985 resultados para Dolet, Etienne, 1509-1546.
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This paper presents a control design for tracking of attitude and speed of an underactuated slender-hull unmanned underwater vehicle (UUV). The control design is based on Port-Hamiltonian theory. The target dynamics (desired dynamic response) is shaped with particular attention to the target mass matrix so that the influence of the unactuated dynamics on the controlled system is suppressed. This results in achievable dynamics independent of uncontrolled states. Throughout the design, insight of the physical phenomena involved is used to propose the desired target dynamics. The performance of the design is demonstrated through simulation with a high-fidelity model.
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Despite considerable state investment and initiatives, binge drinking is still a major behavioral problem for policy makers and communities in many parts of the world. Furthermore, the practice of bingeing on alcohol seems to be spreading to young people in countries traditionally considered to have moderate drinking behaviors. Using a sociocultural lens and a framework of sociocultural themes from previous literature to develop propositions from their empirical study, the authors examine binge-drinking attitudes and behaviors among young people from high and moderate binge-drinking countries. The authors then make proposals regarding how policy makers can use social marketing more effectively to contribute to behavior change. Qualitative interviews were conducted with 91 respondents from 22 countries who were studying in two high binge-drinking countries at the time. The results show support for three contrasting sociocultural propositions that identify influences on binge drinking across these countries.
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Influenza is associated with substantial disease burden [ 1]. Development of a climate-based early warning system for in fluenza epidemics has been recommended given the signi fi - cant association between climate variability and influenza activity [2]. Brisbane is a subtropical city in Australia and offers free in fluenza vaccines to residents aged ≥65 years considering their high risks in developing life-threatening complications, especially for in fluenza A predominant seasons. Hong Kong is an international subtropical city in Eastern Asia and plays a crucial role in global infectious diseases transmission dynamics via the international air transportation network [3, 4]. We hypothesized that Hong Kong in fluenza surveillance data could provide a signal for in fluenza epidemics in Brisbane [ 4]. This study aims to develop an epidemic forecasting model for influenza A in Brisbane elders, by combining climate variability and Hong Kong in fluenza A surveillance data. Weekly numbers of laboratoryconfirmed influenza A positive isolates for people aged ≥65 years from 2004 to 2009 were obtained for Brisbane from Queensland Health, Australia, and for Hong Kong from Queen Mary Hospital (QMH). QMH is the largest public hospital located in Hong Kong Island, and in fluenza surveillance data from this hospital have been demonstrated to be representative for influenza circulation in the entirety of Hong Kong [ 5]. The Brisbane in fluenza A epidemics occurred during July –September, whereas the Hong Kong in fluenza A epidemics occurred during February –March and May –August.
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The crystal structure of Pb3BiV3O12 was solved using single-crystal X-ray diffraction technique. The compound crystallizes in the cubic system View the MathML source (No. 220) with eulytite structure with a = 10.7490(7) Å, V = 1241.95(14) Å3 and Z = 4. The final R1 value of 0.0198 (wR2=0.0384) was achieved for 359 independent reflections during the structure refinement. The Pb2+ and Bi3+ cations occupy the special position (16c) while the oxygen anions occupy the general position (48e) in the crystal structure. Unlike many other eulytite compounds, all the crystallographic positions are fully occupied. The structure consists of edge-shared Pb/Bi octahedra linked at the corners to independent [VO4]3− tetrahedra units, generating a eulytite-type network in the crystal lattice.
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In this paper we tackle the problem of efficient video event detection. We argue that linear detection functions should be preferred in this regard due to their scalability and efficiency during estimation and evaluation. A popular approach in this regard is to represent a sequence using a bag of words (BOW) representation due to its: (i) fixed dimensionality irrespective of the sequence length, and (ii) its ability to compactly model the statistics in the sequence. A drawback to the BOW representation, however, is the intrinsic destruction of the temporal ordering information. In this paper we propose a new representation that leverages the uncertainty in relative temporal alignments between pairs of sequences while not destroying temporal ordering. Our representation, like BOW, is of a fixed dimensionality making it easily integrated with a linear detection function. Extensive experiments on CK+, 6DMG, and UvA-NEMO databases show significant performance improvements across both isolated and continuous event detection tasks.
