21 resultados para Open-system Fractional Crystallization

em Deakin Research Online - Australia


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An investigation of the viability of commercial tomato production using the Autopot growing system in Australia. The Autopot system is a relatively new hydroponic production system technology that is being introduced onto the market in competition with traditional systems. Although commercial tomato production was found to be significantly more water and nutrient efficient in the Autopot system than in a traditional open system, yields were significantly lower. Financial modelling shows that tomato production in this system would not be commercially viable in Australia for a typical tomato growing venture under current conditions.

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This paper serves to specify and ground research into interfunctional integration in a wider theoretical context with particular reference to the interaction between technology and marketing in the biotechnology sphere. The general and specific problem areas are specified as those of interfunctional relations and the dyadic relationship between marketing and biotechnical managerial functions in particular. The contextual/organisational generative mechanisms that are likely to keep interfunctional relations at the centre of scholarly attention for some time are explored from the perspective of cybernetic theory. The law of requisite variety states that in an effective open system environmental variety is matched by internal structural variety. As organisations are faced with ever more turbulent, and complex environments, this must be matched by an increased internal complexity within the organisation. The two modes of response, namely holographic and mechanistic, both highlight the need to further our understanding of interfunctional differences. Having established the problem and its genesis, a specific research agenda is outlined as the exploration of the interfunctional differences from a decision-making perspective.

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The homoleptic 1:1 Lewis pair (LP) complex [MesTe(TeMes₂)]O₃SCF₃ (1) featuring the cation [MesTe(TeMes₂)]+ (1a) was obtained by the reaction of Mes₂Te with HO₃SCF₃. The reaction of 1 with Ph₃E (E = P, As, Sb, Bi) proceeded with substitution of Mes₂Te and provided the heteroleptic 1:1 LP complexes [MesTe(EPh₃)]O₃SCF₃ (2, E = P; 3, E = As) and [MesTe(SbPh₃)][Ph₂Sb(O₃SCF₃)₂] (4) featuring the cations [MesTe(EPh₃)]+ (2a, E = P; 3a, E = As; 4a, E = Sb) and the anion [Ph₂Sb(O₃SCF₃)₂]− (4b). In the reaction with Ph₃Bi, the crude product contained the cation [MesTe(BiPh₃)]+ (5a) and the anion [Ph₂Bi(O₃SCF₃)₂]− (5b); however, the heteroleptic 1:1 LP complex [MesTe(BiPh₃)][Ph₂Bi(O₃SCF₃)₂] (5) could not be isolated because of its limited stability. Instead, fractional crystallization furnished a large amount of Ph₂BiO₃SCF₃ (6), which was also obtained by the reaction of Ph₃Bi with HO₃SCF₃. The formation of the anions 4b and 5b involves a phenyl group migration from Ph₃E (E = Sb, Bi) to the MesTe+ cation and afforded MesTePh as the byproduct, which was identified in the mother liquor. The heteroleptic 1:1 LP complexes 2–4 were also obtained by the one-pot reaction of Mes₂Te, Ph₃E (E = P, As, Sb) and HO₃SCF₃. Compounds 1–4 and 6 were investigated by single-crystal X-ray diffraction. The molecular structures of 1a–4a were used for density functional theory calculations at the B3PW91/TZ level of theory and studied using natural bond order (NBO) analyses as well as real-space bonding descriptors derived from an atoms-in-molecules (AIM) analysis of the theoretically obtained electron density. Additionally, the electron localizability indicator (ELI-D) and the delocalization index are derived from the corresponding pair density.

