title: Thermoplastic composites in sustainable construction: Topology optimisation and additive manufacturing for a recyclable and modular building system

authors: Allouche, William

subjects: Additive Manufacturing

abstract: Despite the significant environmental impact of the building sector, sustainable building practices are yet to be widely adopted. This paper describes a practical approach based on computational design and additive manufacturing (AM) to generate modular and structural walls, following design for disassembly and recyclability principles. In this research, the anisotropy of recyclable
short-fibre reinforced thermoplastic (SFRTP) composites is utilised. The proposed methodology involves starting from the building’s typology and using topology optimisation (TO) as a form-finding tool in the design of structural wall modules. The finite element analyses (FEA) guiding the TO are based on conventional building-codes used for load calculations. The TO-defined modules are then further optimised in stiffness by matching the principal stress directions with the AM printing path. Two case studies, the ground floor of a 3-storey building and a bus shelter, are used to illustrate the outcome of the approach. This comprehensive workflow generates structural elements with built-in optimised and tailored performance while enabling unique geometries that combine structural efficiency with architectural creativity.

text: Thermoplastic composites in sustainable construction: Topology optimisation and additive manufacturing for a recyclable and modular building system Despite the significant environmental impact of the building sector, sustainable building practices are yet to be widely adopted. This paper describes a practical approach based on computational design and additive manufacturing (AM) to generate modular and structural walls, following design for disassembly and recyclability principles. In this research, the anisotropy of recyclable
short-fibre reinforced thermoplastic (SFRTP) composites is utilised. The proposed methodology involves starting from the building’s typology and using topology optimisation (TO) as a form-finding tool in the design of structural wall modules. The finite element analyses (FEA) guiding the TO are based on conventional building-codes used for load calculations. The TO-defined modules are then further optimised in stiffness by matching the principal stress directions with the AM printing path. Two case studies, the ground floor of a 3-storey building and a bus shelter, are used to illustrate the outcome of the approach. This comprehensive workflow generates structural elements with built-in optimised and tailored performance while enabling unique geometries that combine structural efficiency with architectural creativity.

year: 2025

title: The energy efficiency of 8-bit low-power microcontrollers

authors: Jones, Mark Hedley

subjects: engineering

abstract: We have measured the energy cost of processing, sleeping, non-volatile memory writes and ADC measurements of six 8-bit microprocessors from three manufacturers. These measurements compare the chips directly to one another and reveal ideal operating points which can be used to reduce energy consumption.

text: The energy efficiency of 8-bit low-power microcontrollers We have measured the energy cost of processing, sleeping, non-volatile memory writes and ADC measurements of six 8-bit microprocessors from three manufacturers. These measurements compare the chips directly to one another and reveal ideal operating points which can be used to reduce energy consumption.

year: 2011

title: A late-Holocene and prehistoric record of environmental change from Lake Waikaremoana, New Zealand

authors: Newnham, Rewi M.

subjects: Palynology

abstract: Further evidence in support of a late pre-European (Polynesian) settlement of New Zealand is provided by an 1850-year-long tephropalynological record from a remote region in New Zealand's North Island. The earliest unequivocally anthropogenic forest clearance is estimated from sedimentation rates to have occurred c. 375 14C years BP (c. ad 1523–1631), although the radiocarbon chronology, shown by tephrochron ology to be erroneous due to hard-water effects, suggested this occurred c. 900 years earlier. Delineation of the anthropogenic era, and the distinction between human activity and other agents of environmental change in the pollen/spore diagram, are supported by cluster analysis and detrended correspondence analysis. Two distinct phases of forest clearance are evident during the pre-European era, reflecting local changes either in population pressure or settlement patterns. We note that the lull between the two phases of forest clearance coincides with the maximum of the ‘Little Ice Age’ within the period c. late ad 1600s to early 1800s.

text: A late-Holocene and prehistoric record of environmental change from Lake Waikaremoana, New Zealand Further evidence in support of a late pre-European (Polynesian) settlement of New Zealand is provided by an 1850-year-long tephropalynological record from a remote region in New Zealand's North Island. The earliest unequivocally anthropogenic forest clearance is estimated from sedimentation rates to have occurred c. 375 14C years BP (c. ad 1523–1631), although the radiocarbon chronology, shown by tephrochron ology to be erroneous due to hard-water effects, suggested this occurred c. 900 years earlier. Delineation of the anthropogenic era, and the distinction between human activity and other agents of environmental change in the pollen/spore diagram, are supported by cluster analysis and detrended correspondence analysis. Two distinct phases of forest clearance are evident during the pre-European era, reflecting local changes either in population pressure or settlement patterns. We note that the lull between the two phases of forest clearance coincides with the maximum of the ‘Little Ice Age’ within the period c. late ad 1600s to early 1800s.

year: 1998