48 resultados para 3-DIMENSIONAL ISLAND FORMATION


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Abstract : This presentation will focus on design, modularity, development and control of a highly interactive programmable surface created within the CISR. The system is comprised of thousands of pneumatic cylinders controlled simultaneously in real-time to create a highly dynamic and responsive 3 dimensional surface. The idea behind this research project was the creation of a dynamically responsive surface that configures in real-time according to input from a variety of electronic inputs (movements, sound, etc). The surface is also viewed potentially as a universal motional simulator platform. A simulator that was developed for ease of system reconfiguration demonstrates the translation of complex mathematical functions into 3D shapes in the virtual world before being generated on the real surface. Application areas span from optical telescope to product manufacturing and giant 3D screens billboards for advertising and artwork.

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Stability charts for soil slopes, first produced in the first half of the twentieth century, continue to be used extensively as design tools, and draw the attention of many investigators. This paper uses finite-element upper and lower bound limit analysis to assess the short-term stability of slopes in which the slopematerial and subgrade foundation material have two distinctly different undrained strengths. The stability charts are proposed, and the exact theoretical solutions are bracketed to within 4.2% or better. In addition, results from the limit-equilibrium method (LEM) have been used for comparison. Differences of up to 20% were found between the numerical limit analysis and LEM solutions. It also shown that the LEM sometimes leads to errors, although it is widely used in practice for slope stability assessments.

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CONTEXT: Accelerometer peak impact accelerations are being used to measure player physical demands in contact sports. However, their accuracy to do so has not been ascertained. PURPOSE: To compare peak-impact-acceleration data from an accelerometer contained in a wearable tracking device with a 3-dimensional motion-analysis (MA) system during tackling and bumping. METHODS: Twenty-five semielite rugby athletes wore a tracking device containing a 100-Hz triaxial accelerometer (MinimaxX S4, Catapult Innovations, Australia). A single retroreflective marker was attached to the device, with its position recorded by a 12-camera MA system during 3 physical-collision tasks (tackle bag, bump pad, and tackle drill; N = 625). The accuracy, effect size, agreement, precision, and relative errors for each comparison were obtained as measures of accelerometer validity. RESULTS: Physical-collision peak impact accelerations recorded by the accelerometer overestimated (mean bias 0.60 g) those recorded by the MA system (P < .01). Filtering the raw data at a 20-Hz cutoff improved the accelerometer's relationship with MA data (mean bias 0.01 g; P > .05). When considering the data in 9 magnitude bands, the strongest relationship with the MA system was found in the 3.0-g or less band, and the precision of the accelerometer tended to reduce as the magnitude of impact acceleration increased. Of the 3 movements performed, the tackle-bag task displayed the greatest validity with MA. CONCLUSIONS: The findings indicate that the MinimaxX S4 accelerometer can accurately measure physical-collision peak impact accelerations when data are filtered at a 20-Hz cutoff frequency. As a result, accelerometers may be useful to measure physical collisions in contact sports.

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Nanofibres prepared by electrospinning have shown enormous potential for various applications. They are obtained predominantly in the form of nonwoven fibre webs. The 2-dimensional nonwoven feature and fragility have considerably confined their further processing into fabrics through knitting or weaving. Nanofibre yarns, which are nanofibre bundles with continuous length and a twist feature, show improved tensile strength, offering opportunities for making 3-dimensional fibrous materials with precisely controlled fibrous architecture, porous features and fabric dimensions. Despite a few techniques having been developed for electrospinning nanofibre yarns, they are chiefly based on the needle electrospinning technique, which often has low nanofibre productivity. In this study, we for the first time report a nanofibre yarn electrospinning technique which combines both needle and needleless electrospinning. A rotating intermediate ring collector was employed to directly collect freshly-electrospun nanofibres into a fibrous cone, which was further drawn and twisted into a nanofibre yarn. This novel system was able to produce high tenacity yarn (tensile strength 128.9 MPa and max strain 222.1%) at a production rate of 240 m h-1, with a twist level up to 4700 twists per metre. The effects of various parameters, e.g. position of the electrospinning units, operating conditions and polymer concentration, on nanofibre and yarn production were examined.

