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See detailIdentification of the linear parts of nonlinear systems for fuzzy modeling
Rezaei Sadrabadi, Mahmood ULg

in Applied Soft Computing (2011), 11

In direct approach to fuzzy modeling, structure identification is one of the most critical tasks. In modeling the nonlinear system, this fact is more crucial. In this paper, a new hybrid method is ... [more ▼]

In direct approach to fuzzy modeling, structure identification is one of the most critical tasks. In modeling the nonlinear system, this fact is more crucial. In this paper, a new hybrid method is proposed to cluster the data located in the linear parts on the nonlinear systems. The proposed method can partition the input–output data in two groups: data located in the linear parts and data in the extrema. It is shown that the first group of data is suitable to be clustered by Fuzzy C-Regression Model (FCRM) clustering algorithm and the second group by Fuzzy C-Means (FCM). Then, based on the above findings, a new hybrid clustering algorithm is proposed. Finally, the proposed approach is tested and validated by several numerical examples of nonlinear functions. [less ▲]

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See detailIdentification of the major pregnancy-specific antigens of cattle and sheep as inactive members of the aspartic proteinase family
Xie, Sancai; Low, Boon G.; Nagel, Robert J. et al

in Proceedings of the National Academy of Sciences of the United States of America (1991), 88(22), 10247-10251

Pregnancy in cattle and sheep can be diagnosed by the presence of a conceptus-derived antigen in maternal serum that is secreted by trophoblast and placental tissue primarily as an acidic component of Mr ... [more ▼]

Pregnancy in cattle and sheep can be diagnosed by the presence of a conceptus-derived antigen in maternal serum that is secreted by trophoblast and placental tissue primarily as an acidic component of Mr 67,000. Molecular cloning of its cDNA reveals that the antigen belongs to the aspartic proteinase family and has greater than 50% amino acid sequence identity to pepsin, cathepsin D, and cathepsin E. The inferred sequences of the ovine and bovine polypeptides show approximately 73% identity to each other. Critical amino acid substitutions at the active site regions suggest that both proteins are enzymatically inactive. The antigen is a product of trophoblast binucleate cells that invade maternal endometrium at implantation sites. [less ▲]

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See detailIdentification of the Mechanical and Piezoelectric Parameters of a Massively Piezoelectric Structure
De Boe, P.; Pascual, R.; Golinval, Jean-Claude ULg

Conference given outside the academic context (1998)

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See detailIdentification of the nonlinear function in a vibrating nonlinear beam
Dimitriadis, Grigorios ULg; Cooper, Jonathan E

in Lees, A. W.; Prells, U.; Norton, J. (Eds.) Proceedings of the Third International Conference on Identification in Engineering Systems (2002, April)

The Constant Level Identification (CLI) method for nonlinear dynamical systems has been shown to identify accurately a wide variety of systems with discrete degrees of freedom. In this paper, the method ... [more ▼]

The Constant Level Identification (CLI) method for nonlinear dynamical systems has been shown to identify accurately a wide variety of systems with discrete degrees of freedom. In this paper, the method is applied to a continuous nonlinear system, namely a simulated model of a vibrating beam attached to a nonlinear spring. A Rayleigh-Ritz series representation of the beam is assumed in order to extract the desired number of modal responses. Then, a combination of modal and physical coordinates are used in the identification process. It is shown that the CLI method can accurately capture the shape of the nonlinearity in the system. [less ▲]

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See detailIdentification of the Origin of Catecholaminergic Inputs to Hvc in Canaries by Retrograde Tract Tracing Combined with Tyrosine Hydroxylase Immunocytochemistry
Appeltants, D.; Absil, Philippe ULg; Balthazart, Jacques ULg et al

in Journal of Chemical Neuroanatomy (2000), 18(3), 117-33

The telencephalic nucleus HVc (sometimes referred to as the high vocal center) plays a key role in the production and perception of birdsong. Although many afferent and efferent connections to this ... [more ▼]

