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The purpose of this chapter is to optimize multi-criteria formulation for green vehicle routing problems by mixed integer programming. This research is about the road freight transportation of a Spanish company of groceries. This company has more power in the north of Spain and hence it was founded there. The data used for the computational experiments are focused in the northern region of Spain. The data have been used to decide the best route in order to obtain a minimization of costs for the company. The problem focused on the distance traveled and the altitude difference; by studying these parameters, the best solution of route transportation has been made. The software used to solve this model is CPLEX solver with AMPL programming language. This has been helpful to obtain the results for the research and some conclusions have been obtained from them.

The theoretical framework guiding these studies draws from the work of Paulo Freire (1989) who argues that transformation in schools and in society is possible when teachers value and utilize the diverse cultural schema of every student. Our work is further informed by critiques of the deficit perspective that dominates many school settings (Bartolomé & Balderrama, 2001; Garcia, 2001) in the United States. According to this perspective, the documented lack of school success of many children of color, of many children whose first language is not English, and of poor children in general is attributed to deficits in the children themselves, their families, and cultures. Most often, parents are cited for not reading to their children, not emphasizing the importance of education, not disciplining their children, not speaking English to their children, and/or for their own “dysfunctions” which interfere with their children’s learning.

Given the considerable interest currently in the field of early childhood on ways culture influences children’s development, in this chapter I present findings from an ethnographic study I conducted over a six-month period that looks at cultural influences on children’s development. The study looks at 20 Mexican-American children living in a low-income neighborhood in a South Texas community. The children and their families were studied in three specific settings: the children’s homes, the neighborhood surrounding the children’s homes, and the Head Start Center the children attended which was located in the neighborhood. The children ranged in age from 3 to 5 years. Research methodology involved participant observation, informal interviewing, formal interviewing, and document analysis. The theories of Bronfenbrenner and Ogbu provide the framework for considering the cultural perspective in looking at children’s development. Numerous possible themes of cultural aspects as uniquely influencing children’s development emerged from the study’s data collection. The theme I address in this chapter is the adults’ use of names when addressing children. The findings of the study are also compared to the criterion of cultural diversity in Developmentally Appropriate Practice in Early Childhood Programs (Bredekamp & Copple, 1997). Implications for future research and early childhood practice are also presented. Finally, I suggest a new metaphor for looking at culture and its influence on child development.

Due to the increasing size and complexity of construction projects, construction engineering and management involves the coordination of many complex and dynamic processes and relies on the analysis of uncertain, imprecise and incomplete information, including subjective and linguistically expressed information. Various modelling and computing techniques have been used by construction researchers and applied to practical construction problems in order to overcome these challenges, including fuzzy hybrid techniques. Fuzzy hybrid techniques combine the human-like reasoning capabilities of fuzzy logic with the capabilities of other techniques, such as optimization, machine learning, multi-criteria decision-making (MCDM) and simulation, to capitalise on their strengths and overcome their limitations. Based on a review of construction literature, this chapter identifies the most common types of fuzzy hybrid techniques applied to construction problems and reviews selected papers in each category of fuzzy hybrid technique to illustrate their capabilities for addressing construction challenges. Finally, this chapter discusses areas for future development of fuzzy hybrid techniques that will increase their capabilities for solving construction-related problems. The contributions of this chapter are threefold: (1) the limitations of some standard techniques for solving construction problems are discussed, as are the ways that fuzzy methods have been hybridized with these techniques in order to address their limitations; (2) a review of existing applications of fuzzy hybrid techniques in construction is provided in order to illustrate the capabilities of these techniques for solving a variety of construction problems and (3) potential improvements in each category of fuzzy hybrid technique in construction are provided, as areas for future research.

The growing displacement of theory and other forms of wide-ranging knowledge of social phenomena by empirical research methods in economics is widely noted by economists and historians of economic knowledge. Less attention has been devoted, however, to understand the materialization of such changes in the scientific practices. This article studies the recent transformations in the epistemological practices at CEDE, a research center in Colombia. I use a machine learning technique called Topic Modeling, interviews to CEDE researchers, and exegesis of papers to characterize a shift in the production of knowledge in microeconometrics at CEDE during the years 2000 and 2018. I explain this shift by characterizing two sets of epistemological practices that implies a recent tendency to disdain research that cannot make a “strong” causal inference.

The main goal of the paper is to explore the origins and developments of the first community cellular network in Mexico.

Data were gathered in 2015 and 2016 through in-depth interviews, participant observation, workshops, photos, official documents, and informal interviews in the state of Oaxaca in southern Mexico. Data was also drawn from the work of two activists, P. Bloom and E. Huerta, working with the community assemblies of a number of Indígena communities: Villa Talea de Castro, Santa María Yaviche, San Juan Yaee, San Ildefonso Villa Alta, San Bernardo Mixetepec, Santa Ana Tlahuitoltepec, San Jerónimo Progreso, Santiago Ayuquililla, San Miguel Huautla, Santa Inés de Zaragoza, Santo Domingo Xagacia, San Pablo Yaganiza, San Pedro Cajonos, San Francisco Cajonos, San Miguel Cajonos, San Mateo Cajonos, Santa María Alotepec, and San Juan Tabaá. To analyze the data, using codes created in Atlas.TI and relying on an inductive approach, we analyzed the history of this network within a theoretical framework informed by Actor-Network Theory.

Participants in the enactment of this cellular network followed two programs of actions, one technical and one legal. Together, the community assemblies and activists took advantage of available devices, free software and ordinary computers, on the one hand, and communal rules, national laws, constitutional reforms and tacit knowledge, on the other hand. They brought about a new, non-profit, communitarian, and self-organized network that allows for inexpensive communication between members of small, marginalized Indígena communities in the state of Oaxaca in Mexico.

The arrangement of actants that the case illustrates is replicable in other parts of the country and outside of Mexico. The new community cellular network reduces the economic costs of communication, facilitates some jobs and family bonds, expands the range of community-owned projects, encourages self-organization and ways of situated conflict resolution, and empowers communities in relation to external powerful telecommunication corporations.

This is a novel account of a highly unusual set of community-led institutional innovations based on firsthand information drawn from the main actants of the new network.