• 한국지반공학회논문집
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• 제38권12호
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• pp.103-112
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• 2022

본 연구에서는 시간-침하량 계측 데이터를 기반으로 한 기존 침하 예측 이론식을 확인하였다. 기존 계측 기반 침하 예측 이론식 중 쌍곡선법 및 Asaoka법이 정확도가 높게 나타났으며, 이외 방법은 정확도가 낮은 것으로 확인되었다. 이러한 분석 결과를 토대로 기존 침하 예측 방법의 한계점을 도출하였으며, 이러한 한계점을 보완할 수 있는 개선방안으로써 가중 비선형 회귀분석을 통한 침하 예측 방법을 제시하였다.

• Earthquakes and Structures
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• 제11권5호
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• pp.779-807
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• 2016

Ground Motion Prediction Equations (GMPEs) are essential tools in seismic hazard analysis. With the introduction of probabilistic approaches for the estimation of seismic response of structures, also known as, performance based earthquake engineering framework; new tasks are defined for response spectrum such as the reference criterion for effective structure-specific selection of ground motions for nonlinear time history analysis. One of the recent efforts to introduce a high quality databank of ground motions besides the corresponding selection scheme based on the broadband spectral consistency is the development of SIMBAD (Selected Input Motions for displacement-Based Assessment and Design), which is designed to improve the reliability of spectral values at all natural periods by removing noise with modern proposed approaches. In this paper, a new global GMPE is proposed by using selected ground motions from SIMBAD to improve the reliability of computed spectral shape indicators. To determine regression coefficients, 204 pairs of horizontal components from 35 earthquakes with magnitude ranging from Mw 5 to Mw 7.1 and epicentral distances lower than 40 km selected from SIMBAD are used. The proposed equation is compared with similar models both qualitatively and quantitatively. After the verification of model by several goodness-of-fit measures, the epsilon values as the spectral shape indicator are computed and the validity of available prediction equations for correlation of the pairs of epsilon values is examined. General consistency between predictions by new model and others, especially, in short periods is confirmed, while, at longer periods, there are meaningful differences between normalized residuals and correlation coefficients between pairs of them estimated by new model and those are computed by other empirical equations. A simple collapse assessment example indicate possible improvement in the correlation between collapse capacity and spectral shape indicators (${\varepsilon}$) up to 20% by selection of a more applicable GMPE for calculation of ${\varepsilon}$.

• Asian-Australasian Journal of Animal Sciences
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• 제18권2호
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• pp.179-184
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• 2005

First lactation records (174) of Jersey${\times}$Sahiwal and Holstein Friesian${\times}$Sahiwal half breds under 9 sires maintained at Chandra Shekher Azad University of Agriculture and Technology, Kanpur, Uttar Pradesh, India from 1975-1983, were used to estimate the genetic parameters and to predict herd life milk yield and average milk yield per day of herd life from first lactation traits. The traits included were: age at first calving, first service period, first lactation period, first calving interval, first lactation milk yield, milk yield per day of first calving interval, herd life milk yield, herd life and average milk yield per day of herd life. Most of the production and reproduction traits were found to have positive and significant correlations between them on genetic as well as phenotypic scales. Total twelve regression equations were fitted. The prediction equation of herd life milk yield in both the genetic groups showed linear relationship with AFC, FSP, FLP, FLMY and MY/DCI and was apparent and significant. Similarly, polynomials for milk yield per day of herd life for J${\times}$S and HF${\times}$S half breds also showed linear trend, which was found highly significant. The highest and lowest $R^2$ values were found for FCI and AFC, respectively.

• 한국항공우주학회지
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• 제31권8호
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• pp.19-26
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• 2003

비정상 Euler 방정식 틀에서 동안정 미계수의 정상 예측 방법을 제안하였다. 새로운 접근방법은 비정상 지배방정식을 수정하지 않고 정상 예측방법을 적용하도록 해 준다. 제안된 방법을 통해 lunar 코닝운동 및 나선운동을 사용하여 피치감쇠 계수 합과 개별 값을 계산하였다. ANSR 형상과 Basic Finner 형상에 대한 계산결과는 PNS 계산결과, 실험치, 그리고 비정상적 예측방법을 사용한 결과와 잘 일치하고, 직교좌표계에서 정상적 예측 방법이 피치감쇠 계수의 예측에 성공적으로 적용될 수 있음을 보여준다.

