scholarly journals The influence of the deforming regime on the losses of power and energy in the electrical transformers on board the cruise ships

2021 ◽  
Vol XXIV (1) ◽  
pp. 157-166
Author(s):  
PANA L.
Keyword(s):  
Optimal Operation ◽  
Power Transformers ◽  
Variable Speed Drives ◽  
Frequency Converters ◽  
Naval Power ◽  
Cruise Ships ◽  
Electrical Transformers ◽  
Power And Energy ◽  
The Impact

Power transformers are the basic components of a naval power system at the same time as the equipment with the most significant losses. The deforming regime is introduced by the power electronics in the case of ships of static frequency converters, cycloconverters or syncroconverters (variable speed drives) for the control of propulsion motors, etc. The central theme of this paper is the impact of the deforming regime on power and energy losses in the case of electrical transformers on board cruise ships. For this purpose, the analytical model regarding the determination of losses in transformers when operating in deforming regime is presented. In addition to the winding losses, the magnetic and dielectric circuit also includes additional losses due to the deforming regime. At the same time, an analysis was performed regarding the optimal operation management of the power transformers affected by the deforming regime.

scholarly journals Performance Improvement of Pumps Fed by the Variable Speed Drives

2013 ◽  
Vol 4 (1) ◽  
pp. 45-51 ◽  
Author(s):  
Valery Vodovozov ◽  
Ilja Bakman
Keyword(s):  
Performance Improvement ◽  
Test Bench ◽  
Pump Efficiency ◽  
Variable Speed ◽  
Variable Speed Drives ◽  
Drive Control ◽  
Traditional Approaches ◽  
The Impact

Abstract Speed inaccuracy decreases the pump efficiency, reliability, and energy saving. This research is devoted to the determination of the ways of accurate speed control of the pump drives operated under changeable loads. The impact of speed inaccuracy on the pump performance is studied. Based on the analysis of methods for the static accuracy improvement, the drawbacks of the traditional approaches have been shown with reference to the pumping applications. A new methodology of the slip compensation has been proposed for implementation to improve the scalar drive performance. It notably decreases the speed inaccuracy of the open-ended pumping applications. The enhanced quality of the drive control at different loading conditions has been shown on a laboratory test bench. Also, for the multi-pump systems this approach results in an additional benefit from the viewpoint of the operation around the best operation point providing a safe pump control both to exclude the pump damage and to improve the process quality.

Consideration of Geopolitical Challenges within the Analysis of Geoenvironmental Risks for Oil and Gas Development of the Russian Arctic

2019 ◽  
Vol 16 (6) ◽  
pp. 50-59
Author(s):  
O. P. Trubitsina ◽  
V. N. Bashkin
Keyword(s):  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Optimal Operation ◽  
The Arctic ◽  
Stage Model ◽  
Oil And Gas Development ◽  
Gas Industry ◽  
The Impact ◽  
Further Development ◽  
Geopolitical Risks

The article is devoted to the consideration of geopolitical challenges for the analysis of geoenvironmental risks (GERs) in the hydrocarbon development of the Arctic territory. Geopolitical risks (GPRs), like GERs, can be transformed into opposite external environment factors of oil and gas industry facilities in the form of additional opportunities or threats, which the authors identify in detail for each type of risk. This is necessary for further development of methodological base of expert methods for GER management in the context of the implementational proposed two-stage model of the GER analysis taking to account GPR for the improvement of effectiveness making decisions to ensure optimal operation of the facility oil and gas industry and minimize the impact on the environment in the geopolitical conditions of the Arctic.The authors declare no conflict of interest

Assessment of sensitivity of the efficiency of regional tax spending towards investment attractiveness of the types of economic activity carried out by the residents of advanced development territory

2020 ◽  
pp. 98-110
Author(s):  
Evgeniya Mikhailovna Popova ◽  
Guzel Mukhtarovna Guseinova ◽  
Sergei Borisovich Milov
Keyword(s):  
Economic Activity ◽  
Socioeconomic Development ◽  
Federal District ◽  
Tax Incentives ◽  
Capital Investments ◽  
The Subject ◽  
Investment Process ◽  
The Impact ◽  
Advanced Development

The deficit of subnational budgets and deceleration capital investments in multiple Russian regions increase the relevance of research aimed at improvement of tax incentivizing practice of the regional investment process. The studies focused on determination of the impact of socioeconomic and institutional factors upon the efficiency of investment tax expenses obtained wide circulation within the foreign scientific literature. The subject of this article is the assessment of sensitivity of the efficiency of regional tax expanses towards investment attractiveness of the types of economic activity carried out by the residents of territories of advanced socioeconomic development, created in the subjects of Far Easter Federal District. The scientific novelty and practical values of this research consists in substantiation of the reasonableness of assessment of investment attractiveness of the types of economic activity that are stimulated by tax incentives. Methodology for assessing investment attractiveness is proposed and tested. The conclusion is made that in case of low investment attractiveness of the type of economic activity, which was planned to support by tax incentives, it is required to conduct and additional analysis to avoid unjustified tax expanses.

