• Korean Journal of Computational Design and Engineering
• /
• v.4 no.1
• /
• pp.43-51
• /
• 1999

Producing the relevant information (features) from the CAD models of CAM, called feature recognition or extraction, is the essential stage for the integration of CAD and CAM. Most feature recognition methods, however, have problems in the recognition of intersecting features because they do not handle the intersection geometry properly. In this paper, we propose a machining feature recognition algorithm, which has a solid model consisting of orthogonal primitives as input. The algorithm calculates candidate features and constitutes the Intersection Geometry Matrix which is necessary to represent the spatial relation of candidate features. Finally, it recognizes machining features from the proposed candidate features dividing and growing systems using half space and Boolean operation. The algorithm has the following characteristics: Though the geometry of part is complex due to the intersections of design primitives, it can recognize the necessary machining features. In addition, it creates the Maximal Feature Volumes independent of the machining sequences at the feature recognition stage so that it can easily accommodate the change of decision criteria of machining orders.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2000.11a
• /
• pp.267-271
• /
• 2000

A part definition must not only provide shape information of a nominal part but also contain non-shape information such as tolerances, surface roughness and material attributes. Although machining features are useful for suitable shape information for process reasoning in the CAPP, they need to be integrated with tolerance information for effective process planning. We develop the tolerance modeler that efficiently integrates machining features with tolerance information for feature-based CAPP It is based on the association of machining features, tolerance features. and tolerances Tolerance features, where tolerances are assigned, are classified into two types; one is the face that is a topological entity on a solid model and the other is the functional geometry that is not referenced to topological entities. The functional geometry is represented by using machining features All the data for representing tolerance information with machining features are stored completely and unambiguously in the independent tolerance structure. The developed tolerance modeler is implemented as a module of a comprehensive feature-based CAPP system.

• Proceedings of the IEEK Conference
• /
• 2002.06d
• /
• pp.57-60
• /
• 2002

Facial features are often used for human computer interface(HCI). This paper proposes a method to detect facial features using color and facial geometry information. Face region is first extracted by using color information, and then the pupils are detected by applying a separability filter and facial geometry constraints. Mouth is also extracted from Cr(coded red) component. Experimental results shows that the proposed detection method is robust to a wide range of facial variation in position, scale, color and gaze.

• Journal for History of Mathematics
• /
• v.31 no.6
• /
• pp.291-313
• /
• 2018

This study aims to analyze Pardies' ${\ll}$Elements of geometry${\gg}$. This book is very interesting from the perspectives of mathematical history as well as of mathematical education. Because it was used for teaching Kangxi emperor geometry in the Qing Dynasty in China instead of Euclid's which was considered as too difficult to study geometry. It is expected that this book suggests historical and educational implications because it appeared in the context of instruction of geometry in the seventeenth century of mathematical history. This study includes the analyses on the contents of Pardies' ${\ll}$Elements of geometry${\gg}$, the author's advice for geometry learning, several geometrical features, and some features from the view of elementary school mathematics, of which the latter two contain the comparisons with other authors' as well as school mathematics. Moreover, some didactical implications were induced based on the results of the study.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.14 no.4
• /
• pp.506-511
• /
• 2004

Biometrics is getting more and more attention in recent years for security and other concerns. So far, only fingerprint recognition has seen limited success for on-line security check, since other biometrics verification and identification systems require more complicated and expensive acquisition interfaces and recognition processes. Hand-Geometry has been used for biometric verification and identification because of its acquisition convenience and good performance for verification and identification performance. Hence, it can be a good candidate for online checks. Therefore, this paper proposes a Hand-Geometry recognition system based on geometrical features of hand. From anatomical point of view, human hand can be characterized by its length, width, thickness, geometrical composition, shapes of the palm, and shape and geometry of the fingers. This paper proposes thirty relevant features for a Hand-Geometry recognition system. However, during experimentation, it was discovered that length measured from the tip of the finger was not a reliable feature. Hence, we propose a new technique based on Genetic Algorithm for extraction of the center of nail bottom, in order to use it for the length feature.

• Journal of Information Science Theory and Practice
• /
• v.7 no.2
• /
• pp.32-39
• /
• 2019

A convolutional neural network (CNN) has been widely used in facial expression recognition (FER) because it can automatically learn discriminative appearance features from an expression image. To make full use of its discriminating capability, this paper suggests a simple but effective method for CNN based FER. Specifically, instead of an original expression image that contains facial appearance only, the expression image with facial geometry visualization is used as input to CNN. In this way, geometric and appearance features could be simultaneously learned, making CNN more discriminative for FER. A simple CNN extension is also presented in this paper, aiming to utilize geometric expression change derived from an expression image sequence. Experimental results on two public datasets (CK+ and MMI) show that CNN using facial geometry visualization clearly outperforms the conventional CNN using facial appearance only.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.26 no.1
• /
• pp.48-54
• /
• 2002

A part definition must not only provide shape information of a nominal part but also contain non-shape information such as tolerances, surface roughness and material specifications. Although machining features are useful for suitable shape information fur process reasoning in CAPP, they need to be integrated with tolerance information for effective process planning. We develop a tolerance modeler that efficiently integrates the machining features with the tolerance information fur feature-based CAPP. It is based on the association of machining features, tolerance features, and tolerances. The tolerance features in this study, where tolerances are assigned, are classified into two types; one type is a face that is a topological entity on a solid model and the other type is a functional geometry that is not referenced to topological entities. The (unctional geometry is represented by using machining features. All the data fur representing the tolerance information are stored completely and unambiguously in an independent tolerance data structure. The developed tolerance modeler is implemented as a module of a comprehensive feature-based CAPP system.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1994.10a
• /
• pp.737-742
• /
• 1994

In this paper , we propose an incremental approach for recognizing a class of machining features from a featurebased design model as a part design proceeds, utilizing various information such as nominal geometry, design intents, and design feature characteristics. The proposed apptroach can handle complex intersecting features and protrusion features designed on oblique faces. The class of recognized volumetric machining features can be expressed as Material Removal Shape Element Volumes (MRSEVs), a PDES/STEP-based library of machining features.

• Journal of the Korean School Mathematics Society
• /
• v.6 no.2
• /
• pp.39-53
• /
• 2003

We study the dynamic geometry software suitable for the Internet Environment. First, we look into the necessity of dynamic geometry software and compare the functions and the features of commercial softwares, GSP, Cabri and Cinderella. Secondly, we introduce the process of development and the structure of the new software DRC(Digital Ruler and Compass) designed by authors and discuss the learning program with DRC and Internet, and view the upgrade of the software in the future.

• The Journal of the Korea Contents Association
• /
• v.5 no.2
• /
• pp.199-205
• /
• 2005

In this paper, we present a face detection algorithm which uses the features of color and Geometry of faces and hairs appeared in images. after candidate area detection using color features, background areas are removed by the deviation of luminance in each of candidate areas. And then, final face area is detected using feature of geometry between face and hair. Performance of the presented algorithm is evaluated by detection rate test. The test result showed high detection rate.