La dégradation accélérée des membranes conductrices protoniques en pile est en partie due à une oxydation induite par la production d'H2O2. Cette étude présente une stratégie originale de stabilisation chimique d'une matrice de sPEEK par l'inclusion de nano-charges stabilisantes. Quatre nano-charges ont été préparées par fonctionnalisation de nanoparticules de silice avec des fonctions chimiques organosoufrées (disulfure, tétrasulfure et thiourée). Un protocole spécifique de mise en forme des membranes hybrides a permis d'obtenir des composites présentant des propriétés mécaniques et une conductivité protonique compatibles avec l'application pile. Les fonctions polysulfures permettent de ralentir la dégradation de la matrice de sPEEK durant l'étape de mise en œuvre et d'augmenter sa conductivité au cours d'un vieillissement ex-situ (H2O2). En présence de fonctions tétrasulfures, la membrane sPEEK ne se dégrade pas durant un test de 1200h en OCV à 70°C et 100%HR. / One of the origins of the accelerated aging of proton exchange membranes used in Fuel Cells is the oxidation induced by H2O2 formation. This work concerns the development of a new way to chemically stabilize a sPEEK membrane by the addition of stabilizing nano-fillers. Four fillers were synthesized by grafting organosulfur functions (disulfide, tetrasulfide and thiourea) onto silica nanoparticles. A specific protocol to prepare hybrid membranes led to materials with suitable mechanical properties and proton conductivity for fuel cells application. Polysulfides allow a significant decrease of the matrix degradation occurring during membrane processing and also a large increase of the proton conductivity of this matrix during ex-situ aging tests (H2O2). A membrane containing tetrasulfide nano-fillers could withstand 1200h in OCV condition at 70°C and 100%RH, without showing any sign of degradation.

Cette thèse concerne des systèmes hybrides et le théorème des petits-gains. Plus précisément, d'une part, nous avons calculé les lois de commande hybrides pour les systèmes non-linéaires lesquels les techniques de synthèse par backstepping ne s'applique pas et nous avons réussi à combiner les lois de commande locales et globales pour la stabilisation d'un ensemble «proche» de l'origine. La seconde contribution est sur ​​le théorème des petits-gains, en traitant avec des systèmes pour lesquels les conditions des petits-gains sont satisfaites seulement au niveau régional. Nous avons réussi à combiner ces conditions régionales pour le petit-gain pour la stabilité asymptotique et pour la presque stabilité asymptotique globale. / This theses concerns hybrid systems and small gain theorems. More precisely, firstly we computed hybrid stabilizers for nonlinear control systems for which the backstepping techniques do not apply, and we succeeded to combine local feedback laws and global controllers stabilizing a set "close" to the origin. The second contribution is on small gains theorem, by dealing with systems for which small gains conditions are satisfied only regionally. We were able to combine such region-dependent small-gain conditions for the global asymptotic stability and for the almost global asymptotic stability.

Building rammed earth structures provides a sustainable alternative to concrete. As a building material, rammed earth exhibits very varied physical and material properties depending on the proportion of constituting soil types. When very sandy soil is used in rammed earth production, the properties are different from when a clayey soil is used. This variability can be seen as a very great advantage in the use of rammed earth as a building material. Builders are able to adjust specific properties by changing mix proportions to obtain a desirable balance in the characteristics of the resulting rammed earth structure. This research work looks at selected mechanical and physical properties of different mixes of rammed earth. It describes typical range of values in density, thermal conductivity, ultrasonic pulse velocity, water ingress and compressive strength. It examines how these factors interrelate in the same soil mixes. Samples were prepared by blending various soil types in specific proportions to ensure that each definition of soil grade is as specific as possible. Unstabilised rammed earth was tested as was cement stabilised rammed earth. Rammed earth was tested at various levels of stabilisation and it was discovered that higher rates of stabilisation was not always beneficial to every material property. The research also looked into the potential disposal of waste materials in rammed earth. As rammed earth is a monolithic material that largely remains undisturbed throughout its life span, it was suggested that waste materials could be stored in an inert form inside of rammed earth rather than dumping it in otherwise agricultural landmass. Pulverised Fuel Ash and Palm Kernel Shells were identified as wastes to be disposed in rammed earth. Pulverised Fuel Ash, a by-product of industrial furnace is found in abundance in developed countries that burn carbonaceous materials in power plants. Disposals have been seen as a problem as only a small proportion of high loss on ignition (LOI) Pulverised Fuel Ash has found application. Palm Kernel Shell is a by-product of the oil palm industry and is currently a menace in many developing countries that need to dispose large quantities of the shell in landfills. At an early stage of the research, experimental trial runs quickly showed that these supposedly waste materials had a positive effect on some of the material properties of the rammed earth walls they were made into. This research effort evolved to look into exploiting these materials to improve the physical and material property of rammed earth and to suggest their effect on stabilised and unstabilised rammed earth. The extent to which these materials could be useful and the level at which diminishing returns set in was also investigated. It was discovered that soil mixes that would otherwise not be considered suitable for use in rammed earth wall production can now be utilised as their characteristics can be improved on simply by adding Pulverised Fuel Ash or Palm Kernel shell in the right proportion. Incorporating Pulverised Fuel Ash in rammed earth resulted in increased compressive strength. Palm Kernel shell improved thermal properties without compromising compressive strength.

