• Title/Summary/Keyword: ABB

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Demineralized dentin matrix combined with recombinant human bone morphogenetic protein-2 in rabbit calvarial defects

  • Um, In-Woong;Hwang, Suk-Hyun;Kim, Young-Kyun;Kim, Moon-Young;Jun, Sang-Ho;Ryu, Jae-Jun;Jang, Hyon-Seok
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.42 no.2
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    • pp.90-98
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    • 2016
  • Objectives: The aim of this study was to compare the osteogenic effects of demineralized dentin matrix (DDM) combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) in rabbit calvarial defects with DDM and anorganic bovine bone (ABB) combined with rhBMP-2. Materials and Methods: Four round defects with 8-mm diameters were created in each rabbit calvaria. Each defect was treated with one of the following: 1) DDM, 2) ABB/rhBMP-2, or 3) DDM/rhBMP-2. The rhBMP-2 was combined with DDM and ABB according to a stepwise dry and dip lyophilizing protocol. Histological and microcomputed tomography (${\mu}CT$) analyses were performed to measure the amount of bone formation and bone volume after 2- and 8-week healing intervals. Results: Upon histological observation at two weeks, the DDM and ABB/rhBMP-2 groups showed osteoconductive bone formation, while the DDM/rhBMP-2 group showed osteoconductive and osteoinductive bone formation. New bone formation was higher in DDM/rhBMP-2, DDM and ABB decreasing order. The amounts of bone formation were very similar at two weeks; however, at eight weeks, the DDM/rhBMP-2 group showed a twofold greater amount of bone formation compared to the DDM and ABB/rhBMP-2 groups. The ${\mu}CT$ analysis showed markedly increased bone volume in the DDM/rhBMP-2 group at eight weeks compared with that of the DDM group. Notably, there was a slight decrease in bone volume in the ABB/rhBMP-2 group at eight weeks. There were no significant differences among the DDM, ABB/rhBMP-2, and DDM/rhBMP-2 groups at two or eight weeks. Conclusion: Within the limitations of this study, DDM appears to be a suitable carrier for rhBMP-2 in orthotopic sites.

A Study on Bubble Behavior Generated by an Air-driven Ejector for ABB (Air Bubble Barrier) (II): Comparison of Bubble Behavior with and without Ejector (공기구동 이젝터를 이용한 ABB (Air Bubble Barrier)의 기포거동 특성 연구 (II): 기포거동 특성의 비교 분석)

  • Seo, Hyunduk;Aliyu, Aliyu Musa;Kim, Hyogeum;Kim, Kyung Chun
    • Journal of the Korean Society of Visualization
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    • v.15 no.2
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    • pp.59-67
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    • 2017
  • To verify floatability of ABB (Air bubble barrier), we compared bubble swarm behavior with and without the air-driven ejector. Experiment was conducted using the fabricated air-driven ejector with 5 mm nozzle on the bottom of 1 m3 water tank. Reynolds number of air in the nozzle was ranged 1766-13248. We analyzed data with statistical method using image processing, particle mage velocimetry (PIV) and proper orthogonal decomposition (POD) analysis. As a result of POD analysis, there was no significant eigenmode in bubbly flow generated from the ejector. It means that more complex turbulent flows were formed by the ejector, thereby (1) making bubbles finer, (2) promoting three-dimensional energy transfer between bubble and water, and (3) making evenly distributed velocity profile of water. It is concluded that the air-driven ejector could enhance the performance of ABB.

RCS Overpressure Protection Analysis Using SEBIM POSRV (SEBIM POSRV를 이용한 원자로 냉각재계통의 과압보호 해석)

  • Kim, Chong-Hoon;Seo, Jong-Tae
    • Nuclear Engineering and Technology
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    • v.27 no.2
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    • pp.165-175
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    • 1995
  • The overpressure protection system for PWR should be designed with sufficient capacity to limit the pressure to less than 110% of the reactor coolant system design pressure during the most severe abnormal operational transient. In this study, the feasibility of adopting the SEBIM POSRV instead of the current spring loaded pop-opening safety valves to the ABB-CE designed 2825 MWt PWR is investigated for its overpressure protection capability. The required SEBIM POSRV size as well as its opening/closing setpoints are determined through a series of computer analyses using the LTC code which has been used for the overpressure protection analysis for Yonggwang units 3&4. The analysis results show that the overpressure protection system with monobloc SEBIM POS-RV can maintain the RCS pressure below 110% of the design pressure demonstrating its overpressure protection capability for the ABB-CE designed 2825 MWt PWRs.

