873 resultados para Net expected return
Resumo:
This work presents a demand side response model (DSR) which assists small electricity consumers, through an aggregator, exposed to the market price to proactively mitigate price and peak impact on the electrical system. The proposed model allows consumers to manage air-conditioning when as a function of possible price spikes. The main contribution of this research is to demonstrate how consumers can minimise the total expected cost by optimising air-conditioning to account for occurrences of a price spike in the electricity market. This model investigates how pre-cooling method can be used to minimise energy costs when there is a substantial risk of an electricity price spike. The model was tested with Queensland electricity market data from the Australian Energy Market Operator and Brisbane temperature data from the Bureau of Statistics during hot days on weekdays in the period 2011 to 2012.
Resumo:
Throughout a long and occasionally distinguished career first as a television sports correspondent, then chat show host (dramatically ended by the accidental homicide of a guest live on air), then rebirth as a radio presenter at North Norfolk Digital, Alan Partridge has navigated the stormy waters of the British media landscape, now achieving mainstream success on the big screen with a starring role in Steve Coogan’s Alpha Papa (Declan Lowney, 2013). A man who in his desperation for a television series of his own once sank so low as to pitch a show called Monkey Tennis to the BBC finally finds his inner hero in a film which, while presenting mainly as comedy, also contains a biting critique of trends in the British media with which all journalists and media practitioners in general will be familiar. Alpha Papa is a nostalgic, elegiac riff on the pleasures and values of local radio the way it used to be, exemplified by North Norfolk Digital’s stable of flawed, but endearing jocks – Wally Banter, Bruno Brooks, Dave Clifton (who in one scene recounts the depths to which he sank as an alcoholic, drug addicted wreck—“I woke up in a skip with someone else’s underpants in my mouth. I can laugh about it now …”), and Pat Farrell. 50- something Pat is sacked by the new owners of North Norfolk Digital, who in their efforts to transform the station into a “multiplatform content provider” going by the more Gen Yfriendly name of Shape (“the way you want it to be”), wish to replace him with a younger, brattish model lacking in taste and manners. Out go records by the likes of Glen Campbell and Neil Diamond (“You can keep Jesus Christ”, observes Partridge after playing Diamond’s Sweet Caroline in a demonstration of the crackling radio repartee for which he is by now renowned, “that was the king of the Jews”), in comes Roachford. Pat, grieving his dead wife Molly, finally snaps and turns the glitzy media launch of Shape into a hostage siege. Only Alan Partridge, it seems, can step in and talk Pat out of a looming catastrophe.
Resumo:
In this paper we define two models of users that require diversity in search results; these models are theoretically grounded in the notion of intrinsic and extrinsic diversity. We then examine Intent-Aware Expected Reciprocal Rank (ERR-IA), one of the official measures used to assess diversity in TREC 2011-12, with respect to the proposed user models. By analyzing ranking preferences as expressed by the user models and those estimated by ERR-IA, we investigate whether ERR-IA assesses document rankings according to the requirements of the diversity retrieval task expressed by the two models. Empirical results demonstrate that ERR-IA neglects query-intents coverage by attributing excessive importance to redundant relevant documents. ERR-IA behavior is contrary to the user models that require measures to first assess diversity through the coverage of intents, and then assess the redundancy of relevant intents. Furthermore, diversity should be considered separately from document relevance and the documents positions in the ranking.
