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Journal articles on the topic 'IDFT'

Author: Grafiati

Published: 4 June 2021

Last updated: 7 February 2022

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1

YONEDA, SHOJIRO, ISAO NAKANISHI, ITSUO SASAKI, and AKIO OGIHARA. "Switched-capacitor DFT and IDFT circuit." International Journal of Electronics 67, no. 6 (December 1989): 839–51. http://dx.doi.org/10.1080/00207218908921134.

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2

Reimer, Tyson, Mario Solis-Nepote, and Stephen Pistorius. "The impact of the inverse chirp z-transform on breast microwave radar image reconstruction." International Journal of Microwave and Wireless Technologies 12, no. 9 (April 28, 2020): 848–54. http://dx.doi.org/10.1017/s1759078720000379.

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This work examines the impact of the inverse chirp z-transform (ICZT) for frequency-to-time-domain conversion during image reconstruction of a pre-clinical radar-based breast microwave imaging system operating over 1–8 GHz. Two anthropomorphic breast phantoms were scanned with this system, and the delay-multiply-and-sum beamformer was used to reconstruct images of the phantoms, after using either the ICZT or the inverse discrete Fourier transform (IDFT) for frequency-to-time domain conversion. The contrast, localization error, and presence of artifacts in the reconstructions were compared. The use of the IDFT resulted in prominent ring artifacts that were not present when using the ICZT, and the use of the ICZT resulted in higher contrast between the tumor and clutter responses. In one of the phantoms, the tumor response was only visible in reconstructions that used the ICZT. The use of the ICZT evaluated with a time-step size of 11 ps resulted in the reduction of prominent artifacts present when using the IDFT and the successful identification of the tumor response in the reconstructed images.

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3

Ghassemi, A., and T. A. Gulliver. "Low-Complexity Distortionless Techniques for Peak Power Reduction in OFDM Communication Systems." Journal of Computer Networks and Communications 2012 (2012): 1–13. http://dx.doi.org/10.1155/2012/929763.

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A high peak-to-average power ratio (PAPR) is one of the major drawbacks to using orthogonal frequency division multiplexing (OFDM) modulation. The three most effective distortionless techniques for PAPR reduction are partial transmit sequence (PTS), selective mapping (SLM), and tone reservation (TR). However, the high computational complexity due to the inverse discrete Fourier transform (IDFT) is a problem with these approaches. Implementation of these techniques typically employ direct computation of the IDFT, which is not the most efficient solution. In this paper, we consider the development and performance analysis of these distortionless techniques in conjunction with low-complexity IFFT algorithms to reduce the PAPR of the OFDM signal. Recently, proposed IFFT-based techniques are shown to substantially reduce the computational complexity and improve PAPR performance.

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4

A. Alwan, Majid. "New Design of Low Complexity Multipliers in DFT/IDFT." Basrah journal of engineering science 20, no. 2 (March 1, 2020): 66–73. http://dx.doi.org/10.33971/bjes.20.2.8.

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5

Gunther, J. H. "Simultaneous DFT and IDFT of real N-point sequences." IEEE Signal Processing Letters 9, no. 8 (August 2002): 245–46. http://dx.doi.org/10.1109/lsp.2002.803006.

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6

Feng, Qi, Jiyong Pang, Marco Maso, Merouane Debbah, and Wen Tong. "IDFT-VFDM for Supplementary Uplink and LTE-NR Co-Existence." IEEE Transactions on Wireless Communications 19, no. 5 (May 2020): 3435–48. http://dx.doi.org/10.1109/twc.2020.2973641.

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7

Salous, S. "The design of linear phase FIR filters using the IDFT." IEEE Transactions on Education 41, no. 3 (1998): 229–31. http://dx.doi.org/10.1109/13.704553.

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8

Xiao, Xiangli, Junjian Huang, Yushu Zhang, and Xing He. "Efficient and Secure Outsourcing of DFT, IDFT, and Circular Convolution." IEEE Access 7 (2019): 60126–33. http://dx.doi.org/10.1109/access.2019.2915196.

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9

Ding, Guangyao, Qi Feng, Jiyong Pang, Rui Yin, and Guanding Yu. "Unitary Matrix Method for PAPR Reduction of IDFT-VFDM Signals." IEEE Wireless Communications Letters 9, no. 12 (December 2020): 2107–11. http://dx.doi.org/10.1109/lwc.2020.3014259.