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Tomographic and histometric analysis of autogenous bone block and synthetic hydroxyapatite block grafts without rigid fixation on rabbit calvaria

  • Bae, Soo-Yong;Park, Jung-Chul;Shin, Hyun-Seung;Lee, Yong-Keun;Choi, Seong-Ho;Jung, Ui-Won
    • Journal of Periodontal and Implant Science
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    • v.44 no.5
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    • pp.251-258
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    • 2014
  • Purpose: The preferred material for bone augmentation beyond the envelope of skeletal bone is the bone block graft, due to its dimensional stability. We evaluated the necessity of rigid fixation for the bone block graft, and compared the bone regeneration and volume maintenance associated with grafting using a synthetic hydroxyapatite block (HAB) and an autogenous bone block (ABB) without rigid fixation on rabbit calvaria over two different periods. Methods: Cylinder-shaped synthetic HAB and ABB were positioned without fixation on the rabbit calvarium (n=16). The animals were sacrificed at 4 or 8 weeks postoperatively, and the grafted materials were analyzed at each healing period using microcomputed tomography and histologic evaluation. Results: Integration of the graft and the recipient bed was observed in all specimens, although minor dislocation of the graft materials from the original position was evident in some specimens (six ABB and ten HAB samples). A tendency toward progressive bone resorption was observed in the grafted ABB but not in the grafted HAB, which maintained an intact appearance. In the HAB group, the area of new bone increased between 4 and 8 weeks postoperatively, but the difference was not statistically significant. Conclusions: The nonfixed HAB was successfully integrated into the recipient bed after both healing periods in the rabbit calvaria. In spite of limited bone formation activity in comparison to ABB, HAB may be a favorable substitute osteoconductive bone material.

Process Modeling of Flexible Robotic Grinding

  • Wang, Jianjun;Sun, Yunquan;Gan, zhongxue;Kazerounian, Kazem
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.700-705
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    • 2003
  • In this paper, an extended process model is proposed for the application of flexible belt grinding equipment as utilized in robotic grinding. The analytical and experimental results corresponding to grinding force, material removal rate (MRR) and contact area in the robotic grinding shows the difference between the conventional grinding and the flexible robotic grinding. The process model representing the relationship between the material removal and the normal force acting at the contact area has been applied to robotic programming and control. The application of the developed model in blade grinding demonstrates the effectiveness of proposed process model.

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In-Process Relative Robot WorkCell Calibration

  • Wang, Jianjun;Sun, Yunquan;Gan, zhongxue
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.269-272
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    • 2003
  • Industry is now seeing a dramatic increase in robot simulation and off-line programming. In order to use off-line programming effectively, the simulated workcell has to be identical to the real workcell. This requires an efficient and accurate method for the workcell calibration. Currently used techniques in the industry, however, are typically time-consuming, expensive and therefore not suitable for in-process application. This is because most of these techniques are based on the so-called “absolute calibration” method. In contrast to absolute method, relative calibration only measures the difference of an interested object relative to a standard reference. Owing to the small measurement range requirement, relative calibration method is very cheap and can achieve very high accuracy. In this paper the relative method is applied to calibrate an entire grinding workcell. Linear gauge is the only measurement device used. This workcell calibration includes tool center point (TCP) calibration and work object frame calibration. Due to the efficiency of the calibration algorithm and the simplicity of the calibration setup, the described calibration procedure can be done in process.

