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To present a method of interaction between flight loads that is applied to a probabilistic damage tolerance analysis in an acrobatic aircraft.

The uncertainties concerning material strength, initial crack size and loads in the aircraft are considered. We place special emphasis on stress distribution, using superposition criteria that distinguish between gust, maneuver and ground‐air‐ground loads. Gust load is generated form its power spectral density and modified using service load data (exceedance curves). Crack initiation time and propagation time are considered in calculating the service time.

A new and realistic method of interaction between loads during acrobatic flight is proposed. This method was compared with other methods in an example. The effects of the interaction criteria are related to the influence between loads (stress levels and frequency).

In commercial aircraft, maneuver loads have a lower influence than gust loads, and the mission concept is the correct approach. Training aircraft have the opposite king of behavior and the proposed superposition method is shown to be better approach. This method would have more pronounced effects in aircraft types with behaviors between commercial and training (for example, amphibious aircraft).

To make easier the estimation of maintenance cost of airframes, using commercial software and considering reliability's conditions.

It was possible to propose a new method using commercial reliability software. Stress load is included as a random variable in reliability analysis. An example is done. The results are compared with other works.

It is easier and faster to apply than the methodology proposed by other authors.

This paper suggests an easy way of evaluating the economic life of aircraft structures. The calculated optimal stress distribution function can be used with commercial reliability software to estimate the crack size population.

Several studies have been made that analyze factors that affect the demand of tourism from several optics. This paper aims to study the factors that determine the demand for tourism in Mexico, through an econometric analysis, by using the Johansen cointegration model (1991) to determine the long-term elasticity between the demand of tourists and the wealth related to its main markets (the USA and Canada) and the relative prices in Mexico and its two main competitors (the Dominican Republic and Costa Rica).

The authors used econometric analysis using Johansen’s cointegration model (1991), using as a dependent variable the demand of tourists from the main countries of origin (the USA and Canada), taking as data the number of tourists by air in the period 1980-2015, according to information from the SIIMT. The independent variables are the relative wealth of the country of origin of the tourists (wealth of the tourist in Mexico concerning the wealth in their country of origin) and the relative prices of the destination country with respect to the country of competition. The source for per capita income and the consumer price index is the World Bank.

The results obtained in this document show that in the long-term the price is a factor of impact in the purchase decision of both markets analyzed. Presenting an elastic demand to the price, which implies that the market is sensitive to the variations of the price of tourist services, opting for the destination that offers better prices, with a higher sensitivity to the price when compared with Costa Rica. Coinciding with previous studies carried out in other tourist destinations, such as in the work of Patsouratis et al. (2005).

The main contribution of this work is to determine the long-term relationship, through a cointegration analysis of Johansen (1991). A methodology that has not been used to perform a competitive analysis between countries. Additionally, the present work uses variables different from those considered in previous works; the dependent variable is the demand of tourists from the main countries of origin (the USA and Canada) and as dependent variables the relative wealth of the country of origin of the tourists (Wealth of the tourist in Mexico with respect to wealth in their country of origin) and the relative prices of the destination country with respect to the country of competition.

The purpose of this paper is to elucidate if there is a loss in bond strength between galvanized steel used as reinforcement, and concrete of water‐to‐cement (w/c) ratio of 0.4 and 0.5, after both types of sample were cured for seven, 21 and 28 days in saturated calcium hydroxide solution, and without curing. The air permeability of the concrete was investigated at the interfacial zone.

Structural low‐carbon steel and galvanized steel were embedded in concrete samples, prepared with Portland cement type I and limestone (calcite 94‐97 percent) aggregates. The bond strength between the concrete and the reinforcing bars was measured by means of pull‐out tests.

In concrete of w/c=0.4 the bond for galvanized steel was 5.4±0.5 MPa, while the bond for black steel was 5.8±0.5 MPa, which is 7 percent higher than bond strength measured for samples with galvanized steel rebars. The bond strength for galvanized steel in concrete with a w/c ratio 0.5 was 5.5±0.6 MPa, which was 9 percent higher than the values obtained for black steel, which was 5.0±1 MPa. The total average bond strength of galvanized steel in concrete of w/c ratio 0.4 (5.4±0.5 MPa) and w/c ratio 0.5 (5.5±0.6 MPa) was very similar. They differed by only 2 percent. No decrease in the air permeability at the interfacial zone concrete/galvanized steel was found due to curing.

This research gives quantitative data on the behavior of galvanized steel used as reinforcing bars in concrete, prepared with limestone aggregates. The results might help to increase the reliability of galvanized reinforcing steel used in infrastructure exposed to very aggressive tropical humid marine environments.

The Mexican economy is characterized by an extensive business fabric and entrepreneurial culture, which contributes to economic development, the social economy, and the proliferation of entrepreneurship. The effects are reflected in the quality of life, in the growth of employment, in the knowledge spillovers, and in the socioeconomic factors. This chapter offers a contextual review of enterprise creation in Mexico and its relationship on development and entrepreneurship. Following the Economic Censuses and National Survey on Productivity and Competitiveness of Micro, Small and Medium Enterprises (ENAPROCE in Spanish), the profile of entrepreneurs in the period 2009–2014 is analyzed. A conceptual contribution is made from the antecedents of the entrepreneurship to evaluate the success factors and determinants that influence the entrepreneurship in the context of Mexico. Within the findings, regions with entrepreneurial culture are precursors of a competitive process and impulse in employment; at the same time, regions with a low level of GDP per capita and low level of development register high rates of new enterprises, most classified as subsistence enterprises.

