Dénombrement dans les empilements apolloniens généralisés et distribution angulaire dans les extensions quadratiques imaginaires.

Cette thèse traite de deux thèmes principaux. Le premier concerne l'étude des empilements apolloniens généralisés de cercles et de sphères. Généralisations des classiques empilements apolloniens, dont l'étude remonte à la Grèce antique, ces objets s'imposent comme particulièrement attractifs en théorie des nombres. Dans cette thèse sera étudié l'ensemble des courbures (les inverses des rayons) des cercles ou sphères de tels empilements. Sous de bonnes conditions, ces courbures s'avèrent être toutes entières. Nous montrerons qu'elles vérifient un principe local-global partiel, nous compterons le nombre de cercles de courbures plus petites qu'une quantité donnée et nous nous intéresserons également à l'étude des courbures premières. Le second thème a trait à la distribution angulaire des idéaux (ou plutôt ici des nombres idéaux) des corps de nombres quadratiques imaginaires (que l'on peut voir comme la distribution des points à coordonnées entières sur des ellipses). Nous montrerons que la discrépance de l'ensemble des angles des nombres idéaux entiers de norme donnée est faible et nous nous intéresserons également au problème des écarts bornés entre les premiers d'extensions quadratiques imaginaires dans des secteurs.

Unconformity-bounded stratigraphic units (UBSUs) in an italian alluvial-plain area: recognizing and dating

We studied the coastal zone of the Tavoliere di Puglia plain, (Puglia region, southern Italy) with the aim to recognize the main unconformities, and therefore, the unconformity-bounded stratigraphic units (UBSUs; Salvador 1987, 1994) forming its Quaternary sedimentary fill. Recognizing unconformities is particularly problematic in an alluvial plain, due to the difficulties in distinguishing the unconformities that bound the UBSUs. So far, the recognition of UBSUs in buried successions has been made mostly by using seismic profiles. Instead, in our case, the unavailability of the latter has prompted us to address the problem by developing a methodological protocol consisting of the following steps: I) geological survey in the field; II) draft of a preliminary geological setting based on the field-survey results; III) dating of 102 samples coming from a large number of boreholes and some outcropping sections by means of the amino acid racemization (AAR) method applied to ostracod shells and 14C dating, filtering of the ages and the selection of valid ages; IV) correction of the preliminary geological setting in the light of the numerical ages; definition of the final geological setting with UBSUs; identification of a ‘‘hypothetical’’ or ‘‘attributed time range’’ (HTR or ATR) for each UBSU, the former very wide and subject to a subsequent modification, the latter definitive; V) cross-checking between the numerical ages and/or other characteristics of the sedimentary bodies and/or the sea-level curves (with their effects on the sedimentary processes) in order to restrict also the hypothetical time ranges in the attributed time ranges. The successful application of AAR geochronology to ostracod shells relies on the fact that the ability of ostracods to colonize almost all environments constitutes a tool for correlation, and also allow the inclusion in the same unit of coeval sediments that differ lithologically and paleoenvironmentally. The treatment of the numerical ages obtained using the AAR method required special attention. The first filtering step was made by the laboratory (rejection criteria a and b). Then, the second filtering step was made by testing in the field the remaining ages. Among these, in fact, we never compared an age with a single preceding and/or following age; instead, we identified homogeneous groups of numerical ages consistent with their reciprocal stratigraphic position. This operation led to the rejection of further numerical ages that deviate erratically from a larger, homogeneous age population which fits well with its stratigraphic position (rejection criterion c). After all of the filtering steps, the valid ages that remained were used for the subdivision of the sedimentary sequences into UBSUs together with the lithological and paleoenvironmental criteria. The numerical ages allowed us, in the first instance, to recognize all of the age gaps between two consecutive samples. Next, we identified the level, in the sedimentary thickness that is between these two samples, that may represent the most suitable UBSU boundary based on its lithology and/or the paleoenvironment. The recognized units are: I) Coppa Nevigata sands (NEA), HTR: MIS 20–14, ATR: MIS 17–16; II) Argille subappennine (ASP), HTR: MIS 15–11, ATR: MIS 15–13; III) Coppa Nevigata synthem (NVI), HTR: MIS 13–8, ATR: MIS 12–11; IV) Sabbie di Torre Quarto (STQ), HTR: MIS 13–9.1, ATR: MIS 11; V) Amendola subsynthem (MLM1), HTR: MIS 12–10, ATR: MIS 11; VI) Undifferentiated continental unit (UCI), HTR: MIS 11–6.2, ATR: MIS 9.3–7.1; VII) Foggia synthem (TGF), ATR: MIS 6; VIII) Masseria Finamondo synthem (TPF), ATR: Upper Pleistocene; IX) Carapelle and Cervaro streams synthem (RPL), subdivided into: IXa) Incoronata subsynthem (RPL1), HTR: MIS 6–3; ATR: MIS 5–3; IXb) Marane La Pidocchiosa–Castello subsynthem (RPL3), ATR: Holocene; X) Masseria Inacquata synthem (NAQ), ATR: Holocene. The possibility of recognizing and dating Quaternary units in an alluvial plain to the scale of a marine isotope stage constitutes a clear step forward compared with similar studies regarding other alluvial-plain areas, where Quaternary units were dated almost exclusively using their stratigraphic position. As a result, they were generically associated with a geological sub-epoch. Instead, our method allowed a higher detail in the timing of the sedimentary processes: for example, MIS 11 and MIS 5.5 deposits have been recognized and characterized for the first time in the study area, highlighting their importance as phases of sedimentation.

