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The purpose of this paper is to investigate the effect of process parameters of fused deposition modelling (FDM) 3D printing process on viscoelastic responses (creep compliance and recoverable compliance) of FDM built parts using a novel experimental design technique.

As part of the process characterization, a recently developed class of three-level design methodology – definitive screening design (DSD) – was used in this study to fit a second-order polynomial regression model. Artificial neural network (ANN) was also used to determine the optimal process parameters to improve creep compliance and recoverable compliance. The relationship between layer thickness, air gap, raster angle, build orientation, road width, number of contours and creep performance of FDM fabricated part was thereafter established empirically. Scanning electron microscope (SEM) is used to examine and characterize the morphology of the structures for some samples.

This study found that the creep resistance of FDM-manufactured part is significantly influenced by layer thickness, air gap, raster angle and number of contours and it can be improved by optimizing the settings of the selected parameters. The relationship between FDM process parameters and creep properties was determined, with the best creep performance observed by using 0.127 mm of layer thickness, zero air gap, zero raster angle, build orientation of 17.188°, road width of 0.4572 mm and 10 contours. Finally, the result is verified by confirmation experiments. The results prove that a DSD is a very effective design in characterizing the influence of process parameters on creep properties of FDM-built part at the lowest cost.

The originality of this paper lies in characterizing and optimizing the effect of process parameters on creep performance of FDM manufactured part that has not been studied in all previous studies. The paper highlights, for the first time, how the application of DSD can overcome most of the limitations encountered in the conventional techniques. This study can be used as a guide to the different additive manufacturing users of various industries and the results provide a good technical database on how FDM process parameters influence the creep performance of manufactured parts.

Fused deposition modeling (FDM) has become an increasingly important process among the available additive manufacturing technologies in various industries. Although there are many advantages of FDM process, a downside of its industrial application is the attainable dimensional accuracy with tight tolerance without compromising the mechanical performance. This paper aims to study the effects of six FDM operating parameters on two conflicting responses, namely, dynamic stiffness and dimensional stability of FDM produced PC-ABS parts. This study also aims to determine the optimal process settings using graphical optimization that satisfy the dynamic mechanical properties without compromising the dimensional accuracy.

The regression models based upon IV-optimal response surface methodology are developed to study the variation of dimensional accuracy and dynamic mechanical properties with changes in process parameter settings. Statistical analysis was conducted to establish the relationships between process variables and dimensional accuracy and dynamic stiffness. Analysis of variance is used to define the level of significance of the FDM operating parameters. Scanning electron microscope and Leica MZ6 optical microscope are used to examine and characterize the morphology of the structures for some specimens.

Experimental results highlight the individual and interaction effects of processing conditions on the dynamic stiffness and part accuracy. The results showed that layer thickness (slice height), raster-to-raster air gap and number of outlines have the largest effect on the dynamic stiffness and dimensional accuracy. The results also showed an interesting phenomenon of the effect of number of contours and the influence of other process parameters. The optimal process conditions for highest mechanical performance and part accuracy are obtained.

The effect of FDM processing parameters on the properties under dynamic and cyclic loading conditions has not been studied in the previous published work. Furthermore, simultaneous optimization of dynamic mechanical properties without compromising the dimensional accuracy has also been investigated. On the basis of experimental findings, it is possible to provide practical suggestions to set the optimal FDM process parameters in relation to dynamic mechanical performance, as well as the dimensional accuracy.

Combination of advanced imaging, designing and manufacturing techniques has been rapidly developed in recent years for diagnostic and therapeutic purposes for medical devices. The purpose of this paper is to present a methodology for design and fabrication procedure of medical models using computer‐aided design (CAD) and fused deposition modeling (FDM) technique for application in the mandibular reconstructive surgery.

Case studies of patients with mandibular defects are examined using CAD model construction including data acquisition from computerized tomography scan and data processing. Furthermore, the effect of advanced manufacturing parameters settings in FDM methodology is investigated.

The models were used in assisting the surgeons in their reconstruction planning. A significant improvement regarding the success and convenience in surgery planning been reported.

This paper explores the application and viability of FDM rapid prototyping technology for fabrication of complex mandibular models used for reconstructive surgery.

