• Title/Summary/Keyword: improved ground

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Seismic Performance Evaluation of SRC Composite Column using Direct Displacement Based Design Method (직접변위기반 설계법에 의한 SRC 합성기둥의 내진성능평가)

  • Jung, In-Kju;Park, Soon-Eung;Kim, Dong-Hyuk
    • Journal of Korean Association for Spatial Structures
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    • v.12 no.3
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    • pp.63-70
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    • 2012
  • In this study, the displacement-based design concept, the performance by the existing reinforced concerte column and steel reinforced concrete composite column for SRC purchased the maximum design ground acceleration improvement compared to the performance design. SRC have several advantages such as strength enhancement and high ductility. H-beam or steel tubes were used for embedded elements of the SRC composite columns. SRC cross-section for the P-M diagram and analysis on the nominal bending monent SRC designed for composite columns for disparity estimation is presented to the displacement-based seismic design. Performance improvement of the performance-based design performance targets for the design seismic displacement and design criteria for the direct displacement-based design methods and to improve the seismic performance due to the displacement coefficient method is proposed to design. SRC compared with the RC column designed to improve the performance and displacement ductility ratio displacement results in the performance design results showed significantly improved performance.

Base Isolation Performance of Friction Pendulum System using Magnetic Force (자력을 이용한 마찰진자 베어링의 면진성능)

  • Hwang, In-Ho;Shin, Ho-Jae;Lee, Jong-Seh
    • Journal of the Earthquake Engineering Society of Korea
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    • v.12 no.4
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    • pp.55-61
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    • 2008
  • One of the most recent base-isolation systems to improve the earthquake resistance of structures is the Friction Pendulum System(FPS). Simple in design but with versatile properties, the FPS has been used in some of the world s largest seismically isolated buildings, bridges and chemical tanks. FPS using PTFE(Polytetrafl-uoroethylene) based material has been developed to provide a simple and effective way for structures to achieve earthquake resistance. PTFE materials are soft, and are apt to become deformed easily after a few working cycles. In this study, magnetic force is used rather than the usual PTFE materials to improve the material shortcomings. A MF-FPS(Magnetic force-Friction Pendulum System) is proposed, and us shown to effectively protect structures against earthquakes. To demonstrate the advantages of this new system, the MF-FPS is compared with FPS as an attempt to prove its performance. A six-degree-of-freedom model is considered as a numerical example. The ground acceleration data of El Centro, Mexico and Gebze earthquakes are used as seismic excitations. The results showed that MF-FPS improved performance compared with FPS.

Evaluating non-coincident Cadastral Parcel Using Google Earth Web (Google Earth Web을 활용한 지목 불부합 필지 평가)

  • Kim, Dae-Ho;Um, Jung-Sup
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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    • 2010.06a
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    • pp.9-18
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    • 2010
  • This study investigated the cadastral non-coincidence between real land using and cadastral book using Google Earth Web for difficult area to access that is more efficient method compared with field survey for saving time and money. An reading error has occurred eight parcels about dry field and paddy field but this method is more powerful in case of a danger area of steep, unregistered cemeteries of cadastral book using Google Earth Web of image interpretation that method takes 1 day, the accuracy is 96% and improved 20% more than field survey takes 5 days by 40 parcels. It's possible to reduce the manpower, time and budget could be minimized. In particular, it is need to land alteration of forests and fields category that finds 47 locations a burial ground of non register cadastre book. Google Earth Web method is enabling easy visual analysis of the future land administration of local governments to improving the reliability of temporal and economic costs can be very useful to reduce.