Flow of a micropolar fluid bounded by a stretching sheet

We consider boundary layer flow of a micropolar fluid driven by a porous stretching sheet. A similarity solution is defined, and numerical solutions using Runge-Kutta and quasilinearisation schemes are obtained. A perturbation analysis is also used to derive analytic solutions to first order in the perturbing parameter. The resulting closed form solutions involve relatively complex expressions, and the analysis is made more tractable by a combination of offline and online work using a computational algebra system (CAS). For this combined numerical and analytic approach, the perturbation analysis yields a number of benefits with regard to the numerical work. The existence of a closed form solution helps to discriminate between acceptable and spurious numerical solutions. Also, the expressions obtained from the perturbation work can provide an accurate description of the solution for ranges of parameters where the numerical approaches considered here prove computationally more difficult.

Discourse practice gaps in work life balance : comparative case studies in the Australian construction industry

Perspectives on work-life balance (WLB) reflected in political, media and organisational discourse, would maintain that WLB is on the agenda because of broad social, economic and political factors (Fleetwood 2007). In contrast, critical scholarship which examines work-life balance (WLB) and its associated practices maintains that workplace flexibility is more than a quasi-functionalist response to contemporary problems faced by individuals, families or organisations. For example, the literature identifies where flexible work arrangements have not lived up to expectations of a panacea for work-home conflicts, being characterised as much by employer-driven working conditions that disadvantage workers and constrain balance, as they are by employee friendly practices that enable it (Charlesworth 1997). Further, even where generous organisational work-life balance policies exist, under-utilisation is an issue (Schaefer et al, 2007). Compounding these issues is that many employees perceive their paid work as becoming more intense, pressured and demanding (Townsend et al 2003).

Community food security gaps in surveillance and monitoring

This paper describes the gaps in monitoring and surveillance identified while conducting Community Food Security assessments in three geographical areas located in south-east Queensland, Australia

Bahrain skills gaps study : tourism, construction, and education skills plans

The tourism, construction, and education plans and skills strategies (embedded in project reports) were developed as part of a nation-wide comprehensive research project covering current, emerging and future skills deficiencies and requirements in Bahrain’s labour market. The research covered the majority of economic sectors and activities in the Kingdom and will serve as a basis for formulating industry and occupational outlooks as well as career guidance and awareness activities by academic and training institutions across Bahrain. It will provides foundation work for industry skills councils in order to conduct and achieve a uniform system of occupational standards across industries, occupations and job levels.

