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The meshfree node-based smoothed point interpolation method (NS-PIM) is extended to the forward and inversion analysis of a high gravelly soil core rock-fill dam during construction periods.

As one member of the meshfree methods, the NS-PIM has the advantages of “softer” stiffness and adaptability to large deformations which is quite indispensable for the stability analysis of rock-fill dams. In this work, the present method contains a reconstruction procedure to deal with the existence or nonexistence of the construction layers. After verifying the validity of the NS-PIM method for nonlinear elastic model during construction period, the convergence features of the NS-PIM and FEM methods are further investigated with different mesh schemes. Furthermore, the NS-PIM and FEM methods are applied for the forward analysis of a high gravelly soil core rock-fill dam and the convergence features under complex stress conditions are also studied using the rock-fill dam model. Finally, the NS-PIM method is used to calculate the Duncan–Chang parameters of the deep overburden under the high gravelly soil core rock-fill dam based on the back-propagation neural network method.

The results show that: the NS-PIM solution for construction analysis still possesses the property of upper bound solution even under complex stress conditions and can provide comparatively more conservative results for safety evaluation. Furthermore, it can be used to evaluate the accuracy of results and mesh quality together with the FEM solution which has the property of lower bound solution; the inversion analysis in this work provides a set of material parameters for the deep overburden under high rock-fill dam during construction period and the calculated results show good agreement with the measured displacement values and it is feasible to apply the NS-PIM to the forward and inversion analysis of high rock-fill dams on deep overburden during construction periods.

In further study, the feasibility of three-dimensional problems, elastic–plastic problems, contact problems and multipoint inversion can still be probed in the NS-PIM solution for the forward and inversion analysis of high rock-fill dams on deep overburden.

This paper introduced a method for the forward and inversion analysis of high rock-fill dams during construction period using the NS-PIM solution. The property of upper bound solution ensures that the NS-PIM can provide more conservative results for safety evaluation. The inversion analysis in this work provides a set of material parameters for the deep overburden under high rock-fill dam during construction periods.

First, the analysis from forward to inversion for high rock-fill dams during construction period using the NS-PIM solution is accomplished in this work. A procedure dealing with the existence or nonexistence of the construction layers is also developed for the construction analysis. Second, it is confirmed in this work that the NS-PIM still possesses the property of upper bound solution even under complex stress conditions (the forward analysis of high rock-fill dams during construction period). Thus, more conservative results can be provided for safety evaluation. Furthermore, it can be used to evaluate the accuracy of results and mesh quality together with the FEM solution which has the property of lower bound solution. Third, the calculated material parameters of the deep overburden in this work can be used for further studies of the high rock-fill dam.

To improve the efficiency, accuracy and adaptivity of the parameter inversion analysis method of a rockfill dam, this study aims to establish an adaptive model based on a harmony search algorithm (HS) and a mixed multi-output relevance vector machine (MMRVM).

By introducing the mixed kernel function, the MMRVM can accurately simulate the nonlinear relationship between the material parameters and dam settlement. Therefore, the finite element method with time consumption can be replaced by the MMRVM. Because of its excellent global search capability, the HS is used to optimize the kernel parameters of the MMRVM and the material parameters of a rockfill dam.

Because the parameters of the HS and the variation range of the MMRVM parameters are relatively fixed, the HS-MMRVM can imbue the inversion analysis with adaptivity; the number of observation points required and the robustness of the HS-MMRVM are analyzed. An application example involving a concrete-faced rockfill dam shows that the HS-MMRVM exhibits high accuracy and high speed in the parameter inversion analysis of static and creep constitutive models.

The applicability of the HS-MMRVM in hydraulic engineering is proved in this paper, which should further validate in inversion problems of other fields.

An adaptive inversion analysis model is established to avoid the parameters of traditional methods that need to be set by humans, which strongly affect the inversion analysis results. By introducing the mixed kernel function, the MMRVM can accurately simulate the nonlinear relationship between the material parameters and dam settlement. To reduce the data dimensions and verify the model’s robustness, the number of observation points required for inversion analysis and the acceptable degree of noise are determined. The confidence interval is built to monitor dam settlement and provide the foundation for dam monitoring and reservoir operation management.

