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See detailApplication of Eurocode 3 to steel connections with four bolts per horizontal row
Demonceau, Jean-François ULg; Weynand, Klaus; Jaspart, Jean-Pierre ULg et al

in Batista, E.; Vellasco, P.; de Lima, L. (Eds.) Proceedings of the SDSS'Rio 2010 conference (2010, September)

Eurocode 3 Part 1-8 provides detailed application rules for the design of bolted end-plate connections. Although these rules apply to connections with any number of bolt rows, they are limited to ... [more ▼]

Eurocode 3 Part 1-8 provides detailed application rules for the design of bolted end-plate connections. Although these rules apply to connections with any number of bolt rows, they are limited to configurations with two bolts in each row. However, it is sometimes more economical to place four bolts in one row. This configuration is commonly met in different countries in Europe and, in particular, in Germany. The theoretical model on which the Eurocode 3 application rules are founded is general and can be potentially applied to connections with four bolts per row. However, specific design rules need to be developed. In the present paper, easy-to-apply analytical design rules aimed at predicting the mechanical properties of connections with four bolts per row and in full agreement with the Eurocode 3 approach are detailed. Validations through comparisons to experimental test results recently performed in the framework of a German national project are also presented. [less ▲]

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See detailApplication of experimental design for the HPLC-UV-MS separation of aporphine alkaloids from leaves of Spirospermum Penduliflorum thouars
Rafamantanana, Mamy H.; Debrus, Benjamin ULg; Raoelison, Guy E. et al

Poster (2010, September)

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See detailApplication of forensic science technique to the management of an endangered horse population
Bömcke, Elisabeth ULg; Gengler, Nicolas ULg

in Journal of Animal Science (2008), 86(E-suppl.2), 433

Implementing conservation strategies needs the knowledge of relationships inside the concerned population. The aim of the study was to find tools to help breeders to manage their horse population. The ... [more ▼]

Implementing conservation strategies needs the knowledge of relationships inside the concerned population. The aim of the study was to find tools to help breeders to manage their horse population. The Skyros pony is an indigenous Greek breed. The breed risk status is defined as critical-maintained according to the criteria from the Food and Agriculture Organization. Partial pedigree information is available, but its quality is poor as the average number of generation-equivalents is under 0.8 for the first known generation and under 1.4 for the second to the fifth. Further, 99 living individuals were genotyped at 16 microsatellite loci in order to check the registered parentage. For ungenotyped animals, conditional expectation of gene contents was calculated given molecular and pedigree data. As said in other studies, the animal genetics literature often seems unaware of relevant developments in human genetics (and conversely). In this study, an approach called Familial Searching was tested. This is used in forensic science, in addition to matching DNA evidence directly to criminal profiles, to search for people (present in a database) who are related to an individual that left DNA evidence at a scene of crime. This method is based on the calculation of likelihood ratios (LR) between genotype of an individual and genotypes of each other individuals of the database. The pedigree was used as ‘local’ prior information, i.e. relating to specific pairs of individuals. General knowledge about the studied population (generation interval, sexual maturity, …) was considered as ‘global’ prior information. Including prior information reduced the number of comparisons from over 50%. First results showed that the parents were always classified into the 5 highest LR. These results simplified parentage verifications, it allowed the detection of 90% of false parentage (LR=0). New links were created in the pedigree through detection of unregistered parents, what involved a reduction of the percentage of animals with one or both unknown parents and consequently an increase of the number of generation-equivalents. The pedigree of the breed was thus improved. [less ▲]

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See detailApplication of four lead systems to quantitative electrocardiography in calves
Amory, Hélène ULg; Rollin, Frédéric ULg; Lekeux, Pierre ULg

in Archives Internationales de Physiologie et de Biochimie (1990)

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See detailAn application of fuzzy random variables to control charts
Faraz, Alireza ULg; Shapirob, Arnold

in Fuzzy Sets & Systems (2010), 161(20), 26842694

The two most significant sources of uncertainty are randomness and incomplete information. In real systems, we wish to monitor processes in the presence of these two kinds of uncertainty. This paper aims ... [more ▼]

The two most significant sources of uncertainty are randomness and incomplete information. In real systems, we wish to monitor processes in the presence of these two kinds of uncertainty. This paper aims to construct a fuzzy statistical control chart that can explain existing fuzziness in data while considering the essential variability between observations. The proposed control chart is an extension of Shewhart ¯X − S2 control charts in fuzzy space. The proposed control chart avoids defuzzification methods such as fuzzy mean, fuzzy mode, fuzzy midrange, and fuzzy median. It is well known that using different representative values may cause different conclusions to be drawn about the process and vague observations to be reduced to exact numbers, thereby reducing the informational content of the original fuzzy sets. The out-of-control states are determined based on a fuzzy in-control region and a simple and precise graded exclusion measure that determines the degree to which fuzzy subgroups are excluded from the fuzzy in-control region. The proposed chart is illustrated with a numerical example. [less ▲]

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See detailApplication of genetic algorithms to lubrication pump stacking design
Kelner, Vincent ULg; Léonard, Olivier ULg

in Journal of Computational & Applied Mathematics (2004), 168(1-févr Sp. Iss. SI), 255-265

