Search results for "structural"

Robust fault-tolerant H∞ control of active suspension systems with finite-frequency constraint

2015

Abstract In this paper, the robust fault-tolerant (FT) H ∞ control problem of active suspension systems with finite-frequency constraint is investigated. A full-car model is employed in the controller design such that the heave, pitch and roll motions can be simultaneously controlled. Both the actuator faults and external disturbances are considered in the controller synthesis. As the human body is more sensitive to the vertical vibration in 4–8 Hz, robust H ∞ control with this finite-frequency constraint is designed. Other performances such as suspension deflection and actuator saturation are also considered. As some of the states such as the sprung mass pitch and roll angles are hard to m…

Non-dimensional groups for air solar collectors

2003

Abstract The radiant heat captured by a passive air solar collector during a day divides itself into three fractions, of which one is transmitted by conduction to the backside, one is collected by the convective air flow, and the last one is lost through glazing. Some calculations of heat transfer taking place in a collector in 24-h periodic regime have been done with different combinations of the values of the relevant thermo-physical variables. Calculation results were the fractions of energy transmitted to the internal room through the wall by conduction and with the air flow by convection, and lost through the glazing. The results give rise to a correlation among non-dimensional variabl…

On the impact of the heat transfer modelling approach on the prediction of EU-DEMO WCLL breeding blanket thermal performances

2020

Abstract The Water-Cooled Lithium-Lead Breeding Blanket is a key component of a fusion power plant, in charge of ensure Tritium production, shield Vacuum Vessel and magnets and remove the heat power deposited by radiation and particles arising from plasma. The last function is fulfilled by First Wall and Breeding Zone independent cooling systems. Several layouts of BZ coolant system have been investigated in the last years to identify a configuration that might guarantee EUROFER temperature below the limit (550 °C) and good thermal-hydraulic performances (i.e. water outlet temperature of 328 °C). A research activity is conducted to study and compare different modelling approaches to simulat…

Heat transfer calculation in a free convection air solar collector

1998

This paper deals with the free convective air flow developing in a vertical channel with a rectangular cross-section heated on one side. The channel geometric and physical properties are such as to simulate an air solar collector suitable for building heating. A calculation method that can be applied to the transient combined heat transfer by conduction through the wall and by convection from the wall to the air stream is presented. The conduction across the wall is computed with a one-dimensional, time-dependent finite difference scheme, with convective boundary conditions at both wall surfaces. For the free convective flow along the channel, the air flow rate and the mean convective coeff…

Mixed MHD convection and Tritium transport in fusion-relevant configurations

2005

Mixed MHD flow and Tritium transport were computed for a slender poloidal duct, representative of a DEMO HCLL blanket element. 2-D flow and temperature fields were computed in the duct's cross section under the assumption of parallel, fully developed flow, while Tritium concentration C was found by solving a fully 3-D problem with simplifying assumptions at the duct's ends. The spatial distribution of C depended on the intensity and direction of the forced flow. Significant peak factors were obtained if the net flow rate was so low that re-circulation occurred; C maxima were attained near the walls for upward flow, in the core region for downward flow.

The future of transmission electron microscopy (TEM) in biology and medicine.

2000

Innovation in services through learning in a joint venture

2011

Innovation determines a firm's competitiveness and survival and a joint venture is a fast and effective way to acquire the missing knowledge that partners require to innovate, but ‘knowing how to cooperate’ can be a determining factor in achieving the successful transfer of knowledge. Employing a sample of 81 service-sector firms and using a structural equation modeling methodology, we found a positive and direct impact between the cooperative learning process and partners' commitment to innovation.

Cooperative Spin Transition in the Two-Dimensional Coordination Polymer [Fe(4,4′-bipyridine)2(NCX)2]·4CHCl3 (X = S, Se)

2011

Two new isostructural two-dimensional (2D) coordination polymers exhibiting spin crossover (SCO) behavior of formulation [Fe(4,4'-bipy)(2)(NCX)(2)]·4CHCl(3) (4,4'-bipy = 4,4'-bipyridine; X = S [1·4CHCl(3)], Se [2·4CHCl(3)]) have been synthesized and characterized, and both undergo cooperative spin transitions (ST). For 1·4CHCl(3) the ST takes place in two steps with critical temperatures of T(c1)(down) = 143.1 K, T(c2)(down) = 91.2 K, T(c1)(up) = 150.7 K, and T(c2)(up) = 112.2 K. 2·4CHCl(3) displays half ST characterized by T(c)(down) = 161.7 K and T(c)(up) = 168.3 K. The average enthalpy and entropy variations and cooperativity parameters associated with the ST have been estimated to be ΔH…

The odd association of a C3h trisamidinium cation and tosylate anion with a series of linear oxalate-bridged trinuclear heterometallic complexes

2013

A series of six isostructural heterometallic trinuclear oxalate-bridged complexes of the formula (TDbenz)(2)(TsO)(2)[M(II)(H(2)O)(2){(μ-ox)M(III)(ox)(2)}(2)]·6H(2)O·2CH(3)OH (TDbenz = 1,3,5-tris[2-(1,3-diazolinium)]benzene; TsO = 4-methylbenzenesulfonate; ox = oxalate; M(III) = Fe, M(II) = Mn (1), Fe (2), Co (3); M(III) = Cr, M(II) = Mn (4), Fe (5), Co (6)) have been synthesized from (NH(4))(3)[M(III)(ox)(3)]·3H(2)O, the chloride salts of the divalent metal ions and the tosylate salt of 1,3,5-tris[2-(1,3-diazolinium)]benzene (trisamidinium). Whereas the crystal structures of compounds 2, 3, 4 and 5 have been investigated by single-crystal X-ray diffraction, the structures of 1 and 6 have be…

Coping and Life Satisfaction in Colombian Older Adults

2021

Background. Effective coping strategies facilitate older adults’ optimal adaptation and contribute to their well-being. Problem-focused strategies are associated with active styles and enhance well-being. This study analyzes the role of coping strategies in Colombian older adults’ subjective well-being (SWB) using structural equation modelling. Additionally, Confirmatory Factor Analyses of the Life Satisfaction Scale and Coping Strategies Questionnaires are performed. Method. A cross-sectional study is conducted with 455 Colombian older adults, ranging from 65 to 92 years old. Results. The results show that problem-focused coping has a positive effect on SWB, whereas emotion-focused coping …