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This paper develops the statistical error analysis model for assembling, to derive measures of controlling the geometric variations in assembly with multiple assembly stations, and to provide a statistical tolerance prediction/distribution toolkit integrated with CAD system for responding quickly to market opportunities with reduced manufacturing costs and improved quality. First the homogeneous transformation is used to describe the location and orientation of assembly features, parts and other related surfaces. The desired location and orientation, and the related fixturing configuration (including locator position and orientation) are automatically extracted from CAD models. The location and orientation errors are represented with differential transformations. The statistical error prediction model is formulated and the related algorithms integrated with the CAD system so that the complex geometric information can be directly accessed. In the prediction model, the manufacturing process (joining) error, induced by heat deformation in welding, is taken into account.

The aim of this study is to present design tactics (DTs) for supporting the adaptability of existing primary and middle school buildings into the emerging needs of coronavirus disease 2019 (COVID-19). The study introduces a novel algorithmic model for postoccupancy evaluation of the existing school buildings and provides solutions to enhance the adaptability of these buildings.

This study employs the DTs defined by the authors, integration of DTs to the algorithmic model and tests the usability of the proposed model in the selected sample set. The sample set consists of four primary and middle school buildings with different architectural qualities. The degrees of flexibility of the existing sample set are evaluated depending on the outcomes of the implementation.

The degrees of flexibility are achieved as a result of execution of the algorithmic model for each selected school building. Initial results of the case studies show that the flexibility of a school building is highly related to affordances and design decisions of the plan layout which were considered in the initial phases of the design process. Architectural qualities such as open plan and having sufficient voids in the interior and exterior space become prominent factors for ensuring flexibility.

Developing a systematic approach to the adaptation problem of primary and middle school buildings to postpandemic reuse is a novel research topic. Apart from this contextual originality, the proposed taxonomy for postpandemic reuse in terms of three levels of adaptation is a new conceptual framework. Moreover, the proposed algorithmic model itself can be considered as an original contribution, as well as a merge of qualitative values such as adaptation and flexibility with an algorithmic model.

A two‐dimensional model for hybrid circuits is presented in this paper. Simulation results of a hybrid power module for different power dissipation of components and ambient temperature are given. The experimental contribution is based on thermal measurements of the realized hybrid power module using a matrix of flip‐chip sensors. Thermal measurements were taken at different ambient temperatures and different hybrid module power values. The temperature distributions obtained theoretically and experimentally are compared and analyzed. Finally, the contribution of the temperature distributions and measured temperatures to the reliability of the hybrid power module is given.

In this chapter, we present our ongoing efforts in developing and sustaining interdisciplinary STEM undergraduate programs at North Carolina A&T State University (NCA&T) – a state-supported HBCU and National Science Foundation (NSF) Historically Black Colleges and Universities Undergraduate Program (HBCU-UP) Institutional Implementation Project grantee. Through three rounds of NSF HBCU-UP implementation grants, a concerted effort has been made in developing interdisciplinary STEM undergraduate research programs in geophysical and environmental science (in round 1), geospatial, computational, and information science (in round 2), and mathematical and computational biology (in round 3) on NCA&T campus. We first present a brief history and background information about the interdisciplinary STEM undergraduate research programs developed and sustained at NCA&T, giving rationales on how these programs had been conceived, and summarizing what have been achieved. Next we give a detailed description on the development of undergraduate research infrastructure including building research facilities through multiple and leveraged funding sources, and engaging a core of committed faculty mentors and research collaborators. We then present, as case studies, some sample interdisciplinary research projects in which STEM undergraduate students were engaged and project outcomes. Successes associated to our endeavor in developing undergraduate research programs as well as challenges and opportunities on implementing and sustaining these efforts are discussed. Finally, we discuss the impact of well-structured undergraduate research training on student success in terms of academic performance, graduation rate and continuing graduate study, and summarize many of the learnings we have gained from implementation and delivery of undergraduate research experiences at HBCUs.

Design and build (D/B) construction methods have gained more importance in recent years for their potential advantages in improving project performance. There are, however, a number of problems that are commonplace in D/B procurement, which, when they interact with each other, can lead to project time and cost overrun problems. The most important among them are design changes, together with communication and coordination lapses among concerned parties. Past research has focused only on the characteristics of the traditional construction, or separate sub‐systems such as different phases or human resource input to projects. An attempt is made in this paper to improve D/B project time and cost performance. A generic system dynamics model is developed that incorporates major sub‐systems and their relationships inherent in D/B constructions projects. It is validated and calibrated for a typical large D/B infrastructure project using time and cost overrun problems experienced in Thailand. Extensive simulations with many policies, individually or in various combinations, show that improvement in time or cost can be made with proper policy combinations that reflect strong interactions between the whole design and build system and can be derived only if these interactions are accounted for. To achieve overall improvement in both time and cost, the combination of full overtime schedule, average material ordering, and fast track construction with moderate crashing of design is most appropriate. If cost is the focus, extending the construction schedule, combined with material ordering based on actual need, and design and build with traditional construction method is the best solution.

Auxetic structures are one type of mechanical meta-materials mainly used for energy absorption applications because of their unique negative Poisson’s ratio. This study is focused on numerical and experimental investigations of fused deposition modeling (FDM) fabricated re-entrant auxetic structures of acrylonitrile butadiene styrene (ABS) and poly-lactic acid (PLA) materials under compressive loading. Influence of geometric parameters, namely, re-entrant angle, height and arm-length on strength, stiffness and specific energy absorption (SEA) of auxetic structures under compressive loading. Optimization of significant parameters is also performed to maximize these responses and minimize weight and time of fabrication. Further, efforts have also been made to develop predictive models for strength, stiffness and SEA of auxetic structures.

