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This study aims to optimize the manufacturing process to improve the manufacturing quality, costs and delivering time with the help of multiscale multiphysics modelling and simulation. Multiscale multiphysics-based modelling and simulations are receiving more and more interest by research community and the industry particularly in the context of increasing demands for manufacturing high precision complex products and understanding the intrinsic complexity in associated manufacturing processes.

In this paper, some modelling and analysis techniques using multiscale multiphysics modelling are presented and discussed.

Furthermore, the possibility of adopting the multiscale multiphysics modelling and simulation to develop the virtual machining system is evaluated, and further supported with an industrial case study on abrasive flow machining (AFM) of integrally bladed rotors using the techniques and system developed.

With the development of multiscale multiphysics-based modelling and simulation, it will enable effective and efficient optimisation of manufacturing processes and further improvement of manufacturing quality, costs, delivery time and the overall competitiveness.

The purpose is to analyze the mechanical behavior of the arterial wall in the degraded region of the arterial wall and to determine the stress distribution, as an important factor for predicting the potential failure mechanisms in the wall. In fact, while the collagen fiber degradation process itself is not modeled, zones with reduced collagen fiber content (corresponding to the degradation process) are assumed. To do so, a local weakness in the media layer is considered by defining representative volume elements (RVEs) with different fiber collagen contents in the degraded area to investigate the mechanical response of the arterial wall.

A three-dimensional (3D) large strain hierarchical multiscale technique, based on the homogenization and genetic algorithm (GA), is utilized to numerically model collagen fiber degradation in a typical artery. Determination of material constants for the ground matrix and collagen fibers in the microscale level is performed by the GA. In order to investigate the mechanical degradation, two types of RVEs with different collagen contents in fibers are considered. Each RVE is divided into two parts of noncollagenous matrix and collagen fiber, and the part of collagen fiber is further divided into matrix and collagen fibrils.

The von Mises stress distributions on the inner and outer surfaces of the artery and the influence of collagen fiber degradation on thinning of the arterial wall in the degraded area are thoroughly studied. Comparing the maximum stress values on outer and inner surfaces in the degraded region shows that the inner surface is under higher stress states, which makes it more prone to failure. Furthermore, due to the weakness of the artery in the degraded area, it is concluded that the collagen fiber degradation considerably reduces the wall thickness in the degraded area, leading to an observable local inflation across the degraded artery.

Considering that little attention has been paid to multiscale numerical modeling of collagen fiber degradation, in this paper a 3D large strain hierarchical multiscale technique based on homogenization and GA methods is presented. Therefore, while the collagen fiber degradation process itself is not modeled in this study, zones with reduced collagen fiber content (corresponding to the degradation process) are assumed.

Managers often use positioning models to understand the perceptual structure of markets and make strategic plans. The objective of this paper is to improve strategic planning by suggesting how positioning models can be used to understand, measure, and manage brand uncertainty. A theoretical framework is developed by unifying the results of studies conducted in several disciplines and this framework is used to document the effects of brand uncertainty on brand perceptions and performance. An experiment that empirically establishes the utility of Multiscale in measuring brand uncertainty is designed and conducted. Its results are favorable. A consideration of the limitations of conventional positioning methods leads to the conclusion that, for marketplaces where brand uncertainty exists, such methods provide erroneous and incomplete information. Ways are suggested in which the information provided by Multiscale can be used to improve the breadth and quality of marketing plans.

The purpose of this study is to achieve an accurate intelligent fault diagnosis of rolling bearing.

To extract deep features of the original vibration signal and improve the generalization ability and robustness of the fault diagnosis model, this paper proposes a fault diagnosis method of rolling bearing based on multiscale convolutional neural network (MCNN) and decision fusion. The original vibration signals are normalized and matrixed to form grayscale image samples. In addition, multiscale samples can be achieved by convoluting these samples with different convolution kernels. Subsequently, MCNN is constructed for fault diagnosis. The results of MCNN are put into a data fusion model to obtain comprehensive fault diagnosis results.

The bearing data sets with multiple multivariate time series are used to testify the effectiveness of the proposed method. The proposed model can achieve 99.8% accuracy of fault diagnosis. Based on MCNN and decision fusion, the accuracy can be improved by 0.7%–3.4% compared with other models.

The proposed model can extract deep general features of vibration signals by MCNN and obtained robust fault diagnosis results based on the decision fusion model. For a long time series of vibration signals with noise, the proposed model can still achieve accurate fault diagnosis.

Hydrofracturing technology has been widely used in tight oil and gas reservoir exploitation, and the fracture network formed by fracturing is crucial to determining the resources recovery rate. Due to the complexity of fracture network induced by the random morphology and type of fluid-driven fractures, controlling and optimising its mechanisms is challenging. This paper aims to study the types of multiscale mode I/II fractures, the fluid-driven propagation of multiscale tensile and shear fractures need to be studied.

