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The purpose of this paper is to study the effect of chemical composition on the selective oxidation on the surface of bake hardenable steel, and on the surface of modified bake hardenable steel with titanium addition, annealed at different dew points.

The subject scope of the paper is the selective oxidation. The methodology used is the annealing of steels at different dew points, and the surface characterization by using atomic force microscopy, X‐ray photo electronic spectroscopy, and glow discharge optical emission spectroscopy.

The modified bake hardenable steel showed a higher oxidized area than the bake hardenable steel. The optimum condition for annealing of the bake hardenable steel was at 800°C with −30°C dp and −60°C dp as selective oxidation is less voluminous.

One suggestion for future works is the use of transmission electron microscopy for the evaluation of selective oxidation on the steel surfaces.

One practical implication is the determination of the optimum condition for annealing of the bake hardenable steel in the steel plant, decreasing the selective oxidation and increasing the quality of galvanized steels. Another implication is the discard by the steel industry of the development of the modified bake hardenable steel.

The originality of the present work is to use advanced surface analysis techniques to quantify the selective oxidation on the surface of commercial steels. The selective oxidation on the surface of steels must be minimized in order to increase the wet ability of zinc layer on the steel surface.

This chapter offers insight on how existing paradigms within Black Studies, specifically the ideas of racial capitalism and the Black Radical Tradition, can advance sociological scholarship toward greater understanding of the macro-level factors that shape Black mobilizations. In this chapter, I assess mainstream sociological research on the Civil Rights Movement and theoretical paradigms that emerged from its study, using racial capitalism as a lens to explain dynamics such as the political process of movement emergence, state-sponsored repression, and demobilization. The chapter then focuses on the reparatory justice movement as an example of how racial capitalism perpetuates wide disparities between Black and white people historically and contemporarily, and how reparations activists actively deploy the idea of racial capitalism to address inequities and transform society.

The purpose of this paper is to develop a novel autonomous in‐pipe robot to perform the preventive point reparation for long‐distance offshore oil pipelines.

The autonomous in‐pipe robot performs online ultrasonic inspection for pipe wall thickness, and the original inspection data are stored in large capacity hard disk. Through the offline data analysis by the data analysts and the software tool, the pipeline health status is known. If server defects lie there, the in‐pipe robot is introduced into the pipeline once more to indicate the defect's location to the maintenance ship.

The laboratory tests and the field tests prove the feasibility and validity of the developed autonomous in‐pipe robot. Furthermore, the application of intelligent control techniques ensures the mission completion by the autonomous in‐pipe robot, which worked in the awful pipeline environment.

The developed autonomous in‐pipe robot helps eliminate lost production costs and pipeline downtime caused by leakages and guarantees the safe run of offshore oil pipelines.

For the application of the autonomous in‐pipe robot, there are no special requirements for maintained pipelines themselves, so it is applicable to the point reparation for most long‐distance welded offshore pipelines.

The purpose of this chapter is to examine public apology as a socially acceptable means of institutional communication and the renegotiation of social relations that seeks to redress the power imbalance between the parties to this interaction. After presenting a basic definition of an apology as a communicative act and discussing the social relational implication of the public form of such an act, the paper examines one particular grouping of public apologies – those coming from Canadian Christian church denominations or communities seeking a renewed relationship with Canadian Aboriginal communities. A comparative analysis of the text and context of several of these apology interactions can provide some fascinating hints about the role of public apology in creating a new joint social narrative, affirming common moral norms, clarifying accountability for past relations and empowering the marginalized community through some form of compensation.

The purpose of this study is to show which filler metal is the best for hard facing. Because the quality of the surface layer has a great influence on the working life of parts, the purpose was to extend the working life of parts exposed to intensive wear. The tested hard-faced models were made of low carbon steel to save the expensive base metal and to analyze the possibilities of extending the service life of existing structural parts.

Samples were prepared from plates hard faced with various filler metals. Samples were then subjected to experimental testing – testing of tribological properties and hardness and microstructure. Testing was done in conditions similar to real ones – with a sliding speed of 0.25, 0.5 and 1 m/s and with a load of 50, 75 and 100 N and in most rigorous dry conditions. Research was done by using a combination of experimental and theoretical approaches.

The paper shows the results of the experimental testing of four different filler metals aimed for hard facing of parts exposed to highly intensive wear. Results shown that CrWC 600 alloy is the most favorable filler metal for hard facing of parts such as those of construction mechanization and those subjected to intensive abrasive wear at stone mines.

All obtained results are real and fully applicable, as there is a huge industrial need for these types of technologies. With the application of these technologies, beside money savings, the working life of parts can be significantly extended.

The research presented in this paper was conducted because of the lack of results from this area in Serbia and because of the necessity for application of obtained results in companies for road maintenance and stone excavation in the region of Šumadija, Serbia.

