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The purpose of this paper is to determine the reason for the discrepancy in estimated and observed damage caused by fragmenting charges in closed environments.

A series of carefully conducted physical and numerical experiments was conducted. The results were analyzed and compared.

The analysis shows that for fragmenting charges in closed environments, dust plays a far larger role than previously thought, leading to much lower pressures and damage.

In light of these findings, many assumptions and results for fragmenting charges in closed environments need to be reconsidered.

This implies that for a far larger class of problems than previously estimated it is imperative to take into consideration dust production and its effect on the resulting pressures.

This is the first time such a finding has been reported in this context.

This study aims to evaluate blast loads on and the response of submerged structures.

An arbitrary Lagrangian–Eulerian method is developed to model fluid–structure interaction (FSI) problems of close-in underwater explosions (UNDEX). The “fluid” part provides the loads for the structure considers air, water and high explosive materials. The spatial discretization for the fluid domain is performed with a second-order vertex-based finite volume scheme with a tangent of hyperbola interface capturing technique. The temporal discretization is based on explicit Runge–Kutta methods. The structure is described by a large-deformation Lagrangian formulation and discretized via finite elements. First, one-dimensional test cases are given to show that the numerical method is free of mesh movement effects. Thereafter, three-dimensional FSI problems of close-in UNDEX are studied. Finally, the computation of UNDEX near a ship compartment is performed.

The difference in the flow mechanisms between rigid targets and deforming targets is quantified and evaluated.

Cavitation is modeled only approximately and may require further refinement/modeling.

The results demonstrate that the proposed numerical method is accurate, robust and versatile for practical use.

Better design of naval infrastructure [such as bridges, ports, etc.].

To the best of the authors’ knowledge, this study has been conducted for the first time.

A complete CFD design methodology is presented. The main components of this methodology are a general edge‐based compressible/incompressible flow solver; a continuous adjoint formulation for the gradient computations; a steepest descent technique for the change of design variables; evaluation of the gradient of the discretized flow equations with respect to mesh by finite differences; a CAD‐free pseudo‐shell surface parametrization, allowing every point on the surface to be optimized to be used as a design parameter; and a level type scheme for the movement of the interior points. Several examples are included to demonstrate the methodology developed.

A parallel linelet preconditioner has been implemented to accelerate finite element (FE) solvers for incompressible flows when highly anisotropic meshes are used. The convergence of the standard preconditioned conjugate gradient (PCG) solver that is commonly used to solve the discrete pressure equations, greatly deteriorates due to the presence of highly distorted elements, which are of mandatory use for high Reynolds‐number flows. The linelet preconditioner notably accelerates the convergence rate of the PCG solver in such situations, saving an important amount of CPU time. Unlike other more sophisticated preconditioners, parallelization of the linelet preconditioner is almost straighforward. Numerical examples and some comparisons with other preconditioners are presented to demonstrate the performance of the proposed preconditioner.

Science and technology are transforming our world in ways that have not been seen in a long time, and we live in a rapidly changing world. Despite these changes, as citizens of today, we must not lose sight of the reality that these changes even cause crises that must be managed in order to place ourselves in a true working environment that allows us to survive as employees despite these changes. The main objective of this research is to find the relationship between interpersonal competences and teacher performance in a sustainable university. The methodology used was the quantitative, nonexperimental approach, as the variables will not be deliberately manipulated. In order to verify whether or not there was a relationship between these variables, 84 teachers from the Universidad Nacional Santiago Antunez de Mayolo were surveyed to evaluate the variables under study. The results obtained show a direct and significant relationship (Spearman's Rho = 0.731) between the two variables. Through this research, it was possible to determine that teachers who have developed interpersonal competences have a better performance, while in the relationships between interpersonal competences and the dimensions of teacher performance, a positive correlation was obtained.

Chinese began to arrive in Florida at the turn of the 20th century. Currently there are more than fifty thousand Chinese living in Florida. This article provides information resources for scholars and students of Chinese studies, and for people interested in the history of Chinese Americans and Southeast regional studies. It consists of archive papers, books, journal and newspaper articles and Internet resources containing information on Florida and China. The list is arranged by authors’ last names when available.

