964 resultados para strategisches Controlling


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The usual practice to study a large power system is through digital computer simulation. However, the impact of large scale use of small distributed generators on a power network cannot be evaluated strictly by simulation since many of these components cannot be accurately modelled. Moreover, the network complexity makes the task of practical testing on a physical network nearly impossible. This study discusses the paradigm of interfacing a real-time simulation of a power system to real-life hardware devices. This type of splitting a network into two parts and running a real-time simulation with a physical system in parallel is usually termed as power-hardware-in-the-loop (PHIL) simulation. The hardware part is driven by a voltage source converter that amplifies the signals of the simulator. In this paper, the effects of suitable control strategy on the performance of PHIL and the associated stability aspects are analysed in detail. The analyses are validated through several experimental tests using an real-time digital simulator.

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Recent controversy on the quantum dots dephasing mechanisms (between pure and inelastic) is re-examined by isolating the quantum dots from their substrate by using the appropriate limits of the ionization energy theory and the quantum adiabatic theorem. When the phonons in the quantum dots are isolated adiabatically from the phonons in the substrate, the elastic or pure dephasing becomes the dominant mechanism. On the other hand, for the case where the phonons from the substrate are non-adiabatically coupled to the quantum dots, the inelastic dephasing process takes over. This switch-over is due to different elemental composition in quantum dots as compared to its substrate. We also provide unambiguous analysis as to understand why GaAs/AlGaAs quantum dots may only have pure dephasing while InAs/GaAs quantum dots give rise to the inelastic dephasing as the dominant mechanism. It is shown that the elemental composition plays an important role (of both quantum dots and substrate) in evaluating the dephasing mechanisms of quantum dots.

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The surface of cubic silicon carbide (3C-SiC) hetero-epitaxial films grown on the (111) surface of silicon is a promising template for the subsequent epitaxial growth of III-V semiconductor layers and graphene. We investigate growth and post-growth approaches for controlling the surface roughness of epitaxial SiC to produce an optimal template. We first explore 3C-SiC growth on various degrees of offcut Si(111) substrates, although we observe that the SiC roughness tends to worsen as the degree of offcut increases. Hence we focus on post-growth approaches available on full wafers, comparing chemical mechanical polishing (CMP) and a novel plasma smoothening process. The CMP leads to a dramatic improvement, bringing the SiC surface roughness down to sub-nanometer level, though removing about 200 nm of the SiC layer. On the other hand, our proposed HCl plasma process appears very effective in smoothening selectively the sharpest surface topography, leading up to 30% improvement in SiC roughness with only about 50 nm thickness loss. We propose a simple physical model explaining the action of the plasma smoothening.

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Commonwealth legislation covering insurance contracts contains numerous provisions designed to control the operation and effect of terms in life and general insurance contracts. For example, the Life Insurance Act 1995 (Cth) contains provisions regulating the consequences attendant upon incorrect statements in proposals [1] and non-payment of premiums, [2] provides that an insurer may only exclude liability in the case of suicide if it has made express provision for such contingency in its policy, [3] and severely restricts the efficacy of conditions as to war risks. [4] The Insurance Contracts Act 1984 (Cth) is even more intrusive and has a major impact upon contractual provisions in the general insurance field. It is beyond the scope of this note to explore all of these provisions in any detail but examples of controls and constraints imposed upon the operation and effect of contractual provisions include the following. A party is precluded from relying upon a provision in a contract of insurance if such reliance would amount to a failure to act with the utmost good faith. [5] Similarly, a policy provision which requires differences or disputes arising out of the insurance to be submitted to arbitration is void, [6] unless the insurance is a genuine cover for excess of loss over and above another specified insurance. [7] Similarly clause such as conciliation clauses, [8] average clauses, [9] and unusual terms [10] are given qualified operation. [11] However the provision in the Insurance Contracts Act that has the greatest impact upon, and application to, a wide range of insurance clauses and claims is s 54. This section has already generated a significant volume of case law and is the focus of this note. In particular this note examines two recent cases. The first, Johnson v Triple C Furniture and Electrical Pty Ltd [2012] 2 Qd R 337, (hereafter the Triple C case), is a decision of the Queensland Court of Appeal; and the second, Matthew Maxwell v Highway Hauliers Pty Ltd [2013] WASCA 115, (hereafter the Highway Hauliers case), is a decision of the Court of Appeal in Western Australia. This latter decision is on appeal to the High Court of Australia. The note considers too the decision of the New South Wales Court of Appeal in Prepaid Services Pty Ltd v Atradius Credit Insurance NV [2013] NSWCA 252 (hereafter the Prepaid Services case).These cases serve to highlight the complex nature of s 54 and its application, as well as the difficulty in achieving a balance between an insurer and an insured's reasonable expectations.

