• Title/Summary/Keyword: Linear Slope Method

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Crack Growth Behavior in the Integrally Stiffened Plates(ll) - Experimental Evaluation of SIF- (일체형 보강판의 균열성장거동(II) - SIF의 실험해석 -)

  • Rhee, Hwan-Woo
    • Journal of the Korean Society for Precision Engineering
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    • v.14 no.6
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    • pp.114-120
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    • 1997
  • To assess the validity of the previously computed finite element analysis results, the photoelastic experiment was carried out to determine stress intensity factors for crack originating from thin section of integrally stiffened plates having discontinuous thickness interface. The stress intensity factors were deter- mined by using linear slope method of photoelastic data. Results are presented as variable thickness geometry factor. $F_{IV}$ , for various crack lengths and thickness ratios. The experimental values of F/ sub IV/are compared with 3-D finite element analysis results. The correlation between experimental values and analysis results is resonably good.

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Slope Stability Analysis Considering Multi Failure Mode (다중파괴모드를 고려한 사면안정해석)

  • Kim, Hyun-Ki;Kim, Soo-Sam
    • Journal of the Korean Society for Railway
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    • v.14 no.1
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    • pp.24-30
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    • 2011
  • Conventional slope stability analysis is focused on calculating minimum factor of safety or maximum probability of failure. To minimize inherent uncertainty of soil properties and analytical model and to reflect various analytical models and its failure shape in slope stability analysis, slope stability analysis method considering simultaneous failure probability for multi failure mode was proposed. Linear programming recently introduced in system reliability analysis was used for calculation of simultaneous failure probability. System reliability analysis for various analytical models could be executed by this method. For application analysis for embankment, the results of this method shows that system stability of embankment calculate quantitatively.

Analysis for the Safety Factor of Slope and Seepage according to Change Cross-Section in the Reservoir Embankments (저수지 제체 단면 형상 변화에 따른 안전율 및 침투유량 분석)

  • Noh, Soo-Kack;Son, Young-Hwan;Bong, Tae-Ho;Park, Jae-Sung;Choi, Woo-Seok
    • Journal of The Korean Society of Agricultural Engineers
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    • v.55 no.6
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    • pp.37-46
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    • 2013
  • Many factors about the stability for the reservoir embankments is determined when the facility is completed. Therefore the initial design of the embankment is important. Many researchers focused the effect of soil parameters although the cross section greatly affects the stability and can be controlled in design step. The objective of this research is to analysis of the effects for the safety factor of slope and seepage according to change cross-section in embankment. As a result, the quantity of seepage decreased as the gradient of downstream slope decreased and was proportional to the height of embankments. There was a linear relationship between the gradient of slope and the safety factor of slope. However the gradient of slope did not affect other side slope. All in a relationship, regressive equations with a high correlation coefficient were calculated and can be applied the simple estimation method of the stability using the cross-section. As results of analyzing the sensitivity, the friction angle and permeability critically effect for the slope stability and the seepage, respectively. The effect of the slope gradient was similar to major soil properties.

Slope Stability Analysis Using the Genetic Algorithm (유전자 알고리즘을 이용한 사면안정 해석)

  • 신방웅;백승철;김홍택;황정순
    • Journal of the Korean Geotechnical Society
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    • v.18 no.6
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    • pp.117-127
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    • 2002
  • A deterministic approach of slope stability, which is generally corresponding to the model of a simple non-linear function for slopes, is problematic in that it does not account the versatile characteristics of ground layers in an effective way. To resolve this problem, this study proposes a new way of analyzing slope stability, so-called “genetic algorithm method, ” so as to reflect some particular conditions pertaining to the grounds under concern. Similarities and differences in slope stability that may exist between homogeneous and multiple ground layers are examined in a competitive manner, Overall, though similarities deemed a little bit salient, the algorithm method turned out to be very applicable to estimating the validity of slope stability. Furthermore, an additional effort to consider long-standing sequential and dynamic changes in both the amount of rainfall and the underground water level is made in order to improve the results.

Comparison of Characteristics of Outflow Hydrograph Using the Linear and Nonlinear Muskingum-Cunge Methods (선형과 비선형 Muskingum-Cunge법에 의한 유출곡선의 특성 비교)

  • Kim, Jin-Su;Kim, Jin-Hong
    • Journal of Korea Water Resources Association
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    • v.32 no.4
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    • pp.417-426
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    • 1999
  • A series of numerical experiments is performed to compare the characteristics of outflow hydrograph using linear and nonlinear Muskingum-Cunge methods for two cases: (a) sinusoidal inflow hydrographs and (b) rainfall inputs. The nonlinear method shows the steepening of the rising limb, coupled with a corresponding flattening of the receding limb. The linear method conserves mass exactly. In contrast, the nonlinear method is subject to a gain and a loss of mass. The loss of mass and the subsidence of peak outflow increases with a mild slope, a small baseflow $q_b$ and a large peak inflow to baseflow ratio $q_p/q_b$. A shock wave and associated numerical instability results in the increase of mass for a steep slope and a large $q_p/q_b$ ratio. While the linear method depends on the reference flow per unit-width, the nonlinear method depends on a baseflow and the $q_p/q_b$ ratio. It is found that, unlike for the sinusoidal inflow, the outflow for the rainfall inputs conserves mass fairly exactly in the nonlinear method.

