• Journal of the Korean Data and Information Science Society
• /
• 제19권3호
• /
• pp.735-749
• /
• 2008

This article suggests application of logit model for analysis of multicategory responses. Referring to the reference category, characteristic of each category is obtained from analysis of polytomous logit model. With National Pension data it is illustrated that application of logit model helps it possible to find significant factors which may not be found only with polytomous logit model. Application of the logit model is done by reducing the number of categories. Categories are grouped into the former and the latter group according to reference category. Extra finding of significant factor was possible from logistic regression analysis for the two groups after removing the reference category. It is expected that this application would be helpful for finding information and characteristics on ordered multicategory responses where the proportional odds model does not fit.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 춘계학술대회논문집C
• /
• pp.235-239
• /
• 2001

Finding intersection point between a surface and a line is one of major problem in CAD/CAM. The intersection point could be found in an exact form or with numerical method. In this paper, the exact solution of the intersection point between a ruled surface which is generated by the movement of an endmill and the z-direction vector is presented. The cutter swept surface which is a ruled surface and the Z-direction vector are represented with parametric equations. With the nature of parametric equations, the geometric properties at the intersection point are easily acquired.

• 한국공작기계학회논문집
• /
• 제12권2호
• /
• pp.31-36
• /
• 2003

Electronic or measuring instruments equipped with aspherical lens have recently been used since aspherical lens is more effective than spherical one. for the mass production of aspherical lenses, specific molds with precisely machined cores should be prepared. Some researches on the aspherical lens machining have been carried out to date. However, ultra-precise finding of aspherical or mold core has not been fully studied. In this study, the ultra-precise grinding and evaluating system were established to investigate the finding characteristics of aspherical lenses. Unlike conventional grinding process, since a highly-precise lathe were operated in a clean room without vibration the experimental results can be very useful for further studies on ultra-precise grinding process.

• 공학교육연구
• /
• 제13권5호
• /
• pp.72-75
• /
• 2010

Design subjects have become popular in the engineering education. In these subjects, an active learning skill was introduced to students. Students have to decide a theme and the way how to study it and to find answers by themselves. This learning method was developed in the early year courses in the University of Tokushima. The common learning curriculum among whole university adopted this design subjects from 2005 of the school year and eleven more new subjects started. "Roots finding" is one of them and the objectives are to gain abilities of self-study through the research on a particular subject, and make report then presenting them. Self-learning ability, research ability and presentation skills were enhanced through this subject.

• 비파괴검사학회지
• /
• 제26권6호
• /
• pp.411-416
• /
• 2006

The critical subject of transverse crack detection in a rail head is treated in this paper. Conventional bulk wave ultrasonic techniques oftenfail because of shelling and other surface imperfections that shield the defects that lie below the shelling. A guided wave inspection technique is introduced here that can send ultrasonic energy along the rail under the shelling with a capability of finding the deleterious transverse crack defects. Dispersion curves are generated via a semi analytical finite element technique along with a hybrid guided wave finite element technique to explore the most suitable modes and frequencies for finding these defects. Sensor design and experimental feasibility experiments are also reported.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2002년도 춘계학술대회 논문집
• /
• pp.3-8
• /
• 2002

An intelligent polishing robot automation system is developed. Automatic Tool Change System(A.T.C.), Tool Posture Angle Control, and Robot Program for Polishing Application are developed and integrated into a robotic system that consists of a robot, pneumatic finding tool, and finding abrasives (papers and special films). A.T.C. is specifically designed to exchange whole grinding tool set for complete unmanned operation. Tool Posture Angle Control is developed to give a certain skew angle rather than right angle to tools on the surface for best finishing results. A.T.C. and Tool Posture Angle Control is controlled by a PC and the robot controller. Also, there have been some considerations on enhancing the performance of the system. Some elastic material is inserted between the grinding pad and the holder for better grinding contact. The robot path data is generated automatically from the NC data of previous machining process.

• 기술혁신연구
• /
• 제15권2호
• /
• pp.41-59
• /
• 2007

This paper analyzes interactive activities of foreign R&D centers operating in Korea. Interactive activities refer to collaborative R&D activities, R&D outsourcing, and formation of communities between foreign R&D centers and Korean firms and institutions. Active interactions between foreign R&D centers and their Korean partners (Korean firms and universities, research institutes etc.) are essential in promoting spillover effects from foreign R&D centers. Using the survey of 76 foreign R&D centers operating in Korea, this paper found the intensity of interplay between foreign R&D centers and the Korean firms and institutions was not so high. And the partners of foreign R&D centers with the mission of finding new technologies in Korea are mainly customers rather than universities and research institutes. This result is markedly different from previous studies focused on the cases of western countries, where the partners of foreign R&D centers that have the mission of finding new technologies were mainly local universities and research institutes.

• 한국임상수의학회지
• /
• 제16권1호
• /
• pp.199-202
• /
• 1999

In a 10-year old mixed dog, a $10{\times}10{\times}4$ cm mass was palpated around the left caudal thoracic mammary gland with abdomen expension. In hormonal assay, serum concentrate of progesterone was 0 pg/ml and serum concentrate of estradiol was 66.7 pg/ml. Radiological finding of the mammary gland showed higher density than that of soft tissue and ultrasonographic finding showed inhomogeneous in echogenicity. Light microscopic view of mammary gland showed neoplastic hyperplasia of epithelial and myoepithelial cells and showed some metaplastic lesion of these cells to cartilage or bone tissues with metastasis to the lung. This case was diagnosed as malignant mixed mammary tumor.

• Journal of Chest Surgery
• /
• 제9권2호
• /
• pp.311-314
• /
• 1976

This is a report of leiomyoma in the esophagus. patient had suffered from mild intermittent dysphagia on eating without any other complaints. This complaint had been going for 45 days, but was not progressed. The esophagogram revealed an ovoid walnut-sized smooth filling defect in the midportion of the esophagus. The mucosal folds of the esophagus were not destroyed. A benign intramural tumor of the esophagus, such as leiomyoma, was suspected with X-ray finding and clinical features. On Aug. 13, 1976 a thoracotomy was performed at right 4th intercostal space. A firm, irregular shaped mass in the wall of the esophagus was enucleated by blunt dissection without any injury of the mucosa of the esophagus. The diagnosis of leiomyoma was confirmed with histopathological finding. Postoperative course was uneventful.

• 대한수학교육학회지:학교수학
• /
• 제4권3호
• /
• pp.361-373
• /
• 2002

In this paper, a series of tasks related on polygonal numbers and pyramidal numbers are suggested for using them as teaching unit materials for teaching and learning of sequences in junior high school mathematics. Especially, finding n-th term in those seque-nces, relations among polygonal numbers, and relations among Pyramidal numbers are focused on. A series of tasks related on polygonal numbers and pyramidal numbers have three math-eucational values. First, they have a value as natural materials for teaching and teaming of finding nth term of original sequences using pro-gression of differences. Second, they have a value as materials for teaching and learning of mathematical thinking such as general-ization, analogy, etc. Third, they have a value as materials for teaching and learning of algebraic operation, proof, and connecting mathematical knowledges.