scholarly journals Bifurcation of elastic solids with sliding interfaces

2018 ◽  
Vol 474 (2209) ◽  
pp. 20170681 ◽  
Author(s):  
D. Bigoni ◽  
N. Bordignon ◽  
A. Piccolroaz ◽  
S. Stupkiewicz
Keyword(s):  
Ad Hoc ◽  
Normal Component ◽  
Tangential Component ◽  
Small Scale ◽  
Elastic Solids ◽  
Interfacial Conditions ◽  
Sliding Interfaces ◽  
Set Up ◽  
Exclusion Condition ◽  
Lubricated Sliding

Lubricated sliding contact between soft solids is an interesting topic in biomechanics and for the design of small-scale engineering devices. As a model of this mechanical set-up, two elastic nonlinear solids are considered jointed through a frictionless and bilateral surface, so that continuity of the normal component of the Cauchy traction holds across the surface, but the tangential component is null. Moreover, the displacement can develop only in a way that the bodies in contact do neither detach, nor overlap. Surprisingly, this finite strain problem has not been correctly formulated until now, so this formulation is the objective of the present paper. The incremental equations are shown to be non-trivial and different from previously (and erroneously) employed conditions. In particular, an exclusion condition for bifurcation is derived to show that previous formulations based on frictionless contact or ‘spring-type’ interfacial conditions are not able to predict bifurcations in tension, while experiments—one of which, ad hoc designed, is reported—show that these bifurcations are a reality and become possible when the correct sliding interface model is used. The presented results introduce a methodology for the determination of bifurcations and instabilities occurring during lubricated sliding between soft bodies in contact.

scholarly journals Territorial Connection and Cohesion - The Case of Agrigento Inland Area

2014 ◽  
Vol 11 ◽  
pp. 41-46
Author(s):  
Gerlandina Prestia ◽  
Valeria Scavone
Keyword(s):  
Social Relations ◽  
Ad Hoc ◽  
Small Scale ◽  
World Population ◽  
Horizon 2020 ◽  
Program Schedule ◽  
New Development ◽  
Peripheral Areas ◽  
Set Up ◽  
The City

The Europe 2020 strategy and the Horizon 2020 program can begin a real path about the role that the city will be able play for a new development. Usually, it is in the cities that are intensifying tangible and intangible social relations and, given that they focused almost 70% of the world population, it is clear that the city must begin to start any development scenario: the problems / opportunities related to the management of natural resources, energy to move. The culture is a «primary factor of urban creativity (...), the city's identity that has its roots the program schedule of history and extends its branches in the future» [4], awaiting a new model of development local self-sustainable combining protection, conservation, enhancement of resources and economic recovery. In Sicily, the small cities are located, mostly, in the inland, hilly or mountainous areas, where live, again, abandonment, isolation and fragmentation, unlike the coastal urban area, more dynamic, includes the metropolitan areas and the most important towns. In this context, we examined the case of the region in Agrigento. The present study was conducted on all municipalities but not on those outermost and peripheral areas which are more distant from the pole and longer subject to the problems typical of these areas. The vision proposes a multi-layered and multi-dimensional territory characterized by infrastructure networks, networks of settlement, economic and social formations, set up with a multi-scale approach as required by the paradigm of sustainability, «a regional strategy for the medium-long-term» and, on the small scale, the answer «to ad hoc needs». In the case of the region of Agrigento, it is more appropriate deal in about the mobility and not about the transport, to move from a logic of exclusive government of the offer, a demand, through projects and policies that promote use integrated soil, actions to promote intermodality, projects to improve the construction of circuits safe mobility. To start virtuous dynamics of their cooperation, therefore, the contribution aims to intervene with a reticular approach, with a strong identity value, leading to a free physical and virtual so that, combining protection, exploitation of resources, services and economic development, in such small municipalities be returned liveability and attractiveness.

scholarly journals Modification of a Solar Thermal Collector to Promote Heat Transfer inside an Evacuated Tube Solar Thermal Absorber

2021 ◽  
Vol 11 (9) ◽  
pp. 4100
Author(s):  
Rasa Supankanok ◽  
Sukanpirom Sriwong ◽  
Phisan Ponpo ◽  
Wei Wu ◽  
Walairat Chandra-ambhorn ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Heat Pipe ◽  
Solar Thermal ◽  
Heat Transfer Fluid ◽  
Small Scale ◽  
Medium Temperature ◽  
Change Behavior ◽  
Set Up ◽  
Evacuated Tube ◽  
Heating Medium

Evacuated-tube solar collector (ETSC) is developed to achieve high heating medium temperature. Heat transfer fluid contained inside a copper heat pipe directly affects the heating medium temperature. A 10 mol% of ethylene-glycol in water is the heat transfer fluid in this system. The purpose of this study is to modify inner structure of the evacuated tube for promoting heat transfer through aluminum fin to the copper heat pipe by inserting stainless-steel scrubbers in the evacuated tube to increase heat conduction surface area. The experiment is set up to measure the temperature of heat transfer fluid at a heat pipe tip which is a heat exchange area between heat transfer fluid and heating medium. The vapor/ liquid equilibrium (VLE) theory is applied to investigate phase change behavior of the heat transfer fluid. Mathematical model validated with 6 experimental results is set up to investigate the performance of ETSC system and evaluate the feasibility of applying the modified ETSC in small-scale industries. The results indicate that the average temperature of heat transfer fluid in a modified tube increased to 160.32 °C which is higher than a standard tube by approximately 22 °C leading to the increase in its efficiency by 34.96%.

