982 resultados para EXCHANGE INTERACTION
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In this thesis, three mathematical models describing the growth of solid tumour incorporating the host tissue and the immune system response are developed and investigated. The initial model describes the dynamics of the growing tumour and immune response before being extended in the second model by introducing a time-varying dendritic cell-based treatment strategy. Finally, in the third model, we present a mathematical model of a growing tumour using a hybrid cellular automata. These models can provide information to pre-experimental work to assist in designing more effective and efficient laboratory experiments related to tumour growth and interactions with the immune system and immunotherapy.
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The interaction of water with the fluorine-covered (001) surface of anatase titanium dioxide (TiO2) has been studied within the framework of density functional theory (DFT). Our results show that water dissociation is unfavorable due to repulsive interactions between surface fluorine and oxygen. We also found that the reaction of hydrofluoric acid with a surface hydroxyl group to form a surface Ti–F bond is exothermic, while the removal of fluorine from the surface needs additional energy of about half an eV. Therefore, water molecules are predicted to remain intact at the interface with the F-terminated anatase (001).
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The impact-induced deposition of Al13 clusters with icosahedral structure on Ni(0 0 1) surface was studied by molecular dynamics (MD) simulation using Finnis–Sinclair potentials. The incident kinetic energy (Ein) ranged from 0.01 to 30 eV per atom. The structural and dynamical properties of Al clusters on Ni surfaces were found to be strongly dependent on the impact energy. At much lower energy, the Al cluster deposited on the surface as a bulk molecule. However, the original icosahedral structure was transformed to the fcc-like one due to the interaction and the structure mismatch between the Al cluster and Ni surface. With increasing the impinging energy, the cluster was deformed severely when it contacted the substrate, and then broken up due to dense collision cascade. The cluster atoms spread on the surface at last. When the impact energy was higher than 11 eV, the defects, such as Al substitutions and Ni ejections, were observed. The simulation indicated that there exists an optimum energy range, which is suitable for Al epitaxial growth in layer by layer. In addition, at higher impinging energy, the atomic exchange between Al and Ni atoms will be favourable to surface alloying.
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The communal nature of knowledge production predicts the importance of creating learning organisations where knowledge arises out of processes that are personal, social, situated and active. It follows that workplaces must provide both formal and informal learning opportunities for interaction with ideas and among individuals. This grounded theory for developing contemporary learning organisations harvests insights from the knowledge management, systems sciences, and educational learning literatures. The resultant hybrid theoretical framework informs practical application, as reported in a case study that harnesses the accelerated information exchange possibilities enabled through web 2.0 social networking and peer production technologies. Through complementary organisational processes, 'meaning making' is negotiated in formal face-to-face meetings supplemented by informal 'boundary spanning' dialogue. The organisational capacity building potential of this participatory and inclusive approach is illustrated through the example of the Dr. Martin Luther King, Jr. Library in San Jose, California, USA. As an outcome of the strategic planning process at this joint city-university library, communication, decision-making, and planning structures, processes, and systems were re-invented. An enterprise- level redesign is presented, which fosters contextualising information interactions for knowledge sharing and community building. Knowledge management within this context envisions organisations as communities where knowledge, identity, and learning are situated. This framework acknowledges the social context of learning - i.e., that knowledge is acquired and understood through action, interaction, and sharing with others. It follows that social networks provide peer-to-peer enculturation through intentional exchange of tacit information made explicit. This, in turn, enables a dynamic process experienced as a continuous spiral that perpetually elevates collective understanding and enables knowledge creation.