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Microphase separation through competitive hydrogen bonding interactions in ABC/D triblock copolymer/ homopolymer complexes is studied for the first time. This study investigated self-assembled nanostructures that are obtained in the bulk, by the complexation of a semicrystalline polystyrene-block-poly(4-vinylpyridine)-block-poly(ethylene oxide) (SVPEO) triblock copolymer with a poly(4-vinyl phenol) (PVPh) homopolymer in tetrahydrofuran (THF). In these complexes, microphase separation takes place due to the disparity in intermolecular interactions among PVPh/P4VP and PVPh/PEO pairs. At low PVPh concentrations, PEO interacts relatively weakly with PVPh, whereas in the complexes containing more than 30 wt% PVPh, the PEO block interacts considerably with PVPh, leading to the formation of composition-dependent nanostructures. SAXS and TEM results indicate that the cylindrical morphology of a neat SVPEO triblock copolymer changes into lamellae structures at 20 wt% of PVPh then to disordered lamellae with 40 wt% PVPh. Wormlike structures are obtained in the complex with 50 wt%PVPh, followed by disordered spherical microdomains with size in the order of 40–50 nm in the complexes with 60–80 wt% PVPh. Moreover, when the content of PVPh increases to 80 wt%, the complexes show a completely homogenous phase of PVPh/P4VP and PVPh/PEO with phase separated spherical PS domains. The fractional crystallization behavior in SVPEO and complexes at lower PVPh content was also examined. A structural model was proposed to explain the microphase separation and self-assembled morphologies of these complexes based on the experimental results obtained. The formation of nanostructures and changes in morphologies depend on the relative strength of hydrogen bonding interactions between each component block of the copolymer and the homopolymer.

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In autonomously managed distributed systems for collaboration, provenance can facilitate reuse of information that are interchanged, repetition of successful experiments, or to provide evidence for trust mechanisms that certain information existed at a certain period during collaboration. In this paper, we propose domain independent information provenance architecture for open collaborative distributed systems. The proposed system uses XML for interchanging information and RDF to track information provenance. The use of XML and RDF also ensures that information is universally acceptable even among heterogeneous nodes. Our proposed information provenance model can work on any operating systems or workflows.

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This study examined whether availability of public open spaces that can be used for recreation varies according to neighbourhood socio-economic disadvantage. Density and area of public open spaces were examined using a geographic information system and postal boundaries were used to define neighbourhoods. Neighbourhood socio-economic status (SES) was stratified into quintiles. Once neighbourhood population and geographic area were considered there were no differences in the number or total area of free-access, restricted access or sporting/recreation open spaces across quintiles of neighbourhood SES. Future research should examine whether the quality of public open spaces differ by neighbourhood SES.

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A system-of-systems (SoS) conceptualization is essential in resolving issues involving heterogeneous independently operable systems to achieve a unique purpose. Successful operation as an SoS requires communication among appropriate individuals and groups across enterprises through an effective protocol. This paper presents a position on the creation of a consortium of concerned system engineers and scientists worldwide to examine the problems and solutions strategies associated with SoS. The consortium could lead efforts in clarifying ambiguities and in seeking remedies to numerous open questions with respect to SoS analysis, SoS engineering (SoSE), as well as differences between systems engineering (SE) and SoSE. The mission of this consortium is envisioned to: 1) act as a neutral party; 2) provide a forum to put forth Calls to Action; and 3) establish a community of interest to recommend a set of solutions.

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To use the vast amount of information efficiently and effectively from Web sites is very important for making informed decisions. There are, however, still many problems that need to be overcome in the information gathering research arena to enable the delivery of relevant information required by users. In this paper, an information gathering system is develop by means of multiple agents to solve those problems. We employed some ideas of Gaia's methodology and an open agent architecture to analyze and design the system. The system consists of a query preprocessing agent, information retrieval agent, information filtering agent, and information management agent. The filtering agent is trained with categorized documents and can provide users with the necessary information. The experimental results show that all agents in the system can work cooperatively to retrieve relevant information from the World Wide Web environment.

