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Article
Publication date: 25 April 2022

Ayoub Abou Houraira, Abdellah Ouali, Ouafa Elhammoumi and Ahmed Fekri

Morocco is facing climate change, as shown by national studies conducted to date. The purpose of our research work is, on one hand, to develop an experimental protocol;…

Abstract

Purpose

Morocco is facing climate change, as shown by national studies conducted to date. The purpose of our research work is, on one hand, to develop an experimental protocol; simulating the Moroccan climate, through exposing concretes to accelerated aging in different cycles of temperature variation (+5 to +40 C°) and humidity (60–98% RH) and on another hand, to determine the effect of exposure to temperature and humidity variation cycles on the durability indicators (of concrete [with and without thermal cure]).

Design/methodology/approach

For this purpose, three classes of concrete were studied (C35, C40 and C55). Each class of concrete was considered first with no addition of silica fume (SF) and then with a 10% addition of SF. The concrete samples underwent three types of conditioning before performing the tests. The control concretes (Ct) were demoulated after 24 h and stored under stable temperature and humidity conditions (20 ± 2 °C and 80% ± 5 RH). Treated concretes (CV) demouled after 24 h and exposed to 300 cycles of 12 h of temperature and moisture variation in a climate chamber. And finally, concretes that have undergone a heat cure (CTV) for 5 h at 90 °C, were then removed from the mold and exposed to temperature and moisture variations cycles identical to treated concrete (CV).

Findings

The results obtained show that aging accelerated by temperature change, and humidity improves durability indicators compared to Ct. Concretes that have undergone a thermal cure, followed by accelerated aging, show an improvement in durability indicators between 50 and 200 cycles, but the performance of concrete decreases after 200 exposure cycles. The addition of SF plays a beneficial role in the durability of concrete in the three exposure environments.

Originality/value

The originality of the work is, to develop an experimental protocol, simulating the Moroccan climate, through exposing concretes to accelerated aging in different cycles of temperature variation (+5 to +40 C°) and humidity (60–98% RH) and on another hand, to determine the effect of exposure to temperature and humidity variation cycles on the durability indicators of conventional concrete (with and without thermal cure).

Details

International Journal of Building Pathology and Adaptation, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 1 February 1974

Roberta A. Scull

This annotated listing of 131 United States Government bibliographies with 1973 imprints partially represents the broad scope of Federal interest. THE MONTHLY CATALOG OF…

Abstract

This annotated listing of 131 United States Government bibliographies with 1973 imprints partially represents the broad scope of Federal interest. THE MONTHLY CATALOG OF U.S. GOVERNMENT PUBLICATIONS was the primary index searched in locating these documents, though other conventional and unconventional methods were used. Since the search cut‐off date was the February 1974 MONTHLY CATALOG, a number of 1973 bibliographies may not be listed here. However, it is the compiler's objective to include all 1973 bibliographies in a forthcoming Pierian Press publication, BIBLIOGRAPHY OF UNITED STATES GOVERNMENT BIBLIOGRAPHIES 1968–1973.

Details

Reference Services Review, vol. 2 no. 2
Type: Research Article
ISSN: 0090-7324

Article
Publication date: 19 August 2021

Oliver Bahr

This paper aims to answer two questions. First, are there any differences in the fire performance of columns made of normal and of high-strength concrete? Second, under…

Abstract

Purpose

This paper aims to answer two questions. First, are there any differences in the fire performance of columns made of normal and of high-strength concrete? Second, under which circumstances does the fire design govern the cross-sectional dimensions of concrete columns? Is it feasible to replace columns out of normal strength concrete by more slender high-strength concrete columns?

Design/methodology/approach

The author conducted numerical studies using the finite element code “Infocad” of the German company “Infograph”. The studies included the effect of different parameters on the fire performance of columns out of normal and high-strength concrete, i.e. the load ratio and eccentricity, boundary conditions and times of fire exposure.

