• Title/Summary/Keyword: Data Stability

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The Influence of Foreign Aid on Public Sector Efficiency: A Panel Data Analysis

  • Birendra Narayan SHAH
    • The Journal of Economics, Marketing and Management
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    • v.11 no.3
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    • pp.25-35
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    • 2023
  • Purpose: This paper examines whether foreign aid influences public sector efficiency in policy areas of administration, education, and stability. Research design, data and methodology: The study uses panel data of 77 aid recipient developing countries over the period 2000-2020 and employs various panel data techniques to estimate. Results: We found that a percentage change in foreign aid increases administrative efficiency by 0.02 to 0.04 on average ceteris paribus in the short run. On the other hand, a percentage increase in foreign aid decreases education efficiency by 0.005 to 0.006 on average. While the impact of foreign aid on the policy area of stability is insignificant. Conclusions: The empirical results of this study have important implications for both donors and aid recipient countries. It suggests that to get positive influence from foreign aid, in the area of education and stability, the recipient countries need to increase accessibility of secondary schools with quality education especially; technical and vocational. Also, the donor should provide a minimum threshold amount of foreign aid to developing countries for reforming the institutions' capacity building.

Motion Sensor Fault Detection and Failsafe Logic for Vehic1e Stability Control Systems (VSCs)

  • Yi, Kyongsu;Min, Kyongchan
    • Journal of Mechanical Science and Technology
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    • v.18 no.11
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    • pp.1961-1968
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    • 2004
  • The design of a reliable and failsafe control system requires that sensor failures be detected and identified within acceptable time limit so that system malfunction can be prevented. This paper presents a model-based approach to sensor fault detection with applications to vehicle stability control systems. The effectiveness of the proposed method is illustrated through test data-based evaluation. Vehicle test data-based evaluation results show that the proposed fault management scheme can be used for the design of a failsafe VSCs.

A Study on the Financial Stabilityof households (가계의 경제적 안정에 관한 연구)

  • 황덕순
    • Journal of Families and Better Life
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    • v.11 no.2
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    • pp.69-82
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    • 1993
  • Financial stability of households is the basic and most important factor of the quality of life. It affects emotional psychological mental and social aspects of family personal develop-ment and family healths etc. This study investigated and analyzed the data on financial stability of households. The data collected through the self-administered questionnaire from 466 house-holds in Kwangju area were analyzed. As statistical methods Frequency Percentile. Anova Duncan-test and Regression analysis were used. The results obtained are as follow: Education job status housing tenure type numbers of income source assets income and income flexibility have positive effects on financial stability. Especially numbers of income sources has most important effect. Significant correlation coefficients between financial stability and economic pressures mental healths financial satisfaction life satisfaction and coping behaviors were revealed respectively To improve the quality of life financial stability of household is severely considered. To be financially stable providing various income sources is more desirable than having regular and fixed income.

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Code Development for Online Assessment of Combustion Stability Margin by Utilizing Damping Ratios of Dynamic Pressure Data (동압 데이터의 감쇠계수를 활용한 연소 안정마진 실시간 평가 코드 개발)

  • Song, Won Joon;Ahn, Kwangho;Park, Seik;Kim, Sungchul;Cha, Dong Jin
    • 한국연소학회:학술대회논문집
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    • 2013.06a
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    • pp.117-119
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    • 2013
  • Combustion stability margin of a model gas turbine has been assessed by utilizing damping ratios of measured dynamic pressure data. It is known that acoustic oscillations in combustion chambers can be described as a superposition of nonlinearly interacting oscillators. Based on this theoretical background, CSMA (Combustion Stability Margin Assessment) code has been developed. The code has been employed into a model gas turbine combustion experiment, focused on the combustion instability, to show its capability to determine the damping ratio of measured dynamic pressure and further to assess combustion stability margin of the experiment, and turned out that the code works well.

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Calculation of Combustion Stability Limits Using Linear Stability Analysis in Liquid Rocket Engines (액체 로켓엔진에서 선형 연소 불안정 해석을 이용한 연소 안정한계 곡선 계산)

  • Sohn, Chae-Hoon;Moon, Yoon-Wan;Huh, Hwan-Il
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.32 no.10
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    • pp.93-101
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    • 2004
  • A method to calculate stability limits is investigated to predict the characteristics of high-frequency combustion instability in liquid-propellant rocket engine. It is based on the theory of linear stability analysis proposed in previous works and useful to predict combustion stability at the beginning stage of engine development. The system of equations governing reactive flow in combustor has the simplified and linearized forms. The overall equation expressing stability limits is adopted. The procedures to evaluate quantitatively each term included in the equation are proposed. The thermo-chemical properties and flow variables required in the evaluation can be obtained from calculation of thermodynamic equilibrium, CFD results, and experimental test data. Based on the existent data, stability limits are calculated with actual rocket engine (KSR-III rocket engine). The present calculations show the reasonable stability limits in a quantitative manner and the stability characteristics of the engine are discussed. The prediction from linear stability analysis could be serve as the first approximation to the true prediction.