Les douleurs lombaires représentent l'une des premières causes d'intervention chirurgicale dans le monde, et requièrent le recours à une instrumentation du rachis complémentaire pour environ 1% des patients. La technique instrumentée standard est l'arthrodèse ; elle consiste en l'immobilisation des vertèbres adjacentes par un système composé de vis pédiculaires et de tiges. Les résultats cliniques sont généralement satisfaisants. Cependant, des cas de complications subsistent, en particulier la dégénérescence du segment adjacent pouvant entraîner une reprise chirurgicale. Pour répondre à ce problème, les implants dits « stabilisation dynamique » ont été conçus avec pour objectif de maintenir une mobilité au niveau instrumenté afin de ne pas sur-contraindre les structures environnantes. Cette étude consiste en l'évaluation clinique et biomécanique d'un de ces implants. Tout d'abord, nous avons mené une campagne d'essais de caractérisation mécanique de l'implant isolé afin de connaître précisément ses propriétés et de pouvoir le modéliser de façon fidèle et validée. Un travail clinique rétrospectif a ensuite été réalisé pour quantifier les résultats obtenus et proposer un protocole d'étude prospective qui réponde aux contraintes cliniques et aux exigences scientifiques actuelles. Une campagne d'essais in-vitro sur segment lombaire a ensuite été menée pour compléter notre connaissance du comportement biomécanique du rachis instrumenté. Ceci nous a permis de valider une modélisation en éléments finis du rachis instrumenté utilisé notamment pour étudier l'influence du design de l'implant ainsi que des gestes réalisés lors de la chirurgie. / Back pain is one of the first causes of surgical intervention in the world and instrumentation is needed for about 1 patient out of 100 . Fusion is the gold standard for instrumented surgery and consists in fixation of two adjacent vertebra together with pedicular screws and rigid rods. Clinical outcomes of fusion are satisfactory but some cases of adverse events remain such as adjacent segment degeneration sometimes leading to revision surgery. Dynamic stabilization devices have been proposed to tackle this issue with the objective of maintaining motion at the instrumented level and thus limiting the surrounding structure overloading. This work aims at assessing one dynamic stabilization device. We first performed mechanical testing on the device to better understand its functioning and come up with a detailed and validated model. Then a retrospective clinical work has been conducted to lay out the clinical performances of the device and propose a prospective study design to answer clinical and scientific requirements. A biomechanical in-vitro testing campaign has been set up to increase our knowledge about the behaviour of the instrumented spine. This enabled us to validate a finite elements model then used for the study of the influence of several design parameters but also of several choices made during the surgery.

