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Ultrasonic additive manufacturing (UAM) is a fabrication technology based on ultrasonic metal welding. As a solid-state process, temperatures during UAM fabrication reach a fraction of the melting temperatures of the participating metals. UAM parts can become mechanically compliant during fabrication, which negatively influences the ability of the welder to produce consistent welds. This study aims to evaluate the effect of weld power on weld quality throughout a UAM build, and develop a new power-compensation approach to achieve homogeneous weld quality.

The study utilizes mechanical push-pin testing as a metric of delamination resistance, as well as focused ion beam and scanning electron microscopy to analyze the interface microstructure of UAM parts.

Weld power was found to negatively affect mechanical properties and microstructure. By keeping weld power constant, the delamination energy of UAM coupons was increased 22 per cent along with a consistent grain structure. As a result, to ensure constant properties throughout UAM component construction, maintaining weld power is preferable over the conventional strategy based on amplitude control.

Further characterization could be conducted to evaluate the power control strategy on other material combinations, though this study strongly suggests that the proposed approach should work regardless of the metals being welded.

The proposed power control strategy can be implemented by monitoring and controlling the electrical power supplied to the welder. As such, no additional hardware is required, making the approach both useful and straightforward to implement.

This research paper is the first to recognize and address the negative effect of build compliance on weld power input in UAM. This is also the first paper to correlate measured weld power with the microstructure and mechanical properties of UAM parts.

Despite the focal position of school principals in Australian education, there exist hardly any data on the work that they actually do. This study reports on continuous observations — for three weeks each — of the principals of a State High School, an Independent College and a Catholic College in Melbourne. The variables of their work during the school day were recorded by the researcher, who attempted non‐participant observation, and the principals kept a diary of their “after‐hours” work. The content and characteristics of their work are described with the Findings expressed in a set of propositions about the principalship.

The full ‘storytelling’ paper was written in 1978 and was influential in its time. It is reprinted here, introduced by an Author's reflection on it in 2014. The chapter describes the author’s early disenchantment with traditional approaches to educational research.

He regards educational research as, at best, a misnomer, since little of it is preceded by a search. Entitled educational researchers often fancy themselves as scientists at work. But those whom they attempt to describe are often artists at work. Statistical methodologies enable educational researchers to measure something, but their measurements can neither capture nor explain splendid teaching.

Since such a tiny fraction of what is published in educational research journals influences school practitioners, professional researchers should risk trying alternative approaches to uncovering what is going on in schools.

Story telling is posited as a possible key to producing insights that inform and ultimately improve educational practice. It advocates openness to broad inquiry into the culture of the educational setting.

The experimental parliamentary subsidy on knights' fees and freehold incomes from lands and rents of 1431 was the only English direct lay tax of the Middle Ages which broke down. As such, this subsidy has a clear historiographical significance, yet previous scholars have tended to overlook it on the grounds that parliament's annulment act of 1432 mandated the destruction of all fiscal administrative evidence. Many county assessments from 1431–1432 do, however, survive and are examined for the first time in this article as part of a detailed assessment of the fiscal and administrative context of the knights' fees and incomes tax. This impost constituted a royal response to excess expenditures associated with Henry VI's “Coronation Expedition” of 1429–1431, the scale of which marked a decisive break from the fiscal-military strategy of the 1420s. Widespread confusion regarding whether taxpayers ought to pay the feudal or the non-feudal component of the 1431 subsidy characterized its botched administration. Industrial scale under-assessment, moreover, emerged as a serious problem. Officials' attempts to provide a measure of fiscal compensation by unlawfully double-assessing many taxpayers served to increase administrative confusion and resulted in parliament's annulment act of 1432. This had serious consequences for the crown's finances, since the regime was saddled with budgetary and debt problems which would ultimately undermine the solvency of the Lancastrian state.

Problems of competence grow out of institutional culture and from the way these institutions shape the profession and its members. Toward that end, this chapter is organized around three general considerations. First, we discuss some general issues about leader quality. Second, the present shape of the leadership corps in higher education will be discussed. Finally, we introduce several 21st century leadership core competencies (Brooks & Normore, 2009) for consideration to hiring personnel so they do not repeatedly select and promote unqualified leaders who stifle creativity and encourage conformity.

