Virtual Ensemble Research Articles

Understanding virtual rehearsal participation through self-determination theory

ABSTRACT The motivation to participate in ensemble rehearsals may be influenced by the rehearsal environment. With the emergence of the virtual rehearsal environment, there is a need to gain a better understanding of how online rehearsals affect participation decisions. The purpose of this study was to determine the applicability of one theory of motivation, Self-Determination Theory, to older adults’ decisions to participate or not participate in virtual rehearsals. Respondents (N = 49) included participants (n = 20) and nonparticipants (n = 29) who completed the Intrinsic Motivation Inventory (n.d.) and the Modified Computer Self-Efficacy Scale (Laver et al. 2012). Mann–Whitney U comparisons indicated that nonparticipants had significantly lower ratings on the Perceived Competence and Value/Usefulness subscales on the IMI, in addition to significantly lower feelings of self-efficacy on the MCSES. Overall, the results seem to support the use of Self-Determination Theory to explain differences in the decision of New Horizons band members to participate in online rehearsals. To encourage participation in virtual ensembles, there is need to confirm ensemble members are comfortable with the technology and understand the value and usefulness of the activity itself.

Metabolic activity diffusion imaging (MADI): I. Metabolic, cytometric modeling and simulations.

Evidence mounts that the steady-state cellular water efflux (unidirectional) first-order rate constant (kio [s-1 ]) magnitude reflects the ongoing, cellular metabolic rate of the cytolemmal Na+ , K+ -ATPase (NKA), c MRNKA (pmol [ATP consumed by NKA]/s/cell), perhaps biology's most vital enzyme. Optimal 1 H2 O MR kio determinations require paramagnetic contrast agents (CAs) in model systems. However, results suggest that the homeostatic metabolic kio biomarker magnitude in vivo is often too large to be reached with allowable or possible CA living tissue distributions. Thus, we seek a noninvasive (CA-free) method to determine kio in vivo. Because membrane water permeability has long been considered important in tissue water diffusion, we turn to the well-known diffusion-weighted MRI (DWI) modality. To analyze the diffusion tensor magnitude, we use a parsimoniously primitive model featuring Monte Carlo simulations of water diffusion in virtual ensembles comprising water-filled and -immersed randomly sized/shaped contracted Voronoi cells. We find this requires two additional, cytometric properties: the mean cell volume (V [pL]) and the cell number density (ρ [cells/μL]), important biomarkers in their own right. We call this approach metabolic activity diffusion imaging (MADI). We simulate water molecule displacements and transverse MR signal decays covering the entirety of b-space from pure water (ρ = V = 0; kio undefined; diffusion coefficient, D0 ) to zero diffusion. The MADI model confirms that, in compartmented spaces with semipermeable boundaries, diffusion cannot be described as Gaussian: the nanoscopic D (Dn ) is diffusion time-dependent, a manifestation of the "diffusion dispersion". When the "well-mixed" (steady-state) condition is reached, diffusion becomes limited, mainly by the probabilities of (1) encountering (ρ, V), and (2) permeating (kio ) cytoplasmic membranes, and less so by Dn magnitudes. Importantly, for spaces with large area/volume (A/V; claustrophobia) ratios, this can happen in less than a millisecond. The model matches literature experimental data well, with implications for DWI interpretations.

“Modal Preludes and Fugues in C” by Borislava Stronko: Specific Use of Modal Technology

