Experimental Evaluation of Tension and Shear Responses of Material Discontinuities in Origami-Based Sheet Metal Bending

2021 ◽  
pp. 1-29
Author(s):  
Muhammad Ali Ablat ◽  
Ala'aldin Alafaghani ◽  
Jian-Qiao Sun ◽  
Ala Qattawi
Keyword(s):  
Sheet Metal ◽  
Simple Procedure ◽  
Three Dimensional ◽  
Effective Cross Section ◽  
Cost Effective ◽  
Shear Load ◽  
Shear Tests ◽  
Cross Section Area ◽  
Simple Tension ◽  
The Impact

Abstract Origami-based sheet metal (OSM) bending uses the origami concept to form a three-dimensional (3D) structures from a two-dimensional (2D) sheet by a series of bending operation. The OSM bending relies on a material discontinuity (MD) to perform the bending operation where the MDs are subjected to tension and shear load. Even though the OSM bending is a process that is simple, cost-effective, and easy to integrate into mass production, the understanding of the OSM bending mechanics is limiting its wide application. Particularly, the deformation behavior of MDs under tension and shear load remains unknown. Hence, this work investigates the response of MDs to these loads using the standard tension and shear tests. From the tests, critical values for two different ductile fracture criteria (DFC) are determined, and the possibility of a failure occurring in OSM bending is predicted. Results show that the load-bearing capability of the MDs is related to change in the effective cross-section area of a MD. Simple tension and shear tests can provide a simple procedure to predict failure in OSM bending. The impact of self-contact occurred under shear load influences maximum shear force and accuracy of failure prediction.

Impact response of a low-cost randomly oriented fiber foam core sandwich panel

2018 ◽  
Vol 52 (25) ◽  
pp. 3429-3444 ◽  
Author(s):  
Ezequiel Buenrostro ◽  
Daniel Whisler
Keyword(s):  
Mechanical Properties ◽  
Sandwich Panel ◽  
Low Cost ◽  
Three Dimensional ◽  
Cost Effective ◽  
Foam Core ◽  
Fiber Reinforced ◽  
Manufacturing Method ◽  
Manufacturing Techniques ◽  
The Impact

Three-dimensional fiber-reinforced foam cores may have improved mechanical properties under specific strain rates and fiber volumes. But its performance as a core in a composite sandwich structure has not been fully investigated. This study explored different manufacturing techniques for the three-dimensional fiber-reinforced foam core using existing literature as a guideline to provide a proof of concept for a low-cost and easily repeatable method comprised of readily available materials. The mechanical properties of the fiber-reinforced foam were determined using a three-point bend test and compared to unreinforced polyurethane foam. The foam was then used in a sandwich panel and subjected to dynamic loading by means of a gas gun (103 s−1). High-strain impact tests validated previously published studies by showing, qualitatively and quantitatively, an 18–20% reduction in the maximum force experienced by the fiber-reinforced core and its ability to dissipate the impact force in the foam core sandwich panel. The results show potential for this cost-effective manufacturing method to produce an improved composite foam core sandwich panel for applications where high-velocity impacts are probable. This has the potential to reduce manufacturing and operating costs while improving performance.

scholarly journals Additive Manufacturing in the Construction Industry: The Comparative Competitiveness of 3D Concrete Printing

2021 ◽  
Vol 11 (9) ◽  
pp. 3865
Author(s):  
Siavash H. Khajavi ◽  
Müge Tetik ◽  
Ashish Mohite ◽  
Antti Peltokorpi ◽  
Mingyang Li ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Construction Industry ◽  
Positive Impact ◽  
Three Dimensional ◽  
Cost Effective ◽  
Robotic Arm ◽  
Process Time ◽  
Current State ◽  
The Cost ◽  
The Impact

The construction industry is facing increasing pressure to improve productivity and decrease its environmental impact. Additive manufacturing (AM) technologies, especially three-dimensional concrete printing (3DCP) technology, have provided many benefits for construction. However, holistic comparative studies of the competitiveness of 3DCP and conventional methods, from cost and time perspectives, are lacking. Choosing between the methods is difficult for practitioners. In this study, we investigated the current state of 3DCP in the construction industry using seven distinct scenarios. Our analysis was performed to illustrate the impact of design and supply chain configurations on performance. The results prove the notable competitiveness of 3DCP. In contrast to the conventional construction method, the more complex round design had a positive impact on the cost and process time in 3DCP scenarios. Additionally, we show that on-site 3DCP using a robotic arm was more cost-effective than off-site 3DCP.

