• Title/Summary/Keyword: retaining time

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Filtering and Segmentation of radar imagery

  • Kang, Sung-Chul;Kim, Young-seup;Yoon, Hong-Joo;Baek, Seung-Gyun
    • Proceedings of the KSRS Conference
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    • 1999.11a
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    • pp.421-424
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    • 1999
  • The purpose of this study is to demonstrate a variety of methods for reducing the speckle noise content of SAR images, whilst at the same time retaining the fined details and average radiometric properties of the original data. In order to increase the accuracy of classification, Two categories of filters are used (speckleblind(simple), Speckle aware(intelligent)) and Segmentation of highly speckled radar imagery is achieved by the use of the Gaussian Markov Random Field model(GMRF). The problems in applying filtering techniques to different object types are discussed and the GMRF procedure and efficiency of the segmentation also discussed.

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Production and Quality Control of Long Distance Delivered High Strength Concrete (장거리 운반 고강도 콘크리트 제조 및 품질관리)

  • 박연동;정재동;박기청;노재호;조일호;방희상;국중욱
    • Proceedings of the Korea Concrete Institute Conference
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    • 1995.04a
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    • pp.8-13
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    • 1995
  • High strength ready-miced concrete with delivering time of about 90 minutes is successfully produced at ready-mixed concrete plant and placed columns and retaining walls of a tall building without any problems. The design strength of the concrete is 450 kgf/$\textrm{cm}^2$ and the required average compressive strength is 540 kgf/$\textrm{cm}^2$ according to ACI 363R-84 report with assumed coefficient of variation of 12% For the producing of good quality concrete, many laboratary and field tests are carried out. As the results of this study, the slump loss of high strength concrete is largely influenced by kinds of superplasticizer. The measured pump pressure of high strength concrete with slump of 22cm is higher than that of normal strength concrete with slump of 18cm by about 20~30% The measured average 28-day compressive strength of the concrete is 551 kgf/$\textrm{cm}^2$ and the coefficient of variation is 2.3%

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A Neural Network Modulars for Real-time Detection of Bad Materials (불량소자의 검지를 위한 실시간 전송 뉴로 모률라)

  • Kim, Jong-Man;Kim, Won-Sop
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.04c
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    • pp.54-57
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    • 2008
  • A new modular Lateral Information Propagation Networks can be implemented in a IC chip with the circuit VLSI technology for detection of bad materials. The proposed modular architecture is propagated the neural network through inter module connections. For such inter module connections, the host(computer or logic) mediates the exchange of information among modules. Also border nodes in each module have capacitors for temporarily retaining the information from outer modules. For detecting of Faulty Insulator, $4\;{\times}\;4$ neural network modules has been designed and simulation of interpolation with the designed networks has been done.

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An Experimental Study on the Characteristics and Lateral Pressure of Super-Workable Concrete (초유동 콘트리트의 재료적 특성과 거푸집 측압에 관한 실험적 연구)

  • 이준구
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.1
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    • pp.83-91
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    • 2000
  • The purpose of this study is to estimate quantitatively lateral pressure of super-workable fresh concrete applied to form-work of prototype structures, such as tall wall, retaining wall and beam. As a result of this experiment, a function applicable to design a form work system and to predict lateral pressure curve is formulated . Super-workable concrete may be used for the structures reinforced with dense re-bar like box culvert to place concrete at a time, and this study for lateral pressure of super-workable concrete may be useful for form design.

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Behavior of Geosynthetic Reinforced Modular Block Walls under Sustained Loading (지속하중 재하시 보강토 옹벽의 거동특성 - 축소모형실험)

  • Yoo, Chung-Sik;Kim, Sun-Bin;Byun, Jo-Seph;Kim, Young-Hoon;Han, Dae-Hui
    • Proceedings of the Korean Geotechical Society Conference
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    • 2006.03a
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    • pp.121-130
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    • 2006
  • Despite a number of advantages of reinforced earth walls over conventional concrete retaining walls, there exit concerns over long-term residual deformation when used as part of permanent structures. In view of these concerns, time-dependant deformation characteristics of geosynthetic reinforced modular block walls under sustained loads were investigated using reduced-scale model tests. The results indicated that a sustained load can yield appreciable magnitude of residual deformation, and that the magnitude of residual deformation depends on the loading characteristic as well as reinforcement stiffness.

