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The paper aims to describe the results of a recent GridShibPERMIS project whose purpose was to provide policy‐driven role‐based access control decision‐making to grid jobs, in which the user's attributes are provided by an external Shibboleth Identity Provider (IdP).

This was achieved by integrating the identity‐federation and attribute‐assignment functions of Shibboleth and the policy‐based enforcement functions of PERMIS with the Grid job management functions of Globus Toolkit v4.

Combining the three technologies proved to be relatively easy due to the Policy Information Point (PIP) and Policy Decision Point (PDP) Java interfaces recently introduced into Globus Toolkit v4.

However, a number of limitations in the current Grid‐Shib implementation were revealed, namely: the lack of support for pseudonymous access to grid resources; scalability problems because only one issuer scope domain is supported and because name mappings have to be provided for each grid user; and the inability to collect a user's attributes from multiple IdPs for use in authorisation decision‐making.

This paper provides an overview of and describes the benefits of the three technologies (GT4, Shibboleth and PERMIS), shows how they may be combined to good effect via GT4's java interfaces, describes the limitations of the current GridShib implementation and suggests possible solutions and additional research that are needed in the future in order to address the current shortcomings.

The problem of finding the possible classes of solution of different nonlinear equations seems to be of a great importance for many applications. In the context of the theory of self‐organization it is interpreted as finding all possible structures which arise and preserve themselves in the corresponding unbounded nonlinear medium. First, results on the numerical realization of a class of blow‐up invariant solutions of a nonlinear heat‐transfer equation with a source are presented in this article. The solutions considered describe a spiral propagation of the inhomogeneities in the nonlinear heat‐transfer medium. We have found initial perturbations which are good approximations to the corresponding eigen functions of combustion of the nonlinear medium. The local maxima of these initial distributions evolve consistent with the self‐similar law up to times very close to the blow‐up time.

This research examines factors that determine the improvement of the Russian supply chain sustainability. The strategic business model incorporates ecological, social and economic aspects.

Considering Trans-Siberian Railway as a typical case, the study selected several cases or the parts of the primary rail connection with the affiliation of important neighbouring countries. The study uses quantitative analyses of a variety of size parameters (e.g. volumes of traffic, logistics costs, delivery distance and air pollutants).

The empirical findings stress that supply chains should favour in the future railway (or intermodal) connections for piggyback and containerised cargo. Herein lays the reason for the examination of all traditional factors affecting the modal choice and their complementation by the parameters to measure sustainability throughout the supply chains. The inclusion of the green practices positively affected the environmental, social and economic performance of the new approach.

This research focuses on the delivery of cargo in containers and semi-trailers within wagons through the overland corridors. Despite the restrictive empirical findings within the national transport system, some elements can be representative of the international supply chains, provided that intermodal services are the most appropriate for the transportation over long distances.

Clients, media and regulatory bodies stress the consideration of environmental aspects at all stages of a global supply chain. Therefore, their adoption into strategic imperatives of local supply chains becomes inevitable.

An assessment of supply chains for longer distance transportation in Russia has not taken sustainability into account within cost analyses.

The paper aims to identify a suitable generic brake force distribution ratio (β) corresponding to optimal brake design attributes in a diminutive driving range, where road conditions do not exhibit excessive variations. This will intend for an appropriate allocation of brake force distribution (BFD) to provide dynamic stability to the vehicle during braking.

Two techniques are presented (with and without wheel slip) to satisfy both brake stability and performance while accommodating variations in load sharing and road friction coefficient. Based on parametric optimization of the design variables of hydraulic brake using evolutionary algorithm, taking into account both the laden and unladen circumstances simultaneously, this research develops an improved model for computing and simulating the BFD applied to commercial and passenger vehicles.

The optimal parameter values defining the braking system have been identified, resulting in effective β = 0.695 which enhances the brake forces at respective axles. Nominal slip of 3.42% is achieved with maximum deceleration of 5.72 m/s² maintaining directional stability during braking. The results obtained from both the methodologies are juxtaposed and assessed governing the vehicle stability in straight line motion to prevent wheel lock.

