720 research outputs found
Combined Operations of SFCL and Optimal Reclosing of Circuit Breakers for Transient Stability Enhancement of Power Systems
This thesis proposes the coordinated operation of optimal reclosing of circuit breakers and superconducting fault current limiter (SFCL) for enhancing the transient stability of a multi-machine power system. Transient stability performance of the combined operation of optimal reclosing of circuit breakers and SFCL is compared with that of the combined operation of conventional reclosing of circuit breakers and SFCL. Moreover, to see the effectiveness of SFCL in improving the transient stability, its performance is compared with the static var compensator (SVC). Simulation results in Matlab/Simulink environment for permanent balanced and unbalanced faults at different points in the system indicate that the proposed combination of optimal reclosing of circuit breakers and SFCL/SVC can enhance the transient stability of the system well than the combined operation of conventional reclosing of circuit breakers and SFCL/SVC. Furthermore, the SFCL performs better than the SVC for the same operating conditions of the system
A VON LIEBIG MODEL FOR WATER AND NITROGEN CROP RESPONSE
The century-old “law of the minimum” proposed by von Liebig was tested using five independent sets of crop response data on wheat, corn, cotton, silage, and sugar beets. The rival models were polynomial functions reported in the literature as the most suitable models for interpreting those data. Overall, the von Liebig model performed very well. While the nonnested hypothesis test was inconclusive with regard to silage and sugar beets, the von Liebig model rejected the polynomial specifications for wheat, corn and cotton.Crop Production/Industries,
Influence of fluoride on the electrochemical behvior of a new synthesized Ti-10Ta-2Mo alloy for biomedical applications
The aim of the present study is to investigate the corrosion resistance of a new synthesized Ti-10Ta-2Mo in 0.9%NaCl solution containing different NaF concentrations using electrochemical techniques, including open circuit potential, potentiodynamic polarization, cyclic voltammetry and electrochemical impedance spectroscopy.The results showed that Ti-10Ta-2Mo exhibits a good corrosion resistance in 0.9% NaCl as well as in 0.9%NaCl containing fluoride and even in acidified 0.9% NaCl free of fluoride ion. Very low corrosion current densities and high impedance values were obtained, indicating the passive behavior of the alloy. An active state was observed in acidified 0.9%NaCl of pH 2 in the presence of fluoride. The results showed that Ti-10Ta-2Mo is more appropriate than some materials cited in the literature, suggesting its suitability for biomedical applications.Keywords: Ti-10Ta-2Mo; NaCl 0.9%; Fluoride; EIS ; Corrosio
Dactylifera L) on the biochemical indicators of lead poisoning in male Wistar rats
This study is conducted to examine the effect of the oral administration of pectin of dates on perturbation of the biochemical parameters induced by lead. Male rats were exposed to lead acetate at 350mg/Kg for one month, after this period, rats treated during one month with the pectin of date at 3%. Rats were sacrificed, the blood and urine are collected for the biochemical assays: glucose, total protein, phosphatase acide (PAC), alkaline phosphatase (PAL), aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, urea and uric acid. The results showed that the exposure to lead has induced a disturbance in the biochemical parameters. Thus, the treatment by the pectin of dates reduced the high concentration of these parameters. Our results show that the pectins of dates may have a corrective effect on the biochemical disturbances induced by the lead.Keywords: Phoenix Dactylifera, Pectin, Lead, Biochemical parameter
Data-driven feature identification and sparse representation of turbulent flows
Identifying coherent structures in fluid flows is of great importance for reduced order modelling and flow control. However, extracting such structures from experimental or numerical data obtained from a turbulent flow can be challenging. A number of modal decomposition algorithms have been proposed in recent years which decompose time-resolved snapshots of data into spatial modes, each associated with a single frequency and growth-rate. Most prominently among them is dynamic mode decomposition (DMD). However, DMD-like algorithms create an arbitrary number of modes. It is common practice to then choose a smaller subset of these modes, for the purpose of model reduction and analysis, based on some measure of significance. In this work, we present a method of post-processing DMD modes for extracting a small number of dynamically relevant modes. We achieve this through an iterative approach based on the graph-theoretic notion of maximal cliques to identify clusters of modes and representing each cluster with a single representative mode
