Journal articles on the topic 'Sparse VAR Modelling'

Advances in digital technology have raised the capacity of capturing, processing and analyzing spatial data, bringing realistic and accurate reproductions of the elements in archaeological spaces. Current hardware and software have great potential in modelling phenomena and simulating their parameters, leading effective resources to these archaeological issues that have been hard to tackle until recent dates (intrusive techniques, heritage risk, hidden places, unavoidable impediments…). Thus, to approach contextual implications, we propose lighting simulation in aphotic sites as a procedure to study spatial relations between social agents and elements. In this paper we relate the necessary light intensity, its spatial distribution, and any derived implications for activity performing, especially in rock art production and visualization.

The Portes Mordelaises, remnants of the medieval city walls of Rennes, France, has been the subject of several archaeological excavations until 2017. From these excavations, we created a three-dimensional (3D) model of the site reconstructed as it would have appeared during the 15th century, including the surrounding plus the interiors of its famed towers. Once our efforts and results were officially recognised as being of national interest by the French Ministry of Culture and Communication, Department of Heritage and the National Museum Service of France, we presented our virtual model reconstruction in an exhibition curated by the Museum of Bretagne, entitled "Rennes, les vies d'une ville" (Rennes, the Lives of a City). This approach to 3D reconstruction of the site served to further study Rennes’ origins, its construction, organisation, as well as its historic relationship to surrounding territories. The main objective of this work was to investigate, using of a significant and complex archaeological site as proof of concept, how the digitalisation of an existing structure, the modelling of its hypothetical structures, and the interactions with its virtual spaces enabled the general public to provide critical feedback, and enhance archaeological knowledge and evaluation of such sites. This reconstruction was carried out under a West Digital Conservatory of Archaeological Heritage project, whose mission is to support and advise archaeologists in the production and exploration of 3D archaeological datasets using the latest digitisation, modelling, and virtual reality (VR) techniques. Through a complex but repeatable process, using the valuable data provided by various excavations, in addition to new information provided by the 3D digitalisation itself, we produced a 3D model, fully satisfactory to rigorous scientific standards, which was then incorporated into a VR space ready for diffusion to the general public. Furthermore, the fact that 45850 visitors were welcome to experience our 3D model at an exhibition in a city the size of Rennes proved to be a significant success.

Highlights: A virtual 3D model of a botanical garden was built based on a GIS with plants botanical information and buildings, statues and other assets historical information. The height and crown diameter of individual trees were determined from watershed operations on aerial LiDAR data. Statues were modelled photogrammetrically. Buildings were modelled procedurally using CGA rules. Users found realism and information access to be the most positive points. The way of data organisation and the elaborated modelling rules make the product easily extendable for new data and objects. Abstract: Botanical gardens are important spots in urban spaces, both for researchers and for many different kinds of public. Conveying scientific information by means of an attractive digital product, on a pre- or post-visit experience, is a way of captivating the public, especially the younger generation, to the relevance of those gardens as repositories of knowledge and for conservation of plant species diversity. This approach also facilitates communication with the general public and access to historical data. On the other hand, bringing the garden to the desktop of researchers and managers can be an advantage, not only for an overview of the status quo but also in spatial planning matters. This paper describes the production of a 3D dynamic model of the Tropical Botanical Garden in Lisbon on top of a Geographic Information System (GIS). Its development included creating a spatial database to organise data originating from a variety of sources, the three-dimensional (3D) modelling of plants, buildings and statues, the creation of web pages with historic and contextual information, as well as the publication of a number of interactive 3D scenes. Several software packages were used, and the final outputs were published in ArcGIS Online to be explored by the public and researchers (link provided at the end of the text). The data are organised in a database, and most 3D modelling tasks are procedural through Computer Generated Architecture (CGA) rules. Thus, updating information or 3D models can be done without having to repeat all steps, an important feature for a dynamic botanical garden. Challenges and solutions are also addressed, providing a constructive contribution to the further implementation of similar experiences in other botanical gardens. According to a user survey carried out, the realism of the representation and the possibility of easily retrieving information from the objects are the most positive aspects of the project.

This paper describes the case study of the damaged church of St. Francesco in the hamlet of Arquata del Tronto (Italy) that was struck by the earthquake in 2016. The municipality commissioned the research to support the preliminary design of the preservation plan. The first digitisation level has been started from the richness of surveying data acquired from static and dynamic terrestrial laser scanning (TLS), and photogrammetry, overcoming challenging constraints due to the scaffolding covering the surfaces. The geometric survey allowed authors to acquire massively geometric and material information supporting the three-dimensional (3D) volume stratigraphic and the creation of the Heritage Building Information Modelling (HBIM). The paper proposes a shift from the Geographic Information System (GIS)-based analysis of the materials toward spatial HBIM management. Building Archaeology is turned into HBIM 3D volume stratigraphy, overcoming the bidimensional (2D) surface mapping, in favour of a 3D understanding of direct and indirect sources. Material mapping is added to HBIM 3D volume stratigraphy, and each stratigraphic unit (SU) has its proprieties. The 3D volume stratigraphic database has been designed to collect the data on the unit detection at three levels (direct sources data collection, indirect data documentation, the relation among the BIM object elements). A common data environment (CDE) has been set up to share the 3D volume informative models that can be accessed, and all the information gathered. The knowledge transfer using the eXtended reality (XR) has been devoted to the citizen and tourist fruition, enhancing the comprehension of difficult concepts like the SUs to support a better critical 3D reconstruction. It includes the phases of construction across time-lapse documentation that validates related information within the building archaeology informative models leaving spaces to the uncertainty and documenting the relationship established so far thanks to the direct and indirect sources. The result obtained is a live digital twin that can be continuously updated, which justifies the costs and time demanding of HBIM despite 2D drawings.Highlights: • 3D survey and scan-to-HBIM process for the creation of a digital twin were oriented to the preliminary design of the preservation plan of the church of St. Francesco in Arquata del Tronto (Italy). • Stratigraphy is investigated and oriented towards a digitisation process to share different levels of knowledge through new forms of digital-sharing such as Common Data Environment (CDE) and cloud-based BIM platform. • eXtended reality (XR) is the final tool to reach new levels of communication and a wider audience characterised by experts in the construction sector and virtual and non-expert tourists.

Flaviviruses are assembled to bud into the lumen of the endoplasmic reticulum (ER) and are secreted through the vesicle transport pathway, but the details of the molecular mechanism of virion assembly remain largely unknown. In this study, a highly conserved region in the prM protein was identified among flaviviruses. In the subviral particle (SP) system of tick-borne encephalitis virus (TBEV) and Japanese encephalitis virus, secretion of SPs was impaired by a mutation in the conserved region in the prM protein. Viral proteins were sparse in the Golgi complex and accumulated in the ER. Ultrastructural analysis revealed that long filamentous structures, rather than spherical SPs, were observed in the lumen of the ER as a result of the mutation. The production of infectious virions derived from infectious cDNA of TBEV was also reduced by mutations in the conserved region. Molecular modelling analysis suggested that the conserved region is important for the association of prM–envelope protein heterodimers in the formation of a spike of immature virion. These results are the first demonstration that the conserved region in the prM protein is a molecular determinant for the flavivirus assembly process.

The virtual reconstruction of ancient architecture aims at describing the ‘original’ elevation and volume of a disappeared building. The feeble archaeological traces, often limited to their foundations, left by houses impair the reinstating of their image, in contrast to that which is made possible by the massive structures of public buildings. A twofold problem arises when dealing with timber structures during a reconstruction procedure: at the local scale of the individual beam (e.g. joists or rafters), one must define a beam’s cross-section given its span; at the overall scale, the shape of a building results from that which its structures allowed it to have been. Therefore, this work proposes a procedure to deal with the ‘local’ problem, i.e. the definition of a beam’s cross-section from its span. To that end, a simplified, parametric structural model is required. The available bits of information are organized into inputs, parameters and outputs of the analytical problem by matching each information with a structural quantity (load, cross-section, spacing, etc.). Two mathematical relationships among them are proposed, which express two equally possible dimensioning criteria, based either on joists’ strength or deformability. It seems that the joist’s strength was the option for lightly loaded joists, as in roofs or tightly spaced floor frames; conversely, heavily loaded joists conformed to the deformability criterion. Both dimensioning procedures are translated into a visual algorithm in Grasshopper, a plugin for Rhinoceros modelling software, which enables the parametric definition of objects. Finally, the proposed procedure is tentatively applied to automatically reconstruct the floor and roof frames that belonged to the domus on top of the Sarno Baths in Pompeii. The algorithm automatically picked the dimensioning criterion in relation to each frame’s span and hypothesized loads and determined joists’ orientation and minimum cross-sections. The obtained floor frames, whose structural conditions are considered as sensible, will be adopted in the overall virtual reconstruction proposal of the ruins, also based on the analytical evaluation of masonry structures.Highlights:- Proposal of a structural model for the dimensioning of timber floor beams in domestic spaces based on archaeological and literature information.- Parametrical interpretation of the model in Grasshopper for Rhinoceros software and optimization analysis of the structural parameters involved.- Application of the model to the reconstruction of floor frames in a house in the Sarno Baths complex, Pompeii.