Findings

Results from the numerical investigations showed that high-strength concrete columns suffer much more from heating than normal strength concrete columns. This is the outcome of the unfavourable mechanical properties of high-strength concrete at elevated temperatures. Although the relative fire performance of columns out of high-strength concrete is worse than that of columns out of normal strength concrete, initial load reserves are beneficial to achieve even high fire ratings.

Originality/value

Many researchers addressed in experimental and numerical studies the fire performance of columns out of normal and high-strength concrete. A special emphasis was often laid on the spalling of fire-exposed high-strength concrete. However, there are no systematic investigations when the fire design governs the cross-sectional dimensions of high-strength concrete columns. Based on a previous comparison of the relative fire performance of columns out of normal and high-strength concrete, this paper, hence, addresses the question whether there is a reasonable lower limit for the use of these columns. This is an important aspect for designers since there is a tendency to replace columns out of normal strength concrete by columns out of high-strength concrete. Higher concrete strengths allow for smaller cross sections of the columns, and designers may, hence, increase the usable space of buildings.

Details

Journal of Structural Fire Engineering, vol. 12 no. 4
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 1 March 1982

Jim Segesta

This article is about reference books that can answer questions about the typical weather for a city in the United States or the actual weather on a given day in the past.

Abstract

This article is about reference books that can answer questions about the typical weather for a city in the United States or the actual weather on a given day in the past.

Details

Reference Services Review, vol. 10 no. 3
Type: Research Article
ISSN: 0090-7324

Article
Publication date: 1 April 1976

Roberta A. Scull

This compilation of over 500 United States Government bibliographies is the second annual supplement to BIBLIOGRAPHY OF UNITED STATES GOVERNMENT BIBLIOGRAPHIES 1968–1973…

Abstract

This compilation of over 500 United States Government bibliographies is the second annual supplement to BIBLIOGRAPHY OF UNITED STATES GOVERNMENT BIBLIOGRAPHIES 1968–1973 (Pierian Press). Due to the Government Printing Office backlog during 1974, many 1973 and 1974 titles are included in this 1975 Supplement, which should have appeared earlier.

Details

Reference Services Review, vol. 4 no. 4
Type: Research Article
ISSN: 0090-7324

Book part
Publication date: 8 June 2021

Adwaita Maiti, Sebak Kumar Jana and Asim K. Karmakar

The present century is an age of knowledge-based economy. Higher education is in the process of transformation and thereby challenging the traditional system of education…

Abstract

The present century is an age of knowledge-based economy. Higher education is in the process of transformation and thereby challenging the traditional system of education in India. The present paper reviews the current conditions of ICT use by the students in higher education in India. The major objectives of the study are (1) assessment of the use of computer and Internet by the students of higher education in India and (2) to find the determinants of use of ICT by the students in India. The study uses the NSSO 71st Round Unit Level Data on Social Consumption: Education Survey (71st Round, 2014). The present paper is based on 6,035 students from all the regions in India out of which 3,127 students were from the rural area and 2,908 from the urban area. The findings from logit analysis suggest that the determinants of ICT use by the students in higher education in India are regional disparities, gender, education levels of households, type of courses pursued by the students, type of institutions, access to computer and Internet facility, consumption levels of households, and students' residence type.

Details

Comparative Advantage in the Knowledge Economy
Type: Book
ISBN: 978-1-80071-040-5

Keywords

Book part
Publication date: 19 July 2022

Ayesha Banu

Introduction: The Internet has tremendously transformed the computer and networking world. Information reaches our fingertips and adds data to our repository within a…

Abstract

Introduction: The Internet has tremendously transformed the computer and networking world. Information reaches our fingertips and adds data to our repository within a second. Big data was initially defined as three Vs, where data come with greater variety, increasing volumes and extra velocity. Big data is a collection of structured, unstructured and semi-structured data gathered from different sources and applications. It has become the most powerful buzzword in almost all the business sectors. The real success of any industry can be counted based on how the big data is analysed, potential knowledge is discovered and productive business decisions are made. New technologies such as artificial intelligence and machine learning have added more efficiency to storing and analysing data. This big data analytics (BDA) becomes more valuable to those companies, focusing on getting insight into customer behaviour, trends and patterns. This popularity of big data has inspired insurance companies to utilise big data at their core systems and advance the financial operations, improve customer service, construct a personalised environment and take all possible measures to increase revenue and profits.

