938 resultados para locus of control


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Invoking the resource-based view (RBV), this study investigates relationships between management control systems (MCSs) use, including information use from performance measurement systems (PMSs), and organisational capabilities in the context of academic units of Australian universities. Increased competition and attention to distinctive capabilities amongst universities, particularly at their strategic operating unit level of Schools 1, provides the setting for application of this theoretic perspective. The objective of this study is to model various relationships between diagnostic and interactive use of MCSs, attention given to centrally-imposed and discretionary types of PMS information, the strength of capabilities of the academic unit and, in turn, performance of the academic units. This objective is investigated using a field survey in which a mail survey instrument is administered to a census of all Heads of Schools in all 39 universities in Australia. Valid responses were received from 166 Heads. Principal components factor analysis finds that Heads conceived capabilities of their unit in functional dimensions, not in generic dimensions as found in prior literature; Heads also considered performance measures in terms of their importance (critical or discretionary) rather than type (financial versus non-financial). Partial least-squares analysis is then used for path modelling, and several significant results are obtained. Highlights are that diagnostic MCS use and centrally-imposed performance measures, i.e., key performance indicators, but not interactive MCS use or discretionary performance measures, significantly relate to some or all of the strength of capabilities in the fields of teaching, research and networking, and in turn indirectly relate to performance of the academic units. The findings have practical implications for styles of control systems use; focus on selected key performance measures; and development of organisational capabilities for achievement of superior performance by academic schools in universities.

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Population control of socially complex species may have profound ecological implications that remain largely invisible if only their abundance is considered. Here we discuss the effects of control on a socially complex top-order predator, the dingo (Canis lupus dingo). Since European occupation of Australia, dingoes have been controlled over much of the continent. Our aim was to investigate the effects of control on their abundance and social stability. We hypothesized that dingo abundance and social stability are not linearly related, and proposed a theoretical model in which dingo populations may fluctuate between three main states: (A) below carrying capacity and socially fractured, (B) above carrying capacity and socially fractured, or (C) at carrying capacity and socially stable. We predicted that lethal control would drive dingoes into the unstable states A or B, and that relaxation of control would allow recovery towards C. We tested our predictions by surveying relative abundance (track density) and indicators of social stability (scent-marking and howling) at seven sites in the arid zone subject to differing degrees of control. We also monitored changes in dingo abundance and social stability following relaxation and intensification of control. Sites where dingoes had been controlled within the previous two years were characterized by low scent-marking activity, but abundance was similar at sites with and without control. Signs of social stability steadily increased the longer an area was allowed to recover from control, but change in abundance did not follow a consistent path. Comparison of abundance and stability among all sites and years demonstrated that control severely fractures social groups, but that the effect of control on abundance was neither consistent nor predictable. Management decisions involving large social predators must therefore consider social stability to ensure their conservation and ecological functioning.

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Identification of unnatural control chart patterns (CCPs) from manufacturing process measurements is a critical task in quality control as these patterns indicate that the manufacturing process is out-of-control. Recently, there have been numerous efforts in developing pattern recognition and classification methods based on artificial neural network to automatically recognize unnatural patterns. Most of them assume that a single type of unnatural pattern exists in process data. Due to this restrictive assumption, severe performance degradations are observed in these methods when unnatural concurrent CCPs present in process data. To address this problem, this paper proposes a novel approach based on singular spectrum analysis (SSA) and learning vector quantization network to identify concurrent CCPs. The main advantage of the proposed method is that it can be applied to the identification of concurrent CCPs in univariate manufacturing processes. Moreover, there are no permutation and scaling ambiguities in the CCPs recovered by the SSA. These desirable features make the proposed algorithm an attractive alternative for the identification of concurrent CCPs. Computer simulations and a real application for aluminium smelting processes confirm the superior performance of proposed algorithm for sets of typical concurrent CCPs.

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1. Apex predators can benefit ecosystems through top–down control of mesopredators and herbivores. However, apex predators are often subject to lethal control aimed at minimizing attacks on livestock. Lethal control can affect both the abundance and behaviour of apex predators. These changes could in turn influence the abundance and behaviour of mesopredators.

2. We used remote camera surveys at nine pairs of large Australian rangeland properties, comparing properties that controlled dingoes Canis lupus dingo with properties that did not, to test the effects of predator control on dingo activity and to evaluate the responses of a mesopredator, the feral cat Felis catus.

