247 resultados para 116-718
Resumo:
Recent literature has argued that environmental efficiency (EE), which is built on the materials balance (MB) principle, is more suitable than other EE measures in situations where the law of mass conversation regulates production processes. In addition, the MB-based EE method is particularly useful in analysing possible trade-offs between cost and environmental performance. Identifying determinants of MB-based EE can provide useful information to decision makers but there are very few empirical investigations into this issue. This article proposes the use of data envelopment analysis and stochastic frontier analysis techniques to analyse variation in MB-based EE. Specifically, the article develops a stochastic nutrient frontier and nutrient inefficiency model to analyse determinants of MB-based EE. The empirical study applies both techniques to investigate MB-based EE of 96 rice farms in South Korea. The size of land, fertiliser consumption intensity, cost allocative efficiency, and the share of owned land out of total land are found to be correlated with MB-based EE. The results confirm the presence of a trade-off between MB-based EE and cost allocative efficiency and this finding, favouring policy interventions to help farms simultaneously achieve cost efficiency and MP-based EE.
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The influence of different electrolyte cations ((Li+, Na+, Mg2+, tetrabutyl ammonium (TBA+)) on the TiO2 conduction band energy (Ec) the effective electron lifetime (τn), and the effective electron diffusion coefficient (Dn) in dye-sensitized solar cells (DSCs) was studied quantitatively. The separation between Ec and the redox Fermi level, EF,redox, was found to decrease as the charge/radius ratio of the cations increased. Ec in the Mg2+ electrolyte was found to be 170 meV lower than that in the Na+ electrolyte and 400 meV lower than that in the TBA+ electrolyte. Comparison of Dn and τn in the different electrolytes was carried out by using the trapped electron concentration as a measure of the energy difference between Ec and the quasi-Fermi level, nEF, under different illumination levels. Plots of Dn as a function of the trapped electron density, nt, were found to be relatively insensitive to the electrolyte cation, indicating that the density and energetic distribution of electron traps in TiO2 are similar in all of the electrolytes studied. By contrast, plots of τn versus nt for the different cations showed that the rate of electron back reaction is more than an order of magnitude faster in the TBA+ electrolyte compared with the Na+ and Li+ electrolytes. The electron diffusion lengths in the different electrolytes followed the sequence of Na+ > Li+ > Mg2+ > TBA+. The trends observed in the AM 1.5 current–voltage characteristics of the DSCs are rationalized on the basis of the conduction band shifts and changes in electron lifetime.
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Background: When experiencing sleep problems for the first time, consumers may often approach community pharmacists for advice as they are easily accessible health care professionals in the community. In Australian community pharmacies there are no specific tools available for use by pharmacists to assist with the assessment and handling of consumers with sleep enquiries. Objective: To assess the feasibility of improving the detection of sleep disorders within the community through the pilot of a newly developed Community Pharmacy Sleep Assessment Tool (COP-SAT). Method: The COP-SAT was designed to incorporate elements from a number of existing, standardized, and validated clinical screening measures. The COP-SAT was trialed in four Australian community pharmacies over a 4-week period. Key findings: A total of 241 community pharmacy consumers were assessed using the COP-SAT. A total of 74 (30.7%) were assessed as being at risk of insomnia, 26 (10.7%) were at risk of daytime sleepiness, 19 (7.9%) were at risk of obstructive sleep apnea, and 121 (50.2%) were regular snorers. A total of 116 (48.1%) participants indicated that they consume caffeine before bedtime, of which 55 (47%) had associated symptoms of sleep onset insomnia. Moreover, 85 (35%) consumed alcohol before bedtime, of which 50 (58%) experienced fragmented sleep, 50 (58%) were regular snorers, and nine (10.6%) had apnea symptoms. The COP-SAT was feasible in the community pharmacy setting. The prevalence of sleep disorders in the sampled population was high, but generally consistent with previous studies on the general population. Conclusion: A large proportion of participants reported sleep disorder symptoms, and a link was found between the consumption of alcohol and caffeine substances at bedtime and associated symptoms. While larger studies are needed to assess the clinical properties of the tool, the results of this feasibility study have demonstrated that the COP-SAT may be a practical tool for the identification of patients at risk of developing sleep disorders in the community.
