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Ultrasonic additive manufacturing (UAM) is a rapid prototyping process through which multiple thin layers of material are sequentially ultrasonically welded together to…
Ultrasonic additive manufacturing (UAM) is a rapid prototyping process through which multiple thin layers of material are sequentially ultrasonically welded together to form a finished part. While previous research into the peak temperatures experienced during UAM have been documented, a thorough examination of the heating and cooling curves has not been conducted to date.
For this study, UAM weldments made from aluminum 3003‐H18 tapes with embedded Type‐K thermocouples were examined. Finite element modeling was used to compare the theoretical thermal diffusion rates during heating to the observed heating patterns. A model was used to calculate the effective thermal diffusivity of the UAM build on cooling based on the observed cooling curves and curve fitting analysis.
Embedded thermocouple data revealed simultaneous temperature increases throughout all interfaces of the UAM build directly beneath the sonotrode. Modeling of the heating curves revealed a delay of at least 0.5 seconds should have existed if heating of lower interfaces was a result of thermal diffusion alone. As this is not the case, it was concluded that ultrasonic energy is absorbed and converted to heat at every interface beneath the sonotrode. The calculated thermal diffusivity of the build on cooling was less than 1 percent of the reported values of bulk aluminum, suggesting that voids and oxides along interfaces throughout the build may be inhibiting thermal diffusion through thermal contact resistance across the interface.
This work systematically analyzed the thermal profiles that develop during the UAM process. The simultaneous heating phenomenon presented here has not been documented by other research programs. The findings presented here will enable future researchers to develop more accurate models of the UAM process, potentially leading to improved UAM bond quality.
Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination…
Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.
This chapter presents empirical evidence on the effects of attributional retraining (AR), a motivation-enhancing treatment that can offset maladaptive explanatory…
This chapter presents empirical evidence on the effects of attributional retraining (AR), a motivation-enhancing treatment that can offset maladaptive explanatory mind-sets arising from adverse learning experiences. The evidence shows that AR is effective for assisting college students to adapt to competitive and challenging achievement settings.
This chapter describes the characteristics of AR protocols and details three primary advances in studying AR efficacy in terms of achievement performance, psychosocial outcomes, and processes that mediate AR-performance linkages. The psychological mechanisms that underpin AR effects on motivation and performance are outlined from the perspective of Weiner’s (1974, 1986, 2012) attribution theory.
Laboratory and field studies show that AR treatments are potent interventions that have short-term and long-lasting psychosocial, motivation, and performance benefits in achievement settings. Students who participate in AR programs are better off than their no-AR counterparts not just in their cognitive and affective prospects, but they also outperform their no-AR peers in class tests, course grades, and grade-point-averages, and are more persistent in terms of course credits and graduation rates.
This paper contributes to the emerging literature on treatment interventions in achievement settings by documenting key advances in the development of AR protocols and by identifying the next steps critical to moving the literature forward. Further progress in understanding AR efficacy will rest on examining the analysis of complex attributional thinking, the mediation of AR treatment effects, and the boundary conditions that moderate AR treatment efficacy.
Develops an original 12‐step management of technology protocol and applies it to 51 applications which range from Du Pont’s failure in Nylon to the Single Online Trade…
Develops an original 12‐step management of technology protocol and applies it to 51 applications which range from Du Pont’s failure in Nylon to the Single Online Trade Exchange for Auto Parts procurement by GM, Ford, Daimler‐Chrysler and Renault‐Nissan. Provides many case studies with regards to the adoption of technology and describes seven chief technology officer characteristics. Discusses common errors when companies invest in technology and considers the probabilities of success. Provides 175 questions and answers to reinforce the concepts introduced. States that this substantial journal is aimed primarily at the present and potential chief technology officer to assist their survival and success in national and international markets.
