857 research outputs found
Design and fabrication of double pancake coil using 2G wire for conduction cooled superconducting magnet
AbstractA large bore double pancake coil(DPC) was designed and tested with 2G HTS wire to develop the conduction cooled superconducting magnet with central field intensity of 3 T at 20K operating temperature and clear bore of 100mm at room temperature. The effect of insulation between turns of double pancake coils was tested. Two double pancake coils with and without turn to turn insulation were wound using 4mm wide 2G conductor. A temporary result suggests that the coil wound without electrical insulation can be protected from higher over current and shows improved stability
The effect of wavy leading edges on aerofoil-gust interaction noise
High-order accurate numerical simulations are performed to investigate the effects of wavy leading edges (WLEs) on aerofoil–gust interaction (AGI) noise. The present study is based on periodic velocity disturbances predominantly in streamwise and vertical directions that are mainly responsible for the surface pressure fluctuation of an aerofoil. In general, the present results show that WLEs lead to reduced AGI noise. It is found that the ratio of the wavy leading-edge peak-to-peak amplitude (LEA) to the longitudinal wavelength of the incident gust (?g) is the most important factor for the reduction of AGI noise. It is observed that there exists a tendency that the reduction of AGI noise increases with LEA/?g and the noise reduction is significant for LEA/?g?0.3. The present results also suggest that any two different cases with the same LEA/?g lead to a strong similarity in their profiles of noise reduction relative to the straight leading-edge case. The wavelength of wavy leading edges (LEW), however, shows minor influence on the reduction of AGI noise under the present gust profiles used. Nevertheless, the present results show that a meaningful improvement in noise reduction may be achieved when 1.0?LEW/?g?1.5. In addition, it is found that the beneficial effects of WLEs are maintained for various flow incidence angles and aerofoil thicknesses. Also, the WLEs remain effective for gust profiles containing multiple frequency components. It is discovered in this paper that WLEs result in incoherent response time to the incident gust across the span, which results in a decreased level of surface pressure fluctuations, hence a reduced level of AGI noise
Path finding strategies in scale-free networks
We numerically investigate the scale-free network model of Barab{\'a}si and
Albert [A. L. Barab{\'a}si and R. Albert, Science {\bf 286}, 509 (1999)]
through the use of various path finding strategies. In real networks, global
network information is not accessible to each vertex, and the actual path
connecting two vertices can sometimes be much longer than the shortest one. A
generalized diameter depending on the actual path finding strategy is
introduced, and a simple strategy, which utilizes only local information on the
connectivity, is suggested and shown to yield small-world behavior: the
diameter of the network increases logarithmically with the network size
, the same as is found with global strategy. If paths are sought at random,
is found.Comment: 4 pages, final for
Dynamic characteristics of flow meters for fuel consumption measurement in ships
The dynamic characteristics of various flow meters for fuel
consumption measurement aboard shipswere evaluated. The
flow rate was measured using the Korea Research Institute of
Standards and Science (KRISS) oil flow standard system using
K-oil(density : 0.804 g/cm3, viscosity : 3.679 cSt), which has
similar fluid properties as diesel oil. The flow meters were tested
in a test bed that simulated the vibration conditions in ships. The
vibration conditions were established in accordance to vibration
standard IEC 60068-2-6 as follows: a±0.7g acceleration and 30
Hz frequency. The K-factors (mL/pulse) of various flow meters
(PD meter, turbine flow meter, Coriolis flow meter, and
ultrasonic flow meter) were obtained for various flow rates (60
L/h ~ 300 L/h). The PD meter, Coriolis flow meter, and
ultrasonic flow meter were found to have almost constant Kfactors
according to the flow rates. However, the K-factor of the
turbine flow meter was reduced at a low flow rate owing to
bearing friction in the turbine blade. The flow rate errors of the
PD meter, Coriolis flow meter, and ultrasonic flow meter were
found to be under ±0.5 % with and without vibration. However,
the flow rate error of the turbine flow meter was approximately
-4.3 % at a low flow rate (60 L/h) owing to the friction effect.
The Coriolis flow meter had the lowest flow rate error (< 0.1%)
according to the flow rate. The vibration influenced the flow rate
error of the Coriolis flow meter at high flow rates owing to its
measuring principle. However, the difference in flow rate errors
was a negligible value (0.05 %) with and without vibration.
