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Developing attack models is the first step to understand cyberattacks in smart grids and develop countermeasures. In this article, a three-level nonlinear programming formulation is proposed for false data injection (FDI) cyberattacks that could result in multiple transmission line congestions without being detected by conventional bad data detection (BDD) algorithms. The model is then converted to a mixed integer linear programming (MILP) formulation to guarantee a global optimum exists. A detection framework based on recursive least-square estimation (RLSE) is developed that can successfully detect the stealthy FDIs. The developed model with the detection framework is validated through various case studies in IEEE 118-bus benchmark. [ABSTRACT FROM AUTHOR]

This paper proposes a novel distributed control architecture for output power regulation of doubly fed induction generator (DFIG) based wind turbines (WTs) with on-site battery energy storage systems (BESSs). The proposed distributed control architecture receives information from adjacent WTs+BESSs to control the DFIG's grid side converter (GSC) and the storage unit for output active/reactive power regulation and energy management purposes. The proposed method guarantees the equal active power sharing and energy management of WTs+BESSs in various wind speed conditions. A distributed controller is also designed to respond to the reactive power demand and share the reactive load demand between the GSC and BESS controllers based on their capacities. Furthermore, a controller is designed to account for the communication delays caused by the communication systems based on the IEEE standards. The proposed method is tested on the modified IEEE 14-bus power system with 10 WTs+BESSs. [ABSTRACT FROM AUTHOR]

Piling procedure may disturb the surrounding soil, due to the installation particularly for cast-in-place piles. It causes a reduction in the soil strength parameters and, consequently, pile capacity. To overcome shortcomings and also for improving piles’ capacity, postgrouting as a compensation method is recognized and more developed in recent years. Helical piles, those are used widely in marine and land projects, although, are driven by torque implementation, but soil disturbance is noticed, where number of the helices become up to 3 and more. In this paper, an experimental study program is performed by frustum-confined vessel (FCV) to investigate bearing capacity of model helical piles and also postgrouted cases’ performance. FCV has been used because of its linear distribution of vertical and horizontal stresses from zero at top to maximum at bottom which simulates real field stress conditions. Through experimental study, small-scale helical model piles were made of 4-mm-thick steel plate and have been used with a length of 750 mm. The shaft and helix diameters of model piles have been 32 and 89 mm, respectively. So, the helix-to-shaft ratio (wing ratio) was about 2.8. The helical model piles installed in fine-grained sand as a surrounding soil and then axial loading tests before and after grouting were performed to achieve ultimate pile capacity. Results indicated postgrouting can improve both ratios of toe and frictional soil–pile interactions including upgrading β andNtfactors. In addition, the post grouting phenomena can change the pile geometry due to treated soil bond, resulting better functioning. Therefore, it is a proper method to improve helical piles performance and compensate installation effects in capacity mobilization. [ABSTRACT FROM AUTHOR]

The effect of packaging method (air packaging; and modified atmospheres packaging including, MAP1: 5% O2+85% N2+10 % CO2 and MAP2: 70% O2+20% N2+10% CO2), storage temperature (4 and 8°C), and storage time (0 to 30 days) were studied on chemical, physical and sensory characteristics as well as extending the shelf life of pomegranate arils. Mold was detected in arils stored under air packaging after 9 days. The samples packaged with low oxygen atmosphere show no mold attack during 30 days storage. Arils kept in MAP1 and stored at 4°C maintained their texture and appearance better than those packaged under air and MAP2 packaging. The samples stored in MAP1 were firmer than those stored in air and MAP2 at the end of storage time. [ABSTRACT FROM AUTHOR]

For 100 sunflower head, maximum and minimum diameters, thickness, height of the ground, and mass of all seeds on sunflower head (SH) for five conventional varieties were measured. To examine the correlation between maximum SH diameter and minimum SH diameter, SH thickness, SH height from the ground and SH seeds mass, linear regression method was used. Also SH diameter and SH thickness of four sunflower hybrids varieties were measured. Log-normal, Weibull and Generalized extreme value (G.E.V) distribution were used in order to model SH diameter and SH thickness distributions of all varieties and hybrids; also, Kolmogorov-Smirnov methods were used for comparison of all probability density. Results indicated that value of average of dimensions, geometric and arithmetic mean diameter, head height from the ground, and mass of the seeds on each head of Dorsefid and Sirena varieties were more and less than the other varieties, respectively. For all varieties, there was linear correlation between maximum SH diameter and minimum SH diameters, SH thickness and mass of seeds; while there wasn't any correlation between SH height and maximum SH diameter. Results showed that whenever skewness and kurtosis had positive values, Log-normal and G.E.V distribution had good performance and whenever skewness and kurtosis had negative values, Weibull and G.E.V distribution had good performance based on Kolomogrov-Smirnov methods. [ABSTRACT FROM AUTHOR]