The effect of continuous care model on parents’ knowledge and controlling symptoms and recurrence in children with nephrotic syndrome

Background and aims: Nephrotic syndrome is the most common manifestation of glomerular damage in children. Due to being a chronic disease as well as the need to continuing the provision cares to reduce the recurrence of disease, this research was aimed to determine the effect of continuous care model on parents’ knowledge and controlling symptoms and recurrence in children with nephrotic syndrome. Methods: This research is an experimental study which 66 children with nephrotic syndrome qualified for inclusion in the study, were randomly classified into 2 groups: Case and control. Data were collected by a researcher-designed questionnaire, and checklist for recording blood pressure, weight, blood lipids and the presence or absence of recurrence in children in the 2 groups before and after intervention. Continuous care model was carried out on test group for 6 months. Data were analyzed by SPSS software using descriptive statistics, Chi-square, and Independent t-test and McNamara tests. Results: The proportion of disease recurrence after the intervention in both case and control groups showed no significant difference (P=0.787), but mean of systolic blood pressure in both groups after the intervention showed significant differences (P=0.011). Also, the level of parents' knowledge ratio in both groups after the intervention showed significant differences (P=0.0001). Conclusion: According to the study results, it is suggested that children care needs with nephrotic syndrome will be met by using the implementation of continuous care mode

Magnetic Forces and Vibration in Wind Power Generators: Analysis of Fractional-Slot Low-Speed PM Machines with Concentrated Windings

The PhD research work presented in this thesis deals with radial magnetics forces and vibration in low-speed fractional-slot permanent magnet (PM) machines with concentrated windings. One of the applications of such machines is a direct-drive energy conversion system for wind turbines. Due to the presence of the low spatial harmonic orders in the radial forces distribution, fractional slot machines with concentrated windings can potentially have a higher vibration level than the traditional PM machines. In order to investigate the magnetic vibration characteristics, flux density distribution is computed using finite element (FE) analysis. Then, the radial and tangential force densities are calculated using the Maxwell stress tensor. Spatial harmonic analysis of the radial force density distribution provides important information regarding the vibration behavior of the machine. The radial force distribution on the stator teeth are calculated and employed as input to a structural FE analysis. In this analysis, deformations in the stator bore due to the exciting magnetic forces are computed. Experimental work is performed on a prototype 120-slot/116-pole PM generator to validate the magnetic and structural simulations. The influence of pole and slot combinations is investigated by comparing PM machines with 120 slots and 80, 112, 116 and 118 poles. Radial forces and vibration, the cogging torque and the torque ripple characteristics of these machines are studied. The effects of the slot harmonic are investigated in the prototype machine. It is discussed how the vibration behavior is changed in the case of different slot closures. The influence of loading is studied systematically; it is discussed how the d-axis and q-axis currents change the amplitude of the lowest spatial harmonic of the radial forces, and consequently the vibration level of the prototype machine

Influence of winding layout and airgap length on radial forces in large synchronous hydrogenerators

This paper investigates the flux density and radial force spatial harmonics in large salient pole synchronous hydro-generators. Vibration due to magnetic forces are mainly caused by low order harmonics in the airgap flux density distribution. The influence of winding layout and airgap length on the lowest order radial force component are analysed. Airgap flux density and radial force density distributions of three different generators are computed using finite element calculations. The flux density components that contributes to the lowest order force component, and the source for these harmonic components, are investigated. It is found that reducing the airgap length leads to a less than proportional increase in the lowest order radial force component. A rearrangement of the winding layout is found to be an effective method for reducing the lowest order radial force component.acceptedVersion© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works

Unsupervised anomaly detection of permanent-magnet offshore wind generators through electrical and electromagnetic measurements