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A Design of Two Layer Re-entrant Microstrip Directional Coupler Improving Coupling and Isolation (결합도와 격리도를 개선한 이중층 Re-entrant 마이크로스트립 방향성 결합기 설계)

  • 최문호;이진택;천동완;신철재
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.14 no.10
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    • pp.1052-1059
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    • 2003
  • In this paper, we proposed the directional coupler using two layer microstrip substrate which is improved coupling and isolation. Also, we notified a design method. Modified re-entrant mode coupler is the structure added to the aperture on the ground plane in order to improving the coupling value. And, by adding to slits on the floating conductor, this structure has good performance in isolation, VSWR according to S$\sub$11/, and phase difference. As a result, proposed re-entrant mode microstrip directional coupler has about 1.5 dB more higher coupling and 20 dB more higher isolation than conventional coupler. And because this coupler has good performance in phase difference, it can be used multi-section coupler.

A Case of Giant Cell Interstitial Pneumonia without History of Exposure to Hard Metal (경금속에 대한 노출력이 없는 거대세포 간질성 폐렴(Giant Cell Interstitial Pneumonia) 1예)

  • Hong, Ji Hyun;Lee, Jae Myung;Kang, Min Jong;Kim, Dong Gyu;Jung, Ki-Suck;Jang, Kee-Tark;Park, Hye-Rim;Lee, In Jae
    • Tuberculosis and Respiratory Diseases
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    • v.52 no.4
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    • pp.419-424
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    • 2002
  • A 44 year old man was admitted complaining fo exertional dyspnea. The patient denied any occupational history of hard metal exposure. Chest radiography showed an increased interstitial marking at the peripheral portion of both lower lung fields. The spirometric values were within the normal ranges. However, the diffusion capacity of the lungs was lower. In the bronchial lavage fluid, the characteristic multinucleated giant cells were noticed, and the macrophage compartment was 96% and the neutrophils were 4%. High-resolution CT scan revealed ground glass opacities with emphysematous lung changes at the peripheral portion of the whole lung. An open lung biopsy confirmed the presence of numerous multinucleated giant cells (define GIP) with an associated interstitial fibrosis throughout the lung. The radiographic abnormailities and symptoms subsequently improved following treatment with oral corticosteroids.

Bayesian Parameter Estimation for Prognosis of Crack Growth under Variable Amplitude Loading (변동진폭하중 하에서 균열성장예지를 위한 베이지안 모델변수 추정법)

  • Leem, Sang-Hyuck;An, Da-Wn;Choi, Joo-Ho
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.35 no.10
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    • pp.1299-1306
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    • 2011
  • In this study, crack-growth model parameters subjected to variable amplitude loading are estimated in the form of a probability distribution using the method of Bayesian parameter estimation. Huang's model is employed to describe the retardation and acceleration of the crack growth during the loadings. The Markov Chain Monte Carlo (MCMC) method is used to obtain samples of the parameters following the probability distribution. As the conventional MCMC method often fails to converge to the equilibrium distribution because of the increased complexity of the model under variable amplitude loading, an improved MCMC method is introduced to overcome this shortcoming, in which a marginal (PDF) is employed as a proposal density function. The model parameters are estimated on the basis of the data from several test specimens subjected to constant amplitude loading. The prediction is then made under variable amplitude loading for the same specimen, and validated by the ground-truth data using the estimated parameters.

The Design of repeater U-shaped Antenna for ship base station Applications (선박기지국 응용을 위한 중계기용 U형 급전 안테나 설계)

  • Park, Chang-Hyun;Kim, Young-Nam;Kim, Kab-Ki
    • Proceedings of KOSOMES biannual meeting
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    • 2007.11a
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    • pp.211-214
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    • 2007
  • In this paper, we have designed microstrip antenna if 800[MHz] band It will be able to integrate TRS(Trunked Radio System), GSM(Global System for Mobile telecommunication) band including the CDMA(Code Division Multiple Access) band we designed repeater and a base station antenna which is possible at the ship and marine of safety. It is improves a narrow bandwidth problem of microstrip antenna. It had U-shaped feeding structure at a rectangular patch And ground or feeding structure used between dielectric constant(${\varepsilon}_T$ = 2.1), patch or feeding structure used between dielectric constant(${\varepsilon}_T$ =1). So it used a duplex resonance effect Designed frequency bandwith(V5WR 2:1) if the antenna showed good characteristic of $780[MHz]{\sim}1.83[GHz]$ to 2.61[GHz]. Also the E-plan and H-plan all profit 9.4[dBi] above, the 3[dB] beam width showed the characteristic over the E-plan and H-plan $60^{\circ}$ to be improved.

