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In this paper, Saint-Venant end effects for plane deformations of transversely isotropic piezoelectric materials are investigated. The stress decay rates in linear piezoelectric strips that are traction free with two kinds of electrical boundary conditions are considered. The characteristic equations for decay rate are obtained for symmetric and antisymmetric deformations. Numerical values are given for the roots with the smallest positive real part, which are associated with the slowest decay. Saint-Venant end effects of piezoelectric materials of crystal class 6mm penetrate much further into strip than those of elastic isotropic materials.

We have been developing an advanced general-purpose computational mechanics system, named ADVENTURE, which is designed to be able to analyze a three dimensional finite element model of arbitrary shape over 100 million Degrees Of Freedom (DOF) mesh. The one of main process modules for solid analysis, named ADVENTURE_Solid, is based the hierarchical domain decomposition parallel algorithm and employs the balancing domain decomposition as a solution technique for linearized equations. The ADVENTURE_Solid has been successfully implemented on a single PC, PC clusters and MPPs with high parallel performances. Since the software has become a quite large system, it is not easy to install or operate the system on parallel machines by users. In this paper, to operate such a system from a client PC through the network, the Web-based CAE system is developed.

Experimental works using a drop weight impact test method have been performed on a circular sheet specimen to evaluate and to characterize the impact resistance of the sheet-type plastic components designed for automotive wheel covers. Evaluation has been conducted for a set of engineering plastics: polycarbonate (PC), acrylonitrile-butadiene-styrene (ABS) and their blend (PC/ABS). The testing results showed that the PC/ABS blend specimens failed in brittle manner under higher impact speeds with very few of whitening zones. Secondary cracks captured perpendicular to fracture surface were also found in the mid-plane of the scattered PC/ABS blend specimens. Investigation is then focused on this blend and the testing results describe that impact resistance of the specimen made of this alternative material is determined by ABS not by PC. Combination of structures between PC and ABS through the thickness in the core due to their immiscibility was observed by scanning electron microscope (SEM) on the etched PC/ABS specimen. This latter result well correlates the results obtained from the testing. It therefore reveals that immiscibility between PC and ABS in the blend plays an important role in determining the impact resistance of the components. This paper also presents simulative results of the test obtained from a FEA work by introducing a 3D- layered finite element (FE) model of the PC/ABS specimen to take into account effect of a layer in the core on the behavior of the blend.

This paper presents a review of the methods for seismic vulnerability assessment, together with an experimental method based on shaking table testing. This method is applied to a Portuguese masonry building typology with stone walls and timber floors, subjected to increasing earthquake damage. Traditional-like materials and techniques are used in the building. The vulnerability curves are presented and the damage indicator is correlated with the crack patterns and EMS 98.

Since earthquakes such as Northbridge (1994) and Kobe (1995) gave the impetuous for the development of performance-based design methods, engineers have been strenuously working to the improvement of the seismic behaviour of structures; in fact, high ductility frames, as well as damping and isolation systems, are nowadays common practice in seismic prone areas. Heritage buildings constitute an odd case: many historic centres are still considerably affected by seismic events (L’Aquila, 2009) due to the lack of a methodical retrofit and this, where applied, is still largely based on the increase of stiffness and capacity, without the due care for precious finishings. In order to address the lack of specific passive systems for heritage buildings, the authors have developed two typologies of dissipative devices that can be integrated in traditional steel anchors and installed within the masonry at the joints of perpendicular walls, where out-of-plane mechanisms are likely to form due to poor quality connections. Both prototypes, one based on the plasticity of steel, the other relying on friction, were tested as isolated elements in pseudo-static regime for proofing and fine tuning, and in a dynamic range typical of the seismic frequency content to validate the stability of dissipative loops. The paper focuses on pull-out tests aimed to analyse the behaviour of the hysteretic prototype in respect to traditional steel anchors in masonry panels with low shear capacity. Finite Element (FE) models were also developed and calibrated applying the data from tests. Experimental and computational results are discussed in the following; the need for further theoretical work concludes the paper.

The paper describes the methodology proposed in the PERPETUATE Project (funded by the Seventh Framework Programme – Theme ENV.2009.3.2.1.1). The methodology proposed in PERPETUATE uses a displacement-based approach for the vulnerability evaluation and design of interventions. The use of safety verification in terms of displacement, rather than strength, orients to new strengthening techniques and helps in the comprehension of interaction between structural elements and unmovable artistic assets. The procedure is based on the following fundamental steps: definition of performance limit states, specific for the cultural heritage assets (considering both structural and artistic assets); evaluation of seismic hazard and soil-foundation interactions; construction knowledge (non-destructive testing, material parameters, structural identification); development of structural models for the seismic analysis of masonry structures and artistic assets and design of interventions; application and validation of the methodology to case studies. Two main scales are considered: the seismic risk assessment at territorial scale and at the scale of single historic building or artistic assets. The final aim of the project is to develop European Guidelines for evaluation and mitigation of seismic risk to cultural heritage assets.