Textile UV-radiation sensors has lately been introduced to the field of smart textiles. Inkjet printing has been used as means of application due to the effective and resource efficient process. UV-LED radiation curing has been used in combination with inkjet printing in favour of low energy requirements, solvent free solution and reduced risk of clogging in the print heads. The problems arising when exposing photochromic prints to UV-radiations are that oxygen inhibition during the curing and photo-oxidation in the print reduces the prints ability to develop colour. It is the oxygen in the air in combination with UV-radiation that gives the photo-oxidating behavior. The aim of the study is to with the aid of physical protection reduce the effect of oxygen inhibition and photo-oxidation in the prints. Three types of physical treatments were used, wax coating, protein based impregnation and starch based impregnation. Treatments were applied before curing as well as after curing and the colour development after activation during 1 min of UV-radiation was measured with a spectrophotometer. Multiple activations were also tested to see how the treatments affected the fatigue behaviour of the prints over time. The aim was to have as high colour development as possible reflecting reduced oxygen inhibition and photo-oxidation. Results showed significantly higher colour development for samples treated with wax and whey powder before curing, but reduced colour development for amylose impregnation. Over time whey powder before curing showed highest colour development due to highest initial colour development. Lowest fatigue was seen for washed samples containing the chemical stabiliser HALS, showing an increased colour development. In reference to earlier studies the protective properties of wax and whey powder is due to their oxygen barrier properties protecting the print. The tested treatments have shown that it is possible to reduce the effect of photo-oxidation during curing leading to prints giving higher colour development. This gives a great stand point when improving existing and future application of photochromic prints on textiles.

Au cours de dix dernières années la science aux attoseconde ou Physique au champ-fort a été l’objet d’un fort développement. La production d’impulsions laser énergétiques de courte durée à haute cadence et stabilisées en CEP constitue la première étape pour accéder aux dynamiques ultra-rapides caractérisant l’interaction de la matière avec une source de lumière cohérente, intense et ultra-rapide. Le travail de cette thèse consiste à améliorer globalement les performances d’un système laser Ti:Sa à haute cadence optimisé pour la génération des impulsions attoseconde. Nous avons développé une nouvelle configuration de cavité régénérative fonctionnant à 10 kHz qui permet une meilleure gestion des effets thermiques dans le cristal. En sortie de l’amplificateur les impulsions atteignent des valeurs de puissance de 5 W en bande étroite (35 fs), ou 2.7 W en bande spectrale large permettant une compression des impulsions proche de 17 fs. La CEP des impulsions en sortie d’amplificateur a été stabilisée ; le bruit résiduel mesuré tir-à-tir est de 210 mrad pendant trois heures.L’amplificateur peut supporter également le fonctionnement en mode accordable, en sélectionnant des spectres de 30 à 40 nm de largeur à mi-hauteur et en accordant leur longueur d’onde centrale dans une gamme de 80 nm autour de 800 nm. Nous avons conçu et mis en fonctionnement un amplificateur multi-passages non-cryogéné à imagerie par lentille thermique pour accroître la puissance des impulsions jusqu’à 10 W à une cadence de 1 kHz. Le régime de forte saturation d’amplificateur garantit une variation négligeable (±3% pic à pic) de la puissance des impulsions en sortie du module, face à une variation importante de la puissance en entrée (±25% pic à pic) sur la bande spectrale accordable. L’amplification peut encore être plus importante grâce à une ligne d’amplification à refroidissement cryogénique, qui permet d’atteindre des puissances au niveau TW, à la cadence de 1 kHz, tout en maintenant un régime de courte durée (17.5 fs) et stabilité en CEP (350 mrad de bruit résiduel tir-à-tir). Nous proposons aussi une étude des sources de bruit de CEP dans les modules hautement dispersifs: nous avons conçu une nouvelle approche numérique sur la base d’un logiciel de tracé de rayon commercial (Zemax) pour évaluer les variations de CEP dans les modules contenant réseaux de diffraction. / The last decade has seen a lot of progress in attosecond science or in strong field physics. Generating energetic, few-cycle laser pulses with stabilized Carrier-Envelope Phase at high repetition rate constitutes the first step to access the ultra-fast dynamics underlying the interaction of matter with intense, ultrashort coherent light source. The work of this thesis consists in globally improving the performances of a high repetition rate Ti:Sa laser system optimized for attosecond science. We present an original 10 kHz Ti:Sa CPA laser based on an newlydesigneddouble-crystal cavity for thermal lensing management. The amplifier delivers up to 5 W in narrow band mode (35 fs pulses), or 2.7 W in broad band mode, supporting 17 fs pulses after temporal compression. We demonstrate shot-to-shot CEP stabilization with a remaining noise of 210 mrad over three hours at the front-end output. In parallel to the short pulse duration operation mode, it is possible to use the front end in a wavelength tunability mode within a 80 nm range around 800 nm, with a resolution of 1 nm and 30 to 40 nm of bandwidth. We designed and demonstrated a complete water-cooled lens-less multipass amplifier using thermal lensing for modeadaptation boosting the pulse energy up to 10mJ at 1 kHz repetition rate (up to 10 W). The saturation regime of the amplifier ensures negligible variation (±3% peak to peak) of the output power for significant variation of the input power (±25% peak to peak) over the tunability range. The energy scalability of the front-end is demonstrated by coupling its output to cryogenically cooled amplifier, delivering 1 kHz, TW-class pulses at 17.5 fs and CEP stabilized with a residual noise of 350 mrad. A study of CEP noise sources in high dispersive module is also addressed, proposing a numerical approach based on a commercial ray-tracing software (Zemax) for predicting CEP fluctuation in grating based modules.

