• 한국정밀공학회지
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• 제25권12호
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• pp.132-138
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• 2008

Recently, mastering processes for high density optical disc such as Blu-ray disc rely on electron beams, which are operable in only vacuum. In the mastering process, one of the most important tasks is to design precision stages for providing precise positioning of the works with respect to the source in a high vacuum environment. In this paper, we have developed a precision rotation table usable in the electron beam mastering. The rotation table adopted air bearings for a high positioning repeatability and velocity stability. The air leakage from the air bearings has been minimized by employing the differential exhaust scheme using three steps of air drain. The design parameters such as diameters of exhaust lines, seal lengths, and pumping speeds were decided according to the optimization method using genetic algorithm. The performance on the vacuum level of the rotation table was evaluated experimentally and theoretically. The results indicate that a vacuum level of $10^{-4}$ Pa is achieved with operation of air bearings in a vacuum chamber, which is sufficient for the electron beam mastering.

• 한국수학사학회지
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• 제27권1호
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• pp.31-45
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• 2014

The book Su Hak Ip Mun(數學入門, Introduction to Mathematics) is one part of 5 sections of the book Seung Aeh Ill Chan(升厓日簒), which is a hand written manuscript in Chinese characters and the author and the date of writing is unknown. The book Seung Aeh Ill Chan begins with the song of division table so called Guguiga(九歸歌). We first investigate and compare the writing pattern of this with other old Korean mathematical books. Next, we investigate typical expression and calculation methods of mathematical contents and terminologies used in Su Hak Ip Mun and also figure out oddities of writing pattern of mathematical expression and cultural circumference of several problems dealt in the book. From these analysis and investigation, we estimate the writing date of Su Hak Ip Mun later than the year 1723 on which Su Ri Jeong On(數理精蘊) was first published. And we presumably guess that Guguiga and Su Hak Ip Mun are made not for practical use or theoretical purpose but for text to teach students.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.959-962
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• 2002

This paper presents a method of constructing the universal multiple processing element unit(UMPEU) based on De Bruijn Graph. The proposed method is as following. Firstly we propose transformation operators in order to construct the De Bruijn graph using properties of graph. Secondly we construct the transformation table of De Bruijn graph using above transformation operators. Finally we construct the De Bruijn graph using transformation table. The proposed UMPEU is capable of constructing the De Bruijn geraph for any prime number and integer value of finite fields. Also the UMPEU is applied to fault-tolerant computing system, pipeline class, parallel processing network, switching function and its circuits.

• 공학논문집
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• 제4권1호
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• pp.35-45
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• 2002

This paper deals with the scheduling problems which are the most important subtask in High-Level Synthesis. Especially, we have concentrated our attentions on the data-path scheduling which can get the structural informations from the behavioral algorithm as a first step in synthesis procedure. Suggest Forward scheduling methode is executed the ASAP and ALAP scheduling to use the fifth – order elliptic wave filter of a standard benchmark model, and then it is drawing up T.N matrix table by the number of resource and control-step, using the table extract of the simple than down-limit value of the control-step for the number of given resource to use this table. All of existing list scheduling techniques determine the priority functions first, and then do the operation scheduling, But, the suggested forward scheduling technique does the schedule first, and determines the priority functions if needed in scheduling process.

• 대한한의학원전학회지
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• 제25권4호
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• pp.105-113
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• 2012

Objectives : Acquiring information from symptoms is one of the important method to gain clinically available information in korean medicine. Therefore, up to now, study of symptom terms was frequently implemented in promotion of various information project. In data extraction methods using symptom information from DB, information search using synonym and method using ontology is studied and utilized. However, considering concept of symptom has essential information of appeared body area and phenomenon we think that extending synonym and ontology relationship in symptom terms can be useful for search and set to this study. Methods : We collect terms relevant to human body area and structure described in Donguibogam. Synonymous relationship between collected terms is organized. Relationship between collected terms is build to human-body-knowledge table which has form of Concept+Relation+Concept. Type of relationship is limited on a range of expressing content about parts of human body. Result & Conclusion : Search condition is generated automatically using relationship of the upper area in knowledge table contents. Information of next and previous acupuncture point, upper and lower acupuncture point, left and right acupuncture point can be searched using information of acupuncture point location, order, relative position in area, direction in knowledge table contents.