A dual bilinear cohesive zone model (CZM) based on energy evolution was introduced to detect the initiation and propagation of fluid-driven tensile and shear fractures. The model overcomes the limitations of classical linear fracture mechanics, such as the stress singularity at the fracture tip, and considers the important role of fracture surface behaviour in the shear activation. The bilinear cohesive criterion based on the energy evolution criterion can reflect the formation mechanism of complex fracture networks objectively and accurately. Considering the hydro-mechanical (HM) coupling and leak-off effects, the combined finite element-discrete element-finite volume approach was introduced and implemented successfully, and the results showed that the models considering HM coupling and leak-off effects could form a more complex fracture network. The multiscale (laboratory- and engineering-scale) Mode I/II fractures can be simulated in hydrofracturing process.

Based on the proposed method, the accuracy and applicability of the algorithm were verified by comparing the analytical solution of KGD and PKN models. The effects of different in situ stresses and flow rates on the dynamic propagation of hydraulic fractures at laboratory and engineering scales were investigated. when the ratio of in situ stress is small, the fracture propagation direction is not affected, and the fracture morphology is a cross-type fracture. When the ratio of in situ stress is relatively large, the propagation direction of the fracture is affected by the maximum in situ stress, and it is more inclined to propagate along the direction of the maximum in situ stress, forming double wing-type fractures. Hydrofracturing tensile and shear fractures were identified, and the distribution and number of each type were obtained. There are fewer hydraulic shear fractures than tensile fractures, and shear fractures appear in the initial stage of fracture propagation and then propagate and distribute around the perforation.

The proposed dual bilinear CZM is effective for simulating the types of Mode I/II fractures and seizing the fluid-driven propagation of multiscale tensile and shear fractures. Practical fracturing process involves the multi-type and multiscale fluid-driven fracture propagation. This study introduces general fluid-driven fracture propagation, which can be extended to the fracture propagation analysis of potential fluid fracturing, such as other liquids or supercritical gases.

The purpose of this paper is to assess the progresses made by the Potenza province in implementing #weResilient strategy, a risk-informed sustainable development policy-making action at territorial/local levels based on a structural combination of environmental sustainability, territorial safety and climate change contrasting policies; results obtained in supporting and coordinating the municipalities of the provincial territory for creating local conditions to manage risks and sustainable development with a multiscale and multilevel holistic approach based on a wide-area outlook and so contributing directly to the SFDRR Target E, SDGs 11 and 13 and to other goals and targets; The effectiveness of the accountability system on which the approach is based.

The conceptual basis: A strong governance based on multi-stakeholder and community engagement; The interdisciplinary nature of risk; Enhancing local resilience is an essential pre-condition for achieving all of the SDGs; Downscaling the experience of Potenza Province to the urban context; 10;The design: Description of #weResilient, the multiscale and multilevel approach in Local Resilience and sustainable development adopted by the Province of Potenza: the Vision and institutional commitment; the accountability; the multi-stakeholder engagement; community and people-centered iaction; the achieved results; the critical points. Description and analysis of the performed supportive actions to the municipalities with a subsidiary and wide-area approach.

A significant progress in establishing the basis for a risk-informed decision-making at local level; Further significant progresses in promoting inclusive Resilience across the provincial territory; Progress in Implementation of the Sendai Framework for Disaster Risk Reduction and disaster risk-informed Sustainable Development at local level, including in support of the 2030 Agenda, the Paris Agreement and the New Urban Agenda. Achievements and progresses made in local communities engagement; Achievements in performing actions for including communities and people in relevant institutional decision making processes, building capacities, developing capabilities, raising awareness, increasing political will and public support in local disaster risk reduction and achievement of the SDGs.

The paper is a field-testing of the implementation results of the #weResilient strategy, a risk-informed sustainable development policy-making action at territorial/local levels based on a structural combination of environmental sustainability, territorial safety and climate change contrasting policies; of the coherence of the multiscale and multilevel approach in integrating risk informed and sustainable development pathways; of the improved governance at urban level thanks to the downscaling of the strategy.

Transforming DRR and Resilience to disasters into real “structural” policy-making and actions to be implemented by coordinating territorial and urban development and land-use, with a wide area vision and holistic approach is crucial for the effectiveness of the territorial sustainable development. Moreover, participatory mechanisms can boost althe political will and consequently the related public support. The bottom-up approaches, especially when structured on well defined and clear strategies and supported by concrete actions, are a strategic tool for enhancing the institutional commitment and for enriching the implementation paths also with additional and innovative strategic solution.