Dans cette thèse, nous étudions les théories étroitement liées du contrôle, de la stabilisation et de la propagation des singularités, pour des équations aux dérivées partielles dispersives linéaires et non-linéaires. Les résultats principaux proviennent des travaux de l’auteur:[1] Zhu, H., 2016. Stabilization of damped waves on spheres and Zoll surfaces of revolution. ESAIM : Control, Optimisation and Calculus of Variations (ESAIM: COCV), à paraître.[2] Zhu, H., 2017. Control of three dimensional water waves. arXiv preprint arXiv:1712.06130.[3] Zhu, H., 2018. Propagation of singularities for gravity-capillary water waves. arXiv preprint arXiv:1810.09339.Dans [1], nous avons étudié la stabilisation des ondes amorties sur les surfaces de révolution de Zoll. Nous avons donné un exemple où la région d’amortissement est à la limite de la condition du contrôle géométrique, alors que les ondes amorties présentent une décroissance exponentielle uniforme de l’énergie. Cet exemple généralise un résultat de Lebeau. Dans [2], nous avons étudié la contrôlabilité du système des ondes de surface avec tension superficielle. Nous avons démontré, en dimensions arbitraires, la contrôlabilité exacte pour des petites données spatialement périodiques à condition du contrôle géométriques. Ce résultat généralise le travail de Alazard, Baldi et Han-Kwan en dimension deux. Dans [3], nous avons étudié la propagation des singularités pour des ondes de surface avec tension superficielle. Nous avons défini le front d’onde quasi-homogène, généralisant le front d’onde de Hörmander et le front d’onde homogène de Nakamura et démontré des résultats de propagation des fronts d’onde quasi-homogènes par le système des ondes de surface avec tension superficielle. Comme corollaires, nous avons obtenu des effets régularisants locaux et micro-locaux pour les données initiales présentant une décroissance spatiale suffisante. / In this thesis, we study the closely related theories of control, stabilization and propagation of singularities for some linear and nonlinear dispersive partial differential equations. Main results come from the author’s works:[1] Zhu, H., 2016. Stabilization of damped waves on spheres and Zoll surfaces of revolution. ESAIM: Control, Optimisation and Calculus of Variations (ESAIM: COCV), to appear.[2] Zhu, H., 2017. Control of three dimensional water waves. arXiv preprint arXiv:1712.06130.[3] Zhu, H., 2018. Propagation of singularities for gravity-capillary water waves. arXiv preprint arXiv:1810.09339.In [1] we studied the stabilization of the damped wave equation on Zoll surfaces of revolution. We gave an example where the region of damping is at the borderline of the geometric control condition, yet the damped waves exhibit a uniform exponential decay of energy, generalizing an example of Lebeau.In [2] we studied the controllability of the gravity-capillary water wave equation. Under the geometric control condition, we proved in arbitrary spatial dimension the exact controllability for spatially periodic small data. This generalizes a result of Alazard, Baldi and Han-Kwan for the 2D gravity-capillary water wave equation.In [3] we studied the propagation of singularities for the gravity-capillary water wave equation. We defined the quasi-homogeneous wavefront set, generalizing the wavefront set of H¨ ormander and the homogeneous wavefront set of Nakamura, and proved propagation results for quasi-homogeneous wavefront sets by the gravity-capillary water wave equation. As corollaries, we obtained local and microlocal smoothing effects for gravity-capillary water waves with sufficient spatial decay.

