949 resultados para special-purpose functionalized conjugated polymers
The use of virtual prototyping to rehearse the sequence of construction work involving mobile cranes
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Purpose – Rehearsing practical site operations is without doubt one of the most effective methods for minimising planning mistakes, because of the learning that takes place during the rehearsal activity. However, real rehearsal is not a practical solution for on-site construction activities, as it not only involves a considerable amount of cost but can also have adverse environmental implications. One approach to overcoming this is by the use of virtual rehearsals. The purpose of this paper is to investigate an approach to simulation of the motion of cranes in order to test the feasibility of associated construction sequencing and generate construction schedules for review and visualisation. Design/methodology/approach – The paper describes a system involving two technologies, virtual prototyping (VP) and four-dimensional (4D) simulation, to assist construction planners in testing the sequence of construction activities when mobile cranes are involved. The system consists of five modules, comprising input, database, equipment, process and output, and is capable of detecting potential collisions. A real-world trial is described in which the system was tested and validated. Findings – Feedback from the planners involved in the trial indicated that they found the system to be useful in its present form and that they would welcome its further development into a fully automated platform for validating construction sequencing decisions. Research limitations/implications – The tool has the potential to provide a cost-effective means of improving construction planning. However, it is limited at present to the specific case of crane movement under special consideration. Originality/value – This paper presents a large-scale, real life case of applying VP technology in planning construction processes and activities.
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The automotive industry has been the focus of digital human modeling (DHM) research and application for many years. In the highly competitive marketplace for personal transportation, the desire to improve the customer’s experience has driven extensive research in both the physical and cognitive interaction between the vehicle and its occupants. Human models provide vehicle designers with tools to view and analyze product interactions before the first prototypes are built, potentially improving the design while reducing cost and development time. The focus of DHM research and applications began with prediction and representation of static postures for purposes of driver workstation layout, including assessments of seat adjustment ranges and exterior vision. Now DHMs are used for seat design and assessment of driver reach and ingress/egress. DHMs and related simulation tools are expanding into the cognitive domain, with computational models of perception and motion, and into the dynamic domain with models of physical responses to ride and vibration. Moreover, DHMs are now widely used to analyze the ergonomics of vehicle assembly tasks. In this case, the analysis aims to determine whether workers can be expected to complete the tasks safely and with good quality. This preface provides a review of the literature to provide context for the nine new papers presented in this special issue.
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The selection of appropriate analogue materials is a central consideration in the design of realistic physical models. We investigate the rheology of highly-filled silicone polymers in order to find materials with a power-law strain-rate softening rheology suitable for modelling rock deformation by dislocation creep and report the rheological properties of the materials as functions of the filler content. The mixtures exhibit strain-rate softening behaviour but with increasing amounts of filler become strain-dependent. For the strain-independent viscous materials, flow laws are presented while for strain-dependent materials the relative importance of strain and strain rate softening/hardening is reported. If the stress or strain rate is above a threshold value some highly-filled silicone polymers may be considered linear visco-elastic (strain independent) and power-law strain-rate softening. The power-law exponent can be raised from 1 to ~3 by using mixtures of high-viscosity silicone and plasticine. However, the need for high shear strain rates to obtain the power-law rheology imposes some restrictions on the usage of such materials for geodynamic modelling. Two simple shear experiments are presented that use Newtonian and power-law strain-rate softening materials. The results demonstrate how materials with power-law rheology result in better strain localization in analogue experiments.
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This chapter examines why policy decision-makers opt for command and control environmental regulation despite the availability of a plethora of market-based instruments which are more efficient and cost-effective. Interestingly, Sri Lanka has adopted a wholly command and control system, during both the pre and post liberalisation economic policies. This chapter first examines the merits and demerits of command and control and market-based approaches and then looks at Sri Lanka’s extensive environmental regulatory framework. The chapter then examines the likely reasons as to why the country has gone down the path of inflexible regulatory measures and has become entrenched in them. The various hypotheses are discussed and empirical evidence is provided. The chapter also discusses the consequences of an environmentally slack economy and policy implications stemming from adopting a wholly regulatory approach. The chapter concludes with a discussion of the main results.