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This cross-sectional study examined the association between controlling feeding practices and children's appetite traits. The secondary aim studied the relationship between controlling feeding practices and two proxy indicators of diet quality. Participants were 203 Australian-Indian mothers with children aged 1-5 years. Controlling feeding practices (pressure to eat, restriction, monitoring) and children's appetite traits (. food approach traits: food responsiveness, enjoyment of food, desire to drink, emotional overeating; food avoidance traits: satiety responsiveness, slowness in eating, fussiness and emotional undereating) were measured using self-reported, previously validated scales/questionnaires. Children's daily frequency of consumption of core and non-core foods was estimated using a 49-item list of foods eaten (yes/no) in the previous 24 hours as an indicator of diet quality. Higher pressure to eat was associated with higher scores for satiety responsiveness, slowness in eating, fussiness and lower score for enjoyment of food. Higher restriction was related to higher scores for food responsiveness and emotional overeating. Higher monitoring was inversely associated with fussiness, slowness in eating, food responsiveness and emotional overeating and positively associated with enjoyment of food. Pressure to eat and monitoring were related to lower number of core and non-core foods consumed in the previous 24 hours, respectively. All associations remained significant after adjusting for maternal and child covariates (n = 152 due to missing data). In conclusion, pressure to eat was associated with higher food avoidance traits and lower consumption of core foods. Restrictive feeding practices were associated with higher food approach traits. In contrast, monitoring practices were related to lower food avoidance and food approach traits and lower non-core food consumption.

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Parental controlling feeding practices have been directly associated with maladaptive child eating behaviours, such as Eating in the Absence of Hunger (EAH). The aim of this study was to examine EAH in very young children (3-4 years old) and to investigate the association between maternal controlling feeding practices and energy intake from a standardised selection of snacks consumed ‘in the absence of hunger’. Thirty-seven mother-child dyads enrolled in the NOURISH RCT participated in a modified EAH protocol conducted in the child’s home. All children displayed EAH, despite 80% reporting to be full or very full following completion of lunch 15 minutes earlier. The relationship between maternal and child covariates and controlling feeding practices and EAH were examined using non-parametric tests, and were stratified by child gender. For boys only, pressure to eat was positively associated with EAH. Neither restriction nor monitoring practices were associated with EAH in either boys or girls. Overall, the present findings suggest gender differences in the relationship between maternal feeding practices and children’s eating behaviours emerge early and should be considered in future research and intervention design.

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Barry recently attributed the non-significant relationship between the cultural dimensions of Individualism (IND) and Masculinity (MASC) to a suppression effect of regional differences. Pairing countries on regional proximity, he showed that a strong correlation between these cultural dimensions emerged. However, we point to significant issues with this analysis, including how countries were paired, ordered, and included/excluded, as well as in the cultural meaningfulness of regional proximity. Re-analysis of the data after addressing these issues shows that IND and MASC were not significantly related at a cultural level after controlling for regional proximity, nor after controlling for two other prominent geographic factors: latitude and climate demands. The weight of evidence suggests that IND and MASC are not correlated at a cultural level.

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Objective. To identify genomic regions linked with determinants of age at symptom onset, disease activity, and functional impairment in ankylosing spondylitis (AS). Methods. A whole genome linkage scan was performed in 188 affected sibling pair families with 454 affected individuals. Traits assessed were age at symptom onset, disease activity assessed by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), and functional impairment assessed by the Bath Ankylosing Spondylitis Functional Index (BASFI). Parametric and nonparametric quantitative linkage analysis was performed using parameters defined in a previous segregation study. Results. Heritabilities of the traits studied in this data set were as follows: BASDAI 0.49 (P = 0.0001, 95% confidence interval [95% CI] 0.23-0.75), BASFI 0.76 (P = 10-7, 95% CI 0.49-1.0), and age at symptom onset 0.33 (P = 0.005, 95% CI 0.04-0.62). No linkage was observed between the major histocompatibility complex (MHC) and any of the traits studied (logarithm of odds [LOD] score <1.0). "Significant" linkage (LOD score 4.0) was observed between a region on chromosome 18p and the BASDAI. Age at symptom onset showed "suggestive" linkage to chromosome 11p (LOD score 3.3). Maximum linkage with the BASFI was seen at chromosome 2q (LOD score 2.9). Conclusion. In contrast to the genetic determinants of susceptibility to AS, clinical manifestations of the disease measured by the BASDAI, BASFI, and age at symptom onset are largely determined by a small number of genes not encoded within the MHC.

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BACKGROUND: Monitoring studies revealed high concentrations of pesticides in the drainage canal of paddy fields. It is important to have a way to predict these concentrations in different management scenarios as an assessment tool. A simulation model for predicting the pesticide concentration in a paddy block (PCPF-B) was evaluated and then used to assess the effect of water management practices for controlling pesticide runoff from paddy fields. RESULTS: The PCPF-B model achieved an acceptable performance. The model was applied to a constrained probabilistic approach using the Monte Carlo technique to evaluate the best management practices for reducing runoff of pretilachlor into the canal. The probabilistic model predictions using actual data of pesticide use and hydrological data in the canal showed that the water holding period (WHP) and the excess water storage depth (EWSD) effectively reduced the loss and concentration of pretilachlor from paddy fields to the drainage canal. The WHP also reduced the timespan of pesticide exposure in the drainage canal. CONCLUSIONS: It is recommended that: (1) the WHP be applied for as long as possible, but for at least 7 days, depending on the pesticide and field conditions; (2) an EWSD greater than 2 cm be maintained to store substantial rainfall in order to prevent paddy runoff, especially during the WHP.

