• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.7-10
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• 2001

We have developed a prototype dedicated CAM system for machining a human bust that is not a relief. The input is STL file format, and the output is NC-codes for machining on a 3-axis general purpose CNC milling machine with an index table attached. Main modules are STL import, STL transformation, modeling jig/fixture, master model generation, and calculation of machining area. System architecture is proposed and main modules are briefly described. We adopted the angle between tool-axis and the surface normal vector to calculate machining area, and tested at several degrees.

• The Journal of the Korean dental association
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• v.12 no.9
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• pp.691-694
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• 1974

The trends of restoration on abrased teethis mostly based on gnathology or on practical experience. This study was performed on plaster models from 60 young men whose teeth and occlusion are clinically normal. A pair, upper and lower models, were mounted on HANAU articulator. Iron ball bearing 0.2mm 0.5mm 0.7mm and 1.0mm in diameter was attached on mesiobuccal cusp of upper first molar. [table I] Long ribbon shape of cold cure resin was inserted and jaw was closed gently so as not to move disturb original position of iron ball. The resin bite registration was measured minimun thickness from each lingual cusps of upper jaw and buccal cusps of lower jaw by means of Bowley gauge. The results were as follows (graph). 1) The distance from upper lingual cusps and lower buccal cusps: backward cusps showed smaller than standard cusp (upper mesio-buccal cusp) and forward cusps showed longer than standard. 2) The measurements from upper lingual cusps are not coincide with lower buccal cusps.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.8 s.197
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• pp.89-96
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• 2007

In this paper, a new air bearing stage with magnetic preload and a linear motor has been developed for the small precision machine systems. The new air bearing stage is unique in the sense that permanent magnets attached bottom of the iron core of table are used not only for preloading air bearings in vertical direction but also for generating thrust force by current of the coil at base. The characteristics of air bearings using porous pads were analyzed with numerical method, and the magnetic circuit model was derived for linear motor for calculating required preload force and thrust force. A prototype of single axis miniature stage with size of $120(W){\times}120(L){\times}50(H)\;mm^3$ was designed and fabricated and examined its performances, vertical stiffness, load capacity, thrust force and positioning resolution.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.592-598
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• 1992

For a high bandwidth, accurate end of arm motion control with good disturbance rejection, the, Momentum Management Approach to Motion control (MMAM) is proposed. The MMAM is a kind of position control technique that uses inertial forces, applied at or near the end of arm to achieve, high bandwidth and accuracy in movement and in the face of force disturbances. To prove the concept of MMAM, the, end point, control of a flexible manipulator is considered. For this purpose, a flexible beam is mounted on the x-y table, and the MMAM actuator is attached on the top of the flexible beam. A mathematical model is developed for the flexible, beam being controlled by the, MMAM actuator and slide base DC motor. A system identification method is applied to estimate some system parameters in the, model which can not be determined because of the complexity of the mechanism. For the end point, control of the. flexible beam, the, optimal linear output feedback control is introduced.

• ETRI Journal
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• v.32 no.3
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• pp.370-379
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• 2010

In this paper, we propose efficient masking methods for ARIA and AES. In general, a masked S-box (MS) block can be constructed in different ways depending on the implementation platform, such as hardware and software. However, the other components of ARIA and AES have less impact on the implementation cost. We first propose an efficient masking structure by minimizing the number of mask corrections under the assumption that we have an MS block. Second, to make a secure and efficient MS block for ARIA and AES, we propose novel methods to solve the table size problem for the MS block in a software implementation and to reduce the cost of a masked inversion which is the main part of the MS block in the hardware implementation.

