A SPANWISE rotating cylinder placed at a suitable location in an aerofoil with the cylinder's upper surface moving rearwards in the direction of the local air flow can serve to…
Abstract
A SPANWISE rotating cylinder placed at a suitable location in an aerofoil with the cylinder's upper surface moving rearwards in the direction of the local air flow can serve to re‐energize the boundary layer on the aerofoil. For example, when placed between a flap and a wing with the cylinder protruding substantially into the air flow as shown schematically in no. 1, the moving surface of the cylinder destroys, by viscous shear action, the low‐energy boundary layer impinging on the cylinder from the wing and results in a new boundary layer on the flap's upper surface which has a higher energy level adequate to negotiate the adverse pressure gradients and flow conditions existing at the rear of a flap deflected through a large angle. The boundary layer re‐energizing function of the cylinder depends on its upward protrusion, on its peripheral speed, and on the local flap geometry. The beneficial effects of the rotating cylinder on the flow fields have been visualized in two dimensional smoke studies conducted by Alvarez Caldcrón and Arnold of Stanford University on a flap designed for deflected slipstream V/S.T.O.L. aircraft. Fig. 2 shows flow around the flap with the cylinder stationary. It exhibits complete flow separation at the flap which is also typical of a slotted flap deflected through a large angle. The large white disk is a cylinder end plate; the actual cylinder appears in the darker circular shade of small diameter. The photograph of FIG. 3 was taken with the cylinder rotating: it shows a radical flow change not only in the total elimination of flow separation on the flap but in the induction of strong upwash fields and low pressure regions toward the leading edge of wing itself which obviously greatly increases lift and decreases wing pitching moments.
Many neo-Weberians adopt the state’s authority-monopolizing aim as their theoretical expectation. Through a case study of the Peruvian state and Lima’s squatter settlements, I…
Abstract
Many neo-Weberians adopt the state’s authority-monopolizing aim as their theoretical expectation. Through a case study of the Peruvian state and Lima’s squatter settlements, I provide evidence in support of the opposite contention: that states may unintentionally produce non-state extractive-coercive organizations. During the mid- to late-twentieth century, Lima’s population grew rapidly. Since they had few economic resources, the new urban poor requisitioned public lands and set up dozens of squatter settlements in the city’s periphery. Other researchers have identified several novel political phenomena stemming from such urban conditions. I focus here on the impact of the state. Using secondary and primary data, I examine three periods during which the state applied distinct settlement policies and one in which it did not apply a settlement policy, from 1948 to 1980. I find that when it applied each of the settlement policies, the state produced non-state political authorities – neighborhood elites – who extracted resources from squatters and tried to control neighborhood turf even against state encroachment, and that the state’s non-involvement did not produce them.
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Flavio Morales-Ríos, Aldo Alvarez-Risco, Sarahit Castillo-Benancio, Maria de las Mercedes Anderson-Seminario, Shyla Del-Aguila-Arcentales and Marc A. Rosen
Latin American countries must prioritize energy efficiency and renewable energies in their energy policies. This has been debated for the past few decades. However, it is…
Abstract
Latin American countries must prioritize energy efficiency and renewable energies in their energy policies. This has been debated for the past few decades. However, it is impossible to deny that energy efficiency and renewable energies have significant potential to mitigate the adverse effects of ever-increasing energy consumption induced by economic growth and the transformation of societies toward more energy-intensive models. This chapter identifies how sustainable energy policies could be considered successful in various Latin American economies through an active review and comparison of traditional energy models and their transition and respective consequences. The chapter concludes that there are national energy plans in countries in the region with a sustainable approach, and that clean energy and renewable sources have great potential. But it is also concluded that there is still a long way to go concerning legislation and legal frameworks.
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Mariana Zerón Félix, Claudia Milena Álvarez Giraldo and Cristian Alejandro Rubalcava de León
The objective of this study is to review the main studies of social entrepreneurship (SE) in Latin America, to categorize them into four categories. To accomplish this, a…
Abstract
The objective of this study is to review the main studies of social entrepreneurship (SE) in Latin America, to categorize them into four categories. To accomplish this, a bibliometric literature review is carried out based on data from the Web of Science database, to locate the Latin American collection of studies. In this way, the main studies are described and grouped, following a qualitative scheme that allows to substantiate the main findings of the Latin authors. Consequently, the progress made in the literature of the SE for Latin America is corroborated, by visualizing that the SE turns out to be a forceful fact to manage well-being, but that it is faced with an inconsistent development.
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The purpose of this paper is to challenge the default portrayal of street trade as an informal occupation and spatial practice, by examining comparatively the changes in the…
Abstract
Purpose
The purpose of this paper is to challenge the default portrayal of street trade as an informal occupation and spatial practice, by examining comparatively the changes in the regulatory frameworks of two politically distinct city administrations in Latin America since the introduction of the informal economy debate.
Design/methodology/approach
This paper draws from a comparative case study design to synthesize evidence from historical administrative records, secondary research and materials from a two-year fieldwork carried out in Lima and Bogotá in 2008 and 2009.
Findings
The author argues that the incorporation of the informal economy framework into local governments’ policymaking has reframed street trade as a subject of policy. Since the 1970s, the author traces a shift from worker-centered initiatives, through the deregulation of street trade, to entrepreneurial-centered approaches. Nowadays, both, Lima’s neoliberal governance focusing on “formalizing” and Bogotá’s socialist/progressive governance aiming at “upgrading” street trade respond more explicitly to distinct assessments about the informal economy – legalist and dualist, respectively. Yet, both cities converge in that the closer street trade is perceived as an informal occupation; the more likely policy initiatives decouple the right to work from the right to access public space, spurring more marginal forms of street vending.
Originality/value
Even though the informal economy framework has helped to draw attention to important policy issues locally, nationally and internationally, this paper calls for a critical revision of such framing at the local level to allow for inclusive urban governance.
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Ernesto Tavoletti and Vas Taras
This study aims to offer a bibliometric analysis of the already substantial and growing literature on global virtual teams (GVTs).
Abstract
Purpose
This study aims to offer a bibliometric analysis of the already substantial and growing literature on global virtual teams (GVTs).
Design/methodology/approach
Using a systematic literature review approach, it identifies all articles in the Web of Science from 1999 to 2021 that include the term GVTs (in the title, the abstract or keywords) and finds 175 articles. The VOSviewer software was applied to analyze the bibliometric data.
Findings
The analysis revealed three dialogizing research clusters in the GVTs literature: a pioneering management information systems and organizational cluster, a general management cluster and a growing international management and behavioural studies cluster. Furthermore, it highlights the most cited articles, authors, journals and nations, and the network of strong and weak links regarding co-authorships and co-citations. Additionally, this study shows a change in research patterns regarding topics, journals and disciplinary approaches from 1999 to 2021. Finally, the analysis illustrates the position and centrality in the network of the most relevant actors.
Practical implications
The findings can guide management practitioners, educators and researchers to the most meaningful clusters of publications on GVTs, and help navigate and make sense of the vast body of the available literature. The importance of GVTs has been growing in the past two decades, and Covid-19 has accelerated the trend.
Originality/value
This study provides an updated and comprehensive systematic literature review on GVTs. To the best of the authors’ knowledge, it is also the first systematic literature review and bibliometry on GVTs. It concludes by suggesting future research paths.