969 resultados para Multiple-trait model


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Results are presented from a series of laboratory model studies of the flushing of saline water from a partially- or fully-closed estuary. Experiments have been carried out to determine quantitatively the response of the trapped saline volume to fresh water flushing discharges Q for different values of the estuary bed slope α and the density difference (∆ρ)o between the saline and fresh water. The trapped saline water forms a wedge within the estuary and for maintained steady discharges, flow visualisation and density profile data confirm that its response to the imposition of the freshwater purging flow occurs in two stages, namely (i) an initial phase characterised by intense shear-induced mixing at the nose of the wedge and (ii) a relatively quiescent second phase where the mixing is significantly reduced and the wedge is forced relatively slowly down and along the bed slope. Scalings based upon simple energy balance considerations are shown to be successful in (i) describing the time-dependent wedge behaviour and (ii) quantifying the proportion of input kinetic energy converted into increasing the potential energy of the wedge/river system. Measurements show that the asymptotic value of the energy conversion factor increases with increasing value of the river Froude number Fro at small values of Fro, thereafter reaching a maximum value and a gradual decrease at the highest values of Fro. Dimensional analysis considerations indicate that the normalised, time-dependent wedge position (xw)3(g')o/q2 can be represented empirically by a power-law relationship of the form (xw)[(g')o/q2]1/3 =C [(t)[(g')o2/q]1/3]"where the proportionality coefficient C is a function of both Fro and the slope angle α and the exponent n has a value of 0.24. Successful attempts are made to relate the model data to existing field observations from a microtidal estuary.

Experiments with multiple, intermittent periodic flushing flows confirm the importance of the starting phase of each flushing event for the time dependent behaviour of the saline wedge after reaching equilibrium in the intervals between such events. For the parameter ranges investigated and for otherwise-identical external conditions, no significant differences are found in the position of the wedge between cases of sequential multiple flushing flows and steady single discharges of the same total duration.

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This study investigated the relation between the five-factor model (FFM) of personality trait domains and leadership effectiveness. Ninety-nine Australian Army commissioned officers completed the NEO Personality Inventory-Revised (NEO-PI-R; Costa & McCrae, 1992) and were rated by their superior officer on the Australian Army annual leadership effectiveness evaluation schedule. Participants indicated whether they had been selected to attend a leadership promotion course at the Army Command and Staff College, widely regarded within the Army as indicative of an officer's effectiveness. It was hypothesized that leadership effectiveness would be predicted by the personality trait domains of high Conscientiousness, Openness, Agreeableness, and Extraversion and by low Neuroticism. High Conscientiousness and low Extraversion scores predicted high leadership effectiveness and the likelihood of attending the leadership promotion course. High Openness scores also predicted the likelihood of attending the promotion course. The results support the utility of the FFM in exploring the role of personality in leadership effectiveness among military leaders.

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The recognition of behavioural elements in finance has caused major shifts in the analytic framework pertaining to ratio-based modeling of corporate collapse. The modeling approach so far has been based on the classical rational theory in behavioural economics, which assumes that the financial ratios (i.e., the predictors of collapse) are static over time. The paper argues that, in the absence of rational economic theory, a static model is flawed, and that a suitable model instead is one that reflects the heuristic behavioural framework, which is what characterises behavioural attributes of company directors and in turn influences the accounting numbers used in calculating the financial ratios. This calls for a dynamic model: dynamic in the sense that it does not rely on a coherent assortment of financial ratios for signaling corporate collapse over multiple time periods. This paper provides empirical evidence, using a data set of Australian publicly listed companies, to demonstrate that a dynamic model consistently outperforms its static counterpart in signaling the event of collapse. On average, the overall predictive power of the dynamic model is 86.83% compared to an average overall predictive power of 69.35% for the static model.

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This article describes the application and evaluation of a clinical nursing leadership model to enhance continence care in an inpatient rehabilitation setting for older adults. Multiple strategies were employed to optimize the uptake and sustainability of 3 practice initiatives: (1)  establishment of an enhanced role for wardbased nurses to provide clinical support to patients and other staff for the management of incontinence, (2) a new method for nursing assessment and management of bowel elimination, and (3) a framework for improved discharge care of patients with incontinence. Evaluation data indicated a high level of acceptance of the role of the ward-based continence resource nurses, improved assessment and management of bowel elimination, and enhanced discharge care for patients with incontinence. These initiatives were sustainable during a 2-year period after their introduction, despite the gradual withdrawal of the clinical leader.

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The Open Provenance Model is a model of provenance that is designed to meet the following requirements: (1) To allow provenance information to be exchanged between systems, by means of a compatibility layer based on a shared provenance model. (2) To allow developers to build and share tools that operate on such a provenance model. (3) To define provenance in a precise, technology-agnostic manner. (4) To support a digital representation of provenance for any 'thing', whether produced by computer systems or not. (5) To allow multiple levels of description to coexist. (6) To define a core set of rules that identify the valid inferences that can be made on provenance representation. This document contains the specification of the Open Provenance Model (v1.1) resulting from a community-effort to achieve inter-operability in the Provenance Challenge series.