Cette thèse aborde la problématique de la restauration d’images 3D de noyaux cellulaires fluorescents issues de la microscopie 2-photons à balayage laser d’animaux observés in vivo et in toto au cours de leur développement embryonnaire. La dégradation originale de ces images provient des limitations des systèmes optiques, du bruit intrinsèque des systèmes de détection ansi que de l’absorption et la diffusion de la lumière dans la profondeur des tissus. A la différence des propositions de “débruitage” de l’état de l’art, nous proposons ici une méthode qui prend en compte les particularités des données biologiques. Cette méthode, adaptation à la troisième dimension d’un algorithme utilisé dans l’analyse d’image astronomique, tire parti de connaissances a priori sur les images étudiées. Les hypothèses émises portent à la fois sur la détérioration du signal par un bruit supposé Mixe Poisson Gaussien (MPG) et sur la nature des objets observés. Nous traitons ici le cas de noyaux de cellules embryonnaires que nous supposons quasi sphériques.L’implémentation en 3D doit prendre en compte les dimensions de la grille d’échantillonnage de l’image. En effet ces dimensions ne sont pas identiques dans les trois directions de l’espace et un objet sphérique échantillonné sur cette grille perd cette caractéristique. Pour adapter notre méthode à une telle grille, nous avons ré-interprété le processus de filtrage, au coeur de la théorie originale, comme un processus physique de diffusion. / In this this document, we present a method to denoise 3D images acquired by 2-photon microscopy and displaying cell nuclei of animal embryos. The specimens are observed in toto and in vivo during their early development. Image deterioration can be explained by the microscope optical flaws, the acquisition system limitations, and light absorption and diffusion through the tissue depth.The proposed method is a 3D adaptation of a 2D method so far applied to astronomical images and it also differs from state-of the of-the-art methods by the introduction of priors on the biological data. Our hypotheses include assuming that noise statistics are Mixed Poisson Gaussian (MPG) and that cell nuclei are quasi spherical.To implement our method in 3D, we had to take into account the sampling grid dimensions which are different in the x, y or z directions. A spherical object imaged on this grid loses this property. To deal with such a grid, we had to interpret the filtering process, which is a core element of the original theory, as a diffusion process.

In the thesis according to the award (the design and assessment of the basic elements of container crane, design and calculation drives of bridge and cats, including relevant drawings) developed completely. Assessment of the basic elements of container crane is carried out according to CSN 27 0103 Design of steel structures and cranes CSN 73 1401 Design of steel structures. It is designed and calculated drives as a bridge crane and drive cats. The thesis is processed into different units according to the award.

<p>Predmet izučavanja ove disertacije je ispitivanje mogućnosti imobilizacije&nbsp;toksičnih metala u sedimentu primenom imobilizacione tehnike&nbsp;solidifikacije/stabilizacije portland cementom, kalcijum-oksidom, prirodnim zeolitom,&nbsp;letećim pepelom, kaolinitom, montmorilonitom, i različitim sme&scaron;ama ovih agenasa&nbsp;kao i određivanje njihove efikasnosti u zavisnosti od brojnih faktora. Efikasnost&nbsp;imobilizacionih postupaka praćena je kori&scaron;ćenjem tzv. testova izluživanja, odnosno&nbsp;određivanjem koncentracije metala koji su u toku određenog vremena iz imobilisane&nbsp;faze pre&scaron;li u mobilnu fazu gde se smatraju potencijalno opasnim i biodostupnim.&nbsp;Krajnji cilj svakog testa izluživanja je mogućnost procene adekvatnosti primene&nbsp;određene imobilizacione, odnosno remedijacione tehnike. Efikasnost imobilizacionih&nbsp;postupaka zavisi i od određenih osobina: pH rastvora, dodatka imobilizacionog agensa&nbsp;&scaron;to je istraživanjem ispitano. Na osnovu ovog testa, odnosno &nbsp; odnosa kumulativne&nbsp;frakcije metala koja je oslobođena iz imobilizacione sme&scaron;e u mobilnu fazu i vremena&nbsp;određen je tip mehanizma koji omogućava transport metala &nbsp;(spiranje, difuzija,&nbsp;rastvaranje). Takođe su određeni i i parametri (koeficijenti difuzije, indeksi&nbsp;izlužljivosti) koji&nbsp; će poslužiti za ocenu efikasnosti prethodno