The purpose of this paper is to present a novel strategy used for acceleration of free-vibration analysis, in which the hierarchical matrices structure and Compute Unified Device Architecture (CUDA) platform is applied to improve the performance of the traditional dual reciprocity boundary element method (DRBEM).

The DRBEM is applied in forming integral equation to reduce complexity. In the procedure of optimization computation, ℋ-Matrices are introduced by applying adaptive cross-approximation method. At the same time, this paper proposes a high-efficiency parallel algorithm using CUDA and the counterpart of the serial effective algorithm in ℋ-Matrices for inverse arithmetic operation.

The analysis for free-vibration could achieve impressive time and space efficiency by introducing hierarchical matrices technique. Although the serial algorithm based on ℋ-Matrices could obtain fair performance for complex inversion operation, the CUDA parallel algorithm would further double the efficiency. Without much loss in accuracy according to the examination of the numerical example, the relative error appeared in approximation process can be fixed by increasing degrees of freedoms or introducing certain amount of internal points.

The paper proposes a novel effective strategy to improve computational efficiency and decrease memory consumption of free-vibration problems. ℋ-Matrices structure and parallel operation based on CUDA are introduced in traditional DRBEM.

This work is devoted to the experimental analysis, numerical modelling and validation of ice melting processes.

The thermally coupled incompressible Navier‐Stokes equations including water density inversion and isothermal phase‐change phenomena are assumed as the governing equations of the problem. A fixed‐mesh finite element formulation is proposed for the numerical solution of such model. In particular, this formulation is applied to the analysis of two different transient problems.

The numerical results computed with the finite element formulation have been found to be very similar to the corresponding predictions, also obtained in this study, provided by a finite volume enthalpy‐based technique. Both numerical results, in turn, satisfactorily approached the available experimental measurements expressly conducted in the context of this work for validation purposes.

They are mainly due to some model simplifications (e.g. no volume changes are considered during the solid‐liquid transformation) and to the inherent difficulties associated with the experimental measurements.

This study may be relevant for a better understanding of the phenomena occurring in different engineering applications involving phase‐change in water: food freezing, ice formation in pipes, freezing/melting processes in soils, ice growth in plane wings, etc.

The study is mainly focused on the validation of the numerical predictions obtained with the finite element formulation mentioned above with other results provided by a well‐known finite volume technique and, in addition, with available laboratory measurements carried out in the context of this work.

The orthodox approach in contemporary architectural pedagogy, grounded in a narrowly conceived rationality, lacks diversity in terms of both the population it serves and the methods it follows in the studio. This paper advances a social construction model with distinct advantages over the rational model. Based on multidisciplinary research, the model presented here is experimental, promoting innovation and allowing the unpredictable to emerge. It encourages students and studio clients to create their own collaborative reality. The paper recommends four socially constructive techniques for architecture/community design in neighborhood revitalization. Inversion begins with the client's vision. As students and residents work together to form their own image of the ideal community, the resulting vision informs subsequent data collection and analysis. Simulation allows students and other participants to undertake small-scale experiments, drawing immediate lessons that enhance the final implementation process. Reciprocity involves role-switching between expert partners and non-expert participants to counter biases while building mutual understanding. Finally, with Research in Action, hypothesis testing and design occur simultaneously. With these social construction approaches, predetermined steps in the rational model are reversed, merged, or even omitted. Faculty and expert partners behave more like facilitators than directors, coordinating activities and processes, reinforcing initiatives, and resolving conflicts-as clients make key design decisions. By assigning some major responsibilities to students and residents, social construction creates a sense of ownership among stakeholders. The paper compares the rational and social construction approaches, discussing implications and suggesting areas of further study.

To demonstrate the improvement of three‐axial magnetic sensors systems for magnetocardiography when using minimum norm solutions (MNS).

The thesis is proved by using figures of merit and by means of repeated numerical simulations, starting from a BEM model for forward calculations.

We found out that both for under‐determined and over‐determined problems two figures of merit show better performance of a three‐axial sensor system when compared with two mono‐axial sensor systems. We also showed the positive impact of three component magnetic field data on MNS by means of repeated simulations.

The analysis is limited to theoretical sensor systems and can be applied also to realistic measurement set‐ups. Noise is considered uncorrelated. The analysis could be carried out with the help of other figures of merit. More refined models for the human body could be adopted.

The use of three axial sensor systems is encouraged in the field of magnetocardiography.

