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2021 ◽  
pp. 135-150
Author(s):  
Krisztián Kis

It can be stated that quality is a multifaceted concept, and it makes the difference between any perceivable or conceivable entities visible. The meaning of quality has greatly changed over the years, its content has expanded and quality has become the most important single factor for success. Therefore, it is no exaggeration to say that “quality means business”. However, quality, as it will be seen, means much more than that. Corporate Social Responsibility and the service of Sustainable Development Goals have become part of organisational quality. Nonetheless, without innovation, there is no quality or competitiveness, thus, there is no business either. This is the 21st century, which, according to Joseph M. Juran, will be the century of quality. It is important to note that companies are not just economic units or merely market participants, but also social factors and entities influencing the environment. For this reason, compliance with social norms and ethical expectations is also an important aspect of their operation. To meet the expected and latent needs of customers and users, and also the requirements of society as well as the natural environment in a way that all stakeholders are equally satisfied is a fundamental issue for companies, today and even more so in the future. The main purpose of this chapter is to discuss how quality should be understood, and what the relationships between the issues involved are. In the chapter, it is argued that quality, Corporate Social Responsibility, innovation, competitiveness and sustainable development are interrelated concepts. Therefore, it is the further purpose of this chapter to discuss how social responsibility and innovation affect quality, and how quality contributes to competitiveness and sustainable development. In this chapter, quality issues are dealt with from different aspects. In the first part, the concept of quality is presented, which deals with the evolving notion of quality and the future of quality in light of social responsibility. In the second part, complexity issues and emergences are introduced, while quality is discussed as an emergent property, and the role played by social responsibility and environmental concerns in competitiveness and sustainable development are explained, and furthermore, innovation from quality and responsibility perspectives are examined.


2021 ◽  
Author(s):  
MEGAN SHEPHERD ◽  
KAMRAN MAKARIAN ◽  
GIUSEPPE PALMESE ◽  
NICHOLAS BRUNSTAD ◽  
LESLIE LAMBERSON

This study explores the role of rubber toughening on the dynamic fracture behavior of additively manufactured (AM) high-performance thermosetting polymers formed through digital light processing (DLP). Using DLP to create these polymers allows for rapid, agile manufacturing of prototypes meeting the lightweight and building speed requirements of relevance to military mission applications. This method also provides flexibility in part complexity while maintaining relatively high isotropy compared to traditional AM techniques. Previous work has demonstrated a dependence of these DLP specimens on print layer orientation and loading rate, prompting further investigation into other manufacturing parameters to improve toughness [1]. This study examines the role of rubber toughening on the quasi-static and dynamic fracture behavior of bis-GMA thermosets. Current literature largely reports on quasi-static behavior of DLP specimens, although dynamic conditions are more applicable to many realistic loading scenarios and extreme environments often seen in defense applications. Dynamic experiments leverage a unique long bar striker device that impacts a specimen opposite a pre-crack, sending a stress-wave driven load to initiate a dynamic Mode-I (opening) fracture event. Full-field displacement data ahead of the propagating crack is obtained using ultra high-speed imaging combined with 2D digital image correlation (DIC). An elastodynamic solution following the principles of dynamic fracture mechanics extracts the stress intensity factor (SIF) using a least squares fit at crack initiation and a Newton-Raphson scheme for crack propagation. The rubber toughened thermosets in this study exhibited a rate dependence in fracture toughness with the quasi-static SIF being 1.20 MPa and the dynamic SIF being 0.41 MPa .


2020 ◽  
Vol 12 (19) ◽  
pp. 7936 ◽  
Author(s):  
Abdullah Alfaify ◽  
Mustafa Saleh ◽  
Fawaz M. Abdullah ◽  
Abdulrahman M. Al-Ahmari

The last few decades have seen rapid growth in additive manufacturing (AM) technologies. AM has implemented a novel method of production in design, manufacture, and delivery to end-users. Accordingly, AM technologies have given great flexibility in design for building complex components, highly customized products, effective waste minimization, high material variety, and sustainable products. This review paper addresses the evolution of engineering design to take advantage of the opportunities provided by AM and its applications. It discusses issues related to the design of cellular and support structures, build orientation, part consolidation and assembly, materials, part complexity, and product sustainability.