Attitudes towards inclusion : gaps between belief and practice

General education teachers in the Republic of Korea were investigated regarding their participation in programs to include students with disabilities in general education settings. Previous studies have shown that even general education teachers with positive attitudes towards inclusion are reluctant in practice to have students with disabilities in their classrooms. This study examines 33 Korean general education teachers from three primary schools in Seoul regarding their attitudes towards, and willingness to accommodate, the needs of a student with a disability. The results show that 41.37% of general education teachers had positive attitudes towards inclusion programs, while 55.16% were unwilling to actually participate. Quantitative data obtained through a questionnaire was supplemented by qualitative data obtained through interviews. The interviews focused on the positive and negative effects of inclusion, as well as problems in implementing inclusive education programs. The findings will be discussed in the light of previous international research and will highlight links between the age and teaching experience of general education teachers and their negative attitudes towards inclusion.

Bounded parameter Markov Decision Processes with average reward criterion

Bounded parameter Markov Decision Processes (BMDPs) address the issue of dealing with uncertainty in the parameters of a Markov Decision Process (MDP). Unlike the case of an MDP, the notion of an optimal policy for a BMDP is not entirely straightforward. We consider two notions of optimality based on optimistic and pessimistic criteria. These have been analyzed for discounted BMDPs. Here we provide results for average reward BMDPs. We establish a fundamental relationship between the discounted and the average reward problems, prove the existence of Blackwell optimal policies and, for both notions of optimality, derive algorithms that converge to the optimal value function.

Evaluation of green public road procurement in Australia : current practices and gaps to fill

Public road authorities have a key responsibility in driving initiatives for reducing greenhouse gas (GHG) emissions in the road construction project lifecycle. A coherent and efficient chain of procurement processes and methods is needed to convert green policies into tangible actions that capture the potential for GHG reduction. Yet, many infrastructure clients lack developed methodologies regarding green procurement practices. Designing more efficient solutions for green procurement requires an evaluation of the current initiatives and stages of development. A mapping of the current GHG reduction initiatives in Australian public road procurement is presented in this paper. The study includes the five largest Australian state road authorities, which cover 94% of the total 817,089 km of Australian main roads (not local) and account for 96% of the total A$13 billion annual major road construction and maintenance expenditure. The state road authorities’ green procurement processes and tools are evaluated based on interviews and a review of documents. Altogether 12 people, comprising 1-3 people of each organisation, participated in the interviews and provided documents. An evaluation matrix was developed for mapping the findings across the lifecycle of road construction project delivery. The results show how Australian state road authorities drive decisions with an impact on GHG emissions on the strategic planning phase, project development phase, and project implementation phase. The road authorities demonstrate varying levels of advancement in their green procurement methodologies. Six major gaps in the current green procurement processes are identified and, respectively, six recommendations for future research and development are suggested. The greatest gaps remain in the project development phase, which has a critical role in fixing the project (GHG reduction) goals, identifying risks and opportunities, and selecting the contractor to deliver the project. Specifically, the role of mass-haul optimisation as a part of GHG minimisation was reviewed, and mass-haul management was found to be an underutilised element with GHG reduction potential.

Helping understand nutritional gaps in the elderly (HUNGER) : a prospective study of patient factors associated with inadequate nutritional intake in older medical inpatients

BACKGROUND: Malnutrition, and poor intake during hospitalisation, are common in older medical patients. Better understanding of patient-specific factors associated with poor intake may inform nutritional interventions. AIMS: To measure the proportion of older medical patients with inadequate nutritional intake, and identify patient-related factors associated with this outcome. METHODS: Prospective cohort study enrolling consecutive consenting medical inpatients aged 65 years or older. Primary outcome was energy intake less than resting energy expenditure estimated using weight-based equations. Energy intake was calculated for a single day using direct observation of plate waste. Explanatory variables included age, gender, number of co-morbidities, number of medications, diagnosis, usual residence, nutritional status, functional and cognitive impairment, depressive symptoms, poor appetite, poor dentition, and dysphagia. RESULTS: Of 134 participants (mean age 80 years, 51% female), only 41% met estimated resting energy requirements. Mean energy intake was 1220 kcal/day (SD 440), or 18.1 kcal/kg/day. Factors associated with inadequate energy intake in multivariate analysis were poor appetite, higher BMI, diagnosis of infection or cancer, delirium and need for assistance with feeding. CONCLUSIONS: Inadequate nutritional intake is common, and patient factors contributing to poor intake need to be considered in nutritional interventions.

