Search results for "cost"
showing 10 items of 5421 documents
Lower and Upper Bounds of Manufacturing Cost in FMS
1993
Abstract The use of traditional techniques of product costing, cost control and performance evaluation in advanced manufacturing environment supplies poor results to operations management. In this paper, after a brief review of the major drawbacks of traditional machining economics, a new framework for product costing will be presented. The basis of the proposed approach lies on an analysis of the production process aimed at single out proper cost drivers for the use of the various employed manufacturing resources. As a consequence, the quota of the manufacturing cost of uncertain allocation is drastically reduced. A lower and an upper bound value of the unit production cost are also define…
Analysis of the accuracy of fiber-optic strain transducers installed by using composite smart patches
2015
The aim of this work is to investigate the accuracy of fiber-optic strain transducer related to the incomplete load transmission that can occur on composite smart patches used as base support for the installation of such transducer, commonly used for structural monitoring of concrete elements. In detail, since the dimensions of the transducer are generally very small compared to those of the structural element being monitored, attention is given not to the global reinforcement effect, which occurs when the transducer alters the entire strain field of the transversal section of the monitored element, but rather to the so-called local reinforcement effect, which is due to an incomplete load …
A Sparsity-Aware Approach for NBI Estimation and Mitigation in Large Cognitive Radio Networks
2016
Underlay cognitive networks should follow strict interference thresholds to operate in parallel with primary networks. This constraint limits their transmission power and eventually the coverage area. Therefore, in this paper, we first design a new approach for asynchronous narrow-band interference (NBI) estimation and mitigation in orthogonal frequency-division multiplexing cognitive radio networks that does not require prior knowledge of the NBI characteristics. Our proposed approach allows the primary user to exploit the sparsity of the secondary users' interference signal to recover it and cancel it based on sparse signal recovery theory. We also propose two subcarrier selection schemes…
Performance of two innovative stress sensors imbedded in mortar joints of new masonry elements
2021
Abstract Many historical cities enjoy the presence of masonry buildings with inestimable historical, artistic and cultural value. Old masonry buildings often suffer structural deficiencies, design faults and materials aging process. In recent years, many researchers focused their attention on the opportunities that structural health monitoring (SHM) can ensure for the health state of existing masonry structures, where damage can be difficult to be promptly predicted, pontentially causing abrupt collapses, with high risks for the community. This paper presents an experimental study on the effectiveness of two types of stress sensor for SHM of new masonry elements. Ceramic piezoelectric senso…
Analytical model for high-strength concrete columns with square cross-section
2008
In the present paper a mechanical model to predict the compressive response of high strength short concrete columns with square cross-section confined by transverse steel is presented. The model allows one to estimate the equivalent confinement pressures exercised by transverse steel during the loading process taking into account of the interaction of the stirrups with the inner core both in the plane of the stirrups and in the space between two successive stirrups. The lateral pressure distributions at hoop levels are obtained by using a simple model of elastic beam on elastic medium simulating the interaction between stirrups and concrete core, including yielding of steel stirrups and dam…
Improving the sustainability of transportation: environmental and functional benefits of right-turn by pass lanes at roundabouts
2015
The functional performances of conventional roundabouts (single-lane and multi-lane) and innovative roundabouts (spiral, flower, C and turbo) can be improved through right-turn bypass lanes controlled by stop, yield or free-flow signs. The article presents evaluations of the emissions of air pollutants (carbon dioxide, nitrogen oxides, particle pollution (PM10 and PM2.5)), fuel consumption and construction, management, energetic and environmental costs in roundabouts without or with bypass lanes (controlled by stop, yield or free-flow). The suggested methodology has a general character and can be applied as a multi-parametric criterion for choosing road intersections, although, in the prese…
Battery storage systems for peak load shaving applications: Part 2: Economic feasibility and sensitivity analysis
2016
This paper is the second of a two-part series, aiming to evaluate the economic feasibility of electrochemical storage systems in peak load shaving applications. The battery energy storage system (BESS) is considered to be added to a private facility, with the aim of reducing the customer electricity bill. The BESS is charged during the night, when the electricity prices are the lowest and discharged during the daily hours, when the prices are the highest, contemporary achieving a leveling of the daily usage pattern. The economical evaluations are carried out considering four different electrochemical technologies: lithium-ion (li-ion), advanced lead-acid, sodium-sulphur (NaS) and flow batte…
Concrete softening effects on the axial capacity of RC jacketed circular columns
2016
Abstract Among the different strengthening techniques to repair RC structures, reinforced concrete (RC) jacketing is one of the most commonly adopted, especially for columns. Its wide application is due to its easy application and relatively reduced cost with respect to other methods (e.g. FRP wrapping, Shape Memory Alloy active confinement). The target of RC jacketing is to increase axial, flexural capacity and ductility of weak existing members by means of two main effects: confinement action provided by the jacket and composite action between external jacket and inner concrete. Different theoretical studies have been carried out to calculate the strength enhancement due to confinement ac…
Thermo-mechanical post-buckling analysis of variable angle tow composite plate assemblies
2017
peer-reviewed The increasing use of composite materials for lightweight structural applications and the extended tailoring capabilities offered by variable stiffness laminates requires rapid and robust analysis tools that adequately describe the mechanical behaviour of such structures. In this work, a Rayleigh–Ritz solution for generally restrained multilayered stiffened variable angle tow plates in the post-buckling regime is presented. The plate model is based on first-order shear deformation theory and accounts for geometrical nonlinearity through von Kármán’s assumptions. General symmetric and unsymmetric stacking sequences are considered and Legendre orthogonal polynomials are employed…
Combining TMD and TLCD: analytical and experimental studies
2017
Abstract In these years several research efforts have been focused on developing efficient and reliable control devices for mitigating the structural response of tall and lightly damped buildings in case of strong dynamic excitations, such as wind and earthquake ones. In this context, Tuned Mass Dampers (TMDs) represent probably the most common control device due to their high control performances. On the other hand, Tuned Liquid Column Dampers (TLCDs) are increasingly becoming more popular because of some of their attractive features, cost-effectiveness among the others, even though they yield slightly less control performance compared to the classical TMDs. Aiming at combining the benefic…