Production of Synthetic Models for Neuro-Oncology Training by Additive Manufacturing

Neurosurgery is one of the medical specialties in which the practical training of students is more limiting since it requires a high degree of preparation for the interventions to be satisfactory. That is why the manufacture of synthetic models through additive manufacturing (AM) arises to develop the skills that the neurosurgeon requires. The present work is aimed at validating the use of AM for the neurosurgery training. To this regard, a meningioma case study was considered, and suitable materials and more appropriate AM technology were identified for a low-cost production of synthetic models of both skulls and brains with tumors. The skull was manufactured by material extrusion AM with two materials, a commercial composite filament composed of polylactic acid (PLA) with calcium carbonate (used in the area to be treated during the cutting process, due to its mechanical properties more comparable to those of the native bone, with 30% infill density) and standard PLA without additives (used in the rest of the model, with 20% infill density). On the other hand, different casting silicones in different proportions were tested under compression molding to find the best combination to mimic the brain and tumor. Ten synthetic models of a real-case meningioma were manufactured and used as training material by students in the neurosurgery sector, who rated the proposed training approach very highly, considering the employment of printed models as a key resource for improving their surgical skills.

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Learning from Past Policy: Assessing United States Foreign Policy over Indonesia in Resolving the 1999 East Timor Crisis

Global Jurnal Politik Internasional ◽

10.7454/global.v23i1.579 ◽

2021 ◽

Vol 23 (1) ◽

pp. 1

Author(s):

Sigit S. Nugroho

Keyword(s):

United States ◽

Foreign Policy ◽

Low Cost ◽

The United States ◽

East Timor ◽

United States Foreign Policy ◽

Case Study Analysis ◽

High Degree ◽

The U.S

Assessing the output of past foreign policy is instrumental for any country to learn policy-relevant insights, to appreciate its experience, and to improve its future conduct. To glean such insights, this article borrows Baldwin’s framework in assessing the success and failure in foreign policy. Using a case study analysis, it assesses the United States’ (U.S.) influence attempt towards Indonesia to resolve the 1999 East Timor humanitarian crisis. President Clinton’s decision to undergo an influence attempt primarily aimed to change Indonesia’s policy while gaining support from U.S. allies in the process. The article finds that Clinton’s decision was a highly successful attempt. This finding is based on several factors: (1) the attempt effectively attained the intended primary and secondary goals at a considerably high degree; (2) it was conducted at a considerably low cost for the U.S.; (3) it inflicted a high cost towards Indonesia; (4) the increase in Clinton’s stake strengthened the U.S. resolve to pursue the influence attempt; and (5) Clinton had successfully overcome the difficult undertaking as Indonesia possessed higher stake over East Timor. These findings provide some lessons for both U.S. and Indonesian foreign policymakers to chart future relations for the two nations.

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Application of Topology Optimization and Design for Additive Manufacturing Guidelines on an Automotive Component

Volume 2A: 42nd Design Automation Conference ◽

10.1115/detc2016-59719 ◽

2016 ◽

Cited By ~ 5

Author(s):

Sai Nithin Reddy K. ◽

Vincent Maranan ◽

Timothy W. Simpson ◽

Todd Palmer ◽

Corey J. Dickman

Keyword(s):

Topology Optimization ◽

Additive Manufacturing ◽

Low Cost ◽

Engineering Practice ◽

Optimized Design ◽

Design For Additive Manufacturing ◽

Manufacturing Costs ◽

Cost Structures ◽

And Performance

Topology optimization is a well-established engineering practice to optimize the design and layout of parts to create lightweight and low-cost structures, which have historically been difficult, or impossible, to make. Additive Manufacturing (AM) provides the freedom to fabricate the complex and organic shapes that topology optimization often generates. In this paper we use topology optimization to create lightweight designs while conforming to additive manufacturing constraints related to overhanging features and unsupported surfaces when using metallic materials. More specifically, we use design for additive manufacturing (DfAM) rules along with topology optimization to study the tradeoffs between the weight of the part, support requirements, manufacturing costs, and performance. The case study entails redesigning an upright on the SAE Formula student racecar to reduce support structures and manufacturing and material cost when using Direct Metal Laser Sintering (DMLS). Manufacturing the optimized design without applying DfAM rules required support material up to 202.4% of the volume of the model. Using DfAM, the upright is redesigned and manufactured with supports requiring less than 15% of the volume of the model. The results demonstrate the challenges in achieving a balance between weight reduction, manufacturing costs, and factor of safety of the design.

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Low Temperature Fault Isolation Using Soft Defect Localization

ISTFA 2012: Conference Proceedings from the 38th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2012p0596 ◽

2012 ◽

Author(s):

Kristopher D. Staller

Keyword(s):

Low Temperatures ◽

Laser Scanning ◽

Low Cost ◽

Fault Isolation ◽

Laser Scanning Microscopy ◽

Cold Temperature ◽

Multiple Point ◽

Defect Localization ◽

Low Levels

Abstract Cold temperature failures are often difficult to resolve, especially those at extreme low levels (< -40°C). Momentary application of chill spray can confirm the failure mode, but is impractical during photoemission microscopy (PEM), laser scanning microscopy (LSM), and multiple point microprobing. This paper will examine relatively low-cost cold temperature systems that can hold samples at steady state extreme low temperatures and describe a case study where a cold temperature stage was combined with LSM soft defect localization (SDL) to rapidly identify the cause of a complex cold temperature failure mechanism.

