• Journal of Institute of Convergence Technology
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• v.3 no.2
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• pp.11-15
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• 2013

These days, the quality of goods is required to improve in the process of manufacturing the semiconductor through the short working hours and clean transportation. The non-contact transport device using magnetic levitation can be a solution in the manufacturing process. The non-contact transport device, using electromagnetic actuation, is the system that can actually transport them by only using attraction force from the electromagnetic source without authentic contact. Moreover, the system using electromagnetic force has a substantial number of benefits ranging from unrestricted design to unlimited expansion. Especially, the price is competitive. The non-contact transport device, using electromagnetic force, has another merits in controlling by giving the same amount of attraction force to ferromagnetic body. By controlling the currents given to coil, the operator is able to decide the direction of the transportation. In order to design the optimal system, we implemented five different things such as the presence of the links below the electromagnetic, the electromagnet changes due to coupling method, the change according to the thickness of the links below electromagnet, due to changes in between electromagnetic distance direction, and the size of the current. Through simulations and the optimum design, it seems to control easily and figure out the exact size of power. It might definitely be the non-contact transport that can sharply reduce tiny scratches and particles in the process of manufacturing the semiconductor.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.2
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• pp.21-27
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• 2023

This paper is a study on the development of an app that assists in putting alignment in golf. The proposed app measures the position and size of the hole cup on the green to provide the distance between the hole cup and the aiming point. To achieve this, artificial intelligence object recognition technology was applied in the development process. The app measures the position and size of the hole cup in real-time using object recognition technology on the camera image of the smartphone. The app then displays the distance between the aiming point and the hole cup on the camera image to assist in putting alignment. The proposed app was developed for iOS on the iPhone. Performance testing of the developed app showed that it could sufficiently recognize the hole cup in real-time and accurately display the distance to provide helpful information for putting alignment.

• Journal of the Korea Society of Computer and Information
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• v.14 no.6
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• pp.33-40
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• 2009

In this thesis, for the assessment of software development process for project complexity and project size : one of digital watermarking algorithm is selected and examined. Digital watermarking provides a solution to illegal copying of digital contents and has many other useful applications, including web broadcast monitoring, transaction tracking, authentication, copy control and device control. This thesis focused on the method for customizing software development path, considering the project environments and characteristics. The selection standard of software development path is composed of process items, based on the ISO/IEC 15721 Information Technology Guide for ISO/IEC 12207 (Software Life Cycle Process) and ISO/IEC 15504 Information technology - Process assessment. To evaluate the algorithm, a system for selecting development path, which reflected algorithm, was examined.

• Journal of the Korean Geotechnical Society
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• v.39 no.11
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• pp.23-31
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• 2023

The escalating settlements observed in concrete slab tracks pose a significant challenge in Korea, raising concerns about their adverse impact on the safe operation of high-speed railways and the substantial costs involved in restoration. A primary contributor to these settlements is identified as the utilization of rock materials sourced from tunnel construction, incorporated into the lower subgrade without the requisite soil mixing to achieve an appropriate particle size distribution. This study employs numerical analysis to evaluate the efficacy of partial reinforcement in reducing settlements in rock-filled lower subgrades. Column-shaped reinforcement areas strategically positioned at regular intervals in the lower subgrade induce soil arching in the upper subgrade, leading to a concentration of soil loads on the reinforced areas and consequent settlement reduction. The analysis employs finite element methods to investigate the influence of the size, stiffness, and spacing of the reinforced areas on settlement reduction in the lower subgrade. The numerical results guide the formulation of an optimal design approach, proposing a method to determine the minimum spacing required for reinforcements to effectively limit settlements within acceptable bounds. This research contributes valuable insights into addressing the challenges associated with settlement in concrete slab tracks, offering a basis for informed decision-making in railway infrastructure management.

• Korean Journal of Radiology
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• v.1 no.1
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• pp.38-42
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• 2000

Objective: The purpose of this study was to determine the utility of preoperative CT in predicting early recurrence of hepatocellular carcinoma after partial hepatic resection. Materials and Methods: Preoperative three-phase helical CT scans in 53 patients with hepatocellular carcinoma were retrospectively reviewed by two radiologists. In 27 patients (group I), HCC had recurred within six months, while 26 (group II) had remained disease free for at least two years. In each group, preoperative CT findings were evaluated in each group for the tumor size and number, the presence or absence of capsule, distinctness of tumor margin, perinodular extension, and the presence or absence of portal vein thrombosis. Results: In group I, a tumor capsule of tumor was seen in five of 27 patients (19%), and in group II, in 16 of 26 (62%) (p = .001). The tumor margin was distinct in eight patients (30%) in group I and in 20 (77%) in group II (p = .001). Multiple tumors, perinodular extension, and portal vein thrombosis were more frequently seen in group I but the differences were not statistically significant (p > .05). Tumor size was similar in each group (p > .05). Conclusion: Preoperative CT findings that may help predict the early recurrence of hepatocellular carcinoma after surgical resection are an absence of capsule of tumors and an indistinct margin. Reference to these findings during preoperative CT can guide clinicians in their choice of treatment.

