Glass Model Research Articles

Designing a Mobile e-Coaching App for Immigrant Informal Caregivers: Qualitative Study Using the Persuasive System Design Model.

Informal caregivers are vital in caring for their family and friends at home who may have illnesses or disabilities. In particular, the demands for caregiving can be even more challenging for those with limited resources, support systems, and language barriers, such as immigrant informal caregivers. They face complex challenges in providing care for their relatives. These challenges can be related to sociocultural diversity, language barriers, and health care system navigation. Acknowledging the global context of the increasing number of immigrants is essential in designing inclusive mobile health apps. This study aims to investigate the needs of immigrant informal caregivers in Sweden and discuss the application of the Persuasive System Design Model (PSDM) to develop an e-coaching prototype. By addressing the unique challenges faced by immigrant informal caregivers, this study will contribute to the development of more effective and inclusive mobile health apps. The participants were considered immigrants and included in the study if they and their parents were born outside of Sweden. Through various channels, such as the National Association of Relatives, rehabilitation departments at municipalities, and immigrant groups, we recruited 13 immigrant informal caregivers. These immigrant informal caregivers were primarily women aged 18 to 40 years. Most participants belonged to the Middle Eastern region whereas some were from North Africa. However, all of them spoke Arabic. We used semistructured interviews to gather data from the participants in Arabic, which were translated into English. Data were analyzed using thematic analysis and discussed in relation to the extended PSDM. The needs of the caregivers were compared with the description of persuasive design principles, and a design principle was chosen based on the match. The PSDM was extended if the need description did not match any principles. Several brainstorming and prototyping sessions were conducted to design the mobile e-coaching app. Immigrant informal caregivers have various needs in their caregiving role. They reported a need for training on the illness and future caregiving needs, assistance with understanding the Swedish language and culture, and help with accessing internet-based information and services. They also required recognition and appreciation for their efforts, additional informal support, and easy access to health care services, which can be important for their mental health. The PSDM was adapted to the informal caregiving context by adding "facilitating conditions" and "verbal encouragement" as additional persuasive design principles. This study also presents the subsequent mobile e-coaching app for immigrant informal caregivers in Sweden. This study revealed important immigrant informal caregivers' needs based on which design suggestions for a mobile e-coaching app were presented. We also proposed an adapted PSDM, for the informal caregiving context. The adapted PSDM can be further used to design digital interventions for caregiving.

Existence of traveling wave fronts for a diffusive Mackey–Glass model with two delays

Based on the diapause effect, a diffusive Mackey–Glass model with distinct diapause and developmental delays is proposed. By constructing appropriate upper and lower solutions and employing the inequality techniques, some sufficient conditions on the existence of traveling wave fronts are obtained. These results not only improve but also supplement some existing ones. Moreover, two numerical examples are provided to demonstrate their reliability and feasibility.

Unusual energy–structure–property relation in a metallic glass coupled with temperature-dependent relaxation memories

Elucidating the individual effects of high- and low-temperature relaxations on the internal structure and material properties is a fascinating theme in the field of metallic glasses because it can lay the foundation for an advanced glass-property tuning scheme through the control of different types of relaxations. In this study, several glass models were constructed using melt-quenching (MQ) processes, in which high- and low-temperature relaxations were controlled by their cooling rates. We found unusual energy–structure–property relationships; even when the glass alloys had equivalent potential energies (or free volumes), they exhibited different local-order development, elastic stiffness, and plastic deformation properties, which depended on the thermal histories in the glass-forming MQ process. The local-order development was primarily affected by the high-temperature relaxation occurring at approximately the glass transition temperature. Meanwhile, the plastic deformation behavior of the metallic glasses was significantly affected by both low- and high-temperature relaxations. We also found an interesting relaxation memory effect in the glass alloys constructed by the present MQ processes; the glass alloys exhibited an atomic-scale dynamic that was affected by the temperature-dependent relaxation memories (i.e., high and-low-temperature relaxation memories) of previous MQ processes. These results provide new insights into the relaxation physics of glass-forming liquids and imply the possibility of an advanced tuning scheme for metallic glasses.

