scholarly journals Explicit Overturning Limit of Rigid Block Using Triple and Pseudo-Triple Impulses Under Critical Near-Fault Ground Motions

2021 ◽  
Vol 7 ◽  
Author(s):  
Sae Homma ◽  
Kunihiko Nabeshima ◽  
Izuru Takewaki

An explicit limit for the overturning of a rigid block is derived on the input level of the triple impulse and the pseudo-triple impulse as a modified version of the triple impulse that are a substitute of a near-fault forward-directivity ground motion. The overturning behavior of the rigid block is described by applying the conservation law of angular momentum and the conservation law of mechanical energy (kinetic and potential). The initial velocity of rotation after the first impulse and the change of rotational velocity after the impact on the floor due to the movement of the rotational center are determined by using the conservation law of angular momentum. The maximum angle of rotation after the first impulse is obtained by the conservation law of mechanical energy. The change of rotational velocity after the second impulse is also characterized by the conservation law of angular momentum. The maximum angle of rotation of the rigid block after the second impulse, which is mandatory for the computation of the overturning limit, is also derived by the conservation law of mechanical energy. This allows us to prevent from computing complex non-linear time-history responses. The critical timing of the second impulse (also the third impulse timing to the second impulse) is featured by the time of impact after the first impulse. As in the case of the double impulse, the action of the second impulse just after the impact is employed as the critical timing. It is induced from the explicit expression of the critical velocity amplitude limit of the pseudo-triple impulse that its limit is slightly larger than the limit for the double impulse. Finally, it is found that, when the third impulse in the triple impulse is taken into account, the limit input velocity for the overturning of the rigid block becomes larger than that for the pseudo-triple impulse. This is because the third impulse is thought to prevent the overturning of the rigid block by giving an impact toward the inverse direction of the vibration of the rigid block.

1998 ◽  
Vol 65 (3) ◽  
pp. 719-726 ◽  
Author(s):  
S. Djerassi

This paper is the third in a trilogy dealing with simple, nonholonomic systems which, while in motion, change their number of degrees-of-freedom (defined as the number of independent generalized speeds required to describe the motion in question). The first of the trilogy introduced the theory underlying the dynamical equations of motion of such systems. The second dealt with the evaluation of noncontributing forces and of noncontributing impulses during such motion. This paper deals with the linear momentum, angular momentum, and mechanical energy of these systems. Specifically, expressions for changes in these quantities during imposition and removal of constraints are formulated in terms of the associated changes in the generalized speeds.


Author(s):  
Roberto Lozano

A theoretical model that relates the rotational Doppler shift of a photon and the rotational velocity of the lenses traversed by the beam of light, is presented. The mathematical relation, which is resolved in the context of a four-dimensional Minkowski flat spacetime and Cartesian coordinates, relates the rotational Doppler effect of a circularly polarized electromagnetic wave, caused by the transfer of spin angular momentum from a rotating object (lenses), with the coordinate acceleration of the rotating object, in the counter-propagating direction in which the photons move, and its angular velocity. From the analysis of the solved equation, it can be considered the generated coordinate acceleration and the theoretical possibility that it was obtained from the mechanical energy of a rotating object traversed by a beam of light, which, in turn, would generate a coordinate acceleration difference in the parallel and counter-propagating direction in which the photons move.


2016 ◽  
Vol 13 (1) ◽  
pp. 159-168
Author(s):  
Bayram Unal

This study aims at understanding how the perceptions about migrants have been created and transferred into daily life as a stigmatization by means of public perception, media and state law implementations.  The focus would be briefly what kind of consequences these perceptions and stigmatization might lead. First section will examine the background of migration to Turkey briefly and make a summary of migration towards Turkey by 90s. Second section will briefly evaluate the preferential legal framework, which constitutes the base for official discourse differentiating the migrants and implementations of security forces that can be described as discriminatory. The third section deals with the impact of perceptions influential in both formation and reproduction of inclusive and exclusive practices towards migrant women. Additionally, impact of public perception in classifying the migrants and migratory processes would be dealt in this section.


