The Experts below are selected from a list of 189 Experts worldwide ranked by ideXlab platform
Yin Yu - One of the best experts on this subject based on the ideXlab platform.
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Bioprinting toward organ fabrication: Challenges and future trends
IEEE Transactions on Biomedical Engineering, 2013Co-Authors: Ibrahim T. Ozbolat, Yin YuAbstract:Tissue engineering has been a promising field of research, offering hope for bridging the gap between organ shortage and transplantation needs. However, building three-dimensional (3-D) vascularized organs remains the main Technological Barrier to be overcome. Organ printing, which is defined as computer-aided additive biofabrication of 3-D cellular tissue constructs, has shed light on advancing this field into a new era. Organ printing takes advantage of rapid prototyping (RP) technology to print cells, biomaterials, and cell-laden biomaterials individually or in tandem, layer by layer, directly creating 3-D tissue-like structures. Here, we overview RP-based bioprinting approaches and discuss the current challenges and trends toward fabricating living organs for transplant in the near future.
Molinari L. Tosatti - One of the best experts on this subject based on the ideXlab platform.
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Safe obstacle avoidance for industrial robot working without fences
2009 IEEE RSJ International Conference on Intelligent Robots and Systems, 2009Co-Authors: N. Pedrocchi, M. Malosio, Molinari L. TosattiAbstract:Until now, the presence of fences is a Technological Barrier for the adoption of robots in small medium enterprises (SME). The work deals with the definition of an intrinsically safe algorithm to avoid collisions between an industrial manipulator and obstacles in its workspace (Standard ISO 10218-1). The suggested strategy aims to offer an industrial solution to the problem: an off-line analysis of the workspace is performed to have an exhaustive and intrinsically description of the static obstacles and a safe spatial grid of ¿pass-through points¿ is calculated; an on-line algorithm, based on an enhanced artificial potential field evaluates the most suitable points to avoid collisions against obstacles and perform a realtime replanning the path of the robot. A Matlab toolbox that elaborates STL CAD files has been developed to obtain a full description of the workcell, and the avoidance algorithm has been designed and implemented in a standard industrial controller. Various experimental results are reported by using a COMAU NS16 arm manipulator.
Georges Descombes - One of the best experts on this subject based on the ideXlab platform.
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Thermal Electricity Storage by a Thermodynamic Process: Study of Temperature Impact on the Machines
Energy Procedia, 2013Co-Authors: Christelle Périlhon, Stéphanie Lacour, Pierre Podevin, Georges DescombesAbstract:This paper presents different ways of storing electricity to overcome the intermittency of renewable energies. After reviewing existing storage technologies, a new way of storing electricity thermodynamically on a large scale is presented. This system is based on the principle of a high temperature heat pump that converts electricity into heat. This thermal energy is stored in refractory materials, and at a later stage converted into electricity by means of a Joule cycle. The first mode -of energy storage- requires the use of turbomachinery - compressors and turbines - to operate under conditions different from those usually encountered. In particular, for the process to be efficient, the compressor must operate at high temperatures (500 to 1000° C). This represents a major Technological Barrier in the process due to the market unavailability of compressors capable of operating under such conditions. In this study the latest advances in the field of gas turbines are presented, including those concerning high pressure turbine blades, in order to adapt them to the compressor. These advances result mainly in changes in the composition of nickel-based superalloys and their implementation (single crystals) to achieve maximum wall temperatures around 950 °C.
Adam T. Clare - One of the best experts on this subject based on the ideXlab platform.
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Review of in-situ process monitoring and in-situ metrology for metal additive manufacturing
Materials and Design, 2016Co-Authors: Sarah K Everton, Matthias Hirsch, Petros I. Stavroulakis, Richard K Leach, Adam T. ClareAbstract:Lack of assurance of quality with additively manufactured (AM) parts is a key Technological Barrier that prevents manufacturers from adopting AM technologies, especially for high-value applications where component failure cannot be tolerated. Developments in process control have allowed significant enhancement of AM techniques and marked improvements in surface roughness and material properties, along with a reduction in inter-build variation and the occurrence of embedded material discontinuities. As a result, the exploitation of AM processes continues to accelerate. Unlike established subtractive processes, where in-process monitoring is now commonplace, factory-ready AM processes have not yet incorporated monitoring technologies that allow discontinuities to be detected in process. Researchers have investigated new forms of instrumentation and adaptive approaches which, when integrated, will allow further enhancement to the assurance that can be offered when producing AM components. The state-of-the-art with respect to inspection methodologies compatible with AM processes is explored here. Their suitability for the inspection and identification of typical material discontinuities and failure modes is discussed with the intention of identifying new avenues for research and proposing approaches to integration into future generations of AM systems.
Lew P. Christopher - One of the best experts on this subject based on the ideXlab platform.
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Thermophilic Hydrogen Production from Renewable Resources: Current Status and Future Perspectives
BioEnergy Research, 2012Co-Authors: Suvarna Talluri, Lew P. ChristopherAbstract:Hydrogen (H_2) is considered an alternative fuel of the future due to its high energy density and non-polluting nature. H_2 energy provides many advantages over fossil fuels in that it is renewable, eco-friendly, and efficient. The global demand for H_2 is increasing significantly; however, matching the supply of cost-competitive H_2 to meet the current demand is a major Technological Barrier. H_2 can be produced from lignocellulosic biomass and serve as a raw material for the synthesis of many industrially important chemicals. The use of thermophilic bacteria for biological production of H_2 appears to be a promising alternative route to the current H_2 production technologies. However, the carbon and H_2 production metabolisms in most thermophilic bacteria have not yet been completely understood. This paper summarizes the recent research progress made toward understanding the carbon utilization for H_2 production and developing gene manipulation techniques to enhance the H_2 production capabilities in thermophilic bacteria. It reviews the current status, future directions and opportunities that thermophiles can offer to enable a cost-competitive and environmentally benign H_2 production bioprocess.
