bluuebunny/crossref_metadata_2025_split huggingface dataset:
Magnetic equivalent circuit model for unipolar hybrid excitation synchronous machine
Authors: Kupiec Emil , Przyborowski Włodzimierz 
Published: May 2015

AbstractLately, there has been increased interest in hybrid excitation electrical machines. Hybrid excitation is a construction that combines permanent magnet excitation with wound field excitation. Within the general classification, these machines can be classified as modified synchronous machines or inductor machines. These machines may be applied as motors and generators. The complexity of electromagnetic phenomena which occur as a result of coupling of magnetic fluxes of separate excitation systems with perpendicular magnetic axis is a motivation to formulate various mathematical models of these machines. The presented paper discusses the construction of a unipolar hybrid excitation synchronous machine. The magnetic equivalent circuit model including nonlinear magnetization curves is presented. Based on this model, it is possible to determine the multi-parameter relationships between the induced voltage and magnetomotive force in the excitation winding. Particular attention has been paid to the analysis of the impact of additional stator and rotor yokes on above relationship. Induced voltage determines the remaining operating parameters of the machine, both in the motor and generator mode of operation. The analysis of chosen correlations results in an identification of the effective control range of electromotive force of the machine.
3D field analysis in 3-phase amorphous modular transformer under increased frequency operation
Authors: Tomczuk Bronisław , Koteras Dariusz 
Published: May 2015

Abstract
The calculations results of the temperature distribution in a 3-phase transformer with modular amorphous core are presented. They were performed for two frequency values which were higher than the power system one. For the 3D field analyses the Finite Element Method (FEM) was used. The calculated temperature at the points of the core surface has been verified using an infrared camera.
Optimal sizing and cost analysis of hybrid power system for a stand-alone application in Coimbatore region: a case study
Authors: Bogaraj T. , Kanakaraj J. , Kumar K. Mohan 
Published: May 2015

Abstract
This paper presents the optimal sizing of PV/Wind/Fuel Cell/Battery Hybrid Energy System for energizing a Small Scale Industrial Application or a village domestic load of 200 kW. HOMER software is used for simulation of the complete system. The solar radiation data and wind speed data used in this paper are for the place of Coimbatore, Tamil Nadu, India which is located 11.0183° N longitude and 76.9725° E latitude. The optimized sizes of components of Hybrid Power System (HPS) are found based on Levelised Cost of Energy (LCE) and total Net Present Cost (NPC). The results are presented and compared for five different combinations of HPS components. Suggestions are also presented to choose the low cost system which produces energy at low LCE.
Elimination of Iron Based Particles in Al-Si Alloy
Authors: Bolibruchová D. , Richtárech L. 
Published: May 2015

Abstract
This paper deals with influence on segregation of iron based phases on the secondary alloy AlSi7Mg0.3 microstructure by chrome. Iron is the most common and harmful impurity in aluminum casting alloys and has long been associated with an increase of casting defects. In generally, iron is associated with the formation of Fe-rich phases. It is impossible to remove iron from melt by standard operations, but it is possible to eliminate its negative influence by addition some other elements that affect the segregation of intermetallics in less harmful type. Realization of experiments and results of analysis show new view on solubility of iron based phases during melt preparation with higher iron content and influence of chrome as iron corrector of iron based phases. By experimental work were used three different amounts of AlCr20 master alloy a three different temperature of chill mold. Our experimental work confirmed that chrome can be used as an iron corrector in Al-Si alloy, due to the change of intermetallic phases and shortening their length.
The Aging Time Effects of the Pre-expanded Polystyrene on the Patterns Mechanical Properties
Authors: Buczkowska K. , Pacyniak T. 
Published: May 2015

Abstract
The aging granulate is to activate the blowing agent during the manufacturing process to granulate models can re-expand and shape the model of well-sintered granules, smooth surface and a suitable mechanical strength. The article presents the results of studies which aim was to determine the optimum time for aging pre-foamed granules for pre-selected raw materials.
The testing samples were shaped in an autoclave, with constant parameters sintering time and temperature. Samples were made at 30 minute intervals. Models have been subjected to flexural strength and hardness.
Selected Aspects of Wear Affecting Keyed Joints and Spline Connections During Operation of Aircrafts
Authors: Gębura Andrzej , Szymczak Janusz 
Published: May 2015