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10

Zhang, Zongyu, Chengwei Zhou, Yujie Gu, Jinfang Zhou, and Zhiguo Shi. "An IDFT approach for coprime array direction-of-arrival estimation." Digital Signal Processing 94 (November 2019): 45–55. http://dx.doi.org/10.1016/j.dsp.2019.05.006.

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11

Wu, Chih-Feng, Chun-Hung Chen, and Muh-Tian Shiue. "A Design of Input-Decimation Technique for Recursive DFT/IDFT Algorithm." IEEE Transactions on Circuits and Systems I: Regular Papers 66, no. 12 (December 2019): 4713–26. http://dx.doi.org/10.1109/tcsi.2019.2931794.

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12

El-Barbary, Mohamed, Fatma Newagy, and Ismail Hafez. "A Novel IDFT/DFT Based Transceiver for Faster than Nyquist Signaling Optimization." Wireless Personal Communications 97, no. 4 (November 13, 2017): 5643–56. http://dx.doi.org/10.1007/s11277-017-4799-6.

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13

Kang, Seog. "An OFDM with 3-D signal mapper and 2-D IDFT modulator." IEEE Communications Letters 12, no. 12 (December 2008): 871–73. http://dx.doi.org/10.1109/lcomm.2008.081197.

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14

An, Changyoung, and Heung-Gyoon Ryu. "Design and Performance Evaluation of OTFS Modulation System using 2D iDFT and DFT." Journal of the Institute of Electronics and Information Engineers 54, no. 9 (September 30, 2017): 14–20. http://dx.doi.org/10.5573/ieie.2017.54.9.14.

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15

Wang, Tingjian, Liqin Wang, and Xiaoli Zhao. "IDFT numerical simulation method for Gaussian rough surface with relatively large correlation length." Transactions of Tianjin University 21, no. 3 (June 2015): 216–22. http://dx.doi.org/10.1007/s12209-015-2422-z.

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16

Manton, J. H. "Dissecting OFDM: the independent roles of the cyclic prefix and the IDFT operation." IEEE Communications Letters 5, no. 12 (December 2001): 474–76. http://dx.doi.org/10.1109/4234.974490.

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17

JWA, J. W. "An OFDM Scheme with Pre-IDFT/DFT on Frequency-Selective Rayleigh Fading Channels." IEICE Transactions on Communications E88-B, no. 7 (July 1, 2005): 3073–77. http://dx.doi.org/10.1093/ietcom/e88-b.7.3073.

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18

Wu, Chih-Feng, Chun-Hung Chen, and Muh-Tian Shiue. "Corrections to “A Design of Input-Decimation Technique for Recursive DFT/IDFT Algorithm”." IEEE Transactions on Circuits and Systems I: Regular Papers 67, no. 6 (June 2020): 2152. http://dx.doi.org/10.1109/tcsi.2020.2987537.

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19

Li, Chen Wu, Jian Zhang, Qin Xie, and Xiao Hong Zhang. "Carrier Modulation Technology Based on Orthogonal Frequency Division Multiplexing." Advanced Materials Research 774-776 (September 2013): 1671–76. http://dx.doi.org/10.4028/www.scientific.net/amr.774-776.1671.

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This paper first analyzes the transmission characteristics of low-voltage power line channels with the focus on the study of carrier modulation technology regarding the power line communication part, then proposes the orthogonal frequency division multiplexing technology that serves for the digital communication of family network power line communication gateways, analyzes the OFDM system principle, actulizes OFDM modulation and demodulation through discrete Fourier transform (DFT) and inverse discrete Fourier transform (IDFT), and build the OFDM simulation model. Finally, a specific plan of using power lines as the family network transmission media is proposed.

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20

Lin, Chi-Hsiang, Chun-Ting Lin, Chia-Chien Wei, and Sien Chi. "DFT/IDFT-free receiving scheme for spread-OFDM signals employing low-sampling-rate ADCs." Optics Express 25, no. 22 (October 26, 2017): 27750. http://dx.doi.org/10.1364/oe.25.027750.

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21

Fertner, Antoni, Mattias Hyll, and Anders Orling. "Efficient computation of the DFT and IDFT in communication systems using Discrete Multitone modulation." Journal of Communications and Networks 1, no. 2 (June 1999): 86–88. http://dx.doi.org/10.1109/jcn.1999.6596751.

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22

VAN, L. D., C. T. LIN, and Y. C. YU. "VLSI Architecture for the Low-Computation Cycle and Power-Efficient Recursive DFT/IDFT Design." IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences E90-A, no. 8 (August 1, 2007): 1644–52. http://dx.doi.org/10.1093/ietfec/e90-a.8.1644.