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The purpose of this investigation was to identify differences in end range of motion (ROM) kinetic and kinematic strategies between highly resistance and vertical jump-trained athletes and controls. Weightlifters (WL: n 4), short track speed skaters (STSS: n 5), and nonresistance-trained controls (C: n 6) performed 6 standing vertical squat jumps (SJ) and countermovement jumps (CMJ) without external resistance. Jump testing was performed using 3-dimensional marker trajectories captured with a 15-camera motion analysis system synchronized with 2 in-ground force plates. During SJ, there were large effects for the difference in time before toe off of peak vertical velocity between WL to STSS and C (ES: -1.43; ES: -1.73, respectively) and for the decrease between peak and toe off vertical velocity (ES: -1.28; ES: -1.71, respectively). During CMJ, there were large effects for the difference in time before toe off of peak vertical velocity between WL to STSS and C (ES: -1.28; ES: -1.53, respectively) and for decrease between peak and toe off vertical velocity (ES: -1.03; ES: -1.59, respectively). Accompanying these differences for both jump types were large effects for time of joint deceleration before toe off for all lower body joints between WL compared with C with large effects between WL and STSS at the hip and between STSS and C at the ankle. These findings suggest that the end ROM kinetic and kinematic strategy used during jumping is group-specific in power-trained athletes, with WL exhibiting superior strategies as compared with resistance- and jump-trained STSS.

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A fundamental premise in cloud computing is trying to provide a more sophisticated computing resource sharing capability. In order to provide better allocation, the Dominant Resource Fairness (DRF) approach has been developed to address the "fair resource allocation problem" at the application layer for multi-tenant cloud applications. Nevertheless conventional DRF only considers the interplay of CPU and memory, which may result in over allocation of resources to one tenant's application to the detriment of others. In this paper, we propose an improved DRF algorithm with 3-dimensional demand vector to support disk resources as the third dominant shared resource, enhancing fairer resource sharing. Our technique is integrated with LINUX 'group' controls resource utilisation and realises data isolation to avoid undesirable interactions between co-located tasks. Our method ensures all tenants receive system resources fairly, which improves overall utilisation and throughput as well as reducing traffic in an over-crowded system. We evaluate the performance of different types of workload using different algorithms and compare ours to the default algorithm. Results show an increase of 15% resource utilisation and a reduction of 59% completion time on average, indicating that our DRF algorithm provides a better, smoother, fairer high-performance resource allocation scheme for both continuous workloads and batch jobs.

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In this study, the photocatalytic decolorization and mineralization of Remazol Black B (RBB), an azo reactive dye, in aqueous solutions was investigated using UV/H2O2/ZnO, UV/H2O2/TiO2 and UV/H2O2/ZnO:TiO2 systems. ZnO and TiO2 nanoparticles were loaded on 3-dimensional polyethylene terephthalate fabrics (spacer fabrics). Morphology of the spacer fabrics and the presence of the nanoparticles were studied by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), respectively. Furthermore, the effects of key operational parameters on the efficiency of the decolorization were investigated. These parameters included initial pH value, initial hydrogen peroxide concentration, initial dye concentration, the loaded nanoparticle ratio and the presence of anions (sulfate, chloride and bicarbonate). Zero-, first- and second-order reaction kinetics were evaluated. Complete decolorization and high efficient mineralization with 90% total organic carbon (TOC) reduction were achieved at 120min treatment in the case of ZnO:TiO2 under optimum condition. The results proved that the novel heterogeneous photocatalytic process is capable of decolorizing and mineralizing azo reactive dyes in textile wastewater.

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 This thesis directly validated methods of estimating energetic gain and energetic expenditure in diving seals and sea lions. Results showed that head-mounted accelerometers and dive behaviour can predict foraging behaviour and energetic gain. In contrast, 3-dimensional body movement was unable to reliably predict energetic expenditure of diving pinnipeds.

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Bis(3-endo-camphoryl)phosphinic acid (1) was prepared by the reaction of the lithium enolate of D-(+)-camphor and phosphorous trichloride followed by an oxidative work up. Compound 1 crystallizes from wet toluene as monohydrate 1·H2O, which was investigated by X-ray crystallography. Molecules of 1 are associated by strong hydrogen bonds giving rise to the formation of a supramolecular helix. The interior channel of the helix is filled by a one-dimensional (1D) string of water molecules that are also associated by hydrogen bonding. The 1D string adopts a twisted zigzag conformation. Although the hydrogen bond networks are not cross-linked both the screw of the helix and the twist of the 1D string of water molecules are left-handed (M) and controlled by the chiral camphoryl residues situated on the exterior of the helix. The overall supramolecular structure is strongly reminiscent of aquaporin-1, a significant membrane-channel protein responsible for the transport of water into the cells.

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Microwave irradiation induces the 1,3-dipolar cycloaddition of cyclobutane epoxides with norbornenes to afford [n]polynorbornane scaffolds. Greatly enhanced reaction rates and significantly reduced levels of decomposition were observed.

