (United States)

    Selivanova, Karina G.; Ignashchuk, Olena V.; Koval, Leonid G.; Kilivnik, Volodymyr S.; Zlepko, Alexandra S.; Sawicki, Daniel; Kalizhanova, Aliya; Zhanpeisova, Aizhan; Smailova, Saule

    2017-08-01

    Nowadays research of psychomotor actions has taken a special place in education, sports, medicine, psychology etc. Development of computer system for psychomotor testing could help solve many operational problems in psychoneurology and psychophysiology and also determine the individual characteristics of fine motor skills. This is particularly relevant issue when it comes to children, students, athletes for definition of personal and professional features. The article presents the dynamics of a developing psychomotor skills and application in the training process of means. The results of testing indicated their significant impact on psychomotor skills development.

  6. Machine Learning in Ultrasound Computer-Aided Diagnostic Systems: A Survey.

    Science.gov (United States)

    Huang, Qinghua; Zhang, Fan; Li, Xuelong

    2018-01-01

    The ultrasound imaging is one of the most common schemes to detect diseases in the clinical practice. There are many advantages of ultrasound imaging such as safety, convenience, and low cost. However, reading ultrasound imaging is not easy. To support the diagnosis of clinicians and reduce the load of doctors, many ultrasound computer-aided diagnosis (CAD) systems are proposed. In recent years, the success of deep learning in the image classification and segmentation led to more and more scholars realizing the potential of performance improvement brought by utilizing the deep learning in the ultrasound CAD system. This paper summarized the research which focuses on the ultrasound CAD system utilizing machine learning technology in recent years. This study divided the ultrasound CAD system into two categories. One is the traditional ultrasound CAD system which employed the manmade feature and the other is the deep learning ultrasound CAD system. The major feature and the classifier employed by the traditional ultrasound CAD system are introduced. As for the deep learning ultrasound CAD, newest applications are summarized. This paper will be useful for researchers who focus on the ultrasound CAD system.

  7. Machine Learning in Ultrasound Computer-Aided Diagnostic Systems: A Survey

    Directory of Open Access Journals (Sweden)

    Qinghua Huang

    2018-01-01

    Full Text Available The ultrasound imaging is one of the most common schemes to detect diseases in the clinical practice. There are many advantages of ultrasound imaging such as safety, convenience, and low cost. However, reading ultrasound imaging is not easy. To support the diagnosis of clinicians and reduce the load of doctors, many ultrasound computer-aided diagnosis (CAD systems are proposed. In recent years, the success of deep learning in the image classification and segmentation led to more and more scholars realizing the potential of performance improvement brought by utilizing the deep learning in the ultrasound CAD system. This paper summarized the research which focuses on the ultrasound CAD system utilizing machine learning technology in recent years. This study divided the ultrasound CAD system into two categories. One is the traditional ultrasound CAD system which employed the manmade feature and the other is the deep learning ultrasound CAD system. The major feature and the classifier employed by the traditional ultrasound CAD system are introduced. As for the deep learning ultrasound CAD, newest applications are summarized. This paper will be useful for researchers who focus on the ultrasound CAD system.

  8. Studies on computer-aided diagnosis systems for chest radiographs and mammograms (in Japanese)

    International Nuclear Information System (INIS)

    Hara, Takeshi

    2001-01-01

    This thesis describes computer-aided diagnosis (CAD) systems for chest radiographs and mammograms. Preprocessing and imaging processing methods for each CAD system include dynamic range compression and region segmentation technique. A new pattern recognition technique combines genetic algorithms with template matching methods to detect lung nodules. A genetic algorithm was employed to select the optimal shape of simulated nodular shadows to be compared with real lesions on digitized chest images. Detection performance was evaluated using 332 chest radiographs from the database of the Japanese Society of Radiological Technology. Our average true-positive rate was 72.8% with an average of 11 false-positive findings per image. A new detection method using high resolution digital images with 0.05 mm sampling is also proposed for the mammogram CAD system to detect very small microcalcifications. An automated classification method uses feature extraction based on fractal dimension analysis of masses. Using over 200 cases to evaluate the detection of mammographic masses and calcifications, the detection rate of masses and microcalcifications were 87% and 96% with 1.5 and 1.8 false-positive findings, respectively. The classification performance on benign vs malignant lesions, the Az values that were defined by the areas under the ROC curves derived from classification schemes of masses and microcalcifications were 0.84 and 0.89. To demonstrate the practicality of these CAD systems in a computer-network environment, we propose to use the mammogram CAD system via the Internet and WWW. A common gateway interface and server-client approach for the CAD system via the Internet will permit display of the CAD results on ordinary computers

  9. Computer aided radiation protection system at Tokai reprocessing plant

    International Nuclear Information System (INIS)

    Ishida, J.; Saruta, J.; Yonezawa, R.

    1996-01-01

    Radiation control for workers and workforce has been carried out strictly and effectively taking into account ALARA principle at Tokai Reprocessing Plant (TRP) which has treated about 860 tons of irradiated fuels by now since 1977. The outline of radiation control method at TRP has already been described. This paper briefly describes our experiences and the capabilities of Radiological Information Management System (RIMS) for the safety operation of TRP, followed by radiation exposure control and activity discharge control as examples. By operating the RIMS, the conditions of workplace such as dose equivalent rate and air-contamination are easily and rapidly grasped to take prompt countermeasures for radiological protection, localization and elimination of contamination, and also the past experience data are properly applied to new radiological works to reduce exposures associated with routine and special repetitive maintenance operations at TRP. Finally, authors would like to emphasize that the form and system for radiological control of reprocessing plant has been established throughout our 15-year-experience at TRP. (author)

  10. Observer training for computer-aided detection of pulmonary nodules in chest radiography.

    Science.gov (United States)

    De Boo, Diederick W; van Hoorn, François; van Schuppen, Joost; Schijf, Laura; Scheerder, Maeke J; Freling, Nicole J; Mets, Onno; Weber, Michael; Schaefer-Prokop, Cornelia M

    2012-08-01

    To assess whether short-term feedback helps readers to increase their performance using computer-aided detection (CAD) for nodule detection in chest radiography. The 140 CXRs (56 with a solitary CT-proven nodules and 84 negative controls) were divided into four subsets of 35; each were read in a different order by six readers. Lesion presence, location and diagnostic confidence were scored without and with CAD (IQQA-Chest, EDDA Technology) as second reader. Readers received individual feedback after each subset. Sensitivity, specificity and area under the receiver-operating characteristics curve (AUC) were calculated for readings with and without CAD with respect to change over time and impact of CAD. CAD stand-alone sensitivity was 59 % with 1.9 false-positives per image. Mean AUC slightly increased over time with and without CAD (0.78 vs. 0.84 with and 0.76 vs. 0.82 without CAD) but differences did not reach significance. The sensitivity increased (65 % vs. 70 % and 66 % vs. 70 %) and specificity decreased over time (79 % vs. 74 % and 80 % vs. 77 %) but no significant impact of CAD was found. Short-term feedback does not increase the ability of readers to differentiate true- from false-positive candidate lesions and to use CAD more effectively. • Computer-aided detection (CAD) is increasingly used as an adjunct for many radiological techniques. • Short-term feedback does not improve reader performance with CAD in chest radiography. • Differentiation between true- and false-positive CAD for low conspicious possible lesions proves difficult. • CAD can potentially increase reader performance for nodule detection in chest radiography.

  11. Development of computer aided engineering system for TRAC applications

    International Nuclear Information System (INIS)

    Arai, Kenji; Itoya, Seihiro; Uematsu, Hitoshi; Tsunoyama, Shigeaki

    1990-01-01

    An advanced best estimate computer program for nuclear reactor transient analysis, TRAC has been extensively used to carry out various thermal hydraulic calculations in the nuclear engineering field, because of its versatility. To perform efficiently a wide variety of TRAC calculation, the efficient utilization of computers and the convenient environment for input and output processing is necessary. We have applied a computer network comprising a super-computer, engineering work stations and personal computers to TRAC calculations and have assigned the appropriate functions to each computer. We have also been developing an interactive graphics system for input and output processing on an EWS. This hardware and software environment can improve the effectiveness of TRAC utilization for various thermal hydraulic calculations. (author)

  12. Evolution of facility layout requirements and CAD [computer-aided design] system development

    International Nuclear Information System (INIS)

    Jones, M.

    1990-06-01

    The overall configuration of the Superconducting Super Collider (SSC) including the infrastructure and land boundary requirements were developed using a computer-aided design (CAD) system. The evolution of the facility layout requirements and the use of the CAD system are discussed. The emphasis has been on minimizing the amount of input required and maximizing the speed by which the output may be obtained. The computer system used to store the data is also described

  13. Computer-aided-engineering system for modeling and analysis of ECLSS integration testing

    Science.gov (United States)

    Sepahban, Sonbol

    1987-01-01

    The accurate modeling and analysis of two-phase fluid networks found in environmental control and life support systems is presently undertaken by computer-aided engineering (CAE) techniques whose generalized fluid dynamics package can solve arbitrary flow networks. The CAE system for integrated test bed modeling and analysis will also furnish interfaces and subsystem/test-article mathematical models. Three-dimensional diagrams of the test bed are generated by the system after performing the requisite simulation and analysis.

  14. Modelling physics detectors in a computer aided design system for simulation purposes

    International Nuclear Information System (INIS)

    Ahvenainen, J.; Oksakivi, T.; Vuoskoski, J.

    1995-01-01

    The possibility of transferring physics detector models from computer aided design systems into physics simulation packages like GEANT is receiving increasing attention. The problem of exporting detector models constructed in CAD systems into GEANT is well known. We discuss the problem and describe an application, called DDT, which allows one to design detector models in a CAD system and then transfer the models into GEANT for simulation purposes. (orig.)

  15. Computer-aided Nonlinear Control System Design Using Describing Function Models

    CERN Document Server

    Nassirharand, Amir

    2012-01-01

    A systematic computer-aided approach provides a versatile setting for the control engineer to overcome the complications of controller design for highly nonlinear systems. Computer-aided Nonlinear Control System Design provides such an approach based on the use of describing functions. The text deals with a large class of nonlinear systems without restrictions on the system order, the number of inputs and/or outputs or the number, type or arrangement of nonlinear terms. The strongly software-oriented methods detailed facilitate fulfillment of tight performance requirements and help the designer to think in purely nonlinear terms, avoiding the expedient of linearization which can impose substantial and unrealistic model limitations and drive up the cost of the final product. Design procedures are presented in a step-by-step algorithmic format each step being a functional unit with outputs that drive the other steps. This procedure may be easily implemented on a digital computer with example problems from mecha...

  16. Analysis of three-phase power-supply systems using computer-aided design programs

    International Nuclear Information System (INIS)

    Oberst, E.F.

    1977-01-01

    A major concern of every designer of large, three-phase power-supply systems is the protection of system components from overvoltage transients. At present, three computer-aided circuit design programs are available in the Magnetic Fusion Energy (MFE) National Computer Center that can be used to analyze three-phase power systems: MINI SCEPTRE, SPICE I, and SPICE II. These programs have been used at Lawrence Livermore Laboratory (LLL) to analyze the operation of a 200-kV dc, 20-A acceleration power supply for the High Voltage Test Stand. Various overvoltage conditions are simulated and the effectiveness of system protective devices is observed. The simulated overvoltage conditions include such things as circuit breaker openings, pulsed loading, and commutation voltage surges in the rectifiers. These examples are used to illustrate the use of the computer-aided, circuit-design programs discussed in this paper

  17. Image-processing techniques used in the computer-aided detection of radiographic lesions in anatomic background

    International Nuclear Information System (INIS)

    Giger, M.L.; Doi, K.; MacMahon, H.; Yin, F.F.

    1988-01-01

    The authors developed feature-extraction techniques for use in the computer-aided detection of pulmonary nodules in digital chest images. Use of such a computer-aided detection scheme, which would alert radiologists to the locations of suspected lung nodules, is expected to reduce the number of false-negative diagnoses. False-negative diagnoses (i.e., misses) are a current problem in chest radiology with ''miss-rates'' as high as 30%. This may be due to the camouflaging effect of surrounding anatomic background on the nodule, or to the subjective and varying decision criteria used by radiologists

  18. Effect of computer-aided detection as a second reader in multidetector-row CT colonography

    International Nuclear Information System (INIS)

    Mang, Thomas; Peloschek, Philipp; Plank, Christina; Maier, Andrea; Weber, Michael; Herold, Christian; Schima, Wolfgang; Graser, Anno; Bogoni, Luca

    2007-01-01

    Our purpose was to assess the effect of computer-aided detection (CAD) on lesion detection as a second reader in computed tomographic colonography, and to compare the influence of CAD on the performance of readers with different levels of expertise. Fifty-two CT colonography patient data-sets (37 patients: 55 endoscopically confirmed polyps ≥0.5 cm, seven cancers; 15 patients: no abnormalities) were retrospectively reviewed by four radiologists (two expert, two nonexpert). After primary data evaluation, a second reading augmented with findings of CAD (polyp-enhanced view, Siemens) was performed. Sensitivities and reading time were calculated for each reader without CAD and supported by CAD findings. The sensitivity of expert readers was 91% each, and of nonexpert readers, 76% and 75%, respectively, for polyp detection. CAD increased the sensitivity of expert readers to 96% (P = 0.25) and 93% (P = 1), and that of nonexpert readers to 91% (P = 0.008) and 95% (P = 0.001), respectively. All four readers diagnosed 100% of cancers, but CAD alone only 43%. CAD increased reading time by 2.1 min (mean). CAD as a second reader significantly improves sensitivity for polyp detection in a high disease prevalence population for nonexpert readers. CAD causes a modest increase in reading time. CAD is of limited value in the detection of cancer. (orig.)

  19. Computer Aided Design and Analysis of Separation Processes with Electrolyte Systems

    DEFF Research Database (Denmark)

    A methodology for computer aided design and analysis of separation processes involving electrolyte systems is presented. The methodology consists of three main parts. The thermodynamic part "creates" the problem specific property model package, which is a collection of pure component and mixture...... property models. The design and analysis part generates process (flowsheet) alternatives, evaluates/analyses feasibility of separation and provides a visual operation path for the desired separation. The simulation part consists of a simulation/calculation engine that allows the screening and validation...... of process alternatives. For the simulation part, a general multi-purpose, multi-phase separation model has been developed and integrated to an existing computer aided system. Application of the design and analysis methodology is highlighted through two illustrative case studies....

  20. Computer Aided Design and Analysis of Separation Processes with Electrolyte Systems

    DEFF Research Database (Denmark)

    Takano, Kiyoteru; Gani, Rafiqul; Kolar, P.

    2000-01-01

    A methodology for computer aided design and analysis of separation processes involving electrolyte systems is presented. The methodology consists of three main parts. The thermodynamic part 'creates' the problem specific property model package, which is a collection of pure component and mixture...... property models. The design and analysis part generates process (flowsheet) alternatives, evaluates/analyses feasibility of separation and provides a visual operation path for the desired separation. The simulation part consists of a simulation/calculation engine that allows the screening and validation...... of process alternatives. For the simulation part, a general multi-purpose, multi-phase separation model has been developed and integrated to an existing computer aided system. Application of the design and analysis methodology is highlighted through two illustrative case studies, (C) 2000 Elsevier Science...

  1. CT colonography: computer-aided detection of morphologically flat T1 colonic carcinoma

    International Nuclear Information System (INIS)

    Taylor, Stuart A.; Iinuma, Gen; Saito, Yutaka; Zhang, Jie; Halligan, Steve

    2008-01-01

    The purpose was to evaluate the ability of computer-aided detection (CAD) software to detect morphologically flat early colonic carcinoma using CT colonography (CTC). Twenty-four stage T1 colonic carcinomas endoscopically classified as flat (width over twice height) were accrued from patients undergoing staging CTC. Tumor location was annotated by three experienced radiologists in consensus aided by the endosocpic report. CAD software was then applied at three settings of sphericity (0, 0.75, and 1). Computer prompts were categorized as either true positive (overlapping tumour boundary) or false positive. True positives were subclassified as focal or non focal. The 24 cancers were endoscopically classified as type IIa (n=11) and type IIa+IIc (n=13). Mean size (range) was 27 mm (7-70 mm). CAD detected 20 (83.3%), 17 (70.8%), and 13 (54.1%) of the 24 cancers at filter settings of 0, 0.75, and 1, respectively with 3, 4, and 8 missed cancers of type IIa, respectively. The mean total number of false-positive CAD marks per patient at each filter setting was 36.5, 21.1, and 9.5, respectively, excluding polyps. At all settings, >96.1% of CAD true positives were classified as focal. CAD may be effective for the detection of morphologically flat cancer, although minimally raised laterally spreading tumors remain problematic. (orig.)

  2. Computer-aided detection of early interstitial lung diseases using low-dose CT images

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang Cheol; Kim, Soo Hyung [School of Electronics and Computer Engineering, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Tan, Jun; Wang Xingwei; Lederman, Dror; Leader, Joseph K; Zheng Bin, E-mail: zhengb@upmc.edu [Department of Radiology, University of Pittsburgh, Pittsburgh, PA 15213 (United States)

    2011-02-21

    This study aims to develop a new computer-aided detection (CAD) scheme to detect early interstitial lung disease (ILD) using low-dose computed tomography (CT) examinations. The CAD scheme classifies each pixel depicted on the segmented lung areas into positive or negative groups for ILD using a mesh-grid-based region growth method and a multi-feature-based artificial neural network (ANN). A genetic algorithm was applied to select optimal image features and the ANN structure. In testing each CT examination, only pixels selected by the mesh-grid region growth method were analyzed and classified by the ANN to improve computational efficiency. All unselected pixels were classified as negative for ILD. After classifying all pixels into the positive and negative groups, CAD computed a detection score based on the ratio of the number of positive pixels to all pixels in the segmented lung areas, which indicates the likelihood of the test case being positive for ILD. When applying to an independent testing dataset of 15 positive and 15 negative cases, the CAD scheme yielded the area under receiver operating characteristic curve (AUC = 0.884 {+-} 0.064) and 80.0% sensitivity at 85.7% specificity. The results demonstrated the feasibility of applying the CAD scheme to automatically detect early ILD using low-dose CT examinations.

  3. Computer-aided System of Semantic Text Analysis of a Technical Specification

    OpenAIRE

    Zaboleeva-Zotova, Alla; Orlova, Yulia

    2008-01-01

    The given work is devoted to development of the computer-aided system of semantic text analysis of a technical specification. The purpose of this work is to increase efficiency of software engineering based on automation of semantic text analysis of a technical specification. In work it is offered and investigated the model of the analysis of the text of the technical project is submitted, the attribute grammar of a technical specification, intended for formalization of limited Ru...

  4. An integrated computer aided system for integrated design of chemical processes

    DEFF Research Database (Denmark)

    Gani, Rafiqul; Hytoft, Glen; Jaksland, Cecilia

    1997-01-01

    In this paper, an Integrated Computer Aided System (ICAS), which is particularly suitable for solving problems related to integrated design of chemical processes; is presented. ICAS features include a model generator (generation of problem specific models including model simplification and model ...... form the basis for the toolboxes. The available features of ICAS are highlighted through a case study involving the separation of binary azeotropic mixtures. (C) 1997 Elsevier Science Ltd....

  5. Decomposition recovery extension to the Computer Aided Prototyping System (CAPS) change-merge tool.

    OpenAIRE

    Keesling, William Ronald

    1997-01-01

    Approved for public release; distribution is unlimited A promising use of Computer Aided Prototyping System (CAPS) is to support concurrent design. Key to success in this context is the ability to automatically and reliably combine and integrate the prototypes produced in concurrent efforts. Thus, to be of practical use in this as well as most prototyping contexts, a CAPS tool must have a fast, automated, reliable prototype integration capability. The current CAPS Change Merge Tool is fast...

  6. Unit cell-based computer-aided manufacturing system for tissue engineering

    International Nuclear Information System (INIS)

    Kang, Hyun-Wook; Park, Jeong Hun; Kang, Tae-Yun; Seol, Young-Joon; Cho, Dong-Woo

    2012-01-01

    Scaffolds play an important role in the regeneration of artificial tissues or organs. A scaffold is a porous structure with a micro-scale inner architecture in the range of several to several hundreds of micrometers. Therefore, computer-aided construction of scaffolds should provide sophisticated functionality for porous structure design and a tool path generation strategy that can achieve micro-scale architecture. In this study, a new unit cell-based computer-aided manufacturing (CAM) system was developed for the automated design and fabrication of a porous structure with micro-scale inner architecture that can be applied to composite tissue regeneration. The CAM system was developed by first defining a data structure for the computing process of a unit cell representing a single pore structure. Next, an algorithm and software were developed and applied to construct porous structures with a single or multiple pore design using solid freeform fabrication technology and a 3D tooth/spine computer-aided design model. We showed that this system is quite feasible for the design and fabrication of a scaffold for tissue engineering. (paper)

  7. Unit cell-based computer-aided manufacturing system for tissue engineering.

    Science.gov (United States)

    Kang, Hyun-Wook; Park, Jeong Hun; Kang, Tae-Yun; Seol, Young-Joon; Cho, Dong-Woo

    2012-03-01

    Scaffolds play an important role in the regeneration of artificial tissues or organs. A scaffold is a porous structure with a micro-scale inner architecture in the range of several to several hundreds of micrometers. Therefore, computer-aided construction of scaffolds should provide sophisticated functionality for porous structure design and a tool path generation strategy that can achieve micro-scale architecture. In this study, a new unit cell-based computer-aided manufacturing (CAM) system was developed for the automated design and fabrication of a porous structure with micro-scale inner architecture that can be applied to composite tissue regeneration. The CAM system was developed by first defining a data structure for the computing process of a unit cell representing a single pore structure. Next, an algorithm and software were developed and applied to construct porous structures with a single or multiple pore design using solid freeform fabrication technology and a 3D tooth/spine computer-aided design model. We showed that this system is quite feasible for the design and fabrication of a scaffold for tissue engineering.

  8. Computer- Aided diagnosis system for the evaluation of chronic obstructive pulmonary disease on CT Images

    Directory of Open Access Journals (Sweden)

    Parsa Hosseini M

    2011-03-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Chronic Obstructive Pulmonary Disease (COPD is one of the most prevalent pulmonary diseases. Use of an automatic system for the detection and diagnosis of the disease will be beneficial to the patients' treatment decision-making process. In this paper, we propose a new approach for the Computer Aided Diagnosis (CAD of the disease and determination of its severity axial CT scan images."n"nMethods: In this study, 24 lung CT scans in full inspiratory and expiratory states were performed. Variations in the normalized pattern of the lungs' external parenchyma were exploited as a feature for COPD diagnosis. Subsequently, a Bayesian classifier was used to classify variations into two normal and abnormal patterns for the discrimination of patients and healthy individuals. Finally, the accuracy of the classification was assessed statistically. "n"nResults: With the proposed method, the lungs parenchymal elasticity and air-trapping were determined quantitatively. The more this feature tended to zero, the more severe air-trapping and obstructive pulmonary disease is. By analyzing CT images in the healthy and patient groups, we calculated the hard threshold for the diagnosis of the disease. Clinical results

  9. Three-Dimensional Computer-Aided Detection of Microcalcification Clusters in Digital Breast Tomosynthesis

    Directory of Open Access Journals (Sweden)

    Ji-wook Jeong

    2016-01-01

    Full Text Available We propose computer-aided detection (CADe algorithm for microcalcification (MC clusters in reconstructed digital breast tomosynthesis (DBT images. The algorithm consists of prescreening, MC detection, clustering, and false-positive (FP reduction steps. The DBT images containing the MC-like objects were enhanced by a multiscale Hessian-based three-dimensional (3D objectness response function and a connected-component segmentation method was applied to extract the cluster seed objects as potential clustering centers of MCs. Secondly, a signal-to-noise ratio (SNR enhanced image was also generated to detect the individual MC candidates and prescreen the MC-like objects. Each cluster seed candidate was prescreened by counting neighboring individual MC candidates nearby the cluster seed object according to several microcalcification clustering criteria. As a second step, we introduced bounding boxes for the accepted seed candidate, clustered all the overlapping cubes, and examined. After the FP reduction step, the average number of FPs per case was estimated to be 2.47 per DBT volume with a sensitivity of 83.3%.

  10. Detection Efficiency of Microcalcification using Computer Aided Diagnosis in the Breast Ultrasonography Images

    International Nuclear Information System (INIS)

    Lee, Jin Soo; Ko, Seong Jin; Kang, Se Sik; Kim, Jung Hoon; Choi, Seok Yoon; Kim, Chang Soo; Park, Hyung Hu

    2012-01-01

    Digital Mammography makes it possible to reproduce the entire breast image. And it is used to detect microcalcification and mass which are the most important point of view of nonpalpable early breast cancer, so it has been used as the primary screening test of breast disease. It is reported that microcalcification of breast lesion is important in diagnosis of early breast cancer. In this study, six types of texture features algorithms are used to detect microcalcification on breast US images and the study has analyzed recognition rate of lesion between normal US images and other US images which microcalification is seen. As a result of the experiment, Computer aided diagnosis recognition rate that distinguishes mammography and breast US disease was considerably high 70-98%. The average contrast and entropy parameters were low in ROC analysis, but sensitivity and specificity of four types parameters were over 90%. Therefore it is possible to detect microcalcification on US images. If not only six types of texture features algorithms but also the research of additional parameter algorithm is being continually proceeded and basis of practical use on CAD is being prepared, it can be a important meaning as pre-reading. Also, it is considered very useful things for early diagnosis of breast cancer.

  11. Computer-aided diagnosis workstation and telemedicine network system for chest diagnosis based on multislice CT images

    Science.gov (United States)

    Satoh, Hitoshi; Niki, Noboru; Eguchi, Kenji; Ohmatsu, Hironobu; Kakinuma, Ryutaru; Moriyama, Noriyuki

    2009-02-01

    Mass screening based on multi-helical CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. Moreover, the doctor who diagnoses a medical image is insufficient in Japan. To overcome these problems, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images, a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification and a vertebra body analysis algorithm for quantitative evaluation of osteoporosis likelihood by using helical CT scanner for the lung cancer mass screening. The functions to observe suspicious shadow in detail are provided in computer-aided diagnosis workstation with these screening algorithms. We also have developed the telemedicine network by using Web medical image conference system with the security improvement of images transmission, Biometric fingerprint authentication system and Biometric face authentication system. Biometric face authentication used on site of telemedicine makes "Encryption of file" and "Success in login" effective. As a result, patients' private information is protected. We can share the screen of Web medical image conference system from two or more web conference terminals at the same time. An opinion can be exchanged mutually by using a camera and a microphone that are connected with workstation. Based on these diagnostic assistance methods, we have developed a new computer-aided workstation and a new telemedicine network that can display suspected lesions three-dimensionally in a short time. The results of this study indicate that our radiological information system without film by using computer-aided diagnosis workstation and our telemedicine network system can increase diagnostic speed, diagnostic accuracy and

  12. A dimension reduction strategy for improving the efficiency of computer-aided detection for CT colonography

    Science.gov (United States)

    Song, Bowen; Zhang, Guopeng; Wang, Huafeng; Zhu, Wei; Liang, Zhengrong

    2013-02-01

    Various types of features, e.g., geometric features, texture features, projection features etc., have been introduced for polyp detection and differentiation tasks via computer aided detection and diagnosis (CAD) for computed tomography colonography (CTC). Although these features together cover more information of the data, some of them are statistically highly-related to others, which made the feature set redundant and burdened the computation task of CAD. In this paper, we proposed a new dimension reduction method which combines hierarchical clustering and principal component analysis (PCA) for false positives (FPs) reduction task. First, we group all the features based on their similarity using hierarchical clustering, and then PCA is employed within each group. Different numbers of principal components are selected from each group to form the final feature set. Support vector machine is used to perform the classification. The results show that when three principal components were chosen from each group we can achieve an area under the curve of receiver operating characteristics of 0.905, which is as high as the original dataset. Meanwhile, the computation time is reduced by 70% and the feature set size is reduce by 77%. It can be concluded that the proposed method captures the most important information of the feature set and the classification accuracy is not affected after the dimension reduction. The result is promising and further investigation, such as automatically threshold setting, are worthwhile and are under progress.

  13. Computer-aided detection of breast carcinoma in standard mammographic projections with digital mammography

    Energy Technology Data Exchange (ETDEWEB)

    Destounis, Stamatia [Elizabeth Wende Breast Care, LLC, Rochester, NY (United States); University of Rochester, School of Medicine and Dentistry, Rochester, NY (United States); Hanson, Sarah; Morgan, Renee; Murphy, Philip; Somerville, Patricia; Seifert, Posy; Andolina, Valerie; Arieno, Andrea; Skolny, Melissa; Logan-Young, Wende [Elizabeth Wende Breast Care, LLC, Rochester, NY (United States)

    2009-06-15

    A retrospective evaluation of the ability of computer-aided detection (CAD) ability to identify breast carcinoma in standard mammographic projections. Forty-five biopsy proven lesions in 44 patients imaged digitally with CAD applied at examination were reviewed. Forty-four screening BIRADS {sup registered} category 1 digital mammography examinations were randomly identified to serve as a comparative normal/control population. Data included patient age; BIRADS {sup registered} breast density; lesion type, size, and visibility; number, type, and location of CAD marks per image; CAD ability to mark lesions; needle core and surgical pathologic correlation. The CAD lesion/case sensitivity of 87% (n=39), image sensitivity of 69% (n=31) for mediolateral oblique view and 78% (n=35) for the craniocaudal view was found. The average false positive rate in 44 normal screening cases was 2.0 (range 1-8). The 2.0 figure is based on 88 reported false positive CAD marks in 44 normal screening exams: 98% (n=44) lesions proceeded to excision; initial pathology upgraded at surgical excision from in situ to invasive disease in 24% (n=9) lesions. CAD demonstrated potential to detect mammographically visible cancers in standard projections for all lesion types. (orig.)

  14. Effect of radiation dose reduction and iterative reconstruction on computer-aided detection of pulmonary nodules : Intra-individual comparison

    NARCIS (Netherlands)

    Den Harder, Annemarie M.; Willemink, Martin J.; Van Hamersvelt, Robbert W.; Vonken, Evert-Jan P A; Milles, Julien; Schilham, Arnold M R; Lammers, Jan Willem; De Jong, Pim A.; Leiner, Tim; Budde, Ricardo P J

    2016-01-01

    Objective To evaluate the effect of radiation dose reduction and iterative reconstruction (IR) on the performance of computer-aided detection (CAD) for pulmonary nodules. Methods In this prospective study twenty-five patients were included who were scanned for pulmonary nodule follow-up. Image

  15. Computer-aided Detection Fidelity of Pulmonary Nodules in Chest Radiograph

    Directory of Open Access Journals (Sweden)

    Nikolaos Dellios

    2017-01-01

    Full Text Available Aim: The most ubiquitous chest diagnostic method is the chest radiograph. A common radiographic finding, quite often incidental, is the nodular pulmonary lesion. The detection of small lesions out of complex parenchymal structure is a daily clinical challenge. In this study, we investigate the efficacy of the computer-aided detection (CAD software package SoftView™ 2.4A for bone suppression and OnGuard™ 5.2 (Riverain Technologies, Miamisburg, OH, USA for automated detection of pulmonary nodules in chest radiographs. Subjects and Methods: We retrospectively evaluated a dataset of 100 posteroanterior chest radiographs with pulmonary nodular lesions ranging from 5 to 85 mm. All nodules were confirmed with a consecutive computed tomography scan and histologically classified as 75% malignant. The number of detected lesions by observation in unprocessed images was compared to the number and dignity of CAD-detected lesions in bone-suppressed images (BSIs. Results: SoftView™ BSI does not affect the objective lesion-to-background contrast. OnGuard™ has a stand-alone sensitivity of 62% and specificity of 58% for nodular lesion detection in chest radiographs. The false positive rate is 0.88/image and the false negative (FN rate is 0.35/image. From the true positive lesions, 20% were proven benign and 80% were malignant. FN lesions were 47% benign and 53% malignant. Conclusion: We conclude that CAD does not qualify for a stand-alone standard of diagnosis. The use of CAD accompanied with a critical radiological assessment of the software suggested pattern appears more realistic. Accordingly, it is essential to focus on studies assessing the quality-time-cost profile of real-time (as opposed to retrospective CAD implementation in clinical diagnostics.

  16. Potential contribution of multiplanar reconstruction (MPR) to computer-aided detection of lung nodules on MDCT

    International Nuclear Information System (INIS)

    Matsumoto, Sumiaki; Ohno, Yoshiharu; Yamagata, Hitoshi; Nogami, Munenobu; Kono, Atsushi; Sugimura, Kazuro

    2012-01-01

    Purpose: To evaluate potential benefits of using multiplanar reconstruction (MPR) in computer-aided detection (CAD) of lung nodules on multidetector computed tomography (MDCT). Materials and methods: MDCT datasets of 60 patients with suspected lung nodules were retrospectively collected. Using “second-read” CAD, two radiologists (Readers 1 and 2) independently interpreted these datasets for the detection of non-calcified nodules (≥4 mm) with concomitant confidence rating. They did this task twice, first without MPR (using only axial images), and then 4 weeks later with MPR (using also coronal and sagittal MPR images), where the total reading time per dataset, including the time taken to assess the detection results of CAD software (CAD assessment time), was recorded. The total reading time and CAD assessment time without MPR and those with MPR were statistically compared for each reader. The radiologists’ performance for detecting nodules without MPR and the performance with MPR were compared using jackknife free-response receiver operating characteristic (JAFROC) analysis. Results: Compared to the CAD assessment time without MPR (mean, 69 s and 57 s for Readers 1 and 2), the CAD assessment time with MPR (mean, 46 s and 45 s for Readers 1 and 2) was significantly reduced (P < 0.001). For Reader 1, the total reading time was also significantly shorter in the case with MPR. There was no significant difference between the detection performances without MPR and with MPR. Conclusion: The use of MPR has the potential to improve the workflow in CAD of lung nodules on MDCT.

  17. Computer-aided diagnosis workstation and database system for chest diagnosis based on multi-helical CT images

    Science.gov (United States)

    Satoh, Hitoshi; Niki, Noboru; Mori, Kiyoshi; Eguchi, Kenji; Kaneko, Masahiro; Kakinuma, Ryutarou; Moriyama, Noriyuki; Ohmatsu, Hironobu; Masuda, Hideo; Machida, Suguru; Sasagawa, Michizou

    2006-03-01

    Multi-helical CT scanner advanced remarkably at the speed at which the chest CT images were acquired for mass screening. Mass screening based on multi-helical CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. To overcome this problem, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images and a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification. We also have developed electronic medical recording system and prototype internet system for the community health in two or more regions by using the Virtual Private Network router and Biometric fingerprint authentication system and Biometric face authentication system for safety of medical information. Based on these diagnostic assistance methods, we have now developed a new computer-aided workstation and database that can display suspected lesions three-dimensionally in a short time. This paper describes basic studies that have been conducted to evaluate this new system. The results of this study indicate that our computer-aided diagnosis workstation and network system can increase diagnostic speed, diagnostic accuracy and safety of medical information.

  18. Call for a Computer-Aided Cancer Detection and Classification Research Initiative in Oman.

    Science.gov (United States)

    Mirzal, Andri; Chaudhry, Shafique Ahmad

    2016-01-01

    Cancer is a major health problem in Oman. It is reported that cancer incidence in Oman is the second highest after Saudi Arabia among Gulf Cooperation Council countries. Based on GLOBOCAN estimates, Oman is predicted to face an almost two-fold increase in cancer incidence in the period 2008-2020. However, cancer research in Oman is still in its infancy. This is due to the fact that medical institutions and infrastructure that play central roles in data collection and analysis are relatively new developments in Oman. We believe the country requires an organized plan and efforts to promote local cancer research. In this paper, we discuss current research progress in cancer diagnosis using machine learning techniques to optimize computer aided cancer detection and classification (CAD). We specifically discuss CAD using two major medical data, i.e., medical imaging and microarray gene expression profiling, because medical imaging like mammography, MRI, and PET have been widely used in Oman for assisting radiologists in early cancer diagnosis and microarray data have been proven to be a reliable source for differential diagnosis. We also discuss future cancer research directions and benefits to Oman economy for entering the cancer research and treatment business as it is a multi-billion dollar industry worldwide.

  19. Computer aided detection of ureteral stones in thin slice computed tomography volumes using Convolutional Neural Networks.

    Science.gov (United States)

    Längkvist, Martin; Jendeberg, Johan; Thunberg, Per; Loutfi, Amy; Lidén, Mats

    2018-06-01

    Computed tomography (CT) is the method of choice for diagnosing ureteral stones - kidney stones that obstruct the ureter. The purpose of this study is to develop a computer aided detection (CAD) algorithm for identifying a ureteral stone in thin slice CT volumes. The challenge in CAD for urinary stones lies in the similarity in shape and intensity of stones with non-stone structures and how to efficiently deal with large high-resolution CT volumes. We address these challenges by using a Convolutional Neural Network (CNN) that works directly on the high resolution CT volumes. The method is evaluated on a large data base of 465 clinically acquired high-resolution CT volumes of the urinary tract with labeling of ureteral stones performed by a radiologist. The best model using 2.5D input data and anatomical information achieved a sensitivity of 100% and an average of 2.68 false-positives per patient on a test set of 88 scans. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Computer-aided instruction system; Systeme d'enseignement programme par ordinateur

    Energy Technology Data Exchange (ETDEWEB)

    Teneze, Jean Claude

    1968-12-18

    This research thesis addresses the use of teleprocessing and time sharing by the RAX IBM system and the possibility to introduce a dialog with the machine to develop an application in which the computer plays the role of a teacher for different pupils at the same time. Two operating modes are thus exploited: a teacher-mode and a pupil-mode. The developed CAI (computer-aided instruction) system comprises a checker to check the course syntax in teacher-mode, a translator to trans-code the course written in teacher-mode into a form which can be processes by the execution programme, and the execution programme which presents the course in pupil-mode.

  1. Clinical evaluation of a computer-aided diagnosis (CAD) prototype for the detection of pulmonary embolism.

    Science.gov (United States)

    Buhmann, Sonja; Herzog, Peter; Liang, Jin; Wolf, Mathias; Salganicoff, Marcos; Kirchhoff, Chlodwig; Reiser, Maximilian; Becker, Christoph H

    2007-06-01

    To evaluate the performance of a prototype computer-aided diagnosis (CAD) tool using artificial intelligence techniques for the detection of pulmonary embolism (PE) and the possible benefit for general radiologists. Forty multidetector row computed tomography datasets (16/64- channel scanner) using 100 kVp, 100 mAs effective/slice, and 1-mm axial reformats in a low-frequency reconstruction kernel were evaluated. A total of 80 mL iodinated contrast material was injected at a flow rate of 5 mL/seconds. Primarily, six general radiologists marked any PE using a commercially available lung evaluation software with simultaneous, automatic processing by CAD in the background. An expert panel consisting of two chest radiologists analyzed all PE marks from the readers and CAD, also searching for additional finding primarily missed by both, forming the ground truth. The ground truth consisted of 212 emboli. Of these, 65 (31%) were centrally and 147 (69%) were peripherally located. The readers detected 157/212 emboli (74%) leading to a sensitivity of 97% (63/65) for central and 70% (103/147) for peripheral emboli with 9 false-positive findings. CAD detected 168/212 emboli (79%), reaching a sensitivity of 74% for central (48/65) and 82%(120/147) for peripheral emboli. A total of 154 CAD candidates were considered as false positives, yielding an average of 3.85 false positives/case. The CAD software showed a sensitivity comparable to that of the general radiologists, but with more false positives. CAD detection of findings incremental to the radiologists suggests benefit when used as a second reader. Future versions of CAD have the potential to further increase clinical benefit by improving sensitivity and reducing false marks.

  2. Computer-aided detection of prostate cancer in T2-weighted MRI within the peripheral zone

    Science.gov (United States)

    Rampun, Andrik; Zheng, Ling; Malcolm, Paul; Tiddeman, Bernie; Zwiggelaar, Reyer

    2016-07-01

    In this paper we propose a prostate cancer computer-aided diagnosis (CAD) system and suggest a set of discriminant texture descriptors extracted from T2-weighted MRI data which can be used as a good basis for a multimodality system. For this purpose, 215 texture descriptors were extracted and eleven different classifiers were employed to achieve the best possible results. The proposed method was tested based on 418 T2-weighted MR images taken from 45 patients and evaluated using 9-fold cross validation with five patients in each fold. The results demonstrated comparable results to existing CAD systems using multimodality MRI. We achieved an area under the receiver operating curve (A z ) values equal to 90.0%+/- 7.6% , 89.5%+/- 8.9% , 87.9%+/- 9.3% and 87.4%+/- 9.2% for Bayesian networks, ADTree, random forest and multilayer perceptron classifiers, respectively, while a meta-voting classifier using average probability as a combination rule achieved 92.7%+/- 7.4% .

  3. Development of a computer-aided digital reactivity computer system for PWRs

    International Nuclear Information System (INIS)

    Chung, S.-K.; Sung, K.-Y.; Kim, D.; Cho, D.-Y.

    1993-01-01

    Reactor physics tests at initial startup and after reloading are performed to verify nuclear design and to ensure safety operation. Two kinds of reactivity computers, analog and digital, have been widely used in the pressurized water reactor (PWR) core physics test. The test data of both reactivity computers are displayed only on the strip chart recorder, and these data are managed by hand so that the accuracy of the test results depends on operator expertise and experiences. This paper describes the development of the computer-aided digital reactivity computer system (DRCS), which is enhanced by system management software and an improved system for the application of the PWR core physics test

  4. Computer-aided software understanding systems to enhance confidence of scientific codes

    International Nuclear Information System (INIS)

    Sheng, G.; Oeren, T.I.

    1991-01-01

    A unique characteristic of nuclear waste disposal is the very long time span over which the combined engineered and natural containment system must remain effective: hundreds of thousands of years. Since there is no precedent in human history for such an endeavour, simulation with the use of computers is the only means we have of forecasting possible future outcomes quantitatively. The need for reliable models and software to make such forecasts so far into the future is obvious. One of the critical elements necessary to ensure reliability is the degree of reviewability of the computer program. Among others, there are two very important reasons for this. Firstly, if there is to be any chance at all of validating the conceptual models as implemented by the computer code, peer reviewers must be able to see and understand what the program is doing. It is all but impossible to achieve this understanding by just looking at the code due to possible unfamiliarity with the language and often due as well to the length and complexity of the code. Secondly, a thorough understanding of the code is also necessary to carry out code maintenance activities which include among others, error detection, error correction and code modification for purposes of enhancing its performance, functionality or to adapt it to a changed environment. The emerging concepts of computer-aided software understanding and reverse engineering can answer precisely these needs. This paper will discuss the role they can play in enhancing the confidence one has on computer codes and several examples will be provided. Finally a brief discussion of combining state-of-art forward engineering systems with reverse engineering systems will show how powerfully they can contribute to the overall quality assurance of a computer program. (13 refs., 7 figs.)

  5. Performance of computer-aided detection in false-negative screening mammograms of breast cancers

    International Nuclear Information System (INIS)

    Han, Boo Kyung; Kim, Ji Young; Shin, Jung Hee; Choe, Yeon Hyeon

    2004-01-01

    To analyze retrospectively the abnormalities visible on the false-negative screening mammograms of patients with breast cancer and to determine the performance of computer-aided detection (CAD) in the detection of cancers. Of 108 consecutive cases of breast cancer diagnosed over a period of 6 years, of which previous screening mammograms were available, 32 retrospectively visible abnormalities (at which locations cancer later developed) were found in the previous mammograms, and which were originally reported as negative. These 32 patients ranged in age from 38 to 72 years (mean 52 years). We analyzed their previous mammographic findings, and assessed the ability of CAD to mark cancers in previous mammograms, according to the clinical presentation, the type of abnormalities and the mammographic parenchymal density. In these 32 previous mammograms of breast cancers (20 asymptomatic, 12 symptomatic), the retrospectively visible abnormalities were identified as densities in 22, calcifications in 8, and densities with calcifications in 2. CAD marked abnormalities in 20 (63%) of the 32 cancers with false-negative screening mammograms; 14 (70%) of the 20 subsequent screening-detected cancers, 5 (50%) of the 10 interval cancers, and 1 (50%) of the 2 cancers palpable after the screening interval. CAD marked 12 (50%) of the 24 densities and 9 (90%) of the 10 calcifications. CAD marked abnormalities in 7 (50%) of the 14 predominantly fatty breasts, and 13 (72%) of the 18 dense breasts. CAD-assisted diagnosis could potentially decrease the number of false-negative mammograms caused by the failure to recognize the cancer in the screening program, although its usefulness in the prevention of interval cancers appears to be limited

  6. A new approach to develop computer-aided detection schemes of digital mammograms

    Science.gov (United States)

    Tan, Maxine; Qian, Wei; Pu, Jiantao; Liu, Hong; Zheng, Bin

    2015-06-01

    The purpose of this study is to develop a new global mammographic image feature analysis based computer-aided detection (CAD) scheme and evaluate its performance in detecting positive screening mammography examinations. A dataset that includes images acquired from 1896 full-field digital mammography (FFDM) screening examinations was used in this study. Among them, 812 cases were positive for cancer and 1084 were negative or benign. After segmenting the breast area, a computerized scheme was applied to compute 92 global mammographic tissue density based features on each of four mammograms of the craniocaudal (CC) and mediolateral oblique (MLO) views. After adding three existing popular risk factors (woman’s age, subjectively rated mammographic density, and family breast cancer history) into the initial feature pool, we applied a sequential forward floating selection feature selection algorithm to select relevant features from the bilateral CC and MLO view images separately. The selected CC and MLO view image features were used to train two artificial neural networks (ANNs). The results were then fused by a third ANN to build a two-stage classifier to predict the likelihood of the FFDM screening examination being positive. CAD performance was tested using a ten-fold cross-validation method. The computed area under the receiver operating characteristic curve was AUC = 0.779   ±   0.025 and the odds ratio monotonically increased from 1 to 31.55 as CAD-generated detection scores increased. The study demonstrated that this new global image feature based CAD scheme had a relatively higher discriminatory power to cue the FFDM examinations with high risk of being positive, which may provide a new CAD-cueing method to assist radiologists in reading and interpreting screening mammograms.

  7. The efficacy of using computer-aided detection (CAD) for detection of breast cancer in mammography screening

    DEFF Research Database (Denmark)

    Henriksen, Emilie L; Carlsen, Jonathan F; Vejborg, Ilse Mm

    2018-01-01

    Background Early detection of breast cancer (BC) is crucial in lowering the mortality. Purpose To present an overview of studies concerning computer-aided detection (CAD) in screening mammography for early detection of BC and compare diagnostic accuracy and recall rates (RR) of single reading (SR......) with SR + CAD and double reading (DR) with SR + CAD. Material and Methods PRISMA guidelines were used as a review protocol. Articles on clinical trials concerning CAD for detection of BC in a screening population were included. The literature search resulted in 1522 records. A total of 1491 records were...... excluded by abstract and 18 were excluded by full text reading. A total of 13 articles were included. Results All but two studies from the SR vs. SR + CAD group showed an increased sensitivity and/or cancer detection rate (CDR) when adding CAD. The DR vs. SR + CAD group showed no significant differences...

