bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of the Thyristor Controlled Phase Shifting Transformer using PSO Algorithm
Authors: Suyono Hadi , Hasanah Rini Nur , Pranyata Paramita Dwi Putri 
Published: January 2019

The increase of power system demand leads to the change in voltage profile, reliability requirement and system robustness against disturbance. The voltage profile can be improved by providing a source of reactive power through the addition of new power plants, capacitor banks, or implementation of Flexible AC Transmission System (FACTS) devices such as Static VAR Compensator (SVC), Unified Power Flow Control (UPFC), Thyristor Controlled Series Capacitor (TCSC), Thyristor Controlled Phase Shifting Transformer (TCPST), and many others. Determination of optimal location and sizing of device injection is paramount to produce the best improvement of voltage profile and power losses reduction. In this paper, optimization of the combined advantages of TCPST and TCSC has been investigated using Particle Swarm Optimization (PSO) algorithm, being applied to the 30-bus system IEEE standard. The effectiveness of the placement and sizing of TCPST-TCSC combination has been compared to the implementation of capacitor banks. The result showed that the combination of TCPST-TCSC resulted in more effective improvement of system power losses condition than the implementation of capacitor banks. The power losses reduction of 46.47% and 42.03% have been obtained using of TCPST-TCSC combination and capacitor banks respectively. The TCPST-TCSC and Capacitor Bank implementations by using PSO algorithm have also been compared with the implementation of Static VAR Compensator (SVC) using Artificial Bee Colony (ABC) Algorithm. The implementation of the TCSC-TCPST compensation with PSO algorithm have gave a better result than using the capacitor bank with PSO algorithm and SVC with the ABC algorithm.
Performance analysis of hybrid photovoltaic/wind energy system using KY boost converter
Authors: Pushpavalli Murugan , Jothi Swaroopan N.M 
Published: January 2019

<span>Nowadays tremendous increase in renewable energy technologies available in abounding nature energy extracted from sun, wind etc. This Proposed topology gathered maximum power using multi input ky boost converters for hybrid energy. This hybrid topology operates mainly delivered the power from renewable energy sources solar/wind to dc bus. In the absence of any one source, wind or solar supplies power to the dc bus. Without any renewable energy sources battery deliver the power to dc bus.An inverter type module convert the power from dc bus to ac grid. In this paper effectiveness of hybrid renewable energy is simulated through MATLAB/SIMULINK</span>
A New Small-Signal AC Model and Closed Loop Control of a Three-Phase Interleaved Boost Converter
Authors: Rao H.V.Gururaja , Mudliyar Karuna , Mala R.C. 
Published: January 2019

<table width="593" border="1" cellspacing="0" cellpadding="0"><tbody><tr><td valign="top" width="387"><p>Renewable energy sources are increasingly being used today and solar energy is the most readily and abundantly available energy source. Boost converters are an integral part of any solar energy system. In order to obtain maximum possible energy from the solar system multi-phase interleaved boost converters are used. This paper presents the small-signal ac modelling and closed loop control of three-phase interleaved boost converter. State–space modelling methodology has been adopted to have linearized equivalent model of the boost converter. The interleaved three-phase boost converter is averaged over its one switching period and perturbed with small ac variations and finally linearized around its quiescent point to have a small signal ac model. Type III compensator is employed to improve the frequency response and closed loop control of three-phase boost converter. The controller design procedure is discussed in detail. The effect of right-half plane zero in non-minimum phase system and the appropriate pole-zero placements to overcome the maximum phase lag in such system is discussed. The compensated closed loop system is tested for load variations to observe the transient response.</p><p> </p></td></tr></tbody></table>
Half Cycle Discrete Transformation for Voltage Sag Improvement in an Islanded Microgrid using Dynamic Voltage Restorer
Authors: Srivatchan N.S. , Rangarajan P. 
Published: January 2019

