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Data delivery delay and cross-layer packet size analysis for reliable transmission of Licklider transmission protocol in space networks

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Science China(Information Sciences) 2024年第9期67卷 229-244页

作者： Guannan YANG Ruhai WANG Kanglian ZHAO Wenfeng LI Dong YAN School of Information Engineering Nanjing University of Finance and Economics Drayer Department of Electrical and Computer Engineering Lamar University School of Electronic Science and Engineering Nanjing University Beijing Aircraft Overall Design Department

Delay/disruption tolerant networking(DTN) is proposed as a networking architecture to overcome challenging space communication characteristics for reliable data transmission service in presence of long propagation delays and/or lengthy link disruptions. Bundle protocol(BP) and Licklider Transmission Protocol(LTP) are the main key technologies for DTN. LTP red transmission offers a reliable transmission mechanism for space networks. One of the key metrics used to measure the performance of LTP in space applications is the end-to-end data delivery delay, which is influenced by factors such as the quality of spatial channels and the size of cross-layer packets. In this paper, an end-to-end reliable data delivery delay model of LTP red transmission is proposed using a roulette wheel algorithm, and the roulette wheel algorithm is more in line with the typical random characteristics in space networks. The proposed models are validated through real data transmission experiments on a semi-physical testing platform. Furthermore, the impact of cross-layer packet size on the performance of LTP reliable transmission is analyzed, with a focus on bundle size, block size, and segment size. The analysis and study results presented in this paper offer valuable contributions towards enhancing the reliability of LTP transmission in space communication scenarios.

关键词： Licklider transmission protocol DTN bundle protocol cross-layer packets size space communication

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Fault-tolerant capability analysis of six-phase induction motor with distributed, concentrated, and pseudo-concentrated windings

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Scientia Iranica 2024年第10期31卷 775-789页

作者： Alemi-Rostami, Mehdi Rezazadeh, Ghasem Tahami, Farzad Akbari-Resketi, Hamid Reza Ministry of Science Research and Technology Tehran Iran School of Electrical and Computer Engineering College of Engineering University of Tehran Tehran Iran Department of Electrical Engineering Sharif University of Technology Tehran Iran Department of Electrical and Computer Engineering Babol Noshirvani University of Technology Babol Iran

Six-phase motors are becoming more popular because of their advantages such as lower torque ripple, better power distribution per phase, higher efficiency, and fault-tolerant capability compared to the three-phase ones. This paper presents the fault-tolerant capability analysis of a symmetrical six-phase induction motor equipped with distributed, conventional concentrated, and pseudo-concentrated windings under open-circuit fault scenarios. For further investigation, different load types such as constant-speed, constant-torque, and constant-power are applied to the motor. Two concepts of magnetic and physical phase separations are introduced as factors affecting the motor reliability. Analytically, these factors give an insight into how the pseudo-concentrated winding could be a fault-tolerant alternative. Moreover, five parameters such as the change of output power, power loss, power factor, efficiency, and expected load loss are considered as the fault-tolerant capability parameters to evaluate the windings reliability. The aforementioned parameters are reported using the finite element analysis for different fault scenarios and different load types. Although the baseline motor dimensions are not optimized for applying the pseudo-concentrated winding, the pseudo-concentrated shows a promising performance with high fault-tolerant capability. © 2024 Sharif University of Technology. All rights reserved.

关键词： Reliability analysis

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Negative Group Delay Prototype Filter Based on the Ratio of Two Classical Chebyshev Filter Transfer Functions

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Progress In Electromagnetics Research B 2024年 107卷 139-153页

作者： Kandic, Miodrag Bridges, Greg E. Department of Electrical and Computer Engineering University of Manitoba WinnipegMB Canada

A Negative Group Delay (NGD) prototype filter design, based on the ratio of two Chebyshev filter transfer functions, is presented. The two transfer functions are of the same order, but with different in-band ripple amplitudes and different 3 dB-bandwidths. The overall transfer function exhibits both an in-band ripple and an out-of-band steep-slope magnitude transition characteristic of a Chebyshev filter, while also exhibiting an in-band NGD. For high-order designs and in the upper asymptotic limit, the NGD-bandwidth product of the filter is shown to be a linear function of out-of-band gain in decibels. A resonator-based methodology is used to show how frequency upshifted filter designs can be implemented in a Sallen-Key topology or in an all-passive ladder topology. An in-band combined magnitude/phase distortion metric is evaluated for examples of the NGD filter. It is shown that the distortion metric is proportional to the design order, the in-band ripple amplitude, and the out-of-band gain. For a prescribed distortion metric value, it is demonstrated that the proposed design can achieve a higher NGD-bandwidth product than an equivalent Butterworth design, which has a flat in-band magnitude characteristic. Additionally, input waveforms with bandwidths extending to the entire frequency range where the group delay is negative (typically larger than the 3 dB-bandwidth) should not be applied to this filter design as it results in strong levels of distortion. © (2024), (Electromagnetics Academy). All rights reserved.

