74 research outputs found
Review of test methods used for the measurement of hermeticity in packages containing small cavities
Parametrical modeling and design optimization of blood plasma separation device with microchannel mechanism
This paper presents an analysis of biofluid behavior in a T-shaped microchannel device and a design optimization for improved biofluid performance in terms of particle liquid separation. The biofluid is modeled with single phase shear rate non-Newtonian flow with blood property. The separation of red blood cell from plasma is evident based on biofluid distribution in the microchannels against various relevant effects and findings, including Zweifach-Fung bifurcation law, Fahraeus effect, Fahraeus-Lindqvist effect and cell free phenomenon. The modeling with the initial device shows that this T-microchannel device can separate red blood cell from plasma but the separation efficiency among different bifurcations varies largely. In accordance with the imbalanced performance, a design optimization is conducted. This includes implementing a series of simulations to investigate the effect of the lengths of the main and branch channels to biofluid behavior and searching an improved design with optimal separation performance. It is found that changing relative lengths of branch channels is effective to both uniformity of flow rate ratio among bifurcations and reduction of difference of the flow velocities between the branch channels, whereas extending the length of the main channel from bifurcation region is only effective for uniformity of flow rate ratio
Wireless Power Transfer Techniques for Implantable Medical Devices:A Review
Wireless power transfer (WPT) systems have become increasingly suitable solutions for the electrical powering of advanced multifunctional micro-electronic devices such as those found in current biomedical implants. The design and implementation of high power transfer efficiency WPT systems are, however, challenging. The size of the WPT system, the separation distance between the outside environment and location of the implanted medical device inside the body, the operating frequency and tissue safety due to power dissipation are key parameters to consider in the design of WPT systems. This article provides a systematic review of the wide range of WPT systems that have been investigated over the last two decades to improve overall system performance. The various strategies implemented to transfer wireless power in implantable medical devices (IMDs) were reviewed, which includes capacitive coupling, inductive coupling, magnetic resonance coupling and, more recently, acoustic and optical powering methods. The strengths and limitations of all these techniques are benchmarked against each other and particular emphasis is placed on comparing the implanted receiver size, the WPT distance, power transfer efficiency and tissue safety presented by the resulting systems. Necessary improvements and trends of each WPT techniques are also indicated per specific IMD
A scientific information extraction dataset for nature inspired engineering
Nature has inspired various ground-breaking technological developments in
applications ranging from robotics to aerospace engineering and the
manufacturing of medical devices. However, accessing the information captured
in scientific biology texts is a time-consuming and hard task that requires
domain-specific knowledge. Improving access for outsiders can help
interdisciplinary research like Nature Inspired Engineering. This paper
describes a dataset of 1,500 manually-annotated sentences that express
domain-independent relations between central concepts in a scientific biology
text, such as trade-offs and correlations. The arguments of these relations can
be Multi Word Expressions and have been annotated with modifying phrases to
form non-projective graphs. The dataset allows for training and evaluating
Relation Extraction algorithms that aim for coarse-grained typing of scientific
biological documents, enabling a high-level filter for engineers.Comment: Published in Proceedings of the 12th Conference on Language Resources
and Evaluation (LREC 2020). Updated dataset statistics, results unchange
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