Growing demand for clean and green power has increased penetration of renewable energy sources into microgrid. Based on the demand supply, microgrid can be operated in grid connected mode and islanded mode. Intermittent nature of renewable energy sources such as solar and wind has lead to number of control challenges in both modes of operation. Especially islanded microgrid throws power quality issues such as sag, swell, harmonics and flicker. Since medical equipments, semiconductor factory automations are very sensitive to voltage variations and therefore voltage sag in an islanded microgrid is of key significance. This paper proposes a half cycle discrete transformation (HCDT) technique for fast detection of voltage sag in an islanded microgrid and thereby provides fast control action using dynamic voltage restorer (DVR) to safe guard the voltage sensitive equipments in an islanded microgrid. The detailed analysis of simulation results has clearly demonstrated the effectiveness of proposed method detects the voltage sag in 0.04 sec and there by improves the voltage profile of islanded microgrid.
Japanese Cedar Pollen–Specific IgA in Nasal Secretions and Nasal Allergy Symptoms
Authors: Suzuki Motohiko , Yokota Makoto , Ozaki Shinya , Matsumoto Tamami , Nakamura Yoshihisa 
Published: January 2019

Objective: IgA-dependent degranulation of eosinophils and positive correlation between IgA and eosinophil cytotoxic protein levels in nasal secretions have been reported. However, the association between IgA and allergic reactions remains unclear. Therefore, we evaluated the changes in Japanese cedar–specific IgA levels and allergy symptoms after Japanese cedar pollen scattering in symptomatic and asymptomatic individuals sensitized to Japanese cedar pollen. Methods: Nasal secretion and serum samples were collected from 31 participants (21 symptomatic and 10 asymptomatic participants) in January (preseason) and March (peak season). Japanese cedar–specific IgA or IgE levels were measured using ELISA with diamond-like carbon-coated chips. Results: The ratio of Japanese cedar pollen–specific IgA to total IgA (rIgA) in the nasal secretions of symptomatic participants increased significantly in March compared with that in January ( P < .01); however, the ratio of specific IgE to total IgE (rIgE) in nasal secretions did not. rIgA in nasal secretions among asymptomatic participants also did not increase during pollen season. rIgA in nasal secretions was significantly correlated with nasal allergic symptoms (r = 0.82; P < .0001) with no significant correlation between rIgE and symptoms. Conclusions: To our knowledge, this is the first study to show an association between nasal symptoms and rIgA in nasal secretions, suggesting that rIgA is useful as an antigen-specific biomarker for allergic rhinitis or pollinosis. Furthermore, rIgA values in nasal secretions do not increase in asymptomatic participants sensitized to Japanese cedar during the pollen season.
Laryngeal Cryptococcosis: An Evolving Rare Clinical Entity
Authors: Worrall Douglas M. , Lerner David K. , Naunheim Matthew R. , Woo Peak 
Published: January 2019

Objectives: Describe the demographics and clinical manifestations of laryngeal cryptococcosis. Develop a simple approach to the diagnostic workup and treatment of localized laryngeal cryptococcal infection. Methods: A new case of laryngeal cryptococcosis encountered at our institution is presented and placed in context of the literature surrounding prior reported cases. PubMed, Google Scholar, SCOPUS, and Web of Science were queried from inception to August 2018 with the terms Larynx or Laryngeal and Cryptococcosis or Cryptococcus by two independent reviewers for English-language cases of cryptococcal infection of the larynx. Results: Twenty-nine unique cases of laryngeal cryptococcosis were identified. Median age at presentation was 65 years old. All patients presented with persistent or progressive hoarseness. Lesions were predominantly on the true vocal cords (79%), 38% associated with an adherent white exudate or leukoplakia. A minority (28%) was immunocompromised, and of the remaining immunocompetent hosts, 67% were found to be using nebulized or inhaled corticosteroids (ICS) prior to infection. Diagnosis should be suspected in patients with chronic laryngitis or mass lesions with the aforementioned risk factors. Diagnosis was made by histopathology with cryptococcal yeasts identified on methenamine silver (55%) and/or mucicarmine stains (48%). Serum cryptococcal antigen testing was unreliable (sensitivity = 39%). The mainstay of effective treatment was prolonged oral Fluconazole therapy, with two cases of laser therapy ablation of residual lesions. Improvement in voice and vocal lesions varied from weeks to months. Conclusions: Laryngeal cryptococcosis is a rare cause of persistent hoarseness, which appears to be clinically evolving and more frequently affecting immunocompetent hosts chronically using nebulized or inhaled corticosteroids. Laryngeal cryptococcal infection is readily treatable with prolonged oral antifungals once biopsy and histopathological stains confirm the diagnosis.
Contrast-enhanced spectral mammography in the evaluation of breast suspicious calcifications: diagnostic accuracy and impact on surgical management
Authors: Houben Ivo PL , Vanwetswinkel S , Kalia V , Thywissen T , Nelemans PJ , Heuts EM , Smidt ML , Meyer-Baese A , Wildberger JE , Lobbes MBI 
Published: January 2019