3. Indices of dingo abundance were generally reduced on properties that practiced dingo control, in comparison with paired properties that did not, although the effect size of control was variable. Dingoes in uncontrolled populations were crepuscular, similar to major prey. In populations subject to control, dingoes became less active around dusk, and activity was concentrated in the period shortly before dawn.

4. Shifts in feral cat abundance indices between properties with and without dingo control were inversely related to corresponding shifts in indices of dingo abundance. There was also a negative relationship between predator visitation rates at individual camera stations, suggesting cats avoided areas where dingoes were locally common. Reduced activity by dingoes at dusk was associated with higher activity of cats at dusk.

5. Our results suggest that effective dingo control not only leads to higher abundance of feral cats, but allows them to optimize hunting behaviour when dingoes are less active. This double effect could amplify the impacts of dingo control on prey species selected by cats. In areas managed for conservation, stable dingo populations may thus contribute to management objectives by restricting feral cat access to prey populations.

6. Synthesis and applications. Predator control not only reduces indices of apex predator abundance but can also modify their behaviour. Hence, indicators other than abundance, such as behavioural patterns, should be considered when estimating a predator's capacity to effectively interact with lower trophic guilds. Changes to apex predator behaviour may relax limitations on the behaviour of mesopredators, providing enhanced access to resources and prey.

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It has been proposed that a sense of control (primary control) is critical to maintaining positive and stable subjective wellbeing (SWB). As people age and control capacity presumably declines (due to physical and cognitive deterioration and increased sociocultural challenges), it is argued that the influence of secondary perceived control (or acceptance) increases to help maintain normative levels of SWB. While previous studies have typically investigated the relationship between perceived control and global estimates of satisfaction (i.e., overall life satisfaction), the present study evaluated the link between perceived control and seven key domains of satisfaction in order to obtain a more comprehensive understanding of the control-satisfaction relationship. A community-based sample of 1,317 individuals (age range: 17–92 years) was utilised to examine potential age-related differences in perceived control (primary and secondary) and satisfaction. Findings revealed that primary and secondary perceived control both increased across age, with secondary perceived control increasing at a higher rate. Primary perceived control had predictive primacy for satisfaction over secondary perceived control (consistent with theory). A moderated mediation effect was also found, suggesting that, in later life, secondary perceived control influences primary perceived control and, in turn, influences satisfaction with various domains. Therefore, while primary control is important to wellbeing, it should be acknowledged that secondary perceived control may have unique significance to the wellbeing of older adults.

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Although control-related cognitions have often been implicated in discussions of obsessive compulsive disorder (OCD), empirical investigations of the relationship between control constructs and OCD symptoms have been relatively limited. This article investigated the hypothesis that OCD symptoms may be linked with a higher desire for control (DC), but a lower sense of control (SC) over the self and environment, leading to motivation for compulsive symptoms. It also investigated whether this effect was direct, or mediated through other OCD-related cognitions. This hypothesis was investigated in a nonclinical population, using path analyses controlling for depression. It was found that higher levels of DC and lower levels of SC were associated with higher levels of OCD-related beliefs, and with symptoms via higher OCD-related beliefs. SC was also directly linked with higher OCD symptoms. Control beliefs regarding both the internal (emotions) and external (threat) environment were related to OCD symptoms. Implications for therapy and research are discussed.

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A review of the state of knowledge in the field of control and energy management in HEVs is carried out. The key innovation of the project is the development of a model of a PHEV using the real road data with an intelligent look-ahead online controller. Another novelty of this work is the method of route planning. It combines the information of vehicle sensors such as accelerometer and speedometer with the data of a GPS to create a road grade map for use within the look-ahead energy management strategy in the vehicle. For the PHEV, an adaptive cruise controller is modelled and an optimisation method is applied to obtain the best speed profile during a trajectory. Finally, the nonlinear model of the vehicle is applied with the sliding mode controller. The effect of using this controller is compared with the universal cruise controller. The stability of the system is studied and proved.