Direction control of electromagnetic beam scattering by physically stacked cascaded coding metasurfaces

Coded metasurfaces build a bridge between the physical world and digital worlds, making it possible to manipulate electromagnetic waves and implement programmable metamaterials through digitally coded sequences. This “digital metasurface” based on binary digital logic greatly simplifies the design process of the metasurface and improves the flexibility of regulating electromagnetic waves. Based on the principle of Fourier convolution addition, a physical superposition cascaded metasurface is designed. The metasurface unit consists of three dielectric substrates and four “H”-shaped copper metal patch boards. The addition of most coding metasurfaces is to add two basic coding metasurfaces through the addition rules between digital codes to obtain a new coding sequence, and the new coding sequence has the characteristics of the previous two coding sequences. We propose a physically superimposed cascaded encoding metasurface. By physically superposing two different sequences of metasurfaces, the cascaded metasurface formed after superposition also has the characteristics of the first two basic coding sequences. We experimentally verified the proposed idea using two different dielectric materials, and there was good consistency between the experiment and simulation, thereby verifying the consistency of the metasurface cascade and the phase-encoding element surface addition principle. This design approach has potential applications in multifunctional photonic devices.

A Bibliometric Analysis on Cooperatives in Circular Economy and Eco-Innovation Studies

Cooperatives address societal challenges embracing values beyond mere profit-oriented production. Considering the ongoing shift to achieve efficient use of resources and increased circularity, cooperatives should be better equipped to incorporate circular economy (CE) and eco-innovation (EI) into their strategies (compared to regular enterprises). This paper reviews the scholarly literature focusing on the application of CE and EI within cooperative studies with the aim to understand the relationships between these topics, identify the existing scholarly communities, and to observe salient research themes. This study refined the method of van den Hoven and Rubalcaba (2016) to conduct a two-step bibliographic review of documents: a thematic analysis of citation data from Scopus (including a manual review of 16 papers) was followed by a bibliometric analysis of 101 documents from Web of Science (using R-Studio’s Biblioshiny). Our results identified three intellectual clusters of cooperative studies focusing on the downstream of CE: (1) industrial ecology; (2) recycling; and (3) waste management. Our study also revealed an emerging scholarly field focused on cooperatives and CE, and with little attention to EI. These findings aim at catalyzing the integration of cooperatives more effectively into scholarly discussions, suggesting that environmental sustainability should be recognized as an additional principle of the cooperative identity—providing a wider perspective that enhances interest in the research of these topics and their interconnections.

Spin Glass Model for GaAs/AlGaAs Quantum Wells Doped by Nonmagnetic Impurities near the Metal-Insulator Transition

Spin Glass Model for GaAs/AlGaAs Quantum Wells Doped by Nonmagnetic Impurities near the Metal-Insulator Transition

Flow-Induced Noise Characteristics Analysis of a Pipeline Structure in a Cabin Rigid Corner

The acoustic radiation characteristics of pipeline structures caused by turbulent fluctuating pressure are among the most important acoustic radiation sources in vessel cabins. Studying the vibro-acoustic characteristics of pipeline structures is of great relevance to engineering. The turbulence fluctuation pressure of pipeline structures’ inner surfaces was numerically analyzed by using the large eddy simulation (LES) method. At first, the vibro-acoustic differential equation of the pipeline structure system was derived by defining the fluctuation pressure as the excitation loading. According to the acoustic radiation characteristic in the quarter-infinite space, which had a combination of two rigid wall interfaces at the same time for the pipeline structures in the vessel cabins, the double reflection method, mirror image method and elastic wave Graf addition principle were applied, and the analytical function of the acoustic radiation for the cylindrical shell was derived. For the pipeline structures in the quarter-infinite acoustic space, for example, the numerical calculation for the acoustic radiation of cylindrical shell was carried out, which was excited by the turbulent pulsating pressure. Finally, the influence of inner flow velocity, frequency, and pipeline installation position were compared using numerical analysis. The results can provide technical support for the acoustic design of pipeline structure systems with complex acoustic boundaries.

