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This article aims to explore the impact of a particular regulatory framework for CDMA and GSM use by fixed‐phone companies in Brazil on access, local‐loop competition and fixed‐mobile convergence.

The paper is based on the analysis of the three most significant cases in Brazil and the discussion of recent regulatory changes that facilitate access to radio spectrum on a secondary basis.

Among the findings of the study is that while fixed‐wireless access (FWA) systems using CDMA seem to be more suitable to high‐density, well‐served areas, in which a large operator attempts to address a low‐income market satisfied with restricted mobility – GSM systems deployed on a secondary basis are best fitted to address the digital gap in low‐income, underserved areas, promoting local‐loop competition in markets of little interest to traditional operators.

The conclusion outlines regulatory recommendations for promoting competition and the growth of innovative, small‐scale operators that take advantage of new wireless technologies to address service coverage gaps.

The paper presents the first attempt to address the Brazilian CDMA‐ and GSM‐based fixed wireless access experience from a regulatory perspective and analyzes the “ruralfone” case, which uses a fixed phone license to deliver GSM‐based services in underserved communities, surpassing incumbent penetration in cities where there is no cellular network yet under a given regulatory environment in Brazil.

Profiles broadband communications, wondering whether AOL Time Warner will keep its side of the bargain that promises to provide a universal telephone service, in exchange for accepting regulations regarding monopoly. Recommends that only by quality of service monitoring can AOL Time Warner be seen to be keeping its side of the bargain. Concludes that quality of service monitoring is a timely approach in the USA with regard to broadband communications systems.

The purpose of this paper is to verify whether the horizontal grab bar for the toilet and the bathtub suggested by the Code du bâtiment du Québec conform to users’ preferences. Perceived effort, comfort and safety were considered.

In total, 31 adults and seniors using manual and powered wheelchairs were asked to test different grab bar configurations for both the toilet and bathtub. A questionnaire was designed to evaluate participants’ perceptions and preferences after the trials with each grab bar. Effort was measured using the ten-level Borg scale, while participants’ comfort and safety were assessed with a five-point Likert scale. Participants were finally invited to express an overall personal preference between the two grab bar used in each setup.

Participants showed preference for an L-shaped grab bar for the toilet, and a horizontal grab bar for the bathtub. The authors’ results differ from the recommendations of the barrier-free design standards of the province of Quebec’s construction code, which states that horizontal grab bars should be used for the toilet and bathtub.

This study suggest that despite the limited sample, there is an undeniable need for testing norms for public spaces, whenever is possible and has a direct effect on end-users, before publishing them.

Existing deterministic models that predict the capacity of corroded reinforced concrete (RC) beams have limited applicability because they were based on accelerated tests that induce general corrosion. This research gap was addressed by performing a combined numerical and statistical analysis on RC beams, subjected to natural corrosion, to achieve a much better forecast.

Data of 42 naturally corroded beams were collected from the literature and analyzed numerically. Four constitutive models and their combinations were considered: the elastic-semi-plastic and elastic-perfectly-plastic models for steel, and two tensile models for concrete with and without the post-cracking stresses. Meanwhile, Popovics’ model was used to describe the behavior of concrete under compression. Corrosion coefficients were developed as functions of corrosion degree and beam parameters through linear regression analysis to fit the theoretical moment capacities with test data. The performance of the coefficients derived from different combinations of constitutive laws was then compared and validated.

The results showed that the highest accuracy (R² = 0.90) was achieved when the tensile response of concrete was modeled without the residual stresses after cracking and the steel was analyzed as an elastic-perfectly-plastic material. The proposed procedure and regression model also showed reasonable agreement with experimental data, even performing better than the current models derived from accelerated tests and traditional procedures.

This study presents a simple but reliable approach for quantifying the capacity of RC beams under more realistic conditions than previously reported. This method is simple and requires only a few variables to be employed. Civil engineers can use it to obtain a quick and rough estimate of the structural condition of corroding RC beams.

Embedding carbon fiber reinforced plastics (CFRP) bars in the tension zone of reinforced concrete (RC) beams is a widely used reinforcement method, which has the advantages of strong anti-peel ability and high utilization of tensile materials. To further improve the flexural bearing capacity of RC beams, a new composite reinforcement method using the UHPC layer in the compressive zone of RC beams is proposed based on embedding CFRP bars in the tension zone of RC beams.

The finite element model of an RC experimental beam with CFRP bars embedded in the tension zone was carried out by ABAQUS. Besides, the reliability of the finite element model results was verified by comparing with the experimental results. On this basis, the flexural reinforcement effect of CFRP bars and UHPC layers on RC beams was analyzed.

