title: Tube shape selection for heat recovery from particle-laden exhaust gas streams

authors: Walmsley, Timothy Gordon

abstract: Heat recovery from exhaust gas streams is applicable to a wide variety of industries. Two problems encountered in exhaust gas heat recovery are: the high heat transfer resistance of gases and the presence of entrained particulate matter, which can limit the use of extended surface area. Standard heat exchangers use round tube. This study uses Computational Fluid Dynamics (CFD) to investigate whether round or another shape is the best tube selection for exhaust heat recovery.
Tube shape rankings are based on taking into account heat transfer, gas flow resistance and foulability. Foulability is inferred from the average wall shear stress around the front or back of each shape. An estimated asymptotic fouling resistance is used to calculate an equivalent fouled j factor, jf. CFD results suggest the best tube for exhaust heat recovery is an elliptical tube. The ellipse shape produced j/f and jf/f ratios (where f is the tube bank friction factor) over 1.5 times larger than that of standard round tube. A flattened round tube is also promising and may be the practical and economic optimum.

text: Tube shape selection for heat recovery from particle-laden exhaust gas streams Heat recovery from exhaust gas streams is applicable to a wide variety of industries. Two problems encountered in exhaust gas heat recovery are: the high heat transfer resistance of gases and the presence of entrained particulate matter, which can limit the use of extended surface area. Standard heat exchangers use round tube. This study uses Computational Fluid Dynamics (CFD) to investigate whether round or another shape is the best tube selection for exhaust heat recovery.
Tube shape rankings are based on taking into account heat transfer, gas flow resistance and foulability. Foulability is inferred from the average wall shear stress around the front or back of each shape. An estimated asymptotic fouling resistance is used to calculate an equivalent fouled j factor, jf. CFD results suggest the best tube for exhaust heat recovery is an elliptical tube. The ellipse shape produced j/f and jf/f ratios (where f is the tube bank friction factor) over 1.5 times larger than that of standard round tube. A flattened round tube is also promising and may be the practical and economic optimum.

year: 2011-12-01

title: Theories of governance and pacific microstates: The cautionary tale of Tuvalu.

authors: Goldsmith, Michael

subjects: governance

abstract: This paper questions the popularity of governance frameworks in explaining development failures and proposing new models of development for Pacific states. Such popularity is attributed to how problems are selected and framed (the doomsday scenario of demographic and environmental collapse, weakening of the state, and an upsurge in corruption) but also, and most importantly, to the recent hegemony of neo-liberal theory in political economy. Taking the MIRAB microstate of Tuvalu as a counterexample, each of those pillars of governance theory is seen to be lacking or to require a more nuanced form of understanding. A brief analysis of how the dominant Protestant church fits into traditional and modern systems of administration illustrates the complexity of local issues. The essay concludes with a discussion of how the neo-liberal governance orthodoxy lacks the critical insight into power and agency afforded by Foucault's concept of governmentality.

text: Theories of governance and pacific microstates: The cautionary tale of Tuvalu. This paper questions the popularity of governance frameworks in explaining development failures and proposing new models of development for Pacific states. Such popularity is attributed to how problems are selected and framed (the doomsday scenario of demographic and environmental collapse, weakening of the state, and an upsurge in corruption) but also, and most importantly, to the recent hegemony of neo-liberal theory in political economy. Taking the MIRAB microstate of Tuvalu as a counterexample, each of those pillars of governance theory is seen to be lacking or to require a more nuanced form of understanding. A brief analysis of how the dominant Protestant church fits into traditional and modern systems of administration illustrates the complexity of local issues. The essay concludes with a discussion of how the neo-liberal governance orthodoxy lacks the critical insight into power and agency afforded by Foucault's concept of governmentality.

year: 2005

title: Characteristics and outcomes of patients with small cell lung cancer - findings from a New Zealand SACT database

authors: Lawrenson, Ross

abstract: Background Small Cell Lung Cancer (SCLC) SCLC generally presents late and is treated with systemic anti-cancer treatment (SACT). Māori are over represented in Lung Cancer statistics but disparities between Māori and non-Māori in patterns of care and survival from SCLC have not been previously reported. 
Methods We used the custom-built SACT database collected by the Oncology Department at Waikato Hospital NZ, which recorded comprehensive lung cancer patient factors and SACT regimens from 2000 to 2021. We reported summary statistics to review the treatment by ethnicity, explored Kaplan Meier all-cause survival of patients, and estimated the unadjusted and adjusted odds ratios of surviving 12 months. 
Results 742 patients with SCLC were included in this study, with 43% identified as Māori. Approximately 75% of patients received SACT, and there was no difference in the uptake of SACT between Māori and non-Māori. The median survival for SCLC was 8.5 months. After adjustment, patients treated with carboplatin plus etoposide (with/without durvalumab) or cisplatin plus etoposide were 1.5 times or 4.9 times respectively more likely to survive 12 months than those without a SACT regimen.
Conclusion There was no significant evidence of disparities in patterns of care and outcomes between Māori and non-Māori with SCLC. Carboplatin/cisplatin in combination with etoposide remained the primary first line SACT regimen for patients with SCLC in this New Zealand cancer treatment centre.

text: Characteristics and outcomes of patients with small cell lung cancer - findings from a New Zealand SACT database Background Small Cell Lung Cancer (SCLC) SCLC generally presents late and is treated with systemic anti-cancer treatment (SACT). Māori are over represented in Lung Cancer statistics but disparities between Māori and non-Māori in patterns of care and survival from SCLC have not been previously reported. 
Methods We used the custom-built SACT database collected by the Oncology Department at Waikato Hospital NZ, which recorded comprehensive lung cancer patient factors and SACT regimens from 2000 to 2021. We reported summary statistics to review the treatment by ethnicity, explored Kaplan Meier all-cause survival of patients, and estimated the unadjusted and adjusted odds ratios of surviving 12 months. 
Results 742 patients with SCLC were included in this study, with 43% identified as Māori. Approximately 75% of patients received SACT, and there was no difference in the uptake of SACT between Māori and non-Māori. The median survival for SCLC was 8.5 months. After adjustment, patients treated with carboplatin plus etoposide (with/without durvalumab) or cisplatin plus etoposide were 1.5 times or 4.9 times respectively more likely to survive 12 months than those without a SACT regimen.
Conclusion There was no significant evidence of disparities in patterns of care and outcomes between Māori and non-Māori with SCLC. Carboplatin/cisplatin in combination with etoposide remained the primary first line SACT regimen for patients with SCLC in this New Zealand cancer treatment centre.

year: 2023-02-10