981 resultados para Liana cutting


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Energy harvesting from ambient vibration is a promising field, especially for applications in larger infrastructures such as bridges. These structures are more frequently monitored for damage detection because of their extended life, increased traffic load and environmental deterioration. In this regard, the possibility of sourcing the power necessary for the sensors from devices embedded in the structure, thus cutting the cost due to the management of battery replacing over the lifespan of the structure, is particularly attracting. Among others, piezoelectric devices have proven to be especially effective and easy to apply since they can be bonded to existing host structure. For these devices the energy harvesting capacity is achieved directly from the variation in the strain conditions from the surface of the structure. However these systems need to undergo significant research for optimisation of their harvesting capacity and for assessing the feasibility of application to various ranges of bridge span and load. In this regard scaled bridge prototypes can be effectively used not only to assess numerical models and studies in an inexpensive and repeatable way but also to test the electronic devices under realistic field conditions. In this paper the theory of physical similitude is applied to the design of bridge beams with embedded energy harvesting systems and health monitoring sensors. It will show both how bridge beams can be scaled in such a way to apply and test energy harvesting systems and 2) how experimental data from existing bridges can be applied to prototypes in a laboratory environment. The study will be used for assessing the reliability of the system over a train bridge case study undergoing a set load cycles and induced localised damage.

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Polymorphism of crystalline drugs is a common phenomenon. However, the number of reported polymorphic cocrystals is very limited. In this work, the synthesis and solid-state characterization of a polymorphic cocrystal composed of sulfadimidine (SD) and 4-aminosalicylic acid (4-ASA) is reported for the first time. By liquid-assisted milling, the SD:4-ASA 1:1 form I cocrystal, the structure of which has been previously reported, was formed. By spray drying, a new polymorphic form (form II) of the SD:4-ASA 1:1 cocrystal was discovered which could also be obtained by solvent evaporation from ethanol and acetone. Structure determination of the form II cocrystal was calculated using high-resolution X-ray powder diffraction. The solubility of the SD:4-ASA 1:1 cocrystal was dependent on the pH and predicted by a model established for a two amphoteric component cocrystal. The form I cocrystal was found to be thermodynamically more stable in aqueous solution than form II, which showed transformation to form I. Dissolution studies revealed that the dissolution rate of SD from both cocrystals was enhanced when compared with a physical equimolar mixture and pure SD.

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In this study, 39 sets of hard turning (HT) experimental trials were performed on a Mori-Seiki SL-25Y (4-axis) computer numerical controlled (CNC) lathe to study the effect of cutting parameters in influencing the machined surface roughness. In all the trials, AISI 4340 steel workpiece (hardened up to 69 HRC) was machined with a commercially available CBN insert (Warren Tooling Limited, UK) under dry conditions. The surface topography of the machined samples was examined by using a white light interferometer and a reconfirmation of measurement was done using a Form Talysurf. The machining outcome was used as an input to develop various regression models to predict the average machined surface roughness on this material. Three regression models - Multiple regression, Random Forest, and Quantile regression were applied to the experimental outcomes. To the best of the authors’ knowledge, this paper is the first to apply Random Forest or Quantile regression techniques to the machining domain. The performance of these models was compared to each other to ascertain how feed, depth of cut, and spindle speed affect surface roughness and finally to obtain a mathematical equation correlating these variables. It was concluded that the random forest regression model is a superior choice over multiple regression models for prediction of surface roughness during machining of AISI 4340 steel (69 HRC).

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Continuous research endeavors on hard turning (HT), both on machine tools and cutting tools, have made the previously reported daunting limits easily attainable in the modern scenario. This presents an opportunity for a systematic investigation on finding the current attainable limits of hard turning using a CNC turret lathe. Accordingly, this study aims to contribute to the existing literature by providing the latest experimental results of hard turning of AISI 4340 steel (69 HRC) using a CBN cutting tool. An orthogonal array was developed using a set of judiciously chosen cutting parameters. Subsequently, the longitudinal turning trials were carried out in accordance with a well-designed full factorial-based Taguchi matrix. The speculation indeed proved correct as a mirror finished optical quality machined surface (an average surface roughness value of 45 nm) was achieved by the conventional cutting method. Furthermore, Signal-to-noise (S/N) ratio analysis, Analysis of variance (ANOVA), and Multiple regression analysis were carried out on the experimental datasets to assert the dominance of each machining variable in dictating the machined surface roughness and to optimize the machining parameters. One of the key findings was that when feed rate during hard turning approaches very low (about 0.02mm/rev), it could alone be most significant (99.16%) parameter in influencing the machined surface roughness (Ra). This has, however also been shown that low feed rate results in high tool wear, so the selection of machining parameters for carrying out hard turning must be governed by a trade-off between the cost and quality considerations.

