• Title/Summary/Keyword: 구조벽

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Regenerative Endodontic Treatment of Infected Immature Permanent Teeth with Dens Invaginatus : A Report of Two Cases (치내치를 동반한 감염된 미성숙 영구치의 재생형 근관치료)

  • Shin, Gayoung;Lee, Kwanghee;An, Soyoun;Song, Jihyun;Heo, Narang;Ra, Jiyoung
    • Journal of the korean academy of Pediatric Dentistry
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    • v.42 no.2
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    • pp.188-196
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    • 2015
  • Endodontic management of an immature permanent tooth with dens invaginatus poses a challenge to efficient treatment planning for the clinicians. Because it is difficult to shape, disinfect, and seal the canal space effectively, teeth with complex root canal structures often require particularly extensive and thorough treatment approaches. The purpose of this case report was to share clinical insight from the results of short-term follow-ups after regenerative endodontic treatment with a dens invaginatus. Two immature maxillary lateral incisors with Oehlers type I and III dens invaginatus and infected necrotic pulp were treated using regenerative endodontic procedures. For the type III dens invaginatus case, an unusual approach toward redesigning the complex internal structure was taken, in order to have sufficient infection control and sealing. Cone-beam computed tomography (CBCT) and a surgical operating microscope were used to aid visualization and treatment. As a result, regenerative endodontic treatment appears to be effective for managing immature permanent teeth with complex dens invaginatus, and can lead not only to clinical and radiographic resolution, but also increased thickness of the dentinal walls.

Quality Characteristics of Citrus Fruit by Cyclic Low Pressure Drying and High Hydrostatic Pressure Extraction (초고압 처리에 의한 감귤의 추출률 및 특성변화)

  • Park, Sung-Jin;Choi, Young-Bum;Ko, Jung-Rim;Rha, Young-Ah;Lee, Hyeon-Yong
    • Culinary science and hospitality research
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    • v.20 no.3
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    • pp.13-21
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    • 2014
  • We developed a method for improving the antioxidant activities of Citrus extracts through cyclic low pressure drying(CLPD) and a high hydrostatic pressure extraction (HPE) process. Citrus fruits were prepared for water extraction at $60^{\circ}C$ and 300 MPa for 5 min (high hydrostatic pressure extraction, HPE5) and 15 min (high hydrostatic pressure extraction, HPE15) after cyclic low pressure drying method. Extraction yields obtained by cyclic low pressure drying and high hydrostatic pressure extraction process were 20.41, 23.47, and 28.19%, respectively. Total polyphenol contents were increased by combined process. Generally, CLPD and HPE resulted in higher yields than the conventional extraction process. Further, HPE15 showed 48.21% DPPH radical scavenging activity (EDA, %) at $1,000{\mu}g/mL$. In general, antioxidant activities of Citrus increased by CLPD and HPE. Therfore, CLPD and HPE of Citrus resulted in higher antioxidant activity than conventional water extraction.

An Experimental Study on the Settlement Characteristics of the Corner of Earth Retaining Wall According to the Ground Excavation (지반굴착에 따른 흙막이벽 우각부 모서리 구간의 침하특성에 대한 실험 연구)

  • Yoon, Won-Sub;Cho, Chul-Hyun;Cho, Young-Kweon;Chae, Young-Su
    • Journal of the Korean Geosynthetics Society
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    • v.12 no.2
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    • pp.55-66
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    • 2013
  • The experiment of model soil structures has been executed for the soil retaining wall in various conditions of excavation, in this study, to analyze the behavior of the corner of opening. The ground for experiment has been constituted with the sandy soil of relatively loose density, the construction condition has been divided into the opening length of corner, embedded depth, existence of strut, etc., and the excavation has been carried out for 4 stages in total. The behavior characteristics at the corner of opening area has been verified by concentrate analysis of the displacement of wall and the subsidence of ground surface, for each construction and excavation condition, using the measuring instrument mounted inside the model soil structure. In the result of experiment, it has been analyzed that the opening area of corner is unstable structurally compared to the linear area, as it shows that the wall displacement and subsidence of ground surface have been increased when the opening length of corner gets longer. The longer the embedded depth, ground surface settlement of coner was decreased 40%. To apply deeper embedded depth than designed estimate was an advantage in the safety. As a result of the analysis of coner behavior with added struts, maximum surface settlement and maximum horizontal displacement was evaluated 40% and 30%, respectively. Hence increased embedded depth with the added struts in coner edge was effective in the safety.

