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An improved mass addition approach based on enthalpy balance is used for the numerical simulation of the temperature distributions and geometries during laser rapid manufacturing (LRM) of a multi-layered thin-wall. The approach in...
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An improved mass addition approach based on enthalpy balance is used for the numerical simulation of the temperature distributions and geometries during laser rapid manufacturing (LRM) of a multi-layered thin-wall. The approach involves the estimation of the local track height at every node along the track width on the substrate/previously deposited layer by simultaneous balancing of the excessive enthalpies above solidus temperature about the laser axis and the material interface at the substrate/previously deposited layer for material addition during the laser rapid manufacturing of a multi-layer thin wall. It takes laser power, laser beam size, scan-speed, powder feed rate, powder stream diameter, and time-delay between the deposition of two subsequent tracks as user-defined input, and computes the temperature distributions and the geometries of the deposited layers across the process domain in a dynamic fashion. In the present study, the laser rapid manufacturing of five layered thin walls of SS 304L on a work piece of the same material was simulated for various combinations of processing parameters and compared with experimental results. The percentage errors in simulated and corresponding experimental cumulative track heights along with track width were calculated and compared with those of other existing models and the results of present approach were found to be the least. The result indicates that the height and width of the layer under deposition depends on the geometry and temperature distribution of previously deposited layer and, consequently, governed the final geometry of thin wall.
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In general, inorganic dielectric materials are being used to fabricate multi-layer-coated mirrors. Their fabricating methods are almost all based on vacuum evaporation or vacuum sputtering, whose apparatus cost so high. On the oth...
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In general, inorganic dielectric materials are being used to fabricate multi-layer-coated mirrors. Their fabricating methods are almost all based on vacuum evaporation or vacuum sputtering, whose apparatus cost so high. On the other hand, polymeric thin-films such as photo-resists and planar waveguides can be easily obtained by spin coating and casting. In this study, we report the results of fabrication of multi-layer-coated mirrors by spin coating of two different polymers.
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We develop the multi-layer multi-configuration time-dependent Hartree method for bosons (ML-MCTDHB), a variational numerically exact ab initio method for studying the quantum dynamics and stationary properties of general bosonic s...
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We develop the multi-layer multi-configuration time-dependent Hartree method for bosons (ML-MCTDHB), a variational numerically exact ab initio method for studying the quantum dynamics and stationary properties of general bosonic systems. ML-MCTDHB takes advantage of the permutation symmetry of identical bosons, which allows for investigations of the quantum dynamics from few to many-body systems. Moreover, the multi-layer feature enables ML-MCTDHB to describe mixed bosonic systems consisting of arbitrary many species. Multi-dimensional as well as mixed-dimensional systems can be accurately and efficiently simulated via the multi-layer expansion scheme. We provide a detailed account of the underlying theory and the corresponding implementation. We also demonstrate the superior performance by applying the method to the tunneling dynamics of bosonic ensembles in a one-dimensional double well potential, where a single-species bosonic ensemble of various correlation strengths and a weakly interacting two-species bosonic ensemble are considered.
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Polymer light-emitting diodes, which possess a multi-layer structure and produce blue, green and red emissions on an ITO substrate, were successfully fabricated. The basic device structure is ITO/PEDOT/blue polymer/Ba/Al/green pol...
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Polymer light-emitting diodes, which possess a multi-layer structure and produce blue, green and red emissions on an ITO substrate, were successfully fabricated. The basic device structure is ITO/PEDOT/blue polymer/Ba/Al/green polymer/Ba/Al/red polymer/Ba/Al, where PEDOT is poly(styrene sulfonic acid), functioning as the hole transportation, injection, and ITO surface modification, Ba: barium electron injection cathode, Al: aluminum, acting as the protecting layer from Ba oxidized. All polymer layers were prepared by spin-coating technique. The blue, green and red emission intensities can separately be controlled. Possible electroluminescence (EL) mechanisms were discussed in this paper.
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Although the phytotoxicity of graphene-based materials has been investigated extensively, the effects of different graphene-based materials on nutrient uptake in plants remain unclear. Here, we analyzed the differences in phytotox...
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Although the phytotoxicity of graphene-based materials has been investigated extensively, the effects of different graphene-based materials on nutrient uptake in plants remain unclear. Here, we analyzed the differences in phytotoxicity between single-layer graphene oxide (sGO) and multi-layer graphene oxide (mGO) by analyzing the growth status and nitrate (NO 3 – ) accumulation in wheat plants at 0, 100, 200, 400, and 800?mg?L ?1 graphene oxide supply. Both sGO and mGO displayed concentration-dependent inhibitory effects on biomass, root length, number of lateral roots, and nitrogen (N) nutrient status. Treatment with 400?mg?L ?1 sGO caused 0.9-, 1.3-, and 1-fold higher reductions in NO 3 – -N, assimilated N, and total N concentrations in roots, respectively, than mGO treatment. Analysis of root oxidative stress and in situ NO 3 – uptake revealed that sGO caused more significant damage to the root tip and a lower NO 3 – net influx rate than mGO. In addition, the expression of NO 3 – transporter (NRT) genes in roots, including NRT1.5 , NRT2.1 , NRT2.2 , NRT2.3 , and NRT2.4 , under sGO treatment were lower than those under mGO treatment. Overall, sGO treatment induced a more severe inhibitory effect on root growth and NO 3 – uptake and accumulation than mGO treatment, accompanied by significant suppression of the expression of NRTs in sGO-treated roots. This study provides a physiological and molecular basis for studying the phytotoxic effects of various sizes of graphene oxide.