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23

Waqas, Ghulam Jilani, Ishtiaq Ahmad, Muhammad Kashif Samee, Muhammad Nasir Khan, and Ali Raza. "A hybrid OFDM–CDMA-based robust image watermarking technique." International Journal of Wavelets, Multiresolution and Information Processing 18, no. 06 (August 20, 2020): 2050043. http://dx.doi.org/10.1142/s0219691320500435.

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Digital watermarking is a process of embedding hidden information called watermark into different kinds of media objects. It uses basic modulation, multiplexing and transform techniques of communication for hiding information. Traditional techniques used are least significant bit (LSB) modification, discrete cosine transform (DCT), discrete wavelet transform (DWT), discrete Fourier transform (DFT), code division multiple access (CDMA) or a combination of these. Among these, CDMA is the most robust against different attacks except geometric attacks. This paper proposes a blind and highly robust watermarking technique by utilizing the basis of orthogonal frequency division multiplexing (OFDM) and CDMA communication system. In this scheme, the insertion process starts by taking DFT of host images, permuting the watermark bits in randomized manner and recording them in a seed as a key. Then PSK modulation follows inverse DFT (IDFT) that gives watermark information as OFDM symbols. These symbols are spread using spreading codes and then arithmetically added to the host image. Finally, scheme applies inverse DCT (IDCT) to get watermarked host images. The simulation results of the proposed scheme are compared with CDMA-based scheme in DCT domain. The results show that the robustness of the proposed scheme is higher than the existing scheme for non-geometric attacks.

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24

Kuo, Po Yu, and Gan Zhi Fan. "Analysis and Implementation of Rayleigh Fading Channel Using MATLAB." Applied Mechanics and Materials 764-765 (May 2015): 476–80. http://dx.doi.org/10.4028/www.scientific.net/amm.764-765.476.

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Mobile wireless communication is the fastest growing segment of the communication industry. However, it is faced with the challenge of providing reliable high-speed communications due to channel impediments which change over time in unpredictable ways. To analyze the reliability and performance of real communication system, the Rayleigh fading channel is generally applied to simulate the real wireless communication. In this paper, we analyze and implement a flat Rayleigh fading channel based on the inverse discrete Fourier transform (IDFT). The simulation results of level crossing rate (LCR) and average fade duration (AFD) are shown in this paper.

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25

Shen, Wei, and Biyang Wen. "A New Demodulation and Modulation Method Designed for FMCW Radar." Journal of Electrical and Computer Engineering 2010 (2010): 1–6. http://dx.doi.org/10.1155/2010/897429.

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An efficient demodulation method designed for FMCW (Frequency-Modulated Continuous Wave) radar is presented. It is a kind of modified DFT (IDFT) algorithm; the spectrum segment of interest can be easily extracted from the original signal without calculating the whole DFT/FFT. It provides fast demodulation and extraction of desired frequency bands in our HFSWR (High-Frequency Surface Wave Radar) system. The proposed approach enhances the performances of radar system and reduces the computing complexity. The new structure could also be inversely used for signal modulation. And also arbitrary sampling rate conversion could be achieved with the combination of forward and backward structure.

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26

Zheng, Zuo Yong, and Rui Xia Zhang. "A Fast GPU Algorithm for the Inverse of a Circulant Matrix." Applied Mechanics and Materials 121-126 (October 2011): 3755–59. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.3755.

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Circulant matrix is a special case of Toeplitz matrix, which is widely used in many domains of specialization, especially in image and digital signal processing. Calculating the inverse of this category of matrices consists of the following three steps: (1) transform the first row vector to frequency space by using DFT; (2) calculate the inverse of each amplitude in the spectrum; (3) apply IDFT to the adjusted spectrum and reconstruct the inverse of the original circulant matrix. This paper implements such a fast algorithm on the GPU, which is proved around five to ten times faster than is executed on the CPU.

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27

Hwang, Jeng-Kuang, and Yuan-Ping Li. "Efficient Recursive IDFT Scheme for Complex-valued Signals in Tap-selective Maximum-likelihood Channel Estimation." Journal of Signal Processing Systems 60, no. 1 (September 16, 2009): 71–80. http://dx.doi.org/10.1007/s11265-009-0404-x.

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28

Zhang, Meng, and Zhisong Bie. "Research on single carrier frequency domain equalization system based on FQPSK modulation." ITM Web of Conferences 17 (2018): 03012. http://dx.doi.org/10.1051/itmconf/20181703012.

