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Vacuum gas atomization is the most commonly used technique to produce powders for additive manufacturing (AM). It is widely recognized that powder particle size distribution and micro-morphology can severely degrade the stability of powders in additive manufacturing and cannot be completely avoided. This particular study used a self-developed facility to produce aluminum powders that were sorted into various particle sizes via vacuum atomization. The study delved into the impact of melt superheat, positions of the delivery tube, and pressure on the physical properties of the powders. The findings indicated that pressure had the most pronounced effect on the satellite sphere. When the pressure was set at 3 MPa, the proportion of non-adherent powder reached 71.5%, with a span of 1.99. In contrast, the study revealed the influence of delivery tube position on the outcome was considerably negligible. [ABSTRACT FROM AUTHOR]

In this article we analyze the definition André proposed for near-vector spaces to make it more transparent. We also study the class of near-vector spaces over division rings and give a characterization of regularity that gives a new insight into the decomposition of near-vector spaces into regular subspaces. We explicitly describe span and deduce a new characterization of subspaces. [ABSTRACT FROM AUTHOR]

'The 1968 years' draw into memory the thoughts and images of other dates, protests, and political formations worldwide. The Naxalite movement of India was as different from the French May as was the Prague Spring from the Hungarian Uprising. Yet each gathered currents of ideas, energies, tactics – in brief, memories – from others and then released them into the world again. These are 'dates without places' which became possible after the Second World War, giving us to think not the excess of '68 but that which was in excess of '68: intertwined insurrectionary components, only some of which were 'local' while others were more mobile and remote. They reveal memory as a contagion of the imagination which must cease to be defined only in relation to the past, or to a place, and must instead be recognized as the faculty relating to the future. Memories of imagination do not commemorate particular events, places, or even forms like 'protest' and 'resistance.' They gather through the homologies and analogies perceived by the imagination. Homology obtains the memories of the powers of constructability in an object by transporting it materially into a new reality, while analogy maintains the memories of the partial powers of the abstractability of an object in imagination. May '68 and other dates without places harbour the memory of this imagination which opens new spans for things, their range of actualizable trajectories. Some of these memories have carried forward to the great recent protests – Occupy, Syntagma Square, the Arab Spring – but we live less and less in a time when the semblance of Elias Canetti's 'open crowds' can harbour imagination in politics. Our time would have to discover for itself the hidden spans of these twenty-first-century components, such that our memories of our own imagination remain actualizable. [ABSTRACT FROM AUTHOR]

This study was dealing with the spray drying of tailored mannitol particles as carriers in dry powder inhalation formulations. A self-constructed spray tower equipped with a laminar rotary atomizer was used to generate very narrow particle-size distributions. A design of experiments with rotation speed and drying temperature as factors was applied for the preparation of a broad set of different mannitol particles. Drying parameters affected particle properties like particle size, particle shape, surface roughness, and flowability significantly. Here, rotation speed was mainly affecting droplet and therefore particle size. Further, it was found that the inner particle temperature, and so the pressure inside the early particle shell, plays an important role during particle formation as emerging water vapor at higher temperatures served for indented particles and rough surface structures. Lower drying temperatures resulted in spherical and smooth particles as the inner temperature remained below the boiling temperature. The occurrence of these particle properties could further be related to mannitol carrier particle flow dynamics as large indented carriers were found to be less flowable than small spherical ones. In general, it was possible to control particle properties by the parameters of the spray drying process. [ABSTRACT FROM AUTHOR]

Estimation of vegetation covered soil moisture with satellite images is still a challenging task. Several models are available for soil moisture retrieval in which water cloud model (WCM) is most common. But, it requires an estimation of accurate vegetation parameterization. Thus, there is a need to develop such an approach for soil moisture retrieval which minimize these limitations. Therefore, this paper deals with the soil moisture retrieval using fully polarimetric SAR data by fusing the information from different bands. Various polarimetric indices and observables were critically analysed, and found that the index; SPAN (total scattered power) gives better information of vegetation cover as compared to other indices/observables. Based on this, WCM model has been modified using SPAN as parameter and soil moisture content were retrieved. [ABSTRACT FROM AUTHOR]