An Overview on the Physicochemical Properties and Photocatalytic Pollutant Removal Performances of TiO2-incorporated Cementitious Composites (TiO2 혼입 시멘트 복합체의 물리·화학적 특성 및 광촉매 반응을 이용한 오염물 제거 성능에 대한 개요)

  • Seo, J.H.;Yoon, H.N.;Kim, S.H.;Bae, S.J.;Jang, D.I.;Kil, T.G.;Park, S.M.;Lee, H.K.
    • Composites Research
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    • v.33 no.2
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    • pp.68-75
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    • 2020
  • Recently, the use of TiO2 as a phtocatalyst has been diversely investigated due to its excellent durability performance and high photocatalytic reaction efficiency. Active researches have particularly focused on the development of TiO2-incorporated cementitious composites in order to remove the atmospheric pollutants. Furthermore, the potential utilization of TiO2-incorporated cementitious composites as road accessories such as tunnels, road median separators and soundproof walls in the form of tiles, blocks and structural components has been widely examined. In this regard, a thorough understanding on the material characteristics of TiO2-incorporated cementitious composites should be preceded. The present overview article, therefore, revisits previous studies of TiO2-incorporated cementitious composites and summarizes their various physicochemical properties and atmospheric pollutants removal performance.

The Design And Implementation of Robot Training Kit for Java Programming Learning (Java 프로그래밍 학습을 위한 로봇 트레이닝키트의 설계 및 구현)

  • Baek, Jeong-Hyun
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.10
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    • pp.97-107
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    • 2013
  • The latest programming paradigm has been mostly geared toward object-oriented programming and visual programming based on the object-oriented programming. However, object-oriented programming has a more difficult and complicated concept compared with that of existing structural programming technique; thus it has been very difficult to educate students in the IT-related department. This study designed and implemented a Java robot training kit in which the Java virtual machine is built so that it may enhance the desire and motivation of students for learning the object-oriented programming using the training kit which is possible to attach various input and output devices and to control a robot. The developed Java robot training kit is able to communicate with a computer through the USB interface, and it also enables learners to manufacture a robot for education and to practice applied programming because there is a general purpose input and output port inside the kit, through which diverse input and output devices, DC motor, and servo motor can be operated. Accordingly, facing the IT fusion era, the wall between the academic circles and the major becomes lower and the need for introducing education about creative engineering object-oriented programming language is emerging. At this point, the Java robot training kit developed in this study is expected to make a great commitment in this regard.

Synthesis of Mesoporous Silica Using Municipal Solid Waste Incinerator Ash Slag : Influence of NaOH Concentration (생활(生活) 폐기물(廢棄物) 소각재(燒却材) 슬래그를 이용(利用)한 메조포러스 실리카 합성(合成) : NaOH 농도(濃度)의 영향(影響))

  • Han, Yo-Sep;Jung, Jong-Hoon;Park, Jai-Koo
    • Resources Recycling
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    • v.19 no.1
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    • pp.40-48
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    • 2010
  • It was investigated that effects of NaOH concentration on synthesis of mesoporous materials using municipal solid waste incinerator ash slag (MSWI-ash slag). In order to increase the purity and maximize the amount of extracted Si content the raw MSWI-ash slag was mechanically activated. Extraction of Si from the MSWI-ash slag was carried out by alkali treatment using concentrated NaOH solution, which varied from 1M to 4M. Physical properties (i.e., pore size, specific surface area and total pore volume) of the synthesized mesoporous silica were also evaluated as a function of NaOH concentration via BET, SEM, TEM and small-angle X-ray scattering analyses. Over the entire range of NaOH concentration investigated (i.e., 1-4M), the synthesized mesoporous materials were determined to be SBA-15, which exhibited a hexagonal structure with the pore size of approximately 7 nm. On the other hand, specific surface area and total pore volume increased with NaOH concentration up to 3M while the values decreased at 4M, indicating that the optimal NaOH concentration for the synthesized mesoporous silica was approximately 3M. Further comparison analysis between two conditions (3M versus 4M) showed that the decrease in two physical properties at 4M NaOH concentration was likely due to the potential inhibition by excess Na ions on the formation of mesophase and the consequent increase of pore wall thickness by remaining Si ions.

A Study on Survivability of Node using Response Mechanism in Active Network Environment (액티브 네트워크 환경에서 대응 메커니즘을 이용한 노드 생존성에 관한 연구)

  • Yang, Jin-Seok;Lee, Ho-Jae;Chang, Beom-Hwan;Kim, Hyoun-Ku;Han, Young-Ju;Chung, Tai-Myoung
    • The KIPS Transactions:PartC
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    • v.10C no.6
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    • pp.799-808
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    • 2003
  • Existing security solutions such as Firewell and IDS (Intrusion Detection System) have a trouble in getting accurate detection rate about new attack and can not block interior attack. That is, existing securuty solutions have various shortcomings. Shortcomings of these security solutions can be supplemented with mechanism which guarantees an availability of systems. The mechanism which guarantees the survivability of node is various, we approachintrusion telerance using real time response mechanism. The monitoring code monitors related resources of system for survivability of vulnerable systm continuously. When realted resources exceed threshold, monitoring and response code is deployed to run. These mechanism guarantees the availability of system. We propose control mathod about resource monitoring. The monitoring code operates with this method. The response code may be resident in active node for availability or execute a job when a request is occurred. We suggest the node survivability mechanism that integrates the intrusion tolerance mechanism that complements the problems of existing security solutions. The mechanism takes asvantage of the automated service distribution supported by Active Network infrastructure instead of passive solutions. The mechanism takes advantage of the automated service distribution supported by Active Network infrastructure instead of passive system reconfiguration and patch.