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Eriophyid mites (Acari: Eriophyoidea: Eriophyidae: Rhombacus sp. and Acalox ptychocarpi Keifer) are recently-emerged pests of commercial eucalypt plantations in subtropical Australia. They cause severe blistering, necrosis and leaf loss to Corymbia citriodora subsp. variegata (F. Muell.) K.D. Hill & L.A.S. Johnson, one of the region's most important hardwood plantation species. In this study we examine the progression, incidence and severity of these damage symptoms. We also measure within-branch colonisation by mites to identify dispersive stages, and estimate the relative abundance of the two co-occurring species. Rhombacus sp., an undescribed species, was numerically dominant, accounting for over 90% of all adult mites. Adults were the dispersive stage, moving mostly within branches, but 12% of recruitment onto new leaves occurred on previously uninfested branches. Damage incidence and severity were correlated, while older leaves had more damage than younger leaves. "Patch-type" damage was less frequent but was associated with higher mite numbers and damage scores than "spot-type" damage, while leaf discoloration symptoms related mostly to leaf age.
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Biodiversity of sharks in the tropical Indo-Pacific is high, but species-specific information to assist sustainable resource exploitation is scarce. The null hypothesis of population genetic homogeneity was tested for scalloped hammerhead shark (Sphyrna lewini, n = 237) and the milk shark (Rhizoprionodon acutus, n = 207) from northern and eastern Australia, using nuclear (S. lewini, eight microsatellite loci; R. acutus, six loci) and mitochondrial gene markers (873 base pairs of NADH dehydrogenase subunit 4). We were unable to reject genetic homogeneity for S. lewini, which was as expected based on previous studies of this species. Less expected were similar results for R. acutus, which is more benthic and less vagile than S. lewini. These features are probably driving the genetic break found between Australian and central Indonesian R. acutus (F-statistics; mtDNA, 0.751–0.903, respectively; microsatellite loci, 0.038–0.047 respectively). Our results support the spatially homogeneous monitoring and management plan for shark species in Queensland, Australia.
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An attempt is made to study the fracture behavior of ferrocement beams using J-integral and critical crack opening displacement approaches. Ferrocement beams with three different relative notch depths and different percentages of mesh reinforcement were tested in four-point bending (third-point loading). The experimental results were used to evaluate the apparent J-integral and CODc values. Results show that the apparent J-integral does not seem to follow any particular trend in variation with notch depth, but is sensitive to the increase of mesh reinforcement. Hence, the apparent J-integral appears to be a useful fracture criterion for ferrocement. The computed values of CODt are found to be dependent on the depth of notch and, thus, cannot possibly be considered as a suitable fracture criterion for ferrocement.
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Venous thromboembolism (VTE) is the greatest single cause of maternal mortality in pregnant women in developed countries. Pregnancy is a hypercoagulable state and brings about an enhanced risk of deep venous thrombosis (DVT) in otherwise healthy women. Traditionally, unfractionated heparin (UFH) has been used for treatment of DVT during pregnancy. We showed in our observational study that low molecular weight heparin (LMWH) is as effective and safe as UFH in the treatment of DVT during pregnancy. Although DVT during pregnancy is often massive, increasing the risk of developing long-term consequences, namely post-thrombotic syndrome (PTS), only 11% of all patients had confirmed PTS 3 4 years after DVT. In our studies the prevalence of PTS was not dependent on treatment (UFH vs LMWH). Low molecular weight heparin is more easily administered, few laboratory controls are required and the hospital stay is shorter, factors that lower the costs of treatment. Cervical insufficiency is defined as repeated very preterm delivery during the second or early third trimester. Infection is a well-known risk factor of preterm delivery. We found overpresentation of thrombophilic mutations (FV Leiden, prothrombin G20210A)among 42 patients with cervical insufficiency compared with controls (OR 6.7, CI 2.7 18.4). Thus, thrombophilia might be a risk factor of cervical insufficiency possibly explained by interaction of coagulation and inflammation processes. The presence of antiphospholipid (aPL) antibodies increases the risk for recurrent miscarriage (RM). Annexins are proteins which all bind to anionic phospholipids (PLs) preventing clotting on vascular phospholipid surfaces. Plasma concentrations of circulating annexin IV and V were investigated in 77 pregnancies at the beginning of pregnancy among women with a history of RM, and in connection to their aPL antibody status. Control group consisted unselected pregnant patients (n=25) without history of adverse pregnancy outcome. Plasma levels of annexin V were significantly higher at the beginning (≤5th week) of pregnancy in women with aPL antibodies compared with those without aPL antibodies (P=0.03). Levels of circulating annexin V were also higher at the 6th (P= 0.01) and 8th week of pregnancy in subjects with aPL antibodies (P=0.01). Results support the hypothesis that aPL could displace annexin from anionic phospholipid surfaces of syncytiotrophoblasts (STBs) and may exert procoagulant activities on the surfaces of STBs Recurrent miscarriage (RM) has been suggested to be caused by mutations in genes coding for various coagulation factors resulting in thrombophilia. In the last study of my thesis were investigated the prevalence of thrombomodulin (TM) and endothelial protein C receptor polymorphism EPCR among 40 couples and six women suffering RM. This study showed that mutations in the TM or EPCR genes are not a major cause of RM in Finnish patients.