Abstract
The paper deals with selected deficiencies of spline connections, such as angular or parallel misalignment (eccentricity) and excessive play. It is emphasized how important these deficiencies are for smooth operation of the entire driving units. The aim of the study is to provide a kind of a reference list with such deficiencies with visual symptoms of wear, specification of mechanical measurements for mating surfaces, mathematical description of waveforms for dynamic variability of motion in such connections and visualizations of the connection behaviour acquired with the use of the FAM-C and FDM-A. Attention is paid to hazards to flight safety when excessively worn spline connections are operated for long periods of time
Badania Procesów Tribologicznych Węzłów Łożyskowych Metodami Fam-C I Fdm-A – Model Zwiększonych Oporów Biernych
Authors: Gębura Andrzej 
Published: May 2015

Abstract
W artykule przedstawiono wybrane rezultaty zastosowania metod FAM-C (prądnica prądu przemiennego) i FDM-A (prądnica prądu stałego) do kompleksowego diagnozowania węzłów łożyskowych zespołu wirnikowego jednowałowego silnika turbinowego. Prądnice prądu przemiennego przenoszą informacje o procesach wolnozmiennych, na podstawie których można monitorować luzy promieniowe, luzy podłużne, przekoszenia wałów. Prądnice prądu stałego przenoszą informacje o procesach szybkozmiennych, na podstawie których można monitorować dynamikę poszczególnych łożysk tocznych: zmiany wartości dobroci mechanicznej, wartość oporów łącznych, współczynnik poślizgu elementów tocznych, szybkość wirowania koszyka względem czopa itp. Blisko dziesięcioletnie obserwacje diagnostyczne prowadzone na licznej próbie silników podczas ich eksploatacji umożliwiły klasyfikację procesów zużywania łożysk w postaci czterech modeli fenomenologicznych. W niniejszym artykule przedmiotem rozważań będzie model zwiększonych oporów biernych
Method of Choosing the Information Technology System Supporting Management of the Military Aircraft Operation
Authors: Barszcz Piotr , Zieja Mariusz 
Published: May 2015

Abstract
The paper presents a method of choosing the information technology system, the task of which is to support the management process of the military aircraft operation. The proposed method is based on surveys conducted among direct users of IT systems used in aviation of the Polish Armed Forces. The analysis of results of the surveys was conducted using statistical methods. The paper was completed with practical conclusions related to further usefulness of the individual information technology systems. In the future, they can be extremely useful in the process of selecting the best solutions and integration of the information technology systems
Concentration of Transforming Growth Factor-beta 1 in Chronic Periapical Lesions / Ispitivanje koncentracije transformišućeg faktora rasta beta 1 u hroničnim periapeksnim lezijama
Authors: Popović Jelena , Cvetković Tatjana , Džopalić Tanja , Mitić Aleksandar , Nikolić Marija , Barac Radomir 
Published: May 2015

Summary
Host response to antigen stimulation in chronic inflammatory periapical lesions is mainly controlled by the balance between proinflammatory and anti-inflammatory cytokines. The aim of this study was to determine the concentration of TGF-β1 in the tissue homogenates of periapical lesions and to analyse its level in relation to the symptomatology of the patients and size of the lesions. Ninety three samples of chronic periapical lesions were obtained after extraction of teeth. Samples were divided according to the clinical symptoms as symptomatic and asymptomatic, and according to the size as large and small. The concentration of TGF-β1 was analyzed using ELISA. The results showed increased production of TGF-β1 in symptomatic lesions compared to asymptomatic, but the difference was not statistically significant. Statistically significant difference in TGF-β1 concentrations was observed in large lesions compared to small (p<0,001). It seems that TGF-β1 have a modulating effect on bone tissue resorption activity under the influence of proinflammatory cytokines and can be molecular prognostic marker of periapical lesion healing.
Cigarette Smoking Has no Impact on the Effect of Radioiodine Therapy in Patients with Graves Disease / Pušenje cigareta nema uticaj na ishod radiojodne terapije kod bolesnika sa Grejvsovom bolešću
Authors: Sekulić Vladan , Rajić Milena P. , Vlajković Marina , Ilić Slobodan , Stević Miloš , Mišić Ivana , Božinović Milan 
Published: May 2015