The telencephalic nucleus HVc (sometimes referred to as the high vocal center) plays a key role in the production and perception of birdsong. Although many afferent and efferent connections to this nucleus have been described, it has been clear for many years, based on chemical neuroanatomical criteria, that there are projections to this nucleus that remain undescribed. A variety of methods including high performance liquid chromatography, immunohistochemistry and receptor autoradiography have identified high levels of catecholamine transmitters, the presence of enzymes involved in the synthesis of catecholamines such as tyrosine hydroxylase and a variety of catecholamine receptor sub-types in the HVc of several songbird species. However, no definitive projections to HVc have been described from cells groups known to synthesize catecholamines. These projections were analyzed in the present study by retrograde tract tracing combined with immunocytochemistry for tyrosine hydroxylase. The origin of the catecholaminergic inputs to HVc were determined based exclusively on birds in which injections of the retrograde tracer (latex fluospheres) were confined within the cytoarchitectonic boundaries of the nucleus. Retrogradely transported latex fluospheres were found mainly in cells of two dopaminergic nuclei, the mesencephalic central gray (A11) and, to a lesser extend, the area ventralis of Tsai (A10; homologous to the ventral tegmental area of mammals). A few retrogradely-labelled cells were also found in the noradrenergic nucleus subceruleus (A6). Most of these retrogradely-labelled cells were also tyrosine hydroxylase-positive. Other catecholaminergic nuclei were devoid of retrograde label. These data converge with others studies to indicate that HVc receives discrete dopaminergic and noradrenergic inputs. These inputs may influence the steroid regulation of HVc, attentional processes related to song and modulate sensory inputs to the song system. [less ▲]

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See detailIdentification of the parameters of a damage constitutive law for steel at elevated temperature
Castagne, S.; Habraken, Anne ULg

in Banabic, D. (Ed.) Proceedings of the 8th ESAFORM Conference on Material Forming (2005)

This paper presents the methodology and the results of the calibration of an interface damage law using experimental damage analyses and associated finite element simulations. The experimental damage ... [more ▼]

This paper presents the methodology and the results of the calibration of an interface damage law using experimental damage analyses and associated finite element simulations. The experimental damage analyses consist in acoustic tests realised on steel samples in order to determine the apparition of the first crack during compression. Finite elements simulations of these experiments allow the determination of the damage parameters using a reverse method. [less ▲]

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See detailIdentification of the perosamine synthetase gene of Brucella melitensis 16M and involvement of lipopolysaccharide O side chain in Brucella survival in mice and in macrophages.
Godfroid, F.; Taminiau, Bernard ULg; DANESE, Isabelle ULg et al

in Infection and Immunity (1998), 66(11), 5485-93

Brucella organisms are facultative intracellular bacteria that may infect many species of animals as well as humans. The smooth lipopolysaccharide (S-LPS) has been reported to be an important virulence ... [more ▼]

Brucella organisms are facultative intracellular bacteria that may infect many species of animals as well as humans. The smooth lipopolysaccharide (S-LPS) has been reported to be an important virulence factor of these organisms, but the genetic basis of expression of the S-LPS O antigen has not yet been described. Likewise, the role of the O side chain of S-LPS in the survival of Brucella has not been clearly defined. A mini-Tn5 transposon mutant library of Brucella melitensis 16M was screened by enzyme-linked immunosorbent assay (ELISA) with monoclonal antibodies (MAbs) directed against the O side chain of Brucella. One mutant, designated B3B2, failed to express any O side chain as confirmed by ELISA, Western blot analysis, and colony coloration with crystal violet. Nucleotide sequence analysis demonstrated that the transposon disrupted an open reading frame with significant homology to the putative perosamine synthetase genes of Vibrio cholerae O1 and Escherichia coli O157:H7. The low G+C content of this DNA region suggests that this gene may have originated from a species other than a Brucella sp. The survival of B. melitensis mutant strain B3B2 in the mouse model and in bovine macrophages was examined. The results suggested that S-LPS or, more precisely, its O side chain is essential for survival in mice but not in macrophages. [less ▲]

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See detailIdentification of the post-maximum lines in the spectrum of Nova (RS) Ophiuchi.
Joy, A. H.; Swings, Polydore ULg

in Astrophysical Journal (1945), 102

Interest in the spectra of recurring novae has been aroused by the recent (fourth) outburst of Nova (T) Pyxidis. A review of the hitherto unpublished measures of the Mount Wilson spectrograms of Nova (RS ... [more ▼]

