Minimizing the cycle time in multiple-dwell cams

2012 ◽  
Vol 227 (4) ◽  
pp. 794-805 ◽  
Author(s):  
Forrest W Flocker ◽  
Ramiro H Bravo
Keyword(s):  
Cycle Time ◽  
Manufacturing Sector ◽  
Low Cost ◽  
Capital Costs ◽  
Manufacturing Operations ◽  
Manufacturing Efficiency ◽  
Minimal Cycle ◽  
Cam Follower ◽  
Data Points ◽  
High Production

Presented in this article are closed-form kinematic equations that give the minimum cycle time for multiple-dwell cam-follower systems subject to acceleration and jerk constraints set by the user. Cam-driven machines are used extensively in manufacturing because of their low cost, great precision and high production rates when compared with alternatives. Since they are frequently used in mass production operations, there is a need for minimizing their cycle time to increase manufacturing throughput and reduce capital costs for machines and facilities. Their widespread use means that there is the potential for significant improvement in overall manufacturing efficiency. The incorporation of acceleration and jerk limits in the kinematic formulation ensures minimal cycle time without compromising the operational limits of the manufacturing machines. The equations are given in a form suitable for spreadsheet or equation-solver programs, making it easy for the cam designer to generate an arbitrary number of data points for cam manufacturing. Multiple-dwell cams are particularly well suited for manufacturing operations; therefore, the intended audience of this paper is cam designers in the manufacturing sector.

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

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.

scholarly journals A Person-to-Person and Person-to-Place COVID-19 Contact Tracing System Based on OGC IndoorGML

2020 ◽  
Vol 10 (1) ◽  
pp. 2 ◽  
Author(s):  
Soroush Ojagh ◽  
Sara Saeedi ◽  
Steve H. L. Liang
Keyword(s):  
Data Model ◽  
Low Cost ◽  
Large Body ◽  
Contact Tracing ◽  
Trajectory Data ◽  
Sequential Order ◽  
Human Contact ◽  
Wide Availability ◽  
Data Points ◽  
The Impact

With the wide availability of low-cost proximity sensors, a large body of research focuses on digital person-to-person contact tracing applications that use proximity sensors. In most contact tracing applications, the impact of SARS-CoV-2 spread through touching contaminated surfaces in enclosed places is overlooked. This study is focused on tracing human contact within indoor places using the open OGC IndoorGML standard. This paper proposes a graph-based data model that considers the semantics of indoor locations, time, and users’ contexts in a hierarchical structure. The functionality of the proposed data model is evaluated for a COVID-19 contact tracing application with scalable system architecture. Indoor trajectory preprocessing is enabled by spatial topology to detect and remove semantically invalid real-world trajectory points. Results show that 91.18% percent of semantically invalid indoor trajectory data points are filtered out. Moreover, indoor trajectory data analysis is innovatively empowered by semantic user contexts (e.g., disinfecting activities) extracted from user profiles. In an enhanced contact tracing scenario, considering the disinfecting activities and sequential order of visiting common places outperformed contact tracing results by filtering out unnecessary potential contacts by 44.98 percent. However, the average execution time of person-to-place contact tracing is increased by 58.3%.

scholarly journals Design and implementation of a three dimensions (3D) printer for modeling and pre-manufacturing applications

2019 ◽  
Vol 9 (6) ◽  
pp. 4749
Author(s):  
Ghazi Qaryouti ◽  
Abdel Rahman Salbad ◽  
Sohaib A. Tamimi ◽  
Anwar Almofleh ◽  
Wael A. Salah ◽  
...  
Keyword(s):  
3D Printing ◽  
Manufacturing Sector ◽  
Low Cost ◽  
Three Dimensional ◽  
Three Dimensions ◽  
3D Printer ◽  
Overall Design ◽  
Design And Implementation ◽  
Manufacturing Applications ◽  
Functional Components

The three-dimensional (3D) printing technologies represent a revolution in the manufacturing sector due to their unique characteristics. These printers arecapable to increase the productivitywithlower complexity in addition tothe reduction inmaterial waste as well the overall design cost prior large scalemanufacturing.However, the applications of 3D printing technologies for the manufacture of functional components or devices remain an almost unexplored field due to their high complexity. In this paper the development of 3D printing technologies for the manufacture of functional parts and devices for different applications is presented. The use of 3D printing technologies in these applicationsis widelyused in modelingdevices usually involves expensive materials such as ceramics or compounds. The recent advances in the implementation of 3D printing with the use of environmental friendly materialsin addition to the advantages ofhighperformance and flexibility. The design and implementation of relatively low-cost and efficient 3D printer is presented. The developed prototype was successfully operated with satisfactory operated as shown from the printed samples shown.