Assessment of slope stability using multiple regression analysis

  • Marrapu, Balendra M.;Jakka, Ravi S.
    • Geomechanics and Engineering
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    • v.13 no.2
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    • pp.237-254
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    • 2017
  • Estimation of slope stability is a very important task in geotechnical engineering. However, its estimation using conventional and soft computing methods has several drawbacks. Use of conventional limit equilibrium methods for the evaluation of slope stability is very tedious and time consuming, while the use of soft computing approaches like Artificial Neural Networks and Fuzzy Logic are black box approaches. Multiple Regression (MR) analysis provides an alternative to conventional and soft computing methods, for the evaluation of slope stability. MR models provide a simplified equation, which can be used to calculate critical factor of safety of slopes without adopting any iterative procedure, thereby reducing the time and complexity involved in the evaluation of slope stability. In the present study, a multiple regression model has been developed and tested its accuracy in the estimation of slope stability using real field data. Here, two separate multiple regression models have been developed for dry and wet slopes. Further, the accuracy of these developed models have been compared and validated with respect to conventional limit equilibrium methods in terms of Mean Square Error (MSE) & Coefficient of determination ($R^2$). As the developed MR models here are not based on any region specific data and covers wide range of parametric variations, they can be directly applied to any real slopes.

Takagi-Sugeno Fuzzy Sampled-data Filter for Nonlinear System (비선형 시스템을 위한 Takagi-Sugeno 퍼지 샘플치필터)

  • Kim, Ho Jun;Park, Jin Bae;Joo, Young Hoon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.25 no.4
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    • pp.349-354
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    • 2015
  • This paper presents the stability conditions of the Takagi-Sugeno (T-S) fuzzy sampled-data filter. The error system between the T-S fuzzy system and fuzzy filter is presented. In the sense of the Lyapunov stability analysis, the stability conditions are given, which can be represented in terms of linear matrix inequalities (LMIs). The proposed stability conditions utilize the different approach from the conventional methods, and have better performance than that of the conventional ones. The simulation example is given to show the effectiveness of the proposed method.

THE STRONG STABILITY OF ALGORITHMS FOR SOLVING THE SYMMETRIC EIGENPROBLEM

  • Smoktunowicz, Alicja
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.7 no.1
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    • pp.25-31
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    • 2003
  • The concepts of stability of algorithms for solving the symmetric and generalized symmetric-definite eigenproblems are discussed. An algorithm for solving the symmetric eigenproblem $Ax={\lambda}x$ is stable if the computed solution z is the exact solution of some slightly perturbed system $(A+E)z={\lambda}z$. We use both normwise approach and componentwise way of measuring the size of the perturbations in data. If E preserves symmetry we say that an algorithm is strongly stable (in a normwise or componentwise sense, respectively). The relations between the stability and strong stability are investigated for some classes of matrices.

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The Characteristics of Mode Choice Model by Stated Preference Data (선호의식데이타에 의한 교통수단선택 모델의 특성)

  • 이진우
    • Journal of Korean Society of Transportation
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    • v.13 no.4
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    • pp.31-45
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    • 1995
  • In recent year, especially in the mode choice analysis, it has been perceived that the importance of individual performance data using stated preference(SP) experiments as well as revealed preference data . Since SP experiments present respondent with various hypothetical alternatives, which are produced by a combination of a number of different attribute levels, and ask them to indicate a preference, it is possible to analyze travel behavior under a situation of potential environment change such as proposed alternative mode of transportation. The basic problems, however, remains that SP are not consistent with the actual travel behaviors and the research reports for stability of mode choice model using SP data has not been sufficient. Under this background, this study is to examine the characteristics of mode choice model using the SP data by the following items. $\circled1$ Analysis of factors affecting the mode choice behavior by the variance analysis of orthogonal-arrays-table $\circled2$ The reliability of SP data by transfer intention data $\circled3$ The stability of SP responses obtained from repetitive question by the comparison of model coefficient specified by each repetitive data. $\circled4$ The stability of ranking data in mode choice model For the analysis, we assumed subway operations in the Gwang-Ju , and set up a choice-set of hypothetical options based on Experimental Design Method.

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