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The potential rotor heating in a 5 MW High Temperature Superconducting (HTS) Technology Demonstrator prototype motor is examined. Findings reveal the observation of measurable additional rotor heating with sea-state level-5 and motor speeds above 50 percent.

A concept for a nitrogen gas cooled hybrid, high temperature superconducting fault current limiter is proposed.

Background: The incidence of post-discharge nausea and vomiting (PDNV) after ambulatory anaesthesia using total intravenous anaesthesia with a risk-stratified anti-emetic approach is not well documented in the literature. In this study, we outline such an approach. The goal was to achieve an acceptably low rate of PDNV both immediately and the day after surgery.Methods: With ethics committee approval, adult patients undergoing outpatient surgery received a Propofol-based general anaesthetic plus standardised PONV-prophylaxis corresponding to their Apfel risk-score (0-4); ondansetron (risk-score 2), additional dexamethasone (risk-score 3), and additional droperidol (risk-score 4). On post-operative days one and two, patients scored PDNV and pain (numeric rating scale (NRS); 0 = none at all; 10 = worst imaginable). On post-operative day two, patients indicated the level of interference of PDNV and/or pain with their quality of life. Data are descriptive (%) or mean.Results: There were 222 patients included (age 43 years, 44% female, anaesthesia time 95 min). On the day of surgery, 69.4% of patients did not experience any nausea, 10.4% complained about severe (NRS > 6) nausea, 6.3% experienced vomiting or retching. On the first and second postoperative day, nausea was absent in 88.7% of patients and 97.3%, respectively. Quality of life was impacted (NRS ≥ 4) more by pain (32.8% of cases), than by PDNV (13.6%).Conclusion: Acceptably low rates of PDNV were achieved with the proposed standardised approach to PDNV prophylaxis. For almost 90% of patients, PDNV was not an issue the first day after surgery. Pain after discharge was a more common problem. [ABSTRACT FROM AUTHOR]

Background: Aim of this study was to identify factors associated with patients using the internet to find information about their upcoming surgery in general, and more specifically about anaesthesia. Methods: With Ethics committee approval, 1000 consecutive patients seen before elective surgery in the anaesthesia preoperative clinic of a Swiss Level 2 hospital were asked to complete a questionnaire. Primary outcome were patients using the internet to gather any medical information related to their upcoming hospital stay, secondary outcome patients using the internet to gather information regarding the upcoming anaesthesia. Multiple regression was performed to identify independent factors associated with internet use. Results: Eighty-two percent of the patients (n = 815) participated. 97% of those were ASA physical status 1 or 2; 83% (n = 676) had experience with previous anaesthetics, 86% (n = 700) reported to use the internet in general. Overall, about one-third of the participants used the internet to learn more about their medical condition, 26% regarding their upcoming surgical procedure. Only 7% (n = 55) obtained information about the anaesthetic. In multivariate analyses, factors associated with internet use were generally doing so, and planned moderate compared to minor surgery; not using the internet was associated with previous anaesthetic experience. Of those who did not use the Internet to learn about their anaesthetic, 34% indicated that they would have visited a trusted website. Conclusion: Only few patients used the internet to obtain information about their upcoming procedure and the anaesthetic part played an even smaller role. However, many patients would have appreciated guidance to find trustworthy internet sites. Trial registration: German Clinical Trials Register (DRKS00005434; date of registration: 27th December 2013); date of enrolment of first patient: 1st August 2013; study retrospectively registered. [ABSTRACT FROM AUTHOR]

When designing utility substations, it is necessary to consider all directional components of the electromagnetic reaction forces during short-circuit faults to properly account for their effects on substation equipment. IEEE 605 assumes straight long parallel conductors in its two-dimensional (2-D) force calculations while ignoring any bends and 3-D placement of conductors. CIGRE's Brochure 105 provides practical information on the mechanical effects of short-circuit currents in HV and EHV open air, conventional substations. Although these computational methods are easy to implement, they have several limitations and are sometimes too conservative. Previously published papers address such conservatism using dynamic analysis approaches that provide more accurate results when compared to experimental data. This paper provides two extensions to IEEE 605 and CIGRE 105 for calculating fault current reaction forces. A closed-form equation defining the simplified 2-D short-circuit force time history during a fault based on CIGRE 105 and a computationally inexpensive numerical 3-D force calculation technique are presented. [ABSTRACT FROM PUBLISHER]

This paper presents a new digital protection system to solve the protection challenges in future smart grids, i.e., fast protection and fault isolation in a loop-structured system with limited magnitude of fault current. The new system combines two protection algorithms, i.e., a differential protection as the primary algorithm and an overcurrent protection as the backup one. The new system uses real-time Ethernet and digital data acquisition techniques to overcome the restriction on data transmission over large grids. The current measurements at different locations are time-synchronized by GPS clocks, and then transmitted to a central computer via the Ethernet. As opposed to digital relays which often contain PMU functionality nowadays, this approach uses time stamps on the instantaneous current values. We build a prototype of the new system on a test-bed. The results from simulations and experiments have demonstrated that the protection system achieves fast and accurate protection. [ABSTRACT FROM AUTHOR]

A novel approach to power quality assessment based on real-time (RT) hardware-in-the-loop (HIL) simulation is proposed. The RT-HIL platform is being used for power quality studies of NAVY all-electric ships. The sensitivity for power quality deviations of a variable speed drive controller card was tested in the platform. The successful experiment has contributed to the conceptual design of a universal power quality test bed, which would have the function of testing the immunity of electric components and equipment and the consequent impact on ac distribution systems. Index Terms--All-electric ship, hardware-in-the-loop simulation, harmonics, power quality, voltage sags.

