Josué Costa-Baptista, Edith Roland Fotsing, Jacky Mardjono, Daniel Therriault and Annie Ross
The purpose of this paper is the design and experimental investigation of compact hybrid sound-absorbing materials presenting low-frequency and broadband sound absorption.
Abstract
Purpose
The purpose of this paper is the design and experimental investigation of compact hybrid sound-absorbing materials presenting low-frequency and broadband sound absorption.
Design/methodology/approach
The hybrid materials combine microchannels and helical tubes. Microchannels provide broadband sound absorption in the middle frequency range. Helical tubes provide low-frequency absorption. Optimal configurations of microchannels are used and analytical equations are developed to guide the design of the helical tubes. Nine hybrid materials with 30 mm thickness are produced via additive manufacturing. They are combinations of one-, two- and four-layer microchannels and helical tubes with 110, 151 and 250 mm length. The sound absorption coefficient of the hybrid materials is measured using an impedance tube.
Findings
The type of microchannels (i.e. one, two or four layers), the number of rotations and the number of tubes are key parameters affecting the acoustic performance. For instance, in the 500 Hz octave band (α500), sound absorption of a 30 mm thick hybrid material can reach 0.52 which is 5.7 times higher than the α500 of a typical periodic porous material with the same thickness. Moreover, the broadband sound absorption for mid-frequencies is reasonably high with and α1000 > 0.7. The ratio of first absorption peak wavelength to structure thickness λ/T can reach 17, which is characteristic of deep-subwavelength behaviour.
Originality/value
The concept and experimental validation of a compact hybrid material combining a periodic porous structure such as microchannels and long helical tubes are original. The ability to increase low-frequency sound absorption at constant depth is an asset for applications where volume and weight are constraints.
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Dorothy Kass and Martin Sullivan
Originally written in the 1990s but unpublished, the paper is now revised; the purpose of this paper is to examine the context of the formation of the Educational Workers League…
Abstract
Purpose
Originally written in the 1990s but unpublished, the paper is now revised; the purpose of this paper is to examine the context of the formation of the Educational Workers League of NSW in 1931 with particular emphasis on the NSW Crown Employees (Teachers) Conciliation Committee and the enactment of its agreement in the worsening economic conditions of the Depression. The aims, reception and possible influence of the League on Federation policy and practice are addressed.
Design/methodology/approach
Primary source material consulted includes the minutes of the Conciliation Committee’s sittings from September 1927 to July 1929; papers relating to the Educational Workers League held in the Teachers Federation Library; and the Teachers Federation journal, Education.
Findings
The Conciliation Committee’s proceedings and outcomes had far reaching implications. The resultant salary agreement received a hostile reception from assistant teachers and fuelled distrust between assistants and headmasters. As economic depression deepened, dissatisfaction with the conservative leadership and tactics of the Federation increased. One outcome was the formation of the radical, leftist Educational Workers League by teachers, including Sam Lewis, who would later play key roles within the Federation itself.
Originality/value
While acknowledging the extensive earlier work of Bruce Mitchell, the paper contributes to a deeper understanding of teacher unionism and teacher activism in the 1920s and 1930s. Apart from brief attention by Federation historians in the 1960s and 1970s, there has been no history of the formation, reception and significance of the Educational Workers League.
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During the apartheid era many women, such as Albertina Sisulu and Lilian Ngoyi to name only two, spent time in solitary confinement. Women were punished for taking part in…
Abstract
During the apartheid era many women, such as Albertina Sisulu and Lilian Ngoyi to name only two, spent time in solitary confinement. Women were punished for taking part in political activities by being issued with banning orders or placed under house arrest. Women placed under banning orders were treated differently to men. At the Special Hearings which were organised by the Truth and Reconciliation Commission (TRC) women were provided with an opportunity to talk about their experiences as women living under apartheid instead of talking about what had happened to someone in their family. The silencing of women continued even after the new government came to power. This is clearly illustrated in the negligible space allotted to the experiences of women’s oppression and human rights violations in the hearings before the TRC. My concern that an understanding and appreciation of the suffering, oppression, political activism and contribution by South African women during apartheid will be lost to future generations is shared by Annie Coombes’s statement in her book History After Apartheid: Visual Culture and Public Memory in a Democratic South Africa (2003).