Optimization results establish the practicality, efficacy and applicability of the proposed approaches. The findings provide valuable insights for the design and optimization of hydraulic drum brake systems in modern automobiles, which can lead to safer and more efficient braking systems.

The purpose of this paper is to analyse the advantages of a new interpretation of the geometric disposition of threads within woven fabric structures, and to develop a method of determining the parameters of threads, with reference to each order of their disposition.

Based on the analysis of the geometrical models proposed by Barker and Midgely, by Pierce and by Novikov, the substantiation of the advantages of a stricter model, offered by the authors, for determining the geometric disposition of threads within single layer woven fabric structures with the help of the tangent function is given. This model allows the substantial expansion of the actual bounds of the interval of the order of the geometric disposition of threads in woven fabric structures to 0.2‐9.8.

The tangent function can approximate the crimp height ratio of the warp threads within the woven fabric structure with accuracy within the limits of geometric disposition angle change from 1° to 89°.

The work has applications in the industrial production of woven fabrics.

This research will allow the design of a woven fabric with practically any ratio of crimp height for the warp and weft threads to effectively achieve the required performance characteristics of the cloth.

This paper extends the knowledge of the geometrical characteristics of woven fabric structure, and proposes intelligent methods of determining the parameters of thread cross‐sections in accordance with the orders of the geometric disposition of threads in woven fabric structure.

The terrorism of “Islamic State” (IS) is increasingly coming to be seen as a complicated and complex phenomenon permeated with various political goals and personal interests. The effectiveness of terrorist recruiters determines the need to identify the reasons for the appeal of the IS image and for the effectiveness of IS propaganda in different population layers and social groups. From this perspective, it is crucial to identify the significant social factors that are most affecting the perception of the terrorist activities of “IS” and their role in creating and shaping IS images. The purpose of this paper is to determine the role of social capital in the perception of the IS image.

The study is based on the findings of a sociological survey of a sample comprising 881 Russian students. In this research, six scales were used to identify the attitude of Russian students toward IS: informational awareness of IS; the image of IS fighters; the image of IS as an organization; attitude to an anti-terrorist policy; the role of the mass media; the level of social capital. Factorial analysis of the main components was conducted for each of the scales.

Subsequently, the correlation analysis of the relationship of social capital to the perception of the image of “IS” was conducted. Six main IS images were identified in the minds of the students. The research results show that survey participants with high levels of social capital are significantly more negative in their perception of the activities of the terrorist organization in question.

From this perspective, it is crucial to identify the significant social factors that are most affecting the perception of the terrorist activities of “IS” and their role in creating and shaping IS images. This study focuses on determining the role of social capital in the perception of the IS image.

Active employment of additive manufacturing for scaffolds preparation requires the development of advanced methods which can accurately characterize the morphologic structure and its changes during an interaction of the scaffolds with substrate and aqueous medium. This paper aims to use the method of nuclear magnetic resonance (NMR) imaging for preclinical characterization of 3D-printed scaffolds based on novel allyl chitosan biocompatible polymer matrices.

Biocompatible polymer scaffolds were fabricated via stereolithography method. Using NMR imaging the output quality control of the scaffolds was performed. Scaffolds stability, polymer matrix homogeneity, kinetic of swelling processes, water migration pathways within the 3D-printed parts, effect of post-print UV curing on overall scaffolds performance were studied in details.

NMR imaging visualization of water uptake and polymer swelling processes during the interaction of scaffolds with aqueous medium revealed the formation of the fronts within the polymer matrices those dynamics is governed by case I transport (Fickian diffusion) of the water into polymer network. No significant difference was observed in front propagation rates along the polymer layers and across the layers stack. After completing the swelling process, the polymer scaffolds retain their integrity and no internal defects were detected.

NMR imaging revealed that post-print UV curing aimed to improve the overall performance of 3D-printed scaffolds might not provide a better quality of the finish product, as this procedure apparently yield strongly inhomogeneous distribution of polymer crosslink density which results in subsequent inhomogeneity of water ingress and swelling processes, accompanied by stress-related cracks formation inside the scaffolds.