A physically based strength prediction model for glass

The strength of glass has been a subject of great interest for more than one hundred years. Due to the stochastic nature of glass, governed by microscopical surface flaws, glass plates exhibit large variations in fracture strength. The aim of this work is to propose a new strength prediction model for glass, named the Glass Strength Prediction Model (GSPM) that captures the nature of fracture initiation in glass, spanning from rate dependence to size effects. We aim for the presented model to be applicable in modern design processes and provide a procedure to facilitate input parameter calibration for glass plates from different suppliers. GSPM is a Monte-Carlo based model that combines the theories of linear elastic fracture mechanics (LEFM) and sub-critical crack growth (SCG) to generate virtual tests on a representative sample of glass plates. The stress evolution in the glass plates is obtained from finite element (FE) simulations. The model results in representative fracture strength distributions that span the probable fracture initiation instances with respect to time, location and stress level. We also demonstrate how the GSPM can be used to trigger fracture in constitutive models applied in FE simulations. This feature provides the option to investigate scenarios including multiple glass plates with interdependent fracture initiation behavior. The GSPM displays great promise in terms of usability and prediction capacity. It is able to capture the fracture initiation behavior of glass plates of varying geometries exposed to load cases spanning from, e.g., quasi-static four-point bending to blast pressure. The model has the potential to reduce the number of physical experiments and numerical FE simulations in modern development processes of glass structures.

Commentary on “positive family connections: co-producing a virtual group programme for family carers of children with learning disabilities or who are autistic”

PurposeThe purpose of this paper is to provide a commentary on Griffin et al.’s paper, “Positive family connections: Co-producing a virtual group programme for family carers of children with learning disabilities or who are autistic”.Design/methodology/approachThis is a commentary on co-production, drawing on Griffin et al.’s paper and the values base of the field.FindingsCo-production is a valuable approach which seeks to empower and include key people in research. As suggested by Griffin et al., disseminating learning about co-production is an important additional principle of co-production, which demonstrates a values-based commitment to co-production.Originality/valueThis commentary is aimed at professionals and researchers working in the field of learning disabilities who are keen to learn about and do co-production.

Does the Best System Need the Past Hypothesis?

AbstractMany philosophers sympathetic with Humeanism about laws have thought that the fundamental laws will include not only the traditional dynamical equations, but also two additional principles: the Past Hypothesis (PH) and the Statistical Postulate (SP). PH says that the universe began in a particular very-low-entropy macrostate M(0), and SP posits a uniform probability distribution over the microstates compatible with M(0). This view is arguably vindicated by the orthodox Humean Best System Account (BSA). However, I argue that recent developments of the BSA render the Past Hypothesis otiose. In particular, Pragmatic Humeanism does not support the idea that PH is a law.

A composite electrodynamic mechanism to reconcile spatiotemporally resolved exciton transport in quantum dot superlattices.

Quantum dot (QD) solids are promising optoelectronic materials; further advancing their device functionality requires understanding their energy transport mechanisms. The commonly invoked near-field Förster resonance energy transfer (FRET) theory often underestimates the exciton hopping rate in QD solids, yet no consensus exists on the underlying cause. In response, we use time-resolved ultrafast stimulated emission depletion (STED) microscopy, an ultrafast transformation of STED to spatiotemporally resolve exciton diffusion in tellurium-doped cadmium selenide-core/cadmium sulfide-shell QD superlattices. We measure the concomitant time-resolved exciton energy decay due to excitons sampling a heterogeneous energetic landscape within the superlattice. The heterogeneity is quantified by single-particle emission spectroscopy. This powerful multimodal set of observables provides sufficient constraints on a kinetic Monte Carlo simulation of exciton transport to elucidate a composite transport mechanism that includes both near-field FRET and previously neglected far-field emission/reabsorption contributions. Uncovering this mechanism offers a much-needed unified framework in which to characterize transport in QD solids and additional principles for device design.