Influence of stitching on the out-of-plane behavior of composite materials – A mechanistic review

2021 ◽  
pp. 002199832110092
Author(s):  
Daniel A Drake ◽  
Rani W Sullivan ◽  
Andrew E Lovejoy ◽  
Stephen B Clay ◽  
Dawn C Jegley
Keyword(s):  
High Temperature ◽  
Composite Laminates ◽  
Polymer Matrix Composites ◽  
Three Dimensional ◽  
Cost Effective ◽  
Test Methods ◽  
Sandwich Composites ◽  
Fiber Reinforced Polymer Composites ◽  
Out Of Plane ◽  
The Impact

Fiber-reinforced polymer composites are widely used in the aerospace industry due to their high stiffness and strength-to-weight ratios. However, their applicability can be limited by their relatively low interlaminar properties when compared to metallic alternatives. Through-thickness reinforcement approaches, such as stitching, z-pinning, needling, tufting, and three-dimensional weaving, have been developed in recent decades to enhance the interlaminar properties of composites. Stitching is considered to be an efficient and cost-effective method to reinforce composites in the through-thickness direction. Additionally, stitch parameters (stitch density, linear thread density, thread material, pretension, etc.) highly influence the in-plane and out-of-plane properties. This paper summarizes results from over one hundred papers on the influence of stitch parameters on fracture energy, interlaminar strength, and impact characteristics of stitched composite laminates, sandwich composites, and high-temperature composites. Much of the research on the influence of stitch parameters has focused on thermoset polymer matrix composites (PMCs), while fewer studies have investigated the impact of stitch parameters on high temperature or sandwich composites. Modification of existing and new test methods have been developed to adequately measure the effectiveness of stitching on the out-of-plane behavior of PMC panels. Results demonstrate that out-of-plane properties of PMCs are highly dependent on stitch parameters and can be enhanced by through-thickness stitching.

Cost-effective management of benign positional vertigo using canalith repositioning

2000 ◽  
Vol 122 (3) ◽  
pp. 334-339 ◽  
Author(s):  
John C. Li ◽  
Celeste J. Li ◽  
John Epley ◽  
Lynn Weinberg
Keyword(s):  
Simple Procedure ◽  
Laboratory Data ◽  
Cost Effective ◽  
Routine Practice ◽  
Effective Management ◽  
Subjective Figure ◽  
Positional Vertigo ◽  
Inappropriate Treatment ◽  
Economic Climate ◽  
The Impact

OBJECTIVE The misdiagnosis and inappropriate treatment of benign positional vertigo have resulted in significant costs to the medical system. In the current medical-economic climate, there is an increased emphasis on cost control. Recent studies have shown that the canalith repositioning procedure (CRP) is effective; the next step is to show the impact of CRP in cost-effective management of benign positional vertigo. METHODS Forty-six of 100 patients who underwent CRP for benign positional vertigo responded to a survey regarding the financial impact of their disease. They were asked to subjectively estimate the sum of all disease-related expenses. Objective substantiation of this number was estimated by tabulating physician data, laboratory data, and failed treatment costs. RESULTS The subjective figure totaled $2684.74 per individual. Summation of the tangible objective figures yielded $2009.63 per patient, corroborating the subjective figure. CONCLUSIONS Because CRP is a relatively simple procedure that can obviate many wasted expenses in most patients, we believe that it is very cost-effective and should be incorporated into routine practice.

Cost-Effective Management of bEnign Positional Vertigo Using Canalith Repositioning

2000 ◽  
Vol 122 (3) ◽  
pp. 334-339 ◽  
Author(s):  
John C. Li ◽  
Celeste J. Li ◽  
John Epley ◽  
Lynn Weinberg
Keyword(s):  
Simple Procedure ◽  
Laboratory Data ◽  
Cost Effective ◽  
Routine Practice ◽  
Effective Management ◽  
Subjective Figure ◽  
Positional Vertigo ◽  
Inappropriate Treatment ◽  
Economic Climate ◽  
The Impact

OBJECTIVE: The misdiagnosis and inappropriate treatment of benign positional vertigo have resulted in significant costs to the medical system. In the current medical-economic climate, there is an increased emphasis on cost control. Recent studies have shown that the canalith repositioning procedure (CRP) is effective; the next step is to show the impact of CRP in cost-effective management of benign positional vertigo. METHODS: Forty-six of 100 patients who underwent CRP for benign positional vertigo responded to a survey regarding the financial impact of their disease. They were asked to subjectively estimate the sum of all disease-related expenses. Objective substantiation of this number was estimated by tabulating physician data, laboratory data, and failed treatment costs. RESULTS: The subjective figure totaled $2684.74 per individual. Summation of the tangible objective figures yielded $2009.63 per patient, corroborating the subjective figure. CONCLUSIONS: Because CRP is a relatively simple procedure that can obviate many wasted expenses in most patients, we believe that it is very cost-effective and should be incorporated into routine practice.

