Comparing Kalman Filters and Observers for Power System Dynamic State Estimation with Model Uncertainty and Malicious Cyber Attacks

Kalman filters and observers are two main classes of dynamic state estimation (DSE) routines. Power system DSE has been implemented by various Kalman filters, such as the extended Kalman filter (EKF) and the unscented Kalman filter (UKF). In this paper, we discuss two challenges for an effective power system DSE: (a) model uncertainty and (b) potential cyber attacks. To address this, the cubature Kalman filter (CKF) and a nonlinear observer are introduced and implemented. Various Kalman filters and the observer are then tested on the 16-machine, 68-bus system given realistic scenarios under model uncertainty and different types of cyber attacks against synchrophasor measurements. It is shown that CKF and the observer are more robust to model uncertainty and cyber attacks than their counterparts. Based on the tests, a thorough qualitative comparison is also performed for Kalman filter routines and observers.Comment: arXiv admin note: text overlap with arXiv:1508.0725

Role of cytochrome P450 2B6 polymorphisms in unexpected methadone death

Methadone is a synthetic, long-acting opioid prescribed as an analgesic for chronic pain. It has a single chiral center forming two enantiomers, (R)-methadone and (S)-methadone, each having specific pharmacological actions. Concentrations of (R)- and (S)-methadone above therapeutic levels have the ability to cause serious, life-threatening, and fatal side effects. Cardiotoxicity is caused by elevated (S)-methadone levels by prolonging the QT interval of the heart’s electrical cycle. In 2014, methadone accounted for only 1% of all opioids prescribed for pain, but was responsible for 3,400 of the 14,838 individuals (~23%) who died in the United States from overdoses due to prescription opioids. West Virginia (WV) and Kentucky (KY) continue to have significant increases in overdose death rates involving prescription opioids. These overdoses could be due in part to the pharmacogenetics of an individual, encompassing the ability to influence the pharmacokinetic and pharmacodynamic properties of methadone, contributing to toxicity. The principle determinant of the large interindividual variability of methadone pharmacokinetics is metabolism, causing a discordance in the relationship between dose, plasma concentrations, and side effects. Single nucleotide polymorphisms (SNPs) within the genes of drug metabolizing enzymes, cytochrome P450 (CYP), may be important contributing factors in altering CYP activity, methadone metabolism and pharmacodynamics. (S)-Methadone is stereoselectively metabolized in the liver by CYP2B6. The purpose of this study was to determine if one or more SNPs located within the CYP2B6 gene contributes to a poor metabolizer phenotype for unexpected methadone deaths. A study cohort was obtained from the WV and KY Offices of the Chief Medical Examiner consisting of 125 Caucasians who suffered methadone-only fatal overdoses. Genotypic frequency of three intronic SNPs (rs2279344, rs4803419, and rs8192719) and five exonic SNPs (rs3211371, rs3745274, rs8192709, rs12721655, and rs35979566) were investigated. The differences between the observed genotypic frequencies were compared to the regional control group of 255 deceased Caucasian individuals. The frequencies of the exonic SNP rs3745274 and intronic SNP rs8192719 were enhanced in the methadone-only group. Higher blood methadone concentrations were observed in individuals who were genotyped homozygous for SNP rs3211371. The five exonic SNPs genotyped, and two others (rs2279343 and rs35773040), were individually expressed in COS-1 cells. The effect of these SNPs on the catalytic activity of the CYP2B6 enzyme was assessed by evaluating the luminescence generated from the metabolism of luminogenic luciferin-2B6 substrate. Additionally, inhibition studies were also conducted using clopidogrel to determine that the activity observed was from the CYP2B6 enzyme. Methadone was used to evaluate competitive inhibition with luciferin-2B6 substrate at the active site. The effect on CYP2B6 activity by introducing individual SNP variants resulted in the following decreasing order: rs2279343 \u3e rs3745274 \u3e wild type (CYP2B6*1), rs3211371 \u3e rs8192709 \u3e rs35773040, rs35979566. Relative to the wild type CYP2B6, SNPs rs8192709, rs35773040, and rs35979566 yielded 57%, 81%, and 94% decreased activity, respectively. Methadone inhibited the activity of the CYP2B6 enzyme by displacing the luciferin-2B6 substrate. Therefore, our investigations suggest that the differences in catalytic activity by CYP2B6 allelic variants rs8192709, rs35773040, and rs35979566 result in poor metabolizing phenotypes which may be contributing factors in decreased metabolism of (S)-methadone. Because CYP2B6 only plays a partial role in the metabolism of (S)-methadone, additional knowledge on the combination of SNPs on CYP2B6, together with SNPs on other methadone metabolizing CYP genes, can improve the proper therapeutic dosing for methadone, patient outcome, and the development of individualized medicine

