• Earthquakes and Structures
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• 제19권1호
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• pp.45-57
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• 2020

This paper presents the experimental application of a new method for seismic vulnerability assessment of buildings recently introduced in literature, the SMAV (Seismic Model Ambient Vibration) methodology with reference to their operational limit state. The importance of this kind of evaluation arises from the civil protection necessity that some buildings, considered strategic for seismic emergency management, should retain their functionality also after a destructive earthquake. They do not suffer such damage as to compromise the operation within a framework of assessment of the overall capacity of the urban system. To this end, for the characterization of their operational vulnerability, a Structural Operational Index (IOPS) has been considered. In particular, the dynamic environmental vibrations of the two considered strategic buildings, the fire station and the town hall building of a small town in the South of Italy, have been monitored by positioning accelerometers in well-defined points. These measurements were processed through modern Operational Modal Analysis techniques (OMA) in order to identify natural frequencies and modal shapes. Once these parameters have been determined, the structural operational efficiency index of the buildings has been determined evaluating the seismic vulnerability of the strategic structures analyzed. his study aimed to develop a model to accurately predict the acceleration of structural systems during an earthquake.

• Wind and Structures
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• 제34권1호
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• pp.101-113
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• 2022

We experimentally investigate the high-Reynolds flow around a rectangular cylinder of aspect ratio 5:1. This configuration is the object of the international BARC benchmark. Wind tunnel tests have been carried out for the flow at zero angle of attack and a Reynolds number, based on the crossflow cylinder length and on the freestream velocity, equal, to 40 000. Velocity measurements are obtained by using hot-wire anemometry along 50 different cross-flow traverses on the cylinder side and in the near wake. Differential pressure measurements are acquired on multiple streamwise sections of the model. The obtained measurements are in a good agreement with the state-of-the-art experiments. For the first time among the several contributions to the BARC benchmark, detailed flow measurements are acquired in the region near the cylinder side and in the near-wake flow. The edges and the thickness of the shear layers detaching from the upstream edges are derived from velocity measurements. Furthermore, we compute the flow frequencies characterizing the roll-up of the shear layers, the evolution of vortical structures near the cylinder side and the vortex shedding in the wake.

• Wind and Structures
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• 제4권5호
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• pp.383-398
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• 2001

The paper describes the results of the monitoring of an elevated steel water-tank with unusual shape, 85 m high and 40 m wide. The research was carried out analysing both the static and dynamic behaviour under wind actions. The instruments used (some of which were employed for the first time for this project) are described and the data processing procedures are discussed. Comparison between the experimental results and those obtained through a numerical model gives interesting information both on the structural behaviour and on the characterisation of wind actions.

• BMB Reports
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• 제33권2호
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• pp.112-119
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• 2000

Three kinds of serine protease inhibitors, members of the Bowman-Birk trypsin inhibitor, were purified from Dolichos lablab seeds and named Dolichos protease inhibitor 1, 2 and 3 (DI-1, DI-2 and DI-3), respectively. Each inhibitor showed a single band with gel mobility at around 15.9, 12.1 and 14.6 kDa on 20% SDS-PAGE under reducing conditions. To characterize inhibitory specificity, the inhibition constant (Ki) for these inhibitors was measured against several known serine proteases. All three Dolichos protease inhibitors (DI-1, DI-2 and DI-3) inhibited the activity of trypsin and plasmin, but had no effect on thrombin and kallikrein (either for human plasma kallikrein or for porcine pancreas kallikrein). DI-1 inhibited chymotrypsin most effectively (Ki = $3.6{\times}10^{-9}\;M$), while DI-2 displayed inhibitory activity for porcine pancreatic elastase (Ki = $6.2{\times}10^{-8}\;M$). Pre-treatment of the 33 mg/kg of DI-mixture (active fractions from $C_{18}$ open column chromatography that included DI-1, DI-2 and DI-3) inhibited the induction of pseudomonal elastase-induced septic hypotension and prevented an increase in bradykinin generation in pseudomonal elastase-treated guinea pig plasma. Also, the increase of kallikrein activity, by injection of pseudomonal elastase, was inhibited by the pretreatment of the DI-mixture in a guinea pig. Since the DI-mixture had no inhibitory effect on kallikrein activity when Z-Phe-Arg-MCA was used as a substrate in vitro, its inhibitory activity in the pseudomonal elastase-induced septic hypotension model might not be due to a direct inhibition of plasma kallikrein in the activation cascade of the Hageman factor and prekallikrein system. These results suggest that the Dolichos DI-mixture might be used as an inhibitor in pathogenic bacterial protease-induced septic shock.