  8. Computer-aided system for diabetes care in Berlin, G.D.R.

    Science.gov (United States)

    Thoelke, H; Meusel, K; Ratzmann, K P

    1990-01-01

    In the Centre of Diabetes and Metabolic Disorders of Berlin, G.D.R., a computer-aided care system has been used since 1974, aiming at relieving physicians and medical staff from routine tasks and rendering possible epidemiological research on an unselected diabetes population of a defined area. The basis of the system is the data bank on diabetics (DB), where at present data from approximately 55,000 patients are stored. DB is used as a diabetes register of Berlin. On the basis of standardised criteria of diagnosis and therapy of diabetes mellitus in our dispensary care system, DB facilitates representative epidemiological analyses of the diabetic population, e.g. prevalence, incidence, duration of diabetes, and modes of treatment. The availability of general data on the population or the selection of specified groups of patients serves the management of the care system. Also, it supports the computer-aided recall of type II diabetics, treated either with diet alone or with diet and oral drugs. In this way, the standardised evaluation of treatment strategies in large populations of diabetics is possible on the basis of uniform metabolic criteria (blood glucose plus urinary glucose). The system consists of a main computer in the data processing unit and of personal computers in the diabetes centre which can be used either individually or as terminals to the main computer. During 14 years of experience, the computer-aided out-patient care of type II diabetics has proved efficient in a big-city area with a large population.

  9. Computer-aided detection of pulmonary nodules: a comparative study using the public LIDC/IDRI database

    International Nuclear Information System (INIS)

    Jacobs, Colin; Prokop, Mathias; Rikxoort, Eva M. van; Ginneken, Bram van; Murphy, Keelin; Schaefer-Prokop, Cornelia M.

    2016-01-01

    To benchmark the performance of state-of-the-art computer-aided detection (CAD) of pulmonary nodules using the largest publicly available annotated CT database (LIDC/IDRI), and to show that CAD finds lesions not identified by the LIDC's four-fold double reading process. The LIDC/IDRI database contains 888 thoracic CT scans with a section thickness of 2.5 mm or lower. We report performance of two commercial and one academic CAD system. The influence of presence of contrast, section thickness, and reconstruction kernel on CAD performance was assessed. Four radiologists independently analyzed the false positive CAD marks of the best CAD system. The updated commercial CAD system showed the best performance with a sensitivity of 82 % at an average of 3.1 false positive detections per scan. Forty-five false positive CAD marks were scored as nodules by all four radiologists in our study. On the largest publicly available reference database for lung nodule detection in chest CT, the updated commercial CAD system locates the vast majority of pulmonary nodules at a low false positive rate. Potential for CAD is substantiated by the fact that it identifies pulmonary nodules that were not marked during the extensive four-fold LIDC annotation process. (orig.)

  10. Computer-aided detection of renal calculi from noncontrast CT images using TV-flow and MSER features

    Science.gov (United States)

    Liu, Jianfei; Wang, Shijun; Turkbey, Evrim B.; Linguraru, Marius George; Yao, Jianhua; Summers, Ronald M.

    2015-01-01

    Purpose: Renal calculi are common extracolonic incidental findings on computed tomographic colonography (CTC). This work aims to develop a fully automated computer-aided diagnosis system to accurately detect renal calculi on CTC images. Methods: The authors developed a total variation (TV) flow method to reduce image noise within the kidneys while maintaining the characteristic appearance of renal calculi. Maximally stable extremal region (MSER) features were then calculated to robustly identify calculi candidates. Finally, the authors computed texture and shape features that were imported to support vector machines for calculus classification. The method was validated on a dataset of 192 patients and compared to a baseline approach that detects calculi by thresholding. The authors also compared their method with the detection approaches using anisotropic diffusion and nonsmoothing. Results: At a false positive rate of 8 per patient, the sensitivities of the new method and the baseline thresholding approach were 69% and 35% (p < 1e − 3) on all calculi from 1 to 433 mm3 in the testing dataset. The sensitivities of the detection methods using anisotropic diffusion and nonsmoothing were 36% and 0%, respectively. The sensitivity of the new method increased to 90% if only larger and more clinically relevant calculi were considered. Conclusions: Experimental results demonstrated that TV-flow and MSER features are efficient means to robustly and accurately detect renal calculi on low-dose, high noise CTC images. Thus, the proposed method can potentially improve diagnosis. PMID:25563255

  11. Max-AUC feature selection in computer-aided detection of polyps in CT colonography.

    Science.gov (United States)

    Xu, Jian-Wu; Suzuki, Kenji

    2014-03-01

    We propose a feature selection method based on a sequential forward floating selection (SFFS) procedure to improve the performance of a classifier in computerized detection of polyps in CT colonography (CTC). The feature selection method is coupled with a nonlinear support vector machine (SVM) classifier. Unlike the conventional linear method based on Wilks' lambda, the proposed method selected the most relevant features that would maximize the area under the receiver operating characteristic curve (AUC), which directly maximizes classification performance, evaluated based on AUC value, in the computer-aided detection (CADe) scheme. We presented two variants of the proposed method with different stopping criteria used in the SFFS procedure. The first variant searched all feature combinations allowed in the SFFS procedure and selected the subsets that maximize the AUC values. The second variant performed a statistical test at each step during the SFFS procedure, and it was terminated if the increase in the AUC value was not statistically significant. The advantage of the second variant is its lower computational cost. To test the performance of the proposed method, we compared it against the popular stepwise feature selection method based on Wilks' lambda for a colonic-polyp database (25 polyps and 2624 nonpolyps). We extracted 75 morphologic, gray-level-based, and texture features from the segmented lesion candidate regions. The two variants of the proposed feature selection method chose 29 and 7 features, respectively. Two SVM classifiers trained with these selected features yielded a 96% by-polyp sensitivity at false-positive (FP) rates of 4.1 and 6.5 per patient, respectively. Experiments showed a significant improvement in the performance of the classifier with the proposed feature selection method over that with the popular stepwise feature selection based on Wilks' lambda that yielded 18.0 FPs per patient at the same sensitivity level.

  12. Computer-Aided System of Virtual Testing of Gas Turbine Engines

    Directory of Open Access Journals (Sweden)

    Rybakov Viktor N.

    2016-01-01

    Full Text Available The article describes the concept of a virtual lab that includes subsystem of gas turbine engine simulation, subsystem of experiment planning, subsystem of measurement errors simulation, subsystem of simulator identification and others. The basis for virtual lab development is the computer-aided system of thermogasdynamic research and analysis “ASTRA”. The features of gas turbine engine transient modes simulator are described. The principal difference between the simulators of transient and stationary modes of gas turbine engines is that the energy balance of the compressor and turbine becomes not applicable. The computer-aided system of virtual gas turbine engine testing was created using the developed transient modes simulator. This system solves the tasks of operational (throttling, speed, climatic, altitude characteristics calculation, analysis of transient dynamics and selection of optimal control laws. Besides, the system of virtual gas turbine engine testing is a clear demonstration of gas turbine engine working process and the regularities of engine elements collaboration. The interface of the system of virtual gas turbine engine testing is described in the article and some screenshots of the interface elements are provided. The developed system of virtual gas turbine engine testing provides means for reducing the laboriousness of gas turbine engines testing. Besides, the implementation of this system in the learning process allows the diversification of lab works and therefore improve the quality of training.

  13. Identification and red blood cell automated counting from blood smear images using computer-aided system.

    Science.gov (United States)

    Acharya, Vasundhara; Kumar, Preetham

    2018-03-01

    Red blood cell count plays a vital role in identifying the overall health of the patient. Hospitals use the hemocytometer to count the blood cells. Conventional method of placing the smear under microscope and counting the cells manually lead to erroneous results, and medical laboratory technicians are put under stress. A computer-aided system will help to attain precise results in less amount of time. This research work proposes an image-processing technique for counting the number of red blood cells. It aims to examine and process the blood smear image, in order to support the counting of red blood cells and identify the number of normal and abnormal cells in the image automatically. K-medoids algorithm which is robust to external noise is used to extract the WBCs from the image. Granulometric analysis is used to separate the red blood cells from the white blood cells. The red blood cells obtained are counted using the labeling algorithm and circular Hough transform. The radius range for the circle-drawing algorithm is estimated by computing the distance of the pixels from the boundary which automates the entire algorithm. A comparison is done between the counts obtained using the labeling algorithm and circular Hough transform. Results of the work showed that circular Hough transform was more accurate in counting the red blood cells than the labeling algorithm as it was successful in identifying even the overlapping cells. The work also intends to compare the results of cell count done using the proposed methodology and manual approach. The work is designed to address all the drawbacks of the previous research work. The research work can be extended to extract various texture and shape features of abnormal cells identified so that diseases like anemia of inflammation and chronic disease can be detected at the earliest.

  14. Automatic bone detection and soft tissue aware ultrasound-CT registration for computer-aided orthopedic surgery.

    Science.gov (United States)

    Wein, Wolfgang; Karamalis, Athanasios; Baumgartner, Adrian; Navab, Nassir

    2015-06-01

    The transfer of preoperative CT data into the tracking system coordinates within an operating room is of high interest for computer-aided orthopedic surgery. In this work, we introduce a solution for intra-operative ultrasound-CT registration of bones. We have developed methods for fully automatic real-time bone detection in ultrasound images and global automatic registration to CT. The bone detection algorithm uses a novel bone-specific feature descriptor and was thoroughly evaluated on both in-vivo and ex-vivo data. A global optimization strategy aligns the bone surface, followed by a soft tissue aware intensity-based registration to provide higher local registration accuracy. We evaluated the system on femur, tibia and fibula anatomy in a cadaver study with human legs, where magnetically tracked bone markers were implanted to yield ground truth information. An overall median system error of 3.7 mm was achieved on 11 datasets. Global and fully automatic registration of bones aquired with ultrasound to CT is feasible, with bone detection and tracking operating in real time for immediate feedback to the surgeon.

  15. Computer-aided detection of small pulmonary nodules in multidetector spiral computed tomography (MSCT) in children

    International Nuclear Information System (INIS)

    Honnef, D.; Behrendt, F.F.; Hohl, C.; Mahnken, A.H.; Guenther, R.W.; Das, M.; Mertens, R.; Stanzel, S.

    2008-01-01

    Purpose: Retrospective evaluation of computer-aided detection software (CAD) for automated detection (LungCAD, Siemens Medical solutions, Forchheim, Germany) and volumetry (LungCARE) of pulmonary nodules in dose-reduced pediatric MDCT. Materials and Methods: 30 scans of 24 children (10.4±5.9 years, 13 girls, 11 boys, 39.7±29.3 kg body weight) were performed on a 16-MDCT for tumor staging (n=18), inflammation (n=9), other indications (n=3). Tube voltage 120 kVp and effective mAs were adapted to body weight. Slice thickness 2 mm, increment 1 mm. A pediatric radiologist (U1), a CAD expert (U2) and an inexperienced radiologist (U3) independently analyzed the lung window images without and with the CAD as a second reader. In a consensus decision U1 and U2 were the reference standard. Results: Five examinations had to be excluded from the study due to other underlying lung disease. A total of 24 pulmonary nodules were found in all data sets with a minimal diameter of 0.35 mm to 3.81 mm (mean 1.7±0.85 mm). The sensitivities were as follows: U1 95.8% and 100% with CAD; U2 91.7% U3 66.7%. U2 and U3 did not detect further nodules with CAD. The sensitivity of CAD alone was 41.7% with 0.32 false-positive findings per examination. Interobserver agreement between U1/U2 regarding nodule detection with CAD was good (k=0.6500) and without CAD very good (k=0.8727). For the rest (U1/U3; U2/U3 with and without CAD), it was weak (k=0.0667-0.1884). Depending on the measured value (axial measurement, volume), there is a significant correlation (p=0.0026-0.0432) between nodule size and CAD detection. Undetected pulmonary nodules (mean 1.35 mm; range 0.35-2.61 mm) were smaller than the detected ones (mean 2.19 mm; range 1.35-3.81 mm). No significant correlation was found between CAD findings and patient age (p=0.9263) and body weight (p=0.9271) as well as nodule location (subpleural, intraparenchymal; p=1.0) and noise/SNR. (orig.)

  16. Computer-aided structure elucidation Pt. 3. Extended version of assigner system

    Energy Technology Data Exchange (ETDEWEB)

    Szalontai, G; Csapo, Z; Recsey, Zs [Nehezvegyipari Kutato Intezet, Veszprem (Hungary)

    1982-01-01

    Computer-aided interpretation of /sup 13/C-NMR, /sup 1/H-NMR and IR spectra of organic molecules (M.W.<=500) has been performed by an artificial intelligence approach. A procedure for the joint /sup 13/C-NMR - /sup 1/H-NMR - IR spectrum interpretation is outlined. Possible ways of finding acceptable greater fragments on the basis of /sup 1/H-NMR - /sup 13/C-NMR data and of /sup 13/C-NMR data alone are also described. Detailed examples are given to demonstrate the capability of the system.

  17. Development of computer-aided auto-ranging technique for a computed radiography system

    International Nuclear Information System (INIS)

    Ishida, M.; Shimura, K.; Nakajima, N.; Kato, H.

    1988-01-01

    For a computed radiography system, the authors developed a computer-aided autoranging technique in which the clinically useful image data are automatically mapped to the available display range. The preread image data are inspected to determine the location of collimation. A histogram of the pixels inside the collimation is evaluated regarding characteristic values such as maxima and minima, and then the optimal density and contrast are derived for the display image. The effect of the autoranging technique was investigated at several hospitals in Japan. The average rate of films lost due to undesirable density or contrast was about 0.5%

  18. Computer-aided detection of lung nodules on chest CT: issues to be solved before clinical use

    International Nuclear Information System (INIS)

    Goo, Jin Mo

    2005-01-01

    Given the increasing resolution of modern CT scanners, and the requirements for large-scale lung-screening examinations and diagnostic studies, there is an increased need for the accurate and reproducible analysis of the large number of images. Nodule detection is one of the main challenges of CT imaging, as they can be missed due to their small size, low relative contrast, or because they are located in an area with complex anatomy. Recent developments in computer-aided diagnosis (CAD) schemes are expected to aid radiologists in various tasks of chest imaging. In this era of multidetector row CT, the thoracic applications of greatest interest include the detection and volume measurement of lung nodules (1-7). Technology for CAD as applied to lung nodule detection on chest CT has been approved by the Food and Drug Administration and is currently commercially available. The article by Lee et al. (5) in this issue of the Korean Journal of Radiology is one of the few studies to examine the influence of a commercially available CAD system on the detection of lung nodules. In this study, some additional nodules were detected with the help of a CAD system, but at the expense of increased false positivity. The nodule detection rate of the CAD system in this study was lower than that achieved by radiologist, and the authors insist that the CAD system should be improved further. Compared to the use of CAD on mammograms, CAD evaluations of chest CTs remain limited to the laboratory setting. In this field, apart from the issues of detection rate and false positive detections, many obstacles must be overcome before CAD can be used in a true clinical reading environment. In this editorial, I will list some of these issues, but I emphasize now that I believe these issues will be solved by improved CAD versions in the near future

  19. Computer-aided detection of masses in full-field digital mammography using screen-film mammograms for training

    International Nuclear Information System (INIS)

    Kallenberg, Michiel; Karssemeijer, Nico

    2008-01-01

    It would be of great value when available databases of screen-film mammography (SFM) images can be used to train full-field digital mammography (FFDM) computer-aided detection (CAD) systems, as compilation of new databases is costly. In this paper, we investigate this possibility. Firstly, we develop a method that converts an FFDM image into an SFM-like representation. In this conversion method, we establish a relation between exposure and optical density by simulation of an automatic exposure control unit. Secondly, we investigate the effects of using the SFM images as training samples compared to training with FFDM images. Our FFDM database consisted of 266 cases, of which 102 were biopsy-proven malignant masses and 164 normals. The images were acquired with systems of two different manufacturers. We found that, when we trained our FFDM CAD system with a small number of images, training with FFDM images, using a five-fold crossvalidation procedure, outperformed training with SFM images. However, when the full SFM database, consisting of 348 abnormal cases (including 204 priors) and 810 normal cases, was used for training, SFM training outperformed FFDMA training. These results show that an existing CAD system for detection of masses in SFM can be used for FFDM images without retraining.

  20. Development and evaluation of a computer-aided system for analyzing human error in railway operations

    International Nuclear Information System (INIS)

    Kim, Dong San; Baek, Dong Hyun; Yoon, Wan Chul

    2010-01-01

    As human error has been recognized as one of the major contributors to accidents in safety-critical systems, there has been a strong need for techniques that can analyze human error effectively. Although many techniques have been developed so far, much room for improvement remains. As human error analysis is a cognitively demanding and time-consuming task, it is particularly necessary to develop a computerized system supporting this task. This paper presents a computer-aided system for analyzing human error in railway operations, called Computer-Aided System for Human Error Analysis and Reduction (CAS-HEAR). It supports analysts to find multiple levels of error causes and their causal relations by using predefined links between contextual factors and causal factors as well as links between causal factors. In addition, it is based on a complete accident model; hence, it helps analysts to conduct a thorough analysis without missing any important part of human error analysis. A prototype of CAS-HEAR was evaluated by nine field investigators from six railway organizations in Korea. Its overall usefulness in human error analysis was confirmed, although development of its simplified version and some modification of the contextual factors and causal factors are required in order to ensure its practical use.

  1. Computer-aided load monitoring system for nuclear power plant steel framing structures

    International Nuclear Information System (INIS)

    Skaczylo, A.T.; Fung, S-J; Hooks, R.W.

    1984-01-01

    The design of nuclear power plant steel framing structures is a long and involved process. It is often complicated by numerous changes in design loads as a result of additions, deletions and modifications of HVAC hangers, cable tray hangers, electric conduit hangers, and small bore and large bore mechanical component supports. Manual tracking of load changes of thousands of supports and their impact to the structural steel design adequacy is very time-consuming and is susceptible to errors. This paper presents a computer-aided load monitoring system using the latest technology of data base management and interactive computer software. By linking the data base to analysis and investigation computer programs, the engineer has a very powerful tool to monitor not only the load revisions but also their impact on the steel structural floor framing members and connections. Links to reporting programs allow quick information retrieval in the form of comprehensive reports. Drawing programs extract data from the data base to draw hanger load system drawings on a computer-aided drafting system. These capabilities allow engineers to minimize modifications by strategically locating new hangers or rearranging auxiliary steel configuration

  2. Accuracy evaluation of metal copings fabricated by computer-aided milling and direct metal laser sintering systems.

    Science.gov (United States)

    Park, Jong-Kyoung; Lee, Wan-Sun; Kim, Hae-Young; Kim, Woong-Chul; Kim, Ji-Hwan

    2015-04-01

    To assess the marginal and internal gaps of the copings fabricated by computer-aided milling and direct metal laser sintering (DMLS) systems in comparison to casting method. Ten metal copings were fabricated by casting, computer-aided milling, and DMLS. Seven mesiodistal and labiolingual positions were then measured, and each of these were divided into the categories; marginal gap (MG), cervical gap (CG), axial wall at internal gap (AG), and incisal edge at internal gap (IG). Evaluation was performed by a silicone replica technique. A digital microscope was used for measurement of silicone layer. Statistical analyses included one-way and repeated measure ANOVA to test the difference between the fabrication methods and categories of measured points (α=.05), respectively. The mean gap differed significantly with fabrication methods (P<.001). Casting produced the narrowest gap in each of the four measured positions, whereas CG, AG, and IG proved narrower in computer-aided milling than in DMLS. Thus, with the exception of MG, all positions exhibited a significant difference between computer-aided milling and DMLS (P<.05). Although the gap was found to vary with fabrication methods, the marginal and internal gaps of the copings fabricated by computer-aided milling and DMLS fell within the range of clinical acceptance (<120 µm). However, the statistically significant difference to conventional casting indicates that the gaps in computer-aided milling and DMLS fabricated restorations still need to be further reduced.

  3. Second Asia-Pacific Conference on the Computer Aided System Engineering

    CERN Document Server

    Chaczko, Zenon; Jacak, Witold; Łuba, Tadeusz; Computational Intelligence and Efficiency in Engineering Systems

    2015-01-01

    This carefully edited and reviewed volume addresses the increasingly popular demand for seeking more clarity in the data that we are immersed in. It offers excellent examples of the intelligent ubiquitous computation, as well as recent advances in systems engineering and informatics. The content represents state-of-the-art foundations for researchers in the domain of modern computation, computer science, system engineering and networking, with many examples that are set in industrial application context. The book includes the carefully selected best contributions to APCASE 2014, the 2nd Asia-Pacific Conference on  Computer Aided System Engineering, held February 10-12, 2014 in South Kuta, Bali, Indonesia. The book consists of four main parts that cover data-oriented engineering science research in a wide range of applications: computational models and knowledge discovery; communications networks and cloud computing; computer-based systems; and data-oriented and software-intensive systems.

  4. Clinical application of low-dose CT combined with computer-aided detection in lung cancer screening

    International Nuclear Information System (INIS)

    Xu Zushan; Hou Hongjun; Xu Yan; Ma Daqing

    2010-01-01

    Objective: To investigate the clinical value of chest low-dose CT (LDCT) combined with computer-aided detection (CAD) system for lung cancer screening in high risk population. Methods: Two hundred and nineteen healthy candidates underwent 64-slice LDCT scan. All images were reviewed in consensus by two radiologists with 15 years of thoracic CT diagnosis experience. Then the image data were analyzed with CAD alone. Finally images were reviewed by two radiologists with 5 years of CT diagnosis experience with and without CT Viewer software. The sensitivity, false positive rate of CAD for pulmonary nodule detection were calculated. SPSS 11.5 software and Chi-square test were used for the statistics. Results: Of 219 candidates ,104(47.5% ) were detected with lung nodules. There were 366 true nodules confirmed by the senior radiologists. The CAD system detected 271 (74.0%) true nodules and 424 false-positive nodules. The false-positive rate was 1.94/per case. The two junior radiologists indentifid 292 (79.8%), 286(78.1%) nodules without CAD and 336 (91.8%), 333 (91.0%) nodules with CAD respectively. There were significant differences for radiologists in indentifying nodules with or without CAD system (P<0.01). Conclusions: CAD is more sensitive than radiologists for indentifying the nodules in the central area or in the hilar region of the lung. While radiologists are more sensitive for the peripheral and sub-pleural nodules,or ground glass opacity nodules, or nodules smaller than 4 mm. CAD can not be used alone. The detection rate can be improved with the combination of radiologist and CAD in LDCT screen. (authors)

  5. Computer-aided stress analysis system for nuclear plant primary components

    International Nuclear Information System (INIS)

    Murai, Tsutomu; Tokumaru, Yoshio; Yamazaki, Junko.

    1980-06-01

    Generally it needs a vast quantity of calculation to make the stress analysis reports of nuclear plant primary components. In Japan, especially, stress analysis reports are under obligation to make for each plant. In Mitsubishi Heavy Industries, Ltd., We have been making great efforts to rationalize the process of analysis for about these ten years. As the result of rationalization up to now, a computer-aided stress analysis system using graphic display, graphic tablet, data file, etc. was accomplished and it needs us only the least hand work. In addition we developed a fracture safety analysis system. And we are going to develop the input generator system for 3-dimensional FEM analysis by graphics terminals in the near future. We expect that when the above-mentioned input generator system is accomplished, it will be possible for us to solve instantly any case of problem. (author)

  6. Computer-aided design model for anaerobic-phased-solids digester system

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z.; Zhang, R. [University of California, Davis, CA (United States); Tiangco, V. [California Energy Commission, Sacramento, CA (United States)

    1999-07-01

    The anaerobic-phased-solids (APS) digester system is a newly developed anaerobic digestion system for converting solid wastes, such as crop residues and food wastes, into biogas for power and heat generation. A computer-aided engineering design model has been developed to design the APS-digester system and study the heat transfer from the reactors and energy production of the system. Simulation results of a case study are presented by using the model to predict the heating energy requirement and biogas energy production for anaerobic digestion of garlic waste. The important factors, such as environmental conditions, insulation properties, and characteristics of the wastes, on net energy production are also investigated. (author)

  7. Automated image-based colon cleansing for laxative-free CT colonography computer-aided polyp detection

    International Nuclear Information System (INIS)

    Linguraru, Marius George; Panjwani, Neil; Fletcher, Joel G.; Summer, Ronald M.

    2011-01-01

    Purpose: To evaluate the performance of a computer-aided detection (CAD) system for detecting colonic polyps at noncathartic computed tomography colonography (CTC) in conjunction with an automated image-based colon cleansing algorithm. Methods: An automated colon cleansing algorithm was designed to detect and subtract tagged-stool, accounting for heterogeneity and poor tagging, to be used in conjunction with a colon CAD system. The method is locally adaptive and combines intensity, shape, and texture analysis with probabilistic optimization. CTC data from cathartic-free bowel preparation were acquired for testing and training the parameters. Patients underwent various colonic preparations with barium or Gastroview in divided doses over 48 h before scanning. No laxatives were administered and no dietary modifications were required. Cases were selected from a polyp-enriched cohort and included scans in which at least 90% of the solid stool was visually estimated to be tagged and each colonic segment was distended in either the prone or supine view. The CAD system was run comparatively with and without the stool subtraction algorithm. Results: The dataset comprised 38 CTC scans from prone and/or supine scans of 19 patients containing 44 polyps larger than 10 mm (22 unique polyps, if matched between prone and supine scans). The results are robust on fine details around folds, thin-stool linings on the colonic wall, near polyps and in large fluid/stool pools. The sensitivity of the CAD system is 70.5% per polyp at a rate of 5.75 false positives/scan without using the stool subtraction module. This detection improved significantly (p = 0.009) after automated colon cleansing on cathartic-free data to 86.4% true positive rate at 5.75 false positives/scan. Conclusions: An automated image-based colon cleansing algorithm designed to overcome the challenges of the noncathartic colon significantly improves the sensitivity of colon CAD by approximately 15%.

  8. Development of computer-aided design system of elastic sensitive elements of automatic metering devices

    Science.gov (United States)

    Kalinkina, M. E.; Kozlov, A. S.; Labkovskaia, R. I.; Pirozhnikova, O. I.; Tkalich, V. L.; Shmakov, N. A.

    2018-05-01

    The object of research is the element base of devices of control and automation systems, including in its composition annular elastic sensitive elements, methods of their modeling, calculation algorithms and software complexes for automation of their design processes. The article is devoted to the development of the computer-aided design system of elastic sensitive elements used in weight- and force-measuring automation devices. Based on the mathematical modeling of deformation processes in a solid, as well as the results of static and dynamic analysis, the calculation of elastic elements is given using the capabilities of modern software systems based on numerical simulation. In the course of the simulation, the model was a divided hexagonal grid of finite elements with a maximum size not exceeding 2.5 mm. The results of modal and dynamic analysis are presented in this article.

  9. A computer-aided diagnostic and troubleshooting system for fuel cell power plants

    International Nuclear Information System (INIS)

    Unkle, C.R.

    1990-10-01

    This Interactive Computer-Aided Troubleshooting System (ICATS) was designed as a troubleshooting aid for the Tokyo Electric Power Company (TEPCO) 11-megawatt dc Module (DCM). ICATS represents an integration of the System Testability and Maintenance Program (STAMP reg-sign) and the Portable Interactive Troubleshooter (POINTER trademark) software packages developed by ARINC Research Corporation. ICATS was designed to aid in the fault isolation of shutdown conditions that may occur in the DCM during on-load operations and start-up, and hold conditions that may occur during start-up. ICATS may also be used to help fault-isolate a return-to-standby condition occurring from on-load operation of the DCM. This report describes the development of ICATS and the ICATS functional design. The unique features of STAMP and POINTER, which allow for diagnostic aids to be designed for systems not yet built and operating, are also described. 10 refs., 21 figs., 6 tabs

  10. Control-C and ACSL for computer-aided control systems engineering

    International Nuclear Information System (INIS)

    Schrick, B.; Anex, R.

    1986-01-01

    A computer-aided engineering package, called CTRL-C, provides an easy-to-use work-bench for the analysis and design of multivariable systems. ACSL, a powerful simulation language, complements CTRL-C and provides a flexible evaluation tool. Combined, the CTRL-C/ACSL package is an interaction environment with a comprehensive set of tools for analysis, design, simulation, and evaluation. A unified software system is possible for engineering analysis and presentation. Recognizing that no software can satisfy all needs, Ctrl-C provides consistent and flexible communication with the operating system and other software, most especially ACSL. CTRL-C and ACSL demonstrate that an interactive environment can be a powerful, accessible, and extensible tool for engineering

  11. Computer aided design

    International Nuclear Information System (INIS)

    Barache, J.M.; Beltranda, G.; Blanc, P.

    1987-01-01

    In order to ensure that the data transmitted to the managment system is of the required quality and consistent with the general control command protocols, computer aided design (CAD) was employed for level N4. One describes the use of CAD for the control system of N4 [fr

  12. Computer-Aided Detection in Digital Mammography: False-Positive Marks and Their Reproducibility in Negative Mammograms

    International Nuclear Information System (INIS)

    Kim, Seung Ja; Moon, Woo Kyung; Cho, Nariya; Chang, Jung Min; Seong, Min Hyun

    2009-01-01

    Background: There are relatively few studies reporting the frequency of false-positive computer-aided detection (CAD) marks and their reproducibility in normal cases. Purpose: To evaluate retrospectively the false-positive mark rate of a CAD system and the reproducibility of false-positive marks in two sets of negative digital mammograms. Material and Methods: Two sets of negative digital mammograms were obtained in 360 women (mean age 57 years, range 30-76 years) with an approximate interval of 1 year (mean time 343.7 days), and a CAD system was applied. False-positive CAD marks and the reproducibility were determined. Results: Of the 360 patients, 252 (70.0%) and 240 (66.7%) patients had 1-7 CAD marks on the initial and second mammograms, respectively. The false-positive CAD mark rate was 1.5 (1.1 for masses and 0.4 for calcifications) and 1.4 (1.0 for masses and 0.4 for calcifications) per examination in the initial and second mammograms, respectively. The reproducibility of the false-positive CAD marks was 12.0% for both mass (81/680) and microcalcification (33/278) marks. Conclusion: False-positive CAD marks were seen in approximately 70% of normal cases. However, the reproducibility was very low. Radiologists must be familiar with the findings of false-positive CAD marks, since they are very common and can increase the recall rate in screening

  13. A practical technique for benefit-cost analysis of computer-aided design and drafting systems

    International Nuclear Information System (INIS)

    Shah, R.R.; Yan, G.

    1979-03-01

    Analysis of benefits and costs associated with the operation of Computer-Aided Design and Drafting Systems (CADDS) are needed to derive economic justification for acquiring new systems, as well as to evaluate the performance of existing installations. In practice, however, such analyses are difficult to perform since most technical and economic advantages of CADDS are ΣirreduciblesΣ, i.e. cannot be readily translated into monetary terms. In this paper, a practical technique for economic analysis of CADDS in a drawing office environment is presented. A Σworst caseΣ approach is taken since increase in productivity of existing manpower is the only benefit considered, while all foreseen costs are taken into account. Methods of estimating benefits and costs are described. The procedure for performing the analysis is illustrated by a case study based on the drawing office activities at Atomic Energy of Canada Limited. (auth)

  14. Evaluation of the efficiency of computer-aided spectra search systems based on information theory

    International Nuclear Information System (INIS)

    Schaarschmidt, K.

    1979-01-01

    Application of information theory allows objective evaluation of the efficiency of computer-aided spectra search systems. For this purpose, a significant number of search processes must be analyzed. The amount of information gained by computer application is considered as the difference between the entropy of the data bank and a conditional entropy depending on the proportion of unsuccessful search processes and ballast. The influence of the following factors can be estimated: volume, structure, and quality of the spectra collection stored, efficiency of the encoding instruction and the comparing algorithm, and subjective errors involved in the encoding of spectra. The relations derived are applied to two published storage and retrieval systems for infared spectra. (Auth.)

  15. Towards Building a Computer Aided Education System for Special Students Using Wearable Sensor Technologies

    Directory of Open Access Journals (Sweden)

    Raja Majid Mehmood

    2017-02-01

    Full Text Available Human computer interaction is a growing field in terms of helping people in their daily life to improve their living. Especially, people with some disability may need an interface which is more appropriate and compatible with their needs. Our research is focused on similar kinds of problems, such as students with some mental disorder or mood disruption problems. To improve their learning process, an intelligent emotion recognition system is essential which has an ability to recognize the current emotional state of the brain. Nowadays, in special schools, instructors are commonly use some conventional methods for managing special students for educational purposes. In this paper, we proposed a novel computer aided method for instructors at special schools where they can teach special students with the support of our system using wearable technologies.

  16. Computer-aided design of microvasculature systems for use in vascular scaffold production

    Energy Technology Data Exchange (ETDEWEB)

    Mondy, William Lafayette [Department of Chemical and Biomedical Engineering, University of South Florida, FL (United States); Cameron, Don [Department of Pathology and Cell Biology, College of Medicine, University of South Florida, FL (United States); Timmermans, Jean-Pierre [Department of Veterinary Sciences, University of Antwerp (Belgium); De Clerck, Nora [Department of Biomedical Sciences University of Antwerp (Belgium); Sasov, Alexander [Skyscan (Belgium); Casteleyn, Christophe [College of Veterinary Medicine, Ghent University (Belgium); Piegl, Les A [Department of Computer Science and Engineering, University of South Florida, FL (United States)

    2009-09-15

    In vitro biomedical engineering of intact, functional vascular networks, which include capillary structures, is a prerequisite for adequate vascular scaffold production. Capillary structures are necessary since they provide the elements and compounds for the growth, function and maintenance of 3D tissue structures. Computer-aided modeling of stereolithographic (STL) micro-computer tomographic (micro-CT) 3D models is a technique that enables us to mimic the design of vascular tree systems containing capillary beds, found in tissues. In our first paper (Mondy et al 2009 Tissue Eng. at press), using micro-CT, we studied the possibility of using vascular tissues to produce data capable of aiding the design of vascular tree scaffolding, which would help in the reverse engineering of a complete vascular tree system including capillary bed structures. In this paper, we used STL models of large datasets of computer-aided design (CAD) data of vascular structures which contained capillary structures that mimic those in the dermal layers of rabbit skin. Using CAD software we created from 3D STL models a bio-CAD design for the development of capillary-containing vascular tree scaffolding for skin. This method is designed to enhance a variety of therapeutic protocols including, but not limited to, organ and tissue repair, systemic disease mediation and cell/tissue transplantation therapy. Our successful approach to in vitro vasculogenesis will allow the bioengineering of various other types of 3D tissue structures, and as such greatly expands the potential applications of biomedical engineering technology into the fields of biomedical research and medicine.

  17. Computer-aided design of microvasculature systems for use in vascular scaffold production

    International Nuclear Information System (INIS)

    Mondy, William Lafayette; Cameron, Don; Timmermans, Jean-Pierre; De Clerck, Nora; Sasov, Alexander; Casteleyn, Christophe; Piegl, Les A

    2009-01-01

    In vitro biomedical engineering of intact, functional vascular networks, which include capillary structures, is a prerequisite for adequate vascular scaffold production. Capillary structures are necessary since they provide the elements and compounds for the growth, function and maintenance of 3D tissue structures. Computer-aided modeling of stereolithographic (STL) micro-computer tomographic (micro-CT) 3D models is a technique that enables us to mimic the design of vascular tree systems containing capillary beds, found in tissues. In our first paper (Mondy et al 2009 Tissue Eng. at press), using micro-CT, we studied the possibility of using vascular tissues to produce data capable of aiding the design of vascular tree scaffolding, which would help in the reverse engineering of a complete vascular tree system including capillary bed structures. In this paper, we used STL models of large datasets of computer-aided design (CAD) data of vascular structures which contained capillary structures that mimic those in the dermal layers of rabbit skin. Using CAD software we created from 3D STL models a bio-CAD design for the development of capillary-containing vascular tree scaffolding for skin. This method is designed to enhance a variety of therapeutic protocols including, but not limited to, organ and tissue repair, systemic disease mediation and cell/tissue transplantation therapy. Our successful approach to in vitro vasculogenesis will allow the bioengineering of various other types of 3D tissue structures, and as such greatly expands the potential applications of biomedical engineering technology into the fields of biomedical research and medicine.

  18. Computer-aided design of microvasculature systems for use in vascular scaffold production.

    Science.gov (United States)

    Mondy, William Lafayette; Cameron, Don; Timmermans, Jean-Pierre; De Clerck, Nora; Sasov, Alexander; Casteleyn, Christophe; Piegl, Les A

    2009-09-01

    In vitro biomedical engineering of intact, functional vascular networks, which include capillary structures, is a prerequisite for adequate vascular scaffold production. Capillary structures are necessary since they provide the elements and compounds for the growth, function and maintenance of 3D tissue structures. Computer-aided modeling of stereolithographic (STL) micro-computer tomographic (micro-CT) 3D models is a technique that enables us to mimic the design of vascular tree systems containing capillary beds, found in tissues. In our first paper (Mondy et al 2009 Tissue Eng. at press), using micro-CT, we studied the possibility of using vascular tissues to produce data capable of aiding the design of vascular tree scaffolding, which would help in the reverse engineering of a complete vascular tree system including capillary bed structures. In this paper, we used STL models of large datasets of computer-aided design (CAD) data of vascular structures which contained capillary structures that mimic those in the dermal layers of rabbit skin. Using CAD software we created from 3D STL models a bio-CAD design for the development of capillary-containing vascular tree scaffolding for skin. This method is designed to enhance a variety of therapeutic protocols including, but not limited to, organ and tissue repair, systemic disease mediation and cell/tissue transplantation therapy. Our successful approach to in vitro vasculogenesis will allow the bioengineering of various other types of 3D tissue structures, and as such greatly expands the potential applications of biomedical engineering technology into the fields of biomedical research and medicine.

  19. Computer-aided detection in computed tomography colonography. Current status and problems with detection of early colorectal cancer

    International Nuclear Information System (INIS)

    Morimoto, Tsuyoshi; Nakijima, Yasuo; Iinuma, Gen; Arai, Yasuaki; Shiraishi, Junji; Moriyama, Noriyuki; Beddoe, G.

    2008-01-01

    The aim of this study was to evaluate the usefulness of computer-aided detection (CAD) in diagnosing early colorectal cancer using computed tomography colonography (CTC). A total of 30 CTC data sets for 30 early colorectal cancers in 30 patients were retrospectively reviewed by three radiologists. After primary evaluation, a second reading was performed using CAD findings. The readers evaluated each colorectal segment for the presence or absence of colorectal cancer using five confidence rating levels. To compare the assessment results, the sensitivity and specificity with and without CAD were calculated on the basis of the confidence rating, and differences in these variables were analyzed by receiver operating characteristic (ROC) analysis. The average sensitivities for the detection without and with CAD for the three readers were 81.6% and 75.6%, respectively. Among the three readers, only one reader improved sensitivity with CAD compared to that without. CAD decreased specificity in all three readers. CAD detected 100% of protruding lesions but only 69.2% of flat lesions. On ROC analysis, the diagnostic performance of all three readers was decreased by use of CAD. Currently available CAD with CTC does not improve diagnostic performance for detecting early colorectal cancer. An improved CAD algorithm is required for detecting fiat lesions and reducing the false-positive rate. (author)

  20. Development of COMPAS, computer aided process flowsheet design and analysis system of nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    Homma, Shunji; Sakamoto, Susumu; Takanashi, Mitsuhiro; Nammo, Akihiko; Satoh, Yoshihiro; Soejima, Takayuki; Koga, Jiro; Matsumoto, Shiro

    1995-01-01

    A computer aided process flowsheet design and analysis system, COMPAS has been developed in order to carry out the flowsheet calculation on the process flow diagram of nuclear fuel reprocessing. All of equipments, such as dissolver, mixer-settler, and so on, in the process flowsheet diagram are graphically visualized as icon on a bitmap display of UNIX workstation. Drawing of a flowsheet can be carried out easily by the mouse operation. Not only a published numerical simulation code but also a user's original one can be used on the COMPAS. Specifications of the equipment and the concentration of components in the stream displayed as tables can be edited by a computer user. Results of calculation can be also displayed graphically. Two examples show that the COMPAS is applicable to decide operating conditions of Purex process and to analyze extraction behavior in a mixer-settler extractor. (author)

  1. Computer aided system for segmentation and visualization of microcalcifications in digital mammograms

    International Nuclear Information System (INIS)

    Reljin, B.; Reljin, I.; Milosevic, Z.; Stojic, T.

    2009-01-01

    Two methods for segmentation and visualization of microcalcifications in digital or digitized mammograms are described. First method is based on modern mathematical morphology, while the second one uses the multifractal approach. In the first method, by using an appropriate combination of some morphological operations, high local contrast enhancement, followed by significant suppression of background tissue, irrespective of its radiology density, is obtained. By iterative procedure, this method highly emphasizes only small bright details, possible microcalcifications. In a multifractal approach, from initial mammogram image, a corresponding multifractal 'images' are created, from which a radiologist has a freedom to change the level of segmentation. An appropriate user friendly computer aided visualization (CAV) system with embedded two methods is realized. The interactive approach enables the physician to control the level and the quality of segmentation. Suggested methods were tested through mammograms from MIAS database as a gold standard, and from clinical praxis, using digitized films and digital images from full field digital mammograph. (authors)

  2. Computer-aided diagnosis system for bone scintigrams from Japanese patients: importance of training database

    DEFF Research Database (Denmark)

    Horikoshi, Hiroyuki; Kikuchi, Akihiro; Onoguchi, Masahisa

    2012-01-01

    higher performance than the corresponding CAD software trained with a European database for the analysis of bone scans from Japanese patients. These results could at least partly be caused by the physical differences between Japanese and European patients resulting in less influence of attenuation......Computer-aided diagnosis (CAD) software for bone scintigrams have recently been introduced as a clinical quality assurance tool. The purpose of this study was to compare the diagnostic accuracy of two CAD systems, one based on a European and one on a Japanese training database, in a group of bone...... scans from Japanese patients.The two CAD software are trained to interpret bone scans using training databases consisting of bone scans with the desired interpretation, metastatic disease or not. One software was trained using 795 bone scans from European patients and the other with 904 bone scans from...

  3. Performance of computer-aided diagnosis for detection of lacunar infarcts on brain MR images: ROC analysis of radiologists' detection

    International Nuclear Information System (INIS)

    Uchiyama, Y.; Yokoyama, R.; Hara, T.; Fujita, H.; Asano, T.; Kato, H.; Hoshi, H.; Yamakawa, H.; Iwama, T.; Ando, H.; Yamakawa, H.

    2007-01-01

    The detection and management of asymptomatic lacunar infarcts on magnetic resonance (MR) images are important tasks for radiologists to ensure the prevention of sever cerebral infarctions. However, accurate identification of lacunar infarcts is a difficult. Therefore, we developed a computer-aided diagnosis (CAD) scheme for detection of lacunar infarcts. The purpose of this study was to evaluate radiologists' performance in detection of lacunar infarcts without and with use of CAD scheme. 30 T1- and 30 T2- weighted images obtained from 30 patients were used for an observer study, which were consisted of 15 cases with a single lacunar infarct and 15 cases without any lacunar infarct. Six radiologists participated in the observer study. They interpreted lacunar infarcts first without and then with use of the scheme. For all six observers, average area under the receiver operating characteristic curve value was increased from 0.920 to 0.965 when they used the computer output. This CAD scheme might have the potential to improve the accuracy of radiologists' performance in the detection of lacunar infarcts on MR images. (orig.)

  4. A new 2D segmentation method based on dynamic programming applied to computer aided detection in mammography

    International Nuclear Information System (INIS)

    Timp, Sheila; Karssemeijer, Nico

    2004-01-01

    Mass segmentation plays a crucial role in computer-aided diagnosis (CAD) systems for classification of suspicious regions as normal, benign, or malignant. In this article we present a robust and automated segmentation technique--based on dynamic programming--to segment mass lesions from surrounding tissue. In addition, we propose an efficient algorithm to guarantee resulting contours to be closed. The segmentation method based on dynamic programming was quantitatively compared with two other automated segmentation methods (region growing and the discrete contour model) on a dataset of 1210 masses. For each mass an overlap criterion was calculated to determine the similarity with manual segmentation. The mean overlap percentage for dynamic programming was 0.69, for the other two methods 0.60 and 0.59, respectively. The difference in overlap percentage was statistically significant. To study the influence of the segmentation method on the performance of a CAD system two additional experiments were carried out. The first experiment studied the detection performance of the CAD system for the different segmentation methods. Free-response receiver operating characteristics analysis showed that the detection performance was nearly identical for the three segmentation methods. In the second experiment the ability of the classifier to discriminate between malignant and benign lesions was studied. For region based evaluation the area A z under the receiver operating characteristics curve was 0.74 for dynamic programming, 0.72 for the discrete contour model, and 0.67 for region growing. The difference in A z values obtained by the dynamic programming method and region growing was statistically significant. The differences between other methods were not significant

  5. Multi-site evaluation of a computer aided detection (CAD) algorithm for small acute intra-cranial hemorrhage and development of a stand-alone CAD system ready for deployment in a clinical environment

    Science.gov (United States)

    Deshpande, Ruchi R.; Fernandez, James; Lee, Joon K.; Chan, Tao; Liu, Brent J.; Huang, H. K.

    2010-03-01

    Timely detection of Acute Intra-cranial Hemorrhage (AIH) in an emergency environment is essential for the triage of patients suffering from Traumatic Brain Injury. Moreover, the small size of lesions and lack of experience on the reader's part could lead to difficulties in the detection of AIH. A CT based CAD algorithm for the detection of AIH has been developed in order to improve upon the current standard of identification and treatment of AIH. A retrospective analysis of the algorithm has already been carried out with 135 AIH CT studies with 135 matched normal head CT studies from the Los Angeles County General Hospital/ University of Southern California Hospital System (LAC/USC). In the next step, AIH studies have been collected from Walter Reed Army Medical Center, and are currently being processed using the AIH CAD system as part of implementing a multi-site assessment and evaluation of the performance of the algorithm. The sensitivity and specificity numbers from the Walter Reed study will be compared with the numbers from the LAC/USC study to determine if there are differences in the presentation and detection due to the difference in the nature of trauma between the two sites. Simultaneously, a stand-alone system with a user friendly GUI has been developed to facilitate implementation in a clinical setting.