Resumo:
Providing mobility corridors for communities, enabling freight networks to transport goods and services, and a pathway for emergency services and disaster relief operations, roads are a vital component of our societal system. In the coming decades, a number of modern issues will face road agencies as a result of climate change, resource scarcity and energy related challenges that will have implications for society. To date, these issues have been discussed on a case by case basis, leading to a fragmented approach by state and federal agencies in considering the future of roads – with potentially significant cost and risk implications. Within this context, this paper summarises part of a research project undertaken within the ‘Greening the Built Environment’ program of the Sustainable Built Environment National Research Centre (SBEnrc, Australia), which identified key factors or ‘trends’ affecting the future of roads and key strategies to ensure that road agencies can continue to deliver road infrastructure that meets societal needs in an environmentally appropriate manner. The research was conducted over two years, including a review of academic and state agency literature, four stakeholder workshops in Western Australia and Queensland, and industry consultation. The project was supported financially and through peer review and contribution, by Main Roads Western Australia, QLD Department of Transport and Main Roads, Parsons Brinckerhoff, John Holland Group, and the Australian Green Infrastructure Council (AGIC). The project highlighted several potential trends that are expected to affect road agencies in the future, including predicted resource and materials shortages, increases in energy and natural resources prices, increased costs related to greenhouse gas emissions, changing use and expectations of roads, and changes in the frequency and intensity of weather events. Exploring the implications of these potential futures, the study then developed a number of strategies in order to prepare transport agencies for the associated risks that such trends may present. An unintended outcome of the project was the development of a process for enquiring into future scenarios, which will be explored further in Stage 2 of the project (2013-2014). The study concluded that regardless of the type and scale of response by the agency, strategies must be holistic in approach, and remain dynamic and flexible.
Resumo:
Convective downburst wind storms generate the peak annual gust wind speed for many parts of the non-cyclonic world at return periods of importance for ultimate limit state design. Despite this there is little clear understanding of how to appropriately design for these wind events given their significant dissimilarities to boundary layer winds upon which most design is based. To enhance the understanding of wind fields associated with these storms a three-dimensional numerical model was developed to simulate a multitude of idealised downburst scenarios and to investigate their near-ground wind characteristics. Stationary and translating downdraft wind events in still and sheared environments were simulated with baseline results showing good agreement with previous numerical work and full-scale observational data. Significant differences are shown in the normalised peak wind speed velocity profiles depending on the environmental wind conditions in the vicinity of the simulated event. When integrated over the height of mid- to high rise structures, all simulated profiles are shown to produce wind loads smaller than an equivalent 10 m height matched open terrain boundary layer profile. This suggests that for these structures the current design approach is conservative from an ultimate loading standpoint. Investigating the influence of topography on the structure of the simulated near-ground downburst wind fields, it is shown that these features amplify wind speeds in a manner similar to that expected for boundary layer winds, but the extent of amplification is reduced. The level of reduction is shown to be dependent on the depth of the simulated downburst outflow.
Resumo:
Capacity reduction programmes, in the form of buybacks or decommissioning, have had relatively widespread application in fisheries in the US, Europe and Australia. A common criticism of such programmes is that they remove the least efficient vessels first, resulting in an increase in average efficiency of the remaining fleet, which tends to increase the effective fishing power of the remaining fleet. In this paper, the effects of a buyback programme on average technical efficiency in Australia’s Northern Prawn Fishery are examined using a multi-output production function approach with an explicit inefficiency model. As expected, the results indicate that average efficiency of the remaining vessels was generally greater than that of the removed vessels. Further, there was some evidence of an increase in average scale efficiency in the fleet as the remaining vessels were closer, on average, to the optimal scale. Key factors affecting technical efficiency included company structure and the number of vessels fishing. In regard to fleet size, our model suggests positive externalities associated with more boats fishing at any point in time (due to information sharing and reduced search costs), but also negative externalities due to crowding, with the latter effect dominating the former. Hence, the buyback resulted in a net increase in the individual efficiency of the remaining vessels due to reduced crowding, as well as raising average efficiency through removal of less efficient vessels.
Resumo:
Background
With dwindling malaria cases in Bhutan in recent years, the government of Bhutan has made plans for malaria elimination by 2016. This study aimed to determine coverage, use and ownership of LLINs, as well as the prevalence of asymptomatic malaria at a single time-point, in four sub-districts of Bhutan.
Methods
A cross-sectional study was carried out in August 2013. Structured questionnaires were administered to a single respondent in each household (HH) in four sub-districts. Four members from 25 HH, randomly selected from each sub-district, were tested using rapid diagnostic tests (RDT) for asymptomatic Plasmodium falciparum and Plasmodium vivax infection. Multivariable logistic regression models were used to identify factors associated with LLIN use and maintenance.