In this paper, we consider the compressible Navier–Stokes equation with density-dependent viscosity coefficients and a term of capillarity introduced formally by van der Waals in Ref. 51. This model includes at the same time the barotropic Navier–Stokes equations with variable viscosity coefficients, shallow-water system and the model introduced by Rohde in Ref. 46. We first study the well-posedness of the model in critical regularity spaces with respect to the scaling of the associated equations. In a functional setting as close as possible to the physical energy spaces, we prove global existence of solutions close to a stable equilibrium, and local in time existence of solutions with general initial data. Uniqueness is also obtained.

Abstract. Soil moisture is a key parameter for land surface water resource and climate change monitoring. ESA's Soil Moisture and Ocean Salinity (SMOS) mission will deliver, as one of its main goals, global fields of surface soil moisture with an accuracy better than 0.04 m3 m−3. SMOS relies on an L-band (1.4 GHz) interferometric radiometer. Within the context of the preparation for this mission over land, the Valencia Anchor Station (VAS) experimental site, in Spain, was selected to be one of the main test sites in Europe for the SMOS Calibration/Validation (Cal/Val) activities. This study presents preliminary analysis of PERSIANN in the framework of SMOS Cal/Val activities at the Valencia Anchor Station. The PERSIANN database is an automated system for Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks. The real interest of using the PERSIANN database into the hydrologic applications is mainly with the goal of having access to the spatial and temporal distribution of precipitation over a significant area (typically here an area equivalent to a SMOS pixel). The goal of this study is to quantify the gain of using PERSIANN instead of distributing sparse rain gauge measurements. The interest of using satellite rainfall estimates as well as the influence that the precipitation events can induce on the modelling of the water content in the soil was depicted by a comparison between different soil moisture products. Having an accurate estimation of the amount and temporal/spatial distribution of precipitation is a critical issue so as to have a faithful representation of the soil moisture distribution.

ABSTRACT The excursions of star clusters and galaxies around statistical equilibria are studied. For a stable ergodic model Antonov’s Hermitian operator on six-dimensional phase space has the normal modes as its eigenfunctions. The excitation energy of the system is just the sum of the (positive) energies associated with each normal mode. Formulae are given for the DFs of modes, which are of the type first described by van Kampen rather than Landau, and Landau ‘modes’ can be expressed as sums of van Kampen modes. Each van Kampen mode comprises the response of non-resonant stars to driving by the gravitational field of stars on a group of resonant tori, so its structure is sensitive to the degree of self gravity. The emergence of global distortions in N-body models when particles are started from an analytical equilibrium is explained in terms of the interplay of normal modes. The positivity of modal energies opens the way to modelling the thermal properties of clusters in close analogy with those of crystals.

Light Detection and Ranging (LiDAR) has become an important data source in urban modelling. Traditional methods of LiDAR data processing for building detection require high spatial resolution data and sophisticated algorithms. The aerial photos, on the other hand, provide continuous spectral information on buildings. However, the accuracy of classified building boundaries from aerial photos is constrained when building roofs and their surroundings share analogous spectral characteristics. This paper develops a statistical approach that can integrate characteristic variables derived from sparse LiDAR points and air photos to detect buildings by estimating object heights and identifying clusters of similar heights. Within this study, the approach chooses a local regression method, namely geographically-weighted regression (GWR), to account for local variations of building surface height. In the GWR model, LiDAR data provide the height information of spatial objects, which is the dependent variable, while the brightness values from visible bands of the aerial photo serve as the independent variables. The established GWR model estimates the height at each pixel based on height values of its surrounding pixels with consideration of the distances between the pixels as well as similarities between their brightness values in visible bands. Clusters of contiguous pixels with higher estimated height val ues distinguish themselves from surrounding roads or other surfaces. A case study is conducted to evaluate the performance of the proposed method. It is found that the accuracy of the proposed statistical method is better than those by image classification of aerial photos alone or by building extraction of LiDAR data alone. The results demonstrate that this simple and effective method can be very useful for automatic detection of buildings in urban areas. The approach can be most helpful for studies of urban areas where more suitable but expensive high resolution data are not available.

ABSTRACT Blending of galaxies has a major contribution in the systematic error budget of weak-lensing studies, affecting photometric and shape measurements, particularly for ground-based, deep, photometric galaxy surveys, such as the Rubin Observatory Legacy Survey of Space and Time (LSST). Existing deblenders mostly rely on analytic modelling of galaxy profiles and suffer from the lack of flexible yet accurate models. We propose to use generative models based on deep neural networks, namely variational autoencoders (VAE), to learn probabilistic models directly from data. We train a VAE on images of centred, isolated galaxies, which we reuse, as a prior, in a second VAE-like neural network in charge of deblending galaxies. We train our networks on simulated images including six LSST bandpass filters and the visible and near-infrared bands of the Euclid satellite, as our method naturally generalizes to multiple bands and can incorporate data from multiple instruments. We obtain median reconstruction errors on ellipticities and r-band magnitude between ±0.01 and ±0.05, respectively, in most cases, and ellipticity multiplicative bias of 1.6 per cent for blended objects in the optimal configuration. We also study the impact of decentring and prove the method to be robust. This method only requires the approximate centre of each target galaxy, but no assumptions about the number of surrounding objects, pointing to an iterative detection/deblending procedure we leave for future work. Finally, we discuss future challenges about training on real data and obtain encouraging results when applying transfer learning.

Abstract. In ombrotrophic peatlands, the moisture content of the acrotelm (vadoze zone) controls oxygen diffusion rates, redox state, and the turnover of organic matter. Thus, variably saturated flow processes determine whether peatlands act as sinks or sources of atmospheric carbon, and modelling these processes is crucial to assess effects of changed environmental conditions on the future development of these ecosystems. We show that the Richards equation can be used to accurately describe the moisture dynamics under evaporative conditions in variably saturated peat soil, encompassing the transition from the topmost living moss layer to the decomposed peat as part of the vadose zone. Soil hydraulic properties (SHP) were identified by inverse simulation of evaporation experiments on samples from the entire acrotelm. To obtain consistent descriptions of the observations, the traditional van Genuchten–Mualem model was extended to account for non-capillary water storage and flow. We found that the SHP of the uppermost moss layer reflect a pore-size distribution (PSD) that combines three distinct pore systems of the Sphagnum moss. For deeper samples, acrotelm pedogenesis changes the shape of the SHP due to the collapse of inter-plant pores and an infill with smaller particles. This leads to gradually more homogeneous and bi-modal PSDs with increasing depth, which in turn can serve as a proxy for increasing state of pedogenesis in peatlands. From this, we derive a nomenclature and size classification for the pore spaces of Sphagnum mosses and define inter-, intra-, and inner-plant pore spaces, with effective pore diameters of > 300, 300–30, and 30–10 µm, respectively.

This work presents a systematic study of the kinetic aspects of CO oxidation reaction catalyzed by platinum nanoparticles (NPs) supported on the surface of multiwalled carbon nanotubes (MWCNTs). The investigation presented is closely related to the actual practical task of air purification in enclosed spaces. Therefore, the catalytic reaction was carried out in the presence of an excess of oxygen (5 vol.%) and over a wide range of CO concentrations from 50 ppm to 1600 ppm. For the catalyst characterization, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) were applied. Kinetic modelling based on the Langmuir–Hinshelwood and Mars-van Krevelen mechanisms was taken as a basis, using the results obtained on Pt foil. Simulation of CO oxidation reaction on platinum NPs at temperatures above 90 °C was carried out using a kinetic model describing the reaction mechanism on bulk platinum. The description of the kinetics of CO oxidation reaction on Pt NPs over the entire temperature range, including the low temperatures down to −40 °C, required the introduction of the steps characterizing an additional concerted mechanism related to CO-assisted O2 dissociation. Using the presented model, some predictions of the kinetic behaviour of the system were made.