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Vegetables of the Apiaceae plant family such as carrots, parsnip, celery and parsley,contain in minor quantities, a group of bioactive aliphatic C17-polyacetylenes (falcarinol,falcarindiol, falcarindiol-3- acetate). Recent studies have highlighted important biologicalfunctions in vitro and in vivo (animal studies) although the beneficial effect in humannutrition attributable to an increased in polyacetylenes diet are yet to be confirmed(Lund, 1990).Carrots not only contain relatively high polyacetylene content but also form a significantpart of many countries dietary habits. Carrots are also present in some ready-to-eat foodssuch as chilled freshly prepared salads, as part of the increasingly popular minimallyprocessed foods. Whereas the effect of conventional processing (boiling, vacuum processing) on the levels of polyacetylenes has been relatively well studied, the effect of minimal mechanical operations such as “peeling”, “mechanical cutting” and “chlorine washing” remains unknown.

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This book represents a critical examination of key aspects of crime and criminal justice in Northern Ireland which will have resonance elsewhere. It considers the core aspects of criminal justice policymaking in Northern Ireland which are central to the process of post-conflict transition, including reform of policing, judicial decision-making and correctional services such as probation and prisons. It examines contemporary trends in criminal justice in Northern Ireland as related to various dimensions of crime relating to female offenders, young offenders, sexual and violent offenders, race and criminal justice, community safety and restorative justice. The book also considers the extent to which crime and criminal justice issues in Northern Ireland are being affected by the broader processes of ‘policy transfer’, globalisation and transnationalism and the extent to which criminal justice in Northern Ireland is divergent from the other jurisdictions in the United Kingdom. Written by leading international authorities in the field, the book offers a snapshot of the cutting edge of critical thinking in criminal justice practice and transitional justice contexts.

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Complex collaboration in rapidly changing business environments create challenges for management capability in Utility Horizontal Supply Chains (UHSCs) involving the deploying and evolving of performance measures. The aim of the study is twofold. First, there is a need to explore how management capability can be developed and used to deploy and evolve Performance Measurement (PM), both across a UHSC and within its constituent organisations, drawing upon a theoretical nexus of Dynamic Capability (DC) theory and complementary Goal Theory. Second, to make a contribution to knowledge by empirically building theory using these constructs to show the management motivations and behaviours within PM-based DCs. The methodology uses an interpretive theory building, multiple case based approach (n=3) as part of a USHC. The data collection methods include, interviews (n=54), focus groups (n=10), document analysis and participant observation (reflective learning logs) over a five-year period giving longitudinal data. The empirical findings lead to the development of a conceptual framework showing that management capabilities in driving PM deployment and evolution can be represented as multilevel renewal and incremental Dynamic Capabilities, which can be further understood in terms of motivation and behaviour by Goal-Theoretic constructs. In addition three interrelated cross cutting themes of management capabilities in consensus building, goal setting and resource change were identified. These management capabilities require carefully planned development and nurturing within the UHSC. 

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he Science of Lost Medieval Gaelic Graveyard tells the story of the discovery in 2003 of a graveyard and the foundations of a small forgotten stone church at Ballyhanna, in Ballyshannon, Co. Donegal, as part of the N15 Bundoran–Ballyshannon Bypass archaeological works. This led to the excavation of one of the largest collections of medieval burials ever undertaken on this island. Over 1,200 individuals were excavated from the site at Ballyhanna during the winter of 2003–4, representing 1,000 years of burial through the entire Irish medieval period. The discovery led to the establishment of a cross-border research collaboration—the Ballyhanna Research Project—between Queen’s University Belfast and the Institute of Technology, Sligo, which has brought to life this lost Gaelic graveyard.

This book shows how cutting-edge scientific research may aid our understanding and interpretation of archaeology and reveal new insights into past societies. For example, the use of ancient DNA analysis represented the first biomolecular archaeological evaluation of a medieval population to date and provided evidence that cystic fibrosis was much less prevalent in the medieval period than today. The Science of Lost Medieval Gaelic Graveyard is about a community who lived in Gaelic Ireland, about their lifestyles, health and diet. It tells us of their deaths and of their burial traditions, and through examining all of these aspects, it reveals the ebb and flow of their lives.

