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This paper investigates wetting and infiltration of zirconium diboride by copper and copper/boron alloys in order to more effectively create electrodes for electrical discharge machining.

A high temperature furnace outfitted with a video recording system was utilized to observe wetting angles between molten copper alloys and zirconium diboride at various temperatures. A parallel, investigation of the thermodynamics involved with oxidation in the system was also undertaken.

This study showed that zirconium diboride can be wet by pure copper under carefully controlled conditions where oxygen contamination is minimized, and that the wetting angle increases with increasing temperature. Thermodynamic calculations reinforce the contention that oxygen contamination is the key barrier to wetting and infiltration. The addition of boron to copper significantly improves the wetting characteristics, and enables wetting and infiltration under higher oxygen contamination conditions.

This study illustrated that boron must be added to copper to achieve infiltration when surface oxides are present.

Infiltration of porous 3D green shapes of ceramics and metals is a common method for producing metal and ceramic components using rapid prototyping. Good wetting of the porous material by the infiltrant material is necessary for successful infiltration using capillary forces. This paper illustrates the alloys and conditions under which it is possible to produce electrodes of zirconium diboride/copper using rapid prototyping.

This paper presents a new 3D offset method for modifying CAD model data in the STL format. In this method, vertices, instead of facets, are offset. The magnitude and direction of each vertex offset is calculated using the weighted sum of the normals of the facets that are connected to each vertex. To facilitate the vertex offset calculation, topological information is generated from the collection of unordered triangular facets making up the STL file. A straightforward algorithm is used to calculate the vertex offset using the adjoining facet normals, as identified from the topological information. This newly developed technique can successfully generate inward or outward offsets for STL models. As with any offset methodology, this technique has benefits and drawbacks, which will be discussed in this paper. Finally, conclusions will be made regarding the applicability of the developed methodology.

This paper presents an offset‐based tool path generation method for STL format three‐dimensional (3D) models. The created tool‐paths can be effectively used to near‐net‐shaped parts, in particular those created using rapid prototyping.

The STL model is first offset by the distance of the selected cutter radius using a unique 3D offset method. The intersections between the top facing triangles of the offset model and tool‐path drive planes are calculated. The intersection line segments are sorted, trimmed and linked to generate continuous top envelope curves, which represent interference‐free tool paths.

The developed offset‐based algorithm can rapidly and successfully generate interference‐free tool paths as continuous lines, instead of a collection of discrete tool location points. The strategy of using adaptive step‐over distances based on local geometrical information can significantly increase machining efficiency.

The current tool path generation method only works for ball‐end mills. The entire surface of the STL model is treated as a single composite surface to be machined using raster milling. To improve machining efficiency, an automatic surface splitting algorithm could be developed to divide the model into several regions based on the characteristics of a group of triangular facets, and then machine these identified regions using different strategies and cutters.

The offset‐based tool‐path generation algorithm from STL models is a unique and novel development, which is useful in the rapid prototyping and computer‐aided machining areas.

This paper presents a unique method to recognize circular holes from 3D models in the STL format. The topological information generated by this method enables identification of holes and tool path generation for holes which should be drilled rather than milled.

A method based on a set of developed algorithms is used to identify closed loops from a STL model, identify which closed loops correspond to cylindrical holes, find hole orientations, locations and diameters, and calculate the depth for the recognized holes. The developed procedure and algorithms have been implemented in Visual C++ to illustrate the efficacy of the method.

The implementation results showed that the developed algorithms can successfully recognize circular holes of differing sizes on both simple and complex surfaces, and in any orientation. Tool paths can thus be generated from STL models to more efficiently and accurately machine circular holes.

The developed method requires that at least one simple closed loop exist for each potential hole.

A new and unique hole recognition method for use with STL models was developed. This method is useful for accurately and efficiently machining parts with circular holes from STL models as well as finish machining near‐net shape parts with circular holes created using rapid prototyping.

Existing algorithms for predicting suicide risk rely solely on data from electronic health records, but such models could be improved through the incorporation of publicly available socioeconomic data – such as financial, legal, life event and sociodemographic data. The purpose of this study is to understand the complex ethical and privacy implications of incorporating sociodemographic data within the health context. This paper presents results from a survey exploring what the general public’s knowledge and concerns are about such publicly available data and the appropriateness of using it in suicide risk prediction algorithms.

A survey was developed to measure public opinion about privacy concerns with using socioeconomic data across different contexts. This paper presented respondents with multiple vignettes that described scenarios situated in medical, private business and social media contexts, and asked participants to rate their level of concern over the context and what factor contributed most to their level of concern. Specific to suicide prediction, this paper presented respondents with various data attributes that could potentially be used in the context of a suicide risk algorithm and asked participants to rate how concerned they would be if each attribute was used for this purpose.

The authors found considerable concern across the various contexts represented in their vignettes, with greatest concern in vignettes that focused on the use of personal information within the medical context. Specific to the question of incorporating socioeconomic data within suicide risk prediction models, the results of this study show a clear concern from all participants in data attributes related to income, crime and court records, and assets. Data about one’s household were also particularly concerns for the respondents, suggesting that even if one might be comfortable with their own being used for risk modeling, data about other household members is more problematic.

Previous studies on the privacy concerns that arise when integrating data pertaining to various contexts of people’s lives into algorithmic and related computational models have approached these questions from individual contexts. This study differs in that it captured the variation in privacy concerns across multiple contexts. Also, this study specifically assessed the ethical concerns related to a suicide prediction model and determining people’s awareness of the publicness of select data attributes, as well as which of these data attributes generated the most concern in such a context. To the best of the authors’ knowledge, this is the first study to pursue this question.

