Optimization of Complex Water Supply Network

AbstractThe Millennium drought created critical water shortages throughout Australia and particularly in South East Queensland (SEQ). In response to this the bulk water network was significantly enhanced resulting in large infrastructure augmentations consisting of cross regional pipelines, a desalination plant and a purified recycled water plant. Given that SEQ can transition from drought to flood and vice versa in a short period of time it is a fine balance to operate the new more complicated asset base economically whilst maintaining sufficient supply security. With rising energy prices and the increasing cost of living pressures, there is an immediate need to better understand what optimal grid operation looks like and this is currently being investigated by the Seqwater Decision Support System (DSS).Till now, a network such as the SEQ water grid with its variety of water supply sources of varying reliabilities and complexity of the network has been operated in a relatively manual manner using manual heuristics. Given the number of factors which need to be considered when making decisions about which parts of the network to activate at any one time and the limitations of the human mind to resolve these, means that sub optimal results are frequently generated.The development of a DSS using optimization techniques can help determine the most efficient mode of delivery of water taking into account the operating costs of the various assets within the network, amongst a range of other constraints. This paper goes into detail the application of the optimization technology to the SEQ Water grid

Cluster spacecraft observations of a ULF wave enhanced by Space Plasma Exploration by Active Radar (SPEAR)

Space Plasma Exploration by Active Radar (SPEAR) is a high-latitude ionospheric heating facility capable of exciting ULF waves on local magnetic field lines. We examine an interval from 1 February 2006 when SPEAR was transmitting a 1 Hz modulation signal with a 10 min on-off cycle. Ground magnetometer data indicated that SPEAR modulated currents in the local ionosphere at 1 Hz, and enhanced a natural field line resonance with a 10 min period. During this interval the Cluster spacecraft passed over the heater site. Signatures of the SPEAR-enhanced field line resonance were present in the magnetic field data measured by the magnetometer on-board Cluster-2. These are the first joint ground- and space-based detections of field line tagging by SPEAR

The interaction between transpolar arcs and cusp spots

Transpolar arcs and cusp spots are both auroral phenomena which occur when the interplanetary magnetic field is northward. Transpolar arcs are associated with magnetic reconnection in the magnetotail, which closes magnetic flux and results in a “wedge” of closed flux which remains trapped, embedded in the magnetotail lobe. The cusp spot is an indicator of lobe reconnection at the high-latitude magnetopause; in its simplest case, lobe reconnection redistributes open flux without resulting in any net change in the open flux content of the magnetosphere. We present observations of the two phenomena interacting—i.e., a transpolar arc intersecting a cusp spot during part of its lifetime. The significance of this observation is that lobe reconnection can have the effect of opening closed magnetotail flux. We argue that such events should not be rare

Eliciting conditioned taste aversion in lizards: Live toxic prey are more effective than scent and taste cues alone

© 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd Conditioned taste aversion (CTA) is an adaptive learning mechanism whereby a consumer associates the taste of a certain food with symptoms caused by a toxic substance, and thereafter avoids eating that type of food. Recently, wildlife researchers have employed CTA to discourage native fauna from ingesting toxic cane toads (Rhinella marina), a species that is invading tropical Australia. In this paper, we compare the results of 2 sets of CTA trials on large varanid lizards (“goannas,” Varanus panoptes). One set of trials (described in this paper) exposed recently-captured lizards to sausages made from cane toad flesh, laced with a nausea-inducing chemical (lithium chloride) to reinforce the aversion response. The other trials (in a recently-published paper, reviewed herein) exposed free-ranging lizards to live juvenile cane toads. The effectiveness of the training was judged by how long a lizard survived in the wild before it was killed (fatally poisoned) by a cane toad. Both stimuli elicited rapid aversion to live toads, but the CTA response did not enhance survival rates of the sausage-trained goannas after they were released into the wild. In contrast, the goannas exposed to live juvenile toads exhibited higher long-term survival rates than did untrained conspecifics. Our results suggest that although it is relatively easy to elicit short-term aversion to toad cues in goannas, a biologically realistic stimulus (live toads, encountered by free-ranging predators) is most effective at buffering these reptiles from the impact of invasive toxic prey

The interaction between transpolar arcs and cusp spots

Transpolar arcs and cusp spots are both auroral phenomena which occur when the interplanetary magnetic field is northward. Transpolar arcs are associated with magnetic reconnection in the magnetotail, which closes magnetic flux and results in a "wedge" of closed flux which remains trapped, embedded in the magnetotail lobe. The cusp spot is an indicator of lobe reconnection at the high-latitude magnetopause; in its simplest case, lobe reconnection redistributes open flux without resulting in any net change in the open flux content of the magnetosphere. We present observations of the two phenomena interacting--i.e., a transpolar arc intersecting a cusp spot during part of its lifetime. The significance of this observation is that lobe reconnection can have the effect of opening closed magnetotail flux. We argue that such events should not be rare

COVID-19 and Ventilation in the Home; Investigating Peoples’ Perceptions and Self-Reported Behaviour (the COVID-19 Rapid Survey of Adherence to Interventions and Responses [CORSAIR] Study)