Numerical Study of Methane and Air Combustion Inside Heat-Recirculating Combustors

2013 ◽  
Author(s):  
Yanxia Li ◽  
Zhongliang Liu ◽  
Yan Wang ◽  
Jiaming Liu
Keyword(s):  
Gas Flow ◽  
Numerical Study ◽  
Convection Heat Transfer ◽  
Central Area ◽  
Small Scale ◽  
Inlet Velocity ◽  
Strong Convection ◽  
Simulation Results ◽  
Lean Fuel ◽  
Set Up

A numerical model on methane/air combustion inside a small Swiss-roll combustor was set up to investigate the flame position of small-scale combustion. The simulation results show that the combustion flame could be maintained in the central area of the combustor only when the speed and equivalence ratio are all within a narrow and specific range. For high inlet velocity, the combustion could be sustained stably even with a very lean fuel and the flame always stayed at the first corner of reactant channel because of the strong convection heat transfer and preheating. For low inlet velocity, small amounts of fuel could combust stably in the central area of the combustor, because heat was appropriately transferred from the gas to the inlet mixture. Whereas, for the low premixed gas flow, only in certain conditions (Φ = 0.8 ～ 1.2 when ν0 = 1.0m/s, Φ = 1.0 when ν0 = 0.5m/s) the small-scale combustion could be maintained.

Advancing the Agenda of the Confederation of Trade Unions on the Prevention of Sexual Violence in the World of Work in Indonesia

2021 ◽  
Vol 26 (1) ◽  
pp. 63
Author(s):  
Atnike Nova Sigiro
Keyword(s):  
Sexual Violence ◽  
Gender Equality ◽  
Trade Union ◽  
Trade Unions ◽  
Ad Hoc ◽  
Gender Based Violence ◽  
The World ◽  
Gender Based ◽  
And Gender ◽  
Set Up

<p>This article was formulated based on interviews with 5 (five) trade union confederations from a number of confederations in Indonesia, namely: Konfederasi Serikat Pekerja Nasional (KSPN), Konfederasi Sarikat Buruh Muslimin Indonesia (KSarbumusi), Konfederasi Serikat Buruh Seluruh Indonesia (KSBSI), Konfederasi Serikat Pekerja Indonesia (KSPI), and Konfederasi Kongres Aliansi Serikat Buruh Indonesia (KKASBI). This article seeks to explore the efforts made by the trade union confederation in promoting gender equality - specifically in advancing the agenda for the prevention and elimination of sexual violence in the world of work. This article was compiled based on research with a qualitative approach, with data collection methods through interviews and literature studies. The results of this study found that the confederations interviewed had already set up internal structures that have specific functions on issues related to gender equality, gender-based violence, and women’s empowerment; although still limited and on ad-hoc basis. This research also finds that the role of the trade union confederation is particularly prominent in advocating policies related to sexual violence and gender-based violence in the world of work, such as advocating the Bill on the Elimination of Sexual Violence, and the ratification of the ILO Convention No. 190 on Violence and Harassment.</p>

scholarly journals Fictive Deixis, Direct Discourse, and Viewpoint Networks

2021 ◽  
Vol 6 ◽  
Author(s):  
Barbara Dancygier
Keyword(s):  
Composite Structure ◽  
Ad Hoc ◽  
Conceptual Structure ◽  
Political Campaigns ◽  
Direct Discourse ◽  
Close Analysis ◽  
Mental Spaces ◽  
Set Up ◽  
Tight Correlation ◽  
Speech Situation

This paper proposes a renewed and more textured understanding of the relation between deixis and direct discourse, grounded in a broader range of genres and reflecting contemporary multimodal usage. I re-consider the phenomena covered by the concept of deixis in connection to the speech situation, and, by extension, to the category of Direct Discourse, in its various functions. I propose an understanding of Direct Discourse as a construction which is a correlate of Deictic Ground. Relying on Mental Spaces Theory and the apparatus it makes available for a close analysis of viewpoint networks, I analyze examples from a range of discourse genres - textual, visual and multimodal, such as literature, political campaigns, internet memes and storefront signs. These discourse contexts use Direct Discourse Constructions but usually lack a fully profiled Deictic Ground. I propose that in such cases the Deictic Ground is not a pre-existing conceptual structure, but rather is set up ad hoc to construe non-standard uses of Direct Discourse–I refer to such construals as Fictive Deictic Grounds. In that context, I propose a re-consideration of the concept of Direct Discourse, to explain its tight correlation with the concept of deixis. I also argue for a treatment of Deictic Ground as a composite structure, which may not be fully profiled in each case, while participating in the construction of viewpoint configurations.

