• 충청수학회지
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• 제28권2호
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• pp.287-305
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• 2015

Hyperbolicity is a core of dynamics. Shadowness and expansiveness for homeomorphisms have been studied by J. Om-bach([3], [4], [5]). We study the hyperbolicity (i.e., expansivity and the shadowing property) and the Anosov relation for a closed relation.

• 폴리머
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• 제34권1호
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• pp.38-44
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• 2010

탄산칼슘/유기계 core-shell 입자를 제조하기 위해 core로는 침강성 탄산칼습을 사용하였고, shell로서는 여러 종류의 methyl methacrylate(MMA), ethyl acrylate(EA), n-butyl acrylate(BA), styrene(St), 2-ethylhexyl acylate(2-EHA)을 사용하여, 반응 온도 유화제, 개시제의 종류와 첨가량을 변화시킨 후에 유화중합을 시켜 최적의 유화중합 조건을 구하였다. 생성된 core-shell 입자의 구조는 FT-IR로, 입자크기와 형태는 입도 분석, SEM, TEM으로 각각 측정하였다. 그리고, 이 core-shell 입자에 부직포를 함침시켜 처리전후의 표면변화는 접촉각으로 확인하였다. 또한, 함침 처리 전후의 부직포/부직포 소재와 관능성 단량체 첨가한 부직포/부직포 소재의 박리 접착강도를 측정하여 상호 비교하였다. 탄산칼슘/유기 core-shell 입자 합성의 경우에는 유화제인 SDBS를 0.5 wt% 첨가한 탄산칼슘을 core로 하여 MMA와 0.1 wt% 농도의 APS를 단계적으로 주입하여 중합함으로써 탄산칼슘입자 표면에 단량체의 중합이 잘 유도될 수 있었으며 중합 도중에 새로운 중합체 입자의 생성이 적었다.

• 한국군사과학기술학회지
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• 제14권2호
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• pp.264-270
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• 2011

This paper focuses on possibility to design and fabrication new combination of bullet core to substitute current toxic material of heavy metal such as lead by environment-friendly ones. The core is designed as dual structure to manipulate the core center of gravity easily by combining materials, which of basis is tungsten of low cost and easily acquired. Those combinations are W-M series such as W-Cu, W-Sn, W-Cu-Sn, and W-Cu-Ni to target the density of lead, $11.34g/cm^3$ through powder-metallurgy. Out of four, combination of W-Cu-Ni shows the highest compression density of 96% and is confirmed as the most suitable substitution for lead due to the excellent property of matter and sintering. All combination samples is simulated on the PRODAS software for designing and structure analysis by adjusting the center of gravity of dual core samples forward and backward. The simulations confirm the similarity of current bullet core with respect to properties of mass, aero dynamics, and flying stability.

• 소성∙가공
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• 제19권7호
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• pp.411-415
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• 2010

A sandwich panel which is comprised of truss cores faced with solid face sheets is lightweight and multi-functional. So it is widely used to not only structural material but also heat transfer media in transportation field such as airplane, train and vessel. There are various core topologies such as pyramidal and tetrahedral truss, square honeycombs and kagome truss. The study focused on analytical approach to optimize compression and shear quality of the unit cell of PCM with pyramidal configuration. With various unit cell models which have the same core weight per unit area but different truss member angle, analytical solution for effective stress ($\bar{\sigma},\bar{\tau}$), peak stress ($\bar{\sigma}_{peak},\bar{\tau}_{peak}$) by yielding and buckling, relative density ($\bar{\rho}_c$) and effective stiffness ($\bar{E},\bar{G}$) have been computed and compared each other. With this approach, the most optimal core configuration was predicted. The result has become the efficient guidelines for the design of PCM core structure.