2020 ◽  
Vol 6 (1) ◽  
pp. 148-163 ◽  
Author(s):  
Stefan Buijsman ◽  
Markus Pantsar

An important paradigm in modeling the complexity of mathematical tasks relies on computational complexity theory, in which complexity is measured through the resources (time, space) taken by a Turing machine to carry out the task. These complexity measures, however, are asymptotic and as such potentially a problematic fit when descriptively modeling mathematical tasks that involve small inputs. In this paper, we argue that empirical data on human arithmetical cognition implies that a more fine-grained complexity measure is needed to accurately study mental arithmetic tasks. We propose a computational model of mental integer addition that is sensitive to the relevant aspects of human arithmetical ability. We show that this model necessitates a two-part complexity measure, since the addition tasks consists of two qualitatively different stages: retrieval of addition facts and the (de)composition of multidigit numbers. Finally, we argue that the two-part complexity measure can be developed into a single response-time measure with the help of empirical study of the two stages.


2020 ◽  
Vol 994 ◽  
pp. 213-220
Author(s):  
Dávid Michal ◽  
Róbert Hrušecký ◽  
Peter Košťál ◽  
Ivan Molnár

The article is about manufacturing a component with a precision circular hole by Digital Light Processing (DLP) additive technology for inserting another part. The accuracy of the hole itself depends on the choice of production technology and the appropriate material. Deformation of the inner wall of the hole prevents correct insertion of the part - nut of trapezoidal threaded rod. This article analyzes the feasibility of manufacturing a component using Digital Light Processing (DLP) additive technology and the use of liquid resin „Proto GRY“ for the manufacture a component. Among additive technologies processes, digital light processing (DLP) is typically seen as the technology capable of reaching the highest standards in terms of part complexity and precision. DLP technology rely on the use of light, typically in the UV region of the spectrum (380 – 405 nm), to cure a photosensitive viscous resin. This resin, typically composed of epoxy or acrylic and methacrylic monomers, will polymerize and harden when exposed to light. As light shines on the vat to create specific shapes or patterns that compose each layer, a solid object can be formed and extracted from the otherwise liquid resin.


2020 ◽  
Vol 142 (9) ◽  
Author(s):  
Rohan Prabhu ◽  
Scarlett R. Miller ◽  
Timothy W. Simpson ◽  
Nicholas A. Meisel

Abstract Additive manufacturing (AM) enables engineers to improve the functionality and performance of their designs by adding complexity at little to no additional cost. However, AM processes also exhibit certain unique limitations, such as the presence of support material. These limitations must be accounted for to ensure that designs can be manufactured feasibly and cost-effectively. Given these unique process characteristics, it is important for an AM-trained workforce to be able to incorporate both opportunistic and restrictive design for AM (DfAM) considerations into the design process. While AM/DfAM educational interventions have been discussed in the literature, few studies have objectively assessed the integration of DfAM in student engineering designers’ design outcomes. Furthermore, limited research has explored how the use of DfAM affects the students’ AM designs’ achievement of design task objectives. This research explores this gap in literature through an experimental study with 301 undergraduate students. Specifically, participants were exposed to either restrictive DfAM or dual DfAM (both opportunistic and restrictive) and then asked to participate in a design challenge. The participants’ final designs were evaluated for (1) build time and build material (2) the use of the various DfAM concepts, and (3) the features used to manifest these DfAM concepts. The results show that the use of certain DfAM considerations, such as part complexity, number of parts, support material mass, and build plate contact area (corresponding to warping tendency), correlated with the build material and build time of the AM designs—minimizing both of which were objectives of the design task. The results also show that introducing participants to opportunistic DfAM leads to the generation of designs with higher part complexity and lower build plate contact area but a greater presence of inaccessible support material.


2020 ◽  
Vol 10 (3) ◽  
pp. 1100 ◽  
Author(s):  
Samyeon Kim ◽  
Seung Ki Moon

Parts with complex geometry have been divided into multiple parts due to manufacturing constraints of conventional manufacturing. However, since additive manufacturing (AM) is able to fabricate 3D objects in a layer-by-layer manner, design for AM has been researched to explore AM design benefits and alleviate manufacturing constraints of AM. To explore more AM design benefits, part consolidation has been researched for consolidating multiple parts into fewer number of parts at the manufacturing stage of product lifecycle. However, these studies have been less considered product recovery and maintenance at end-of-life stage. Consolidated parts for the manufacturing stage would not be beneficial at end-of-life stage and lead to unnecessary waste of materials during maintenance. Therefore, in this research, a design method is proposed to consolidate parts for considering maintenance and product recovery at the end-of-life stage by extending a modular identification method. Single part complexity index (SCCI) is introduced to measure part and interface complexities simultaneously. Parts with high SCCI values are grouped into modules that are candidates for part consolidation. Then the product disassembly complexity (PDC) can be used to measure disassembly complexity of a product before and after part consolidation. A case study is performed to demonstrate the usefulness of the proposed design method. The proposed method contributes to guiding how to consolidate parts for enhancing product recovery.