Authors’ group has been done researches on the damage monitoring of the laminated Carbon Fiber Reinforced Plastic (CFRP) using the electrical resistance change method. The method adopts reinforcement carbon fibers as sensors, and it is called self-sensing method. Using thin CFRP laminates, delamination crack location and dimension are identified with the electrical resistance change method. However, the electrical resistance decreases when a delamination crack is made in a thick CFRP beam. The present paper experimentally investigates the effect of the dent for the measurements of electrical resistance change. Indentation tests are performed for the thick CFRP plates. The effect of the dent is calculated compared with the effect of piezoresistivity caused by the residual stress relief. As a result, the effect of the dent is larger than the effect of the residual stress relief for the thick CFRP. For the thick CFRP, dents cause the significant reduction of the electrical resistance in the thickness direction, and that causes electrical resistance decrease.

Two silane-based hybrid coatings were developed to modify the surface energy of phenolic resin impregnated paper. The coated paper samples were further pressed onto surfaces of plywood. The surface properties and water repellence of coated paper were investigated by AFM, XPS and water contact angle measurements. The water absorption of plywood with pressed paper was studied by water uptake tests. It was found that the sol-gel coatings had slightly improved the water repellence of the impregnated paper. The water absorption of plywood was also slightly decreased.

Effect of Si content of Al-Si matrix on roll cast wire inserted strip was investigated in this paper. 99.5%Al, Al-4%Si , Al-12%Si and Al-18%Si were used as matrix. Slit depth of the nozzle, superheat of melt, wire-diameter and roll speed was chosen as the casting parameters, too. Addition of the Si was useful to prevent the reaction between the matrix and the wire. A downward melt drag twin roll caster could cast the wire inserted strip of the Al-Si matrix of which Si content was ranging up to18%. Composite strip, which matrix was hyper eutectic Al-18%Si, could be cast at the speeds up to 20m/min. The gap between the wire and matrix became thin when the superheat was high. When the slit depth of the nozzle was too shallow, the wire could not be inserted in the strip. The thickness of the wire inserted strip became thinner as the roll speed became higher.

The diffusion coefficient in the metallic glass-forming systems such as Pd-Cu-Ni-P exhibits a marked deviation from the Stokes-Einstein (SE) relation in the proximity of the glass transition temperature. Such a deviation is characterized by the fractional exponent p of the modified SE expression. For the material Pd43Cu27Ni10P20, it has been reported that it takes the value p = 0.75. In this work, it is shown that the value of p is highly correlated with the ratio ED / ENB, where ED and ENB are the activation energies for diffusion coefficient D and cooperativity NB defined by the Bond Strength-Coordination Number Fluctuation (BSCNF) model. The present paper reports that for the metallic glass-forming melt Pd43Cu27Ni10P20, the fractional exponent p can be calculated accurately within the framework of the BSCNF model

A multiscale constitutive framework for Ni-base superalloys has been developed, in which an efficient unit cell is adopted to describe the γ/γ’ microstructure morphology. The framework enables the prediction of the deformation and the creep and fatigue damage accumulation in CMSX-4 for a range of temperatures and stress levels. Moreover, the material microstructural degradation due to rafting and isotropic coarsening can be simulated, and the effects of this degradation on the alloy mechanical response can be quantified. The present paper focuses on the application of the model to real gas turbine components. A high pressure turbine blade finite element model is used to demonstrate the computational efficiency of the multiscale framework. Moreover, the location of critical regions and the life time are shown to differ from the results obtained from classical models that neglect the microstructure evolution.

Thermomechanical fatigue (TMF) in superalloys is growing in importance due to the introduction of advanced cooling systems but also due to the changes in demand and competition within the power generation market; this is requiring many power plants to operate under cyclic conditions. In this paper the TMF behaviour of three different single crystal nickel-based superalloys are compared. It is demonstrated that the deformation and damage mechanisms occurring during TMF are rather different from those traditionally reported for creep or isothermal fatigue. In all cases examined, the deformation is localized within a rather small number of deformation bands. While these bands were found to consist mainly of micro-twins in some alloys, in others they might be better described as slip or shear bands. Furthermore, in some circumstances these bands are prone to recrystallization. In CMSX-4, the intersection points of twins of different orientation act as initiation sites for this process. In the SCA425 alloy - of smaller gamma' content, lower creep resistance and less great oxidation resistance - twinning is observed infrequently; however the deformation is still very localized and in the distorted gamma-gamma' microstructure, along the shear bands, recrystallization is observed. Furthermore the recrystallization is enhanced by oxidation due to the development of a gamma'-depleted zone. In CMSX-4, TCP phases precipitated during long term ageing cause a more dispersed deformation behaviour which prevents recrystallization. Our findings confirm the importance of an inhomogeneous microstructure for good TMF resistance. © (2011) Trans Tech Publications Switzerland.

