Abstract. In this work is indicated how it could be possible to evaluate the limit stress of the thermo-elastic phase of deformation by thermo-analysing the surface of the specimen during a static traction test. Adding the temperature curve measured on a small area of the surface (the hottest) to the classic stress-strain curve, it is possible to evaluate a limit temperature T 0 coincident with the beginning of the non linear trend of the curve. The corresponding stress value is coincident with the fatigue limit of the analyzed component. As an example, the results of traction tests performed on two notched specimens, where the change of linearity in the temperature curve during static traction test was evident, are reported. The corresponding value of stress was a good approximation of the fatigue limit for R = -1, determined by the conventional method. The aim of the reported examples in this paper must be interpreted as support to the basic principle of the method and not as the results of a complete experimental planning of which we will comment in an another occasion.1 Nomenclature E l energy required for fatigue fracture ĭ l integral of a surface point temperature, proportional to E l , at fatigue fracture ı stress ı 0 fatigue limit for R = -1 (limit stress above which some crystal is plasticized)) ı i minimum stress ı s maximum stress ı m mean stress ı p plastic stress ı 0,2 yield stress ı r fracture strength/original cross sectional area and t r is the test time with thermo plastic behaviour f loading frequency R stress ratio İ strain İ 0 strain corresponding to ı 0 a

A simplified two-layered zonal model coupled with a network model is developed to predict the smoke movement in vertical shafts such as stairwells and elevator shafts during a high-rise fire. The main governing equations of smoke movement consist of conservation equations of mass and energy, convective heat transfer, radiative heat transfer and momentum transfer. It is essential to consider the temperature distribution in the vertical shaft, the buoyancy-induced flow and heat transfer results of strong upward forces known as "stack effect". This model is aiming at predicting the smoke movement in order to develop a successful fire protection plan and improve the occupants' safety in the event of fire. The model analysis yields three main measures to improve safety on the upper floors, including increasing the vent size on the top of the elevator shaft, pressurizing the floors except the fire floor and reducing the gaps around elevators. These measures can also raise the location of neutral pressure plane (NPP) which is critical for upper floor smoke controls. Ultimately, the location of NPP can be raised above the total height of structure, thus the smoke will be kept inside and exhausted out of the elevator shaft.

Abstract. Several surgical techniques like are today available in order to recovery large bone defects of the jaw. Aim of the surgeon is to obtain a good tridimensional volume to place dental implant and to recovery the patient's aesthetics and function. Several prosthetic solution were considered for prosthetic rehabilitation. However after a bone graft surgery Toronto screwed prosthesis on dental implants, following Branemark intuitions, was considered the better prosthetic rehabilitation solution. According to Wölff, the dental implants osteointegration is related to the strengths directed to mandibular bone. Our investigation's aim is to underline through FEM analysis the stress over the prosthetic elements and over bone surface in order to help the surgeon choice about the dental implant positioning, and at the same time reducing the bone trauma on the patients.