Sharif Digital Repository

This study presents a comprehensive control framework to ensure desired loading margin (LM) while minimising the corresponding control cost. The proposed framework is divided into corrective control (CC) and preventive control (PC) subproblems. The CC subproblem deals with the condition that a power system encounters voltage instability as a result of severe contingencies. This control is merely devised to restore system stability. The PC subproblem is brought up when the system operates in a stable region but its LM is insufficient. In this manner, the system-operating point is changed such that the desired LM is achieved. One of the features of the proposed methodology is to consider... 

Wide-area monitoring and control system complements the classical protection systems and overcomes their drawbacks. In such systems a dynamic view of power system, using synchronized measurements in short time intervals, smaller than 20ms, is available. This new kind of system's information provides a novel preventive control action to prevent system's large disturbances. This paper proposes a new method to prevent frequency instabilities immediately after a disturbance occurs in a system. Based on online measurements sent by phasor measurement units, a single machine equivalent model including the governors' effect is computed. An accurate frequency prediction is done based on this novel... 

Contingency screening and ranking is one of the most important issues for security assessment in the field of power system operation. The objective of contingency screening and ranking is to quickly and accurately select a short list of critical contingencies from a large list of potential contingencies and rank them according to their severity. Then suitable preventive control actions can be implemented considering contingencies that are likely to affect the power system performance. In this paper a novel approach is presented for contingency ranking based on static security assessment (SSA). This method uses weighted performance index with the application of Analytical Hierarchy Process... 

Background: Gestational Diabetes Mellitus (GDM) is a health problem that is increasing around the world. Introduction: Prevention of GDM, rather than treatment, could have several benefits in terms of both health and economic cost. Even a slight reduction in maternal glucose in non-diabetic women, particularly in women at high risk for GDM, may have significant benefits for pregnancy results and the future health of off-springs. Probiotics are a relatively new intervention, which are assessed by mothers’ metabolism, and can reduce blood sugar levels, prevent gestational diabetes and reduce the maternal and fetal complications resulting from it. The aim of this study was to review the studies... 

Trucking plays a vital role in economic development in every country, especially countries where it serves as the backbone of the economy. The fast growth of economy in Iran as a developing country has also been accompanied by an alarming situation in terms of fatalities in truck-involved crashes, among the drivers and passengers of the trucks as well as the other vehicles involved. Despite the sizable efforts to investigate the truck-involved crashes, very little is known about the safety of truck movements in developing countries, and about the single-truck crashes worldwide. Thus, this study aims to uncover significant factors associated with injury severities sustained by truck drivers... 

Different causes lead to accidental oil spills from fixed and mobile sources in the marine environment. Therefore, it is essential to have a systematic plan for mitigating oil spill consequences. In this research, a general DSS is proposed for passive and active response planning in Persian Gulf, before and after a spill. The DSS is based on NOAA's advanced oil spill model (GNOME), which is now linked with credible met-ocean datasets of CMEMS and ECMWF. The developed open-source tool converts the results of the Lagrangian oil spill model to quantitative parameters such as mean concentration and time of impact of oil. Using them, two new parameters, emergency response priority number (ERPN)... 

In this work, the potential of near-infrared (NIR) and mid-infrared (MIR) spectroscopy along with chemometrics was investigated for authentication and adulteration detection of Iranian saffron samples. First, authentication of one-hundred saffron samples was examined by principal component analysis (PCA). The results showed the NIR spectroscopy can better predict the origin of samples than the MIR. Next, partial least squares-discriminant analysis (PLS-DA) was developed to detect four common plant-derived adulterants (i.e., saffron style, calendula, safflower, and rubia). In all cases, PLS-DA classification figures of merit in terms of sensitivity, specificity, error rate and accuracy were...