  6. A Computer-Aided Diagnosis System for Breast Cancer Combining Digital Mammography and Genomics

    Science.gov (United States)

    2006-05-01

    Huang, "Breast cancer diagnosis using self-organizing map for sonography." Ultrasound Med. Biol. 26, 405 (2000). 20 K. Horsch, M.L. Giger, L.A. Venta ...L.A. Venta , "Performance of computer-aided diagnosis in the interpretation of lesions on breast sonography." Acad Radiol 11, 272 (2004). 22 W. Chen...418. 27. Horsch K, Giger ML, Vyborny CJ, Venta LA. Performance of computer-aided diagnosis in the interpretation of lesions on breast sonography

  7. Development of computer-aided design and production system for nuclear power plant

    International Nuclear Information System (INIS)

    Ishii, Masanori

    1983-01-01

    The technically required matters related to the design and production of nuclear power stations tended to increase from the viewpoint of the safety and reliability, and it is indispensable to cope with such technically required matters skillfully for the rationalization of the design and production and for the construction of highly reliable plants. Ishikawajima Harima Heavy Industries Co., Ltd., has developed the computer-aided design data information and engineering system which performs dialogue type design and drawing, and as the result, the design-production consistent system is developed to do stress analysis, production design, production management and the output of data for numerically controlled machine tools consistently. In this paper, mainly the consistent system in the field of plant design centering around piping and also the computer system for the design of vessels and others are outlined. The features of the design works for nuclear power plants, the rationalization of the design and production management of piping and vessels, and the application of the CAD system to other general equipment and improvement works are reported. This system is the powerful means to meet the requirement of heightening quality and reducing cost. (Kako, I.)

  8. Computer-Aided Modelling and Analysis of PV Systems: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Charalambos Koukouvaos

    2014-01-01

    Full Text Available Modern scientific advances have enabled remarkable efficacy for photovoltaic systems with regard to the exploitation of solar energy, boosting them into having a rapidly growing position among the systems developed for the production of renewable energy. However, in many cases the design, analysis, and control of photovoltaic systems are tasks which are quite complex and thus difficult to be carried out. In order to cope with this kind of problems, appropriate software tools have been developed either as standalone products or parts of general purpose software platforms used to model and simulate the generation, transmission, and distribution of solar energy. The utilization of this kind of software tools may be extremely helpful to the successful performance evaluation of energy systems with maximum accuracy and minimum cost in time and effort. The work presented in this paper aims on a first level at the performance analysis of various configurations of photovoltaic systems through computer-aided modelling. On a second level, it provides a comparative evaluation of the credibility of two of the most advanced graphical programming environments, namely, Simulink and LabVIEW, with regard to their application in photovoltaic systems.

  9. Image formation simulation for computer-aided inspection planning of machine vision systems

    Science.gov (United States)

    Irgenfried, Stephan; Bergmann, Stephan; Mohammadikaji, Mahsa; Beyerer, Jürgen; Dachsbacher, Carsten; Wörn, Heinz

    2017-06-01

    In this work, a simulation toolset for Computer Aided Inspection Planning (CAIP) of systems for automated optical inspection (AOI) is presented along with a versatile two-robot-setup for verification of simulation and system planning results. The toolset helps to narrow down the large design space of optical inspection systems in interaction with a system expert. The image formation taking place in optical inspection systems is simulated using GPU-based real time graphics and high quality off-line-rendering. The simulation pipeline allows a stepwise optimization of the system, from fast evaluation of surface patch visibility based on real time graphics up to evaluation of image processing results based on off-line global illumination calculation. A focus of this work is on the dependency of simulation quality on measuring, modeling and parameterizing the optical surface properties of the object to be inspected. The applicability to real world problems is demonstrated by taking the example of planning a 3D laser scanner application. Qualitative and quantitative comparison results of synthetic and real images are presented.

  10. Computer-aided bone age assessment for ethnically diverse older children using integrated fuzzy logic system

    Science.gov (United States)

    Ma, Kevin; Moin, Paymann; Zhang, Aifeng; Liu, Brent

    2010-03-01

    Bone Age Assessment (BAA) of children is a clinical procedure frequently performed in pediatric radiology to evaluate the stage of skeletal maturation based on the left hand x-ray radiograph. The current BAA standard in the US is using the Greulich & Pyle (G&P) Hand Atlas, which was developed fifty years ago and was only based on Caucasian population from the Midwest US. To bring the BAA procedure up-to-date with today's population, a Digital Hand Atlas (DHA) consisting of 1400 hand images of normal children of different ethnicities, age, and gender. Based on the DHA and to solve inter- and intra-observer reading discrepancies, an automatic computer-aided bone age assessment system has been developed and tested in clinical environments. The algorithm utilizes features extracted from three regions of interests: phalanges, carpal, and radius. The features are aggregated into a fuzzy logic system, which outputs the calculated bone age. The previous BAA system only uses features from phalanges and carpal, thus BAA result for children over age of 15 is less accurate. In this project, the new radius features are incorporated into the overall BAA system. The bone age results, calculated from the new fuzzy logic system, are compared against radiologists' readings based on G&P atlas, and exhibits an improvement in reading accuracy for older children.

  11. Computer aided process planning system based on workflow technology and integrated bill of material tree

    Institute of Scientific and Technical Information of China (English)

    LU Chun-guang; MENG Li-li

    2006-01-01

    It is extremely important for procedure of process design and management of process data for product life cycle in Computer Aided Process Planning (CAPP) system,but there are many shortcomings with traditional CAPP system in these respects.To solve these questions,application of workflow technology in CAPP system based on web-integrated Bill of Material (BOM) tree is discussed,and a concept of integrated BOM tree was brought forward.Taking integrated BOM as the thread,CAPP systematic technological process is analyzed.The function,system architecture,and implementation mechanism of CAPP system based on Browser/Server and Customer/Server model are expatiated.Based on it,the key technologies of workflow management device were analyzed.Eventually,the implementation mechanism of integrated BOM tree was analyzed from viewpoints of material information encoding,organization node design of integrated BOM tree,transformation from Engineering BOM (EBOM)to Process BOM (PBOM),and the programming implementation technology.

  12. The efficacy of using computer-aided detection (CAD) for detection of breast cancer in mammography screening: a systematic review.

    Science.gov (United States)

    Henriksen, Emilie L; Carlsen, Jonathan F; Vejborg, Ilse Mm; Nielsen, Michael B; Lauridsen, Carsten A

    2018-01-01

    Background Early detection of breast cancer (BC) is crucial in lowering the mortality. Purpose To present an overview of studies concerning computer-aided detection (CAD) in screening mammography for early detection of BC and compare diagnostic accuracy and recall rates (RR) of single reading (SR) with SR + CAD and double reading (DR) with SR + CAD. Material and Methods PRISMA guidelines were used as a review protocol. Articles on clinical trials concerning CAD for detection of BC in a screening population were included. The literature search resulted in 1522 records. A total of 1491 records were excluded by abstract and 18 were excluded by full text reading. A total of 13 articles were included. Results All but two studies from the SR vs. SR + CAD group showed an increased sensitivity and/or cancer detection rate (CDR) when adding CAD. The DR vs. SR + CAD group showed no significant differences in sensitivity and CDR. Adding CAD to SR increased the RR and decreased the specificity in all but one study. For the DR vs. SR + CAD group only one study reported a significant difference in RR. Conclusion All but two studies showed an increase in RR, sensitivity and CDR when adding CAD to SR. Compared to DR no statistically significant differences in sensitivity or CDR were reported. Additional studies based on organized population-based screening programs, with longer follow-up time, high-volume readers, and digital mammography are needed to evaluate the efficacy of CAD.

  13. Development of a Computer-aided Learning System for Graphical Analysis of Continuous-Time Control Systems

    Directory of Open Access Journals (Sweden)

    J. F. Opadiji

    2010-06-01

    Full Text Available We present the development and deployment process of a computer-aided learning tool which serves as a training aid for undergraduate control engineering courses. We show the process of algorithm construction and implementation of the software which is also aimed at teaching software development at undergraduate level. The scope of this project is limited to graphical analysis of continuous-time control systems.

  14. Computer-aided design of control systems to meet many requirements

    Science.gov (United States)

    Schy, A. A.; Adams, W. M., Jr.; Johnson, K. G.

    1974-01-01

    A method is described for using nonlinear programing in the computer-aided design of airplane control systems. It is assumed that the quality of such systems depends on many criteria. These criteria are included in the constraints vector (instead of attempting to combine them into a single scalar criterion, as is usually done), and the design proceeds through a sequence of nonlinear programing solutions in which the designer varies the specification of sets of requirements levels. The method is applied to design of a lateral stability augmentation system (SAS) for a fighter airplane, in which the requirements vector is chosen from the official handling qualities specifications. Results are shown for several simple SAS configurations designed to obtain desirable handling qualities over all design flight conditions with minimum feedback gains. The choice of the final design for each case is not unique but depends on the designer's decision as to which achievable set of requirements levels represents the best for that system. Results indicate that it may be possible to design constant parameter SAS which can satisfy the most stringent handling qualities requirements for fighter airplanes in all flight conditions. The role of the designer as a decision maker, interacting with the computer program, is discussed. Advantages of this type of designer-computer interaction are emphasized. Desirable extensions of the method are indicated.

  15. Web-based computer-aided-diagnosis (CAD) system for bone age assessment (BAA) of children

    Science.gov (United States)

    Zhang, Aifeng; Uyeda, Joshua; Tsao, Sinchai; Ma, Kevin; Vachon, Linda A.; Liu, Brent J.; Huang, H. K.

    2008-03-01

    Bone age assessment (BAA) of children is a clinical procedure frequently performed in pediatric radiology to evaluate the stage of skeletal maturation based on a left hand and wrist radiograph. The most commonly used standard: Greulich and Pyle (G&P) Hand Atlas was developed 50 years ago and exclusively based on Caucasian population. Moreover, inter- & intra-observer discrepancies using this method create a need of an objective and automatic BAA method. A digital hand atlas (DHA) has been collected with 1,400 hand images of normal children from Asian, African American, Caucasian and Hispanic descends. Based on DHA, a fully automatic, objective computer-aided-diagnosis (CAD) method was developed and it was adapted to specific population. To bring DHA and CAD method to the clinical environment as a useful tool in assisting radiologist to achieve higher accuracy in BAA, a web-based system with direct connection to a clinical site is designed as a novel clinical implementation approach for online and real time BAA. The core of the system, a CAD server receives the image from clinical site, processes it by the CAD method and finally, generates report. A web service publishes the results and radiologists at the clinical site can review it online within minutes. This prototype can be easily extended to multiple clinical sites and will provide the foundation for broader use of the CAD system for BAA.

  16. MVPACK: a computer-aided design tool for multivariable control systems

    International Nuclear Information System (INIS)

    Mensah, S.; Frketich, G.

    1985-10-01

    The design and analysis of high-performance controllers for complex plants require a collection of interactive, powerful computer software. MVPACK, an open-ended package for the computer-aided design of control systems, has been developed in the Reactor Control Branch of the Chalk River Nuclear Laboratories. The package is fully interactive and includes a comprehensive state-of-the-art mathematical library to support development of complex, multivariable, control algorithms. Coded in RATFOR, MVPACK is portable with minimal changes. It operates with a flexible data structure which makes efficient use of minicomputer resources and provides a standard framework for program generation. The existence of a help mechanism enhances the simplicity of package utilization. This paper provides a brief tutorial overview of the package. It reviews the specifications used in the design and implementation of the package and briefly describes the database structure, supporting libraries and some design and analysis modules of MVPACK. Several application examples to illustrate the capability of the package are given. Experience with MVPACK shows that the package provides a synergistic environment for the design of control and regulation systems, and that it is a unique tool for training of control system engineers

  17. MVPACK: a package for the computer-aided design of multivariable control systems

    International Nuclear Information System (INIS)

    Mensah, S.

    1984-01-01

    The design and analysis of high performing controllers for large complex plants require a collection of interactive, powerful computer software. MVPACK, an open-ended package for the computer aided design of control systems has been developed in the Reactor Control Branch of the Chalk River Nuclear Laboratories. The package is fully interactive, and includes a comprehensive state-of-the-art mathematical library to support development of complex multivariable control algorithms. Coded in RATFOR, MVPACK operates with a flexible data structure which makes efficient use of minicomputer resources and provides a standard framework for program generation. The existence of a help mechanism enhances the simplicity of package utilization. This report provides the technical description of the package. It reviews the specifications used in the design and implementation of the package. The database structure, the supporting libraries and the design and analysis modules of MVPACK are described. The report includes several application examples to illustrate the capability of the package. Experience with MVPACK shows that the package provides a synergistic environment for control and regulation systems design, and that it is a unique tool in training of control system engineers

  18. Computer aided analysis of prostate histopathology images to support a refined Gleason grading system

    Science.gov (United States)

    Ren, Jian; Sadimin, Evita; Foran, David J.; Qi, Xin

    2017-02-01

    The Gleason grading system used to render prostate cancer diagnosis has recently been updated to allow more accurate grade stratification and higher prognostic discrimination when compared to the traditional grading system. In spite of progress made in trying to standardize the grading process, there still remains approximately a 30% grading discrepancy between the score rendered by general pathologists and those provided by experts while reviewing needle biopsies for Gleason pattern 3 and 4, which accounts for more than 70% of daily prostate tis- sue slides at most institutions. We propose a new computational imaging method for Gleason pattern 3 and 4 classification, which better matches the newly established prostate cancer grading system. The computer- aided analysis method includes two phases. First, the boundary of each glandular region is automatically segmented using a deep convolutional neural network. Second, color, shape and texture features are extracted from superpixels corresponding to the outer and inner glandular regions and are subsequently forwarded to a random forest classifier to give a gradient score between 3 and 4 for each delineated glandular region. The F1 score for glandular segmentation is 0.8460 and the classification accuracy is 0.83+/-0.03.

  19. High School Students' Written Argumentation Qualities with Problem-Based Computer-Aided Material (PBCAM) Designed about Human Endocrine System

    Science.gov (United States)

    Vekli, Gülsah Sezen; Çimer, Atilla

    2017-01-01

    This study investigated development of students' scientific argumentation levels in the applications made with Problem-Based Computer-Aided Material (PBCAM) designed about Human Endocrine System. The case study method was used: The study group was formed of 43 students in the 11th grade of the science high school in Rize. Human Endocrine System…

  20. CADDS [Computer-aided Drafting and Design System] brings quality and precision to the Canadian Maple [research reactor

    International Nuclear Information System (INIS)

    Goland, D.

    1989-01-01

    Atomic Energy of Canada Ltd (AECL) has found that using the ''intelligent'' Computer-Aided Drafting and Design System (CADDS) helped address design problems at an early stage and led to productivity gains of around 50 per cent. Other bonuses were the quality and precision of the designs and documents produced. Its application to the MAPLE research reactor project is described. (author)

  1. Computer Aided Analysis and Prototype Testing of an Improved Biogas Reactor For Biomass System

    Directory of Open Access Journals (Sweden)

    Jeremy (Zheng Li

    2015-05-01

    Full Text Available The alternative fuel resources substituting for conventional fuels are required due to less availability of fuel resources than demand in the market. A large amount of crude oil and petroleum products are required to be imported in many countries over the world. Also the environmental pollution is another serious problem when use petroleum products. Biogas, with the composition of 54.5% CH4, 39.5% CO2, and 6% other elements (i.e., H2, N2, H2S, and O2, is a clear green fuel that can substitute the regular petroleum fuels to reduce the pollutant elements. Biogas can be produced by performing enriching, scrubbing, and bottling processes. The purification process can be further applied to take away the pollutants in biogas. The pure biogas process analyzed in this research is compressed to 2950 psi while being filled into gas cylinder. The daily produced biogas capacity is around 5480 ft3 and the processing efficacy is affected by surrounding environment and other factors. The design and development of this biogas system is assisted through mathematical analysis, 3D modeling, computational simulation, and prototype testing. Both computer aided analysis and prototype testing show close results which validate the feasibility of this biogas system in biomass applications.

  2. Experience gained in using a computer-aided teaching system in Azov maritime institute

    Directory of Open Access Journals (Sweden)

    Олександр Миколайович Зиновченко

    2017-06-01

    Full Text Available Brief analysis of the known teaching methods through the use of computer has been given. Computer-aided teaching system includes an interactive lecture, laboratory works, an application for online testing and evaluation of the new knowledge assimilation and the software used by the teacher. The virtual lecture presents information as sound tracked dynamic pictures accompanied by permanent practical work that fixes the acquired knowledge in the student’s mind. Each teaching step in the virtual lecture is followed with practical work evaluated by the computer. Virtual labs make it possible to consolidate the new knowledge by practice. They provide for the individual activity of the student, monitor his progress and automatically evaluate his knowledge. These applications are installed in the student's computer. The computer applications of the teacher include a generator of the tests for testing and evaluation of the new knowledge, a typical problems base, personal information files generator for each student and a computer application forming the final mark of the student. The results of the testing of this teaching system show that it is efficient, making it possible to organize a flexible schedule of the educational process,cutting down the working hours of the teacher

  3. Computer-aided mass detection in mammography: False positive reduction via gray-scale invariant ranklet texture features

    International Nuclear Information System (INIS)

    Masotti, Matteo; Lanconelli, Nico; Campanini, Renato

    2009-01-01

    In this work, gray-scale invariant ranklet texture features are proposed for false positive reduction (FPR) in computer-aided detection (CAD) of breast masses. Two main considerations are at the basis of this proposal. First, false positive (FP) marks surviving our previous CAD system seem to be characterized by specific texture properties that can be used to discriminate them from masses. Second, our previous CAD system achieves invariance to linear/nonlinear monotonic gray-scale transformations by encoding regions of interest into ranklet images through the ranklet transform, an image transformation similar to the wavelet transform, yet dealing with pixels' ranks rather than with their gray-scale values. Therefore, the new FPR approach proposed herein defines a set of texture features which are calculated directly from the ranklet images corresponding to the regions of interest surviving our previous CAD system, hence, ranklet texture features; then, a support vector machine (SVM) classifier is used for discrimination. As a result of this approach, texture-based information is used to discriminate FP marks surviving our previous CAD system; at the same time, invariance to linear/nonlinear monotonic gray-scale transformations of the new CAD system is guaranteed, as ranklet texture features are calculated from ranklet images that have this property themselves by construction. To emphasize the gray-scale invariance of both the previous and new CAD systems, training and testing are carried out without any in-between parameters' adjustment on mammograms having different gray-scale dynamics; in particular, training is carried out on analog digitized mammograms taken from a publicly available digital database, whereas testing is performed on full-field digital mammograms taken from an in-house database. Free-response receiver operating characteristic (FROC) curve analysis of the two CAD systems demonstrates that the new approach achieves a higher reduction of FP marks

  4. Selection of examples in case-based computer-aided decision systems

    International Nuclear Information System (INIS)

    Mazurowski, Maciej A; Zurada, Jacek M; Tourassi, Georgia D

    2008-01-01

    Case-based computer-aided decision (CB-CAD) systems rely on a database of previously stored, known examples when classifying new, incoming queries. Such systems can be particularly useful since they do not need retraining every time a new example is deposited in the case base. The adaptive nature of case-based systems is well suited to the current trend of continuously expanding digital databases in the medical domain. To maintain efficiency, however, such systems need sophisticated strategies to effectively manage the available evidence database. In this paper, we discuss the general problem of building an evidence database by selecting the most useful examples to store while satisfying existing storage requirements. We evaluate three intelligent techniques for this purpose: genetic algorithm-based selection, greedy selection and random mutation hill climbing. These techniques are compared to a random selection strategy used as the baseline. The study is performed with a previously presented CB-CAD system applied for false positive reduction in screening mammograms. The experimental evaluation shows that when the development goal is to maximize the system's diagnostic performance, the intelligent techniques are able to reduce the size of the evidence database to 37% of the original database by eliminating superfluous and/or detrimental examples while at the same time significantly improving the CAD system's performance. Furthermore, if the case-base size is a main concern, the total number of examples stored in the system can be reduced to only 2-4% of the original database without a decrease in the diagnostic performance. Comparison of the techniques shows that random mutation hill climbing provides the best balance between the diagnostic performance and computational efficiency when building the evidence database of the CB-CAD system.

  5. Mobile Phone Based Falling Detection Sensor and Computer-Aided Algorithm for Elderly People

    Directory of Open Access Journals (Sweden)

    Lee Jong-Ha

    2016-01-01

    Full Text Available Falls are dangerous for the elderly population; therefore many fall detection systems have been developed. However, previous methods are bulky for elderly people or only use a single sensor to isolate falls from daily living activities, which makes a fall difficult to distinguish. In this paper, we present a cost-effective and easy-to-use portable fall-detection sensor and algorithm. Specifically, to detect human falls, we used a three-axis accelerator and a three-axis gyroscope in a mobile phone. We used the Fourier descriptor-based frequency analysis method to classify both normal and falling status. From the experimental results, the proposed method detects falling status with 96.14% accuracy.

  6. TAO-2/SPARTE, a language-enhanced computer aided teleoperation system

    International Nuclear Information System (INIS)

    Gravez, P.; Fournier, R.

    1991-01-01

    TAO-2 is a computer system designed by CEA/DTA/UR for the remote control of nuclear servicing servomanipulators. It results from several years of research which have led to the current availability of an industrial product featuring highly advanced performances. For undersea applications, a development has also been carried out with CYBERNETIX for controlling the new hydraulic arm built by this company. An integral element of TAO-2 is the SPARTE language which deals with off-line task programming and focuses on combined manual, automatic and mixed control modes. Additionally, it takes into account the on-line part of the human operator relative to adjustment, monitoring and incident recovery. Other promising features are hybrid control specification, mechanisms for the management of external events and 'learning by touching' capabilities. The present paper describes the basic principles of TAO-2. It first recalls the fundamentals of Computer Aided Teleoperation (CAT). The functional and hardware architectures which implement the TAO-2 CAT concepts are then outlined. The next parts emphasize the original characteristics of the SPARTE control and programming language. The paper ends with a brief presentation of our approach for CAT symbolic control

  7. Clinical evaluation of a computer-aided diagnosis system for determining cancer aggressiveness in prostate MRI

    International Nuclear Information System (INIS)

    Litjens, Geert J.S.; Barentsz, Jelle O.; Karssemeijer, Nico; Huisman, Henkjan J.

    2015-01-01

    To investigate the added value of computer-aided diagnosis (CAD) on the diagnostic accuracy of PIRADS reporting and the assessment of cancer aggressiveness. Multi-parametric MRI and histopathological outcome of MR-guided biopsies of a consecutive set of 130 patients were included. All cases were prospectively PIRADS reported and the reported lesions underwent CAD analysis. Logistic regression combined the CAD prediction and radiologist PIRADS score into a combination score. Receiver-operating characteristic (ROC) analysis and Spearman's correlation coefficient were used to assess the diagnostic accuracy and correlation to cancer grade. Evaluation was performed for discriminating benign lesions from cancer and for discriminating indolent from aggressive lesions. In total 141 lesions (107 patients) were included for final analysis. The area-under-the-ROC-curve of the combination score was higher than for the PIRADS score of the radiologist (benign vs. cancer, 0.88 vs. 0.81, p = 0.013 and indolent vs. aggressive, 0.88 vs. 0.78, p < 0.01). The combination score correlated significantly stronger with cancer grade (0.69, p = 0.0014) than the individual CAD system or radiologist (0.54 and 0.58). Combining CAD prediction and PIRADS into a combination score has the potential to improve diagnostic accuracy. Furthermore, such a combination score has a strong correlation with cancer grade. (orig.)

  8. A general-purpose development environment for intelligent computer-aided training systems

    Science.gov (United States)

    Savely, Robert T.

    1990-01-01

    Space station training will be a major task, requiring the creation of large numbers of simulation-based training systems for crew, flight controllers, and ground-based support personnel. Given the long duration of space station missions and the large number of activities supported by the space station, the extension of space shuttle training methods to space station training may prove to be impractical. The application of artificial intelligence technology to simulation training can provide the ability to deliver individualized training to large numbers of personnel in a distributed workstation environment. The principal objective of this project is the creation of a software development environment which can be used to build intelligent training systems for procedural tasks associated with the operation of the space station. Current NASA Johnson Space Center projects and joint projects with other NASA operational centers will result in specific training systems for existing space shuttle crew, ground support personnel, and flight controller tasks. Concurrently with the creation of these systems, a general-purpose development environment for intelligent computer-aided training systems will be built. Such an environment would permit the rapid production, delivery, and evolution of training systems for space station crew, flight controllers, and other support personnel. The widespread use of such systems will serve to preserve task and training expertise, support the training of many personnel in a distributed manner, and ensure the uniformity and verifiability of training experiences. As a result, significant reductions in training costs can be realized while safety and the probability of mission success can be enhanced.

  9. Computer-Aided System Engineering and Analysis (CASE/A) Programmer's Manual, Version 5.0

    Science.gov (United States)

    Knox, J. C.

    1996-01-01

    The Computer Aided System Engineering and Analysis (CASE/A) Version 5.0 Programmer's Manual provides the programmer and user with information regarding the internal structure of the CASE/A 5.0 software system. CASE/A 5.0 is a trade study tool that provides modeling/simulation capabilities for analyzing environmental control and life support systems and active thermal control systems. CASE/A has been successfully used in studies such as the evaluation of carbon dioxide removal in the space station. CASE/A modeling provides a graphical and command-driven interface for the user. This interface allows the user to construct a model by placing equipment components in a graphical layout of the system hardware, then connect the components via flow streams and define their operating parameters. Once the equipment is placed, the simulation time and other control parameters can be set to run the simulation based on the model constructed. After completion of the simulation, graphical plots or text files can be obtained for evaluation of the simulation results over time. Additionally, users have the capability to control the simulation and extract information at various times in the simulation (e.g., control equipment operating parameters over the simulation time or extract plot data) by using "User Operations (OPS) Code." This OPS code is written in FORTRAN with a canned set of utility subroutines for performing common tasks. CASE/A version 5.0 software runs under the VAX VMS(Trademark) environment. It utilizes the Tektronics 4014(Trademark) graphics display system and the VTIOO(Trademark) text manipulation/display system.

  10. DESIGN AND DEVELOP A COMPUTER AIDED DESIGN FOR AUTOMATIC EXUDATES DETECTION FOR DIABETIC RETINOPATHY SCREENING

    Directory of Open Access Journals (Sweden)

    C. A. SATHIYAMOORTHY

    2016-04-01

    Full Text Available Diabetic Retinopathy is a severe and widely spread eye disease which can lead to blindness. One of the main symptoms for vision loss is Exudates and it could be prevented by applying an early screening process. In the Existing systems, a Fuzzy C-Means Clustering technique is used for detecting the exudates for analyzation. The main objective of this paper is, to improve the efficiency of the Exudates detection in diabetic retinopathy images. To do this, a three Stage – [TS] approach is introduced for detecting and extracting the exudates automatically from the retinal images for screening the Diabetic retinopathy. TS functions on the image in three levels such as Pre-processing the image, enhancing the image and detecting the Exudates accurately. After successful detection, the detected exudates are classified using GLCM method for finding the accuracy. The TS approach is experimented using MATLAB software and the performance evaluation can be proved by comparing the results with the existing approach’s result and with the hand-drawn ground truths images from the expert ophthalmologist.

  11. Computer-Aided Diagnosis Based on Convolutional Neural Network System for Colorectal Polyp Classification: Preliminary Experience.

    Science.gov (United States)

    Komeda, Yoriaki; Handa, Hisashi; Watanabe, Tomohiro; Nomura, Takanobu; Kitahashi, Misaki; Sakurai, Toshiharu; Okamoto, Ayana; Minami, Tomohiro; Kono, Masashi; Arizumi, Tadaaki; Takenaka, Mamoru; Hagiwara, Satoru; Matsui, Shigenaga; Nishida, Naoshi; Kashida, Hiroshi; Kudo, Masatoshi

    2017-01-01

    Computer-aided diagnosis (CAD) is becoming a next-generation tool for the diagnosis of human disease. CAD for colon polyps has been suggested as a particularly useful tool for trainee colonoscopists, as the use of a CAD system avoids the complications associated with endoscopic resections. In addition to conventional CAD, a convolutional neural network (CNN) system utilizing artificial intelligence (AI) has been developing rapidly over the past 5 years. We attempted to generate a unique CNN-CAD system with an AI function that studied endoscopic images extracted from movies obtained with colonoscopes used in routine examinations. Here, we report our preliminary results of this novel CNN-CAD system for the diagnosis of colon polyps. A total of 1,200 images from cases of colonoscopy performed between January 2010 and December 2016 at Kindai University Hospital were used. These images were extracted from the video of actual endoscopic examinations. Additional video images from 10 cases of unlearned processes were retrospectively assessed in a pilot study. They were simply diagnosed as either an adenomatous or nonadenomatous polyp. The number of images used by AI to learn to distinguish adenomatous from nonadenomatous was 1,200:600. These images were extracted from the videos of actual endoscopic examinations. The size of each image was adjusted to 256 × 256 pixels. A 10-hold cross-validation was carried out. The accuracy of the 10-hold cross-validation is 0.751, where the accuracy is the ratio of the number of correct answers over the number of all the answers produced by the CNN. The decisions by the CNN were correct in 7 of 10 cases. A CNN-CAD system using routine colonoscopy might be useful for the rapid diagnosis of colorectal polyp classification. Further prospective studies in an in vivo setting are required to confirm the effectiveness of a CNN-CAD system in routine colonoscopy. © 2017 S. Karger AG, Basel.

  12. A Computer-Aided Diagnosis System for Breast Cancer Combining Mammography and Proteomics

    Science.gov (United States)

    2007-05-01

    for sonography,” Ultrasound Med. Biol. 26, 405-411 2000. 20K. Horsch, M. L. Giger, L. A. Venta , and C. J. Vyborny, “Computerized diagnosis of breast...lesions on ultrasound,” Med. Phys. 29, 157-164 2002. 21K. Horsch, M. L. Giger, C. J. Vyborny, and L. A. Venta , “Performance of computer-aided...Horsch K, Giger ML, Vyborny CJ, Venta LA. Performance of computer-aided diagnosis in the interpretation of lesions on breast sonography. Acad Radiol

  13. Decision optimization of case-based computer-aided decision systems using genetic algorithms with application to mammography

    International Nuclear Information System (INIS)

    Mazurowski, Maciej A; Habas, Piotr A; Zurada, Jacek M; Tourassi, Georgia D

    2008-01-01

    This paper presents an optimization framework for improving case-based computer-aided decision (CB-CAD) systems. The underlying hypothesis of the study is that each example in the knowledge database of a medical decision support system has different importance in the decision making process. A new decision algorithm incorporating an importance weight for each example is proposed to account for these differences. The search for the best set of importance weights is defined as an optimization problem and a genetic algorithm is employed to solve it. The optimization process is tailored to maximize the system's performance according to clinically relevant evaluation criteria. The study was performed using a CAD system developed for the classification of regions of interests (ROIs) in mammograms as depicting masses or normal tissue. The system was constructed and evaluated using a dataset of ROIs extracted from the Digital Database for Screening Mammography (DDSM). Experimental results show that, according to receiver operator characteristic (ROC) analysis, the proposed method significantly improves the overall performance of the CAD system as well as its average specificity for high breast mass detection rates

  14. Is computer aided detection (CAD) cost effective in screening mammography? A model based on the CADET II study

    Science.gov (United States)

    2011-01-01

    Background Single reading with computer aided detection (CAD) is an alternative to double reading for detecting cancer in screening mammograms. The aim of this study is to investigate whether the use of a single reader with CAD is more cost-effective than double reading. Methods Based on data from the CADET II study, the cost-effectiveness of single reading with CAD versus double reading was measured in terms of cost per cancer detected. Cost (Pound (£), year 2007/08) of single reading with CAD versus double reading was estimated assuming a health and social service perspective and a 7 year time horizon. As the equipment cost varies according to the unit size a separate analysis was conducted for high, average and low volume screening units. One-way sensitivity analyses were performed by varying the reading time, equipment and assessment cost, recall rate and reader qualification. Results CAD is cost increasing for all sizes of screening unit. The introduction of CAD is cost-increasing compared to double reading because the cost of CAD equipment, staff training and the higher assessment cost associated with CAD are greater than the saving in reading costs. The introduction of single reading with CAD, in place of double reading, would produce an additional cost of £227 and £253 per 1,000 women screened in high and average volume units respectively. In low volume screening units, the high cost of purchasing the equipment will results in an additional cost of £590 per 1,000 women screened. One-way sensitivity analysis showed that the factors having the greatest effect on the cost-effectiveness of CAD with single reading compared with double reading were the reading time and the reader's professional qualification (radiologist versus advanced practitioner). Conclusions Without improvements in CAD effectiveness (e.g. a decrease in the recall rate) CAD is unlikely to be a cost effective alternative to double reading for mammography screening in UK. This study

  15. CASTLE3D - A Computer Aided System for Labelling Archaeological Excavations in 3D

    Science.gov (United States)

    Houshiar, H.; Borrmann, D.; Elseberg, J.; Nüchter, A.; Näth, F.; Winkler, S.

    2015-08-01

    Documentation of archaeological excavation sites with conventional methods and tools such as hand drawings, measuring tape and archaeological notes is time consuming. This process is prone to human errors and the quality of the documentation depends on the qualification of the archaeologist on site. Use of modern technology and methods in 3D surveying and 3D robotics facilitate and improve this process. Computer-aided systems and databases improve the documentation quality and increase the speed of data acquisition. 3D laser scanning is the state of the art in modelling archaeological excavation sites, historical sites and even entire cities or landscapes. Modern laser scanners are capable of data acquisition of up to 1 million points per second. This provides a very detailed 3D point cloud of the environment. 3D point clouds and 3D models of an excavation site provide a better representation of the environment for the archaeologist and for documentation. The point cloud can be used both for further studies on the excavation and for the presentation of results. This paper introduces a Computer aided system for labelling archaeological excavations in 3D (CASTLE3D). Consisting of a set of tools for recording and georeferencing the 3D data from an excavation site, CASTLE3D is a novel documentation approach in industrial archaeology. It provides a 2D and 3D visualisation of the data and an easy-to-use interface that enables the archaeologist to select regions of interest and to interact with the data in both representations. The 2D visualisation and a 3D orthogonal view of the data provide cuts of the environment that resemble the traditional hand drawings. The 3D perspective view gives a realistic view of the environment. CASTLE3D is designed as an easy-to-use on-site semantic mapping tool for archaeologists. Each project contains a predefined set of semantic information that can be used to label findings in the data. Multiple regions of interest can be joined under

  16. Computer-Aided Detection with a Portable Electrocardiographic Recorder and Acceleration Sensors for Monitoring Obstructive Sleep Apnea

    Directory of Open Access Journals (Sweden)

    Ji-Won Baek

    2014-03-01

    Full Text Available Obstructive sleep apnea syndrome is a sleep-related breathing disorder that is caused by obstruction of the upper airway. This condition may be related with many clinical sequelae such as cardiovascular disease, high blood pressure, stroke, diabetes, and clinical depression. To diagnosis obstructive sleep apnea, in-laboratory full polysomnography is considered as a standard test to determine the severity of respiratory disturbance. However, polysomnography is expensive and complicated to perform. In this research, we explore a computer-aided diagnosis system with portable ECG equipment and tri-accelerometer (x, y, and z-axes that can automatically analyze biosignals and test for OSA. Traditional approaches to sleep apnea data analysis have been criticized; however, there are not enough suggestions to resolve the existing problems. As an effort to resolve this issue, we developed an approach to record ECG signals and abdominal movements induced by breathing by affixing ECG-enabled electrodes onto a triaxial accelerometer. With the two signals simultaneously measured, the apnea data obtained would be more accurate, relative to cases where a single signal is measured. This would be helpful in diagnosing OSA. Moreover, a useful feature point can be extracted from the two signals after applying a signal processing algorithm, and the extracted feature point can be applied in designing a computer-aided diagnosis algorithm using a machine learning technique.

  17. Creation of system of computer-aided design for technological objects

    Science.gov (United States)

    Zubkova, T. M.; Tokareva, M. A.; Sultanov, N. Z.

    2018-05-01

    Due to the competition in the market of process equipment, its production should be flexible, retuning to various product configurations, raw materials and productivity, depending on the current market needs. This process is not possible without CAD (computer-aided design). The formation of CAD begins with planning. Synthesizing, analyzing, evaluating, converting operations, as well as visualization and decision-making operations, can be automated. Based on formal description of the design procedures, the design route in the form of an oriented graph is constructed. The decomposition of the design process, represented by the formalized description of the design procedures, makes it possible to make an informed choice of the CAD component for the solution of the task. The object-oriented approach allows us to consider the CAD as an independent system whose properties are inherited from the components. The first step determines the range of tasks to be performed by the system, and a set of components for their implementation. The second one is the configuration of the selected components. The interaction between the selected components is carried out using the CALS standards. The chosen CAD / CAE-oriented approach allows creating a single model, which is stored in the database of the subject area. Each of the integration stages is implemented as a separate functional block. The transformation of the CAD model into the model of the internal representation is realized by the block of searching for the geometric parameters of the technological machine, in which the XML-model of the construction is obtained on the basis of the feature method from the theory of image recognition. The configuration of integrated components is divided into three consecutive steps: configuring tasks, components, interfaces. The configuration of the components is realized using the theory of "soft computations" using the Mamdani fuzzy inference algorithm.

  18. Selection of an optimal neural network architecture for computer-aided detection of microcalcifications - Comparison of automated optimization techniques

    International Nuclear Information System (INIS)

    Gurcan, Metin N.; Sahiner, Berkman; Chan Heangping; Hadjiiski, Lubomir; Petrick, Nicholas

    2001-01-01

    Many computer-aided diagnosis (CAD) systems use neural networks (NNs) for either detection or classification of abnormalities. Currently, most NNs are 'optimized' by manual search in a very limited parameter space. In this work, we evaluated the use of automated optimization methods for selecting an optimal convolution neural network (CNN) architecture. Three automated methods, the steepest descent (SD), the simulated annealing (SA), and the genetic algorithm (GA), were compared. We used as an example the CNN that classifies true and false microcalcifications detected on digitized mammograms by a prescreening algorithm. Four parameters of the CNN architecture were considered for optimization, the numbers of node groups and the filter kernel sizes in the first and second hidden layers, resulting in a search space of 432 possible architectures. The area A z under the receiver operating characteristic (ROC) curve was used to design a cost function. The SA experiments were conducted with four different annealing schedules. Three different parent selection methods were compared for the GA experiments. An available data set was split into two groups with approximately equal number of samples. By using the two groups alternately for training and testing, two different cost surfaces were evaluated. For the first cost surface, the SD method was trapped in a local minimum 91% (392/432) of the time. The SA using the Boltzman schedule selected the best architecture after evaluating, on average, 167 architectures. The GA achieved its best performance with linearly scaled roulette-wheel parent selection; however, it evaluated 391 different architectures, on average, to find the best one. The second cost surface contained no local minimum. For this surface, a simple SD algorithm could quickly find the global minimum, but the SA with the very fast reannealing schedule was still the most efficient. The same SA scheme, however, was trapped in a local minimum on the first cost

  19. Re-engineering software systems in the Department of Defense using integrated computer aided software engineering tools

    OpenAIRE

    Jennings, Charles A.

    1992-01-01

    Approved for public release; distribution is unlimited The Department of Defense (DoD) is plagues with severe cost overruns and delays in developing software systems. Existing software within Dod, some developed 15-to 20 years ago, require continual maintenance and modification. Major difficulties arise with maintaining older systems due to cryptic source code and a lack of adequate documentation. To remedy this situation, the DoD, is pursuing the integrated computer aided software engi...

  20. Implementation of combined SVM-algorithm and computer-aided perception feedback for pulmonary nodule detection

    Science.gov (United States)

    Pietrzyk, Mariusz W.; Rannou, Didier; Brennan, Patrick C.

    2012-02-01

    This pilot study examines the effect of a novel decision support system in medical image interpretation. This system is based on combining image spatial frequency properties and eye-tracking data in order to recognize over and under calling errors. Thus, before it can be implemented as a detection aided schema, training is required during which SVMbased algorithm learns to recognize FP from all reported outcomes, and, FN from all unreported prolonged dwelled regions. Eight radiologists inspected 50 PA chest radiographs with the specific task of identifying lung nodules. Twentyfive cases contained CT proven subtle malignant lesions (5-20mm), but prevalence was not known by the subjects, who took part in two sequential reading sessions, the second, without and with support system feedback. MCMR ROC DBM and JAFROC analyses were conducted and demonstrated significantly higher scores following feedback with p values of 0.04, and 0.03 respectively, highlighting significant improvements in radiology performance once feedback was used. This positive effect on radiologists' performance might have important implications for future CAD-system development.

  1. Large scale deep learning for computer aided detection of mammographic lesions.

    Science.gov (United States)

    Kooi, Thijs; Litjens, Geert; van Ginneken, Bram; Gubern-Mérida, Albert; Sánchez, Clara I; Mann, Ritse; den Heeten, Ard; Karssemeijer, Nico

    2017-01-01

    Recent advances in machine learning yielded new techniques to train deep neural networks, which resulted in highly successful applications in many pattern recognition tasks such as object detection and speech recognition. In this paper we provide a head-to-head comparison between a state-of-the art in mammography CAD system, relying on a manually designed feature set and a Convolutional Neural Network (CNN), aiming for a system that can ultimately read mammograms independently. Both systems are trained on a large data set of around 45,000 images and results show the CNN outperforms the traditional CAD system at low sensitivity and performs comparable at high sensitivity. We subsequently investigate to what extent features such as location and patient information and commonly used manual features can still complement the network and see improvements at high specificity over the CNN especially with location and context features, which contain information not available to the CNN. Additionally, a reader study was performed, where the network was compared to certified screening radiologists on a patch level and we found no significant difference between the network and the readers. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. A computer - aided system for the the E.D.F. 1400 MW. Nuclear power plants control

    International Nuclear Information System (INIS)

    Beltranda, G.; Philipps, C.

    1988-01-01

    The future E.D.F. 1400 MW nuclear power plants (due to be commissioned in 1991 at CHOOZ) are provided with a control and instrumentation system including the following levels: - sensors and actuators (LEVEL 0): this is the interface of the elementary acquisition and control signals; - the programmable logical and numerical controllers (LEVEL 1) for the logical control sequences and analog adjustment sequences for the whole equipment of the facilities; - the control room (LEVEL 2) including the computer-aided operation system as well as the wall mimic diagram and the auxiliary panel directly connected to the controllers. This is the processing and control conversational level; - the maintenance and site computer-aided systems (LEVEL 3). This paper aims at describing the computer-aided operation system (called KIC N4), its main functions, its architecture and the solutions retained as regards its softwares and the high-quality of data required. The achievement of this system has been entrusted by EDF to the SEMA. METRA/CIMSA-SINTRA grouping, among which SEMA.METRA is the leading company

  3. Multiparametric magnetic resonance imaging of the prostate with computer-aided detection: experienced observer performance study

    International Nuclear Information System (INIS)

    Giannini, Valentina; Mazzetti, Simone; Armando, Enrico; Carabalona, Silvia; Russo, Filippo; Giacobbe, Alessandro; Muto, Giovanni; Regge, Daniele

    2017-01-01

    To compare the performance of experienced readers in detecting prostate cancer (PCa) using likelihood maps generated by a CAD system with that of unassisted interpretation of multiparametric magnetic resonance imaging (mp-MRI). Three experienced radiologists reviewed mp-MRI prostate cases twice. First, readers observed CAD marks on a likelihood map and classified as positive those suspicious for cancer. After 6 weeks, radiologists interpreted mp-MRI examinations unassisted, using their favourite protocol. Sensitivity, specificity, reading time and interobserver variability were compared for the two reading paradigms. The dataset comprised 89 subjects of whom 35 with at least one significant PCa. Sensitivity was 80.9% (95% CI 72.1-88.0%) and 87.6% (95% CI 79.8-93.2; p = 0.105) for unassisted and CAD paradigm respectively. Sensitivity was higher with CAD for lesions with GS > 6 (91.3% vs 81.2%; p = 0.046) or diameter ≥10 mm (95.0% vs 80.0%; p = 0.006). Specificity was not affected by CAD. The average reading time with CAD was significantly lower (220 s vs 60 s; p < 0.001). Experienced readers using likelihood maps generated by a CAD scheme can detect more patients with ≥10 mm PCa lesions than unassisted MRI interpretation; overall reporting time is shorter. To gain more insight into CAD-human interaction, different reading paradigms should be investigated. (orig.)

  4. Multiparametric magnetic resonance imaging of the prostate with computer-aided detection: experienced observer performance study

    Energy Technology Data Exchange (ETDEWEB)

    Giannini, Valentina; Mazzetti, Simone; Armando, Enrico; Carabalona, Silvia; Russo, Filippo [FPO, IRCCS, Department of Radiology at the Candiolo Cancer Institute, Candiolo, Turin (Italy); Giacobbe, Alessandro [San Giovanni Bosco Hospital, Department of Urology, Turin (Italy); Muto, Giovanni [University Campus Biomedico, Department of Urology, Rome (Italy); Regge, Daniele [FPO, IRCCS, Department of Radiology at the Candiolo Cancer Institute, Candiolo, Turin (Italy); University of Torino, A.O.U. Citta della Salute e della Scienza, Department of Surgical Sciences, Turin (Italy)

    2017-10-15

    To compare the performance of experienced readers in detecting prostate cancer (PCa) using likelihood maps generated by a CAD system with that of unassisted interpretation of multiparametric magnetic resonance imaging (mp-MRI). Three experienced radiologists reviewed mp-MRI prostate cases twice. First, readers observed CAD marks on a likelihood map and classified as positive those suspicious for cancer. After 6 weeks, radiologists interpreted mp-MRI examinations unassisted, using their favourite protocol. Sensitivity, specificity, reading time and interobserver variability were compared for the two reading paradigms. The dataset comprised 89 subjects of whom 35 with at least one significant PCa. Sensitivity was 80.9% (95% CI 72.1-88.0%) and 87.6% (95% CI 79.8-93.2; p = 0.105) for unassisted and CAD paradigm respectively. Sensitivity was higher with CAD for lesions with GS > 6 (91.3% vs 81.2%; p = 0.046) or diameter ≥10 mm (95.0% vs 80.0%; p = 0.006). Specificity was not affected by CAD. The average reading time with CAD was significantly lower (220 s vs 60 s; p < 0.001). Experienced readers using likelihood maps generated by a CAD scheme can detect more patients with ≥10 mm PCa lesions than unassisted MRI interpretation; overall reporting time is shorter. To gain more insight into CAD-human interaction, different reading paradigms should be investigated. (orig.)

  5. SINCRO/CAR: An interactive numerical system for computer-aided control engineering and maintenance

    International Nuclear Information System (INIS)

    Zwingelstein, G.; Despujols, A.

    1986-01-01

    This presentation describes a dialogue-oriented software implemented on a portable computer for computer-aided engineering and training in control instrumentation and also for on-line verification of the performances of the analog controllers installed on power plants. The SINCRO/CAR software includes algorithms for controller design, simulation, identification, optimization, frequency response and real time data acquisition. Various results obtained on fossil-fired and nuclear plants are given to illustrate the efficiency of the SINCRO/CAR software

  6. Demonstration Project on Mammographic Computer-Aided Diagnosis for Breast Cancer Detection

    National Research Council Canada - National Science Library

    Doi, Kunio

    2000-01-01

    ...) in mammographic detection of breast cancer. Our plan is to develop advanced CAD schemes for detection and characterization of clustered microcalcifications and masses by incorporating artificial neural networks and various image processing techniques...