Resumo:
Purpose – The purpose of this study is to examine the associations between attitudes to academic achievement and post university success using perceptions of attractiveness, gender, ethnic identity, personality, and social acceptance as antecedents. Design/methodology/approach – An online questionnaire was completed by male (N=116) and female (N=126) university students from various cultural backgrounds. To evaluate the proposed relationships, multiple regression analysis was used. Findings – The findings suggest that attractiveness is related to attitudes to academic achievement and success through its association with social appeal and acceptance. Ethnic identity is also related to both academic achievement and post university success. Personality is not positively related to academic achievement. Finally, social acceptance is positively related to academic achievement for males and to success for females. Research limitations/implications – Whilst the survey targeted students from various cultural backgrounds studying in Australia, it did not look at university students from other countries. A cross-cultural perspective could reveal further differences in attitudes. Originality/value – This study links attractiveness and academic achievement theories. The findings have implications for tertiary institutions and suggest academics and policy-makers to vigorously promote core personality and values such as intelligence, communication skills, and sincerity, rather than allow superficial values such as attractiveness to be placed at the centre stage of students' endeavour.
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Big data is big news in almost every sector including crisis communication. However, not everyone has access to big data and even if we have access to big data, we often do not have necessary tools to analyze and cross reference such a large data set. Therefore this paper looks at patterns in small data sets that we have ability to collect with our current tools to understand if we can find actionable information from what we already have. We have analyzed 164390 tweets collected during 2011 earthquake to find out what type of location specific information people mention in their tweet and when do they talk about that. Based on our analysis we find that even a small data set that has far less data than a big data set can be useful to find priority disaster specific areas quickly.
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Norms regulate the behaviour of their subjects and define what is legal and what is illegal. Norms typically describe the conditions under which they are applicable and the normative effects as a results of their applications. On the other hand, process models specify how a business operation or service is to be carried out to achieve a desired outcome. Norms can have significant impact on how business operations are conducted and they can apply to the whole or part of a business process. For example, they may impose conditions on the different aspects of a process (e.g., perform tasks in a specific sequence (control-flow), at a specific time or within a certain time frame (temporal aspect), by specific people (resources)). We propose a framework that provides the formal semantics of the normative requirements for determining whether a business process complies with a normative document (where a normative document can be understood in a very broad sense, ranging from internal policies to best practice policies, to statutory acts). We also present a classification of normal requirements based on the notion of different types of obligations and the effects of violating these obligations.
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Increasing awareness of the benefits of stimulating entrepreneurial behaviour in small and medium enterprises has fostered strong interest in innovation programs. Recently many western countries have invested in design innovation for better firm performance. This research presents some early findings from a study of companies that participated in a holistic approach to design innovation, where the outcomes include better business performance and better market positioning in global markets. Preliminary findings from in-depth semi-structured interviews indicate the importance of firm openness to new ways of working and to developing new processes of strategic entrepreneurship. Implications for theory and practice are discussed.
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THE UVI working group acknowledges the contribution of Vitamin D to bone health as stated in our paper. However, we concluded that an optimal level of Vitamin D for humans has not yet been established with any certainty...
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ZIF-8 thin layer has been synthesized on the asymmetric porous polyethersulfone (PES) substrate via secondary seeded growth. Continuous and dense ZIF-8 layer, containing microcavities, has good affinity with the PES support. Single gas permeance was measured for H2, N2, CH4, O2, and Ar at different pressure gradients and temperatures. Molecular sieving separation has been achieved for selectively separating hydrogen from larger gases. At 333 K, the H2 permeance can reach ∼4 × 10−7 mol m−2 s−1 Pa−1, and the ideal separation factors of H2 from Ar, O2, N2, and CH4 are 9.7, 10.8, 9.9, and 10.7, respectively. Long-term hydrogen permeance and H2/N2 separation performance show the stable permeability of the derived membranes.
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We propose a new route to hydrogen isotope separation which exploits the quantum sieving effect in the context of transmission through asymmetrically decorated, doped porous graphenes. Selectivities of D2 over H2 as well as rate constants are calculated based on ab initio interaction potentials for passage through pure and nitrogen functionalized porous graphene. One-sided dressing of the membrane with metal provides the critical asymmetry needed for an energetically favorable pathway.