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The Entering Marketing Strategy of the Low-cost Carrier into Korea-China Route: The Case Study of Spring Airlines, The Largest Chinese LCC

Journal of Distribution and Logistics ◽

10.22321/jdl2015020201 ◽

2015 ◽

Vol 2 (2) ◽

pp. 5-20

Author(s):

Ik Hwan Moon ◽

Se Jin An ◽

Yong Jae Yoo

Keyword(s):

Marketing Strategy ◽

Low Cost ◽

Low Cost Carrier

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Novel composite filament usable in low-cost 3D printers for fabrication of complex ceramic shapes

Applied Materials Today ◽

10.1016/j.apmt.2021.100949 ◽

2021 ◽

Vol 22 ◽

pp. 100949

Author(s):

Peter Veteška ◽

Zora Hajdúchová ◽

Jozef Feranc ◽

Katarína Tomanová ◽

Ján Milde ◽

...

Keyword(s):

Low Cost ◽

3D Printers ◽

Composite Filament

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A Regenerative Business Model with Flexible, Modular and Scalable Processes in A Post-Covid Era: The Case of The Spinning Mesh Disc Reactor (SMDR)

Sustainability ◽

10.3390/su13126944 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6944

Author(s):

Emma Anna Carolina Emanuelsson ◽

Aurelie Charles ◽

Parimala Shivaprasad

Keyword(s):

Business Model ◽

Low Cost ◽

Sustainable Manufacturing ◽

Sustainable Business ◽

Capital Costs ◽

Implementing Change ◽

Chemical Manufacturing ◽

Manufacturing Techniques ◽

Flexible Operation

With stringent environmental regulations and a new drive for sustainable manufacturing, there is an unprecedented opportunity to incorporate novel manufacturing techniques. Recent political and pandemic events have shown the vulnerability to supply chains, highlighting the need for localised manufacturing capabilities to better respond flexibly to national demand. In this paper, we have used the spinning mesh disc reactor (SMDR) as a case study to demonstrate the path forward for manufacturing in the post-Covid world. The SMDR uses centrifugal force to allow the spread of thin film across the spinning disc which has a cloth with immobilised catalyst. The modularity of the design combined with the flexibility to perform a range of chemical reactions in a single equipment is an opportunity towards sustainable manufacturing. A global approach to market research allowed us to identify sectors within the chemical industry interested in novel reactor designs. The drivers for implementing change were identified as low capital cost, flexible operation and consistent product quality. Barriers include cost of change (regulatory and capital costs), limited technical awareness, safety concerns and lack of motivation towards change. Finally, applying the key features of a Sustainable Business Model (SBM) to SMDR, we show the strengths and opportunities for SMDR to align with an SBM allowing for a low-cost, sustainable and regenerative system of chemical manufacturing.

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MODEL-BASED DESIGN OF AM COMPONENTS TO ENABLE DECENTRALIZED DIGITAL MANUFACTURING SYSTEMS

Proceedings of the Design Society ◽

10.1017/pds.2021.474 ◽

2021 ◽

Vol 1 ◽

pp. 2127-2136

Author(s):

Olivia Borgue ◽

John Stavridis ◽

Tomas Vannucci ◽

Panagiotis Stavropoulos ◽

Harry Bikas ◽

...

Keyword(s):

Additive Manufacturing ◽

Manufacturing Systems ◽

Production Systems ◽

Data Generation ◽

Production Networks ◽

Model Based ◽

Manufacturing Technologies ◽

Am Processes ◽

Final Consumer

AbstractAdditive manufacturing (AM) is a versatile technology that could add flexibility in manufacturing processes, whether implemented alone or along other technologies. This technology enables on-demand production and decentralized production networks, as production facilities can be located around the world to manufacture products closer to the final consumer (decentralized manufacturing). However, the wide adoption of additive manufacturing technologies is hindered by the lack of experience on its implementation, the lack of repeatability among different manufacturers and a lack of integrated production systems. The later, hinders the traceability and quality assurance of printed components and limits the understanding and data generation of the AM processes and parameters. In this article, a design strategy is proposed to integrate the different phases of the development process into a model-based design platform for decentralized manufacturing. This platform is aimed at facilitating data traceability and product repeatability among different AM machines. The strategy is illustrated with a case study where a car steering knuckle is manufactured in three different facilities in Sweden and Italy.

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Highly Compact Through-Wire Microstrip to Empty Substrate Integrated Coaxial Line Transition

Applied Sciences ◽

10.3390/app11156885 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6885

Author(s):

Marcos D. Fernandez ◽

José A. Ballesteros ◽

Angel Belenguer

Keyword(s):

Printed Circuit Board ◽

Low Cost ◽

Coaxial Line ◽

Circuit Board ◽

Central Layer ◽

Printed Circuit ◽

Integrated Technology ◽

Low Profile ◽

The Many ◽

High Degree

Empty substrate integrated coaxial line (ESICL) technology preserves the many advantages of the substrate integrated technology waveguides, such as low cost, low profile, or integration in a printed circuit board (PCB); in addition, ESICL is non-dispersive and has low radiation. To date, only two transitions have been proposed in the literature that connect the ESICL to classical planar lines such as grounded coplanar and microstrip. In both transitions, the feeding planar lines and the ESICL are built in the same substrate layer and they are based on transformed structures in the planar line, which must be in the central layer of the ESICL. These transitions also combine a lot of metallized and non-metallized parts, which increases the complexity of the manufacturing process. In this work, a new through-wire microstrip-to-ESICL transition is proposed. The feeding lines and the ESICL are implemented in different layers, so that the height of the ESICL can be independently chosen. In addition, it is a highly compact transition that does not require a transformer and can be freely rotated in its plane. This simplicity provides a high degree of versatility in the design phase, where there are only four variables that control the performance of the transition.

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