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Indonesia is a country spread across wide-ranging archipelago, located in South East Asia between two oceans, the Indian and the Pacific. Indonesia is well known as an active tectonic region because it lies on top of three major active tectonic plates: the Eurasian in the North, the Indian Ocean-Australian in the South, and the Pacific plate in the East. The southern and eastern part of the country features a range of volcanic arcs, volcanic mountains, and lowlands with 500 young volcanoes, of which 128 are active and thus representing 15% of the world’s active volcanoes. In the period 2002-2007, approximately 1782 disasters occurred, with hundreds of thousands of lives lost and billions of rupiah in losses incurred: (Floods - 1183 instances, cyclones - 272 instances, and landslides - 252 instances). Of these, the 2004 Aceh tsunami and the 2006 central Java earthquake (impacting predominantly city and suburbs of Yogyakarta) were the most significant. Even so, disaster management experts believe lessons learnt from the two major natural disasters needs to be formalised into laws and institutions before another disaster occurs, regardless of the type of natural disaster – i.e. Volcano eruption or landslide; as opposed to tsunami or earthquake. Following in the wake of disasters occurring in Yogyakarta, many of its community members responded by banding together as one, with the determination of rebuilding its villages and cities through the spirit of ‘gotong royong’. The idea of social interaction; in particular as a collective, consensual, and cooperative nation; has predominantly formed the ideological basis of Indonesia’s societal nature. Many Indonesian terms cohere to this ideology, such as: ‘koperasi” (cooperatives as the basis of economic interactions), ‘musyawarah’ (consensual nature in decision making), and ‘gotong royong’ (mutual assistance). ‘Gotong royong’ has become a key cultural operator in Indonesia, in particular In Jogjakarta. Appropriately so as ‘gotong royong’ is depicted from the traditional Javanese village, where labour is accomplished through reciprocal exchange and the villagers are motivated by a general ethos of selfishness and concern for the common good. The culture of ‘gotong royong’ promotes positive values such as social harmony and mutual reciprocation in disaster-affected areas provides the necessary spirit needed to endure the hardships and for all involved. While gotong royong emphasises the positive notions of mutual family support and deep community level activity there is a potential for contrast against government lead disaster response and recovery management activities especially in settings where sporadic governance mechanisms exist and transparency and accountability in the recovery process of public infrastructure assets have been questioned. This paper thus questions whether Gotong Royong is a double-edged sword, and explores the potential marriage of community values and governance mechanisms for future disaster management planning and practice.
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This study aims to redefine spaces of learning to places of learning through the direct engagement of local communities as a way to examine and learn from real world issues in the city. This paper exemplifies Smart City Learning, where the key goal is to promote the generation and exchange of urban design ideas for the future development of South Bank, in Brisbane, Australia, informing the creation of new design policies responding to the needs of local citizens. Specific to this project was the implementation of urban informatics techniques and approaches to promote innovative engagement strategies. Architecture and Urban Design students were encouraged to review and appropriate real-time, ubiquitous technology, social media, and mobile devices that were used by urban residents to augment and mediate the physical and digital layers of urban infrastructures. Our study’s experience found that urban informatics provide an innovative opportunity to enrich students’ place of learning within the city.
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The Guide includes research findings from the Australian Centre for Philanthropy and Non Profit Studies at the Queensland University of Technology (QUT). This research probed the experiences of fourteen Indigenous people who have had different degrees of success in seeking funding from philanthropic organisations. This research shows how grantmakers can make a significant difference in the lives of Aboriginal and Torres Strait Islander people.
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Road safety barriers are used to redirect traffic at roadside work-zones. When filled with water, these barriers are able to withstand low to moderate impact speeds up to 50kmh-1. Despite this feature, there are challenges when using portable water-filled barriers (PWFBs) such as large lateral displacements as well as tearing and breakage during impact, especially at higher speeds. In this study, the authors explore the use of composite action to enhance the crashworthiness of PWFBs and enable their use at higher speeds. Initially, we investigated the energy absorption capability of water in PWFB. Then, we considered the composite action of a PWFB with the introduction of a steel frame to evaluate its impact on performance. Findings of the study show that the initial height of impact must be lower than the free surface level of water in a PWFB for the water to provide significant crash energy absorption. In general, impact of a road barrier that is 80% filled is a good estimation. Furthermore, the addition of a composite structure greatly reduces the probability of tearing by decreasing the strain and impact energy transferred to the shell container. This allows the water to remain longer in the barrier to absorb energy via inertial displacement and sloshing response. Information from this research will aid in the design of next generation roadside safety structures aimed to increase safety on modern roadways.
