• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1299-1302
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• 2005

Current mechanical devices are trending toward being a small size, high speedy, automation. For performing these functions, machinery elements organizing a machine should be designed exactly. Cams have high confidence and economics in ablility to transmit a motion. Accordingly, A cam mechanism is very important for processing the machine automatically. This paper introduce an inverse cam mechanism. A square shaped cam which cannot be commonly analyzed is designed and manufactured by using the NURBS interpolation algorithm. The objective of this paper is to develop a computer-aided design program. In this paper, a displacement curve of oscillating motion inverse cam mechanism with square shaped follower is analyzed. The data is redistibuted by the NURBS algorithm. A cam shape is designed by the instant velocity center method, and simulated to verify the validity of the operation state.

• 한국정밀공학회지
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• 제19권8호
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• pp.47-54
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• 2002

A barrel cam is used as a very important part of an index drive unit. The index drive unit must have an intermittent-rotational motion. The barrel typed cam and roller gear mechanism has the advantages of high reliability to perform a prescribed motion of a follower. This paper proposes a new method for the shape design of the barrel cam and also a CAD program is developed by using the proposed method. As defined in this paper, the relative velocity method for the shape design calculates the relative velocity of the follower versus cam at a center of roller, and then determines a contact point by using the geometric relationships and the kinematic constraints, where the direction of the relative velocity must be parallel to a common tangential line at the contact point of two independent bodies, i.e. the cam and the follower Then, the shape of the cam is defined by the coordinate transformation of the trace of the contact points. This paper presents two examples for the shape design of the barrel cam in order to prove the accuracy of the proposed methods.

• The Journal of Advanced Prosthodontics
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• 제9권5호
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• pp.402-408
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• 2017

PURPOSE. The goal of this study was to compare the adhesion of Candida albicans to the surfaces of CAD/CAM and conventionally fabricated complete denture bases. MATERIALS AND METHODS. Twenty discs of acrylic resin poly (methyl methacrylate) were fabricated with CAD/CAM and conventional procedures (heat-polymerized acrylic resin). The specimens were divided into two groups: 10 discs were fabricated using the CAD/CAM procedure (Wieland Digital Denture Ivoclar Vivadent), and 10 discs were fabricated using a conventional flasking and pressure-pack technique. Candida colonization was performed on all the specimens using four Candida albicans isolates. The difference in Candida albicans adhesion on the discs was evaluated. The number of adherent yeast cells was calculated by the colony-forming units (CFU) and by Fluorescence microscopy. RESULTS. There was a significant difference in the adhesion of Candida albicans to the complete denture bases created with CAD/CAM and the adhesion to those created with the conventional procedure. The CAD/CAM denture bases exhibited less adhesion of Candida albicans than did the denture bases created with the conventional procedure (P<.05). CONCLUSION. The CAD/CAM procedure for fabricating complete dentures showed promising potential for reducing the adherence of Candida to the denture base surface. Clinical Implications. Complete dentures made with the CAD/CAM procedure might decrease the incidence of denture stomatitis compared with conventional dentures.

• 대한치과기공학회지
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• 제33권3호
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• pp.247-256
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• 2011

Purpose: The purpose of this survey research was to investigate the Perception level of CAD/CAM of dental techique. Methods: This survey was carried out in the metropolitan areas of the cities of Daegu and Gyeong-buk. Surveys were filled out by consenting dental technicians. Statistical analysis was done using the Statistical Package for Social Sciences (SPSS) version 17.0 for Windows. As for the analysis methods, the study used the frequency analysis, Ttest, F-test. Results: Perception of CAD/CAM showed differences in General characteristics associated with education level, monthly salary. Perception of CAD/CAM showed differences in professional characteristics associated with working area, working part. Perception of CAD/CAM showed differences in understanding of CAD/CAM associated with CAD/CAM operating experience, CAD/CAM educational experience. Conclusion: In order to improve the Perception level of CAD/CAM of dental technician, A variety education and follow-up research is need.

• Journal of Photoscience
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• 제12권3호
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• pp.123-127
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• 2005

The polyclonal antibody was generated against the peptide fragment of 62 amino acid residues (D 181-T242) near the COOH-terminal region of the extracellular domain of epithelial-cell adhesion molecule (Ep-CAM) and shown to be able to recognize Ep-CAM in competitive ELISA. Then, sulforhodamine 101 acid chloride (so called Texas red), a fluorescence dye, was conjugated to the affinity-purified anti-Ep-CAM antibody utilizing the reaction between the aliphatic amines of antibody and the sulfonyl chloride of Texas red. The molar ratio of Texas red to antibody was estimated to be approximately 1.86 by measuring optical densities at 280 nm and 596 nm, implying that the two molecules of Texas red at most were conjugated to antibody. The anti-Ep-CAM antibody-Texas red conjugate was then used for immunohistochemistry of CT-26 murine colon carcinoma cells. Based upon the fluorescence microscope images, anti-Ep-CAM antibody is able to deliver Texas red specifically to the surface of CT-26 cells on which Ep-CAM was actively expressed. This result indicates that anti-Ep-CAM antibody could be useful for the tissue-specific delivery of photosensitizers via antigen-antibody interaction.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.529-533
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• 1996

Recently, manufacturing industries are doing their best to increase productivity and to reduce production time. One of tile efforts is to develop user-friendly and effective CAM systems. For this purpose, a CAM system for turning was developed. In the developed system. user interacts with tile CAM system using graphical user interface (GUI) and manufacturing support functions to make NC programs effectively. Manufacturing support functions include cycle decoder. interference check be ween tool and workpicce. bar turning without air cut and dynamic/wireframe simulation. In the cycle decoder. basic options are provided to novices for their convenience. and advanced options are provided to help expert to modify the program using their knowledge. Interference check has been nil issue in tile CAM system for tuning. In this paper. when a user selects a tool. interference check between selected tools and workpieces is done automatically. Moreover. remaining shapes are calculated automatically. Then, tile CAM system requests user to input all additional tool and generates NC codes to cut tile remaining shapes. In bar turning of forged raw material, air cut should be prevented for effective machining. For this purpose, a new algorithm for bar turning was developed. Dynamic and wireframe simulation was used to verify the generated NC code.

• 혜화의학회지
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• 제20권2호
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• pp.141-153
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• 2012

Nowadays, the humankind's lives are affluent enough and the modern medical cure systems have made the humans' lives much longer. In spite of the modern medical development, the chronic & regressive diseases are rapidly increasing ironically. In this regards, many countries endeavoring to rely on the traditional or CAM instead of Conventional and Modern Medicines. The late Steve Jobs who sought for the natural therapy for his pancreatic cancer was one representative example. Every countries are investing huge amount of money to become the leader in the CAM market. Moreover, by preoccupying the world-wide standards, each country is trying to grab the market monopoliy. In this thesis, I examined several coutries' CAM markets and their CAM development strategies. These strategies should be considered for the KTM development Strategy. Fortunately, KTM has doing the main role in the Korean CAM development strategy. But to become the world leader in CAM market, the governmental committee should be established and the Financial Investment and Aid Program should be followed. It is very important to obtain the world standards. To do so, the R&D capability should be enhanced also. The world trends in CAM should be scrutinized and the Government Agency - Scholartic Group - Research institute have to cooperate for the same target.

• 한국기계연구소 소보
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• 통권19호
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• pp.155-161
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• 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 for 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 second part of the paper, the structure of a CAD program is introduced. Four data files are used in the program where the design process and the analysis process are carried out interactively to en hence its availability to the industrial applications. The first part of the paper 'presents the iterative contact method which can determine the contact points and their angles between cam and roller.

