• Journal of Welding and Joining
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• v.9 no.2
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• pp.11-19
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• 1991

1. 16bit 개인용 컴퓨터인 IBM-PC/AT수준에서 레이저 가공을 위한 임의의 도형을 입력하여 DXF File로 출력하고, External명령인 AutoCAM을 추가하여 AutoCAM의 실행이 가능하였으며 AutoCAM의 종료후에는 다시 AutoCAD로 작업이 가능하다. 2. 개발한 AutoCAM은 AutoCAD Ver 2.6i로부터 Release 10까지의 DXF File을 읽어 Graphic 출력이 가능하다. 3. 가공 경로를 NC프로그램이 임의로 선정가능하면서, 가장 능률적인 가공작업이 수행될 수 있 도록 연속 또는 최인접 도형요소를 자동 선정하고 이의 조건에 따른 Auto Mode의 NC프로그램 생성이 가능하다. 4. 생성된 NC프로그램을 레이저 가공기에 전송하여 가공실험을 실시한 결과, 생성된 NC 프로 그램은 거의 수정하지 않아도 작동이 가능한 정도의 만족할 만한 결과를 얻었으므로 실용화에 큰 문제가 없는 것으로 사료된다. 이상과 같이 레이저 가공을 위한 CAD/CAM시스템은 초심자등의 이용상의 편리를 위하여 대화식으로 하였으며 사용된 언어도 Quick BASIC으로 자체 개발하 였으므로 앞으로 이 분야의 연구 및 실용화를 위한 기초자료로 활용될 수 있을 것으로 사료된다.

• Advances in Computational Design
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• v.5 no.1
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• pp.13-34
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• 2020

As small size and complex metal machining components demand increases, cutting processes in microscale become necessary. Ball-end milling is a commonly used finishing process, which nowadays can be applied in the microscale size. Surface quality and dimensional accuracy are two basic parameters that affect small size components in their assembly and functionality. Thus, good quality can be achieved by optimizing the cutting conditions of the procedure. This study presents a 3D simulation model of ball-end milling in microscale developed in a commercial CAD software and its optical and computing results. These carried out results are resumed to surface topomorphy, surface roughness, chip geometry and cutting forces calculations that arising during the cutting process. A great number of simulations were performed in a milling machine centre, applying the discretized kinematics of the procedure and the final results were compared with measurements of Al7075-T651 experiments.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.6
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• pp.1204-1208
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• 2012

According to the rapid development of cell phone and camera industry, all of electronic products obtain small-size, high-performance and variety. Therefore, PCB also obtains high-integration, multi-layers and high-specification rapidly. Among the digital cameras which are continuously evolved and developed, the market of mirror-less camera and hybrid digital camera is continuously increased because of the customer's request for small-size and weight lightening, except for DSLR camera. Therefore, the difficulty of PCB design is gradually increased and design L/T is longer according to the high-specifications, low-current and high-performance components. This thesis suggests the method to reduce L/T for PCB design applied to the reduction of digital camera's developing period and manufacturing period.

• Progress in Superconductivity
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• v.8 no.1
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• pp.46-53
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• 2006

Magnetocardiography(MCG) has been proposed as a novel and non-invasive diagnostic tool for the detection of cardiac electrical abnormality associated with myocardial ischemia. In our previous study, we have proposed a new classification method of MCG parameters, based on the different populations of the parameters between coronary artery disease(CAD) patients, symptomatic patients and healthy volunteers. We used four parameters, representing the directional changes of the electrical activity in the period of an R-ST-T interval. In patients with chest pain and without ST-segment elevation, who were selected consecutively from all patients admitted to the hospital in 2004, the patients with CAD could be classified with a higher sensitivity than conventional methods, showing that the proposed method can be useful for the diagnosis of CAD with MCG. In this study, we examined the validity of the algorithm with the prior probability distribution in diagnosis of new patients admitted to the hospital in 2005. In the results, presence of CAD could be found with sensitivity and specificity of 81.3% and 71.4%, respectively, in patients with chest pain and non-diagnostic ECG findings.

• Korean Journal of Adult Nursing
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• v.29 no.1
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• pp.32-40
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• 2017

Purpose: The purpose of this secondary data analysis was to identify factors influencing a relapse among patients with coronary artery disease (CAD). Methods: Of 250 participants enrolled in the original study 75 were selected as there was no relapse for more than one year following the initial treatment and 54 were selected because there was a relapse. Data were analyzed using ${\chi}^2$ test, t-test or F test to determine if there were any significant differences in the study variables relative to the status of relapse. Predictors were calculated by logistic regression. Results: Autonomy supported by healthcare providers was the significant predictor for relapse in patients with CAD. Patients with low autonomy supported by healthcare providers was 3.91 times more likely to relapse than patients with high autonomy supported. Patients with diabetes were at greater risk of recurrence. Conclusion: Secondary prevention of CAD is a major task for patients with CAD. Behavioral strategies for cardiovascular risk reduction are essential and autonomy supported by healthcare providers should be included in their strategies.