This paper investigates fault detection in offshore wind permanent-magnet synchronous generators (PMSGs) for demagnetization and eccentricity faults (both static and dynamic) at various severity levels. The study utilizes a high-speed PMSG model on the National Renewable Energy Laboratory (NREL) 5 MW reference offshore wind turbine at the rated wind speed to simulate healthy and faulty conditions. An unsupervised convolutional autoencoder (CAE) model, trained on simulated signals from the generator in its healthy state, serves for anomaly detection. The main aim of the paper is to evaluate the possibility of fault detection by means of high-resolution electrical and electromagnetic signals, given that the typically low-resolution standard measurements used in supervisory control and data acquisition (SCADA) systems of wind turbines often impede the early detection of incipient failures. Signals analyzed include three-phase currents, induced shaft voltage, electromagnetic torque, and magnetic flux (air gap and stray) from different directions and positions. The performance of CAE models is compared across time and frequency domains. Results show that in the time domain, stator three-phase currents effectively detect faults. In the frequency domain, stray flux measurements, positioned at the top, bottom, and sides of the outside of the stator housing, demonstrate superior performance in fault detection and sensitivity to fault severity levels. In particular, radial components of stray flux can successfully distinguish between eccentricity and demagnetization.publishedVersio

Electromagnetic analysis and electrical signature-based detection of rotor inter-turn faults in salient-pole synchronous machine

In this paper, rotor inter-turn faults in salient-pole synchronous machines are investigated using finite-element analysis. The machine under study is a 22 MVA eight-pole hydropower generator with fractional-slot windings. Simulated faulty cases include 1, 2, 5, 10, and 20 short-circuited turns (out of 58 turns) in one rotor pole. In the electromagnetic analysis, the effect of faults on airgap flux density and radial forces is studied. Furthermore, this paper investigates online detection of inter-turn faults using spectral analysis of stator voltage or current is studied. The amplitude of fault-related harmonics is investigated at various fault severities, as well as at no-load and full-load operations. This paper also discusses the effects of damper bars, an influence of parallel circuits in the stator windings, and influence of the pole pair number. In addition, a comparison between fault-related harmonics in the case of dynamic eccentricity and rotor inter-turn faults is presented.acceptedVersion© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works

Validity of neutrophil gelatinase associated lipocaline as a biomarker for diagnosis of children with acute pyelonephritis

Purpose: Novel biomarkers have been investigated for various renal disorders, including urinary tract infection (UTI). The aim of this study was to assess whether urine neutrophil gelatinase associated lipocaline (NGAL), could represent a reliable biomarker for diagnosis and treatment of children with acute pyelonephritis (APN). Materials and Methods: A total of 37 children (32 females, 5 males) with APN were included in this prospective study. Urine NGAL was measured before and 5-7 days after antibiotic treatment in the UTI group, using ELISA kit and compared with 26 (8 females, 18 males) control group children admitted for other bacterial infections. Results: Mean age of the UTI group was 39 � 28 months, compared to 43.6 � 31.5 months for the control group with no statistically significant difference. Median urine NGAL level was significantly higher in patients with APN than the other subjects 0.48 (interquartile range (IQR): 0.15-0.72) vs. 0.065 (0.01-0.24), P = .001, and decreased significantly after antibiotic treatment (P = .002). Using a cutoff of 0.20 ng/mL, sensitivity and specificity of urine NGAL were 76% and 77% for prediction of APN, respectively. The area under the ROC curve (AUC) for urine NGAL was 0.75 (CI= 0.61-0.88), suggesting urine NGAL as a relatively good predictive biomarker of APN. Conclusion: Urine NGAL is a good biomarker for diagnosis and treatment monitoring of APN in children

On Uncertainty Assessment of Fatigue Damage of Propulsion Shaft Under Ice Impact

In this paper, the importance of maintenance of marine propulsion is discussed with specific focus on the use of condition monitoring to inform maintenance schedules. The design requirements of DNV GL for shafts expected to operate in ice infested waters is adapted and a method is proposed to calculate the short-term fatigue damage during ice impacts. This method uses the Palmgren-Miner rule to calculate fatigue damage based on a transient, lumped-mass model simulation of the shaft with ice loads calculated from shaft measurements using inverse methods. Relevant sources of uncertainty in this assessment method are identified and quantified in order to express the short-term fatigue damage in a stochastic form. Sources of uncertainty include uncertainty in the calculation of ice loads, uncertainty of the transient analysis and uncertainty regarding the actual failure of the shaft as predicted by the S-N material curve and the Palmgren-Miner method. Uncertainties that influence the stress history are found to be the greatest contributor to fatigue damage uncertainty. A method is discussed that calculates the remaining useful life of the shaft as a function of short-term fatigue damage and the identified sources of uncertainty. The S.A. Agulhas is used as a case study to quantify the fatigue damage.publishedVersio