نتایج جستجو برای: direct system

تعداد نتایج: 2570514  

ژورنال: Journal of Railway Research 2018
Fazel, Seyed Saeed, Foiadelli, Federica, Jafari Kaleybar, Hamed, Madadi Kojabadi, Hossein, Brenna, Morris ,

Abstract Traditional railway power supply systems impose substantial power quality problems (PQ) on the utility network, such as unbalance, harmonics and a large amount of reactive power. This paper proposes a topology based on three-phase to single-phase modular multilevel converters (MMC) to obviate these problems. The MMC based traction substations (TSS) are connected directly to the utili...

2006
William S. Helton

The acquisition of expertise is an area of controversy between those seeing a strong influence from genetics, inherent talent, and those who deny that genetics plays much of a role. Because the genetics and early life experiences of humans are not open to direct manipulation, human studies are of limited utility in this debate. Studies employing non-humans as expert models may prove useful in r...

2008
M. Manuela M. Raposo A. Maurício C. Fonseca G. Kirsch

Seven new donor/acceptor oligothiophenes 1-2 were synthesized by Stille coupling in moderate to good yields. Compounds 1-2 were completely characterized by the usual spectroscopic methods. In agreement with the electrochemical and the spectroscopic studies for this compounds the new derivatives prepared, can find application for manufacturing new materials with strong non-linear optical (NLO) p...

2016
Natalia Vélez Yuan Chang Leong Chelsey Pan Jamil Zaki Hyowon Gweon

We often make decisions on behalf of others, such as picking out gifts or making restaurant recommendations. Yet, without direct access to others’ preferences, our choices on behalf of others depend on what we think they like. Across two experiments, we examined whether and how accurately people are able to infer others’ preferences by observing their choices. Our results suggest that people ar...

Journal: :Applied optics 1973
N George A Jain

The occurrence and smoothing of speckle are studied as a function of the line width for a highly collimated illuminating source. A general theory is presented for speckling in the image of a partially diffuse, phase type of object, which has a variable number of random scattering centers per resolution element. Then, an expression is derived for the wavelength spacing required to decouple the s...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه اصفهان 1389

implicit and unobserved errors and vulnerabilities issues usually arise in cryptographic protocols and especially in authentication protocols. this may enable an attacker to make serious damages to the desired system, such as having the access to or changing secret documents, interfering in bank transactions, having access to users’ accounts, or may be having the control all over the syste...

1992
Steven R. Snapp Stephen E. Smaha Daniel M. Teal Tim Grance

S. Abdollahpour S.M.H. Karparvarfard

ABSTRACT-In conventional agriculture, a large amount of energy is consumed in fuel consumption and depreciation of farm tractors and any other farm equipment mostly in tillage and planting operations. The main purpose of this research was to evaluate a till-planting unit equipped with three jointers. This unit was expected to act as conventional furrow openers such as shovel openers tilling the...

Journal: :DEStech Transactions on Computer Science and Engineering 2017

Journal: :Journal of Applied Research and Technology 2014

20042005200620072008200920102011201220132014201520162017201820192020202120222023050000100000150000

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید