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Sun Valley is located within the Blue Mountains City Council local government area, hidden in the lower Blue Mountains near Springwood.The valley is the result of a strange geological formation known as a diatreme or volcanic vent. These volcanic remains have formed a landscape that is unique in the Blue Mountains. The surrounding sandstone is dry and rugged, while very rich soils and undulating country have provided excellent native grasslands and magnificent stands of mountain blue gum trees.The first people to visit Sun Valley were the Aboriginal clans crossing, and living in, the Blue Mountains. It is possible that both Dharug and Gundungurra people used the valley.

Diaspora communities are an important source of charitable giving to their original homelands. This study explores a Muslim diaspora's motivations behind donation-giving. A two-year donation dataset of an overseas charity organisation registered in Australia was analysed. Findings show that, overall, donations are significantly related to the prevailing consumer confidence levels (r = 0.4277). However, there was also a strong, inverse correlation (r = - 0.4376) during 2020, suggesting that the plummeting consumer sentiment during COVID-19 did not impact donation revenue. As expected, during periods of religious significance (Ramadan) across both years, donations to the charity increased substantially, with the relative effect of Ramadan calculated as over 800%. This study makes a contribution by providing insights to donor behaviour through the examination of a donation dataset. This study also uses 'causal impact analysis' to calculate the effect of Ramadan on donations. Results have implications for the not-for-profit sector in Australia and other countries with Muslim diaspora communities. Limitations and suggestions for future research are also discussed.

This paper offers a new perspective on efficiency in betting markets by examining the degree to which finishing order in horseraces corresponds to probabilities inherent in odds across different categories of horserace. The application of an exploded logit procedure reveals a significantly greater degree of ordinal efficiency in higher relative to lower class races. Explanations for the phenomenon include differences in prize-related incentives, cross-market distinctions in information markets and differential opportunity/incentive for market manipulation.

Making architectural decisions in long lifecycle systems is challenging because the time between system definition and end of operations can span multiple decades, resulting in shifts in stakeholder needs and major advances in technologies. Space-based communications using relay satellite constellations is one such example, requiring substantial up-front planning to define capabilities and size capacity due to the large investment of time and resources. Additionally, there are numerous viable system architectures. In this paper, we build on existing methods to develop a graph-based decision method to assess and explore architectural flexibility in the future evolution of long lifecycle systems. The tradespace graph defines edges between similar architectures, quantifies the switching cost between architectures, using graphs to analyse the potential system evolution pathways. In a test case on NASA communication satellites, we find that hosting government communications payloads, in particular optical payloads, on commercial satellites could reduce cost and increase flexibility of the NASA network. Keywords: Space communications; communications architectures; tradespace exploration; decision-making; NASA TDRS network

© 2020 The MITRE Corporation. All Rights Reserved. Fuel selection is a strong driver of the mass fraction for many proposed lunar and Mars missions, but fuel technology trends have not been comprehensively evaluated for their impact on the system in literature. We evaluate the impact of fuel selection on overall lunar architectures. Our analysis shows that although hydrogen architectures have a higher wet mass cost, they provide more payload capacity to the lunar surface than non-hydrogen architectures given the same number of campaign launches. The Moon has been viewed as a stepping stone for future planetary exploration, so we evaluate both Mars and lunar architectures. We functionally decompose architectural decisions and compare key campaign decisions across 18 notable Mars architectural studies. The 18 landers are classified into four groups depending on which of the four the functional capabilities the lander performs, namely outbound transit, mars descent, mars ascent, and inbound transit. We find that there is no strong relationship between the Martian landers' wet mass and the length of crewed Martian surface. Furthermore, fuel type selection did not have a clear trend with the aforementioned capabilities. The lack of similarities across Mars architectures suggests the reference studies had a wide range of depths of analysis along with an array of different methods. Furthermore, they were completed at various points in history, some with high political pressure.

© 2020 The MITRE Corporation. All Rights Reserved. Fuel selection is a strong driver of the mass fraction for many proposed lunar and Mars missions, but fuel technology trends have not been comprehensively evaluated for their impact on the system in literature. We evaluate the impact of fuel selection on overall lunar architectures. Our analysis shows that although hydrogen architectures have a higher wet mass cost, they provide more payload capacity to the lunar surface than non-hydrogen architectures given the same number of campaign launches. The Moon has been viewed as a stepping stone for future planetary exploration, so we evaluate both Mars and lunar architectures. We functionally decompose architectural decisions and compare key campaign decisions across 18 notable Mars architectural studies. The 18 landers are classified into four groups depending on which of the four the functional capabilities the lander performs, namely outbound transit, mars descent, mars ascent, and inbound transit. We find that there is no strong relationship between the Martian landers' wet mass and the length of crewed Martian surface. Furthermore, fuel type selection did not have a clear trend with the aforementioned capabilities. The lack of similarities across Mars architectures suggests the reference studies had a wide range of depths of analysis along with an array of different methods. Furthermore, they were completed at various points in history, some with high political pressure.

Traditionally, government space agencies have developed aggregated systems that co-host multiple capabilities on shared spacecraft buses. However, in response to cost growth and schedule delays on past programs, leaders in the government space community have expressed an interest in disaggregation, or distributing their capabilities across multiple spacecraft. Since their aggregated National Polar-orbiting Operational Satellite System (NPOESS) program was cancelled in 2010, both the National Oceanic and Atmospheric Administration (NOAA) and the Department of Defense (DoD) have investigated opportunities to reduce program costs through disaggregation. This paper expands their initial investigation and explores the cost impacts of aggregation and disaggregation across a large trade space of candidate architectures for environmental monitoring in low-Earth orbit. We find that on average, aggregated architectures are less costly than fully disaggregated ones but also find opportunities for cost savings by developing semi-aggregated systems, or systems with one or two satellites per orbital plane. Finally, we investigate several trades that are currently under consideration by NOAA and the DoD and make recommendations for future environmental monitoring systems in low-Earth orbit. ; Massachusetts Institute of Technology (Sandia Corporation Excellence in Engineering Graduate Fellowship) ; Skolkovo Institute of Science and Technology