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The purpose of this study is to understand how printing parameters and subsequent annealing impacts porosity and crystallinity of 3D printed polylactic acid (PLA) and how these structural characteristics impact the printed material’s tensile strength in various build directions.

Two experimental studies were used, and samples with a flat vs upright print orientation were compared. The first experiment investigates a scan of printing parameters and annealing times and temperatures above the cold crystallization temperature (T_cc) for PLA. The second experiment investigates annealing above and below T_cc at multiple points over 12 h.

Annealing above T_cc does not significantly impact the porosity but it does increase crystallinity. The increase in crystallinity does not contribute to an increase in strength, suggesting that co-crystallization across the weld does not occur. Atomic force microscopy (AFM) images show that weld interfaces between printed fibers are still visible after annealing above T_cc, confirming the lack of co-crystallization. Annealing below T_cc does not significantly impact porosity or crystallinity. However, there is an increase in tensile strength. AFM images show that annealing below T_cc reduces thermal stresses that form at the interfaces during printing and slightly “heals” the as-printed interface resulting in an increase in tensile strength.

While annealing has been explored in the literature, it is unclear how it affects porosity, crystallinity and thermal stresses in fused filament fabrication PLA and how those factors contribute to mechanical properties. This study explains how co-crystallization across weld interfaces is necessary for crystallinity to increase strength and uses AFM as a technique to observe morphology at the weld.

This chapter is designed for use by commercialization teams evaluating the commercial relevance of a new invention. To be relevant commercially, an invention must create value in one or more markets, which involves solving a problem or satisfying customer needs currently unmet. Unmet needs create market opportunities, and the goal is to identify and evaluate the profitability of these opportunities. The chapter provides an overview of concepts and techniques commonly used in the process. Important distinctions between market and industry concepts are introduced along with common rubrics for categorizing inventions in terms of their technological and market implications. These concepts are then used to discuss the roles of prior experience, lead users, and brainstorming in identifying market opportunities for various types of inventions. Techniques covered include market analysis, Porter’s five forces of industry profitability, analysis of political, economic, social, and technical environments (PEST), and the analysis of strengths, weaknesses, opportunities, and threats (SWOT). The use of these techniques is illustrated for two startup commercialization teams.

Man has been seeking an ideal existence for a very long time. In this existence, justice, love, and peace are no longer words, but actual experiences. How ever, with the American preemptive invasion and occupation of Afghanistan and Iraq and the subsequent prisoner abuse, such an existence seems to be farther and farther away from reality. The purpose of this work is to stop this dangerous trend by promoting justice, love, and peace through a change of the paradigm that is inconsistent with justice, love, and peace. The strong paradigm that created the strong nation like the U.S. and the strong man like George W. Bush have been the culprit, rather than the contributor, of the above three universal ideals. Thus, rather than justice, love, and peace, the strong paradigm resulted in in justice, hatred, and violence. In order to remove these three and related evils, what the world needs in the beginning of the third millenium is the weak paradigm. Through the acceptance of the latter paradigm, the golden mean or middle paradigm can be formulated, which is a synergy of the weak and the strong paradigm. In order to understand properly the meaning of these paradigms, however, some digression appears necessary.

The mobile greasing and servicing plant illustrated has been made for the Anglo Iranian Oil Company's use on the Isle of Grain, Kent, by Equipment Repairs Limited, 19–20 The Viaduct, Alperton, Mddx. It is capable of providing all lubricating servicing over the whole of this very big refinery and it has a number of interesting points in construction and design that might well be adopted on similar but smaller mobile lubrication servicing units.

The purpose of this study was to explore the utility of a virtual reality (VR) classroom experience for improving the capacity of instructional leaders. Specifically, school leaders used VR to build their classroom observation and analysis skills to prepare to have more effective post-observation conversations with teachers. The authors provide insights from multiple data points that highlight the affordances of the virtual setting for improving classroom observation skills.

Drawing on the application of simulations to practice classroom observations, the authors developed a VR experience in which participants tag observable elements of academic discourse using codes from two observation protocols. The protocols identify elements of equitable student access: how teachers call on students and how they design questions. Seventy-five school leaders used the VR platform to observe a classroom scenario and code evidence of equitable classroom access. The authors analyzed data from tagging in the virtual reality scenario and triangulated these data with survey data focused on observation practices from participants' schools. A reflection component is included on the platform to collect these qualitative data.