Scattered beam control of encoded metasurface based on near-field coupling effects of elements

The coupling effect between the element structures of the traditional Huygens metasurface is easy to cause the efficiency of the designed functional devices to be reduced. In order to eliminate or reduce the coupling effect between the element structures, a border-type Huygens metasurface element structure is proposed. In order to confirm that the bounding element structure can significantly reduce the coupling effect, the near-field distribution and far-field properties of two Huygens metasurfaces with and without bounding are compared. Through comparative analysis, we find that the bounding Huygens element structure can significantly reduce the coupling effect between the element structures, and the far-field scattering angle is more consistent with the theoretical calculation value. In order to realize the free regulation of the far-field scattering angle of THz waves, we introduce the Fourier convolution principle in digital signal processing, and operate the element sequence of Huygens metasurface on the addition principle to realize the free regulation of scattered beams. In addition, we performed functional addition operations on the bounding and unbounding coding sequences. The bounding code structure can accurately achieve the synthesis of functions.

A novel thermo‐mechanically coupled material model for glass above the glass transition temperature

AbstractThin glass products have a giant field of application in several engineering branches such as for example, electronics, medical equipment, and the automotive industry. The non‐isothermal glass molding is a novel replicative glass processing technology enabling the realization of a cost‐efficient production of surface shapes with high accuracy and complexity. However, the application of this technology to thin glass production still causes shape distortions, cracks, and surface defects in molded parts. Therefore, these glass‐forming processes should be simulated by means of the combination of experimental investigation and mechanical modeling of glass above the glass transition temperature at finite strains. Previous experimental studies have shown that the Maxwell model is a reasonable approach for an appropriate prediction of the material behavior. Based on this viscoelastic formulation, a thermo‐mechanically consistent material law is used enabling the prediction of rheological effects noticed during the experiments. More specifically, the relaxation behavior can be described by a stress‐dependent relaxation time and the dissipation generated is considered as well. Furthermore, isothermal uniaxial compression tests above the glass transition temperature are conducted for different strain rates and temperatures within the experimental investigation. Combining the experimental data with the simulation, a multi‐curve‐fitting leads to suitable material parameters with respect to distinct temperatures employing a nonlinear optimization.

STATUS UPRAVNIH UGOVORA U PRAVU EU I NACIONALNOM ZAKONODAVSTVU / ADMINISTRATIVE CONTRACTS IN THE LAW OF OBLIGATIONS AND ADMINISTRATIVE PROCEDURE ACT

Directive on the award of concession contracts br. 2014/23/EU, (Official Journal of the EU, L 94/1) ( in further text: Directive 2014/23/EU),Directive on public procurement and repealing Directive 2004/18/EC, br. 2014/24/EU (Official Journal of the EU, L 94/65) (in further text: Directive 2014/24) and Directive on procurement by entities operating in the water, energy, transport and postal services sectors and repealing Directive 2004/17/EC 2014/25/EU Official Journal of the EU, L 94/243) (in further text: Directive 2014/25/EU) arrange relations on the internal EU market by regulating of administrative contracts. Transformation of these Directives in the legal order of Bosnia and Herzegovina can be carried out by appreciating division of obligation and administrative law on general and special part. Namely, administrative contracts cannot be regulated only on the basis of administrative law principles, but law of obligations also. Only in that way can be arranged law of the administrative contracts in the complex legal order in Bosnia and Herzegovina. Such solutions exist in comparative law by containing legal norm that BGB in German or Code civil in Franch law applies accordingly to administrative contracts. Law on obligatory relations basic principles contain legal basis that administrative contracts be regulated in the special part in the Law on obligatory relations. These principles are: participants of obligatory relations; obligatory relations and public resources disposal, obligatory relations and public resources usage, in good faith. Valid principles in the Law on obligatory relations is necessary to supplement with the principles: administrative autonomy of administrative bodies, equal treatment, non-discrimination and transparency. By these additional principles will be developed some principles in the Constitutions of Bosnia and Herzegovina, because regulation tradition in Bosnia and Herzegovina gives such opportunity. Under these principles are assigned norms in EU directives what can be seen in theirs contain, because in this work there is no enough place that for every single principle gives appropriate explanation. Purpose of this work is to initiate new explorations in administrative law. In Bosnia and Herzegovina Law on obligatory relations applies for concluding contracts on concessions and public procurement. They just should become this contract. Because of principles in Law on obligatory relations it is necessary to arrange concluding procedure. By Administrative Procedure Act in institutions of Bosnia and Herzegovina, Federation of Bosnia and Herzegovina and Republika Srpska should be arranged administrative procedure for administrative contract concluding.