In this article Professor Perry argues that Plessy v. Ferguson and the de jure segregation it heralded has overdetermined the discourse on Jim Crow. She demonstrates through a historical analysis of activist movements, popular literature, and case law that private law, specifically property and contract, were significant aspects of Jim Crow law and culture. The failure to understand the significance of private law has limited the breadth of juridical analyses of how to respond to racial divisions and injustices. Perry therefore contends that a paradigmatic shift is necessary in scholarly analyses of the Jim Crow era, to include private law, and moreover that this shift will enrich our understandings of both historic and current inequalities.

The purpose of this paper is to propose a new way of prototyping surfaces, taking the mathematical background into account, without involving drawing environments.

The authors thicken surfaces from a mathematical point of view to obtain solids. Next they look for an operative procedure to build virtual models and interchange files. The authors build a sample of Enneper thickened surface by fused deposition modelling and verify the prototype by reverse engineering techniques.

The authors provide a formulation able to thicken surfaces in mathematical terms. An operative procedure generates virtual solids and interchange files in the same environment. The approximations necessary for additive fabrication, such as triangulations and mesh geometry, can be chosen at this stage.

The approach is useful at the product/process development stage, in which surfaces are delivered by theoretical analysis. At this stage a prototype can give useful advice permitting functional tests. The limitation is that, when the mathematical formulation is not available, it is difficult to translate a concept without fundamentals of differential geometry.

Approximations of drawing environments typically lead to fault models, not ready for fabrication by additive manufacturing (AM) technologies, needing empiric, not at all obvious and not rapid repair interventions. The authors' approach eliminates this stage, permitting a faster and simple managing of modifications due to functional and technological requirements, that are frequent at concept stage. This leads to a time‐to‐market reduction in the course of product/process development.

This paper extends the capability of a mathematical approach to solve surface prototyping problems. By reducing the required stages, the proposed methodology finds a theoretical and practical shorter route to direct fabrication.

This paper aims to discuss the constitution of the Memorial of Resistance of São Paulo (MRSP) by adopting the ANTi-History approach, thereby providing greater transparency to the socio-political relations of multiple actors involved in the constitution of this place as a site of memory.

By adopting the principles of ANTi-History, the researchers focused on the socio-politics of different human and nonhuman actors to examine how this site of memory was constituted. The researchers sought to turn the process of constituting the MRSP more transparent, putting together one of the possible historical versions of this phenomenon. The data collected included oral and documental sources (interviews, videos, books, newspapers and websites).

The findings support the notion of history as a socially constructed narrative that emerges through associations of heterogeneous actors in a dynamic and continuous process of (re)configuration. Additionally, by exposing the power relations and negotiations manoeuvres used by multiple actors, it allowed the researchers to highlight the complexity of the Memorial’s history as a black box, contextualizing them in a period of intense social upheaval, re-democratization and transitional justice within Brazilian society.

The paper outlines the process of listing the DEOPS/SP building and the social mobilization movements during the 1980s and 1990s in Brazil, illustrating some of the results obtained from a more extensive research project that dealt with the MRSP’s constitution process. It offers an in-depth example of using the ANTi-History approach in Organizational Studies, allowing the researchers to remove the organization’s veil of apparent simplicity and to bring back to life voices and actors that have been erased, disguised and silenced by the dominant version of events.

The purpose of this article is to suggest that Fraby‐Perot optic sensor is a practical measurement gage to monitor the strain of great structures such as railway bridges.

A remote strain monitoring system based on F‐P optic fiber and virtual instrument is designed to monitor the strains of a railway bridge.

The application results show that the Fraby‐Perot optical fiber sensors can accurately measure strain and they are suitable for the long‐term and automatic monitoring. In addition, the system has several advantages over conventional structural instruments including fast response, ability of both static and dynamic monitoring, absolute measurement, immunity to interferences such as lightning strikes, electromagnetic noise and radio frequency, low attenuation of light signals in long fiber optic cables.

Health monitoring of structures is getting more and more recognition all over the world because it can minimize the cost of reparation and maintenance and ensure the safety of structures. A strain monitoring system based on F‐P optic fiber sensor was developed according to the health monitoring requirements of Wuhu Yangtze River Railway Bridge, which is the first cable‐stayed bridge with a maximum span of 312 m carrying both railway and highway traffic in China. It has run stably in the monitoring field more than two years and fulfilled the monitoring requirement very well. Now the system has been transplanted successfully to the Zhengzhou Yellow Railway Bridge for strain monitoring. So the work can be referenced by other similar health monitoring projects.

Long‐term, real‐time monitoring of strain using FP fiber optic sensors in railway bridge is an innovation. A remote strain data acquisition and real‐time processing are another character of the system. The work studied can be referenced by other structures monitoring, such as tunnel, concrete bridges, concrete and earth dams.

HOWEVER good the result, every designer expects, and receives, criticism—mostly adverse. But even the most adverse destructive criticism can be of some value to a designer whose interest is the furtherment and betterment of his work and who does not take criticism as a personal reflection on his ability.