Objectives The aim of this research is to assess causes and circumstances of deaths in extremely low gestational age neonates (ELGANs) born in Switzerland over a 3-year period. Design Population-based, retrospective cohort study. Setting All nine level III perinatal centres (neonatal intensive care units (NICUs) and affiliated obstetrical services) in Switzerland. Patients ELGANs with a gestational age (GA) <28 weeks who died between 1 July 2012 and 30 June 2015. Results A total of 594 deaths were recorded with 280 (47%) stillbirths and 314 (53%) deaths after live birth. Of the latter, 185 (59%) occurred in the delivery room and 129 (41%) following admission to an NICU. Most liveborn infants dying in the delivery room had a GA ≤24 weeks and died following primary non-intervention. In contrast, NICU deaths occurred following unrestricted life support regardless of GA. End-of-life decision-making and redirection of care were based on medical futility and anticipated poor quality of life in 69% and 28% of patients, respectively. Most infants were extubated before death (87%). Conclusions In Switzerland, most deaths among infants born at less than 24 weeks of gestation occurred in the delivery room. In contrast, most deaths of ELGANs with a GA ≥24 weeks were observed following unrestricted provisional intensive care, end-of-life decision-making and redirection of care in the NICU regardless of the degree of immaturity. [ABSTRACT FROM AUTHOR]

Background: Midazolam is commonly used as a pre-anesthesia anxiolytic. It's elimination may not be fast enough for short procedures. In orally premedicated patients we obtained midazolam plasma concentrations at the end of surgical procedures and compared those to concentrations at anesthesia induction. Methods: The study was conducted prospectively with consent of the local ethics committee (Ethikkomission Kanton Thurgau, Switzerland) and carried out with written informed consent of each patient. Female patients aged 20 to 60 years undergoing elective procedures with general anesthesia were included, and were divided in two groups according to the planned surgical time: group S (<30 min) and group L (90-120 min), respectively. All patients received 7.5 mg Midazolam po as premedication. Blood samples were drawn at anesthesia induction, and at the end of surgery. Data were compared with t-test (independent samples; significance level p <0.05). Results: Twenty-five patients per group were included. Four patients were excluded from analysis, since midazolam was not detectable in any samples. Time of premedication to the 1st blood sample was not statistically different between groups, neither were Midazolam plasma levels at this time point (p = 0.94). None of the patients from group L (n = 24), but five patients in group S (n = 22) did have a higher plasma level of Midazolam at the end of the case compared to the beginning. Conclusions: The elimination half-life of oral Midazolam can lead to higher plasma levels at the end of a short procedure compared to those at induction of anesthesia. Trial registration: German Clinical Trials Register (Deutsches Register Klinischer Studien), DRKS00005429; date of registration 3rd January 2014 [ABSTRACT FROM AUTHOR]

This task force paper presents multi-domain tools and their interfacing issues to perform simulations that require expertise in multiple areas of physics, such as electrothermal, electromechanical, electrochemical, and electromagnetic simulations, etc. Features of single multi-domain simulation tools, which are capable of simulating more than one system such as electrical chemical, mechanical, etc., are discussed. In addition, programs that are not capable of performing multi-domain simulation independently but can be interfaced with other programs to perform multi-domain simulation are also covered. Two case studies are reported where multi-domain simulations are performed in offline and real-time environments through the interfacing of more than one simulation tool. [ABSTRACT FROM PUBLISHER]

This study addresses the timely issues of modelling, and defining selection criteria for, a solid-state fault isolation device (FID) intended for use in power electronics-based distribution systems (PEDS). This work subsequently derives the FID parameters by mapping the characteristics of a conventional medium-voltage distribution system onto that of the PEDS envisioned under a new multi-university Engineering Research Centre. When conventional circuit breakers are used in distribution systems, they have a relatively long clearing time, causing the voltage to collapse for a significant time. A semiconductor circuit breaker, however, is expected to be able to switch fast enough to keep a voltage disturbance within acceptable limits. The main focus of this study is to address the operational issues of the interaction between the power electronic converters and the solid-state FID. The utilisation of rate of current decrease (di/dt) control during turn-off in conjunction with passive clamping devices to manage the overvoltage that results from very fast circuit breaker operation is introduced. In contrast to a simple conventional RC-snubber circuit, the proposed overvoltage management avoids high leakage current, which is the undesirable drawback of RC-snubber circuits. The presented prototype is experimentally verified with low and medium-voltage test circuits. [ABSTRACT FROM AUTHOR]