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Eight small-scale lysimeters with different excess water storage depths (EWSDs) were used to investigate the behavior of two herbicides, simetryn and thiobencarb, under paddy conditions. The concentration of simetryn dissipated similarly in all the lysimeters, while the thiobencarb concentration varied significantly because thiobencarb can adsorb onto the dissolved organic matter in a manure slurry, which was applied to six of the lysimeters. The herbicide losses (the percentage of the applied mass) from the lysimeters were reversely proportional with the EWSD. The correlation was stronger for simetryn than for thiobencarb. An appropriate EWSD is required to effectively prevent herbicide run-off from the paddy field, especially when a rainfall event occurs soon after herbicide application.

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Food retail is known for its use of flexible labour and for the centralisation of functions at head office, resulting in a reduction of managerial autonomy at store level. This article employs a typology of controls developed from labour process scholarship to explore how retail managers negotiate the control of their predominantly part-time workforce. Using an Australian supermarket chain as a case, and mixed methods, the article demonstrates that supermarkets use a multiplicity of forms of control across their workforce. For front line service workers, the article identifies a new configuration of controls which intersects with employment status and acts differentially for checkout operators on different employment contracts.

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MicroRNAs (miRNAs) are small non-coding RNAs of 20 nt in length that are capable of modulating gene expression post-transcriptionally. Although miRNAs have been implicated in cancer, including breast cancer, the regulation of miRNA transcription and the role of defects in this process in cancer is not well understood. In this study we have mapped the promoters of 93 breast cancer-associated miRNAs, and then looked for associations between DNA methylation of 15 of these promoters and miRNA expression in breast cancer cells. The miRNA promoters with clearest association between DNA methylation and expression included a previously described and a novel promoter of the Hsa-mir-200b cluster. The novel promoter of the Hsa-mir-200b cluster, denoted P2, is located 2 kb upstream of the 5′ stemloop and maps within a CpG island. P2 has comparable promoter activity to the previously reported promoter (P1), and is able to drive the expression of miR-200b in its endogenous genomic context. DNA methylation of both P1 and P2 was inversely associated with miR-200b expression in eight out of nine breast cancer cell lines, and in vitro methylation of both promoters repressed their activity in reporter assays. In clinical samples, P1 and P2 were differentially methylated with methylation inversely associated with miR-200b expression. P1 was hypermethylated in metastatic lymph nodes compared with matched primary breast tumours whereas P2 hypermethylation was associated with loss of either oestrogen receptor or progesterone receptor. Hypomethylation of P2 was associated with gain of HER2 and androgen receptor expression. These data suggest an association between miR-200b regulation and breast cancer subtype and a potential use of DNA methylation of miRNA promoters as a component of a suite of breast cancer biomarkers.

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The ability to deliver the drug to the patient in a safe, efficacious and cost-effective manner depends largely on the physicochemical properties of the active pharmaceutical ingredient (API) in the solid state. In this context, crystallization is of critical importance in pharmaceutical industry, as it defines physical and powder properties of crystalline APIs. An improved knowledge of the various aspects of crystallization process is therefore needed. The overall goal of this thesis was to gain better understanding of the relationships between crystallization, solid-state form and properties of pharmaceutical solids with a focus on a crystal engineering approach to design technological properties of APIs. Specifically, solid-state properties of the crystalline forms of the model APIs, erythromycin A and baclofen, and the influence of solvent on their crystallization behavior were investigated. In addition, the physical phenomena associated with wet granulation and hot-melting processing of the model APIs were examined at the molecular level. Finally, the effect of crystal habit modification of a model API on its tabletting properties was evaluated. The thesis enabled the understanding of the relationship between the crystalline forms of the model APIs, which is of practical importance for solid-state control during processing and storage. Moreover, a new crystalline form, baclofen monohydrate, was discovered and characterized. Upon polymorph screening, erythromycin A demonstrated high solvate-forming propensity thus emphasizing the need for careful control of the solvent effects during formulation. The solvent compositions that yield the desirable crystalline form of erythromycin A were defined. Furthermore, new examples on solvent-mediated phase transformations taking place during wet granulation of baclofen and hot-melt processing of erythromycin A dihydrate with PEG 6000 are reported. Since solvent-mediated phase transformations involve the crystallization of a stable phase and hence affect the dissolution kinetics and possibly absorption of the API these transformations must be well documented. Finally, a controlled-crystallization method utilizing HPMC as a crystal habit modifier was developed for erythromycin A dihydrate. The crystals with modified habit were shown to posses improved compaction properties as compared with those of unmodified crystals. This result supports the idea of morphological crystal engineering as a tool for designing technological properties of APIs and is of utmost practical interest.