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Most security models for authenticated key exchange (AKE) do not explicitly model the associated certification system, which includes the certification authority (CA) and its behaviour. However, there are several well-known and realistic attacks on AKE protocols which exploit various forms of malicious key registration and which therefore lie outside the scope of these models. We provide the first systematic analysis of AKE security incorporating certification systems (ASICS). We define a family of security models that, in addition to allowing different sets of standard AKE adversary queries, also permit the adversary to register arbitrary bitstrings as keys. For this model family we prove generic results that enable the design and verification of protocols that achieve security even if some keys have been produced maliciously. Our approach is applicable to a wide range of models and protocols; as a concrete illustration of its power, we apply it to the CMQV protocol in the natural strengthening of the eCK model to the ASICS setting.
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Abstract Background: Studies that compare Indigenous Australian and non-Indigenous patients who experience a cardiac event or chest pain are inconclusive about the reasons for the differences in-hospital and survival rates. The advances in diagnostic accuracy, medication and specialised workforce has contributed to a lower case fatality and lengthen survival rates however this is not evident in the Indigenous Australian population. A possible driver contributing to this disparity may be the impact of patient-clinician interface during key interactions during the health care process. Methods/Design: This study will apply an Indigenous framework to describe the interaction between Indigenous patients and clinicians during the continuum of cardiac health care, i.e. from acute admission, secondary and rehabilitative care. Adopting an Indigenous framework is more aligned with Indigenous realities, knowledge, intellects, histories and experiences. A triple layered designed focus group will be employed to discuss patient-clinician engagement. Focus groups will be arranged by geographic clusters i.e. metropolitan and a regional centre. Patient informants will be identified by Indigenous status (i.e. Indigenous and non-Indigenous) and the focus groups will be convened separately. The health care provider focus groups will be convened on an organisational basis i.e. state health providers and Aboriginal Community Controlled Health Services. Yarning will be used as a research method to facilitate discussion. Yarning is in congruence with the oral traditions that are still a reality in day-to-day Indigenous lives. Discussion: This study is nestled in a larger research program that explores the drivers to the disparity of care and health outcomes for Indigenous and non-Indigenous Australians who experience an acute cardiac admission. A focus on health status, risk factors and clinical interventions may camouflage critical issues within a patient-clinician exchange. This approach may provide a way forward to reduce the appalling health disadvantage experienced within the Indigenous Australian communities. Keywords: Patient-clinician engagement, Qualitative, Cardiovascular disease, Focus groups, Indigenous
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Drawing on three case studies of work in the fields of participatory design, interaction design and electronic arts, we reflect on the implications of these studies for haptic interface research. We propose three themes: gestural; emergent; and expressive; as signposts for a program of research into haptic interaction that could point the way towards novel approaches to haptic interaction and move us from optic to haptic ways of seeing.
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The accumulated evidence from more than four decades of education research strongly suggests that parent involvement in schools carries significant benefits for students as well as for the success of schools (e.g., Henderson & Mapp, 2002). Governments in Australia and overseas have supported parent involvement in schools with a range of initiatives while parent groups have indicated a strong desire for expanded school roles that include participation in formal educational processes namely curriculum, pedagogy, and assessment. Research has also signalled the need for teachers to engage parents rather than adopt traditional parent-school involvement practices so that parents can participate as joint educators in their children's schooling alongside teachers (Pushor, 2001). Actually improving the quality of contact and relationships between parents and teachers to enable engagement however remains problematic. Coteaching and cogenerative dialoguing originally emerged as an innovative approach in the context of teaching secondary school science. Coteaching brings together the collective expertise of several individuals to expand learning opportunities for students while cogenerative dialogues refer to sessions in which participants talk, listen, and learn from one another about the process (Roth & Tobin, 2002a). Coteaching and cogenerative dialoguing reportedly benefits students academically and socially while rewarding educators professionally and emotionally through the support and collaboration they receive from fellow coteachers. These benefits ensue because coteaching theoretically positions teachers at one another's elbows, providing new and different understandings about teaching based on first-hand perspectives and shared goals for assisting students to learn. This