• 대한치과기공학회지
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• 제37권4호
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• pp.271-284
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• 2015

Purpose: The purpose of this study was to examine the usage of CAD/CAM, which is one of dental technologist duties, in an effort to look for any possible changes in the usage of CAD/CAM. It's specifically meant to compare the results of this study with those of Lee Jong-do, Park Kwang-Sig(2011)'s study in March, 2011, to determine if there were any changes over the past four years. The selected variables that were investigated were the ownership of CAD/CAM, awareness of it, the route of acquiring the first information on it, the merits and demerits of its usage, usage experience and educational experience about it. Methods: An online survey was conducted on the dental technologists who worked in urban communities including metropolitan cities to find out the usage of CAD/CAM in 2015 from July 15 to 31, 2015, after existing questionnaire items were modified. The collected data were analyzed by IBM SPSS statistics 22.0, and statistical data on frequency, percentage, mean and standard deviation for each item were obtained. To figure out the characteristics of the subjects and the relationship between their occupational characteristics and the usage of CAD/CAM, crosstabs, independent-samples t-test and one-way ANOVA were utilized. As for the usage of CAD/CAM in 2011, the results of Lee Jong-do, Park Kwang-Sig(2011)'s study were selected, and then a comparative analysis was made. The level of significance was all set at .05. Total 250 questionnaires were distributed to them, and 190(76.0%) were returned. After excluding 23 whose answers were uncertain or seemed to lack reliability, total 167(66.8%) were used in final analysis. Results: As a result of analyzing the usage of CAD/CAM that was one of dental technologist duties, there was a great increase in the ownership of CAD/CAM in their workplaces from 2.4 percent in 2011 to 71.7 percent in 2015, and there was an improvement in awareness about it and the necessity of its usage as well. In 2011, the Internet and mass media were the most common route that they got to know about it. They had a strong tendency to acquire related knowledge through education in 2015, and there were some changes in the products that they used or preferred. In both years, the great merit of CAD/CAM was the simplified manufacturing process of restoration, and it had another great advantages in 2015 such as the improved quality of restoration or improved environments for dental technology. Concerning disadvantages, high price was a big problem in 2011. In 2015, not only price but the burden of material costs, frequent breakdown, poor demand among dental clinics and a lack of CAD/CAM professionals were pointed out a lot. In the future, this researcher intends to make research to seek ways of improving CAD/CAM professionals. Conclusion: There was more awareness of CAD/CAM in 2015 than in 2011 when the changes in awareness of it were analyzed, and the finding suggest the necessity of sustained education and concern.

• 대한치과보철학회지
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• 제58권1호
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• pp.42-49
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• 2020

무치악 환자에게서 의치의 제작은 통상적이고 전통적인 방법을 따를 경우 최종 의치 장착까지 여러 단계를 거쳐야 하며 이로 인한 환자의 잦은 내원이 불가피하다. 또한 기공 과정 상에서 나타나는 중합수축에 의한 오차나, 의치의 파절이나 분실 시 빠른 재제작의 어려움 등의 단점이 존재하였다. 하지만 최근 치과 분야에서 computer-aided design and computer-aided manufacturing (CAD/CAM) System이 사용되기 시작하였고, 의치 제작에까지 그 영역을 넓히기 시작하였다. CAD/CAM System을 이용하여 의치를 제작하면 첫 번째 내원 시에 인상채득과 악간관계의 기록, 인공치의 선택 등이 동시에 이루어지고 두 번째 내원 시 의치의 장착이 가능하기 때문에 환자의 내원 횟수와 진료시간을 감소시킬 수 있다. 또한 3D-Printing 기술을 이용하기 때문에 중합수축에 의한 기공 오차를 감소시킬 수 있다. 현재 상용화 되어 있는 CAD/CAM System을 사용한 의치로는 DENTCA CAD/CAM denture (DENTCA Inc., Los Angeles, CA, USA)가 있다. 본 증례에서는 상, 하악 완전 무치악 환자에게서 conventional 한 방법과 DENTCA CAD/CAM Denture System을 사용하는 방법을 동시에 사용하여 두 쌍의 총의치로 수복함으로써 발음, 저작, 연하 등의 기능적인 측면뿐만 아니라 심미적인 측면에서도 양호한 결과를 얻었기에 이를 보고하고자 한다.