In this article we present a didactic proposal for teaching linear algebra based on two compatible theoretical models: emergent models and mathematical modelling. This proposal begins with a problematic situation related to the creation and use of secure passwords, which leads students toward the construction of the concepts of spanning set and span. The objective is to evaluate this didactic proposal by determining the level of match between the hypothetical learning trajectory (HLT) designed in this study with the actual learning trajectory in the second experimental cycle of an investigation design-based research more extensive. The results show a high level of match between the trajectories in more than half of the conjectures, which gives evidence that the HLT has supported, in many cases, the achievement of the learning objective, and that additionally mathematical modelling contributes to the construction of these linear algebra concepts. [ABSTRACT FROM AUTHOR]

We propose a novel parallel algorithm for generating all the sequences of binary reflectedGray codefor a given number of bits as input, targeting machines with multicore architectures. A theoretical analysis ofworkandspan, as well asparallelismof this algorithm, is carried out following a multithreaded implementation usingCilk++on a multicore machine. Theoretical analysis of this algorithm shows aparallelismof Θ(2n/log n) and achieves a linearspeedupon 12 cores for input data of sufficiently large size. [ABSTRACT FROM AUTHOR]

We propose a new method based on an algorithm usually dedicated to DNA sequence alignment in order to both reliably score short-term memory performance on immediate serial-recall tasks and analyse retention-error patterns. There can be considerable confusion on how performance on immediate serial list recall tasks is scored, especially when the to-be-remembered items are sampled with replacement. We discuss the utility of sequence-alignment algorithms to compare the stimuli to the participants' responses. The idea is that deletion, substitution, translocation, and insertion errors, which are typical in DNA, are also typical putative errors in short-term memory (respectively omission, confusion, permutation, and intrusion errors). We analyse four data sets in which alphanumeric lists included a few (or many) repetitions. After examining the method on two simple data sets, we show that sequence alignment offers 1) a compelling method for measuring capacity in terms of chunks when many regularities are introduced in the material (third data set) and 2) a reliable estimator of individual differences in short-term memory capacity. This study illustrates the difficulty of arriving at a good measure of short-term memory performance, and also attempts to characterise the primary factors underpinning remembering and forgetting. [ABSTRACT FROM PUBLISHER]

In order to prepare spherical salbutamol sulfate particles of adjustable size, a Nano Spray Dryer B-90 was employed. A 33full-factorial design was used to investigate the influence of process parameters (mesh size, feed concentration, and drying air temperature) on particle size (median size and width of the particle size distribution), amount of product produced per time, and product yield. The median particle size was significantly influenced by all three factors of the statistical design. Within the design space studied, particle sizes of 1.0 to 6.4 µm were obtained. The width of the particle size distribution (span) increased with increasing mesh sizes. All particles with a particle size greater than 2.4 µm showed a bimodal particle size distribution. Generally, larger mesh sizes as well as higher concentrations led to an increase in the amount of product prepared per time. The corresponding values observed were from 0.4 to 75.8 mg/min. The product yield was independent of the process parameters studied. All products were amorphous after spray drying and were stable up to a relative humidity of 60% at a temperature of 25°C. [ABSTRACT FROM AUTHOR]

In this paper we present an innovative instructional sequence for an introductory linear algebra course that supports students' reinvention of the concepts of span, linear dependence, and linear independence. Referred to as the Magic Carpet Ride sequence, the problems begin with an imaginary scenario that allows students to build rich imagery and formal definitions. The approach begins by focusing on vectors, their algebraic and geometric representations inand, and their properties as sets. Samples of student work are provided to illustrate the variety of student solutions and how these solutions lead to the creation of formal definitions. [ABSTRACT FROM PUBLISHER]