Performance of Vertically Stacked Horizontal Si Nanowires Transistors: A 3D Monte Carlo / 2D Poisson Schrodinger Simulation Study
In this paper we present a simulation study of 5nm vertically stacked lateral nanowires transistor (NWTs). The study is based on calibration of drift-diffusion results against a Poisson-Schrodinger simulations for density-gradient quantum corrections, and against ensemble Monte Carlo simulations to calibrate carrier transport. As a result of these calibrated results, we have established a link between channel strain and the device performance. Additionally, we have compared the current flow in a single, double and triple vertically stacked lateral NWTs
Inheritance of Reaction of a Diallel Set of Diploid Alfalfa Clones to Two Pathogens of the Blackstem Complex
In the North Central Region, Phoma herbarum var. medicaginis Rab. And Cercospora zebrine Pass. Cause more damage to alfalfa than other components of the blackstem complex. The objectives of this investigation were: (1) to determine the ecological relationship between the two pathogens, and (2) to obtain some information regarding the genetic systems in alfalfa which condition the reaction to the two fungi. A diallel set was established from eight diploid, heterozygous clones of alfalfa. One P. herbarum and two C. zebrine isolates were used. Three leaves from each plant were excised, placed in a Syracuse watch0glass, sprayed with the inoculum, floated on a 2 percent sugar solution and incubated at 68-72 F in the dark for six days. Since it was difficult to distinguish between the types of lesions produced by each pathogen parasitizing the same tissue, the gross infection was used as a basis to determine the relationship between the two fungi. The magnitude in level of infection produced by the various treatments suggested that the relationship was not neutral, and a certain type of interaction between the two pathogens did exist. Analysis of diallel crosses indicated that dominant and recessive genes in the host plants were involved in controlling resistance to both pathogens. IN addition to dominance, epistatic gene action seemed to play a major role in controlling the reaction of the host plants to both pathogens. Is was concluded that concurrent selection for resistance to both fungi is feasible
Phenotypic, molecular and technological characterization of autochthonous lactobacilli strains isolated from cow’s milk and goat of Algerian populations
The raw milk is an important reservoir of microbial diversity can have important biotechnological applications, in particular to improve the unique characteristics of dairy products. For this effect, eight strains of autochthonus Lactobacilli have been isolated from goat and cow raw milk of the local Algerian populations (Setifian and Kabyle). The strains were then identified by phenotypic and molecular approaches by amplification and sequencing of 16S rDNA as Lb.casei (C4, C5, V2 and V5), Lb. paracasei (C6) and Lb.plantarum (C7, C8, C10). Virtually all the strains studied, from a technological point of view, produced lactic acid concentrations at or above 0.89g.100 mL<sup>-1</sup>. Most strains exhibit a high capacity and are actively producing proteolytic proteases in the stationary phase between 24 and 30 hours. The strains studied can be used in the starter cultures or co-cultures for making cheese.Keywords: Lactobacillus, identification, acidification, proteolysis
A Structured Approach to Insider Threat Monitoring for Offensive Security Teams
In many countries, government agencies resort to third parties to acquire security services of many kinds, including Red Team operations to test the effectiveness of own defenses mechanisms. Absolute trust is a key requirement, lest a potentially devastating finding be exploited by a treacherous Red Team against the same entity which commissioned the operation, or sold to its adversaries. In our endeavour as a joint private-academic initiative to address this peculiar market, we observed that a structured approach to this issue is much less common than we would have expected. In this work, we outline the process we are devising to offer customers a verified environment, but integrating it with an evidence-based proof of their correct behavior during the operation, striving to solve the “Quis custodiet ipsos custodes” struggle in an offensive setting
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