Advances in the Analysis of Properties Behaviour of Cement-Based Grouts with High Substitution of Cement with Blast Furnace Slags

This article presents a study of the main properties (consistency, workability, leaching, unsoundness, and mechanical properties) of cement grouts prepared with cement replacement by blast furnace slag (GGBS). Mixtures have been analyzed in the absence of additives and reached high replacement percentages. As shown in the different tests presented, the observed evolution of the resistance and workability of the mixtures makes them very interesting for its application. Different types of cement (CEM-I 42.5 and CEM-I 52.5 R) and different water/binder values (1 and 0.67) are used. The results present opportunities for the steel industry by the intensive valorization of slag waste. The reduction of the use of cement in construction is also one of the key aims of this line of research. Results show improvements in the mechanical response with good fresh state properties for substitution percentages up to 70%. It is verified with leaching analysis that these products have less impact on the environmen

ROCOV scheme for Fault Detection and Location in HVDC sytems

A reliable DC fault protection system is essential for the development of HVDC grids. Therefore, this paper deals with the voltage derivative ROCOV scheme to locate and detect DC faults. The algorithm is able to differentiate internal and external faults considerably fast. The proposed algorithm is analyzed in a HVDC grid with different fault case scenarios. Finally, the ROCOV protection thresholds are discussed.The authors thank the support from the Spanish Ministry of Economy, Industry and Competitiveness (project ENE2016-79145-R AEI/FEDER, UE) and GISEL research group IT1083-16), as well as from the University of the Basque Country UPV/EHU (research group funding PPG17/23)

SWIPT techniques for multiuser MIMO broadcast systems

In this paper, we present an approach to solve the nonconvex optimization problem that arises when designing the transmit covariance matrices in multiuser multiple-input multiple-output (MIMO) broadcast networks implementing simultaneous wireless information and power transfer (SWIPT). The MIMO SWIPT design is formulated as a nonconvex optimization problem in which system sum rate is optimized considering per-user harvesting constraints. Two different approaches are proposed. The first approach is based on a classical gradient-based method for constrained optimization. The second approach is based on difference of convex (DC) programming. The idea behind this approach is to obtain a convex function that approximates the nonconvex objective and, then, solve a series of convex subproblems that, eventually, will provide a (locally) optimum solution of the general nonconvex problem. The solution obtained from the proposed approach is compared to the classical block-diagonalization (BD) strategy, typically used to solve the nonconvex multiuser MIMO network by forcing no inter-user interference. Simulation results show that the proposed approach improves both the system sum rate and the power harvested by users simultaneously. In terms of computational time, the proposed DC programming outperforms the classical gradient methods.Peer ReviewedPostprint (author's final draft

Wildfires & Drought Analysis for the Capital Area Council of Governments

Capital Area Council of Governments 2002-2012 Student: Emmanuel Rubio Perez Professor: Dr. James PhelpsAn analysis of available national data on droughts and wildfires indicate that Texas has encompassed a fluctuating drought for over a decade. The central and western portions of the state have been affected particularly severely. In 2011 for example, the Capital Area Council of Governments (CAPCOG) endured drastic drought and wildfire conditions. Counties such as Bastrop, made major news headlines as the Bastrop County Complex Fire consumed more than 30,000 acres. Not all the local and rural governmental authorities may have the necessary data or technology to analyze the challenging threats posed by drought or to effectively plan for the wildfire threats that have slowly developed to become part of the CAPGOC community. Therefore, the purpose of research is to muster the data of the enduring wildfire and drought conditions over the decade spanning 2002 to 2012 across the CAPCOG. This project formulated visual data of the historical archived conditions for the fire services, emergency managers, and community leaders within the CAPCOG jurisdiction in order to help enhance their mitigation efforts in relation to future drought and wildfire events

A Review of Wildfires and Drought Conditions for the Capital Area Council of Governments: 2002 to 2012

An analysis of available national data on droughts and wildfires indicate that Texas has encompassed a fluctuating drought for over a decade. The central and western portions of the state have been affected particularly severely. In 2011 for example, the Capital Area Council of Governments (CAPCOG) endured drastic drought and wildfire conditions. Counties such as Bastrop, made major news headlines as the Bastrop County Complex Fire consumed more than 30,000 acres. While the use of technology to track and manage wildfire threat has increased in recent years, a project I just completed in BOR 6302, Introduction to GIS, found that many smaller county and city fire services are lacking the historical digital data that could be used to prepare for future wildfires, mitigate the damage caused, and expedite recovery operations. Therefore, the purpose of research is to muster the data of the enduring wildfire and drought conditions over the decade spanning 2002 to 2012 across the CAPCOG. The research of acquired data incorporated within the archives kept by various organizations to include the Texas A&M Forest Service, Water Data for Texas Organization, Southern Regional Climate Center, Water Development Board, and the United States Drought Monitor. This project produced a visual data set of the historical drought and wildfire conditions for the fire services, emergency managers, and community leaders within that jurisdiction in order to help enhance their planning efforts for future events

Mapping the status and functions of English for research publication purposes in the biomedical field: Text-linguistic, ethnomethodological and ethnographic perspectives

The main aim of this PhD was to contribute to the examination of the role and functions of English as an international scientific language in Spain, and as the world language of scientific communication. It draws on three interrelated methodological approaches: a textual analysis (both at a rhetorical level and at a phraseological level) of texts aiming at disseminating new knowledge; an ethnomethodological analysis of scientists’ perceptions and attitudes towards English and towards writing in English as an additional language; and an ethnographic analysis of spaces, materials, and texts deployed by a small community of scientists in order to access, share and disseminate scientific knowledge. It was initially hypothesised that the triangulation of the three datasets would contribute with a multi-perspective view of English for research communication purposes in the biomedical field. Results support previous EAP work in the field of biomedicine and in other disciplinary domains. The analysis of a specialized corpus compiled for the present study showed that research writing draws of standardized conventions for information organization. Broadly, all the texts analysed adhered to the prototypical macrostructural organization for empirical research articles described by Swales (1990, 2004), although minor variations were also observed with regards the original IMRD Swalesian structure. Turning to writing practices, the interview data provided further evidence, added to those of others, of the spread of English as an international research language and the ensuing the language challenges that writing in English as an additional language poses to researchers from non-Anglophone linguacultural backgrounds. Ethnographic observation of the workspaces confirmed that both professional and research-oriented genres are the main means researchers draw upon to access, exchange and disseminate scientific knowledge. I finally conclude with some critical reflections deriving from the triangulation of the three datasets (texts, perceptions of writing practices and contexts in which such practices are carried out) and assess the role and status of English and the multiple factors affecting research writing with a view to providing both pedagogical and lifelong learning orientations. <br /

Development in Sustainable Concrete with the Replacement of Fume Dust and Slag from the Steel Industry

Nowadays, the reuse of waste is a challenge that every country in the world is facing in order to preserve the planet and introduce a circular economy. The chemical composition of some steel waste suggests that there are potentially appropriate substances for reuse, since this type of slag undergoes a process similar to that of cement in its manufacture. The advantages for the environment are obvious, as it valorises waste that is deposited in landfills. This paper studies the field of stainless steel, because its composition is different from that of carbon steel, and the replacement of cement with material or waste produced in the manufacture of stainless steel in a concrete matrix. This paper presents the results of replacing 25% of cement with material or waste produced in the manufacture of stainless steel in a concrete matrix whose values in the substitutions carried out were around 21% and 25% in terms of increased resistance capacity. These results have been obtained by carrying out tests, in terms of both strength and environmental capacity, allowing us to determine viable applications for the use of steel waste to improve the performance of cement or at least match it