Background Detecting pathological breast calcifications remains challenging. Based on recent studies, contrast-enhanced spectral mammography (CESM) was shown to be superior compared to full-field digital mammography (FFDM). Purpose To evaluate the diagnostic accuracy of CESM in suspicious breast calcifications and its impact on surgical decision-making. Material and Methods All screening recalled patients with suspicious calcifications that underwent CESM in the period October 2012 until September 2015 were included. One experienced radiologist provided a BI-RADS classification for the FFDM images only. The evaluation was repeated for the CESM exam. In a simulated tumor board meeting, two breast surgeons decided on the preferred surgical treatment (breast conservation therapy [BCT] versus mastectomy) for all malignant cases. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated defining BI-RADS ≥4 as being malignant. In addition, differences in surgical decision-making were analyzed and compared using McNemar’s test. Results In total, 147 women were included in this study (mean age = 61 years; age range = 49–75 years). Pathology showed 82 benign and 65 malignant lesions, of which 33 were ductal carcinomas in situ and 32 were invasive lesions. Diagnostic performances of CESM (differences compared to FFDM in brackets) were: sensitivity 93.8% (+3%), specificity 36.6% (−2.5%), PPV 54% (0%), and NPV 88.2% (+4%). Based on low-energy images, surgeons suggested BCT in 89% of the cases. Based on the CESM exam, no statistical changes in decisions were observed (86% BCT, P = 0.453). Conclusion CESM only slightly improves the diagnostic accuracy of the evaluation of breast calcifications. It is not of added value compared to FFDM in guiding surgical decision-making.
Differentiation between solid pseudopapillary neoplasm of the pancreas and hypovascular pancreatic neuroendocrine tumors by using computed tomography
Authors: Wang Cheng , Cui Wenjing , Wang Jianhua , Chen Xiao , Tong He , Wang Zhongqiu 
Published: January 2019

Background Solid pseudopapillary neoplasm of the pancreas (SPNs) usually showed slight enhancement in contrast-enhanced computed tomography (CE-CT), which is similar to hypovascular pancreatic neuroendocrine tumors (hypo-PNETs). Purpose To show the values of CT imaging features in the differentiation between hypo-PNETs and SPNs. Material and Methods Forty-four patients with histologically confirmed SPNs and 24 patients with hypo-PNETs who underwent preoperative dynamic CE-CT were included. Two radiologists reviewed CT imaging findings and clinical features. Multivariate logistic regression analysis was performed to identify relevant features to differentiate SPNs and hypo-PNETs. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic performance. Results SPNs usually occurred in young women compared with hypo-PNETs (mean age = 34.5 years vs. 49.08 years, P < 0.01). SPNs usually showed an oval shape, “floating cloud” sign, calcification, and lower frequencies of metastases compared with hypo-PNETs ( P < 0.05 for all). The combined features (lower age, “floating cloud” sign, and calcification) showed acceptable diagnostic performance (area under the curve [AUC] = 0.865 with 100% sensitivity and 63.6% specificity) for differentiating SPNs from hypo-PNETs. Conclusion “Floating cloud” sign, lower age, and calcification have great potential in differentiating SPNs from hypo-PNETs.
Including selective metabolic components in current diagnostic criteria does not improve discriminative validity for metabolic syndrome: a risk score approach
Authors: Chang Huan-Cheng , Chen Sheng-Pyng , Yang Hao-Jan 
Published: January 2019