• 무역상무연구
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• 제60권
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• pp.47-77
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• 2013

The way for seller to procure the goods for selling is to produce the goods at his own factory and to buy the manufactured goods from the other company. In order to produce the goods for selling the seller have to obtain the resource from the domestic company or overseas. In the middle of producing the goods to sell, seller may breach the right of a third party based on intellectual property rights. That is to say, seller may use the machine that has not itself been patented and use a process which has been patented by a third party. Seller may manufacture the goods which themselves are subject to the third party industrial property rights. Nowadays it is stressed the importance of intellectual property rights such as a patent, brand, and design. These factors consist of the core elements of the competitiveness of the goods. Many embedded software have been used in the various sector. So the disputes regarding to the intellectual property rights is gradually increasing in number. Article 42 of CISG defines the seller's delivery obligations and liabilities in respect to third party intellectual property rights and claims. It contains a special rule for this similar kind of defective in title, which tries to provide an proper solution to the complex problems caused by such rights and claims in international transactions. When seller will apply this clause to the business fields, there are several points to which seller should give attention. First, Intellectual property is general terms in intangible property rights, encompassing both copyright and industrial property. Which matter fall within the scope of intellectual property? The scope of intellectual property can be inferred from the relevant international conventions, which are based on broad international consensus. Second, Article 42 of CISG governs the relationship between the seller and the buyer, that is to say, questions of who has to bear the risk of third party intellectual property rights. The existence of such intellectual property rights, the remedies available and the question of acquiring goods free of an encumbrances in good faith are outside the scope of the CISG. The governing law regarding to the abovementioned matters is needed.

• 한국의류학회지
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• 제41권1호
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• pp.84-97
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• 2017

Water vapor and thermal transmission properties of high emotional garments are important to evaluate wear comfort; in addition, the measuring methods of these properties are also critical for breathable and warm suit fabrics. In this study, the water vapor and thermal properties of composite yarn fabrics made of CoolMax, Tencel, and Bamboo fibers with filaments were measured and compared according to the measuring method. Water Vapor Transmittance (WVT) of the fabric woven by the sheath/core composite yarn in the warp direction was the highest due to the small staple fiber volume in the sheath/core yarn structure and high air voids in the sheath/core yarn fabrics. This property was also the highest in fabrics woven by bamboo staple yarns in the weft direction, and was the lowest on hi-multi filament fabrics. However, water vapor resistance ($R_{ef}$) of these fabrics by KSK ISO 11092 showed the opposite results to the water vapor transmittance method ($CaCl_2$ method); in addition, its correlation coefficient was low. The correlation coefficient between $R_{ef}$ and the drying rate was 0.719; therefore, the measurement mechanism of $R_{ef}$ is analogous to the drying property measurement. The thermal conductivity of the fabrics woven with compact staple yarn showed a high value; however, the hi-multi filament fabric showed low thermal conductivity. Therefore, fiber characteristics affect thermal properties more than yarn structure. The correlation between thermal property and moisture transport was also low. This study showed that: water vapor transmittance was active at the loose yarn structure, dry heat transport was vigorous at the compact yarn structure, and heat transport was affected more by fiber characteristics than yarn structure. In conclusion, sheath/core composite yarns were relevant to the high absorptive cool suit along with siro-fil and CoolMax/Bamboo staple yarns that were relevant to the heat diffusive cool suit.

• 한국해양환경ㆍ에너지학회지
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• 제14권4호
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• pp.280-286
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• 2011

본 연구에서는 기름에 대한 실리콘의 선택적 반응 현상을 이용하여 해상에 유출된 기름을 탐지하는 방법과 이를 적용한 센서의 특성을 실험적으로 분석한 결과를 제시한다. 기름을 탐지하기 위한 방법으로는 기름과 접촉시 실리콘고무의 부피가 변화되는 성질을 이용하였으며 이를 정량적으로 측정하기 위해서 스트레인 게이지와 실리콘 고무가 결합된 새로운 형태의 센서 코어를 제안하였다. 기름의 종류별 센서 코어의 특성 실험을 통해 유출유 탐지 센서로 사용이 가능함을 확인하였고, 해당 센서의 실해역 적용을 위해서 부이형태의 센서 플랫폼을 센서 코어 및 스트레인 계측기와 통합시켜, 기름 유출이 모사된 조건에서 기름을 탐지하는 실험을 통해 여러 종류의 기름의 존재 유무를 탐지할 수 있는 센서로 활용할 수 있음을 보였다.