This paper presents an investigation on the line balancing of an automated cylinder block production transfer line in order to reduce the total cycle time and increase machine utilization in an automotive plant. Results were verified by computer simulation, which showed increased throughput and higher machine utilization as a result of line balancing.

Three main operation lines of the transfer line were identified as critical and having the highest cycle time and were chosen for optimisation study. Strategies of re‐sequencing of existing operations and tools were used to reduce the cycle time of these critical operations and to balance the line. Results of a simulation study using Simul8 software are also presented to demonstrate the increase in machine utilisation and throughput as a result of line balancing.

Owing to line balancing, the cycle time of cylinder block line was reduced from 293.9 to 200 s, an almost 32 per cent reduction. This also resulted in increased throughput and machine utilisation. Throughput was increased by 65 per cent. Machine utilization was found to increase at all stations, with the highest increase at one station was recorded from 48 to 95 per cent due to balancing.

Introduces a new application to line balancing of automotive cylinder block production line. Demonstrates that effective strategies of re‐sequencing and changing of tools can lead to more balanced production line with increased throughput and higher machining utilisation, resulting in higher productivity.

This paper aims to investigate the changes in tensile properties of novel functionally graded materials (FGMs) and wafer structures created by direct metal deposition (DMD) additive manufacturing (AM) technology.

Laser-assisted DMD was used to create two innovative sets of metallic structures – the functionally graded and wafer-layered structures – using pairs of six different engineering alloys in different combinations. These alloys were selected due to their high popularity within a diverse range of industries and engineering applications. The laser-assisted DMD was selected as a suitable technique to create these complex structures because of its capability to deposit more than one alloy powder at a time. After creation of these structures, their tensile strength was tested in a series of tensile tests and the results were compared with those of single alloy samples.

It was observed that the mechanical properties of FGMs and wafer structure samples were clearly different from those of the single alloy samples, a fact which creates a whole pool of opportunities for development of new materials or structures with desired mechanical properties that cannot be achieved in single alloy parts.

The study demonstrates the application of the DMD process to produce unique structures and materials, which would be high in demand in engineering applications, where metallic parts are exposed to high loads and where excessive tensile stresses may adversely affect the performance of such parts.

Automated chopper gun trajectory planning (CGTP) for spray forming is highly desirable for today's automotive manufacturing. Generating chopper gun trajectories for free‐form surfaces to satisfy material distribution requirements is still highly challenging due to the complexity of the problems. In this paper, a user‐friendly software for automated CGTP has been developed. The CGTP software can take different formats of the CAD models of parts. A chopper gun trajectory is generated based on the CAD model of a part, chopper gun model, and constraints. A part is partitioned into patches to satisfy the given constraints. A trajectory integration algorithm is developed to integrate the trajectories of the patches to form a trajectory for the part. The CGTP software has been tested by Ford Motor Company and achieved satisfactory results.

Explains that fused deposition modelling is a rapid prototyping technology by which physical objects are created directly from a CAD model using layer by layer deposition of extruded material. The technology offers the potential of producing parts accurately in a wide range of materials safely and quickly. In using this technology, the designer is often confronted with a host of conflicting options including achieving desired accuracy, optimizing building time and cost and fulfilling functionality requirements. Presents a methodology for resolving these problems through the development of an intelligent rapid prototyping syste integrating distributed blackboard technologies with different knowledge based systems and feature based design technologies.

Additive manufacturing (AM) technology has a huge influence on the real world because of its ability to manufacture massively complicated geometrics. The purpose of this study is to use CiteSpace (CS) visual analysis to identify fused deposition modeling (FDM) research and development patterns to guide researchers to decide future research and provide a framework for corporations and organizations to prepare for the development in the rapid prototyping industry. Three-dimensional printing (3DP) is defined to budget minimize manufactured input and output for aviation and the medical product industrial sectors. 3DP has implemented its potential in the Coronavirus Disease of 2019 (COVID-19) reaction.