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Introduction: Improving physical and cognitive functioning is a key objective of multi-disciplinary inpatient geriatric rehabilitation. Outcomes relevant to minimum functional ability required for older adults to successfully participate in the community have been reported. However, there has been little investigation reporting outcomes of older inpatients receiving multi-disciplinary rehabilitation being discharged home from geriatric rehabilitation units. This study aims to investigate characteristics and physical and cognitive outcomes of this cohort. Method: The Princess Alexandra Hospital Geriatric and Rehabilitation Unit is the largest rehabilitation unit in Queensland. Multidisciplinary health professionals enter admission and discharge functional and clinical outcomes along with demographic information into a purpose designed database for all patients. Data collected between 2005 and 2011 was analysed using descriptive statistics. Results: During the seven-year period, 4120 patients were admitted for rehabilitation; 2126 (52%) were female, mean age of 74 years (Standard Deviation 14). Primary reasons for admission were for reconditioning post medical illness or surgical admission (n = 1285, 31%), and 30% (n = 1233) admitted for orthopaedic reasons. Of these orthopaedic admissions, 6.6% (n = 82) were for elective surgery, and 46% (n = 565) were for fractured neck-of-femurs. 76% (n = 3130) of patients were discharged home, 13% (n = 552) to residential care facilities and 10% (n = 430) were discharged to an alternative hospital setting or passed away during their admission. Mean length of stay was 44 days (SD 39) Preliminary analysis of FIM outcomes shows a mean motor score of 53 (SD = 19) on admission which significantly improved to 71 (SD = 18) by discharge. There was no change on FIM cognitive score (28 (SD7) vs 29 (SD 6). Conclusion: Geriatric patients have significant functional limitations even on discharge from inpatient rehabilitation; though overall cognition is relatively intact. Orthopaedic conditions and general deconditioning from medical/surgical admissions are the main reasons for admission. The majority of people receiving rehabilitation are discharged home.
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Craving has long been associated with addictive disorders. It has received much attention over the last two decades, partly through the advent of pharmacotherapies that attempt to address it (Jonson, 2008; Yahyavi-Firouz-Abadi & See, 2009). More recently, craving for substances has attained increased prominence, with the inclusion of “Craving or a strong desire or urge” in the draft of DSM-5 (APA, 2012). Studies generally support craving as occurring on a single diagnostic dimension alongside existing dependence criteria (Hasin, et al., 2012; Keyes, et al., 2011). Some (e.g. Keyes, et al., 2011) demonstrate that the addition of craving to DSM-IV alcohol abuse and alcohol dependence criteria contributes novel variance in predicting severity, and improves discrimination above that offered by existing DSM-IV criteria. Within the current volume, the paper by Agrawal et al. confirms that craving strongly loads on a single dimension that also incorporates DSM-IV alcohol dependence criteria. Craving was a relatively severe symptom: It was least often endorsed, and did not exceed 50% endorsement until 6 of the remaining 7 criteria were present...
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Grouping users in social networks is an important process that improves matching and recommendation activities in social networks. The data mining methods of clustering can be used in grouping the users in social networks. However, the existing general purpose clustering algorithms perform poorly on the social network data due to the special nature of users' data in social networks. One main reason is the constraints that need to be considered in grouping users in social networks. Another reason is the need of capturing large amount of information about users which imposes computational complexity to an algorithm. In this paper, we propose a scalable and effective constraint-based clustering algorithm based on a global similarity measure that takes into consideration the users' constraints and their importance in social networks. Each constraint's importance is calculated based on the occurrence of this constraint in the dataset. Performance of the algorithm is demonstrated on a dataset obtained from an online dating website using internal and external evaluation measures. Results show that the proposed algorithm is able to increases the accuracy of matching users in social networks by 10% in comparison to other algorithms.
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A significant gap exists in the Australian research literature on the disproportionate over-representation of minority groups in special education. The aim of this paper is to make a contribution to the research evidence-base by sketching an outline of the issue as it presents in Australia’s largest education system in the state of New South Wales. Findings from this research show that Indigenous students are equally represented in special schools enrolling students with autism, physical, sensory, and intellectual disabilities, but significantly over-represented in special schools enrolling students under the categories of emotional disturbance, behaviour disorder and juvenile detention. Factors that might influence the disproportionate over-representation of Indigenous children and young people are discussed, and based on these observations, some practical implications for policy and practice are provided.
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The management and improvement of business processes are a core topic of the information systems discipline. The persistent demand in corporations within all industry sectors for increased operational efficiency and innovation, an emerging set of established and evaluated methods, tools, and techniques as well as the quickly growing body of academic and professional knowledge are indicative for the standing that Business Process Management (BPM) has nowadays. During the last decades, intensive research has been conducted with respect to the design, implementation, execution, and monitoring of business processes. Comparatively low attention, however, has been paid to questions related to organizational issues such as the adoption, usage, implications, and overall success of BPM approaches, technologies, and initiatives. This research gap motivated us to edit a corresponding special focus issue for the journal BISE/WIRTSCHAFTSINFORMATIK. We are happy that we are able to present a selection of three research papers and a state-of-the-art paper in the scientific section of the issue at hand. As these papers differ in the topics they investigate, the research method they apply, and the theoretical foundations they build on, the diversity within the BPM field becomes evident. The academic papers are complemented by an interview with Phil Gilbert, IBM’s Vice President for Business Process and Decision Management, who reflects on the relationship between business processes and the data flowing through them, the need to establish a process context for decision making, and the calibration of BPM efforts toward executives who see processes as a means to an end, rather than a first-order concept in its own right.
