• Journal of the Korean Vacuum Society
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• v.19 no.2
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• pp.96-104
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• 2010

We suggest here a cost-effective replica fabrication method for transparent and hard molds for imprinting lithography such as NIL and S-FIL. The process starts with the use of a replica hard mold from a master, using a polymer copy as a carrier. The polymer copy as a carrier was treated by soluble process for forming anti-adhesion layer. Duplicated hard molds can eliminate direct contact between a hard master and a patterned polymer on a substrate and the generated contamination of a master during the imprinting process. The replica hard mold exhibits the glass-like properties introduced here, such as transparency and hardness, make it appropriate for nanoimprint lithography and step-and-flash imprint lithography.

• IE interfaces
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• v.12 no.1
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• pp.68-78
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• 1999

A noncircular cutting such as a piston cutting has depended on the copy-machining because of its complex shape. But the copy-machining needs a master model and brings about a low quality of the piston caused by being worn out of the master model. And the lower cutting speed reduces the productivity. In this paper, for solving these problems, a specialized software system and its subsequent procedure are presented. The shape of a piston consists of an oval, an offset, recesses, and eccentricities. The paper describes these shapes as a consistent equation that is a function of the rotational angle and the position of longitudinal direction(Z-axis). It is simple to define the characteristic geometry of a piston and to generate a tool path for CNC machining. This paper proposes the a proper structure of a 4-axes CNC(Computerized Numerical Control) lathe for machining the piston. As well as X-axis and Z-axis, are attached to the machine a C-axis for rotation and a Y-axis for higher speedy prismatic motion parallel to X-axis.

• Structural Engineering and Mechanics
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• v.4 no.1
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• pp.73-89
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• 1996

In Lagrangian mechanics, attention is directed at the body as it moves through space. The region occupied by the body is called a configuration. All body points are labelled by the position they would have if the body were to occupy a chosen reference configuration. The reference configuration can be regarded as an extra fictional copy where notes are kept. As the body moves and deforms, it is important to correctly observe the use of each configuration for computational purposes. The description of strain is particularly important. The present work establishes clearly the role of each configuration in total and in incremental forms. This work also details the differences between gradient and configurational calculus.

• Journal of the Korea Safety Management & Science
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• v.6 no.3
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• pp.327-337
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• 2004

The soaring increase in the number of Internet users combined with the constant computerization of business process has created new opportunities for computer criminals and terrorist. Fortunately, the computer security field is also progressing at a brisk rate. In particular, the field of computer forensics brings new ways of preserving and analyzing evidence related to computer crime. Computer forensics is a new emerging professions of the 21st century. It is the collection, preservation, analysis, and presentation of computer related evidence. For this reason, the various technology of computer forensics is regarded as a powerful tool for suppressing computer crime. Our aims is to introduce the overview of computer forensics technology. We also present the survey results of the state of the art of computer forensics in the domestics and of foreign country.

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.3
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• pp.243-249
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• 2001

Statement of the problem. The interest in all-ceramic restorations has increased as more techniques have become available. With the introduction of machinable dental ceramics and CAD/CAM systems or Copy-milling systems there is a need for evaluating the quality levels of these new fabrication techniques. Purpose. This study was to evaluate the fitting accuracy of machined all-ceramic crowns made out of an industrially prefabricated feldspathic porcelain. Material and Methods. Three master models with different cutting depth (0.8mm/1.0mm/1.2mm)were produced using a palladium-silver alloy. A total of 36 working dies, 12 of each form, was used for the modellation of prototype resin copings and 36 additional crowns, 12 of each cutting depth, were produced by using the $CEREC^{(R)}2$ system for all crowns. The maginal fit of all 72 crowns was then evaluated on their respective master die at 54 circularly staggered points of measurement per crown under a fixation pressure of 30 N by using a computerized video image system. Results. The medians of the copy-milled $CELAY^{(R)}$ crowns ranged from 29 to $36{\mu}m$. The highest value for the marginal gap was found in group B (cutting depth 1.0mm) at $107{\mu}m$. The median for the $CEREC^{(R)}2$ crowns was found between 43.5 and $70{\mu}m$. The maximum values for all three groups ranged from $181{\mu}m$ to $286{\mu}m$. With $286{\mu}m$ the highest value for marginal gap was found in group C. the Kruskal-Wallis test and multiple comparisons analysis procedure revealed a significant influence of the production technique on the marginal fit in all three groups (p<0,02). Conclusion. 1. The $CELAY^{(R)}$ system is capable to produce all-ceramic crowns with a significantly better marginal fit than the $CEREC^{(R)}2$ system. 2. As far as premolar crowns produced with the $CEREC^{(R)}2$ system are concerned, the cutting depth has a significant influence on fitting accuracy. 3. The production of crowns with an acceptable marginal fit is possible with both systems. However, adhesive luting is recommended for milled feldspathic porcelain crowns.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.2
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• pp.417-430
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• 1997

