A growing number of three-dimensional(3D)-print- ing processes have been applied to tissue engineering. This paper presents a state-of-the-art study of 3D-printing technologies for tissue-engineering applications, wit...A growing number of three-dimensional(3D)-print- ing processes have been applied to tissue engineering. This paper presents a state-of-the-art study of 3D-printing technologies for tissue-engineering applications, with particular focus on the development of a computer-aided scaffold design system; the direct 3D printing of functionally graded scaffolds; the modeling of selective laser sintering(SLS) and fused deposition modeling(FDM) processes; the indirect additive manufacturing of scaffolds, with both micro and macro features; the development of a bioreactor; and 3D/4D bioprinting. Technological limitations will be discussed so as to highlight the possibility of future improvements for new 3D-printing methodologies for tissue engineering.展开更多
Three dimensional （3D） printing technology was utilized to fabricate a new type of drug implant with complicated architectures, employing levofloxacin （LVFX） and rifampicine （RFP） as model drugs. The prepared dr...Three dimensional （3D） printing technology was utilized to fabricate a new type of drug implant with complicated architectures, employing levofloxacin （LVFX） and rifampicine （RFP） as model drugs. The prepared drug implant prototype consists of a doublelayer structure, of which the upper region is a reservoir system containing RFP and the lower region is a matrix one containing LVFX. The release test in vivo revealed that LVFX was released in the early stage; no RFP was detected until 8th day; both of them continuously released more than 6 weeks. Therefore, 3D printing technology provides a precise and feasible method to fabricate a controlled-releasing drug implant with complicated architectures and this drug implant may present a new strategy for the prophylaxis and treatment of bone diseases such as combined bone infections and bone tuberculosis in the near future.展开更多
3D printing is a rapid prototyping technology to shape materials or objects through printing layer by layer driven by digital models, which can be adopted for the manufacture of refractory precast components. Thus, th...3D printing is a rapid prototyping technology to shape materials or objects through printing layer by layer driven by digital models, which can be adopted for the manufacture of refractory precast components. Thus, the production technology of refractory precast components as well as the technique and advantages of 3D printing was introduced. The feasibility and application prospect of 3D printing concrete, contour crafting and adhesive 3D printing in refractory precast components were presented.展开更多
3D printing can spur manufacturing rebirth in Nigeria and the World in general. There are many areas where 3D printing is creating significant change, particularly in designing and prototyping of new products, in the ...3D printing can spur manufacturing rebirth in Nigeria and the World in general. There are many areas where 3D printing is creating significant change, particularly in designing and prototyping of new products, in the arts, and in visualizing abstract concepts. This is a step change from conventional manufacturing processes to rapid prototyping and layer manufacturing. This report has defined rapid prototyping, rapid manufacturing and the current technologies available to fabricate 3D components. In addition to this, it provides a brief overview of the current contributions of the Edo University Iyamho (EUI) in collaboration with the Federal University of Petroleum Resources, to sustain manufacturing research initiatives towards the development of locally fabricated 3D printer and the possible future Additive Manufacturing in Nigeria. It is anticipated that this work will benefit the Nigerian academic, research institutes, industries, thus, enhance the GDP contribution of the manufacturing sector in Nigeria.展开更多
Part orientation is one of the important factors in manufacturing with three dimensional printing (3DP) of rapid prototyping system. The minimum building time, being achieved by the part’s minimum building height and...Part orientation is one of the important factors in manufacturing with three dimensional printing (3DP) of rapid prototyping system. The minimum building time, being achieved by the part’s minimum building height and minimum width in 3DP’s y direction, is set as the objective of optimizing the part orientation. Genetic algorithm is adopted to find the minimum building height of parts and then ergodic searching is used to get the minimum width of part in y direction. A corresponding program for optimizing part orientation in 3DP was developed. Tests show the proposed approach is effective and fast.展开更多
Experiment of rapid prototyping (RP) is a multi-level and multi-factor problem with long process cycle. As powder-based RP method, three dimensional printing (3DP), and selective laser sintering (SLS) are the most pro...Experiment of rapid prototyping (RP) is a multi-level and multi-factor problem with long process cycle. As powder-based RP method, three dimensional printing (3DP), and selective laser sintering (SLS) are the most prominent RP methods for their flexibility in material selecting. The research of 3DP process shows that much experiments work can be greatly decreased by the method of uniform design with restricted mixtures for RP products’ performance to its forming material. Then, according to backward regression methods, the binomial and inverse terms nonlinear regression equations were set up by statistic analysis and computation. Together with evaluation function method, multi-object optimization model for performance of products to the powder mixtures was developed, and the optimization problem was solved by software MATLAB. After that, the optimum results were solved and tested by experiment with the same condition as before. Differences between the calculation results and testing results, which including product’s density, compression strength, surface evaluation, and deformation in three dimensions, are less than 10%, and have the same error direction. Uniform design method for regression and optimization was proved to be an excellent method to obtain optimum results for multi-level and multi-factor experiments of RP and other process which have a long processing cycle.展开更多
基金Singapore National Research Foundation (NRF) for funding the Singapore Centre for 3D Printing (SC3DP)
文摘A growing number of three-dimensional(3D)-print- ing processes have been applied to tissue engineering. This paper presents a state-of-the-art study of 3D-printing technologies for tissue-engineering applications, with particular focus on the development of a computer-aided scaffold design system; the direct 3D printing of functionally graded scaffolds; the modeling of selective laser sintering(SLS) and fused deposition modeling(FDM) processes; the indirect additive manufacturing of scaffolds, with both micro and macro features; the development of a bioreactor; and 3D/4D bioprinting. Technological limitations will be discussed so as to highlight the possibility of future improvements for new 3D-printing methodologies for tissue engineering.