Control Systems and Robotics Outreach to Middle-school Girls: Approach, Results, and Suggestions

We conducted a three-day outreach camp focused on control systems and robotics for 8th grade girls from economically disadvantaged families. The overall objective of the camp was motivating the young girls to consider pursuing a career in engineering and sciences. The main focus of the camp were hands-on labs using LEGO Mindstorms EV3 kit. Students learned about programming, sensors, motors and put their skills to test by creating a mobile robot that took part in three contests: car racing, line following, and parallel parking. A pre- and post-camp survey indicated that although program did not predominantly change the girls’ excitement towards careers in engineering and sciences, it increased the girls’ knowledge and excitement towards robotics and control systems. Our results indicate that short camps help kindle the interests of young girls, but are not able to sway them to take on engineering/science careers. In the latter case, we hypothesize that long-term STEM-based programs (e.g., a quarter or year-long robotics course) might be more effective.Cockrell School of Engineerin

Structural and Dielectric Properties of Substituted Stannate Compounds

The alkaline-earth stannates having the general chemical formula MSnO₃ ( M = Ca, Sr and Ba) have been projected as potential electronic ceramics such as thermally stable capacitors, humidity sensor, carbon dioxide sensor. There is no reliable technical information on the effect of substitutional doping on MSnO₃ system that appears to exist in the published literature. In view of the information gaps in the reported research, vigorous and systematic investigation has been carried out on two systems; SrSnO₃ and Mg₂SnO₄

Correlation of Some Dielectric Properties with Processing and Microstructure in Mg-Sn-O System

The alkaline-earth stannates having the general chemical formula MSn03 (M = Ca, Sr and Ba), have been projected as potential electronic ceramics (thermally stable capacitors, humidity sensor, carbon dioxide sensor, etc.). Even though magnesium is a member of the metal group to which Ca, Sr and Ba belong, no reliable technical information on the compounds in the pseudo-binary MgO-SnO₂ system appears to exist in the published literature. In view of the information gaps in the reported research, vigorous and systematic investigation has been carried out on the MgO-SnO₂ system. The MgO-SnO₂ system has been thoroughly studied with respect to synthesis, processing and characterisation - physical, microstructural and electrical. Two different synthesis routes have been adopted. These routes are solid-state and self-he atsustained. For each route two mixtures of different molar ratio viz., 2:1 and 1:1 have been used. In 2:1 molar ratio mixtures MgzSnO₄ has been formed as a single phase upon calcination of starting materials at 1200°C/24 h in both solid-state and self-heatsustained techniques with one or two impurity peaks at 1200°C/ 24 h. In 1:1 molar ratio, the reaction product consisted of a two-phase mixture of Mg₂SnO₄ and SnO₂. Evaluation of microstructure that is intimately related to the envisaged properties in the ceramics has been closely and systematically followed as a function of sintering at different temperatures of (1200- 16000°C) and soak - time (2-48 h). A thorough analysis of the as measured electrical data showed that the material possessed a very weak temperature dependence of capacitance (TCC) and dielectric constant (TCK) in the range 27-300°c over several decades of frequency domain. It was found that TCC value varied between (-200 to +195) ppm IK thus holding the promise to its usage as a thermally stable capacitor component in high-speed electronic devices. The average dielectric constant was found to be in the range 10-18, thus identifying this material as a low dielectric constant system as well

Contingency Planning in Traditional and Islamic Banks During the Crisis in Syria: Crisis Management Perspective

The Syrian crisis is one of the worst crisis in the world. It has dramatically affected many aspects of life and civilization. It imposed millions of emigration to many countries, and negatively affected the national economy including international companies operating in Syria, and also local.   It imposed on its economic sides the exit of many institutions and companies from the market, and also led to the adoption of different types of retrenchment strategies by companies that could not exit or those who wanted to stay challenged and motivated by the management of its operations and activities in an exceptional manner commensurate with the crisis continues to the present.   Before the Syrian crisis, banking industry (Traditional and Islamic) in Syria was growing rapidly and in a stable pace. The crisis situation has resulted an unexpected conditions that banks were have to deal with. This research highlights the negative effects of the crisis on Islamic and traditional banks operated in Syria, it also indicates some of the responses the banks has employed in order to mitigate or eliminate the crisis bad effects. The applied research has been modified to explore implementation of crisis management literature in Syrian banks (Traditional and Islamic) and the role of that implementation in supporting contingency planning.   The study found three main results. First, there is a positive and significant correlation between the crisis management and contingency planning. Second, the Syrian employees believe that Syrian banks has adapted crisis management practices. Finally, the study indicated that banks’ employee believe that their work conditions and job environment was negatively affected by the crisis situation