primenjenih&nbsp;imobilizacionih tehnika. Primenjeni su i modifikovani testovi izluživanja sa ciljem &scaron;to&nbsp;bolje simulacije realnih uslova. U modifikovanim testovima izluživanja kori&scaron;ćen je&nbsp;rastvor sa pH 3,25 da bi se simulirali uslovi koji opona&scaron;aju kisele ki&scaron;e, odnosno uslovi&nbsp;u realnom sistemu. Takođe je kor&scaron;ćen i rastvor huminskih materija sa ciljem&nbsp;simulacije uslova velikog organskog opterećenja do kojeg bi moglo doći u slučaju&nbsp;akcidentnih situacija (na primer poplava) i generalno uslova koji se stvaraju u &nbsp;prirodi&nbsp;pri raspadanju organskog materijala (li&scaron;će, trava, itd.). Rezultati dobijeni simulacijom&nbsp;ovih uslova će dalje omogućiti modelovanje pona&scaron;anja metala u smislu dugoročnog&nbsp;&quot;izluživanja&quot; iz tretiranog sedimenta kao i procenu najefikasnijih agenasa &nbsp; za&nbsp;imobilizaciju različitih metala u sedimentu. Na osnovu dobijenih rezultata, zaključeno&nbsp;je da su optimalni agensi za imobilizaciju metala u sedimentu sme&scaron;a cementa i kreča&nbsp;(5% cementa i 10% kreča), sme&scaron;a montmorilonita i kreča (30% montmorilonita i 10%&nbsp;kreča), leteći pepeo (30%) i zeolit (30%). U ovim sme&scaron;ama dominantan mehanizam&nbsp;izluživanja je difuzija, a ove sme&scaron;e se mogu smatrati inertnim otpadom po svim&nbsp;ispitivanim kriterijumima. Ovi rezultati se mogu upotrebiti za projektovanje i&nbsp;izgradnju pilot postrojenja na kome bi se ispitala efikasnost ovih agenasa za&nbsp;remedijaciju sedimenta u realnim uslovima. Dobijeni podaci su neprocenjivi sa&nbsp;aspekta ekonomski i ekolo&scaron;ki prihvatljivog upravljanja sedimentom.</p> / <p>This work is concerned with exploring the possibilities of immobilization of toxic&nbsp;metals in sediments using solidification/stabilization as imobilization technique and&nbsp;using Portland cement, calcium oxide, natural zeolite, flying ash, kaolinite, montmorilonite, and various mixtures of these agents and determine their&nbsp;effectiveness depending on many factors. Performance of imobilization procedures&nbsp;was followed by the use of so-called leaching tests and determination of the metals&nbsp;concentration that are within a specified interval of time leached from the immobile phase and as such can be considered potentially hazardous and bioavailable. The ultimate goal of every leaching test is to assess the adequacy of the possibility of applying certain imobilization or remediation technique. Performance of imobilizaction procedures depends on certain characteristics: pH of solution, additon of imobilization agent, etc. Based on this test, ie relation between the cumulative fraction of metal leached from imobilization mixture and time, the type of leaching mechanism that allows the transport of metals (wash-off, diffusion, dissolution) was determined. Other parameters which will serve for evaluating the efficiency of the previously applied imobilization techniques (diffusion coefficients, leaching indices) were also determined. Modified leaching tests were applied with the aim of better simulation of real conditions on the field. In the modified leaching tests the solution with pH 3.25 was used to simulate conditions that mimic acid rain and conditions in the real system. The humic acid solution was also used with the aim to simulate high organic loads which could occur in the case accident situation (eg floods) and the general conditions that are created in naturewhen decaying organic material (leaves, grass, etc.). The results obtained by simulating these conditions will enable the modeling of behavior of metals in terms of long-term leaching period from the treated sediment and assess the most effective agents for the immobilization of various metals in the sediments. Based on these results, it was concluded that the optimal agents for immobilization of metals in the sediment mixture of cement and lime (5% cement and 10% lime), a mixture montmorilonite and&nbsp; lime (30% montmorilonite and 10% lime), fly ash (30%) and zeolite (30%). In these mixtures dominant leaching mechanism is diffusion, and these mixtures can be considered as inert waste by all tested criteria. These results can be used to design and builda pilot plant in which order to evaluate the effectiveness of these agents for remediation of sediment in real &nbsp;terms. The obtained data are invaluable from the aspect of economic and ecologically acceptable management of sediment.</p>