ABSTRACT The recent detections of CNCN and HNCCN+ are seen as further evidence of the large abundance of NCCN in the interstellar medium. The accurate determination of the abundance of these chemically related compounds from the observational spectra requires the prior calculation of collisional rate coefficients. In this work, we aimed at computing hyperfine resolved rate coefficients for the CNCN–He collisional system. First, we determined a new potential energy surface for the CNCN–He van der Waals complex from which we computed rotationally resolved excitation cross-sections for energies up to 800 cm−1 using the quantum mechanical close-coupling approach. Then, hyperfine resolved transitions between the 30 low-lying pure rotational levels of CNCN were computed for temperatures ranging from 5 to 150 K using an improved infinite order sudden approach. The analysis of the scattering results showed a propensity rule in favour of Δj = ΔF1 = ΔF for the hyperfine transitions and a slight dominance of the odd Δj transitions. Using these data, we carried out non-LTE radiative transfer calculations to simulate the excitation of CNCN in molecular clouds and to constrain the physical conditions of cold dark clouds. Preliminary results showed that the abundance of CNCN derived from observational spectra has to be revisited using these new collisional data.

ABSTRACT Radiative transfer is a key component in almost all astrophysical and cosmological simulations. We present magritte: a modern open-source software library for 3D radiative transfer. It uses a deterministic ray-tracer and formal solver, i.e. it computes the radiation field by tracing rays through the model and solving the radiative transfer equation in its second-order form along a fixed set of rays originating from each point. magritte can handle structured and unstructured input meshes, as well as smoothed-particle hydrodynamics (SPH) particle data. In this first paper, we describe the numerical implementation, semi-analytic tests and cross-code benchmarks for the non-LTE line radiative transfer module of magritte. This module uses the radiative transfer solver to self-consistently determine the populations of the quantized energy levels of atoms and molecules using an accelerated Lambda iteration (ALI) scheme. We compare magritte with the established radiative transfer solvers ratran (1D) and lime (3D) on the van Zadelhoff benchmark and present a first application to a simple Keplerian disc model. Comparing with lime, we conclude that magritte produces more accurate and more precise results, especially at high optical depth, and that it is faster.

In crowding, perception of a target deteriorates in the presence of nearby flankers. Traditionally, it is thought that visual crowding obeys Bouma’s law, i.e., all elements within a certain distance interfere with the target, and that adding more elements always leads to stronger crowding. Crowding is predominantly studied using sparse displays (a target surrounded by a few flankers). However, many studies have shown that this approach leads to wrong conclusions about human vision. Van der Burg and colleagues proposed a paradigm to measure crowding in dense displays using genetic algorithms. Displays were selected and combined over several generations to maximize human performance. In contrast to Bouma’s law, only the target’s nearest neighbours affected performance. Here, we tested various models to explain these results. We used the same genetic algorithm, but instead of selecting displays based on human performance we selected displays based on the model’s outputs. We found that all models based on the traditional feedforward pooling framework of vision were unable to reproduce human behaviour. In contrast, all models involving a dedicated grouping stage explained the results successfully. We show how traditional models can be improved by adding a grouping stage.

Extreme precipitation episodes are very common in Mediterranean area and can lead to serious and catastrophic environmental hazards. They have special incidence during autumn months, September, October and November (SON) with important impacts on society, leading frequently to significant economic losses and mortality. These events have special impact in mountainous areas where steep slopes enhance the effects of extreme precipitation. In mountainous areas rain gauge stations are sparse and normally in lower amount. Due to these reasons it is very important to map with higher accuracy the distribution of extreme precipitation. Also, in mountainous environments precipitation patterns can change in small distances that make the prediction more difficult, but also more important. A better prediction of areas with higher values of extreme precipitation will contribute to a better land use planning and avoid the effects of flash floods, land‐slides and soil erosion recognized as environmental problems. The aim of this paper is testing several well‐known interpolation methods, Inverse Distance Weight (IDW) with weighs of 1, 2, 3, 4 and 5, Local Polynomial (LP) with order 1 and 2, Radial Basis Methods (RBS), particularly Spline With Tension (SPT) and Thin Plate Spline (TPS), and Kriging techniques, Ordinary Kriging (OK) and Ordinary CoKriging (COK) in order to identify the less‐biased method to interpolate extreme precipitation calculated from the 95th percentile (P95) of SON precipitation in a mountainous area located in Portugal. The results show that extreme precipitation increases with the altitude and there are important differences between stations located at higher and lower altitudes. This relation is observed in the omni‐directional semi‐variograms calculated where we identified two major P95 areas coincident with higher elevations. The first one occurred at 12.19 km and the second at 23.57 km. The higher values of P95 are identified at Southeast and Northeast. In contrast, the lower P95 values are identified at Northwest due to lower altitudes and in the Northeast corner as a consequence of rain shadow effect. Prediction with precision of precipitation patterns in mountainous areas is difficult due to lack of data and the complex effect of topography in rainfall, however, it is of major importance in order to identify vulnerable areas. The findings observed in this study are a fundamental contribution to landscape planning and environmental management in areas with higher occurrence and vulnerability to extreme precipitation. Santrauka Gausūs krituliai, ypač būdingi Viduržemio jūros regionui, gali kelti rimtu pavoju aplinkai, lemti katastrofas. Krituliu poveikio zona ypač išsiplečia rudens laikotarpiu, t. y. rugsejo, spalio ir lapkričio (RSL) menesiais, neretai patiriama dideliu ekonominiu nuostoliu, žūsta ar kitaip nukenčia žmones. Statūs kalnu šlaitai sustiprina gausiu krituliu poveiki. Kalnuotose vietovese krituliu kiekio stebejimo stočiu nedaug, jos toli viena nuo kitos, todel labai aktualu tureti žemelapius, tiksliai nusakančius gausiu krituliu pasiskirstyma. Kalnuotose vietovese krituliu pobūdis skirtingu atstumu gali būti skirtingas, krituliu kieki numatyti sunkiau, tačiau tai itin svarbu. Tiksliau numatant vietoves, kur iškrinta daugiau krituliu, galima tikslingiau planuoti žemetvarka, išvengti staigiu potvyniu, nuošliaužu ir dirvožemio erozijos. Tyrimo tikslas buvo patikrinti kelis gerai žinomus interpoliacijos metodus – Inverse Distance Weight (IDW) su 1–5 svertinemis vertemis, Local Polynomial (LP), Radial Basis (RBS), ypač Spline With Tension (SPT), Thin Plate Spline (TPS), – bei Kriging technikas ir Ordinary Kriging (OK) bei Ordinary CoKriging (COK) metodus, siekiant parinkti tiksliausia, kuris leistu interpoliuoti gausius (95 %) kritulius RSL menesiais kalnuotoje Portugalijos teritorijoje. Nustatyta, kad krituliu kiekis dideja didejant altitudei. Reikšmingi krituliu skirtumai nustatyti stotyse, esančiose skirtinguose aukščiuose virš jūros lygio. Šis santykis pastebetas visomis kryptimis apskaičiuotose pusinese variogramose. Jose išsiskiria dvi teritorijos, kuriu P95 vertes didžiausios, ir akivaizdi sasaja su didelemis altitudemis. Pirmoji teritorija 12,19 km, o antroji 23,57 km aukštyje. Didžiausios P95 vertes pietryčiu ir šiaures rytu kryptimis, mažiausios – šiaures vakaru kryptimi, kur altitudes mažos, ir šiaures rytu teritorijos kampe del lietaus “šešelio” efekto. Tiksliai numatyti krituliu pobūdi kalnuotose teritori‐jose apsunkina duomenu trūkumas ir sudetinga topografijos itaka krituliams. Rezultatai ypač parankūs planuojant ir val‐dant dažniems ir gausiems krituliams jautrias teritorijas. Резюме Обильные осадки, особенно характерные для Средиземноморского региона, могут быть опасными для окружающей среды. Зона влияния осадков особенно увеличивается в осенний период – сентябре, октябре и ноябре. Осадки зачастую вызывают большие экономические убытки, гибнут или страдают люди. Влияние обильных осадков усиливают крутые горные склоны. В горных местностях станций наблюдения за количеством осадков немного и расположены они далеко друг от друга, поэтому необходимы карты, на которых было бы точно указано распределение обильных осадков. Характер осадков в горных местностях в зависимости от удаленности может значительно различаться, предвидеть количество осадков чрезвычайно сложно, однако это жизненно необходимо. Зная местности, на которых ожидается большее количество осадков, можно точнее планировать землеустройство, избежать внезапных наводнений, оползней и эрозии почв. Целью исследования было проверить несколько хорошо известных методов интерполяции – Inverse Distance Weight (IDW) с 1–5 значениями весомостей, Local Polynomial (LP), Radial Basis (RBS), особенно Spline With Tension (SPT), Thin Plate Spline (TPS), а также технику Kriging, методы Ordinary Kriging (OK) и Ordinary CoKriging (COK) с целью выявить наиболее точный, с помощью которого можно было бы интерполировать обильные (95%) осенние осадки в горных местностях Португалии. Установлено, что количество осадков увеличивается с увеличением амплитуды. Значительная разница в количестве осадков выявлена на станциях, находящихся на разной высоте от уровня моря. Это соотношение замечено на всех направлениях рассчитанных полувариограмм. На них выделяются две территории, на которых значения P95 наиболее велики и очевидна связь с большими амплитудами. Первая территория находится на высоте 12,19 км, вторая – 23,57 км. Наибольшие значения P95 отмечены в юго-восточном и северо-восточном, наименьшие – северо-западном направлениях, где амплитуды малы, и в углу северо-восточной территории из-за эффекта «тени» дождя. Точнее предвидеть характер осадков в горных местностях представляется затруднительным из-за недостатка данных и сложного влияния на осадки топографии. Результаты исследования окажутся особенно полезными при планировании и управлении территориями, подвергаемыми частым и обильным осадкам.