Summary
Presently, there is very little data on the impact of nicotine and other components of tobacco smoking on the outcome of radioiodine therapy (RIT) in Graves’ disease (GD). Thus, this study was aimed to analyze a possible impact of cigarette smoking on the effect of radioiodine therapy in the patients with Graves’ disease.
The study included 31 patients (16 smokers and 15 non-smokers) with GD, aged from 22 to 73 years, who were treated with a single dose of iodine-131 sodium iodide (131I-NaI) and subjected to a 12-month follow-up, thereafter. Patients were treated with antithyroid drugs (ATDs) before RIT and described very intense stressful events occurring prior to diagnosing Graves’ hyperthyroidism. A successful response to RIT was defined as euthyroidism and subclinical or clinical hypothyroidism, while an unsuccessful response was defined as persistent hyperthyroidism.
Comparison of age (47.4±9.41 vs. 49.5±13.8 years, p=0.628) at the time of RIT, applied activity of 131I-NaI (372±78.4 vs. 363±43.7 MBq, p=0.675), and duration of ATDs therapy (3.47±3.33 vs. 4.94±5.62 years, p=0.387) between smokers and non-smokers showed no significant difference. The cumulative incidence of successful response to therapy in smokers and non-smokers was 31.2 vs. 46.7% (p<0.05), 50.0 vs. 60.0% (p>0.05), 56.2 vs. 60.0% (p>0.05), and 56.2 vs. 66.7% (p>0.05) after 3, 6, 9 and 12 months, respectively.
The results showed that cigarette smoking has no impact on the effect of radioiodine therapy after twelve-month period in patients who had experienced stressful events before the occurrence of Graves’ disease. However, patients with smoking habits achieved successful response later than non-smokers.
Upper Devonian microvertebrates from the Canning Basin, Western Australia
Authors: Roelofs Brett , Playton Ted , Barham Milo , Trinajstic Kate 
Published: May 2015

Abstract
A diverse microvertebrate fauna is described from the Virgin Hills and Napier formations, Bugle Gap Limestone Canning Basin, Western Australia. Measured sections at Horse Spring and Casey Falls (Virgin Hills Formation) and South Oscar Range (Napier Formation) comprise proximal to distal slope carbonates ranging in age from the Late Devonian Frasnian to middle Famennian. A total of 18 chondrichthyan taxa are identified based on teeth, including the first record of Thrinacodus tranquillus, Cladoides wildungensis, Protacrodus serra and Lissodus lusavorichi from the Canning Basin. A new species, Diademodus dominicus sp. nov. is also described and provides the first record of this genus outside of Laurussia. In addition, the upper range of Australolepis seddoni has been extended to Late Devonian conodont Zone 11, making it the youngest known occurrence for this species. The Virgin Hills and Napier formations microvertebrate faunas show close affinities to faunas recovered from other areas of Gondwana, including eastern Australia, Iran, Morocco and South China, which is consistent with known conodont and trilobite faunas of the same age.
In vivo toxicity of a new antifungal agent 2,4-dithiophenoxy-1-iodo-4-bromo benzene: a follow up on our in vitro study / In vivo toksičnost novoga antimikotika 2,4-ditiofenoksi-1-jodo-4-bromobenzena: proširenje in vitro istraživanja
Authors: Kılıç Süloğlu Aysun , Koçkaya Evrim , Karacaoğlu Elif , Selmanoğlu Güldeniz , Loğoğlu Elif 
Published: May 2015

