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To determine static friction coefficients between rapid tooled materials and thermoplastic materials to better understand ejection force requirements for the injection molding process using rapid‐tooled mold inserts.

Static coefficients of friction were determined for semi‐crystalline high‐density polyethylene (HDPE) and amorphous high‐impact polystyrene (HIPS) against two rapid tooling materials, sintered steel with bronze (LaserForm ST‐100) and stereolithography resin (SL5170), and against P‐20 mold steel. Friction tests, using the ASTM D 1894 standard, were run for all material pairs at room temperature, at typical part ejection temperatures, and at ejection temperatures preceded by processing temperatures. The tests at high temperature were designed to simulate injection molding process conditions.

The friction coefficients for HDPE were similar on P‐20 Steel, LaserForm ST‐100, and SL5170 Resin at all temperature conditions. The HIPS coefficients, however, varied significantly among tooling materials in heated tests. Both polymers showed highest coefficients on SL5170 Resin at all temperature conditions. Friction coefficients were especially high for HIPS on the SL5170 Resin tooling material.

Applications of these findings must consider that elevated temperature tests more closely simulated the injection‐molding environment, but did not exactly duplicate it.

The data obtained from these tests allow for more accurate determination of friction conditions and ejection forces, which can improve future design of injection molds using rapid tooling technologies.

This work provides previously unavailable friction data for two common thermoplastics against two rapid tooling materials and one steel tooling material, and under conditions that more closely simulate the injection‐molding environment.

This chapter provides a comprehensive review of research and developments relating to the use of Web 2.0 technologies in education. As opposed to early educational uses of the Internet involving publication of static information on web pages, Web 2.0 tools offer a host of opportunities for educators to provide more interactive, collaborative, and creative online learning experiences for students. The chapter starts by defining Web 2.0 tools in terms of their ability to facilitate online creation, editing, and sharing of web content. A typology of Web 2.0 technologies is presented to illustrate the wide variety of tools at teachers’ disposal. Educational uses of Web 2.0 technologies such as wikis, blogs, and microblogging are explored, in order to showcase the variety of designs that can be utilized. Based on a review of the research literature the educational benefits of using Web 2.0 technologies are outlined, including their ability to facilitate communication, collaborative knowledge building, student-centered activity, and vicarious learning. Similarly, issues surrounding the use of Web 2.0 tools are distilled from the literature and discussed, such as the possibility of technical problems, collaboration difficulties, and plagiarism. Two case studies involving the use Web 2.0 tools to support personalized learning and small group collaboration are detailed to exemplify design possibilities in greater detail. Finally, design recommendations for learning and teaching using Web 2.0 are presented, again based on findings from the research literature.

Investigates the differences in protocols between arbitral tribunals and courts, with particular emphasis on US, Greek and English law. Gives examples of each country and its way of using the law in specific circumstances, and shows the variations therein. Sums up that arbitration is much the better way to gok as it avoids delays and expenses, plus the vexation/frustration of normal litigation. Concludes that the US and Greek constitutions and common law tradition in England appear to allow involved parties to choose their own judge, who can thus be an arbitrator. Discusses e‐commerce and speculates on this for the future.

Today, eXtensible Markup Language (XML) is fast emerging as the dominant standard for storing, describing, representing and interchanging data among various enterprises systems and databases in the context of complex web enterprises information systems (EIS). Conversely, for web EIS (such as ecommerce and portals) to be successful, it is important to apply a high level, model driven solutions and meta‐data vocabularies to design and implementation techniques that are capable of handling heterogonous schemas and documents. For this, we need a methodology that provides a higher level of abstraction of the domain in question with rigorously defined standards that are to be more widely understood by all stakeholders of the system. To‐date, UML has proven itself as the language of choice for modeling EIS using OO techniques. With the introduction of XML Schema, which provides rich facilities for constraining and defining enterprise XML content, the combination of UML and XML technologies provide a good platform (and the flexibility) for modeling, designing and representing complex enterprise contents for building successful EIS. In this paper, we show how a layered view model coupled with a proven user interface analysis framework (WUiAM) is utilized in providing architectural construct and abstract website model (called eXtensible Web, xWeb), to model, design and implement simple, usercentred, collaborative websites at varying levels of abstraction. The uniqueness xWeb is that the model data (web user interface definitions, website data descriptions and constraints) and the web content are captured and represented at the conceptual level using views (one model) and can be deployed (multiple platform specific models) using one or more implementation models.

With an extensive range of information available at the swipe of a finger, the smartphone has become a ubiquitous tool for augmenting conversation. Users of English as a lingua franca (ELF) often rely on such technology to help establish friendships by using them to sustain intersubjectivity. But how do they manage the multiple involvements this entails, such as participating in current talk while searching for linguistic items?