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Surface-enhanced infrared absorption (SEIRA) spectra of manganese (III) tetraphenylporphine chloride (Mn(TPP)Cl) on metal island films were measured in transmission mode. Dependences of the enhancement factor of SEIRA on both the sample quantity and the type of evaporated metal were investigated by subsequently increasing the amount of Mn(TPP)Cl on gold and silver substrates. The enhancement increases nonlinearly with the amount of sample and varies slightly with the thickness of metal islands. In particular, the SEIRA transmission method presents an anomalous spectral enhancement by a factor of 579, with substantial spectral shifts, observed only for the physisorbed Mn(TPP)Cl that remained on a 3-nm-thick gold film after immersion of the substrates into acetone. A charge-transfer (CT) interaction between the porphyrinic Mn and gold islands is therefore proposed as an additional factor in the SEIRA mechanism of the porphyrin system. The number of remaining porphyrin molecules was estimated by calibration-based fluorescence spectroscopy to be 2.36×1013 molecules (i.e., ~2.910-11 mol/cm2) for a 3-nm-thick gold film, suggesting that the physisorbed molecules distributed very loosely on the metal island surface as a result of the weak van der Waals interactions. Fluorescence microscopy revealed the formation of microcrystalline porphyrin aggregates during the consecutive increase in sample solution. However, the immersion likely redistributed the porphyrin to be directly attached on the gold surface, as evidenced by an absence of porphyrinic microcrystals and the observed SEIRA enhancement. The distinctive red shift in the UV-visible spectra and the SEIRA-enhanced peaks indicate the presence of a preferred orientation in the form of the porphyrin ring inclined with respect to the gold surface.

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The engineering of soft functional materials based on the construction of three-dimensional interconnecting self-organized nanofiber networks is reported. The system under investigation is an organogel formed by N-lauroyl-L-glutamic acid di-n-butylamide (GP-1) in propylene glycol. The engineering of soft functional materials is implemented by controlling primary nucleation kinetics of GP-1, which can be achieved by both reducing thermodynamic driving force and/or introducing a tiny amount of specific copolymers (i.e., poly(methyl methacrylate comethacrylic acid)). The primary nucleation rate of GP-1 is correlated to the number density of GP-1 spherulites, which determines the overall rheological properties of soft functional materials. The results show that the presence of a tiny amount of the polymer (0.01-0.06%) can effectively inhibit the nucleation of GP-1 spherulites, which leads to the formation of integrated fiber networks. It follows that with the additive approach, the viscoelasticity of the soft functional material is significantly enhanced (i.e., more than 1.5 times at 40 °C). A combination of the thermal and additive approach led to an improvement of 3.5 times in the viscosity of the gel.

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 Cleavage factor IA (CF IA), cleavage and polyadenylation factor (CPF), constitute major protein complexes required for pre-mRNA 3' end formation in yeast. The Clp1 protein associates with Pcf11, Rna15 and Rna14 in CF IA but its functional role remained unclear. Clp1 carries an evolutionarily conserved P-loop motif that was previously shown to bind ATP. Interestingly, human and archaean Clp1 homologues, but not the yeast protein, carry 5' RNA kinase activity. We show that depletion of Clp1 in yeast promoted defective 3' end formation and RNA polymerase II termination; however, cells expressing Clp1 with mutant P-loops displayed only minor defects in gene expression. Similarly, purified and reconstituted mutant CF IA factors that interfered with ATP binding complemented CF IA depleted extracts in coupled in vitro transcription/3' end processing reactions. We found that Clp1 was required to assemble recombinant CF IA and that certain P-loop mutants failed to interact with the CF IA subunit Pcf11. In contrast, mutations in Clp1 enhanced binding to the 3' endonuclease Ysh1 that is a component of CPF. Our results support a structural role for the Clp1 P-loop motif. ATP binding by Clp1 likely contributes to CF IA formation and cross-factor interactions during the dynamic process of 3' end formation.

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 RNA polymerase II (RNAP II) transcription and pre-mRNA 3' end formation are linked through physical and functional interactions. We describe here a highly efficient yeast in vitro system that reproduces both transcription and 3' end formation in a single reaction. The system is based on simple whole-cell extracts that were supplemented with a hybrid Gal4-VP16 transcriptional activator and supercoiled plasmid DNA templates encoding G-less cassette reporters. We found that the coupling of transcription and processing in vitro enhanced pre-mRNA 3' end formation and reproduced requirements for poly(A) signals and polyadenylation factors. Unexpectedly, however, we show that in vitro transcripts lacked m⁷G-caps. Reconstitution experiments with CF IA factor assembled entirely from heterologous components suggested that the CTD interaction domain of the Pcf11 subunit was required for proper RNAP II termination but not 3' end formation. Moreover, we observed reduced termination activity associated with extracts prepared from cells carrying a mutation in the 5'-3' exonuclease Rat1 or following chemical inhibition of exonuclease activity. Thus, in vitro transcription coupled to pre-mRNA processing recapitulates hallmarks of poly(A)-dependent RNAP II termination. The in vitro transcription/processing system presented here should provide a useful tool to further define the role of factors involved in coupling.