Environmental degradation and unsustainable use of water resources has become an obstacle to further economic development and the well-being of the population in the Li River basin. This paper explores the concept and principles of integrated water resources management (IWRM) in relation to their applicability to the Li River basin. The assessment on its physical and socioeconomic characteristics and its current institutional systems in the Li River Basin provides an appreciation of the whole river basin. Sectoral fragmentation and the absence of coordination mechanism (or body) are identified as the institutional factors in this study that caused water related issues. In order to overcome shortfalls of the current fragmented management system, formation of Watershed Management Committee is highly recommended as the core of reforming efforts, which is expected to coordinate effective planning and implementation of equitable, efficient and sustainable use of natural resources in the basin with a view to improving the sustainability of its economic development. Several other reform recommendations are also provided and expected to be a departure point towards better water governance in the Li River basin through the implementation of IWRM. Lastly we explore to what extent the proposed recommendations would be supported by the current national policy framework.

International audience; The ACCENT Project (FP7- AAT- 2007- RTD-1) will allow the European Aero Engine manufacturers to improve their competitiveness by applying adaptive control techniques to the manufacturing of their components. For the critical rotating parts of aircraft engines, the surface integrity generated after machining is a key factor on the life cycle. In this context, one particular attention has to be carried out on tool condition. The aim of this paper is to define a monitoring approach able to detect the tool condition and machining disturbances. The main failure modes characterizing this particular Nickel base drilling and the apparition of embedded chips over the machined surface were identified. By experimental techniques, cartography of failure modes was performed. The results show that flank wear and notch are the main failure modes limiting the tool life. For some cutting conditions, the tool failure occurs after the first hole due to the important cutting forces. Some interesting combinations are made between the spindle current/accelerometers/ thrust force and flank wear, tool breakage and notch. Before these correlations, a detailed signal analysis was performed, considering different disturbing phenomena, such as chips evacuation problem. Finally, a "synopsis" for process monitoring is proposed, considering the analyzed phenomena.

In this paper, one dimensional nanorod CaCO3 adsorbents were synthesized via hydrothermal method by varying the amount of polyacrylamide (PAM). The XRD results indicated that all of the characteristic peaks of synthesized adsorbents were matched well with the aragonite CaCO3 phase. FE-SEM analysis showed one dimensional nanorod structures with diameter of 40 - 70 nm and lengths up to micrometer. TG results exhibited CaCO3 adsorbents synthesized with 0.4 and 0.6 g of polyacrylamide possessed high CO2 adsorption capacities for first carbonation/calcination cycle (0.86 and 0.79 g-CO2/g-sorbent) which were higher than the theoretical CO2 adsorption capacity (0.78 g-CO2/g-sorbent) of calcium oxide based adsorbents.

金沢大学融合研究域融合科学系, The purpose of this paper is to present a new predictive control utilizing online data and stored data of input/output of the controlled system. The conventional predictive control methods utilize the mathematical model of the control system to predict an optimal future input to control the system. The model is usually obtained by a standard system identification method from the measured input/output data. The proposed method does not require the mathematical model to predict the optimal future control input to achieve the desired output. This control strategy, called just-in-time, was originally proposed by Inoue and Yamamoto in 2004. In this paper, we proposed a simplified version of the original just-in-time predictive control method. © (2014) Trans Tech Publications, Switzerland., 研究者情報DB

This paper presents the possible deviations between “realistic” (performance-based) calculations of fire resistance of steel structures and corresponding calculations made by one of the often used simplified (prescriptive) procedures of EN 1993-1-2 i.e. the method of critical temperature (MCT). The comparison is done for a case of an assembly consisting of a steel beam and a steel girder connected to each other by a bolted fin-plate connection. For such structure the MCT method suggests that the structural fire resistance is 50 minutes. However, the realistic fire resistance calculated by an advanced performance-based procedure is evaluated to 44 minutes. Although the discrepancy between the results of both methods is not significant in the presented case, this finding implies that MCT can be on the unsafe side for some cases. More future debates and clarifications are therefore encouraged regarding the actual limits of the applicability of the simplified procedures.