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Feher-patented quadrature phase shift keying (fqpsk) modulation is proposed for single-carrier frequency domain equalization (sc-fde). this paper puts forward a new method modulation called cc-bcd-fqpsk. the fqpsk signal is oversampled to make that the discrete fourier transform (dft)/ inverse dft (idft) processing of it can be applied for sc-fde. the methodology for maintaining waveform continuity with a cyclic prefix (cp) is presented. wrap-around viterbi algorithm (wava) is suggested for demodulation after equalization at the receiver. simulation results show that sc-fde system based on cc-bcd-fqpsk modulation has higher spectral efficiency than linear modulation qpsk and is an effective approach for eliminating isi and using nonlinear high power amplifier.

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29

Li, William Xinzuo, Larry D. Mitchell, Min-Fu Lu, and Michael L. Neumann. "Mapping Nonsquare and Unevenly Spaced 2-D SLDV Data of an Aircraft Fuselage by Using Spatial DFT-IDFT Techniques." Shock and Vibration 3, no. 2 (1996): 135–40. http://dx.doi.org/10.1155/1996/195675.

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The scanning laser Doppler vibrometry (SLDV) technique provides velocities of a structure at 2-dimensional (2-D) angularly evenly spaced (in the laser scanning sense) data points. This causes an unevenly spaced data point distribution on the surface of the test structure. In many cases evenly spaced data point distribution with square or rectangular grids is highly desirable. In this study the SLDV velocity data of a partial surface area of an aircraft fuselage were mapped to truly spatial evenly spaced coordinates by using the spatial DFT-IDFT technique with minimum distortion. This 2-D data mapping technique certainly is not limited to the fuselage, hut can he very useful for many other 3-D structures.

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30

Jung, Seulkee, and Seongsoo Lee. "Design of Unified HEVC 4×4 IDCT/IDST Block." Journal of IKEEE 19, no. 2 (June 30, 2015): 271–75. http://dx.doi.org/10.7471/ikeee.2015.19.2.271.

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31

UEDA, Tetsuhiko, and Kenichi SAITOH. "NUMERICAL SIMULATION FOR RANDOM AEROELASTIC RESPONSES USING INVERSE FOURIER TRANSFORM." Aviation 20, no. 3 (September 29, 2016): 103–9. http://dx.doi.org/10.3846/16487788.2016.1227535.

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This paper reports a new simulation technique for an aeroelastic system which responds to random external forces. Since the aeroelastic system including the effects of unsteady aerodynamics is ordinarily described in the frequency domain, the Inverse Discrete Fourier Transform (IDFT) can be utilized to simulate its random response. The response caused by the external random noise is calculated through a transfer function first in the frequency domain and then converted to the time domain. The objective of the present study is to provide mathematical time history data for evaluating the various estimation methods of the flutter boundary from subcritical responses in flight and/or wind tunnel testing. An example application to the method of flutter prediction is shown. The technique can also be used to evaluate the effects of the active control device coping with atmospheric turbulence.

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32

Lai, Shin-Chi, Sheau-Fang Lei, Chia-Lin Chang, Chen-Chieh Lin, and Ching-Hsing Luo. "Low Computational Complexity, Low Power, and Low Area Design for the Implementation of Recursive DFT and IDFT Algorithms." IEEE Transactions on Circuits and Systems II: Express Briefs 56, no. 12 (December 2009): 921–25. http://dx.doi.org/10.1109/tcsii.2009.2035267.

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33

Sang, Tzu-Hsien, and You-Cheng Xu. "Clipping Noise Compensation with Neural Networks in OFDM Systems." Signals 1, no. 1 (August 3, 2020): 100–109. http://dx.doi.org/10.3390/signals1010005.

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The application of deep learning (DL) to solve physical layer issues has emerged as a prominent topic. In this paper, the mitigation of clipping effects for orthogonal frequency division multiplexing (OFDM) systems with the help of a Neural Network (NN) is investigated. Unlike conventional clipping recovery algorithms, which involve costly iterative procedures, the DL-based method learns to directly reconstruct the clipped part of the signal while the unclipped part is protected. Furthermore, an interpretation of the learned weight matrices of the neural network is presented. It is observed that parts of the network, in effect, implement transformations very similar to the (Inverse) Discrete Fourier Transform (DFT/IDFT) to provide information in both the time and frequency domains. The simulation results show that the proposed method outperforms existing algorithms for recovering clipped OFDM signals in terms of both mean square error (MSE) and Bit Error Rate (BER).

