title: Characterisation and modelling of loudspeaker cone resonance

authors: Taberner, Andrew James

abstract: Loudspeaker cone resonance (“cone break-up”) is a fundamental cause of ripple in the electrical impedance and sound pressure responses of electrodynamic loudspeakers. In this thesis, the dependence of the characteristics of loudspeaker cone resonances on the material properties and thickness profile of the cone is extensively determined by creating 2D and 3D finite element models of a 6½-inch polypropylene-cone loudspeaker. Techniques for adjusting the resonant characteristics of loudspeaker cones by varying the material properties and thickness profile of the cone are explored and summarised.

The effect of cutting narrow slots through the surface of a loudspeaker cone is determined using 3D finite element modelling techniques, and cone slots are shown to have a large influence on the characteristics of the loudspeaker cone. A slotted loudspeaker cone with desirable impedance and sound pressure response characteristics is modelled and constructed. The measured response of the slotted loudspeaker is demonstrated to be a significant improvement over the characteristics of an unslotted loudspeaker.

text: Characterisation and modelling of loudspeaker cone resonance Loudspeaker cone resonance (“cone break-up”) is a fundamental cause of ripple in the electrical impedance and sound pressure responses of electrodynamic loudspeakers. In this thesis, the dependence of the characteristics of loudspeaker cone resonances on the material properties and thickness profile of the cone is extensively determined by creating 2D and 3D finite element models of a 6½-inch polypropylene-cone loudspeaker. Techniques for adjusting the resonant characteristics of loudspeaker cones by varying the material properties and thickness profile of the cone are explored and summarised.

The effect of cutting narrow slots through the surface of a loudspeaker cone is determined using 3D finite element modelling techniques, and cone slots are shown to have a large influence on the characteristics of the loudspeaker cone. A slotted loudspeaker cone with desirable impedance and sound pressure response characteristics is modelled and constructed. The measured response of the slotted loudspeaker is demonstrated to be a significant improvement over the characteristics of an unslotted loudspeaker.

year: 1998

title: Network of positive affect and depression in older adults

authors: Hopkins, Ella G.

abstract: Background
Depression in older adults poses significant health challenges, yet the protective role of positive affect remains understudied. This research examined the complex network of positive affect and depression in older adults using advanced network analysis techniques to identify potential targets for intervention.
Methods
Bayesian Gaussian Graphical Models and Directed Acyclic Graph modelling were used to analyse associations between ten positive affect variables and depression. Exploratory and confirmatory network analyses ensured stability and node predictability quantified variable influence. Stepwise linear regression confirmed whether specific positive affective variables identified in the networks predicted lower depression scores.
Results
Enthusiasm emerged as a key ancestral node with the highest predictability (R2 = 0.65), initiating cascades of positive affect. A primary pathway to depression was identified through feeling active (strength = 1.00, direction = 0.79), with an indirect pathway from feeling enthusiastic via active (strength = 0.98, direction = 0.79) to depression (strength = 1.00, direction = 0.79). Confirmatory longitudinal analysis showed that feeling active and enthusiastic consistently predicted lower depression scores (p < 0.001). The network structure remained stable across analyses.
Conclusions
Enthusiasm was identified as a central catalyst in the positive affect network, revealing clear pathways through which positive affect may protect against depression in older adults. Enhancing enthusiastic and active emotional experiences emerged as potential effective, nonpharmacological strategies for preventing and treating depression in older adults.

text: Network of positive affect and depression in older adults Background
Depression in older adults poses significant health challenges, yet the protective role of positive affect remains understudied. This research examined the complex network of positive affect and depression in older adults using advanced network analysis techniques to identify potential targets for intervention.
Methods
Bayesian Gaussian Graphical Models and Directed Acyclic Graph modelling were used to analyse associations between ten positive affect variables and depression. Exploratory and confirmatory network analyses ensured stability and node predictability quantified variable influence. Stepwise linear regression confirmed whether specific positive affective variables identified in the networks predicted lower depression scores.
Results
Enthusiasm emerged as a key ancestral node with the highest predictability (R2 = 0.65), initiating cascades of positive affect. A primary pathway to depression was identified through feeling active (strength = 1.00, direction = 0.79), with an indirect pathway from feeling enthusiastic via active (strength = 0.98, direction = 0.79) to depression (strength = 1.00, direction = 0.79). Confirmatory longitudinal analysis showed that feeling active and enthusiastic consistently predicted lower depression scores (p < 0.001). The network structure remained stable across analyses.
Conclusions
Enthusiasm was identified as a central catalyst in the positive affect network, revealing clear pathways through which positive affect may protect against depression in older adults. Enhancing enthusiastic and active emotional experiences emerged as potential effective, nonpharmacological strategies for preventing and treating depression in older adults.

year: 2026

title: Kāinga tahi, kāinga rua: A kaupapa Māori response of Te Puea Memorial Marae.

authors: Lee-Morgan, Jenny Bol Jun

abstract: In the winter of 2016, Te Puea Memorial Marae (TPMM) initiated a kaupapa Māori marae-led response, opening their doors to vulnerable whānau seeking emergency housing. Following in the legacy of Te Puea Herangi,¹ the marae answered the call of homeless whānau in Auckland and in doing so disrupted the dominant Auckland housing narrative where the government had until that time refused to acknowledge homelessness as a serious issue. In the full view of the media, TPMM not only made the reality of homelessness visible by caring for 181 people (of all ethnicities and cultural backgrounds), but named the housing situation in Auckland as a ‘crisis’. ²

text: Kāinga tahi, kāinga rua: A kaupapa Māori response of Te Puea Memorial Marae. In the winter of 2016, Te Puea Memorial Marae (TPMM) initiated a kaupapa Māori marae-led response, opening their doors to vulnerable whānau seeking emergency housing. Following in the legacy of Te Puea Herangi,¹ the marae answered the call of homeless whānau in Auckland and in doing so disrupted the dominant Auckland housing narrative where the government had until that time refused to acknowledge homelessness as a serious issue. In the full view of the media, TPMM not only made the reality of homelessness visible by caring for 181 people (of all ethnicities and cultural backgrounds), but named the housing situation in Auckland as a ‘crisis’. ²

year: 2017