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Objective : To examine associations between features of public open spaces, and children's physical activity.
Participants : 163 children aged 8–9 years and 334 adolescents aged 13–15 years from Melbourne, Australia participated in 2004.
Methods : A Geographic Information System was used to identify all public open spaces (POS) within 800 m of participants' homes and their closest POS. The features of all POS identified were audited in 2004/5. Accelerometers measured moderate-to-vigorous physical activity (MVPA) after school and on weekends. Linear regression analyses examined associations between features of the closest POS and participants' MVPA.
Results : Most participants had a POS within 800 m of their home. The presence of playgrounds was positively associated with younger boys' weekend MVPA (B = 24.9 min/day; p ≤ 0.05), and lighting along paths was inversely associated with weekend MVPA (B = − 54.9 min/day; p ≤ 0.05). The number of recreational facilities was inversely associated with younger girls' MVPA after school (B = − 2.6 min/day; p ≤ 0.05) and on the weekend (B = − 8.7 min/day; p ≤ 0.05). The presence of trees providing shade (5.8 min/day, p ≤ 0.01) and signage regarding dogs (B = 6.8 min/day, p ≤ 0.05) were positively associated with adolescent girls' MVPA after school.
Conclusion : Certain features of POS were associated with participants' MVPA, although mixed associations were evident. Further research is required to clarify these complex relationships.

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This study examined the relations between neighbourhood socio-economic status and features of public open spaces (POS) hypothesised to influence children's physical activity. Data were from the first follow-up of the Children Living in Active Neighbourhoods (CLAN) Study, which involved 540 families of 5–6 and 10–12-year-old children in Melbourne, Australia. The Socio-Economic Index for Areas Index (SEIFA) of Relative Socio-economic Advantage/Disadvantage was used to assign a socioeconomic index score to each child's neighbourhood, based on postcode. Participant addresses were geocoded using a Geographic Information System. The Open Space 2002 spatial data set was used to identify all POS within an 800 m radius of each participant's home. The features of each of these POS (1497) were audited. Variability of POS features was examined across quintiles of neighbourhood SEIFA. Compared with POS in lower socioeconomic neighbourhoods, POS in the highest socioeconomic neighbourhoods had more amenities (e.g. picnic tables and drink fountains) and were more likely to have trees that provided shade, a water feature (e.g. pond, creek), walking and cycling paths, lighting, signage regarding dog access and signage restricting other activities. There were no differences across neighbourhoods in the number of playgrounds or the number of recreation facilities (e.g. number of sports catered for on courts and ovals, the presence of other facilities such as athletics tracks, skateboarding facility and swimming pool). This study suggests that POS in high socioeconomic neighbourhoods possess more features that are likely to promote physical activity amongst children.

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This article reports the nonisothermal crystallization behavior of MXD6 and its clay nanocomposite system (MXD6/MMT) using differential scanning calorimetry (DSC). The DSC experimental data were analyzed by theoretical modeling of the crystallization kinetics using the Avrami, Ozawa, Jeziorny, and the combined Avrami―Ozawa semiempirical models. It has been determined that these models adequately described the crystallization behavior of the MXD6 nanocomposite at cooling rates below 20 °C/min, but there was a deviation from linear dependence at higher cooling rates. This was attributed to changes of both the free energy and the cooling crystallization function K(T) over the entire crystallization process, as well as possible relaxation effects leading to structural rearrangements. In addition, the activation energy determined using the differential isoconversional method of Friedman was also found to vary, indicating changes in both the free energy and crystallization mechanism. Despite the lack of a reliable theoretical model, the heterogeneous nucleating activity of the MMT nanoparticles was demonstrated and quantified using Dobreva's method (Φ = 0.71), and the crystallization rate for the nanocomposite system was found to be greater than pure MXD6 by up to 79% at 40 °C/min.