基金Funded by the Graduate Innovation Fund of the Huazhong University of Science and Technology, the "863" Key Project of the National High Technology Research and Development Program of China (No.2006AA02A124)the Program for New Century Excellent Talents in University from the Ministry of Education of China( NCET-05-0647)
文摘Three dimensional （3D） printing technology was utilized to fabricate a new type of drug implant with complicated architectures, employing levofloxacin （LVFX） and rifampicine （RFP） as model drugs. The prepared drug implant prototype consists of a doublelayer structure, of which the upper region is a reservoir system containing RFP and the lower region is a matrix one containing LVFX. The release test in vivo revealed that LVFX was released in the early stage; no RFP was detected until 8th day; both of them continuously released more than 6 weeks. Therefore, 3D printing technology provides a precise and feasible method to fabricate a controlled-releasing drug implant with complicated architectures and this drug implant may present a new strategy for the prophylaxis and treatment of bone diseases such as combined bone infections and bone tuberculosis in the near future.
文摘3D printing is a rapid prototyping technology to shape materials or objects through printing layer by layer driven by digital models, which can be adopted for the manufacture of refractory precast components. Thus, the production technology of refractory precast components as well as the technique and advantages of 3D printing was introduced. The feasibility and application prospect of 3D printing concrete, contour crafting and adhesive 3D printing in refractory precast components were presented.
文摘3D printing can spur manufacturing rebirth in Nigeria and the World in general. There are many areas where 3D printing is creating significant change, particularly in designing and prototyping of new products, in the arts, and in visualizing abstract concepts. This is a step change from conventional manufacturing processes to rapid prototyping and layer manufacturing. This report has defined rapid prototyping, rapid manufacturing and the current technologies available to fabricate 3D components. In addition to this, it provides a brief overview of the current contributions of the Edo University Iyamho (EUI) in collaboration with the Federal University of Petroleum Resources, to sustain manufacturing research initiatives towards the development of locally fabricated 3D printer and the possible future Additive Manufacturing in Nigeria. It is anticipated that this work will benefit the Nigerian academic, research institutes, industries, thus, enhance the GDP contribution of the manufacturing sector in Nigeria.
基金the Natural Science Foundation Hubei Province, China (2005ABA181)
文摘Part orientation is one of the important factors in manufacturing with three dimensional printing (3DP) of rapid prototyping system. The minimum building time, being achieved by the part’s minimum building height and minimum width in 3DP’s y direction, is set as the objective of optimizing the part orientation. Genetic algorithm is adopted to find the minimum building height of parts and then ergodic searching is used to get the minimum width of part in y direction. A corresponding program for optimizing part orientation in 3DP was developed. Tests show the proposed approach is effective and fast.
基金Supported by the Ph. D’s Start-up Fund in University of Shanghai for Science and Technology, China (No. 10D305)
文摘Experiment of rapid prototyping (RP) is a multi-level and multi-factor problem with long process cycle. As powder-based RP method, three dimensional printing (3DP), and selective laser sintering (SLS) are the most prominent RP methods for their flexibility in material selecting. The research of 3DP process shows that much experiments work can be greatly decreased by the method of uniform design with restricted mixtures for RP products’ performance to its forming material. Then, according to backward regression methods, the binomial and inverse terms nonlinear regression equations were set up by statistic analysis and computation. Together with evaluation function method, multi-object optimization model for performance of products to the powder mixtures was developed, and the optimization problem was solved by software MATLAB. After that, the optimum results were solved and tested by experiment with the same condition as before. Differences between the calculation results and testing results, which including product’s density, compression strength, surface evaluation, and deformation in three dimensions, are less than 10%, and have the same error direction. Uniform design method for regression and optimization was proved to be an excellent method to obtain optimum results for multi-level and multi-factor experiments of RP and other process which have a long processing cycle.