The purpose of this study was to compare the fracture resistance of copy-milled and conventional In-Ceram crown. Four groups of ten uniform sized all-ceramic crowns were fabricated. In-Ceram Spinell and In-Ceram Alumina crowns were fabricated as control group, Celay In-Ceram Spinell and Celay In-Ceram Alumina crowns were fabricated as test group. All specimen were cemented on stainless steel master die with resin cement, and stored in $37^{\circ}C$ water for 1 day prior to loading in Instron testing machine. Using a steel ball at a crosshead surfed of 0.5mm/min, the crowns were loaded at $30^{\circ}C$ angle until catastrophic failure occurred. The results obtained were as follows : 1. With the value of $984.8N{\pm}103.67N$, the strength of Celay In-Ceram Alumina crowns had a significantly higher fracture strength than conventional In-Ceram Alumina crowns ($876.2N{\pm}92.20N$) (P<0.05) 2. The fracture strength of Celay In-Ceram Spinell crowns($706.3{\pm}70.59N$) was greater than that of conventional In-Ceram Spinell crowns($687.4{\pm}90.26N$), but there was no significant difference(P>0.05). 3. The In-Ceram Alumina crowns had a significantly higher fracture strength than In-Ceram Spinell crowns in both methods(P<0.05). 4. Ther order of fracture strength was as followed : Celay In-Ceram Alumina, In-Ceram Alumina, Celay In-Ceram Spinell and In-Ceram Spinell crowns

• Journal of the Korean Society for Library and Information Science
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• v.25
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• pp.415-444
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• 1993

Chiyou Park(박치유) published Bang-kak-bon(방각본) at Taein(태인) between 1799-1806 with Ichae Jun( 전이채). They published Sa-yo-chwi-sun(사요취선) and Sa-moon-you-chwi-cho(사문류취초) in 1799. Between 1800-1806 they published Taemyongyoolsi(대명율시). Kongjatongki(공자통기). Hyokyongtaei(효경대의), Tongjaseup(동자습), Komoonchunchip(고문전집), Kongjakao(공자가어), Nongkachipsung(농가집성), and Koohwangcharlyo(구황촬요) until they departed each other in publication of Bang-kak-bon(방각본), In 1823 Chiyou Park(박치유) published again Sayochwisun(사요취선) at Kookockchae (구곡제). He published Taeseungkisinronsopilsacki(대승기신논소필삭기) and Chackpupkwikam(작법구감) between 1815-1827 with Backpataesa(백파대사) who was a Buddhism Monk of Woonmoon-am(운문암) in Backyang Mountain(백양산), Backpataesa(백파대사) was born in 1767, became a monk in 1784 and died in 1851. Backpa(백파) was a famous Budhism scholar who disputed the truth of Zen (선) with Choosa, Chunghee Kim We (추사김정희). He rewrote Taeseungk.isinronso-pilsacki(대승기신논소필삭기), Chackpupkwikam (작법구감), and Zenmoonsookyong (신문수경). Chasun (자선) of Songdynasty (송조) rewrote Pilsakcki(필삭기) before Backpa(백파), which was published at Myouduck-am(묘덕암) of Myongdynasty(명조). It was republshed in Korea several times which are called Sankyesa Copy(쌍계사본) of Back-am(백암), Suckwangsa Copy(석왕사본) of Hamwol(함월), Bongchungsa Copy(봉정사본) of Hoeun(호은), Woonmoon-am Copy(운문암본) of Backpa(백파). Chackpupkwikam(작법구감) is a book of Buddism worsip form which was made of Chaepanmoon (제반문), Paneumchip(범음집), Chineunchip진음집). As a Bangkakbon(방각본) publisher, Chiyou Park believed in Buddhism so heartily that be published Bangkakbon(방각본) and Amkakbon(암각본) which are saved until today.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.12 s.177
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• pp.16-21
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• 2005