Objective To examine whether including additional metabolic components to the current five-marker system can improve the discriminative validity for diagnosing metabolic syndrome (MetS). Methods This longitudinal cohort study included data from subjects that had completed at least three health examinations during a 5-year period. The study outcome was the onset of MetS. Sociodemographic and biochemical variables were recorded for all subjects so that the adjusted relative risks (ARRs) could be calculated for 11 metabolic components. Risk scores for the development of MetS based on the ARR values were determined. The sums of the risk scores of different component combinations were used to conduct a receiver operating characteristic (ROC) curve analysis of MetS diagnosis. Results A total of 3368 individuals with complete data was analysed. The ARRs of the 11 metabolic components were all statistically significant. According to ROC analysis, although good discriminative validity (area under the curve [AUC] range, 0.954–0.976) could be achieved for MetS diagnosis by using either all 11 or combinations of six metabolic components (the five current components plus one extra component), the current five metabolic components used for diagnosis had the best discriminative validity (AUC = 0.977). Conclusion The current five metabolic components used for the diagnosis of MetS still represent the best combination with the highest discriminative validity.
Physiological Changes during Liver Transplantation
Authors: Kalpokas M. , Bookallil M. , Sheil A. G. R. , Rickard K. A. 
Published: January 2019

Thirteen patients who received liver transplants at the National Liver Transplant Unit between January 1986 and March 1987 were studied with extensive monitoring and frequent intraoperative biochemical and haematological profiles. Anaesthetic technique was standardised for all patients. Retrospective analysis of this data confirms that patient homeostasis is most disturbed at the time of revascularisation of the donor liver. In this series, revascularisation was associated with marked changes in all measured haemodynamic parameters (arterial blood pressure, cardiac index, heart rate, and filling pressures). There was also a significant fall in pH with revascularisation, followed by a gradual rise during the final phases of the operation. Potassium levels often rose sharply with revascularisation but then decreased during the rest of the operative period. Ionised calcium levels did not change significantly at any stage; however, all patients were given calcium intraoperatively. Coagulation profiles were often abnormal preoperatively. The transplant procedure was associated with further abnormalities in both coagulation and fibrinolysis. Patient temperatures were maintained at normal levels throughout the procedure.
Endotoxins and Anti-endotoxins (Their Relevance to the Anaesthetist and the Intensive Care Specialist)
Authors: Brock-Utne J. G. , Gaffin S. L. 
Published: January 2019

Endotoxins (lipopolysaccharides, LPS) are potent bacterial poisons always present within the intestines in considerable amounts. Several pathophysiological conditions such as hypovolaemia, hypoxia, intestinal ischaemia, burns and radiation lead to a breakdown in the barrier and depending upon the extent of the injury, endotoxins enter the systemic circulation in increasing amounts. Antibiotics do not inactivate the endotoxins which continue to exert their toxic effects leading to nausea, vomiting, diarrhoea, fever, disseminated intravascular coagulation, vascular collapse and organ failure. When nonabsorbable antibiotics are given prior to the insult, systemic endotoxaemia is prevented. Immunotherapy, using anti-lipopolysaccharide IgG, inactivates plasma endotoxins, destroys gram-negative bacteria and opsonises them and may become a major form of therapy. An outline of endotoxin and anti-lipopolysaccharide and its importance to the anaesthetist and intensive care specialist is presented.
Residual Psychomotor Effects following Reversal of Midazolam Sedation with Flumazenil
Authors: Short T. G. , Galletly D. C. 
Published: January 2019

The ability of flumazenil to reverse the effects of midazolam sedation was examined in a randomised, crossover, placebo controlled study in six male volunteers. Subjects received intravenous injections of either (a) midazolam 10 mg followed 10 minutes later by flumazenil 1.0 mg or (b) midazolam 10 mg followed after 10 minutes by flumazenil 4 mg or (c) placebo followed after 10 minutes by placebo. Post reversal drug effects were examined using a psychomotor battery (critical flicker fusion, digit symbol substitution, tapping test, ball-bearing test, number recall, reflex time) and linear analogue mood scales. It was found that a residual psychomotor deficit was present following flumazenil and that this persisted for up to 125 minutes after the 1.0 mg dose and 65 minutes following 4 mg. A small deterioration in performance was apparent after initial reversal with 1.0 mg, the peak deterioration occurring at 35 minutes.
Interfacial Pathways in Wood
Authors: Baillie Caroline , Tual Delphine , Terraillon Jean Christophe 
Published: January 2019