Macroseismic survey of the 6 February 2016 KwaZulu-Natal, South Africa earthquake

2021 ◽  
Author(s):  
V. Mapuranga ◽  
A. Kijko ◽  
I. Saunders ◽  
A. Singh ◽  
M. Singh ◽  
...  
Keyword(s):  
Structural Damage ◽  
Low Cost ◽  
The United States ◽  
United States Geological Survey ◽  
Intensity Data ◽  
Eastern Cape ◽  
Kwazulu Natal ◽  
Data Points ◽  
Macroseismic Survey ◽  
Intensity Data Points

Abstract On the 6th of February 2016 at 11:00 hours local time (0900 UTC), KwaZulu-Natal was struck by an earthquake of local magnitude ML=3.8. The epicentre of the earthquake was located offshore in the Durban Basin. The earthquake shaking was widely felt within the province as well as in East London in the Eastern Cape province and was reported by various national media outlets. Minor structural damage was reported. A macroseismic survey using questionnaires was conducted by the Council for Geoscience (CGS) in collaboration with the University of KwaZulu-Natal (UKZN) which yielded 41 intensity data points. Additional intensity data points were obtained from the United States Geological Survey (USGS) Did You Feel It? programme. An attempt was made to define a local intensity attenuation model. Generally, the earthquake was more strongly felt in low-cost housing neighbourhoods than in more affluent suburbs.

scholarly journals Surface Engineering of Ceramic Nanomaterials for Separation of Oil/Water Mixtures

2020 ◽  
Vol 8 ◽  
Author(s):  
Usama Zulfiqar ◽  
Andrew G. Thomas ◽  
Allan Matthews ◽  
David J. Lewis
Keyword(s):  
Surface Engineering ◽  
Oil Spills ◽  
Chemical Interaction ◽  
Low Cost ◽  
Water Mixture ◽  
Water Separation ◽  
Manufacturing Operations ◽  
Industrial Oil ◽  
Oil Water Separation ◽  
Oil Water

Oil/water mixtures are a potentially major source of environmental pollution if efficient separation technology is not employed during processing. A large volume of oil/water mixtures is produced via many manufacturing operations in food, petrochemical, mining, and metal industries and can be exposed to water sources on a regular basis. To date, several techniques are used in practice to deal with industrial oil/water mixtures and oil spills such as in situ burning of oil, bioremediation, and solidifiers, which change the physical shape of oil as a result of chemical interaction. Physical separation of oil/water mixtures is in industrial practice; however, the existing technologies to do so often require either dissipation of large amounts of energy (such as in cyclones and hydrocyclones) or large residence times or inventories of fluids (such as in decanters). Recently, materials with selective wettability have gained attention for application in separation of oil/water mixtures and surfactant stabilized emulsions. For example, a superhydrophobic material is selectively wettable toward oil while having a poor affinity for the aqueous phase; therefore, a superhydrophobic porous material can easily adsorb the oil while completely rejecting the water from an oil/water mixture, thus physically separating the two components. The ease of separation, low cost, and low-energy requirements are some of the other advantages offered by these materials over existing practices of oil/water separation. The present review aims to focus on the surface engineering aspects to achieve selectively wettability in materials and its their relationship with the separation of oil/water mixtures with particular focus on emulsions, on factors contributing to their stability, and on how wettability can be helpful in their separation. Finally, the challenges in application of superwettable materials will be highlighted, and potential solutions to improve the application of these materials will be put forward.

scholarly journals Whole Conversion of Soybean Molasses into Isomaltulose and Ethanol by Combining Enzymatic Hydrolysis and Successive Selective Fermentations

Biomolecules ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 353
Author(s):  
Zhi-Peng Wang ◽  
Lin-Lin Zhang ◽  
Song Liu ◽  
Xiao-Yan Liu ◽  
Xin-Jun Yu
Keyword(s):  
Low Cost ◽  
Rhizomucor Miehei ◽  
Pichia Stipitis ◽  
Raffinose Family Oligosaccharides ◽  
Alternative Substrate ◽  
Soy Molasses ◽  
High Production ◽  
Novel Strategy ◽  
High Production Cost ◽  
High Sucrose