Interest in the spectra of recurring novae has been aroused by the recent (fourth) outburst of Nova (T) Pyxidis. A review of the hitherto unpublished measures of the Mount Wilson spectrograms of Nova (RS) Ophiuchi obtained between September 2 and November 10, 1933, shows many plausible identifications of lines which were impossible earlier. The atoms now identified, in addition to H, are: He I, He II, C III, [N II], N m, [O I], O III, [O III], [Ne III], [Ne IV], Na I, Si I, Si II, Si III, Si IV, [S II], [S III], [A V], [A X], [A XI], [K IV], [K V], [Ca V], [Ca VI], [Ca VII], [Ca XIII], [Sc VII], [V VIII], Fe II, [Fe II], [Fe IV], [Fe V], [Fe VI], [Fe VII], [Fe X], [Fe XI], [Fe XIV], [Ni XII], [Kr III]. Of these, [A XI] λ 6919, [Ca VII] λ 3688 (and possibly [V VIII] λ 3686), [Sc VII] λ 4823, and [Kr III] λ 6827 are identified for the first time. Considerations of the physical conditions in the solar corona as compared with those in the recurrent novae indicate marked differences, the coronal strata not permitting radiation of forbidden lines in the lower stages of ionization such as are found in the novae. [less ▲]

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See detailIdentification of the post-maximun lines in the spectrum of nova (RS) Ophiuchi.
Joy, A.-H.; Swings, Polydore ULg

in Contributions from the Mount Wilson Observatory (1945), 714

Interest in the spectra of recurring novae has been aroused by the recent (fourth) outburst of Nova (T) Pyxidis. A review of the hitherto unpublished measures of the Mount Wilson spectrograms of Nova (RS ... [more ▼]

Interest in the spectra of recurring novae has been aroused by the recent (fourth) outburst of Nova (T) Pyxidis. A review of the hitherto unpublished measures of the Mount Wilson spectrograms of Nova (RS) Ophiuchi obtained between September 2 and November 10, 1933, shows many plausible identifications of lines which were impossible earlier. The atoms now identified, in addition to H, are: He I, He II, C III, [N II], N III, [O I], O III, [O III], [Ne III], [Ne IV], Na I, Si I, Si II, Si III, Si IV, [S II], [S III], [A V], [A X], [A XI], [K IV], [K V], [Ca V], [Ca VI], [Ca VII], [Ca XIII], [Sc VII], [V VIII], Fe II, [Fe II], [Fe IV], [Fe V], [Fe VI], [Fe VII], [Fe X], [Fe XI], [Fe XIV], [Ni XII], [Zr III]. Of these, [A XI] λ 6919, [Ca VII] λ 3688 (and possibly [V VIII] λ 3686), [Sc VII] λ 4823, and [Kr III] λ 6827 are identified for the first time. Considerations of the physical conditions in the solar corona as compared with those in the recurrent novae indicate marked differences, the coronal strata not permitting radiation of forbidden lines in the lower stages of ionization such as are found in the novae. [less ▲]

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See detailIdentification of the signalling pathways required for interleukin-1 beta stimulation of osteoprotegerin synthesis in osteoblastic cells
Lambert, Cecile; Ribbens, Clio ULg; Bours, Vincent ULg et al

in Journal of Bone and Mineral Research (2003, September), 18(Suppl. 2), 142

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See detailIdentification of the Slow-Flow Dynamics of Transonic Aeroelastic Response from Time-Series Data
Lee, Y. S.; Vakakis, Alexander F.; McFarland, D. M. et al

in 45th Technical Meeting of the Society of Engineering Science, Urbana Champaign, 2008 (2008)

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See detailIdentification of Three-Element Windkessel Model: Comparison of Time and Frequency Domain Techniques
Pochet, T.; Gérard, Paul ULg; Marnette, J. M. et al

in Archives Internationales de Physiologie, de Biochimie et de Biophysique (1992), 100(3, May-Jun), 295-301

The problem of the parameter identification of the three-element windkessel model is studied. Minimization by least-square technique--LSQ--in time domain and frequential techniques--FFT--are compared ... [more ▼]

