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21.
Mehrdad Djavid Mohammad Hadi Tavakoli Dastjerdi Moab Rajan Philip Dipayan Datta Choudhary Thi Tan Pham Abdallah Khreishah Hieu Pham Trung Nguyen 《Photonic Network Communications》2018,35(1):90-96
We present, for the first time, the design of a low-cross talk scalable permutation switch employing photonic crystal ring resonators in an optical network. Through this novel approach, the transition between different states of the \(2 \times 2\) optical switch, as the basic element, is achieved by applying different operating wavelengths. Subsequently, the shuffling mechanisms in \(3 \times 3\) and \(4 \times 4\) optical networks are realized by controlling the position of photonics crystal ring resonators. Lowest cross talk levels of 6 and 5% are obtained for “bar” and “cross” switching states, respectively. 相似文献
22.
A relation between the types of symmetries that exist in signal and Fourier transform domain representations is derived for continuous as well as discrete domain signals. The symmetry is expressed by a set of parameters, and the relations derived in this paper will help to find the parameters of a symmetry in the signal or transform domain resulting from a given symmetry in the transform or signal domain respectively. A duality among the relations governing the conversion of the parameters of symmetry in the two domains is also brought to light. The application of the relations is illustrated by a number of two-dimensional examples.Notation
R
the set of real numbers
-
R
m
R × R × ... × R m-dimensional real vector space
-
continuous domain real vector
-
L
{¦ – i , i = 1,2,..., m}
-
m-dimensional frequency vector
-
W
{ – i ,i=1,2,..., m}
-
m-dimensional normalized frequency vector
- P
{¦ – i , i=1,2,...,m}
-
g(ol)
g (1,2,...,
m
) continuous domain signal
-
()
(
1
2,...,
m
)=G (j
1,j
2,..., j
m
) Fourier transform ofg (ol)
-
(A,b,,,) parameters ofT- symmetry
-
N
the set of integers
-
N
m
N × N × ... × N m-dimensional integer vector spacem-dimensional lattice
-
h(n)
h (n
1,.,n
m
) discrete domain signal
-
H()
Fourier transform ofh (n)
-
v
1,v
2,..., vm
m sample-direction and interval vectors
-
V
(v
1
v
2 ...v
m
) sampling basis matrix
- [x]*
complex conjugate ofx
- detA
determinant ofA
-
X
{x¦ – x
i
, i=1,2,..., m}
-
A
–t
[A
–1]
t
,t stands for transpose
This work was supported in part by the Natural Sciences and Engineering Research Council of Canada under Grant A-7739 to M. N. S. Swamy and in part by Tennessee Technological University under its Faculty Research support program to P. K. Rajan. 相似文献
23.
24.
Manisha Bhandari Rajan Sharma Savita Sharma 《International Journal of Food Science & Technology》2023,58(1):367-377
The current investigation was focused on developing and assessing the influence of different herbs (Ocimum sanctum, Withania somnifera, Bacopa monnieri and Asparagus racemosus) on bio-functional and structural characteristics of semolina-based pasta. Pasta were enriched with 2.5, 5, 7.5 and 10% herbs and significant difference (P < 0.05) in functional properties of blends, cooking quality of pasta, bioactive profile and antioxidant potential, in vitro nutrient digestibility and colour profile were noted. Herbs-enriched pasta showed modified functional properties and enhanced bioactive constituents. Modification in structural and molecular structures of control and 5% herbs-incorporated pasta was shown by Scanning Electron Microscopy and Attenuated Total Reflectance-Fourier Transform Infrared. Further, principal component analysis and agglomerative hierarchical clustering were employed to authenticate the difference in the incorporation of herbs and observations. The results suggest that herbs could be served as potential food components in valorised products of cereals. 相似文献
25.
Bhavadharini Boopathy Anbarasan Rajan Jaspin Stephen Mahendran Radhakrishnan 《International Journal of Food Science & Technology》2023,58(1):502-511
Shape transforming foods are an emerging area of interest that could be customised according to consumer needs with the desirable structure and reduced package space. The current work aims to investigate the shape transformation behaviour of a 2D xerogel developed from rice hydrogel at the concentration of 4% and 90 °C. This flat xerogel is coated with ethyl cellulose as constraint material in the form of linear equally spaced strips. Immersing the xerogels in hot water over a temperature of 70 °C, resulted in a 3D transformation of the discs in 12 s (Video S1 ). The transformation is achieved owing to xerogel's increased swelling power (0.27–0.78) due to the anisotropic nature. This is confirmed by the SEM images of top (smooth) and bottom (rough) xerogel. In order to characterise the process of shape transformation bending analysis was done wherein a significant difference in bending angle (35.86–63.10°), height (24.73–50.26 mm), curvature (0.57–2.38 μ mm−1) and end-to-end distance (118.23–15.11 mm) from 2 to 12 s. The formed 3D shape was similar to the commercial tubular (penne) pasta. This study opens up the utilisation of less concentrated rice xerogel in shape transformation for designing engineered food. 相似文献
26.