Isomaltulose is mainly produced from sucrose by microbial fermentation, when the utilization of sucrose contributes a high production cost. To achieve a low-cost isomaltulose production, soy molasses was introduced as an alternative substrate. Firstly, α-galactosidase gene from Rhizomucor miehei was expressed in Yarrowia lipolytica, which then showed a galactosidase activity of 121.6 U/mL. Under the effects of the recombinant α-galactosidase, most of the raffinose-family oligosaccharides in soy molasses were hydrolyzed into sucrose. Then the soy molasses hydrolysate with high sucrose content (22.04%, w/w) was supplemented into the medium, with an isomaltulose production of 209.4 g/L, and the yield of 0.95 g/g. Finally, by virtue of the bioremoval process using Pichia stipitis, sugar byproducts in broth were transformed into ethanol at the end of fermentation, thus resulting in high isomaltulose purity (97.8%). The bioprocess employed in this study provides a novel strategy for low-cost and efficient isomaltulose production from soybean molasses.

scholarly journals Design of a Compact Planar Rectenna for Wireless Power Transfer in the ISM Band

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Fang Zhang ◽  
Xin Liu ◽  
Fan-Yi Meng ◽  
Qun Wu ◽  
Jong-Chul Lee ◽  
...  
Keyword(s):  
Cycle Time ◽  
Design Methodology ◽  
Low Cost ◽  
Wireless Power ◽  
High Conversion Efficiency ◽  
Operation Mechanism ◽  
Ism Band ◽  
Design Cycle ◽  
Rectenna Design ◽  
Compact Planar

This paper presents a compact planar rectenna with high conversion efficiency in the ISM band. The proposed rectenna is developed by the decomposing of a planar rectenna topology into two functional parts and then recombining the two parts into a new topology to make the rectenna size reduction. The operation mechanism of the antenna and rectifying circuit in the proposed novel topology is explained and the design methodology is presented in detail. The proposed topology not only reduces the rectenna design cycle time but also leads to easy realization at the required frequency ranges with a very low cost. For validation, a 2.45 GHz rectenna system is designed and measured to show their microwave performances.

scholarly journals Design and Fabrication of Wafer-Level Microlens Array with Moth-Eye Antireflective Nanostructures

Nanomaterials ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 747 ◽  
Author(s):  
Shuping Xie ◽  
Xinjun Wan ◽  
Bo Yang ◽  
Wei Zhang ◽  
Xiaoxiao Wei ◽  
...  
Keyword(s):  
Nanoimprint Lithography ◽  
Production Efficiency ◽  
Low Cost ◽  
Microlens Array ◽  
Wafer Level ◽  
Lens Array ◽  
Wafer Level Packaging ◽  
High Production ◽  
Aspherical Lenses ◽  
Profile Accuracy

Wafer-level packaging (WLP) based camera module production has attracted widespread industrial interest because it offers high production efficiency and compact modules. However, suppressing the surface Fresnel reflection losses is challenging for wafer-level microlens arrays. Traditional dielectric antireflection (AR) coatings can cause wafer warpage and coating fractures during wafer lens coating and reflow. In this paper, we present the fabrication of a multiscale functional structure-based wafer-level lens array incorporating moth-eye nanostructures for AR effects, hundred-micrometer-level aspherical lenses for camera imaging, and a wafer-level substrate for wafer assembly. The proposed fabrication process includes manufacturing a wafer lens array metal mold using ultraprecise machining, chemically generating a nanopore array layer, and replicating the multiscale wafer lens array using ultraviolet nanoimprint lithography. A 50-mm-diameter wafer lens array is fabricated containing 437 accurate aspherical microlenses with diameters of 1.0 mm; each lens surface possesses nanostructures with an average period of ~120 nm. The microlens quality is sufficient for imaging in terms of profile accuracy and roughness. Compared to lenses without AR nanostructures, the transmittance of the fabricated multiscale lens is increased by ~3% under wavelengths of 400–750 nm. This research provides a foundation for the high-throughput and low-cost industrial application of wafer-level arrays with AR nanostructures.

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