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The purpose of this paper is to propose physically based varying fidelity surrogates to be used in structural design optimization of space trusses. The main aim is to demonstrate its efficiency in reducing the number of high fidelity (HF) runs in the optimization process.

In this work, surrogate models are built for space truss structures. This study uses functional as well as physical surrogates. In the latter, a grid analogy of the space truss is used thereby reducing drastically the analysis cost. Global and local approaches are considered. The latter will require a globalization scheme (sequential approximate optimization (SAO)) to ensure convergence.

Physically based surrogates were proposed. Classical techniques, namely Taylor series and kriging, are also implemented for comparison purposes. A parameter study in kriging is necessary to select the best kriging model to be used as surrogate. A test case was considered for optimization and several surrogates were built. The CPU time is reduced when compared with the HF solution, for all surrogate‐based optimization performed. The best result was achieved combining the proposed physical model with additive corrections in a SAO strategy in which C1 continuity was imposed at each trust region center. Some guidance for other engineering applications was given.

This is the first time that physical‐based surrogates for optimum design of space truss systems are used in the SAO framework. Physical surrogates typically exhibit better generalization properties than other surrogates forms, produce faster solutions, and do not suffer from dimensionality curse when used in approximate optimization strategies.

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.

In order to increase productivity and create added value in ceramic and tile industries of Iran, the role of physical assets including machinery, equipment and utilities is very important in these industries, and management of those take an important role. Organizational culture and its role in physical asset management implementation are very important in the Iran ceramic and tile industries. In these industries, there is a secret force called culture, which must be changed if the organization wants to grow up and improve physical assets management. The purpose of this paper is to identify organizational cultural, technical and reliability variables and structure of these variables in form of a combined structural model.

In order to present a structural combination model, a development model type, the mixed research method is used, and expert’s comments are also used. This model was implemented at Apadana Ceram Company, and its results, in comparison with previous models on physical assets, have shown that consideration of four culture elements can be of great help to reach an optimal point in maintenance and excellence.

In this paper, analysis of previous research studies, project documents and expert’s opinions in ceramic and tile industries have been used. In the presented model, special attention has been paid to organizational culture and its four elements including values, patterns, rituals and procedures and cultural infrastructure in order to achieve excellence and reach an optimal point in maintenance. Also, governing structure between organizational culture and technical and reliability variables was nominated, which could help companies in physical asset management. Furthermore, eight components of change management were expressed, which are important in order to implement this model.

This model with special consideration of four culture elements can be of great help to industries to reach an optimal point in maintenance and excellence.

Improperly fitted parameters for the Jiles–Atherton (JA) hysteresis model can lead to non-physical hysteresis loops when ferromagnetic materials are simulated. This can be remedied by including a proper physical constraint in the parameter-fitting optimization algorithm. This paper aims to implement the constraint in the meta-heuristic simulated annealing (SA) optimization and Nelder–Mead simplex (NMS) algorithms to find JA model parameters that yield a physical hysteresis loop. The quasi-static B(H)-characteristics of a non-oriented (NO) silicon steel sheet are simulated, using existing measurements from a single sheet tester. Hysteresis loops received from the JA model under modified logistic function and piecewise cubic spline fitted to the average M(H) curve are compared against the measured minor and major hysteresis loops.

A physical constraint takes into account the anhysteretic susceptibility at the origin. This helps in the optimization decision-making, whether to accept or reject randomly generated parameters at a given iteration step. A combination of global and local heuristic optimization methods is used to determine the parameters of the JA hysteresis model. First, the SA method is applied and after that the NMS method is used in the process.

The implementation of a physical constraint improves the robustness of the parameter fitting and leads to more physical hysteresis loops. Modeling the anhysteretic magnetization by a spline fitted to the average of a measured major hysteresis loop provides a significantly better fit with the data than using analytical functions for the purpose. The results show that a modified logistic function can be considered a suitable anhysteretic (analytical) function for the NO silicon steel used in this paper. At high magnitude excitations, the average M(H) curve yields the proper fitting with the measured hysteresis loop. However, the parameters valid for the major hysteresis loop do not produce proper fitting for minor hysteresis loops.

The physical constraint is added in the SA and NMS optimization algorithms. The optimization algorithms are taken from the GNU Scientific Library, which is available from the GNU project. The methods described in this paper can be applied to estimate the physical parameters of the JA hysteresis model, particularly for the unidirectional alternating B(H) characteristics of NO silicon steel.

The purpose of this paper is to assess the relative importance of various service‐quality dimensions in explaining customer satisfaction; and to examine whether this assessment is affected by the measurement instrument that is used.

A new (“servicescape”) model for directly measuring the physical and the interactive features of a service is proposed and tested against the SERVQUAL measurement model and Nordic conceptualisation. Data are collected from a structured questionnaire survey of 434 passengers at the port of Piraeus in Greece.

The findings reveal that the widely used SERVQUAL instrument fails to fully capture the role of “tangibles” in determining overall customer satisfaction in the service under examination. The new proposed “servicescape model” attaches more importance to the role of physical environmental attributes than has been reported in most previous studies.

Service providers should pay more attention to the physical environment in which they are operating. They should also note that different measurement instruments provide different results.

This paper proposes and tests a new (“servicescape”) measuring instrument that has not been previously developed or operationalised.

