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The purpose of this paper is to present numerical investigations of the flow dynamic characteristics of a 47° Ahmed Body to identify wake flow control strategy leading to drag coefficient reduction, which could be tested later on sport utility vehicles.

This study begins with a mean flow topology description owing to dynamic and spectral analysis of the aerodynamic tensor. Then, the sparse promoting dynamic modal decomposition method is discussed and compared to other modal approaches. This method is then applied on the wall and wake pressure to determine frequencies of the highest energy pressure modes and their transfers to other frequency modes. This analysis is then used to design appropriated feedback flow control strategies.

This dynamic modal decomposition highlights a reduced number of modes at low frequency which drive the flow dynamics. The authors especially notice that the pressure mode at a Strouhal number of 0.22, based on the width between feet, induces aerodynamic losses close to the rear end. Strategy of the proposed control loop enables to dampen the energy of this mode, but it has been transferred to lower frequency mode outside of the selected region of interest.

This analysis and methodology of feedback control shows potential drag reduction with appropriated modal energy transfer management.

As a practical engineering method, earthquake response spectra play an important role in seismic hazard assessment and in seismic design of structures. However, the computing scale and the efficiency of commercial software restricted the solution of complex structures. There is a clear need of developing large-scale and highly efficient finite element procedures for response spectrum analysis.

In this paper, the kernel theories for earthquake response spectra are deduced and the corresponding parallel solution flow via the modal superposition method is presented. Based on the algorithm and the parallel data structure of JAUMIN framework, a parallel finite element (FE) solution module is established. Using the solution procedure on a supercomputer equipped with up to thousands of processors, the correctness and parallel scalability of the algorithm are evaluated via numerical experiments of typical engineering examples.

The results show that the solution module has the same precision as the commercial FE software ANSYS; the maximum solution scale achieves 154 million degrees of freedom (DOFs) with a favorable parallel computing efficiency, going far beyond the computing ability of the commercial FE software.

The solution scale in this paper is very challenging for the large-scale parallel computing of structural dynamics and will promote the dynamic analysis ability of complex facilities greatly.

The purpose of this study is to propose a fast method for predicting flow fields with periodic behavior with verification in the context of a radial turbine to meet the urgent requirement to effectively capture the unsteady flow characteristics in turbomachinery. Aiming at meeting the urgent requirement to effectively capture the unsteady flow characteristics in turbomachinery, a fast method for predicting flow fields with periodic behavior is proposed here, with verification in the context of a radial turbine (RT).

Sparsity-promoting dynamic mode decomposition is used to determine the dominant coherent structures of the unsteady flow for mode selection, and for flow-field prediction, the characteristic parameters including amplitude and frequency are predicted using one-dimensional Gaussian fitting with flow rate and two-dimensional triangulation-based cubic interpolation with both flow rate and rotation speed. The flow field can be rebuilt using the predicted characteristic parameters and the chosen model.

Under single flow-rate variation conditions, the turbine flow field can be recovered using the first seven modes and fitted amplitude modulus and frequency with less than 5% error in the pressure field and less than 9.7% error in the velocity field. For the operating conditions with concurrent flow-rate and rotation-speed fluctuations, the relative error in the anticipated pressure field is likewise within an acceptable range. Compared to traditional numerical simulations, the method requires a lot less time while maintaining the accuracy of the prediction.

It would be challenging and interesting work to extend the current method to nonlinear problems.

The method presented herein provides an effective solution for the fast prediction of unsteady flow fields in the design of turbomachinery.

A flow prediction method based on sparsity-promoting dynamic mode decomposition was proposed and applied into a RT to predict the flow field under various operating conditions (both rotation speed and flow rate change) with reasonable prediction accuracy. Compared with numerical calculations or experiments, the proposed method can greatly reduce time and resource consumption for flow field visualization at design stage. Most of the physics information of the unsteady flow was maintained by reconstructing the flow modes in the prediction method, which may contribute to a deeper understanding of physical mechanisms.

This paper aims to solve the problem that pipes conveying fluid are faced with severe reliability failures under the complicated working environment.

This paper proposes a dynamic reliability and variance-based global sensitivity analysis (GSA) strategy with non-probabilistic convex model for pipes conveying fluid based on the first passage principle failure mechanism. To illustrate the influence of input uncertainty on output uncertainty of non-probability, the main index and the total index of variance-based GSA analysis are used. Furthermore, considering the efficiency of traditional simulation method, an active learning Kriging surrogate model is introduced to estimate the dynamic reliability and GSA indices of the structure system under random vibration.

The variance-based GSA analysis can measure the effect of input variables of convex model on the dynamic reliability, which provides useful reference and guidance for the design and optimization of pipes conveying fluid. For designers, the rankings and values of main and total indices have essential guiding role in engineering practice.

The effectiveness of the proposed method to calculate the dynamic reliability and sensitivity of pipes conveying fluid while ensuring the calculation accuracy and efficiency in the meantime.

Change is an essential business trait. Manufacturing particularly is transforming at an unprecedented pace. Adopting effective management practices, capable of keeping pace with the changing technological environment, is particularly important to success in global markets. Manufacturers employing advanced manufacturing technology (AMT) are often more flexible than their traditional counter‐parts since AMT permits the integration of product design and production processes. Consequently, this synergistic effect facilitates achievement of world‐class manufacturing objectives. Despite obvious advantages, sparse research exists concerning achieving AMT competitive advantages. To incorporate AMT organizationally, management must be cognizant of the requirements for successful AMT implementation. Provides managerial requirements for successfully achieving AMT competitive advantages. Assuming management understands the “how” of doing things right and incorporates the necessary corporate cultural changes to embrace AMT, manufacturing strategic planning can lead the organization towards “what” are the right things to pursue. Therefore, strategic planning is given substantial consideration.