Abstract. Lightning-generated whistlers lead to coupling between the troposphere, the Van Allen radiation belts and the lower-ionosphere through Whistler-induced electron precipitation (WEP). Lightning produced whistlers interact with cyclotron resonant radiation belt electrons, leading to pitch-angle scattering into the bounce loss cone and precipitation into the atmosphere. Here we consider the relative significance of WEP to the lower ionosphere and atmosphere by contrasting WEP produced ionisation rate changes with those from Galactic Cosmic Radiation (GCR) and solar photoionisation. During the day, WEP is never a significant source of ionisation in the lower ionosphere for any location or altitude. At nighttime, GCR is more significant than WEP at altitudes <68 km for all locations, above which WEP starts to dominate in North America and Central Europe. Between 75 and 80 km altitude WEP becomes more significant than GCR for the majority of spatial locations at which WEP deposits energy. The size of the regions in which WEP is the most important nighttime ionisation source peaks at ~80 km, depending on the relative contributions of WEP and nighttime solar Lyman-α. We also used the Sodankylä Ion Chemistry (SIC) model to consider the atmospheric consequences of WEP, focusing on a case-study period. Previous studies have also shown that energetic particle precipitation can lead to large-scale changes in the chemical makeup of the neutral atmosphere by enhancing minor chemical species that play a key role in the ozone balance of the middle atmosphere. However, SIC modelling indicates that the neutral atmospheric changes driven by WEP are insignificant due to the short timescale of the WEP bursts. Overall we find that WEP is a significant energy input into some parts of the lower ionosphere, depending on the latitude/longitude and altitude, but does not play a significant role in the neutral chemistry of the mesosphere.

AbstractWe consider the following second order evolution equation modelling a nonlinear oscillator with damping$$\ddot{u} (t) + \gamma \dot u(t) + Au\left( t \right) = f\left( t \right),\,\,\,\,\,\,\,\,\,\,\,\,\,\left( {{\rm{SEE}}} \right)$$where A is a maximal monotone and α-inverse strongly monotone operator in a real Hilbert space H. With suitable assumptions on γ and f(t) we show that A−1(0) ≠ ∅, if and only if (SEE) has a bounded solution and in this case we provide approximation results for elements of A−1(0) by proving weak and strong convergence theorems for solutions to (SEE) showing that the limit belongs to A−1(0). As a discrete version of (SEE), we consider the following second order difference equation$${u_{n + 1}} - {u_n} - {\alpha _n}\left( {{u_n} - {u_{n - 1}}} \right) + {\lambda _n}A{u_{n + 1}\ni} f\left( t \right),$$where A is assumed to be only maximal monotone (possibly multivalued). By using the results in [Djafari Rouhani B., Khatibzadeh H., On the proximal point algorithm, J. Optim. Theory Appl., 2008, 137, 411–417], we prove ergodic, weak and strong convergence theorems for the sequence un, and show that the limit is the asymptotic center of un and belongs to A−1(0). This again shows that A−1(0) ≠ ∅ if and only if un is bounded. Also these results solve an open problem raised in [Alvarez F., Attouch H., An inertial proximal method for maximal monotone operators via dicretization of a nonlinear oscillator with damping, Set Valued Anal., 2001, 9, 3–11], namely the study of the convergence results for the inexact inertial proximal algorithm. Our paper is motivated by the previous results in [Djafari Rouhani B., Asymptotic behaviour of quasi-autonomous dissipative systems in Hilbert spaces, J. Math. Anal. Appl., 1990, 147, 465–476; Djafari Rouhani B., Asymptotic behaviour of almost nonexpansive sequences in a Hilbert space, J. Math. Anal. Appl., 1990, 151, 226–235; Djafari Rouhani B., Khatibzadeh H., Asymptotic behavior of bounded solutions to some second order evolution systems, Rocky Mountain J. Math., 2010, 40, 1289–1311; Djafari Rouhani B., Khatibzadeh H., A strong convergence theorem for solutions to a nonhomogeneous second order evolution equation, J. Math. Anal. Appl., 2010, 363, 648–654; Djafari Rouhani B., Khatibzadeh H., Asymptotic behavior of bounded solutions to a class of second order nonhomogeneous evolution equations, Nonlinear Anal., 2009, 70, 4369–4376; Djafari Rouhani B., Khatibzadeh H., On the proximal point algorithm, J. Optim. Theory Appl., 2008, 137, 411–417] and significantly improves upon the results of [Attouch H., Maingé P. E., Asymptotic behavior of second-order dissipative evolution equations combining potential with non-potential effects, ESAIM Control Optim. Calc. Var., 2011, 17(3), 836–857], and [Alvarez F., Attouch H., An inertial proximal method for maximal monotone operators via dicretization of a nonlinear oscillator with damping, Set Valued Anal., 2001, 9, 3–11].

