Search

Typical standards in aerospace applications require the ultrasonic testing (UT) of bar and wire stock with a highly reliable detection of small defects over a wide depth range in the material. Characteristic reference reflectors are flat bottom holes (FBH) with diameters smaller than 1 mm. Typically, such inspections are done with immersion tanks using a set of probes optimized for each depth. However, for industrial applications there are disadvantages such as slow scan speed, the time-consuming inlet and outlet process, complicated mechanics and significant costs of the specialized probes. This contribution demonstrates an in-line phased array inspection system with integrated multi-zone inspection, which is based on the Krautkrämer ROWA™ Ux machine. After a short description of the setup special focus is given on the implemented testing concept which is optimized with respect to a multi-zone inspection and includes a dedicated automated adjustment of the system. Furthermore, the powerful electronics allows a flexible setting of focus point, aperture size and filtering. This significantly reduces the need for special probes and by means of digital depth focusing (DDF) also the number of test shots. At the end, the flaw detectability in different depths is illustrated and achievable test speeds are presented. Moreover, external boundary conditions are discussed.

This article describes a certification procedure which includes both the qualitative and quantitative characterisation of the acoustic response of reference reflectors. It is dedicated to one-dimensional reference defects such as notches or side drilled holes but can be generalized also to two-dimensional reflectors such as flat bottom holes. At the beginning relevant measured quantities are introduced. This includes the defect homogeneity and the effective defect length which are extracted from the acoustic reflection profile. Afterwards, a setup for the performance of certification measurements is shown and the overall procedure is described. All results are summarized in a standardized protocol. At the end, the reference certification in the daily use is discussed. Due to the large database a statistic evaluation can be presented. It shows that a significant percentage of references do not fulfil the given quality criteria. The importance of a quality monitoring at different time periods is illustrated with an example of a reference notch where measurements before and after commissioning revealed a significant quality degradation. Finally, the presented method can serve as basis for updates of common standards with respect to a more complete specification of reference reflectors which will be needed due to the increasing demands on the accuracy of ultrasonic testing systems.

Non-destructive wheel inspection by means of ultrasound testing (UT) is crucial for highspeed, local or cargo trains. Any failure can lead to catastrophic events resulting in high material damage and personal injury or even fatalities. However, the inspection of train wheels is complicated due to different defect positions, which are to some part difficult to access, and a large variety of wheel geometries which are, moreover, influenced by the milage of the wheels. This article describes an industrial solution for the full-body inspection of train wheels including face, flange, web and tread. To cope with the high complexity of the inspection task, the Krautkrämer WheelStar implements advanced UT technologies in combination with a high automatization level and user-friendly controlling and inspection tools. In the first part of this article, general probe configurations and the benefits of Phased Array Ultrasonic Testing (PAUT), in particular the use of matrix probes, will be discussed. Afterwards, setup and evaluation software of the testing machine will be presented. The final part contains selected measurement results highlighting the testing capabilities. Comparative studies reveal the improvements of matrix probes. Moreover, it will be shown in which way these give access to new features such as a high precision coupling check or geometry measurements allowing a compensation of wheel wear or the identification of the wheel type (“smart probe”).

Abstract – This chapter focuses upon two contrasting features of the linguistic situation in Australia. On the one hand, together with nationhood, the past hundred or so years have seen the evolution of a distinct national variety of English in Australia recognizable also outside Australia. On the other, Australia, though a young nation, has been continuously inhabited by the various Aborigine and Torre Strait Islander communities for thousands of years. These have traditionally spoken a wide variety of different languages, some of which of great interest to linguists due to their peculiarity. Increasingly, although the use of Aborigine languages has until very recently been in steady decline, since the 1950s in particular, diverse ethnic groups speaking a variety of languages, both European and Asian, have settled in Australia. The National Policy on Languages (1987) formally directed Australia towards multilingualism and the teaching of English as a first and second language is promoted together with that of Aborigine and community languages. Consequently, Australia has been one of the first nations to try to capitalise on its own linguistic diversity, both as a means of strengthening links with the outside world and as a way of promoting a multiethnic and multicultural society at home. Australia presents then an interesting case study for those working with discourse in immigration domains who are concerned with the way that language policy (or the lack of one) may effect social harmony and serve not only as an indicator of the way that migrants are received and treated, but also a catalyst in itself for greater mutual respect.

English has become the most influential language for international discourse (Weber 1997, Graddol 2010) and it is tempting to foresee a largely monolingual future at the international level, where other languages become irrelevant. Such a simplistic view sees the adoption of English as something universal and uniform with little room for variation, local identity, or other lingua francas. Data shows that other lingua francas are not inevitably in decline. Diverse languages – e.g. Chinese, Spanish, Arabic, Hindi, French – continue to be important regionally or in certain discourse contexts (Weber 1997, Ostler 2010, Ronen et al. 2014) and on the internet. In this paper, we look at recent data from a variety of recent sources (Ronen et al. 2014,Olivié et al. 2015,) in an attempt to examine the situation regarding languages and their influences in the world today. In particular, we will attempt to take into account the fact that much language distribution is today no longer tied in with territorial dimensions. New media such as the internet, as well as mass migration between countries, have made it less easy to identify specific langugaes with precise geographical areas. Furthermore although the world is increasingly globalised, significant regional divisions still exist in the use of media (especially in the case of China) making it difficult at present to make direct comparisons about language use. In this complex scenario, it is also apparent that as English as a Lingua Franca (ELF) variations emerge and gain in influence (see Seidlhofer 2011), the identity of English will change and come to become itself a reflection of a plurilingual reality in which speakers typically have at their disposal a repertoire of different languages

Abstract - Identity chains (Hasan 1984) ˗ strings of co-referential noun phrases ˗ constitute a lesser researched area in the field of ELF, as has the more general area of cohesion (but see Hüttner 2009, Christiansen 2011). Following on the work on anaphora of such scholars as Reinhart (1983) and Cornish (1999), and on cohesion (e.g. Halliday and Hasan 1976, Halliday 2004), Christiansen (2009a/b, 2011) focuses on the link between text cohesion and discourse coherence. The interactive perspective of discourse (seen as the process of which text is the product: see Widdowson 1984: 100) is especially relevant to an ELF context of spontaneous spoken interaction. As Guido (2008) evidences, different inter-cultural concerns constitute a crucial dimension to the complex multi-code interaction. Consequently, the diverse ways in which speakers from different L1 backgrounds employ anaphors and construct identity chains are key elements in the co-construction of a dialogic text. In this case study, six extracts of transcripts taken from the VOICE corpus (2011) of conference question and answer sessions set in multicultural contexts are analysed qualitatively. The different ways that participants construct identity chains (e.g. whether they use full forms of various kinds or anaphoric pro-forms) are classified. The analysis focuses on both how individual anaphors are resolved and how relations between anaphors and antecedent triggers are encoded, and how identity chains are constructed and organized individually. The objective is to identify which kinds of noun phrase (various subtypes of full and pro-forms) are used by diverse groups of EFL speakers both in relation to their own contributions and to those of other speakers (with a threefold distinction made between the same turn of the same speaker, a different turn of the same speaker, and a different turn by a different speaker).