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Production of nanofibrous polyacrylonitrile/calcium carbonate (PAN/CaCO3) nanocomposite web was carried out through solution electrospinning process. Pore generating nanoparticles were leached from the PAN matrices in hydrochloric acid bath with the purpose of producing an ultimate nanoporous structure. The possible interaction between CaCO3 nanoparticles and PAN functional groups was investigated. Atomic absorption method was used to measure the amount of extracted CaCO3 nanoparticles. Morphological observation showed nanofibers of 270–720 nm in diameter containing nanopores of 50–130 nm. Monitoring the governing parameters statistically, it was found that the amount of extraction (ε) of CaCO3was increased when the web surface area (a) was broadened according to a simple scaling law (ε = 3.18 a0.4). The leaching process was maximized in the presence of 5% v/v of acid in the extraction bath and 5 wt % of CaCO3 in the polymer solution. Collateral effects of the extraction time and temperature showed exponential growth within a favorable extremum at 50°C for 72 h. Concentration of dimethylformamide as the solvent had no significant impact on the extraction level.
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Fibrous scaffolds of engineered structures can be chosen as promising porous environments when an approved criterion validates their applicability for a specific medical purpose. For such biomaterials, this paper sought to investigate various structural characteristics in order to determine whether they are appropriate descriptors. A number of poly(3-hydroxybutyrate) scaffolds were electrospun; each of which possessed a distinguished architecture when their material and processing conditions were altered. Subsequent culture of mouse fibroblast cells (L929) was carried out to evaluate the cells viability on each scaffold after their attachment for 24 h and proliferation for 48 and 72 h. The scaffolds’ porosity, pores number, pores size and distribution were quantified and none could establish a relationship with the viability results. Virtual reconstruction of the mats introduced an authentic criterion, “Scaffold Percolative Efficiency” (SPE), with which the above descriptors were addressed collectively. It was hypothesized to be able to quantify the efficacy of fibrous scaffolds by considering the integration of porosity and interconnectivity of the pores. There was a correlation of 80% as a good agreement between the SPE values and the spectrophotometer absorbance of viable cells; a viability of more than 350% in comparison to that of the controls.
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A significant proportion of research in the field of human-computer interaction has been devoted to game design. Yet, a multitude of good ideas and enthusiastic game design initiatives exist, where the games never see the light of day. Unfortunately, the causes of these failures remain often unexplored and unpublished. The challenges faced by researchers and practitioners are particularly complex when designing games for special target groups, such as children, or for a serious purpose. The HCI community would benefit from a discussion on these issues in order to avoid researchers and practitioners to repeat mistakes. We want to learn from projects that started with a promising idea, but failed or faced severe challenges. This workshop will be the first at CHI focusing on 'failed game projects'. In particular, workshop participants are encouraged to discuss issues that typically received little attention in publications and hereby contribute to the discussion on failures in the design, development and evaluation of games for and or with children. As a result, the community will benefit from these insights and lessons-learned, which will enhance the design of future (serious) games with/for children.
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Creative productivity emerges from human interactions (Hartley, 2009, p. 214). In an era when life is lived in rather than with media (Deuze, this issue), this productivity is widely distributed among ephemeral social networks mediated through the internet. Understanding the underlying dynamics of these networks of human interaction is an exciting and challenging task that requires us to come up with new ways of thinking and theorizing. For example, inducting theory from case studies that are designed to show the exceptional dynamics present within single settings can be augmented today by largescale data generation and collections that provide new analytic opportunities to research the diversity and complexity of human interaction. Large-scale data generation and collection is occurring across a wide range of individuals and organisations. This offers a massive field of analysis which internet companies and research labs in particular are keen on exploring. Lazer et al (2009: 721) argue that such analytic potential is transformational for many if not most research fields but that the use of such valuable data must neither remain confined to private companies and government agencies nor to a privileged set of academic researchers whose studies cannot be replicated nor critiqued. In fact, the analytic capacity to have data of such unprecedented scope and scale available not only requires us to analyse what is and could be done with it and by whom (1) but also what it is doing to us, our cultures and societies (2). Part (1) of such analysis is interested in dependencies and their implications. Part (2) of the enquiry embeds part (1) in a larger context that analyses the long-term, complex dynamics of networked human interaction. From the latter perspective we can treat specific phenomena and the methods used to analyse them as moments of evolution.
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In Walter v Buckeridge [No.5] [2012] WASC 495 Le Miere J considered an application by the defendants for special costs orders under the applicable legislation in Western Australia. Aspects of the decision may be of persuasive value in dealing with similar issues under Queensland legislation.
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In this work, ab initio density functional theory (DFT) calculations are performed to study the structural and electronic properties of diazonium reagent functionalized (4, 4) single-walled carbon nanotube (SWCNT). We find the aryl group covalently bonds with SWCNT and prefers to be perpendicular to the side wall of nanotube. It has a rotational barrier of 0.35 eV around the formed aryl-tube bond axis and should be thermodynamically stable at room temperature. Additionally, new peaks appeared around the Fermi energy in the density of state (DOS) due to the weak band dispersion. Increasing of the coverage of the functional group will result in significant upshift of the Fermi level.