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Narratives about racism and equity in schools have been documented in varying degrees of detail and accuracy in the news media (Farhi, 2012). Thus, race is front and center in the news reports, demonstrating how education policies are detrimental to the Island while also contending that policy drivers of Ley de Reforma Educativa de Puerto Rico (LREPR) are ignoring the racialized consequences of these neoliberal policies.

To examine the implementation of LREPR in education discourse in the media, a content analysis on texts in the Puerto Rican media was conducted. To conduct the analysis, an original dataset of texts from the four major newspapers in Puerto Rico: El Nuevo Dia, El Vocero, Primera Hora and The San Juan Daily Star (n = 119) was created.

The study shows how the collective resistance of Puerto Ricans towards LREPR suggests racialized consequences for this “post”-colonial Island as they engage in dialogues about property rights and dispute policy discourse. Data suggests the alarming effects of neoliberalism as perceived by Puerto Rican citizens, while highlighting shared concerns aligned with elements of critical race theory such as colorblindness and property rights.

This study breaks ground by identifying a new intellectual pursuit of charter schools purchasing land or buildings in marginalized communities. It argues that the news coverage demonstrates how Puerto Rican citizens have illuminated the purchase of land for charter schools, viewing it as an act of colonialism veiled as market competition and economic improvement for the Island. Implications for policy and practice are discussed.

The findings from this research contribute to how critical race theory is used and conceptualized in the educational leadership field. Additionally, the study contributes to the field of research by conducting a content analysis of newspaper articles in Puerto Rico, looking through the CRT lens to illuminate systemic racism that is present in media accounts of education.

This paper aims to investigate the process by which performative technologies (PTs), in this case accreditation work in a business school, take form and how humans engage in making up such practices. It studies how academics come to accept and even identify with the quantitative representations of themselves in a translation process.

The research involved a longitudinal, self-ethnographic case study that followed the accreditation process of one Nordic business school from 2015 to 2021.

The findings show how the PT pushed for different engagements in various phases of the translation process. Early in the translation process, the PT promoted engagement because of self-realization and the ability for academics to proactively influence the prospective competitive milieu. However, as academic qualities became fabricated into numbers, the PT was able to request compliance, but also to induce self-reflection and self-discipline by forcing academics to compare themselves to set qualities and measures.

The paper advances the field by linking five phases of the translation process, problematization, fabrication, materialization, commensuration and stabilization, to a discussion of why academics come to accept and identify with the quantitative representations of themselves. The results highlight that the materialization phase appears to be the critical point at which calculative practices become persuasive and start influencing academics’ thoughts and actions.

Component positioning is an important part of aircraft assembly, aiming at the problem that it is difficult to accurately fall into the corresponding ball socket for the ball head connected with aircraft component. This study aims to propose a ball head adaptive positioning method based on impedance control.

First, a target impedance model for ball head positioning is constructed, and a reference positioning trajectory is generated online based on the contact force between the ball head and the ball socket. Second, the target impedance parameters were optimized based on the artificial fish swarm algorithm. Third, to improve the robustness of the impedance controller in unknown environments, a controller is designed based on model reference adaptive control (MRAC) theory and an adaptive impedance control model is built in the Simulink environment. Finally, a series of ball head positioning experiments are carried out.

During the positioning of the ball head, the contact force between the ball head and the ball socket is maintained at a low level. After the positioning, the horizontal contact force between the ball head and the socket is less than 2 N. When the position of the contact environment has the same change during ball head positioning, the contact force between the ball head and the ball socket under standard impedance control will increase to 44 N, while the contact force of the ball head and the ball socket under adaptive impedance control will only increase to 19 N.

In this paper, impedance control is used to decouple the force-position relationship of the ball head during positioning, which makes the entire process of ball head positioning complete under low stress conditions. At the same time, by constructing an adaptive impedance controller based on MRAC, the robustness of the positioning system under changes in the contact environment position is greatly improved.

This study aims to investigate the reliability issues of microvoid cracks in solder joint packages exposed to thermal cycling fatigue.

The specimens are subjected to JEDEC preconditioning level 1 (85 °C/85%RH/168 h) with five times reflow at 270°C. This is followed by thermal cycling from 0°C to 100°C, per IPC-7351B standards. The specimens' cross-sections are inspected for crack growth and propagation under backscattered scanning electronic microscopy. The decoupled thermomechanical simulation technique is applied to investigate the thermal fatigue behavior. The impacts of crack length on the stress and fatigue behavior of the package are investigated.

