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Fiber-reinforced armor-grade polymer-matrix composite materials with a superior penetration resistance are traditionally developed using legacy knowledge and trial-and-error empiricism. This approach is generally quite costly and time-consuming and, hence, new (faster and more economical) approaches are needed for the development of high-performance armor-grade composite materials. One of these new approaches is the so-called materials-by-design approach. Within this approach, extensive use is made of the computer-aided engineering (CAE) analyses and of the empirically/theoretically established functional relationships between an armor-grade composite-protected structure, the properties of the composite materials, material microstructure (as characterized at different length-scales) and the material/structure synthesis and fabrication processes. The paper aims to discuss these issues.

In the present work, a first step is made toward applying the materials-by-design approach to the development of the armor-grade composite materials and protective structures with superior ballistic-penetration resistance. Specifically, CAE analyses are utilized to establish functional relationships between the attributes/properties of the composite material and the penetration resistance of the associated protective structure, and to identify the combination of these properties which maximize the penetration resistance. In a follow-up paper, the materials-by-design approach will be extended to answer the questions such as what microstructural features the material must possess in order for the penetration resistance to be maximized and how such materials should be synthesized/processed.

The results obtained show that proper adjustment of the material properties results in significant improvements in the protective structure penetration resistance.

To the authors’ knowledge, the present work is the first reported attempt to apply the materials-by-design approach to armor-grade composite materials in order to help improve their ballistic-penetration resistance.

Polyurea is an elastomeric two-phase co-polymer consisting of nanometer-sized discrete hard (i.e. high glass transition temperature) domains distributed randomly within a soft (i.e. low glass transition temperature) matrix. A number of experimental investigations reported in the open literature clearly demonstrated that the use of polyurea external coatings and/or internal linings can significantly increase blast survivability and ballistic penetration resistance of target structures, such as vehicles, buildings and field/laboratory test-plates. When designing blast/ballistic-threat survivable polyurea-coated structures, advanced computational methods and tools are being increasingly utilized. A critical aspect of this computational approach is the availability of physically based, high-fidelity polyurea material models. The paper aims to discuss these issues.

In the present work, an attempt is made to develop a material model for polyurea which will include the effects of soft-matrix chain-segment molecular weight and the extent and morphology of hard-domain nano-segregation. Since these aspects of polyurea microstructure can be controlled through the selection of polyurea chemistry and synthesis conditions, and the present material model enables the prediction of polyurea blast-mitigation capacity and ballistic resistance, the model offers the potential for the “material-by-design” approach.

The model is validated by comparing its predictions with the corresponding experimental data.

The work clearly demonstrated that, in order to maximize shock-mitigation effects offered by polyurea, chemistry and processing/synthesis route of this material should be optimized.

The purpose of this study is to provide a novel multi-fingered hand made of hyperelastic material. This kind of hand has the advantage of less mechanical parts, simpler control system. It can greatly cut down the complexity and cost of the hands under conditions of ensuring enough flexibility of grasping.

Based on the principle of virtual work, the equations of pulling force and grasping force are derived. To get the max grasping force, the optimal structural dimensions of the hand are obtained by finite element simulations. Hand’s grasping experiment is conducted.

The factors influencing grasping force and grasping stability are identified, and they are the length between short poles around the knuckles and the height of short poles. Experimental results show that the max strain of knuckles is less than the elastic limit of hyperelastic material, and the presented hand is practicable. The adaptive ability and grasping stability of the presented hand are demonstrated.

A novel multi-fingered hand made of hyperelastic material is presented in this paper. By designing the thickness of every section of a hyperelastic plate, the knuckle sections will bend and other sections of the plate will remain straight, and thus, the multi-fingered hand will grasp.

The purpose of this paper is to present the results of an exploratory study that investigates Portuguese academics’ conceptions concerning the temporal properties of e-learning, in the context of traditional Higher Education Institutions.

Grounded Theory methodology was used to systematically analyse data collected in semi-structured interviews with 62 academics. Data analysis followed the constant comparative method and its three-staged coding approach: open, axial and selective coding. Data collection and analysis developed until theoretical saturation was reached.

Emergent academics’ conceptions concerning the temporal properties of e-learning indicate the existence of unregulated and unaccounted for dynamics, which are a direct consequence of transitioning from campus-based lecturing to teaching online using the affordances of virtual learning environments. This transition produces disruptions to established workload metrics and work patterns, as well as conflicts with dominant modes of instructional delivery that are not synchronised with the demands of online interaction and immediacy.