Regulatory and sustainability initiatives lead to improved polyaminopolyamide epichlorohydrin (PAE) wet-strength resins and paper products

TAPPI Journal ◽  
2018 ◽  
Vol 17 (09) ◽  
pp. 519-532 ◽  
Author(s):  
Mark Crisp ◽  
Richard Riehle
Keyword(s):  
Health And Safety ◽  
Cost Effective ◽  
Worker Safety ◽  
Regulatory Requirements ◽  
Wet Strength ◽  
The Past ◽  
Consumer Safety ◽  
Federal Institute ◽  
Sustainability Initiatives ◽  
The Impact

Polyaminopolyamide-epichlorohydrin (PAE) resins are the predominant commercial products used to manufacture wet-strengthened paper products for grades requiring wet-strength permanence. Since their development in the late 1950s, the first generation (G1) resins have proven to be one of the most cost-effective technologies available to provide wet strength to paper. Throughout the past three decades, regulatory directives and sustainability initiatives from various organizations have driven the development of cleaner and safer PAE resins and paper products. Early efforts in this area focused on improving worker safety and reducing the impact of PAE resins on the environment. These efforts led to the development of resins containing significantly reduced levels of 1,3-dichloro-2-propanol (1,3-DCP) and 3-monochloropropane-1,2-diol (3-MCPD), potentially carcinogenic byproducts formed during the manufacturing process of PAE resins. As the levels of these byproducts decreased, the environmental, health, and safety (EH&S) profile of PAE resins and paper products improved. Recent initiatives from major retailers are focusing on product ingredient transparency and quality, thus encouraging the development of safer product formulations while maintaining performance. PAE resin research over the past 20 years has been directed toward regulatory requirements to improve consumer safety and minimize exposure to potentially carcinogenic materials found in various paper products. One of the best known regulatory requirements is the recommendations of the German Federal Institute for Risk Assessment (BfR), which defines the levels of 1,3-DCP and 3-MCPD that can be extracted by water from various food contact grades of paper. These criteria led to the development of third generation (G3) products that contain very low levels of 1,3-DCP (typically <10 parts per million in the as-received/delivered resin). This paper outlines the PAE resin chemical contributors to adsorbable organic halogens and 3-MCPD in paper and provides recommendations for the use of each PAE resin product generation (G1, G1.5, G2, G2.5, and G3).

Exploring the Benefits of Early Contractor Involvement (ECI) and the Mechanism for Automated 5D BIM Quantification Process in Offsite Modular Construction

2016 ◽  
Author(s):  
Tochukwu Moses ◽  
David Heesom ◽  
David Oloke ◽  
Martin Crouch
Keyword(s):  
Effective Means ◽  
Cost Effective ◽  
Modular Construction ◽  
Automated Quantification ◽  
Building Information ◽  
Project Risks ◽  
Value Add ◽  
The Uk ◽  
The Impact ◽  
Level 2

The UK Construction Industry through its Government Construction Strategy has recently been mandated to implement Level 2 Building Information Modelling (BIM) on public sector projects. This move, along with other initiatives is key to driving a requirement for 25% cost reduction (establishing the most cost-effective means) on. Other key deliverables within the strategy include reduction in overall project time, early contractor involvement, improved sustainability and enhanced product quality. Collaboration and integrated project delivery is central to the level 2 implementation strategy yet the key protocols or standards relative to cost within BIM processes is not well defined. As offsite construction becomes more prolific within the UK construction sector, this construction approach coupled with BIM, particularly 5D automated quantification process, and early contractor involvement provides significant opportunities for the sector to meet government targets. Early contractor involvement is supported by both the industry and the successive Governments as a credible means to avoid and manage project risks, encourage innovation and value add, making cost and project time predictable, and improving outcomes. The contractor is seen as an expert in construction and could be counter intuitive to exclude such valuable expertise from the pre-construction phase especially with the BIM intent of äóÖbuild it twiceäó», once virtually and once physically. In particular when offsite construction is used, the contractoräó»s construction expertise should be leveraged for the virtual build in BIM-designed projects to ensure a fully streamlined process. Building in a layer of automated costing through 5D BIM will bring about a more robust method of quantification and can help to deliver the 25% reduction in overall cost of a project. Using a literature review and a case study, this paper will look into the benefits of Early Contractor Involvement (ECI) and the impact of 5D BIM on the offsite construction process.