Abstract
Triazole fungicide fluconazole has become the most widely used antifungal agent in the world, mainly because of its ability to penetrate well into body fluids and tissues. However, it has been reported to interact with many drugs and because of its common use, the risk of resistance to fluconazole increases. This calls for new anti-fungal drugs that would be able to replace it. In 2006, a new thialo benzene derivative - 2,4-dithiophenoxy-1-iodo-4-bromo benzene (C18H12S2IBr) - was synthesised with a carbon backbone similar to fluconazole, and, according to the early in vitro tests, much greater efficiency. Followed an in vitro test of its cytotoxicity, in which the new drug showed promising results as an alternative to fluconazole. The aim of this study was take the next step and test C18H12S2IBr toxicity in vivo. We opted for a four-week test on Wistar rats, in which the new antifungal agent was orally applied at doses two and a half and five times lower than those of fluconazole. There were no changes in daily food and water consumption, but weight gain in female rats and relative organ weights changed in the treated groups, pointing to sex-related differences in drug metabolism and effects. Fluconazole significantly increased leukocytes and lowered neutrophils whereas C18H12S2IBr did not, while other haematological changes in respect to the vehicle control were similar between the treated groups. Differences in cytochrome c in the liver and kidney suggested greater apoptotic effect of the new drug, but interpretation remains inconclusive, considering that other key indicators (biochemistry and histopathology) do not support greater toxicity. Considering that C18H12S2IBr is more active at lower concentrations and has comparable toxic effects to fluconazole in rats, this new compound shows some promise in the treatment of fungal infections. Future, more detailed animal studies are needed, that will include drug interactions and molecular toxicity pathways. If the results are promising, clinical studies should follow.
Evaluation of the social and economic burden of road traffic noise-attributed myocardial infarction in Bulgarian urban population / Procjena socijalnog i ekonomskog tereta infarkta miokarda povezanog s cestovnom bukom u bugarskog urbanog stanovništva
Authors: Dzhambov Angel M. , Dimitrova Donka D. 
Published: May 2015

Abstract
Road traffic noise is a widely studied environmental risk factor for ischaemic heart disease and myocardial infarction in particular. Given that myocardial infarction is a leading disability and mortality cause in Bulgaria and that a significant proportion of the urban population is exposed to high noise levels, quantification of the burden of disease attributable to traffic noise is essential for environmental health policy making and noise control engineering. This study aimed at estimating the burden of the myocardial infarction cases attributable to road traffic noise in the Bulgarian urban population. We used the methodology for estimating the burden of disease attributable to environmental noise outlined by the World Health Organization. Risk data were extracted from a recently published meta-analysis providing updated exposureresponse relationship between traffic noise and the risk for myocardial infarction. Based on these data we calculated the fraction of myocardial infarction cases attributable to traffic noise, loss of quality-adjusted life-years (QALYs), and the economic burden, assuming € 12,000 per QALY. About 2.9 % or 101 of all myocardial infarction cases could be attributed to road traffic noise. Fifty-five of these were fatal. Nine hundred and sixty-eight QALYs were lost to these cases. The monetary value of these QALYs was about € 11.6 million. Although the measures used in this study are crude and give only an approximation of the real burden of disease from road traffic noise, they are indicative of the important social and economic aspect of noise pollution in Bulgaria. Hopefully, these results will direct the attention of epidemiologists, environmental hygienists, and health economists to this pivotal environmental issue.
Lack of Correlation of the Serum 25(OH) Vitamin D Levels with the Glycated Hemoglobin A1c and the Lipid Profile in Type 2 Diabetes Patients on Oral Antidiabetic Drugs – Preliminary Data
Authors: Bakalov D. , Boyanov M. , Tsakova A. 
Published: May 2015

