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High density packaging mounted VLSI demand highly dense and highly accurate multilayer printed wiring boards. The authors have studied Ultra Thin Copper (UTC) technology of printed wiring boards for application to the packages of high speed and high performance computers for more than 10 years. This paper describes the requirement for fine line and highly dense multilayer printed wiring boards and the study of the development of a suitable process using the UTC. The discussions include the behaviour of pattern etching and effects of plating thickness, the improvement of plating thickness uniformity, the selection of carrier types, the measurement of peel strength between copper foil and substrate, and so on. The UTC application reduces the defects caused by surface contamination of epoxy resin. Degradation of surface resistance is also discussed, which may be caused by surface creeping of alkaline ions arising from residues of plating solution within the plated‐through hole wall. These investigations could establish UTC technology for fine line printed wiring boards.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

Job Corps is the United State’s largest and most comprehensive training program for disadvantaged youth aged 16–24 years old. A randomized social experiment concluded that, on average, individuals benefited from the program in the form of higher weekly earnings and employment prospects. At the same time, “young adults” (ages 20–24) realized much higher impacts relative to “adolescents” (ages 16–19). Employing recent nonparametric bounds for causal mediation, we investigate whether these two groups’ disparate effects correspond to them benefiting differentially from distinct aspects of Job Corps, with a particular focus on the attainment of a degree (GED, high school, or vocational). We find that, for young adults, the part of the total effect of Job Corps on earnings (employment) that is due to attaining a degree within the program is at most 41% (32%) of the total effect, whereas for adolescents that part can account for up to 87% (100%) of the total effect. We also find evidence that the magnitude of the part of the effect of Job Corps on the outcomes that works through components of Job Corps other than degree attainment (e.g., social skills, job placement, residential services) is likely higher for young adults than for adolescents. That those other components likely play a more important role for young adults has policy implications for more effectively servicing participants. More generally, our results illustrate how researchers can learn about particular mechanisms of an intervention.

This chapter examines underrepresentation among African American and Hispanic students in gifted education using the perfect storm analogy, arguing that social inequality, elitism, and colorblindness are three forces that contribute to the poor presence of these groups in gifted education. Underrepresentation trends are presented, along with methods for calculating underrepresentation and inequity. Underrepresentation is placed under the larger issues of achievement gaps, and inequitable school practices, specifically de jure segregation. Models and discussions of social inequality, elitism, and colorblindness are presented to explain that the magnitude of underrepresentation is beyond statistical chance and a function of decision makers’ attitudes and beliefs grounded in deficit paradigms. The primary theses and admonitions are that gifted education underrepresentation is counterproductive in such a culturally different nation, and that desegregating gifted education is nonnegotiable. Suggestions for desegregating gifted education and eliminating inequities are provided.

The purpose of this paper is to propose a novel wireless sensor node (SN), with impact resistant capability, for launch deployment into closed areas. In disaster areas, gathering disaster area information is crucially important to prevent secondary disasters. However, gathering information is usually associated with the risk of death and/or accident for rescue workers in closed areas. The authors propose the SN for gathering information in dangerous places, inaccessible to rescue workers and robots, by utilizing launch deployment.

Buffer material is essential when designing an impact‐resistant structure. The authors adopted the air cushion as general buffer material when considering the directional characteristics of sensor mounting and wireless communication quality and developed the expression for determining the thickness of the air cushion using the parameters of SN size, mass, air pressure and acceleration. The authors developed a sensor node with impact resistant structure by utilizing the proposed determination method of air cushion thickness.

In the evaluation of impact resistant structure in free fall, launch deployment, the authors verified that the impact resistant structure protected the SN, and the performance of configured devices on the SN. Then, the authors examined the effect of the impact‐resistant structure on wireless communication between SNs. The structure had no effect on electric field intensity, throughput, or packet jitter, which confirmed that the wireless communication capacity was unaffected by the structure.

In this paper, a new design method is stated for a sensor node with an impact‐resistant structure by utilizing an air cushion as a general buffer material.

The brake pipe system was an essential braking component of the railway freight trains, but the existing E-type sealing rings had problems such as insufficient low-temperature resistance, poor heat stability and short service life. To address these issues, low-phenyl silicone rubber was prepared and tested, and the finite element analysis and experimental studies on the sealing performance of its sealing rings were carried out.

The low-temperature resistance and thermal stability of the prepared low-phenyl silicone rubber were studied using low-temperature tensile testing, differential scanning calorimetry, dynamic thermomechanical analysis and thermogravimetric analysis. The sealing performance of the low-phenyl silicone rubber sealing ring was studied by using finite element analysis software abaqus and experiments.