This paper presents a new approach to the modeling of congested traffic loading events on long span bridges. Conventional traffic load models are based on weigh-in-motion data of non-congested traffic, or something similar to a Poisson Arrival process. In neither case do they account for the mixing between lanes that takes place as traffic becomes congested. It is shown here that cars move out from between trucks as traffic slows down which results in a higher frequency of long platoons of trucks in the slow lane of the bridge. These longer platoons increase some characteristic load effects under the slow lane by a modest but significant amount. Micro-simulation, the process of modeling individual vehicles that is widely used in traffic modeling, is presented here as a means of predicting imposed traffic loading on long-span bridges more accurately. The traffic flow on a congested bridge is modelled using a random mixing process for trucks and cars in each lane, where each vehicle is modelled individually with driver behaviour parameters assigned randomly in a Monte Carlo process. Over a number of simulated kilometres, the vehicles move between lanes in simulated lane-changing manoeuvres. The algorithm was calibrated against video recordings of traffic on a bridge in the Netherlands. Extreme value statistics of measured strains on the bridge are then compared to the corresponding simulation statistics to validate the model. The micro-simulation algorithm shows that the histograms of truck platoon length are moderately affected by lane changing. This in turn is shown to influence some characteristic load effects of the bridge deck. [ABSTRACT FROM PUBLISHER]

In this article, double emulsion method was used to prepare solid lipid nanoparticles (SLN). Different kinds of SLN were synthesized by changing the species and contents of lipids and surfactants in microemulsion. The effects of the hydrophobic chain length of surfactant inside and surfactant outside, the type of lipid and the ratio of Span/Tween on SLN were systematically investigated. Dynamic light scattering (DLS) and zeta potential were applied to study the change trend of particle size and surface charge of SLN. The DLS results show that the size of SLN increases as the hydrophobic chain length of lipid enhances, and decreases with the increase of hydrophobic chain length of Tween or that of Span or the ratio of Span/Tween. And the absolute value of zeta potential as well as the stability of SLN dispersion decreases as the hydrophobic chain length of Span or lipid increases, and increases when the hydrophobic chain length of Tween or the ratio of Span/Tween increases. [ABSTRACT FROM AUTHOR]

Congenital amusia is a disorder that affects the perception and production of music. While amusia has been associated with deficits in pitch discrimination, several reports suggest that memory deficits also play a role. The present study investigated short-term memory span for pitch-based and verbal information in 14 individuals with amusia and matched controls. Analogous adaptive-tracking procedures were used to generate tone and digit spans using stimuli that exceeded psychophysically measured pitch perception thresholds. Individuals with amusia had significantly smaller tone spans, whereas their digits spans were a similar size to those of controls. An automated operation span task was used to determine working memory capacity. Working memory deficits were seen in only a small subgroup of individuals with amusia. These findings support the existence of a pitch-specific component within short-term memory and suggest that congenital amusia is more than a disorder of fine-grained pitch discrimination. [ABSTRACT FROM AUTHOR]

In spite of a large body of empirical research demonstrating the importance of multisensory integration in cognition, there is still little research about multimodal encoding and maintenance effects in working memory. In this study we investigated multimodal encoding in working memory by means of an immediate serial recall task with different modality and format conditions. In a first non-verbal condition participants were presented with sequences of non-verbal inputs representing familiar (concrete) objects, either in visual, auditory or audio-visual formats. In a second verbal condition participants were presented with written, spoken, or bimodally presented words denoting the same objects represented by pictures or sounds in the non-verbal condition. The effects of articulatory suppression were assessed in both conditions. We found a bimodal superiority effect on memory span with non-verbal material, and a larger span with auditory (or bimodal) versus visual presentation with verbal material, with a significant effect of articulatory suppression in the two conditions. [ABSTRACT FROM AUTHOR]

The molecular compositions of the commercial nonionic surfactants Span 80 and Span 85 were analyzed by reversed phase high performance liquid chromatography (HPLC). Both surfactants are mixtures of fatty acid esters, containing monoesters, diesters, triesters, and tetraesters. While diesters dominate in the case of Span 80, Span 85 contains mainly tetraesters. Vesicles were prepared from Span 80 (or Span 85) by a two‐step emulsification method that involved homogenization and separation steps in which a portion of the surfactants was removed. The composition of the vesicles was analyzed by HPLC with respect to the different esters present. Although commercial Span 80 and Span 85 differ considerably in their molecular compositions, the ester profiles of the vesicles formed were in both cases rather similar and dominated by diesters. Therefore, the particular vesicle preparation method leads to a molecular selection of mainly those components that are prone to form bilayers. [ABSTRACT FROM AUTHOR]