• Proceedings of the Materials Research Society of Korea Conference
• /
• 2009.05a
• /
• pp.48.1-48.1
• /
• 2009

Ti합금은 생체적합성이 우수하여 생체재료로 널리 사용되어 왔으며, 특히 Nitinol로 알려진 Ti-Ni합금은 형상기억특성 및 초탄성특성을 지녀 치열교정용 와이어나 혈관확장용 스텐트 등으로 사용되어 왔다. 최근 Ni과 같은 세포독성 합금원소의 용출가능성이 문제가 되어 Ni을 함유하지 않는 Ti합금이 주목받고 있다. 본 연구에서는 Ti-Nb-Ge 합금의 집합조직과 초탄성 및 기계적 특성의 관계를 고찰함으로써, 사용목적이나 요구특성에 부합되는 가공열처리방법을 도출하고자 하였다. 비소모전극식 진공아크용해장치를 이용하여 Ti-Nb-Ge 합금 버튼을 만들고, 이를 $1000^{\circ}C$에서 30분간 유지 후 얼음물에 급랭처리하였다. 이후 집합조직 제어를 위해 등속압연 및 이속압연의 두가지 방법으로 냉간압연한 후, $850^{\circ}C$에서 30분~2시간까지 열처리하였다. 광학현미경과 투과전자현미경을 이용하여 미세조직을 관찰하고, X-선 회절분석법을 이용하여 집합조직을 분석하였다. 또한 순환식 인장시험을 통해 시편의 초탄성 특성 및 기계적 성질을 평가하였다. 등속압연재는 {001}<110>에서 {111}<110>에 이르는 $\alpha$-fiber가 발달하는 한편, 이속압연재는 {001} 및 {111}가 발달하는 것으로 나타났다. 또한 압연방향으로 <110>이 평행한 집합조직이 발달할수록 초탄성 특성이 높게 나타났다. 이는 응력유기 마르텐사이트 변태 시 $\beta$의 <110>방향이 $\alpha$" <010>방향으로 변할 때 길이가 증가하므로, 시편에 인장방향으로 <110>이 평행한 집합조직이 발달할수록 응력유기 마르텐사이트 변태가 용이해지기 때문인 것으로 사료된다.

• Polymer(Korea)
• /
• v.31 no.6
• /
• pp.518-525
• /
• 2007

The thermomechanical properties and morphologies of nanocomposite fibers of poly(ethylene terephthalate)(PET) incorporating thermally stable organoclays are compared. Dodecyltriphenyl-phosphonium-mica($C_{12}PPh-Mica$) and 1-hexadecane benzimidazole-mica ($C_{16}BIMD-Mica$) were used as reinforcing fillers in the fabrication of PET hybrid fibers. Dispersions of organoclays with PET were studied by using the in-situ polymerization method at various organoclay contents to produce nano-scale composites. The thermo-mechanical properties and morphologies of the PET hybrid fibers were determined using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide angle X-ray diffraction (XRD), electron microscopy (SEM and TEM), and a universal tensile machine (UTM). Transmission electron microscopy (TEM) micrographs show that some of the clay layers are dispersed homogeneously within the polymer matrix on the nano-scale, although some clay particles are agglomerated. We also found that the addition of only a small amount of organoclay is enough to improve the thermal stabilities and mechanical properties of the PET nanocomposite fibers. Even polymers with low organoclay content (<5 wt%) were found to exhibit much higher thermo-mechanical values than pure PET fibers.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.19 no.1
• /
• pp.1-7
• /
• 2014