Calculation results show the flexural bearing capacity of the beam strengthened by the new method is 15.9%, which is higher than that of the unreinforced beam, and 10.4% higher than that of the beam strengthened only with CFRP bars. The beam ductility ratio of the new method is 8.25%, which is slightly higher than that of the unreinforced beam and equal to that of the beam reinforced only with CFRP bars embedded in the tension zone. The effectiveness of the new method is further verified by using the analytical calculation method.

A new flexural reinforcement method for reinforced concrete beams is proposed, and the effectiveness of the method was verified by experiments and finite element model. The flexural bearing capacity and ductility of the new method were analyzed based on the load-deflection curve. Finally, the possibility of the new method was verified by analytical analysis.

Existing studies on crowdsourcing have focused on analyzing isolated contributions by individual participants and thus collaboration dynamics among them are under-investigated. The value of implementing crowdsourcing in problem solving lies in the aggregation of wisdom from a crowd. This study examines how marginality affects collaboration in crowdsourcing.

With population level data collected from a global crowdsourcing community (openideo.com), this study applied social network analysis and in particular bipartite exponential random graph modeling (ERGM) to examine how individual level marginality variables (measured as the degree of being located at the margin) affect the team formation in collaboration crowdsourcing.

Significant effects of marginality are attributed to collaboration skills, number of projects won, community tenure and geolocation. Marginality effects remain significant after controlling for individual level and team level attributes. However, marginality alone cannot explain collaboration dynamics. Participants with leadership experience or more winning ideas are also more likely to be selected as team members.

The core contribution this research makes is the conceptualization and definition of marginality as a mechanism in influencing collaborative crowdsourcing. This study conceptualizes marginality as a multidimensional concept and empirically examines its effect on team collaboration, connecting the literature on crowdsourcing to online collaboration.

The aim of this paper is to present a Eulerian–Lagrangian model of aircraft ground deicing that avoids the scale’s dispersion problem caused by the great distance between the spray nozzle and the surface to be deiced. Verification is done using the case of a hot particle liquid spray impinging on a horizontal flat plate. The impinged particles flow outwards radially from the impingement zone and form a hot film wall. The computed wall heat distribution is verified. In the end, an inclination spray’s angle study is presented.

The problem is divided into two regions. First, a 3D region is created for the evolution of the Lagrangian particles spray. A second 2D region is provided for the formation of a liquid film. The two regions exchange mass, momentum and energy through an interface. Heat losses are modelled through particles and liquid-film cooling and evaporation, particles splash and heat transfer to a fixed temperature plate.

For a chamber pressure of 1 bar, the predicted spray penetration is within 10 per cent of the experimental results. For this study case, the heat transfer is maximized with an inclination angle of approximately 30° of the spray.

The model presented makes it possible to simulate the impingement and heat transfer of a large-scale liquid spray with a reasonable computational cost. To the best of the authors’ knowledge, this model is a first attempt of the computational fluid dynamics simulation of ground deicing.

This paper presents an overview and discusses the applications of fibre reinforced polymer (FRP) bars as reinforcement in civil engineering structures. Following a discussion of the science underpinning their use, selected case studies where FRP reinforcement has been used are presented. The use of FRP reinforcement is rapidly gaining pace and may replace the traditional steel due to its enhanced properties and cost‐effectiveness. In addition, FRP reinforcement offers an effective solution to the problem of steel durability in aggressive environments and where the magnetic or electrical properties of steel are undesirable.

Seismic assessment procedures of RC members quantify member strength, deformation capacity and failure mode using detailed information regarding member geometry and reinforcement amount and arrangement. However, the condition of the reinforcing materials is not explicitly accounted for in the calculation process. The paper aims to discuss this issue.

This problem is explored in the present paper through consistent evaluation of the evidence from a database of column tests which were subjected to cyclic lateral load reversals simulating earthquake effects after being subjected to accelerated corrosion. The column performance expressed in terms of the shear vs drift resistance envelope is introduced in the available methodologies of rapid assessment of reinforced concrete structures showcasing the limitations and uncertainties of the existing state of the art in the field of seismic assessment of existing structures.

Simple estimations as well as experimental observation show that the effect can be staggering, in terms of reduced deformation capacity, prevailing mode of failure and residual strength under seismic loading. It has been observed in the field that deterioration and ageing can reduce a well detailed structural component to behave as a poorly constructed one, by means of cover delamination, transverse and longitudinal bar area loss and steel embrittlement.

The amount of deterioration in the residual life of the component, in the face of a future seismic hazard, is fraught with uncertainty regarding the amount and intensity of material deprecation and the manner in which this may be considered in the logistics of the assessment process.