• Title/Summary/Keyword: Impact coefficients

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The International Influence of China's Equipment Manufacturing Industry: Evidence from the WIOT

  • Ying, Wang;Lan, Li
    • Journal of Distribution Science
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    • v.14 no.10
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    • pp.21-27
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    • 2016
  • Purpose - This study analyzes economic relations and mutual influence in the global equipment manufacturing industry (EMI) and China's influence. Research design, data, and methodology - Data were collected from the World Input-Output Database (WIOT), looking at 16 countries. The sample time period was 2002-2011. Influence and motivation coefficients were calculated. Results - 1) China's EMI showed a very strong influence coefficient, even surpassing world industrial powers like Japan, the USA, Germany, and Korea. 2) As for influence on added-value, China's EMI motivation coefficient was ranked third in 2011, which meant it had a negligible effect on added-value. 3) From 2002 to 2011, both the influence and motivation coefficients of China's EMI rose. Conclusions - China's EMI has strong influence and motivation coefficients. It has a significant impact on the world EMI, especially on the total output of the global EMI. Additionally, during 2002 to 2011, the ranking of China's EMI motivation coefficient improved year over year, and its economic efficiency obviously improved. By 2011, China's EMI's international influence was second only to the US and Japan.

Estimation of runoff coefficient through impervious covers analysis using long-term outflow simulation (장기유출 모의를 통한 도시유역 불투수율에 따른 유출계수 변화)

  • Kim, Young-Ran;Hwang, Sung-Hwan
    • Journal of Korean Society of Water and Wastewater
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    • v.28 no.6
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    • pp.635-645
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    • 2014
  • The changes of rainfall pattern and impervious covers have increased disaster risks in urbanized areas. Impervious covers such as roads and building roofs have been dramatically increased. So, it is falling the ability safety of flood defense equipments to exist. Runoff coefficient means ratio of runoff by whole rainfall which is able to directly contribute at surface runoff during rainfall event. The application of accurate runoff coefficients is very important in sewer pipelines design. This study has been performed to estimate runoff characteristics change which are applicable to the process of sewer pipelines design or various public facilities design. It has used the SHER model, a long-term runoff model, to analyze the impact of a rising impervious covers on runoff coefficient change. It thus analyzed the long-term runoff to analyze rainfall basins extraction. Consequently, it was found that impervious surfaces could be a important factor for urban flood control. We could suggest the application of accurate runoff coefficients in accordance to the land Impervious covers. The average increase rates of runoff coefficients increased 0.011 for 1% increase of impervious covers. By having the application of the results, we could improve plans for facilities design.

Robust Fuzzy Varying Coefficient Regression Analysis with Crisp Inputs and Gaussian Fuzzy Output

  • Yang, Zhihui;Yin, Yunqiang;Chen, Yizeng
    • Journal of Computing Science and Engineering
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    • v.7 no.4
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    • pp.263-271
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    • 2013
  • This study presents a fuzzy varying coefficient regression model after deleting the outliers to improve the feasibility and effectiveness of the fuzzy regression model. The objective of our methodology is to allow the fuzzy regression coefficients to vary with a covariate, and simultaneously avoid the impact of data contaminated by outliers. In this paper, fuzzy regression coefficients are represented by Gaussian fuzzy numbers. We also formulate suitable goodness of fit to evaluate the performance of the proposed methodology. An example is given to demonstrate the effectiveness of our methodology.

Lens Distortion Correction of images with Gradient Components

  • Park, Junhee;Lee, Byung-Uk
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.7
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    • pp.231-235
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    • 2013
  • Lens distortions have a significant impact on captured or projected image geometry. This paper proposes a lens distortion correction with gradient components for wide-angle lenses. In most cases, distortion coefficients are estimated using a distortion model by point correspondences. Corrected images using only point correspondences can be compensated excessively, therefore, producing bended lines into the opposite direction near the corners. To curtail these phenomena, we propose to adopt the gradient components in addition to positions to obtain the distortion coefficients. We verified the improved accuracy and the straightness of the proposed method through experimentation.