The relevance of the article. The most pressing need today is to turn to modern samples of polyphonic music, which is due, on the one hand, to artistic practice, and on the other, to rethinking traditional polyphonic forms and techniques in the context of a total experiment and a radical renewal of musical techniques. B. Stronko’s “Modal Preludes and Fugues in C” demonstrate a completely new, author’s version of the interpretation of the polyphonic cycle, which is due to the non-traditional combination of modality with polyphonic principles and methods of development. The change in the functionally centralized fret-tonal system to a radically different, modal, type of modal organization caused significant changes at all tiers of the multilevel organization of the fugue, starting from its core — the theme, ending with the principles of composition and shaping. To trace exactly what specific changes that were caused by the use of modal technique in the framework of the fugue and is the central problem of the study and determines its relevance
 Scientific novelty: for the first time, all the preludes and fugues of the cycle “Modal preludes and fugues in C” were thoroughly analyzed with an emphasis on the study of the “semantic source” of the polyphonic cycle (fugue), its quintessence (theme) in terms of the influence of the principles of modality on the construction of the fugue.The purpose of the article: to identify the features of the use of modal technique and the specificity of its influence on various structural levels of the fugue in the cycle “Modal preludes and fugues in C” by Boryslav Stronkо, as well as to determine the special features of the composer’s polyphonic thinking.
 The research methodology includes the use of systemic and functional methods.
 Main results and conclusions. All fugues from the cycle «Modal Preludes and Fugues in C» by B. Stronko represent an open cycle based on the modal principle of organization. The cycle itself is potentially open and represents the composer’s desire to achieve freedom and emphasize the potential for infinity of the process of creating modes. Each pair of preludes and fugues is limited by a scale of a certain design, which made it possible to create compositions with a pronounced individual flavor.
 At the level of thematicism: compactness of themes and fugues themselves, intonation specificity, depending on the structure of the fret. With further themes, linearity of development prevails, the composer uses the principle of multivariate repetition (isomelia, isorhythmy, interpolation, combinatorics), which has a certain relationship with rehearsal technique and becomes a specific feature of Boryslav Stronko’s polyphonic thinking. Multivariate repetition of the material, despite the actual changes, enhances the fading effect, being in one place and organically combines with the idea of being in the conditions of one specific sound of the chosen fret.
 Attention is drawn to the technique of replicating rhythmic-intonational structures — it is a quasi-sequential repetition of a motive in one or several voices at the same time, most often it variably changes in all voices, repeating with a horizontal shift or with the simultaneous use of various techniques (isorhythmy, isomelia, combinatorics). The role of ostinato increases significantly, which, together with the above techniques, contributes to the creation of the effect of hidden internal movement while actually staying in one place. It should be noted that all the above principles, which create the effect of a specific sound and work on the idea of constant rotation in a single sound space, turn out to be stable not only for “Modal preludes and fugues in C”, but also for other works of the composer: “Labyrinth Chord”, 4-part symphony for virtual ensemble (2016), “Time Crystals” (or “Metavariations for metapiano”) is an electronic music cycle (2018).

Creating Virtual Ensembles: Common Approaches from Research and Practice

A virtual ensemble is a digital musical product that uses multiple recordings edited together to form a musical ensemble. Creating virtual ensembles can be a way for music educators to engage students through online music-making. This article presents eight steps for creating virtual ensembles in music education courses and classrooms. The steps are (1) identifying objectives and desired outcomes, (2) selecting repertoire, (3) developing learning resources, (4) creating an anchor for synchronizing, (5) choosing a recording method, (6) setting up a collection platform, (7) editing in postproduction, and (8) distributing the product. As online music production becomes more prevalent, projects like virtual ensembles can provide creative and exciting experiences for music teachers and students, whether produced in the classroom or through remote means on the Internet.

Connecting music education and virtual performance practices from YouTube

ABSTRACTThe Internet has inspired musicians to explore technologies to produce recorded music performances. Social media sites like YouTube provide spaces for musicians to share their works, and the advances of technologies that afford venues and opportunities for performers to share their crafts. As amateur Internet musicians develop practices to create and produce performances, educators may benefit by understanding their processes so that music making practices from outside of the classroom can be incorporated into formal educational settings. This case study explores how David Wesley François, a virtual ensemble creator who published arrangements on YouTube, acquired the skills needed to become a productive virtual performer. A narrative describes François's formal music education, which was supplemented by informal music and technological learning. By exploring cases such as this, educators may be able to translate virtual performance practices to the classroom, thus preparing students to create digital music within the classroom and beyond.

Impact of distributions on the archetypes and prototypes in heterogeneous nanoparticle ensembles.

The magnitude and complexity of the structural and functional data available on nanomaterials requires data analytics, statistical analysis and information technology to drive discovery. We demonstrate that multivariate statistical analysis can recognise the sets of truly significant nanostructures and their most relevant properties in heterogeneous ensembles with different probability distributions. The prototypical and archetypal nanostructures of five virtual ensembles of Si quantum dots (SiQDs) with Boltzmann, frequency, normal, Poisson and random distributions are identified using clustering and archetypal analysis, where we find that their diversity is defined by size and shape, regardless of the type of distribution. At the complex hull of the SiQD ensembles, simple configuration archetypes can efficiently describe a large number of SiQDs, whereas more complex shapes are needed to represent the average ordering of the ensembles. This approach provides a route towards the characterisation of computationally intractable virtual nanomaterial spaces, which can convert big data into smart data, and significantly reduce the workload to simulate experimentally relevant virtual samples.

From tacit to verbalized knowledge. Towards a culturally informed musical analysis of Central Javanese karawitan

In the music cultures of the world we encounter both tacit and verbalized musical knowledge to various degrees. In order to reconstruct emic views on musical concepts and practices which are a prerequisite of any seriously culturally informed musical analysis we need to disclose local knowledge by appropriate means even if it is not directly open to verbal discourse. Current computer technology enables us to set up interactive experiments where local experts can verbally address relevant musical features in discussing audio examples which have been prepared by the researcher. The performance of virtual musicians can be evaluated by the local experts and various relevant parameters may be investigated individually if suitable versions of customary pieces are available. Thus aspects which seem to be tacit knowledge because they usually elude verbal discourse can be made accessible and transformed into verbalized, declarative knowledge. The paper presents preliminary results of a case study on Central Javanese gamelan music (karawitan) where renowned Javanese musicians commented on computer-generated versions of traditional compositions regarding the idiomatically appropriate performance practice of the virtual ensemble as well as the tuning and sound of various virtual gamelan sets emulated by the computer.

