376 research outputs found
SARCOS Round Robin Test 5 : evaluating test methods for self-healing concrete with macrocapsules
The Missing Science: Ethics in Practice
The Greeks argued that philosophy was the most important science even though it was a science that studied no things. Their science, philosophy, focused on the meaning of life and death, life after death, existence, knowledge, knowing the good and bad, as well as the application of right and wrong. We argue that what is right and what is wrong should underlie the development of the current book Sports and Exercise Science. The stated purposes of the book, “to present the up to date knowledge about etiology, pathogenesis, diagnosis, management and prevention of chronic injuries or sports related long term changes in locomotor system. Moreover, topics about influence of sports activities on growth and development in pediatric population and presentation of acute injuries that often develop to chronic…as well,” are topics that should be addressed through science in sports and exercise science—philosophy and ethics. Ethics should govern all science, including the growth and development of sports and exercise science. Injury often occurs because of poor coaching, poor training, or overtraining. The problem exists because of unethical practice of either coaches, parents, leaders, trainers, or a combination of all of them. This chapter focuses on ethical education for professionals, educators, practitioners, and coaches
Fatty acid composition and sensory acceptability of dry cured ham influenced by linseed oil, fish oil or microalgae included in the pig feed
Economic capital for Dutch retail banking books : a study on the effects of embedded options in dutch retail banking books on interest rate risk and economic capital
In this thesis we study the effects of embedded options in the retail banking book on interest rate risk and economic capital. In chapter 1 we give an introduction to the field. Further we define some core concepts and describe the research goal and research questions in that\ud
chapter. The goal of this research is to study the effects of embedded options in the retail banking book on interest rate risk and economic capital. To reach this goal, we start with a study of banking risks in general in chapter 2. At the end of that study we provide a general risk typology, thereby answering research question one
First large scale application with self-healing concrete in Belgium : analysis of the laboratory control tests
Due to the negative impact of construction processes on the environment and a decrease in investments, there is a need for concrete structures to operate longer while maintaining their high performance. Self-healing concrete has the ability to heal itself when it is cracked, thereby protecting the interior matrix as well as the reinforcement steel, resulting in an increased service life. Most research has focused on mortar specimens at lab-scale. Yet, to demonstrate the feasibility of applying self-healing concrete in practice, demonstrators of large-scale applications are necessary. A roof slab of an inspection pit was cast with bacterial self-healing concrete and is now in normal operation. As a bacterial additive to the concrete, a mixture called MUC+, made out of a Mixed Ureolytic Culture together with anaerobic granular bacteria, was added to the concrete during mixing. This article reports on the tests carried out on laboratory control specimens made from the same concrete batch, as well as the findings of an inspection of the roof slab under operating conditions. Lab tests showed that cracks at the bottom of specimens and subjected to wet/dry cycles had the best visual crack closure. Additionally, the sealing efficiency of cracked specimens submersed for 27 weeks in water, measured by means of a water permeability setup, was at least equal to 90%, with an efficiency of at least 98.5% for the largest part of the specimens. An inspection of the roof slab showed no signs of cracking, yet favorable conditions for healing were observed. So, despite the high healing potential that was recorded during lab experiments, an assessment under real-life conditions was not yet possible
Contemporary analysis and numerical simulation of revisited long-term creep tests on reinforced concrete beams from the Sixties
The stresses and deformations in concrete change over time as a result
of the creep- and shrinkage deformations of concrete. Different material models
are available in literature in order to predict this time-dependent behaviour. These
material models mostly have been calibrated on large datasets of creep specimens.
In order to verify the accuracy of the contemporary material models with
respect to the prediction of the creep behaviour of reinforced concrete beams, a
cross-sectional calculation tool which employs the age-adjusted effective modulus
has been developed and used to analyse an original set of 4 year-long creep
data on reinforced beams from the 1960’s. Six commonly used material models
for the prediction of creep and shrinkage are considered in the current investigation:
CEB-FIP Model Code 1990–1999, fib Model Code 2010, the model of
EN1992-1-1, model B3, the Gardner Lockmann 2000 model, and ACI 209. The
data on reinforced beams relates to an experimental investigation in collaboration
with six major research institutes in Belgium. From 1967 until 1972 thirty-two
reinforced beams with different reinforcement ratios were subjected, up until 4.5
years, to different stress levels in a four point bending configuration with a span
of 2.8 m. In this paper a comparison between the measurements and the calculated
deflections and strains is reported. Further, the deflections were also predicted
using the contemporary creep models in combination with the nonlinear
creep correction factor provided in EN1992-1-1, since the maximum concrete
stresses in the beams were outside the service stress range of each of the models.
Correcting for the nonlinearity of the creep coefficient significantly improves the
calculated deflections. The most accurate predictions of the deflections at early
age were obtained by the model of fib Model Code 2010. The Gardner Lockmann
2000 model exhibits the highest accuracy with respect to deflections at the end of
loading and with respect to the creep rate
Recherche de partenaires de la protéine Dim1p par suppression phénotypique de mutants dim1 conditionnels
Influence of long-term creep on prestressed concrete beams in relation to deformations and structural resistance : experiments and modeling
Realistic structural models incorporating the time-dependent effects of concrete are essential in order to make accurate predictions of the time-dependent deflections at any time of the service life. Experimental databases are used to calibrate and validate existing models for creep and shrinkage available in international standards. However, extensive research campaigns on large-scale prestressed beams are scarce. In 1967-1985, a research program comprising a unique set of long-term experimental data on concrete beams was conducted in joint collaboration with four Belgian research institutes to determine the influence of creep and shrinkage on the long-term behavior of reinforced and prestressed concrete members. The main aim of the final part of the research campaign was the determination of the long-term behavior of prestressed and partially prestressed beams subjected to permanent loads, considering the influence of the magnitude of the loads, the degree of prestressing, the shape of the cross-section, the type of prestressing and the stress conditions. This paper reports on the obtained unique set of long-term tests. Additionally, also information related to the creep and shrinkage data of prisms and the results of the static tests in a four-point bending configuration until failure at the age of 28 days and 5 years are presented in this paper. The measurements of the prestressed members are compared with a simplified calculation method based on the direct stiffness method, which accounts for aging, creep, and shrinkage. The proposed simplified calculation model allows fast and accurate predictions of strains, stresses, and deflections as a function of time. The results show that the direct stiffness method in combination with the current models of EN1992-1-1 and fib Model Code 2010 can predict the long-term behavior of concrete beams in good agreement with the available experimental data. The research allows to develop more accurate calculation guidelines with respect to the evolution of deflections, concrete deformations and stresses of prestressed beams as function of the prestress-degree, shape of the cross-section, and the type of prestressing
CCE 92-05 intercomparison of ac-dc voltage transfer standards at high frequencies (1-50 MHz)
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