• KSBB Journal
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• v.17 no.3
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• pp.235-240
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• 2002

The surface of polypropylene was modified by 1 keV $Ar^+$ ion beam in an $O_2$ environment in order to enhance wettability. Contact angle of deionized water on modified polypropylene was reduced from $78^{\circ}$to $22^{\circ}$. The enhanced wettability is originated from newly formed functional groups such as ether, carbonyl, and carbonyl groups. During immersion in deionized water, the enhanced wettability has remained nearly same. After washing in water, the hydrophilic functional groups on the polymer surface have been very stable. The modified polypropylene was adopted as bio-film media to remove organics in synthetic wastewater. Microbe adhesion on the polypropylene surface was improved due to the newly formed hydrophilic groups.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.4
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• pp.184-191
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• 2010

Epiphytic diatoms are very important organisms in the seagrass ecosystem because their colonization on leaves increases microtopography and provides attachment sites that make the leaves more hospitable for other epiphytes. Epiphytic diatoms were attached to the leaves in the following 3 manners: (1) parallel to the cells of the seagrass leaf or by molding the shape of the diatom along the cell shape of the leaf; (2) with increasing diatom density toward the leaf tip; (3) Cocconeis species as attaching species than the Naviculoid species as the second attaching species on the leaf tip. In addition, the epiphytic diatom communities on Zostera marina leaves differed from those on the Zostera japonica leaves, but were very similar to the epiphytic communities on Zostera caespitosa leaves. Our results suggest that the epiphytic community on seagrass leaves varied according to the leaf shape such as leaf length and width, but the leaf cell shape or size did not influence the dynamics of the diatom communities.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.1
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• pp.41-51
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• 2006

This paper concerns the effect of lining interface adherence on the lining's load carrying capacity. A series of reduced scale laboratory tests and finite element anlayses were carried out with the aim of gaining insight into the effect of shotcrete lining adherence on the load carrying capacity of double shell lining. The results indicated among other things that the load carrying capacity of a double shell tunnel is significantly affected by the adherence between layers. Also revealed was that for cases with low lining layer adherence stress concentration may occur due to relative movement between the lining layers with this trend being more pronounced with increasing tunnel cover depth. Practical implications from the results of this study are discussed in great detail.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.5
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• pp.544-551
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• 2008

QUAL2K enhanced QUAL2E and applied in real fields efficiently incorporates denitrification process, sediment-water interaction process, bottom algae and detritus. Also, the CBOD of QUAL2K is divided into two real parts, one is slow CBOD(sCBOD) and another is fast CBOD(fCBOD). The simulation results of QUAL2E and QUAL2K models in Anyang Stream were compared and analyzed in water quality constituents of DO, BOD, Org-N, NH$_3$-N, NO$_3$-N, Org-P, Dis-P and Chl-a respectively. The similar results were shown in Org-N, NH$_3$-N, Org-P and Chl-a both QUAL2K and QUAL2E models. But the different results were revealed in DO, BOD, Dis-P and NO$_3$-N by the influence of new incorporating processes. DO was shown relatively low values in the effect of bottom algae. BOD which is influenced by particulate organic matter was revealed high values. NO$_3$-N was closed to the real values by the two processes of denitrification and sediment-water interaction. To evaluate the running results of QUAL2K and QUAL2E models, a simple statistical analysis was conducted. According to the statistical analysis, QUAL2K represented less relative error and coefficient of variation than QUAL2E in almost all of constituents. It was found that QUAL2K, which simulates the water quality more realistically, can be applied to control and manage the water problems of river or river-run reservoir effectively.

• Journal of Periodontal and Implant Science
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• v.25 no.1
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• pp.99-110
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• 1995

치주치료의 궁극적 목표인 치주조직 재생에 대한 관심이 높아지는 가운데 치주조직 재생에 주된 역할을 하는 치주인대세포와 치근면 탈회에 의한 신부착 효과에 관한 많은 연구가 시도되고 있다. 그러나 광범위한 연구에도 불구하고 어떤 치근면 처리가 신부착 형성에 가장 효과적인지는 아직 논란의 대상으로 남아있다. 이에 저자는 결합조직 부착에 의한 재생에 필수적인 치은 및 치주인대 섬유아세포의 부착 및 증식을 tetracycline-HCL(TC)과 citric acid(CA)로 각각 처리된 상아질 표면에서 비교관찰하여 치주조직 재생에의 기여도를 추정하기 위해 본 연구를 시행하였다. 교정치료를 위하여 본원에 내원한 환자의 제일 소구치의 건강한 치은조직을 채취하고, 발치 후 효소처리에 의한 치주인대세포를 얻은 후 각각 세포배양하였다. 상아질 절편은 $3{\times}3{\times}0.2mm^3$로 준비하고 TC과 CA처리군으로 나눈 후 각각 치은 및 치주인대 섬유아세포를 부착시키고 초기부착은 8시간까지, 증식은 7일까지 고나찰하여 다음의 결과를 얻었다. 1. 각 군의 세포 부착은 시간이 지남에 따라 증가되었다. 2. 모든 군에서 7일째 빠른 증식상을 보였다. 3. 초기 부착시 치은과 치주인대 섬유아세포의 반응에는 유의한 차이가 없었다. 4. 반면에 치은과 치주인대 섬유아세포는 증식속도에서 차이를 나타내었으며 치은 섬유아세포가 좀 더 빠른 성장을 보였다. 5. 치근면 탈회에 따라 초기부착과 증식상에서 모두 유의성 있는 증가를 보였다. 6. CA는 초기부착에서, TC는 증식장에서 더욱 효과적으로 작용했다.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.618-624
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• 2002

