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See detailDistributed load interruption and shedding against voltage delayed recovery or instability
Otomega, Bogdan; Van Cutsem, Thierry ULg

in Proc. IEEE PES 2013 PowerTech Conference (2013, June)

This paper deals with a two-part system integrity protection scheme to be installed in distribution networks, to counteract fault-induced delayed voltage recovery or even short-term voltage instability ... [more ▼]

This paper deals with a two-part system integrity protection scheme to be installed in distribution networks, to counteract fault-induced delayed voltage recovery or even short-term voltage instability due to induction motors. The first part consists of a fast triggered but temporary reduction of some loads to facilitate motor re-acceleration after fault clearing. The second part resorts to load shedding, as a back-up. The scheme relies on purely distributed controllers; each of them measures a bus voltage and interrupts/disconnects load at the same bus. Tests have been performed on a generic MV/LV system. They illustrate the benefit of load interruption and the selectivity of the proposed scheme. [less ▲]

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See detailDistributed Model-free Control of Photovoltaic Units for Mitigating Overvoltages in Low-Voltage Networks
Aristidou, Petros ULg; Olivier, Frédéric ULg; Hervas, Maria Emilia et al

in Proc. of CIRED 2014 workshop (2014, June)

In this paper, a distributed model-free control scheme to mitigate overvoltage problems caused by high photovoltaic generation in low-voltage feeders is proposed. The distributed controllers are ... [more ▼]

In this paper, a distributed model-free control scheme to mitigate overvoltage problems caused by high photovoltaic generation in low-voltage feeders is proposed. The distributed controllers are implemented on the photovoltaic inverters and modulate the active and reactive power injected into the network. In particular, they direct photovoltaic units first to consume reactive power and, if necessary, curtail active power generation to reduce high voltages in the feeder. [less ▲]

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See detailDistributed MPC of wide-area electromechanical oscillations of large-scale power systems
Wang, Da ULg; Glavic, Mevludin; Wehenkel, Louis ULg

in Proceedings of ISAP 2011 (2011, September)

We investigate distributed Model Predictive Control (MPC) to damp wide-area electromechanical oscillations. Our distributed MPC schemes are derived from and compared with a fully centralized MPC scheme ... [more ▼]

We investigate distributed Model Predictive Control (MPC) to damp wide-area electromechanical oscillations. Our distributed MPC schemes are derived from and compared with a fully centralized MPC scheme proposed in a previous publication. Based on simulations carried out using a 16-generator, 70-bus, two-area test power system, we show that simple coordination schemes based on additional local measurements’ feedback yield already a significant improvement with respect to a scheme with only implicit coordination, improve significantly with respect to purely local controls, and in this respect reach about 75% of the improvements obtained by an ideal centralized MPC scheme. [less ▲]

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See detailA Distributed Signal Processing Architecture
Filip, A. E.; Arthur, James S.; Drinan, John D. et al

Report (1983)

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See detailA distributed stream temperature model using high resolution temperature observations
Westhoff, Martijn ULg; Savenije, H. H. G.; Luxemburg, W. M. J. et al

in Hydrology and Earth System Sciences (2007), 11(4), 1469-1480

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See detailDistributed undervoltage load shedding
Otomega, Bogdan; Glavic, Mevludin; Van Cutsem, Thierry ULg

in IEEE Transactions on Power Systems (2007), 22(4), 2283-2284

A new design of load shedding against long-term voltage instability is proposed. It uses a set of distributed controllers, each monitoring a transmission voltage, controlling a group of loads, acting in ... [more ▼]

A new design of load shedding against long-term voltage instability is proposed. It uses a set of distributed controllers, each monitoring a transmission voltage, controlling a group of loads, acting in closed-loop, and adjusting its action to the voltage evolution. The whole system operates without information exchange between controllers. [less ▲]