• Korean Journal of Adult Nursing
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• v.21 no.1
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• pp.1-12
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• 2009

Purpose: This study was to examine the food intake and family support of patients with Coronary Artery Disease(CAD). Methods: 90 hospitalized patients who received CAD medical treatment were randomly selected. The food intake frequency and family support instrument were utilized. Collected data was analyzed by SPSS/WIN 14.0: t-test, $x^2$-test and Pearson's correlation coefficient. Results: The mean score of food intake frequency was 5.65(total mean score 97.50) which was relatively healthy food intake based on the CAD treatment guidelines. Undesirable food intake items were fruit, fish, milk etc. The mean score of family support was 2.44(range: 1 - 4). Food intake showed a significant(p < .001) positive correlation with family support. There was significant difference(p < .05) on family support according to exercise. There was significant difference(p < .05) on LDL level, one of the CAD risk factors, between first admission patients and readmission patients. Conclusion: These findings suggest that nursing intervention education programs should be developed to appropriately care for CHD patients for needed changes.

• Special Issue of the Society of Naval Architects of Korea
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• 2011.09a
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• pp.101-105
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• 2011

In most shipbuilding company, cutting procedure is proceed by cutting machine which run by CNC(Computer Numerical Code) data. In our cutting process, all CNC data is created by our nesting post processor system automatically. Among them, in case that cutting piece in the remnant plate, our system creates only one piece CNC data. Because remnant plate is not typical shape, and ship designers don't know remnant plate shape and quantity. In can happen some merit and good point if we modify 1:1 piece NC data by shorten cutting path, reducing cutting time or re-arrangement piece. For modifying cutting data, outside workers have to call to ship designer or have to go to NC control room where control the CNC system and cutting machine. It makes stop work process, and it waste time. In this paper, we introduce a program that can modify and replace 1:1 NC data with continuous or common NC data automatically.

• Journal of Technologic Dentistry
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• v.42 no.3
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• pp.228-233
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• 2020

Purpose: This study aimed to assess and compare the marginal fit of ceramic-based hybrid resin restoration (HYB) and zirconia restoration (ZIR) for dental computer-aided design/computer-aided manufacturing systems. Methods: A stainless steel master model was produced. The impression was first made with silicone, and then stone working models were produced. A total of twenty restorations were fabricated with two different materials: ZIR and HYB. The silicone film thickness of the marginal gap was measured using a digital microscope; digital photos were taken at a magnification of ×160, and then analyzed using a measurement software. The values of the result were evaluated with the independent-sample t-test (α=0.05). All statistical analyses were performed with a statistical software. Results: The mean values for the marginal gap was 37.14±2.96 ㎛ for HYB, compared with 40.37±5.26 ㎛ for ZIR. No significant difference was found between ZIR and HYB (p=0.107). Conclusion: As a result, the marginal fit of the restoration fabricated using the hybrid resin was better than that of the restoration fabricated using zirconia. Also, the marginal fit of all groups was below the clinical acceptable range of 120 ㎛. Thus, HYB for dental CAD/CAM system in this study is expected to be suitable for clinical use in dentistry.

• Korean Journal of Human Ecology
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• v.8 no.1
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• pp.165-178
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• 1999

Knitwears it was only for the innerwear, but which has become more available for sportswear and highly valuable formal-dresses for women's apparel and is set a trend toward high value-added products worldwide. Also the industry connected knitwears is more widely applicative than woven industry and is running on the well founded basement for the small enterprises. This study notes that what problems are caused and which utilities can be expected when we design knitwears by Primavision and Texpia CAD system considered the programs for development of domestic knitwears industry. There are much various benefits for designing knitwears from CAD system as shortening working hours, convenience, accuracy, quality control and productivity. It doesn't depend on designer's technique, sense and experiences, but provides, through building the design accuracy, chance to have a precise communication with buyers to be satisfied with the multiplicity, uniqueness and high-quality resulting from reducing the mistake on the operation. But there are some problems for using CAD design system those are no selections for the form, type and thickness of the yarn. Even though it is knitted by the same gauge, the texture conditions show complete difference if the form and thickness is different with. The gauge control without regarding those ought to be improved and the yarn designing function should be appended like in a tektite design. And the CAD design system can not reflect the variables of operating knitting machine and needle. The CAD design system provides the manufacturers with merits those they can change the colors easily to select which one appeals to the customer and check the effects of producing and modeling on monitor. But, in the each producing progress, there are still problems to reduce the practical steps, so intensive care is required of each part.

• The Journal of Advanced Prosthodontics
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• v.7 no.3
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• pp.233-239
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• 2015

PURPOSE. This study aimed to evaluate the fit of zirconia ceramics before and after veneering, using 3 different veneering processes (layering, press-over, and CAD-on techniques). MATERIALS AND METHODS. Thirty standardized zirconia CAD/CAM frameworks were constructed and divided into three groups of 10 each. The first group was veneered using the traditional layering technique. Press-over and CAD-on techniques were used to veneer second and third groups. The marginal gap of specimens was measured before and after veneering process at 18 sites on the master die using a digital microscope. Paired t-test was used to evaluate mean marginal gap changes. One-way ANOVA and post hoc tests were also employed for comparison among 3 groups (${\alpha}$=.05). RESULTS. Marginal gap of 3 groups was increased after porcelain veneering. The mean marginal gap values after veneering in the layering group ($63.06{\mu}m$) was higher than press-over ($50.64{\mu}m$) and CAD-on ($51.50{\mu}m$) veneered groups (P<.001). CONCLUSION. Three veneering methods altered the marginal fit of zirconia copings. Conventional layering technique increased the marginal gap of zirconia framework more than pressing and CADon techniques. All ceramic crowns made through three different veneering methods revealed clinically acceptable marginal fit.