Past research on the immigrant health paradox suggests that children with immigrant parents may have a health advantage over those with US-born parents, especially if the parent is a recent immigrant. Other research emphasizes the social and economic challenges children with immigrant parents face, in part due to disadvantaged social class and racial/ethnic positions. Underlying physiological changes due to chronic stress exposures among children in immigrant families is one potential health disadvantage that may not yet be apparent in traditional health measures. To explore these biological disparities during childhood, I use national biomarker and survey data from the National Health and Nutrition Survey (NHANES) (N = 11,866) to evaluate parent nativity and educational status associations with low-grade inflammation, indicated by C-reactive protein (CRP), in children ages 2–15 years. I find that children with an immigrant parent, and particularly a low-educated immigrant parent, have higher CRP, net of birth, body mass index (BMI) and other factors, than children with a US-born parent with either a low or higher education. Comparing children with low-educated parents, those with a foreign-born parent have higher predicted CRP. The findings from this study provide new evidence that children living in immigrant families in the US may be facing higher levels of chronic stress exposure, as indicated by the increased risk of low-grade inflammation, than those with US-born parents. The physiological changes related to increased risk of inflammation, could set children in immigrant families on pathways toward mental and physical health problems later in the life course.

The children returned and Ms. Lee had them go to their desks. There was so much excitement in the air … . Ms. Lee has rearranged the desks again and I like how there are such frequent shifts in seating. Ms. Lee spoke of their photographs and their collages. She then said I would give the guiding question for their work on the citizenship education project today in their small sustained response groups. I fumbled badly and said something about who they are and how they belong. Ms. Lee wrote it on the board. As Ms. Lee continued to speak, I went and changed the words to “Who I am and how I belong.” Ms. Lee spoke to the children of how they were going to start putting their photos on their poster boards and to think about how their photographs were representations of who they were and where they belonged. No glue or scissors at this point. She also showed them the paper where she wanted them to write about their photographs.The children got their individual pieces of bristol board for their collages and Ms. Lee said they might want to choose a spot on the floor as they did this work. They were intent and focused on their own photographs but were also sharing with their neighbours. At one point, I commented to Ms. Lee, Simmee, and Jennifer about how impressed I was with their intentness. I spent some time with Logan who had some magnificent photographs … he has an eye for the aesthetic. I pointed out to him how much I liked the photographs. I also spent some time with Taylor who had three photographs of clothes: one Chinese outfit, one Korean outfit, and a long white dress that she said she did not know what it was. I asked if it was a christening dress and she said she thought so, that her mom had taken the photograph. She also had a close up of a Canadian flag. I spent some time with Sophie who had rejected some of her photographs as not interesting. When I pointed out what I saw as interesting things in her photographs, she started to see them more positively. I asked a few children what they planned to put in the centre of their collages. I realized, even as I asked that question, that I was privileging the centre photograph. Liam had his dad's photo clearly in the centre. He was busily writing words. He said he wasn't sure what to write about his dad but then wrote something about family being important. (Field notes, April 2, 2007)

Modern slavery is a problem that international business (IB) research can no longer ignore. Multinational enterprises (MNEs) are often contributors to the persistence of modern slavery, by virtue of the regulatory challenge they pose to states and their insufficient oversight of supply chains. The purpose of this paper is to show that governance inadequacies with respect to modern slavery will be lessened if IB scholars give more attention to MNEs’ governing role within and beyond global value chains.

A set of arguments is presented in support of intensified effort in IB research with respect to studying the role of MNEs in transnational labour governance. The paper draws inspiration from IB theory and the conceptualisation of the MNE in neighbouring disciplines that regard it as a bearer of duties toward labour, consistent with its role in multilevel governance. Insights from the literature on global and multi-level governance are utilised.

The paper construes modern slavery as a multi-level governance challenge and argues that MNE capabilities and responsibilities with respect to labour governance and the deterrence of slavery exceed those identified on the margins of IB literature. MNEs are underappreciated as governors within the multilevel transnational labour governance system. The IB discipline is in a strong position to develop our understanding of the MNE’s different roles in governance and thereby contribute to the reduced incidence of modern slavery.

This paper represents an attempt to mobilise the IB academy to help eliminate slavery from workplaces that rely on MNE patronage or where labour rights abuses are made possible by MNE diversion of governance resources. It places particular emphasis on the use and abuse of MNEs’ governance capabilities in the sphere of international relations and calls attention to over-simplification of the MNE, IB’s primary unit of analysis.

The purpose is to assess the impact of online platforms on the sex industry, focusing specifically on direct sex work, and evaluate what approaches to platform regulation is likely to align with the interests of sex workers.

The paper presents a review of interdisciplinary conceptual and empirical literature on sex work combined with analysis of key issues using a transaction cost framework.

Online platforms generally make sex work safer. Regulation aimed at preventing platforms from serving sex workers is likely to harm their welfare.

Regulation of online platforms should take great care to differentiate coercive sex from consensual sex work, and allow sex workers to experiment with governance mechanisms provided by entrepreneurs.

The paper demonstrates how a transactions costs approach to market behaviour as applied to personal services like ridesharing can also shed light on the challenges that sex workers face, partly as a result of criminalisation, and the dangers of over-regulation.

Victim narratives consistent with anti-trafficking and anti-prostitution rhetoric leave little room for understanding agential labor in the sex industry, which profoundly impacts sex workers’ experiences in other domains. One such domain – academia – is often understood as antithetical to the “body work” of sex work. It is, after all, the domain of the mind. Drawing from my experiences as an undergraduate and graduate student as well as from my work as a sex worker, I use auto-ethnography to demonstrate the lasting impact of (1) mind/body dualisms, (2) the virgin/whore dichotomy, and (3) narratives of sexual danger on perceptions of legitimation and status for sex workers in academia. I also discuss implications for broader social concerns like legal policy.