Method development for the determination of textural properties of sugar beet roots

2019 ◽  
pp. 392-400 ◽  
Author(s):  
Gunnar Kleuker ◽  
Christa M. Hoffmann
Keyword(s):  
Sugar Beet ◽  
Compression Test ◽  
Storage Period ◽  
Textural Properties ◽  
Small Sample ◽  
Root Tip ◽  
Flexural Test ◽  
Sample Distribution ◽  
The Impact

The harvest of sugar beet leads to root tip breakage and surface damage through mechanical impacts, which increase storage losses. For the determination of textural properties of sugar beet roots with a texture analyzer a reliable method description is missing. This study aimed to evaluate the impact of washing, soil tare, storage period from washing until measurement, sample distribution and number of roots on puncture and compression measurements. For this purpose, in 2017 comprehensive tests were conducted with sugar beet roots grown in a greenhouse. In a second step these tests were carried out with different Beta varieties from a field trial, and in addition, a flexural test was included. Results show that the storage period after washing and the sample distribution had an influence on the puncture and compression strength. It is suggested to wash the roots by hand before the measurement and to determine the strength no later than 48 h after washing. For reliable and comparable results a radial distribution of measurement points around the widest circumference of the root is recommended for the puncture test. The sample position of the compression test had an influence on the compressive strength and therefore, needs to be clearly defined. For the puncture and the compression test it was possible to achieve stable results with a small sample size, but with increasing heterogeneity of the plant stand a higher number of roots is required. The flexural test showed a high variability and is, therefore, not recommended for the analysis of sugar beet textural properties.

Development and Validation of an LC-MS/MS Method for Simultaneous Determination of Canagliflozin and Metformin HCl in Rat Plasma and its Application

2020 ◽  
Vol 16 (6) ◽  
pp. 752-762
Author(s):  
Vivek Nalawade ◽  
Vaibhav A. Dixit ◽  
Amisha Vora ◽  
Himashu Zade
Keyword(s):  
Internal Standard ◽  
Rat Plasma ◽  
Precipitation Method ◽  
Herbal Extracts ◽  
One Step ◽  
Precision And Accuracy ◽  
Development And Validation ◽  
The Impact ◽  
Metformin Hcl

Background: Food and herbal extracts rich in Quercetin (QRT) are often self-medicated by diabetics and can potentially alter the pharmacokinetics (PK) of Metformin HCl (MET) and Canagliflozin (CNG) leading to food or herb-drug interactions and reduced therapeutic efficacy. However, the impact of these flavonoids on the pharmacokinetic behaviour of MET and CNG is mostly unknown. Methods: A simple one-step protein precipitation method was developed for the determination of MET and CNG from rat plasma. The mobile phase chosen was MeOH 65% and 35% water containing 0.1% formic acid at a flow rate of 1mL/min. Results: The retention time of MET, internal standard (Valsartan) and CNG was 1.83, 6.2 and 8.2 min, respectively. The method was found to be linear in the range of 200 - 8000 ng/mL for CNG and 100 = 4000 ng/ml for MET. Precision and accuracy of the method were below 20% at LLOQ and below 15% for LQC, MQC, and HQC. Conclusion: The method was successfully applied for the determination of PK of MET and CNG by using 100 μL of rat plasma. QRT co-administration affects the PK parameters of MET and CNG. This alteration in PK parameters might be of significant use for clinicians and patients.

The Microeconomics of Product Innovation

2018 ◽  
Author(s):  
Paul Stoneman ◽  
Eleonora Bartoloni ◽  
Maurizio Baussola
Keyword(s):  
Product Innovation ◽  
New Products ◽  
Goods And Services ◽  
Product Innovations ◽  
Microeconomic Analysis ◽  
Prime Objective ◽  
Price Measurement ◽  
The Impact