The problem of the parameter identification of the three-element windkessel model is studied. Minimization by least-square technique--LSQ--in time domain and frequential techniques--FFT--are compared. Continuous pressure and flow curves were recorded in the proximal aorta of an open chest dog. Comparison shows very high correlations between the parameter estimations obtained by LSQ and FFT methods. However, systematic differences appear between the calculated values, but do not seem to endanger physiological interpretation of the results. [less ▲]

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See detailIdentification of type II and type III pyoverdine receptors from Pseudomonas aeruginosa.
de Chial, Magaly; Ghysels, Bart ULg; Beatson, Scott A. et al

in Microbiology (Reading, England) (2003), 149(Pt 4), 821-31

Pseudomonas aeruginosa produces, under conditions of iron limitation, a high-affinity siderophore, pyoverdine (PVD), which is recognized at the level of the outer membrane by a specific TonB-dependent ... [more ▼]

Pseudomonas aeruginosa produces, under conditions of iron limitation, a high-affinity siderophore, pyoverdine (PVD), which is recognized at the level of the outer membrane by a specific TonB-dependent receptor, FpvA. So far, for P. aeruginosa, three different PVDs, differing in their peptide chain, have been described (types I-III), but only the FpvA receptor for type I is known. Two PVD-producing P. aeruginosa strains, one type II and one type III, were mutagenized by a mini-TnphoA3 transposon. In each case, one mutant unable to grow in the presence of the strong iron chelator ethylenediaminedihydroxyphenylacetic acid (EDDHA) and the cognate PVD was selected. The first mutant, which had an insertion in the pvdE gene, upstream of fpvA, was unable to take up type II PVD and showed resistance to pyocin S3, which is known to use type II FpvA as receptor. The second mutant was unable to take up type III PVD and had the transposon insertion in fpvA. Cosmid libraries of the respective type II and type III PVD wild-type strains were constructed and screened for clones restoring the capacity to grow in the presence of PVD. From the respective complementing genomic fragments, type II and type III fpvA sequences were determined. When in trans, type II and type III fpvA restored PVD production, uptake, growth in the presence of EDDHA and, in the case of type II fpvA, pyocin S3 sensitivity. Complementation of fpvA mutants obtained by allelic exchange was achieved by the presence of cognate fpvA in trans. All three receptors posses an N-terminal extension of about 70 amino acids, similar to FecA of Escherichia coli, but only FpvAI has a TAT export sequence at its N-terminal end. [less ▲]

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See detailIdentification of undeclared sources of animal origin in canine dry foods used in dietary elimination trials
Ricci, Rebecca; Granato, A; Vascellari, M et al

in Journal of Animal Physiology & Animal Nutrition (2013), 97

Failure to respond to commercial limited antigen diets can occur in dogs kept on a dietary trial for the diagnosis of adverse food reaction (AFR). The aim of this study was to assess twelve canine dry ... [more ▼]

Failure to respond to commercial limited antigen diets can occur in dogs kept on a dietary trial for the diagnosis of adverse food reaction (AFR). The aim of this study was to assess twelve canine dry limited antigen diets (eleven novel protein diets and one hydrolysed diet) for potential contamination by ingredients of animal origin not mentioned on the label. The validity of the two methods adopted for the detection of such food antigens was also evaluated. Each dietary product was analysed by microscopy analysis using the official method described in Commission Regulation EC 152/2009 with the aim of identifying bone fragments of different zoological classes (mammalian, avian and fish) and by polymerase chain reaction (PCR) for the identification of DNA of animal origin. Discrepancies between the results obtained by PCR and/or microscopy analysis and the ingredients listed on pet food packages were found. Only in two pet foods did the results of both analyses match the ingredients listed on the label. In the remaining ten samples, microscopy detected bone fragments from one or two unpredicted zoological classes, revealing avian fragments in six of ten samples followed by those of fish in five of ten and mammalian fragments in four of ten. In two samples, microscopy analysis identified a contamination that would have otherwise passed unobserved if only PCR had been used. However, PCR confirmed the presence of all the zoological classes detected by microscopy and also identified the DNA of an additional unexpected zoological class in two samples. Dogs might fail to respond to commercial limited antigen diets because such diets are contaminated with potential allergens. Both PCR and microscopy analysis are required to guarantee the absence of undeclared animal sources in pet foods. Before ruling out AFR, a novel protein home-made diet should be considered if the dog is unresponsive to a commercial regimen. [less ▲]