• Advances in nano research
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• 제5권1호
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• pp.61-67
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• 2017

A semi-empirical approach to model the temperature effects on I-V characteristics of Carbon Nanotube Field Effect Transistors (CNTFETs) is proposed. The model includes two thermal parameters describing CNTFET behaviour in terms of saturation drain current and threshold voltage, whose values are extracted from the simulated and trans-characteristics of the device in different temperature conditions. Our results are compared with those of a numerical model online available, obtaining I-V characteristics comparable but with a lower CPU calculation time.

• Journal of Computing Science and Engineering
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• 제3권4호
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• pp.238-259
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• 2009

In this paper we discuss personal data management with mobile devices, an activity requiring the composition of services offered by standard suites of applications. We propose a data model and an interface model that allows users to define activities, tasks and services, to navigate among them according to the evolution of the personal situation as perceived and interpreted by the users themselves. The interface model acts as a lens exploring the situation, zooming into the details, covering different areas of the personal data, supporting the user in the role of a composer of personal services.

• Wind and Structures
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• 제8권6호
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• pp.407-426
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• 2005

A hybrid RANS/LES approach, based on the Limited Numerical Scales concept, is applied to the numerical simulation of the flow around a square cylinder. The key feature of this approach is a blending between two eddy-viscosities, one given by the $k-{\varepsilon}$ RANS model and the other by the Smagorinsky LES closure. A mixed finite-element/finite-volume formulation is used for the numerical discretization on unstructured grids. The results obtained with the hybrid approach are compared with those given by RANS and LES simulations for three different grid resolutions; comparisons with experimental data and numerical results in the literature are also provided. It is shown that, if the grid resolution is adequate for LES, the hybrid model recovers the LES accuracy. For coarser grid resolutions, the blending criterion appears to be effective to improve the accuracy of the results with respect to both LES and RANS simulations.

• 한국자동차공학회논문집
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• 제6권3호
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• pp.97-105
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• 1998

High pressure injection is recently used to reduce the emissions and increase the power of DI diesel engine. This high pressure injection makes the spray strike the cylinder wall. This spray/wall impingement is known to affect the emission and performance of DI diesel engine such that it is very important to know the spray/wall impingement process. In this study, multidimensional computer program KIVA-II was used to clarify the effect of spray wall impingement by different injection spray angle with the spray/wall impingement model consiedering rebound and slide motion and also the improved submodel for liquid breakup, drop distortion model.

• 한국자동차공학회논문집
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• 제10권5호
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• pp.35-44
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• 2002

Engine cycle simulation using a two-zone model was performed to investigate the effect of the engine parameters on NO and soot emissions in a DI diesel engine. The present model was validated against measurements in terms of cylinder pressure, BMEP, NO emission data with a 2902cc turbocharger/intercooler DI diesel engine. Calculations were made for a wide range of the engine parameters, such as injection timing, ignition delay, Intake air pressure, inlet air temperature, compression ratio, EGR. This parametric study indicated that NO and soot emissions were effectively decreased by increasing intake air pressure, decreasing inlet air temperature and increasing compression ratio. By retarding injection timing, increasing ignition delay and applying EGR. NO emission was effectively reduced, but the soot emission was increased.

• Steel and Composite Structures
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• 제1권4호
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• pp.441-458
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• 2001

We analyzed the experimental and theoretical behavior of a particular type of steel joint designed to connect beam to beam and able to transfer both shear forces and bending moments. This joint is characterized by the use of steel plates and bolts enclosed in the width of the beams. The experimental investigation was carried out characterizing the constituent materials and testing in flexure beams constituted by two portions of beams connected in the middle with the joint proposed. Connections having different characteristics in terms of thickness of plates, number and type of bolts were utilized. Flexure tests allow one to determine the loaddeflection curves of the beam tested and the moment-rotation diagrams of the connections, highlighting the strength and the strain capacity of the joints. The proposed analytical model allows one to determine the moment-rotation relationship of the connections, pointing out the influence of the principal geometrical and mechanic characteristics of single constituents on the full properties of the joint.