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Riboflavin-responsive, multiple acylcoenzyme A dehydrogenase deficiency (RR-MAD), a lipid storage myopathy, is characterized by, among others, a decrease in fatty acid (FA) ß-oxidation capacity. Muscle uncoupling protein 3 (UCP3) is up-regulated under conditions that either increase the levels of circulating free FA and/or decrease FA ß-oxidation. Using a relatively large cohort of seven RR-MAD patients, we aimed to better characterize the metabolic disturbances of this disease and to explore the possibility that it might increase UCP3 expression. A battery of biochemical and molecular tests were performed, which demonstrated decreases in FA ß-oxidation and in the activities of respiratory chain complexes I and II. These metabolic alterations were associated with increases of 3.1- and 1.7-fold in UCP3 mRNA and protein expression, respectively. All parameters were restored to control values after riboflavin treatment. We postulate that the up-regulation of UCP3 in RR-MAD is due to the accumulation of muscle FA/acylCoA. RR-MAD is an optimal model to support the hypothesis that UCP3 is involved in the outward translocation of an excess of FA from the mitochondria and to show that, in humans, the effects of FA on UCP3 expression are direct and independent of fatty acid ß-oxidation.

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This paper describes the research supported by a recent AIQS research grant to develop a computer-based tool for sustainability modeling using multiple criteria. The model enables a sustainability index with an accept/reject threshold of one that has the potential to completely replace traditional net present value methods. Minimum performance benchmarks are prescribed and must be observed - often by trading off performance across the full criteria set. Sustainability is shown to be capable of objective (numeric) analysis for new projects, existing facilities, or indeed any product or asset. A combination of investor-centred and community-centred motivations can also be explored in the model. Known as SINDEX, the tool has industry-wide application, both locally and abroad, and represents a paradigm shift in project evaluation techniques. Furthermore, its multi-discipline considerations underscore the importance of a team approach to sustainability modeling and the need for people to work more closely together when dealing with complex problems

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One common drawback in algorithms for learning Linear Causal Models is that they can not deal with incomplete data set. This is unfortunate since many real problems involve missing data or even hidden variable. In this paper, based on multiple imputation, we propose a three-step process to learn linear causal models from incomplete data set. Experimental results indicate that this algorithm is better than the single imputation method (EM algorithm) and the simple list deletion method, and for lower missing rate, this algorithm can even find models better than the results from the greedy learning algorithm MLGS working in a complete data set. In addition, the method is amenable to parallel or distributed processing, which is an important characteristic for data mining in large data sets.

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This paper attempts to study the propagating characteristics of acoustic signals emitted from the breakdown of air using time domain numerical model. Acoustic emissions are produced by high voltage faults such as partial discharge and surface discharge. Study of such emissions has become popular among researchers because of the promising correlation between partial and surface discharges and its byproduct, acoustic signal emission. In this paper, propagation characteristics of acoustic signals are studied using finite difference time domain (FDTD) method. Multiple monitoring points are placed within a designated computation space at different distance away from a source.

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This study examined the influence of trait resilience and trait anxiety on self-esteem and investigated the mediating role of positive and negative affect in this relationship. Specifically, it was proposed that trait resilience and trait anxiety may exert indirect effects on self-esteem by promoting increased positive and negative affect, respectively. The final sample comprised of 240 participants (age, M = 21.55, SD = 4.16) who completed questionnaire measures of trait resilience (CD-RISC; Connor & Davidson, 2003), trait anxiety (STAI-T; Spielberger, Gorsuch, Lushene, Vagg, & Jacobs, 1983), affect (PANAS; Watson, Clark, & Tellegen, 1988) and self-esteem (RSES; Rosenberg, 1965). Path analyses (AMOS), controlling for measurement error revealed significant indirect effects of trait anxiety and trait resilience on self-esteem via negative and positive affect. The indirect model provided a very close fit to the data; estimation of the full model (direct paths) did not yield a significantly better fit. It was concluded that the impact of trait anxiety and trait resilience on self-esteem may be due to their effects on regulating affective experiences which in turn may be more proximal predictors of individual feelings of self-worth.

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The freshman year of college is a period of heightened risk for weight gain. This study examined measures of restrained eating, disinhibition, and emotional eating as predictors of weight gain during the freshman year. Using Lowe's multi-factorial model of dieting, it also examined three different types of dieting as predictors of weight gain. Sixty-nine females were assessed at three points during the school year. Weight gain during the freshman year averaged 2.1 kg. None of the traditional self-report measures of restraint, disinhibition, or emotional eating were predictive of weight gain. However, both a history of weight loss dieting and weight suppression (discrepancy between highest weight ever and current weight) predicted greater weight gain, and these effects appeared to be largely independent of one another. Individuals who said they were currently dieting to lose weight gained twice as much (5.0 kg) as former dieters (2.5 kg) and three times as much as never dieters (1.6 kg), but the import of this finding was unclear because there was only a small number of current dieters (N=7). Overall the results indicate that specific subtypes of dieting predicts weight gain during the freshman year better than more global measures of restraint or overeating.