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Robust inference for linear regression model based on weighted least squares

  • Park, Jin-Pyo
    • Journal of the Korean Data and Information Science Society
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    • v.13 no.2
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    • pp.271-284
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    • 2002
  • In this paper we consider the robust inference for the parameter of linear regression model based on weighted least squares. First we consider the sequential test of multiple outliers. Next we suggest the way to assign a weight to each observation $(x_i,\;y_i)$ and recommend the robust inference for linear model. Finally, to check the performance of confidence interval for the slope using proposed method, we conducted a Monte Carlo simulation and presented some numerical results and examples.

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Analysis of Nigeria Research Reactor-1 Thermal Power Calibration Methods

  • Agbo, Sunday Arome;Ahmed, Yusuf Aminu;Ewa, Ita Okon Bassey;Jibrin, Yahaya
    • Nuclear Engineering and Technology
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    • v.48 no.3
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    • pp.673-683
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    • 2016
  • This paper analyzes the accuracy of the methods used in calibrating the thermal power of Nigeria Research Reactor-1 (NIRR-1), a low-power miniature neutron source reactor located at the Centre for Energy Research and Training, Ahmadu Bello University, Zaria, Nigeria. The calibration was performed at three different power levels: low power (3.6 kW), half power (15 kW), and full power (30 kW). Two methods were used in the calibration, namely, slope and heat balance methods. The thermal power obtained by the heat balance method at low power, half power, and full power was $3.7{\pm}0.2kW$, $15.2{\pm}1.2kW$, and $30.7{\pm}2.5kW$, respectively. The thermal power obtained by the slope method at half power and full power was $15.8{\pm}0.7kW$ and $30.2{\pm}1.5kW$, respectively. It was observed that the slope method is more accurate with deviations of 4% and 5% for calibrations at half and full power, respectively, although the linear fit (slope method) on average temperature-rising rates during the thermal power calibration procedure at low power (3.6 kW) is not fitting. As such, the slope method of power calibration is not suitable at lower power for NIRR-1.

Flow Characteristics and Transverse Bed Slope in Curved Alluvial Channels (만곡 수로의 횡방향 하상경사와 흐름특성)

  • 차영기;이대철
    • Water for future
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    • v.24 no.1
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    • pp.99-107
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    • 1991
  • This study is for simulating to the model which analyzes flow characteristics and transverse bed slopes in a coarse-streambed of the meandering alluvial channels. Using the equations for conservation of mass, momentum, and for lateral stability of the streambed, a linear differential equation of transverse bed slope is derived from the flow characteristics in curved channels. Its solutions are solved by the Sine-generated curve method(SCM) and compared with results of field measurements. Lag distances by the maximum transverse bed slope and velocity profiles will predict risk sections of concave bank under floods.

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A Study on the Estimation of Glottal Spectrum Slope Using the LSP (Line Spectrum Pairs) (LSP를 이용한 성문 스펙트럼 기울기 추정에 관한 연구)

  • Min, So-Yeon;Jang, Kyung-A
    • Speech Sciences
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    • v.12 no.4
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    • pp.43-52
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    • 2005
  • The common form of pre-emphasis filter is $H(z)\;=\;1\;- az^{-1}$, where a typically lies between 0.9 and 1.0 in voiced signal. Also, this value reflects the degree of filter and equals R(1)/R(0) in Auto-correlation method. This paper proposes a new flattening algorithm to compensate the weaked high frequency components that occur by vocal cord characteristic. We used interval information of LSP to estimate formant frequency. After obtaining the value of slope and inverse slope using linear interpolation among formant frequency, flattening process is followed. Experimental results show that the proposed algorithm flattened the weaked high frequency components effectively. That is, we could improve the flattened characteristics by using interval information of LSP as flattening factor at the process that compensates weaked high frequency components.

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Using the Hierarchical Linear Model to Forecast Movie Box-Office Performance: The Effect of Online Word of Mouth

  • Park, Jongmin;Chung, Yeojin;Cho, Yoonho
    • Asia pacific journal of information systems
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    • v.25 no.3
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    • pp.563-578
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    • 2015
  • Forecasting daily box-office performance is critical for planning the distribution of marketing resources, and by extension, maximizing profits. For certain movies, the number of viewers increases rapidly at the beginning of their theatrical run, and the increments slow down later. Other movies are not popular in the beginning, but the audience sizes grow rapidly afterward. Thus, the audience attendance of movies grow in different trajectories, which are influenced by various factors including marketing budget, distributors, directors, actors, and word of mouth. In this paper, we propose a method for predicting the daily performance trajectory of running movies based on the hierarchical linear model. More specifically, we focus on the effect of online word of mouth on the shape of the growth curves. We fitted the mean trajectory of the cumulative audience size as a cubic function of time, and allowed the intercept and slope to vary movie-to-movie. Moreover, we fitted the linear slope with a function of online word of mouth predictors to help determine the shape of the trajectories. Finally, we provide performance predictions for individual movies.