Analyzing the Impact of X-Ray Tomography on the Reliability of Integrated Circuits

2015 ◽  
Author(s):  
Halit Dogan ◽  
Md Mahbub Alam ◽  
Navid Asadizanjani ◽  
Sina Shahbazmohamadi ◽  
Domenic Forte ◽  
...  
Keyword(s):  
Integrated Circuits ◽  
Integrated Circuit ◽  
3D Imaging ◽  
Three Dimensional ◽  
Serial Sectioning ◽  
Promising Technique ◽  
Flash Memories ◽  
X Ray ◽  
3D Information ◽  
The Impact

Abstract X-ray tomography is a promising technique that can provide micron level, internal structure, and three dimensional (3D) information of an integrated circuit (IC) component without the need for serial sectioning or decapsulation. This is especially useful for counterfeit IC detection as demonstrated by recent work. Although the components remain physically intact during tomography, the effect of radiation on the electrical functionality is not yet fully investigated. In this paper we analyze the impact of X-ray tomography on the reliability of ICs with different fabrication technologies. We perform a 3D imaging using an advanced X-ray machine on Intel flash memories, Macronix flash memories, Xilinx Spartan 3 and Spartan 6 FPGAs. Electrical functionalities are then tested in a systematic procedure after each round of tomography to estimate the impact of X-ray on Flash erase time, read margin, and program operation, and the frequencies of ring oscillators in the FPGAs. A major finding is that erase times for flash memories of older technology are significantly degraded when exposed to tomography, eventually resulting in failure. However, the flash and Xilinx FPGAs of newer technologies seem less sensitive to tomography, as only minor degradations are observed. Further, we did not identify permanent failures for any chips in the time needed to perform tomography for counterfeit detection (approximately 2 hours).

Pound Wise and Penny Foolish? Weight Loss and The Dynamics of Health Care Spending

2011 ◽  
Vol 14 (2) ◽  
Author(s):  
Thomas G Koch
Keyword(s):  
Weight Loss ◽  
Cost Savings ◽  
Cost Effective ◽  
Economic Consequences ◽  
Health Care Spending ◽  
Order Of Magnitude ◽  
Dynamic Measures ◽  
The Cost ◽  
The Impact ◽  
The Relationship

Current estimates of obesity costs ignore the impact of future weight loss and gain, and may either over or underestimate economic consequences of weight loss. In light of this, I construct static and dynamic measures of medical costs associated with body mass index (BMI), to be balanced against the cost of one-time interventions. This study finds that ignoring the implications of weight loss and gain over time overstates the medical-cost savings of such interventions by an order of magnitude. When the relationship between spending and age is allowed to vary, weight-loss attempts appear to be cost-effective starting and ending with middle age. Some interventions recently proven to decrease weight may also be cost-effective.

Motivating Compliance: Firm Response to Mandatory Disclosure Policies

2018 ◽  
Vol 32 (2) ◽  
pp. 103-119
Author(s):  
Colleen M. Boland ◽  
Chris E. Hogan ◽  
Marilyn F. Johnson
Keyword(s):  
Conflict Of Interest ◽  
Low Cost ◽  
Cost Effective ◽  
Data Availability ◽  
Policy Adoption ◽  
Future Research ◽  
Regulated Firms ◽  
Firm Response ◽  
Disclosure Rules ◽  
The Impact

SYNOPSIS Mandatory existence disclosure rules require an organization to disclose a policy's existence, but not its content. We examine policy adoption frequencies in the year immediately after the IRS required mandatory existence disclosure by nonprofits of various governance policies. We also examine adoption frequencies in the year of the subsequent change from mandatory existence disclosure to a disclose-and-explain regime that required supplemental disclosures about the content and implementation of conflict of interest policies. Our results suggest that in areas where there is unclear regulatory authority, mandatory existence disclosure is an effective and low cost regulatory device for encouraging the adoption of policies desired by regulators, provided those policies are cost-effective for regulated firms to implement. In addition, we find that disclose-and-explain regulatory regimes provide stronger incentives for policy adoption than do mandatory existence disclosure regimes and also discourage “check the box” behavior. Future research should examine the impact of mandatory existence disclosure rules in the year that the regulation is implemented. Data Availability: Data are available from sources cited in the text.

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