The study results indicate that the virtual reality platform provides an innovative process for leadership professional development focused on building school leaders' capacity to identify elements of academic discourse during classroom observations. Participants reported that the opportunity to practice classroom observations in a risk-free environment was useful. However, for school leaders to fully transfer the data to using in conversations with teachers, they benefit from leadership coaching.

This study ascertains the potential effectiveness of an advanced technology for enhancing instructional leadership by using evidence-based classrooms observations to drive improvements in teaching practice. Beyond the utility of the virtual reality tool, this study provides a proof of concept for the next generation of instructional leadership through teacher observations with augmented reality.

Student-led project-based teams are widely used by faculty but do we really understand the process that students experience as a result of participating in a team? This study sought to understand the team process by examining leadership practices exhibited by assigned leaders and their team culture. Using a mixed-methods case study design it was found that students perceived team leaders to be strongest in the leadership practice-enable others to act described as fostering collaboration and sharing power and weakest in the leadership practice-encourage the heart described as recognizing individual contributions and celebrating team successes. Two of the teams were identified as a clan culture and the third team was determined to be a market culture. It was recommended that instructors who use teams to enrich learning examine the relationship between specific team cultures and enhanced team performance.

The purpose of this paper is to explore the consequences of a managerial approach to renewal for a union’s behaviour by analysing the UK’s fourth largest trade union – The Union of Shop, Distributive and Allied Workers (USDAW).

The findings draw on in-depth semi-structured interviews with union officials.

The research findings show the significance of a managerialist approach to UDSAW’s renewal strategy and its correlation with existing renewal strategies of organising and partnership. However, this approach was not immune to context, with tensions between agency and articulation challenging the basic concept of managerialism and influencing union behaviour.

The data were collected from a single case with a small sample size.

The authors’ findings suggest that tensions between bureaucracy and democracy will mediate the extent to which managerialist approaches can be used within unions adding support to the strategic choice theory and underlying arguments that unions can influence their fortune. However, institutional and external pressures could see managerialism becoming more prevalent, with oligarchic and bureaucratic forces prevailing, which could be particularly applicable to unions operating in challenging contexts, such as USDAW. The managerialisation of unions has consequences for union officers; with officers facing increasing pressure in their roles to behave as managers with attendant implications for role conflict, identity and motivation.

If managerialism is becoming more prevalent with unions, with oligarchic and bureaucratic forces prevailing, this has potentially wider societal implications, whereby collectivism and worker-led democracy could become scarcer within unions and the workplace, thus irretrievably altering the nature of the employment relationship.

This paper brings together disparate themes in the literature to propose a conceptual framework of three key elements of managerialism: centralised strategies; performance management and the managerialisation of union roles. The authors’ findings demonstrate how there is scope for unions to adopt a hybrid approach to renewal, and to draw upon their internal resources, processes and techniques to implement change, including behavioural change. Consequently, theories and empirical studies of union renewal need to better reflect the complexities of approaches that unions are now adopting and further explore these models within the agency and articulation principles that underpin the nature of unions.

Over the years we have reported prosecutions where the defence has alleged, and with circumstantial support that the presence of a harmful foreign body in food was deliberate through the action of a single disgruntled employee or where the labour relations climate generally has been bad. It makes no difference to the manufacturer's responsibility—the offence is an absolute one—but occasionally courts have allowed it in mitigation. Sometimes, it has been the nature of the extraneous material, e.g. fragments of glass or metal, the like of which did not exist in the factory premises or plant. This may be taken as a symptom of the vandalism of the age, but more recently, two incidents have drawn attention to its dangers and provided a glimpse of the criminal mind which can inflict such injury on employers, and expose innocent consumers, of all ages, to possible harm.

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 old year has gone, leaving its trail of never‐to‐be‐forgotten memories of strife and turbulence, calamity, disaster, and a huge burden of worries for us to face in the New Year. Few if any will not be deeply grateful to see the passing of 1985. Except for the periods of calm there cannot be a year within living memory to equal it in terms of violence, unparalleled in times of “peace”, collosal in terms of soaring social and public expenditure and financial loss, and in disasters in the world beyond the shores of these islands. It would not be an exaggeration to state that the enormous indebtedness which the year has heaped upon the people will never be wiped off, and it has got to be done mainly by those innocent of any misconduct, and their descendants. The unprecedented scale of street and community violence, the looting, thieving and general crime committed behind the screen of it.