Physical activity is very important for early childhood, especially outdoor activities that add a lot of new experiences. This study aims to check the relationship of children's outdoor activities and parenting styles and children's social skills. The participants are 125 parents of early childhood who attend kindergarten. The research method is a descriptive study using the relational screening model. The results showed that there was a relationship between outside play and parenting style on the social skills of children in their childhood. Democratic parenting styles are found to promote children's social skills, while authoritative parenting styles have a negative correlation with interpersonal skills, the ability to express verbally, self-control, listening skills, emotional management and adaptation to change. In the sub-dimensions of anger management and adaptation to changing skills is a significant difference between authoritative parenting styles and not permissive parenting with children's social skills. Keywords: Early Childhood Social skills, Outdoor Activities, Parenting Styles Reference: Azlina, W., & S., Z. A. (2012). A Pilot Study: The Impact of Outdoor Play Spaces on Kindergarten Children. Procedia - Social and Behavioral Sciences, 38(December 2010), 275–283. https://doi.org/10.1016/j.sbspro.2012.03.349 Bento, G., & Dias, G. (2017). The importance of outdoor play for young childrenʼs healthy development. Porto Biomedical Journal, 2(5), 157–160. https://doi.org/10.1016/j.pbj.2017.03.003 Beyer, K., Bizub, J., Szabo, A., Heller, B., Kistner, A., Shawgo, E., & Zetts, C. (2015). Development and validation of the attitudes toward outdoor play scales for children. Social Science and Medicine, 133, 253–260. https://doi.org/10.1016/j.socscimed.2014.10.033 Boxberger, K., & Reimers, A. K. 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(2019). Outdoor Time, Screen Time, and Connection to Nature: Troubling Trends Among Rural Youth? Environment and Behavior, 51(8), 966–991. https://doi.org/10.1177/0013916518806686 Lindsey, G., Maraj, M., & Kuan, S. C. (2001). Access, Equity, and Urban Greenways: An Exploratory Investigation. Professional Geographer, 53(3), 332–346. https://doi.org/10.1111/0033-0124.00288 Louv, R. (2008). Last child in the woods: Saving our children from nature-deficit disorder. Chapel Hill, NC: Algonquin Books. Maynard, T., & Waters, J. (2007). Learning in the outdoor environment: A missed opportunity? Early Years, 27(3), 255–265. https://doi.org/10.1080/09575140701594400 Moreland, A. D., & McRae-Clark, A. (2018). Parenting outcomes of parenting interventions in integrated substance-use treatment programs: A systematic review. Journal of Substance Abuse Treatment, 89(August 2017), 52–59. https://doi.org/10.1016/j.jsat.2018.03.005 Moriguchi, Y., Zelazo, P. D., & Chevalier, N. (2016). 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International Journal of Disability, Development and Education, 63(6), 623–640. https://doi.org/10.1080/1034912X.2016.1142069 Riany, Y. E., Meredith, P., & Cuskelly, M. (2017). Understanding the Influence of Traditional Cultural Values on Indonesian Parenting. Marriage and Family Review, 53(3), 207–226. https://doi.org/10.1080/01494929.2016.1157561 Saltali, N. D., & Arslan, E. (2012). Parent ’ s Attitudes as a Predictor of Preschoolers ’ Social Competence and Introverted Behavior. Elementary Education Online, 11(3), 729–737. Schoeppe, S., Vandelanotte, C., Bere, E., Lien, N., Verloigne, M., Kovács, É., … Van Lippevelde, W. (2017). The influence of parental modelling on children’s physical activity and screen time: Does it differ by gender? European Journal of Public Health, 27(1), 152–157. https://doi.org/10.1093/eurpub/ckw182 Shi, Y. (2017). Explore Children’s Outdoor Play Spaces of Community Areas in High-density Cities in China: Wuhan as an Example. 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Rapid urbanization rates impact significantly on the nature of Land Cover patterns of the environment, which has been evident in the depletion of vegetal reserves and in general modifying the human climatic systems (Henderson, et al., 2017; Kumar, Masago, Mishra, & Fukushi, 2018; Luo and Lau, 2017). This study explores remote sensing classification technique and other auxiliary data to determine LULCC for a period of 50 years (1967-2016). The LULCC types identified were quantitatively evaluated using the change detection approach from results of maximum likelihood classification algorithm in GIS. Accuracy assessment results were evaluated and found to be between 56 to 98 percent of the LULC classification. The change detection analysis revealed change in the LULC types in Minna from 1976 to 2016. Built-up area increases from 74.82ha in 1976 to 116.58ha in 2016. Farmlands increased from 2.23 ha to 46.45ha and bared surface increases from 120.00ha to 161.31ha between 1976 to 2016 resulting to decline in vegetation, water body, and wetlands. The Decade of rapid urbanization was found to coincide with the period of increased Public Private Partnership Agreement (PPPA). Increase in farmlands was due to the adoption of urban agriculture which has influence on food security and the environmental sustainability. The observed increase in built up areas, farmlands and bare surfaces has substantially led to reduction in vegetation and water bodies. The oscillatory nature of water bodies LULCC which was not particularly consistent with the rates of urbanization also suggests that beyond the urbanization process, other factors may influence the LULCC of water bodies in urban settlements. Keywords: Minna, Niger State, Remote Sensing, Land Surface Characteristics References Akinrinmade, A., Ibrahim, K., & Abdurrahman, A. (2012). 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AbstractConventional Vector Autoregressive (VAR) modelling methods applied to high dimensional neural time series data result in noisy solutions that are dense or have a large number of spurious coefficients. This reduces the speed and accuracy of auxiliary computations downstream and inflates the time required to compute functional connectivity networks by a factor that is at least inversely proportional to the true network density. As these noisy solutions have distorted coefficients, thresholding them as per some criterion, statistical or otherwise, does not alleviate the problem. Thus obtaining a sparse representation of such data is important since it provides an efficient representation of the data and facilitates its further analysis. We propose a fast Sparse Vector Autoregressive Greedy Search (SVARGS) method that works well for high dimensional data, even when the number of time points is relatively low, by incorporating only statistically significant coefficients. In numerical experiments, our methods show high accuracy in recovering the true sparse model. The relative absence of spurious coefficients permits accurate, stable and fast evaluation of derived quantities such as power spectrum, coherence and Granger causality. Consequently, sparse functional connectivity networks can be computed, in a reasonable time, from data comprising tens of thousands of channels/voxels. This enables a much higher resolution analysis of functional connectivity patterns and community structures in such large networks than is possible using existing time series methods. We apply our method to EEG data where computed network measures and community structures are used to distinguish emotional states as well as to ADHD fMRI data where it is used to distinguish children with ADHD from typically developing children.

