Search results for " Character"

Assessment of the Usability and Accuracy of Two-Diode Models for Photovoltaic Modules

2017

Many diode-based equivalent circuits for simulating the electrical behaviour of photovoltaic (PV) cells and panels are reported in the scientific literature. Two-diode equivalent circuits, which require more complex procedures to calculate the seven model parameters, are less numerous. The model parameters are generally calculated using the data extracted from the datasheets issued by the PV panel manufactures and adopting simplifying hypotheses and numerical solving techniques. A criterion for rating both the usability and accuracy of two-diode models is proposed in this paper with the aim of supporting researchers and designers, working in the area of PV systems, to select and use a model…

Incidence of PV module rated power tolerances on PV system energy production

2016

Discussing the electrical energy production of a PV system realized by PV modules with a large range of tolerance for the rated power values is the aim of this paper. In particular, the paper shows how the incidence of tolerance can be significant, in terms of output power reduction, when the PV system works in partial shading condition. For this issue, using a tool developed for this purpose, several simulations have been run, which consider different tolerance values for the module rated power and different shading patterns for the PV array. The authors quantify the peak power values of the different system configurations, showing the importance of the choice of modules with reduced toler…

A Criterion for Rating the Usability and Accuracy of the One-Diode Models for Photovoltaic Modules

2016

In selecting a mathematical model for simulating physical behaviours, it is important to reach an acceptable compromise between analytical complexity and achievable precision. With the aim of helping researchers and designers working in the area of photovoltaic systems to make a choice among the numerous diode-based models, a criterion for rating both the usability and accuracy of one-diode models is proposed in this paper. A three-level rating scale, which considers the ease of finding the data used by the analytical procedure, the simplicity of the mathematical tools needed to perform calculations and the accuracy achieved in calculating the current and power, is used. The proposed criter…

Assessment of the Usability and Accuracy of the Simplified One-Diode Models for Photovoltaic Modules

2016

Models for photovoltaic (PV) cells and panels, based on the diode equivalent circuit, have been widely used because they are effective tools for system design. Many authors have presented simplified one-diode models whose three or four parameters are calculated using the data extracted from the datasheets issued by PV panel manufactures and adopting some simplifying hypotheses and numerical solving techniques. Sometimes it may be difficult to make a choice among so many models. To help researchers and designers working in the area of photovoltaic systems in selecting the model that is fit for purpose, a criterion for rating both the usability and accuracy of simplified one-diode models is p…

A NEW FIVE-PARAMETER MODEL FOR PHOTOVOLTAIC PANELS- DETERMINATION OF COMMERCIAL MODULES I-V CHARACTERISTICS

2010

A Saturation Model of the Synchronous Reluctance Motor and its Identification by Genetic Algorithms

2018

This paper proposes a complete saturation model of the Synchronous Reluctance Motor (Syn1231), accounting for both the self-saturation and cross-saturation effects. This model is based on an analytical relationship between the stator flux and current components, and is characterized by parameters presenting an interesting physical interpretation, differently from many other saturation model in the scientific literature. It proposes also an identification technique of such a model based on stand-still tests, without the need of locking the rotor. The proposed saturation model permits the complete description of the magnetic behaviour of the machine with 8 parameters, fewer than those require…

A Magnetic Resonance Imaging–Based Prediction Model for Prostate Biopsy Risk Stratification

2018

IMPORTANCE: Multiparametric magnetic resonance imaging (MRI) in conjunction with MRI–transrectal ultrasound (TRUS) fusion-guided biopsies have improved the detection of prostate cancer. It is unclear whether MRI itself adds additional value to multivariable prediction models based on clinical parameters. OBJECTIVE: To determine whether an MRI-based prediction model can reduce unnecessary biopsies in patients with suspected prostate cancer. DESIGN, SETTING, AND PARTICIPANTS: Patients underwent MRI, MRI-TRUS fusion-guided biopsy, and 12-core systematic biopsy in 1 session. The development cohort used to derive the prediction model consisted of 400 patients from 1 institution enrolled between …

Biosynthesis of Lipopolysaccharide-Binding Protein in Rabbit Hepatocytes

1990

Studies reported here show that the recently discovered acute-phase protein, lipopolysaccharide-binding protein (LBP), is synthesized by hepatocytes. For these studies, explanted rabbit hepatocytes were grown in the presence of 35S-methionine. Biosynthetically labelled LBP in the cells and supernatant was identified using immunoprecipitation with rat anti-rabbit LBP antibody. This antibody immunoprecipitates both the LBP polypeptide and the glycosylated protein. With a cell-free translation system a comparison of RNA from normal rabbit liver with that isolated from acute-phase rabbit liver indicated that a translatable LBP message is only found in the RNA from acute-phase liver. Studies wit…

Spontaneous Interfacial Fragmentation of Inkjet Printed Oil Droplets and Their electrical characterization

2019

This work presents the fabrication of femtoliter-scale oil droplets by inkjet printing based on a novel mechanism for the spontaneous fragmentation at the interface with an immiscible water phase and the electrical characterization of the resulting immersed “daughter” droplets. [1] In particular, picoliter-scale fluorinated oil droplets impact on surfactant laden water phase at moderately high Weber number (101), and are subjected to spreading and capillary instabilities at the water/air interface which ultimately lead to rupture in smaller sized droplets, according to reported models for macroscale droplets systems - [2] the emerging fragmentation results in “daughter” droplets having volu…

Interfacial fragmentation and electrical characterization of inkjet printed dil droplets

2019

This work presents a novel mechanism for the spontaneous fragmentation of picoliter-scale oil droplets at the interface with an immiscible water phase, and the electrical characterization of the resulting immersed “daughter” droplets by an electrical impedance chip (see Figure). [1] In particular, picoliter-scale fluorinated oil droplets are produced by inkjet printing at velocity higher than 5 m/s. Upon impact on the surfactant laden water phase at moderately high Weber number , i.e. around 10, the oil droplet is subjected to spreading and capillary instabilities at the water/air interface. These ultimately lead to its rupture in smaller sized droplets, according to the reported models for…