Detailed reference viewed: 91 (2 ULg)
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See detailDe distributie van goederen en de licentieovereenkomst
Vanbrabant, Bernard ULg; Van Couter, Yves

in Bestendig Handboek Distributierecht (2007)

Detailed reference viewed: 51 (4 ULg)
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See detailDistributing the Optical Near-Field for Efficient Field-Enhancements in Nanostructures
Valev, V; De Clercq, B; Biris, C et al

in Advanced Materials (2012), 24

Circularly polarized light imparts a sense of rotation on the electron density in ring-shaped gold nanostructures. As a consequence, the near-field enhancement becomes homogeneous on the surface of the ... [more ▼]

Circularly polarized light imparts a sense of rotation on the electron density in ring-shaped gold nanostructures. As a consequence, the near-field enhancement becomes homogeneous on the surface of the nanostructures, thereby increasing the opportunity for interaction with molecules. This type of nanostructured samples can find a broad range of applications in chemical processes where the interaction between molecules and local field enhancements play an important role. [less ▲]

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See detailDistribution amplitude for the photon-pion transition
Courtoy, Aurore ULg; Noguera, S.

in PoS - Proceedings of Science (2008), LC2008

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See detailDistribution and accumulation pattern of perfluorooctane sulfonic acid (PFOs) in marine mammals from the North Sea
Van de Vijver, Kristin; Das, Krishna ULg; Van Dongen, W. et al

Poster (2002, November)

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See detailDistribution and air-water exchange of carbon dioxide in the Scheldt plume off the Belgian coast
Borges, Alberto ULg; Frankignoulle, Michel

in Biogeochemistry (2002), 59((1-2)), 41-67

In the present paper we report partial pressure of CO2 (pCO2) data obtained off the Belgian coast during 24 cruises. The temporal and spatial resolution of this data set allows us to discuss ... [more ▼]

In the present paper we report partial pressure of CO2 (pCO2) data obtained off the Belgian coast during 24 cruises. The temporal and spatial resolution of this data set allows us to discuss satisfactorily seasonal and inter-annual variability of pCO2 in the study area. The dynamics of pCO2 are described using two approaches: fixed reference stations and area survey cruises. The air-water fluxes of CO2 in the Scheldt estuarine plume and in the outerplume region are estimated quantitatively, showing that these areas correspond respectively to a net annual source and sink of atmospheric CO2. The annually integrated air-water fluxes for the Scheldt estuarine plume range between +1.1 and +1.9 mol m−2 year−1 as a function of the formulation of the exchange coefficient of CO2. The annual net emission of CO2 from the estuarine plume to the atmosphere is estimated to be between +2.3 to +4.0 Gmol year−1 which represents 17 to 29% of the estimate reported in the literature for the Scheldt inner estuary. [less ▲]

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See detailDistribution and characteristics of aquatic habitats of newts and yellow-bellied toads in the district of Ioannina (Epirus, Greece)
Denoël, Mathieu ULg

in Herpetozoa (2004), 17(1/2), 49-64

The study describes the aquatic habitats and distribution of Triturus alpestris veluchiensis Wolterstorff 1935, T. carnifex macedonicus (Karaman, 1922), T. vulgaris graecus (Wolterstorff, 1905) and ... [more ▼]

The study describes the aquatic habitats and distribution of Triturus alpestris veluchiensis Wolterstorff 1935, T. carnifex macedonicus (Karaman, 1922), T. vulgaris graecus (Wolterstorff, 1905) and Bombina variegata scabra (Küster, 1843) in the district (“nomos”) of Ioannina, Northern Greece. Bombina variegata was found to be the most common species, followed by T. alpestris and T. carnifex while T. vulgaris seemed to be rare. The four taxa differed in habitat use and geographic distribution. Records of T. alpestris were limited to the highest sites in the north and east of the district. This species inhabited alpine lakes, but also smaller habitats such as drinking troughs and ponds. Four populations contained paedomorphic individuals. Triturus vulgaris appeared to be restricted to low altitude sites in the centre of the district where it lived in reservoirs, watering basins and drinking troughs. Triturus carnifex and B. variegata had a wider distribution and occupied a broader spectrum of habitats. Bombina variegata was the only species studied which lived in running waters (small brooks). Neither newts nor yellow-bellied toads were found in large rivers and lakes. In the district of Ioannina both habitat variety and distribution range of newts and Yellow-bellied Toads turned out to be greater than previously known. Alpine lakes containing very large populations of paedomorphic individuals should be protected given the rarity of the phenomenon. [less ▲]