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As new diseases and medical conditions emerge, new community groups appear in the public health arena as consumer advocates or lobby groups seeking to affect policy or to represent ‘communities’ formed around these new diseases and conditions. The role of these groups in public health, their political status, and the extent to which they are actually representative are highly problematic for public health. These new constellations of social groups and activities challenge traditional ideas about public health decision-making and demand a rethinking of the constituency and limits of public health. Using discourse theory, symbolic interactionism, and ethological theory, the authors examine one case, exploring the perspectives of various communities on hepatitis C, and explore some issues that this raises for public health.
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Urban agriculture plays an important role in many facets of food security, health and sustainability. The city farm is one such manifestation of urban agriculture: it functions as a location centric social hub that supplies food, education, and opportunities for strengthening the diverse sociocultural fabrics of the local community. This paper presents the case of Northey Street City Farm in Brisbane, Australia as an opportunity space for design. The paper iden-tifies four areas that present key challenges and opportunities for HCI design that support social sustainability of the city farm: A preference for face-to-face contact leads to inconsistencies in shared knowledge; a dependence on volun-teers and very limited resources necessitates easily accessible interventions; other local urban agricultural activity needing greater visibility; and the vulner-ability of the physical location to natural phenomenon, in this instance flooding, present a design challenge and a need to consider disaster management.
Resumo:
Purpose – The question of whether female-owned firms underperform male-owned firms has triggered much research and discussion. Klapper and Parker's review concluded that the majority of prior research suggests that female-owned firms underperform relative to male-owned firms. However, using performance measures that control for size and risk (and after controlling for demographic differences such as industry, experience and hours worked) Robb and Watson found no gender performance difference in their sample of newly established US firms. The aim of this study, therefore, is to replicate Robb and Watson's study to determine whether their findings can be generalized to another geographical location, Australia. Design/methodology/approach – The authors test the female underperformance hypothesis using data from the CAUSEE project, a panel study which follows young firms over four years. They use three outcome variables: survival rates, return on assets and the Sharpe ratio. Findings – Consistent with Robb and Watson the results indicate that female-owned firms do not underperform male-owned firms. Originality/value – While replication studies are rare in entrepreneurship, they are an important tool for accumulating generalizable knowledge. The results suggest that while female-owned firms differ from male-owned firms in terms of many control variables (such as industry, owners' previous experience and hours worked) they are no less successful. This outcome should help dispel the female underperformance myth; which if left unchallenged could result in inappropriate policy decisions and, more importantly, could discourage women from establishing new ventures.
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We put forward a new experimental economics design with monetary incentives to estimate students’ perceptions of grading discrimination. We use this design in a large field experiment which involved 1,200 British students in grade 8 classrooms across 29 schools. In this design, students are given an endowment they can invest on a task where payoff depends on performance. The task is a written verbal test which is graded non anonymously by their teacher, in a random half of the classrooms, and graded anonymously by an external examiner in the other random half of the classrooms. We find significant evidence that students’ choices reflect perceptions of biases in teachers’ grading practices. Our results show systematic gender interaction effects: male students invest less with female teachers than with male teachers while female students invest more with male teachers than with female teachers. Interestingly, female students’ perceptions are not in line with actual discrimination: Teachers tend to give better grades to students of their own gender. Results do not suggest that ethnicity and socioeconomic status play a role. .
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This paper documents a preliminary investigation into the relationship between neurodiversity and the built environment using a pilot project developed with Logan City Council and engaging candidates within the Master of Urban Design at the Queensland University of Technology. The research begins to examine the way many places are designed and built can be alienating and inhibit accessibility to people with movement and sensory differences. Logan Central has been used as a case study area to map the physical attributes, and identify barriers and challenges in the built environment – specifically for people with disabilities but also taking in consideration the wider population. The integration of all individuals – mainstream, those with disability, differences and multigenerational populations – strengthens the social and economic fabric of Australia, enabling its citizens to live healthy, productive, and fulfilling lives.