The prepared low-phenyl silicone rubber sealing ring possessed excellent low-temperature resistance and thermal stability. According to the finite element analysis results, the finish of the flange sealing surface and groove outer edge should be ensured, and extrusion damage should be avoided. The sealing rings were more susceptible to damage in high compression ratio and/or low-temperature environments. When the sealing effect was ensured, a small compression ratio should be selected, and rubbers with hardness and elasticity less affected by temperature should be selected. The prepared low-phenyl silicone rubber sealing ring had zero leakage at both room temperature (RT) and −50 °C.

The innovation of this study is that it provides valuable data and experience for the future development of the sealing rings used in the brake pipe flange joints of the railway freight cars in China.

In this chapter, we discuss the merits and challenges of organic communication within an inclusive, iterative research design through our research project ‘Improving the quality of life of families with parents with intellectual disabilities (IDs) and their children (<12 years) by means of assistive robotics’. We will discuss the research process, its key steps and preliminary findings, as well as how inclusivity of participants was taken along throughout this process. The links between research design, designers and project participants are explored and reflected on. Our positions as researchers within the research process are also reflected upon. We will additionally address the implications of our research for the broader field of inclusive design for assistive robotics and the creative methodologies employed and tailored to the needs of families headed by parents with an ID and their children. In this, we keep a close eye on the difficulties such families face within the context of our research project. Lastly, we reflect on several key markers of collaboration within marginalised communities we encountered in our research.

This article recounts the history of electronic journals, and the evolution of library processes to manage them. The article reviews recent controversies regarding the future of electronic publishing, and describes one important and innovative electronic publisher, the Public Library of Science.

In this paper the co-authors, educators and organizers working together in a liberatory curriculum development organization (People's Education Movement Chicago), put forth a conceptualization of Critical Race Praxis (CRP) in education as it applies to K-12 curriculum and education writ large. They take Yamamoto's (1997) premise seriously in that they need to spend less time with abstract theorizing and more time in communities experiencing injustice.

The co-authors utilize critical race counterstory methodologies to analyze and (re)tell their experiences building and supporting justice-centered curriculum bound in CRP. In doing so, they share narratives that illuminate their individual and collective experiences navigating the gratuitous violence of white supremacy and other forms of structural oppression, and their work to center justice in and out of K-12 schools.

The findings provide examples of organizational praxes within the tenets of CRP (Conceptual, Material, Performative and Reflexive). For People’s Education Movement Chicago the conceptual conditions of their praxes begin with an intersectional analysis of schooling, education, and life. Within the CRP tenant of the material, the co-authors share experiences that detail their continuous political education and offer seven emergent ways of being and building to bound the material change they seek to create through their work. Next, the co-authors share their insights on the performative tenet, with a focus on curriculum, which creates learning experiences that support people to remember social movements and develop within them the curiosity and agency to act on their findings in ways that center justice and transformation. Finally, the findings related to reflexivity focus on the authors’ internal practices as a collective. The authors place process over product which, as they articulate, is a must if they are to produce a vital harvest for communities they work with and for.

The authors conclude the article with the following offerings useful to P-20 educators, researchers, school administrators and community members advancing more just educational futures: a commitment to the on the groundwork, situating social justice as an experiential phenomenon, the utilization of interdisciplinary approaches, collaborative work and capacity building, and a commitment to self and collective care.

As P-20 teachers, community workers, organizers, caregivers and education scholars of color building together in a K-12 curriculum development organization, the authors suggest that now is the moment to pivot away from the rhetoric of “we don't do CRT” and into work that constructs paths toward praxes bound in the tenets of CRP.

The aim of the study is to evaluate role of trade war between the United States and China on oil price. For this purpose, global oil price and US trade balance with China are selected as variables. In addition to this issue, monthly data of these variables for the periods between 1990 and 2019 are taken into consideration. In the evaluation process, both Engle–Granger cointegration and Toda–Yamamoto causality analysis are considered. The results of Engle–Granger cointegration analysis indicates that there is a ­relationship between trade war and oil prices. Nevertheless, according to the results of Toda–Yamamoto causality analysis, it is identified that trade war does not cause oil prices. While looking at these results, it is determined that trade war between the United States and China has an influence on the oil price changes. However, it is also understood that it is not the main factor of this volatility. Thus, it is recommended that in order to identify the main indicator of the oil price volatility, some different factors should also be taken into consideration.