The present study was evaluated using the following in vitro antioxidant methods: 2,2′-azinobis (3-ethyl-benzothiozoline)-6-sulfonic acid disodium salt, phosphomolybdenum, ferric reducing antioxidant power, metal ion chelating activity, super oxide anion radical scavenging, hydrogen peroxide, and hydroxyl radical. Among these assays, acetone extract showed maximum free radical scavenging activity in 2,2′-azinobis (3-ethyl-benzothiozoline)-6-sulfonic acid disodium salt, phosphomolybdenum, metal ion chelating, superoxide anion, hydrogen peroxide, and hydroxyl radical assays. Moreover, the physiochemical, nutritional, and anti-nutritional parameters were analyzed. Its qualitative and quantitative composition was studied by gas chromatography-mass spectroscopy and out of 27 peaks, 27 compounds were identified. These compounds have the property of antioxidant, antimicrobial, and anti-inflammatory activity. 相似文献
27.
28.
29.
Xinxiang Zhang Dinesh Rajan Brett Story 《Computer-Aided Civil and Infrastructure Engineering》2019,34(11):951-971
Computer‐vision and deep‐learning techniques are being increasingly applied to inspect, monitor, and assess infrastructure conditions including detection of cracks. Traditional vision‐based methods to detect cracks lack accuracy and generalization to work on complicated infrastructural conditions. This paper presents a novel context‐aware deep convolutional semantic segmentation network to effectively detect cracks in structural infrastructure under various conditions. The proposed method applies a pixel‐wise deep semantic segmentation network to segment the cracks on images with arbitrary sizes without retraining the prediction network. Meanwhile, a context‐aware fusion algorithm that leverages local cross‐state and cross‐space constraints is proposed to fuse the predictions of image patches. This method is evaluated on three datasets: CrackForest Dataset (CFD) and Tomorrows Road Infrastructure Monitoring, Management Dataset (TRIMMD) and a Customized Field Test Dataset (CFTD) and achieves Boundary F1 (BF) score of 0.8234, 0.8252, and 0.7937 under 2‐pixel error tolerance margin in CFD, TRIMMD, and CFTD, respectively. The proposed method advances the state‐of‐the‐art performance of BF score by approximately 2.71% in CFD, 1.47% in TRIMMD, and 4.14% in CFTD. Moreover, the averaged processing time of the proposed system is 0.7 s on a typical desktop with Intel® Quad‐Core? i7‐7700 CPU@3.6 GHz Processor, 16GB RAM and NVIDIA GeForce GTX 1060 6GB GPU for an image of size 256 × 256 pixels. 相似文献
30.
Payton Beeler Nicholas O. Jensen Soyoung Kim Amy Robichaux-Viehoever Bradley L. Schlaggar Deanna J. Greene Kevin J. Black Rajan K. Chakrabarty 《Journal of the Royal Society Interface》2022,19(187)
Tics manifest as brief, purposeless and unintentional movements or noises that, for many individuals, can be suppressed temporarily with effort. Previous work has hypothesized that the chaotic temporal nature of tics could possess an inherent fractality, that is, have neighbour-to-neighbour correlation at all levels of timescale. However, demonstrating this phenomenon has eluded researchers for more than two decades, primarily because of the challenges associated with estimating the scale-invariant, power law exponent—called the fractal dimension Df—from fractional Brownian noise. Here, we confirm this hypothesis and establish the fractality of tics by examining two tic time series datasets collected 6–12 months apart in children with tics, using random walk models and directional statistics. We find that Df is correlated with tic severity as measured by the YGTTS total tic score, and that Df is a sensitive parameter in examining the effect of several tic suppression conditions on the tic time series. Our findings pave the way for using the fractal nature of tics as a robust quantitative tool for estimating tic severity and treatment effectiveness, as well as a possible marker for differentiating typical from functional tics. 相似文献