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A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance of b-tagging and the trigger. The physics potential for a variety of interesting physics processes, within the Standard Model and beyond, is examined. The study comprises a series of notes based on simulations of the detector and physics processes, with particular emphasis given to the data expected from the first years of operation of the LHC at CERN.
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The addition reactions of alcohols, ROH (R = CH3, C2H5 n-C3H7, i-C3H7 and t-C4H9), to p-bromophenylisothiocyanate show that the rates decrease in the order, CH3OH> C2H5OH> n-C3H7OH> i-C3H7OH> t-C4H9OH, although the basicities of the alcohols vary in the reverse order. The results indicate the greater importance of steric factors as compared with polar factors. Evidence is also presented for the formation of a complex between the isothiocyanate and the alcohol in the first stage of the addition reaction. In the addition of aniline to substituted phenylisothiocyanates the rate data give a satisfactory linear correlation with Hammett σ constants and the results clearly show that electron-withdrawing groups favour the addition reaction. The addition of aniline to alkyl isothiocyanates have been studied in order to find out the nature of alkyl group interaction in these derivatives. Kinetic studies on the addition of substituted anilines to phenylisothiocyanate show that the rate of reaction increases with the electron-donating ability of the substituents on the aniline as also the basicity of the aniline.
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Active-clamp dc-dc converters are pulsewidth-modulated converters having two switches featuring zero-voltage switching at frequencies beyond 100 kHz. Generalized equivalent circuits valid for steady-state and dynamic performance have been proposed for the family of active-clamp converters. The active-clamp converter is analyzed for its dynamic behavior under current control in this paper. The steady-state stability analysis is presented. On account of the lossless damping inherent in the active-clamp converters, it appears that the stability region in the current-controlled active-clamp converters get extended for duty ratios, a little greater than 0.5, unlike in conventional hard-switched converters. The conventional graphical approach fails to assess the stability of current-controlled active-clamp converters due to the coupling between the filter inductor current and resonant inductor current. An analysis that takes into account the presence of the resonant elements is presented to establish the condition for stability. This method correctly predicts the stability of the current-controlled active-clamp converters. A simple expression for the maximum duty cycle for subharmonic free operation is obtained. The results are verified experimentally.
Resumo:
Tämän tutkimuksen tehtävänä oli selvittää, ovatko sosiaaliset järjestykset Martti Lutherin (1483-1546) mukaan Jumalan erityisesti asettamia. Johdannossa luotiin katsaus moderniin Luther-tutkimukseen. Aikaisemmassa tutkimuksessa havaittiin vallitsevan erimielisyyttä siitä, ovatko sosiaaliset järjestykset Jumalan erityisesti asettamia luomisjärjestyksiä (Schöpfungsordnungen), vai ovatko ne Jumalasta vain välillisesti riippuvaisia, järjen vapaasti muutettavissa olevia sosiaalisen elämän muotoja. Lutherin mukaan ihmisen elämälle on luonteenomaista osallisuus kolmesta sosiaalisesta järjestyksestä. Liittyen keskiaikaiseen käsitykseen Luther puhuu kirkon (ecclesia), perheen (oeconomia) ja yhteiskunnan (politia) järjestyksistä, joista kaksi edellistä olivat olemassa jo alkutilassa. Yhteiskunta sai alkunsa vasta syntiinlankeemuksen jälkeen. Tässä tutkimuksessa ihmisen sosiaalisen elämän tarkastelu rajattiin koskemaan alkutilan sosiaalisia järjestyksiä. Tutkimus suoritettiin kaksiosaisesti. Ensimmäisessä pääjaksossa selvitettiin, minkälainen ontologinen luonne ihmisen sosiaalisella elämällä on. Luther ymmärtää teologian tehtävän kaksiosaisesti Jumalan ja ihmisen tuntemiseksi (cognitio Dei et hominis). Teologia ja erityisesti Raamattu sisältävät Lutherin mukaan luonnon kaikkia aspekteja koskevaa tietoa. Tästä syystä immanenttiin todellisuuteen kuuluvien sosiaalisten järjestysten rajaaminen