• Geomechanics and Engineering
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• 제22권1호
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• pp.25-33
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• 2020

In metropolitan areas, the quantity and density of the underground structure increase rapidly in recent years. Even though most damage incidents of the underground structure were minor, there were still few incidents causing a great loss in lives and economy. Therefore, the safety evaluation of the underground structure becomes an important issue in the disaster prevention plan. Liquefaction induced uplift is one important factor damaging the underground structure. In order to perform a preliminary evaluation on the safety of the underground structure, simplified prediction equations were introduced to provide a first order estimation of the liquefaction induced uplift. From previous studies, the input motion is a major factor affecting the magnitude of the uplift. However, effects of the input motion were not studied and included in these equations in an appropriate and rational manner. In this article, a numerical simulation approach (FLAC program with UBCSAND model) is adopted to study effects of the input motion on the uplift. Numerical results show that the uplift and the Arias Intensity (Ia) are closely related. A simple modification procedure to include the input motion effects in the Sasaki and Tamura prediction equation is proposed in this article for engineering practices.

• Asian-Australasian Journal of Animal Sciences
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• 제5권1호
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• pp.7-11
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• 1992

Body water compartments in vivo were determined in Holstein cattle with age ranging from 5 to 521 days to obtain an equation to estimate volumes of body water. Live weight ranged from 47 to 480 kg. Compartments were determined as antipyrine space for total body water (TBW), thiocyanate space for extracellular water (ECW) and Evans blue dye space for plasma water (PW). Body water compartments expressed as a percentage of live weight decreased as age in days increased and significantly correlated with age in days. Regression analyses revealed that prediction equations had low accuracy. Regression equations of body water compartments on live weight (WT, kg) were useful for the prediction of body fluid with a high accuracy. Live weight significantly regressed on age in days (Day), which was inferred to be utilized for estimation of standardized live weight in case animals were emaciated by certain causes such as severe diarrhea or dehydration. In conclusion, following equations were presented to estimate body water compartments of cattle in vivo : TBW in liters = $0.556({\pm}0.007)WT+10$, r = 0.993, $SE{\pm}0.7$ ECW in liters = $0.321({\pm}0.008)WT+10$, r = 0.978, $SE{\pm}0.8$ PW in liters = $0.0502({\pm}0.0012)WT+1.6$, r = 0.0983, $SE{\pm}0.1$ WT (kg) = $0.772({\pm}0.018)Day+24$, r = 0.982, $SE{\pm}2.3$.

• 한국해양공학회지
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• 제26권2호
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• pp.14-19
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• 2012

There are insufficient data to consider the effect zone for the marine life of coastal fisheries, because no standard has been defined for the sound level of marine life. In this study, equations for distance attenuation were used to determine the effect zone for oceanic noises. A reference noise level was divided into 4 parts to consider the characteristics of the fishes, and the effect zone of each reference noise level was determined. To increase the reliability of the effect scope, approximately 100 repetitions of blasting work split into several parts by the boring depth, the sound level of the source caused by an increase in weight, and the effect zone were calculated using the prediction equation. According to the prediction, the maximum distance of the effect zone was 4.92 km.

• Geomechanics and Engineering
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• 제37권4호
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• pp.371-382
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• 2024

Measurement or prediction of compression index (C_c) of soils is essential for assessment of total and differential settlement of structures. It is a well-known fact that this parameter is controlled by several index identifiers of soil including initial void ratio, Atterberg limits, overconsolidation ratio, specific gravity, etc. Many studies in the past proposed relationships for prediction of C_c based on different index properties. Therefore, this study aims to present a comparison of previously proposed equations for estimation of C_c. Data from literature was compiled, and a total of 90 and 623 test results on remolded and undisturbed specimens were used to question the validity of previously proposed equations. Nevertheless, the modeling ability of 7 and 12 equations for estimation of C_c of remolded and undisturbed soils were questioned by use of compiled data. Moreover, new empirical relationships based on initial void ratio and toughness limit for prediction of C_c was proposed by use of nonlinear multivariable regression and evolutionary based regression analyses. The results are promising-the performances of models established are quite acceptable, which are verified by statistical analyses.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.615-618
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• 2005

This study concerns the equation of high strength concrete by schmidt hammer test. There are not only few prediction strength equations of concrete by schmidt hammer test, but also many problems to apply them because of time, cost, easiness, structural damage, reliability and so on. For this study, there performed a series of schmidt hammer test with in existing 1,095days' concrete structures and proposed equations as follows ; Linear: ${\Large f}_{ck}=-45.35+2.44R(r^2=72.7\%)$ Quadratic: ${\Large f}_{ck}=-502.08+24.0R-0.25R^2(r^2=82.4\%)$ here, $f_{ck}$ : Estimated compressive strength of concrete by MPa, R : Rebound index of concrete

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.337-338
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• 2010

이 논문에서는 고강도 콘크리트의 크리프 특성에 관한 연구로서 실험을 통해 얻어진 결과를 여러 크리프 예측식과 비교하여 기술하였다. 따라서 고강도 콘크리트의 크리프 특성을 규명하기 위해 1종 시멘트로 제작된 대상 콘크리트에 대해 ACI-209 및 CEB/FIP-90의 크리프 예측식에 의한 결과와 비교 검토하여 크리프 예측식의 적용 가능성을 검토하였다.