Study on Damping Characteristics of Hydropneumatic Suspension Unit of Tracked Vehicle

  • Cho, Jin-Rae;Lee, Hong-Woo;Yoo, Wan-Suk;Lee, Jin-Kyu
    • Journal of Mechanical Science and Technology
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    • v.18 no.2
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    • pp.262-271
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    • 2004
  • Hydropneumatic suspension unit is an important part of tracked vehicles to absorb external impact load exerted from the non-paved road and the cannon discharge. Its absorption performance is strongly influenced by both damping and spring forces of the unit. In this paper, we numerically analyze the damping characteristics of the in-arm-type hydropneumatic suspension unit (ISU) by considering four distinct dynamic modes of the ISU damper: jounce-loading, jounce-unloading, rebound-loading and rebound-unloading. The flow rate coefficients determining the oil flow rate through the damper orifice are decided with the help of independent experiments. The wheel reaction force, the flow rate at cracking and the damping energy are parametrically investigated with respect to the orifice diameter and the wheel motion frequency.

An anisotropic ultrasonic transducer for Lamb wave applications

  • Zhou, Wensong;Li, Hui;Yuan, Fuh-Gwo
    • Smart Structures and Systems
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    • v.17 no.6
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    • pp.1055-1065
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    • 2016
  • An anisotropic ultrasonic transducer is proposed for Lamb wave applications, such as passive damage or impact localization based on ultrasonic guided wave theory. This transducer is made from a PMNPT single crystal, and has different piezoelectric coefficients $d_{31}$ and $d_{32}$, which are the same for the conventional piezoelectric materials, such as Lead zirconate titanate (PZT). Different piezoelectric coefficients result in directionality of guided wave generated by this transducer, in other words, it is an anisotropic ultrasonic transducer. And thus, it has different sensitivity in comparison with conventional ultrasonic transducer. The anisotropic one can provide more information related to the direction when it is used as sensors. This paper first shows its detailed properties, including analytical formulae and finite elements simulations. Then, its application is described.

A Kullback-Leibler divergence based comparison of approximate Bayesian estimations of ARMA models

  • Amin, Ayman A
    • Communications for Statistical Applications and Methods
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    • v.29 no.4
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    • pp.471-486
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    • 2022
  • Autoregressive moving average (ARMA) models involve nonlinearity in the model coefficients because of unobserved lagged errors, which complicates the likelihood function and makes the posterior density analytically intractable. In order to overcome this problem of posterior analysis, some approximation methods have been proposed in literature. In this paper we first review the main analytic approximations proposed to approximate the posterior density of ARMA models to be analytically tractable, which include Newbold, Zellner-Reynolds, and Broemeling-Shaarawy approximations. We then use the Kullback-Leibler divergence to study the relation between these three analytic approximations and to measure the distance between their derived approximate posteriors for ARMA models. In addition, we evaluate the impact of the approximate posteriors distance in Bayesian estimates of mean and precision of the model coefficients by generating a large number of Monte Carlo simulations from the approximate posteriors. Simulation study results show that the approximate posteriors of Newbold and Zellner-Reynolds are very close to each other, and their estimates have higher precision compared to those of Broemeling-Shaarawy approximation. Same results are obtained from the application to real-world time series datasets.

The Impact of Chronic Illness on Children and their Families (아동의 만성질환이 환아 및 환아 가족의 일상생활에 미치는 영향)