Participatory culture and informal music learning through video creation in the curriculum

Abstract With the emergence of YouTube, social media and video creation technologies, music education can expand its scope to include video-based music creation. This multimodal study examines how undergraduate music education students created music videos during an informal music learning project in an introduction to music education and technology course at a large, Midwestern, public university. Data were collected in three modes: observation of students’ music video projects, a web survey including both quantitative and qualitative questions, and student interviews. Excerpts from the projects were shown during class and students were encouraged to share their videos with others on the Internet thus developing a community in the classroom that expanded through social media. Overall, students reacted positively to creating music videos as part of the curriculum. The projects led to a self-reported sense of accomplishment and satisfaction for almost all of the respondents. Because the students were given the opportunity to create music videos on their own terms, a diversity of video types emerged: covers, instrumental explorations, activism and awareness videos, musical artistic statements and virtual ensemble arrangements. The respondents used a variety of hardware and software, approaches to recording and musical genres. The informal music learning practice of ‘dropping students in the deep end’ proved to be initially intimidating, but ultimately freeing.

The Effects of Theta Precession on Spatial Learning and Simplicial Complex Dynamics in a Topological Model of the Hippocampal Spatial Map

Learning arises through the activity of large ensembles of cells, yet most of the data neuroscientists accumulate is at the level of individual neurons; we need models that can bridge this gap. We have taken spatial learning as our starting point, computationally modeling the activity of place cells using methods derived from algebraic topology, especially persistent homology. We previously showed that ensembles of hundreds of place cells could accurately encode topological information about different environments (“learn” the space) within certain values of place cell firing rate, place field size, and cell population; we called this parameter space the learning region. Here we advance the model both technically and conceptually. To make the model more physiological, we explored the effects of theta precession on spatial learning in our virtual ensembles. Theta precession, which is believed to influence learning and memory, did in fact enhance learning in our model, increasing both speed and the size of the learning region. Interestingly, theta precession also increased the number of spurious loops during simplicial complex formation. We next explored how downstream readout neurons might define co-firing by grouping together cells within different windows of time and thereby capturing different degrees of temporal overlap between spike trains. Our model's optimum coactivity window correlates well with experimental data, ranging from ∼150–200 msec. We further studied the relationship between learning time, window width, and theta precession. Our results validate our topological model for spatial learning and open new avenues for connecting data at the level of individual neurons to behavioral outcomes at the neuronal ensemble level. Finally, we analyzed the dynamics of simplicial complex formation and loop transience to propose that the simplicial complex provides a useful working description of the spatial learning process.

Wireless Virtual Multiple Antenna Networks for Critical Process Control: Protocol Design and Experiments

Wireless telemetry systems for remote monitoring and control of industrial processes are now becoming a relevant topic in the field of networked control. Wireless closed-loop control systems have stricter delay and link reliability requirements compared to conventional sensor networks for open-loop monitoring and call for the development of advanced network architectures. By following the guidelines introduced by recent standardization, this paper focuses on the most recent technological advances to enable wireless networked control for tight closed-loop applications with cycle times below 100 ms. The cooperative network paradigm is indicated as the key technology to enable cable replacing even in critical control applications. A cooperative communication system enables wireless devices placed at geographically separated locations to act as a virtual ensemble of antennas that creates a virtual multiple-antenna-distributed system. A proprietary link-layer protocol/based on the IEEE 802.15.4 physical layer has been developed and tested in an indoor environment characterized by non-line-of-sight (NLOS) propagation and dense obstacles. The measurements obtained from the testbed evaluate experimentally the benefits (and the limitations) of cable replacing in critical process control.

Human movement expressivity for mobile active music listening

In this paper we describe the SAME networked platform for context-aware, experience-centric mobile music applications, and we present an implementation of the SAME active music listening paradigm: the Mobile Conductor. It allows the user to express herself in conducting a virtual ensemble playing a MIDI piece of music by means of her mobile phone. The mobile phone detects the user’s hand movement and molds the music performance style by modulating its speed, volume, and intonation.