scholarly journals Transient climate simulations of the deglaciation 21–9 thousand years before present; PMIP4 Core experiment design and boundary conditions

2015 ◽  
Vol 8 (10) ◽  
pp. 9045-9102 ◽  
Author(s):  
R. F. Ivanovic ◽  
L. J. Gregoire ◽  
M. Kageyama ◽  
D. M. Roche ◽  
P. J. Valdes ◽  
...  
Keyword(s):  
Working Group ◽  
Ad Hoc ◽  
Climate Models ◽  
Ice Sheet ◽  
Before Present ◽  
Last Deglaciation ◽  
Transient Simulations ◽  
The Last Deglaciation ◽  
Set Up ◽  
Core Simulation

Abstract. The last deglaciation, which marked the transition between the last glacial and present interglacial periods, was punctuated by a series of rapid (centennial and decadal) climate changes. Numerical climate models are useful for investigating mechanisms that underpin the events, especially now that some of the complex models can be run for multiple millennia. We have set up a Paleoclimate Modelling Intercomparison Project (PMIP) working group to coordinate efforts to run transient simulations of the last deglaciation, and to facilitate the dissemination of expertise between modellers and those engaged with reconstructing the climate of the last 21 thousand years. Here, we present the design of a coordinated Core simulation over the period 21–9 thousand years before present (ka) with time varying orbital forcing, greenhouse gases, ice sheets, and other geographical changes. A choice of two ice sheet reconstructions is given, but no ice sheet or iceberg meltwater should be prescribed in the Core simulation. Additional focussed simulations will also be coordinated on an ad-hoc basis by the working group, for example to investigate the effect of ice sheet and iceberg meltwater, and the uncertainty in other forcings. Some of these focussed simulations will focus on shorter durations around specific events to allow the more computationally expensive models to take part.

scholarly journals Torsion-shear behaviour at the interfaces of rigid interlocking blocks in masonry assemblages: experimental investigation and analytical approaches

2021 ◽  
Vol 54 (3) ◽  
Author(s):  
Claudia Casapulla ◽  
Elham Mousavian ◽  
Luca Argiento ◽  
Carla Ceraldi ◽  
Katalin Bagi
Keyword(s):  
Experimental Investigation ◽  
Ad Hoc ◽  
Pure Shear ◽  
Shear Capacity ◽  
Shear Behaviour ◽  
Main Body ◽  
Shear Failures ◽  
Set Up ◽  
External Forces ◽  
Analytical Approaches

AbstractIncreasing interest has recently been devoted to interlocking blocks/interfaces capable to enhance the sliding resistance of masonry joints to external forces. In this framework, this paper deals with the assessment of the torsion-shear capacity of the contact interface between the lock and the main body of an interlocking block, assumed to have a cohesive behaviour. The interlocking block is a rigid unit which, on its faces, have square cuboidal locks keeping the adjacent/overlapped blocks together and preventing blocks from sliding. Two numerical approaches and a novel ad hoc experimental investigation are proposed to simulate the torsion-shear behaviour by applying eccentrical shear forces to the lock. First, concave, convex and corrected concave formulations provided by the literature for assemblages of rigid blocks with conventional planar joints are extended to model the interlocking block behaviour. Then, according to a second approach based on the discrete element method, the concave-shaped interlocking block is modelled by convex polyhedrons representing the lock and the main body of the block, considered as individual rigid units stacked over each other with a cohesive contact in between. A novel experimental investigation on the limiting pure shear and torsion-shear combinations at the lock interface made of cohesive material is also presented. Two different mortars were chosen to make the specimens, which were casted using 3D printed moulds, and different test configurations were set up to simulate shear and torsion-shear failures. The analytical and numerical results are compared with each other and against the experimental ones, with interesting remarks on the application of the different approaches.

scholarly journals Le tribunal pénal international pour le Rwanda - La justice trahie (Note)

2005 ◽  
Vol 27 (4) ◽  
pp. 827-840
Author(s):  
John Philpot
Keyword(s):  
International Law ◽  
Ad Hoc ◽  
International Criminal ◽  
Military Intervention ◽  
International Criminal Tribunal ◽  
International Humanitarian Law ◽  
Humanitarian Law ◽  
Legal Requirements ◽  
Real Issue ◽  
Set Up

On November 8,1994, the Security Council of the United Nations adopted Resolution 955 creating an ad hoc international criminal tribunal to judge individuals responsible for violations of international humanitarian law committed in Rwanda between January 1, 1994 and December 31, 1994. In its form and structure, the Tribunal does not respect basic legal requirements required of a tribunal set up in international law. Us mandate - limited in time, in scope of potential indictment, and in jurisdiction to violations of international humanitarian law - mil prevent any light from being shed on the real issue raised by the Rwandan conflict, namely that of armed military intervention in Rwanda from Uganda. It will likely lead to the reinforcement of a one-sided view of the crisis in Rwanda and legitimate further unilateral interventionist policies in Africa and elsewhere. The Tribunal will institutionalize the de facto impunity for the members and supporters of the present government of Rwanda who undoubtedly committed many serious crimes between October 1, 1990 and the present.

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