Sizing a pump stacking used in an aircraft lubrication system is a challenging task. The combination of several pumps, in parallel and in a single casing, must deliver specified oil flow rates, on a ... [more ▼]

Sizing a pump stacking used in an aircraft lubrication system is a challenging task. The combination of several pumps, in parallel and in a single casing, must deliver specified oil flow rates, on a variable number of circuits, and under given flight conditions. Furthermore, the optimal assembly has to minimize overall dimensions, weight and cost. This optimization problem involves a large space search, continuous and discrete variables and multi-objectives. Genetic Algorithms (GA)-stochastic search methods that mimic the metaphor of natural biological evolution-seem well suited to solve that kind of problems. A new GA is proposed. The efficiency of this GA is first demonstrated in solving various mathematical test-cases and then applied to the industrial problem. (C) 2003 Elsevier B.V. All rights reserved. [less ▲]

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See detailAPPLICATION OF GEOMATICS FOR THE ASSESSMENT OF PASTORAL RESOURCES IN MOROCCO
Mahyou, Hamid ULg

Doctoral thesis (2012)

Rangeland or natural arid pastures of Morocco are defined as ecosystems where there is a natural or semi-natural vegetation composed of steppes, shrubs and grassland used mainly for livestock production ... [more ▼]

Rangeland or natural arid pastures of Morocco are defined as ecosystems where there is a natural or semi-natural vegetation composed of steppes, shrubs and grassland used mainly for livestock production as climate and soil are unsuitable to agriculture. The arid rangelands of Morocco occupy an area of over 33 million hectares between the isohyets of 100 and 400 mm. These areas represent livelihoods for thousands of people and protect the country from desertification. The main objective of this study is to provide scientific community and decision-makers methodological tools for assessing arid rangelands, based on geomatics and biophysics data. This study is divided in four parts: 1. The first part presents an overview of the threat of the desertification, emphasizes on the causes and consequences of rangeland degradation in Morocco, from literature sources, statistics, climate data and maps. Morocco rangelands are located in ten different pastoral zones that differ from each other by their floristic composition, soil and climatic conditions. According to Globcover map these rangelands are mainly composed by bare soil, herbaceous vegetation, shrubs and deciduous savanna mosaic / shrub or forest. The largest pastoral zones are: the Saharan zone, Pre-Saharan, the Oriental plateaus and the Valley of Moulouya. These zones are the most degraded with respectively 97, 89 and 69% of their total area. Available information on several pilot areas shows that the Moroccan rangelands are degraded due to many factors, which include overgrazing, cultivation, population increase and climate variation. 2. The second part of the study demonstrates the usefulness of remote sensing for assessing drought in arid rangelands of Morocco. Bi-weekly TERRA Moderate Resolution Imaging Spectroradiometer (MODIS 250 meters) data were used for this purpose. A Preliminary mapping by using Landsat TM5 of major land cover types was carried out to extract the pasture area. A comparison of annual and seasonal Normalised Difference Vegetation Indices (NDVI), Vegetation Condition Index (VCI) and rainfall during the time period of 2000–2008 were carried out. Results show significant correlations of either NDVI (r= 0.72**) or VCI (r=0.42*) with past season (3 months) rainfall. NDVI variation is a good indicator of vegetation changes and consequently can give a reliable indication on drought conditions in the study area. NDVI values lower than 0.2 are indicative of drought occurrence. NDVI values between 0.20 and 0.28 indicate average weather conditions and values higher than 0.28 correspond to humid conditions. 3. The third part presents an original knowledge-based approach for mapping the degradation of rangelands in North Africa. The study area is located in the high plateaus of eastern Morocco which include 3.5 million hectares of arid rangeland steppes. The approach consists in using datasets derived from Landsat TM satellite imagery, lithology, phytogeographic data and field indicators. The field indicators are: the steppes composition, perennial vegetation cover, annual perennial production, grazing level and the prevalence of rangeland cultivation. Results show that the knowledge-based approach is a valid method for evaluating rangeland degradation. The proposed knowledge-based approach discriminated between rangeland categories that would not have been discernible using only remote sensing. Overall classification accuracy of rangeland degradation obtained using this approach was 93%. This approach revealed that 11, 36 and 30% of the study area have shown very severe, severe and moderate degradation level, respectively. 4. The fourth part concerns the assessment of Alfa grass (Stipa tenacissima) tussocks at various degradation levels of Alfa grass steppes in the high plateaus of eastern Morocco, based on field hyperspectral data (350 – 2500 nm) and digital images during fall and spring seasons. Digital images of Alfa grass tussocks were taken using a digital camera to classify of the tussocks according to their proportion in green leaves (green, mixed and dry tussock). Assess software (Image Analysis Software for Plant Disease Quantification, APS 2002) was used to obtain the proportion of greenness in each tussock. Hyperspectral data of three states of tussocks (Green, Mixed and Dry tussock leaves) were collected within three degradation levels of Alfa grass steppes (Slight, Moderate and Severe degradation) with the ASD FieldSpec® 3 spectroradiometer. Paired t-test, Normalized difference spectral reflectance (NDSR) and Stepwise Discriminate Analysis were used to discriminate between various tussock status and different Alfa grass steppes. The results indicate that Alfa grass had shown an intraspecific variability in reflectance spectra. The proportion of green leaves in Alfa grass tussock strongly influences the spectral response. The discrimination of different Alfa grass tussock status was better during fall than spring. The spectral behavior of Alfa grass tussock is problematic for the mapping and the assessment of Alfa grass steppes by conventional remote sensing techniques. [less ▲]