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See detailDistribution and composition of organic carbon in the Tana River Basin, (Kenya)
Tamooh, F.; van den Meersche, K.; Borges, Alberto ULg et al

Poster (2011)

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See detailDistribution and composition of organic carbon in the Tana River Basin, (Kenya)
Tamooh, F.; van den Meersche, K.; Borges, Alberto ULg et al

Conference (2011, February 13)

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See detailDistribution and epidermal growth factor receptor expression of primordial follicles in human ovarian tissue before and after cryopreservation.
Qu, Jian Ping; Godin, Pierre-Arnaud; NISOLLE, Michelle ULg et al

in Human Reproduction (2000), 15(2), 303-10

The freezing of ovarian tissue and the growth of immature oocytes from primordial follicles is an interesting concept in ovarian tissue transplantation and in-vitro fertilization. In this study, the ... [more ▼]

The freezing of ovarian tissue and the growth of immature oocytes from primordial follicles is an interesting concept in ovarian tissue transplantation and in-vitro fertilization. In this study, the morphology and distribution of primordial follicles were studied in ovarian tissue from 24 women before and after cryopreservation. Cryopreservation did not significantly change either the morphology or number per unit volume of morphologically normal follicles in frozen ovarian tissue. Primordial follicles were predominant, accounting for 78.6% and 82.6% of total follicles in fresh and frozen ovarian tissues respectively. The distribution of follicles was extremely uneven in ovarian tissue. A large variation in follicle numbers was observed in ovarian tissue samples from patient to patient, and even in the same patient, indicating that the number of follicles counted in one sample of ovarian tissue may not represent the number of follicles in other tissue samples. Ovarian tissue could be frozen in the form of strips instead of fragments for fast processing and better viability of ovarian tissue in cryopreservation. The number of follicles in ovarian tissue declined with the increasing age of the patients. An immunohistochemical study showed that immunoreactivity for the epidermal growth factor (EGF) receptor was detected in primordial follicles of adult ovarian tissue. EGF receptor staining was most intense in the oocytes of primordial follicles. Weak staining for EGF receptor was observed in some surrounding pregranulosa cells. Immunohistochemical staining for EGF receptor was also present in the stromal cells of ovarian tissue, but to a much lesser degree. There was no significant difference in the immunohistochemical staining for EGF receptor in ovarian tissue before and after cryopreservation. [less ▲]

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See detailDistribution and evolution of ferripyoverdine receptors in Pseudomonas aeruginosa.
Bodilis, Josselin; Ghysels, Bart ULg; Osayande, Julie et al

in Environmental microbiology (2009), 11(8), 2123-35

Pseudomonas aeruginosa is a ubiquitous gram-negative bacterium, which is also able to cause severe opportunistic infections in humans. The colonization of the host is importantly affected by the ... [more ▼]

Pseudomonas aeruginosa is a ubiquitous gram-negative bacterium, which is also able to cause severe opportunistic infections in humans. The colonization of the host is importantly affected by the production of the high-affinity iron (III) scavenging peptidic siderophore pyoverdine. The species P. aeruginosa can be divided into three subgroups ('siderovars'), each characterized by the production of a specific pyoverdine and receptor (FpvA). We used a multiplex PCR to determine the FpvA siderovar on 345 P. aeruginosa strains from environmental or clinical origin. We found about the same proportion of each type in clinical strains, while FpvA type I was slightly over-represented (49%) in environmental strains. Our multiplex PCR also detected the presence or absence of an additional receptor for type I pyoverdine (FpvB). The fpvB gene was in fact present in the vast majority of P. aeruginosa strains (93%), regardless of their siderovar or their origin. Finally, molecular analyses of fpvA and fpvB genes highlighted a complex evolutionary history, probably linked to the central role of iron acquisition in the ecology and virulence of P. aeruginosa. [less ▲]