Volatile Compounds and Ultrastructure of Petal Epidermal Cells According to Scent Intensity in Rosa hybrida (장미꽃의 향기정도에 따른 주요성분 및 꽃잎 세포의 미세구조)

  • Lee, Young-Soon;Lee, Yun-Hae;Lim, Seung-Hee;Park, Gun-Hwan;Choi, Sunk-Young;Hong, Hae-Jung;Ko, Jeong-Ae
    • Horticultural Science & Technology
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    • v.31 no.5
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    • pp.590-597
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    • 2013
  • Principle component and emission localization of volatile compounds were investigated according to scent intensity of rose flower. Scent intensity in cultivars and bred-line of Rosa hybrida was divided into three levels; light ('Feel Lip', 'Venus Berry'), medium ('GR07-135'), strong ('Honey Blue'). The major volatile compounds were different depending on the cultivars and selected line; 3,5-dimethoxytoluene (DMT), benzene, 1,3,5-trimethoxy ('Feel Lip'), megastigma-4,6(Z),8(E)-triene ('Venus Berry'), DMT, benzene,1-ethenyl-4-methoxyand, phenylethylalcohol ('GR07-135') and germacrene-D, DMT ('Honey Blue'). The adaxial epidermal cells were conical papillate shape, whereas the abaxial epidermal cells were flat shape. The adaxial epidermal cells of 3 cultivars and 1 selected line were surrounded by thick cell wall and covered by waxy cuticle of 2 cultivars and 1 selected line (except 'Honey Blue'). The adaxial epidermal cells contained starches in 'Feel Lip', osmiophlic droplets in 'Venus Berry', starchs, plastids, vacuoles in 'GR07-135' and plastoglobules, plastids, vacuoles in 'Honey Blue'. Based on these results, it appears that plastids and vacuoles in adaxial epidermal cells with conical papillate shape are associated production and emission of volatile compounds in scent R. hybrida.

Extraction and Physicochemical Characterization of Barley Bran $\beta$-glucan (보리겨 $\beta$-glucan의 추출 및 이화학적 특성)

  • 김선영;유정희
    • Korean journal of food and cookery science
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    • v.19 no.5
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    • pp.616-623
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    • 2003
  • Waxy barley brans were collected during the pearling process. The extraction of $\beta$-glucan from barley bran was effected by the extraction conditions. The $\beta$-glucan content increased with temperature, but not with pH. The highest yield, 6.5%, was achieved at pH 7.0 and 55$^{\circ}C$. At pH 10 and 45$^{\circ}C$, 48.5% of the $\beta$-glucan in barley bran was recovered in the gum product, with 54.6% purity. The protein and starch contaminations were high, reaching 13.6 and 23.7%, respectively. The $\beta$-glucan content was greatest in the subaleurone and aleurone regions (bran fractions 1, 2, 3 and 4), and declined considerably toward the inner layers. A monosaccharide analysis of the purified, $\beta$-glucan, from bran fractions 1, 2, 3 and 4, indicated that glucose constituted the majority of the gum. The small amounts of the arabinose and xylose found in the gum may indicate the presence of arabinoxylans as minor constituents. The molecular weights of the $\beta$-glucans isolated from bran fractions 1,2 and 3 were found to be 4.09${\times}$10$^{5}$ ∼-4.41${\times}$10$^{5}$ . The major glycosidic linkages of the $\beta$-glucans demonstrated the presence of 2, 4, 6-Me-Glc and 2, 3, 6-Me-Glc. When flow behaviors of barley bran $\beta$-glucan were examined, $\beta$-glucan exhibited pseudoplastic fluid properties.

Bed Design of Inducement Nets for Chrysanthemum Cultivation (국화재배용 유인네트의 베드 설계)

  • Suh, Won-Myung;Kim, Young-Ju;Bae, Yong-Han;Min, Young-Bong;Park, Joong-Choon;Huh, Moo-Ryong;Yoon, Yong-Cheol
    • Journal of agriculture & life science
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    • v.43 no.2
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    • pp.47-53
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    • 2009
  • This research is intended to study the induction net of chrysanthemum used in its greenhouse and requiring lots of time for manual work and review the structural safety of a bed and existing greenhouses after designing the bed of a net which increases cropping period by sharply reducing the time of work and provides the bed of induction nets for cultivating chrysanthemum with its existing and new greenhouse. The review of sectional and biodynamic properties in 15 kinds of materials has revealed that the pipes of ${\phi}38.1{\times}1.7t$and ${\phi}38.1{\times}2.0t$ didn't exceed stress ratio but did 10mm drooping allowance. For this reason, the pipe of ${\phi}48.1{\times}1.5t$ net both stress ratio and drooping allowance. For the safety, the middle chamber should be designed into Truss type owing to bed load, wind load, and snow load when the bed of an induction net is installed in the middle chamber. When installing the middle chamber with a truss type, the greenhouse of chrysanthemum in Geochang area needs proper reinforcements because the stress in colullllls and wind proof walls exceeds stress allowance regardless of the installation of a bed.