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Practicing Home in the Foreign

The multiple homing practices of artisan journeymen on the tramp

Dorte Jagetic Andersen and René Ejbye Pedersen

Abstract

Research in migrant practices has recognised that home crystallises into multiple forms subject to constant re-enactment when viewed from the perspective of mobile populations such as nomads and refugees. In this article, we illustrate how artisan journeymen who went on the tramp around the turn of the 20th century performed home in multiple ways when on the road and at arrival in new locations. Using a historical example, we oppose the suggestion, which is common in contemporary migration and transnational studies that recent years have witnessed a paradigmatic new way of enacting belonging. Ultimately, the argument is that instead of idealising certain notions of the traveller, or ways of practicing home, we need to keep an eye to the real-life tensions of homing and the multiplicity through which it expresses; we need to understand homing as the performance of “belonging trouble.”

Open access

Katarzyna Bizon

Abstract

Over the last decades the method of proper orthogonal decomposition (POD) has been successfully employed for reduced order modelling (ROM) in many applications, including distributed parameter models of chemical reactors. Nevertheless, there are still a number of issues that need further investigation. Among them, the policy of the collection of representative ensemble of experimental or simulation data, being a starting and perhaps most crucial point of the POD-based model reduction procedure. This paper summarises the theoretical background of the POD method and briefly discusses the sampling issue. Next, the reduction procedure is applied to an idealised model of circulating fluidised bed combustor (CFBC). Results obtained confirm that a proper choice of the sampling strategy is essential for the modes convergence however, even low number of observations can be sufficient for the determination of the faithful dynamical ROM.

Open access

Artur Waluś, Lucjan Gucma and Grzegorz Putynkowski

Abstract

The paper presents the stages of quantitative coefficient of marine seismic researches creation for the geophysical vessels towing the geophysical seismic equipment understood as system of seismic streamers where set of geophones are installed. The quality coefficient of geophysical research works is based on the mathematical model of the deviation of the position of the arrangement of streamers geophone points with relation to their idealized position. The proposed coefficient can be used during realization of seismic researches and for short-term prediction of their quality.

Open access

Juraj Králik

Abstract

This paper presents of the optimal design of the damping devices cover of reactor hall under impact of nuclear fuel container drop of type TK C30. The finite element idealization of nuclear power plant structure is used in software ANSYS. The steel pipe damper system is proposed for dissipation of the kinetic energy of the container free fall in comparison with the experimental results. The probabilistic and sensitivity analysis of the damping devices was considered on the base of the simulation methods in program AntHill using the Monte Carlo method.

Open access

S. Pietruszczak and G.N. Pande

Abstract

In this paper, a simple generalization of Darcy’s law is proposed for the description of hydraulic properties of anisotropic porous materials. The coefficient of permeability is defined as a scalarvalued function of orientation. The principal directions of permeability are determined from a fabric descriptor specifying the distribution of average pore size. An example is provided for identification of material parameters, which is based on an idealized “pipe network model”. A procedure for defining the anisotropy in strength properties, which incorporates a conceptually similar approach, is also reviewed and an illustrative example is provided.

Open access

Romain Pepy, Michel Kieffer and Eric Walter

Reliable Robust Path Planning with Application to Mobile Robots

This paper is devoted to path planning when the safety of the system considered has to be guaranteed in the presence of bounded uncertainty affecting its model. A new path planner addresses this problem by combining Rapidly-exploring Random Trees (RRT) and a set representation of uncertain states. An idealized algorithm is presented first, before a description of one of its possible implementations, where compact sets are wrapped into boxes. The resulting path planner is then used for nonholonomic path planning in robotics.

Open access

Dapeng Gu, Yulin Yang, Suwen Chen and Wenwen Su

Abstract

The paper g describes a model meant for analysis of the wear geometry of plain woven fabric composites. The referred model consists of a mathematical description of plain woven fabric based on Peirce’s model coupled with a stratified method for the solution of the wear geometry. The evolutions of the wear area ratio of weft yarn, warp yarn and matrix resin on the worn surface are simulated by MatLab software in combination of warp and weft yarn diameters, warp and weft yarn-to-yarn distances, fabric structure phases (SPs). By comparing theoretical and experimental results from the PTFE/Kevlar fabric wear experiment, it can be concluded that the model can present a trend of the component area ratio variations along with the thickness of fabric, but has a inherently large error in quantitative analysis as an idealized model.

Open access

Robert Dobrowolski

Abstract

Since the second half of the 19th century, the notion of beauty has been gradually losing its classical meaning. More and more often, our aesthetic tastes are met by that which is violent and based on creaking dissonances. Similarly, the body of a contemporary human is perceived today in a different way than it was in ancient Rome or Greece. The attractiveness of body depends now to a lesser extent than then on the arrangement of its build, appearance, and function into a harmonious whole, reflecting the idealized world of nature. The sentimentalism of the beautiful is being replaced by the aesthetics of functional machinery, and what was until recently rejected with disgust begins to be considered desirable. Not condemning all these occurrences in advance, it is worth considering if this re-aesthetization of human body is beneficial to the humanity.

Open access

Tae-Jun Kim, Beom-Seon Jang and Sung-Wook Kang

Abstract

In the present study, external restraints imposed normal to the plate during the cooling stage were determined to be effective for reduction of the angular distortion of butt-welded or fillet-welded plate. A welding analysis model under external force during the cooling stage was idealized as a prismatic member subjected to pure bending. The external restraint was represented by vertical force on both sides of the work piece and bending stress forms in the transverse direction. The additional bending stress distribution across the plate thickness was reflected in the improved inherent strain model, and a set of inherent strain charts with different levels of bending stress were newly calculated. From an elastic linear FE analysis using the inherent strain values taken from the chart and comparing them with those from a 3D thermal elasto-plastic FE analysis, welding deformation can be calculated.

Open access

J. Králik

Deterministic and probabilistic analysis of damping device resistance under impact loads from nuclear fuel container drop

This paper presents a deterministic and probabilistic solution of damping devices for the protection of the reinforced concrete structure of a nuclear power plant (NPP) from impact loads from a container of nuclear fuel of the type TK C30 drop. The finite element idealization of the building structure is used in space. The interaction soil-structure, as well as the fluid-structure of the deactivated basin is considered in space. A steel pipe damper system is proposed for the dissipation of the kinetic energy of the container in free fall. The Newmark integration method is used for the solution of the dynamic equations. The sensitivity and probabilistic analysis of the damping devices was realized using the AntHILL and ANSYS software.