Communicating the identity of a family business generates positive results in consumer response. The paper aims to understanding how the efficient transmission of family identity can influence consumer behavior is essential for designing family firms' marketing communication strategies.

An experimental study based on the eye-tracking technique was designed to determine how attention to (familiar vs non-familiar) visual stimuli on a website influences consumer recognition of a family firm status and how it influences consumer behavior. A sample of 212 individuals was exposed to (simulated) websites of family and non-family firms in the hospitality industry to capture information about their eye movements and measure visual attention to specific stimuli that communicated family identity.

Visual attention has a direct and positive influence on recognizing family firm's identity (FFI). Through FFI, visual attention has an indirect positive effect on trust in the company and attitude toward the brand (BraAtt). Trust in a firm positively affects purchase intention (PurInt).

It is known that consumers can perceive a FFI; however, there is no study on the sensory mechanisms operating in consumers' perceptions of family identity. The study contributes to understanding how consumers can perceive a FFI. This study proposes a novel method for evaluating consumer responses by transmitting family business identity on digital platforms.

Presents a numerical strategy for the aerodynamic analysis of large buildings, with an application to the simulation of the air flow within a telescope building. The finite element formulation is presented first, and then the methodology followed to obtain significant data from the calculations is described. The quality of the ventilation of the building is defined by the average residence times, and the feasibility of this ventilation by the actions created on the instruments and the general flow pattern.

The purpose of this paper is to determine if the professional information technology (IT) in Puerto Rico has had an impact during the job search process, financial compensation and success in the industry, from the point of view of management, with the emergence of certification.

The design used in this research was the cross‐sectional and not experimental. To analyze the data in this study the authors used descriptive and inferential statistical techniques.

In accordance with the views expressed by managers, IT professionals with experience are more likely to be selected during the recruitment process and achieve success in their industry compared to professional certification or degree. When managers evaluate the compensation of professionals, certification, academic degree or work experience do not significantly affect the attitude of managers.

The research questions were answered based on the views of managers about the phenomenon studied and did not consider the professionals themselves.

The mechanisms for certification are expensive and tend to be time consuming. The results of this study provide practical benefits to IT professionals because they can be used as a reference.

The results of this research provide valuable information to industries, organizations or businesses and IT professionals in Puerto Rico because they may be used as a reference concerning Puerto Rico's IT industry.

The purpose of this paper is to explore whether information and communication technologies (ICTs) can move people from the informal to the formal sector. ICTs being multipurpose technologies can provide people with information about education, employment opportunities and government services that may potentially allow them to migrate to the formal sector.

The model includes variables that researchers have found to contribute to the growth of informality, such as the state of the economy, the impact of excessive taxes, the impact of regulation, the level of poverty and, of course, ICT metrics, specifically access to both cell phones and broadband as the main two mechanisms through which individuals in the informal sector can obtain information. The analysis relies on a multiple indicators and multiple causes statistical model, to evaluate the hard-to-measure informal economy. A panel data set of 170 countries covering a period of five years was used.

It was found that ICTs empower people, but such empowerment is not always positive for society. So, while mobile phones reduce transaction costs of informal business, this leads to their growth, as they are only a coordination technology. The empowerment that comes from broadband, meaning greater and deeper access to information and resources, can help reduce this sector of the economy and potentially improve these individuals’ lives as well.

Measurement of the informal sector is a challenge to researchers precisely because it is hidden. This, like other work in this area, relies on estimates from indirect measures of the informal sector. The results are to be interpreted with caution. In addition, given that this research relies on country-level data, any specific policy decision will have to take particular circumstances into consideration to adapt these results to a specific context.

This study is important because of the more nuanced effect found between narrow and broadband technologies with respect to the informal economy and because of its policy implications. Given the results, governments should consider broadband as an additional tool to help individuals make the transition from the informal to the formal sector.

Once an individual who works in the informal sector begins to realize the advantages of moving to the formal sector, it with the help of ICTs. This awareness could potentially lead to a slow but steady migration away from the informal economy that can improve the economic conditions of the population in these countries.

Scholars up to this point have been quite enthusiastic about the benefits of ICTs. In this paper, it was found that the effects are not always positive; a mobile does not help people move away from poverty and, in fact, supports the informal sector. It was found that only broadband can help these entrepreneurs move into the formal sector.