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This study aims to propose a numerical modeling procedure for response analysis of elastic body floating in water and submitted to regular waves. An equivalent simplified mechanical single-degree-of-freedom system allowing to reproduce the heave movements is first developed, then the obtained lumped characteristics are used for elastic analysis of the floating body in heave motion.

First, a two-dimensional numerical model of a rigid floating body in a wave tank is implemented under DualSPHysics, an open source computational fluid dynamics (CFD) code based on smoothed particle hydrodynamics method. Then, the obtained results are exploited to derive an equivalent mechanical mass-spring-damper model. Finally, estimated equivalent characteristics are used in a structural finite element modeling of the considered body assuming elastic behavior.

Obtained results concerning the floating body displacements are represented and validated using existing experimental data in the literature. Wave forces acting on the body are also evaluated. It was found that for regular waves, it is possible to replace the complex CFD refined model by an equivalent simplified mechanical system which makes easy the use of structural finite element analysis.

The originality of this work lies in the proposed procedure to evaluate the mechanical properties of the equivalent elastic system. This allows to couple two different software tools and to take advantages of their features.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics, and publications of other similar research bodies as issued

THE general aspect of seaplanes covers a very wide field, including as it does single and twin float seaplanes and also flying boats of many different types, and with the increase of knowledge in the science of aeronautics the subject is becoming one of very great importance.

How do we write from the sensory body in ways that can convey the lived experience of the researcher and the researched, which can allow other researchers to make sense of their lived experience as well? What alternative writings could transform disembodied academia through dialogue and relational reflection? The aim of this chapter is to reflect on the value of the researcher’s embodied reflexivity in academic writing. More specifically, this chapter explores the ways in which we can write differently about organisational phenomena by experiencing aesthetic moments in the field. To accomplish this, I share examples of the aesthetic moments that I, as a researcher, experienced while undertaking three ethnographic projects: a study on professional dance, a study on academic motherhood and a study on female-canine companionship. This chapter identifies three aspects that allow the researcher to experience aesthetic moments – namely, appreciating sensory cues, writing ‘in and from the flesh’ and allowing vulnerability to flourish. Paying attention to the social micro-dynamics that exist between researchers and research phenomena and addressing the analytically marginalised experiences of researchers, therefore, allows for developing academic writing practices in more reflexive and sensory-appreciative directions.

This paper aims to study the fluid flow and forced convection heat transfer from an isothermal circular cylinder with control rods in the laminar unsteady flow regime.

The overset grid method was used for accurate simulation of the unsteady flows around different arrangements of the cylinders. Grid generation for overset grids was performed using a general orthogonal boundary fitted coordinate system. The method of solution was based on a finite volume discretization of the Navier-Stokes equations. Simulations were carried out for the Prandtl numbers of 0.7 and 7.0 with the Reynolds numbers ranging from 60 to 300.

The results indicate that the performance of multiple control rods depends strongly on the spacing ratio. Furthermore, in a manner similar to the flow patterns, four different thermal regimes were recognized based on the variations of mean Nusselt number versus G/D, as the thermal regimes follow the categories of flow regimes at different diameter ratios. However, for different Prandtl numbers, no single trend of heat transfer variation versus the spacing ratio exists for same regime.

Few studies have been conducted to investigate the heat transfer characteristics from control rods. The results of this study provide a comprehensive knowledge on the dynamical and thermal behavior of the flow around multiple cylinders.

Our primary aim is to discuss the variability that exists in the operationalization of race/ethnicity in research on genetic and biological markers. We employ Stuart Hall’s “floating signifiers” of race approach to explain the ambiguous manner in which researchers discuss the links between race and genetics.

We examine articles that use race/ethnicity and genetic or biological markers between 2000 and 2013 within three prominent genetic journals. We focused on original, empirical articles only. We utilize various race/ethnic-related search terms to obtain our sample and to categorize how terms were used.

A total of 336 articles fit our search criteria. The number of articles mentioning race/ethnicity and genetic or biological information increased over the time. A significant percentage of publications base their research on whites only. When discussions of race are included in studies, scientists often use multiple categories of race/ethnicity without much explanation.

We omit non-research articles and commentary for each journal, which could contain important discussions regarding race and genetics. This work highlights how race/ethnicity can vary in application and interpretation.

Our discussion of race/ethnicity as “floating signifiers” adds a layer of complexity to the longstanding debate regarding the importance of race/ethnicity in genetic research. The “floating” nature of race/ethnicity underlines how subjective the characterizations of samples are and how possible interpretations of results for groups can impact health disparities research. Given the increased use of genetic data by social scientists, there is a need for more cross-disciplinary discussions on the race–gene relationship.

The purpose of this paper is to introduce different methods for measuring the porosity of metal foams, and especially present a new method for conveniently measuring the open porosity that has a stronger impact on a number of physical properties of the porous product.

Metal foam is a kind of material that utilizes the function of pores inside the porous body. For such materials, the porosity is an important factor or even a key factor to determine a number of the practical parameters, such as the conductivity, acoustic properties and mechanical performances. Especially, the open porosity has a stronger impact on the sound absorption, electromagnetic shielding, heat transfer of the porous product, as well as the performances of using the internal pore surface. Therefore, it would be meaningful to find the simple and convenient to well measure the open porosity of metal foams.

In the present new method, the open porosity can be obtained directly by different volume parameters of the porous sample, while it can only by some weight indexes of the porous sample in other measuring methods.

The characteristic of this new method makes the measurement simpler and more convenient in this new method than in the other methods.

THE purpose of this paper is to give some account of the work on spinning and the progress which has been made since S. B. Gates and L. W. Bryant presented their paper to the Society, which was published in more comprehensive form by the Aeronautical Research Committee as R. & M. 1001.