Purpose: This study aims to recognise what big data stands for in the insurance sector and how the application of BDA has opened the door for new and innovative changes in the insurance industry.

Methodology: This study describes the field of BDA in the insurance sector, discusses the benefits, outlines tools, architectural framework, the method, describes applications in general and specific and briefly discusses the opportunities and challenges.

Findings: The study concludes that BDA in insurance is evolving into a promising field for providing insight from very large data sets and improving outcomes while reducing costs. Its potential is great; however, there remain challenges to overcome.

Details

Big Data: A Game Changer for Insurance Industry
Type: Book
ISBN: 978-1-80262-606-3

Keywords

Book part
Publication date: 19 November 2014

Benjamin J. Gillen, Matthew Shum and Hyungsik Roger Moon

Structural models of demand founded on the classic work of Berry, Levinsohn, and Pakes (1995) link variation in aggregate market shares for a product to the influence of…

Abstract

Structural models of demand founded on the classic work of Berry, Levinsohn, and Pakes (1995) link variation in aggregate market shares for a product to the influence of product attributes on heterogeneous consumer tastes. We consider implementing these models in settings with complicated products where consumer preferences for product attributes are sparse, that is, where a small proportion of a high-dimensional product characteristics influence consumer tastes. We propose a multistep estimator to efficiently perform uniform inference. Our estimator employs a penalized pre-estimation model specification stage to consistently estimate nonlinear features of the BLP model. We then perform selection via a Triple-LASSO for explanatory controls, treatment selection controls, and instrument selection. After selecting variables, we use an unpenalized GMM estimator for inference. Monte Carlo simulations verify the performance of these estimators.

Book part
Publication date: 1 June 2022

Luca Tiozzo Pezzoli and Elisa Tosetti

Seismometers continuously record a wide range of ground movements not caused by earthquake activity, but rather generated by human activities such as traffic, industrial…

Abstract

Seismometers continuously record a wide range of ground movements not caused by earthquake activity, but rather generated by human activities such as traffic, industrial machinery functioning and industrial processes. In this Chapter we exploit seismic data to predict variations in Gross Domestic Product (GDP) for a set of States in the USA over the period from 2016 to 2021. We measure the noise generated at specific frequencies that are linked to human activity and use it as an indicator of economic activity. We show a remarkable reduction in seismic noise due to a slowdown in traffic and economic activities during the Corona economic crisis. Our results point at seismic data as a valuable source of information that can be used for monitoring regional and national economies.

Details

The Economics of COVID-19
Type: Book
ISBN: 978-1-80071-694-0

Keywords

Book part
Publication date: 10 April 2019

Christopher S. Henry and Tamás Ilyés

For central banks who study the use of cash, acceptance of card payments is an important factor. Surveys to measure levels of card acceptance and the costs of payments can…

Abstract

For central banks who study the use of cash, acceptance of card payments is an important factor. Surveys to measure levels of card acceptance and the costs of payments can be complicated and expensive. In this paper, we exploit a novel data set from Hungary to see the effect of stratified random sampling on estimates of payment card acceptance and usage. Using the Online Cashier Registry, a database linking the universe of merchant cash registers in Hungary, we create merchant and transaction level data sets. We compare county (geographic), industry and store size stratifications to simulate the usual stratification criteria for merchant surveys and see the effect on estimates of card acceptance for different sample sizes. Further, we estimate logistic regression models of card acceptance/usage to see how stratification biases estimates of key determinants of card acceptance/usage.

Details

The Econometrics of Complex Survey Data
Type: Book
ISBN: 978-1-78756-726-9

Keywords

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