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See detailIdentification of viable myocardium early after acute myocardial infarction using closed-loop arbutamine echocardiography: comparison with positron emission tomography
PIERARD, Luc ULg; MELON, Pierre ULg; LANCELLOTTI, Patrizio ULg et al

in Acta Cardiologica (2001), 56(6), 387-394

Objective -This study sought to evaluate the safety and efficacy of arbutamine echocardiography in identifying contractile reserve and predicting functional improvement early after acute myocardial ... [more ▼]

Objective -This study sought to evaluate the safety and efficacy of arbutamine echocardiography in identifying contractile reserve and predicting functional improvement early after acute myocardial infarction (AMI). Methods and results - Seventeen patients with first AMI underwent arbutamine echocardiography 48 to 96 hours after AMI. Arbutamine was infused by a closed-loop delivery device. The heart rate slope was 4 beats/min and the heart rate target was 20 beats/min above baseline heart rate. A follow-up echocardiogram was obtained one month later. N- 13 ammonia and F- 18 FDG positron emission tomographic (PET) imaging were performed 6 2 days after AMI, before coronary angiography. Mean duration of arbutamine infusion was 6 2 min. There was no complication and there were no major side effects. Myocardial viability was identified with PET in 15 of the 17 patients. Contractile reserve was observed in 10 patients during arbutamine infusion. Functional recovery was identified in 12 patients. Sensitivity, specificity and accuracy of PET and arbutamine echocardiography for predicting functional recovery were 100%, 40%, 76% and 67%, 80%, 84%, respectively. Conclusions - Low-dose arbutamine stress testing is safe early after AMI. Contractile reserve can be rapidly identified by echo cardiography and is specific, but moderately sensitive for predicting reversible dysfunction. [less ▲]

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See detailIdentification of wire rope isolators using the restoring force surface method
Kerschen, Gaëtan ULg; Lenaerts, Vincent; Golinval, Jean-Claude ULg

in International Conference on Structural Systems Identification, Kassel, 2001 (2001)

The restoring force surface method offers an efficient and reliable identification of non-linear single-degree-of-freedom systems. The method may be extended to multidegree-of-freedom systems but by ... [more ▼]

The restoring force surface method offers an efficient and reliable identification of non-linear single-degree-of-freedom systems. The method may be extended to multidegree-of-freedom systems but by loosing the key advantage of the method which lies in the two-dimensional representation for single-degree-of-freedom systems. An experimental application of the restoring force surface method is considered in the present paper. The structure investigated consists of wire rope isolators mounted between a load mass and a base mass. These helical isolators were found to be characterised by a non-linear behaviour. The results obtained are discussed in details and the advantages and drawbacks of the method are underlined. [less ▲]

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See detailIdentification of yield locus parameters of metals using inverse modeling and full field DIC
Lecompte, D.; Cooreman, S.; Sol, H. et al

in Proceedings of the 7th national congress on theoretical and applied mechanics (2006)

The basic principle of the inverse modeling procedure as it is used for parameter identification is the generation of a complex and heterogeneous deformation field that contains as much information as ... [more ▼]

The basic principle of the inverse modeling procedure as it is used for parameter identification is the generation of a complex and heterogeneous deformation field that contains as much information as possible about the parameters to be identified. One way of obtaining such a non-homogeneous deformation is by making the geometry of the specimen less regular. Another possibility is to make the loading conditions more complex. In this paper both options are actually combined by using the concept of a biaxial tensile test on a perforated cruciform specimen. In the present paper, the work hardening of the material is assumed to be isotropic and it is described by a Swift law. The yield locus is modeled by the anisotropic Hill48 criterion. The optimization technique used is a constrained gradient based Newton-type routine, which means that in every iteration step, a sensitivity calculation has to be performed in order to indicate the direction in which the parameters are to be optimized. The functional to be minimized is a least-squares expression of the discrepancy between the measured and the simulated strain fields at a certain load. The numerical routines as well as the identification results of the different parameters, based on simulated strain fields, are discussed. [less ▲]

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