• 제목/요약/키워드: Moment

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Choice of the Kernel Function in Smoothing Moment Restrictions for Dependent Processes

  • Lee, Jin
    • Communications for Statistical Applications and Methods
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    • 제16권1호
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    • pp.137-141
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    • 2009
  • We study on selecting the kernel weighting function in smoothing moment conditions for dependent processes. For hypothesis testing in Generalized Method of Moments or Generalized Empirical Likelihood context, we find that smoothing moment conditions by Bartlett kernel delivers smallest size distortions based on empirical Edgeworth expansions of the long-run variance estimator.

THE COMPLETE MOMENT CONVERGENCE FOR ARRAY OF ROWWISE ENOD RANDOM VARIABLES

  • Ryu, Dae-Hee
    • 호남수학학술지
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    • 제33권3호
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    • pp.393-405
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    • 2011
  • In this paper we obtain the complete moment convergence for an array of rowwise extended negative orthant dependent random variables. By using the result we can prove the complete moment convergence for some positively orthant dependent sequence satisfying the extended negative orthant dependence.

카마스터의 지각된 핵심역량 수준이 고객만족에 미치는 영향: 고객접점(MOT)품질의 매개효과를 중심으로 (The Influence of the Car Master's Recognized Core Capability level in Achieving Customer Satisfaction: Emphasis on Mediating Effect of Moment of Truth Quality)

  • 안성범;송인암;황희중
    • 유통과학연구
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    • 제11권4호
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    • pp.37-49
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    • 2013
  • Purpose - This research identifies the meaning of the core capability level of Car Master and the reason why its service at the Moment of Truth should be demonstrated through empirical cases. It can be seen that this study differs from existing research because it proposes that the recognized core capability level to achieve customer satisfaction should focus on the mediating effect of Moment of Truth quality. This paper examines the effect of Car Master's recognized core capability level on customer satisfaction by using the variables mentioned above. Moreover, this study uses regression analysis to verify that the mediating effect of Moment of Truth quality on Car Master's capability level achieves customer satisfaction. Research design, data, and methodology - First, we present evidence that could apply to Car Master's recognized core capability level by detailing the relationship between customer satisfaction and a structuring factor for Car Master's core capability level. Our proposed research model observes the relationship between the structuring factor of core capability and customer satisfaction. Second, we had an opportunity to define how the core capability and Moment of Truth quality affect customer satisfaction by performing empirical analysis on the partial mediating effect of Moment of Truth quality at a recognized core capability level and Moment of Truth quality affecting customer satisfaction. Results - First, the results indicate that Car Master's recognized core capability level (product professionalism, marketing skill, and reliability) positively affects customer satisfaction. Second, the results show that an ability to listen and a sense of dedication positively affect customer satisfaction, and are among the Moment of Truth quality factors; but performance capability, which is one of the Moment of Truth quality factors, does not positively affect customer satisfaction. These results clearly differ from prior studies focused on Moment of Truth quality and consumer satisfaction. Third, the results show that Moment of Truth quality has a partial mediating effect in terms of the impact of Car Master's recognized core capability level in achieving consumer satisfaction. Conclusions - This research indicates that the company will be able to expand if they investigate and show an interest in more training and education for Car Master. The study verified that outstanding Car Masters show differentiated performance on customer satisfaction at the Moment of Truth in various instances. Thus, we believe that this is the time for a discussion on systematic and empirically recognized core capability levels and the Moment of Truth quality. The study on Car Master's recognized core capability level offers suitable solutions for Car Masters to respond to customers at the Moment of Truth. Further, this study emphasizes the importance of service as a critical factor having a direct relationship with the company's success and failure and contributing to building trust with the customer. Thus, an investment in continuous education and training for Car Master will help the growth of the business.

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Use of UHPC slab for continuous composite steel-concrete girders

  • Sharif, Alfarabi M.;Assi, Nizar A.;Al-Osta, Mohammed A.
    • Steel and Composite Structures
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    • 제34권3호
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    • pp.321-332
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    • 2020
  • The loss of composite action at the hogging moment zone for a continuous composite girder reduces the girder stiffness and strength. This paper presents an experimental investigation of the use of an ultra-high performance concrete (UHPC) slab at the hogging moment zone and a normal concrete (NC) slab at the sagging moment zone. The testing was conducted to verify the level of loading at which composite action is maintained at the hogging moment zone. Four two-span continuous composite girders were tested. The thickness of the UHPC varied between a half and a full depth of slab. The degree of shear connection at the hogging moment zone varied between full and partial. The experimental results confirmed the effectiveness of the UHPC slab to enhance the girder stiffness and maintain the composite action at the hogging moment zone at a load level much higher than the upper service load limit. To a lesser degree enhanced performance was also noted for the smaller thickness of the UHPC slab and partial shear connection at the hogging moment zone. Plastic analysis was conducted to evaluate the ultimate capacity of the girder which yielded a conservative estimation. Finite element (FE) modeling evaluated the girder performance numerically and yielded satisfactory results. The results indicated that composite action at the hogging moment zone is maintained for the degree of shear connection taken as 50% of the full composite action and use of UHPC as half depth of slab thickness.