Ventilating indoor spaces helps prevent COVID-19 transmission. We investigated self-reported rates of opening windows to improve ventilation in the home, perceived effectiveness of opening windows, and confidence that if you wanted to, you could open windows. One in 6 people reported rarely, if ever, opening windows in their home in the last week. Three in 4 people knew that opening windows to improve ventilation was an effective way to prevent the spread of COVID-19 and 5 in 6 were confident that they could open windows in their home. Official messaging should continue to seek to improve knowledge about the effectiveness of ventilation for reducing COVID-19 transmission, and increase the frequency of window opening

Factors associated with nonessential workplace attendance during the Covid-19 pandemic in the UK in early 2021: evidence from cross-sectional surveys

Objectives: Working from home where possible is important in reducing spread of Covid-19. In early 2021, a quarter of people in England who believed they could work entirely from home reported attending their workplace. To inform interventions to reduce this, this study examined associated factors. Study design: Data from the ongoing CORSAIR survey series of nationally representative samples of people in the UK aged 16+ years in January-February 2021 were used. Methods The study sample was 1422 respondents who reported that they could work completely from home. The outcome measure was self-reported workplace attendance at least once during the preceding week. Factors of interest were analysed in three blocks: 1) sociodemographic variables, 2) variables relating to respondents’ circumstances, and 3) psychological variables. Results 26.8% (95%CI=24.5%-29.1%) of respondents reported having attended their workplace at least once in the preceding week. Sociodemographic variables and living circumstances significantly independently predicted non-essential workplace attendance: male gender (OR=1.85,95%CI=1.33-2.58), dependent children in the household (OR=1.65,95%CI=1.17-2.32), financial hardship (OR=1.14,95%CI=1.08-1.21), socio-economic grade C2DE (OR=1.74, 95%CI=1.19-2.53), working in sectors such as health or social care (OR=4.18, 95%CI=2.56-6.81), education and childcare (OR=2.45, 95%CI=1.45-4.14) and key public service (OR=3.78, 95%CI=1.83-7.81), and having been vaccinated (OR=2.08,95%CI=1.33-3.24). Conclusions Non-essential workplace attendance in the UK in early 2021 during the Covid-19 pandemic was significantly independently associated with a range of sociodemographic variables and personal circumstances. Having been vaccinated, financial hardship, socio-economic grade C2DE, having a dependent child at home, working in certain key sectors were associated with higher likelihood of workplace attendance

Do members of the public think they should use lateral flow tests or PCR tests when they have COVID-19-like symptoms? The COVID-19 Rapid Survey of Adherence to Interventions and Responses [CORSAIR] study

OBJECTIVES: To investigate public use of lateral flow test [LFT] or polymerase chain reaction [PCR] test when experiencing key COVID-19 symptoms. STUDY DESIGN: Two waves of a cross-sectional nationally representative online survey (data collected 1-2 June and 14-15 June 2021; n=3665 adults aged 18 years or over living in England or Scotland). METHODS: We report data investigating which type of test, if any, the public think Government guidance asks people to use if they have COVID-19 symptoms. In people with key COVID-19 symptoms (high temperature, cough, loss of sense of taste or smell), we also describe uptake of testing, if any. RESULTS: 10% of respondents thought Government guidance stated that they should take an LFT if symptomatic, while 18% of people thought that should take a PCR test; 60% thought they should take both types of test (12% did not select either option). In people who were symptomatic, 32% reported taking a test to confirm whether they had COVID-19. Of these, 53% reported taking a PCR test and 44% reported taking an LFT. CONCLUSIONS: Despite Government guidance stating that anyone with key COVID-19 symptoms should complete a PCR test, a significant percentage of the population use LFT tests when symptomatic. Communications should emphasise the superiority of, and need for, PCR tests in people with symptoms

Holding a stigmatizing attitude at the start of the COVID-19 outbreak: A cross-sectional survey

OBJECTIVES: To identify the prevalence of a stigmatizing attitude towards people of Chinese origin at the start of the COVID-19 outbreak in the UK population and investigate factors associated with holding the stigmatizing attitude. DESIGN: Online cross-sectional survey conducted 10-13 February 2020 (n = 2006, people aged 16 years or over and living in the UK). METHODS: We asked participants to what extent they agreed it was best to avoid areas heavily populated by Chinese people because of the COVID-19 outbreak. Survey materials also asked about: worry, perceived risk, knowledge, information receipt, perception of government response to COVID-19, and personal characteristics. We ran binary logistic regressions to investigate associations between holding a stigmatizing attitude, personal characteristics, and psychological and contextual factors. RESULTS: 26.1% people (95% CI 24.2-28.0%, n = 524/2006) agreed it was best to avoid areas heavily populated by Chinese people. Holding a stigmatizing attitude was associated with greater worry about COVID-19, greater perceived risk of COVID-19, and poorer knowledge about COVID-19. CONCLUSIONS: At the start of the COVID-19 pandemic, a large percentage of the UK public endorsed avoiding areas in the UK heavily populated by people of Chinese origin. This attitude was associated with greater worry about, and perceived risk of, the COVID-19 outbreak as well as poorer knowledge about COVID-19. At the start of future novel infectious disease outbreaks, proactive communications from official sources should provide context and facts to reduce uncertainty and challenge stigmatizing attitudes, to minimize harms to affected communities