Glimpses of Sustainability in Perth, Western Australia: Capturing and Communicating the Adaptive Capacity of Activist Groups

The root causes of unsustainability e.g. social and environmental injustice are often associated with the failure of the state or the market, and community based activism is one of the ways societies have responded to tackle the sustainability conundrum. Millions of sustainability activist groups (SAGs) are actively engaged in various social and environmental initiatives around the world. While the potential of visualisation to foster sustainability causes has been increasingly utilised, photographic narratives on adaptive capacity – the ability to secure various forms of necessary resources in changing circumstances – of SAGs have been under-represented. This paper responds to this gap and captures the glimpses of one of the longest running activisms in Perth, the state capital of Western Australia

Investigation of Hot-Spots Due to Trapped Flux in Niobium Superconducting Radiofrequency Cavities

One of the significant sources of residual losses in superconducting radio-frequency cavities is magnetic flux trapped during the cool-down due to the incomplete Messier effect. If the trapped vortices are non-uniformly distributed on the cavity surface, the temperature mapping revealed the “hot-spots” at the location of high density of pinned vortices. Here, we performed a rf test on 1.3 GHz single cell cavity with the combination of the temperature mapping system. The temperature mapping reveled the development of the hot spots with the increase in rf field inside the cavity. When magnetic field is trapped locally on the surface of cavity, the hot-spots strength increase rapidly, showing the direct correlation of vortex induced hot spot and corresponding rf loss

Evaluation of flux expulsion and flux trapping sensitivity of srf cavities fabricated from cold work Nb sheet with successive heat treatment

The main source of RF losses leading to lower quality factor of superconducting radio-frequency cavities is due to the residual magnetic flux trapped during cool-down. The loss due to flux trapping is more pronounced for cavities subjected to impurities doping. The flux trapping and its sensitivity to rf losses are related to several intrinsic and extrinsic phenomena. To elucidate the effect of re-crystallization by high temperature heat treatment on the flux trapping sensitivity, we have fabricated two 1.3 GHz single cell cavities from cold-worked Nb sheets and compared with cavities made from standard fine-grain Nb. Flux expulsion ratio and flux trapping sensitivity were measured after successive high temperature heat treatments. The cavity made from cold worked Nb showed better flux expulsion after 800 C/3h heat treatments and similar behavior when heat treated with additional 900 C/3h and 1000 C/3h. In this contribution, we present the summary of flux expulsion, trapping sensitivity, and RF results.Comment: 21st International Conference on Radio-Frequency Superconductivity (SRF 2023

Cyclic Performance of Beam-Column Joints with Extended Column Fixed at Base: Part I - Experimental Investigation

http://www.icevirtuallibrary.com/content/journals “Permission is granted by ICE Publishing to print one copy for personal use. Any other use of these PDF files is subject to reprint fees.”The seismic performance of a non-seismically detailed reinforced concrete (RC) beam–column joint with column pinned and fixed at the base is experimentally investigated in this paper. Six half-scale RC beam–column specimens were tested to study the effect of inflection point on the cyclic behaviour of beam–column sub-assemblages. The specimens were separated into two groups. The shape of specimens in the first group was cruciform; the size of the column in those specimens was varied while the size of beam was kept nearly constant. The dimensions and reinforcing detail of specimens in the second group were identical to those in the first one except that the column was extended to the footing and fixed at the base. The main variable in this study was the relative stiffness between beam and column, which affects the position of the inflection point. The test results demonstrated a significant effect of inflection point position on the load capacity, joint shear stress and failure mode

Spin and charge dynamics in [TbPc2_2]0^0 and [DyPc2_2]0^0 single molecule magnets

Magnetization, AC susceptibility and $\mu$SR measurements have been performed in neutral phthalocyaninato lanthanide ([LnPc$_2]^0$) single molecule magnets in order to determine the low-energy levels structure and to compare the low-frequency spin excitations probed by means of macroscopic techniques, such as AC susceptibility, with the ones explored by means of techniques of microscopic character, such as $\mu$SR. Both techniques show a high temperature thermally activated regime for the spin dynamics and a low temperature tunneling one. While in the activated regime the correlation times for the spin fluctuations estimated by AC susceptibility and $\mu$SR basically agree, clear discrepancies are found in the tunneling regime. In particular, $\mu$SR probes a faster dynamics with respect to AC susceptibility. It is argued that the tunneling dynamics probed by $\mu$SR involves fluctuations which do not yield a net change in the macroscopic magnetization probed by AC susceptibiliy. Finally resistivity measurements in [TbPc$_2]^0$ crystals show a high temperature nearly metallic behaviour and a low temperature activated behaviour.Comment: 8 pages, 12 figure

Power purchase agreements for risk and rent sharing in Himalayian hydropower developments

The Himalayan Rivers have an enormous hydropower potential that is still not exploited fully for the benefit of the region. Bhutan and Nepal together have an economically feasible potential of 60,000 MW of hydroelectric power generation capacity but are too weak financially to bear alone the risks associated with the development of their hydro resources. India is the only potential market for the electricity supplied from these sources. The power purchase agreement framework for the 336 MW Chukha Hydel Project in Bhutan could serve as a model with regards to the transfer of risks, management of risks, and sourcing of finance in exchange for the sharing of the economic rents associated with such projects. India undertook the costs and risks of constructing the hydroelectric dam and power plant in exchange for a reduced purchase price of electricity from the completed facility. This paper contains a financial and economic assessment of the Chukha Hydel Project. While India is in a position to exercise monopsonic power in this electricity market, this analysis shows that it is possible to have an agreement for sharing of the risks and returns between India and the Himalayan countries that is highly beneficial to all the stakeholders

Beach Erosion and Nourishment in Gold Coast: Perceptions, Policies and Prospects

The combination of ongoing urban development and forecasted impacts of the changing climate are projected to place many coastal areas at risk. One of the associated risks is beach erosion, and consequently, nourishment initiatives have become a costly sustainable development issue for local and state governments. For instance, the popular Palm Beach, a nearly four kilometres stretch of sandy beach on the southern Gold Coast in Queensland, Australia has been identified as being more susceptible to serious erosion than other beaches in the city. Consequently, the local council has spent millions of dollars on beach nourishment and is seeking ways to fund the initiative. In this context of coastal management, an exploratory pilot research project was undertaken to examine the question of - “how do local residents and tourists perceive the problem of beach erosion and to what extent are they willing to support beach nourishment initiatives”? Results of quantitative analyses of 68 face to face survey responses of beach goers (local residents and tourists) are outlined in terms of Willingness to Donate (WTD) framework. Findings indicate: a) more than three-quarters of respondents perceived beach nourishment as an important issue, b) local residents were more willing to volunteer towards beach nourishment, and c) tourists were more willing to donate money to work towards resolving the problem. The financial and policy implications of these findings in the context of beach nourishment are discussed