Parameter analysis of copper-nickel-tungsten prepared via powder metallurgy process for electrical discharge machining of polycrystalline diamond

Polycrystalline Diamond (PCD) tools have an outstanding wear resistance. The electric conductivity of PCD caused by the conductive binding material (Cobalt) makes it possible to machine PCD tools with EDM. Electrode used in EDM of PCD must have better porosity, electrical and thermal conductivity. Therefore, this research presents the works in production of Cu-Ni-W electrode by powder metallurgy route. Production of powder metallurgy parts involve mixing of the powder with additives or lubricants, compacting the mixture and heating the green compacts in an Argon gas furnace so the particle bond to each other. Two levels of full factorial with six centre points and two replication technique was used to study the influence of main and interaction effects of the powder metallurgy parameter. There were four factors involved in this experiment. Factor A which is Type of Cu-Ni; Type A and Type B was defined as categorical factor. Factor B in which Composition of W; 5 Wt.%, 15 Wt. % and 25 Wt.%, was defined as numerical factor. Factor C which is the Compaction load; 7, 8 and 9 tonne and Factor D which is Sintering temperature; 635 ℃, 685 ℃ and 735 ℃ were also defined as numerical factor. Optical Microscope, Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) was used to analysed the microstructure and surface morphology of Cu-Ni-W electrode. The best parameter combination to produced better porosity, electrical and thermal conductivity for both Type A and Type B was 5 Wt.% of W, compaction load at 9 tonne and sintering temperature at 735℃. The best response for Type A is 12.65% of porosity, 14.40 IACS% of electrical conductivity and 413.26 W/m.℃ of thermal conductivity. While that, the best response for Type B were 9.36% of porosity, 16.66 IACS% of electrical conductivity and 345.21W/m.℃ of thermal conductivity. From the calculation of Maxwell’s Equation, Type A and Type B had the highest electrical conductivity of 58.48 IACS% and 77.35 IACS% respectively at W content of 5Wt.%. Type A and Type B also had the highest thermal conductivity of 369.86 W/m.℃ and 310.24 W/m.℃ respectively at W content of 5 Wt.%. Besides that, thermal conductivity also increased with the temperature increased until 450℃

Developing a creative foreign language reader: in search of a theoretical approach and didactic techniques

The paper discusses different conceptions of creativity in relation to reading in a FL. It looks at psycholinguistic approaches that view creativity as a mentalistic individual creative thought. Further, it discusses sociocultural theories that take in account social, cultural and environmental factors. Special attention is given to a critical aspect of creativity. In the next section, the author looks at how psycholinguistic and sociolinguistic approaches view literacy and what they can offer for both FL/L2 research and pedagogy. The presentation argues for viewing the FL/L2 reading situation as an interaction of cognitive and social factors and emphases the importance of developing skills to critique texts. It suggests a set of tasks to be applied in a FL classroom aiming at improving creative reading skills

Sources, topics and use of knowledge by coaches

In recent years, the value of social learning approaches as part of the design and delivery of formalised coach development initiatives has gained credence in the literature. However, insight is currently lacking into the fundamental social dimensions that underpin coach learning. Accordingly, this study aimed to explore coaches’ perceptions of their actual and preferred methods of acquiring new coaching knowledge, the types of knowledge they currently acquire and/or desire, and their application of new knowledge. Responses to an online survey, completed by practicing coaches (N = 320) in a range of sports and contexts, were analysed descriptively and inductively. Results revealed that coaches’ preferred, and mostly acquired, coaching knowledge from informal learning activities, especially when these permitted social interaction. Notably, however, formal coach education courses were also reported relatively frequently as a source of recent knowledge acquisition. Nevertheless, critical justification for and application of, acquired knowledge was largely absent. Based on the findings, we suggest that, before social learning activities such as mentoring schemes and communities of practice are placed at the centre of formalised coach development provision, coach educators must put in place the support structures to better enable coaches to recognise and deal with the potentially mixed influences of the social milieu on coach learning, aiming to ensure that their informal development is sufficiently open-minded, reflective and critical