Butyltin compounds (BTs) were determined in surface sediment samples from Ulsan Bay in 2009 and 2011, to assess the contamination status and the effectiveness of tributylin (TBT) restriction of Korea. Dibutyltin and TBT concentrations in sediments in 2011 ranged from 19.5 to 980 and 14.2 to 1204 ng Sn $g^{-1}$ dry weight, respectively. The highest TBT concentration was found in a big shipyard complex and the next highest was found in harbor, suggesting that harbor and shipyard activities are a major contamination source of TBT in Ulsan Bay. Concentrations of BTs in Ulsan Bay sediments were significantly lower in 2009 and 2011 than that in 2003 survey previously reported, probably as a consequence of the legislative action in Korea. However, TBT concentrations in sediments still exceeded ecotoxicological values. Therefore, it will be important to monitor and reduce TBT contamination in sediments until the levels fall well below ecotoxicological levels.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2012.11a
• /
• pp.57-59
• /
• 2012

본 논문에서는 소형 임베디드 시스템을 응용하여 원격으로 가정의 에너지를 효율적으로 절약할 수 있는 시스템을 제안한다. 이를 위하여 OpenWrt기반 소형 유무선 공유기를 임베디드 시스템 개발 플랫폼으로 활용하여, DC 모터가 장착된 창문 블라인드를 날씨 변화에 따라 원격지에서 스마트폰으로 제어가 가능하게 하였다. 프로토타입 시스템 구현은 Buffalo사의 WZR-HP-G450H 유무선공유기, Arduino 사의 UNO 인터페이스 보드, DC 모터로 구성하였다. 원격제어 시스템은 iOS 기반으로 애플리케이션을 제작하였다. 전체 시스템의 동작 검증은 스마트폰과 유무선 공유기, 인터페이스 보드의 소켓통신을 통하여 DC 모터의 속도를 원격으로 조절함으로 동작을 확인하였다.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.4
• /
• pp.513-518
• /
• 2005

Volatile compounds of $\gamma-irradiation$ leeks (Aillum tuberosum R.) were isolated by simultaneous steam distillation and extraction method (SDE) and analyzed by gas chromatography/mass spectrometry (GC/MS) along with the non-irradiated sample. Leeks were irradiated at dose of 20 kGy and non-irradiated samples were considered as control sample. 56 and 54 compounds were identified in non-irradiated and irradiated samples, respectively. These components included the functional groups; alcohols, aldehydes, esters, ketones, N- and S-containing compounds. S-containing compounds such as dimethyl trisulfide, methyl-(Z)-l-proenyl trisulfide, dimethyl disulfide, 3-ethyl-l,2-dithi-5-ene and methyl allyl disulfide were the major compounds. Methyl-(Z)-l-propenyl trisulfide, diallyl trisulfide, (E)-2-hexanal and 3-ethyl-l,2-dithi-5-ene were clearly decreased by the $\gamma-irradiation$, but dimethyl disulfide, diallyl sulfide, allyl methyl sulfide and pyridine were increased by the $\gamma-irradiation$.

• Polymer(Korea)
• /
• v.38 no.1
• /
• pp.38-42
• /
• 2014

The poly[(9,9-bis((6'-(N,N,N-trimethylammonium)hexyl)-2,7-fluorene)-alt-(9,9-bis(2-(2-(2-methoxyethoxy)ethoxy)ethyl)-9-fluorene)) dibromide (WPF-6-oxy-F)] and graphene oxide (GO) was blended and irradiated with gamma ray under ambient condition. This WPF-6-oxy-F-GO composite was investigated as a hole-transporting layer (HTL) in organic solar cells (OSCs). Compared with the pristine GO, the sheet resistance ($R_{sheet}$) of irradiated WPF-6-oxy-F-GO was decreased about 2 orders of magnitude. The reason for the decrease of $R_{sheet}$ is the effect of efficient ${\pi}-{\pi}$ packing resulted from the formation of C-N bond between WPF6-oxy-F and GO. As a result, the efficiency of OSCs was dramatically enhanced ~ 6.10% by introducing irradiated WPF-6-oxy-F-GO as a HTL. WPF-6-oxy-F-GO is a sufficient candidate for HTL to facilitate the low-cost and high efficiency OSCs.