This paper aims to review the efficient use of economic and social resources to generate income and, at the same time, reduce the concentration of wealth in the 32 states of the Mexican Republic during the period 1990-2015.

Data envelopment analysis with the inclusion of a bad output was used to diagnose the efficiency of Mexican entities, and the Malmquist–Luenberger index was applied to understand how this efficiency evolves.

The results clearly show that only 3 of the 32 units studied generated and distributed wealth efficiently, while the other 29 must increase their level of income and its distribution.

According to the authors’ knowledge, this is the first work that performs a temporal analysis of the efficiency in the generation of Human Development Index using bad outputs and the Malmquist–Luenberger index.

Since the introduction of product certification in the 1980s, fair trade has grown apart from its social justice roots and the focus has steadily shifted away from calls for institutional market reform, corporate accountability, and fair prices, and toward a celebratory embrace of poverty alleviation and income growth through market integration and business partnerships. This paper examines fair trade's narratives of poverty and partnerships, focusing on the brand communication strategies employed by influential fair trade organizations and businesses. These are compared with how fair trade coffee producers in southern Mexico understand and practice partnership, demonstrating some of the ways in which the latter resist narrative framings which position them as entrepreneurial businesspeople first and cooperativistas second. The business partnerships between coffee buyers and producers are highly asymmetrical, and the partnerships that matter most for the Oaxacan coffee farmers are not with global businesses and certifiers, but instead with each other and their producer organizations. These relationships did not originate with fair trade, although, they are, in part, sustained by this system which supports democratically organized producer groups, the sharing of technical and market information, and communal management of the fair trade premium. In contrast to the organizations that certify and market their products, the paper demonstrates how farmers regard their precarious economic circumstances as an issue of social justice to be addressed through increased state support rather than market empowerment. The analytical juxtaposition of farmers' attitudes with fair trade organizational priorities contributes to the expanding literature examining how fair trade policies are experienced on the ground.

This chapter explains why college-educated Latinas, the daughters of working-class Latino immigrant parents, are disproportionately entering the teaching profession in the United States.

This qualitative study relies on secondary statistical data, an analysis of regional trends and 40 in-depth face-to-face interviews with Latina teachers that work in Southern California elementary schools.

Teaching has traditionally been a white woman’s occupation, but it is now the number one career drawing college-educated Latina women, who are entering the teaching profession at greater rates than African Americans or Asian Americans. Current scholarship posits that teaching is a career that resonates with Latina women’s racial-ethnic solidarity and feminine sense of duty to help others. In this chapter, we show how class background is also a key in understanding why the teaching profession has emerged as the top occupational niche for college-educated Latina women. While racial uplift, gender ideals, and family socialization help explain why college-educated Latinas are going into teaching, we add an emphasis on socio-economic class, demographic and structural context, and collectively informed agency.

This study sheds light on the factors that shape upward mobility and career outcomes in white-collar jobs for minority students and second generation Latinas, the children of immigrants.

This chapter offers a sociological analysis that suggests Latina teachers navigate their educational and career choices with collective-informed agency and strong obligations to family members. To best understand why Latina/Chicana college graduates are increasingly concentrated in the teaching profession, we advocate an intersectionalities approach that takes class seriously.

As the deployment of ICT and the Internet especially increases all around the world, the urgency of providing access to the “have-nots” appears at least diminished, with new issues and urgencies at the forefront. However, studies show that even when the best conditions for access are established, not everyone uses their digital devices for the same purposes, even when sharing the same goals, or when participating in the same experiences.

To explore potential explanations of these phenomena, this study examines survey data from students from a private university in Peru regarding their backgrounds and expertise with ICT. We use the twin concepts of social and cultural capital to establish a connection between their larger lifeworld experiences and their use of digital media. For this purpose, we analyze the data using polychoric correlations to explore patterns resulting from self-perception of access and skills, as well as processes related to social capital such as differentiated media use.

Findings indicate that there are differentiated processes of capital accrual using ICTs, but, at the same time, the productive and leisure dimensions of ICT use must be considered.

Based on goal-directed behavior, this study explores the direct effects and the interaction between health and environmental concerns as the main drivers of organic food consumption. Consumer's economic problems are proposed as the main barrier for such behavior from a cost-benefit approach theoretically grounded on decision theory.

Data were collected using the 26,669 European 95.1 wave participants of the Eurobarometer survey. Logistic regression estimates are used to analyze the hypotheses postulated.

The results indicated the significant association of both health and environmental concerns with organic food consumption, as well as the existence of an interactive effect between both consumer goals. As a novel finding, health concern weakens the influence of environmental concern on organic food consumption. Consumer's economic problems harms the expansion of organic food consumption as well as other socio-demographic factors included as control variables.

For the first time, this research explores the interaction effect between health and environmental concerns as antecedents of organic food consumption. The study argues that these consumer goals present differential features in terms of individual importance, feasibility, abstractness and outcome demonstrability, resulting in a prevalence of health over environmental goals for some consumers. The research provides not only novel insights for understanding organic food consumption but also provides additional evidence for practitioners to develop sales strategies and policymakers to formulate policies to guide the promotion of this so desired example of sustainable consumption.