This study introduces a method which can successfully complement the standard tests which now are widely used in either additive manufacturing or scaffolds engineering.

This work can help to improve the overall performance of the polymer scaffolds used in tissue engineering.

The results of this study demonstrate feasibility of NMR imaging for preclinical characterization of 3D printed biocompatible polymer scaffolds. The results are believed to contribute to better understanding of the processes vital for improving the design of 3D-printed polymer scaffolds.

Large eddy simulation (LES) is widely used in prediction of turbulent flow. The purpose of this paper is to propose a new dynamic mixed nonlinear subgrid‐scale (SGS) model (DMNM), in order to improve LES precision of complex turbulent flow, such as flow including separation or rotation.

The SGS stress in DMNM consists of scale‐similarity part and eddy‐viscosity part. The scale‐similarity part is used to describe the energy transfer of scales that are close to the cut‐off explicitly. The eddy‐viscosity part represents energy transfer of the other scales between smaller than grid‐filter size and larger than grid‐filter size. The model is demonstrated through two examples; one is channel flow and another is surface‐mounted cube flow. The computed results are compared with prior experimental data, and the behavior of DMNM is analyzed.

The proposed model has the following characteristics. First, DMNM exhibits significant flexibility in self‐calibration of the model coefficients. Second, it does not require alignment of the principal axes of the SGS stress tensor and the resolved strain rate tensor. Third, since both the rotating part and scale‐similarity part are considered in the new model, flow with rotation and separation is easily simulated. Compared with the prior experimental data, DMNM gives more accurate results in both examples.

The SGS model DMNM proposed in the paper could capture the detail vortex characteristics more accurately. It has the advantage in simulation of complex flow, including more separations.

Construct a new sub-grid scale (SGS) model which can improve the efficiency and maintain comparative accuracy comparing to the existing dynamic cubic non-linear SGS model (DCNM).

The polynomial constitutive relation between the SGS stress tensor and both strain and rotation rate is selected as a basement. Simplification is achieved by eliminating the solid-body rotation term and adopting the assumption proposed by Kosovic. A dynamic procedure is applied to calculate three model coefficients in the new model. The new model (named dynamic simplified Lund model) and DCNM are applied to the rotating channel flow and the internal flow in a centrifugal pump impeller to examine the performance.

The new model is as accurate as DCNM but decreases 25 per cent computational resources. The ability of capturing rotation effect and reflecting backscatter is verified through cases. In addition, good numerical stability is shown during the calculation.

More benchmark and engineering cases should be used to get further confidence on the new model.

The new model is promising in industrial application with the advantage of both accuracy and efficiency. For the flow with large-scale separation or more complicate phenomenon, the model is thought to give accurate flow structure.

A new non-linear SGS model is proposed in this paper. The accuracy, numerical stability and efficiency are validated for this model. Therefore, it is promising in the prediction of the flow structure in centrifugal pumps.

This paper aims to identify key factors influencing the development of advanced manufacturing clusters and propose governance pathways for their digital innovation ecosystems.

A quantitative analysis of the Tai-Xin Integrated Economic Zone in China is conducted using data collected through a questionnaire survey. An evaluation index for the development level of advanced manufacturing clusters is constructed, and a structural equation model is used to identify key influencing factors and governance pathways.

This paper reveals that factors such as industrial foundation, technological innovation capability, social institution environment and government policies have a significant positive impact on the development of digital innovation ecosystem in advanced manufacturing clusters. It constructs a governance model for the digital innovation ecosystem and proposes three major pathways: integration of heterogeneous innovation resources, enhancement of digital capabilities, and fostering digital collaborative governance. The crucial role of digital technology in improving data processing efficiency, optimizing resource allocation and promoting collaboration among entities is emphasized. These pathways can optimize resource allocation, boosting the competitiveness and innovation capacity of clusters.

By incorporating advanced manufacturing clusters into the digital innovation ecosystem framework, this paper enriches theoretical research on both fronts. It offers specific governance pathways and policy recommendations, providing valuable references and guidance for promoting the digital transformation and ecosystem construction of manufacturing clusters.