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For part models with complex shape features or freeform shapes, the existing build orientation determination methods may have issues, such as difficulty in defining features and costly computation. To deal with these issues, this paper aims to introduce a new statistical method to develop fast automatic decision support tools for additive manufacturing build orientation determination.

The proposed method applies a non-supervised machine learning method, K-Means Clustering with Davies–Bouldin Criterion cluster measuring, to rapidly decompose a surface model into facet clusters and efficiently generate a set of meaningful alternative build orientations. To evaluate alternative build orientations at a generic level, a statistical approach is defined.

A group of illustrative examples and comparative case studies are presented in the paper for method validation. The proposed method can help production engineers solve decision problems related to identifying an optimal build orientation for complex and freeform CAD models, especially models from the medical and aerospace application domains with much efficiency.

The proposed method avoids the limitations of traditional feature-based methods and pure computation-based methods. It provides engineers a new efficient decision-making tool to rapidly determine the optimal build orientation for complex and freeform CAD models.

This paper aims to introduce a new nesting scheme to better describe and solve the single-layer-part packing problem in additive manufacturing (AM).

Parallel nesting scheme using two-dimensional (2D) changeable projection profiles is developed. At first, a feature-based orientation optimization method is used to identify a set of practical alternative build orientations for each part to ensure the part quality. Then, 2D polygons are used to represent each part’s projection profiles under its alternative build orientations. Finally, a parallel layout searching algorithm is developed to identify the optimal part layout by using 2D changeable projection profiles.

The proposed nesting scheme can both guarantee the production quality for each part and search the optimal part layout with larger probability but less computational time.

With the use of changeable 2D projection profiles, this method conducts 2D computation to solve the single-layer-part packing problem with five degrees of freedom, which saves much computation cost and, at the same time, guarantees the production quality of each part. By adding specific nesting objectives or constraints and heuristic searching knowledge to the proposed nesting scheme, practical nesting software can be developed to meet the specific nesting or packing requirements for industrial AM machines.

Rapid prototyping systems are controlled by a computer which uses the CAD representation to build parts according to an additive plane layering process. The computer controls a laser beam or a print head, or any process that leads to the formation of a slice of a part using resins, powders, paper, wax or other materials. The original CAD representation is translated into commands to drive the process, and accuracy issues will make or break these emerging technologies. It is therefore important to understand where the errors stem from, what are the issues associated with the software representation formats, and how to minimize or eliminate these errors. Presents a summary of CAD to RP software formats, and explains the accuracy issues associated with the selected representation. Discusses improvements that can be obtained by process modifications.

The purpose of this paper is to focus on the changing dynamics of the ultrasonic consolidation (UC) process due to changes in substrate geometry. Past research points to a limiting height to width ranging from 0.7 to 1.2 on build features.

Resonances of a build feature due to a change in geometry are examined and then a simple non‐linear dynamic model of the UC process is constructed that examines how the geometry change may influence the overall dynamics of the process. This simple model is used to provide estimates of how substrate geometry affects the differential motion at the bonding interface and the amount of energy emitted by friction change due to build height. The trends of changes in natural frequency, differential motion, and frictional energy are compared to experimental limits on build height.

The paper shows that, at the nominal build, dimensions of the feature the excitation caused by the UC approach two resonances in the feature. In addition trends in regions of changes of differential motion, force of friction, and frictional energy follow the experimental limit on build height.

This paper explores several aspects of the UC process not currently found in the current literature: examining the modal properties of build features, and a lumped parameter dynamic model to account for the changes in of the substrate geometry.

An adaptive slicing algorithm that can vary the layer thickness in relation to local geometry is presented. The algorithm is based on three fundamental concepts: choice of criterion for accommodating complexities of surfaces, recognition of key characteristics and features of the object, and development of a grouping methodology for facets used to represent the object. Four criteria, cusp height, maximum deviation, chord length and volumetric error per unit length, are identified and the layer thickness is adjusted such that one of the four is met. Next, key characteristics of the object, such as horizontal and vertical surfaces, pointed edges and ends, are identified based on the local changes in surface complexity, and slice based feature recognition is introduced to identify the nature of a feature, protrusion or depression, by studying the slice data. Note that the present approach uses information only from the tessellated model, and thus is different from current implementations. Finally, the concept of grouping of the facets based on their vertex coordinates is developed to minimize the number of searches for possible intersection of the facets with a slice plane. The slicing algorithm is interfaced with adaptive laminated machining and the stereolithography process through a CNC post processor and a hatching algorithm respectively. A comparison of the estimated surface quality and build time indicates that adaptive slicing produces superior parts in a shorter build time. The implementation of this work is protected under US Patent laws (Patent # 5,596,504, January 1997).

