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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]).

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).

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.

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).

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.

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.

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?

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.

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.

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.

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.

Extensive literature studies the causes of crime and crime reporting behaviour. In contrast, there is hardly any scholarship on delays in reporting a crime and what drives them. Understanding delays in reporting crimes is important for various reasons, for example, because they could decrease the likelihood of an arrest or lead to an issue with the statute of limitations. This paper is the first to analyse the delay in reporting crimes and environmental drivers of these delays.

The authors construct a novel data set combining all crimes reported in New York City from 2006 to 2020 (N = 2,442,288) with station-level data on weather variables (temperature, rainfall, relative humidity, visibility and wind speed) and four types of air pollutants (carbon monoxide, ozone, sulphur dioxide, nitrogen dioxide). Matching these three data sets using the geolocation occurs at an hourly frequency. Importantly, the crime data provided by the NYPD allows us to control for several other factors that could potentially affect crime reporting behaviour.

The authors show that 30 percent of reported crimes in New York City were reported with a delay. The average reporting delay was 10.79 days. Carbon monoxide influences for delays in reporting violent crimes and rainfall affects delays in reporting property crimes. Relative humidity, as a driver of wet bulb temperature, affects delays in reporting violent crimes as well.

The authors present novel facts about delays in reporting crimes and how these are related to weather and air pollution. The authors’ findings have implications for government regulation of air pollution as well as for real-time crime forecasting. They should also aid victim support groups in providing services.

This paper is the first to analyse the impact of environmental factors on the delay in reporting crimes.

The financial turbulence resulting from the global financial crisis sparked the interest in improving understanding of financial risks. The transmission of financial institution failures can be determined from the prevailing network structures between banks. The purpose of this study is to identify relationship between payment system network characteristics and financial system condition.

The characteristics of the interbank network structure in the payment system are identified using a graph theory and the relationship between the network characteristics of interbank transactions in the payment system and financial system stability is examined using a vector auto regression model.

This study shows that the connectedness of large-value payment transaction is more segmented compared to that of retail value payments. A significant relationship is observed between the characteristics of the network and the large-value payment transactions.

This study found the connectedness of large-value transactions is more segmented when compared to retail-value transactions. It also shows a causal effect of the network characteristic on the financial system stability.

Unlike existing studies, this study considers both the connectedness in large-value transactions and retail-value transactions.

The purpose of this paper is to compute an aggregate misalignment index using a multiple indicator approach to identify under- or over-valuation of house prices in Malta based on fundamentals.

A total of six indicators are used that capture households, investors and system-wide factors: the house price-to-Retail Price Index ratio, the price-to-hypothetical borrowing volume ratio, price-to-construction costs ratio, price-to-rent ratio, dwelling investment-to-GDP ratio and the loan bearing capacity. The weights are derived using principal component analysis. The analysis is performed using both the house price indices of the National Statistics Office (NSO) and the Central Bank of Malta (CBM), which are based on contract and advertised prices, respectively.

House prices in Malta were overvalued by around 20 to 25 per cent in the pre-crisis boom. This disequilibrium started to be corrected following the decline in house prices, with the CBM and NSO house price cycles reaching a trough in 2013 and 2014, respectively. At the trough, house prices were undervalued by around 10 to 15 per cent. Since then, house prices started to recover although the recovery in advertised prices was more pronounced compared to that based on contract prices. In mid-2017, advertised house prices were slightly overvalued, while contract prices still have to reach their equilibrium level. The dynamics from the misalignment index, including its peaks and troughs, are remarkably similar to the range derived from statistical filters.

Estimates of house price misalignment have both economic and financial stability implications.

This paper allows for a decomposition of the house price cycle, tailored for the particular characteristics of the Maltese housing market. It also takes into account the relationship between house prices and private sector rents, which in recent years have been buoyed, among other factors, by the high inflow of foreign workers and changing patterns in the tourism industry.

The purpose of this paper is to explore whether the out-of-sample model bias plays an important role in predicting volatility.

Under the heterogeneous autoregressive realized volatility (HAR-RV) framework, we analyze the predictive power of out-of-sample model bias for the realized volatility (RV) of the Dow Jones Industrial Average (DJI) and the S&P 500 (SPX) indices from in-sample and out-of-sample perspectives respectively.

The in-sample results reveal that the prediction model including the model bias can obtain bigger R², and the out-of-sample empirical results based on several evaluation methods suggest that the prediction model incorporating model bias can improve forecast accuracy for the RV of the DJI and the SPX indices. That is, model bias can enhance the predictability of original HAR family models.

The author introduce out-of-sample model bias into HAR family models to enhance model capability in predicting realized volatility.

The materials included in this column were selected on the basis of an item by item review of all government publications received at a major depository library. Emphasis is placed on tools of a reference format, although much else that the Federal government publishes is otherwise of high referral value. Publications not in a reference format, in the strictest sense, are included when their potential value dictates; brief entries for “how to” items and informative pamphlets are also given if deemed potentially useful, particularly for school and public libraries and wherever the identification of vertical file materials is the responsibility of the public service librarian.