  • Han, Kyung-Ja;Park, Yeun-Hwan
    • Journal of Korean Academic Society of Home Health Care Nursing
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    • v.8 no.2
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    • pp.135-147
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    • 2001
  • The aim of this descriptive study was to identify the impact of chronic illness on children and their families. Mothers of 177 children with chronic disease were recruited from aged one to 17 years hospitalizing the pediatric nursing unit at one university hospital. 28 questions. a self-complete maternal questionnaire developed by researchers based on literatures and 'The Impact of Childhood Illness Scale' (Hoare & Russell, 1995) assess four aspects of the child's and family's lifestyle with two dimensions for each question. the frequency of the problem and its importance of concern that it cause. In the data analysis. Pearson correlation coefficients and analysis of variance were used to test any association and a statistical comparisons. between individual variables and the impact on child's and family's lifestyle. The results were as follows: 1) There were the higher mean scores on the importance dimension than on the frequency dimension on total impact on child's and family's lifestyle. On the importance dimension. mothers had much higher levels of concern about impact on child's development and adjustment among subscales. On the frequency dimension, mothers had much higher levels of concern about impact on the family daily living on subscales. 2) The impact on child's and family's lifestyle related on individual variables were: (1) On the importance dimension. there was statistically significant low in the impact on child's development and adjustment among subscales in older parent group compared with it of younger parent group. (2) On the frequency dimension. there were statistically significant high in the impact on child's development and adjustment among subscales in the children with leukemia or cancer compared with it of the other children who had another chronic illnesses. And there were statistically significant high in the impact on child's development and adjustment among subscales in less than high school educated mothers compared with it of mothers who was educated college level. (3) On the frequency dimension. There were statistically significant high in the impact on family's daily living among subscales and total impact on child's and family's lifestyle in female children. (4) There was positive correlation between impact on parents daily living and frequency of child's hospitalization on the frequency dimension. but there was negative correlation between the two variables on the importance dimension. (5) There was positive correlation between impact of chronic illness and its treatment and duration of child's hospitalization on the frequency dimension. In conclusion. these results were reflected by the high level of concerns about impact on child's development and adjustment although mothers had frequently responded about the impact on the family daily living. We suggest consistent intervening program that help the family empowering to make children live with and adjust to their chronic illnesses from the point of diagnosis and after discharge from the hospital. We also suggest these results can be utilized as a useful data in the practice of home health nursing for children who have chronic illnesses and their families.

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On the Effect of Air-Simulated Side-Jets on the Aerodynamic Characteristics of a Missile by Multi-Fidelity Modeling (다충실도 모형화를 통한 공기로 모사된 측방제트가 유도무기의 공력특성에 미치는 영향 연구)

  • Kang, Shinseong;Kang, Dayoung;Lee, Kyunghoon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.49 no.2
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    • pp.95-106
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    • 2021
  • Side-jets enable the immediate maneuver of a missile compared to control surfaces; however, they may cause adverse effects on aerodynamic coefficients, for they interfere with freestream. To find out the impact of side-jets on aerodynamic coefficients, we simulate side-jets as air gas and utilize multi-fidelity models to evaluate differences between aerodynamic coefficients obtained with and without side-jets. We computed differences in aerodynamic coefficients to investigate side-jet effects for the changes of a Mach number, a bank angle, and an angle of attack. As a result, asymmetrically developed side-jets affect the longitudinal force and moment coefficients, and the lateral force and moment coefficients drastically change in-between -30 and 30 degrees of bank angles. In contrast, side-jets hardly influence the axial force coefficients. As for the axial moment coefficient, we could not determine the side-jet effect due to a lack of aerodynamic coefficient samples in the Mach number. All in all, we confirm that side-jets lead to the change of a missile attitude as they considerably vary the longitudinal and lateral aerodynamic coefficients.

The Analysis of Economic Impact for Information Security Industry using Inter-Industry Analysis (산업연관분석을 이용한 정보보호 산업의 경제 파급효과 분석)

  • Jeong, Eun-Hee
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.13 no.1
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    • pp.72-80
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    • 2020
  • The information security industry is increasing in importance and market size due to the development of the fourth industry such as artificial intelligence, IoT and etc. This paper was analyzed the impact of the increasing information security industry on the domestic economy by using the Input-Output table. It was classified industrial sectors into information security products and information security services industries, and then reclassified the Input-Output table into 35 industries. And it was estimated the production inducement coefficient, the value-added inducement coefficient, employment inducement coefficient, and etc. The production inducement coefficients of the information security product and service industry are each 1.571, 1.802, and the value-added inducement coefficients of them are each 0.632, 0.997, and the employment inducement coefficients of them are each 2.494, 7.361. Only the value-added inducement coefficient of the information security service industry is slightly higher than the total industry, and the remaining inducement coefficients are all lower than the total industry. In addition, the information security product industry has no the forward and backward linkage effect, and the information security service industry has no the backward linkage effect. But it has the forward linkage effect. As a result of analyzing the economic ripple effect of the information security industry, the production inducement amounted to 359.9 trillion won, value-added inducement amounted to 164.8 trillion won, and employment inducement amounted to 803 thousand people.