One crucial but sometimes overlooked fact regarding the difference between observation in the cross-section and observation over time must be stated before proceeding further. Tempting though it is to draw conclusions about the dynamics of a process from cross-sectional observations taken as a snapshot of that process, it is a fallacious practice except under a very precise condition that is highly unlikely to obtain in processes of interest to the social scientist. That condition is known as ergodicity.

The purpose of this article is to review and comment on recent and emerging trends in negotiation research, and to highlight the importance of the interactions between various dimensions of negotiation.

Consistent with the behavioral negotiation framework, a two‐level structure is maintained consisting of the contextual characteristics of negotiation, on the one hand, and the negotiators themselves, on the other. The framework is supplemented with updated research, and the influence of culture in negotiation is commented upon – noting its increasing role in negotiator cognition, motivation, attribution, and cooperation. The paper also adds new themes to reflect the recent advancements in negotiation research. In particular, it focuses on the ways in which negotiator effects can mediate and/or moderate contextual effects, as well as the ways in which contextual effects can mediate and/or moderate negotiator effects.

The paper suggests that efforts to integrate the recent developments in negotiation research are necessary and that the behavioral negotiation perspective, due to its simultaneous simplicity and flexibility, is appropriate and effective for incorporating the various streams of negotiation research into a systematic framework. Critically, this framework highlights the dynamic interaction between the two levels and leaves much room for further exploration of these dynamics.

The paper identifies emerging areas of inquiry that can be especially fruitful in helping negotiation scholars to expand more traditional approaches to conflict in bold new ways and open up innovative avenues for thinking about the domain of negotiation. The paper offers a comprehensive model that integrates various dimensions of negotiation and illustrates the interaction among them.

The typical approach of modeling the aerodynamics of an aircraft is to develop a complete database through testing or computational fluid dynamics (CFD). The database will be huge if it has a reasonable resolution and requires an unacceptable CFD effort during the conceptional design. Therefore, this paper aims to reduce the computing effort required via establishing a general aerodynamic model that needs minor parameters.

The model structure was a preconfigured polynomial model, and the parameters were estimated with a recursive method to further reduce the calculation effort. To uniformly disperse the sample points through each step, a unique recursive sampling method based on a Voronoi diagram was presented. In addition, a multivariate orthogonal function approach was used.

A case study of a flying wing aircraft demonstrated that generating a model with acceptable precision (0.01 absolute error or 5% relative error) costs only 1/54 of the cost of creating a database. A series of six degrees of freedom flight simulations shows that the model’s prediction was accurate.

This method proposed a new way to simplify the model and recursive sampling. It is a low-cost way of obtaining high-fidelity models during primary design, allowing for more precise flight dynamics analysis.

The concept of sustainability evokes a multiplicity of meanings, depending on the field. Some authors have criticized the concept for its vagueness. Notwithstanding this criticism, worldwide efforts to meet the sustainable development goals (SDGs) are in progress and are expected to yield results by 2030. This paper aims to addresses two issues and make two primary contributions. First, the concept of sustainability is revisited to develop its integrative understanding. This concept is built on systems thinking – specifically, on the concepts of synergy, emergence, recursion and self-organization. Second, an approach is developed to help determine whether the efforts being made towards the SDGs can be expected to be effective (i.e., whether the world can hope to soon be a system that self-organizes towards sustainability).

Based on the assumption that the SDGs and their respective targets are systemically interrelated, the data on the progress towards the SDGs are correlated and the outcome is analysed.

The emerging pattern of correlations reflected the systemic coherence of the efforts as an indication of self-organization towards sustainability. This pattern also revealed that the efforts are still spotty and that the systemic synergy has not yet taken place. This correlation approach to Brazil is then applied. The data about Brazil’s progress towards the SDGs from the World Bank’s Word Development Indicators (WDI) database are gathered. The outcomes indicated that Brazil as a whole cannot yet be seen as self-organizing system that is evolving towards sustainability.

To enable the calculation of the correlation matrix, the data series were not allowed to have missing values. Some of the WDI data series had many missing values and had to be eliminated. This unfortunately reduced the variability of the original data. In addition, the missing values in the remaining data series had to be calculated by means of interpolation or extrapolation. There are alternative algorithms to perform such functions. The impact of the interpolation and extrapolation of the missing values on the study, as well as the pros and cons of different algorithms, required investigation. It is important to remark that the WDI series was the only global and open data set that aligned with the SDGs.

In Brazil, it is important to maintain the public policies that affect SDG 1-6, but it is necessary to develop policies geared towards SDG 12. Environmental goals also need more public policies (SDGs 14 and 15). To achieve this 2030 Agenda, much effort will be required for SDG 17, which is related to greater synergy through partnerships.

Three qualitatively distinct levels of efforts to sustainability are identified: individual, organizational and world activities. At the individual level, progress regarding sustainability depends on personal attitudes, including the willingness to abandon a self-centred lifestyle in favour of a more cooperative way of living and making decisions, and to embrace a new approach to ethics, which replaces self-interest by self-denial and self-sacrifice (de Raadt & de Raadt, 2014). At the organizational level, a paradox of the need to internalize environmental and social costs into generic strategies and the sustainability strategy that involves core businesses are challenges for systems working towards sustainability. When it comes to global level, in this paper, the authors tried to make a contribution to push forward the frontier of knowledge by proposing an approach to understand whether the progress made towards the SDGs in the past 25 years indicates that the world is, after all, organizing for sustainability (Schwaninger, 2015).