This paper is valuable to e-learning strategists and administrators. An understanding of the temporal properties of e-learning as perceived by academics provides actionable knowledge that is directly applicable to the design of suitable work arrangements, normative frameworks and e-learning practices that address perceived time-related barriers. To mitigate the time-related conflicts and disruptions identified in the study the authors suggest the establishment of university-wide norms of virtual presence and the implementation of temporal protocols to sustain the productive engagement between instructors and learners.

Drawing on the resource dependence theory (RDT), this paper investigates ownership composition, export intensity, and industry class as moderating factors to investigate the role of imported raw materials in performance of inward foreign direct investment (IFDI) in Ethiopia.

The hypotheses were tested using secondary data obtained from the 2016 Central Statistical Agency (CSA) on Large- and Medium-Scale Manufacturing and Electricity Industries Survey. The data included basic quantitative information on the country's manufacturing industry. The data items for the 2016 manufacturing and electricity industries surveyed are the numbers of proprietors or establishments involved in various sectors. The report did not record small firms that employed fewer than 10 people and did not use power-driven machinery. Two-Stage least squares (2SLS) regression analysis was performed to test the proposed hypotheses.

The results of this study indicate that three moderators (ownership composition, export intensity, and industry classification) interact with the hypothetical relationships between imported raw materials and performance. These findings enrich the knowledge of IFDI firms' operations in Ethiopia and in other least-developed countries (LDCs). The findings could provide information for IFDI firms that are looking to invest in LDCs.

Like all social science research, this study has some limitations. First, the research was conducted with the data found in the Report on Large- and Medium-Scale Manufacturing and Electricity Industries Survey In 2016. This was the first year of the second five-year Growth and Transformation Plan (GTP II), a national development plan for the 2016–2020 period. Continual research on IFDI in Ethiopia in the following years will be needed to get a full picture of the effects of the determinants on IFDIs.

To IFDI investors, the result of this thesis demonstrates several alternatives to overcoming hurdles in manufacturing operation. The results find that J.V. firms make better use of imported raw materials than W.O. subsidiaries in order to achieve better performance. Concerning the choice between focusing on export or domestic markets, the study suggests that domestic market—oriented companies require less imported raw materials to achieve better performance. Concerning the comparative advantage on different industries, this study found the performance of firms in Industry 12 depended on imported raw materials. These findings highlight the challenges and opportunities for potential foreign investors. Ownership composition, market factors, and industry factors should be well considered in making investment decisions.

This is one of few studies on IFDI in Ethiopia, the most populous LDC. Ownership composition, export intensity, and industry class are used as moderating variables to investigate the difference between imported raw materials and the level of expatriate deployment to IFDI performance. For IFDI investors, the results of this study demonstrate several alternatives to overcoming hurdles in manufacturing operation.

Composites are prime examples of technology moving faster than the underlying science. Faced with increasing global competitiveness, the issues of high cost, product robustness and long lead times associated with product development are emerging in the forefront of problems facing emerging and existing performance‐critical industries, such as in the area of advanced materials. However, the mere use of the new paradigms or philosophies, such as concurrent engineering, is insufficient to guarantee successful completion of the product realization process (PRP). Planning for competitiveness and quality as an integral part of the programme goals and decision process is a key to success. It is essential that clear plans be developed and measurable attributes of performance be identified as early in the design process as possible. The approach described herein provides the framework for successful implementation of an integrated decision‐production system within the basic definition of Total Quality Management (TQM). Discusses the five elements critical to the success of a new technology or product: definition; requirements; benchmarking; concepts; and review.

This paper reviews recent developments in marketing-related sustainable business practices (SBP) that macromarketing scholars have researched and debated for four decades. Such SBPs should be regarded as positive steps toward a future where business does more good than harm in society.

Using the approach of a literature review, this paper highlights the actions of entrepreneurs and firms to implement SBPs resulting from analysis of the interplay between markets, marketing and society. Such analysis is in the tradition of macromarketing scholarship.

The study identifies important developments about an important shift toward adopting SBPs among many firms, as well as among consumers − especially, in developed countries of the world.

The study suggests that taking a macromarketing view offers scholars a broad lens on current complex marketplace phenomena that will prove effective in better understanding sustainability issues.

The results of the study underline the value of macromarketing scholarship through the last four decades. By being daring enough to consider other stakeholders other than marketers and owners of firms, macromarketers have provided scholars a more holistic understanding of business’ role in society.

Today, enlightened practitioners who utilize knowledge from macromarketing scholarship can gain a competitive advantage as they navigate markets increasingly influenced by a wider set of stakeholders. Such influential stakeholders include partner firms, employees, society and local communities, NGOs, media, government, as well as the environment and future generations. Scholars can gain perspective on the phenomena they investigate with such a macromarketing lens.