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السجلات المعروضة 26595 -- 26614 من 49977
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Volatile Components of the Phaeophyceae Hormophysa cuneiformis Growing Along Qatar Coasts
( Qatar University , 2007 , Article)The present work deals with the study on volatile compounds from the brown alga Hormophysa cuneiformis collected from the Northwest coast of Qatar on May 2002. Two extraction methods have been used: conventional hydrodistillation ... -
VOLATILITY ESTIMATION IN MISSING AT RANDOM HIGH-FREQUENCY FINANCIAL TIME SERIES
(2023 , Master Thesis)More than 15 years ago, the capital markets have seen significant development, introducing high-frequency trading and a shift of market towards high-frequency and algorithm trading. It was always believed that high-frequency ... -
Volatility forecasting, downside risk, and diversification benefits of Bitcoin and oil and international commodity markets: A comparative analysis with yellow metal
( Elsevier Inc. , 2019 , Article)This study examines the diversification and hedging properties of Bitcoin (BTC) and gold assets for oil and S&P GSCI investors. We model and forecast the volatility performance of the pairs BTC–oil, gold–oil, BTC–S&P GSCI, ... -
Volatility forecasting, downside risk, and diversification benefits of Bitcoin and oil and international commodity markets: A comparative analysis with yellow metal
( Elsevier , 2019 , Article)This study examines the diversification and hedging properties of Bitcoin (BTC) and gold assets for oil and S&P GSCI investors. We model and forecast the volatility performance of the pairs BTC-oil, gold-oil, BTC-S&P GSCI, ... -
Volatility transmission across currencies and commodities with US uncertainty measures
( Elsevier Inc. , 2016 , Article)This paper uses the Multi-chain Markov Switching model (MCMS) conditioned on US uncertainty measures (VIX, VIX-oil and FSI) to examine the patterns of volatility transmission across the resource, major and safe haven ... -
Voltage and congestion control in active distribution networks using fast sensitivity analysis
( Institute of Electrical and Electronics Engineers Inc. , 2020 , Conference Paper)Active distribution networks will meet new challenges in voltage and congestion control due to the high penetration levels of distributed generations (DG). Optimal voltage control techniques are mainly based on the relation ... -
The Voltage Collapse Problem Based On The Power System Loadability
( Qatar University , 1997 , Article)This paper addresses the problem of voltage instability at which the power system reaches its maximum admissible load. A voltage collapse proximity indicator (VCPI) is derived and its performance is investigated. The VCPI ... -
Voltage control in distribution networks using current source converter STATCOM based on state feedback controller and Kalman filter
( Institute of Electrical and Electronics Engineers Inc. , 2018 , Conference Paper)In transmission and Medium-Voltage (MV) distribution systems, the voltage can be controlled by reactive power due to the high X/R ratio of the cables/overhead lines. Maintaining voltage within a fixed limit is critical to ... -
Voltage dependence of the Ca2+ transient in endocardial and epicardial myocytes from the left ventricle of Goto Kakizaki type 2 diabetic rats
( Springer New York LLC , 2018 , Article)Diabetes mellitus is a major global health disorder and, currently, over 450 million people have diabetes with 90% suffering from type 2 diabetes. Left untreated, diabetes may lead to cardiovascular diseases which are a ... -
Voltage Independent Reactive Current Based Sensor for Static VAr Control Applications
( Institute of Electrical and Electronics Engineers Inc. , 2023 , Article)The use of renewable energy-based converters is continuously increasing in modern power systems which inject voltage harmonics in the line. In this work, a novel, simple technique based on a binary (on/off) control of an ... -
Voltage Profiling and Control of a Sub-Transmission Network with Integrated Renewable Energy Sources-A Case Study
( Institute of Electrical and Electronics Engineers Inc. , 2021 , Conference Paper)Traditional power generation methods are causing environmental issues. Some of the other drawbacks like line loading will increase the losses and the response time will be very high, which cannot be supporting the future ... -
Voltage sag mitigation employing dynamic voltage restorer with minimum energy requirements: Analysis and implementation
( Institution of Engineering and Technology , 2016 , Conference Paper)The objective of this paper is to design and implement an economical and efficient single phase dynamic voltage restorer (DVR) that compensates for voltage sag conditions. In this paper, different techniques of voltage sag ... -
Voltage sensorless current control of low power inverter-based distributed generation systems
( Institute of Electrical and Electronics Engineers Inc. , 2014 , Conference Paper)The control of power electronic converters is subjected to several challenges as measurement sensors drift, malfunction in harsh environments, non-ideal grid, and performance degradation due to the delay of discrete control ... -
Voltage stability evaluation of real power transmission system using singular value decomposition technique
( IEEE , 2008 , Conference Paper)Voltage stability is an important factor that needs to be taken into consideration during the planning and operation of power systems in order to avoid voltage collapse and subsequently partial or full system blackout. ... -
Voltage Stability Margin Identification Using Local Measurements And Linear Kalman Filter
( Qatar University , 2002 , Article)Voltage stability investigation is of a great importance for long-term electric load expansion as well as power system operation. This paper presents a new algorithm for identification of voltage instability in a specified ... -
Voltage/load Control Strategy for Smart Distribution Grids with a High Penetration of Renewable Energy Sources
( European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ) , 2016 , Article)The exponential increase of renewable energy sources (RESs) penetration in the power grid introduces the of voltage instability when RESs are integrated into medium and low voltage networks. This paper proposes a state-machine ... -
Voluntary disclosure in the annual reports of an emerging country: The case of Qatar
( Elsevier Ltd , 2009 , Article)This study sets out to examine empirically the determinants of voluntary disclosure in the annual reports of 25 listed firms of Doha Securities Market (DSM) in Qatar forming approximately 86% of the total firms incorporated ... -
Voluntary risk disclosure and values of FTSE350 firms: the role of an industry-based litigation risk
( Inderscience Publishers , 2021 , Article)There is conflicting research on whether litigation risk affects voluntary disclosure positively or negatively. This study thus aims to examine how litigation risk affects the voluntary disclosure of risk information. It ... -
Volunteers of Oman during the Corona Crisis: An Exploratory Study in the Sociology of Altruism
( Gulf Studies center - College of Arts & Sciences - Qatar University , 2020 , Conference Paper)Volunteering is a major aspect of contemporary globalized societies. It has long been an indicator for proper functioning of society at large. Further, it made notable difference for individuals, groups and organizations. ... -
VOPcPhO:P3HT composite micro-structures with nano-porous surface morphology
( Elsevier B.V. , 2017 , Article)In this paper, composite micro-structures of Vanadyl 2,9,16,23-tetraphenoxy-29H,31H-phthalocyanine) (VOPcPhO) and Poly (3-hexylthiophene-2,5-diyl) (P3HT) complex with nano-porous surface morphology have been developed by ...
