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Boundary layers, which develop during manufacturing and operation, can protect tooth flanks from metal-to-metal contacts. The characteristics of boundary layers and the running behavior of gears are determined by the preconditioning processes (manufacturing and run-in). This paper aims to analyze the influence of the grinding process parameters and the grinding oil on the characteristics of boundary layers.

Sets of test parts and test gear sets with different grinding process variants and different metalworking fluids were manufactured to investigate the mechanisms of action of thermomechanical and chemical surface preconditioning during grinding. The test parts were analyzed with regard to their boundary layer by metallography and chemistry and regarding their running behavior on test rigs lubricated with transmission oil.

In the tests, reproducible differences in gear strength regarding low-cycle fatigue and micropitting were determined for the test parts ground with different thermomechanical energy inputs and with different metalworking fluids. As the test results could not be sufficiently explained on the basis of conventionally tolerated component properties such as roughness, hardness and residual stresses, a model was discussed which combines the mechanisms of action of the formation of the manufacturing-induced boundary layer with the running behavior of the parts.

By combining both measurement and test results, possible correlations between manufacturing and operation are investigated to establish a more sustainable and economical design of gears.

Laser systems are becoming more and more a commodity in many fields of application and this is driving a strong trend towards increasingly efficient production technologies and miniaturized products. A central aspect of laser production is the assembly where the majority of cost is due to manual operations. Resistance soldering of optical components is an upcoming technology for automated assembly, especially for high power laser applications. This technology transfers design and packaging concepts from the electronics industry into photonics. The purpose of this paper is to present recent developments in the field of this soldering technology and to show the first experimental results in combination with robot‐based handling.

Soldering results were examined by resistance measurements, shear testing and optical analysis of the melting zone.

The experiments conducted proved the viability of robot‐based automated resistance soldering of optical components. Analyses of current and voltage profiles gave valuable information for process control possibilities without additional sensors and validated the theoretical considerations of the temperature dependency of material properties. Shear testing underlined the necessity for accurate mechanical contact arrangement and opened fields for further process developments.

Robot‐based resistance soldering of optical components represents a promising joining technology for the automated assembly of laser systems. Existing solutions with mechanical fixtures hamper the miniaturization of optical systems and concurrently increase material and production costs. Manual and semi‐automated gluing of components is an alternative process with significant disadvantages regarding the robustness of the process and the resulting joint connection.

Social movement scholars have increasingly drawn attention to the process of “bridge building” in social movements – that is, the process by which activists attempt to resolve conflicts stemming from different collective identities. However, most scholars assume that social movements primarily attempt to resolve tensions among activists themselves, and thus that bridge building is a means to other ends rather than a primary goal of social movement activism. In this chapter, I challenge these assumptions through a case study of a “bridging organization” known as Bridge Builders, which sought as its primary goal to “bridge the gap between the LGBT and Christian communities” at a Christian university in Nashville, Tennessee. I highlight the mechanisms by which Bridge Builders attempted to facilitate bridge building at the university, and I argue that Bridge Builders succeeded in bridging (a) disparate institutional identities at their university, (b) “structural holes” between LGBT- and religious-identified groups at their university, and (c) oppositional personal identities among organizational members. As I discuss in the conclusion, the case of Bridge Builders has implications for literatures on bridge building in social movements, cultural and biographical consequences of social movements, and social movement strategy.

This chapter argues that the dead are stakeholders and that they should be regarded as such. In making that argument I will be exploring the claims of the philosopher Bob Brecher (2002) that we have real obligations to the dead because they made us what we are, if they were a part of our community. Indeed, Brecher (2002) argues that the dead never ceased ‘to be members of a particular community’ and therefore ‘the dead can be said to have interests’. This chapter explores the validity of their interests as stakeholders. Indeed, I argue that if they are not regarded as stakeholders, corporate management will overlook their interests. Admittedly, corporate managers might seem mindful of their interests. However, if they are not conceived of as stakeholders, such managers will not be primarily concerned with their interests, but with how other stakeholders might perceive those interests. In attempting to satisfy these other stakeholders’ perceptions of those interests, the actual interests of the dead could be overlooked. But that relies on the dead being legitimate stakeholders. To substantiate that status I therefore argue in this chapter that the dead are stakeholders, but also that their status as a stakeholder now that they are dead is dependent on their behaviour when they were alive, given Brecher's (2002) insistence as to them being a part of that community.

