• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2001.07a
• /
• pp.283-285
• /
• 2001

In this paper, a new lateral insulated gate bipolar transistor (LIGBT) is proposed to improve the latch-up performance without current path underneath the n+ cathode region. The improvement of latch-up performance is verified using the two-dimensional simulator MEDICI and the simulation results on the latch-up current density are 3.12${\times}$10$\^$-4/ A/$\mu\textrm{m}$ for the proposed LIGBT and 0.94${\times}$10$\^$-4/ A/$\mu\textrm{m}$ for the conventional LIGBT. The proposed SOI LIGBT exhibits 3 times larger latch-up capability than the conventional SOI LIGBT.

• The Journal of Advanced Prosthodontics
• /
• v.9 no.6
• /
• pp.486-495
• /
• 2017

The wide use of chairside CAD/CAM restorations has increased the diversity of the restorative material. For the practitioner, the selection of the appropriate material is difficult amongst the variety offered by the market. Information on the characteristics of the products can be difficult to assess due to the lack of up-to-date classification and the lack of reliability of manufacturer's advertising. The purpose of this article is to structure the data on restorative materials provided by various sources in order for the practitioner to choose the product most suited to the clinical situation. The objective is to classify chairside CAD/CAM materials and to define their characteristics and indications.

• Journal of Korean Critical Care Nursing
• /
• v.4 no.1
• /
• pp.1-10
• /
• 2011

Purpose: The study was conducted to find out clinical characteristics for coronary artery disease patients with diabetes mellitus. Methods: We retrospectively reviewed the electronic medical records which included the data of 6,792 patients, who had been diagnosed coronary artery disease (CAD) such as angina or acute myocardial infarction and admitted to a university hospital in Seoul from January, 2005 to November, 2010. Results: Of the 6,792 patients, 43% had been diagnosed diabetes as comorbidity. The CAD patients with diabetes had lower left ventricular ejection fraction, stayed longer at hospital, and spent on more time from the first symptom to hospital visit than those without diabetes. In addition, they were more likely to have multi vessel coronary artery disease. Conclusion: The CAD patients with diabetes lay on the various factors which can make more worsen condition. Hence, we need to pay attention to specialized nursing care and patient education for the CAD patients with diabetes.

• Proceedings of the KSR Conference
• /
• 2008.06a
• /
• pp.139-142
• /
• 2008

Construction Management by using 4D CAD system analyzes operations information based on 3D and 4D objects. But it is difficult to provide a variety of documents linked by 4D objects in a lump from 4D CAD system based on visual object, and to get an optimal decision-making information to conduct business. Therefore, it is necessary to construct effective construction information management systems and to organize integrated information through linking non-objects to objects. This study suggests methodologies of effective construction management for railway facilities through building of framework for practical application and methodologies to link 4D objects to IETM documents. Accordingly, it is possible to establish a systematic decision-making for an effective construction management of railway facilities, and this provide integrated methodology for linking non-objects to objects.

• 한국기계연구소 소보
• /
• s.19
• /
• pp.149-154
• /
• 1989

Generally Cam-Follower systems consist of two elements: Cam is for rotating motion and follower for reciprocating motion. Depending on the shape of cam and type of follower, the motion of cam-follower system is determined. Thus design process and analysis process must be well defined. The design process means to find the coordinates of cam shape which can be defined the given motion of follower and the analysis process means to determine the motion curve of follower corresponding to the given cam based on the dimensions of a cam-follower system. This paper consists of two parts: One is development of a numerical method for design and analysis of cam-follower systems, the other is for development of a CAD program and its application. As the first part of the paper, an iterative contact method is proposed. This method can calculate the contact points between cam and roller and determine their contact angles iteratively. The second part of the paper presents the structure of a CAD program and its availability to the industrial applications.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2007.04a
• /
• pp.357-360
• /
• 2007

In the area of domestic construction industry, recently, standardization of construction. globalization of constructional and a building information arc required to advance increase productivity, shorten the term of works and reduce the cost of construction. The objective of this is to offer basic data of process new thesis and development for automated building equipment design system based on 3D CAD building information. This study contribute the development of automated Building equipment design system based on 3D which helps to conduct the equipment design handily and quickly.

• Korean Journal of Computational Design and Engineering
• /
• v.11 no.6
• /
• pp.422-428
• /
• 2006

In this paper, an NC data optimization approach for enhancing 5-axis machining speed is presented. It is usual to use expensive commercial CAD/CAM programs for NC data of 5-axis machining, since it needs very large calculations for optimal tool positioning and orientation, tool path planning, and collision-free tool path generation. Since commercial CAD/CAM systems have similar functions and efficiency based on common algorithms of reliable theories, they do not have their own unique features for machining speed and efficiency. In other words, most commercial CAD/CAM systems consider only the characteristics of part geometry to be machined, which means that they generate almost the same NC data if the part to be machined is the same, even though different machines are used for the pin. A new approach is proposed for optimizing NC data of 5-axis machining, which is based on the characteristics of the machine to be operated. As a result, the speed of 5-axis machining can increase without losing machining accuracy and surface quality.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.16 no.2
• /
• pp.259-266
• /
• 1992

For CAD/CAPP integration, part information on not only geometry but also machining characteristics should be delivered and commonly used between designers and process planners. In this study, the machining features, as linking factors of the integration, are represented as the combination of functional features and atomic features and grouped into a hierarchical database. And the feature based modelling approach is used by generating information on the machining features in design stage. These features are drawn by analyzing real decision rules of process planners. The database using the machining features is built and used for application modules of process planning, operation planning and standard time estimation.

• International journal of advanced smart convergence
• /
• v.12 no.4
• /
• pp.217-223
• /
• 2023

In this study, we compared the VacCAD and VacTran, commercial vacuum simulators, to investigate the simulation applicability and efficiency as vacuum simulation software. It was verified on reliability and simplicity of simulation modelling, and characteristics of the pump combinations, pumping down curves, and employed vacuum materials. First, usability of simulation schematics was estimated through the modeling tools and the overall simulation characteristics of each simulator were compared to evaluate the applicability in practice. Simulation reliability of each simulator was also probed by comparing the pumping performance characteristics of commercial high vacuum system models. In addition, the degree of tolerances on both simulators was also evaluated through pumping down analysis considering outgassing effect due to chamber material variations. The higher effectiveness and expediency of VacCAD than VacTran has been presented, and it was also expected that the utilization of VacTan in vacuum applications to be increased due to the higher availability of modelling variations.

• Radiation Oncology Journal
• /
• v.32 no.3
• /
• pp.116-124
• /
• 2014

Purpose: 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. Materials and Methods: Sixty-seven treatment-$na{\ddot{i}}ve$ 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. Results: 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. Conclusion: 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.