This paper presents the design of a 3 degrees of freedom build platform for a Stereo‐lithography Apparatus machine (older model without Zephyr coating). The Pahl and Beitz methodology is used to systematically design such a component. The various steps are illustrated and the final design described. The impetus for the research is the need to reduce layering errors in layer‐based machines. The final solution allows the platform to rotate along two axes and be elevated along the Z‐axis with minimal disruption to the present set‐up.

The impact of stress on personal and work-related outcomes has been studied in the information systems (IS) literature across several professions. However, the cybersecurity profession has received little attention despite numerous reports suggesting stress is a leading cause of various adverse professional outcomes. Cybersecurity professionals work in a constantly changing adversarial threat landscape, are focused on enforcement rather than compliance, and are required to adhere to ever-changing industry mandates – a work environment that is stressful and has been likened to a war zone. Hence, this literature review aims to reveal gaps and trends in the current extant general workplace and IS-specific stress literature and illuminate potentially fruitful paths for future research focused on stress among cybersecurity professionals.

Using the systematic literature review process (Okoli and Schabram, 2010), the authors examined the current IS research that studies stress in organizations. A disciplinary corpus was generated from IS journals and conferences encompassing 30 years. The authors analyzed 293 articles from 21 journals and six conferences to retain 77 articles and four conference proceedings for literature review.

The findings reveal four key research opportunities. First, the demands experienced by cybersecurity professionals are distinct from the demands experienced by regular information technology (IT) professionals. Second, it is crucial to identify the appraisal process that cybersecurity professionals follow in assessing security demands. Third, there are many stress responses from cybersecurity professionals, not just negative responses. Fourth, future research should focus on stress-related outcomes such as employee productivity, job satisfaction, job turnover, etc., and not only security compliance among cybersecurity professionals.

This study is the first to provide a systematic synthesis of the IS stress literature to reveal gaps, trends and opportunities for future research focused on stress among cybersecurity professionals. The study presents several novel trends and research opportunities. It contends that the demands experienced by cybersecurity professionals are distinct from those experienced by regular IT professionals and scholars should seek to identify the key characteristics of these demands that influence their appraisal process. Also, there are many stress responses, not just negative responses, deserving increased attention and future research should focus on unexplored stress-related outcomes for cybersecurity professionals.

Additive manufacturing of concrete (AMoC) is an emerging technology for constructing buildings. However, due to the nature of the concrete property and constructing buildings in layers, constraints and limitations are encountered while applying AMoC in architecture. This paper aims to analyze the constraints and limitations that may be encountered while using AMoC in architecture.

A descriptive research approach is used to conduct this study. First, basic notions of AMoC are introduced. Then, challenges of AMoC, including hardware, material property, control and design, are addressed. Finally, strategies that may be used to overcome the challenges are discussed.

Factors influencing the success of AMoC include hardware, material, control methods, manufacturing process and design. Considering these issues in the early design phase is crucial to achieving a successful computer-aided design (CAD)/computer-aided manufacturing (CAM) integration to bring CAD and CAM benefits into the architecture industry.

In three-dimensional (3D) printing, objects are constructed layer by layer. Printing results are thus affected by the additive method (such as toolpath) and material properties (such as tensile strength and slump). Although previous studies attempt to improve AMoC, most of them focus on the manufacturing process. However, a successful application of AMoC in architecture needs to consider the possible constraints and limitations of concrete 3D printing. So far, research on the potential challenges of applying AMoC in architecture from a building lifecycle perspective is still limited. The study results of this study could be used to improve design and construction while applying AMoC in architecture.

This chapter contextualizes futuristic learning in a distance education (DE) context for empowering and transforming students. Futuristic learning involves a continuous progress to higher levels of critical and creative thinking in a collaborative environment of academic freedom. Futuristic learning encourages classroom engagement and learning to students to use modern and advanced approaches of teaching and learning. The skills acquired should facilitate students’ intellectual, social, and emotional development. Futuristic pedagogy advocates the acquisition of systematized knowledge and skills and encourages the idea of engaging analytical and practical skills during learning. The chapter describes a practice that provides educational opportunities to a large section of students who study alone most of the time but get the opportunity of learning at organized tutorial sessions. This teaching approach may be the most viable option to mobilize futuristic learning in South Africa. A descriptive research methodology employed literature analysis of documents using data extracted from secondary sources of information, which entailed peer reviewed journal articles and books published between 2000 and 2018. A key finding is that the traditional form of education should pave way for futuristic pedagogy to allow schools to respond to the learning needs of students. The significance of the study is that it will offer opportunities for the change in learning approach to organize how student engagement will be carried out in the future. Informed by this finding futuristic learning should be committed to the provision of quality education to all DE students.

This chapter covers a full picture of the remaining chapters. The first part discusses the gap in the literature and the main objectives of this book. The next section overviews the book's design and methodology which includes the conceptual model, the research design and the research methodology. The final section in this chapter is the book's theoretical and practical contributions.