Numerical analysis of inversion algorithms using three‐dimensional magnetic field data in magnetocardiography have been never carried out.

Parameter identification is an important issue in structural health monitoring and damage identification for concrete dams. The purpose of this paper is to introduce a novel adaptive fireworks algorithm (AFWA) into inverse analysis of parameter identification.

Swarm intelligence algorithms and finite element analysis are integrated to identify parameters of hydraulic structures. Three swarm intelligence algorithms: AFWA, standard particle swarm optimization (SPSO) and artificial bee colony algorithm (ABC) are adopted to make a comparative study. These algorithms are introduced briefly and then tested by four standard benchmark functions. Inverse analysis methods based on AFWA, SPSO and ABC are adopted to identify Young’s modulus of a concrete gravity dam and a concrete arch dam.

Numerical results show that swarm intelligence algorithms are powerful tools for parameter identification of concrete structures. The proposed AFWA-based inverse analysis algorithm for concrete dams is promising in terms of accuracy and efficiency.

Fireworks algorithm is applied for inverse analysis of hydraulic structures for the first time, and the problem of parameter selection in AFWA is studied.

The buried pipe element method can be used to calculate the temperature of mass concrete through highly efficient computing. However, in this method, temperatures along cooling pipes and the convection coefficient of the cooling pipe boundary should be improved to achieve higher accuracy. Thus, there is a need to propose a method for improvement.

According to the principle of heat balance and the temperature gradient characteristics of concrete around cooling pipes, a method to calculate the water temperature along cooling pipes using the buried pipe element method is proposed in this study. By comparing the results of a discrete algorithm and the buried pipe element method, it was discovered that the convection coefficient of the cooling pipe boundary for the buried pipe element method is only related to the thermal conductivity of concrete; therefore, it can be calculated by inverse analysis.

The results show that the buried pipe element method can achieve the same accuracy as the discrete method and simulate the temperature field of mass concrete with cooling pipes efficiently and accurately.

This new method can improve the calculation accuracy of the embedded element method and make the calculation results more reasonable and reliable.

This paper aims at the problem of surrounding rock excavation damage zone of tunneling in the rich water region, this paper aims to propose a new seepage-stress-damage coupling model and studied the numerical algorithm. This reflects the characteristics of rock damage evolution, accompanied by plastic flow deformation and multi-field interaction.

First of all, rock elastoplastic damage constitutive model based on the Drucker–Prager criterion is established, the fully implicit return mapping algorithm is adopted to realize the numerical solution. Second, based on the relation between damage variation and permeability coefficient, the rock stress-seepage-damage model and multi-field coupling solving iterative method are presented. Finally, using the C++ language compiled the corresponding programs and simulated tunnel engineering in the rich water region.

Results show that difference evolution-based back analysis inversed damage parameters well, at the same time the established coupling model and calculating program have more advantages than general conventional methods. Multiple field coupling effects should be more considered for the design of tunnel support.

The proposed method provides an effective numerical simulation method for the construction of the tunnel and other geotechnical engineering involved underground water problems.

Purpose – To examine debates within the transgender rights movement over the GID diagnosis in order to demonstrate how diagnosis can be resisted as a source of stigma and social control at the same time that it is embraced as a means of legitimating experience and gaining access to resources, including medical services.

Methodology/approach – This chapter draws on qualitative data from: in-depth interviews with transgender rights activists and advocates, participant observation in transgender health care and activism settings, and content analysis of print and web-based materials on transgender health.

Findings – Transgender rights activists and advocates overwhelmingly reject the pathologization of gender variance. However, some actors advocate complete demedicalization, while others advocate diagnostic reform. Actors' advocacy for each position is influenced by the perceived costs versus benefits of diagnosis.

Social implications – The findings of this research shed light on the multiple and often contradictory effects of diagnosis. Diagnoses can both normalize and stigmatize. They can function to allow or deny access to medical services and they can support or act as barriers to legal rights and protections. Understanding these contradictory effects is essential to understanding contests over diagnosis, including the contemporary debate over GID.

Originality/value of paper – Through examination of an intra-constituent contest over diagnosis, this research demonstrates the need to distinguish medicalization from pathologization and illustrates the importance of examining the multiple and contradictory effects of diagnosis, both in and outside of medical settings.