Communities of sound: Examining meaningful engagement with generative music making and virtual ensembles

In this article, we examine the affordances of the concept of network jamming as a means of facilitating social and cultural interaction, that provides a basis for unified communities that use sound and visual media as their key expressive medium. This article focuses upon the development of a means of measuring social and musical benefit through correlation with meaningful engagement and provides examples of inclusive ensembles, and the specification of musical knowledge through algorithmic and educational experience design. This research builds on the design and development of the jam2jam family of generative software and hardware applications. An emerging theoretical model for observing meaningful engagement in community music making is examined against three case studies selected from a larger scale long-termed research project. In this analysis of case studies we specifically employ an observational tool called the meaningful engagement matrix, discuss its development and describe how it functions to feed back data which informs software development, theories of social engagement and experience design.

Jam2jam

Jam2jam

Hybrid Classification for Face Recognition with Virtual Samples and Ensemble Neural Networks

Abstract This paper presents a novel hybrid classifier with artificially generated virtual training samples for face recognition. Our approach obtains a synergy effect by combining the results of two heterogeneous classifiers, and utilizes the nearest neighbor approach in feature angle space and a connectionist model. The first is a classifier called the nearest feature angle (NFA) based on angular information, which finds the most similar to the query from a given training set. The second is a classifier based on the recall of stored frontal projection of input features using a frontal recall network (FRN) that finds the most similar frontal one among the stored frontal feature set. For FRN, we used an ensemble neural network consisting of multiple MultiLayer Perceptrons (MLPs), each of which is trained independently to enhance generalization capability. Further, both classifiers used a virtual training set generated adaptively according to the spatial distribution of each person’s training samples. Fina...

Comparison of a single-model EPS with a multi-model ensemble consisting of a few operational models

Since the introduction of operational ensemble forecasts in Numerical Weather Prediction(NWP) more than 5 years ago, the dispute on how to best determine the initial perturbationshas largely dominated the direction of research in the field of ensemble prediction. While it isimportant to consider uncertainties in the initial condition, errors due to model physics or themodel numerics and truncation provide another source of forecast errors and might also beconsidered in ensemble prediction. In this study, we compare the performance of 2 fundamentallydifferent ensemble schemes. First, the ensemble prediction system (EPS) of the European Centrefor Medium Range Forecasts is taken as a representative of the single-model approach basedon the perfect model assumption and thus taking only the uncertainty in the observations intoaccount. Second, a virtual ensemble comprised of the operational forecasts of 4 NWP centersas a “gratis” candidate of the multi-model approach which, in addition, takes model errors intoaccount. The comparison is based on forecasts of 500 hPa fields over Europe for a summer anda winter period in 1997 and on diagnostics ranging from various measures for the performanceof the ensemble means to the statistical consistency and discrimination properties of theensembles. The different sizes of both ensembles poses the main difficulty for the interpretationof the results. If the ensemble size is not considered as a criterion for the evaluation, the resultslead to controversial conclusions; but when penalizing for an overly large and inefficientensemble the results are for the most part consistent, and one has to conclude that the multimodelensemble performs better in most forecast aspects.

On the study of the mass ratio of spectroscopic binaries

We present a new algorithm to derive the true mass-ratio distribution of an observed sample of spectroscopic binaries. The algorithm includes an iterative procedure in which each binary of unknown inclination is replaced by an ensemble of virtual systems with a distribution of inclinations. This work shows that contrary to a widely held assumption, the inclination angles of each virtual ensemble should not be distributed randomly in space. We also suggest a way to account for the observational selection effect associated with the inability to detect single-line spectroscopic binaries with low-amplitude radial-velocity modulation

The Mass–Ratio Distribution of Short–Period Binaries

Abstract We present a new algorithm to derive the mass-ratio distribution of an observed sample of spectroscopic binaries. The algorithm replaces each binary of unknown inclination by an ensemble of virtual systems with a distribution of inclinations. We show that contrary to a widely held assumption the orientations of each virtual ensemble should not be distributed randomly in space. A few iterations are needed to find the true mass-ratio distribution. Numerical simulations clearly demonstrate the advantage of the new algorithm over the classical method. We have applied the new algorithm to the recent large sample of G-dwarf spectroscopic binaries, and got a uniform or perhaps a slightly rising linear mass-ratio distribution. This result suggests that the mass-ratio distributions of short-period and long-period binaries are substantially different. It also indicates that the mass distribution of the secondary stars is not the same as that of the single stars.

Statistical Weights for Primary Structures of Inhomogeneous Polymer Chains

AbstractWe analyze the distribution of configurational averages over an ensemble of primary structures. These primary structures are given by base sequences for linear polymers of fixed length N constructed randomly from two different kinds of monomers. The variance V(R2) of the thermally averaged square size of the random coil is calculated by defining a virtual ensemble of homogeneous polymers of length N. This ensemble is determined by effective short range two and three body interactions. We prove that V(R2) increases with the information content given by the length N. Specially, V(R2) ∼ N2.