First, 396 original publications were extracted from the web of science (WOS) with the comprehensive list and did scientometrics analysis in CS software. The parameters are specified in CS including the span (from 2011 to 2019, one year slice for the co-authorship and the co-accordance analysis), visualization (show the merged networks), specific criteria for selection (top 20%), node form (author, organization, region, reference cited; cited author, journal and keywords) and pruning (pathfinder and slicing network). Finally, correlating data was studied and showed the results of the visualization study of FDM research were shown.

The framework of FDM information is beginning to take shape. About hot research topics, there are “Morphology,” “Tensile Property by making Blends,” “Use of Carbon nanotube in 3DP” and “Topology optimization.” Regarding the latest research frontiers of FDM printing, there are “Fused Filament Fabrication,” “AM,” in FDM printing. Where “Post-processing” and “environmental impact” are the research hotspots in FDM printing. These research results can provide insight into FDM printing and useful information to consider the existing studies and developments in FDM researchers’ analysis.

Despite some important obtained results through FDM-related publications’ visualization, some deficiencies remain in this research. With >99% of articles written in English, the input data for CS was all downloaded from WOS databases, resulting in a language bias of papers in other languages and neglecting other data sources. Although, there are several challenges being faced by the FDM that limit its wide variety of applications. However, the significance of the current work concerning the technical and engineering prospects is discussed herein.

First, the novelty of this work lies in describing the FDM approach in a Scientometric way. In Scientometric investigation, leading writers, organizations, keywords, hot research and emerging knowledge points were explained. Second, this research has thoroughly and comprehensively examined the useful sustainability effects, i.e. economic sustainability, energy-based sustainability, environmental sustainability, of 3DP in industrial development in qualitative and quantitative aspects by 2025 from a global viewpoint. Third, this work also described the practical significance of FDM based on 3DP since COVID-19. 3DP has stepped up as a vital technology to support improved healthcare and other general response to emergency situations.

The major goals of this study are to investigate the existing state of affairs concerning daylighting, glare and thermal comfort in the building, which will be the focus of the investigation, particularly in connection to the building’s energy efficiency considering student task performances. EnergyPlus, which is a software for building energy modeling, is applied to evaluate the energy consumption of buildings under a variety of circumstances related to their design. With the use of a variety of simulations, the goal of this study is to provide building design options that are both the most efficient and the most cost-effective for the case study building.

There are three distinct categories that can be applied throughout the entire process. The first thing that has to be done is to choose a building to use as a case study and then conduct an analysis of the current situation to address the existing problem. In the following step, several passive design measures are implemented and simulated in order to solve the challenges that are currently being faced. A detailed cost analysis is carried out as the final step in the process of determining whether or not it is feasible.

According to the findings: A cantilevered 3’ drop wall as a shading system, an east-facing model, and a window with a height of 4.5 is the ideal configuration. The annual energy can be saved by 22.5%. The payback period is 11 years. Benefit/Cost >1 makes it a feasible and economical solution.

The work is completely original. No one have done this before.

Strategic Management and Organization Theory and Design.

Advanced undergraduate and MBA students taking courses in Strategic Management and Organization Theory and Design.

By the end of 2011, five years short of its centennial anniversary, UMW Holdings was one of the biggest corporations in Malaysia, registering revenues of RM13.5 billion (US$4.5 billion), and net profit after tax of RMI billion (US$0.33 billion). By that time, it had 110 subsidiaries, operating in four core businesses of automotive assembly and distribution of Toyota lines of products, automotive components and lubricants original equipment manufacturing (OEM) and replacement equipment manufacturing (REM), heavy equipment, and oil and gas drilling service. In September 2011, the company had targeted its Toyota automotive business to contribute to 50 percent of its revenues, while the other 50 percent would come from its other three businesses, by the year 2015. However, as of the first quarter of 2012, Datuk Syed Hisham Syed Wazir, the Group CEO and his management team realized that, at 72 percent, the automotive business was still the main contributor to the Group's revenues. As the company's Toyota assembly operation was limited exclusively to the Malaysian market, plus in the face of greater competition within the automotive industries, the company needed to set strategies to achieve its 50:50 plan. The case stimulates discussion on strategy formulation of a mature corporation, involved in diversified business portfolio.

Understanding the process of industry analysis, as well as the formulation and implementation of business-level and corporate strategies, enables case analysts to extend the concepts to many business situations.

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