In arguing this, I utilize a recent article by Rosenbloom and Althaus (2010). I argue that the interest of the dead they mention in their article would best be served if they are considered as stakeholders. Indeed, that because Rosenbloom and Althaus (2010) do not consider those dead as stakeholders, their interests are never considered. I acknowledge though that being stakeholders relies on them remaining a part of that community (Brecher, 2002), which I argue they were a part of. If they do not remain a part of that community, I cannot argue that they are stakeholders. I therefore consider a historical argument which if accepted would prove that the dead which Rosenbloom and Althaus (2010) consider had not remained a part of that community and therefore cannot be accepted as stakeholders. This chapter rigorously examines the validity of that historical argument as to the behaviour of those dead when they were living, and whether their behaviour negates any claims as to them being stakeholders. This chapter completely refutes any arguments as to these dead being involved in such activities which would have removed them from their community and thus from being stakeholders. It furthermore argues that successfully rebutting such arguments is essential to my argument that the dead I am considering are stakeholders.

This chapter describes why safe spaces are needed in education settings for full inclusion of gendered identities as they intersect with categories such as race/ethnicity, class, sexual orientation, and ability. This discussion briefly addresses varying and intersecting levels and domains of privilege or marginalization such as identity, inter-/intraaction, organization, society, and knowledge, and how safe spaces in education can support learning as it is entwined with gender, gendered biases, and power dynamics and structures.

The purpose of this study is to optimize high-strength gears produced by powder metallurgical process and to provide a material model to predict the tooth root bending fatigue strength. Powder metal (PM) technology offers great opportunities for the reduction of the carbon footprint and improvement of the cost efficiency of gear production. PM gears can achieve flank load-carrying capacities comparable to wrought steel gears if the loaded volume is fully densified. Still, the tooth root strength is of particular importance.

The tooth root stresses can be minimized by optimizing the tooth root geometry. This usually leads to a target conflict, as fully optimized tooth root geometries cannot be manufactured by generating processes such as hobbing, generating-grinding or rolling. To use the increase in tooth root load-carrying capacity of fully optimized root geometry on PM gears, a non-generating method for surface densifying is needed. The shot-peening process is used as an alternative densification process for PM gears. The properties of both shot peened and cold-rolled PM gears are analyzed and compared. To quantify the effect of both manufacturing processes, the tooth root bending fatigue strength will be evaluated and compared to wrought gears.

From the fatigue strength perspective, a material model is developed, which is able to predict local endurable stress amplitudes. The model is gained through regression varying carbon content, density and size effect on bending specimens.

It is transferable to PM gears of the same material using a load transfer coefficient.

Popular accounts of the labor movement suggest that unions have become weak organizations. There are, however, trends that indicate laborʼs political power has not waned in recent years. Using data from multiple sources, the results in this study indicate: (1) despite declines in union density, the percentage of union households has remained steady for two decades; (2) unions continue to produce a strong Democratic vote from its membership, even from its white male members; (3) unions are among the top campaign contributors and spenders in American elections; (4) unions hold significant influence among congressional Democrats and have made gains at the state and local level; and (5) public opinion of labor unions has remained consistently positive for several decades.

After decades of declining strike rates in the industrialized world, recent years have seen a surge of militant walkouts in the global South, political strikes in Europe, and unconventional strikes in nonunion sectors in the United States. This new diversity of strike action calls for a new theoretical framework. In this paper, we review the historical strengths and limits of traditions of strike theory in the United States. Building on the emerging power resources approach, we propose a model based on a multidimensional view of associational power, power resources, and arenas of conflict in the economy, state, and civil society. We demonstrate the utility of our approach via a case analysis of strikes in the “Fight for $15” campaign in the United States.

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 paper aims to present a methodology to help end-users to find appropriate part candidates for the use of the additive manufacturing (AM) technology. These shall be capable of bringing AM into their businesses. The concept furthermore includes approaches for redesigning current available parts and helps to estimate the economic implications of the use of the technology.

The approach starts to discuss general economic aspects for the successful use of AM. While describing the introduction of new technologies into existing businesses, the importance of an appropriate part selection for AM is pointed out. A methodology for a part selection process is presented, and the different criteria are developed. An approach for a redesign of the selected parts, including the gathering of requirements, is given based on different sample parts. A variation of criteria to include measures for product piracy is highlighted.

The methodology has proven applicability in several research and industry projects in aerospace applications. Independent part selections from experts analyzed within a project of the European Space Agency had a 90 per cent overlap with the results. It allows companies with only basic AM knowledge to start a part screening for applicable AM candidates in their own company with a reasonable effort.

The methodology for the redesign process helps to identify the main functions of the products targeted and the relevant environment, so one can benefit from the various advantages that AM has to offer. The selection methodology helps to ask the right questions and to reduce the effort.