Wood structure and properties have been established for many years. The interaction of structure with properties has also been studied, but rarely from a materials science perspective. This paper attempts to focus on a particular aspect of composite structure, that of the interface. In engineered fibre composites the interface is the most important feature as it is the medium by which the stress is transferred from the matrix to the fibres so that they may bear the load. Much research has been focused on solving the optimisation of the interfacial stress transfer, as it is always suggested that the interface needs to be weak for high toughness and strong for high strength of the composite. More recent studies have identified the fact that it may be more advantageous to create an interface, which is not destructive in its energy absorbing capacity. Another area of weakness at the interface is the resistance to water ingress in certain environmental conditions. Biomimetics is an emerging approach to solving scientific issues by looking to nature to see what solutions are offered for the particular concerns of engineers and their products. In this case wood is the subject of study. It is assumed that wood has optimised its internal interfaces to cope with strength and toughness requirements as well as harsh environmental conditions. The internal interfaces thus need to be firstly examined and identified. This paper looks in a qualitative way at the three different interfacial crack paths which may be likened to those occurring in engineered composites: interfacial, interlaminar and intercellular (bundle/bundle interaction) and their proposed relation to energy absorption mechanisms, It also explores the influence of moisture on these fracture paths.
Detection of Local Preform Defects by Gas Flow Method and Statistical Analysis
Authors: Kim Sun K. , Opperer Jeremy G. , Daniel Isaac M. 
Published: January 2019

A method for testing the quality of fibrous preforms using gas flow is proposed. The method detects defects caused while placing the fibre preform in the mould by checking the deviations of measured pressures from the reference expected value at various locations in the mould during steady state gas flow through the enclosed preform. A statistical method is employed to classify the test preform into a normal group or any one of several groups associated with specific types of defects. To implement this method experimentally, a specially designed mould with multiple ports for gas injection and pressure measurement was used. Results obtained for various cases with and without preform defects were compared and analysed.
Glycemic Control in Children and Youth With Type 1 Diabetes Mellitus in Saudi Arabia
Authors: Al Zahrani Abdullah M , Al Shaikh Adnan 
Published: January 2019

Objective: To determine the glycemic control and cardio-metabolic complications of children and adolescents with type 1 diabetes mellitus (T1DM) attending a tertiary care diabetes clinic in Saudi Arabia. Methods: We conducted a retrospective cross-sectional study of children and adolescents with T1DM attending King Abdulaziz Medical City-Jeddah from 2010 to 2013. We assessed their glycemic control and diabetes management. Vitamin D status was compared with glycemic control and gender differences. Results: We identified 301 subjects (53.5% females); mean age was 13.9 ± 3.8 years. The mean duration of diabetes was 7.7 ± 3.7 years, body mass index (BMI) was 21.1 ± 4.5 kg/m2, and hemoglobin A1c (HbA1c) was 9.6% ± 1.9% in both genders. There were modest gender-specific differences in Saudi patients with T1DM, with males having more symptoms than females. Mean age at diagnosis of T1DM was slightly younger in males (6.01 ± 3.65 years) than in females (6.33 ± 3.45 years). Education was the most common reason for admission in males (32.9%), whereas diabetic ketoacidosis (DKA) was the most common reason in females (38.8%). Frequency of symptomatic hypoglycemic attacks was relatively higher in males (47.1%) than in females (42.9%). The majority of our patients (83%) were on intensive insulin regimen, having 4 injections or more per day. The remaining (17%) were on conventional insulin therapy. Only 26.2% had satisfactory HbA1c (⩽8%). The mean level of 25-hydroxyvitamin D was 35.15 ± 15.9 nmol/L and cholesterol was 4.75 ± 1.1 nmol/L. Vitamin D deficiency (25-hydroxyvitamin D ⩽ 37.5 nmol/L) was detected in 63.6% males and 67.7% females. No significant correlation between HbA1c and vitamin D deficiency was observed. Conclusions: Metabolic control among Saudi children with T1DM is less satisfactory compared with other countries. The high prevalence of vitamin D deficiency in this population supports the recommendation of vitamin D supplementation in T1DM subjects. Further studies in a larger cohort are needed to confirm our findings.