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See detailDistribution and identification of molecular interactions between tomato roots and bacterial biofilms
Debois, Delphine ULg; Jourdan, Emmanuel; Smargiasso, Nicolas ULg et al

Poster (2013, June 12)

Some non-pathogenic microorganisms evolving in the root micro-environment can trigger a positive effect on plant, increasing host defense against disease or/and directly inhibiting growth of pathogen in ... [more ▼]

Some non-pathogenic microorganisms evolving in the root micro-environment can trigger a positive effect on plant, increasing host defense against disease or/and directly inhibiting growth of pathogen in soil (1). To initiate both phenomena leading to biocontrol activity, microorganisms use plant exudates to grow on roots and to produce in-situ active compounds. In Bacilli, cyclic lipopeptides of the surfactin, iturin and fengycin families represent important antibiotics involved in biocontrol (2). Recent studies in microbiology allowed a better understanding of plant microorganism interactions but few has been done at the molecular level. In this study, MALDI MS imaging has been used to study the nature of the secreted lipopeptide molecules, their relative quantity and their distribution in the root’s environment.Disinfected tomato seeds were first germinated at 28°C in sterile conditions for germination. Seedlings were then placed in Petri dish on ITO glass slide recovered with a thin layer of plant nutritive solution containing 1,75% of agar and treated with freshly-grown cells of Bacillus amyloliquefaciens S499. Petri dishes were incubated at 28°C with a 16h photoperiod. Different growth / incubation durations were studied: 10/3; 13/7; 21/14 and 39/32. For MALDI imaging experiments, the ITO slide was removed from the agar and dried in a dessiccator under vacuum. (HCCA, 5mg/mL in ACN/0.2% TFA 70:30) was used as matrix. UltraFlex II TOF/TOF and Solarix FT-ICR mass spectrometers were used to record molecular cartographies and perform MS/MS experiments for structural analysis purposes. The average mass spectra recorded around the tomato root (2-3 mm on both sides of the root) showed that lipopeptides were major compounds detected on the agar. The relative intensity of lipopeptides families varied with respect to the age of the root/biofilm system. In the 10/3 system, 3 homologues of surfactins were essentially detected (C13, C14 and C15), with very few iturins and fengycins. Their localizations were identical, whatever the considered homologue. Then the production of iturin and fengycin families increases in older systems (13/7 and 21/14) and a novel homologue of surfactin is detected (C12). Some variations in localizations within families may be observed (around the root or at the close vicinity of it in function of the considered homologue or alkali adduct). Then for the oldest system we studied, iturins and fengycins are not detected anymore and the localization of surfactins is less precise. In the 39/32 system, we also detected unknown compounds at 986.6, 1000.6, 1014.7 and 1028.7 m/z. The mass range of these compounds allied to the mass difference between two consecutive ion peaks let us think that these unknown compounds could be a new lipopeptide family. Tandem mass spectrometry experiments, performed on the dried culture medium, allowed to partially sequence these new lipopeptides. MS/MS results allied to exact mass measurements and isotopic pattern simulation give good confidence in the chemical structure we suggest. Nevertheless, to fully identify these new variants of surfactin, micro-extractions followed by (LC)-nano-ESI-MS/MS using a LESA module are in progress. MALDI Mass Spectrometry Imaging becomes a tool to decipher inter-species molecular communication. [less ▲]

Detailed reference viewed: 83 (17 ULg)