This paper presents a novel factor graph-based approach to solve the discrete-time finite-horizon Linear Quadratic Regulator problem subject to auxiliary linear equality constraints within and across time steps. We re...
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A portable device was designed and constructed for studying the properties of biomaterials in physiologically relevant fluids under controllable flow conditions that closely simulate fluid flow inside the *** device c...
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A portable device was designed and constructed for studying the properties of biomaterials in physiologically relevant fluids under controllable flow conditions that closely simulate fluid flow inside the *** device can fit entirely inside a cell incubator;and,thus,it can be used directly under standard cell culture *** impedance-driven pump was built in the sterile flow loop to control the flow rates of fluids,which made the device small and portable for easy deployment in the *** demonstrate the device functions,magnesium(Mg)as a representative biodegradable material was tested in the flow device for immersion degradation under flow versus static conditions,while the flow module was placed inside a standard cell *** flow rate was controlled at 0.1760.06 ml/s for this study;and,the flow rate is adjustable through the controller module outside of incubators for simulating the flow rates in the ranges of blood flow in human artery(0.050.43 ml/s)and vein(0.020.08 ml/s).Degradation of Mg under flow versus static conditions was characterized by measuring the changes of sample mass and thickness,and Mg2t ion concentrations in the immersion *** chemistry and morphology of Mg after immersion under flow versus static conditions were *** portable impedance-driven flow device is easy to fit inside an incubator and much smaller than a peristaltic pump,providing a valuable solution for studying biomaterials and implants(*** or ureteral stents)in body fluids under flow versus static conditions with or without cells.
To bridge the gap between the biological sciences (typically female-dominated) and engineering (typically male-dominated), biomedical engineering (BME) activities could potentially be used as a vehicle to alter female...
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ISBN:
(数字)9781728119908
ISBN:
(纸本)9781728119915
To bridge the gap between the biological sciences (typically female-dominated) and engineering (typically male-dominated), biomedical engineering (BME) activities could potentially be used as a vehicle to alter female students' perception of engineering as a whole. Female's pursuit of STEM (Science, Technology, engineering and Math) degrees is typically confined to the biological sciences and females earn a high proportion of degrees in nursing, psychology and the social sciences, yet male presence persists in physical sciences and engineering. Female's participation in engineering remains much lower than men at all degree levels. Here, research questions included do female high school students: 1) perceive engineering as relevant? 2) have an interest & aptitude towards exploring engineering in college and as a career? 3) have anxiety in terms of engineering? 4) have engineering "role-confidence"? Participants, a randomly selected pool of 28 high school students (almost exclusively female from schools throughout the DC Metro area) took part in a week-long, all-day workshop where they were exposed to female engineering mentors, peers, and activities tied to BME & engineering. Pre and post surveys, adapted from standard STEM surveys, were administered to the pool of participants. Increases in confidence and interest in engineering and decreased anxiety were observed following female high school students' participation in hands-on activities in BME.
Single-port surgical robots have gained popularity due to less patient trauma and quicker post-surgery recovery. However, due to limited access provided by a single incision, the miniaturization and maneuverability of...
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Single-port surgical robots have gained popularity due to less patient trauma and quicker post-surgery recovery. However, due to limited access provided by a single incision, the miniaturization and maneuverability of these robots still needs to be improved. In this paper, we propose the design of a single-port, dual-arm robotically steerable endoscope containing one steerable major cannula and two steerable minor cannulas. By integrating the proposed nine degrees-of-freedom (DoFs) robotically steerable endoscope with an industrial robotic arm and a joystick controller, this robotic system can potentially achieve intuitive, and remote multi-arm manipulation capability. We present the design of the robotically steerable endoscope consisting of tendon-driven joints controlled by a compact actuation system and derive the kinematic and static models. We validate the derived models using different kinematic trajectories with an average RMSE value of 0.98 mm and 0.66 mm for the distal tip position errors of the two steerable minor cannulas.
Recent investigations on electrokinetic (EK) flows have indicated turbulentlike flow can be realized by applying strong and high frequency ac electric field to flows with high-conductivity-gradient interface, even tho...
