Results 61 to 70 of about 744,050 (371)

Anamorphic Fractional Fourier Transforming--Optical Implementation and Applications [PDF]

, 1995
Cataloged from PDF version of article.An additional degree of freedom is introduced to fractional-Fourier-transform systems by use of anamorphic optics. A different fractional Fourier order along the orthogonal principal directions is performed.
Bitran, Y., Dorsch, R. G., Ferreira, C., Garcia, J., Mendlovic, D., Ozaktas, H. M.   +5 more
core   +1 more source

CALPHAD‐Guided Prediction and Interpretation of Phase Formation in Ta–Mo–Cr–Ti–Al Refractory High‐Entropy Alloys

Advanced Engineering Materials, EarlyView.
This study designs Ta–Mo–Cr–Ti–Al refractory high‐entropy alloys with a disordered body‐centered‐cubic A2 crystal structure aiming for improved ductility, lower density, and oxidation resistance. Four alloy compositions are identified by thermodynamic calculations.
Kateryna Khanchych, Chongchong Tang, Carsten Schroer, Björn Schäfer, Judith Jung, Michael Dürrschnabel, Ute Jäntsch, Bronislava Gorr   +7 more
wiley   +1 more source

Fourier Series in Fractional Dimensional Space [PDF]

arXiv, 2022
In this paper, a Fourier series in fractional dimensional space is introduced for an arbitrarily periodic function $f(t;\alpha)$. We call it fractional Fourier series of the order $\alpha$. Extending the basis functions of the linear space into fractional one, by rotation transformation, we define a real and complex Fourier series and obtain their ...
arxiv  

Comparative Study of Experimental Methods for Measuring Thermal Properties of 100Cr6 Steel Powders

Advanced Engineering Materials, EarlyView.
This study investigates the thermal properties of 100Cr6 steel in both bulk and powder forms. Measuring the very low thermal conductivity typically exhibited by powders poses significant challenges. To address this, two novel measurement techniques—temperature gradient and finite laser pulse response—are introduced and evaluated by comparison with the ...
Junsheng Zhuo, Hagen P. Kohl, Dongmei Liu, Lisa Matthäus, Arne Bochmann, Aaron Berger, Sebastian Weber, Stefan Nolte, Stephanie Lippmann   +8 more
wiley   +1 more source

Uncertainty principles associated with the short time quaternion coupled fractional Fourier transform [PDF]

arXiv, 2023
In this paper, we extend the coupled fractional Fourier transform of a complex valued functions to that of the quaternion valued functions on $\mathbb{R}^4$ and call it the quaternion coupled fractional Fourier transform (QCFrFT). We obtain the sharp Hausdorff-Young inequality for QCFrFT and obtain the associated R\`enyi uncertainty principle.
arxiv  

Exact Relation Between Continuous and Discrete Linear Canonical Transforms [PDF]

, 2009
—Linear canonical transforms (LCTs) are a family of integral transforms with wide application in optical, acoustical, electromagnetic, and other wave propagation problems. The Fourier and fractional Fourier transforms are special cases of LCTs.
Figen S. Oktem, Haldun M. Ozaktas
core   +1 more source

The generalized fractional fourier transform [PDF]

2012 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 2012
A new transform, called the generalized fractional Fourier transform (gFrFT), is proposed. Originally, the eigenfunctions of the fractional Fourier transform (FrFT) are known as the Hermite Gaussian functions (HGFs). Besides, in optics, the HGFs are generalized to be the generalized Hermite Gaussian functions (gHGFs) and their adjoint functions (AgHGFs)
Soo-Chang Pei, Yun-Chiu Lai, Chun-Lin Liu   +2 more
openaire   +2 more sources

Efficient and Scalable Radiative Cooling for Photovoltaics Using Solution‐Processable and Solar‐Transparent Mesoporous Nanoparticles

Advanced Functional Materials, EarlyView.
Graded refractive index (GRI) structures are prepared from the layer‐by‐layer spray coating of the mesoporous SiO2 nanoparticles, showing high solar transparency and thermal emissivity. Under outdoor conditions, after 50 days, the GRI‐coated photovoltaics show on average 6.65 ± 1.48 °C lower than that of the non‐coated references, maintaining 80.9 ± 8 ...
Heesuk Jung, Sung Yoon Min, Byungsoo Kang, Yongseok Yoo, Jihun Jang, Yeoun‐Woo Jang, Hyojeong Choi, Hyeong Won Lee, Swarup Biswas, Yongju Lee, Mansoo Choi, Phillip Lee, Min Seok Jang, Hyeok Kim, Shu Yang   +14 more
wiley   +1 more source

A fractional Fourier transform–based channel estimation algorithm in single-carrier direct sequence code division multiple access underwater acoustic communication system

International Journal of Distributed Sensor Networks, 2019
Due to the complexity and variability of the underwater acoustic channel, the communication signal is affected by multi-path, time delay, and Doppler frequency shift.
Lin Zhou, Qingsheng Zhao, Shukai Chi, Yanlong Li, Lanjun Liu, Qianxiang Yu   +5 more
doaj   +1 more source

Fourier transforms of hypercomplex signals [PDF]

, 2011
An overview is given to a new approach for obtaining generalized Fourier transforms in the context of hypercomplex analysis (or Clifford analysis). These transforms are applicable to higher-dimensional signals with several components and are different ...
De Bie, Hendrik, De Schepper, Nele
core   +1 more source