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See detailApplication of groundwater models in karstic aquifers
Dassargues, Alain ULg

in Leibundgut, Christian; Gunn, John; Dassargues, Alain (Eds.) Karst Hydrology (Proc. of Rabat Workshop W2) (1998)

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See detailApplication of heparin as a dual agent with antimalarial and liposome targeting activities toward Plasmodium-infected red blood cells
Marques, J.; Moles, E.; Urbán, P. et al

in Nanomedicine (2014), 10(1719–1728),

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See detailApplication of High-Performance Liquid Chromatography to the Study of Thiamine Metabolism and in Particular Thiamine Triphosphatase
Bettendorff, Lucien ULg

in Journal of Chromatography. A (1991), 566(2), 397-408

Thiamine triphosphate can be found in most tissues at very low levels, but its role is unknown. Organs and muscles that generate electrical impulses are particularly rich in this compound. This paper ... [more ▼]

Thiamine triphosphate can be found in most tissues at very low levels, but its role is unknown. Organs and muscles that generate electrical impulses are particularly rich in this compound. This paper describes a thiamine triphosphatase from the electrical organ of Electrophorus electricus. The activity of this enzyme, as measured by a high-performance liquid chromatographic method, is closely anion-regulated. Furthermore, thiamine triphosphate increases chloride uptake in membrane vesicles prepared from rat brain. Our results suggest that this compound could play an important role in the regulation of chloride permeability. [less ▲]

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See detailApplication of Higher-Order Harmonic Balance to Non-Linear Aeroelastic Systems
Dimitriadis, Grigorios ULg; Vio, Gareth Arthur; Cooper, Jonathan Edward

in Proceedings of the 47th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference (2006, May)

The influence of non-linearities on modern aircrafts is becoming of increasing impor- tance. The ability to accurately characterise LCOs and to predict at which speed they occur is very important. Higher ... [more ▼]

The influence of non-linearities on modern aircrafts is becoming of increasing impor- tance. The ability to accurately characterise LCOs and to predict at which speed they occur is very important. Higher Order Harmonic Balance (HOHB) methods have attracted some interest from the aeroelastic community over the last two decades. Such methods carry the promise of high quality stability prediction and Limit Cycle Oscillation (LCO) amplitude and frequency prediction for non-linear aeroelastic systems. In this paper, a Higher Order Harmonic Balance scheme is devised to extend the effectiveness of the method to systems undergoing secondary Hopf bifurcations. It is shown that the proposed harmonic shifting technique can allow the HOHB method to accurately estimate both branches of limit cycles occurring after the second bifurcation. [less ▲]

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See detailApplication of hyperspectral Raman imaging to the analysis of a self-emulsifying drug delivery system (SEDDS).
Sacre, Pierre-Yves ULg; De Bleye, Charlotte ULg; Netchacovitch, Lauranne ULg et al

Poster (2014, June)

Self-emulsifying drug delivery systems (SEDDS) are mixtures of drug and excipients that undergo emulsification when exposed to water. This pharmaceutical form is used to enhance the oral absorption of ... [more ▼]

Self-emulsifying drug delivery systems (SEDDS) are mixtures of drug and excipients that undergo emulsification when exposed to water. This pharmaceutical form is used to enhance the oral absorption of poorly water-soluble drugs. The API is finely dispersed in the excipients and forms a solid solution increasing its dissolution rate. Hyperspectral Raman imaging is a powerful tool that combines both spectral and spatial information. It returns qualitative and quantitative information useful during the development or the characterization of pharmaceutical preparations. The studied formulation consisted of a BCS 2 API (high permeability, low solubility) dispersed in excipients mainly composed of Lauroyl macrogol-32 glycerides (>50%). Two different preparations were analyzed: 100% of API dissolved and 70% of API dissolved with 30% of API powder added to the formulation. The two formulations have therefore exactly the same qualitative and quantitative composition but different spatial distribution and dispersion of the API mimicking a problem during the process. First a confocal Raman microscopic analysis was performed to evaluate the solid state of the API in the formulations. Then, an evaluation of the particle size was performed. These results are important since they can affect the bioavailability of the API and therefore its activity. Beside the microscopic scale analysis, a macroscopic imaging quantitative PLS model has been developed. The method has been validated within +/- 10% acceptance limits following the total error approach. This validated quantitative model enables reliable quantitative analysis at the pixel level of Raman images providing meaningful chemical images. [less ▲]

Detailed reference viewed: 50 (8 ULg)