The prime objective of this book is the use microeconomic analysis to guide and provide insight into the generation and adoption of new products. Taking an approach that uses minimal formal mathematics, the volume initially addresses questions of definitions, sources, and extent of product innovation, differentiating between goods and services; hard and soft innovations; horizontal and vertical innovations; original, new to market, and new to firm innovations. The sources of product innovations (e.g. R&D, design, and creativity) are explored empirically, and the extent of such innovations is then pursued using survey and other data. Three chapters are devoted to the theoretical analysis of the demand for and supply of new products and to the determination of firms’ decisions to undertake product innovation. Later chapters encompass empirical evidence on the determination of the extent of product innovation, the diffusion of such innovation, the impact of product innovation on firm performance, price measurement, and welfare, while the final chapter addresses policy issues.

scholarly journals Viscoelastometry for detecting oral anticoagulants

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Philipp Groene ◽  
Daniela Wagner ◽  
Tobias Kammerer ◽  
Lars Kellert ◽  
Andreas Giebl ◽  
...  
Keyword(s):  
Healthy Volunteers ◽  
Prospective Observational Study ◽  
Oral Anticoagulants ◽  
Plasma Concentrations ◽  
Factor Xa ◽  
Clotting Time ◽  
Emergency Situations ◽  
Tissue Plasminogen ◽  
The Impact

Abstract Background Determination of anticoagulant therapy is of pronounced interest in emergency situations. However, routine tests do not provide sufficient insight. This study was performed to investigate the impact of anticoagulants on the results of viscoelastometric assays using the ClotPro device. Methods This prospective, observational study was conducted in patients receiving dabigatran, factor Xa (FXa)-inhibitors, phenprocoumon, low molecular weight heparin (LMWH) or unfractionated heparin (UFH) (local ethics committee approval number: 17–525-4). Healthy volunteers served as controls. Viscoelastometric assays were performed, including the extrinsic test (EX-test), intrinsic test (IN-test) Russel’s viper venom test (RVV-test), ecarin test (ECA-test), and the tissue plasminogen activator test (TPA-test). Results 70 patients and 10 healthy volunteers were recruited. Clotting time in the EX-test (CTEX-test) was significantly prolonged versus controls by dabigatran, FXa inhibitors and phenprocoumon. CTIN-test was prolonged by dabigatran, FXa inhibitors and UFH. Dabigatran, FXa inhibitors and UFH significantly prolonged CTRVV-test in comparison with controls (median 200, 207 and 289 vs 63 s, respectively; all p < 0.0005). Only dabigatran elicited a significant increase in CTECA-test compared to controls (median 307 vs 73 s; p < 0.0001). CTECA-test correlated strongly with dabigatran plasma concentration (measured by anti-IIa activity; r = 0.9970; p < 0.0001) and provided 100% sensitivity and 100% specificity for detecting dabigatran. Plasma concentrations (anti-XA activity) of FXa inhibitors correlated with CTRVV-test (r = 0.7998; p < 0.0001), and CTRVV-test provided 83% sensitivity and 64% specificity for detecting FXa inhibitors. Conclusions In emergency situations, ClotPro viscoelastometric assessment of whole-blood samples may help towards determining the presence and type of anticoagulant class that a patient is taking. Trial registration German clinical trials database ID: DRKS00015302.

scholarly journals Evaluation of Marblewood Dust’s (Marmaroxylon racemosum) Effect on Ignition Risk

2021 ◽  
Vol 11 (15) ◽  
pp. 6874
Author(s):  
Miroslava Vandličkova ◽  
Iveta Markova ◽  
Katarina Holla ◽  
Stanislava Gašpercová
Keyword(s):  
Particle Size ◽  
Dust Particles ◽  
Wood Dust ◽  
Sieve Analysis ◽  
Granulometric Analysis ◽  
Analysis Measurement ◽  
Risk Research ◽  
Minimum Ignition Temperature ◽  
The Impact

The paper deals with the selected characteristics, such as moisture, average bulk density, and fraction size, of tropical marblewood dust (Marmaroxylon racemosum) that influence its ignition risk. Research was focused on sieve analysis, granulometric analysis, measurement of moisture level in the dust, and determination of the minimum ignition temperatures of airborne tropical dust and dust layers. Samples were prepared using a Makita 9556CR 1400W grinder and K36 sandpaper for the purpose of selecting the percentages of the various fractions (<63, 63, 71, 100, 200, 315, 500 μm). The samples were sized on an automatic vibratory sieve machine Retsch AS 200. More than 65% of the particles were determined to be under 100 μm. The focus was on microfractions of tropical wood dust (particles with a diameter of ≤100 µm) and on the impact assessment of particle size (particle size <100 µm) on the minimum ignition temperatures of airborne tropical dust and dust layers. The minimum ignition temperature of airborne marblewood dust decreased with the particle size to the level of 400 °C (particle size 63 μm).

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