Improvement of terahertz beam modulation efficiency for baseless all-dielectric coded gratings

Optical metasurfaces are two-dimensional ultrathin devices based on single-layer or multilayer arrays of subwavelength nanostructures. They can achieve precise control of phase, amplitude, and polarization on the subwavelength scale. In this paper, a substrate-free all-silicon coded grating is designed, which can realize the phase control of the outgoing beam after the y-polarized plane wave is vertically incident on the metasurface at 0.1 THz. Through a single-layer silicon nanoarray structure, a low-reflection anomalous transmission metasurface is realized, and a variety of different beam deflectors are designed based on these encoded gratings. We propose a coded grating addition principle, which adds and subtracts two traditional coded grating sequences to obtain a new coded grating sequence. The encoded supergrating can flexibly control the scattering angle, and the designed substrate-free all-silicon encoded grating can achieve a deflection angle of 48.59°. In order to verify the principle of coded grating addition, we experimented with cascade operation of two coded sequence gratings to obtain the flexible control of the terahertz beam of the composite supergrating. The principle of grating addition provides a new degree of freedom for the flexible regulation of the terahertz wavefront. At the same time, this method can be extended to the optical band or microwave band, opening up new ways for electromagnetic wave manipulation and beam scanning.

Local Assembly in the Orchestral Thinking

The artistically important phenomenon of the temporary separation of ensembles from the orchestral whole, which lasts for a certain structural unit of the composition, is considered. This phenomenon is called "local ensemble". The principles of distinguishing in the existing literature between orchestral solos and soloist ensembles as mainly a group sound effect are defined. The scientific novelty of the study, which stems from a special view of the orchestra as a field of intersection and emergence of instrumental ensembles, is substantiated. A comparative analysis of scores from different eras was carried out in the context of the dynamic opposition "completeness - incompleteness". The additive and subtractive principles of correlation of orchestral integrity with instrument samples are revealed, where the first is formed by adding ensembles that collectively form the orchestra as a result, and the second — by selecting individual ensembles in the orchestra as its temporarily autonomous parts. It was found that despite the presence of orchestral patterns (groups of timbres) and the mention of ensembles of orchestral soloists in previous studies, group ensemble as a structurally separate phenomenon has not yet been sufficiently considered. The effectiveness of using local ensembles to emphasize the architecture of works, to provide an impetus for the active development of drama (introduction to the opera "Parsifal" by R. Wagner) is shown. The simultaneous division of the orchestra into subgroups with different textural and thematic content in the second part of Bach's Brandenburg Concerto No. 2 is analyzed. The phenomenon of "an ensemble outside the general orchestral development" in Gia Kancheli's Sixth Symphony has been revealed. A peculiar phenomenon of the accompanied sequence of local ensembles in the second part of Bartok's Concerto for Orchestra is described. The indirect consequence of local ensemble in scores for a large orchestra is highlighted on the basis of a comparison of orchestral compositions in the works of I. Stravinsky, E. Varese and A. von Webern. It is proven that the local ensemble is a phenomenon of dialectical interaction of the orchestral integrity and its parts, which contributes to the enrichment of orchestral thinking, the demarcation of musical structures, gives impetus to musical-dramatic collisions and the search for new types of orchestra and its functioning.