Cracks are initiated from the ball grid array corner of the solder joint, propagating through the transverse section of the solder ball. The crack growth increases continuously up to 0.25-mm crack length, then slows down afterward. The J-integral and stress intensity factor (SIF) values at the crack tip decrease with increased crack length. Before 0.15-mm crack length, J-integral and SIF reduce slightly with crack length and are comparatively higher, resulting in a rapid increase in crack mouth opening displacement (CMOD). Beyond 0.25-mm crack length, the values significantly decline, that there is not much possibility of crack growth, resulting in a negligible change in CMOD value. This explains the crack growth arrest obtained after 0.25-mm crack length.

This work's contribution is expected to reduce the additional manufacturing cost and lead time incurred in investigating reliability issues in solder joints.

The work investigates crack propagation mechanisms of microvoid cracks in solder joints exposed to moisture and thermal fatigue, which is still limited in the literature. The parametric variation of the crack length on stress and fatigue characteristics of solder joints, which has never been conducted, is also studied.

This study aims to focus on the surface mount technology (SMT) mass production process of Sn-9Zn-2.5Bi-1.5In solder. It explores it with some components that will provide theoretical support for the industrial SMT application of Sn-Zn solder.

This study evaluates the properties of solder pastes and selects a more appropriate reflow parameter by comparing the microstructure of solder joints with different reflow soldering profile parameters. The aim is to provide an economical and reliable process for SMT production in the industry.

Solder paste wettability and solder ball testing in a nitrogen environment with an oxygen content of 3,000 ppm meet the requirements of industrial production. The printing performance of the solder paste is good and can achieve a printing rate of 100–160 mm/s. When soldering with a traditional stepped reflow soldering profile, air bubbles are generated on the surface of the solder joint, and there are many voids and defects in the solder joint. A linear reflow soldering profile reduces the residence time below the melting point of the solder paste (approximately 110 s). This reduces the time the zinc is oxidized, reducing solder joint defects. The joint strength of tin-zinc joints soldered with the optimized reflow parameters is close to that of Sn-58Bi and SAC305, with high joint strength.

This study attempts to industrialize the application of Sn-Zn solder and solves the problem that Sn-Zn solder paste is prone to be oxidized in the application and obtains the SMT process parameters suitable for Sn-9Zn-2.5Bi-1.5In solder.

This paper aims to illustrate, by means of a content analysis of 278 weekly School Meeting minutes, the ways in which student voice is actualized in one democratic free school in Germany.

This paper uses a qualitative content analysis methodology of 278 weekly School Meetings minutes.

This paper uses Fielding’s (2012) patterns of partnership typology to illustrate what counts as student voice and participation in a democratic free school.

Limitations included being reliant on translations of German texts, some missing minutes from the entire set, the lack of a single author for the minutes (and thus degree of detail differs) and the fact that the School Meeting minutes make reference to other meetings for various sub-committees for which no minutes exist, and thus, findings on the degree of student voice may be limited. And because this is a study of one school, generalizability may be difficult. Future research into these sub-committee meetings would prove helpful as well as content analyses of other democratic free schools’ meeting minutes.

This study can help people more deeply understand what goes on in democratic free schools and what student voice and participation can mean within this context.

This study aims to investigate the thermal fracture mechanism of moisture-preconditioned SAC305 ball grid array (BGA) solder joints subjected to multiple reflow and thermal cycling.

The BGA package samples are subjected to JEDEC Level 1 accelerated moisture treatment (85 °C/85%RH/168 h) with five times reflow at 270 °C. This is followed by multiple thermal cycling from 0 °C to 100 °C for 40 min per cycle, per IPC-7351B standards. For fracture investigation, the cross-sections of the samples are examined and analysed using the dye-and-pry technique and backscattered scanning electron microscopy. The packages' microstructures are characterized using an energy-dispersive X-ray spectroscopy approach. Also, the package assembly is investigated using the Darveaux numerical simulation method.

The study found that critical strain density is exhibited at the component pad/solder interface of the solder joint located at the most distant point from the axes of symmetry of the package assembly. The fracture mechanism is a crack fracture formed at the solder's exterior edges and grows across the joint's transverse section. It was established that Au content in the formed intermetallic compound greatly impacts fracture growth in the solder joint interface, with a composition above 5 Wt.% Au regarded as an unsafe level for reliability. The elongation of the crack is aided by the brittle nature of the Au-Sn interface through which the crack propagates. It is inferred that refining the solder matrix elemental compound can strengthen and improve the reliability of solder joints.

Inspection lead time and additional manufacturing expenses spent on investigating reliability issues in BGA solder joints can be reduced using the study's findings on understanding the solder joint fracture mechanism.

Limited studies exist on the thermal fracture mechanism of moisture-preconditioned BGA solder joints exposed to both multiple reflow and thermal cycling. This study applied both numerical and experimental techniques to examine the reliability issue.