Researchers increasingly exercise reflexivity with regard to their personal locations, research participants or chosen methodology. However reflexivity about the process of researching as a group, about what shapes research relations between researchers that are often colleagues and friends, seldom happens (Bryan 335, McGinn 559). This may be because writing one’s interpretation of what happened during the collaborative process is risky: as I critically assess the strategies we used inside the semi-private space of collaboration, I also publicly expose the power relations inside and outside of our collaborative practice. The context of our collaboration in a western academic institution as well as the differences between collaborate members (experiential, hierarchical, pedagogical) both structured and enriched our collaboration in specific ways as I will discuss later. The transformative potential of collaboration was critically emphasised in an article that ensued from our research (WASS Collective) and this led me to consider how the alternative forms of student/staff interaction that took place in our project can be seen as simultaneously challenging and reinforcing the disciplinary and hierarchical boundaries that structure higher education. This article, then, focuses on analytical reflections about the ways in which the powerful structures of higher education (enacted here through hierarchies of expertise) and practices of academia (particularly publication procedures) concurrently shape the transformative potential of ‘collaboration’ both as a research and a pedagogic strategy. The collaborative project this article draws on took place in and was funded by the Reinvention Centre, University of Warwick during October-December 2005 and was concerned with feminist activism in Higher Education. We were investigating the transformative potential of gender activism inside the ‘Warwick Anti-sexism Society’. As members of that society ourselves, we were sometimes researching ourselves. The initial decision to make the project collaborative was partly linked to the aims of the Reinvention Centre, which encourages students to become research active and, where possible, to reinvent the spaces in which learning takes place, but was also a reflection of our commitment to feminist ways of working. (Luke and Gore, Peck and Mink) The research collaborate was constituted of staff (2), postgraduates (4) and undergraduates (4) from a range of disciplines (English History, Sociology, Philosophy, Politics) who contributed to the research design, data gathering and analysis of the materials. The end of the project culminated in the submission of an article about our findings to an online sociology journal. As feminist activists, our understanding of ‘collaboration’ was rooted in principles of shared responsibility, equal participation, and a commitment to dialogic exchange as a strategy for change. The rationale for opting for a collaborative strategy was twofold: firstly to contest the usual practices of higher education research and secondly to enrich the research process through engaging multiple voices. This was reflected in how the research was conducted: tasks of data gathering were divided and agreed on according to personal preferences and skills-based expertise so that the workload was equalized and meetings were arranged on a weekly basis to share feedback on the research process and findings, as well as our thoughts on emergent themes, in a challenging yet supportive atmosphere. The final period of collaboration involved analysing data during a day-long group work session, and the writing-up stages included suggested amendments to the final draft from collaborating members. Our collaborative project, as an alternative learning and research strategy, challenged higher education hierarchies and practices in many ways, however, here we will focus on two of its most significant achievements. Firstly, our joint participation in a project regardless of our different locations, both disciplinarily and hierarchically, was disrupting the usual ways in which academic learning usually takes place (mostly through lectures or seminars), thus contesting the structural divide between students and academics, and therefore challenging the institutional framework of the university. Moreover, this challenge to the pedagogic exchange also disrupted the unequal power relations usually at play in typical classroom interaction: in our group discussions opinions were taken into account outside of the framework of reporting to, or seeking approval from an educator, but more in the context of dialogue as a learning strategy (Morley and Walsh). This was especially apparent in the last analytical phase of the project, where our creative voices were both in creative tension with another, whilst seeking to find ways to articulate our differences without losing the essence of the argument. Our egalitarian vision of collaboration was adhered to through to the last stage of our research and impacted on decisions about the authorship of the article we were submitting for publication. Although our names all appear on the paper, we opted for a collaborative name that reflected our affiliation with the student society that we were also researching: thus, the author of the paper became the Warwick Anti-Sexism Society Collective. We considered the option of listing our names alphabetically with et al. next to the first name, but felt that it would not reflect adequately our conceptualization of collaboration. Acquiring credit for research and publications is key to gaining academic achievement and is often a resource that is scarce for junior researchers and even more so for undergraduates. Our project, and particularly the decisions made with regard to authorship, successfully challenged the hierarchies of academia: our strategy of sharing credit uniformly for the research between academic staff and students enabled us to contest the prevalent practice of senior researchers being credited as the main authors. This also allowed us to shift the power distribution in the university in general by introducing and advocating a research practice whose rationale centres around students and junior researchers being recognised as authors on their own terms. As suggested, our collaboration was also constrained by the organisation and practices of higher education and in this sense, our research can be seen as highlighting the power structures of academia: ‘Throughout this research project, we have been forced to reflect on how we develop and implement praxis within and through the powerful hierarchies of academia.’ (WASS Collective 8) Reflecting on the wider constraints that structured our research output also helps to identify which factors are still limiting the transformative potential of collaboration. The first way in which our collaboration reinforced existing structures within academia was reflected in our collaborative discussions. Although power relations are inherent within any research process, considering how they are organised can shed light on how certain types of expression come to be privileged. The dialogic learning exchange that took place during group sessions enabled certain types of ‘dominant’ skills that are prevalent in higher education to become the main communicative strategy; this in turn allowed group members who were familiar with certain academic practices and therefore proficient in these skills to have more input in the generation of knowledge from the data. The hegemony of ‘dominant’ skills such as assertiveness, leadership, and rhetorical expertise continues to be part of the ways in which academia is structured through “the replication of taken-for-granted forms of dialogue and exclusion” (Knights 136). This is played out in day-to-day pedagogic practices where students are judged, and sometimes assessed on, their participation in seminars and performance in presentations (Fejes 31), but where listening and facilitating skills continue to be undervalued. In this sense the limits of our collaboration in creating innovative learning strategies lie right at the centre of our practice so that the communicative tools we used to collaborate were instrumental in partly reinstating the hierarchies of knowledge production (Mahony et al.). Our project can, however, also be seen as reinforcing existing hierarchies within academia because of the allocation of tasks during the research process. While all students (undergraduate and postgraduate) were involved in gathering data for the research, the members of staff were involved in the writing of the article and the production of a final draft that was open to amendments by all members of the collaborate before submission. This meant that responsibility was not divided equally between us, and that participation was not as egalitarian as we had hoped. While I am not implying the superiority of some part of the research process, it is clear that the development of high quality writing skills is key to establishing one’s position within academia. It could be argued that allowing for participants to develop and improve certain skills by matching them to specific tasks appeared to be connected to an already existing hierarchy. However, the writing strategy we adopted managed to partly resolve this division of labour issue. All members could suggest amendments to a draft crafted by the two staff members, changes were then discussed by all collaborate members via e-mail and eventually some agreed revisions were included into a later draft by the academic staff. This strategy not only allowed all members to have dialogic input into the article, but also formed part of a pedagogic exchange where junior researchers were part of the process of developing writing skills for publication purposes and gained insights into the craft of academic writing. This was developed through modelling best practice of the writing process: crafting notes of a joint thinking session into a first coherent draft of the article. The most significant constraint to the transformative potential of collaboration was the pressure of working towards a publishable piece of research. This was partly because of the contrast between the quite independent data gathering stages of the research and the more intensely collaborative writing-up stage. Most importantly publishing constraints impacted on our project in powerful ways. Firstly, we found that both the word limit and the format of the article restricted and sometimes erased the interesting complications and differences that were at the heart of our collaboration. For example, our different analyses of the data gathered were partly simplified into one consistent story, to preserve the coherence of our argument but also because of space issues. The stylistic demands of traditional academic journals could not fully capture the messiness and creative tensions arising from collaborative work. Disordered exchanges and mixed up thoughts were at the heart of the collaboration and in many ways created the fuel for the article. For instance, the process of collaboratively crafting a theoretical framework for the article proved a challenging and complex exercise whose strength lay in its emergence from differences and disorder, we were not able to render this fully in writing. The enterprise of publishing our research was also connected to and strengthened already existing academic structures and practices. For example, the likelihood of the article being accepted for publication relied at least partly on the expertise of academic staff and their familiarity with publication standards and procedures. The deadline-meeting pressure of producing an article meant that time constraints prevented us from producing the article through a joint writing session as we had initially planned. Even though we placed a high value on doing the research itself, as our project was geared towards a publication from the outset it was necessarily very much shaped by its demands. However, ways to alleviate these constraints could have been explored by employing alternative methods of reporting our research such as performances, fiction writing and diaries that may have allowed for a more comprehensive and multiple account of our research. Collaborative work between students and teachers is an empowering and difficult exercise that both strengthens and challenges the powerful hierarchies and practices of academia. In our case students’ learning and expertise have benefited from this project further through the continuation of the collaboration: members are currently involved in jointly revising the article according to referees’ report and are preparing papers that will be jointly presented at various UK postgraduate conferences this summer. Our project also revealed that practicing alternative strategies inside a single collaboration allowed for both expertise-led and student-led forms of work and enabled skills and merit to be more evenly distributed within academia. Most importantly, as we learnt through the production of an academic article, the incompatibility of this hierarchical vestige of academic practice with collective ways of working had powerful implications on our finished work. Hopefully this will constitute the site of future challenges to traditional practices in academia and will encourage alternative ways of producing publishable academic work. Notes Thank you to all members of the Wass collaborate for being supportive of my writing reflections about our project, and also for their insightful comments and encouragements about this piece. Thank you to Danny Beusch for his constructive and honest comments on an earlier draft of this article. References Bryan, L., et al. “Processing the Process: One Research Team’s Experience of a Collaborative Research Project.” Contemporary Family Therapy 24.2, (2002): 333-353. Fejes, Andreas et al. “Learning to Play the Seminar Game: Students’ Initial Encounters with a Basic Working Form in Higher Education.” Teaching in Higher Education 10.1(2005): 29-41. Knights, Ben. “Group Processes in Higher Education: The Uses of Theory.” Studies in Higher Education 20.2 (1995): 135-146. Luke, Carmen, and Jennifer Gore, eds. Feminisms and Critical Pedagogy. New York: Routledge, 1992. Mahony P., et al. “Threshold Assessment and Performance Management: Modernizing or Masculinizing Teaching in England?” Gender and Education 16. 2 (2004): 131-149. McGinn, Michelle, et al. “Living Ethics: A Narrative of Collaboration and Belonging in a Research Team.” Reflective Practice 6.4 (2005): 551-567. Morley, Louise, and Val Walsh. Feminist Academics: Creative Agents for Change. London: Taylor & Francis, 1995. Peck, Elizabeth, and Joanna Stevens Mink, eds. Common Ground: Feminist Collaboration in the Academy. Albany: State U of New York P, 1998. WASS Collective. “Gender Transformations in Higher Education.” Sociological Research Online 27.1 (2006). Citation reference for this article MLA Style Perrier, Maud. "Reflections on Practicing Student-Staff Collaboration in Academic Research: A Transformative Strategy for Change?." M/C Journal 9.2 (2006). echo date('d M. Y'); ?> <http://journal.media-culture.org.au/0605/08-perrier.php>. APA Style Perrier, M. (May 2006) "Reflections on Practicing Student-Staff Collaboration in Academic Research: A Transformative Strategy for Change?," M/C Journal, 9(2). Retrieved echo date('d M. Y'); ?> from <http://journal.media-culture.org.au/0605/08-perrier.php>.