The effect of very small air gaps on small field dosimetry

The purpose of this study was to investigate the effect of very small air gaps (less than 1 mm) on the dosimetry of small photon fields used for stereotactic treatments. Measurements were performed with optically stimulated luminescent dosimeters (OSLDs) for 6 MV photons on a Varian 21iX linear accelerator with a Brainlab μMLC attachment for square field sizes down to 6 mm × 6 mm. Monte Carlo simulations were performed using EGSnrc C++ user code cavity. It was found that the Monte Carlo model used in this study accurately simulated the OSLD measurements on the linear accelerator. For the 6 mm field size, the 0.5 mm air gap upstream to the active area of the OSLD caused a 5.3 % dose reduction relative to a Monte Carlo simulation with no air gap. A hypothetical 0.2 mm air gap caused a dose reduction > 2 %, emphasizing the fact that even the tiniest air gaps can cause a large reduction in measured dose. The negligible effect on an 18 mm field size illustrated that the electronic disequilibrium caused by such small air gaps only affects the dosimetry of the very small fields. When performing small field dosimetry, care must be taken to avoid any air gaps, as can be often present when inserting detectors into solid phantoms. It is recommended that very small field dosimetry is performed in liquid water. When using small photon fields, sub-millimetre air gaps can also affect patient dosimetry if they cannot be spatially resolved on a CT scan. However the effect on the patient is debatable as the dose reduction caused by a 1 mm air gap, starting out at 19% in the first 0.1 mm behind the air gap, decreases to < 5 % after just 2 mm, and electronic equilibrium is fully re-established after just 5 mm.

Gaps in organizational leadership : linking strategic and operational activities through design-led propositions

The relationship between design process and business systems has been of interest to both practitioners and researchers exploring the numerous opportunities and challenges of this unlikely relationship. Often the relationship is presented as building design thinking capability within an organization, which can be broadly described as the union of design and strategy. Brown (2008) notes that design thinking is ‘‘a discipline that uses the designer’s sensibility and methods to match people’s needs with what is technically feasible and what business strategy can convert into customer value and market opportunities’’ (p. 1). The value that design thinking brings to an organization is a different way of framing situations and possibilities, doing things, and tackling problems: essentially a cultural transformation of the way it undertakes its business. The work of Martin (2009) has clearly shown the generalized differences between design thinking and business thinking, highlighting many instances in which these differences have been overcome, but also noting the many obstacles of trying to unify both approaches within an organization. Liedtka (2010) encourages firms to try and persist in overcoming these barriers, as she has noted that ‘‘business strategy desperately needs design ... because design is all about action and business strategy too often turns out to be only about talk ... fewer than 10 percent of new strategies are ever fully executed’’ (p. 9).

The legitimation and reproduction of discourse-practice gaps in work-life balance

Purpose - Critical scholarship on work-life balance (WLB) and its associated practices maintains that workplace flexibility is more than a quasi-functionalist response to contemporary problems faced by individuals, families or organisations. Beginning with Fleetwood’s contention that WLB discourses have become "detached" from their associated practices, this paper explores how workplace practices support or challenge dominant WLB discourses evident in socio-cultural, political and organisational sources. Design/methodology/approach - We analyse individual and group interview transcripts derived from 122 white-collar employees in two different organisational contexts (one public, one private) in the construction industry in Australia. Findings - Four major themes were identified in the data which illustrate discourse practice gaps. First, the demands facing this particular industry/ sector were framed as heightened and unique. Second, productivity was prioritised, dominating employees’ care-giving and lifestyle concerns. Third, employees’ caring responsibilities were communicated as personal and individual choices. Fourth, commitment and efficiency were judged on the basis of presence in the workplace. Research limitations/implications - Even in industries that have embraced WLB, workplace practices legitimate and reinforce the status quo, and maintain a gap between the promises of WLB and its potential to ameliorate conflict and assist workers to span the boundaries of paid work and other life domains. Originality/value - While the practices demonstrated in the research are focused on one industry, the study provides a critical analysis of how the contextually-influenced meaning of WLB is constructed, created and contested in these workplaces and the effects it produces.