PV panellerinin radyasyon miktarına bağlı olarak ısınması ve veriminin düşmesi bilinen ve üzerinde birçok çalışma yapılan bir olgudur. PV panellerin soğutulması için panel tabanına FDM eklenmesi ise ...literatürde yaygın olarak görülen bir pasif soğutma yöntemidir. Bu çalışmada ise PV panel tabanına FDM eklenmesi ve farklı hacim oranlarında FDM nanopartikül karışımı eklenmesi durumunda PV panel sıcaklığı, panel verimi, elektrik üretimi ve FDM konteynerindeki erime oranları 1-B matematiksel model kullanılarak incelenmiştir. Çalışma 800, 1000, 1200 W/m2 radyasyon değerleri için gerçekleştirilmiştir. Sonuçlar incelendiğinde en yüksek verim ve elektrik üretimi değerlerinin hacimce 0.5 nanopartikül PCM karışımı için elde edildiği görülmüştür. Verim ifadesi hacimce 0.5 nanopartikül karışımı için 800, 1000 ve 1200 W/m2 için sırasıyla % 18.3, %17.7 ve %17.2 olarak elde edilmiştir ki bu değerler geleneksel PV panelinden yaklaşık %1 fazladır. Eleltrik üretimi ise yine 0.5 nanopartikül FDM karışımı için sırasıyla 112.5, 128 ve 158 W olarak elde edilmiştir ve bu değerler geleneksel PV panelden sırasıyla 5, 7 ve 8 W daha fazladır.
PV panellerinin radyasyon miktarına bağlı olarak ısınması ve veriminin düşmesi bilinen ve üzerinde birçok çalışma yapılan bir olgudur. PV panellerin soğutulması için panel tabanına FDM eklenmesi ise literatürde yaygın olarak görülen bir pasif soğutma yöntemidir. Bu çalışmada ise PV panel tabanına FDM eklenmesi ve farklı hacim oranlarında FDM nanopartikül karışımı eklenmesi durumunda PV panel sıcaklığı, panel verimi, elektrik üretimi ve FDM konteynerindeki erime oranları 1-B matematiksel model kullanılarak incelenmiştir. Çalışma 800, 1000, 1200 W/m2 radyasyon değerleri için gerçekleştirilmiştir. Sonuçlar incelendiğinde en yüksek verim ve elektrik üretimi değerlerinin hacimce 0.5 nanopartikül PCM karışımı için elde edildiği görülmüştür. Verim ifadesi hacimce 0.5 nanopartikül karışımı için 800, 1000 ve 1200 W/m2 için sırasıyla % 18.3, %17.7 ve %17.2 olarak elde edilmiştir ki bu değerler geleneksel PV panelinden yaklaşık %1 fazladır. Eleltrik üretimi ise yine 0.5 nanopartikül FDM karışımı için sırasıyla 112.5, 128 ve 158 W olarak elde edilmiştir ve bu değerler geleneksel PV panelden sırasıyla 5, 7 ve 8 W daha fazladır.
Bei urheberrechtlichen Fragen im Forschungsdatenmanagement stehen Forschende und Beratungspersonal vor besonderen Herausforderungen. Einerseits verlangt die gute wissenschaftliche Praxis, mögliche ...Urheber- und Leistungsschutzrechte an Forschungsdaten frühzeitig zu klären, zum Beispiel durch Verträge zwischen Projektbeteiligten oder durch institutionelle Richtlinien. Andererseits ist die Rechtslage im Forschungsalltag oft sehr komplex und es mangelt an Unterstützung bei der Formulierung der notwendigen Vereinbarungen. Dieser Übersichtsartikel führt kurz in die für Forschungsdaten relevanten Aspekte des Urheberrechts ein und zeigt anhand zweier Fallbeispiele häufig vorkommende Unsicherheiten auf. Wir regen an, Muster- und Beispieltexte, die das Urheberrecht betreffen, in einem koordinierten, einrichtungsübergreifenden Prozess zu entwickeln und zentral zur Nachnutzung zur Verfügung zu stellen. Außerdem schlagen wir vor, ein Online-Unterstützungsangebot aufzubauen, das bei der Klärung urheberrechtlicher Fragen hilft und der Weiterentwicklung und Kommentierung bestehender Musterdokumente dient.