The book is accompanied by a CD-ROM which includes supplementary information from the Ballyhanna Research Project and the original excavation and survey reports for all of the archaeological sites on the N15 Bundoran–Ballyshannon Bypass.

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Within the last decade, due to significant improvements in the spatial and temporal resolution of chromospheric data, magneto hydrodynamic (MHD)wave studies in this fascinating region of the Sun's atmosphere have risen to the forefront of solar physics research. In this review we begin by reviewing the challenges and debates that have manifested in relation to MHD wave mode identification in fine-scale chromosphericmagnetic structures, including spicules, fibrils and mottles. Next we goon to discuss how the process of accurately identifying MHD wave modes also has a crucial role to play in estimating their wave energy flux.This is of cardinal importance for estimating what the possible contribution of MHD waves is to solar atmospheric heating. Finally, we detail how such advances in chromospheric MHD wave studies have also allowed us, for the first time, to implement cutting-edge magneto seismological techniques that provide new insight into the sub-resolution plasma structuring of the lower solar atmosphere.

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Scholars and practitioners working in ‘transitional justice’ are concerned with remedies of accountability and redress in the aftermath of conflict and state repression. Transitional justice, it is argued, provides recognition of the rights of victims, promotes civic trust, and strengthens the democratic rule of law. As serious scholarship flourishes around this critical concept as never before, this new collection from Routledge meets the need for an authoritative reference work to map a vibrant site of research and reflection. In four volumes, Transitional Justice brings together foundational and the best and most influential cutting-edge materials, including key works produced before the term ‘transitional justice’ gained wide currency but which anticipate approaches now included under that rubric.

The collection covers themes such as: truth and history; acknowledgement, reconciliation, and forgiveness; retribution, restorative justice and reparations; and democracy, state-building, identity, and civil society

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Scholars and practitioners working in ‘transitional justice’ are concerned with remedies of accountability and redress in the aftermath of conflict and state repression. Transitional justice, it is argued, provides recognition of the rights of victims, promotes civic trust, and strengthens the democratic rule of law. As serious scholarship flourishes around this critical concept as never before, this new collection from Routledge meets the need for an authoritative reference work to map a vibrant site of research and reflection. In four volumes, Transitional Justice brings together foundational and the best and most influential cutting-edge materials, including key works produced before the term ‘transitional justice’ gained wide currency but which anticipate approaches now included under that rubric.

The collection covers themes such as: truth and history; acknowledgement, reconciliation, and forgiveness; retribution, restorative justice and reparations; and democracy, state-building, identity, and civil society

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The use of nonviolent action is on the rise. From the Occupy Movement to the Arab Spring and mass protests on the streets of Brazil, activists across the world are increasingly using unarmed tactics to challenge oppressive, corrupt and unjust systems. But what exactly do we mean by nonviolence? How is it deployed and to what effect? Do nonviolent campaigns with political motivations differ from those driven by primarily economic concerns? What are the limits and opportunities for activists engaging in nonviolent action today? Is the growing number of nonviolence protests indicative of a new type of twenty-first century struggle or is it simply a passing trend?
Understanding Nonviolence: Contours and Contexts is the first book to offer a comprehensive introduction to nonviolence in theory and practice. Combining insightful analysis of key theoretical debates with fresh perspectives on contemporary and historical case studies, it explores the varied approaches, aims, and trajectories of nonviolent campaigns from Gandhi to the present day. With cutting-edge contributions from leading scholars and practitioners in the field, this accessible and lively book will be essential reading for activists, students and teachers of contentious politics, international security, and peace and conflict studies.

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In this work, the impact of conventional drilling and helical milling processes on the fatigue response Ti-6Al-4V (grade 5 titanium alloy) has been presented. Results show that the work pieces produced by helical milling has a 119% longer fatigue life compared with the drilled pieces under dry machining condition, and a 96% longer fatigue life for helical milled piece under lubricated condition. The use of cutting fluid has led to longer fatigue lives – 15% longer for drilling and 3% longer for helical milling. Other results such as the machined surface roughness, alloy surface and sub-surface microstructures have also been studied in details.