Being is an empty fiction. The “apparent” world is the only world: the “true world” is just a lie added on to it… —Nietzsche. Anna Poletti: I’m attracted to autobiography in a non-narrative context because I’m very interested in texts that people create that demonstrate their thinking or their fantasies or their processing, generally.Lauren Berlant: Right, in that sense it’s autobiography in your larger sense of what autobiography is: a record of […] processing. —Anna Poletti and Julie Rak with Lauren Berlant. The medium is the message. —Marshall McLuhanWelcome to the M/C Journal issue on automediality. If “automediality” sounds like another academic buzzword to you, you are right. But it is more than a buzzword for scholars interested in exploring the significant role of mediation in auto/biographical engagement. Automediality is, we think, an incredibly useful way of framing and grouping scholarly investigations of the processes and practices that people engage when they mediate their lives and selves in a range of auto/biographical forms.We are incredibly excited to bring you this vibrant collection of research about what we are calling “automediality,” but first it is useful to lay some groundwork in terms of explicitly articulating what we think automediality is and does, and why we think it is necessary.As life writing scholars exploring contemporary examples of digital auto/biography in our own research, we were both struck by the need for a new definition of auto/biography that expands beyond text, beyond narrative, beyond subject in any complete sense or form, to reflect the multiplicity of ways that lives are lived and recorded using new media today. We each found ourselves limited, at times, by existing assumptions about what auto/biography traditionally is. Sidonie Smith and Julia Watson, in their field defining work Reading Autobiography, offer an etymological cue that summarises the prevailing use and perception of autobiographical work: “in Greek, autos denotes ‘self,’ bios ‘life,’ and graphe ‘writing.’ Taken together in this order, the words self life writing offer a brief definition of the autobiography” (1).If “autobiography” has denoted a way to write the self from the location of the self, automediality points to the range of media forms and technologies through which people engage in digital, visual, filmic, performative, textual, and transmediated forms of documenting, constructing and presenting the self. Smith and Watson introduce automediality as a possible theoretical framework for “approaching life storytelling in diverse visual and digital media” (Reading 168). Originally developed by European scholars such as Jörg Dünne and Christian Moser, the term was introduced in order “to expand the definition of how subjectivity is constructed in writing, image, or new media” (Smith and Watson Reading 168).Conjoining autos and media, the concept redresses a tendency in autobiography studies to consider media as “tools” for rendering a pre-existent self. Theorists of automediality emphasize that the choice of medium is determined by self-expression; and the materiality of the medium is constitutive of the subjectivity rendered. Thus media technologies do not simplify or undermine the interiority of the subject but, on the contrary, expand the field of self-representation beyond the literary to cultural and media practices. New media of the self revise notions of identity and the rhetoric and modalities of self-presentation, and they prompt new imaginings of virtual sociality enabled by concepts of community that do not depend on personal encounter. (Reading 168)Looking at auto/biographical practices from a framework of automediality moves away from a conception of texts as able to capture and transmit preexisting selves, lives and identities, and towards an understanding of selves, lives and identities as constructed by and through textual and media practices. It is through creating an autobiographical text that the “self” a person thinks they are comes into being. The mode of creation here, be it a Facebook status update, a memoir, or an alt account, for example, is situated within networks of power, meaning and social capital to shape ways of being a “self” in a particular environment or context. Automedial reading takes all of these formative elements into consideration.Julie Rak suggests that automedia “describes the enactment of a life story in a new media environment” (155), but we think that the term is even more useful as a framework or approach to studying not only new media life stories, but auto/biographical practices as they are enacted in a range of media forms, analogue and digital alike. Importantly, our aim here is not simply to introduce another buzzword, but rather to draw attention to the current need to rethink the significant role of mediation in auto/biographical production, performance, and practices. As Rak points out, “it is time not only to rename the practices we study, but also to think critically about online life as life, and not as the texts many of us are more used to studying, which are meant to represent a life” (156). This kind of critical rethinking about how media is embedded in the living of lives, and the scholarly shift that Rak suggests from examining representation in texts to examining “online life as life” is crucial to the notion of automediality. And it has us—the editors of this issue—divided. A Conversation between EditorsÜmit: choosing “subject” and “process” over “text.”I think what automediality is, which is different to auto/biography, is process rather than product. Automediality allows us to explore how our lives intertwine with different mediums and technologies resulting in new subjects, but subjects in motion. There is no product, there is no complete narrative, there is no snapshot that captures the subject. The subject is always developing, always in motion, always in the “process of doing” (Rak 156), of being and becoming. It is a “moving target” as Smith and Watson suggest (“Virtually” 71). And therefore, automediality, as Rak suggests, is the process of living: living in relationship with media. Where as an autobiographical enquiry has usually (not always) involved the study of a subject in a complete form (although susceptible to other “versions”)—a text in other words, which can be examined by itself—an automedial enquiry has to adapt to the fact that there isn’t a product that can be examined in isolation. As Emma has argued elsewhere, we can never hold “a single cohesive version” of automedial subjects in our hands and we never reach “the end” of a subject’s self-representation as long as they continue to “post” (“Self-Branding” 75). What we are exploring as scholars of automediality is a process of living. How people live, create and present themselves, participate, narrativise, and simply “be” in different spaces, using different mediums and technologies. The mediated lives and subjects that we’re exploring in this issue require new language, new words and definitions. We are not dealing with “texts,” although there are textual components, we are not dealing with “narratives,” although one (or many) is (or are) always in formation (see Rak 156), and most importantly, we are not dealing with “products,” that hold any significance in isolation. What we are dealing with are processes: processes of being, doing, creating, and distributing the self, in relationship with media and their affordances, limitations and participants. My objection to language such as “text” is that it implies something tangible, taking for granted the ephemerality of the subjects of automediality. So often in my research I have taken a “snapshot” of a subject (in the form of a YouTube video, for example) and treated it like a text ready for analysis only to find when I revisit it that it has changed, been edited or contradicted, or completely erased (see Kennedy). And when we treat “snapshots” as “texts” for analysis I think we miss the most important point: that is the process through which the subject was and is being formed (in relationship with the medium, its technologies, and the people and things that congregate and participate in that space). We need to expand the way we explore mediated subjects and lives and “automediality” allows us to do this—it gives us a “space” in which to develop new language and methods of enquiry.Emma: texts are vital to studying automediality.Elsewhere, I have suggested that textuality is key to a definition of automediality: “The aim of an automedial approach is to discover what texts can tell us about cultural understandings of selfhood and what it means to portray ‘real’ life and ‘real’ selves through media. The emphasis is on thinking critically about mediation” (Girls, 22). However, Ümit’s thinking about automedia as process has been instrumental to progressing how I am defining and thinking about automediality. For me, though, (and perhaps my background in literary studies is showing here), framing autobiographical production and performance as texts that we can read is a useful framework that allows us to disentangle and examine abstract, slippery concepts like being, living, identity, and selfhood in process in a way that brings the roles and effects of mediation into sharp focus.Retaining the terminology around texts and textual practices—specifically that branch that is concerned with cultural production—also means that we can observe the labour of auto/biography, which is important for thinking about the economies in which automediation occurs as well as acknowledging the work that goes into creating these self-presentations or performances. It takes skills, labour, literacies, and—for me—nuanced understanding and facility with crucial modalities of reading to participate and "play" in any kind of media form. My definition of reading is broad: people read meaning, identities, lives, media, and the world around them in order to figure out how they fit into any given context, and it is the texts produced in even the most fleeting or participatory automediation that record or hold traces of this work, this process, that we as scholars can then examine.The spirit in which I apply “text” is deeply influenced by the field of semiotics within Cultural Studies. The work of semioticians like Saussure, Althusser, Derrida and Lotman that I studied during my undergraduate degree leads me, like many literary scholars, to think about not only cultural products like books and media as texts, but also bodies, surfaces, ephemeral and immaterial performances, and a range of autobiographical practices as texts. As agents we create meaning by reading, decoding, interpreting, and negotiating texts. The work of mediation, for me, is deeply connected to textual practices.I still think that texts—as well as the practices and processes that go into creating, distributing, and reading them—are a productive framework for examining strategies of self-presentation and identity performance. However, Ümit’s observations around process (articulated in her short essay “Vulnerability” and developed here) is particularly vital to thinking about the context for the participation of produsers in media economies where automedial production is often fleeting, ephemeral, and in flux. And I think that the importance of process in analysing more (apparently or materially) stable media is important, too. One way of thinking about a middle ground between text and subject is by considering the concept of becoming as central to the conceptual framework of automediality. Ümit: finding a middle ground.I agree our difference of opinion about viewing these subjects as texts comes from our different disciplines. For you, Emma, the word “text” is important because it emphasises the agency and labour involved in its creation. As a communications and media scholar, I operate on the assumption that communicating the self involves a huge amount of conscious and unconscious work. I take the agency and labour involved in mediating the self for granted. I still have an issue with “text,” however, as taking the process through which it was created for granted. I do concede, though, that we can’t completely disregard the products of mediation, because there are products (as long as we agree that they are in motion), and these are worthy of study.Although mediated subjects and texts can be fleeting and ephemeral, the fact that they are mediated, as you suggest, means that to some extent they are traceable. The mediation of the self means we can see and track its progression, its influencers, its forms, its relationships and dialogues. Although it is changeable and deletable, “doing” (living in relationship with media) leaves a record. On YouTube, for example, I can see the interactions that take place, through comments, likes and