The case compares two U.S. Department of Defense (DoD) programs from the 1970s and 1980s: (1) “stealth” combat aircraft, capable of evading detection or engagement by anti-aircraft systems, and (2) precision attack of hardened ground vehicles from “standoff” distances, i.e., far behind the battle lines. Conceived at roughly the same time, motivated by the same strategic challenge, and initially driven by the same DoD organization, stealth combat aircraft progressed from idea to deployment in less than eight years---an astounding pace for a complex military system---while a demonstrated system for standoff precision strike against mobile ground targets was not fully implemented. The case highlights the critical role of the Defense Advanced Research Projects Agency (DARPA), part of the DoD, regarded as one of the most innovative entities in the U.S. federal government.

The case highlights factors that facilitate rapid, successful implementation of radically innovative or disruptive concepts. Students are introduced to the organizational realities facing such projects, including issues of strategic clarity, interdepartmental competition and cooperation, executive leadership, and timing. Comparing the differences in implementation of the two programs in the case reveals issues relevant to any large organization seeking to bring innovative concepts to fruition.

This paper aims to comprehensively review ultrasonic additive manufacturing (UAM) process history, technology advancements, application areas and research areas. UAM, a hybrid 3D metal printing technology, uses ultrasonic energy to produce metallurgical bonds between layers of metal foils near room temperature. No melting occurs in the process – it is a solid-state 3D metal printing technology.

The paper is formatted chronologically to help readers better distinguish advancements and changes in the UAM process through the years. Contributions and advancements are summarized by academic or research institution following this chronological format.

This paper summarizes key physics of the process, characterization methods, mechanical properties, past and active research areas, process limitations and application areas.

This paper reviews the UAM process for the first time.

The (A) case describes the evolution between 1999 and 2005 of an unusual innovation team within the office of the chief information officer at oil and gas giant BP. This team helped business units conceive, develop, and implement novel, value-added applications for emerging information technologies. The team leader, vice president and chief technology officer Phiroz Darukhanavala (“Daru”), eschewed a large group and venture budget in favor of a small, lean team intimately engaged with BP's business units. The case describes several mechanisms created by the CTO office during its early evolution: “Blue Chalk” events that expanded executives' appreciation of emerging technology capabilities, a network of relationships through which emerging technologies were scouted and vetted, a structured technology transfer process, and annual “game-changer” projects.

The (B) case describes how the CTO office team members in 2011 again solicited advice from their ecosystem of thought leaders and held workshops to significantly enhance their impact. As a result, they began developing solutions for broader, more fundamental business problems that came to be known as Grand Challenges: extremely difficult business problems whose solutions could potentially create hundreds of millions—or billions—of dollars in business value.

After reading and analyzing the case, students will be able to:

• Understand the management challenges associated with realizing the business value of new technologies

• Explore how innovation management evolves as an innovation team learns from its successes and failures and, more importantly, builds a reputation within and outside the company

• Examine a prototypical “advocate” model of corporate entrepreneurial practice

• Explore a leading example of a successful internal innovation program

Understand the management challenges associated with realizing the business value of new technologies

Explore how innovation management evolves as an innovation team learns from its successes and failures and, more importantly, builds a reputation within and outside the company

Examine a prototypical “advocate” model of corporate entrepreneurial practice

Explore a leading example of a successful internal innovation program

Communication in any organization is a complex phenomenon. Public schools are people‐centered enterprises in which the primary tasks of teaching and learning are accomplished verbally. Within each school, the principal is uniquely positioned to regulate these communications activities. The research reported here sought to examine how five school principals managed communications in their schools. Three major questions guided the research. What are the preferred modes and levels of communications activities utilized by principals? What are the major messages communicated through various modes and at different levels by principals? What do the communications activities of individual principals tell us about how principals interpret their leadership role in school, how they set administrative priorities, and how they put their beliefs and values into practice? The findings indicate that the communications activities of school principals are dominated by dyadic interpersonal contacts. The major purpose of these dyadic interpersonal exchanges were maintenance messages which related to policies, procedures, and regulations for organizing, operating and perpetuating the school. As an adaptation to the nature of a principal's work life, each principal demonstrated a pragmatic preference for accomplishing his/her communications through talk even when written messages or other mechanisms for message delivery would have been more efficient. Finally, the principals believed that the success of their communications activities in school was characterized by openness, honesty, high visibility, and the ability and capacity to listen.