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34

Lai, Shin-Chi, Sheau-Fang Lei, Wen-Ho Juang, and Ching-Hsing Luo. "A Low-Cost, Low-Complexity, and Memory-Free Architecture of Novel Recursive DFT and IDFT Algorithms for DTMF Application." IEEE Transactions on Circuits and Systems II: Express Briefs 57, no. 9 (September 2010): 711–15. http://dx.doi.org/10.1109/tcsii.2010.2056413.

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35

He, Siyuan, Fan Zhang, Weidong Hu, Lei Zhuang, Xingbin Ye, and Guoqiang Zhu. "Investigation of Range Profiles from a Simplified Ship on Rough Sea Surface and Its Multipath Imaging Mechanisms." International Journal of Antennas and Propagation 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/894198.

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The range profiles of a two-dimension (2 D) perfect electric conductor (PEC) ship on a wind-driven rough sea surface are derived by performing an inverse discrete Fourier transform (IDFT) on the wide band backscattered field. The rough sea surface is assuming to be a PEC surface. The back scattered field is computed based on EM numerical simulation when the frequencies are sampled between 100 MHz and 700 MHz. Considering the strong coupling interactions between the ship and sea, the complicated multipath effect to the range profile characteristics is fully analyzed based on the multipath imaging mechanisms. The coupling mechanisms could be explained by means of ray theory prediction and numerical extraction of the coupling currents. The comparison of the range profile locations between ray theory prediction and surface current simulation is implemented and analyzed in this paper. Finally, the influence of different sea states on the radar target signatures has been examined and discussed.

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36

Moshe, S., and D. Hertz. "On computing DFT of real N-point vector and IDFT of DFT-transformed real N-point vector via single DFT." IEEE Signal Processing Letters 6, no. 6 (June 1999): 141. http://dx.doi.org/10.1109/97.763146.

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37

Kim, Hyeung-Yun. "Structural Dynamic System Reconstruction Method for Vibrating Structures." Journal of Dynamic Systems, Measurement, and Control 125, no. 4 (December 1, 2003): 646–53. http://dx.doi.org/10.1115/1.1605992.

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To determine the natural frequencies and damping ratios of composite laminated plates, we present an efficient modal parameter estimation technique by developing a residual spectrum based structural dynamic system reconstruction. The modal parameters can be estimated from poles and residues of the system transfer functions derived from the state space system matrices. However, for modal parameter estimation of multivariable and higher order structural systems over broad frequency bands, this noniterative algorithm gives high accuracy in determining the natural frequencies and damping ratios. It is numerically well-behaved unlike iterative frequency-response-function (FRF) curve-fitting methods. We also discuss necessary conditions for convergence in Hankel norm and the error bounds of the approximated transfer function for the IDFT-based reconstruction system. From vibration tests on cross-ply and angle-ply composite laminates, the natural frequencies and damping ratios can be identified from the eigenvalues of the structural dynamic system matrix derived by the reconstruction method from the experimental frequency response functions. These results are compared with those of finite-element analysis and single-degree-of-freedom curve-fitting.

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38

Gifuni, Angelo, and Stefano Perna. "ANALYSIS ON THE CALCULATION OF THE INVERSE DISCRETE FOURIER TRANSFORM (IDFT) OF PASSBAND FREQUENCY RESPONSE MEASUREMENTS IN TERMS OF LOWPASS EQUIVALENT RESPONSE." Progress In Electromagnetics Research 160 (2017): 63–69. http://dx.doi.org/10.2528/pier17081703.

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39

Wirastuti, N. M. A. E. Dewi, I. G. A. K. Diafari Djuni Hartawan, I. Made Arsa Suyadnya, and Duman Care Khrisne. "Carrier Frequency Offset Effects on OFDM System over Rayleigh Fading Channel." Journal of Electrical, Electronics and Informatics 3, no. 2 (January 9, 2020): 45. http://dx.doi.org/10.24843/jeei.2019.v03.i02.p03.