Seismic Performance of High-Rise Intermediate Steel Moment Frames according to Rotation Capacities of Moment Connections

  • Han, Sang Whan;Moon, Ki-Hoon;Ha, Sung Jin
    • 국제초고층학회논문집
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    • 제4권1호
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    • pp.45-55
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    • 2015
  • The rotation capacity of the moment connections could significantly influence on the seismic performance of steel moment resisting frames. Current seismic provisions require that beam-to-column connections in Intermediate Moment Frames (IMF) should have a drift capacity as large as 0.02 radian. The objective of this study was to evaluate the effect of the rotation capacity of moment connections on the seismic performance of high-rise IMFs. For this purpose, thirty- and forty-story high-rise IMFs were designed according to the current seismic design provisions. The seismic performance of designed model frames was evaluated according to FEMA P695. This study showed that the forty-story IMF satisfied the seismic performance objective specified in FEMA P695 when the rotation capacity of the connections was larger than 0.02. However, thirty-story IMFs satisfied the performance objective when the connection rotation capacity is larger than 0.03.

Force transfer mechanism in positive moment continuity details for prestressed concrete girder bridges

  • Hossain, Tanvir;Okeil, Ayman M.
    • Computers and Concrete
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    • 제14권2호
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    • pp.109-125
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    • 2014
  • The force transfer mechanism in positive moment continuity details for prestressed concrete girder bridges is investigated in this paper using a three-dimensional detailed finite element model. Positive moment reinforcement in the form of hairpin bars as recommended by the National Cooperative Highway Research Program Report No 519 is incorporated in the model. The cold construction joint that develops at the interface between girder ends and continuity diaphragms is also simulated via contact elements. The model is then subjected to the positive moment and corresponding shear forces that would develop over the service life of the bridge. The stress distribution in the continuity diaphragm and the axial force distribution in the hairpin bars are presented. It was found that due to the asymmetric configuration of the hairpin bars, asymmetric stress distribution develops at the continuity diaphragm, which can be exacerbated by other asymmetric factors such as skewed bridge configurations. It was also observed that when the joint is subjected to a positive moment, the tensile force is transferred from the girder end to the continuity diaphragm only through the hairpin bars due to the lack of contact between the both members at the construction joint. As a result, the stress distribution at girder ends was found to be concentrated around the hairpin bars influence area, rather than be resisted by the entire girder composite section. Finally, the results are used to develop an approach for estimating the cracking moment capacity at girder ends based on a proposed effective moment of inertia.

감아굽힘 장치를 이용한 스프링백 비의 측정에 대한 역학적 검토 (A Discussion on Measurement of Springback Ratio Using Winding Bend Rig)

  • 김용우
    • 한국공작기계학회논문집
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    • 제10권2호
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    • pp.1-9
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    • 2001
  • To measure springback ratio of thin sheet or plate, winding bend rig is made. It bends a specimen with keeping its curva-ture constant and measure the bending angles before and after release of bending load. To check the performance of the bend rig, we calculated the bending moment by two ways which are based on simple beam theory. One is that the bending moment is calculated by using the results of bending test, and the other is that the moment is calculated by using the results of tensile tests. The former may entails the effect of the other is that the moment is calculated by using the results of tensile tests. The former may entails the effect of the friction between bending pin of the rig and surface of specimen, but the latter does not contain any effects of the friction since the bending moment is obtained by using tensile tests. Never-theless, the values of the two bending moments shows the same level of bending moment, which implies that the friction does not influence on the presence of friction within the scope of the test performed in this experiment. This phenomenon is explained theoretically by using moment equilibrium.

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6분력 힘/모멘트 발생장치 개발 및 평가 (Development and Evaluation of 6-components Force/Moment Generator)

  • 정홍식;주진원
    • 대한기계학회논문집A
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    • 제40권7호
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    • pp.621-628
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    • 2016
  • 본 논문에서는 다축 로드셀의 특성을 평가할 수 있는 실하중 6분력 힘 및 모멘트 발생장치를 개발하였다. 정확한 힘과 모멘트를 발생시키고 각 분력 간의 상호 작용 오차를 최소화하기 위해 몇 가지 새로운 방법을 도입하였다. 제작된 힘/모멘트 발생장치의 신뢰성을 검증하기 위하여 상용 토크셀과 본 논문에서 고안하여 제작한 양단 고정보 형태의 측정장치를 이용하여 모멘트 발생 방법을 평가하고 하중 간의 상호 측정을 수행하였다.

측정을 목적으로 시료에 변형을 가하지 않아도 되는 새로운 관성모멘트 실험 장치의 개발 (Development of a New Moment of Inertia Experiment Apparatus That Does Not Require Deformation of a Sample for Measurement Purpose)

  • 남형주
    • 공학교육연구
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    • 제23권3호
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    • pp.32-40
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    • 2020
  • A new moment of inertia experiment apparatus different from the existing one has been developed, which does not require deformation of a sample in order to fix it to the apparatus. This new experiment apparatus was able to experiment with constant-shaped objects that did not deform the samples, so that it enabled them for conducting an experiment which is close to an ideal rigid model dealt in the general physics course. The new experimental apparatus was easy and accurate in measuring the physical quantity by using the experimental principle of physical pendulum. In the results of the measurement of the moments of inertia of the six samples, all measurements were made to be accurate enough to measure with very small errors within 1%. In addition, it has been found to be useful as an experiment apparatus to understand the concept of the moment of inertia and to prove the formula for moment of inertia. Therefore, if the new moment of inertia experiment apparatus developed in this study is used in students' experiments, it is expected that students will be able to greatly increase their understanding of the concept of moment of inertia.