The purpose of this paper is to give a comprehensive survey on the physics-based virtual assembly (PBVA) technology in a novel perspective, to analyze current drawbacks and propose several promising future directions.

To provide a deep insight of PBVA, a discussion of the developing context of PBVA and a comparison against constraint-based virtual assembly (CBVA) is put forward. The core elements and general structure are analyzed based on typical PBVA systems. Some common key issues as well as common drawbacks are discussed, based on which the research trend and several promising future directions are proposed.

Special attention is paid to new research progresses and new ideas concerning recent development as well as new typical systems of the technology. Advantages of PBVA over CBVA are investigated. Based on the analysis of typical PBVA systems and the evolution of PBVA, the core elements of the technology and the general structure of its implementation are identified. Then, current PBVA systems are summarized and classified. After that, key issues in the technology and current drawbacks are explored in detail. Finally, promising future directions are given, including both the further perfecting of the technology and the combination with other technologies.

The PBVA technology is put into a detailed review and analysis in a novel way, providing a better insight of both the theory and the implementation of the technology.

The purpose of this paper is to determine the extent to which team processes vary between team types, as well as the relative importance of these processes for different team types.

A survey study evaluated a sample of 316 members of various work teams that were classified as either intellectual (e.g. executive team) or physical (e.g. production team) teams. Independent samples t‐tests, paired samples t‐tests, and confirmatory factor analysis were used to evaluate hypotheses.

Confirmatory analysis indicated transition and action oriented process behaviors were distinct from one another. Intellectual teams were found to value transition processes (planning and strategizing) more highly than physical teams. Intellectual teams also valued transition processes (planning and strategizing), more than action processes (monitoring and coordinating).

Research on team processes tends to focus upon a “one size fits all” approach to teamwork, but this approach has yielded inconsistent frameworks. This study provides evidence that these inconsistencies are due to the changing nature of teamwork. This study was limited in that only two broad types of teams and two types of process competencies were assessed.

Differences in the importance of certain processes for specific team types should be taken into account when implementing systems for team selection, performance appraisal, and training.

This paper provides empirical support for previous theoretical suppositions that different team types differ in the level of importance they place on certain processes.

This paper aims to present a method of reproducing multi-object structures from materials of diverse physical properties with the use of models fabricated by means of rapid prototyping (RP) techniques.

A process of modelling complex anatomical structures of soft tissues and bones using mandible models as examples was described. The study is based on data acquired through standard computed tomography. Physical models of examined objects were fabricated with RP technology from a 3D-CAD virtual model.

In the analysis of complex medical issues, beside numerical methods, one can simultaneously make use of experimental tests to verify obtained results. In the case of experimental tests, it is necessary to fabricate physical models with appropriate material properties. RP techniques used in the method ensure accurate reproduction of the external shape of the fabricated model, whereas consecutive stages allow us to construct moulds and create internal structures within a finished model by wax cast models.

The application of a physical RP model makes the identification of medical problem more efficient and the reconstruction of pathological alterations for experimental tests clearer. It prevents the simplification of assumptions to experimental analysis. The approach may reduce costs of fabricating models for experimental studies and offers the possibility of using materials of desired properties.

The approach developed by the authors and presented in this paper was submitted for patent protection as “A Method of Reconstructing Medical Models with Internal Structure and the Use of Materials of Diverse properties” – patent application no. P.398644.

The disruption global digitally based firms are imposing on the positions of established multinational telcos is not just in degree, but also in kind. As such, the telcos are entering a period of VUCA. Although digitally based competitors could suffer from liabilities of “outsidership,” we argue that the physical presence of telcos in local markets will be insufficient to avoid a future as utilities or dumb-pipes. One significant issue as they confront VUCA is therefore whether telcos are able to develop and apply dynamic capabilities.

The purpose of this paper is to present the results of an analytical and experimental research for the development of an innovative product designated RFID environment (RFID‐Env). This software is designed for the use of professionals in computer systems and plant engineering who are engaged in research and development (R&D) of ultra high frequency (UHF) passive radio frequency identification (RFID) systems as applied to the management and operation of logistic supply chains.

The RFID‐Env makes it possible to simulate on computer screens a complete RFID‐Env by processing user data on the technical and physical characteristics of real or virtual RFID‐Envs. Information outputted can include descriptions of the performance to be expected from a given configuration and detailed reports as to whether that particular configuration will succeed in reading all the RFID tags flowing through a defined system.

The paper shows the models and methods on how these simulations can be performed, and this is the major scientific contribution of this work, i.e. what are the logical and physical models that enable the development of software simulators for RFID‐Envs.

This work will be continued to introduce more consideration of the physical environment, such as the interferences produced by the tagged products themselves by scattering the radio frequency (RF) signals, and the models, positioning and focusing of the antennas. New RF prediction models shall be created along the continuation of this paper, with the purpose to rise the amount of environments that can be simulated.

The product is intended for use by developers in computer sciences, and by engineers doing R&D for the solution of RFID problems, and makes it possible to simulate a complete range of virtual RFID‐Envs so that R&D can proceed in a non‐factory atmosphere.

There are only a few related papers that consider in an isolated form some of the problems approached here, but it was not found models that proposed as an integrated form all the processing to an RFID‐Env simulation like here presented.