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Orthogonal Frequency Division Multiplexing (OFDM) system showed the use of Discrete Fourier Transform (DFT) and Inverse Discrete Fourier Transform (IDFT) to perform the baseband modulation and demodulation. So that, it can increase and improve the efficiency of the modulation and demodulation. Currently, the OFDM is being utilized in the field of broadband wireless communication, which transmit signals orthogonally, that increases speed of information transmission. It also has high proficiency with high bandwidth and provide large data rates and robust against the multipath delay spread. On the other hand, there are some issues faced OFDM system which are high Peak Average Power Ratio (PAPR), and sensitive to Phase Noise (PN) and Carrier Frequency Offset (CFO). This paper presents Orthogonal Frequency Division Multiplexing (OFDM) performance evaluation in the presence of CFO with two different environment scenarios were used: an AWGN channel and a Rayleigh fading channel. The simulation was performed to evaluate the effects of CFO based on Bit Error Rate (BER) vs. Energy Bit per Noise Ratio (Eb/No). The results showed that for BER degradation caused by CFO effects have presented in our simulation for both AWGN and Rayleigh fading channel.

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40

Ren, Huiying, Z. Jason Hou, Mark Wigmosta, Ying Liu, and L. Ruby Leung. "Impacts of Spatial Heterogeneity and Temporal Non-Stationarity on Intensity-Duration-Frequency Estimates—A Case Study in a Mountainous California-Nevada Watershed." Water 11, no. 6 (June 21, 2019): 1296. http://dx.doi.org/10.3390/w11061296.

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Changes in extreme precipitation events may require revisions of civil engineering standards to prevent water infrastructures from performing below the designated guidelines. Climate change may invalidate the intensity-duration-frequency (IDF) computation that is based on the assumption of data stationarity. Efforts in evaluating non-stationarity in the annual maxima series are inadequate, mostly due to the lack of long data records and convenient methods for detecting trends in the higher moments. In this study, using downscaled high resolution climate simulations of the historical and future periods under different carbon emission scenarios, we tested two solutions to obtain reliable IDFs under non-stationarity: (1) identify quasi-stationary time windows from the time series of interest to compute the IDF curves using data for the corresponding time windows; (2) introduce a parameter representing the trend in the means of the extreme value distributions. Focusing on a mountainous site, the Walker Watershed, the spatial heterogeneity and variability of IDFs or extremes are evaluated, particularly in terms of the terrain and elevation impacts. We compared observations-based IDFs that use the stationarity assumption with the two approaches that consider non-stationarity. The IDFs directly estimated based on the traditional stationarity assumption may underestimate the 100-year 24-h events by 10% to 60% towards the end of the century at most grids, resulting in significant under-designing of the engineering infrastructure at the study site. Strong spatial heterogeneity and variability in the IDF estimates suggest a preference for using high resolution simulation data for the reliable estimation of exceedance probability over data from sparsely distributed weather stations. Discrepancies among the three IDFs analyses due to non-stationarity are comparable to the spatial variability of the IDFs, underscoring a need to use an ensemble of non-stationary approaches to achieve unbiased and comprehensive IDF estimates.

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41

Ren, Lu, Lusheng Liang, Zhuangzhuang Zhang, Zilong Zhang, Qiu Xiong, Nan Zhao, Yaming Yu, Rosario Scopelliti, and Peng Gao. "The roles of fused-ring organic semiconductor treatment on SnO2 in enhancing perovskite solar cell performance." RSC Advances 11, no. 7 (2021): 3792–800. http://dx.doi.org/10.1039/d1ra00090j.

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A series of n-type FROSs called IDT-T, IDT-I, and IDDT-T were used to passivate the interface between the perovskite layer and SnO₂ layer in PSCs, leading to reduced interfacial loss in hopes of enhancing the performance of PSCs.

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42

Liang, Hong, He Weifeng, He Guanghui, and Mao Zhigang. "Area-efficient HEVC IDCT/IDST architecture for 8K × 4K video decoding." IEICE Electronics Express 13, no. 6 (2016): 20160019. http://dx.doi.org/10.1587/elex.13.20160019.

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43

Huang, Hai, Liyi Xiao, and Jiaming Liu. "CORDIC-Based Unified Architectures for Computation of DCT/IDCT/DST/IDST." Circuits, Systems, and Signal Processing 33, no. 3 (October 3, 2013): 799–814. http://dx.doi.org/10.1007/s00034-013-9661-9.

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44

Popova, Elena K., Sargylana M. Ivanova, Nadezhda V. Savvina, Natalya S. Arkhipova, Ivan O. Popov, Zhanna V. Ascarova, Yani W. Sinambel, Nadezhda V. Avvakumova, and Lyudmila G. Chibyeva. "Assessment of the prevalence of risk factors for chronic non-communicable diseases among employees of the North-Eastern Federal University." Hygiene and sanitation 100, no. 1 (February 12, 2021): 60–65. http://dx.doi.org/10.47470/0016-9900-2021-100-1-60-65.