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Estimation of ambient PM10 and PM2.5 concentrations in Seoul, South Korea, using empirical models based on MODIS and Landsat 8 OLI imagery

  • Lee, Peter Sang-Hoon;Park, Jincheol;Seo, Jung-young
    • Korean Journal of Agricultural Science
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    • v.47 no.1
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    • pp.59-66
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    • 2020
  • Particulate matter (PM) is regarded as a major threat to public health and safety in urban areas. Despite a variety of efforts to systemically monitor the distribution of PM, the limited amount of sampling sites may not provide sufficient coverage over the areas where the monitoring stations are not located in close proximity. This study examined the capacity of using remotely sensed data to estimate the PM10 and PM2.5 concentrations in Seoul, South Korea. Multiple linear regression models were developed using the multispectral band data from the Moderate-resolution imaging spectro-radiometer equipped on Terra (MODIS) and Operational Land Imager equipped on Landsat 8 (Landsat 8) and meteorological parameters. Compared to MODIS-derived models (r2 = 0.25 for PM10, r2 = 0.30 for PM2.5), the Landsat 8-derived models showed improved model reliabilities (r2 = 0.17 to 0.57 for PM10, r2 = 0.47 to 0.71 for PM2.5). Landsat 8 model-derived PM concentration and ground-truth PM measurements were cross-validated to each other to examine the capability of the models for estimating the PM concentration. The modeled PM concentrations showed a stronger correlation to PM10 (r = 0.41 to 0.75) than to PM2.5 (r = 0.14 to 0.82). Overall, the results indicate that Landsat 8-derived models were more suitable in estimating the PM concentrations. Despite the day-to-day fluctuation in the model reliability, several models showed strong correspondences of the modeled PM concentrations to the PM measurements.

Life-Cycle Analysis of Nuclear Power Plant with Seismic Isolation System (면진장치 적용을 고려한 원전구조물 생애주기 분석)

  • Kim, Sunyong;Lee, Hong-Pyo;Cho, Myung-Sug
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.26 no.6
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    • pp.415-421
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    • 2013
  • In order to extend the service life of a nuclear power plant(NPP) ensuring the structural safety, effective and efficient management of NPP considering structural deteriorations and various natural hazard risks has been treated as a significant tool(IAEA 1998). The systemic efforts is required to prevent the potential loss of NPPs resulting from the natural hazard including earthquakes, hurricane and flooding since the Fukushima accident. Earthquake risk of building structures can be mitigated through appropriate seismic isolation system installation. It has been known that a seismic isolation system can lead to reduction of the deleterious effect on ground motion induced by earthquakes, and structural safety can be improved. In this paper, the NPP life-cycle management is reviewed. Furthermore, effect of seismic isolation on the NPP life-cycle cost analysis with earthquake, and cost-benefit analysis in terms of life-cycle cost when applying the seismic isolation systems to NPP are introduced.

An Improved Face Detection Method Using a Hybrid of Hausdorff and LBP Distance (Hausdorff와 LBP 거리의 융합을 이용한 개선된 얼굴검출)

  • Park, Seong-Chun;Koo, Ja-Young
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.11
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    • pp.67-73
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    • 2010
  • In this paper, a new face detection method that is more accurate than the conventional methods is proposed. This method utilizes a hybrid of Hausdorff distance based on the geometric similarity between the two sets of points and the LBP distance based on the distribution of local micro texture of an image. The parameters for normalization and the optimal blending factor of the two different metrics were calculated from training sample images. Popularly used face database was used to show that the proposed method is more effective and robust to the variation of the pose, illumination, and back ground than the methods based on the Hausdorff distance or LBP distance. In the particular case, the average error distance between the detected and the true face location was reduced to 47.9% of the result of LBP method, and 22.8% of the result of Hausdorff method.