subscriptions, and I can therefore trace the subject as it changes. Mediating the self in this way materialises the process of self-formation. Automediality illuminates the process and makes it accessible to us to research. I think the concept of becoming is a perfect middle ground. “Becoming” as a Middle GroundWe are interested in using the concept of automediality to unpack and examine how selves and lives are brought into being through media forms by examining, simultaneously, both the process of mediation and the product (i.e. the autobiographical subjects and text). A crucial part of this examination is attending to the process of construction, of the process through which the textual self is mediated. One way of thinking about this in relation to the construction of lives and selves, is by thinking about how the concept of becoming is traceable in mediation.Rob Cover’s discussion of becoming in social networking is influential to our thinking here. Cover, drawing on Judith Butler, explains that underlying his approach is “the idea that identity and subjectivity is an ongoing process of becoming, rather than an ontological state of being” (56) and he argues that looking at the practices and artifacts of online identity performance can reveal the intricacies of identity in process. Also important here is the work of Stuart Hall who, in 1989, wrote about becoming in terms of how it is implicated in identity as a cultural practice or process:Cultural identity […] is a matter of 'becoming' as well as of 'being'. […] It is not something which already exists, transcending place, time, history and culture. Cultural identities come from somewhere, have histories. But, like everything which is historical, they undergo constant trans-formation. Far from being eternally fixed […], they are subject to the continuous ‘play’ of history, culture and power. Far from being grounded in a mere 'recovery' of the past, which is waiting to be found, and which, when found, will secure our sense of ourselves into eternity, identities are the names we give to the different ways we are positioned by, and position ourselves within, the narrative of the past. (70)Hall’s description of becoming as the process by which identity is continually brought into being has parallels to how we are thinking of mediation and life narrative in this issue. Hall is speaking about reading and representing identity, about the processes and products through which people enact, express, perform, and consume identity categories. Similarly, we are looking at subjectivities and identities in process, and we both agree that automediality as a conceptual tool and classifying label turns our attention to the ways in which people identify themselves and others using media. Media use, here, encompasses practices of engagement in terms of both consumption and creation. And, increasingly, users participate by engaging in both production and consumption simultaneously, becoming produsers—a term coined by the editor of this journal, Axel Bruns (2). Bruns’s notion of produsers illustrates the complex relationship between consumers, producers and users in the current media economy (2). One of the significant aspects of an automedial enquiry is the blurring of boundaries between creators and consumers. Automedial subjects are created in dialogue with the other participants in the space. The lives and identities are not only merged with the medium and technologies involved in their creation, but also with the other produsers in the space. This is critical when we begin to explore how to research automediality, as an automedial enquiry demands automediation of the researcher. In order to explore these subjects, the researcher must participate, to some extent, in the practice. Exploring subjects on social media, for example, requires the researcher to create an account and therefore participate in the same activity they are observing/consuming/researching.Questions for Automedial EnquiryTaking these ideas from theory to practice, from our point of view, reading auto/biographical texts and practices through a framework of automediality involves asking some of the following questions and paying attention to some of the following elements:What are the affordances, constraints and features of this medium that have shaped how a subject can inscribe, perform, or construct a self-presentation? As Nancy Baym writes, “our ability to construct an online self-presentation ... is limited and enabled by the communicative tools, or affordances, a platform makes available and our skills at strategically managing them” (124).What networks of power traverse this technology, this medium, and thus this mode of self-presentation?How does this performance of selfhood engage the different autobiographical “I”s: the narrating self and the narrated self; the subject and its creator; the online self and the offline IRL (in real life) self or selves. Although, as Smith and Watson state, “theorists of media and autobiography […] approach the constructed self not as an essence but as a subject” (Reading, 71), we have to acknowledge the person or constructs that exist outside of (and informs) the performance. How do these different facets of the self, and identities, speak to each other in automedia? In what networks of production and consumption does the automedia exist? How is the audience positioned in relation to the text or subject?Surface reading: the textual elements that form the interface between reader and story can tell us about what forces are shaping the self-presentations within the text, and also how the reader is positioned in relation to the autobiographical narrative. What does a surface reading reveal about how the self is being constructed by both media conventions and cultural meanings? The possibility of multiple and fragmented selves. The self that a subject performs or creates in one media platform may be a very different self that they perform in another or that they feel themselves to “be” in “real” life. What is the relationship between these selves? How do they inform and speak to each other?Authenticity is always suspect. Rather than a concrete guarantee that the media presentation correlates truthfully or sincerely to the IRL (in real life) identity or life of the narrator, authenticity in automedia is “an effect created by the form and style” of an auto/biographical performance (Maguire Girls, 11; drawing on Poletti Intimate, 28-9; emphasis added). Thus, it is less useful to weigh up how authentic or how real a particular self-presentation or media form is, and more interesting to examine how particular media constructs or creates effects of authenticity, or makes appeals to truth/authenticity. And finally, method: How can we develop methods to explore automedia which critically examine the text/subject, as well as the “process of doing” (Rak) through which the text/subject is being and “becoming” (Hall). Introducing the ArticlesEach of these excellent articles responds to technological effects on selfhood. By canvassing a range of media forms and approaches to conceptualising the mediation of lives and selves, our contributors’ ideas probe new directions for automediality as a framework for reading and thinking through self-mediation.The feature article, authored by Anna Poletti and Julie Rak, proposes that RuPaul’s Drag Race demonstrates automedia in action and suggests that the reality TV show, by modelling “queer time,” presents a challenge to dominant (straight) patterns of temporality in life narratives. This piece presents an argument for considering how identities that have been positioned as marginal are able, through automediality, to reconfigure understandings of what a life and a self can look like.Wes Hill addresses a key claim that we are making when we talk about autmediality: that media interfaces and contexts shape and construct the forms of selfhood that are brought into being through them. Hill takes the case study of artist and filmmaker Ryan Trecartin and argues that Trecartin’s videos demonstrate a fragmented set of identities that are deeply constituted by a style of performance that Hill calls “Internet-era camp.” Here, Internet-era camp becomes a mode through which to constitute the self through fragmented sets of intertextual and affective meanings. Emily van der Nagel highlights the multi-faceted nature of the mediated self through her investigation of Alt (alternative) accounts on Twitter. Her article demonstrates the way people use different accounts on the same platform for different facets of the self, and for different audiences. Isabel Pederson and Kristen Aspevig extend our discussion of automediality to explore agency and consent in the example of children producing their own automedial subjects and texts on YouTube, in the form of toy reviews. Kylie Cardell explores the digital self-tracking device many of us wear on our wrists, the Fitbit, and asks whether this wearable technology constitutes a diary. In her article, Cardell examines how a Fitbit can become an almanac for self-improvement, where the constant tracking of our physical behaviour changes the way that we live.Anu A Harju critically examines the world of “fatshion” blogging to reveal the relational way “fatshionistas” are formed in dialogue with medium, community and market. Harju situates the self as a product of relations, “borne out of them as well as dependent on them.” Chad Habel takes up masculine gender performance in video games by investigating how genre facilitates (or doesn’t) particular modes of identification by coaxing aggressive gameplay.Mick Broderick, Stuart Marshall Bender and Tony McHugh take a look how artificial intelligence technologies are currently being used to create immersive virtual reality experiences. They question the use of trauma in such projects, and suggest that affect—particularly when used to explore suffering within virtual worlds—needs careful thought moving forward with these technologies.ConclusionThis collection of interdisciplinary scholarship is an exploration of the different ways that people mediate the self. Focusing on mediation as a process that brings the subject into being, these essays explore the connections between lives, selves, identities and media technologies. The textual constructs that hold selves together become traces or products that can perform social functions, but they also have immense richness as objects of study. By taking apart and examining the processes and effects of mediation on life narratives, as scholars we are able to re-focus the microscope on the becoming of lives, selves and identities that are constructed in autobiographical texts. In seeking contributions for this collection, we were guided by two key questions: How do people mediate their identities, selves and experiences? How do media forms and conventions limit or facilitate the possibilities for particular kinds of selfhood to be articulated? Scholars of life narrative warn us that “the self” is not a unified and pre-existing entity that can simply be transcribed or translated through media. Rather, the self is brought into being through writing—or mediation. Media technologies like the camera, the diary, social media platforms, and books each have conventions, affordances, abilities and limits that both enable and restrict the kinds of self-presentation that are possible. Particular media bring particular subjectivities to life. It is our opinion that examining such sites and modes of automediality can tell us about the ways in which “technologies and subjectivity” are connected (Smith and Watson “Virtually” 77), and this is what we hope this collection of work offers to scholars of media and life narrative, as well as those working in interrelated fields. But this is only the beginning. The interfaces between life narrative and media technologies remains an exciting space for new ideas and theories to flourish.Future avenues for investigation of automediality might include examining: the platforms, mediums and technologies of automediality; the affordances of automediality for alternative narratives and identities; the vulnerabilities of mediated narratives and identities; the mediated self as brand/consumable product; cases that explore when automediality is lasting and permanent and when it is ephemeral and shifting; and multiple methodologies for investigating the mediated self, particularly in the context of digital media. An upcoming development that we’re particularly excited about is Anna Poletti’s forthcoming monograph Biomediations which will, we expect, move this thinking forward again.We hope that this issue of M/C Journal inspires more ideas about how media shapes the kinds of selves we think we are, now, in the past, and into the future. 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