Mobile fronthaul is an important network segment that bridges wireless baseband units and remote radio units to support cloud radio access network. We review recent progresses on the use of ...frequency-division multiplexing to achieve highly bandwidth-efficient mobile fronthaul with low latency. We present digital signal processing (DSP) techniques for channel aggregation and deaggregation, frequency-domain windowing, adjacent channel leak age ratio reduction, and synchronous transmission of both the I/Q waveforms of wireless signals and the control words (CWs) used for control and management purposes. In a proof-of-concept experiment, we demonstrate the transmission of 48 20-MHz LTE signals with a common public radio interface (CPRI) equivalent data rate of 59 Gb/s, achieving a low round-trip DSP latency of <;2 μs and a low mean error-vector magnitude (EVM) of ~2.5% after fiber transmission. In a follow-up experiment, we further demonstrate the transmission of 32 20-MHz LTE signals together with CPRI-compliant CWs, corresponding to a CPRI-equivalent data rate of 39.32 Gb/s, in single optical wavelength channel that requires an RF bandwidth of only ~1.6 GHz. After transmission over 5-km standard single-mode fiber, the CWs are recovered without error, while the LTE signals are recovered with an EVM of lower than 3%. Applying this technique to future 5G wireless networks with massive multiple-input multiple-output is also discussed. This efficient mobile fronthaul technique may find promising applications in future integrated fiber/wireless access networks to provide ultrabroadband access services.
Three-dimensional printing is one of the emerging technologies that is gaining interest from the pharmaceutical industry as it provides an opportunity to customize drugs according to each patient's ...needs. Combining different active pharmaceutical ingredients, using different geometries, and providing sustained release enhances the effectiveness of medicine. One of the most innovative uses of 3D printing is producing fabrics, medical devices, medical implants, orthoses, and prostheses. This review summarizes the various 3D printing techniques such as stereolithography, inkjet printing, thermal inkjet printing, fused deposition modelling, extrusion printing, semi-solid extrusion printing, selective laser sintering, and hot-melt extrusion. Also, discusses the drug relies profile and its mechanisms, characteristics, and applications of the most common types of 3D printed API formulations and its recent development. Here, Authors also, summarizes the central flow of 3D food printing process and knowledge extension toward personalized nutrition.
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•Summarized the mechanisms, characteristics, and applications of 3D printing technologies•Discussed 3D printing methods to develop pharmaceutical drugs and their significant drug load and delivery•Highlights different 3D printing drug delivery devices•Summarized the process of 3D food printing in relation to personalized nutrition and its commercial developments.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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STUDY ON OPTIMIZING MATERIALS FOR 3D GRIPPER PRINTING Paduraru, Emilian; Dumitras, Catalin Gabriel; Chitariu, Dragos Florin ...
International Journal of Modern Manufacturing Technologies,
12/2022, Volume:
14, Issue:
2
Journal Article
The purpose of this paper is to identify the material that offers optimal characteristics in terms of cost, strength and weight. This is necessary because more and more composite materials and 3D ...printing are being used in the construction of robots, including the gripper. In this context, two types of materials are considered possible to be used in the construction of grippers. Samples are made in different 3D printing modes; the Taguchi method is applied to identify the optimal values. A finite element analysis was also performed in order to verify the characteristics of the materials introduced in the program by comparison with the experimental results in order to use them in the analysis of a new gripper solution. As they will follow, PLA material with 100% infill, 0,17mm layers thickness and 45° raster angle has the greatest resistance at extension. This material definition will be used in future research to the entire model of the gripper to see the behavior in different conditions given by the current requirements.
The employment of tissue engineering scaffolds in the reconstruction of the damaged bone tissues has shown remarkable promise since they significantly facilitate the healing process. Fabrication of ...highly porous biocompatible scaffolds with sufficient mechanical strength is still challenging. In this regard, polymers have been widely utilized to construct three-dimensional (3D) porous scaffolds due to their excellent processability and biocompatibility. However, insufficient mechanical strength and inappropriate degradation rate of the monophasic polymer scaffolds in the bone regeneration process, as the main challenges, limit their extensive clinical application. The incorporation of metallic fillers into the polymer matrix has been shown to be helpful due to their strengthening effect and magnificent impact on the biological properties of the polymer-based 3D porous scaffolds, including cell viability, osteogenic, angiogenic and antibacterial properties. In this paper, fabrication of the polymer/metal composite 3D porous scaffolds by additive manufacturing techniques, as the most convenient approache to construct complex polymer-based parts, their structural, mechanical, biodegradation, biocompatibility, osteogenic and angiogenic features have been reviewed. Furthermore, new perspectives have been proposed to promote the implementation of polymer/metal composite scaffolds in bone tissue engineering practices.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Fused deposition modelling (FDM) is one of the fastest-growing additive manufacturing methods used in printing fibre-reinforced composites (FRC). The performances of the resulting printed parts are ...limited compared to those by other manufacturing methods due to their inherent defects. Hence, the effort to develop treatment methods to overcome these drawbacks has accelerated during the past few years. The main focus of this study is to review the impact of those defects on the mechanical performance of FRC and therefore to discuss the available treatment methods to eliminate or minimize them in order to enhance the functional properties of the printed parts. As FRC is a combination of polymer matrix material and continuous or short reinforcing fibres, this review will thoroughly discuss both thermoplastic polymers and FRCs printed via FDM technology, including the effect of printing parameters such as layer thickness, infill pattern, raster angle and fibre orientation. The most common defects on printed parts, in particular, the void formation, surface roughness and poor bonding between fibre and matrix, are explored. An inclusive discussion on the effectiveness of chemical, laser, heat and ultrasound treatments to minimize these drawbacks is provided by this review.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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As a core technology in the field of high and new tech manufacturing,3D printing occupies an important position in the production process of aviation, shipbuilding, and automobiles. With the ...rapid development of 3D printing basic theory in recent years, how to further improve product accuracy, quality and modeling efficiency has become the current research focus in this field. Firstly, we conducted further research on the key technologies of FDM 3D printer, and combining 3D reconstruction technology with pretreatment technology. Secondly, we constructed and optimized the corresponding model layered slice and filling path planning algorithm. Thirdly, we designed a 3D suitable for rapid prototyping products printing control system. The research can provide an effective experience for the application of 3D printing technologies.
Additive manufacturing technologies provide new opportunities for the manufacturing of components with customisable geometries and mechanical properties. In particular, fused deposition modelling ...(FDM) allows for customisable mechanical properties by controlling the void density and filament orientation. In this work, a methodology is provided for the prediction of the mechanical properties and mesostructure of FDM polymers. To this end, we propose a computational framework for the simulation of the printing process taking as input data specific manufacturing parameters and filament properties. A new two-stage thermal and sintering model is developed to predict the bond formation process between filaments. The model predictions are validated against original experimental data for acrylonitrile butadiene styrene (ABS) components manufactured by FDM. A parametric study is finally presented to interpret the effects of different manufacturing parameters on the mechanical performance of ABS specimens. Overall, the proposed framework offers new avenues for the design of 3D printed polymeric components with custom properties, directly in terms of manufacturing settings.
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•FDM ABS specimens are tested for different combinations of printing parameters.•A two-stage model is proposed to simulate the FDM manufacturing process.•The model predicts thermal conditions and sintering within filaments.•Analytical expressions are established for FDM ABS.•Layer height and environment temperature main drivers for mechanical properties.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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