Search results for " Force"
showing 10 items of 2250 documents
Implant-supported fixed prostheses in a Patient with Osteogenesis Imperfecta : a 4-year follow-up
2017
Osteogenesis Imperfecta (OI) is a rare autosomal dominant connective tissue disorder in wich, the bone quality and density is affected. OI includes some metabolic disorders and have a wide range of clinical presentations. In Osteogenesis Imperfecta bone has a very low density and it is a disorder currently treated with bisphosphonates. Quality and quantity of bone is important for establishment of osseointegration in dental implants. There are few reported cases in the literature. This is a case report of a 61 year-old man with grade IV OI, rehabilitated with implant-supported fixed prostheses in the posterior right and left mandible, whithout bone grafts. At the 4-year follow-up, clinical …
Elementary Newtonian Mechanics
2010
This chapter deals with the kinematics and the dynamics of a finite number of mass points that are subject to internal, and possibly external, forces, but whose motions are not further constrained by additional conditions on the coordinates. Constraints such as requiring some mass points to follow given curves in space, to keep their relative distance fixed, or the like, are introduced in Chap. 2. Unconstrained mechanical systems can be studied directly by means of Newton’s equations and do not require the introduction of new, generalized coordinates that incorporate the constraints and are dynamically independent. This is what is meant by “elementary” in the heading of this chapter — thoug…
Diritti, sicurezza, solidarietà e responsabilità nella protezione della persona migrante
2018
1. Uno sguardo d’insieme. 2. Dopo Lisbona: le competenze dell’UE e la Carta dei diritti dinanzi alle crisi migratorie e all’onda lunga del populismo. 3. Protezione della persona migrante, Costituzione e decretazione di urgenza. 4. Solidarietà e diritti nella prospettiva costituzionale: uguaglianza, bisogni primari e contenuto essenziale
Long-range cohesive interactions of non-local continuum faced by fractional calculus
2008
Abstract A non-local continuum model including long-range forces between non-adjacent volume elements has been studied in this paper. The proposed continuum model has been obtained as limit case of two fully equivalent mechanical models: (i) A volume element model including contact forces between adjacent volumes as well as long-range interactions, distance decaying, between non-adjacent elements. (ii) A discrete point-spring model with local springs between adjacent points and non-local springs with distance-decaying stiffness connecting non-adjacent points. Under the assumption of fractional distance-decaying interactions between non-adjacent elements a fractional differential equation in…
Port–City Relationship and the Environment: Literature Survey and Methodological Approach for Project Appraisal in Presence of Environmental External…
2015
AbstractIn times of increasing environmental awareness, the port–city relationship has gained new meaning because ports have been seen as the origin of both negative and positive externalities affecting public welfare. While the former are the result of port expansion, the latter are the result of transforming obsolete port areas into recreational facilities. Therefore, to support effective policymaking, this paper considers the following question: What is the scope of economic valuation of these externalities in the context of port-project appraisal? Considering their nonmarket nature, which makes economic valuation more difficult, a contingent valuation method is introduced as an economic…
The nonmarket benefits of redeveloping dockland areas for recreational purposes: the case of Castellón, Spain
2003
As a consequence of the decline of central harbour sites and the relocation of port activities to the outskirts of cities, today waterfront redevelopment has become a key issue in the urban revitalisation policies of port cities. Although we are aware that city-port regeneration has strong links with the real estate market, our purpose here is very different. In particular, the contingent valuation method (CVM) has been applied in order to obtain the nonmarket benefits of the environmental and urban improvements derived from redeveloping some port-related areas for recreational and leisure purposes in the city of Castelloèn, Spain. To date, no previous study has attempted to apply this meth…
Can hydrophobic interactions be correctly reproduced by the continuum models?
1996
The ability of the continuum models to describe hydrophobic interactions is investigated. In this work we have studied the interactions between two methane molecules in aqueous solution by means of a continuum model. The resulting potential of mean force is in good agreement with those obtained using Monte Carlo and molecular dynamics techniques. The three energy contributions appearing in the continuum energy partition (electrostatic, dispersion−repulsion, and cavitation) have been analyzed. The cavitation free energy plays the most important role of the three, determining the existence of an energy barrier between the contact minimum and the separated methane monomers. This barrier, which…
Optimal damping coefficient for a class of continuous contact models
2020
AbstractIn this study, we develop an analytical formula to approximate the damping coefficient as a function of the coefficient of restitution for a class of continuous contact models. The contact force is generated by a logical point-to-point force element consisting of a linear damper connected in parallel to a spring with Hertz force–penetration characteristic, while the exponent of deformation of the Hertz spring can vary between one and two. In this nonlinear model, it is assumed that the bodies start to separate when the contact force becomes zero. After separation, either the restitution continues or a permanent penetration is achieved. Therefore, this model is capable of addressing …
Metal/Semiconductor Barrier Properties of Non-Recessed Ti/Al/Ti and Ta/Al/Ta Ohmic Contacts on AlGaN/GaN Heterostructures
2019
This paper compares the metal/semiconductor barrier height properties of non-recessed Ti/Al/Ti and Ta/Al/Ta contacts on AlGaN/GaN heterostructures. Both contacts exhibited a rectifying behavior after deposition and after annealing at temperatures up to 550 °
Constant Power Solution of Hill’s Equation
2019
This book deals with constant power solution of Hill’s equation. This book covers key areas of muscle mechanics; muscle force; muscle power; force-velocity relationship; Hill’s equation; arm movement; leg movement etc. This book contains various materials suitable for students, researchers and academicians of this area.