In the #weResilient strategy implementation most of the efforts have been devoted to setting-up a complex system of progressive engagement having the main purpose of entrusting and engaging key-actors and community in the institutional policy-making regarding territorial and urban sustainable and resilient development. Engaging community in decision-making processes allows governments to tap into wider perspectives and potential solutions to improve decisions, services and actions. At the same time, it provides the basis for productive relationships, improved dialogue, increased sense of belonging and, ultimately, concrete better democracy.

Multiscale and multilevel holistic approaches in downscaling local well defined Resilience and Sustainable Development integrated strategies (#weResilient) provide for the best approach in terms of future growth. Setting a vision, outlining a strategy and implementing actions on those elements with multiscale and holistic approaches is key- success of every local long-term development; various worldwide leading experiences demonstrated by particularly shining governments are a tangible proof of it. So, the value of this work is to illustrate a concrete example of translation of words into actions so to provide guidance and inspiration to other worldwide governments in performing similar path.

This paper aims to extend the hybrid atomistic-continuum multiscale method developed by Vu et al. (2016) to study the gas flow problems in long microchannels involving density variations.

The simulation domain is decomposed into three regions: the bulk where the continuous Navier–Stokes and energy equations are solved, the neighbourhood of the wall simulated by molecular dynamics and the overlap region which connects the macroscopic variables (density, velocity and temperature) between the two former regions. For the simulation of long micro/nanochannels, a strategy with multiple molecular blocks all along the fluid/solid interface is adopted to capture accurately the macroscopic velocity and temperature variations.

The validity of the hybrid method is shown by comparisons with a simplified analytical model in the molecular region. Applications to compressible and condensation problems are also presented, and the results are discussed.

The hybrid method proposed in this paper allows cost-effective computer simulations of large-scale problems with an accurate modelling of the transfers at small scales (velocity slip, temperature jump, thin condensation films, etc.).

Granular materials possess multiscale structures, i.e. micro-scales involving atoms and molecules in a solid particle, meso-scales involving individual particles and their correlated structure, and macroscopic assembly. Strong and abundant dissipations are exhibited due to mesoscopic unsteady motion of individual grains, and evolution of underlying structures (e.g. force chains, vortex, etc.), which defines the key differences between granular materials and ordinary objects. The purpose of this paper is to introduce the major studies have been conducted in recent two decades.

The main properties at individual scale are introduced, including the coordination number, pair-correlation function, force and mean stress distribution functions, and the dynamic correlation function. The relationship between meso- and macro-scales is analyzed, such as between contact force and stress, the elastic modulus, and bulk friction in granular flows. At macroscales, conventional engineering models (i.e. elasto-plastic and hypo-plastic ones) are introduced. In particular, the so-called granular hydrodynamics theory, derived from thermodynamics principles, is explained.

On the basis of recent study the authors conducted, the multiscales (both spatial and temporal) in granular materials are first explained, and a multiscale framework is presented for the mechanics of granular materials.

It would provide a paramount view on the multiscale studies of granular materials.

Flood season in our country is characterized by frequent heavy rains, and flood problems are becoming increasingly serious. The uneven distribution of water resources causes conflicts in the occurrence of floods and droughts. Implementing effective flood control planning and solving drought and flood disasters are the research highlights of relevant institutions both domestic and abroad. This study develops a multiscale method of urban flood control planning based on microcirculation. A microcirculation water ecosystem, which consists of six elements, namely, collecting, interacting, precipitating, reserving, storing, and purifying, is introduced. This study investigates precipitation; peak shaving; recycle mode of filtration at the macro level in different regions; “hierarchy” in rainwater ecosystems in rain parks, heavy rain garden parks, and wetland parks at the meso level; and the concept of zero-emission rain in residential areas and roads at the micro level. Finally, this study analyzes a rain garden and its domestic application. A conclusion is drawn that the flood control planning model based on microcirculation can effectively reduce rain runoff. Empirical measurement proves that the proposed multiscale model for city flood control planning based on microcirculation promotes flood control and effectively reduces the occurrence of droughts and floods.

This paper aims to introduce a multiscale computational method for structural failure analysis with inheriting simulation of moving trans-scale boundary (MTB). This method is motivated from the error in domain bridging caused by cross-scale damage evolution, which is common in structural failure induced by damage accumulation.

Within the method, vulnerable regions with high stress level are described by continuum damage mechanics, while elastic structural theory is sufficient for the rest, dividing the structural model into two scale domains. The two domains are bridged to generate mixed dimensional finite element equation of the whole system. Inheriting simulation is developed to make the computation of MTB sustainable.

Numerical tests of a notched three-point bending beam and a steel frame show that this MTB method can improve efficiency and ensure accuracy while capturing the effect of material damage on deterioration of components and structure.

The proposed MTB method with inheriting simulation is an extension of multiscale simulation to structural failure analysis. Most importantly, it can deal with cross-scale damage evolution and improve computation efficiency significantly.