  7. Demonstration Project on Mammographic Computer-Aided Diagnosis for Breast Cancer Detection

    National Research Council Canada - National Science Library

    Doi, Kunio

    2001-01-01

    ...) in mammographic detection of breast cancer. Our plan is to develop advanced CAD schemes for detection and characterization of clustered microcalcifications and masses by incorporating artificial neural networks and various image processing techniques...

  8. Demonstration Project on Mammographic Computer-Aided Diagnosis for Breast Cancer Detection

    National Research Council Canada - National Science Library

    Doi, Kunio

    1999-01-01

    ...) in mammographic detection of breast cancer. Our plan is to develop advanced CAD schemes for detection and characterization of clustered microcalcifications and masses by incorporating artificial neural networks and various image processing techniques...

  9. Demonstration Project on Mammographic Computer-Aided Diagnosis for Breast Cancer Detection

    National Research Council Canada - National Science Library

    Doi, Kunio

    2002-01-01

    ...) in mammographic detection of breast cancer. Our plan is to develop advanced CAD schemes for detection and characterization of clustered microcalcifications and masses by incorporating artificial neural networks and various image processing techniques...

  10. Pulmonary nodules: effect of adaptive statistical iterative reconstruction (ASIR) technique on performance of a computer-aided detection (CAD) system-comparison of performance between different-dose CT scans.

    Science.gov (United States)

    Yanagawa, Masahiro; Honda, Osamu; Kikuyama, Ayano; Gyobu, Tomoko; Sumikawa, Hiromitsu; Koyama, Mitsuhiro; Tomiyama, Noriyuki

    2012-10-01

    To evaluate the effects of ASIR on CAD system of pulmonary nodules using clinical routine-dose CT and lower-dose CT. Thirty-five patients (body mass index, 22.17 ± 4.37 kg/m(2)) were scanned by multidetector-row CT with tube currents (clinical routine-dose CT, automatically adjusted mA; lower-dose CT, 10 mA) and X-ray voltage (120 kVp). Each 0.625-mm-thick image was reconstructed at 0%-, 50%-, and 100%-ASIR: 0%-ASIR is reconstructed using only the filtered back-projection algorithm (FBP), while 100%-ASIR is reconstructed using the maximum ASIR and 50%-ASIR implies a blending of 50% FBP and ASIR. CAD output was compared retrospectively with the results of the reference standard which was established using a consensus panel of three radiologists. Data were analyzed using Bonferroni/Dunn's method. Radiation dose was calculated by multiplying dose-length product by conversion coefficient of 0.021. The consensus panel found 265 non-calcified nodules ≤ 30 mm (ground-glass opacity [GGO], 103; part-solid, 34; and solid, 128). CAD sensitivity was significantly higher at 100%-ASIR [clinical routine-dose CT, 71% (overall), 49% (GGO); lower-dose CT, 52% (overall), 67% (solid)] than at 0%-ASIR [clinical routine-dose CT, 54% (overall), 25% (GGO); lower-dose CT, 36% (overall), 50% (solid)] (pASIR (clinical routine-dose CT, 8.5; lower-dose CT, 6.2) than at 0%-ASIR (clinical routine-dose CT, 4.6; lower-dose CT, 3.5; pASIR on lower-dose CT is almost equal to that at 0%-ASIR on clinical routine-dose CT. ASIR can increase CAD sensitivity despite increased false-positive findings. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  11. Computer-aided detection of pulmonary embolism at CT pulmonary angiography: can it improve performance of inexperienced readers?

    International Nuclear Information System (INIS)

    Blackmon, Kevin N.; McCain, Joshua W.; Koonce, James D.; Costello, Philip; Florin, Charles; Bogoni, Luca; Salganicoff, Marcos; Lee, Heon; Bastarrika, Gorka; Thilo, Christian; Joseph Schoepf, U.

    2011-01-01

    To evaluate the effect of a computer-aided detection (CAD) algorithm on the performance of novice readers for detection of pulmonary embolism (PE) at CT pulmonary angiography (CTPA). We included CTPA examinations of 79 patients (50 female, 52 ± 18 years). Studies were evaluated by two independent inexperienced readers who marked all vessels containing PE. After 3 months all studies were reevaluated by the same two readers, this time aided by CAD prototype. A consensus read by three expert radiologists served as the reference standard. Statistical analysis used χ 2 and McNemar testing. Expert consensus revealed 119 PEs in 32 studies. For PE detection, the sensitivity of CAD alone was 78%. Inexperienced readers' initial interpretations had an average per-PE sensitivity of 50%, which improved to 71% (p < 0.001) with CAD as a second reader. False positives increased from 0.18 to 0.25 per study (p = 0.03). Per-study, the readers initially detected 27/32 positive studies (84%); with CAD this number increased to 29.5 studies (92%; p = 0.125). Our results suggest that CAD significantly improves the sensitivity of PE detection for inexperienced readers with a small but appreciable increase in the rate of false positives. (orig.)

  12. Computer-aided detection of pulmonary embolism at CT pulmonary angiography: can it improve performance of inexperienced readers?

    Energy Technology Data Exchange (ETDEWEB)

    Blackmon, Kevin N.; McCain, Joshua W.; Koonce, James D.; Costello, Philip [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Florin, Charles; Bogoni, Luca; Salganicoff, Marcos [Siemens AG, H IM SYNGO CAD Research and Development, Malvern, PA (United States); Lee, Heon [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Seoul Medical Center, Department of Radiology, Seoul (Korea, Republic of); Bastarrika, Gorka [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Navarra, Department of Radiology, Pamplona (Spain); Thilo, Christian; Joseph Schoepf, U. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States)

    2011-06-15

    To evaluate the effect of a computer-aided detection (CAD) algorithm on the performance of novice readers for detection of pulmonary embolism (PE) at CT pulmonary angiography (CTPA). We included CTPA examinations of 79 patients (50 female, 52 {+-} 18 years). Studies were evaluated by two independent inexperienced readers who marked all vessels containing PE. After 3 months all studies were reevaluated by the same two readers, this time aided by CAD prototype. A consensus read by three expert radiologists served as the reference standard. Statistical analysis used {chi}{sup 2} and McNemar testing. Expert consensus revealed 119 PEs in 32 studies. For PE detection, the sensitivity of CAD alone was 78%. Inexperienced readers' initial interpretations had an average per-PE sensitivity of 50%, which improved to 71% (p < 0.001) with CAD as a second reader. False positives increased from 0.18 to 0.25 per study (p = 0.03). Per-study, the readers initially detected 27/32 positive studies (84%); with CAD this number increased to 29.5 studies (92%; p = 0.125). Our results suggest that CAD significantly improves the sensitivity of PE detection for inexperienced readers with a small but appreciable increase in the rate of false positives. (orig.)

  13. A novel computer-aided diagnosis system for breast MRI based on feature selection and ensemble learning.

    Science.gov (United States)

    Lu, Wei; Li, Zhe; Chu, Jinghui

    2017-04-01

    Breast cancer is a common cancer among women. With the development of modern medical science and information technology, medical imaging techniques have an increasingly important role in the early detection and diagnosis of breast cancer. In this paper, we propose an automated computer-aided diagnosis (CADx) framework for magnetic resonance imaging (MRI). The scheme consists of an ensemble of several machine learning-based techniques, including ensemble under-sampling (EUS) for imbalanced data processing, the Relief algorithm for feature selection, the subspace method for providing data diversity, and Adaboost for improving the performance of base classifiers. We extracted morphological, various texture, and Gabor features. To clarify the feature subsets' physical meaning, subspaces are built by combining morphological features with each kind of texture or Gabor feature. We tested our proposal using a manually segmented Region of Interest (ROI) data set, which contains 438 images of malignant tumors and 1898 images of normal tissues or benign tumors. Our proposal achieves an area under the ROC curve (AUC) value of 0.9617, which outperforms most other state-of-the-art breast MRI CADx systems. Compared with other methods, our proposal significantly reduces the false-positive classification rate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Computer aided detection of suspicious regions on digital mammograms : rapid segmentation and feature extraction

    Energy Technology Data Exchange (ETDEWEB)

    Ruggiero, C; Giacomini, M; Sacile, R [DIST - Department of Communication Computer and System Sciences, University of Genova, Via Opera Pia 13, 16145 Genova (Italy); Rosselli Del Turco, M [Centro per lo studio e la prevenzione oncologica, Firenze (Italy)

    1999-12-31

    A method is presented for rapid detection of suspicious regions which consists of two steps. The first step is segmentation based on texture analysis consisting of : histogram equalization, Laws filtering for texture analysis, Gaussian blur and median filtering to enhance differences between tissues in different respects, histogram thresholding to obtain a binary image, logical masking in order to detect regions to be discarded from the analysis, edge detection. This method has been tested on 60 images, obtaining 93% successful detection of suspicious regions. (authors) 4 refs, 9 figs, 1 tabs.

  15. [Accuracy of computer aided measurement for detecting dental proximal caries lesions in images of cone-beam computed tomography].

    Science.gov (United States)

    Zhang, Z L; Li, J P; Li, G; Ma, X C

    2017-02-09

    Objective: To establish and validate a computer program used to aid the detection of dental proximal caries in the images cone beam computed tomography (CBCT) images. Methods: According to the characteristics of caries lesions in X-ray images, a computer aided detection program for proximal caries was established with Matlab and Visual C++. The whole process for caries lesion detection included image import and preprocessing, measuring average gray value of air area, choosing region of interest and calculating gray value, defining the caries areas. The program was used to examine 90 proximal surfaces from 45 extracted human teeth collected from Peking University School and Hospital of Stomatology. The teeth were then scanned with a CBCT scanner (Promax 3D). The proximal surfaces of the teeth were respectively detected by caries detection program and scored by human observer for the extent of lesions with 6-level-scale. With histologic examination serving as the reference standard, the caries detection program and the human observer performances were assessed with receiver operating characteristic (ROC) curves. Student t -test was used to analyze the areas under the ROC curves (AUC) for the differences between caries detection program and human observer. Spearman correlation coefficient was used to analyze the detection accuracy of caries depth. Results: For the diagnosis of proximal caries in CBCT images, the AUC values of human observers and caries detection program were 0.632 and 0.703, respectively. There was a statistically significant difference between the AUC values ( P= 0.023). The correlation between program performance and gold standard (correlation coefficient r (s)=0.525) was higher than that of observer performance and gold standard ( r (s)=0.457) and there was a statistically significant difference between the correlation coefficients ( P= 0.000). Conclusions: The program that automatically detects dental proximal caries lesions could improve the

  16. Computer aided drug design

    Science.gov (United States)

    Jain, A.

    2017-08-01

    Computer based method can help in discovery of leads and can potentially eliminate chemical synthesis and screening of many irrelevant compounds, and in this way, it save time as well as cost. Molecular modeling systems are powerful tools for building, visualizing, analyzing and storing models of complex molecular structure that can help to interpretate structure activity relationship. The use of various techniques of molecular mechanics and dynamics and software in Computer aided drug design along with statistics analysis is powerful tool for the medicinal chemistry to synthesis therapeutic and effective drugs with minimum side effect.

  17. Digital breast tomosynthesis: computer-aided detection of clustered microcalcifications on planar projection images

    International Nuclear Information System (INIS)

    Samala, Ravi K; Chan, Heang-Ping; Lu, Yao; Hadjiiski, Lubomir M; Wei, Jun; Helvie, Mark A

    2014-01-01

    This paper describes a new approach to detect microcalcification clusters (MCs) in digital breast tomosynthesis (DBT) via its planar projection (PPJ) image. With IRB approval, two-view (cranio-caudal and mediolateral oblique views) DBTs of human subject breasts were obtained with a GE GEN2 prototype DBT system that acquires 21 projection angles spanning 60° in 3° increments. A data set of 307 volumes (154 human subjects) was divided by case into independent training (127 with MCs) and test sets (104 with MCs and 76 free of MCs). A simultaneous algebraic reconstruction technique with multiscale bilateral filtering (MSBF) regularization was used to enhance microcalcifications and suppress noise. During the MSBF regularized reconstruction, the DBT volume was separated into high frequency (HF) and low frequency components representing microcalcifications and larger structures. At the final iteration, maximum intensity projection was applied to the regularized HF volume to generate a PPJ image that contained MCs with increased contrast-to-noise ratio (CNR) and reduced search space. High CNR objects in the PPJ image were extracted and labeled as microcalcification candidates. Convolution neural network trained to recognize the image pattern of microcalcifications was used to classify the candidates into true calcifications and tissue structures and artifacts. The remaining microcalcification candidates were grouped into MCs by dynamic conditional clustering based on adaptive CNR threshold and radial distance criteria. False positive (FP) clusters were further reduced using the number of candidates in a cluster, CNR and size of microcalcification candidates. At 85% sensitivity an FP rate of 0.71 and 0.54 was achieved for view- and case-based sensitivity, respectively, compared to 2.16 and 0.85 achieved in DBT. The improvement was significant (p-value = 0.003) by JAFROC analysis. (paper)

  18. Can breast MRI computer-aided detection (CAD) improve radiologist accuracy for lesions detected at MRI screening and recommended for biopsy in a high-risk population?

    International Nuclear Information System (INIS)

    Arazi-Kleinman, T.; Causer, P.A.; Jong, R.A.; Hill, K.; Warner, E.

    2009-01-01

    Aim: To evaluate the sensitivity and specificity of magnetic resonance imaging (MRI) computer-aided detection (CAD) for breast MRI screen-detected lesions recommended for biopsy in a high-risk population. Material and methods: Fifty-six consecutive Breast Imaging Reporting and Data System (BI-RADS) 3-5 lesions with histopathological correlation [nine invasive cancers, 13 ductal carcinoma in situ (DCIS) and 34 benign] were retrospectively evaluated using a breast MRI CAD prototype (CAD-Gaea). CAD evaluation was performed separately and in consensus by two radiologists specializing in breast imaging, blinded to the histopathology. Thresholds of 50, 80, and 100% and delayed enhancement were independently assessed with CAD. Lesions were rated as malignant or benign according to threshold and delayed enhancement only and in combination. Sensitivities, specificities, and negative predictive values (NPV) were determined for CAD assessments versus pathology. Initial MRI BI-RADS interpretation without CAD versus CAD assessments were compared using paired binary diagnostic tests. Results: Threshold levels for lesion enhancement were: 50% to include all malignant (and all benign) lesions; and 100% for all invasive cancer and high-grade DCIS. Combined use of threshold and enhancement patterns for CAD assessment was best (73% sensitivity, 56% specificity and 76% NPV for all cancer). Sensitivities and NPV were better for invasive cancer (100%/100%) than for all malignancies (54%/76%). Radiologists' MRI interpretation was more sensitive than CAD (p = 0.05), but less specific (p = 0.001) for cancer detection. Conclusion: The breast MRI CAD system used could not improve the radiologists' accuracy for distinguishing all malignant from benign lesions, due to the poor sensitivity for DCIS detection.

  19. Progress of computer-aided detection/diagnosis (CAD in dentistryCAD in dentistry

    Directory of Open Access Journals (Sweden)

    Akitoshi Katsumata

    2014-08-01

    CAD is also useful in the detection and evaluation of dental and maxillofacial lesions. Identifying alveolar bone resorption due to periodontitis and radiolucent jaw lesions (such as radicular and dentigerous cysts are important goals for CAD. CAD can be applied not only to panoramic radiography but also to dental cone-beam computed tomography (CBCT images. Linking of CAD and teleradiology will be an important issue.

  20. Effect of Computer-Aided Detection on Mammographic Performance: Experimental Study on Readers with Different Levels of Experience

    International Nuclear Information System (INIS)

    Hukkinen, K.; Vehmas, T.; Pamilo, M.; Kivisaari, L.

    2006-01-01

    Purpose: To evaluate the effect of computer-aided detection (CAD) on the reader's performance. Material and Methods: Four screening radiologists, two novice radiologists, and two residents with no prior experience in CAD read films of 200 women without and with CAD. The films, including 16 screen-detected cancers and 35 cancers 'missed' on prior screening, were divided into two rollers: A (free time schedule) and B (prompted time schedule). Reading times were noted. Individual readings without and with CAD were compared, sensitivities and specificities were calculated. Results: The sensitivity of CAD was 70.6% and specificity 15.8%. In 408 cancer readings, the screeners found 10 and other readers 7 new cancers with the aid of CAD. The screeners changed their opinion four times and others six times from true positive to false negative when CAD was negative. CAD output produced 12 versus 13 new false-positive findings respectively after 2352 readings. CAD did not significantly affect the reader's sensitivities/specificities regardless of the time limit (P = not significant). The use of CAD increased mean time for roller reading from 56 to 63 min (P = 0.053). Conclusion: Screening radiologists benefited slightly more from CAD than other readers did, but no statistical significant difference was found in personal readings without and with CAD

  1. Computer-aided diagnosis workstation and teleradiology network system for chest diagnosis using the web medical image conference system with a new information security solution

    Science.gov (United States)

    Satoh, Hitoshi; Niki, Noboru; Eguchi, Kenji; Ohmatsu, Hironobu; Kaneko, Masahiro; Kakinuma, Ryutaro; Moriyama, Noriyuki

    2010-03-01

    Diagnostic MDCT imaging requires a considerable number of images to be read. Moreover, the doctor who diagnoses a medical image is insufficient in Japan. Because of such a background, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images, a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification and a vertebra body analysis algorithm for quantitative evaluation of osteoporosis. We also have developed the teleradiology network system by using web medical image conference system. In the teleradiology network system, the security of information network is very important subjects. Our teleradiology network system can perform Web medical image conference in the medical institutions of a remote place using the web medical image conference system. We completed the basic proof experiment of the web medical image conference system with information security solution. We can share the screen of web medical image conference system from two or more web conference terminals at the same time. An opinion can be exchanged mutually by using a camera and a microphone that are connected with the workstation that builds in some diagnostic assistance methods. Biometric face authentication used on site of teleradiology makes "Encryption of file" and "Success in login" effective. Our Privacy and information security technology of information security solution ensures compliance with Japanese regulations. As a result, patients' private information is protected. Based on these diagnostic assistance methods, we have developed a new computer-aided workstation and a new teleradiology network that can display suspected lesions three-dimensionally in a short time. The results of this study indicate that our radiological information system without film by using computer-aided diagnosis

  2. Fate of pulmonary nodules detected by computer-aided diagnosis and physician review on the computed tomography simulation images for hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Park, Hyo Jung; Kim, Jin Sung; Park, Hee Chul; Oh, Dong Ryul

    2014-01-01

    To investigate the frequency and clinical significance of detected incidental lung nodules found on computed tomography (CT) simulation images for hepatocellular carcinoma (HCC) using computer-aided diagnosis (CAD) and a physician review. Sixty-seven treatment-naive HCC patients treated with transcatheter arterial chemoembolization and radiotherapy (RT) were included for the study. Portal phase of simulation CT images was used for CAD analysis and a physician review for lung nodule detection. For automated nodule detection, a commercially available CAD system was used. To assess the performance of lung nodule detection for lung metastasis, the sensitivity, negative predictive value (NPV), and positive predictive value (PPV) were calculated. Forty-six patients had incidental nodules detected by CAD with a total of 109 nodules. Only 20 (18.3%) nodules were considered to be significant nodules by a physician review. The number of significant nodules detected by both of CAD or a physician review was 24 in 9 patients. Lung metastases developed in 11 of 46 patients who had any type of nodule. The sensitivities were 58.3% and 100% based on patient number and on the number of nodules, respectively. The NPVs were 91.4% and 100%, respectively. And the PPVs were 77.8% and 91.7%, respectively. Incidental detection of metastatic nodules was not an uncommon event. From our study, CAD could be applied to CT simulation images allowing for an increase in detection of metastatic nodules.

  3. Application of a B ampersand W developed computer aided pictorial process planning system to CQMS for manufacturing process control

    International Nuclear Information System (INIS)

    Johanson, D.C.; VandeBogart, J.E.

    1992-01-01

    Babcock ampersand Wilcox (B ampersand W) will utilize its internally developed Computer Aided Pictorial Process Planning or CAPPP (pronounced open-quotes cap cubedclose quotes) system to create a paperless manufacturing environment for the Collider Quadruple Magnets (CQM). The CAPPP system consists of networked personal computer hardware and software used to: (1) generate and maintain the documents necessary for product fabrication, (2) communicate the information contained in these documents to the production floor, and (3) obtain quality assurance and manufacturing feedback information from the production floor. The purpose of this paper is to describe the various components of the CAPPP system and explain their applicability to product fabrication, specifically quality assurance functions

  4. Computer aided detection of tumor and edema in brain FLAIR magnetic resonance image using ANN

    Science.gov (United States)

    Pradhan, Nandita; Sinha, A. K.

    2008-03-01

    This paper presents an efficient region based segmentation technique for detecting pathological tissues (Tumor & Edema) of brain using fluid attenuated inversion recovery (FLAIR) magnetic resonance (MR) images. This work segments FLAIR brain images for normal and pathological tissues based on statistical features and wavelet transform coefficients using k-means algorithm. The image is divided into small blocks of 4×4 pixels. The k-means algorithm is used to cluster the image based on the feature vectors of blocks forming different classes representing different regions in the whole image. With the knowledge of the feature vectors of different segmented regions, supervised technique is used to train Artificial Neural Network using fuzzy back propagation algorithm (FBPA). Segmentation for detecting healthy tissues and tumors has been reported by several researchers by using conventional MRI sequences like T1, T2 and PD weighted sequences. This work successfully presents segmentation of healthy and pathological tissues (both Tumors and Edema) using FLAIR images. At the end pseudo coloring of segmented and classified regions are done for better human visualization.

  5. The relationship between image resolution and computer-aided detection of breast microcalcifications and clusters

    International Nuclear Information System (INIS)

    Nunes, Fatima de Lourdes S.; Schiabel, Homero; Ferrari, Ricardo Jose; Frere, Annie France; Marques, Paulo M.Azevedo

    1996-01-01

    A technique for recognition of microcalcifications clutters in digitized mammograms based on the area-point transformation procedure is proposed. Results presented are concerned to the processing of images obtained by phantoms exposures in mammographic systems

  6. A method to test the reproducibility and to improve performance of computer-aided detection schemes for digitized mammograms

    International Nuclear Information System (INIS)

    Zheng Bin; Gur, David; Good, Walter F.; Hardesty, Lara A.

    2004-01-01

    The purpose of this study is to develop a new method for assessment of the reproducibility of computer-aided detection (CAD) schemes for digitized mammograms and to evaluate the possibility of using the implemented approach for improving CAD performance. Two thousand digitized mammograms (representing 500 cases) with 300 depicted verified masses were selected in the study. Series of images were generated for each digitized image by resampling after a series of slight image rotations. A CAD scheme developed in our laboratory was applied to all images to detect suspicious mass regions. We evaluated the reproducibility of the scheme using the detection sensitivity and false-positive rates for the original and resampled images. We also explored the possibility of improving CAD performance using three methods of combining results from the original and resampled images, including simple grouping, averaging output scores, and averaging output scores after grouping. The CAD scheme generated a detection score (from 0 to 1) for each identified suspicious region. A region with a detection score >0.5 was considered as positive. The CAD scheme detected 238 masses (79.3% case-based sensitivity) and identified 1093 false-positive regions (average 0.55 per image) in the original image dataset. In eleven repeated tests using original and ten sets of rotated and resampled images, the scheme detected a maximum of 271 masses and identified as many as 2359 false-positive regions. Two hundred and eighteen masses (80.4%) and 618 false-positive regions (26.2%) were detected in all 11 sets of images. Combining detection results improved reproducibility and the overall CAD performance. In the range of an average false-positive detection rate between 0.5 and 1 per image, the sensitivity of the scheme could be increased approximately 5% after averaging the scores of the regions detected in at least four images. At low false-positive rate (e.g., ≤average 0.3 per image), the grouping method

  7. The software developing method for multichannel computer-aided system for physical experiments control, realized by resources of national instruments LabVIEW instrumental package

    International Nuclear Information System (INIS)

    Gorskaya, E.A.; Samojlov, V.N.

    1999-01-01

    This work is describing the method of developing the computer-aided control system in integrated environment of LabVIEW. Using the object-oriented design of complex systems, the hypothetical model for methods of developing the software for computer-aided system for physical experiments control was constructed. Within the framework of that model architecture solutions and implementations of suggested method were described. (author)

  8. Applying a new computer-aided detection scheme generated imaging marker to predict short-term breast cancer risk

    Science.gov (United States)

    Mirniaharikandehei, Seyedehnafiseh; Hollingsworth, Alan B.; Patel, Bhavika; Heidari, Morteza; Liu, Hong; Zheng, Bin

    2018-05-01

    This study aims to investigate the feasibility of identifying a new quantitative imaging marker based on false-positives generated by a computer-aided detection (CAD) scheme to help predict short-term breast cancer risk. An image dataset including four view mammograms acquired from 1044 women was retrospectively assembled. All mammograms were originally interpreted as negative by radiologists. In the next subsequent mammography screening, 402 women were diagnosed with breast cancer and 642 remained negative. An existing CAD scheme was applied ‘as is’ to process each image. From CAD-generated results, four detection features including the total number of (1) initial detection seeds and (2) the final detected false-positive regions, (3) average and (4) sum of detection scores, were computed from each image. Then, by combining the features computed from two bilateral images of left and right breasts from either craniocaudal or mediolateral oblique view, two logistic regression models were trained and tested using a leave-one-case-out cross-validation method to predict the likelihood of each testing case being positive in the next subsequent screening. The new prediction model yielded the maximum prediction accuracy with an area under a ROC curve of AUC  =  0.65  ±  0.017 and the maximum adjusted odds ratio of 4.49 with a 95% confidence interval of (2.95, 6.83). The results also showed an increasing trend in the adjusted odds ratio and risk prediction scores (p  breast cancer risk.

  9. Comparison of standard reading and computer aided detection (CAD) on a national proficiency test of screening mammography

    International Nuclear Information System (INIS)

    Ciatto, Stefano; Del Turco, Marco Rosselli; Risso, Gabriella; Catarzi, Sandra; Bonardi, Rita; Viterbo, Valeria; Gnutti, Pierangela; Guglielmoni, Barbara; Pinelli, Lelio; Pandiscia, Anna; Navarra, Francesco; Lauria, Adele; Palmiero, Rosa; Indovina, Pietro Luigi

    2003-01-01

    Objective: To evaluate the role of computer aided detection (CAD) in improving the interpretation of screening mammograms Material and methods: Ten radiologists underwent a proficiency test of screening mammography first by conventional reading and then with the help of CAD. Radiologists were blinded to test results for the whole study duration. Results of conventional and CAD reading were compared in terms of sensitivity and recall rate. Double reading was simulated combining conventional readings of four expert radiologists and compared with CAD reading. Results: Considering all ten readings, cancer was identified in 146 or 153 of 170 cases (85.8 vs. 90.0%; χ 2 =0.99, df=1, P=0.31) and recalls were 106 or 152 of 1330 cases (7.9 vs. 11.4%; χ 2 =8.69, df=1, P=0.003) at conventional or CAD reading, respectively. CAD reading was essentially the same (sensitivity 97.0 vs. 96.0%; χ 2 =7.1, df=1, P=0.93; recall rate 10.7 vs. 10.6%; χ 2 =1.5, df=1, P=0.96) as compared with simulated conventional double reading. Conclusion: CAD reading seems to improve the sensitivity of conventional reading while reducing specificity, both effects being of limited size. CAD reading had almost the same performance of simulated conventional double reading, suggesting a possible use of CAD which needs to be confirmed by further studies inclusive of cost-effective analysis

  10. The effect of computer-aided detection markers on visual search and reader performance during concurrent reading of CT colonography

    International Nuclear Information System (INIS)

    Helbren, Emma; Taylor, Stuart A.; Fanshawe, Thomas R.; Mallett, Susan; Phillips, Peter; Boone, Darren; Gale, Alastair; Altman, Douglas G.; Manning, David; Halligan, Steve

    2015-01-01

    We aimed to identify the effect of computer-aided detection (CAD) on visual search and performance in CT Colonography (CTC) of inexperienced and experienced readers. Fifteen endoluminal CTC examinations were recorded, each with one polyp, and two videos were generated, one with and one without a CAD mark. Forty-two readers (17 experienced, 25 inexperienced) interpreted the videos during infrared visual search recording. CAD markers and polyps were treated as regions of interest in data processing. This multi-reader, multi-case study was analysed using multilevel modelling. CAD drew readers' attention to polyps faster, accelerating identification times: median 'time to first pursuit' was 0.48 s (IQR 0.27 to 0.87 s) with CAD, versus 0.58 s (IQR 0.35 to 1.06 s) without. For inexperienced readers, CAD also held visual attention for longer. All visual search metrics used to assess visual gaze behaviour demonstrated statistically significant differences when ''with'' and ''without'' CAD were compared. A significant increase in the number of correct polyp identifications across all readers was seen with CAD (74 % without CAD, 87 % with CAD; p < 0.001). CAD significantly alters visual search and polyp identification in readers viewing three-dimensional endoluminal CTC. For polyp and CAD marker pursuit times, CAD generally exerted a larger effect on inexperienced readers. (orig.)

  11. The effect of computer-aided detection markers on visual search and reader performance during concurrent reading of CT colonography

    Energy Technology Data Exchange (ETDEWEB)

    Helbren, Emma; Taylor, Stuart A. [University College London, Centre for Medical Imaging, London (United Kingdom); Fanshawe, Thomas R.; Mallett, Susan [University of Oxford, Nuffield Department of Primary Care Health Sciences, Oxford (United Kingdom); Phillips, Peter [University of Cumbria, Health and Medical Sciences Group, Lancaster (United Kingdom); Boone, Darren [Colchester Hospital University NHS Foundation Trust and Anglia University, Colchester (United Kingdom); Gale, Alastair [Loughborough University, Applied Vision Research Centre, Loughborough (United Kingdom); Altman, Douglas G. [University of Oxford, Centre for Statistics in Medicine, Oxford (United Kingdom); Manning, David [Lancaster University, Lancaster Medical School, Faculty of Health and Medicine, Lancaster (United Kingdom); Halligan, Steve [University College London, Centre for Medical Imaging, London (United Kingdom); University College Hospital, Gastrointestinal Radiology, University College London, Centre for Medical Imaging, Podium Level 2, London, NW1 2BU (United Kingdom)

    2015-06-01

    We aimed to identify the effect of computer-aided detection (CAD) on visual search and performance in CT Colonography (CTC) of inexperienced and experienced readers. Fifteen endoluminal CTC examinations were recorded, each with one polyp, and two videos were generated, one with and one without a CAD mark. Forty-two readers (17 experienced, 25 inexperienced) interpreted the videos during infrared visual search recording. CAD markers and polyps were treated as regions of interest in data processing. This multi-reader, multi-case study was analysed using multilevel modelling. CAD drew readers' attention to polyps faster, accelerating identification times: median 'time to first pursuit' was 0.48 s (IQR 0.27 to 0.87 s) with CAD, versus 0.58 s (IQR 0.35 to 1.06 s) without. For inexperienced readers, CAD also held visual attention for longer. All visual search metrics used to assess visual gaze behaviour demonstrated statistically significant differences when ''with'' and ''without'' CAD were compared. A significant increase in the number of correct polyp identifications across all readers was seen with CAD (74 % without CAD, 87 % with CAD; p < 0.001). CAD significantly alters visual search and polyp identification in readers viewing three-dimensional endoluminal CTC. For polyp and CAD marker pursuit times, CAD generally exerted a larger effect on inexperienced readers. (orig.)

  12. An automated tuberculosis screening strategy combining X-ray-based computer-aided detection and clinical information

    Science.gov (United States)

    Melendez, Jaime; Sánchez, Clara I.; Philipsen, Rick H. H. M.; Maduskar, Pragnya; Dawson, Rodney; Theron, Grant; Dheda, Keertan; van Ginneken, Bram

    2016-04-01

    Lack of human resources and radiological interpretation expertise impair tuberculosis (TB) screening programmes in TB-endemic countries. Computer-aided detection (CAD) constitutes a viable alternative for chest radiograph (CXR) reading. However, no automated techniques that exploit the additional clinical information typically available during screening exist. To address this issue and optimally exploit this information, a machine learning-based combination framework is introduced. We have evaluated this framework on a database containing 392 patient records from suspected TB subjects prospectively recruited in Cape Town, South Africa. Each record comprised a CAD score, automatically computed from a CXR, and 12 clinical features. Comparisons with strategies relying on either CAD scores or clinical information alone were performed. Our results indicate that the combination framework outperforms the individual strategies in terms of the area under the receiving operating characteristic curve (0.84 versus 0.78 and 0.72), specificity at 95% sensitivity (49% versus 24% and 31%) and negative predictive value (98% versus 95% and 96%). Thus, it is believed that combining CAD and clinical information to estimate the risk of active disease is a promising tool for TB screening.

  13. Computer-aided detection of colorectal polyps: can it improve sensitivity of less-experienced readers? Preliminary findings.

    Science.gov (United States)

    Baker, Mark E; Bogoni, Luca; Obuchowski, Nancy A; Dass, Chandra; Kendzierski, Renee M; Remer, Erick M; Einstein, David M; Cathier, Pascal; Jerebko, Anna; Lakare, Sarang; Blum, Andrew; Caroline, Dina F; Macari, Michael

    2007-10-01

    To determine whether computer-aided detection (CAD) applied to computed tomographic (CT) colonography can help improve sensitivity of polyp detection by less-experienced radiologist readers, with colonoscopy or consensus used as the reference standard. The release of the CT colonographic studies was approved by the individual institutional review boards of each institution. Institutions from the United States were HIPAA compliant. Written informed consent was waived at all institutions. The CT colonographic studies in 30 patients from six institutions were collected; 24 images depicted at least one confirmed polyp 6 mm or larger (39 total polyps) and six depicted no polyps. By using an investigational software package, seven less-experienced readers from two institutions evaluated the CT colonographic images and marked or scored polyps by using a five-point scale before and after CAD. The time needed to interpret the CT colonographic findings without CAD and then to re-evaluate them with CAD was recorded. For each reader, the McNemar test, adjusted for clustered data, was used to compare sensitivities for readers without and with CAD; a Wilcoxon signed-rank test was used to analyze the number of false-positive results per patient. The average sensitivity of the seven readers for polyp detection was significantly improved with CAD-from 0.810 to 0.908 (P=.0152). The number of false-positive results per patient without and with CAD increased from 0.70 to 0.96 (95% confidence interval for the increase: -0.39, 0.91). The mean total time for the readings was 17 minutes 54 seconds; for interpretation of CT colonographic findings alone, the mean time was 14 minutes 16 seconds; and for review of CAD findings, the mean time was 3 minutes 38 seconds. Results of this feasibility study suggest that CAD for CT colonography significantly improves per-polyp detection for less-experienced readers. Copyright (c) RSNA, 2007.

  14. Computer-aided topological analysis of Nd-Fe-B ternary system

    International Nuclear Information System (INIS)

    Liu, G.; Xu, P.; Zhang, W.

    1993-01-01

    A three-dimensional partially matrixed topological model of the Nd-Fe-B ternary phase diagram has been established based on experimental results assessed comprehensively with the aid of a computer-aided design and graphic and graphics software, AutoCAD (R10), and application programs developed in this work. Vertical sections at 5.88 at.% B, Nd:B = 1:1, Fe-Nd/sub 2/Fe/sub 14/B-Nd, Nd/sub 2/Fe/sub 17/-Nd/sub 2/Fe/sub 7/B/sub 6/ have been cut out from the model and the corresponding phase relationships have been analyzed. Among them, those on the Nd-rich protons of both the sections at 5.88 at.% B and Nd:B = 2:1 and those on the Nd/sub 2/Fe/sub 14/B-Nd section are given for the first time. (author)

  15. NEXUS/NASCAD- NASA ENGINEERING EXTENDIBLE UNIFIED SOFTWARE SYSTEM WITH NASA COMPUTER AIDED DESIGN

    Science.gov (United States)

    Purves, L. R.

    1994-01-01

    NEXUS, the NASA Engineering Extendible Unified Software system, is a research set of computer programs designed to support the full sequence of activities encountered in NASA engineering projects. This sequence spans preliminary design, design analysis, detailed design, manufacturing, assembly, and testing. NEXUS primarily addresses the process of prototype engineering, the task of getting a single or small number of copies of a product to work. Prototype engineering is a critical element of large scale industrial production. The time and cost needed to introduce a new product are heavily dependent on two factors: 1) how efficiently required product prototypes can be developed, and 2) how efficiently required production facilities, also a prototype engineering development, can be completed. NEXUS extendibility and unification are achieved by organizing the system as an arbitrarily large set of computer programs accessed in a common manner through a standard user interface. The NEXUS interface is a multipurpose interactive graphics interface called NASCAD (NASA Computer Aided Design). NASCAD can be used to build and display two and three-dimensional geometries, to annotate models with dimension lines, text strings, etc., and to store and retrieve design related information such as names, masses, and power requirements of components used in the design. From the user's standpoint, NASCAD allows the construction, viewing, modification, and other processing of data structures that represent the design. Four basic types of data structures are supported by NASCAD: 1) three-dimensional geometric models of the object being designed, 2) alphanumeric arrays to hold data ranging from numeric scalars to multidimensional arrays of numbers or characters, 3) tabular data sets that provide a relational data base capability, and 4) procedure definitions to combine groups of system commands or other user procedures to create more powerful functions. NASCAD has extensive abilities to

  16. Integrated computer aided design simulation and manufacture

    OpenAIRE

    Diko, Faek

    1989-01-01

    Computer Aided Design (CAD) and Computer Aided Manufacture (CAM) have been investigated and developed since twenty years as standalone systems. A large number of very powerful but independent packages have been developed for Computer Aided Design,Aanlysis and Manufacture. However, in most cases these packages have poor facility for communicating with other packages. Recently attempts have been made to develop integrated CAD/CAM systems and many software companies a...

  17. Implementation of a computer-aided detection tool for quantification of intracranial radiologic markers on brain CT images

    Science.gov (United States)

    Aghaei, Faranak; Ross, Stephen R.; Wang, Yunzhi; Wu, Dee H.; Cornwell, Benjamin O.; Ray, Bappaditya; Zheng, Bin

    2017-03-01

    Aneurysmal subarachnoid hemorrhage (aSAH) is a form of hemorrhagic stroke that affects middle-aged individuals and associated with significant morbidity and/or mortality especially those presenting with higher clinical and radiologic grades at the time of admission. Previous studies suggested that blood extravasated after aneurysmal rupture was a potentially clinical prognosis factor. But all such studies used qualitative scales to predict prognosis. The purpose of this study is to develop and test a new interactive computer-aided detection (CAD) tool to detect, segment and quantify brain hemorrhage and ventricular cerebrospinal fluid on non-contrasted brain CT images. First, CAD segments brain skull using a multilayer region growing algorithm with adaptively adjusted thresholds. Second, CAD assigns pixels inside the segmented brain region into one of three classes namely, normal brain tissue, blood and fluid. Third, to avoid "black-box" approach and increase accuracy in quantification of these two image markers using CT images with large noise variation in different cases, a graphic User Interface (GUI) was implemented and allows users to visually examine segmentation results. If a user likes to correct any errors (i.e., deleting clinically irrelevant blood or fluid regions, or fill in the holes inside the relevant blood or fluid regions), he/she can manually define the region and select a corresponding correction function. CAD will automatically perform correction and update the computed data. The new CAD tool is now being used in clinical and research settings to estimate various quantitatively radiological parameters/markers to determine radiological severity of aSAH at presentation and correlate the estimations with various homeostatic/metabolic derangements and predict clinical outcome.

  18. Development of a computer-aided diagnostic scheme for detection of interval changes in successive whole-body bone scans

    International Nuclear Information System (INIS)

    Shiraishi, Junji; Li Qiang; Appelbaum, Daniel; Pu Yonglin; Doi, Kunio

    2007-01-01

    Bone scintigraphy is the most frequent examination among various diagnostic nuclear medicine procedures. It is a well-established imaging modality for the diagnosis of osseous metastasis and for monitoring osseous tumor response to chemotherapy and radiation therapy. Although the sensitivity of bone scan examinations for detection of bone abnormalities has been considered to be relatively high, it is time consuming to identify multiple lesions such as bone metastases of prostate and breast cancers. In addition, it is very difficult to detect subtle interval changes between two successive abnormal bone scans, because of variations in patient conditions, the accumulation of radioisotopes during each examination, and the image quality of gamma cameras. Therefore, we developed a new computer-aided diagnostic (CAD) scheme for the detection of interval changes in successive whole-body bone scans by use of a temporal subtraction image which was obtained with a nonlinear image-warping technique. We carried out 58 pairs of successive bone scans in which each scan included both posterior and anterior views. We determined 107 'gold-standard' interval changes among the 58 pairs based on the consensus of three radiologists. Our computerized scheme consisted of seven steps, i.e., initial image density normalization on each image, image matching for the paired images, temporal subtraction by use of the nonlinear image-warping technique, initial detection of interval changes by use of temporal-subtraction images, image feature extraction of candidates of interval changes, rule-based tests by use of 16 image features for removing some false positives, and display of the computer output for identified interval changes. One hundred seven gold standard interval changes included 71 hot lesions (uptake was increased compared with the previous scan, or there was new uptake in the current scan) and 36 cold lesions (uptake was decreased or disappeared) for anterior and posterior views. The

  19. Single reading with computer-aided detection performed by selected radiologists in a breast cancer screening program

    Energy Technology Data Exchange (ETDEWEB)

    Bargalló, Xavier, E-mail: xbarga@clinic.cat [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/ Villarroel, 170, 08036 Barcelona (Spain); Santamaría, Gorane; Amo, Montse del; Arguis, Pedro [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/ Villarroel, 170, 08036 Barcelona (Spain); Ríos, José [Biostatistics and Data Management Core Facility, IDIBAPS, (Hospital Clinic) C/ Mallorca, 183. Floor -1. Office #60. 08036 Barcelona (Spain); Grau, Jaume [Preventive Medicine and Epidemiology Unit, Hospital Clínic de Barcelona, C/ Villarroel, 170, 08036 Barcelona (Spain); Burrel, Marta; Cores, Enrique; Velasco, Martín [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/ Villarroel, 170, 08036 Barcelona (Spain)

    2014-11-15

    Highlights: • 1-The cancer detection rate of the screening program improved using a single reading protocol by experienced radiologists assisted by CAD. • 2-The cancer detection rate improved at the cost of increasing recall rate. • 3-CAD, used by breast radiologists, did not help to detect more cancers. - Abstract: Objectives: To assess the impact of shifting from a standard double reading plus arbitration protocol to a single reading by experienced radiologists assisted by computer-aided detection (CAD) in a breast cancer screening program. Methods: This was a prospective study approved by the ethics committee. Data from 21,321 consecutive screening mammograms in incident rounds (2010–2012) were read following a single reading plus CAD protocol and compared with data from 47,462 consecutive screening mammograms in incident rounds (2004–2010) that were interpreted following a double reading plus arbitration protocol. For the single reading, radiologists were selected on the basis of the appraisement of their previous performance. Results: Period 2010–2012 vs. period 2004–2010: Cancer detection rate (CDR): 6.1‰ (95% confidence interval: 5.1–7.2) vs. 5.25‰; Recall rate (RR): 7.02% (95% confidence interval: 6.7–7.4) vs. 7.24% (selected readers before arbitration) and vs. 3.94 (all readers after arbitration); Predictive positive value of recall: 8.69% vs. 13.32%. Average size of invasive cancers: 14.6 ± 9.5 mm vs. 14.3 ± 9.5 mm. Stage: 0 (22.3/26.1%); I (59.2/50.8%); II (19.2/17.1%); III (3.1/3.3%); IV (0/1.9%). Specialized breast radiologists performed better than general radiologists. Conclusions: The cancer detection rate of the screening program improved using a single reading protocol by experienced radiologists assisted by CAD, at the cost of a moderate increase of the recall rate mainly related to the lack of arbitration.

