High Performance Regulation at Wide Range of Speeds

This Paper presents a simplified computer program for the simulation of CSI fed 3-Phase IM drive controlled by means of vector based V/f control method using MATLAB/SIMULINK simulation software. The main features of this type of simulation program are simplicity, accuracy and efficiency in terms of computation time. This simulation program can be used to verify the system design, to study system dynamic behavior and to investigate steady state waveforms of the drive system. The feasibility, reliability of the system and the validity of the control method are proved by the simulation results. The CSI drive has so many features compared to VSI drives. In addition, symmetrical GTO, when used as switching device in the CSI, makes the drive particularly suitable for implementation at medium high voltage (4160V and up) levels and also can be useful for wide range of speed control applications(from below to above rated speed)

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine

[This corrects the article DOI: 10.1186/s13054-016-1208-6.]

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Background: Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. // Methods: We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung's disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. // Findings: We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung's disease) from 264 hospitals (89 in high-income countries, 166 in middle-income countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in low-income countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. // Interpretation: Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between low-income, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Statistical design of experiments for evaluation of Y-Zr-Ti oxides as anode materials in solid oxide fuel cells

The synthetic vanadinites (Pb(x)Ca(10-x))(VO4)6F2delta, 1 < x < 9, adopt a P6(3)/m apatite structure with 9.7590 (1) < or = a < or = 10.1179 (1) A and 7.0434 (3) < or = c < or = 7.4021 (1) A. The partitioning of calcium and lead over the AI(4f) and AII(6h) positions is nonstoichiometric with lead preferentially entering the larger AII site. High-resolution electron microscopy showed that samples annealed for 10 h at 1073 K are in disequilibrium with calcium- and lead-rich microdomains co-existing at unit-cell scales. For (Pb5Ca5)(VO4)6F2delta, sintering in excess of 2 weeks is required for the metals to order macroscopically. As annealing progresses, c/a, the partitioning coefficient kPb(AI/AII) and the AIO6 metaprism twist angle (phi) adjust cooperatively to enlarge the apatite channel, and thereby accommodate higher lead content. These results demonstrate that phi is a sensitive measure of disequilibrium and a useful device for monitoring changes in apatite topology as a function of composition

Preparation of zirconia thin films by tape casting technique as electrolyte material for solid oxide fuel cells

58-64The effect of solvents ethyl methyl ketone (MEK), toluene, xylene and ethanol on the properties of thin films of zirconia prepared by the tape casting technique is reported here. It has been found that preparation of the slurry for tape casting plays an important role in controlling the textural properties of the membranes. The rheological features of the cast tapes are satisfactorily related to the solvent ratio. The toluene + xylene solvent system has been found to provide fine casting and sintering. The physical characteristics of the green tapes like thickness, density and weight losses during sintering have also been measured. The rate of heating is determined by TGA analysis of the green tapes. The role of solvents in controlling the properties of tape cast zirconia membranes is also described.</span

Synthesis and characterization of LaCoO₃ based cathode and its chemical compatibility with CeO₂ based electrolytes for intermediate temperature solid oxide fuel cell (ITSOFC)

154-160The use of alternate cathode materials with improved performance and without any chemical reaction with adjoining electrolyte is required for a reduction in operating temperature of SOFC from 1273 K to about 1073 K (ITSOFC). Cobalt containing perovskite oxides such as LaCoO₃ tend to exhibit a higher ionic conductivity due to a greater concentration of oxygen vacancies than other perovskite oxides. The mixed ionic and electronic conducting cathode of the La₁₋xSrxCoO₃₋δ systems has shown the lowest cathodic overpotential for an SOFC air electrode. In this research work, fine powders of La₀․₇₀Sr₀․₃₀CoO₃₋δ (LSC) cathode and Ce₀․₉₀Gd₀․₁₀O₂₋δ (GDC) and Ce₀․₈₀Sm₀․₂₀O₂₋δ (SDC) are synthesized by glycine nitrate combustion synthesis and systematically characterized by XRD and particle characteristics. The electrical properties of LSC cathode and GDC and SDC electrolytes are also studied. But, the crucial requirement for applicability of LSC cathode is its chemical compatibility in conjunction with the alternate solid electrolytes, GDC and SDC without any phase formation. The XRD studies showed no reaction products when the La₀․₇₀Sr₀․₃₀CoO₃₋δ cathode is mixed and calcined with GDC and SDC electrolyte at 1573 K. Hence, the LSC cathode may be combined with CeO₂ based electrolytes in ITSOFC application

Investigation of the quasi-ternary system LaMnO3-LaCoO3-"LaCuO3" II: The series LaMn0.25-xCo0.75-xCu2xO3 and LaMn0.75-xCo0.25-xCu2xO3

This paper investigates the crystal structure, thermal expansion, and electrical conductivity of two series of perovskites (LaMn0.25-x Co0.75-x Cu-2x O3-delta and LaMn0.75-x Co0.25-x Cu-2x O3-delta with x = 0, 0.025, 0.05, 0.1, 0.15, 0.2, and 0.25) in the quasi-ternary system LaMnO3-LaCoO3-"LaCuO3". The Mn/Co ratio was found to have a stronger influence on these properties than the Cu content. In comparison to the Co-rich series (LaMn0.25-x Co0.75-x Cu-2x O3-delta), the Mn-rich series (LaMn0.75-x Co0.25-x Cu-2x O3-delta) showed a much higher Cu solubility. All compositions in this series were single-phase materials after calcination at 1100 A degrees C. The Co-rich series showed higher thermal expansion coefficients (alpha(max) = 19.6 x 10(-6) K-1) and electrical conductivity (sigma(max) = 730 S/cm at 800 A degrees C) than the Mn-rich series (alpha(max) = 10.6 x 10(-6) K-1, sigma(max) = 94 S/cm at 800 A degrees C). Irregularities in the thermal expansion curves indicated phase transitions at 150-350 A degrees C for the Mn-rich series, while partial melting occurred at 980-1000 A degrees C for the Co-rich series with x > 0.15

Chemical and physical properties of complex perovskites in the La0.8Sr0.2MnO3 - La0.8Sr0.2CuO2.4 - La0.8Sr0.2FeO3 system

Perovskites resulting from discrete changes in composition within the quasi-temary system La0.8Sr0.2MnO3-delta-La0.8Sr0.2CUO2.4+delta-La0.8Sr0.2+FeO3-delta were investigated under constant experimental conditions with the objective of obtaining an overview of the variation of the properties relevant for possible future applications. Nineteen nominal perovskite compositions within this system were systematically selected and synthesized under identical conditions by the Pechini method. The experimental data obtained on quantitative chemical analysis, powder X-ray diffraction, electrical conductivity and thermal expansion are presented collectively for the first time to facilitate comparisons. The formation and distribution of the different crystallographic phases at 950 degrees C within this quasi-ternary system are shown. The DC electrical conductivity is strongly influenced by the Cu content and increases up to 276 S cm(-1) for La0.8Sr0.2CUO2.4+delta. The thermal expansion is dominated by the Cu/Mn ratio and is almost independent of the Fe content. (C) 2007 Elsevier Masson SAS. All rights reserved