Effect of the roasted barley tea in commercial markets on the adherence to the saliva-coated hydroxyapatite(HA) beads and the cell surface hydrophobicity of Streptococcus mutans and Streptococcus sobrinus as cariogenic microorganism was examined in vitro. Adherence activity and hydrophobicity in bacteria tested in all the barley tea samples decreased and the values were different according to the type of tea and the type of treatment. The inhibition of bacterial adsorption to HA beads suggest that barley tea active molecules as catechins and melanoidins may adsorb to a host surface, preventing the tooth receptor from interacting with any bacterial adhesions. The obtained results showed that the barley tea may inhibit bacterial adherence, the first step of the pathogenesis of dental caries in which these microorganism are involved.

• Journal of the Korea Concrete Institute
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• v.17 no.3 s.87
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• pp.393-400
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• 2005

Steel encased composite columns have been used for buildings and piers of bridges. Since the column section for the pier is relatively larger than that of building columns, economical steel ratio needs to be investigated for the required performance. Composite action between concrete and embedded steel sections can be obtained by bond and friction. However, the behavior of the column depends on the load introduction mechanism. Compression can be applied to concrete section, steel section and composite section. In this paper, experiments on shear strength of the steel encased composite column were performed to study the effect of confinement by transverse reinforcements, mechanical interlock by holes, and shear connectors. Bond strength obtained from the tests showed considerably higher value than the design value. Confinement, mechanical interlock and stud connectors Increased the shear strength and these values can be used effectively to obtain composite action of Steel Reinforced Concrete(SRC) columns.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.223-225
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• 2007

컨테이너 크레인은 대형구조물로써 차폐물이 거의 없는 항만에 설치되므로 풍하중에 의한 영향이 매우 크다. 또한 초대형 컨테이너선의 등장과 대형선사의 등장과 함께 항만하역장비도 대형화, 고속화, 자동화됨으로써 컨테이너 크레인에 작용되는 풍하중의 영향이 더욱 증가하고 있다. 이로 인하여 컨테이너 크레인은 강풍에 의한 재난사고 발생위험이 항상 존재한다. 이러한 사고를 예방하기 위한 기상 및 하중 통합 모니터링 시스템 장치의 개발이 필요하며, 이러한 장치를 개발하게 되면, 국내외 기존 항만에 사용되고 있는 하역장비에 바로 설치할 수 있으며, 차후 개발되고 있는 자동화된 하역장비에도 적용이 가능함에 따라 관련 산업의 발전에 크게 기여할 수 있을 것이다. 본 논문에서는 이러한 하중 통합 모니터링 시스템의 가장 기본이 되는 컨테이너 크레인의 각 레그(Leg)부분에 부착되는 간접부착식 로드셀의 하중과 치수사이의 관계에 대한 연구를 제시하고자 한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2017.11a
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• pp.952-953
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• 2017

립모션(Leap Motion)은 가상현실 환경의 상호작용 장치로 각광받는 기기이다. 이에 따라 가상현실 출력장치인 HMD에 립모션을 부착해 사용하는 콘텐츠가 늘고 있다. 하지만, 립모션이 HMD상의 부착된 위치가 매번 다르기 때문에, 립모션의 손가락 감지범위와 HMD의 출력 범위가 서로 다르다는 문제점이 있다. 이를 해결하기 위해 본 논문에서는 번들 조정 알고리즘을 이용해 HMD와 립모션의 상대위치를 추정하는 기법을 제안한다. 제안하는 기법을 통해 HMD와 립모션을 부착해 이용하는 콘텐츠에 전처리기로 활용할 수 있을 전망이다.

• 한국HCI학회:학술대회논문집
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• 2008.02b
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• pp.257-261
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• 2008

In this paper, intuitive interactions compatible with various software and replaceable with the conventional mouse function are proposed for camera-tracked laser pointer system. For this purpose, this paper designs the motion based interaction using acceleration information from a new laser pointer with 3-axes accelerometer and shows its usability.