  20. Computer-aided diagnosis (CAD) of subsolid nodules: Evaluation of a commercial CAD system

    International Nuclear Information System (INIS)

    Benzakoun, Joseph; Bommart, Sébastien; Coste, Joël; Chassagnon, Guillaume; Lederlin, Mathieu; Boussouar, Samia

    2016-01-01

    Highlights: • CAD sensitivity is still limited for automated detection of subsolid nodules. • CAD detection rate is higher for part-solid than for pure ground-glass nodules. • Part-solid nodule detection is not better for nodules with larger solid component. - Abstract: Objectives: To evaluate the performance of a commercially available CAD system for automated detection and measurement of subsolid nodules. Materials and methods: The CAD system was tested on 50 pure ground-glass and 50 part-solid nodules (median diameter: 17 mm) previously found on standard-dose CT scans in 100 different patients. True nodule detection and the total number of CAD marks were evaluated at different sensitivity settings. The influence of nodule and CT acquisition characteristics was analyzed with logistic regression. Software and manually measured diameters were compared with Spearman and Bland-Altman methods. Results: With sensitivity adjusted for 3-mm nodule detection, 50/100 (50%) subsolid nodules were detected, at the average cost of 17 CAD marks per CT. These figures were respectively 26/100 (26%) and 2 at the 5-mm setting. At the highest sensitivity setting (2-mm nodule detection), the average number of CAD marks per CT was 41 but the nodule detection rate only increased to 54%. Part–solid nodules were better detected than pure ground glass nodules: 36/50 (72%) versus 14/50 (28%) at the 3-mm setting (p < 0.0001), with no influence of the solid component size. Except for the type (i.e. part solid or pure ground glass), no other nodule characteristic influenced the detection rate. High-quality segmentation was obtained for 79 nodules, which for automated measurements correlated well with manual measurements (rho = 0.90[0.84–0.93]). All part-solid nodules had software-measured attenuation values above −671 Hounsfield units (HU). Conclusion: The detection rate of subsolid nodules by this CAD system was insufficient, but high-quality segmentation was obtained in 79% of

  1. Computer-aided diagnosis (CAD) of subsolid nodules: Evaluation of a commercial CAD system

    Energy Technology Data Exchange (ETDEWEB)

    Benzakoun, Joseph, E-mail: benzakoun.joseph@gmail.com [Hôpital Hôtel-Dieu, 1 parvis Notre-Dame, 75004 Paris (France); Université Paris Descartes, 12 rue de l’Ecole de Médecine, 75006 Paris (France); Bommart, Sébastien, E-mail: s-bommart@chu-montpellier.fr [CHU de Montpellier, 191 avenue du Doyen Gaston Giraud, 34000 Montpellier (France); INSERM U 1046, 371 avenue du Doyen G. Giraud, 34000 Montpellier (France); Coste, Joël, E-mail: joel.coste@htd.aphp.fr [Hôpital Hôtel-Dieu, 1 parvis Notre-Dame, 75004 Paris (France); Université Paris Descartes, 12 rue de l’Ecole de Médecine, 75006 Paris (France); Chassagnon, Guillaume, E-mail: gchassagnon@gmail.com [Université Paris Descartes, 12 rue de l’Ecole de Médecine, 75006 Paris (France); Hôpital Cochin, Radiologie, 27 rue du Faubourg Saint Jacques, 75014 Paris (France); Lederlin, Mathieu, E-mail: mathieu.lederlin@chu-rennes.fr [CHU de Rennes, Radiologie, 2 Rue Henri le Guilloux, 35000 Rennes (France); Université de Rennes 1, 9 Rue Jean Macé, 35000 Rennes (France); Boussouar, Samia, E-mail: samiaboussouar@gmail.com [Université Paris Descartes, 12 rue de l’Ecole de Médecine, 75006 Paris (France); Hôpital Européen Georges Pompidou, 20 Rue Leblanc, 75015 Paris (France); and others

    2016-10-15

    Highlights: • CAD sensitivity is still limited for automated detection of subsolid nodules. • CAD detection rate is higher for part-solid than for pure ground-glass nodules. • Part-solid nodule detection is not better for nodules with larger solid component. - Abstract: Objectives: To evaluate the performance of a commercially available CAD system for automated detection and measurement of subsolid nodules. Materials and methods: The CAD system was tested on 50 pure ground-glass and 50 part-solid nodules (median diameter: 17 mm) previously found on standard-dose CT scans in 100 different patients. True nodule detection and the total number of CAD marks were evaluated at different sensitivity settings. The influence of nodule and CT acquisition characteristics was analyzed with logistic regression. Software and manually measured diameters were compared with Spearman and Bland-Altman methods. Results: With sensitivity adjusted for 3-mm nodule detection, 50/100 (50%) subsolid nodules were detected, at the average cost of 17 CAD marks per CT. These figures were respectively 26/100 (26%) and 2 at the 5-mm setting. At the highest sensitivity setting (2-mm nodule detection), the average number of CAD marks per CT was 41 but the nodule detection rate only increased to 54%. Part–solid nodules were better detected than pure ground glass nodules: 36/50 (72%) versus 14/50 (28%) at the 3-mm setting (p < 0.0001), with no influence of the solid component size. Except for the type (i.e. part solid or pure ground glass), no other nodule characteristic influenced the detection rate. High-quality segmentation was obtained for 79 nodules, which for automated measurements correlated well with manual measurements (rho = 0.90[0.84–0.93]). All part-solid nodules had software-measured attenuation values above −671 Hounsfield units (HU). Conclusion: The detection rate of subsolid nodules by this CAD system was insufficient, but high-quality segmentation was obtained in 79% of

  2. Computer Aided Tracing System 「CATS」(version I)の使用手引書

    OpenAIRE

    谷 啓二; 納 俊樹; 木原 和久

    1984-01-01

    コンピューターグラフィックスの一応用として、各種の図形、表などをタブレットデジタイザーを用いて計算機に入力し、グラッフィックディスプレイ(GD)上で図形を編集、表示し、その結果をカラーハードコピーやNLP(レーザープリンター)に清書出力するソフトプログラム Computer Aided Tracing System「CATS」を開発を行なった。「CATS」におけるデータの入力は、全て日本語による全活形式を採用しているため、ユーザーはGD専用の複雑なソフトを意識することなくGD上で図形の編集が行える。本報告は「CATS」の使用手引書としてまとめたものである。...

  3. Computer Aided Prototyping System (CAPS) for Heterogeneous Systems Development and Integration

    OpenAIRE

    Luqi; Berzins, V.; Shing, M.; Nada, N.; Eagle, C.

    2000-01-01

    2000 Command and Control Research and Technology Symposium (CCRTS), June 11-13, 2000, Naval Postgraduate School, Monterey, CA This paper addresses the problem of how to produce reliable software that is also flexible and cost effective for the DoD distributed software domain. DoD software systems fall into two categories: information systems and war fighter systems. Both types of systems can be distributed, heterogeneous and network-based, consisting of a set of components running...

  4. A computer-aided audit system for respiratory therapy consult evaluations: description of a method and early results.

    Science.gov (United States)

    Kester, Lucy; Stoller, James K

    2013-05-01

    Use of respiratory therapist (RT)-guided protocols enhances allocation of respiratory care. In the context that optimal protocol use requires a system for auditing respiratory care plans to assure adherence to protocols and expertise of the RTs generating the care plan, a live audit system has been in longstanding use in our Respiratory Therapy Consult Service. Growth in the number of RT positions and the need to audit more frequently has prompted development of a new, computer-aided audit system. The number and results of audits using the old and new systems were compared (for the periods May 30, 2009 through May 30, 2011 and January 1, 2012 through May 30, 2012, respectively). In contrast to the original, live system requiring a patient visit by the auditor, the new system involves completion of a respiratory therapy care plan using patient information in the electronic medical record, both by the RT generating the care plan and the auditor. Completing audits in the new system also uses an electronic respiratory therapy management system. The degrees of concordance between the audited RT's care plans and the "gold standard" care plans using the old and new audit systems were similar. Use of the new system was associated with an almost doubling of the rate of audits (ie, 11 per month vs 6.1 per month). The new, computer-aided audit system increased capacity to audit more RTs performing RT-guided consults while preserving accuracy as an audit tool. Ensuring that RTs adhere to the audit process remains the challenge for the new system, and is the rate-limiting step.

  5. Two adults with multiple disabilities use a computer-aided telephone system to make phone calls independently.

    Science.gov (United States)

    Lancioni, Giulio E; O'Reilly, Mark F; Singh, Nirbhay N; Sigafoos, Jeff; Oliva, Doretta; Alberti, Gloria; Lang, Russell

    2011-01-01

    This study extended the assessment of a newly developed computer-aided telephone system with two participants (adults) who presented with blindness or severe visual impairment and motor or motor and intellectual disabilities. For each participant, the study was carried out according to an ABAB design, in which the A represented baseline phases and the B represented intervention phases, during which the special telephone system was available. The system involved among others a net-book computer provided with specific software, a global system for mobile communication modem, and a microswitch. Both participants learned to use the system very rapidly and managed to make phone calls independently to a variety of partners such as family members, friends and staff personnel. The results were discussed in terms of the technology under investigation (its advantages, drawbacks, and need of improvement) and the social-communication impact it can make for persons with multiple disabilities. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Computer-aided mathematical analysis of probability of intercept for ground-based communication intercept system

    Science.gov (United States)

    Park, Sang Chul

    1989-09-01

    We develop a mathematical analysis model to calculate the probability of intercept (POI) for the ground-based communication intercept (COMINT) system. The POI is a measure of the effectiveness of the intercept system. We define the POI as the product of the probability of detection and the probability of coincidence. The probability of detection is a measure of the receiver's capability to detect a signal in the presence of noise. The probability of coincidence is the probability that an intercept system is available, actively listening in the proper frequency band, in the right direction and at the same time that the signal is received. We investigate the behavior of the POI with respect to the observation time, the separation distance, antenna elevations, the frequency of the signal, and the receiver bandwidths. We observe that the coincidence characteristic between the receiver scanning parameters and the signal parameters is the key factor to determine the time to obtain a given POI. This model can be used to find the optimal parameter combination to maximize the POI in a given scenario. We expand this model to a multiple system. This analysis is conducted on a personal computer to provide the portability. The model is also flexible and can be easily implemented under different situations.

  7. Computer-Aided Design System Development of Fixed Water Distribution of Pipe Irrigation System

    OpenAIRE

    Zhou , Mingyao; Wang , Susheng; Zhang , Zhen; Chen , Lidong

    2010-01-01

    International audience; It is necessary to research a cheap and simple fixed water distribution device according to the current situation of the technology of low-pressure pipe irrigation. This article proposed a fixed water distribution device with round table based on the analysis of the hydraulic characteristics of low-pressure pipe irrigation systems. The simulation of FLUENT and GAMBIT software conducted that the flow of this structure was steady with a low head loss comparing to other t...

  8. Intelligent computer aided training systems in the real world: Making the technology accessible to the educational mainstream

    Science.gov (United States)

    Kovarik, Madeline

    1993-01-01

    Intelligent computer aided training systems hold great promise for the application of this technology to mainstream education and training. Yet, this technology, which holds such a vast potential impact for the future of education and training, has had little impact beyond the enclaves of government research labs. This is largely due to the inaccessibility of the technology to those individuals in whose hands it can have the greatest impact, teachers and educators. Simply throwing technology at an educator and expecting them to use it as an effective tool is not the answer. This paper provides a background into the use of technology as a training tool. MindLink, developed by HyperTech Systems, provides trainers with a powerful rule-based tool that can be integrated directly into a Windows application. By embedding expert systems technology it becomes more accessible and easier to master.

  9. The integration of automated knowledge acquisition with computer-aided software engineering for space shuttle expert systems

    Science.gov (United States)

    Modesitt, Kenneth L.

    1990-01-01

    A prediction was made that the terms expert systems and knowledge acquisition would begin to disappear over the next several years. This is not because they are falling into disuse; it is rather that practitioners are realizing that they are valuable adjuncts to software engineering, in terms of problem domains addressed, user acceptance, and in development methodologies. A specific problem was discussed, that of constructing an automated test analysis system for the Space Shuttle Main Engine. In this domain, knowledge acquisition was part of requirements systems analysis, and was performed with the aid of a powerful inductive ESBT in conjunction with a computer aided software engineering (CASE) tool. The original prediction is not a very risky one -- it has already been accomplished.

  10. Integration of computer-aided diagnosis/detection (CAD) results in a PACS environment using CAD-PACS toolkit and DICOM SR

    International Nuclear Information System (INIS)

    Le, Anh H.T.; Liu, Brent; Huang, H.K.

    2009-01-01

    Picture Archiving and Communication System (PACS) is a mature technology in health care delivery for daily clinical imaging service and data management. Computer-aided detection and diagnosis (CAD) utilizes computer methods to obtain quantitative measurements from medical images and clinical information to assist clinicians to assess a patient's clinical state more objectively. CAD needs image input and related information from PACS to improve its accuracy; and PACS benefits from CAD results online and available at the PACS workstation as a second reader to assist physicians in the decision making process. Currently, these two technologies remain as two separate independent systems with only minimal system integration. This paper describes a universal method to integrate CAD results with PACS in its daily clinical environment. The method is based on Health Level 7 (HL7) and Digital imaging and communications in medicine (DICOM) standards, and Integrating the Healthcare Enterprise (IHE) workflow profiles. In addition, the integration method is Health Insurance Portability and Accountability Act (HIPAA) compliant. The paper presents (1) the clinical value and advantages of integrating CAD results in a PACS environment, (2) DICOM Structured Reporting formats and some important IHE workflow profiles utilized in the system integration, (3) the methodology using the CAD-PACS integration toolkit, and (4) clinical examples with step-by-step workflows of this integration. (orig.)

  11. Computer-aided analysis of power-electronic systems simulation of a high-voltage power converter

    International Nuclear Information System (INIS)

    Bordry, F.; Isch, H.W.; Proudlock, P.

    1987-01-01

    In the study of semiconductor devices, simulation methods play an important role in both the design of systems and the analysis of their operation. The authors describe a new and efficient computer-aided package program for general power-electronic systems. The main difficulty when taking into account non-linear elements, such as semiconductors, lies in determining the existence and the relations of the elementary sequences defined by the conduction or nonconduction of these components. The method does not require a priori knowledge of the state sequences of the semiconductor nor of the commutation instants, but only the circuit structure, its parameters and the commands to the controlled switches. The simulation program computes automatically both transient and steady-state waveforms for any circuit configuration. The simulation of a high-voltage power converter is presented, both for its steady-state and transient overload conditions. This 100 kV power converter (4 MW) will feed two klystrons in parallel

  12. An expert system in C for computer-aided digital circuit design

    Science.gov (United States)

    Santos, Jorge S.

    1989-06-01

    This thesis effort documents the design, development, implementation, and test of an expert system which decomposes digital circuits into subproblems in order to detect wiring errors, which consist of improperly connected gates, missing connections, and violation of fanout or race conditions. Information needed to connect chips together is viewed as knowledge base information for the expert system. Information such type as number of pins, value of each pin (input, output, power, ground, clock), fanout for a particular type of chip are retrieved from a central database where they are represented. Implementation was done in the C programming language, which although is not design specially for dealing with problems in the Artificial Intelligence (AI) field could be used with success. An integration with a graphics package and a central database was achieved. Tests conducted with the system running in a personal computer Zenith 248 and compatible microcomputers under the Disk Operational System (DOS) version 3.2 proved the portability and efficiency of the expert system. A user's manual is included for the operation of the InterConnect Expert System (ICE).

  13. Detection of a possible epilepsy focus in a preoperated patient by perfusion SPECT and computer-aided subtraction analysis

    International Nuclear Information System (INIS)

    Apostolova, I.; Wilke, F.; Clausen, M.; Buchert, R.; Lindenau, M.; Stodieck, S.; Fiehler, J.; Heese, O.

    2008-01-01

    Ictal perfusion SPECT with either 9 9mTc-hexamethylpropylene amine oxime (HMPAO) or 9 9mTc-ethylcysteinate dimer (ECD) has been reported to provide very good sensitivity for the determination of the SOA in fTLE. Sensitivity of interictal perfusion SPECT is much lower. However, interictal perfusion SPECT might enhance the specificity of ictal SPECT findings by improving the discrimination between seizure related local hyperperfusion and intersubject variability of perfusion (physiologic hyperperfusion). In addition, the combination of interictal and ictal perfusion SPECT might provide improved sensitivity compared to ictal SPECT alone, particularly when computer-aided subtraction of ictal and interictal SPECT is used instead of traditional side-by-side visual comparison. The combination of ictal and interictal perfusion SPECT eliminates not only physiological inter-subject variance, but it can also eliminate severe partial volume effects. Computer-aided subtraction analysis appears particularly useful in this case

  14. Detection of a possible epilepsy focus in a preoperated patient by perfusion SPECT and computer-aided subtraction analysis

    Energy Technology Data Exchange (ETDEWEB)

    Apostolova, I.; Wilke, F.; Clausen, M.; Buchert, R. [Univ. Medical Center Hamburg-Eppendorf (Germany). Dept. of Nuclear Medicine; Lindenau, M.; Stodieck, S. [Protestant Hospital Alsterdorf, Hamburg (Germany). Dept. of Neurology and Epileptology; Fiehler, J. [Univ. Medical Center Hamburg-Eppendorf (Germany). Dept. of Neuroradiology; Heese, O. [Univ. Medical Center Hamburg-Eppendorf (Germany). Neurological Surgery

    2008-07-01

    Ictal perfusion SPECT with either {sup 9}9mTc-hexamethylpropylene amine oxime (HMPAO) or {sup 9}9mTc-ethylcysteinate dimer (ECD) has been reported to provide very good sensitivity for the determination of the SOA in fTLE. Sensitivity of interictal perfusion SPECT is much lower. However, interictal perfusion SPECT might enhance the specificity of ictal SPECT findings by improving the discrimination between seizure related local hyperperfusion and intersubject variability of perfusion (physiologic hyperperfusion). In addition, the combination of interictal and ictal perfusion SPECT might provide improved sensitivity compared to ictal SPECT alone, particularly when computer-aided subtraction of ictal and interictal SPECT is used instead of traditional side-by-side visual comparison. The combination of ictal and interictal perfusion SPECT eliminates not only physiological inter-subject variance, but it can also eliminate severe partial volume effects. Computer-aided subtraction analysis appears particularly useful in this case.

  15. Performance of fusion algorithms for computer-aided detection and classification of mines in very shallow water obtained from testing in navy Fleet Battle Exercise-Hotel 2000

    Science.gov (United States)

    Ciany, Charles M.; Zurawski, William; Kerfoot, Ian

    2001-10-01

    The performance of Computer Aided Detection/Computer Aided Classification (CAD/CAC) Fusion algorithms on side-scan sonar images was evaluated using data taken at the Navy's's Fleet Battle Exercise-Hotel held in Panama City, Florida, in August 2000. A 2-of-3 binary fusion algorithm is shown to provide robust performance. The algorithm accepts the classification decisions and associated contact locations form three different CAD/CAC algorithms, clusters the contacts based on Euclidian distance, and then declares a valid target when a clustered contact is declared by at least 2 of the 3 individual algorithms. This simple binary fusion provided a 96 percent probability of correct classification at a false alarm rate of 0.14 false alarms per image per side. The performance represented a 3.8:1 reduction in false alarms over the best performing single CAD/CAC algorithm, with no loss in probability of correct classification.

  16. Investigation of computer-aided diagnosis system for bone scans: a retrospective analysis in 406 patients.

    Science.gov (United States)

    Tokuda, Osamu; Harada, Yuko; Ohishi, Yona; Matsunaga, Naofumi; Edenbrandt, Lars

    2014-05-01

    The aim of this study was to investigate the diagnostic ability of a completely automated computer-assisted diagnosis (CAD) system to detect metastases in bone scans by two patterns: one was per region, and the other was per patient. This study included 406 patients with suspected metastatic bone tumors who underwent whole-body bone scans that were analyzed by the automated CAD system. The patients were divided into four groups: a group with prostatic cancer (N = 71), breast cancer (N = 109), males with other cancers (N = 153), and females with other cancers (N = 73). We investigated the bone scan index and artificial neural network (ANN), which are parameters that can be used to classify bone scans to determine whether there are metastases. The sensitivities, specificities, positive predictive value (PPV), negative predictive value (NPV), and accuracies for the four groups were compared. Receiver operating characteristic (ROC) analyses of region-based ANN were performed to compare the diagnostic performance of the automated CAD system. There were no significant differences in the sensitivity, specificity, or NPV between the four groups. The PPVs of the group with prostatic cancer (51.0 %) were significantly higher than those of the other groups (P < 0.01). The accuracy of the group with prostatic cancer (81.5 %) was significantly higher than that of the group with breast cancer (68.6 %) and the females with other cancers (65.9 %) (P < 0.01). For the evaluation of the ROC analysis of region-based ANN, the highest Az values for the groups with prostatic cancer, breast cancer, males with other cancers, and females with other cancers were 0.82 (ANN = 0.4, 0.5, 0.6, 0.7, and 0.8), 0.83 (ANN = 0.7), 0.81 (ANN = 0.5), and 0.81 (ANN = 0.6), respectively. The special CAD system "BONENAVI" trained with a Japanese database appears to have significant potential in assisting physicians in their clinical routine. However, an improved CAD system depending on the primary lesion

  17. Investigation of computer-aided diagnosis system for bone scans. A retrospective analysis in 406 patients

    International Nuclear Information System (INIS)

    Tokuda, Osamu; Harada, Yuko; Ohishi, Yona; Matsunaga, Naofumi; Edenbrandt, L.

    2014-01-01

    The aim of this study was to investigate the diagnostic ability of a completely automated computer-assisted diagnosis (CAD) system to detect metastases in bone scans by two patterns: one was per region, and the other was per patient. This study included 406 patients with suspected metastatic bone tumors who underwent whole-body bone scans that were analyzed by the automated CAD system. The patients were divided into four groups: a group with prostatic cancer (N=71), breast cancer (N=109), males with other cancers (N=153), and females with other cancers (N=73). We investigated the bone scan index and artificial neural network (ANN), which are parameters that can be used to classify bone scans to determine whether there are metastases. The sensitivities, specificities, positive predictive value (PPV), negative predictive value (NPV), and accuracies for the four groups were compared. Receiver operating characteristic (ROC) analyses of region-based ANN were performed to compare the diagnostic performance of the automated CAD system. There were no significant differences in the sensitivity, specificity, or NPV between the four groups. The Pps of the group with prostatic cancer (51.0%) were significantly higher than those of the other groups (P < 0.01). The accuracy of the group with prostatic cancer (81.5%) was significantly higher than that of the group with breast cancer (68.6%) and the females with other cancers (65.9%) (P < 0.01). For the evaluation of the Roc analysis of region-based Ann, the highest Az values for the groups with prostatic cancer, breast cancer, males with other cancers, and females with other cancers were 0.82 (Ann=0.4, 0.5, 0.6, 0.7, and 0.8), 0.83 (Ann=0.7), 0.81 (Ann=0.5), and 0.81 (Ann=0.6), respectively. The special CAD system 'Bovine' trained with a Japanese database appears to have significant potential in assisting physicians in their clinical routine. However, an improved CAD system depending on the primary lesion of the cancer is

  18. Evaluation of computer-aided detection and dual energy software in detection of peripheral pulmonary embolism on dual-energy pulmonary CT angiography

    International Nuclear Information System (INIS)

    Lee, Choong Wook; Seo, Joon Beom; Song, Jae-Woo; Kim, Mi-Young; Lee, Ha Young; Park, Yang Shin; Chae, Eun Jin; Jang, Yu Mi; Kim, Namkug; Krauss, Bernard

    2011-01-01

    To evaluate the sensitivity of computer-aided detection(CAD) and dual-energy software('Lung PBV', 'Lung Vessels') for detecting peripheral pulmonary embolism(PE). Between Jan-2007 and Jan-2008, 309 patients underwent dual-energy CT angiography(DECTA) for the evaluation of suspected PE. Among them, 37 patients were retrospectively selected; 21 with PE at segmental-or-below levels and 16 without PE according to clinical reports. A standard computer assisted detection (CAD) package and two new types of software('Lung PBV', 'Lung Vessels') were applied on a dedicated workstation. This resulted in four alternative tests for detecting PE: DECTA alone and DECTA with CAD, 'Lung Vessels' and 'Lung PBV'. Two radiologists independently read all cases at different reading sessions. Two thoracic radiologists set the reference standard by combining all information from DECTA and software. The sensitivity of detection for all, segmental and subsegmental-or-below PE were assessed. The reference standard contained 136 PE(segmental 65, subsegmental-or-below 71). With DECTA alone, the sensitivity of detection for all, segmental and subsegmental-or-below pulmonary arteries was 54.5%/73.7%/34.4%; DECTA with CAD, 57.8%/76.8%/37.9%; DECTA with 'Lung PBV', 61.1%/79.9%/41.4%; DECTA with 'Lung Vessels', 64.0%/78.3%/48.5% respectively. The use of CAD, Lung Vessels and Lung PBV shows improved capability to detect peripheral PE. (orig.)

  19. Computer-Aided Parts Estimation

    OpenAIRE

    Cunningham, Adam; Smart, Robert

    1993-01-01

    In 1991, Ford Motor Company began deployment of CAPE (computer-aided parts estimating system), a highly advanced knowledge-based system designed to generate, evaluate, and cost automotive part manufacturing plans. cape is engineered on an innovative, extensible, declarative process-planning and estimating knowledge representation language, which underpins the cape kernel architecture. Many manufacturing processes have been modeled to date, but eventually every significant process in motor veh...

  20. Computer aided safety analysis

    International Nuclear Information System (INIS)

    1988-05-01

    The document reproduces 20 selected papers from the 38 papers presented at the Technical Committee/Workshop on Computer Aided Safety Analysis organized by the IAEA in co-operation with the Institute of Atomic Energy in Otwock-Swierk, Poland on 25-29 May 1987. A separate abstract was prepared for each of these 20 technical papers. Refs, figs and tabs

  1. Building a computer-aided design capability using a standard time share operating system

    Science.gov (United States)

    Sobieszczanski, J.

    1975-01-01

    The paper describes how an integrated system of engineering computer programs can be built using a standard commercially available operating system. The discussion opens with an outline of the auxiliary functions that an operating system can perform for a team of engineers involved in a large and complex task. An example of a specific integrated system is provided to explain how the standard operating system features can be used to organize the programs into a simple and inexpensive but effective system. Applications to an aircraft structural design study are discussed to illustrate the use of an integrated system as a flexible and efficient engineering tool. The discussion concludes with an engineer's assessment of an operating system's capabilities and desirable improvements.

  2. Computer-aided N. M. R. spectra interpretation. I. An artificial intelligence system

    Energy Technology Data Exchange (ETDEWEB)

    Vida, M [Central N.M.R. Laboratory, Slovak Technical University, Bratislava (Czechoslovakia)

    1980-03-01

    Some desirable hardware and software features of an artificial intelligence system tailored to the needs of a modern computerized n.m.r. laboratory are discussed. A system corresponding to this idea is described.

  3. Performance of computer-aided diagnosis for detection of lacunar infarcts on brain MR images: ROC analysis of radiologists' detection

    Energy Technology Data Exchange (ETDEWEB)

    Uchiyama, Y.; Yokoyama, R.; Hara, T.; Fujita, H. [Dept. of Intelligent Image Information, Graduate Scholl of Medicine, Gifu Univ. (Japan); Asano, T.; Kato, H.; Hoshi, H. [Dept. of Radiology, Graduate Scholl of Medicine, Gifu Univ. (Japan); Yamakawa, H.; Iwama, T. [Dept. of Neurosurgery, Graduate Scholl of Medicine, Gifu Univ. (Japan); Ando, H. [Dept. of Neurosurgery, Gifu Municipal Hospital (Japan); Yamakawa, H. [Dept. of Emergency and Critical Care Medicine, Chuno-Kousei Hospital (Japan)

    2007-06-15

    The detection and management of asymptomatic lacunar infarcts on magnetic resonance (MR) images are important tasks for radiologists to ensure the prevention of sever cerebral infarctions. However, accurate identification of lacunar infarcts is a difficult. Therefore, we developed a computer-aided diagnosis (CAD) scheme for detection of lacunar infarcts. The purpose of this study was to evaluate radiologists' performance in detection of lacunar infarcts without and with use of CAD scheme. 30 T1- and 30 T2- weighted images obtained from 30 patients were used for an observer study, which were consisted of 15 cases with a single lacunar infarct and 15 cases without any lacunar infarct. Six radiologists participated in the observer study. They interpreted lacunar infarcts first without and then with use of the scheme. For all six observers, average area under the receiver operating characteristic curve value was increased from 0.920 to 0.965 when they used the computer output. This CAD scheme might have the potential to improve the accuracy of radiologists' performance in the detection of lacunar infarcts on MR images. (orig.)

  4. A computer-aided collection and construction system of terminology based on a statistically built knowledge base

    International Nuclear Information System (INIS)

    Konishi, O.; Miyahara, A.

    1988-04-01

    Since a terminology is a system of concepts to which terms should be assigned, automatic processings of such concepts seem to be difficult to be realized. In this paper, we propose a computer-aided collection and construction system of terminology which creates automatically a knowledge base using the technical terms and their frequency of appearance information extracted from a bibliographic database and selects the terminologies based on the knowledge base. The experts in specialized fields can be offered a set of candidates for the technical terms with the system and determined needed terminologies through the following important procedures: 1) the relations among important concepts in a specified field can be extracted; 2) the concepts in the lower classes can be searched by specifying those in the upper classes; 3) the important terms can be distinguished from the basic terms and then the most important terms can be selected. An application of the present system to nuclear fusion research is described in detail. (author)

  5. Computer-aided detection of pulmonary embolism: Influence on radiologists' detection performance with respect to vessel segments

    International Nuclear Information System (INIS)

    Das, Marco; Muehlenbruch, Georg; Helm, Anita; Guenther, Rolf W.; Wildberger, Joachim E.; Bakai, Annemarie; Salganicoff, Marcos; Liang, Jianming; Wolf, Matthias; Stanzel, Sven

    2008-01-01

    The purpose was to assess the sensitivity of a CAD software prototype for the detection of pulmonary embolism in MDCT chest examinations with regard to vessel level and to assess the influence on radiologists' detection performance. Forty-three patients with suspected PE were included in this retrospective study. MDCT chest examinations with a standard PE protocol were acquired at a 16-slice MDCT. All patient data were read by three radiologists (R1, R2, R3), and all thrombi were marked. A CAD prototype software was applied to all datasets, and each finding of the software was analyzed with regard to vessel level. The standard of reference was assessed in a consensus read. Sensitivity for the radiologists and CAD software was assessed. Thirty-three patients were positive for PE, with a total of 215 thrombi. The mean overall sensitivity for the CAD software alone was 83% (specificity, 80%). Radiologist sensitivity was 77% = R3, 82% = R2, and R1 = 87%. With the aid of the CAD software, sensitivities increased to 98% (R1), 93% (R2), and 92% (R3) (p<0.0001). CAD performance at the lobar level was 87%, at the segmental 90% and at the subsegmental 77%. With the use of CAD for PE, the detection performance of radiologists can be improved. (orig.)

  6. Development library of finite elements for computer-aided design system of reed sensors

    Science.gov (United States)

    Kozlov, A. S.; Shmakov, N. A.; Tkalich, V. L.; Labkovskaia, R. I.; Kalinkina, M. E.; Pirozhnikova, O. I.

    2018-05-01

    The article is devoted to the development of a modern highly reliable element base of devices for security and fire alarm systems, in particular, to the improvement of the quality of contact cores (reed and membrane) of reed sensors. Modeling of elastic sensitive elements uses quadrangular elements of plates and shells, considered in the system of curvilinear orthogonal coordinates. The developed mathematical models and the formed finite element library are designed for systems of automated design of reed switch detectors to create competitive devices alarms. The finite element library is used for the automated system production of reed switch detectors both in series production and in the implementation of individual orders.

  7. Development of a computer-aided clinical patient education system to provide appropriate individual nursing care for psychiatric patients.

    Science.gov (United States)

    Tseng, Kuan-Jui; Liou, Tsan-Hon; Chiu, Hung-Wen

    2012-06-01

    A lot of researches have proven that health education can help patients to maintain and improve their health. And it also shortens the time staying in hospital to save medication resource. Because the patients are willing to get healthcare knowledge to enhance the ability of self-care, they pay more attention to the health education. In Taiwan, the clinical nurses play an important role in patient education, and the health education take most time in their daily work. Such work includes the collection, production and delivery of education materials. To generate the correct and customized health education material is the key of success of patient education. In this study, we established a computer-aided health education contents generating system for psychiatric patients by integrating the databases for disease, medicine and nursing knowledge to assist nurse generating the customized health education document suitable for different patients. This system was evaluated by clinical nurses in usability and feasibility. This system is helpful for nurse to carry out the clinical health education to patients and further to encourage patient to pay attention to self-health.

  8. Computer-aided operations engineering with integrated models of systems and operations

    Science.gov (United States)

    Malin, Jane T.; Ryan, Dan; Fleming, Land

    1994-01-01

    CONFIG 3 is a prototype software tool that supports integrated conceptual design evaluation from early in the product life cycle, by supporting isolated or integrated modeling, simulation, and analysis of the function, structure, behavior, failures and operation of system designs. Integration and reuse of models is supported in an object-oriented environment providing capabilities for graph analysis and discrete event simulation. Integration is supported among diverse modeling approaches (component view, configuration or flow path view, and procedure view) and diverse simulation and analysis approaches. Support is provided for integrated engineering in diverse design domains, including mechanical and electro-mechanical systems, distributed computer systems, and chemical processing and transport systems. CONFIG supports abstracted qualitative and symbolic modeling, for early conceptual design. System models are component structure models with operating modes, with embedded time-related behavior models. CONFIG supports failure modeling and modeling of state or configuration changes that result in dynamic changes in dependencies among components. Operations and procedure models are activity structure models that interact with system models. CONFIG is designed to support evaluation of system operability, diagnosability and fault tolerance, and analysis of the development of system effects of problems over time, including faults, failures, and procedural or environmental difficulties.

  9. Computer Aided Product Service Systems Design : Service CAD and Its integration with Life Cycle Simulation

    NARCIS (Netherlands)

    Komoto, H.

    2009-01-01

    Integration of product design into service design, or vice versa, is considered to bring more efficient and effective value addition. Besides EcoDesign tools and methods, a methodology to design such an integration of products and services from a systemic perspective, or product-service systems

  10. Model-based Computer Aided Framework for Design of Process Monitoring and Analysis Systems

    DEFF Research Database (Denmark)

    Singh, Ravendra; Gernaey, Krist; Gani, Rafiqul

    2009-01-01

    In the manufacturing industry, for example, the pharmaceutical industry, a thorough understanding of the process is necessary in addition to a properly designed monitoring and analysis system (PAT system) to consistently obtain the desired end-product properties. A model-based computer....... The knowledge base provides the necessary information/data during the design of the PAT system while the model library generates additional or missing data needed for design and analysis. Optimization of the PAT system design is achieved in terms of product data analysis time and/or cost of monitoring equipment......-aided framework including the methods and tools through which the design of monitoring and analysis systems for product quality control can be generated, analyzed and/or validated, has been developed. Two important supporting tools developed as part of the framework are a knowledge base and a model library...

  11. Computer aided planning of distribution systems and connection with medium term load forecast

    Energy Technology Data Exchange (ETDEWEB)

    di Salvatore, F; Grattieri, W; Insinga, F; Malafarina, L; Mazzoni, M; Nicola, G

    1991-12-31

    In order to perform planning studies on HV (40-l50 kV), MV and LV networks, ENEL (Italian Electricity Board) has developed a computation system composed of a set of integrated programs which utilize the information stored in several data bases, with the aim of: providing energy consumption forecasts for each area of the country; transfering consumption for each area to the distribution network nodes and to evaluating the electric demand by using a statistical power/energy correlation model; analyzing several network development alternatives and selecting the optimum development plan by comparing the overall costs (investments, operation, risk). In order to make its utilization by planners easier, the computation system will be operated with interactive and graphic procedures made available by the use of graphic work stations. This report describes the main objectives and basic hypotheses assumed in the preparation of the computation system, as well as, the system`s general architecture.

  12. CASE/A - COMPUTER AIDED SYSTEM ENGINEERING AND ANALYSIS, ECLSS/ATCS SERIES

    Science.gov (United States)

    Bacskay, A.

    1994-01-01

    Design and analysis of Environmental Control and Life Support Systems (ECLSS) and Active Thermal Control Systems (ATCS) for spacecraft missions requires powerful software that is flexible and responsive to the demands of particular projects. CASE/A is an interactive trade study and analysis tool designed to increase productivity during all phases of systems engineering. The graphics-based command-driven package provides a user-friendly environment in which the engineer can analyze the performance and interface characteristics of an ECLS/ATC system. The package is useful during all phases of a spacecraft design program, from initial conceptual design trade studies to the actual flight, including pre-flight prediction and in-flight anomaly analysis. The CASE/A program consists of three fundamental parts: 1) the schematic management system, 2) the database management system, and 3) the simulation control and execution system. The schematic management system allows the user to graphically construct a system model by arranging icons representing system components and connecting the components with physical fluid streams. Version 4.1 contains 51 fully coded and documented default component routines. New components can be added by the user through the "blackbox" component option. The database management system supports the storage and manipulation of component data, output data, and solution control data through interactive edit screens. The simulation control and execution system initiates and controls the iterative solution process, displaying time status and any necessary diagnostic messages. In addition to these primary functions, the program provides three other important functional areas: 1) model output management, 2) system utility commands, and 3) user operations logic capacity. The model output management system provides tabular and graphical output capability. Complete fluid constituent mass fraction and properties data (mass flow, pressure, temperature

  13. Operator Station Design System - A computer aided design approach to work station layout

    Science.gov (United States)

    Lewis, J. L.

    1979-01-01

    The Operator Station Design System is resident in NASA's Johnson Space Center Spacecraft Design Division Performance Laboratory. It includes stand-alone minicomputer hardware and Panel Layout Automated Interactive Design and Crew Station Assessment of Reach software. The data base consists of the Shuttle Transportation System Orbiter Crew Compartment (in part), the Orbiter payload bay and remote manipulator (in part), and various anthropometric populations. The system is utilized to provide panel layouts, assess reach and vision, determine interference and fit problems early in the design phase, study design applications as a function of anthropometric and mission requirements, and to accomplish conceptual design to support advanced study efforts.

  14. Nodule detection by chest X-ray and evaluation of computer-aided detection (CAD) software using an originally developed phantom for instructional purposes

    International Nuclear Information System (INIS)

    Nitta, Norihisa; Takahashi, Masashi; Takazakura, Ryutaro

    2006-01-01

    Chest X-ray and computed tomography (CT) are indispensable modalities for lung cancer examinations. CT technologies have dramatically improved and small nodules and obscure shadows have been detected more frequently. The new generation of radiologists feels that chest X-rays are not as useful as chest CT. Experiments using a newly-developed chest phantom were conducted to reconfirm blind spots in chest X-rays. Recent technological advances and high-definition capability have made chest X-rays more useful than ever. Even though development of multi-detector CT (MDCT) has facilitated detection of nodules, it has conversely incurred a problem of increasing data for analysis, taking tremendous time and effort. Here, employing a chest phantom and clinical samples, we evaluated the utility of two kinds of computer-aided detection (CAD) software (Image Checker CT and LungCARE NEV) as well as GGO CAD software that we have developed. More development of chest CT diagnostic software is urgently needed. (author)

  15. Computer aided planning of distribution systems and connection with medium term load forecast

    International Nuclear Information System (INIS)

    di Salvatore, F.; Grattieri, W.; Insinga, F.; Malafarina, L.; Mazzoni, M.; Nicola, G.

    1990-01-01

    In order to perform planning studies on HV (40-l50 kV), MV and LV networks, ENEL (Italian Electricity Board) has developed a computation system composed of a set of integrated programs which utilize the information stored in several data bases, with the aim of: providing energy consumption forecasts for each area of the country; transferring consumption for each area to the distribution network nodes and to evaluating the electric demand by using a statistical power/energy correlation model; analyzing several network development alternatives and selecting the optimum development plan by comparing the overall costs (investments, operation, risk). In order to make its utilization by planners easier, the computation system will be operated with interactive and graphic procedures made available by the use of graphic work stations. This report describes the main objectives and basic hypotheses assumed in the preparation of the computation system, as well as, the system's general architecture

  16. Computer-Aided Design Methods for Model-Based Nonlinear Engine Control Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Traditional design methods for aircraft turbine engine control systems have relied on the use of linearized models and linear control theory. While these controllers...

  17. Computer aided periodical and regulated service tests on radiation measuring systems

    International Nuclear Information System (INIS)

    Sandner, W.; Lin, R.; Rothhaupt, W.

    1994-01-01

    Measuring systems for radioactive radiation, which must be registered by official order, have to be tested periodically according to laid down rules (WKP). A strategy for a test-device was drawn up for a flexible adaption of the procedure to individual requests, but also for a standardization of the logical interface to the measuring system. Especially the interaction of testing and normal measuring procedures is clearly defined and transparent; the original functional parts of the measuring run are used during the test as far as possible. Adapation to individual requirements is controlled by ASCII-Files, so that the program code remains unchanged. The functional possibilities are extensive also for the inspections by customers and authorities. Due to the nearly automatical run of the procedure, including printout of the results, the tests are always comparable. The standard was checked by some actual projects, basede on SYSTEM 7000 (Thermo Instrument Systems GmbH) and PC runing under DOS. (orig.) [de

  18. Computer aided design, analysis and experimental investigation of membrane assisted batch reaction-separation systems

    DEFF Research Database (Denmark)

    Mitkowski, Piotr Tomasz; Buchaly, Carsten; Kreis, Peter

    2009-01-01

    Membrane assisted batch reaction operation offers an interesting option for equilibrium limited reaction systems in chemical and biochemical manufacturing by selective removal of one of the products and thereby increasing the product yield. The design of such hybrid systems need to take into acco......Membrane assisted batch reaction operation offers an interesting option for equilibrium limited reaction systems in chemical and biochemical manufacturing by selective removal of one of the products and thereby increasing the product yield. The design of such hybrid systems need to take...... into account the performance of each constituent element and the optimisation of the design must take into consideration their interdependency. In this paper use of a membrane, to assist in the synthesis of propyl-propionate is investigated through the use of a hybrid process design framework, which consists...... and separation functionalities and to design/analyse the hybrid scheme. The generated hybrid scheme has been validated through experiments involving an esterification reaction....

  19. Computer-aided engineering system for design of sequence arrays and lithographic masks

    Science.gov (United States)

    Hubbell, Earl A.; Morris, MacDonald S.; Winkler, James L.

    1996-01-01

    An improved set of computer tools for forming arrays. According to one aspect of the invention, a computer system (100) is used to select probes and design the layout of an array of DNA or other polymers with certain beneficial characteristics. According to another aspect of the invention, a computer system uses chip design files (104) to design and/or generate lithographic masks (110).

  20. An Intelligent Computer-aided Training System (CAT) for Diagnosing Adult Illiterates: Integrating NASA Technology into Workplace Literacy

    Science.gov (United States)

    Yaden, David B., Jr.

    1991-01-01

    An important part of NASA's mission involves the secondary application of its technologies in the public and private sectors. One current application being developed is The Adult Literacy Evaluator, a simulation-based diagnostic tool designed to assess the operant literacy abilities of adults having difficulties in learning to read and write. Using Intelligent Computer-Aided Training (ICAT) system technology in addition to speech recognition, closed-captioned television (CCTV), live video and other state-of-the-art graphics and storage capabilities, this project attempts to overcome the negative effects of adult literacy assessment by allowing the client to interact with an intelligent computer system which simulates real-life literacy activities and materials and which measures literacy performance in the actual context of its use. The specific objectives of the project are as follows: (1) to develop a simulation-based diagnostic tool to assess adults' prior knowledge about reading and writing processes in actual contexts of application; (2) to provide a profile of readers' strengths and weaknesses; and (3) to suggest instructional strategies and materials which can be used as a beginning point for remediation. In the first and development phase of the project, descriptions of literacy events and environments are being written and functional literacy documents analyzed for their components. From these descriptions, scripts are being generated which define the interaction between the student, an on-screen guide and the simulated literacy environment.

  1. VPIsystems industry training program on computer-aided design of fiber optic communication systems

    Science.gov (United States)

    Richter, Andre; Chan, David K. C.

    2002-05-01

    In industry today, professional Photonic Design Automation (PDA) tools are a necessity to enable fast development cycles for the design of optical components, systems and networks. The training of industrial personnel is of great importance in facilitating the full usability of PDA tools tailored to meet these demands. As the market leader of design and planning tools for system integrators and manufacturers of optical transmission systems and components, VPIsystems offers a set of two-day training courses. Attendees are taught on the design of metro WDM networks, high speed DWDM and ultra long-haul WDM systems, analogue and digital cable access systems, EDFA and Raman amplifiers, as well as active devices and circuits. The course work compromises of: (1) lectures on physical and modeling background topics; (2) creation of typical simulation scenarios and; (3) the analysis of results. This course work is facilitated by guided, hands-on lab exercises using VPIsystems software for a variety of practical design situations. In classes of up to 15, each attendee is allocated a computer, thereby allowing for a thorough and speedy training for the individual in all of the covered topics as well as for any extra-curriculum topics to be covered. Since 1999, more than 750 people have graduated from over 60 training courses. In this paper, details of VPIsystems Industry training program will be presented.

  2. Computer aided analysis and design of industrial energy systems; Rechnergestuetzte Analyse und Konzeption industrieller Energiesysteme

    Energy Technology Data Exchange (ETDEWEB)

    Augenstein, Eckardt Marc Guenter

    2009-03-02

    In this dissertation the concept and implementation of a software system supporting the analysis and the design of industrial energy systems is presented. As a basis, a software framework was designed supplying a domain specific object model allowing the description of energy systems as well as the energy auditing projects performed with the software. Moreover, a set of graphical and textual editors needed to model the examined systems is part of the framework. On the other hand, the professional methods for analysis, assessment and optimization of energy systems are implemented in modules integrated into the system via a plug-in interface. The object model whose definition was based on a meta model approach allows the description of network like structures typical to energy systems. In order to keep track of the different work steps performed during an analysis project, these steps are reflected in the object model as ''method applications'' using a tree as the basic structure of a project. In order to allow the compatibility of information a set of conventions for the evaluation of energy flows and system balances was introduced. Moreover, all data elements used in modules or model components are derived from a central database guaranteeing a consistent usage of terms, descriptions, validity ranges and data types. The single professional modules like simulators or optimization methods access the object model via an appropriate software interface. Moreover, they make use of the framework's user interface engine by delivering a generic description of dialog screens and result reports. As all modules share the same set of objects modelling the components of the energy system surveyed, the flow of information from module to module can be designed virtually seamless. Compared to a number of stand-alone solutions, this integrated design approach has the advantage that by combining a set of specialized methods an overall solution for complex

  3. Computer Aided Design of The Cooling System for Plastic Injection Molds

    Directory of Open Access Journals (Sweden)

    Hakan GÜRÜN

    2009-02-01

    Full Text Available The design of plastic injection molds and their cooling systems affect both the dimension, the shape, the quality of a plastic part and the cycle time of process and the cost of mold. In this study, the solid model design of a plastic injection mold and the design of cooling sysytem were possibly carried out without the designer interaction. Developed program permited the use of three types of the cooling system and the different cavity orientations and the multible plastic part placement into the mold cores. The program which was developed by using Visual LISP language and the VBA (Visual BASIC for Application modules, was applicated in the AutoCAD software domain. Trial studies were presented that the solid model design of plastic injection molds and the cooling systems increased the reliability, the flexibility and the speed of the design.

  4. Virtual environment and computer-aided technologies used for system prototyping and requirements development

    Science.gov (United States)

    Logan, Cory; Maida, James; Goldsby, Michael; Clark, Jim; Wu, Liew; Prenger, Henk

    1993-01-01

    The Space Station Freedom (SSF) Data Management System (DMS) consists of distributed hardware and software which monitor and control the many onboard systems. Virtual environment and off-the-shelf computer technologies can be used at critical points in project development to aid in objectives and requirements development. Geometric models (images) coupled with off-the-shelf hardware and software technologies were used in The Space Station Mockup and Trainer Facility (SSMTF) Crew Operational Assessment Project. Rapid prototyping is shown to be a valuable tool for operational procedure and system hardware and software requirements development. The project objectives, hardware and software technologies used, data gained, current activities, future development and training objectives shall be discussed. The importance of defining prototyping objectives and staying focused while maintaining schedules are discussed along with project pitfalls.

  5. Computer-Aided Authoring System (AUTHOR) User's Guide. Volume I. Final Report.

    Science.gov (United States)

    Guitard, Charles R.

    This user's guide for AUTHOR, an automatic authoring system which produces programmed texts for teaching symbol recognition, provides detailed instructions to help the user construct and enter the information needed to create the programmed text, run the AUTHOR program, and edit the automatically composed paper. Major sections describe steps in…

  6. Computer-Aided Systems Engineering for Flight Research Projects Using a Workgroup Database

    Science.gov (United States)

    Mizukami, Masahi

    2004-01-01

    An online systems engineering tool for flight research projects has been developed through the use of a workgroup database. Capabilities are implemented for typical flight research systems engineering needs in document library, configuration control, hazard analysis, hardware database, requirements management, action item tracking, project team information, and technical performance metrics. Repetitive tasks are automated to reduce workload and errors. Current data and documents are instantly available online and can be worked on collaboratively. Existing forms and conventional processes are used, rather than inventing or changing processes to fit the tool. An integrated tool set offers advantages by automatically cross-referencing data, minimizing redundant data entry, and reducing the number of programs that must be learned. With a simplified approach, significant improvements are attained over existing capabilities for minimal cost. By using a workgroup-level database platform, personnel most directly involved in the project can develop, modify, and maintain the system, thereby saving time and money. As a pilot project, the system has been used to support an in-house flight experiment. Options are proposed for developing and deploying this type of tool on a more extensive basis.