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Introduction. According to WHO experts, chronic non-communicable disease (NCD) is the leading worldwide medical and social problem. In recent decades, the Republic of Sakha (Yakutia) population showed changes in nutrition habits, physical activity reduction. It increased the spread of modified chronic NCD’s risk factors. Material and methods. The authors performed a one-stage study of modified risk factors and frequency analysis of chronic NCD in the North-Eastern Federal University (NEFU) employees who had medical check-ups in 2017 (n = 800): men (n = 260), women (n = 540). The attendees’ age varied from 30 to 54 years. Abdominal obesity (AO) was diagnosed by two criteria: men’s waist ≥ 90 cm and women’s waist ≥ 80 for Asia residents (IDF1); men’s waist ≥ 94 cm and women’s waist ≥ 80 for European residents (IDF2) (IDF, 2006). Results. This analysis of the study group of NEFU employees showed the median level of SYS and DYS, glucose in serum, and the waist index in both groups, regardless of gender, to be within reference values. The most frequent risk factors of chronic NCD were hypercholesterolemia and abdominal obesity (p = 0.000). A spread of hypercholesterolemia was 16.8%, in men (23.5%) more frequently than in women (13. Every fourth woman and every third man had AO according to IDF criteria compared to attendees without AO (p = 0.000). Conclusion. A significant positive correlation between AO and age, SYS, DYS, cholesterol and glucose in serum was identified.

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Cai, Yunhao, Xiaolong Zhang, Xiaonan Xue, Donghui Wei, Lijun Huo, and Yanming Sun. "High-performance wide-bandgap copolymers based on indacenodithiophene and indacenodithieno[3,2-b]thiophene units." Journal of Materials Chemistry C 5, no. 31 (2017): 7777–83. http://dx.doi.org/10.1039/c7tc01909b.

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Veglia, Jorge E., David L. La Red Martinez, and Reinaldo J. R. Scappini. "Desarrollo Y Simulación De Un Modelo De Transceptor Basado En Prime Para Simulación Sobre Canal PLC." European Scientific Journal, ESJ 14, no. 27 (September 30, 2018): 229. http://dx.doi.org/10.19044/esj.2018.v14n27p229.

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The choice of modification technique for a communications system depends to a large extent on the nature and characteristics of the medium in which it must operate (Hrasnica et al., 2005). In a PLC (Power Line Communications) system, the first applications in the LDR band (oriented to the control of devices) operated with monocarrier modulations, such as ASK, BPSK, and FSK. This allows for low implementation costs, provided that it operates at low data rates and with an error correction system. It is clear that applications require a higher data rate. The modulation technique must overcome challenges such as the necessary equalization for the cause of the non-linearity of the channel, or avoid the propagation delays and the multipath caused by the impedance differences in the branches. Likewise, it must offer flexibility and avoid the use of certain frequencies if they are altered or assigned to another service and, therefore, cannot be used in PLC. In this scenario, one of the techniques that have been imposed in the most used developments in NB-PLC as in BB-PLC has been Orthogonal Frequency Division Multiplexing (OFDM). One of its most attractive aspects from the point of view of its complexity is the possibility of implementing the structure of its multifrequency modulation and demodulation scheme through a simple Inverse Discrete Fourier Transform (IDFT) and its corresponding direct transform, Fast Fourier Transform (FFT). Based on this technique, an appropriate transceiver scheme for operating on a PLC channel model was presented. This development implements the error correction technique proposed for NB-PLC.

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Khandelwal, Mayank, and Vivekanand Khanapuri. "Infrastructure debt fund policy framework in India – issues and challenges." Journal of Financial Management of Property and Construction 20, no. 1 (April 7, 2015): 4–23. http://dx.doi.org/10.1108/jfmpc-02-2014-0003.

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Purpose – This paper aims to identify gaps and critical issues in policy framework for infrastructure debt fund (IDF) to become financially viable in the Indian context. Growth of any economy is dependent on successful implementation of infrastructure projects. However, infrastructure development is linked to availability of equity and debt funds to finance these projects. IDF is an instrument which aims at enabling financing of infrastructure. Design/methodology/approach – The exploratory research adopted is qualitative and based on secondary data related to infrastructure needs, challenges, factors influencing infrastructure financing and options available for infrastructure financing in the Indian context. It investigates the relationship between external factors, internal factors and viability of IDF and provides recommendations to policy makers to roll-out an enabling policy and regulatory environment. Findings – Findings show that issues such as entry barriers for banks, insufficient tax incentives, restrictions on type of projects to be considered for funding and meeting the expectation of low-cost funds need to be addressed so that IDFs can contribute toward funding requirement of the infrastructure sector. Research limitations/implications – IDFs have been recently introduced in India and the use of primary and secondary data has been limited. Comparison of IDF guidelines in India with guidelines for similar instruments in developed countries has been left for a later stage. Originality/value – Value of this study is that it identifies the issues in current guidelines of IDF through the understanding of the policy and regulatory framework that governs IDF. The study also makes recommendations to the government and regulators which would enable IDF to become a viable instrument.