Coherent chord computation and cross ratio for accurate ellipse detection

This paper presents a new method for detecting ellipses in images, which has many applications in pattern recognition and robotic tasks. Previous approaches typically use sophisticated arc grouping strategies or calculate differential such as tangents, and thereby they are less efficient or more sensitive to noise. In this work, we present a novel ellipse detector, based on the simple yet effective chord computation, and on the projective invariant cross ratio, which achieves promising performance in both accuracy and efficiency. First, elliptical arcs are extracted by fast vector computations along with the removal of straight segments to speed up detection. Then, arcs from the same ellipse are grouped together according to the relative location and the intersecting chord constraints, both are on coherent chord computation without differential. Additionally, an efficient additive principle is applied to further accelerate the grouping process. Finally, a novel and robust verification by area-deduced cross ratio is introduced to pick out salient ellipses. Compared with predecessor methods, cross ratio is not only simple for computation, but also has invariant properties (used to discriminate ellipses). Extensive experiments on seven public datasets (including synthetic and real-world images) are implemented. The results highlight the salient advantages of the proposed method compared to state-of-the-art detectors: Easier to implementation, more robust against occlusion and noise, as well as attaining higher F-measure.

On weak ergodicity breaking in mean-field spin glasses

The weak ergodicity breaking hypothesis postulates that out-of-equilibrium glassy systems lose memory of their initial state despite being unable to reach an equilibrium stationary state. It is a milestone of glass physics, and has provided a lot of insight on the physical properties of glass aging. Despite its undoubted usefulness as a guiding principle, its general validity remains a subject of debate. Here, we present evidence that this hypothesis does not hold for a class of mean-field spin glass models. While most of the qualitative physical picture of aging remains unaffected, our results suggest that some important technical aspects should be revisited.

Identifying a machine-learning structural descriptor linked to the creep behavior of Kob-Andersen glasses

A wide variety of materials, ranging from metals to concrete, experience, typically at high-temperatures or over long time scales, permanent deformations when subjected to sustained loads below their yield stress—a phenomenon known as creep. While theories grounded on defects such as vacancies, dislocations, or grain boundaries can explain creep in crystalline materials, our understanding of creep in disordered solids remains incomplete due to the lack of analogous structural descriptors. In this study, we use molecular dynamics to simulate the creep response of a Kob-Andersen glass model system under constant, uniaxial, compressive stress at finite temperature. We leverage that data to derive, using a machine-learning classification model, a structural descriptor termed looseness, L, which is based on simple and interpretable local structural features and can predict imminent plastic rearrangements within the glass. We show that the average looseness of the system evolves logarithmically with time, mirroring the time dependence of the creep strain and demonstrating the ability of our model to bridge local, short-term particle dynamics with the long-term macroscopic creep response. A detailed feature importance analysis reveals the particular significance of short-range structural heterogeneity in the prediction. We also scrutinize the spatial and temporal correlations of looseness, which mirror the lack of long-range order in glasses and their dynamic heterogeneity. Our research underscores the substantial predictive potential of machine-learning-derived structural indicators in systems experiencing concurrent stress and thermal excitations, paving the way for future work to elucidate the interplay between thermal and mechanical activation of structural defects in disordered solids.

Spectral statistics of a minimal quantum glass model

Glasses have the interesting feature of being neither integrable nor fully chaotic. They thermalize quickly within a subspace but thermalize much more slowly across the full space due to high free energy barriers which partition the configuration space into sectors. Past works have examined the Rosenzweig-Porter (RP) model as a minimal quantum model which transitions from localized to chaotic behavior. In this work we generalize the RP model in such a way that it becomes a minimal model which transitions from glassy to chaotic behavior, which we term the “Block Rosenzweig-Porter” (BRP) model. We calculate the spectral form factors of both models at all timescales larger than the inverse spectral width. Whereas the RP model exhibits a crossover from localized to ergodic behavior at the Thouless timescale, the new BRP model instead crosses over from glassy to fully chaotic behavior, as seen by a change in the steepness of the ramp of the spectral form factor.