  7. Southwell's Relaxation Search in Computer Aided Advising: An Intelligent Information System.

    Science.gov (United States)

    Song, Xueshu

    1992-01-01

    Describes the development and validation of a microcomputer software system that enhances undergraduate students' interests in becoming engineering graduate students. The development of a database with information on engineering graduate programs is discussed, and a model that matches individual and institutional needs using Southwell's Relaxation…

  8. Engineering constraints and computer-aided optimization of electrostatic lens systems

    International Nuclear Information System (INIS)

    Steen, H.W.G. van der; Barth, J.E.; Adriaanse, J.P.

    1990-01-01

    An optimization tool for the design of electrostatic lens systems with axial symmetry is presented. This tool is based on the second-order electrode method combined with a multivariable numerical optimization procedure. The second-order electrode method makes a cubic spline approximation to the axial potential for a given electrode shape. With the help of this approximation, a numerical optimization can be done. To demonstrate this optimization tool, a lens system for Auger analyses is optimized. It is shown that variations in the practical constraints imposed on the design, like maximum electrode potential or maximum lens diameter, have strong effects on the obtainable lens quality. It is concluded that a numerical optimization does not take over the lens designer's job, but allows him to thoroughly examine the optical consequences of engineering choices by finding the optimum design for each set of constraints. (orig.)

  9. A computer-aided control system for automatic performance measurements on the LHC series dipoles

    International Nuclear Information System (INIS)

    Gorskaya, E.; Samojlov, V.; Raimondo, A.; Rijllart, A.

    2003-01-01

    The control system software (Test Master) for the Large Hadron Collider (LHC) magnet series measurements is presented. This system was developed at CERN to automate as many tests on the LHC magnets as possible. The Test Master software is the middle layer of the main software architecture developed by the LHC/IAS group for central supervision of all types of LHC dipole tests in the SM18 hall. It serves as a manager and scheduler for applications, controlling all measurements that are performed in a cluster of two test benches. The software was implemented in the LabVIEW environment. The information about the interactive user interface, the software architecture, communication protocols, file-configuration different types of commands and status files of the Test Master are described

  10. Design, development and commercialization of ISOCAD (Integrated System of Computer Aided Dosimetry) for gamma irradiators

    International Nuclear Information System (INIS)

    Shrivastava, Amit; Srivastava, Navneet; Kohli, A.K.; Mishra, Vinay Kumar; Singh, Ramnik; Sinha, A.K.

    2014-01-01

    ISOMED facility is the indomitable architect of radiation sterilization era in the country providing the contract radiation processing services for the terminal sterilization of the healthcare products from the healthcare sector. ISOMED has acquired the international standards viz.ISO 9001, ISO 22000, ISO 13485, ISO 11137, OHSAS 18001, ISO 14001 that supplemented by European Union - GMP certification from MHRA - UK. One of the core focuses of these standards is the control of measuring and monitoring instruments with impeccable traceability features with respect to the quality critical processing data. The gamma radiation sterilisation process involves delivery of minimum 25 kGy of radiation dose to the healthcare products which is measured by internationally acclaimed Cerric Cerric Potentiometric Dose Measurement Systems (CCPDMs). As the current variant of this system had extensive involvement of manual interventions, a novel, bar code based computerized application package called ISOCAD, incorporating portable risk free snapping tool for the dosimeter ampules has been synergistically developed by BRIT/BARC for the Cerric Cerrous Potentiometric Dose Measurement System for Gamma Irradiators. ISOCAD has been successfully operating in ISOMED and the techno commercial viability has been convincingly demonstrated to the operators of the gamma irradiators from the country as well as abroad. ISOCAD is now available as one of the commercial product packages from BRIT. (author)

  11. Study on computer-aided control system design platform of 10MW high temperature gas-cooled test reactor

    International Nuclear Information System (INIS)

    Feng Yan; Shi Lei; Sun Yuliang; Luo Shaojie

    2004-01-01

    the 10 MW high temperature gas-cooled test reactor (HTR-10) is the first modular pebble bed reactor built in China, which needs to be researched on engineering design, control study, safety analysis and operator training. An integrated system for simulation, control design and online assistance of the HTR-10 (HTRSIMU) has been developed by the Institute of Nuclear Energy Technology (INET) of Tsinghua University. The HTRSIMU system is based on a high-speed local area network, on which a computer-aided control system design platform (CDP) is developed and combined with the simulating subsystem in order to provide a visualized and convenient tool for the HTR-10 control system design. The CDP has friendly man-machine interface and good expansibility, in which eighteen types of control items are integrated. These control items are divided into two types: linear and non-linear control items. The linear control items include Proportion, Integral, Differential, Inertial, Leed-lag, Oscillation, Pure-lag, Common, PID and Fuzzy, while the non-linear control items include Saturation, Subsection, Insensitive, Backlash, Relay, Insensi-Relay, Sluggish-Relay and Insens-Slug. The CDP provides a visualized platform for control system modeling and the control loop system can be automatically generated and graphically simulated. Users can conveniently design control loop, modify control parameters, study control method, and analyze control results just by clicking mouse buttons. This kind of control system design method can provide a powerful tool and good reference for the actual system operation for HTR-10. A control scheme is also given and studied to demonstrate the functions of the CDP in this article. (author)

  12. An Open Source Rapid Computer Aided Control System Design Toolchain Using Scilab, Scicos and RTAI Linux

    Science.gov (United States)

    Bouchpan-Lerust-Juéry, L.

    2007-08-01

    Current and next generation on-board computer systems tend to implement real-time embedded control applications (e.g. Attitude and Orbit Control Subsystem (AOCS), Packet Utililization Standard (PUS), spacecraft autonomy . . . ) which must meet high standards of Reliability and Predictability as well as Safety. All these requirements require a considerable amount of effort and cost for Space Sofware Industry. This paper, in a first part, presents a free Open Source integrated solution to develop RTAI applications from analysis, design, simulation and direct implementation using code generation based on Open Source and in its second part summarises this suggested approach, its results and the conclusion for further work.

  13. A Computer-Aided Bibliometrics System for Journal Citation Analysis and Departmental Core Journal Ranking List Generation

    Directory of Open Access Journals (Sweden)

    Yih-Chearng Shiue

    2004-12-01

    Full Text Available Due to the tremendous increase and variation in serial publications, faculties in department of university are finding it difficult to generate and update their departmental core journal list regularly and accurately, and libraries are finding it difficult to maintain their current serial collection for different departments. Therefore, the evaluation of a departmental core journal list is an important task for departmental faculties and librarians. A departmental core journal list not only helps departments understand research performances of faculties and students, but also helps librarians make decisions about which journals to retain and which to cancel. In this study, a Computer-Aided Bibliometrics System was implemented and two methodologies (JCDF and LibJF were proposed in order to generate a departmental core journal ranking list and make the journal citation analysis. Six departments were taken as examples, with MIS as the major one. One journal citation pattern was found and the ratio of Turning point-to-No. journal was always around 0.07 among the 10 journals and 6 departments. After comparing with four methodologies via overlapping rate and standard deviation distances, the two proposed methodologies were shown to be better than questionnaire and library subscription method.

  14. Computer aided diagnosis system for Alzheimer disease using brain diffusion tensor imaging features selected by Pearson's correlation.

    Science.gov (United States)

    Graña, M; Termenon, M; Savio, A; Gonzalez-Pinto, A; Echeveste, J; Pérez, J M; Besga, A

    2011-09-20

    The aim of this paper is to obtain discriminant features from two scalar measures of Diffusion Tensor Imaging (DTI) data, Fractional Anisotropy (FA) and Mean Diffusivity (MD), and to train and test classifiers able to discriminate Alzheimer's Disease (AD) patients from controls on the basis of features extracted from the FA or MD volumes. In this study, support vector machine (SVM) classifier was trained and tested on FA and MD data. Feature selection is done computing the Pearson's correlation between FA or MD values at voxel site across subjects and the indicative variable specifying the subject class. Voxel sites with high absolute correlation are selected for feature extraction. Results are obtained over an on-going study in Hospital de Santiago Apostol collecting anatomical T1-weighted MRI volumes and DTI data from healthy control subjects and AD patients. FA features and a linear SVM classifier achieve perfect accuracy, sensitivity and specificity in several cross-validation studies, supporting the usefulness of DTI-derived features as an image-marker for AD and to the feasibility of building Computer Aided Diagnosis systems for AD based on them. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  15. Computed aided system for separation and classification of the abnormal erythrocytes in human blood

    Science.gov (United States)

    Wąsowicz, Michał; Grochowski, Michał; Kulka, Marek; Mikołajczyk, Agnieszka; Ficek, Mateusz; Karpieńko, Katarzyna; Cićkiewicz, Maciej

    2017-12-01

    The human peripheral blood consists of cells (red cells, white cells, and platelets) suspended in plasma. In the following research the team assessed an influence of nanodiamond particles on blood elements over various periods of time. The material used in the study consisted of samples taken from ten healthy humans of various age, different blood types and both sexes. The markings were leaded by adding to the blood unmodified diamonds and oxidation modified. The blood was put under an impact of two diamond concentrations: 20μl and 100μl. The amount of abnormal cells increased with time. The percentage of echinocytes as a result of interaction with nanodiamonds in various time intervals for individual specimens was scarce. The impact of the two diamond types had no clinical importance on red blood cells. It is supposed that as a result of longlasting exposure a dehydratation of red cells takes place, because of the function of the cells. The analysis of an influence of nanodiamond particles on blood elements was supported by computer system designed for automatic counting and classification of the Red Blood Cells (RBC). The system utilizes advanced image processing methods for RBCs separation and counting and Eigenfaces method coupled with the neural networks for RBCs classification into normal and abnormal cells purposes.

  16. PERANCANGAN COMPUTER AIDED SYSTEM DALAM MENGANALISA HUMAN ERROR DI PERKERETAAPIAN INDONESIA

    Directory of Open Access Journals (Sweden)

    Wiwik Budiawan

    2013-06-01

    Full Text Available Kecelakaan kereta api (KA yang terjadi secara beruntun di Indonesia sudah berada pada tingkat kritis. Berdasarkan data dari Direktorat Jendral Perkeretaapian, dalam kurun 5 tahun terakhir (2005-2009 total terdapat 611 kecelakaan KA.  Banyak faktor yang berkontribusi menyebabkan terjadinya kecelakaan, antara lain: sarana, prasarana, SDM operator (human error, eksternal, dan alam.  Kegagalan manusia (Human error merupakan salah satu faktor yang berpotensi menyebabkan terjadinya suatu kecelakaan KA dan dinyatakan sebagai faktor utama penyebab terjadinya suatu kecelakaan kereta api di Indonesia. Namun, tidak jelas bagaimana teknik analisis ini dilakukan. Kajian human error yang dilakukan Komite Nasional Keselamatan Transportasi (KNKT masih relatif terbatas, tidak dilengkapi dengan metode yang sistematis. Terdapat beberapa metode yang telah dikembangkan saat ini, tetapi untuk moda transportasi kereta api masih belum banyak dikembangkan. Human Factors Analysis and Classification System (HFACS merupakan metode analisis human error yang dikembangkan dan disesuaikan dengan sistem perkeretaapian Indonesia. Guna meningkatkan keandalan dalam analisis human error, HFACS kemudian dikembangkan dalam bentuk aplikasi berbasis web yang dapat diakses di komputer maupun smartphone. Hasil penelitian ini dapat dimanfaatkan oleh KNKT sebagai metode analisis kecelakaan kereta api khususnya terkait dengan human error. Kata kunci : human error, HFACS, CAS, kereta api   Abstract Train wreck (KA which occurred in quick succession in Indonesia already at a critical level. Based on data from the Directorate General of Railways, during the last 5 years (2005-2009 there were a total of 611 railway accidents. Many factors contribute to cause accidents, such as: facilities, infrastructure, human operator (human error, external, and natural. Human failure (Human error is one of the factors that could potentially cause a train accident and expressed as the main factors causing

  17. An application of computer aided requirements analysis to a real time deep space system

    Science.gov (United States)

    Farny, A. M.; Morris, R. V.; Hartsough, C.; Callender, E. D.; Teichroew, D.; Chikofsky, E.

    1981-01-01

    The entire procedure of incorporating the requirements and goals of a space flight project into integrated, time ordered sequences of spacecraft commands, is called the uplink process. The Uplink Process Control Task (UPCT) was created to examine the uplink process and determine ways to improve it. The Problem Statement Language/Problem Statement Analyzer (PSL/PSA) designed to assist the designer/analyst/engineer in the preparation of specifications of an information system is used as a supporting tool to aid in the analysis. Attention is given to a definition of the uplink process, the definition of PSL/PSA, the construction of a PSA database, the value of analysis to the study of the uplink process, and the PSL/PSA lessons learned.

  18. Computer aided product design

    DEFF Research Database (Denmark)

    Constantinou, Leonidas; Bagherpour, Khosrow; Gani, Rafiqul

    1996-01-01

    A general methodology for Computer Aided Product Design (CAPD) with specified property constraints which is capable of solving a large range of problems is presented. The methodology employs the group contribution approach, generates acyclic, cyclic and aromatic compounds of various degrees......-liquid equilibria (LLE), solid-liquid equilibria (SLE) and gas solubility. Finally, a computer program based on the extended methodology has been developed and the results from five case studies highlighting various features of the methodology are presented....

  19. Computer aided design for the nuclear industry

    International Nuclear Information System (INIS)

    Basson, Keith

    1986-01-01

    The paper concerns the new computer aided design (CAD) centre for the United Kingdom nuclear industry, and its applications. A description of the CAD system is given, including the current projects at the CAD centre. Typical applications of the 3D CAD plant based models, stress analysis studies, and the extraction of data from CAD drawings to produce associated documentation, are all described. Future developments using computer aided design systems are also considered. (U.K.)

  20. Computer-aided design system for a complex of problems on calculation and analysis of engineering and economical indexes of NPP power units

    International Nuclear Information System (INIS)

    Stepanov, V.I.; Koryagin, A.V.; Ruzankov, V.N.

    1988-01-01

    Computer-aided design system for a complex of problems concerning calculation and analysis of engineering and economical indices of NPP power units is described. In the system there are means for automated preparation and debugging of data base software complex, which realizes th plotted algorithm in the power unit control system. Besides, in the system there are devices for automated preparation and registration of technical documentation

  1. SPLPKG WFCMPR WFAPPX, Wilson-Fowler Spline Generator for Computer Aided Design And Manufacturing (CAD/CAM) Systems

    International Nuclear Information System (INIS)

    Fletcher, S.K.

    2002-01-01

    1 - Description of program or function: The three programs SPLPKG, WFCMPR, and WFAPPX provide the capability for interactively generating, comparing and approximating Wilson-Fowler Splines. The Wilson-Fowler spline is widely used in Computer Aided Design and Manufacturing (CAD/CAM) systems. It is favored for many applications because it produces a smooth, low curvature fit to planar data points. Program SPLPKG generates a Wilson-Fowler spline passing through given nodes (with given end conditions) and also generates a piecewise linear approximation to that spline within a user-defined tolerance. The program may be used to generate a 'desired' spline against which to compare other Splines generated by CAD/CAM systems. It may also be used to generate an acceptable approximation to a desired spline in the event that an acceptable spline cannot be generated by the receiving CAD/CAM system. SPLPKG writes an IGES file of points evaluated on the spline and/or a file containing the spline description. Program WFCMPR computes the maximum difference between two Wilson-Fowler Splines and may be used to verify the spline recomputed by a receiving system. It compares two Wilson-Fowler Splines with common nodes and reports the maximum distance between curves (measured perpendicular to segments) and the maximum difference of their tangents (or normals), both computed along the entire length of the Splines. Program WFAPPX computes the maximum difference between a Wilson- Fowler spline and a piecewise linear curve. It may be used to accept or reject a proposed approximation to a desired Wilson-Fowler spline, even if the origin of the approximation is unknown. The maximum deviation between these two curves, and the parameter value on the spline where it occurs are reported. 2 - Restrictions on the complexity of the problem - Maxima of: 1600 evaluation points (SPLPKG), 1000 evaluation points (WFAPPX), 1000 linear curve breakpoints (WFAPPX), 100 spline Nodes

  2. A new computer aided diagnosis system for evaluation of chronic liver disease with ultrasound shear wave elastography imaging.

    Science.gov (United States)

    Gatos, Ilias; Tsantis, Stavros; Spiliopoulos, Stavros; Karnabatidis, Dimitris; Theotokas, Ioannis; Zoumpoulis, Pavlos; Loupas, Thanasis; Hazle, John D; Kagadis, George C

    2016-03-01

    Classify chronic liver disease (CLD) from ultrasound shear-wave elastography (SWE) imaging by means of a computer aided diagnosis (CAD) system. The proposed algorithm employs an inverse mapping technique (red-green-blue to stiffness) to quantify 85 SWE images (54 healthy and 31 with CLD). Texture analysis is then applied involving the automatic calculation of 330 first and second order textural features from every transformed stiffness value map to determine functional features that characterize liver elasticity and describe liver condition for all available stages. Consequently, a stepwise regression analysis feature selection procedure is utilized toward a reduced feature subset that is fed into the support vector machines (SVMs) classification algorithm in the design of the CAD system. With regard to the mapping procedure accuracy, the stiffness map values had an average difference of 0.01 ± 0.001 kPa compared to the quantification results derived from the color-box provided by the built-in software of the ultrasound system. Highest classification accuracy from the SVM model was 87.0% with sensitivity and specificity values of 83.3% and 89.1%, respectively. Receiver operating characteristic curves analysis gave an area under the curve value of 0.85 with [0.77-0.89] confidence interval. The proposed CAD system employing color to stiffness mapping and classification algorithms offered superior results, comparing the already published clinical studies. It could prove to be of value to physicians improving the diagnostic accuracy of CLD and can be employed as a second opinion tool for avoiding unnecessary invasive procedures.

  3. Performance of computer-aided detection of pulmonary nodules in low-dose CT: comparison with double reading by nodule volume

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yingru; Vliegenthart, Rozemarijn; Wang, Ying; Ooijen, Peter M.A. van; Oudkerk, Matthijs [University of Groningen/University Medical Center Groningen, Center for Medical Imaging - North East Netherlands, Department of Radiology, P.O. Box 30.001, Groningen (Netherlands); Bock, Geertruida H. de [University of Groningen/University Medical Center Groningen, Department of Epidemiology, P.O. Box 30.001, Groningen (Netherlands); Klaveren, Rob J. van [Lievensberg Hospital, Department of Pulmonology, P.O. Box 135, Bergen op Zoom (Netherlands); Bogoni, Luca [CAD Group, Siemens Medical Solutions USA, Inc., Malvern, PA (United States); Jong, Pim A. de; Mali, Willem P. [University of Utrecht, Department of Radiology, University Medical Center Utrecht, P.O. Box 85500, Utrecht (Netherlands)

    2012-10-15

    To evaluate performance of computer-aided detection (CAD) beyond double reading for pulmonary nodules on low-dose computed tomography (CT) by nodule volume. A total of 400 low-dose chest CT examinations were randomly selected from the NELSON lung cancer screening trial. CTs were evaluated by two independent readers and processed by CAD. A total of 1,667 findings marked by readers and/or CAD were evaluated by a consensus panel of expert chest radiologists. Performance was evaluated by calculating sensitivity of pulmonary nodule detection and number of false positives, by nodule characteristics and volume. According to the screening protocol, 90.9 % of the findings could be excluded from further evaluation, 49.2 % being small nodules (less than 50 mm{sup 3}). Excluding small nodules reduced false-positive detections by CAD from 3.7 to 1.9 per examination. Of 151 findings that needed further evaluation, 33 (21.9 %) were detected by CAD only, one of them being diagnosed as lung cancer the following year. The sensitivity of nodule detection was 78.1 % for double reading and 96.7 % for CAD. A total of 69.7 % of nodules undetected by readers were attached nodules of which 78.3 % were vessel-attached. CAD is valuable in lung cancer screening to improve sensitivity of pulmonary nodule detection beyond double reading, at a low false-positive rate when excluding small nodules. circle Computer-aided detection (CAD) has known advantages for computed tomography (CT). (orig.)

  4. Performance of computer-aided detection of pulmonary nodules in low-dose CT: comparison with double reading by nodule volume

    International Nuclear Information System (INIS)

    Zhao, Yingru; Vliegenthart, Rozemarijn; Wang, Ying; Ooijen, Peter M.A. van; Oudkerk, Matthijs; Bock, Geertruida H. de; Klaveren, Rob J. van; Bogoni, Luca; Jong, Pim A. de; Mali, Willem P.

    2012-01-01

    To evaluate performance of computer-aided detection (CAD) beyond double reading for pulmonary nodules on low-dose computed tomography (CT) by nodule volume. A total of 400 low-dose chest CT examinations were randomly selected from the NELSON lung cancer screening trial. CTs were evaluated by two independent readers and processed by CAD. A total of 1,667 findings marked by readers and/or CAD were evaluated by a consensus panel of expert chest radiologists. Performance was evaluated by calculating sensitivity of pulmonary nodule detection and number of false positives, by nodule characteristics and volume. According to the screening protocol, 90.9 % of the findings could be excluded from further evaluation, 49.2 % being small nodules (less than 50 mm 3 ). Excluding small nodules reduced false-positive detections by CAD from 3.7 to 1.9 per examination. Of 151 findings that needed further evaluation, 33 (21.9 %) were detected by CAD only, one of them being diagnosed as lung cancer the following year. The sensitivity of nodule detection was 78.1 % for double reading and 96.7 % for CAD. A total of 69.7 % of nodules undetected by readers were attached nodules of which 78.3 % were vessel-attached. CAD is valuable in lung cancer screening to improve sensitivity of pulmonary nodule detection beyond double reading, at a low false-positive rate when excluding small nodules. circle Computer-aided detection (CAD) has known advantages for computed tomography (CT). (orig.)

  5. Computer-aided system of evaluation for population-based all-in-one service screening (CASE-PASS): from study design to outcome analysis with bias adjustment.

    Science.gov (United States)

    Chen, Li-Sheng; Yen, Amy Ming-Fang; Duffy, Stephen W; Tabar, Laszlo; Lin, Wen-Chou; Chen, Hsiu-Hsi

    2010-10-01

    Population-based routine service screening has gained popularity following an era of randomized controlled trials. The evaluation of these service screening programs is subject to study design, data availability, and the precise data analysis for adjusting bias. We developed a computer-aided system that allows the evaluation of population-based service screening to unify these aspects and facilitate and guide the program assessor to efficiently perform an evaluation. This system underpins two experimental designs: the posttest-only non-equivalent design and the one-group pretest-posttest design and demonstrates the type of data required at both the population and individual levels. Three major analyses were developed that included a cumulative mortality analysis, survival analysis with lead-time adjustment, and self-selection bias adjustment. We used SAS AF software to develop a graphic interface system with a pull-down menu style. We demonstrate the application of this system with data obtained from a Swedish population-based service screen and a population-based randomized controlled trial for the screening of breast, colorectal, and prostate cancer, and one service screening program for cervical cancer with Pap smears. The system provided automated descriptive results based on the various sources of available data and cumulative mortality curves corresponding to the study designs. The comparison of cumulative survival between clinically and screen-detected cases without a lead-time adjustment are also demonstrated. The intention-to-treat and noncompliance analysis with self-selection bias adjustments are also shown to assess the effectiveness of the population-based service screening program. Model validation was composed of a comparison between our adjusted self-selection bias estimates and the empirical results on effectiveness reported in the literature. We demonstrate a computer-aided system allowing the evaluation of population-based service screening

  6. Role of Computer Aided Diagnosis (CAD) in the detection of pulmonary nodules on 64 row multi detector computed tomography.

    Science.gov (United States)

    Prakashini, K; Babu, Satish; Rajgopal, K V; Kokila, K Raja

    2016-01-01

    To determine the overall performance of an existing CAD algorithm with thin-section computed tomography (CT) in the detection of pulmonary nodules and to evaluate detection sensitivity at a varying range of nodule density, size, and location. A cross-sectional prospective study was conducted on 20 patients with 322 suspected nodules who underwent diagnostic chest imaging using 64-row multi-detector CT. The examinations were evaluated on reconstructed images of 1.4 mm thickness and 0.7 mm interval. Detection of pulmonary nodules, initially by a radiologist of 2 years experience (RAD) and later by CAD lung nodule software was assessed. Then, CAD nodule candidates were accepted or rejected accordingly. Detected nodules were classified based on their size, density, and location. The performance of the RAD and CAD system was compared with the gold standard that is true nodules confirmed by consensus of senior RAD and CAD together. The overall sensitivity and false-positive (FP) rate of CAD software was calculated. Of the 322 suspected nodules, 221 were classified as true nodules on the consensus of senior RAD and CAD together. Of the true nodules, the RAD detected 206 (93.2%) and 202 (91.4%) by the CAD. CAD and RAD together picked up more number of nodules than either CAD or RAD alone. Overall sensitivity for nodule detection with the CAD program was 91.4%, and FP detection per patient was 5.5%. The CAD showed comparatively higher sensitivity for nodules of size 4-10 mm (93.4%) and nodules in hilar (100%) and central (96.5%) location when compared to RAD's performance. CAD performance was high in detecting pulmonary nodules including the small size and low-density nodules. CAD even with relatively high FP rate, assists and improves RAD's performance as a second reader, especially for nodules located in the central and hilar region and for small nodules by saving RADs time.

  7. Evaluation of alveolar bone grafting in unilateral cleft lip and palate patients using a computer-aided diagnosis system

    International Nuclear Information System (INIS)

    Sutthiprapaporn, Pipop; Kongsomboon, Supaporn; Limmonthol, Saowaluck; Pisek, Poonsak; Keinprasit, Chutimaporn; Tanimoto, Keiji; Nakamoto, Takashi

    2012-01-01

    This study aimed to evaluate the trabecular bone changes after alveolar bone grafting in unilateral cleft lip and palate (UCLP) patients using a computer-aided diagnosis (CAD) system. The occlusal radiographs taken from 50 UCLP patients were surveyed retrospectively. The images were categorized as: 50 images in group 0 (before bone grafting), 33 images in group 1 (one month after bone grafting), 24 images in group 2 (2-4 months after bone grafting), 15 images in group 3 (5-7 months after bone grafting), and 21 images in group 4 (8 or more months after bone grafting). Each image was grouped as either 'non-cleft side' or 'cleft side'. The CAD system was used five times for each side to calculate the pixel area based on the mathematical morphology. Significant differences were found using a Wilcoxon signed ranks test or paired samples t test. The pixel area showed a significant difference between the 'non-cleft side' and 'cleft side' in group 0 (404.27±103.72/117.73±92.25; p=0.00), group 1 (434.29±86.70/388.31±109.51; p=0.01), and group 4 (430.98±98.11/366.71±154.59; p=0.02). No significant differences were found in group 2 (423.57±98.12/383.47±135.88; p=0.06) or group 3 (433.02±116.07/384.16±146.55; p=0.19). Based on the design of this study, alveolar bone grafting was similar to normal bone within 2-7 months postoperatively.

  8. Evaluation of alveolar bone grafting in unilateral cleft lip and palate patients using a computer-aided diagnosis system

    Energy Technology Data Exchange (ETDEWEB)

    Sutthiprapaporn, Pipop; Kongsomboon, Supaporn; Limmonthol, Saowaluck; Pisek, Poonsak; Keinprasit, Chutimaporn [Khon Kaen University, Khon Kaen (Thailand); Tanimoto, Keiji; Nakamoto, Takashi [Dept. of Oral and Maxillofacial Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima (Japan)

    2012-09-15

    This study aimed to evaluate the trabecular bone changes after alveolar bone grafting in unilateral cleft lip and palate (UCLP) patients using a computer-aided diagnosis (CAD) system. The occlusal radiographs taken from 50 UCLP patients were surveyed retrospectively. The images were categorized as: 50 images in group 0 (before bone grafting), 33 images in group 1 (one month after bone grafting), 24 images in group 2 (2-4 months after bone grafting), 15 images in group 3 (5-7 months after bone grafting), and 21 images in group 4 (8 or more months after bone grafting). Each image was grouped as either 'non-cleft side' or 'cleft side'. The CAD system was used five times for each side to calculate the pixel area based on the mathematical morphology. Significant differences were found using a Wilcoxon signed ranks test or paired samples t test. The pixel area showed a significant difference between the 'non-cleft side' and 'cleft side' in group 0 (404.27{+-}103.72/117.73{+-}92.25; p=0.00), group 1 (434.29{+-}86.70/388.31{+-}109.51; p=0.01), and group 4 (430.98{+-}98.11/366.71{+-}154.59; p=0.02). No significant differences were found in group 2 (423.57{+-}98.12/383.47{+-}135.88; p=0.06) or group 3 (433.02{+-}116.07/384.16{+-}146.55; p=0.19). Based on the design of this study, alveolar bone grafting was similar to normal bone within 2-7 months postoperatively.

  9. Evaluation of a Computer-aided Lung Auscultation System for Diagnosis of Bovine Respiratory Disease in Feedlot Cattle.

    Science.gov (United States)

    Mang, A V; Buczinski, S; Booker, C W; Timsit, E

    2015-01-01

    A computer-aided lung auscultation (CALA) system was recently developed to diagnose bovine respiratory disease (BRD) in feedlot cattle. To determine, in a case-control study, the level of agreement between CALA and veterinary lung auscultation and to evaluate the sensitivity (Se) and specificity (Sp) of CALA to diagnose BRD in feedlot cattle. A total of 561 Angus cross-steers (initial body weight = 246 ± 45 kg) were observed during the first 50 day after entry to a feedlot. Case-control study. Steers with visual signs of BRD identified by pen checkers were examined by a veterinarian, including lung auscultation using a conventional stethoscope and CALA that produced a lung score from 1 (normal) to 5 (chronic). For each steer examined for BRD, 1 apparently healthy steer was selected as control and similarly examined. Agreement between CALA and veterinary auscultation was assessed by kappa statistic. CALA's Se and Sp were estimated using Bayesian latent class analysis. Of the 561 steers, 35 were identified with visual signs of BRD and 35 were selected as controls. Comparison of veterinary auscultation and CALA (using a CALA score ≥2 as a cut off) revealed a substantial agreement (kappa = 0.77). Using latent class analysis, CALA had a relatively high Se (92.9%; 95% credible interval [CI] = 0.71-0.99) and Sp (89.6%; 95% CI = 0.64-0.99) for diagnosing BRD compared with pen checking. CALA had good diagnostic accuracy (albeit with a relatively wide CI). Its use in feedlots could increase the proportion of cattle accurately diagnosed with BRD. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  10. Computer-aided detection of lung nodules via 3D fast radial transform, scale space representation, and Zernike MIP classification.

    Science.gov (United States)

    Riccardi, Alessandro; Petkov, Todor Sergueev; Ferri, Gianluca; Masotti, Matteo; Campanini, Renato

    2011-04-01

    The authors presented a novel system for automated nodule detection in lung CT exams. The approach is based on (1) a lung tissue segmentation preprocessing step, composed of histogram thresholding, seeded region growing, and mathematical morphology; (2) a filtering step, whose aim is the preliminary detection of candidate nodules (via 3D fast radial filtering) and estimation of their geometrical features (via scale space analysis); and (3) a false positive reduction (FPR) step, comprising a heuristic FPR, which applies thresholds based on geometrical features, and a supervised FPR, which is based on support vector machines classification, which in turn, is enhanced by a feature extraction algorithm based on maximum intensity projection processing and Zernike moments. The system was validated on 154 chest axial CT exams provided by the lung image database consortium public database. The authors obtained correct detection of 71% of nodules marked by all radiologists, with a false positive rate of 6.5 false positives per patient (FP/patient). A higher specificity of 2.5 FP/patient was reached with a sensitivity of 60%. An independent test on the ANODE09 competition database obtained an overall score of 0.310. The system shows a novel approach to the problem of lung nodule detection in CT scans: It relies on filtering techniques, image transforms, and descriptors rather than region growing and nodule segmentation, and the results are comparable to those of other recent systems in literature and show little dependency on the different types of nodules, which is a good sign of robustness.

  11. Using Computer-Aided Software Engineering (CASE)--tools to document the current logical model of a system for DoD requirements specifications.

    OpenAIRE

    Ganzer, Donna A.

    1987-01-01

    Approved for public release; distribution is unlimited The Naval Postgraduate School's final exam scheduling system serves as a test case with which to compare two commercially available Computer-Aided Software Engineering (CASE) tools. The tools, Nastec Corporation's DesignAid (Release 3.55) and Index Technology's Excelerator (Release 1.7) are used to create Section 4.1 of two Abbreviated Systems Decision Papers to determine if their output can satisfy and should replace some of the Life...

  12. Development of a Computer-Aided System for Competitive Intelligence%竞争情报计算机辅助系统的开发

    Institute of Scientific and Technical Information of China (English)

    刘玉照; 曹君祥

    2000-01-01

    Competitive Information System (CIS) is a computer-aided system for competitive intelligence, and is designed for the information requirements of the corporate strategic management. The development of CIS is an important part of corporate Strategic Information Planning (SIP), and CIS directly supports the strategic objects of the corporate. The life cycle of CIS includes traditional life cycle, prototyping life cycle, object-oriented life cycle and so on.

  13. Benefit of computer-aided detection analysis for the detection of subsolid and solid lung nodules on thin- and thick-section CT.

    Science.gov (United States)

    Godoy, Myrna C B; Kim, Tae Jung; White, Charles S; Bogoni, Luca; de Groot, Patricia; Florin, Charles; Obuchowski, Nancy; Babb, James S; Salganicoff, Marcos; Naidich, David P; Anand, Vikram; Park, Sangmin; Vlahos, Ioannis; Ko, Jane P

    2013-01-01

    The objective of our study was to evaluate the impact of computer-aided detection (CAD) on the identification of subsolid and solid lung nodules on thin- and thick-section CT. For 46 chest CT examinations with ground-glass opacity (GGO) nodules, CAD marks computed using thin data were evaluated in two phases. First, four chest radiologists reviewed thin sections (reader(thin)) for nodules and subsequently CAD marks (reader(thin) + CAD(thin)). After 4 months, the same cases were reviewed on thick sections (reader(thick)) and subsequently with CAD marks (reader(thick) + CAD(thick)). Sensitivities were evaluated. Additionally, reader(thick) sensitivity with assessment of CAD marks on thin sections was estimated (reader(thick) + CAD(thin)). For 155 nodules (mean, 5.5 mm; range, 4.0-27.5 mm)-74 solid nodules, 22 part-solid (part-solid nodules), and 59 GGO nodules-CAD stand-alone sensitivity was 80%, 95%, and 71%, respectively, with three false-positives on average (0-12) per CT study. Reader(thin) + CAD(thin) sensitivities were higher than reader(thin) for solid nodules (82% vs 57%, p thick), reader(thick) + CAD(thick), reader(thick) + CAD(thin) were 40%, 58% (p thick); false-positive rates were 1.17, 1.19, and 1.26 per case for reader(thick), reader(thick) + CAD(thick), and reader(thick) + CAD(thin), respectively. Detection of GGO nodules and solid nodules is significantly improved with CAD. When interpretation is performed on thick sections, the benefit is greater when CAD marks are reviewed on thin rather than thick sections.

  14. Role of Computer Aided Diagnosis (CAD in the detection of pulmonary nodules on 64 row multi detector computed tomography

    Directory of Open Access Journals (Sweden)

    K Prakashini

    2016-01-01

    Full Text Available Aims and Objectives: To determine the overall performance of an existing CAD algorithm with thin-section computed tomography (CT in the detection of pulmonary nodules and to evaluate detection sensitivity at a varying range of nodule density, size, and location. Materials and Methods: A cross-sectional prospective study was conducted on 20 patients with 322 suspected nodules who underwent diagnostic chest imaging using 64-row multi-detector CT. The examinations were evaluated on reconstructed images of 1.4 mm thickness and 0.7 mm interval. Detection of pulmonary nodules, initially by a radiologist of 2 years experience (RAD and later by CAD lung nodule software was assessed. Then, CAD nodule candidates were accepted or rejected accordingly. Detected nodules were classified based on their size, density, and location. The performance of the RAD and CAD system was compared with the gold standard that is true nodules confirmed by consensus of senior RAD and CAD together. The overall sensitivity and false-positive (FP rate of CAD software was calculated. Observations and Results: Of the 322 suspected nodules, 221 were classified as true nodules on the consensus of senior RAD and CAD together. Of the true nodules, the RAD detected 206 (93.2% and 202 (91.4% by the CAD. CAD and RAD together picked up more number of nodules than either CAD or RAD alone. Overall sensitivity for nodule detection with the CAD program was 91.4%, and FP detection per patient was 5.5%. The CAD showed comparatively higher sensitivity for nodules of size 4-10 mm (93.4% and nodules in hilar (100% and central (96.5% location when compared to RAD′s performance. Conclusion: CAD performance was high in detecting pulmonary nodules including the small size and low-density nodules. CAD even with relatively high FP rate, assists and improves RAD′s performance as a second reader, especially for nodules located in the central and hilar region and for small nodules by saving RADs time.

  15. Computer-aided translation tools

    DEFF Research Database (Denmark)

    Christensen, Tina Paulsen; Schjoldager, Anne

    2016-01-01

    in Denmark is rather high in general, but limited in the case of machine translation (MT) tools: While most TSPs use translation-memory (TM) software, often in combination with a terminology management system (TMS), only very few have implemented MT, which is criticised for its low quality output, especially......The paper reports on a questionnaire survey from 2013 of the uptake and use of computer-aided translation (CAT) tools by Danish translation service providers (TSPs) and discusses how these tools appear to have impacted on the Danish translation industry. According to our results, the uptake...

  16. Evidence-based investigation of the influence of computer-aided detection of polyps on screening of colon cancer with CT colonography

    International Nuclear Information System (INIS)

    Yoshida, Hiroyuki

    2008-01-01

    Computed tomographic colonography (CTC), also known as virtual colonoscopy, is a CT examination of the colon for colorectal neoplasms. Recent large-scale clinical trials have demonstrated that CTC yields sensitivity comparable to optical colonoscopy in the detection of clinically significant polyps in a screening population, making CTC a promising technique for screening of colon cancer. For CTC to be a clinically practical means of screening, it must reliably and consistently detect polyps with high accuracy. However, high-level expertise is required to interpret the resulting CT images to find polyps, resulting in variable diagnostic accuracy among radiologists in the detection of polyps. A key technology to overcome this problem and to bring CTC to prime time for screening of colorectal cancer is computer-aided detection (CAD) of polyps. CAD automatically detects the locations of suspicious polyps in CTC images and presents them to radiologists. CAD has the potential to increase diagnostic performance in the detection of polyps as well as to reduce variability of the diagnostic accuracy among radiologists. This paper presents an evidence-based investigation of the influence of CAD on screening of colon cancer with CTC by describing the benefits of using CAD in the diagnosis of CTC, the fundamental CAD scheme for the detection of polyps in CTC, its detection performance, the effect on the improvement of detection performance, as well as the current and future challenges in CAD. (author)

  17. Improving digital breast tomosynthesis reading time: A pilot multi-reader, multi-case study using concurrent Computer-Aided Detection (CAD).

    Science.gov (United States)

    Balleyguier, Corinne; Arfi-Rouche, Julia; Levy, Laurent; Toubiana, Patrick R; Cohen-Scali, Franck; Toledano, Alicia Y; Boyer, Bruno

    2017-12-01

    Evaluate concurrent Computer-Aided Detection (CAD) with Digital Breast Tomosynthesis (DBT) to determine impact on radiologist performance and reading time. The CAD system detects and extracts suspicious masses, architectural distortions and asymmetries from DBT planes that are blended into corresponding synthetic images to form CAD-enhanced synthetic images. Review of CAD-enhanced images and navigation to corresponding planes to confirm or dismiss potential lesions allows radiologists to more quickly review DBT planes. A retrospective, crossover study with and without CAD was conducted with six radiologists who read an enriched sample of 80 DBT cases including 23 malignant lesions in 21 women. Area Under the Receiver Operating Characteristic (ROC) Curve (AUC) compared the readings with and without CAD to determine the effect of CAD on overall interpretation performance. Sensitivity, specificity, recall rate and reading time were also assessed. Multi-reader, multi-case (MRMC) methods accounting for correlation and requiring correct lesion localization were used to analyze all endpoints. AUCs were based on a 0-100% probability of malignancy (POM) score. Sensitivity and specificity were based on BI-RADS scores, where 3 or higher was positive. Average AUC across readers without CAD was 0.854 (range: 0.785-0.891, 95% confidence interval (CI): 0.769,0.939) and 0.850 (range: 0.746-0.905, 95% CI: 0.751,0.949) with CAD (95% CI for difference: -0.046,0.039), demonstrating non-inferiority of AUC. Average reduction in reading time with CAD was 23.5% (95% CI: 7.0-37.0% improvement), from an average 48.2 (95% CI: 39.1,59.6) seconds without CAD to 39.1 (95% CI: 26.2,54.5) seconds with CAD. Per-patient sensitivity was the same with and without CAD (0.865; 95% CI for difference: -0.070,0.070), and there was a small 0.022 improvement (95% CI for difference: -0.046,0.089) in per-lesion sensitivity from 0.790 without CAD to 0.812 with CAD. A slight reduction in specificity with a -0

  18. Application of a kernel-based online learning algorithm to the classification of nodule candidates in computer-aided detection of CT lung nodules

    International Nuclear Information System (INIS)

    Matsumoto, S.; Ohno, Y.; Takenaka, D.; Sugimura, K.; Yamagata, H.

    2007-01-01

    Classification of the nodule candidates in computer-aided detection (CAD) of lung nodules in CT images was addressed by constructing a nonlinear discriminant function using a kernel-based learning algorithm called the kernel recursive least-squares (KRLS) algorithm. Using the nodule candidates derived from the processing by a CAD scheme of 100 CT datasets containing 253 non-calcified nodules or 3 mm or larger as determined by the consensus of two thoracic radiologists, the following trial were carried out 100 times: by randomly selecting 50 datasets for training, a nonlinear discriminant function was obtained using the nodule candidates in the training datasets and tested with the remaining candidates; for comparison, a rule-based classification was tested in a similar manner. At the number of false positives per case of about 5, the nonlinear classification method showed an improved sensitivity of 80% (mean over the 100 trials) compared with 74% of the rule-based method. (orig.)

  19. Does computer-aided detection have a role in the arbitration of discordant double-reading opinions in a breast-screening programme?

    International Nuclear Information System (INIS)

    James, J.J.; Cornford, E.J.

    2009-01-01

    Aims: To investigate whether a computer-aided detection (CAD) system could act as an arbitrator of discordant double-reading opinions, replacing the need for an independent third film reader. Methods: The mammograms of the 240 women that underwent arbitration by an independent third reader were identified from the 16,629 women attending our screening centre between July 2003 and April 2004. Mammograms of the arbitration cases were digitized and analysed by a CAD system. To assess the ability of CAD to act as the arbitrator, the site of the CAD prompts was retrospectively compared to the site of any abnormality noted by the original film readers. If a CAD prompt was placed on a region marked by one of the film readers then the decision of CAD as the arbitrator was that the women should be recalled for further assessment. If no mark was placed then the region was considered low risk and the decision was not to recall. The decision of CAD as the arbitrator was retrospectively compared with the original recall decision of the independent third reader. Results: There were 21 cancer cases in the group of women undergoing arbitration, diagnosed both at the original screening episode and subsequently. The independent third reader recalled 15/18 (83%) of the cancers that corresponded with the arbitrated lesion. CAD as the arbitrator would have recalled 16/18 (89%) of the cancers that corresponded to the arbitrated lesion. CAD acting as the arbitrator would have resulted in a significant increase in normal women being recalled to assessment in the arbitration group (P < 0.001). The extra 50 recalls would have potentially increased the overall recall rate to assessment from 3.1 to 3.4%; a relative increase of 10%. Conclusions: The main effect of CAD acting as an arbitrator of discordant double-reading opinions is to increase the recall rate, significantly above what is found when arbitration is performed by an independent third reader. Using CAD as an arbitrator may be an

  20. STRATEGY FOR IMPROVEMENT OF SAFETY AND EFFICIENCY OF COMPUTER-AIDED DESIGN ANALYSIS OF CIVIL ENGINEERING STRUCTURES ON THE BASIS OF THE SYSTEM APPROACH

    Directory of Open Access Journals (Sweden)

    Zaikin Vladimir Genrikhovich

    2012-12-01

    Full Text Available The authors highlight three problems of the age of information technologies and proposes the strategy for their resolution in relation to the computer-aided design of civil engineering structures. The authors express their concerns in respect of globalization of software programmes designated for the analysis of civil engineering structures and employed outside of Russia. The problem of the poor quality of the input data has reached Russia. Lately, the rate of accidents of buildings and structures has been growing not only in Russia. Control over efficiency of design projects is hardly performed. This attitude should be changed. Development and introduction of CAD along with the application the efficient methods of projection of behaviour of building structures are in demand. Computer-aided calculations have the function of a logical nucleus, and they need proper control. The system approach to computer-aided calculations and technologies designated for the projection of accidents is formulated by the authors. Two tasks of the system approach and fundamentals of the strategy for its implementation are formulated. The study of cases of negative results of computer-aided design of engineering structures was performed and multi-component design patterns were developed. Conclusions concerning the results of researches aimed at regular and wide-scale implementation of the strategy fundamentals are formulated. Organizational and innovative actions concerning the projected behaviour of civil engineering structures proposed in the strategy are to facilitate: safety and reliability improvement of buildings and structures; saving of building materials and resources; improvement of labour efficiency of designers; modernization and improvement of accuracy of projected behaviour of buildings and building standards; closer ties between civil and building engineering researchers and construction companies; development of competitive environment to boost

  1. Computer aided control engineering

    DEFF Research Database (Denmark)

    Szymkat, Maciej; Ravn, Ole

    1997-01-01

    Current developments in the field of Computer Aided Control Engineering (CACE) have a visible impact on the design methodologies and the structure of the software tools supporting them. Today control engineers has at their disposal libraries, packages or programming environments that may...... in CACE enhancing efficient flow of information between the tools supporting the following phases of the design process. In principle, this flow has to be two-way, and more or less automated, in order to enable the engineer to observe the propagation of the particular design decisions taken at various...... levels.The major conclusions of the paper are related with identifying the factors affecting the software tool integration in a way needed to facilitate design "inter-phase" communication. These are: standard application interfaces, dynamic data exchange mechanisms, code generation techniques and general...