• 한국인쇄학회지
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• 제25권1호
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• pp.121-133
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• 2007

The CMS(color management system) software was to enable consistent color reproduction from original to reproduction. The CMS was to create RGB monitor and printer characterization profiles and then use the profiles for device independent color transformation. The implemented CMM(color management module) used the CIELAB color space for the profile connection. Various monitor characterization model was evaluated for proper color transformation. To construct output device profile, SLI(sequential linear interpolation) method was used for the color conversion from CMYK device color to device independent CIELAB color space and tetrahedral interpolation method was used for backward transformation. UCR(under color removal) based black generation algorithm was used to construct CIELAB to CMYK LUT(lookup table). When transforming the CIE Lab colour space to CMYK, it was possible to involve the gray revision method regularized in the brightness into colour transformation process and optimize the colour transformation by black generation method based on UCR technique. For soft copy colour proofing, evaluating several monitor specialism methods showed that LUT algorithm was useful. And it was possible to simplify colour gamut mapping by constructing both the look-up table and the colour gamut mapping algorithm to a reference table.

• 한국생산제조학회지
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• 제22권4호
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• pp.761-766
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• 2013

A precision linear motion table plays a crucial role in manufacturing systems used in various industries such as machine tools, semiconductors, and nanofabrication. In particular, one of the most typical mechanisms for a linear motion table is to use a ballscrew and LM guides. However, this mechanism is inevitably influenced by friction because of the relative motion in its joint regions. One of the most complex phenomena in friction is the hysteresis behavior of dynamic friction, which was compared with the steady dynamic friction that was presented using a Stribeck curve in this study. Therefore, we investigated the dynamic friction and its hysteresis behavior using a miniaturized linear table equipped with a ballscrew and LM guides that were lubricated with grease. Subsequently, it could be seen that hysteresis could be considered a time delay after zero-velocity crossing and that it was influenced by acceleration.

• 농업과학연구
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• 제31권1호
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• pp.1-8
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• 2004

식물생장조절제인 Seaweed extracts(GA14) 처리에 대한 수도 품종간 묘소질 및 본답에서의 생육, 수량 및 식미관련형질을 조사한 결과는 다음과 같다. 1. 생육초기의 묘소질은 최아 처리보다 최아시와 본엽 2-3엽기에 2회 처리한 것이 간장, 엽장, 엽폭, 분얼수, 근장에서 두 품종 모두 높았고, 출수기 역시 빨랐다. 2. 본답에서의 등숙율은 무처리구보다 처리구에서 주남벼가 0.3%의 증가를 보인 반면에 동안벼는 무처리구보다 처리구가 0.5%의 감소를 보여, 개화기의 일조 및 기상과 밀접한 것으로 나타났다. 3. 1,000립중은 처리구가 무처리구에 비해 주남벼가 4.0g, 동안벼가 2.0g의 증가를 보였다. 4. 10a당 정조수량은 처리구가 무처리구에 비해 주남벼와 동안벼가 각각 3%와 4%의 증수효과를 보였다. 5. 외관특성은 정상립이 처리구에서 두 품종 모두 4% 정도 높았고 피해립, 분상질립, 동할립은 감소 경향이었으나 쇄립은 증가하는 경향을 보였다. 6. 식미관련형질은 주남벼의 경우 단백질, 수분, 아밀로스 함량이 비슷하였으나 식미값은 처리구가 높았고, 동안벼의 경우 단백질, 수분, 아밀로스 함량은 비슷하였으나 식미값은 무처리구가 약간 높게 나타났다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.77-78
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• 2006

This paper presents a signal quality estimation technique for QAM modulation systems. By making a LUT(Look-up table) putting the number of N enough, we can derive estimated SNR from LUT even though N is small. That is so called MOTM algorithm. In 16-QAM, the distance $d_a$, between adjacent symbols is always invariable, so absolute value of R(the amplitude of signal) minus $d_a$ has a always same signal distribution value. This value does not form a Gaussian shape but, by making a little bit correction, we can make this symmetrical. So, from the received symbol value, by using LUT we can easily derive the estimated SNR. By considering this, we introduce a signal quality estimation technique for QAM schemes. This proposed method can be applicable to high order modulation schemes and wide range of signal to noise ratio.

• 한국정밀공학회지
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• 제30권12호
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• pp.1303-1312
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• 2013

We report an ultra-precision lathe designed to machine micron-scale features on a large-area roll mold. The lathe can machine rolls up to 600 mm in diameter and 2,500 mm in length. All axes use hydrostatic oil bearings to exploit the high-precision, stiffness, and damping characteristics. The headstock spindle and rotary tooling table are driven by frameless direct drive motors, while coreless linear motors are used for the two linear axes. Finite element method modeling reveals that the effects of structural deformation on the machining accuracy are less than $1{\mu}m$. The results of thermal testing show that the maximum temperature rise at the spindle outer surface is approximately $0.5^{\circ}C$. Finally, performance evaluations of the error motion, micro-positioning capability, and fine-pitch machining demonstrate that the lathe is capable of producing optical-quality surfaces with micron-scale patterns with feature sizes as small as $20{\mu}m$ on a large-area roll mold.