A full factorial design of experiment is used for planning experiments. Auxetic structures of ABS and PLA are fabricated by FDM technique of additive manufacturing within the constrained range of geometric parameters. Analysis of variance is performed to identify the influence of geometric parameters on responses. To optimize the geometric parameters Gray relational analysis is used. Deformation of auxetic structures is studied under compressive loading. A numerical investigation is also performed by building nonlinear finite element models of auxetic structures.

From the analysis of results, it is found that re-entrant angle, height and arm-length with their interactions are significant parameters influencing responses, namely, strength, stiffness and SEA of the auxetic structures of ABS and PLA materials. Based on the analysis, statistical nonlinear quadratic models are developed to predict these responses. Optimal configurations of auxetic structure of ABS and PLA are determined to maximize strength, stiffness, SEA and minimize weight and time of fabrication. From the study of deformation of auxetic structures, it is found that ABS structures have higher energy absorption, whereas PLA structures have better stiffness. Results of finite element analysis (FEA) are found in good agreement with experimental results.

The present study is limited to re-entrant type of auxetic structures of ABS and PLA materials only under compressive loading. Also, results from the present study are valid within the selected range of geometric parameters. The findings of the present study are useful in maximizing strength, stiffness and SEA of auxetic structures that have wide applications in the automotive, aerospace, sports and marine sector.

No literature is available on studying the influence of geometric parameters, namely, re-entrant angle, height and arm-length of auxetic structure on strength, stiffness and SEA under compressive loading. Also, a comparative study of feedstock materials, namely, ABS and PLA, is also not reported. The present work attempts to fulfill the above research gaps.

Sustainable supplier selection is of vital importance in sustainability decision of supply chain under carbon neutrality. Multi-criteria decision-making approaches are widely used in sustainable supplier selection and generally classified the involved criteria into three sustainable development (SD) dimensions: Environmental, Social and Economic. During the assignment of appropriate weighted scores to the criteria, most of the methods considered mutually exclusive criteria. However, some criteria cover multidimensions since ambiguity vagueness makes them difficult to classify into one dimension exclusively. The purpose of this paper is to find proper approaches addressed to multidimensional overlapping criteria in the evaluation of suppliers’ sustainability performance.

This study proposes three approaches to resolve the multidimensional overlapping criteria issue by data envelopment analysis (DEA) methods. The first approach uses all dimensional criteria and “dimensional overlapping criteria” in a single DEA model. The second approach consists of two-stage DEA. The first stage is to find SD dimensional performances, which are used in the second stage. The third approach uses an aggregate weight-constrained DEA model with additional constraints. Such approaches are applied to an empirical case study with six dimensions.

Results indicate that the third approach is better than the first two approaches in balancing the development among all dimensions instead of focusing on the superiority dimension to obtain high performance.

Discussing overlapping criteria in the context of sustainable supplier evaluation and other multi-criteria evaluation have a noticeable impact on evaluation systems, but appropriate approaches for this issue are currently under-researched.

The paper's purpose is to promote the use of modern technologies such as multimedia packages to engineering students. The aim is to help them to learning in their learning, visualization, problem solving and understanding engineering concepts such as in mechanics dynamics.

TAPS packages are developed to help students solve selected engineering problems in a step‐by‐step approach. A comparison is made with existing commercial engineering packages to see if TAPS packages could further enhance the learning process.

The differences found were indicative of better presentation and clarity, step‐by‐step approach to solve engineering problems, user‐friendly environment, unbiased assessment of performance and flexibility to incorporate 3‐D geometric models in the TAPS packages.

The TAPS packages were compared with two commercial engineering packages and were based on a small number of users. A larger sample size of students would be required to see if TAPS packages are productive enough to be used locally in Malaysian universities and higher learning institutions.

The main originality of the paper can be seen from the development of the TAPS packages and the comparative study with existing commercial engineering packages. The differences found are explained in details in this paper.

The purpose of this study is to develop a novel mechanical flux-weakening topology for the switched flux permanent magnet (SFPM) machine to extend the speed range, which will be suitable for the electric vehicles and hybrid electric vehicles.

The 3 dimensional mechanical flux-weakening model with flux adjusters (FAs) in the end-cap is established. Subsequently, the electromagnetic performance is compared between the SFPM machine with FAs in the end-cap and without FAs. The open circuit flux-linkage is calculated by finite element analysis (FEA) to investigate the influence of this mechanical flux-weakening topology together with the d/q-axis inductance. The flux-weakening capability and torque-speed curve is also calculated.

The proposed topology decreases the permanent magnet flux-linkage and increases the d-axis inductance, which improve the flux-weakening capability simultaneously. Subsequently, the speed range and constant power region are much wider than those without FAs. Finally, the prototype is fabricated and the measured result of the open circuit back electromotive force has good agreement with the FEA result.

This paper provides a novel mechanical flux-weakening topology with FAs in the end-cap for the SFPM machine, whose volume is smaller than another mechanical flux-weakening topology with FAs at the stator outside. Thus, higher torque and power density can be obtained compared with the SFPM machine with FAs at the stator outside.