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Case Study of Ground and Supporting System Failure in Soft Ground Deep Excavation (연약지반 깊은 굴착에서 지보재 및 지반 파괴 사례 연구)

  • Kim, Sung-Wook;Han, Byung-Won
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.537-544
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    • 2005
  • We find out many soft ground deep excavation cases where results of careless overexcavation accelerate the advance of loosening zone of adjacent ground, bucklings of struts and bottom heaves happen due to delayed supporting time. This article introduces a soft ground deep excavation case where steel pipe sheet piles were used with struts as an earth retaining system. There were 2 times of buckling in the supporting system and heaving of bottom ground due to overexcavation and insufficient penetration depth of the steel pipe sheet piles. The effort of this article aims to improve and develop the technique of design and construction in the coming projects having similar ground condition and supporting method.

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Surface Strengthening of 3Y-TZP Ceramics by Boehmite Sol Infiltration (Boehmite Sol 함침에 의한 3Y-TZP 소결체의 표면 강화)

  • Choi, Ki-Sik;Kim, Young-Jung;Kim, Hwan
    • Journal of the Korean Ceramic Society
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    • v.31 no.6
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    • pp.671-677
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    • 1994
  • To improve the low resistance of ceramics to tensile stress, many techniques, for introducing and retaining surface compressive stress have been suggested. In present work, in order to introduce the compressive stress on the surface of TZP ceramics TZP-Al2O3 composites were made with infiltration technique. Highly porous 3Y-TZP pre-sintered specimens were submerged in AlOOH(boehmite) sol and the sol penetrated into them through open pore channels with moderate depth after that specimens were sintered. It was known that controlling the number of infiltration time can vary the amount of Al2O3 phase and the fraction of alumina at surface reached up to 18%. The depth of composite surface layer were 100~200 ${\mu}{\textrm}{m}$, and these were acceptable in surface strengthening which were proved by Vickers hardness indentation method.

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Automatic multipoint measuring system using IBM-PC (IBM-PC를 이용한 다점 계측 자동화 시스템)

  • 정상용;양원영
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.541-546
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    • 1989
  • In case there are many points to be measured in the field, conventional measuring system requires a lot of manpower and is liable to miss applying the timely countermeasure because processing and analyzing the data obtained also takes much time. Therefore the purpose of this paper is focused on removing the above defects by introducing automatic multi-point measuring system by use of IBM-PC or the compatibles easily at hand nowadays. Principal components of the system is composed of control box, A/D converter. 32 channel 4 wire switch boxes and strain amplifier. An application software was developed for multi point measurement system in order to efficiently evaluate the stability of the structures such as retaining walls.

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A technique for the reduction of pulse pile-up effect in pulse-shape discrimination of organic scintillation detectors

  • Nakhostin, M.
    • Nuclear Engineering and Technology
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    • v.52 no.2
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    • pp.360-365
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    • 2020
  • A technique for the reduction of pulse pile-up effect in digital pulse-shape discrimination (PSD) of neutrons and gamma-rays with organic scintillation detectors is presented. The technique is based on an electronic reduction of the effective decay-time constant of scintillation pulses while retaining the PSD information of the pulses. The experimental results obtained with a NE213 liquid scintillation detector in a mixed radiation field of neutrons and gamma-rays are presented, demonstrating a figure of merit (FOM) of 1.20 ± 0.05 with an energy threshold of 350 keVee (electron equivalent energy) when the effective length of the pulses is reduced to 50 ns.

Organizational Capabilities for Effective Knowledge Creation: An In-depth Case Analysis of Quinolone Antibacterial Drug Discovery Process (효과적 지식창출을 위한 조직능력 요건: 퀴놀론계 항생제 개발 사례를 중심으로)

  • Lee, Chun-Keun;Kim, Linsu
    • Knowledge Management Research
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    • v.2 no.1
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    • pp.109-132
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    • 2001
  • The purpose of this article is to develop a dynamic model of organizational capabilities and knowledge creation, and at the same time identify the organizational capability factors for effective knowledge creation, by empirically analyzing the history of new Quinolone antibacterial drug compound (LB20304a) discovery process at LG, as a case in point. Major findings of this study are as follows. First, in a science-based area such as drug development, the core of successful knowledge creation lies in creative combination of different bodies of scientific explicit knowledge. Second, the greater the difficulty of learning external knowledge, the more tacit knowledge is needed for the recipient firm to effectively exploit that knowledge. Third, in science-based sector such as pharmaceutical industry, the key for successful knowledge creation lies in the capability of recruiting and retaining star scientists. Finally, for effective knowledge creation, a firm must keep its balance among three dimensions of organizational capabilities: local, process, architectural capabilities.

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