• Advances in nano research
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• 제10권5호
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• pp.449-460
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• 2021

Flexoelectricity is an interesting materials' property that is more touchable in small scales. This property beside the sandwich structures placed in the center of scientists' attention due to their extraordinary effects on the mechanical properties. Furthermore, in the passage of decades, more elaborated sandwich structures took into consideration results from using honeycomb core. This kind of structure, inspiring from honeycomb core, provides more stiffness to weight ratio, which plays a crucial role in different industries. In this paper, based on the Love-Kirchhoff's hypothesis, Hamilton's principle, modified couple stress theory and Fourier series analytical method, equations of motion for a sandwich plate containing a honeycomb core integrated by two face-sheets have derived and solved analytically. The equations of both face sheets have derived by flexoelectricity consideration. Moreover, it should be noticed that the whole structure rests on the visco-Pasternak foundation. Conducting current research provided an acceptable and throughout study based on flexoelectricity to address the effect of materials' characteristics, length-scale parameter, aspect, and thickness ratios and boundary conditions on the natural frequency of honeycomb sandwich plates. Also, based on the presented figures and tables, there is a close agreement between previous studies and recent work. Due to the high ratio of strength to weight, current model analyzing is capable of taking into account for different vehicles' manufacturing in a high range of industries.

• 대한한의학회지
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• 제25권3호
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• pp.12-19
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• 2004

Objectives : In the WIPO conference about the protection of intellectual property for traditional knowledge (TK) and genetic resources (GR), there was a demand concerning the necessity of recognizing the invention of TK and GR and the foundation of a related database. Methods : In the standard of the foundation of a database, the content and resource identification standards, the technological standards and the security and transmission standards were discussed. In a decision on intellectual property, it means the protection and recognition as a technology precedent of the materials of the database. Results : Massive material on traditional medical care technology in Korea has existed in many areas. However, it is hard to make a database because it is difficult to organize and find the data. In addition, a database demanded by WIPO is not only the material of images or texts of simple technology information, but also the use of patent decisions about traditional knowledge technology and the public sharing of information in related areas. A traditional medical care database would consist of the core of a subject and the related areas. The core part is the medical herb resource and Oriental clinical technology. Conclusions : These are necessary to detail the kind of medicines and prescriptions, their use, and their processing. In the related areas, it needs to detail PIAS and clinical data in regarding the industrialization. These DB have to protect the TK and the GR of Korea.

• 한국정보통신학회논문지
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• 제13권12호
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• pp.2569-2578
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• 2009

Core-A 마이크로프로세서는 32-bit RISC 구조의 국산 임베디드 마이크로프로세서로서 특허청의 지원을 받아 KAIST의 주관아래 개발된 프로세서이다. 본 논문에서는 Core-A 마이크로프로세서와 코프로세서간의 인터페이스 방안에 대하여 분석하고 효율적인 구조를 제안한다. 인터페이스 방안의 검증을 위해 코프로세서로 사용된 AES 암호 프로세서는 128-bit의 키와 블록을 갖는 대칭키 암호 알고리즘이다. 코프로세서 인터페이스 회로와 AES 암호프로세서는 Verilog-HDL로 작성되었으며, Modelsim 시뮬레이터를 사용하여 시뮬레이션을 수행하였다. 삼성 0.35um CMOS 표준 셀 라이브러리를 사용하여 AES를 제외한 코프로세서 인터페이스 부분을 합성한 결과 약 90Mhz의 동작주파수를 가지며, 3743개의 게이트수로 구성되었다. 본 논문에서 구현한 코프로세서 인터페이스 회로는 Core-A와 코프로세서간의효율적인 명령어 및 데이터 전달을 수행할수있다.