2010 ◽  
Vol 95 (Supplement 1) ◽  
pp. Fa25-Fa25
Author(s):  
N. Farah ◽  
M. Kennelly ◽  
V. Donnelly ◽  
B. Stuart ◽  
M. Turner

Author(s):  
Daniel B. Kelly

This chapter analyzes how law and economics influences private law and how (new) private law is influencing law and economics. It focuses on three generation or “waves” within law and economics and how they approach private law. In the first generation, many scholars took the law as a starting point and attempted to use economic insights to explain, justify, or reform legal doctrines, institutions, and structures. In the second generation, the “law” at times became secondary, with more focus on theory and less focus on doctrines, institutions, and structures. But this generation also relied increasingly on empirical analysis. In the third generation, which includes scholars in the New Private Law (NPL), there has been a resurgence of interest in the law and legal institutions. To be sure, NPL scholars analyze the law using various approaches, with some more and some less predisposed to economic analysis. However, economic analysis will continue to be a major force on private law, including the New Private Law, for the foreseeable future. The chapter considers three foundational private law areas: property, contracts, and torts. For each area, it discusses the major ideas that economic analysis has contributed to private law, and surveys contributions of the NPL. The chapter also looks at the impact of law and economics on advanced private law areas, such as business associations, trusts and estates, and intellectual property.


2020 ◽  
Vol 36 (4) ◽  
pp. 1043-1055
Author(s):  
Gaby Umbach

This article1 offers reflections on the use of data as evidence in 21st century policy-making. It discusses the concept of evidence-informed policy-making (EIPM) as well as the governance and knowledge effects of data as evidence. With this focus, it interlinks the analysis of statistics and politics. The paper first introduces the concept of EIPM and the impact of evidence use. Here it focusses on science and knowledge as resources in policy-making, on the institutionalisation of science advice and on the translation of information and knowledge into evidence. The second part of the article reflects on data as evidence. This part concentrates on abstract and concrete functions of data as governance tools in policy-making, on data as a robust form of evidence and on the effects of data on knowledge and governance. The third part highlights challenges for data as evidence in policy-making, among them, politicisation, transparency, and diversity as well as objectivity and contestation. Finally, the last part draws conclusions on the production and use of data as evidence in EIPM. Throughout the second part of the reflections, reference is made to Walter Radermacher’s 2019 matrix of actors and activities related to data, facts, and policy published in this journal.


2021 ◽  
pp. 019791832110002
Author(s):  
Matteo Vergani ◽  
Ihsan Yilmaz ◽  
Greg Barton ◽  
James Barry ◽  
Galib Bashirov ◽  
...  

This IMR Research Note examines the impact of the level of bonding social capital on access to employment among newly arrived Afghan refugees in Victoria (Australia). Based on a mixed-methods analysis of biographical interviews with 80 Afghan refugees, it examines their use of social capital, year by year, during the first three years after their arrival. Our analysis shows that higher levels of bonding social capital are associated with greater success in finding employment during the first and second year of settlement. In the third year, however, bonding social capital for Afghan refugees in Victoria is no longer a significant predictor of employment. This Research Note helps clarify inconsistent findings in the literature on the effects of social capital on obtaining employment by suggesting that bonding social capital’s impact on refugee employment success changes significantly across the first three years after arrival. This finding has important implications for migration policy and the prioritization of resources toward services for newly arrived refugees.


2009 ◽  
Vol 79 (4) ◽  
pp. 747-754 ◽  
Author(s):  
Michael Knösel ◽  
Klaus Jung ◽  
Liliam Gripp-Rudolph ◽  
Thomas Attin ◽  
Rengin Attin ◽  
...  

Abstract Objective: To test the null hypothesis that third-order measurements are not correlated to lingual incisor features seen on radiographs. Material and Methods: The lateral headfilms of 38 untreated, norm-occlusion subjects without incisor abrasions or restorations were used for third-order measurements of upper and lower central incisors and assessment of the inclination of four sites suitable for lingual bracket placement with reference to the occlusal plane perpendicular. Lingual sections were determined by the tangents at the incisal fossa (S1), at the transition plateau between incisal fossa and the cingulum (S2), by a constructed line reaching from the incisal tip to the cingulum (S3), and by a tangent at the cingulum convexity (S4). Third-order angles were also assessed on corresponding dental casts using an incisor inclination gauge. Regression analysis was performed using the third-order measurements of both methods as the dependent variables and the inclination of the lingual enamel sections (S1, S2, S3, S4) as the independent variables. Results: The null hypothesis was rejected. For the most common bracket application sites located on the lingual shovel (S1 and S2), third-order inclination changes of 0.4–0.7 degrees are expected for each degree of change in the inclination of the lingual surface. The impact of bracket placement errors on third-order angulation is similar between sections S1 and S2 and the cingulum convexity (S4). Section S3 proved to be least affected by interindividual variation. Conclusion: The third-order measurements are correlated to lingual incisor features. Accordingly, third-order changes resulting from variation in lingual bracket placement can be individually predicted from radiographic assessments.


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