Summary
Data from different studies correlating the serum 25(OH)D levels with the metabolic and glycemic parameters in type 2 diabetes patients are still varying. The objective if this study was to describe the correlation between serum 25(OH)D levels and some metabolic parameters in Bulgarian type 2 diabetes patients on oral antidiabetic drugs. One hundred type 2 diabetes patients participated - 56 men and 44 women. The mean age and diabetes duration of the women was 59.0 and 9.8 years, of the men - 58.0 and 7.7 years respectively. Complete patient history was taken and physical examination was performed (body weight and height, waist circumference). Body composition was measured on a leg-to-leg body impedance analyzer (TBF-215, Tanita Corp., Tokyo, Japan). Serum levels of vitamin D were measured by electro-hemi-luminescent detection as 25-(ОН) D Total (ECLIA, Elecsys 2010, Roche Diagnostics, Switzerland). Glycated hemoglobin A1c was measured on a NycoCard reader (Alere™). Total, HDL-cholesterol (direct) and triglycerides were analyzed on a Cobas Integra 400+ analyzer. Correlation analysis was performed on a SPSS 13.0 for Windows platform and included 10 curves. The data were first analyzed for the group as a whole and then separately for men and women as well as in the different vitamin D tertiles. The mean serum 25-OH-vitamin D levels were 23.8 ± 12.1 nmol/l in women and 33.3 ± 20.0 nmol/l in men. We were unable to find any statistically significant correlation between serum 25(OH) vitaminand the serum lipids (cholesterol profile and triglycerides). On the contrary, there was a weak correlation with the glycated hemoglobin A1c (cubic model, R2 = 0.178, p = 0.05) and the BMI (inverse model, R2 = 0.101, p = 0.038). The sub-analyses (men versus women or according to tertiles of vitamin D) did not produce any additional information. The influence of vitamin D on the parameters of the metabolic control in type 2 diabetes is very weak on an individual level. It might be only demonstrated in large epidemiological surveys.
A Study on Fracture Resistance of Class IV Cavities Treated with Pins
Authors: Boteva E. , Peycheva K. , Karayasheva D. , Pashkouleva D. , Marinova M. 
Published: May 2015

Summary
Тhе use of pins in restoration of large cavities with esthetic resin materials appear in the dental literature after 1970 and there are less than 20 publications, focused around restorations of class IV cavities. The aim of the present study is to test the role of pins in the fracture resistance in class IV restorations with resin materials. Materials and methods: 68 matured human upper and lower sound front teeth are included in the study. The groups are upper incisors, lower incisors, canines with or without pins. All cavities are filled with the same resin material, technology and Prime bond NT. Termocycling: 30 days in 30ºС, 100% humidity, 60 days in 100% humidity 2Х12 hours at 35ºС and 40ºС and 100 dry cycles, 20 seconds each in the following order - 45ºС ± 3ºС, room temperature, 5ºС, room temperature, two series, 50 each with two days between in Cultura incubator of Viva Dent 55ºС and ice. Machine for vertical load testing ZD 10/90, load in Newtons (N), from 20 N to 1275 N, speed 0.5 mm/ min, displacement from 0.1 to 1.2 mm. Type of fractures observed: adhesive, cohesive in dentine and in resin material, mixed. Results: The highest proportion of fractures observed was in front teeth with large cavities and with pins, low loading (493-503N). Front teeth with large cavities without pins have better resistance and lower proportion of fractures (488-526N). Canines are more resistible with pins and less without. Lowest resistance is found in lower front teeth when pins are present. Conclusion: In class IV restorations when tissue loses are less than 2/3 of the incisal ridge pins can decrease the fracture resistance of the teeth.
Diagnosis of Dentin Caries – Ultraviolet Fluorescence
Authors: Uzunov Ts. , Uzunov T. , Grozdanova R. , Kosturkov D. 
Published: May 2015

Summary
The technology advance in recent years determines the need of construction of modern appliances for early diagnosis of dental caries, which are categorized by great precision, non-invasiveness, easy usage and wide availability. Such non-invasive and accurate tool for diagnostics of caries is Caries Detector (LED), Bulgarian product by “Optica Laser”. The detector emits a specific wavelength of near ultraviolet light, which causes fluorescence to porphyrins - metabolic products of the life cycle of caries-inducing bacteria. The purpose of the study is piloting a new diagnostic tool for detection and monitoring of caries excavation based on fluorescence - LED UV caries detector of company “Optica laser”. Subjected to examination by caries indicator dye and UV caries detector were sixty permanent teeth with deep dentine caries. Two methods were used to assess the dentin caries - UV fluorescence detector of “Optica Laser” and staining with caries indicator - dye (Sable ™ Seek®). It was found that among all sixty teeth, the fields, closed by margins of carious process overlap. Fifty-four of tested teeth has shown bigger field of images with staining method and six - smaller in comparison to the fluorescent method. Ultraviolet fLuorescence caries detector of “Optica Laser” company is affordable and easy applicable method for controlled excavation of dentine caries. The detector can be used in daily dental practice equally with other methods. The unit has a number of advantages - non-invasiveness, lack of interaction with tooth structures, speed, reliability, efficiency, predictability and repeatability of results.