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Invoking a resource-based view (RBV), this study investigates relationships between management control systems (MCSs) use, including information use from performance measurement systems (PMSs), and organisational capabilities in the context of academic units of Australian universities. Increased competition and attention to distinctive capabilities amongst universities, particularly at their strategic operating unit level of a Faculty1 or School2, provides the setting for application of this theoretic perspective. Based on a questionnaire survey of all Faculty Deans and Heads of Schools in all 39 universities in Australia, evidence is provided on relationships between diagnostic and interactive use of MCSs, attention given to imposed and discretionary types of PMS information, the strength of capabilities of the academic unit and, in turn, overall performance of the academic unit. Highlights of findings are that Heads/Deans conceived capabilities of their unit in functional dimensions, not in generic dimensions as found in prior literature; interactive MCS use and imposed performance measures, respectively, direct relate to several types of capabilities and indirectly to performance of the academic unit, but diagnostic MCS use does not. The findings have practical implications for styles of control systems use and performance information use by management in universities.

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The common starling (Sturnus vulgaris) has a proven invasion history in many countries, and at a continental scale in North America and Australasia. In Australia, starlings are firmly established throughout the eastern states and Tasmania. Incursions of starlings into Western Australia (WA) represent a significant threat to this State’s agricultural, public amenity and biodiversity assets. We present models of starling population dynamics that incorporate environmental and control effort variability. We incorporate knowledge of starling ecology with economic data to assess the potential economic cost of starlings establishing in WA, evaluating the cost–benefits for each management scenario. We calculated starling population size will approach carrying capacity in WA within as little as 30 years if left unchecked. A population of this size could cost the WA economy up to $43.7 million annually in 2011/2012 dollars. Over a 50 year horizon, the conservative benefit–cost ratio for ongoing detection and control at the current level of expenditure is 6.03:1. However, even under current levels of control, starling numbers are projected to increase to almost 11 million by 2061. Further improvements in the efficiency of starling detection and control and/or an increased level of expenditure on detection and control are required.

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We study the direct and indirect ownership structure of Brazilian corporations and their market value and risk by the end of 1996 and 1998. Ownership is quite concentrated with most companies being controlled by a single direct shareholder. We find evidence that indirect control structures may be used to concentrate control even more rather than to keep control of the company with a smaller share of total capital. The greater the concentration of voting rights then less the value of the fmn should be due to potential expropriation ofrninority shareholders. We fmd evidence that when there is a majority shareholder and when indirect ownership structures are used without the loss of control, corporate valuations are greater when control is dilluted through the indirect ownership structure. This evidence is consistent with the existence of private benefits of control that can be translated as potential minority shareholder expropriation.

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Larvae of Sciaridae flies (Diptera) cause considerable damage to the mushroom Agaricus blazei (Murrill) ss. Heinemann in Brazil. Brazilian growers have had considerable difficulties in controlling this pest. The objective of this work was to test the effect of the predatory Laelapidae mite Stratiolaelaps scimitus (Womersley) as a control agent of Bradysia matogrossensis (Lane) in cultures of A. blazei. The work corresponded to an evaluation of the efficiency of that predator when released in boxes containing each about 15 L of commercial mushroom compost naturally infested with the pest. The results showed a significant effect of that predator on the population of B. matogrossensis. The release of either 665 or 1330 S. scimitus per box significantly reduced the pest population to levels that, according to grower's experience, apparently could not cause considerable damage. The positive results obtained warrant the conduction of complementary studies to determine the lowest rates of the predator that could still produce acceptable levels of control.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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We present a two-colour photocurrent detection method for coherent control of a single InGaAs/GaAs self-assembled quantum dot. A pulse shaping technique provides a high degree of control over picosecond optical pulses. Rabi rotations on the exciton to biexciton transition are presented, and fine structure beating is detected via time-resolved measurements. (c) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

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In this article, we propose new control charts for monitoring the mean vector and the covariance matrix of bivariate processes. The traditional tools used for this purpose are the T (2) and the |S| charts. However, these charts have two drawbacks: (1) the T (2) and the |S| statistics are not easy to compute, and (2) after a signal, they do not distinguish the variable affected by the assignable cause. As an alternative to (1), we propose the MVMAX chart, which only requires the computation of sample means and sample variances. As an alternative to (2), we propose the joint use of two charts based on the non-central chi-square statistic (NCS statistic), named as the NCS charts. Once the NCS charts signal, the user can immediately identify the out-of-control variable. In general, the synthetic MVMAX chart is faster than the NCS charts and the joint T (2) and |S| charts in signaling processes disturbances.