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Recent investigations on electrokinetic (EK) flows have indicated turbulentlike flow can be realized by applying strong and high frequency ac electric field to flows with high-conductivity-gradient interface, even though under low bulk flow Reynolds number. Relative to conventionally hydrodynamic turbulence in a high Reynolds number, the ac EK turbulent flow exhibits high randomness with stronger intermittency [Wang et al., Phys. Rev. E 93, 013106 (2016)]. The abnormally high intermittency could be attributed to the ascending probability density function of velocity gradients (dominated by small scale velocity structure function) far from the equilibrium state. By evaluating the intermittency of the ac EK turbulent flow with hierarchical structures, we astonishingly find the intermittency factor of hierarchical structures in SL94 law, i.e., β factor, which is commonly believed to be between 0 and 1, exhibits larger value than 1 in the ac EK turbulent flow. This result indicates the different hierarchical relations of flow structures in ac EK turbulence flow from that in the conventional hydrodynamic turbulence, as further illustrated by the probability density function of velocity structures among different spatial scales.
A natural fluid gait of the Icelandic horses is so called tölt. It is a gait without suspension which is characterized by a symmetrical four-beat with lateral sequence of footfalls. In this paper biomechanics of ...
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Heat exchangers are widely utilized in different thermal systems for diverse industrial aspects. The selection of HEx depends on the thermal efficiency, operating load, size, flexibility in operation, compatibility wi...
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We propose a ten-yearMars mission to establish Earth-independence and support efficient, safe, and sustainable science and exploration goals. The campaign begins with a series of precursor missions, starting with the ...
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ISBN:
(数字)9781624107054
ISBN:
(纸本)9781624107054
We propose a ten-yearMars mission to establish Earth-independence and support efficient, safe, and sustainable science and exploration goals. The campaign begins with a series of precursor missions, starting with the Artemis program, followed by robotic missions to performsite surveys and selection, de-risk technologies, and to start stockpiling in-situ water and propellant. Robotic Cargo Starships would depart first in 2035 to deliver and deploy approximately 5,800 tons of habitats, nuclear microreactors, farmmodules, manufacturing and ISRU systems. In 2040, two Crew Starships carrying 36 persons would land onMars to establish two close-proximity villages. The lifecycle cost is estimated at $81 billion, with a peak annual cost of $6.6 billion. To meet RASC-AL competition requirements, intended to motivate the exploration of highly self-reliant architecture concepts, resupply from Earth was constrained to only 5 metric tons every two years and minimum surface endurance was set at 7 years. The risks to human life and to critical systems increase exponentially over a minimally-resupplied, 7-10 year mission toMars. Our approach focused on identifying capabilities to mitigate known and unknown risks. Using a high-fidelity crew time model, we found that large architectures, with their economies of scale and productivity gains from specialization, are essential to robustly support the necessary capabilities. The model also shows that small 7-year missions of 12 persons or less cannot provide value in terms of free surface traverse time for science and exploration. Given the necessity of a large, complex architecture, we then sought out efficiencies and synergies (value engineering) in order to make the mission feasible and affordable. In the process, we identified more benefits that are enabled only by large missions, including the creation of a true community on Mars with sufficient social complexity for humans to thrive, and the geopolitically compelling option to inclu
Recent advances in the field of two-dimensional (2D) materials have led to new electronic and photonic devices enabled by their unique properties at atomic *** 2D materials into desired patterns on substrates is often...
Recent advances in the field of two-dimensional (2D) materials have led to new electronic and photonic devices enabled by their unique properties at atomic *** 2D materials into desired patterns on substrates is often an essential and foremost step for the optimum performance of the functional *** this regard,optical patterning of 2D materials has received enormous interest due to its advantages of high-throughput,site-specific,and on-demand *** years have witnessed scientific reports of a variety of optical techniques applicable to patterning 2D *** this minireview,we present the state-of-the-art optical patterning of 2D materials,including laser thinning,doping,phase transition,oxidation,and *** applications based on optically patterned 2D materials will be discussed as *** further developments,optical patterning is expected to hold the key in pushing the frontiers of manufacturing and applications of 2D materials.
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