  2. Computer-aided diagnosis of mammographic microcalcification clusters

    International Nuclear Information System (INIS)

    Kallergi, Maria

    2004-01-01

    Computer-aided diagnosis techniques in medical imaging are developed for the automated differentiation between benign and malignant lesions and go beyond computer-aided detection by providing cancer likelihood for a detected lesion given image and/or patient characteristics. The goal of this study was the development and evaluation of a computer-aided detection and diagnosis algorithm for mammographic calcification clusters. The emphasis was on the diagnostic component, although the algorithm included automated detection, segmentation, and classification steps based on wavelet filters and artificial neural networks. Classification features were selected primarily from descriptors of the morphology of the individual calcifications and the distribution of the cluster. Thirteen such descriptors were selected and, combined with patient's age, were given as inputs to the network. The features were ranked and evaluated for the classification of 100 high-resolution, digitized mammograms containing biopsy-proven, benign and malignant calcification clusters. The classification performance of the algorithm reached a 100% sensitivity for a specificity of 85% (receiver operating characteristic area index A z =0.98±0.01). Tests of the algorithm under various conditions showed that the selected features were robust morphological and distributional descriptors, relatively insensitive to segmentation and detection errors such as false positive signals. The algorithm could exceed the performance of a similar visual analysis system that was used as basis for development and, combined with a simple image standardization process, could be applied to images from different imaging systems and film digitizers with similar sensitivity and specificity rates

  3. The utility of computer-aided-detection for the assessment of pulmonary arterial filling defects at CT angiography

    International Nuclear Information System (INIS)

    Roberts, H.C.; Walsham, A.; Colak, E.; Kashani, H.; Mongiardi, C.; Patsios, D.

    2007-01-01

    The purpose of this study is to validate a computer assisted detection (CAD) system for the detection of pulmonary intra-arterial filling defects and assess its utility for radiology readers of different levels of experience. Methods: 100 contrast-enhanced computed tomography pulmonary angiograms (CTPAs) performed to rule out pulmonary embolism (PE) were retrospectively analyzed; all were previously read by the chest radiologist on service and were re-assessed by a chest radiologist for the presence and location of PE. CTPAs were analyzed using the second generation CAD software pulmonary artery Patency Exam (PE trademark) tool, used with the ImageChecker registered CT (version 2.1 R2 Technology Inc., Santa Clara, CA). Each CAD mark was assigned one of the following interpretations: true positive, TP: intra-arterial filling defect found by CAD and the radiologist; false positive, FP: CAD mark that was not a filling defect; false negative, FN: filling defect found by the radiologist, but not by CAD. CAD performance was quantified on a per case basis; if CAD did not mark a study negative for PE, this was defined as true negative (TN). If CAD yielded FP marks only in a study positive for PE, this was counted as a FN case. All CTPAs were interpreted by four readers of different levels of experience, both without and with CAD. They recorded the reading time, the presence and location of PE, and the confidence in their diagnosis (1 = least, 2 moderately, 3 = very confident). Results: 21 cases were positive for PE. CAD showed marks in all 21 cases, but in three cases, all were FP marks (3 FN cases, 18 TP cases). Of the 79 exams negative for PE, 16 had no CAD marks (16 TN cases), 63 had at least one CAD mark (63 FP cases). On a case-basis, CAD sensitivity was 86%, negative predictive value was 84%, specificity 20%, positive predictive value (PPV) 22%. In the 21 positive cases, 93 filling defects were identified, of which 64 were correctly marked by CAD (sensitivity 69

  4. CT colonography: effect of computer-aided detection of colonic polyps as a second and concurrent reader for general radiologists with moderate experience in CT colonography

    International Nuclear Information System (INIS)

    Mang, Thomas; Ringel, Helmut; Weber, Michael; Bogoni, Luca; Anand, Vikram X.; Hermosillo, Gerardo; Raykar, Vikas; Salganicoff, Marcos; Wolf, Matthias; Chandra, Dass; Curtin, Andrew J.; Lev-Toaff, Anna S.; Noah, Ralph; Shaw, Robert; Summerton, Susan; Tappouni, Rafel F.R.; Obuchowski, Nancy A.

    2014-01-01

    To assess the effectiveness of computer-aided detection (CAD) as a second reader or concurrent reader in helping radiologists who are moderately experienced in computed tomographic colonography (CTC) to detect colorectal polyps. Seventy CTC datasets (34 patients: 66 polyps ≥6 mm; 36 patients: no abnormalities) were retrospectively reviewed by seven radiologists with moderate CTC experience. After primary unassisted evaluation, a CAD second read and, after a time interval of ≥4 weeks, a CAD concurrent read were performed. Areas under the receiver operating characteristic (ROC) curve (AUC), along with per-segment, per-polyp and per-patient sensitivities, and also reading times, were calculated for each reader with and without CAD. Of seven readers, 86 % and 71 % achieved a higher accuracy (segment-level AUC) when using CAD as second and concurrent reader respectively. Average segment-level AUCs with second and concurrent CAD (0.853 and 0.864) were significantly greater (p < 0.0001) than average AUC in the unaided evaluation (0.781). Per-segment, per-polyp, and per-patient sensitivities for polyps ≥6 mm were significantly higher in both CAD reading paradigms compared with unaided evaluation. Second-read CAD reduced readers' average segment and patient specificity by 0.007 and 0.036 (p = 0.005 and 0.011), respectively. CAD significantly improves the sensitivities of radiologists moderately experienced in CTC for polyp detection, both as second reader and concurrent reader. (orig.)

  5. Improved detection of pulmonary nodules on energy-subtracted chest radiographs with a commercial computer-aided diagnosis software: comparison with human observers

    International Nuclear Information System (INIS)

    Szucs-Farkas, Zsolt; Patak, Michael A.; Yuksel-Hatz, Seyran; Ruder, Thomas; Vock, Peter

    2010-01-01

    To retrospectively analyze the performance of a commercial computer-aided diagnosis (CAD) software in the detection of pulmonary nodules in original and energy-subtracted (ES) chest radiographs. Original and ES chest radiographs of 58 patients with 105 pulmonary nodules measuring 5-30 mm and images of 25 control subjects with no nodules were randomized. Five blinded readers evaluated firstly the original postero-anterior images alone and then together with the subtracted radiographs. In a second phase, original and ES images were analyzed by a commercial CAD program. CT was used as reference standard. CAD results were compared to the readers' findings. True-positive (TP) and false-positive (FP) findings with CAD on subtracted and non-subtracted images were compared. Depending on the reader's experience, CAD detected between 11 and 21 nodules missed by readers. Human observers found three to 16 lesions missed by the CAD software. CAD used with ES images produced significantly fewer FPs than with non-subtracted images: 1.75 and 2.14 FPs per image, respectively (p=0.029). The difference for the TP nodules was not significant (40 nodules on ES images and 34 lesions in non-subtracted radiographs, p = 0.142). CAD can improve lesion detection both on energy subtracted and non-subtracted chest images, especially for less experienced readers. The CAD program marked less FPs on energy-subtracted images than on original chest radiographs. (orig.)

  6. Computer-aided detection (CAD) of lung nodules in CT scans: radiologist performance and reading time with incremental CAD assistance

    International Nuclear Information System (INIS)

    Roos, Justus E.; Paik, David; Olsen, David; Liu, Emily G.; Leung, Ann N.; Mindelzun, Robert; Choudhury, Kingshuk R.; Napel, Sandy; Rubin, Geoffrey D.; Chow, Lawrence C.; Naidich, David P.

    2010-01-01

    The diagnostic performance of radiologists using incremental CAD assistance for lung nodule detection on CT and their temporal variation in performance during CAD evaluation was assessed. CAD was applied to 20 chest multidetector-row computed tomography (MDCT) scans containing 190 non-calcified ≥3-mm nodules. After free search, three radiologists independently evaluated a maximum of up to 50 CAD detections/patient. Multiple free-response ROC curves were generated for free search and successive CAD evaluation, by incrementally adding CAD detections one at a time to the radiologists' performance. The sensitivity for free search was 53% (range, 44%-59%) at 1.15 false positives (FP)/patient and increased with CAD to 69% (range, 59-82%) at 1.45 FP/patient. CAD evaluation initially resulted in a sharp rise in sensitivity of 14% with a minimal increase in FP over a time period of 100 s, followed by flattening of the sensitivity increase to only 2%. This transition resulted from a greater prevalence of true positive (TP) versus FP detections at early CAD evaluation and not by a temporal change in readers' performance. The time spent for TP (9.5 s ± 4.5 s) and false negative (FN) (8.4 s ± 6.7 s) detections was similar; FP decisions took two- to three-times longer (14.4 s ± 8.7 s) than true negative (TN) decisions (4.7 s ± 1.3 s). When CAD output is ordered by CAD score, an initial period of rapid performance improvement slows significantly over time because of non-uniformity in the distribution of TP CAD output and not to a changing reader performance over time. (orig.)

  7. Computer-aided detection of lung nodules on multidetector CT in concurrent-reader and second-reader modes: A comparative study

    International Nuclear Information System (INIS)

    Matsumoto, Sumiaki; Ohno, Yoshiharu; Aoki, Takatoshi; Yamagata, Hitoshi; Nogami, Munenobu; Matsumoto, Keiko; Yamashita, Yoshiko; Sugimura, Kazuro

    2013-01-01

    Purpose: To compare the reading times and detection performances of radiologists in concurrent-reader and second-reader modes of computer-aided detection (CAD) for lung nodules on multidetector computed tomography (CT). Materials and Methods: Fifty clinical multidetector CT datasets containing nodules up to 20 mm in diameter were retrospectively collected. For the detection and rating of non-calcified nodules larger than 4 mm in diameter, 6 radiologists (3 experienced radiologists and 3 resident radiologists) independently interpreted these datasets twice, once with concurrent-reader CAD and once with second-reader CAD. The reference standard of nodules in the datasets was determined by the consensus of two experienced chest radiologists. The reading times and detection performances in the two modes of CAD were statistically compared, where jackknife free-response receiver operating characteristic (JAFROC) analysis was used for the comparison of detection performances. Results: Two hundreds and seven nodules constituted the reference standard. Reading time was significantly shorter in the concurrent-reader mode than in the second-reader mode, with the mean reading time for the 6 radiologists being 132 s with concurrent-reader CAD and 210 s with second-reader CAD (p < 0.01). JAFROC analysis revealed no significant difference between the detection performances in the two modes, with the average figure-of-merit value for the 6 radiologists being 0.70 with concurrent-reader CAD and 0.72 with second-reader CAD (p = 0.35). Conclusion: In CAD for lung nodules on multidetector CT, the concurrent-reader mode is more time-efficient than the second-reader mode, and there can be no significant difference between the two modes in terms of detection performance of radiologists

  8. Computer aided analysis of disturbances

    International Nuclear Information System (INIS)

    Baldeweg, F.; Lindner, A.

    1986-01-01

    Computer aided analysis of disturbances and the prevention of failures (diagnosis and therapy control) in technological plants belong to the most important tasks of process control. Research in this field is very intensive due to increasing requirements to security and economy of process control and due to a remarkable increase of the efficiency of digital electronics. This publication concerns with analysis of disturbances in complex technological plants, especially in so called high risk processes. The presentation emphasizes theoretical concept of diagnosis and therapy control, modelling of the disturbance behaviour of the technological process and the man-machine-communication integrating artificial intelligence methods, e.g., expert system approach. Application is given for nuclear power plants. (author)

  9. Intelligent Support for a Computer Aided Design Optimisation Cycle

    OpenAIRE

    B. Dolšak; M. Novak; J. Kaljun

    2006-01-01

    It is becoming more and more evident that  adding intelligence  to existing computer aids, such as computer aided design systems, can lead to significant improvements in the effective and reliable performance of various engineering tasks, including design optimisation. This paper presents three different intelligent modules to be applied within a computer aided design optimisation cycle to enable more intelligent and less experience-dependent design performance. 

  10. Integral system for computer aided design of power line transmission towers; Sistema integral para el diseno asistido por computadora de torres de transmision

    Energy Technology Data Exchange (ETDEWEB)

    Nagore, Gabriel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1987-12-31

    The profitable use of the advantages offered by the computer aided design, through the integral system for the structural design of power transmission towers (SIDETT) will contribute to facilitate and improve the design of the structures that link the electric power generation centers with the consumers. [Espanol] El aprovechamiento de las ventajas que ofrece el diseno asistido por computadora, a traves del sistema integral para el diseno estructural de torres de transmision (SIDETT), contribuira a agilizar y mejorar el diseno de las estructuras que enlazan los centros de generacion de energia electrica con los consumidores.

  11. Integral system for computer aided design of power line transmission towers; Sistema integral para el diseno asistido por computadora de torres de transmision

    Energy Technology Data Exchange (ETDEWEB)

    Nagore, Gabriel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1986-12-31

    The profitable use of the advantages offered by the computer aided design, through the integral system for the structural design of power transmission towers (SIDETT) will contribute to facilitate and improve the design of the structures that link the electric power generation centers with the consumers. [Espanol] El aprovechamiento de las ventajas que ofrece el diseno asistido por computadora, a traves del sistema integral para el diseno estructural de torres de transmision (SIDETT), contribuira a agilizar y mejorar el diseno de las estructuras que enlazan los centros de generacion de energia electrica con los consumidores.

  12. A new parameter enhancing breast cancer detection in computer-aided diagnosis of X-ray mammograms

    International Nuclear Information System (INIS)

    Tanki, Nobuyoshi; Murase, Kenya; Nagao, Michinobu

    2006-01-01

    The purpose of this study was to introduce a new parameter which enhances breast cancer detection using X-ray mammography. We used the database of X-ray mammograms generated by the Japan Society of Radiological Technology. The new parameter called 'quasi-fractal dimension (Q-FD)' was calculated from the relationship between the cutoff values for the maximum image intensity in the lesion set at 21 levels from 20% to 100% at equal intervals and the number of pixels with an intensity exceeding the cutoff value. In addition to Q-FD, the image features such as curvature (C) and eccentricity (E) were extracted. The conventional fractal dimension (C-FD) was also calculated using the box-counting method. We used artificial neural networks (ANNs) as a classification method. When using C, E, C-FD and age as inputs in ANNs and taking the number of neurons in the hidden layer as 50, we found the area under the receiver operating characteristic curve (A Z ) was 0.87±0.07 in the task differentiating between benign and malignant masses. When Q-FD was added to inputs in addition to the above parameters, the A Z value was significantly improved to become 0.93±0.09. These results suggested that Q-FD is effective for discriminating between benign and malignant masses. (author)

  13. Design of the Digital Sky Survey DA and online system: A case history in the use of computer aided tools for data acquisition system design

    Science.gov (United States)

    Petravick, D.; Berman, E.; Nicinski, T.; Rechenmacher, R.; Oleynik, G.; Pordes, R.; Stoughton, C.

    1991-06-01

    As part of its expanding Astrophysics program, Fermilab is participating in the Digital Sky Survey (DSS). Fermilab is part of a collaboration involving University of Chicago, Princeton University, and the Institute of Advanced Studies (at Princeton). The DSS main results will be a photometric imaging survey and a redshift survey of galaxies and color-selected quasars over pi steradians of the Northern Galactic Cap. This paper focuses on our use of Computer Aided Software Engineering (CASE) in specifying the data system for DSS. Extensions to standard methodologies were necessary to compensate for tool shortcomings and to improve communication amongst the collaboration members. One such important extension was the incorporation of CASE information into the specification document.

  14. Does the accuracy of single reading with CAD (computer-aided detection) compare with that of double reading?: A review of the literature

    International Nuclear Information System (INIS)

    Bennett, R.L.; Blanks, R.G.; Moss, S.M.

    2006-01-01

    Aim: To examine current evidence to determine whether the accuracy of single reading with computed-aided detection (CAD) compares with that of double reading. Methods: We performed a literature review to identify studies where both protocols had been investigated and compared. We identified eight studies that compared single reading with CAD against double reading, of which six reported on comparisons of both sensitivity and specificity. Results: Of the six studies identified, three showed no differences in either sensitivity or specificity. One showed single reading with CAD had a higher sensitivity at the same specificity, another that single reading with CAD had a higher specificity at the same sensitivity. However, one study, in a real-life setting, showed that single reading with CAD had a higher sensitivity but a lower specificity. Conclusion: As the majority of the studies were not in a real-life setting, used test sets, lacked sufficient training in the use of CAD and simulated double reading (using a protocol of recall if one suggests), current evidence is therefore limited as to the accuracy, in terms of sensitivity and specificity, of single reading with CAD in comparison with the most common practice in the UK of double reading using a protocol of consensus or arbitration

  15. Time-efficient CT colonography interpretation using an advanced image-gallery-based, computer-aided ''first-reader'' workflow for the detection of colorectal adenomas

    International Nuclear Information System (INIS)

    Mang, Thomas; Ringl, Helmut; Weber, Michael; Mueller-Mang, Christina; Hermosillo, Gerardo; Wolf, Matthias; Bogoni, Luca; Salganicoff, Marcos; Raykar, Vikas; Graser, Anno

    2012-01-01

    To assess the performance of an advanced ''first-reader'' workflow for computer-aided detection (CAD) of colorectal adenomas ≥ 6 mm at computed tomographic colonography (CTC) in a low-prevalence cohort. A total of 616 colonoscopy-validated CTC patient-datasets were retrospectively reviewed by a radiologist using a ''first-reader'' CAD workflow. CAD detections were presented as galleries of six automatically generated two-dimensional (2D) and three-dimensional (3D) images together with interactive 3D target views and 2D multiplanar views of the complete dataset. Each patient-dataset was interpreted by initially using CAD image-galleries followed by a fast 2D review to address unprompted colonic areas. Per-patient, per-polyp, and per-adenoma sensitivities were calculated for lesions ≥ 6 mm. Statistical testing employed Fisher's exact and McNemar tests. In 91/616 patients, 131 polyps (92 adenomas, 39 non-adenomas) ≥ 6 mm and two cancers were identified by reference standard. Using the CAD gallery-based first-reader workflow, the radiologist detected all adenomas ≥ 10 mm (34/34) and cancers. Per-patient and polyp sensitivities for lesions ≥ 6 mm were 84.3 % (75/89), and 83.2 % (109/131), respectively, with 89.1 % (57/64) and 85.9 % (79/92) for adenomas. Overall specificity was 95.6 % (504/527). Mean interpretation time was 3.1 min per patient. A CAD algorithm, applied in an image-gallery-based first-reader workflow, can substantially decrease reading times while enabling accurate detection of colorectal adenomas in a low-prevalence population. (orig.)

  16. Computer-Aided Design in Further Education.

    Science.gov (United States)

    Ingham, Peter, Ed.

    This publication updates the 1982 occasional paper that was intended to foster staff awareness and assist colleges in Great Britain considering the use of computer-aided design (CAD) material in engineering courses. The paper begins by defining CAD and its place in the Integrated Business System with a brief discussion of the effect of CAD on the…

  17. Optimization of Network Topology in Computer-Aided Detection Schemes Using Phased Searching with NEAT in a Time-Scaled Framework.

    Science.gov (United States)

    Tan, Maxine; Pu, Jiantao; Zheng, Bin

    2014-01-01

    In the field of computer-aided mammographic mass detection, many different features and classifiers have been tested. Frequently, the relevant features and optimal topology for the artificial neural network (ANN)-based approaches at the classification stage are unknown, and thus determined by trial-and-error experiments. In this study, we analyzed a classifier that evolves ANNs using genetic algorithms (GAs), which combines feature selection with the learning task. The classifier named "Phased Searching with NEAT in a Time-Scaled Framework" was analyzed using a dataset with 800 malignant and 800 normal tissue regions in a 10-fold cross-validation framework. The classification performance measured by the area under a receiver operating characteristic (ROC) curve was 0.856 ± 0.029. The result was also compared with four other well-established classifiers that include fixed-topology ANNs, support vector machines (SVMs), linear discriminant analysis (LDA), and bagged decision trees. The results show that Phased Searching outperformed the LDA and bagged decision tree classifiers, and was only significantly outperformed by SVM. Furthermore, the Phased Searching method required fewer features and discarded superfluous structure or topology, thus incurring a lower feature computational and training and validation time requirement. Analyses performed on the network complexities evolved by Phased Searching indicate that it can evolve optimal network topologies based on its complexification and simplification parameter selection process. From the results, the study also concluded that the three classifiers - SVM, fixed-topology ANN, and Phased Searching with NeuroEvolution of Augmenting Topologies (NEAT) in a Time-Scaled Framework - are performing comparably well in our mammographic mass detection scheme.

  18. Computer-aided detection (CAD) and assessment of malignant lesions in the liver and lung using a novel PET/CT software tool. Initial results

    International Nuclear Information System (INIS)

    Hahn, Steffen; Heusner, T.; Forsting, M.; Antoch, G.; Zhou, X.; Zhan, Y.; Peng, Z.; Hamami, M.; Bockisch, A.

    2010-01-01

    Purpose: To determine the feasibility of a PET/CT software tool (PET computer-aided detection: PET-CAD) for automated detection and assessment of pulmonary and hepatic lesions. Materials and Methods: 20 consecutive patients with colorectal liver metastases and 20 consecutive patients suffering from non-small cell lung cancer (NSCLC) were examined with FDG-PET/CT. In a first step the maximum standardized uptake values (SUV max ) of non-tumorous liver and lung tissues were determined manually. This value was used as a threshold value for software-based lesion detection. The number of lesions detected, their SUV max , and their sizes in the x, y, and z-planes, as automatically provided by PET-CAD, were compared to visual lesion detection and manual measurements on CT. Results: The sensitivity for automated detection was 96% (86-99%) for colorectal liver metastases and 90% (70-99%) for lung lesions. The positive predictive value was 80% for liver and 68% for lung lesions. The mean SUV max of all lung lesions was 9.3 and 8.8 for the liver lesions. When assessed by PET-CAD, the mean lesion sizes for liver lesions in the x, y, and z-planes were 4.3 cm, 4.6 cm, and 4.2 cm compared to 3.5 cm, 3.8 cm, and 3.6 cm for manual measurements. The mean lesion sizes of lung lesions were 7.4 cm, 7.7 cm, and 8.4 cm in the x, y, and z-planes when assessed by PET-CAD compared to 5.8 cm, 6.1 cm, and 7.1 cm when measured manually. Using manual assessment, the lesion sizes were significantly smaller in all planes (p < 0.005). Conclusion: Software tools for automated lesion detection and assessment are expected to improve the clinical PET/CT workflow. Before implementation in the clinical routine, further improvements to the measurement accuracy are required. (orig.)

  19. Computer-aided cleanup

    International Nuclear Information System (INIS)

    Williams, J.; Jones, B.

    1994-01-01

    In late 1992, the remedial investigation of operable unit 2 at the Department of Energy (DOE) Superfund site in Fernald, Ohio was in trouble. Despite years of effort--including an EPA-approved field-investigation work plan, 123 soil borings, 51 ground-water-monitoring wells, analysis of more than 650 soil and ground-water samples, and preparation of a draft remedial-investigation (RI) report--it was not possible to conclude if contaminated material in the unit was related to ground-water contamination previously detected beneath and beyond the site boundary. Compounding the problem, the schedule for the RI, feasibility study and record of decision for operable unit 2 was governed by a DOE-EPA consent agreement stipulating penalties of up to $10,000 per week for not meeting scheduled milestones--and time was running out. An advanced three-dimensional computer model confirmed that radioactive wastes dumped at the Fernald, Ohio Superfund site had contaminated ground water, after years of previous testing has been inconclusive. The system is now being used to aid feasibility and design work on the more-than-$1 billion remediation project

  20. Computer-aided detection of artificial pulmonary nodules using an ex vivo lung phantom: influence of exposure parameters and iterative reconstruction.

    Science.gov (United States)

    Wielpütz, Mark O; Wroblewski, Jacek; Lederlin, Mathieu; Dinkel, Julien; Eichinger, Monika; Koenigkam-Santos, M; Biederer, Jürgen; Kauczor, Hans-Ulrich; Puderbach, Michael U; Jobst, Bertram J

    2015-05-01

    To evaluate the influence of exposure parameters and raw-data based iterative reconstruction (IR) on the performance of computer-aided detection (CAD) of pulmonary nodules on chest multidetector computed tomography (MDCT). Seven porcine lung explants were inflated in a dedicated ex vivo phantom shell and prepared with n=162 artificial nodules of a clinically relevant volume and maximum diameter (46-1063 μl, and 6.2-21.5 mm). n=118 nodules were solid and n=44 part-solid. MDCT was performed with different combinations of 120 and 80 kV with 120, 60, 30 and 12 mA*s, and reconstructed with both filtered back projection (FBP) and IR. Subsequently, 16 datasets per lung were subjected to dedicated CAD software. The rate of true positive, false negative and false positive CAD marks was measured for each reconstruction. The rate of true positive findings ranged between 88.9-91.4% for FBP and 88.3-90.1% for IR (n.s.) with most exposure settings, but was significantly lower with the combination of 80 kV and 12 mA*s (80.9% and 81.5%, respectively, pvolumes 300 μl (p<0.05). Similarly, it was significantly lower for diameters <12 mm compared to ≥12 mm (p<0.05). The rate of true positives for solid and part-solid nodules was similar. Nodule CAD on chest MDCT is robust over a wide range of exposure settings. Noise reduction by IR is not detrimental for CAD, and may be used to improve image quality in the setting of low-dose MDCT for lung cancer screening. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Computer aided detection in prostate cancer diagnostics: A promising alternative to biopsy? A retrospective study from 104 lesions with histological ground truth.

    Directory of Open Access Journals (Sweden)

    Anika Thon

    Full Text Available Prostate cancer (PCa diagnosis by means of multiparametric magnetic resonance imaging (mpMRI is a current challenge for the development of computer-aided detection (CAD tools. An innovative CAD-software (Watson Elementary™ was proposed to achieve high sensitivity and specificity, as well as to allege a correlate to Gleason grade.To assess the performance of Watson Elementary™ in automated PCa diagnosis in our hospital´s database of MRI-guided prostate biopsies.The evaluation was retrospective for 104 lesions (47 PCa, 57 benign from 79, 64.61±6.64 year old patients using 3T T2-weighted imaging, Apparent Diffusion Coefficient (ADC maps and dynamic contrast enhancement series. Watson Elementary™ utilizes signal intensity, diffusion properties and kinetic profile to compute a proportional Gleason grade predictor, termed Malignancy Attention Index (MAI. The analysis focused on (i the CAD sensitivity and specificity to classify suspect lesions and (ii the MAI correlation with the histopathological ground truth.The software revealed a sensitivity of 46.80% for PCa classification. The specificity for PCa was found to be 75.43% with a positive predictive value of 61.11%, a negative predictive value of 63.23% and a false discovery rate of 38.89%. CAD classified PCa and benign lesions with equal probability (P 0.06, χ2 test. Accordingly, receiver operating characteristic analysis suggests a poor predictive value for MAI with an area under curve of 0.65 (P 0.02, which is not superior to the performance of board certified observers. Moreover, MAI revealed no significant correlation with Gleason grade (P 0.60, Pearson´s correlation.The tested CAD software for mpMRI analysis was a weak PCa biomarker in this dataset. Targeted prostate biopsy and histology remains the gold standard for prostate cancer diagnosis.

  2. Computer aided fault tree synthesis

    International Nuclear Information System (INIS)

    Poucet, A.

    1983-01-01

    Nuclear as well as non-nuclear organisations are showing during the past few years a growing interest in the field of reliability analysis. This urges for the development of powerful, state of the art methods and computer codes for performing such analysis on complex systems. In this report an interactive, computer aided approach is discussed, based on the well known fault tree technique. The time consuming and difficut task of manually constructing a system model (one or more fault trees) is replaced by an efficient interactive procedure in which the flexibility and the learning process inherent to the manual approach are combined with the accuracy in the modelling and the speed of the fully automatical approach. The method presented is based upon the use of a library containing component models. The possibility of setting up a standard library of models of general use and the link with a data collection system are discussed. The method has been implemented in the CAFTS-SALP software package which is described shortly in the report

  3. System of diagnosis of generators computer aided integrated into a movable laboratory; Sistema de diagnostico de generadores asistido por computadora integrado a un laboratorio movil

    Energy Technology Data Exchange (ETDEWEB)

    De la Torre Vega, H. Octavio; Escorsa Morales, Oscar; Castaneda Parra, Adelina; Garcia- Colon H, Rodolfo [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico); Lopez Azamar, Ernesto [Comision Federal de Electricidad (Mexico)

    1999-07-01

    The development of the Movable Laboratory is presented, which will allow to combine and document the knowledge acquired by more than ten years of experience in diagnosis of electrical generators. The development of the project is divided into three main parts: laboratory design, data acquisition system (Datec) and system of diagnosis of generators computer aided (Cadis). [Spanish] Se presenta el desarrollo del Laboratorio Movil, el cual permitira conjuntar y documentar el conocimiento adquirido por mas de diez anos de experiencia en diagnostico de generadores electricos. El desarrollo del proyecto se divide en tres grandes partes: diseno de laboratorio, sistema de adquisicion de datos (Datec) y sistema de diagnostico de generadores asistido por computadora (Cadis).

  4. Computer-Aided Modeling Framework

    DEFF Research Database (Denmark)

    Fedorova, Marina; Sin, Gürkan; Gani, Rafiqul

    Models are playing important roles in design and analysis of chemicals based products and the processes that manufacture them. Computer-aided methods and tools have the potential to reduce the number of experiments, which can be expensive and time consuming, and there is a benefit of working...... development and application. The proposed work is a part of the project for development of methods and tools that will allow systematic generation, analysis and solution of models for various objectives. It will use the computer-aided modeling framework that is based on a modeling methodology, which combines....... In this contribution, the concept of template-based modeling is presented and application is highlighted for the specific case of catalytic membrane fixed bed models. The modeling template is integrated in a generic computer-aided modeling framework. Furthermore, modeling templates enable the idea of model reuse...

  5. Massive-training artificial neural network (MTANN) for reduction of false positives in computer-aided detection of polyps: Suppression of rectal tubes

    International Nuclear Information System (INIS)

    Suzuki, Kenji; Yoshida, Hiroyuki; Naeppi, Janne; Dachman, Abraham H.

    2006-01-01

    One of the limitations of the current computer-aided detection (CAD) of polyps in CT colonography (CTC) is a relatively large number of false-positive (FP) detections. Rectal tubes (RTs) are one of the typical sources of FPs because a portion of a RT, especially a portion of a bulbous tip, often exhibits a cap-like shape that closely mimics the appearance of a small polyp. Radiologists can easily recognize and dismiss RT-induced FPs; thus, they may lose their confidence in CAD as an effective tool if the CAD scheme generates such ''obvious'' FPs due to RTs consistently. In addition, RT-induced FPs may distract radiologists from less common true positives in the rectum. Therefore, removal RT-induced FPs as well as other types of FPs is desirable while maintaining a high sensitivity in the detection of polyps. We developed a three-dimensional (3D) massive-training artificial neural network (MTANN) for distinction between polyps and RTs in 3D CTC volumetric data. The 3D MTANN is a supervised volume-processing technique which is trained with input CTC volumes and the corresponding ''teaching'' volumes. The teaching volume for a polyp contains a 3D Gaussian distribution, and that for a RT contains zeros for enhancement of polyps and suppression of RTs, respectively. For distinction between polyps and nonpolyps including RTs, a 3D scoring method based on a 3D Gaussian weighting function is applied to the output of the trained 3D MTANN. Our database consisted of CTC examinations of 73 patients, scanned in both supine and prone positions (146 CTC data sets in total), with optical colonoscopy as a reference standard for the presence of polyps. Fifteen patients had 28 polyps, 15 of which were 5-9 mm and 13 were 10-25 mm in size. These CTC cases were subjected to our previously reported CAD scheme that included centerline-based segmentation of the colon, shape-based detection of polyps, and reduction of FPs by use of a Bayesian neural network based on geometric and texture

  6. Computer-aided diagnostic scheme for the detection of lung nodules on chest radiographs: Localized search method based on anatomical classification

    International Nuclear Information System (INIS)

    Shiraishi, Junji; Li Qiang; Suzuki, Kenji; Engelmann, Roger; Doi, Kunio

    2006-01-01

    We developed an advanced computer-aided diagnostic (CAD) scheme for the detection of various types of lung nodules on chest radiographs intended for implementation in clinical situations. We used 924 digitized chest images (992 noncalcified nodules) which had a 500x500 matrix size with a 1024 gray scale. The images were divided randomly into two sets which were used for training and testing of the computerized scheme. In this scheme, the lung field was first segmented by use of a ribcage detection technique, and then a large search area (448x448 matrix size) within the chest image was automatically determined by taking into account the locations of a midline and a top edge of the segmented ribcage. In order to detect lung nodule candidates based on a localized search method, we divided the entire search area into 7x7 regions of interest (ROIs: 64x64 matrix size). In the next step, each ROI was classified anatomically into apical, peripheral, hilar, and diaphragm/heart regions by use of its image features. Identification of lung nodule candidates and extraction of image features were applied for each localized region (128x128 matrix size), each having its central part (64x64 matrix size) located at a position corresponding to a ROI that was classified anatomically in the previous step. Initial candidates were identified by use of the nodule-enhanced image obtained with the average radial-gradient filtering technique, in which the filter size was varied adaptively depending on the location and the anatomical classification of the ROI. We extracted 57 image features from the original and nodule-enhanced images based on geometric, gray-level, background structure, and edge-gradient features. In addition, 14 image features were obtained from the corresponding locations in the contralateral subtraction image. A total of 71 image features were employed for three sequential artificial neural networks (ANNs) in order to reduce the number of false-positive candidates. All

  7. Computer aided diagnosis of diabetic peripheral neuropathy

    Science.gov (United States)

    Chekh, Viktor; Soliz, Peter; McGrew, Elizabeth; Barriga, Simon; Burge, Mark; Luan, Shuang

    2014-03-01

    Diabetic peripheral neuropathy (DPN) refers to the nerve damage that can occur in diabetes patients. It most often affects the extremities, such as the feet, and can lead to peripheral vascular disease, deformity, infection, ulceration, and even amputation. The key to managing diabetic foot is prevention and early detection. Unfortunately, current existing diagnostic techniques are mostly based on patient sensations and exhibit significant inter- and intra-observer differences. We have developed a computer aided diagnostic (CAD) system for diabetic peripheral neuropathy. The thermal response of the feet of diabetic patients following cold stimulus is captured using an infrared camera. The plantar foot in the images from a thermal video are segmented and registered for tracking points or specific regions. The temperature recovery of each point on the plantar foot is extracted using our bio-thermal model and analyzed. The regions that exhibit abnormal ability to recover are automatically identified to aid the physicians to recognize problematic areas. The key to our CAD system is the segmentation of infrared video. The main challenges for segmenting infrared video compared to normal digital video are (1) as the foot warms up, it also warms up the surrounding, creating an ever changing contrast; and (2) there may be significant motion during imaging. To overcome this, a hybrid segmentation algorithm was developed based on a number of techniques such as continuous max-flow, model based segmentation, shape preservation, convex hull, and temperature normalization. Verifications of the automatic segmentation and registration using manual segmentation and markers show good agreement.

  8. A Simple Method for Determining Thermal Expansion Coefficient of Solid Materials with a Computer-aided Electromagnetic Dilatometer Measuring System

    Directory of Open Access Journals (Sweden)

    Z. EZZOUINE

    2015-07-01

    Full Text Available In this study, we present a newly designed electromagnetic dilatometer with micrometer accuracy for the measurement of the coefficient of thermal expansion of a solid in the 30 °C – 96 °C temperature range .The device has a graphical user interface to view real time data measurement. Iron and copper were subjected to temperature change in the thermal expansion experiment causing them to expand linearly. The voltage delivered in the electromagnetic dilatometer system, which includes the information about linear expansion and temperature change were transferred to a computer via a data acquisition card, presented by a program created in the LabVIEW environment, and the amount of linear expansion was detected in real time. The minimal change in length of the sample that can be resolved is 5µm, which yields the sensitivity comprised between 10-4 µm and 10-5 µm. In order to calibrate the electromagnetic dilatometer, thermal expansion coefficients of copper and Iron have been measured. By this technique, the thermal expansion coefficient can be determined with an acceptable accuracy. The present results appear also to agree well with those reported previously in the literature.

  9. Diagnosis of osteoporosis from dental panoramic radiographs using the support vector machine method in a computer-aided system

    International Nuclear Information System (INIS)

    Kavitha, M S; Asano, Akira; Taguchi, Akira; Kurita, Takio; Sanada, Mitsuhiro

    2012-01-01

    Early diagnosis of osteoporosis can potentially decrease the risk of fractures and improve the quality of life. Detection of thin inferior cortices of the mandible on dental panoramic radiographs could be useful for identifying postmenopausal women with low bone mineral density (BMD) or osteoporosis. The aim of our study was to assess the diagnostic efficacy of using kernel-based support vector machine (SVM) learning regarding the cortical width of the mandible on dental panoramic radiographs to identify postmenopausal women with low BMD. We employed our newly adopted SVM method for continuous measurement of the cortical width of the mandible on dental panoramic radiographs to identify women with low BMD or osteoporosis. The original X-ray image was enhanced, cortical boundaries were determined, distances among the upper and lower boundaries were evaluated and discrimination was performed by a radial basis function. We evaluated the diagnostic efficacy of this newly developed method for identifying women with low BMD (BMD T-score of -1.0 or less) at the lumbar spine and femoral neck in 100 postmenopausal women (≥50 years old) with no previous diagnosis of osteoporosis. Sixty women were used for system training, and 40 were used in testing. The sensitivity and specificity using RBF kernel-SVM method for identifying women with low BMD were 90.9% [95% confidence interval (CI), 85.3-96.5] and 83.8% (95% CI, 76.6-91.0), respectively at the lumbar spine and 90.0% (95% CI, 84.1-95.9) and 69.1% (95% CI, 60.1-78.6), respectively at the femoral neck. The sensitivity and specificity for identifying women with low BMD at either the lumbar spine or femoral neck were 90.6% (95% CI, 92.0-100) and 80.9% (95% CI, 71.0-86.9), respectively. Our results suggest that the newly developed system with the SVM method would be useful for identifying postmenopausal women with low skeletal BMD

  10. Fail-safe computer-aided operations control system for the transrapid maglev high-speed railway

    Energy Technology Data Exchange (ETDEWEB)

    Burkert, S [Siemens AG, Braunschweig (Germany); Eilers, H [Siemens AG, Braunschweig (Germany); Freitag, V [Siemens AG, Braunschweig (Germany); Knigge, R [Siemens AG, Braunschweig (Germany)

    1996-12-31

    The wide variety of control and safety functions for the Transrapid need to be interlinked in the operations control system. These functions are grouped according to their main focus and located in the subsystems `operations control centre`, `decentralised operations control system` and `on-board operations control system`. The paper describes the operations control system OCS. (HW)

  11. Solitary Pulmonary Nodule on Helical Dynamic CT Scans: Analysis of the Enhancement Patterns Using a Computer-Aided Diagnosis (CAD) System

    International Nuclear Information System (INIS)

    Choi, Eun Jung; Jin, Gong Yong; Han, Young Min; Lee, Young Sun; Kweon, Keun Sang

    2008-01-01

    We wanted to investigate the usefulness of a computer-aided diagnosis (CAD) system in assisting radiologists to diagnosis malignant solitary pulmonary nodules (SPNs), as compared with diagnosing SPNs with using direct personal drawing. Forty patients with SPNs were analyzed. After the pre-contrast scan was performed, an additional ten series of post-contrast images were obtained at 20-second intervals. Two investigators measured the attenuation values of the SPNs: a radiologist who drew the regions of interest (ROIs), and a technician who used a CAD system. The Bland and Altman plots were used to compare the net enhancement between a CAD system and direct personal drawing. The diagnostic characteristics of the malignant SPNs were calculated by considering the CAD and direct personal drawing and with using Fisher's exact test. On the Bland and Altman plot, the net enhancement difference between the CAD system and direct personal drawing was not significant (within ± 2 standard deriation). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of diagnosing malignant SPNs using CAD was 92%, 85%, 75%, 96% and 88%, respectively. The sensitivity, specificity, PPV, NPV and accuracy of diagnosing malignant SPNs using direct drawing was 92%, 89%, 79%, 92% and 88%, respectively. The CAD system was a useful tool for diagnosing malignant SPNs

  12. Promoting independence, health and well-being for older people: a feasibility study of computer-aided health and social risk appraisal system in primary care.

    Science.gov (United States)

    Walters, Kate; Kharicha, Kalpa; Goodman, Claire; Handley, Melanie; Manthorpe, Jill; Cattan, Mima; Morris, Steve; Clarke, Caroline S; Round, Jeff; Iliffe, Steve

    2017-03-24

    With population ageing, research is needed into new low-cost, scalable methods of effective promotion of health and wellbeing for older people. We aimed to assess feasibility, reach and costs of implementing a new tailored computer-aided health and social risk appraisal system in primary care. Design: Feasibility study. Five General Practices in London (Ealing) and Hertfordshire, United Kingdom (UK) Participants: Random sample of patients aged 65 + years. The Multi-dimensional Risk Appraisal for Older people (MRA-O) system includes: 1) Postal questionnaire including health, lifestyle, social and environmental domains; 2) Software system generating a personalised feedback report with advice on health and wellbeing; 3) Follow-up of people with new concerning or complex needs by GPs or practice nurses. Feasibility of implementation; participant wellbeing, functional ability and quality of life; social needs, health risks, potential lifestyle changes; and costs of implementation. Response rates to initial postal invitations were low (526/1550, 34%). Of these, 454/526 (86%) completed MRA-O assessments. Compared to local UK Census data on older people, participants were younger, more were owner-occupiers and fewer were from ethnic minority groups than expected. A range of problems was identified by participants, including pain in last week (269/438, 61.4%), low physical activity (173/453, 38.2%), sedentary lifestyle (174/447, 38.3%), falls (117/439, 26.7%), incontinence (111/441 25.2%), impaired vision 116/451 (25.7%), impaired hearing (145/431, 33.6%), depressed mood (71/451, 15.7%), impaired memory (44/444 9.9%), social isolation (46/449, 10.2%) and loneliness (31/442, 7.0%). Self-rated health was good/excellent in 312/437 (71.4%), and quality of life and well-being were slightly above age-specific population norms. Implementation costs were low. Practices reviewed medical records of 143/454 (31.5%) of participants as a consequence of their responses, and actively

  13. To the problem of reliability standardization in computer-aided manufacturing at NPP units

    International Nuclear Information System (INIS)

    Yastrebenetskij, M.A.; Shvyryaev, Yu.V.; Spektor, L.I.; Nikonenko, I.V.

    1989-01-01

    The problems of reliability standardization in computer-aided manufacturing of NPP units considering the following approaches: computer-aided manufacturing of NPP units as a part of automated technological complex; computer-aided manufacturing of NPP units as multi-functional system, are analyzed. Selection of the composition of reliability indeces for computer-aided manufacturing of NPP units for each of the approaches considered is substantiated

  14. Computer aids for plant operators

    International Nuclear Information System (INIS)

    Joly, J.P.

    1992-01-01

    For some time, particularly since the TMI accident, nuclear power plant operators have been aware of the difficulties involved in diagnosing accidents and returning plants to their stable, safe operating mode. There are various possible solutions to these problems: improve control organization during accident situations, rewrite control procedures, integrate safety engineers in shifts, improve control rooms, and implement additional computer aids. The purpose of this presentation is to describe the efforts undertaken by EDF over the last few years in this field

  15. A schema for knowledge representation and its implementation in a computer-aided design and manufacturing system

    Energy Technology Data Exchange (ETDEWEB)

    Tamir, D.E.

    1989-01-01

    Modularity in the design and implementation of expert systems relies upon cooperation among the expert systems and communication of knowledge between them. A prerequisite for an effective modular approach is some standard for knowledge representation to be used by the developers of the different modules. In this work the author presents a schema for knowledge representation, and apply this schema in the design of a rule-based expert system. He also implements a cooperative expert system using the proposed knowledge representation method. A knowledge representation schema is a formal specification of the internal, conceptual, and external components of a knowledge base, each specified in a separate schema. The internal schema defines the structure of a knowledge base, the conceptual schema defines the concepts, and the external schema formalizes the pragmatics of a knowledge base. The schema is the basis for standardizing knowledge representation systems and it is used in the various phases of design and specification of the knowledge base. A new model of knowledge representation based on a pattern recognition interpretation of implications is developed. This model implements the concept of linguistic variables and can, therefore, emulate human reasoning with linguistic imprecision. The test case for the proposed schema of knowledge representation is a system is a cooperative expert system composed of two expert systems. This system applies a pattern recognition interpretation of a generalized one-variable implication with linguistic variables.

  16. Comparison between low-cost marker-less and high-end marker-based motion capture systems for the computer-aided assessment of working ergonomics.

    Science.gov (United States)

    Patrizi, Alfredo; Pennestrì, Ettore; Valentini, Pier Paolo

    2016-01-01

    The paper deals with the comparison between a high-end marker-based acquisition system and a low-cost marker-less methodology for the assessment of the human posture during working tasks. The low-cost methodology is based on the use of a single Microsoft Kinect V1 device. The high-end acquisition system is the BTS SMART that requires the use of reflective markers to be placed on the subject's body. Three practical working activities involving object lifting and displacement have been investigated. The operational risk has been evaluated according to the lifting equation proposed by the American National Institute for Occupational Safety and Health. The results of the study show that the risk multipliers computed from the two acquisition methodologies are very close for all the analysed activities. In agreement to this outcome, the marker-less methodology based on the Microsoft Kinect V1 device seems very promising to promote the dissemination of computer-aided assessment of ergonomics while maintaining good accuracy and affordable costs. PRACTITIONER’S SUMMARY: The study is motivated by the increasing interest for on-site working ergonomics assessment. We compared a low-cost marker-less methodology with a high-end marker-based system. We tested them on three different working tasks, assessing the working risk of lifting loads. The two methodologies showed comparable precision in all the investigations.

  17. Computer aided modeling and expert systems add a needed dimension to water management in power plant operations

    International Nuclear Information System (INIS)

    Gill, P.H. Jr.

    1991-01-01

    This paper reports on computer modeling and expert systems applications in water management used to develop appropriate treatment recommendations and monitoring/control functions. Chemical treatment program development in recirculating cooling water (CALGUARD), one-through scale inhibition (THRUGARUD), once through corrosion control (OSCAR), as well as internal boiler water chemistry control (POWER-CHEM), and on-line real time system monitoring (HELMSMAN) plan an increasingly important role in power plant water management practices

  18. Investigations to the suitability of a computer-aided design system for mechanical construction in the ZAT of KFA Juelich

    International Nuclear Information System (INIS)

    Schoerner, M.; Koch, R.; Cordewiner, H.J.; Bachner, E.