teologisen tiedon ulkopuolelle ei ole perusteltua. Karl Hollin Luther-tulkinnan tavoin tutkimuksessa havaittiin, että ihmisen ja Jumalan suhde perustuu tahdonyhteyteen, josta seuraa ihmisessä Jumalan sana vaikutuksesta syntyvä usko. Tahdonyhteyden johdosta ihminen tulee osalliseksi Jumalan persoonallisista ominaisuuksista siten, että Jumalan mielenliikkeet heijastuvat ihmisen psyykkisiin ominaisuuksiin. Erityisesti tahdon ja järjen alueilla tapahtuvaa partisipaatiota jumalalliseen luontoon voidaan luonnehtia persoonallis-onttiseksi. Persoonallis-onttinen partisipaatio vaikuttaa sekä ihmisen yksilölliseen elämäntodellisuuteen Jumalan kuvana (imago Dei) että yhteisölliseen elämäntodellisuuteen sosiaalisissa järjestyksissä. Toisessa pääjaksossa havaittiin, että kirkko ja perhe ovat Jumalan erityisillä asetussanoilla perustamia sosiaalisia järjestyksiä, joita voidaan kutsua luomisjärjestyksiksi. Sosiaalisina järjestyksinä kirkko ja perhe eivät kuulu Jumalan inhimilliselle järjelle antaman valtuutuksen (mandatum Dei) piiriin. Saman luonteiseen Jumalan käskyyn (mandatum) perustuva kirkko on järjestys (institutio), joka antaa Jumalan sanan voimalla ihmisen "juopuneelle" mielelle muodon (forma). Kirkko ylläpitää ihmisen persoonallis-onttista partisipaatiota sakramentin ja saarnan välityksellä. Jumalanpalveluksesta Jumala puhuttelee ihmistä inhimillisellä kielellä, antaen muodon sekä ihmisen uskolle että immanentit elämänalueet käsittävälle ulkoiselle kuuliaisuudelle. Sosiaaliset normit syntyvät, kun Jumala puhuttelee ihmistä kirkossa. Perheen havaittiin olevan Jumalan asettama sosiaalinen järjestys (institutio), jonka piiriin kuuluvat miehen ja naisen välisen avioliiton lisäksi taloudellinen toiminta ja kasvatus. Avioliitto on luonteeltaan pyhä ja Jumalan käskyyn perustuva. Perhe mahdollistaa ihmisen lisääntymisen, antaen ulkoiselle työlle ja lasten kasvatukselle sosiaalisen struktuurin. Perheen piiriin kuuluva elämä on riippuvainen kirkosta, sillä jumalanpalveluksen ja saarnaviran välittämä Jumalan sana antaa perheessä tapahtuvalle ulkoiselle kuuliaisuudelle muodon. Perhe on riippuvainen persoonallis-onttisesta partisipaatiosta. Tämä ilmenee myös siten, että langenneessa tilassa perhettä koskeva tieto on riippuvainen teologiasta.
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A simple technique is devised io measure the angles of equilateral (60-deg) prisms, without using the expensive spectrometers, autocollimators, and angle gauges. The method can be extended to unpolished and opaque prisms made out of materials other than glass. (C) 1997 Society of Photo-Optical Instrumentation Engineers.
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Isothermal sections of the phase diagrams for the systems Ln-Pd-O (with Ln = Tb or Er) have been established by equilibration of samples at T = 1223 K, and phase identification after quenching by optical and scanning electron microscopy (OM, SEM), energy dispersive spectroscopy (EDS), and X-ray powder diffraction (XRPD). Two oxide phases were stable along the binary Tb-O: Tb2O3+x, a phase of variable composition, and Tb7O12 at T = 1223K. The oxide PdO was not stable at this temperature. Only one ternary oxide Tb2Pd2O5 was identified in the Tb-Pd-O system. No ternary compound was found in the system Er-Pd-O at T = 1223K. However, the compound Er2Pd2O5 could be synthesized at T = 1075 K by the hydrothermal route. In both systems, the alloys and inter-metallic compounds were all found to be in equilibrium with the lanthanide sesquioxide Ln(2)O(3) (where Ln is either Tb or Er). Two solid-state cells, each incorporating a buffer electrode, were designed to measure the Gibbs energy of formation of the ternary oxides, using yttria-stabilized zirconia as the solid electrolyte and pure oxygen gas as the reference electrode. Electromotive force measurements were conducted in the temperature range (900-1275) K for Th-Pd-O system, and at temperatures from (900-1075) K for the system Er-Pd-O. The standard Gibbs energy of formation Delta(f)G(m)degrees,, of the inter-oxide compounds from their component binary oxides Ln(2)O(3) and PdO are represented by equations linear in temperature. Isothermal chemical potential diagrams for the systems Ln-Pd-O (with Ln = Tb or Er) are developed based on the thermodynamic information. (C) 2002 Elsevier Science Ltd. All rights reserved.