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Cytogenetic Studies of Scilla sciloides complex from Korea II. Distribution of Genomes in Chejudo Populations (한국산 무릇(Scilla scilloides complex)의 세포유전학적 연구 II. 제주도 집단에서 게놈의 분포)

  • 방재욱
    • Journal of Plant Biology
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    • v.34 no.2
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    • pp.145-150
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    • 1991
  • 제주도에서 서식하고 있는 무릇의 게놈 분포와 B염색체의 출현 빈도를 조사하였다. 게놈의 유형은 BB, ABB, ABBB, AABB, AABBB 및 AAABBB의 6가지로 나타났으며, 그 중 BB, ABB 및 AAABBB게놈 식물은 제주도 집단에서 처음으로 발견하여 보고되는 것이다. 게놈의 분포는 AABB가 66.2%로 가장 높게 나타났으며, ABBB게놈이 20.4%로 그 다음이었다. ABB와 AAABB게놈 식물은 한 개체씩만 발견되었다. 게놈의 조성은 조사된 13개 집단 중 세가지 유형이 혼생하는 집단이 2개, 두 가지 유형이 나타나는 집단이 BB, AABB 또는 AABBB 중 한 가지 유형의 게놈 식물이 분포하고 있었다. 게놈의 조성으로 보아 제주도의 무릇 집단은 한반도 내륙보다는 일본 집단과의 유연 관계가 더 가까운 것으로 생각된다. B염색체의 수는 1-4개로 나타났으며, 모두 등완염색체(F)였다. B염색체의 출현 빈도는 BB와 AABBB게놈 식물에서 각각 75%로 가장 높게 나타났으며, AABB게놈 식물에서는 48%로 나타나 한반도 내륙(44%)과 비슷한 양상을 보였다. A게놈에 비해 B게놈의 수를 많이 지닌 식물에서 B염색체의 빈도가 높게 나타나는 것이 특징으로 나타났다.

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EXAMINING THE BOUNDARIES OF INSTRUMENT-TO-INSTRUMENT CALIBRATION TRANSPORT

  • Kester, Michael D.;Baudais, Fred L.;Simpson, Michael B.
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1191-1191
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    • 2001
  • Generation of precise, accurate, and robust calibration models for spectroscopic methods of analysis can be time-consuming, expensive, and sometimes difficult to achieve. For these reasons, efforts have been made to find ways in which the calibration from one instrument can be moved to another with minimal performance reduction. A slight shift in nomenclature from the common term calibration transfer to the term calibration transport is used here to help resolve the subtle difference between two means of moving a calibration from one instrument to another. The former term denotes a transfer procedure that includes mathematical manipulation of the calibration data via some determined transfer function, whereas the latter term does not. Todays generation of process and laboratory FTNIR analyzers is capable of not only achieving calibration transfer, but also calibration transport often without the need of slope or bias adjustments. Several studies are used to examine the boundaries of the extent to which calibration transport is achieved in the refining industry. Data collected on multiple on-line and laboratory FTNIR analyzers located in multiple countries are considered, and the ultimate limitations discussed.

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Development of an Optimization Technique of CETOP-D Inlet Flow Factor for Reactor Core Thermal Margin Improvement (원자로심의 열적여유도 증대를 위한CETOP-D의 입구유량인자 최적화 기법 개발)

  • Hong, Sung-Deok;Lim, Jong-Seon;Yoo, Yeon-Jong;Kwon, Jung-Tack;Park, Jong-Ryul
    • Nuclear Engineering and Technology
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    • v.27 no.4
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    • pp.562-570
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    • 1995
  • The recent ABB/CE(Asea Brown Boveri Combustion Engineering) type pressurized oater reactor-s have the on-line monitoring system, i.e., the COLSS(core operating limit supervisory system), to prevent the specified acceptable fuel design limits from being violated during normal operation and anticipated operational occurrences. One of the main functions of COLSS is the on-line monitoring of the DNB(departure from nucleate boiling) overpower margin by calculating the MDNBR(mini-mum DNB ratio) for the measured operating condition at every second. The CETOP-D model, used in the MDNBR calculation of COLSS, is benchmarked conservatively against the TORC mod-el using an inlet flow factor of hot assembly in CETOP-D as an adjustment factor for TORC. In this study, a technique to optimize the CETOP-D inlet flow factor has been developed by elim-inating the excessive conservatism in the ABB/CE's. A correlation is introduced to account for the actual variation of the CETOP-D inlet flow factor within the core operating limits. This technique was applied to the core operating range of the YongGwang Units 3&4 Cycle 1, which results in the increase of 2% in the DNB overpower margin at the normal operating condition, compared with that from the ABB/CE method.

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