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A C-Mn-Nb-Ti steel was deformed by hot torsion to study ultrafine ferrite formation through dynamic strain-induced transformation (DSIT) in conjunction with air cooling. A systematic study was carried out first to evaluate the effect of deformation temperature and prior austenite grain size on the critical strain for ultrafine ferrite formation (ε C,UFF) through single-pass deformation. Then, multiple deformations in the nonrecrystallization region were used to study the effect of thermomechanical parameters (i.e., strain, deformation temperature, etc.) on ε C,UFF. The multiple deformations in the nonrecrystallization region significantly reduced ε C,UFF, although the total equivalent strain for a given thermomechanical condition was higher than that required in single-pass deformation. The current study on a Ni-30Fe austenitic model alloy revealed that laminar microband structures were the key intragranular defects in the austenite for nucleation of ferrite during the hot torsion test. The microbands were refined and overall misorientation angle distribution increased with a decrease in the deformation temperature for a given thermomechanical processing condition. For nonisothermal multipass deformation, there was some contribution to the formation of high-angle microband boundaries from strains at higher temperature, although the strains were not completely additive.

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Implementation of integrated catchment management (ICM) is hampered by the lack of a conceptual framework for explaining how landowners select farming systems for their properties. Benefit–cost analysis (a procedure that estimates the costs and benefits of alternative actions or policies) has limitations in this regard, which might be overcome by using multiple-criteria decision analysis (MCDA). MCDA evaluates and ranks alternatives based on a landowner's preferences (weights) for multiple-criteria and the values of those criteria. A MCDA approach to ICM is superior to benefit–cost analysis which focuses only on the monetary benefits and costs, because it: 1) recognizes that human activities within a catchment are motivated by multiple and often competing criteria and/or constraints; 2) does not require monetary valuation of criteria; 3) allows trade-offs between criteria to be measured and evaluated; 4) explicitly considers how the spatial configuration of farming systems in a catchment influences the values of criteria; 5) is comprehensive, knowledge-based, and stakeholder oriented which greatly increases the likelihood of resolving catchment problems; and 6) allows consideration of the fairness and sustainability of land and water resource management decisions. A MCDA based on an additive, multiple-criteria utility function containing five economic and environmental criteria was used to score and rank five farming systems. The rankings were based on the average criteria weights for a sample of 20 farmers in a US catchment. The most profitable farming system was the lowest-ranked farming system. Three possible reasons for this result are evaluated. First, the MCDA method might cause respondents to express socially acceptable attitudes towards environmental criteria even when they are not important from a personal viewpoint. Second, the MCDA method could inflate the ranks of less profitable farming systems for the simple reason that it allows the respondent to assign non-zero weights to non-economic criteria. Third, the MCDA might provide a better framework for evaluating a landowner's selection of farming systems than the profit maximization model.

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The mechanism of regional economic development has been studied extensively by economists, geographers, town planners and other academics. The existing wide varieties of theories into regional economic development are insufficient on their own in explaining how a region can develop and prosper. Each theory has evaluated a few facets of regional economic development. Research from these different perspectives is narrow and prevents any cross-fertilization of research from all these diverse
theories.

Recognition of multiple factors affecting the development process has led the author to create a new broad composite model of regional economic development. The paper first sets out to describe and explain this broad composite model. Each of the components of this new model draws heavily upon seminal work in the field. This model proposes three rings. Each ring is at a different level of abstraction. The determinants of development described in each ring can influence each and every other determinant of development shown in the three ring structure. This model recognises that development in any centre, regional or urban, nascent or established is a composite end result of the complex interplay of all the determinants of development.

The paper then goes on to show how this model can provide a broad holistic approach to regional economic development that can assist researchers in their attempts to understand and link the various theories of regional economic development.

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This paper describes development of a computer-based tool for sustainability modelling using multiple criteria, and preliminary conclusions from doctoral research being undertaken into the relationship between key sustainability indicators. The model used in both cases produces a sustainability index with an accept/reject threshold of one that has the potential to completely replace traditional net present value methods. Minimum performance benchmarks are prescribed and must be observed - often by trading off performance across the full criteria set. Sustainability is shown to be capable of objective (numeric)· analysis for new projects, existing facilities, or indeed any product or asset. A combination of investor-centred and community-centred motivations can also be explored in the model. Known as SINDEX, the tool has industry-wide application, both locally and abroad, and represents a paradigm shift in project evaluation techniques. Furthermore, its multi-discipline considerations underscore the importance of a team approach to sustainability modelling and the need for people to work more closely together when dealing with complex problems. The results of twenty case studies of actual high schools constructed and operated in New South Wales (Australia) are also presented and the relationships between the key sustainability indicators are explored and interpreted.