• Magazine of the Korean Society of Agricultural Engineers
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• v.15 no.4
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• pp.3153-3159
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• 1973

Although standard method of test for liquid limit procedure is issued under the fixed designation KSF-2303 in 1968, for both of general method and on point method, the latter of which is not still favorably used among laboratory engineers with its defficiency of adquate informations. This study intended as to furnish proper information to the laboratory engineers for the use of one point liquid limit test with full advantages of time-saving and labor-saving. further more, the following conversion formula to the one point method VS. general method is presented by the results of analytical study on 1017 Soil sampls existing liquid limit test data The formula is; $$W_L = W(\frac{N}{25})^{0.118}$$ The conversion factor (table-4) is also attached for the convenience of the users.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.11a
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• pp.1108-1110
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• 2012

파일 시스템은 컴퓨터에서 파일이나 자료를 쉽게 발견 및 접근할 수 있도록 보관 또는 조직하는 체제를 가리키는 말이다. 기존에는 Windows에 사용되는 FAT(File Allocation Table) 파일 시스템과 NTFS(New Technology File System), Unix/Linux 등에서 주로 활용되는 ext계열 파일 시스템 등이 주된 분석 대상이었으나 스마트폰과 태블릿 PC, NAS(Network Attached Storage) 서버 등 다양한 IT기기가 보급되면서 이들 기기에서 사용되는 파일시스템을 추가적인 분석이 필요하다. 따라서 본 논문에서는 추가적으로 분석해야할 파일 시스템의 종류를 나열하고 각각의 특성을 서술하여 향후 추가 분석의 지침으로 활용하고자한다.

• Journal of the Korean Institute of Educational Facilities
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• v.21 no.3
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• pp.29-36
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• 2014

Properties of school foundation are divided into fundamental property for education and fundamental property for profit. As school sites and teachers used for educational and study activities of students, fundamental property for education includes practice sites, farms and support research attached facilities in addition to school facilities. According to the Clause 1 of Article 4 of the University Foundation and Management Regulation and the Attached Table 2 of the Same Regulation, dormitory is classified as property for education(non-profit). In other words, there is no need to create profit for dormitory management. It is supposed that there are little regional differences in construction cost of dormitory with general specifications. In this case, boarding fees of university dormitories should make no difference. This study analyzed boarding fees, depending on regional factors(Seoul, Gyeonggi-do, metropolitan cities and provinces), and depending on foundation subjects(national public university and private university), classes(four-year university and college) and principal schools-branch schools. The result of One-Way ANOVA showed that Seoul showed the highest average boarding fee and it was followed by Gyeonggi-do, metropolitan cities and provinces. Also, the average boarding fees of private universities and four-year universities were higher than national public universities and than colleges, respectively. In addition, branch school's boarding fee was higher than principal school's. Additionally, this study extracted a model using the hedonic model to see how various characteristics such as region, foundation subject and class influence the boarding fee. This study would serve as fundamental research on the boarding fee. Thus far, there have been difficulties in obtaining accurate data and analyzing boarding fees, since there is no open data about dormitories and it isn't mandatory to open it, but it is anticipated that this would be used as fundamental research for estimating and analyzing boarding fees of many universities in the future.

• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.1 s.41
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• pp.61-70
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• 2005

Shaking table tests are carried out on a single-degree-of-freedom mass that is equipped with a hybrid base isolation system. The isolator consists of a set of four specially-designed friction pendulum systems (FPS) and a magnetorheological (MR) damper. The structure and its hybrid isolation system are subjected to various intensities of near- and far-fault earthquakes on a large shake table. The proposed fuzzy controller uses feedback from displacement or acceleration transducers attached to the structure to modulate resistance of the semi-active damper to motion. Results from several types of passive and semi-active control strategies are summarized and compared. The study shows that a combination of FPS isolators and an adjustable MR damper can effectively provide robust control of vibration for a large full-scale structure undergoing a wide variety of seismic loads.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.394-397
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• 2012

Wireless sensor network is configured to be able to collect information collected from the various sensors, real-world environment wireless network. In this paper, the information collected from the wireless sensor networks in the real world using AR (Augmented Reality) data by projecting, in a variety of ways, the information collected from the wireless sensor network is utilized, which more intuitive is intended to provide to users. In this paper, stored in the DB table and the information collected from the wireless sensor network, wireless LAN (Access Point) that are placed in the sensor field and the terminal attached to the geomagnetic sensor, terminal position, after correction using acceleration sensors and augmented reality the aim is to visualize the data stored in the DB table using.