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Although information communication technology (ICT) tool is long regard as very useful in today’s engineering, architectural and construction management, organizations cannot just only simply operate based upon its origin, but also requires the on-going observation, controlling measures, monitoring aids, adding features and fine-tuning actions to such tool before the desirable outcome can be achieved. However, it is a very common phenomenon that organizations purchase the licensed “off-the-shelf-software” ICT package and customize it to suit their own requirements. Due to the incapability and inefficiency of such software and customization, the possible result is making such tool becomes not user-friendly and obsolete.

The purpose of this paper therefore, as part of the doctoral research, is to review and report those actions taken by a construction organization to enhance the performance of its Enterprise Resource Planning (ERP) system upon launching it since December 2002. Such actions include: improving data inputting method; removing the transition bottleneck; introducing crystallization function; revising the organization’s “Delegation and Limits of Authority”; publishing the “League Table” amongst users; integrating the 3D Modeling into the system and adopting the “Resources Requirement Planning”.

Whilst the ultimate goals of this system are well beyond the time limit of the research project, an obvious interim result, achieved by this case studied organization, was winning a landmark project worth HK$5 billion after the ERP system was functioned effectively. The experience and success of this organization can be borrowed by those companies which are planning to adopt information technology (IT) strategy and use ICT tool in the architectural management system.

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Reputation systems are very useful in large online communities in which users may frequently have the opportunity to interact with users with whom they have no prior experience. Recently, how to enhance the cooperative behaviors in the reputation system has become to one of the key open issues. Emerging schemes focused on developing efficient reward and punishment mechanisms or capturing the social or economic properties of participants. However, whether this kind of method can work widely or not has been hard to prove until now. Research in evolutionary game theory shows that group selection (or multilevel selection) can favor the cooperative behavior in the finite population. Furthermore, some recent works give fundamental conditions for the evolution of cooperation by group selection. In the paper, we extend the original group selection theory and propose a group-based scheme to enhance cooperation for online reputation systems. Related concepts are defined to capture the social structure and ties among participants in reputation system, e.g., group, assortativity, etc. Also, we use a Fermi distribution function to reflect the bounded rationality of participants and the existence of stochastic factors in evolutionary process. Extended simulations show that our scheme can enhance cooperation and improve the average performance of participants (e.g. payoff) in reputation system.

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The management of social, economic, and ecological assets in coastal zones is fundamental to the maintenance and sustainability of coastal resources. A significant issue in this discussion is the role of governance structures. In Australia the governance of the coastal zone includes a range of institutional authorities, processes, and procedures that set the context for decision making about coastal management. As well as the formal institutional arrangements there is also a maze of other interests such as development commissions, NGOs, Indigenous Native Title holders and other stakeholders including recreational interests. A major issue for governance arrangements is the considerable gap that often exists between how those interests interpret and develop their positions especially when the knowledge is derived from different systems – scientific, managerial, lay and indigenous. This paper will explore the development of an Estuary Entrance Management Support System (EEMSS) in south west Victoria Australia. The EEMSS is a decision support tool to assist estuary managers in determining whether to artificially open a river mouth. A significant part of the process adopted was community participation which involved a ‘steps’ approach to engage local community groups and landholders. It is the process of engaging different knowledge systems in a meaningful conversation that has led to a system that now gains support from all of the stakeholders in the management of different estuaries. The paper will discuss the processes that surround the EEMSS and outline some lessons that arise in context of the ‘project state’.

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Remote technologies are changing our way of life. The radio frequency identification (RFJD) system is a new technology which uses the open air to transmit information. This information transmission needs to be protected to provide user safety and privacy. Business will look for a 5ystem that hasfraud resilience to prevent the misuse of information to take dishonest advantage. The business and the user need to be assured that the transmitted information has no content which is capable of undertaking malicious activities. Public awareness of RFID security will help users and organizations to understand the need for security protection. Publishing a security guideline from the regulating body and monitoring implementation of that guideline in RFID 5ystems will ensure that businesses and users are protected. This chapter explains the importance of security in a RFID system and will outline the protective measures. It also points out the research direction of RFID 5ystems.