Critical legal reading: The elements, strategies and dispositions needed to master this essential skill

Alex Steel, Kate Galloway, Mary Heath, Natalie Skead, Mark Israel, Anne Hewit

Norms and Law: Putting the Horse Before the Cart

Law and society scholars have long been fascinated with the interplay of formal legal and informal extralegal procedures. Unfortunately, the fascination has been accompanied by imprecision, and scholars have conceptually conflated two very different mechanisms that extralegally resolve disputes. One set of mechanisms might be described as the shadow of the law, made famous by seminal works by Professors Stewart Macaulay and Marc Galanter, in which social coercion and custom have force because formal legal rights are credible and reasonably defined. The other set of mechanisms, recently explored by economic historians and legal institutionalists, might be described as order without law, borrowing from Professor Robert Ellickson\u27s famous work.1 In this second mechanism, extralegal mechanisms—whether organized shunning, violence, or social disdain—replace legal coercion to bring social order and are an alternative to, not an extension of, formal legal sanctions. One victim of conflating these mechanisms has been our understanding of industry-wide systems of private law and private adjudication, or private legal systems. Recent examinations of private legal systems have chiefly understood those systems as efforts to economize on litigation and dispute-resolution costs, but private legal systems are better understood as mechanisms that economize on enforcement costs. This is not a small mischaracterization. Instead, it reveals a deep misunderstanding of when and why private enforcement systems arise in a modern economy. This Essay provides a taxonomy for the various mechanisms of private ordering. These assorted mechanisms, despite their important differences, have been conflated in large part because there has been a poor understanding of the particular institutional efficiencies and costs of the alternative systems. Specifically, enforcement costs have often been inadequately distinguished from procedural or disputeresolution costs, and this imprecision has produced theories that inaccurately predict when private ordering will thrive and when the costs of private ordering overwhelm corresponding efficiencies. The implications for institutional theory are significant, as confusion in the literature has led to overappreciation of private ordering, underappreciation of social institutions, and Panglossian attitudes toward both lawlessness and legal development

Towards an Indexical Model of Situated Language Comprehension for Cognitive Agents in Physical Worlds

We propose a computational model of situated language comprehension based on the Indexical Hypothesis that generates meaning representations by translating amodal linguistic symbols to modal representations of beliefs, knowledge, and experience external to the linguistic system. This Indexical Model incorporates multiple information sources, including perceptions, domain knowledge, and short-term and long-term experiences during comprehension. We show that exploiting diverse information sources can alleviate ambiguities that arise from contextual use of underspecific referring expressions and unexpressed argument alternations of verbs. The model is being used to support linguistic interactions in Rosie, an agent implemented in Soar that learns from instruction.Comment: Advances in Cognitive Systems 3 (2014

Local Government Action and Antitrust Policy: An Economic Analysis

At least partly as a result of the Supreme Court decision in Community Communications Co. v. City of Boulder, cities are facing antitrust challenges to their rights to franchise cable television systems. Other municipal activities have been similarly challenged. The prospect of costly and uncertain antitrust litigation challenging local government actions will restrict the scope and extent of local regulatory activity. Such restrictions could, in turn, preempt city residents\u27 ability to choose, through their elected representatives, the goods and services they prefer. This Article proposes that as a mater of policy the burden of proving a municipal antitrust violation should be on those who seek to restrict municipal action. This Article discusses the merits behind the general case for municipal antitrust immunity and the specific circumstances in which cities might face liability under antitrust laws. Further, this Article sets out three criteria by which the potential for adverse effects of a city\u27s action may be determined, then assesses the leading state action cases using these criteria. Finally, this Article concludes by describing the appropriate policies for dealing with potentially inefficient city actions and makes specific recommendations consistent with the current case law