    1983-06-01

    There is an extensive range of CAD systems in the marketplace which have been developed by various institutions for different types of applications and for different products, in some cases linked to specific hardware. Apart from such obvious features like prices, rates of sale and computer performance, other criteria such as documentation, ease of adaption and expansion, which are, as a rule, difficult to judge and quantify, play a decisive role. As an optimal CAD system does not exist in respect of every type of application the intended usage must be taken seriously into consideration when selecting a CAD system. On the basis of fundamental investigations of the suitability of CAD for the department for mechanical construction of ZAT at the KFA Juelich, the requirements and special needs of the construction process in the ZAT have been examined. In a short survey of the available CAD-systems a pre choice on the basis of some definitive musts has been made. The performance profile of the remaining systems has been thouroughly investigated and compared with the requirements of the ZAT. Thus the necessary decisions can be made on the basis of documented assessments. (orig.) [de

  19. Decision trees and integrated features for computer aided mammographic screening

    Energy Technology Data Exchange (ETDEWEB)

    Kegelmeyer, W.P. Jr.; Groshong, B.; Allmen, M.; Woods, K.

    1997-02-01

    Breast cancer is a serious problem, which in the United States causes 43,000 deaths a year, eventually striking 1 in 9 women. Early detection is the only effective countermeasure, and mass mammography screening is the only reliable means for early detection. Mass screening has many shortcomings which could be addressed by a computer-aided mammographic screening system. Accordingly, we have applied the pattern recognition methods developed in earlier investigations of speculated lesions in mammograms to the detection of microcalcifications and circumscribed masses, generating new, more rigorous and uniform methods for the detection of both those signs. We have also improved the pattern recognition methods themselves, through the development of a new approach to combinations of multiple classifiers.

  20. Design analysis and computer-aided performance evaluation of shuttle orbiter electrical power system. Volume 1: Summary

    Science.gov (United States)

    1974-01-01

    Studies were conducted to develop appropriate space shuttle electrical power distribution and control (EPDC) subsystem simulation models and to apply the computer simulations to systems analysis of the EPDC. A previously developed software program (SYSTID) was adapted for this purpose. The following objectives were attained: (1) significant enhancement of the SYSTID time domain simulation software, (2) generation of functionally useful shuttle EPDC element models, and (3) illustrative simulation results in the analysis of EPDC performance, under the conditions of fault, current pulse injection due to lightning, and circuit protection sizing and reaction times.

  1. Computer-Aided-Design of the Hydraulic System of Three-Dimensional Cartridge Valve Blocks (Selected Articles)

    Science.gov (United States)

    1991-03-21

    sectional representation of the spatial figure can be correctly determined. 6 The AutoLisp language system in the AutoCAD software provides the most...softwares are developed on the 32-bit machines and little progress has been reported for the 16-bit machines. Even the AutoCAD is a two-ard-a-half... AutoCAD software as the basis, developed the design package of 3-D cartridge valve blocks on IM PC/AT. To realize the 3-D displaying of cartridge valves

  2. Investigation of CPD and HMDS Sample Preparation Techniques for Cervical Cells in Developing Computer-Aided Screening System Based on FE-SEM/EDX

    Science.gov (United States)

    Ng, Siew Cheok; Abu Osman, Noor Azuan

    2014-01-01

    This paper investigated the effects of critical-point drying (CPD) and hexamethyldisilazane (HMDS) sample preparation techniques for cervical cells on field emission scanning electron microscopy and energy dispersive X-ray (FE-SEM/EDX). We investigated the visualization of cervical cell image and elemental distribution on the cervical cell for two techniques of sample preparation. Using FE-SEM/EDX, the cervical cell images are captured and the cell element compositions are extracted for both sample preparation techniques. Cervical cell image quality, elemental composition, and processing time are considered for comparison of performances. Qualitatively, FE-SEM image based on HMDS preparation technique has better image quality than CPD technique in terms of degree of spread cell on the specimen and morphologic signs of cell deteriorations (i.e., existence of plate and pellet drying artifacts and membrane blebs). Quantitatively, with mapping and line scanning EDX analysis, carbon and oxygen element compositions in HMDS technique were higher than the CPD technique in terms of weight percentages. The HMDS technique has shorter processing time than the CPD technique. The results indicate that FE-SEM imaging, elemental composition, and processing time for sample preparation with the HMDS technique were better than CPD technique for cervical cell preparation technique for developing computer-aided screening system. PMID:25610902

  3. Multicenter study of quantitative computed tomography analysis using a computer-aided three-dimensional system in patients with idiopathic pulmonary fibrosis.

    Science.gov (United States)

    Iwasawa, Tae; Kanauchi, Tetsu; Hoshi, Toshiko; Ogura, Takashi; Baba, Tomohisa; Gotoh, Toshiyuki; Oba, Mari S

    2016-01-01

    To evaluate the feasibility of automated quantitative analysis with a three-dimensional (3D) computer-aided system (i.e., Gaussian histogram normalized correlation, GHNC) of computed tomography (CT) images from different scanners. Each institution's review board approved the research protocol. Informed patient consent was not required. The participants in this multicenter prospective study were 80 patients (65 men, 15 women) with idiopathic pulmonary fibrosis. Their mean age was 70.6 years. Computed tomography (CT) images were obtained by four different scanners set at different exposures. We measured the extent of fibrosis using GHNC, and used Pearson's correlation analysis, Bland-Altman plots, and kappa analysis to directly compare the GHNC results with manual scoring by radiologists. Multiple linear regression analysis was performed to determine the association between the CT data and forced vital capacity (FVC). For each scanner, the extent of fibrosis as determined by GHNC was significantly correlated with the radiologists' score. In multivariate analysis, the extent of fibrosis as determined by GHNC was significantly correlated with FVC (p < 0.001). There was no significant difference between the results obtained using different CT scanners. Gaussian histogram normalized correlation was feasible, irrespective of the type of CT scanner used.

  4. A Computer-Aided Diagnosis System Using Artificial Intelligence for the Diagnosis and Characterization of Thyroid Nodules on Ultrasound: Initial Clinical Assessment.

    Science.gov (United States)

    Choi, Young Jun; Baek, Jung Hwan; Park, Hye Sun; Shim, Woo Hyun; Kim, Tae Yong; Shong, Young Kee; Lee, Jeong Hyun

    2017-04-01

    An initial clinical assessment is described of a new, commercially available, computer-aided diagnosis (CAD) system using artificial intelligence (AI) for thyroid ultrasound, and its performance is evaluated in the diagnosis of malignant thyroid nodules and categorization of nodule characteristics. Patients with thyroid nodules with decisive diagnosis, whether benign or malignant, were consecutively enrolled from November 2015 to February 2016. An experienced radiologist reviewed the ultrasound image characteristics of the thyroid nodules, while another radiologist assessed the same thyroid nodules using the CAD system, providing ultrasound characteristics and a diagnosis of whether nodules were benign or malignant. The diagnostic performance and agreement of US characteristics between the experienced radiologist and the CAD system were compared. In total, 102 thyroid nodules from 89 patients were included; 59 (57.8%) were benign and 43 (42.2%) were malignant. The CAD system showed a similar sensitivity as the experienced radiologist (90.7% vs. 88.4%, p > 0.99), but a lower specificity and a lower area under the receiver operating characteristic (AUROC) curve (specificity: 74.6% vs. 94.9%, p = 0.002; AUROC: 0.83 vs. 0.92, p = 0.021). Classifications of the ultrasound characteristics (composition, orientation, echogenicity, and spongiform) between radiologist and CAD system were in substantial agreement (κ = 0.659, 0.740, 0.733, and 0.658, respectively), while the margin showed a fair agreement (κ = 0.239). The sensitivity of the CAD system using AI for malignant thyroid nodules was as good as that of the experienced radiologist, while specificity and accuracy were lower than those of the experienced radiologist. The CAD system showed an acceptable agreement with the experienced radiologist for characterization of thyroid nodules.

  5. Computer-aided diagnostic system of diffuse liver diseases using scintiscanning, 1. Application of linear discriminant function

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, T; Ogawa, F; Okabe, H; Murakami, K [Kyoto Prefectural Univ. of Medicine (Japan); Yoshida, S

    1976-07-01

    An approach to an automated diagnostic system for diffuse parenchymal diseases of the liver is made based on hepatic scintigraphy and an electronic computer. The findings of hepatic scintigram with /sup 198/Au-colloid were analysed for 7 items, various patterns of hepatic image on anterior view, various patterns of hepatic image on right lateral view, criteria for visualization of bone marrow on anterior view, criteria for visualization of bone marrow on right lateral view, criteria for visualization of spleen on anterior view, degree of splenomegaly, and value of effective hepatic blood flow (KL-value). Each item was subdivided into several categories. Multivariate discriminant analysis was used for differential diagnosis of liver diseases with a dummy variable, based on the 25 categories of the 7 item on 100 abnormal hepato-scintigrams confirmed histologically, and on 20 normal subjects. This study was 90.0% accurate in normal liver, 81.1% accurate in acute hepatitis, 71.1% in inactive chronic hepatitis, 78.2% in active chronic hepatitis, 93.3% in Ko-type of liver cirrhosis, and 77.8% in the Otu-type of liver cirrhosis. The final diagnostic accuracy was 81.7% in all cases for training group. The accuracy of hepatic scintigraphy was 13% and 19% higher than that of laboratory findings in differentiating two groups of liver cirrhosis and two groups of chronic hepatitis respectively. To obtain maximum diagnostic information for discriminating among etiologies, ranges of discriminant function coefficients in these items were compared with in each group of liver diseases. The most useful diagnostic finding were the configurations of the hepatic images on the anterior and the right lateral views. Visualization of the spleen and the degree of splenomegaly were also useful for differentiation in each group of chronic hepatitis and liver cirrhosis.

  6. A Hybrid Computer-aided-diagnosis System for Prediction of Breast Cancer Recurrence (HPBCR Using Optimized Ensemble Learning

    Directory of Open Access Journals (Sweden)

    Mohammad R. Mohebian

    Full Text Available Cancer is a collection of diseases that involves growing abnormal cells with the potential to invade or spread to the body. Breast cancer is the second leading cause of cancer death among women. A method for 5-year breast cancer recurrence prediction is presented in this manuscript. Clinicopathologic characteristics of 579 breast cancer patients (recurrence prevalence of 19.3% were analyzed and discriminative features were selected using statistical feature selection methods. They were further refined by Particle Swarm Optimization (PSO as the inputs of the classification system with ensemble learning (Bagged Decision Tree: BDT. The proper combination of selected categorical features and also the weight (importance of the selected interval-measurement-scale features were identified by the PSO algorithm. The performance of HPBCR (hybrid predictor of breast cancer recurrence was assessed using the holdout and 4-fold cross-validation. Three other classifiers namely as supported vector machines, DT, and multilayer perceptron neural network were used for comparison. The selected features were diagnosis age, tumor size, lymph node involvement ratio, number of involved axillary lymph nodes, progesterone receptor expression, having hormone therapy and type of surgery. The minimum sensitivity, specificity, precision and accuracy of HPBCR were 77%, 93%, 95% and 85%, respectively in the entire cross-validation folds and the hold-out test fold. HPBCR outperformed the other tested classifiers. It showed excellent agreement with the gold standard (i.e. the oncologist opinion after blood tumor marker and imaging tests, and tissue biopsy. This algorithm is thus a promising online tool for the prediction of breast cancer recurrence. Keywords: Breast cancer, Cancer recurrence, Computer-assisted diagnosis, Machine learning, Prognosis

  7. A Hybrid Computer-aided-diagnosis System for Prediction of Breast Cancer Recurrence (HPBCR) Using Optimized Ensemble Learning.

    Science.gov (United States)

    Mohebian, Mohammad R; Marateb, Hamid R; Mansourian, Marjan; Mañanas, Miguel Angel; Mokarian, Fariborz

    2017-01-01

    Cancer is a collection of diseases that involves growing abnormal cells with the potential to invade or spread to the body. Breast cancer is the second leading cause of cancer death among women. A method for 5-year breast cancer recurrence prediction is presented in this manuscript. Clinicopathologic characteristics of 579 breast cancer patients (recurrence prevalence of 19.3%) were analyzed and discriminative features were selected using statistical feature selection methods. They were further refined by Particle Swarm Optimization (PSO) as the inputs of the classification system with ensemble learning (Bagged Decision Tree: BDT). The proper combination of selected categorical features and also the weight (importance) of the selected interval-measurement-scale features were identified by the PSO algorithm. The performance of HPBCR (hybrid predictor of breast cancer recurrence) was assessed using the holdout and 4-fold cross-validation. Three other classifiers namely as supported vector machines, DT, and multilayer perceptron neural network were used for comparison. The selected features were diagnosis age, tumor size, lymph node involvement ratio, number of involved axillary lymph nodes, progesterone receptor expression, having hormone therapy and type of surgery. The minimum sensitivity, specificity, precision and accuracy of HPBCR were 77%, 93%, 95% and 85%, respectively in the entire cross-validation folds and the hold-out test fold. HPBCR outperformed the other tested classifiers. It showed excellent agreement with the gold standard (i.e. the oncologist opinion after blood tumor marker and imaging tests, and tissue biopsy). This algorithm is thus a promising online tool for the prediction of breast cancer recurrence.

  8. Development of a tomographic system adapted to 3D measurement of contaminated wounds based on the Cacao concept (Computer aided collimation Gamma Camera)

    International Nuclear Information System (INIS)

    Douiri, A.

    2002-03-01

    The computer aided collimation gamma camera (CACAO in French) is a gamma camera using a collimator with large holes, a supplementary linear scanning motion during the acquisition and a dedicated reconstruction program taking full account of the source depth. The CACAO system was introduced to improve both the sensitivity and the resolution in nuclear medicine. This thesis focuses on the design of a fast and robust reconstruction algorithm in the CACAO project. We start by an overview of tomographic imaging techniques in nuclear medicine. After modelling the physical CACAO system, we present the complete reconstruction program which involves three steps: 1) shift and sum 2) deconvolution and filtering 3) rotation and sum. The deconvolution is the critical step that decreases the signal to noise ratio of the reconstructed images. We propose a regularized multi-channel algorithm to solve the deconvolution problem. We also present a fast algorithm based on Splines functions and preserving the high quality of the reconstructed images for the shift and the rotation steps. Comparisons of simulated reconstructed images in 2D and 3D for the conventional system (CPHC) and CACAO demonstrate the ability of CACAO system to increase the quality of the SPECT images. Finally, this study concludes with an experimental approach with a pixellated detector conceived for a 3D measurement of contaminated wounds. This experimentation proves the possible advantages of coupling the CACAO project with pixellated detectors. Moreover, a variety of applications could fully benefit from the CACAO system, such as low activity imaging, the use of high-energy gamma isotopes and the visualization of deep organs. Moreover the combination of the CACAO system with a pixels detector may open up further possibilities for the future of nuclear medicine. (author)

  9. An esthetics rehabilitation with computer-aided design/ computer-aided manufacturing technology.

    Science.gov (United States)

    Mazaro, Josá Vitor Quinelli; de Mello, Caroline Cantieri; Zavanelli, Adriana Cristina; Santiago, Joel Ferreira; Amoroso, Andressa Paschoal; Pellizzer, Eduardo Piza

    2014-07-01

    This paper describes a case of a rehabilitation involving Computer Aided Design/Computer Aided Manufacturing (CAD-CAM) system in implant supported and dental supported prostheses using zirconia as framework. The CAD-CAM technology has developed considerably over last few years, becoming a reality in dental practice. Among the widely used systems are the systems based on zirconia which demonstrate important physical and mechanical properties of high strength, adequate fracture toughness, biocompatibility and esthetics, and are indicated for unitary prosthetic restorations and posterior and anterior framework. All the modeling was performed by using CAD-CAM system and prostheses were cemented using resin cement best suited for each situation. The rehabilitation of the maxillary arch using zirconia framework demonstrated satisfactory esthetic and functional results after a 12-month control and revealed no biological and technical complications. This article shows the important of use technology CAD/CAM in the manufacture of dental prosthesis and implant-supported.

  10. Evaluation of a computer-aided detection algorithm for timely diagnosis of small acute intracranial hemorrhage on computed tomography in a critical care environment

    Science.gov (United States)

    Lee, Joon K.; Chan, Tao; Liu, Brent J.; Huang, H. K.

    2009-02-01

    Detection of acute intracranial hemorrhage (AIH) is a primary task in the interpretation of computed tomography (CT) brain scans of patients suffering from acute neurological disturbances or after head trauma. Interpretation can be difficult especially when the lesion is inconspicuous or the reader is inexperienced. We have previously developed a computeraided detection (CAD) algorithm to detect small AIH. One hundred and thirty five small AIH CT studies from the Los Angeles County (LAC) + USC Hospital were identified and matched by age and sex with one hundred and thirty five normal studies. These cases were then processed using our AIH CAD system to evaluate the efficacy and constraints of the algorithm.

  11. Integrated computer-aided design using minicomputers

    Science.gov (United States)

    Storaasli, O. O.

    1980-01-01

    Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM), a highly interactive software, has been implemented on minicomputers at the NASA Langley Research Center. CAD/CAM software integrates many formerly fragmented programs and procedures into one cohesive system; it also includes finite element modeling and analysis, and has been interfaced via a computer network to a relational data base management system and offline plotting devices on mainframe computers. The CAD/CAM software system requires interactive graphics terminals operating at a minimum of 4800 bits/sec transfer rate to a computer. The system is portable and introduces 'interactive graphics', which permits the creation and modification of models interactively. The CAD/CAM system has already produced designs for a large area space platform, a national transonic facility fan blade, and a laminar flow control wind tunnel model. Besides the design/drafting element analysis capability, CAD/CAM provides options to produce an automatic program tooling code to drive a numerically controlled (N/C) machine. Reductions in time for design, engineering, drawing, finite element modeling, and N/C machining will benefit productivity through reduced costs, fewer errors, and a wider range of configuration.

  12. Effectiveness of a computer-aided neuroanatomy program for entry-level physical therapy students: anatomy and clinical examination of the dorsal column-medial lemniscal system.

    Science.gov (United States)

    McKeough, D Michael; Mattern-Baxter, Katrin; Barakatt, Edward

    2010-01-01

    The purpose of this study was to determine if a computer-aided instruction learning module improves students' knowledge of the neuroanatomy/physiology and clinical examination of the dorsal column-medial lemniscal (DCML) system. Sixty-one physical therapy students enrolled in a clinical neurology course in entry-level PT educational programs at two universities participated in the study. Students from University-1 (U1;) had not had a previous neuroanatomy course, while students from University-2 (U2;) had taken a neuroanatomy course in the previous semester. Before and after working with the learning module, students took a paper-and-pencil test on the neuroanatomy/physiology and clinical examination of the DCML system. Kruskal-Wallis one-way ANOVA and Mann-Whitney tests were used to determine if differences existed between neuroanatomy/physiology examination scores and clinical examination scores before and after taking the learning module, and between student groups based on university attended. For students from U1, neuroanatomy/physiology post-test scores improved significantly over pre-test scores (p Neuroanatomy/physiology pre-test scores from U2 were significantly better than those from U1 (p < 0.001); there was no significant difference in post-test scores (p = 0.062). Clinical examination pre-test and post-test scores from U2 were significantly better than those from U1 (p < 0.001). Clinical examination post-test scores improved significantly from the pre-test scores for both U1 (p < 0.001) and U2 (p < 0.001).

  13. Computer-aided detection (CAD) of solid pulmonary nodules in chest x-ray equivalent ultralow dose chest CT - first in-vivo results at dose levels of 0.13 mSv

    Energy Technology Data Exchange (ETDEWEB)

    Messerli, Michael, E-mail: Michael.Messerli@usz.ch [Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen (Switzerland); Kluckert, Thomas; Knitel, Meinhard [Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen (Switzerland); Rengier, Fabian [Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg (Germany); Warschkow, René [Department of Surgery, Cantonal Hospital St. Gallen (Switzerland); Alkadhi, Hatem [Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University Zurich (Switzerland); Leschka, Sebastian [Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen (Switzerland); Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University Zurich (Switzerland); Wildermuth, Simon; Bauer, Ralf W. [Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen (Switzerland)

    2016-12-15

    Highlights: • Computer-aided detection (CAD) of solid pulmonary nodules was compared in 202 patients in standard dose and ultralow dose CT. • The per–nodule sensitivity of CAD was 70% in standard dose CT and 68% in ultralow dose CT. • The per–nodule sensitivity of CAD in standard dose CT was similar to ultralow dose CT in all size subgroups (all p > 0.05). • Adding CAD markings in ultralow dose CT significantly improved the sensitivity of two radiologists from 77% to 88% and from 66% to 79%, respectively. • CAD can serve as an excellent second reader for nodule detection in CT even at dose levels similar to chest X-ray. - Abstract: Objectives: To determine the value of computer-aided detection (CAD) for solid pulmonary nodules in ultralow radiation dose single-energy computed tomography (CT) of the chest using third-generation dual-source CT at 100 kV and fixed tube current at 70 mAs with tin filtration. Methods: 202 consecutive patients undergoing clinically indicated standard dose chest CT (1.8 ± 0.7 mSv) were prospectively included and scanned with an additional ultralow dose CT (0.13 ± 0.01 mSv) in the same session. Standard of reference (SOR) was established by consensus reading of standard dose CT by two radiologists. CAD was performed in standard dose and ultralow dose CT with two different reconstruction kernels. CAD detection rate of nodules was evaluated including subgroups of different nodule sizes (<5, 5–7, >7 mm). Sensitivity was further analysed in multivariable mixed effects logistic regression. Results: The SOR included 279 solid nodules (mean diameter 4.3 ± 3.4 mm, range 1–24 mm). There was no significant difference in per–nodule sensitivity of CAD in standard dose with 70% compared to 68% in ultralow dose CT both overall and in different size subgroups (all p > 0.05). CAD led to a significant increase of sensitivity for both radiologists reading the ultralow dose CT scans (all p < 0.001). In multivariable analysis, the use

  14. Computer-aided detection (CAD) of solid pulmonary nodules in chest x-ray equivalent ultralow dose chest CT - first in-vivo results at dose levels of 0.13 mSv

    International Nuclear Information System (INIS)

    Messerli, Michael; Kluckert, Thomas; Knitel, Meinhard; Rengier, Fabian; Warschkow, René; Alkadhi, Hatem; Leschka, Sebastian; Wildermuth, Simon; Bauer, Ralf W.

    2016-01-01

    Highlights: • Computer-aided detection (CAD) of solid pulmonary nodules was compared in 202 patients in standard dose and ultralow dose CT. • The per–nodule sensitivity of CAD was 70% in standard dose CT and 68% in ultralow dose CT. • The per–nodule sensitivity of CAD in standard dose CT was similar to ultralow dose CT in all size subgroups (all p > 0.05). • Adding CAD markings in ultralow dose CT significantly improved the sensitivity of two radiologists from 77% to 88% and from 66% to 79%, respectively. • CAD can serve as an excellent second reader for nodule detection in CT even at dose levels similar to chest X-ray. - Abstract: Objectives: To determine the value of computer-aided detection (CAD) for solid pulmonary nodules in ultralow radiation dose single-energy computed tomography (CT) of the chest using third-generation dual-source CT at 100 kV and fixed tube current at 70 mAs with tin filtration. Methods: 202 consecutive patients undergoing clinically indicated standard dose chest CT (1.8 ± 0.7 mSv) were prospectively included and scanned with an additional ultralow dose CT (0.13 ± 0.01 mSv) in the same session. Standard of reference (SOR) was established by consensus reading of standard dose CT by two radiologists. CAD was performed in standard dose and ultralow dose CT with two different reconstruction kernels. CAD detection rate of nodules was evaluated including subgroups of different nodule sizes (<5, 5–7, >7 mm). Sensitivity was further analysed in multivariable mixed effects logistic regression. Results: The SOR included 279 solid nodules (mean diameter 4.3 ± 3.4 mm, range 1–24 mm). There was no significant difference in per–nodule sensitivity of CAD in standard dose with 70% compared to 68% in ultralow dose CT both overall and in different size subgroups (all p > 0.05). CAD led to a significant increase of sensitivity for both radiologists reading the ultralow dose CT scans (all p < 0.001). In multivariable analysis, the use

  15. Computer aided safety analysis 1989

    International Nuclear Information System (INIS)

    1990-04-01

    The meeting was conducted in a workshop style, to encourage involvement of all participants during the discussions. Forty-five (45) experts from 19 countries, plus 22 experts from the GDR participated in the meeting. A list of participants can be found at the end of this volume. Forty-two (42) papers were presented and discussed during the meeting. Additionally an open discussion was held on the possible directions of the IAEA programme on Computer Aided Safety Analysis. A summary of the conclusions of these discussions is presented in the publication. The remainder of this proceedings volume comprises the transcript of selected technical papers (22) presented in the meeting. It is the intention of the IAEA that the publication of these proceedings will extend the benefits of the discussions held during the meeting to a larger audience throughout the world. The Technical Committee/Workshop on Computer Aided Safety Analysis was organized by the IAEA in cooperation with the National Board for Safety and Radiological Protection (SAAS) of the German Democratic Republic in Berlin. The purpose of the meeting was to provide an opportunity for discussions on experiences in the use of computer codes used for safety analysis of nuclear power plants. In particular it was intended to provide a forum for exchange of information among experts using computer codes for safety analysis under the Technical Cooperation Programme on Safety of WWER Type Reactors (RER/9/004) and other experts throughout the world. A separate abstract was prepared for each of the 22 selected papers. Refs, figs tabs and pictures

  16. Development and evaluation of a computer-aided diagnostic scheme for lung nodule detection in chest radiographs by means of two-stage nodule enhancement with support vector classification

    International Nuclear Information System (INIS)

    Chen Sheng; Suzuki, Kenji; MacMahon, Heber

    2011-01-01

    Purpose: To develop a computer-aided detection (CADe) scheme for nodules in chest radiographs (CXRs) with a high sensitivity and a low false-positive (FP) rate. Methods: The authors developed a CADe scheme consisting of five major steps, which were developed for improving the overall performance of CADe schemes. First, to segment the lung fields accurately, the authors developed a multisegment active shape model. Then, a two-stage nodule-enhancement technique was developed for improving the conspicuity of nodules. Initial nodule candidates were detected and segmented by using the clustering watershed algorithm. Thirty-one shape-, gray-level-, surface-, and gradient-based features were extracted from each segmented candidate for determining the feature space, including one of the new features based on the Canny edge detector to eliminate a major FP source caused by rib crossings. Finally, a nonlinear support vector machine (SVM) with a Gaussian kernel was employed for classification of the nodule candidates. Results: To evaluate and compare the scheme to other published CADe schemes, the authors used a publicly available database containing 140 nodules in 140 CXRs and 93 normal CXRs. The CADe scheme based on the SVM classifier achieved sensitivities of 78.6% (110/140) and 71.4% (100/140) with averages of 5.0 (1165/233) FPs/image and 2.0 (466/233) FPs/image, respectively, in a leave-one-out cross-validation test, whereas the CADe scheme based on a linear discriminant analysis classifier had a sensitivity of 60.7% (85/140) at an FP rate of 5.0 FPs/image. For nodules classified as ''very subtle'' and ''extremely subtle,'' a sensitivity of 57.1% (24/42) was achieved at an FP rate of 5.0 FPs/image. When the authors used a database developed at the University of Chicago, the sensitivities was 83.3% (40/48) and 77.1% (37/48) at an FP rate of 5.0 (240/48) FPs/image and 2.0 (96/48) FPs /image, respectively. Conclusions: These results compare favorably to those described for

  17. Computer aided method of low voltage power distribution networks protection system against lightning and electromagnetic pulse generated by high altitude nuclear burst

    International Nuclear Information System (INIS)

    Laroubine, J.

    1989-01-01

    The lightning creates an electromagnetic field which produces a slow duration and high energy pulse of current on low voltage power distribution networks. On the other hand an high altitude nuclear burst generates an electromagnetic pulse which causes fast and intense interferences. We describe here the specifications of a passive filter that can reject these interferences. We used a computer aided method of simulation to create a prototype. Experimental results confirm the validity of the model used for simulation [fr

  18. Computer-aided diagnosis in routine mammography

    International Nuclear Information System (INIS)

    Sittek, H.; Perlet, C.; Helmberger, R.; Linsmeier, E.; Kessler, M.; Reiser, M.

    1998-01-01

    Purpose: Computer-aided diagnosis in mammography is a topic many study groups have been concerned with since the first presentation of a system for computer-aided interpretation in 1967. Currently, there is only one system avilable for clinical use in mammography, the CAD-System Image Checker (R2 Technology). The purpose of our prospective study was to evaluate whether the integration of the CAD-system into the routine of a radiological breast diagnosis unit is feasible. Results: After the installation of the CAD-system, 300 patients with 1110 mammograms were included for evaluation in the present study. In 54 of these cases histological examination was indicated due to suspect criteria on conventional mammography. In 39 of 54 cases (72,2%) malignancy could be proven histologically. The CAD-system marked 82,1% of the histologically verified carcinomas correctly 94,3% of all 1797 marks made by the CAD-system indicated normal or benign structures. Routinely performed CAD analysis prolonged patients waiting time by about 15 min because the marks of the CAD system had to be interpreted in addition to the routine diagnostic investigations. Conclusion: Our experience with the use of the CAD-system in daily routine showed that CAD analysis can easily be integrated into a preexisting mammography unit. However, the diagnostic benefit is not yet clearly established. Since the rate of false negative marks by the CAD-system Image Checker is still high, the results of CAD analysis must be checked and corrected by an observer well experienced in mammography reading. (orig.) [de

  19. Effects of three silane primers and five adhesive agents on the bond strength of composite material for a computer-aided design and manufacturing system.

    Science.gov (United States)

    Shinohara, Ayano; Taira, Yohsuke; Sakihara, Michino; Sawase, Takashi

    2018-01-01

    Objective The objective of this study was to evaluate the effects of combinations of silane primers and adhesive agents on the bond strength of a composite block for a computer-aided design and manufacturing system. Material and Methods Three silane primers [Clearfil Ceramic Primer (CP), Super-Bond PZ Primer (PZ), and GC Ceramic Primer II (GP)] were used in conjunction with five adhesive agents [G-Premio Bond (P-Bond), Repair Adhe Adhesive (R-Adhesive), Super-Bond D-Liner Dual (SB-Dual), Super-Bond C&B (SB-Self), and SB-Dual without tributylborane derivative (SB-Light)]. The surface of a composite block (Gradia Block) was ground with silicon carbide paper. After treatment with a silane primer, a adhesive agent was applied to each testing specimen. The specimens were then bonded with a light-curing resin composite. After 24 h, the shear bond strength values were determined and compared using a post hoc test (α=0.05, n=8/group). We also prepared control specimens without primer (No primer) and/or without adhesive agent (No adhesive). Results PZ/SB-Dual and GP/SB-Dual presented the highest bond strength, followed by GP/P-Bond, CP/SB-Dual, CP/R-Adhesive, No primer/SB-Dual, GP/R-Adhesive, CP/P-Bond, No primer/R-Adhesive, PZ/R-Adhesive, CP/SB-Self, PZ/P-Bond, PZ/SB-Self, and GP/SB-Self in descending order of bond strength. No primer/P-Bond, No primer/SB-Self, and all specimens in the SB-Light and No adhesive groups presented the lowest bond strengths. Conclusion A dual-curing adhesive agent (SB-Dual) containing a tributylborane derivative in combination with a silane primer (GP or PZ) presents a greater bond strength between the composite block and the repairing resin composite than the comparators used in the study.

  20. Computer Aided Battery Engineering Consortium

    Energy Technology Data Exchange (ETDEWEB)

    Pesaran, Ahmad

    2016-06-07

    A multi-national lab collaborative team was assembled that includes experts from academia and industry to enhance recently developed Computer-Aided Battery Engineering for Electric Drive Vehicles (CAEBAT)-II battery crush modeling tools and to develop microstructure models for electrode design - both computationally efficient. Task 1. The new Multi-Scale Multi-Domain model framework (GH-MSMD) provides 100x to 1,000x computation speed-up in battery electrochemical/thermal simulation while retaining modularity of particles and electrode-, cell-, and pack-level domains. The increased speed enables direct use of the full model in parameter identification. Task 2. Mechanical-electrochemical-thermal (MECT) models for mechanical abuse simulation were simultaneously coupled, enabling simultaneous modeling of electrochemical reactions during the short circuit, when necessary. The interactions between mechanical failure and battery cell performance were studied, and the flexibility of the model for various batteries structures and loading conditions was improved. Model validation is ongoing to compare with test data from Sandia National Laboratories. The ABDT tool was established in ANSYS. Task 3. Microstructural modeling was conducted to enhance next-generation electrode designs. This 3- year project will validate models for a variety of electrodes, complementing Advanced Battery Research programs. Prototype tools have been developed for electrochemical simulation and geometric reconstruction.

  1. Computer-aided diagnosis and volumetry of pulmonary nodules: current concepts and future perspectives

    International Nuclear Information System (INIS)

    Marten, K.; Rummeny, E.J.; Engelke, C.

    2005-01-01

    For computer-aided detection (CAD) and volumetry of small pulmonary nodules, a number of algorithms have been developed for multislice CT data sets in recent years, with the goal of improving the diagnostic work-up and the follow-up of findings. Recent data show that the detection of small lesions may improve with CAD, suggesting that especially experienced readers may benefit from using CAD systems. This has lead to the recommendation of CAD as a replacement of the second reader in clinical practice. Furthermore, computer-aided volumetry of pulmonary nodules allows a precise determination of nodular growth rates as a prerequisite for a better classification of nodules as benign or malignant. In this article, we review recent developments of CAD and volumetry tools for pulmonary nodules, and address open questions regarding the use of these software tools in clinical routine. (orig.)

  2. Computer-aided engineering of semiconductor integrated circuits

    Science.gov (United States)

    Meindl, J. D.; Dutton, R. W.; Gibbons, J. F.; Helms, C. R.; Plummer, J. D.; Tiller, W. A.; Ho, C. P.; Saraswat, K. C.; Deal, B. E.; Kamins, T. I.

    1980-07-01

    Economical procurement of small quantities of high performance custom integrated circuits for military systems is impeded by inadequate process, device and circuit models that handicap low cost computer aided design. The principal objective of this program is to formulate physical models of fabrication processes, devices and circuits to allow total computer-aided design of custom large-scale integrated circuits. The basic areas under investigation are (1) thermal oxidation, (2) ion implantation and diffusion, (3) chemical vapor deposition of silicon and refractory metal silicides, (4) device simulation and analytic measurements. This report discusses the fourth year of the program.

  3. Pulmonary lobar volumetry using novel volumetric computer-aided diagnosis and computed tomography

    Science.gov (United States)

    Iwano, Shingo; Kitano, Mariko; Matsuo, Keiji; Kawakami, Kenichi; Koike, Wataru; Kishimoto, Mariko; Inoue, Tsutomu; Li, Yuanzhong; Naganawa, Shinji

    2013-01-01

    OBJECTIVES To compare the accuracy of pulmonary lobar volumetry using the conventional number of segments method and novel volumetric computer-aided diagnosis using 3D computed tomography images. METHODS We acquired 50 consecutive preoperative 3D computed tomography examinations for lung tumours reconstructed at 1-mm slice thicknesses. We calculated the lobar volume and the emphysematous lobar volume volumetry computer-aided diagnosis system could more precisely measure lobar volumes than the conventional number of segments method. Because semi-automatic computer-aided diagnosis and automatic computer-aided diagnosis were complementary, in clinical use, it would be more practical to first measure volumes by automatic computer-aided diagnosis, and then use semi-automatic measurements if automatic computer-aided diagnosis failed. PMID:23526418

  4. [Key points for esthetic rehabilitation of anterior teeth using chair-side computer aided design and computer aided manufacture technique].

    Science.gov (United States)

    Yang, J; Feng, H L

    2018-04-09

    With the rapid development of the chair-side computer aided design and computer aided manufacture (CAD/CAM) technology, its accuracy and operability of have been greatly improved in recent years. Chair-side CAD/CAM system may produce all kinds of indirect restorations, and has the advantages of rapid, accurate and stable production. It has become the future development direction of Stomatology. This paper describes the clinical application of the chair-side CAD/CAM technology for anterior aesthetic restorations from the aspects of shade and shape.

  5. Computer-aided control systems for the operation of electrical power networks. Elektronische Leitsysteme fuer Produktion und Energieversorgung. Vortragsreihe der Arbeitsgemeinschaft des VDE-Bezirksvereins Frankfurt am Main vom 9. bis 30. November 1981

    Energy Technology Data Exchange (ETDEWEB)

    Fleck, K

    1981-01-01

    This presentation gives a brief survey on computer-aided operation of medium-voltage networks. By means of the general problem and with the aid of some examples the design of such systems is outlined and the possibilities for instrumentation and control engineering is indicated. The computer systems, which for reasons of availability are mostly redundant, are described in detail. The software by means of which the operating personnel monitors, guides and partly remotely controls the electric grid is explained. To conclude with, a newly designed communication interface between man and machine is mentioned.

  6. Curved planar reformation and optimal path tracing (CROP) method for false positive reduction in computer-aided detection of pulmonary embolism in CTPA

    Science.gov (United States)

    Zhou, Chuan; Chan, Heang-Ping; Guo, Yanhui; Wei, Jun; Chughtai, Aamer; Hadjiiski, Lubomir M.; Sundaram, Baskaran; Patel, Smita; Kuriakose, Jean W.; Kazerooni, Ella A.

    2013-03-01

    The curved planar reformation (CPR) method re-samples the vascular structures along the vessel centerline to generate longitudinal cross-section views. The CPR technique has been commonly used in coronary CTA workstation to facilitate radiologists' visual assessment of coronary diseases, but has not yet been used for pulmonary vessel analysis in CTPA due to the complicated tree structures and the vast network of pulmonary vasculature. In this study, a new curved planar reformation and optimal path tracing (CROP) method was developed to facilitate feature extraction and false positive (FP) reduction and improve our PE detection system. PE candidates are first identified in the segmented pulmonary vessels at prescreening. Based on Dijkstra's algorithm, the optimal path (OP) is traced from the pulmonary trunk bifurcation point to each PE candidate. The traced vessel is then straightened and a reformatted volume is generated using CPR. Eleven new features that characterize the intensity, gradient, and topology are extracted from the PE candidate in the CPR volume and combined with the previously developed 9 features to form a new feature space for FP classification. With IRB approval, CTPA of 59 PE cases were retrospectively collected from our patient files (UM set) and 69 PE cases from the PIOPED II data set with access permission. 595 and 800 PEs were manually marked by experienced radiologists as reference standard for the UM and PIOPED set, respectively. At a test sensitivity of 80%, the average FP rate was improved from 18.9 to 11.9 FPs/case with the new method for the PIOPED set when the UM set was used for training. The FP rate was improved from 22.6 to 14.2 FPs/case for the UM set when the PIOPED set was used for training. The improvement in the free response receiver operating characteristic (FROC) curves was statistically significant (p<0.05) by JAFROC analysis, indicating that the new features extracted from the CROP method are useful for FP reduction.

  7. DEVELOPMENT OF COMPUTER AIDED DESIGN OF CHAIN COUPLING

    Directory of Open Access Journals (Sweden)

    Sergey Aleksandrovich Sergeev

    2015-12-01

    Full Text Available The present paper describes the development stages of computer-aided design of chain couplings. The first stage is the automation of traditional design techniques (intermediate automation. The second integrated automation with the development of automated equipment and production technology, including on the basis of flexible manufacturing systems (high level of automation.

  8. Caesy: A software tool for computer-aided engineering

    Science.gov (United States)

    Wette, Matt

    1993-01-01

    A new software tool, Caesy, is described. This tool provides a strongly typed programming environment for research in the development of algorithms and software for computer-aided control system design. A description of the user language and its implementation as they currently stand are presented along with a description of work in progress and areas of future work.

  9. Software Engineering Techniques for Computer-Aided Learning.

    Science.gov (United States)

    Ibrahim, Bertrand

    1989-01-01

    Describes the process for developing tutorials for computer-aided learning (CAL) using a programing language rather than an authoring system. The workstation used is described, the use of graphics is discussed, the role of a local area network (LAN) is explained, and future plans are discussed. (five references) (LRW)

  10. Computer-aided diagnosis of colonic polyp by CT colonography

    International Nuclear Information System (INIS)

    Yoshida, Hiroyuki

    2007-01-01

    The outcome of National CT Colonography Trial, by American College of Radiology Imaging Network, 2006 (www.acrin.org/6664 protocol), possibly leads to the introduction of colorectal cancer screening in the US because CT colonography (CTCG) has been approved in the health insurance system. This paper describes the outline of computer-aided diagnosis (CAD) of colonic polyp by CTCG, its polyp detectability and future aspects. CTCG essentially derives from the virtual, abdominal 3D CT images and gives as many as about 500 images/patient, in the reading of which CAD support the expert. CAD technology in CTCG is said to have been essentially established in the first half of 2000s, which involves the cleansing of fecal tagging effect, extraction of the colonal wall from the image, detection of suspicious polyp, reduction of false-positive findings and displaying of the detected polyp. The detectability is thought to be at comparable level to expert's. The last displaying is done on the user-interface like Colon CAD Workstation. More efficient expert's reading with CAD, imaging without previous gut cleansing, detection of the flat lesion and further reduction of false-positive are the forthcoming tasks in clinical practice. Significance of CTCG is becoming in realization and its usage with CAD is thought to be more popular in Japan. (R.T.)

  11. CAT -- computer aided testing for resonant inspection

    International Nuclear Information System (INIS)

    Foley, David K.

    1998-01-01

    Application of computer technology relates to inspection and quality control. The computer aided testing (CAT) can be used to analyze various NDT technologies, such as eddy current, ultrasonics, and resonant inspection

  12. Prerequisites for Computer-Aided Cognitive Rehabilitation.

    Science.gov (United States)

    Legrand, Colette

    1989-01-01

    This paper describes computer-aided cognitive rehabilitation for mentally deficient persons. It lists motor, cognitive, emotional, and educational prerequisites to such rehabilitation and states advantages and disadvantages in using the prerequisites. (JDD)

  13. Applicability of computer-aided comprehensive tool (LINDA: LINeament Detection and Analysis) and shaded digital elevation model for characterizing and interpreting morphotectonic features from lineaments

    Science.gov (United States)

    Masoud, Alaa; Koike, Katsuaki

    2017-09-01

    Detection and analysis of linear features related to surface and subsurface structures have been deemed necessary in natural resource exploration and earth surface instability assessment. Subjectivity in choosing control parameters required in conventional methods of lineament detection may cause unreliable results. To reduce this ambiguity, we developed LINDA (LINeament Detection and Analysis), an integrated tool with graphical user interface in Visual Basic. This tool automates processes of detection and analysis of linear features from grid data of topography (digital elevation model; DEM), gravity and magnetic surfaces, as well as data from remote sensing imagery. A simple interface with five display windows forms a user-friendly interactive environment. The interface facilitates grid data shading, detection and grouping of segments, lineament analyses for calculating strike and dip and estimating fault type, and interactive viewing of lineament geometry. Density maps of the center and intersection points of linear features (segments and lineaments) are also included. A systematic analysis of test DEMs and Landsat 7 ETM+ imagery datasets in the North and South Eastern Deserts of Egypt is implemented to demonstrate the capability of LINDA and correct use of its functions. Linear features from the DEM are superior to those from the imagery in terms of frequency, but both linear features agree with location and direction of V-shaped valleys and dykes and reference fault data. Through the case studies, LINDA applicability is demonstrated to highlight dominant structural trends, which can aid understanding of geodynamic frameworks in any region.

  14. Remote handling prospects. Computer aided remote handling

    International Nuclear Information System (INIS)

    Vertut, J.

    1984-01-01

    Mechanical manipulators, electrical control manipulators and computer aided manipulators were successively developed. The aim of computer aided manipulators is the realization of complex or tricky job in adverse environment but man is required for non routine work or for situation in evolution. French effort is developed in the frame of the project automation and advanced robotics and new problems have to be solved particularly at the interface man/machine [fr

  15. Microwave processing of a dental ceramic used in computer-aided design/computer-aided manufacturing.

    Science.gov (United States)

    Pendola, Martin; Saha, Subrata

    2015-01-01

    Because of their favorable mechanical properties and natural esthetics, ceramics are widely used in restorative dentistry. The conventional ceramic sintering process required for their use is usually slow, however, and the equipment has an elevated energy consumption. Sintering processes that use microwaves have several advantages compared to regular sintering: shorter processing times, lower energy consumption, and the capacity for volumetric heating. The objective of this study was to test the mechanical properties of a dental ceramic used in computer-aided design/computer-aided manufacturing (CAD/CAM) after the specimens were processed with microwave hybrid sintering. Density, hardness, and bending strength were measured. When ceramic specimens were sintered with microwaves, the processing times were reduced and protocols were simplified. Hardness was improved almost 20% compared to regular sintering, and flexural strength measurements suggested that specimens were approximately 50% stronger than specimens sintered in a conventional system. Microwave hybrid sintering may preserve or improve the mechanical properties of dental ceramics designed for CAD/CAM processing systems, reducing processing and waiting times.

  16. Intelligent computer-aided training and tutoring

    Science.gov (United States)

    Loftin, R. Bowen; Savely, Robert T.

    1991-01-01

    Specific autonomous training systems based on artificial intelligence technology for use by NASA astronauts, flight controllers, and ground-based support personnel that demonstrate an alternative to current training systems are described. In addition to these specific systems, the evolution of a general architecture for autonomous intelligent training systems that integrates many of the features of traditional training programs with artificial intelligence techniques is presented. These Intelligent Computer-Aided Training (ICAT) systems would provide, for the trainee, much of the same experience that could be gained from the best on-the-job training. By integrating domain expertise with a knowledge of appropriate training methods, an ICAT session should duplicate, as closely as possible, the trainee undergoing on-the-job training in the task environment, benefitting from the full attention of a task expert who is also an expert trainer. Thus, the philosophy of the ICAT system is to emulate the behavior of an experienced individual devoting his full time and attention to the training of a novice - proposing challenging training scenarios, monitoring and evaluating the actions of the trainee, providing meaningful comments in response to trainee errors, responding to trainee requests for information, giving hints (if appropriate), and remembering the strengths and weaknesses displayed by the trainee so that appropriate future exercises can be designed.

  17. Comparison of sensitivity and reading time for the use of computer-aided detection (CAD) of pulmonary nodules at MDCT as concurrent or second reader

    International Nuclear Information System (INIS)

    Beyer, F.; Zierott, L.; Juergens, K.U.; Heindel, W.; Fallenberg, E.M.; Stoeckel, J.; Wormanns, D.

    2007-01-01

    The purpose of this study was to compare sensitivity for detection of pulmonary nodules in MDCT scans and reading time of radiologists when using CAD as the second reader (SR) respectively concurrent reader (CR). Four radiologists analyzed 50 chest MDCT scans chosen from clinical routine two times and marked all detected pulmonary nodules: first with CAD as CR (display of CAD results immediately in the reading session) and later (median 14 weeks) with CAD as SR (display of CAD markers after completion of first reading without CAD). A Siemens LungCAD prototype was used. Sensitivities for detection of nodules and reading times were recorded. Sensitivity of reading with CAD as SR was significantly higher than reading without CAD (p < 0.001) and C