Results
All blood samples from 380 participants tested negative for Plasmodium infections. A total of 1,223 HH (92.5% of total HH) were surveyed for LLIN coverage and use. Coverage of LLINs was 99.0% (1,203/1,223 HH). Factors associated with decreased odds of sleeping under a LLIN included: washing LLINs
Resumo:
BACKGROUND: Within Australia and internationally (Health Workforce Australia, 2012) an increasing and on-going nursing workforce shortage is documented. Recent international estimates indicate that there will be ongoing and significant gaps in the supply of a nursing workforce; the United Kingdom is predicted to have a reduction of 12.12% nurses over the coming eight years if a current 'steady state' is maintained (Buchan and Seacombe, 2011); Canada is predicted to have a shortage of 60,000 nurses by 2022 (Tomblin et al., 2012) with Australia's anticipated nursing shortage reported as over 90,000 by the year 2025 (Health Workforce Australia, 2012). Queensland Health in response to their tracked emerging nursing and midwifery workforce shortages developed a nursing and midwifery refresher programme to return registered staff back to the workforce. A study was undertaken between 2008 and 2010 to provide an understanding of how non-practising nurses and midwives maybe supported back into the workforce. METHODS: Programme applicants (444) were invited to respond to an on-line survey designed to understand what aspects of the programme supported their learning and ability to return to the workforce. This number represents those who applied but not all completed or commenced the programme. Descriptive statistics (Polit and Beck, 2008) were used to collate quantifiable survey responses and free text and unsolicited responses were themed. RESULTS: The survey received a 35.5% response rate (n=158) with a return of 20% of unsolicited comments in the form of e-mail responses which were included in the themed results. Key themes supporting participants' learning and ability to return to the workforce were: Respondents were 94% female and 6% male, with 37.7% >51 years of age. Child rearing was the foremost reason for female staff relinquishing workforce roles (36.6%). The primary reason for returning to the workforce was maintenance of registration (40.5%). Both theory and clinical placement components were seen by participants as contributing to their confidence to return to the health workforce. CONCLUSION: The Queensland Nursing and Midwifery Refresher Programs provided a structured programme for registered, non-practising nurses and midwives to return to the Queensland Health workforce. Responses indicated that clinical supervision and contract learning should be central to a return to workforce induction programme for registered but non-practising nurses and midwives. The majority of nurses and midwives returning to the workforce were approaching retirement age in 10-15 years.
Resumo:
The global grown in institutional investors means that firms can no longer ignore their influence in capital markets. However, not all institutional investors have the same motives to influence the firms they invest in. Institution investors' ability to influence management depends on the size of their investment and whether they have any business relations with the firm. Using a sample of Australian firms from 2006 to 2008, our empirical results show that the proportion of a company's shares held by institutional investors is positively associated with firm governance ratings, risk and profitability. This study shows that a positive association between risk and return is associated with large active institutional ownership, which we interpret as shareholders with sufficient power to pressure management to increase short-term profits.
Resumo:
We propose expected attainable discrimination (EAD) as a measure to select discrete valued features for reliable discrimination between two classes of data. EAD is an average of the area under the ROC curves obtained when a simple histogram probability density model is trained and tested on many random partitions of a data set. EAD can be incorporated into various stepwise search methods to determine promising subsets of features, particularly when misclassification costs are difficult or impossible to specify. Experimental application to the problem of risk prediction in pregnancy is described.
Resumo:
Flexible design practices broadly permit that design values outside the normal range can be accepted as appropriate for a site-specific context providing that the risk is evaluated and is tolerable. Execution of flexible design demands some evaluation of risk. In restoration projects, it may be the case that an immovable object exists within the zone of the expected deflection of a road safety barrier system. Only by design exception can the situation be determined to be acceptable. However, the notion of using flexible design for road safety barrier design is not well developed. The existence of a diminishing return relationship between safety benefits and provision of increased clear zone has been established previously. This paper proposes that a similar rationale might reasonably apply for the deflection zone behind road safety barriers and describes how the risk associated with road safety barriers might be quantified in order that defensible road safety barrier design can exist below the lower bounds of normal design standards. As such, the methodology described in this paper may provide some basis to enable road authorities to make informed design decisions, particularly for restoration, or “Brownfield”, projects.