2019 ◽  
Vol 26 (3) ◽  
pp. 531-537
Author(s):  
Brant Edward Stoner ◽  
Griffin T. Jones ◽  
Sanjay Joshi ◽  
Rich Martukanitz

Purpose The continued improvement of additive manufacturing (AM) processing has led to increased part complexity and scale. Processes such as electron beam directed energy deposition (DED) are able to produce metal AM parts several meters in scale. These structures pose a challenge for current inspection techniques because of their large size and thickness. Typically, X-ray computed tomography is used to inspect AM components, but low source energies and small inspection volumes restrict the size of components that can be inspected. This paper aims to develop digital radiography (DR) as a method for inspecting multi-meter-sized AM components and a tool that optimizes the DR inspection process. Design/methodology/approach This tool, SMART DR, provides optimal orientations and the probability of detection for flaw sizes of interest. This information enables design changes to be made prior to manufacturing that improve the inspectabitity of the component and areas of interest. Findings Validation of SMART DR was performed using a 40-mm-thick stainless-steel blade produced by laser-based DED. An optimal orientation was automatically determined to allow radiographic inspection of a thickness of 40 mm with a 70% probability of detecting 0.5 mm diameter flaws. Radiography of the blade using the optimal orientation defined by SMART DR resulted in 0.5-mm diameter pores being detected and indicated good agreement between SMART DR’s predictions and the physical results. Originality/value This paper addresses the need for non-destructive inspection techniques specifically developed for AM components.


Author(s):  
John K. Ostrander ◽  
Lauren Ryan ◽  
Snehal Dhengre ◽  
Christopher McComb ◽  
Timothy W. Simpson ◽  
...  

Abstract Virtual Reality (VR) has been shown to be an effective assistive tool in the engineering design process, aiding designers in ergonomics studies, data visualization, and manufacturing simulation. Yet there is little research exploring the advantages of VR to assist in the design for the additive manufacturing (DfAM) process. VR may present advantages over traditional computer-aided design (CAD) tools, and these advantages may be more evident as designs become more complex. The following study investigates two types of environments: 1) Immersive Virtual Reality (VR) and 2) Non-Immersive Virtual Reality (CAD) and the advantages that each environment gives to designers to assess parts for additive manufacturing. The two environments are compared to assess potential differences in DfAM decision-making. Participants familiar with DfAM are tasked with evaluating five designs of varying complexity using the Design for Additive Manufacturing Worksheet. Participant scores, evaluation times, and self-reported metrics are recorded and analyzed. Our findings indicate that as part complexity increases, DfAM scores and evaluation times increasingly differ between VR and CAD groups. We found that the VR group evaluates more complex parts at a faster rate, but with a lower accuracy when compared to the CAD group. In evaluating self-reported metrics, both groups were relatively similar; however, the CAD group reported improved confidence in identifying stress concentrations in DfAM parts. Our findings in this research identify VR as a design evaluation tool that enhances evaluation speed which speaks to its efficiency and usability; however, VR in its current form may not present the resolution necessary to identify smaller details when compared to CAD, the more accurate evaluation tool.


2019 ◽  
Vol 109 (01-02) ◽  
pp. 88-93
Author(s):  
H. Schwenke ◽  
S. Witt ◽  
H. Rentzsch

Die mobile Bearbeitung nutzt autonome Maschineneinheiten, die sich direkt zum Werkstück transportieren lassen und eine effiziente Herstellung und Reparatur von Großbauteilen erlauben. Es sind sowohl entsprechend leistungsfähige Maschinen als auch Assistenzsysteme notwendig, um der dabei steigenden Teilekomplexität und Qualitätsanforderungen gerecht zu werden. Im Projekt „MobilePerform“ wurde dieser Bedarf adressiert und ein ganzheitliches Konzept zur mobilen Bearbeitung entwickelt.   Mobile machining solutions use autonomous machining units that can be transported to different part locations, making possible easy manufacturing and repair of large industrial equipment. To cope with increasing part complexity and quality demands and ensure reliable machining processes, capable machines as well as assistance systems are needed. The project MobilePerform addressed those demands and created a holistic concept for mobile machining.


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