Purpose: The research determines how the COVID-19 pandemic affected India’s burgeoning education technology sector and how the new normal responded to this advancement worldwide.

Need for Study: India’s education sector saw a boom in Ed-Tech funding during the pandemic. The Indian Education industry adopted technology as a partner and succeeded in being called as the Ed-Tech capital of the world. The country has a strategic edge in online education that, if explored and researched upon, can be deployed for market growth at a global level.

Research Methodology: The researcher prioritised rigorous original quantitative and qualitative methods of investigation on technology applications in educational contexts during COVID-19 pandemic and drew its conclusions after conducting a comprehensive literature review and collecting and analysing the data from numerous journals and published expert articles on the sector.

Findings: The study found that despite the global pandemic, the Ed-Tech industry was an expanding marketplace for start-ups in India. After the pandemic, the market expanded rapidly, and by 2025, it is expected to have quadrupled in size, expenditure, and investment. It is expected that the global e-learning business, which the outbreak of the COVID-19 pandemic has bolstered, will grow to over 400 billion US dollars by 2026.

Practical Implications: The study sets forth the various Ed-Tech categories, outlining their user bases, growth projections, and the innovative technologies employed in developing these products. The research’s long-term investment projections are envisioned to aid consultants in positioning themselves for profitable operations in the era of digital Ed-Tech disruption worldwide.

This paper aims to study the synergistic lubrication effects of Sn–Ag–Cu and MXene–Ti₃C₂ to improve the tribological properties of M50 bearing steel with microporous channels.

M50 matrix self-lubricating composites (MMSC) were designed and prepared by filling Sn–Ag–Cu and MXene–Ti₃C₂ in the microporous channels of M50 bearing steel. The tribology performance testing of as-prepared samples was executed with a multifunction tribometer. The optimum hole size and lubricant content, as well as self-lubricating mechanism of MMSC, were studied.

The tribological properties of MMSC are strongly dependent on the synergistic lubrication effect of MXene–Ti₃C₂ and Sn–Ag–Cu. When the hole size of microchannel is 1 mm and the content of MXene–Ti₃C₂ in mixed lubricant is 4 wt.%, MMSC shows the lowest friction coefficient and wear rate. The Sn–Ag–Cu and MXene–Ti₃C₂ are extruded from the microporous channels and spread to the friction interface, and a relatively complete lubricating film is formed at the friction interface. Meanwhile, the synergistic lubrication of Sn–Ag–Cu and MXene–Ti₃C₂ can improve the stability of the lubricating film, thus the excellent tribological property of MMSC is obtained.

The results help in deep understanding of the synergistic lubrication effects of Sn–Ag–Cu and MXene–Ti₃C₂ on the tribological properties of M50 bearing steel. This work also provides a useful reference for the tribological design of mechanical components by combining surface texture with solid lubrication.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2023-0381/

In Denmark, there has been, over decades, an intensified political focus on how humanities research and doctoral education contribute to society. In this vein, the notion of impact has become a central part of the academic language, often associated with terms like use, effects and outputs, stemming from neoliberal ideologies. The purpose of this paper is to explore how humanities academics are living with the impact agenda, as both experienced researchers and as doctoral supervisors educating the next generation of researchers in this post-pandemic era. Specifically, the authors are interested in the supervisor-researcher relationship, that is, the relationship between how the supervisors navigate the impact agenda as researchers and then the way they tell their doctoral students to do likewise.

The authors have studied how the impact agenda is accommodated by humanities academics through a series of qualitative interviews with humanities researchers and humanities PhD supervisors, encompassing questions of how they are living with the expectation of impact and how it is embedded in their university and departmental context.

The study shows that there is no link between how the supervisors navigate the impact agenda in relation to their own research work and then the way they tell their doctoral students to approach it. Within the space of their own research, the supervisors engage in resistance practices towards the impact agenda in terms of minimal compliance, rejection or resignation, whereas in the space of supervision, the impact agenda is re-inscribed to embody other understandings. The supervisors want to protect their students from this agenda, especially in the knowledge that many of them are not going to stay in academia due to limited researcher career possibilities. Furthermore, the paper reveals a new understanding of the impact agenda as having a relational quality, and in two ways. One is through a positional struggle, the reshaping of power relations, between universities (or academics) and society (or the state and the market); the other is as a phenomenon very much lived among academics themselves, including between supervisors and their doctoral students within the institutional context.

This study opens up the impact agenda, showing what it means to be a humanities academic living with the effects of the impact agenda and trying to navigate this. The study is mapping and tracking out the many different meanings and variations of impact in all its volatility for academics concerned about it. In current, post-pandemic times, when manifold expectations are directed towards research and doctoral education, it is important to know more about how these expectations affect and are dealt with by those who are expected to commit to them.