24 research outputs found

    Effect of pot size, planting date and genotype on minituber production of Marfona potato cultivar

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    This study was carried out to evaluate the effects of pot size, planting date and type of genotype on mini-tuber production of Marfona potato cultivar (Solanum tuberosum L.) in greenhouse conditions.Four genotypes (M-129, M-128P, M-127P and M-124P) originated from virus free sprouts and a genotype of the same cultivar (Marfona) originated from apical meristem, in 3 sizes of pot and 3 planting datewere investigated. The results showed that using larger pots of 3-liter has no advantage and pots smaller than 2-liter is not suitable for mini-tuber production. Also, time of Nov 18 was the best of datefor planting of potato in studied conditions and delay in date of planting reduced the mini-tuber production. The reduction in number of mini-tubers and growing period was greater for the genotype M-129 compared with the other potato genotypes. Furthermore, higher numbers of mini-tubers were produced by the M-127P and M-124P genotypes and M-127P had the highest total weight of mini-tubers.However the number of mini-tubers per plant was higher for genotypes originated from meristem culture than genotypes obtained from sprouts. It seems that genotypes originated from potato sprouts are not as efficient as the apical meristem ones. On the other hand, later genotype showed more homogenous in growth rate and phenotype

    Parameter induction in continuous univariate distributions: Well-established G families

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    A Two-Loop Hybrid Method for Optimal Placement and Scheduling of Switched Capacitors in Distribution Networks

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    This paper presents a method to find the optimal size and place of the switched capacitors using a hybrid optimization algorithm. The objective function includes the active and reactive power of power plants, the capital and maintenance costs of capacitor banks, and the cost of active and reactive power losses in distribution lines and transformers. The impact of the load model on the optimal sizing and placement of switched capacitors is studied using three different scenarios: In the first scenario, all loads are voltage-dependent; in the second scenario, only a portion of loads are voltage-dependent; in the third scenario, all loads are voltage-independent. The proposed hybrid algorithm incorporates an outer and two inner optimization layers. The outer layer is executed by a genetic algorithm (GA), while the inner layer is performed by a GA, an exchange market algorithm (EMA), or a particle swarm optimization (PSO). The performance of GA-GA, GA-EMA, and GA-PSO hybrid schemes are compared on an IEEE 33-bus test system. Moreover, IEEE 33-bus and 69-bus networks are used to verify the effectiveness of proposed hybrid scheme against the gravitational search algorithm (GSA), a combination of PSO and GSA (PSOGSA), cuckoo search algorithm (CSA), teaching learning-based optimization (TLBO), and flower pollination algorithm (FPA). The results highlight the advantage of the proposed hybrid optimization scheme over the other optimization algorithms

    Atorvastatin and prevention of contrast induced nephropathy following coronary angiography

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    Background: Contrast induced nephropathy (CIN) is one of the most common complications after radiographic procedures using intravascular radiocontrast media. The aim of the current study was to assess the effect of atorvastatin on prevention of CIN in patients undergoing coronary angiography. Materials and Methods: In a clinical trial study, 200 patients referred for angiography were randomly divided into two groups of using 80 mg atorvastatin and placebo before the procedure. Furthermore, 100 patients who were under chronic treatment of statins were included as the third group. Serum creatinine (Scr) levels before and after the procedure were evaluated and incidence of CIN (post-procedural Scr of >0.5 mg/dl or >25 from baseline) was assessed. Results: Mean age of the participants was 60.06 ± 0.69 years and 276 (92) were male. There were no significant differences between group with respect to age and gender. In pre-operation atorvastatin, placebo and long term statin groups, the incidence of CIN was 1, 2 and 1, and mean changes of Glomerular filtration rate (GFR) was 3.68 ± 1.32, �0.77 ± 1.21 and 1.37 ± 0.86; and mean changes of creatinine (Cr) was �0.05 ± 0.02, 0.02 ± 0.02 and �0.01 ± 0.01 respectively. respectively (P = 0.776, 0.026 and 0.041 respectively). In pre-operation atorvastatin group, Cr decreased, and GFR increased significantly (P = 0.019 and 0.007 respectively). Conclusion: pre-operation short term high dose atorvastatin use was associated with a significant decrease in serum Cr level and increase in GFR after angiography. © 2015, Isfahan University of Medical Sciences(IUMS). All rights reserved

    DC MicroGrids

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    International audienceThis chapter introduces concepts of DC MicroGrids exposing their elements, features, modeling, control, and applications. Renewable energy sources, energy storage systems, and loads are the basics components of a DC MicroGrid. These components can be better integrated thanks to their DC feature, resulting in simpler power converter topologies, as well as the control strategy required for this application. A DC MicroGrid is developed as a realistic average model where the dynamics of the system are expressed in differential equations, including the nonlinearities of the model. A nonlinear distributed control strategy is developed for the DC MicroGrid, assuring the stability of the DC bus to guarantee the proper operation of each component of the MicroGrid. The energy storage systems are separated according to their timescale operation, where a faster one (supercapacitor) controls voltage variations on the DC bus, and a slower one (battery) provides the power flow balance. The comparison with classical linear controllers is carried out to highlight the better performance of the nonlinear approach
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