This paper deals with the current state-of-the-art in interfacing issues related to real-time digital simulators employed in the simulation of power systems and power-electronic systems. This paper provides an overview of technical challenges encountered and their solutions as the real-time digital simulators evolved. Hardware-in-the-loop interfacing for controller hardware and power apparatus hardware are also presented. [ABSTRACT FROM AUTHOR]

Intravenous administration of fluids, electrolytes and glucose are the most common interventions in hospitalized pediatric patients. Parenteral fluid administration can be life-saving, however, if used incorrectly it also carries substantial risks. Perioperatively, adequate hydration, prevention of electrolyte imbalances and maintenance of normoglycemia are the main goals of parenteral fluid therapy. Conceptionally, the distinction between maintenance requirements, deficits and ongoing loss is helpful. Although the pathophysiological basis for parenteral fluid therapy was clarified in the first half of the 20th century, some aspects still remain controversial. In newborn infants, rational parenteral fluid therapy must take into account large insensible fluid losses, adaptive changes of renal function in the first days of life and the fact that neonates do not tolerate prolonged periods of fasting. In older infants the occurrence of iatrogenic hyponatremia with the use of hypotonic solutions has led to a critical reappraisal of the validity of the Holliday-Segar method for calculating maintenance fluid requirements in the postoperative period. Pragmatically, only isotonic solutions should be used in clinical situations which are known to be associated with increases in antidiuretic hormone (ADH) secretion. In this context, it is important to realize that in contrast to lactated Ringer's solution, the use of normal saline can lead to hyperchloremic acidosis in a dose-dependent fashion. Although there is no convincing evidence that colloids are better than crystalloids, there are clinical situations where the use of the more expensive colloids seems justified. It may be reasonable to choose a solution for fluid replacement which has a composition comparable to the composition of the fluid which must be replaced. Although hypertonic saline can reduce an elevated intracranial pressure, this therapy cannot be recommended as a routine procedure because there is currently no evidence that this intervention improves long-term outcome in pediatric patients with traumatic brain injury. [ABSTRACT FROM AUTHOR]

This paper presents a detailed model for simulation of a Superconducting Magnetic Energy Storage (SMES) system. SMES technology has the potential to bring real power storage characteristic to the utility transmission and distribution systems. The principle of SMES system operation is reviewed in this paper. To understand transient and dynamic performance of a SMES system, a detailed SMES system benchmark model is given with extensive simulation results. This system is demonstrated using an electromagnetic transient program—PSCAD/EMTDC. [ABSTRACT FROM AUTHOR]

Superconducting electrical machines are increasingly of interest for diverse applications such as generators, synchronous condensers and motors. These machines' dynamic behavior differs from that of conventional machines in significant ways due, to certain time constants and reactances being very different. These differences can present difficulties when conventional testing procedures are applied. A 5 MW superconducting rotor machine designed and built by American Superconductor Corporation is currently being tested in the Advanced Test Facility of the Center for Advanced Power Systems at Florida State University. A variety of test procedures are being applied to determine the machine's dynamic performance and the effectiveness of these tests when applied to a superconducting machine is being assessed. In this paper, two means of analysing test data and extracting machine parameters arc described. [ABSTRACT FROM AUTHOR]

A model for the SCFCL suitable for use in real time computer simulation is presented. The model accounts for the highly nonlinear quench behavior of BSCCO and includes the thermal aspects of the transient phenomena when the SCFCL is activated. Implemented in the RTDS real-time simulation tool the model has been validated against published BSCCO characteristics. As an example for an application in protection system studies, the effect of an SCFCL on a utility type impedance relay has been investigated using a real lime hardware-in-the-loop (RT-HIL) experiment. The test setup is described and initial results are presented. They illustrate the effect of how the relay misinterprets the dynamically changing SCFCL impedance as an apparently more distant fault location. It is expected that the new real-time SCFCL model will provide a valuable tool not only for further protection system studies but for a wide range of RT-HIL experiments of power systems. [ABSTRACT FROM AUTHOR]

Recent studies have demonstrated cyclooxygenase 2 (COX-2) overexpression in various human malignancies, especially in breast cancer, where COX-2 turned out to be a predictor of poor survival. To evaluate the relation of COX-2 and Ep-CAM overexpression and its prognostic significance, we performed a retrospective study on 212 breast cancer patients with a median follow-up time of 10.5 years. Overexpression of COX-2 in tumour tissue samples was assessed by immunohistochemistry. COX-2 overexpression was found in 48.6% of the tumour samples and was predictive for poor disease-free and overall survival. Univariate analysis revealed a strong correlation between COX-2 and Ep-CAM overexpression (P=0.009). Concurrent COX-2 and Ep-CAM overexpression was present in 21.7% of tumour specimens and had an additive negative impact on disease-free and overall survival. Determination of both tumour markers should help in guiding new therapeutic strategies in patients with invasive breast cancer. [ABSTRACT FROM AUTHOR]