• Journal of The Korea Institute of Healthcare Architecture
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• v.5 no.9
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• pp.107-116
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• 1999

The purpose of this study is to present reference materials for the planning and research of related environments by introducing the theoretical background and samples of the environments for older people with cognitive impairments. Major contents of the study include cognitive impairments and residential facility of older people, model environments for special care unit, therapeutic dimensions of environments, outdoor garden, activity calendar, and site-visits of the sample facilities. Some results of the study could be summarized as follows ; 1) Special care unit for the people with cognitive impairments has been required and developed. 2) Weiss Institute, Corrine Dolan Alzheimer Center, and Wood Place in Oakmont were analyzed as model environments. 3) Therapeutic dimensions such as safety & security, awareness & orientation, opportunities for socialization, regulated sensory stimulation, provisions for privacy, ties to the healthy & familiar, and autonomy & control were proposed. 4) The advantages of outdoor garden for the people with cognitive impairments were explained. 5) Activity calendar for a facility was introduced and recognized as a essential guide for environment planning. 6) Sample facilities showed small size households and various ideas of environments for the older people with cognitive impairments.

• Journal of Korean Academy of Nursing
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• v.34 no.6
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• pp.934-944
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• 2004

Purpose: This meta-analysis was conducted to evaluate the effects of a self-efficacy promoting program and analyze its components. Method: The material used for this study were 18 self-efficacy promoting program studies carried out from Jan. 1980 to Oct. 2003. The studies were analyzed in differen categories: 1) types of dependent variables 2) sample characteristics 3) types of experimental treatment conditions 4) types of self-efficacy source and 5) total amount of time Result: 1) The weighted mean of a self-efficacy promoting program ranged from 1.383 to 0.015 2) for the experimental treatment condition, exercise had a much larger effect in increasing general self-efficacy and self-care than education 3) the studies using 3 sources had a much larger effect in increasing self-care than the studies using 4 sources 4) a time period longer than 900 minutes had a much larger effect in increasing specific self-efficacy, general self-efficacy and self-care than in a time period shorter than 900 minutes. 5) effect size of specific self-efficacy was significantly higher than general self-efficacy. Conclusion: These results can be used to guide the development of a self-efficacy promoting program for nursing practice.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.271-275
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• 2001

Three dimensional flow characteristics in a liquid fuel ramjet combustor are investigated using PIV method. The combustors have two rectangular inlets that form 90 degree each other. Three guide vane is installed in each rectangular inlet to improve the flow stability. We made three cases of test combustors in which those inlet angles are 30 degree, 45 degree and 60 degree. Each combustor easily changes the size of combustor's recirculation zone with the replacement of combustors dome. The experiments are performed in the water tunnel test with the same Reynolds number in the case of Mach 0.3 at inlet. PIV software is developed to measure the flow field in the combustor and the accuracy of developed PIV program is verified with rotating disk experiment and standard data. The experimental results show that the two main streams from rectangular inlet collide near the plane of symmetry and generate two large longitudinal vortex, A large and complex three-dimensional recirculating flow is measured in the recirculation zone.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.4
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• pp.213-218
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• 2010

In this study, a star screen model was constructed to predict the dynamic characteristics of interactive waste particles and to simulate separation capability of the particle using geared type screen(star screen). In order to approach this model, it is necessary to determine the design parameters of the screen such as driving torque, percentage of open space, and capability. Thus, a dynamic star screen model was developed with a total of 32 columns of geared assembly including screen part, wastes guide, and extra joints to rotate the screen using ADAMS. Each parameter was simulated to predict the screening capability for particle size, rotating speed, and particle condition. From the results, separation ability was predicted according to the affecting variables by using the dynamic star screen model.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1997.10a
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• pp.177-182
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• 1997

The purpose of this study is to analyze how tools, guide bush type and the change of cutting speed have effects on the diameter of cutting hole, surface roughness of workpiece and roundness during the deep hole machining of SM55C with solid BTA drill by using BTA drilling system through experiment. Conclusion reached is as follows. (1) The diameter was expanded for 25${\mu}{\textrm}{m}$ at the first section and then was reduced 0${\mu}{\textrm}{m}$ and 15${\mu}{\textrm}{m}$ respectively at the 10m and 20m section comparing to the diameter of tool with respect to the variation of cutting length. (2) It was proved that roughness was below 12S for the whole section of cutting length. (3) The roundness has been below 12${\mu}{\textrm}{m}$. Regarding the polygon phenomenon, it has bee proved that not only uneven number of angle but also even number (quadrilateral, elliptical) of angle were made. (4) Variation of diameter, surface roughness of workpiece and roundness turned out to ve the best at 70m/min of cutting speed, 0.15mm/rev of feed.