Therefore, we confirmed that the PD meter, turbine meter,
Coriolis flow meter and ultrasonic flow meter could be used for
measuring flow rates in ships with a ±0.5 % flow rate error.Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .International centre for heat and mass transfer.American society of thermal and fluids engineers
Cryptococcal Meningoencephalitis Presenting as Cerebell itis - A case report -
, , We herein report an elderly patient with cryptococcosis in the nervous
system who presented with cerebellar dysfunction and showed cerebellar parenchymal
lesion with adjacent focal meningeal enhancement on the brain CT and the
serial brain MRls. The cerebellar lesion suggests cryptococcal inflammatory reaction
or a cerebellar infarction from the arteritis of a branch of the left superior cerebellar
artery. This clinical and neuroimaging finding of cerebellitis has not been reported in
cryptococcosis. We think cryptococcosis would be included in the differential
diagnosis of cerebellitis
SIR performance evaluation of MB-OFDM UWB system with residual timing offset
Signal-to-interference ratio (SIR) performance of a multiband orthogonal frequency division multiplexing ultra-wideband system with residual timing offset is investigated. To do so, an exact mathematical derivation of the SIR of this system is derived. It becomes obvious that, unlike a cyclic prefixing based system, a zero padding based system is sensitive to residual timing offset.This work was supported by the National Research Foundation of Korea (NRF) grant, funded by the Korean government (MSIP) no. 2010-0018116.Islam, SMR.; Ullah, S.; Lloret, J.; Ullah, N.; Kwak, KS. (2015). SIR performance evaluation of MB-OFDM UWB system with residual timing offset. Electronics Letters. 51(5):427-429. https://doi.org/10.1049/el.2014.3967S42742951
All-electron magnetic response with pseudopotentials: NMR chemical shifts
A theory for the ab initio calculation of all-electron NMR chemical shifts in
insulators using pseudopotentials is presented. It is formulated for both
finite and infinitely periodic systems and is based on an extension to the
Projector Augmented Wave approach of Bloechl [P. E. Bloechl, Phys. Rev. B 50,
17953 (1994)] and the method of Mauri et al [F. Mauri, B.G. Pfrommer, and S.G.
Louie, Phys. Rev. Lett. 77, 5300 (1996)]. The theory is successfully validated
for molecules by comparison with a selection of quantum chemical results, and
in periodic systems by comparison with plane-wave all-electron results for
diamond.Comment: 25 pages, 4 tables, submitted to Physical Review
Expression profiling of cyclin B1 and D1 in cervical carcinoma
Aim: Cyclins are a family of regulatory proteins that play a key role in controlling the cell cycle. Abnormalities of cell cycle regulators, including cyclins and cyclin dependent kinases, have been reported in various malignant tumors. This study was undertaken to quantitatively detect cyclin B1 and D1 in cervical cancer. Methods: A quantitative real-time reverse transcription polymerase chain reaction and Western blot assay were used to analyze the expression of cyclin B1/D1 mRNA and proteins, respectively, in fresh invasive cervical cancer (n = 41) and normal cervical tissues (n = 10). Results: There was significantly greater cyclin B1 expression in invasive cervical cancer than in normal cervical tissue (P = 0.019). However, cyclin D1 expression was not significantly different. A Western blot assay yielded similar results. Conclusion: Our results were consistent with the concept that up-regulation of cyclin B1 expression occurred in cervical cancer and an aberrant expression of cyclin B1 might play an important role in cervical carcinogenesis.Цель: циклины представляют собой семейство регуляторных белков, контролирующих клеточный цикл. Наличие
функциональных и структурных нарушений регуляторов клеточного цикла (циклинов и циклинзависимых киназ) было
отмечено в клетках различных злокачественных новообразований. Целью данного исследования было проведение
количественного определения циклинов B1 и D1 в клетках рака шейки матки. Методы: определение уровня экспрессии
циклинов B1/D1 (mRNA и белков соответственно) в свежеполученных клетках инвазивного рака шейки матки (n = 41) и
нормальной ткани шейки матки (n = 10) проводили методами RT-PCR в режиме реального времени и Вестерн-блот анализа.
Результаты: отмечен более высокий уровень экспрессии гена циклина В1 в клетках инвазивного рака шейки матки, чем в
клетках нормальной ткани (P = 0,019). Не выявлены значительные различия в уровне экспрессии гена циклина D1. При
Вестерн-блот анализе получены аналогичные результаты. Выводы: результаты исследования подтверждают концепцию
об активации экспрессии циклина В1 при раке шейки матки. Аберрантная экспрессия циклина В1 может играть важную
роль при злокачественной трансформации эпителия шейки матки
Synchronization and resonance in a driven system of coupled oscillators
We study the noise effects in a driven system of globally coupled
oscillators, with particular attention to the interplay between driving and
noise. The self-consistency equation for the order parameter, which measures
the collective synchronization of the system, is derived; it is found that the
total order parameter decreases monotonically with noise, indicating overall
suppression of synchronization. Still, for large coupling strengths, there
exists an optimal noise level at which the periodic (ac) component of the order
parameter reaches its maximum. The response of the phase velocity is also
examined and found to display resonance behavior.Comment: 17 pages, 3 figure
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