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This paper describes a series of reduced scale tests, at unit gravity, performed on circular footings supported by reinforced sand. Reinforcement by multiple layers of geocell was investigated and the performance of the footing wa...
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This paper describes a series of reduced scale tests, at unit gravity, performed on circular footings supported by reinforced sand. Reinforcement by multiple layers of geocell was investigated and the performance of the footing was compared to one on the same sandy soil containing multi-layered planar geotextile reinforcement. The comparison used geocell and geotextile layers formed from the same parent geosynthetic material having the same characteristics but with a lower geocell mass. Results show that the efficiency of the reinforcement (described in terms of the load carrying and subgrade modulus enhancement) decreased as the number of layers increased. In tests at moderate and low footing settlements, significant improvements in bearing capacity and subgrade modulus were obtained with the application of three layers of geocell. On the whole, multi-layered geocell-reinforced soil provides a more effective and much stiffer system capable of delivering greater foundation loads and subgrade modulus than multi-layered planar reinforced soil, even when less parent geosynthetic material is used in the multi-layered geocell arrangement. Furthermore, reinforcement benefit is achievable at settlements as small as 0.2-0.4% of the footing diameter for the geocell installations, whereas settlements 4 to 5 times larger are needed before benefit is gained from a comparable planar geotextile system. To achieve comparable performances, the multi-layered geocell requires 1/4 to 1/2 the mass of geosynthetic material as that needed for multi-layered planar geotextile reinforcement (depending on the settlement allowable). The multi layered geocell reinforcement requires considerably less parent geosynthetic material (reducing transport and, perhaps supply costs), and because the size of reinforcement zone required is considerably smaller, the amount of excavation and backfill required is also significantly reduced. (C) 2017 The Japanese Geotechnical Society. Production and hosting by Elsevier B.V.
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A new structure of multi-layer phosphor package of white-light-emitting diodes has been proposed. The thickness of phosphor layer plays an important role in improving the efficiency of LED and the calculation has showed that the e...
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A new structure of multi-layer phosphor package of white-light-emitting diodes has been proposed. The thickness of phosphor layer plays an important role in improving the efficiency of LED and the calculation has showed that the efficiency of double-layer and triple-layer phosphor package improves a lot and the multi-layer phosphor package also has higher efficiency.
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This paper proposes an encoding method to hide multiple covert images in multiple layers into a host image to form an overt image. The codes encoded in the overt image are classified into five groups, identification codes, image n...
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This paper proposes an encoding method to hide multiple covert images in multiple layers into a host image to form an overt image. The codes encoded in the overt image are classified into five groups, identification codes, image number codes, graylevel codes, dimension codes, and information codes. Identification codes are used to determine whether the overt image contains codes proposed in this paper or not; image number codes are used to indicate the number of covert images encoded in the overt image; graylevel codes are used to indicate the graylevel numbers of covert images; dimension codes are used to determine the sizes of covert images; information codes are used to decode covert images. Moreover, a covert image in an upper layer can hide several other covert images in a lower layer. The codes encoded in an upper-layer covert image are classified into four groups, image number codes, graylevel codes, dimension codes, and information codes. The host image and keys are not needed for decoding and all the reconstructed covert images do not contain any distortion when the proposed encoding method is used. The designer can quickly decode covert images, but people without authorization cannot successfully decode covert images. Moreover, the overt image looks almost the same as the host image.
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Multi-layer networks of multiplex type represent relational data on a set of entities (nodes) with multiple types of relations (edges) among them where each type of relation is represented as a network layer. A large group of popu...
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Multi-layer networks of multiplex type represent relational data on a set of entities (nodes) with multiple types of relations (edges) among them where each type of relation is represented as a network layer. A large group of popular community detection methods in networks are based on optimizing a quality function known as the modularity score, which is a measure of the extent of presence of module or community structure in networks compared to a suitable null model. Here we introduce several multi-layer network modularity and model likelihood quality function measures using different null models of the multi-layer network, motivated by empirical observations in networks from a diverse field of applications. In particular, we define multi-layer variants of the Chung-Lu expected degree model as null models that differ in their modeling of the multi-layer degrees. We propose simple estimators for the models and prove their consistency properties. A hypothesis testing procedure is also proposed for selecting an appropriate null model for data. These null models are used to define modularity measures as well as model likelihood based quality functions. The proposed measures are then optimized to detect the optimal community assignment of nodes (Code available at: ). We compare the effectiveness of the measures in community detection in simulated networks and then apply them to four real multi-layer networks.
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