The Bureau of Economics in the Federal Trade Commission has a three-part role in the Agency and the strength of its functions changed over time depending on the preferences and ideology of the FTC’s leaders, developments in the field of economics, and the tenor of the times. The over-riding current role is to provide well considered, unbiased economic advice regarding antitrust and consumer protection law enforcement cases to the legal staff and the Commission. The second role, which long ago was primary, is to provide reports on investigations of various industries to the public and public officials. This role was more recently called research or “policy R&D”. A third role is to advocate for competition and markets both domestically and internationally. As a practical matter, the provision of economic advice to the FTC and to the legal staff has required that the economists wear “two hats,” helping the legal staff investigate cases and provide evidence to support law enforcement cases while also providing advice to the legal bureaus and to the Commission on which cases to pursue (thus providing “a second set of eyes” to evaluate cases). There is sometimes a tension in those functions because building a case is not the same as evaluating a case. Economists and the Bureau of Economics have provided such services to the FTC for over 100 years proving that a sub-organization can survive while playing roles that sometimes conflict. Such a life is not, however, always easy or fun.
Recent literature has highlighted the importance of human resource management, knowledge management, and technical innovation as key elements for achieving competitive…
Recent literature has highlighted the importance of human resource management, knowledge management, and technical innovation as key elements for achieving competitive advantage. Furthermore, research has shown a positive relationship between these three variables. However, empirical research on this issue is still scarce. This paper analyzes those linkages using structural equation modeling with data collected from 373 Spanish firms. The findings show that there is a relationship among the variables, although it is more complex than described in previous studies.
Academic and practitioner attention to the constructs of authentic leadership and work engagement and their implications for organizations has grown dramatically over the…
Academic and practitioner attention to the constructs of authentic leadership and work engagement and their implications for organizations has grown dramatically over the past decade. Consideration of the implications of these constructs for high-performance human resource practices (HPHRP) is limited, however. In this monograph, we present a conceptual model that integrates authentic leadership/followership theory with theory and research on HPHRP. Then, we apply this model to systematically consider the implications of skill-enhancing, motivation-enhancing, and opportunity-enhancing HR practices in combination with authentic leadership for authentic followership, follower work engagement, and follower performance. We contend that authentic leadership, through various influences processes, promotes HPHRP, and vice versa, to help foster enhanced work engagement. By cultivating greater work engagement, individuals are motivated to bring their best, most authentic selves to the workplace and are more likely to achieve higher levels of both well-being and performance.
Contemporary literature reveals that, to date, the poultry livestock sector has not received sufficient research attention. This particular industry suffers from…
Contemporary literature reveals that, to date, the poultry livestock sector has not received sufficient research attention. This particular industry suffers from unstructured supply chain practices, lack of awareness of the implications of the sustainability concept and failure to recycle poultry wastes. The current research thus attempts to develop an integrated supply chain model in the context of poultry industry in Bangladesh. The study considers both sustainability and supply chain issues in order to incorporate them in the poultry supply chain. By placing the forward and reverse supply chains in a single framework, existing problems can be resolved to gain economic, social and environmental benefits, which will be more sustainable than the present practices.
The theoretical underpinning of this research is ‘sustainability’ and the ‘supply chain processes’ in order to examine possible improvements in the poultry production process along with waste management. The research adopts the positivist paradigm and ‘design science’ methods with the support of system dynamics (SD) and the case study methods. Initially, a mental model is developed followed by the causal loop diagram based on in-depth interviews, focus group discussions and observation techniques. The causal model helps to understand the linkages between the associated variables for each issue. Finally, the causal loop diagram is transformed into a stock and flow (quantitative) model, which is a prerequisite for SD-based simulation modelling. A decision support system (DSS) is then developed to analyse the complex decision-making process along the supply chains.
The findings reveal that integration of the supply chain can bring economic, social and environmental sustainability along with a structured production process. It is also observed that the poultry industry can apply the model outcomes in the real-life practices with minor adjustments. This present research has both theoretical and practical implications. The proposed model’s unique characteristics in mitigating the existing problems are supported by the sustainability and supply chain theories. As for practical implications, the poultry industry in Bangladesh can follow the proposed supply chain structure (as par the research model) and test various policies via simulation prior to its application. Positive outcomes of the simulation study may provide enough confidence to implement the desired changes within the industry and their supply chain networks.
A distinction must be drawn between a dismissal on the one hand, and on the other a repudiation of a contract of employment as a result of a breach of a fundamental term of that contract. When such a repudiation has been accepted by the innocent party then a termination of employment takes place. Such termination does not constitute dismissal (see London v. James Laidlaw & Sons Ltd (1974) IRLR 136 and Gannon v. J. C. Firth (1976) IRLR 415 EAT).