Photonic crystals, periodic structure with a high refractive index contrast modulation, have recently become very interesting platform for the manipulation of light. The existence of a photonic bandgap, a frequency range in which the propagation of light is prevented in all directions, makes photonic crystal very useful in application where the spatial localization of light is required, for example waveguide, beam splitter, and cavity. However, the fabrication of 3 dimensional photonic crystals is still difficult process. A concept that has recently attracted a lot of attention is a planar photonic crystal based on a dielectric membrane, suspended in the air and perforated with two dimensional lattice of hole. The fabrication of Si master with pillar structure using hot embossing process is investigated for two dimensional, low-index-contrast photonic crystal waveguide. From our research we show that the multiple stamp copy process proved to be feasible and useful.

• (The)Study of the Eastern Classic
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• no.41
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• pp.211-247
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• 2010

The purpose of this article is to consider the status and the value of a different book of Chunghyangjeon that Professor Park Sunho possesses. Chunghyangjeon that Professor Park Sunho possesses has the text in Chinese and in Korean. Compared with Chullidaebon, Chunghyangjeon that Professor Park Sunho possesses includes deletion, contraction and addition. Chullidaebon has many mistakes while Parkbon in Chinese shows that the mistakes were corrected. According to the standard, Parkbon in Chinese is similar to Mansongbon and Donambon rather than Chullidaebon and it is more similar to Mansongbon than Donambon. In Parkbon in Chinese, hypocrisy of Yangnyeongdaegun is weakened while his negative personality is magnified. And psychological description of Yangyeongdaegun is weakened and Chunghyang's beauty is magnified. Parkbon in Korean shows deletion, contraction, addition, and change. It doesn't show consciousness of lineage and deletes hypocrisy and negative personality of Yangnyeongdaegun. Also, the phrases are being deleted and contracted, which are difficult for those who do not master Chinese literature or Chinese poems. The professor Park Sunho's copy is more significant than other novels circulated at that times, for it is bound along with a copy in Korean. Compared with other editions of Chunghyangjeon and other classical novels circulated, that kind of edition, which included Korean copy, is very peculiar. The Korean-including edition shows that the Chinese literate tried to share the novel with persons who are Korean literate but cannot read Chinese characters.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.3B
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• pp.375-390
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• 2004

Domain Name System(DNS), one of the most important Internet services, handles mapping from host names to Internet addresses and vice versa, and precedes many Internet applications such as Web, e-mail, file transfer, etc. In this paper, we propose a structural design of a generic name server system providing name services for a huge domain for the purpose of improving the performance as well as the reliability of the system. We demonstrate the validity of the design by implementing and running a testbed system. Our testbed employs a couple of master name sowers for distributing the service overhead over two, rather than one, servers and for achieving high availability of the system as a whole. We suggest the use of dynamic update to add and delete records from a zone for which the name server has authority. The slave name servers located remotely then get a new, updated copy of the zone via incremental zone transfers(IXFRs). The experiments with the implemented testbed show that the proposed structure would easily manage increasing demands on the server power, and be highly available in the face of transient faults of a module in the system.