• Journal of Animal Environmental Science
• /
• v.18 no.sup
• /
• pp.81-90
• /
• 2012

This study was evaluated high end research grade Near infrared spectrophotometer (NIRS) to low end popular field grade multiple Near infrared spectrophotometer (NIRS) for rapid analysis at forage quality at sight with 241 samples of Italian ryegrass silage during 3 years collected whole country for evaluate accuracy and precision between instruments. Firstly collected and build database high end research grade NIRS using with Unity Scientific Model 2500X (650 nm~2,500 nm) then trim and fit to low end popular field grade NIRS with Unity Scientific Model 1400 (1,400 nm~2,400 nm) then build and create calibration, transfer calibration with special transfer algorithm. The result between instruments was 0.000%~0.343% differences, rapidly analysis for chemical constituents, NDF, ADF, and crude protein, crude ash and fermentation parameter such as moisture, pH and lactic acid, finally forage quality parameter, TDN, DMI, RFV within 5 minutes at sight and the result equivalent with laboratory data. Nevertheless during 3 years collected samples for build calibration was organic samples that make differentiate by local or yearly bases etc. This strongly suggest population evaluation technique needed and constantly update calibration and maintenance calibration to proper handling database accumulation and spread out by knowledgable control laboratory analysis and reflect calibration update such as powerful control center needed for long lasting usage of forage analysis with NIRS at sight. Especially the agriculture products such as forage will continuously changes that made easily find out the changes and update routinely, if not near future NIRS was worthless due to those changes. Many research related NIRS was shortly study not long term study that made not well using NIRS, so the system needed check simple and instantly using with local language supported signal methods Global Distance (GD) and Neighbour Distance (ND) algorithm. Finally the multiple popular field grades instruments should be the same results not only between research grade instruments but also between multiple popular field grade instruments that needed easily transfer calibration and maintenance between instruments via internet networking techniques.

• Journal of the Korean Society of Costume
• /
• v.59 no.10
• /
• pp.98-110
• /
• 2009

This study has outlined and summarized academic meaning of formative characteristics of Organic Modernism represented by various aspects of design, art, industry and architecture, then has intented to define concept of Organic Modernism Fashion. Eventually, this study is to make a analysis of formative characteristics of Organic Modernism Fashion Design. Based on example of Organic Modernism applied to architectural structure, industrial products and pure paintings, this study has analyzed and researched into formative characteristics of Organic Modernism represented by fashion design. As a consequence of study, its characteristics are defined as below; The first, the beauty of simple formation using delicate curve. The second, the expression of symbolic formation based on surrealism. The third, the expression of continuous 3-dimensional curved surface. And the last characteristic is a providing transformable multi-function. Through those characteristics mentioned above, it may be expected to define a concept of Organic Modernism Fashion Design newly and to set a precedent for providing a basic criteria to classify formative characteristics of Organic Modernism Fashion Design.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.05a
• /
• pp.724-727
• /
• 2014

This paper is analyzing the situation of the Internet of Things Industry and draw the policy implications to promote Internet of Things industry. Major IT companies as Apple, Google, IBM, Sony, and Samsung have developed various smart glass and smart watch as a Iot products. In order to promote Iot Industry, we should take the build up of eco system between IT makers and the various contents provider, protection of personal information and data, development of killer applications and business models, and the conversion from IPv4 to IPv6 as a next internet address infra, build up of international standard platform on IoT.

• Journal of the Economic Geographical Society of Korea
• /
• v.19 no.1
• /
• pp.18-32
• /
• 2016

In the Hyper-connected society, each country set up its own policy and central government as well as provincial government makes a basic plan of developing IoT. Gyeonggi provincial government needs to cope actively with the changing international and national circumstances. The purpose of this paper is to frame policy as a provincial government with analysis IoT industry-academia-institute-governments ecosystem and in-depth interview. There are IoT related SMEs in Gyeonggi, especially manufacturing business and device fields. Universities are doing IoT researches by R&D funds from central as well as provincial governments. Central government-affiliated Institutions are researching. It is necessary for Gyeonggi provincial government to establish policy in order to actively operate IoT ecosystem while each innovation actors are cooperated in doing IoT; system/governce maintenance, environments and test-bed for the application.