Tessa Trappes‐Lomax, Annie Ellis and Mary Fox
This is the third in a series of articles about trying to develop better evidence for a service on the health/social care interface. All are based on our experiences of carrying…
Abstract
This is the third in a series of articles about trying to develop better evidence for a service on the health/social care interface. All are based on our experiences of carrying out a comparative study of residential rehabilitation for older people. The first two dealt with methodology and implementation. Now we reflect on the completion of the project and the first stages of dissemination.
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Paula R. Dempsey, Glenda M. Insua, Annie R. Armstrong, Holly Joy Hudson, Kristyn Caragher and Mariah McGregor
This analysis of chat reference transcripts assesses differences in how librarians and graduate assistants (GAs) incorporate teaching strategies in responding to chat reference…
Abstract
Purpose
This analysis of chat reference transcripts assesses differences in how librarians and graduate assistants (GAs) incorporate teaching strategies in responding to chat reference inquiries in social sciences, health sciences, humanities, STEM and business/economics at a large, public R1 university in the United States.
Design/methodology/approach
Researchers with disciplinary assignments in five different subject domains conducted qualitative analysis of a purposive sample of 982 transcripts of chat interactions during four semesters in 2021 and 2022.
Findings
Some form of information literacy instruction (ILI) occurred in 58% of the transcripts, with slightly less teaching occurring in social sciences inquiries than in other subject areas. Of transcripts that included teaching strategies, search procedures predominated, followed by a mix of concepts and procedures, and the least with concepts only. Chat providers taught concepts specific to social sciences, health sciences and humanities, but not to STEM or business.
Research limitations/implications
The study compares transcripts at one institution; findings may be most applicable to large, research institutions that seek to incorporate ILI in online reference services.
Practical implications
Chat reference training should include best practices for ILI relevant to specific subject domains for providers without background in those disciplines and recommendations for referrals to subject specialists.
Originality/value
Existing ILI literature does not address the question of how chat providers teach concepts rooted in a specific subject domain or offer a comparison of teaching strategies employed in different disciplines, by librarians versus GAs or staff.
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Tessa Trappes‐Lomax and Annie Ellis
This is the first of two articles about evaluating a residential rehabilitation service for older people. It highlights some key principles about research on the health/social…
Abstract
This is the first of two articles about evaluating a residential rehabilitation service for older people. It highlights some key principles about research on the health/social care interface, which may be useful to others doing similar work. Here we describe the methodology and how it was chosen. In the next article we will discuss the baseline data findings.
Life studies are a rich source for further research on the role of the Afro‐American woman in society. They are especially useful to gain a better understanding of the…
Abstract
Life studies are a rich source for further research on the role of the Afro‐American woman in society. They are especially useful to gain a better understanding of the Afro‐American experience and to show the joys, sorrows, needs, and ideals of the Afro‐American woman as she struggles from day to day.
This study seeks to examine, from the viewpoint of 12 adult fiction readers who are members of book clubs, how they go about selecting fiction books to borrow from the public…
Abstract
Purpose
This study seeks to examine, from the viewpoint of 12 adult fiction readers who are members of book clubs, how they go about selecting fiction books to borrow from the public library.
Design/methodology/approach
Each participant took part in an individual, semi‐structured, face‐to‐face interview. Using Williamson's Ecological Model of Information Seeking and Use as the conceptual framework, the study examined the role that fiction readers' “internal environments” and “external contexts” played in their book choices.
Findings
The selection of fiction books at the public library occurred, to a large extent, outside it. Fiction books were selected as part of everyday life information seeking, influenced by study participants' personal characteristics and circumstances as well as sources from their everyday lives, which typically included family, friends, book club and the mass media. While the public library was the main means by which study participants obtained their fiction books, it was not the first source to which they turned for ideas on what to read.
Originality/value
The study moves from a preoccupation of readers' actions at the public library to examine, more holistically, how everyday life information sources influence their choices of fiction books at the public library. It highlights the purposive and serendipitous dimensions of book selections and also underscores the importance of recognizing trust as a determining factor in book selection.