This study employs multimodal Conversation Analysis to undertake a detailed account of the way two young people, a Japanese male (22) and an Indonesian male (16) incorporate smartphones into their lingua franca English interaction. The analysis is based on naturally occurring conversations video-recorded by the Japanese participant, while both boys were living with an American homestay family.

The analysis explores the role of the smartphone in forward-oriented repair, including how the interactants, look up unfamiliar words, delay turn progressivity to fit those words into the turn-in-progress, and use images to accompany an unclear term. Speakers also occasionally abandon a look-up in order to reformulate the turn without the smartphone, relying instead on their own interactional competence.

The study offers insight into the way young people use smartphones as an affordance to manage and repair aspects of their L2 talk, enabling them to enhance their current interactional competence by drawing on the vast range of semiotic resources the phone possesses. Ensuring understanding is essential for developing and maintaining friendships, and for this particular peer culture of lingua franca English speakers, smartphones are a key tool for accomplishing that. As such, the study will be of interest to researchers and educators in the fields of both technology and interaction.

SO much controversy has raged around the subject of newsrooms in the past two years, that librarians are, as a rule, utterly tired of it, and the appearance of still another article upon the subject is not calculated to tone down the general spirit of vexation. It requires no little courage to appear in the arena in this year of Grace, openly championing those departments of our institutions which were originally intended to convey the news of the day in the broadest manner.

The purpose of this paper is to both determine the effects of the nonlinearity on the wave dynamics and assess the temporal and spatial accuracy of five finite difference methods for the solution of the inviscid generalized regularized long-wave (GRLW) equation subject to initial Gaussian conditions.

Two implicit second- and fourth-order accurate finite difference methods and three Runge-Kutta procedures are introduced. The methods employ a new dependent variable which contains the wave amplitude and its second-order spatial derivative. Numerical experiments are reported for several temporal and spatial step sizes in order to assess their accuracy and the preservation of the first two invariants of the inviscid GRLW equation as functions of the spatial and temporal orders of accuracy, and thus determine the conditions under which grid-independent results are obtained.

It has been found that the steepening of the wave increase as the nonlinearity exponent is increased and that the accuracy of the fourth-order Runge-Kutta method is comparable to that of a second-order implicit procedure for time steps smaller than 100th, and that only the fourth-order compact method is almost grid-independent if the time step is on the order of 1,000th and more than 5,000 grid points are used, because of the initial steepening of the initial profile, wave breakup and solitary wave propagation.

This is the first study where an accuracy assessment of wave breakup of the inviscid GRLW equation subject to initial Gaussian conditions is reported.

The purpose of this research is to investigate how bridging and bonding social capital relate to career success among career women in a patriarchal African society. Further, the intervening role of self-esteem in the association between social capital and career success was examined.

Structured questionnaire was used to collect data from 488 Nigerian career women in management cadres in both private and public sectors. Partial least squares structural equation modeling was applied in testing the proposed hypotheses.

The outcomes show that bridging social capital has a significant positive relationship with subjective and objective career success. Conversely, bonding social capital has no significant positive relationship with subjective and objective career success. Further analyses show that self-esteem only partially mediates the association between bridging social capital and career success while an insignificant intervening effect of self-esteem on the association between bonding social capital and career success was found.

The findings suggest the need for organisations to stimulate a friendly work environment that has a zero-tolerance culture for workplace discrimination against women. This will enable the women to relate with people in the workplace irrespective of gender or cadre to generate more bridging social capital to achieve greater career success.

The study extends social capital and career success research to career women in a patriarchal African context as a response to the call for context-specific career research in non-western countries particularly Africa. Second, the study provides empirical evidence that African career woman with bridging social capital can achieve career success irrespective of their self-esteem level amid patriarchal discrimination.

Using the philosophical lenses of revisionist ontology and the politics of personhood, this paper explores the notion of Black Founders of the United States. I introduce the concept critical intellectual agency to argue that Black Founders brought unique contributions to the American experience. Their efforts were twofold. First, Black Founders established separate Black institutions that would become staples in Black communities after emancipation. Second, Black Founders challenged the supposed egalitarian beliefs of White Founders through media outlets. To illustrate, I focus on one Black Founder, Benjamin Banneker and his letter to Thomas Jefferson to illustrate how Black Founders philosophically responded and challenged White Founders prejudicial beliefs about Blackness. This paper seeks to challenge social studies teachers’ curricular and pedagogical approaches to Black Americans during the colonial period by providing a heuristics and language to explore the voices of Black Americans in U.S. history.