Search results for " engineering"
showing 10 items of 38291 documents
Melt Processed PCL/PEG Scaffold with Discrete Pore Size Gradient for Selective Cellular Infiltration
2016
In order to develop scaffold able to mimic the natural gradient properties of tissues, biphasic and triphasic approaches were adopted. In this work, polycaprolactone/polyethylene glycol (PCL/PEG) scaffolds were prepared by using a combination of melt mixing and selective leaching without harmful solvents. The method permitted to develop three-layer scaffolds with high control of porosity and pore size. The mechanical properties were evaluated under physiological condition in order to simulate the real conditions of work. Co-culture of osteoblastic and fibroblastic mice cells were carried out in order to study the differential cellular permeation through the different pore size layers.
Three-layered porous device in PCL/PEG blend for interface tissue engineering
2016
Tissue interfaces, such as cartilage-to-bone, exhibit anisotropic structural properties, which gradually vary from one tissue to another. Consequently a regenerative scaffold designed for interface tissues should exhibit a gradient in composition, structure and mechanical features, mimicking those of the native zones. In particular, the architecture of pores plays a central role. Indeed, a biomedical implant should be designed with porosityand pore size gradients simulating the structure of the two interface tissues. One of the most common techniques to prepare porous scaffolds is the particulate leaching method, which involves the selective leaching of a mineral or organic compound as poro…
Enabling Energy Savings in Offshore Mechatronic Systems by using Self-Contained Cylinders
2019
This paper proposes a novel actuation system for an offshore drilling application. It consists of three self-contained electro-hydraulic cylinders that can share and store regenerated energy. The energy saving potential of the proposed solution is analyzed through a multibody system simulation. The self-contained system demonstrates superior energy efficiency compared to the benchmark system representing the state-of-the-art approach used today (i.e., valve-controlled cylinders by means of pressure-compensated directional control valves and counter-balance valves, supplied by a centralized hydraulic power unit). Due to the power on demand capability, the cancellation of the throttling losse…
Uncovering value through exploration of barriers:A perspective on intellectual property rights in a national innovation system
2023
Although for a long time policy has emphasized the role of intellectual property rights as a growth agent facilitating innovation, the literature has called into question this relationship. Critical studies have focused on studying policy frames and protection modes that could transform the intellectual property rights system to be more beneficial. Studies have not, however, focused on the intellectual property rights system stakeholders in cocreating the system. Our study contributes to the literature by uncovering the tensions in developing a national-level intellectual property rights strategy. Using the Delphi method, we draw from a broad stakeholder dialogue to show the barriers for in…
Giving patients secure " google-like " access to their medical record
2008
International audience; The main problem for the patient who wants to have access to all of the information about his health is that this information is very often spread over many medical records. Therefore, it would be convenient for the patient, after being identified and authenticated, to use a kind of specific medical search engine as one part of the solution to this main problem. The principal objective is for the patient to have access to his or her medical information at anytime and wherever it has been stored. This proposal for secure "Google Like" access requires the addition of different conditions: very strict identity checks using cryptographic techniques such as those planned …
Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEM) of a Customized Stent-Graft for Endovascular (EVAR) Treatment of Abdominal Aorti…
2023
Background: The treatment of abdominal aortic aneurysm (AAA) is today commonly treated by inserting a stent-graft by the endovascular route, without resorting to open surgery. However, some clinical cases do not allow this less invasive approach, meaning that the stent-graft cannot be inserted and open surgery is used. Methods: In the study, we propose a fluid–structure interaction (FSI) analysis of an aneurysmatic aorta that could not be treated with Endovascular Aneurysm Repair (EVAR). The vessel is reconstructed through segmentation from CT scans and subsequently modeled on CAD software to create the surface and thickness of the vessel itself. Subsequently, we proceeded to carry out Comp…
Cost optimal analysis of lighting retrofit scenarios in educational buildings in Italy
2017
Abstract The European Energy Performance of Buildings Directive (EPBD) recast proposes, a comparative methodology to calculate cost-optimal levels of minimum energy performance requirements for buildings. This paper presents a method able to select the best retrofit action for lighting system, selectively analysing the daylight conditions and applying the cost-optimal methodology for different scenarios proposed for two existing educational buildings located in Italy. With the aim to improve both energy efficient and visual comfort conditions, the retrofit scenarios include lighting solutions with different combinations. They consider the replacement of lamps with more efficient lighting so…
Optimization of BESS Capacity Under a Peak Load Shaving Strategy
2018
Battery energy storage systems (BESSs) are becoming increasingly competitive in the global energy landscape, thanks to the strong cost reduction that has taken place in recent years and it is expected to continue in the next future. Among the many benefits BESSs can provide, time shifting can be exploited by electricity consumers to save on the electricity bill, charging the storage during the off-peak hours and discharging when the cost of electricity is high. This paper describes a simple procedure to optimize the BESS capacity under a peak load shaving strategy, in presence of a time-of-use (TOU) electricity rate, able to guarantee, at the same time, the flattest daily power diagram and …
DEMAND Project: A Peak Load Shaving Strategy for End-User Consumers
2018
Battery energy storage systems (BESS) are becoming increasingly widespread in modern power systems, thanks to the important benefits they can provide to the electricity grid. Indeed, BESS can be used in time shifting applications, storing energy during off-peak periods and discharging during peak times (when the cost of electricity is high). When BESS are used for peak shaving purposes, they also contribute to relieve peak demand charges, thus ensuring a saving for the consumers. This paper describes a peak load shaving strategy defined within the DEMAND project. The strategy is able to guarantee the flattest daily power diagram and the maximum benefit for the electricity consumers, reducin…
Iterative Learning Applied to Hydraulic Pressure Control
2018
This paper addresses a performance limiting phenomenon that may occur in the pressure control of hydraulic actuators subjected to external velocity disturbances. It is demonstrated that under certain conditions a severe peaking of the control error may be observed that significantly degrades the performance of the system due to the presence of nonlinearities. The phenomenon is investigated numerically and experimentally using a system that requires pressure control of two hydraulic cylinders. It is demonstrated that the common solution of feed forwarding the velocity disturbance is not effective in reducing the peaking that occurs as a result of this phenomenon. To improve the system perfor…