thesis proposes that coteaching and cogenerative dialoguing may provide a vehicle for improving quality of contact and relationships between parents and teachers. To investigate coteaching and cogenerative dialoguing as a parent-teacher engagement mechanism, interpretive ethnographic case study research was conducted involving two parents and a secondary school teacher. Sociological ideas, namely Bourdieu's (1977) fields, habitus, and capitals, together with multiple dialectical concepts such as agency|structure (Sewell, 1992) and agency|passivity (Roth, 2007b, 2010) were assembled into a conceptual framework to examine parent-teacher relationships by describing and explaining cultural production and identity construction throughout the case study. Video and audio recordings of cogenerative dialogues and cotaught lessons comprised the chief data sources. Data were analysed using qualitative techniques such as discourse and conversation analysis to identify patterns and contradictions (Roth & Tobin, 2002a). The use of quality criteria detailed by Guba and Lincoln (2005) gives credence to the way in which ethical considerations infused the planning and conduct of this research. From the processes of data collection and analyses, three broad assertions were proffered. The findings highlight the significance of using multiple coordinated dialectical concepts for analysing the affordances and challenges of coteaching and cogenerative dialogues that include parents and teachers. Adopting the principles and purposes of coteaching and cogenerative dialoguing promoted trusting respectful relationships that generated an equitable culture. The simultaneous processes and tensions between logistics and ethics (i.e., the logistics|ethics dialectic) were proposed as a new way to conceptualise how power was redistributed among the participants. Knowledge of positive emotional energy and ongoing capital exchange conceived dialectically as the reciprocal interaction among cultural, social, and symbolic capitals (i.e., the dialectical relationship of cultural|social|symbolic capital) showed how coteaching and cogenerative dialoguing facilitated mutual understandings, joint decision-making, and group solidarity. The notion of passivity as the dialectical partner of agency explained how traditional roles and responsibilities were reconfigured and individual and collective agency expanded. Complexities that surfaced when implementing the coteaching and cogenerative dialoguing approach were outweighed by the multiple benefits that accrued for all involved. These benefits included the development of community-relevant and culturally-significant curricula that increased student agency and learning outcomes, heightened parent self-efficacy for participating in and contributing to formal educational processes, and enhanced teacher professionalism. This case study contributes to existing theory, knowledge and practice, and methodology in the research areas of parent-teacher relationships, specifically in secondary schools, and coteaching and cogenerative dialoguing. The study is particularly relevant given the challenges schools and teachers increasingly face to meaningfully connect with parents to better meet the needs of educational stakeholders in times of continual, complex, and rapid societal change.
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Executive Summary This project has commenced an exploration of learning and information experiences in the QUT Cube. Understanding learning in this environment has the potential to inform current implementations and future project development. In this report, we present early findings from the first phase of an investigation into what makes learning possible in the context of a giant interactive multi-media display such as the QUT Cube, which is an award-winning configuration that hosts several projects.
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With this special issue, we draw attention to the growing and diverse field of HCI researchers exploring the interstices of food, technology and everyday practices. This special issue builds on the CHI workshop of the same name (Comber et al., 2012a), where we brought together the community of researchers that take food as a point from which to understand people and design technology. The workshop aimed to ‘to attend to the practical and theoretical difficulties in designing for human–food interactions in everyday life’ identifying four thematic areas of food practices – health and wellbeing; sustainability; food experiences; and alternative food cultures. These practical and theoretical difficulties are evident in the papers that we present here, though the distinction between our four themes, premised by complexities of food practices, is a little less evident. Thus, in the papers that follow we explore how the social, technological, cultural and methodological intertwine in the field of human–food interaction.
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Portable water-filled barriers (PWFB) are roadside structures used to separate moving traffic from work-zones. Numerical PWFB modelling is preferred in the design stages prior to actual testing. This paper aims to study the fluid-structure interaction of PWFB under vehicular impact using several methods. The strategy to treat water as non-structural mass was proposed and the errors were investigated. It was found that water can be treated with the FEA-NSM model for velocities higher than 80kmh-1. However, full SPH/FEA model is still the best treatment for water and necessary for lower impact velocities. The findings in this paper can be used as guidelines for modelling and designing PWFB.