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Jacob, Robert W., Jeffrey M. Trop, and R. Craig Kochel. "Assessing Ground Penetrating Radar's Ability to Image Subsurface Characteristics of Icy Debris Fans in Alaska and New Zealand." Journal of Environmental and Engineering Geophysics 23, no. 4 (December 2018): 423–36. http://dx.doi.org/10.2113/jeeg23.4.423.

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Icy debris fans have recently been described as fan shaped depositional landforms associated with (or formed during) deglaciation, however, the subsurface characteristics remain essentially undocumented. We used ground penetrating radar (GPR) to non-invasively investigate the subsurface characteristics of icy debris fans (IDFs) at McCarthy Glacier, Alaska, USA and at La Perouse Glacier, South Island of New Zealand. IDFs are largely unexplored paraglacial landforms in deglaciating alpine regions at the mouths of bedrock catchments between valley glaciers and icecaps. IDFs receive deposits of mainly ice and minor lithic material through different mass-flow processes, chiefly ice avalanche and to a lesser extent debris flow, slushflow, and rockfall. We report here on the GPR signal velocity observed from 15 different wide-angle reflection/refraction (WARR) soundings on the IDFs and on the McCarthy Glacier; the effect of GPR antenna orientation relative to subsurface reflections; the effect of spreading direction of the WARR soundings relative to topographic contour; observed differences between transverse electric (TE) and transverse magnetic (TM) antenna polarization; and a GPR profile extending from the McCarthy Glacier onto an IDF. Evaluation of the WARR soundings indicates that the IDF deposits have a GPR signal velocity that is similar to the underlying glacier, and that the antenna polarization and orientation did not prevent identification of GPR reflections. The GPR profile on the McCarthy Glacier indicates that the shallowest material is layered, decreases in thickness down fan, and has evidence of brittle failure planes (crevasses). The GPR profile and WARR soundings collected in 2013 indicate that the thickness of the McCarthy Glacier is 82 m in the approximate middle of the cirque and that the IDF deposits transition with depth into flowing glacial ice.

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Kidambi, Sunder S. "Simultaneous computation of the DFT of an N-point real sequence and the IDFT of an N-point complex sequence with conjugate symmetry with a single N-point DFT." Signal Processing 81, no. 5 (May 2001): 1109–12. http://dx.doi.org/10.1016/s0165-1684(01)00020-2.

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Weschenfelder, Adriana Burin, Eliana Veleda Klering, Rita de Cássia Marques Alves, and Éber José de Andrade Pinto. "Geração de Curvas IDFs para Cenários Projetados na Cidade de Porto Alegre/RS." Revista Brasileira de Meteorologia 34, no. 2 (June 2019): 201–16. http://dx.doi.org/10.1590/0102-77863340026.

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Resumo O aumento na frequência de eventos extremos associados às alterações climáticas podem modificar as curvas IDFs existentes. A metodologia para definição de curvas IDF considerando cenários futuros consistiu em calibrar o modelo estocástico para gerar séries sintéticas diárias de precipitação com base em dados observados do município de Porto Alegre e gerar séries sintéticas perturbadas a partir de seis MCGs, três cenários A1B, A2 e B1 para os períodos de 2046 a 2065 e 2080 a 2099. Na elaboração das IDFs foram desagregados os dados sintéticos diários, tanto para a linha de base (1974 a 2014), quanto para os cenários projetados, utilizando as relações de desagregação da IDF atual de Porto Alegre. Os resultados obtidos após a calibração indicaram ser o modelo estocástico utilizado eficiente na representação dos dados local. Os resultados encontrados para as projeções no primeiro período indicam que as simulações dos modelos são razoavelmente aplicáveis, sugerindo a utilização da curva IDF atual com uma majoração de 10 a 20% no dimensionamento de obras hidráulicas. Já para o segundo período de projeção em função da grande variabilidade nos resultados encontrados para os diferentes modelos não há confiança na aplicabilidade destas projeções.

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