关键词： Chebyshev filters

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Derandomizing Codes for the Adversarial Wiretap Channel of Type II

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IEEE Transactions on Information Theory 2025年第6期71卷 4686-4707页

作者： Ruzomberka, Eric Nikbakht, Homa Brinton, Christopher G. Love, David J. Vincent Poor, H. Air Force Institute of Technology Department of Electrical and Computer Engineering DaytonOH45433 United States Princeton University Department of Electrical and Computer Engineering PrincetonNJ08540 United States Purdue University Elmore Family School of Electrical and Computer Engineering West LafayetteIN47907 United States

The adversarial wiretap channel of type II (AWTC-II) is a communication channel that can a) read a fraction of the transmitted symbols up to a given bound and b) induce both errors and erasures in a fraction of the symbols up to given bounds. The channel is controlled by an adversary who can freely choose the locations of the symbol reads, errors and erasures via a process with unbounded computational power. The AWTC-II is an extension of Ozarow’s and Wyner’s wiretap channel of type II to the adversarial channel setting. The semantic-secrecy (SS) capacity of the AWTC-II is partially known, where the best-known lower bound is non-constructive and proven via a random coding argument that uses a large number (that is, exponential in blocklength n) of random bits to describe the random code. In this work, we establish a new derandomization result in which we match the best-known lower bound via a non-constructive random code that uses only O(n2) random bits. Unlike fully random codes, our derandomized code admits an efficient encoding algorithm and benefits from some linear structure. Our derandomization result is a novel application of random pseudolinear codes – a class of non-linear codes first proposed for applications outside the AWTC-II setting, which have k-wise independent codewords where k is a design parameter. As the key technical tool in our analysis, we provide a novel concentration inequality for sums of random variables with limited independence, as well as a soft-covering lemma similar to that of Goldfeld, Cuff and Permuter that holds for random codes with k-wise independent codewords. © 1963-2012 IEEE.

关键词： Signal encoding

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VoWi-Fi security threats: Address resolution protocol attack and countermeasures

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IET Networks 2024年第2期13卷 129-146页

作者： Lu, Kuan-Chu Liu, I.-Hsien Chang, Keng-Hao Li, Jung-Shian Department of Electrical Engineering Institute of Computer and Communication Engineering National Cheng Kung University Tainan Taiwan

B5G/6G networks are facing challenges in the deployment of additional base stations. However, Taiwan's four major operators have launched VoWi-Fi calling services to maintain signal quality and coverage for customers. These services pose potential threats when users connect to untrusted Wi-Fi networks. Therefore, the authors utilised commercial equipment to study the security of VoWi-Fi calling services offered by Taiwan's four major telecom companies. The authors employed address resolution protocol attack methods to develop two verification attacks that bypass existing security measures: one for dropping session initiation protocol packets and the other for dropping voice call packets, both capable of circumventing current security defences. Through real-world experiments, the authors confirmed their feasibility and assessed their potential harm. Consequently, two defence methods are proposed. The first is an anti-attack algorithm for app and device manufacturers to detect the security of the user's calling environment. The second is a recommendation for telecom operators to implement new detection mechanisms to safeguard user rights. The cover image is based on the Case Study VoWi-Fi security threats: Address resolution protocol attack and countermeasures by Kuan-Chu Lu et al., https://***/10.1049/ntw2.12113. © 2024 The Authors. IET Networks published by John Wiley & Sons Ltd on behalf of The Institution of engineering and Technology.

关键词： Wi-Fi

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Highly-efficient(>70%)and Wide-spectral(400-1700 nm)sub-micron-thick InGaAs photodiodes for future high-resolution image sensors

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Light(Science & Applications) 2024年第12期13卷 3224-3235页

作者： Dae-Myeong Geum Jinha Lim Junho Jang Seungyeop Ahn SeongKwang Kim Joonsup Shim Bong Ho Kim Juhyuk Park Woo Jin Baek Jaeyong Jeong SangHyeon Kim School of Electrical Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea Department of Electrical and Computer Engineering Inha UniversityIncheon 22212Republic of Korea

This paper demonstrates the novel approach of sub-micron-thick InGaAs broadband photodetectors(PDs)designed for high-resolution imaging from the visible to short-wavelength infrared(SWIR)*** approaches encounter challenges such as low resolution and crosstalk issues caused by a thick absorption layer(AL).Therefore,we propose a guided-mode resonance(GMR)structure to enhance the quantum efficiency(QE)of the InGaAs PDs in the SWIR region with only sub-micron-thick *** TiOx/Au-based GMR structure compensates for the reduced AL thickness,achieving a remarkably high QE(>70%)from 400 to 1700 nm with only a 0.98μm AL InGaAs PD(defined as 1μm AL PD).This represents a reduction in thickness by at least 2.5 times compared to previous results while maintaining a high ***,the rapid transit time is highly expected to result in decreased electrical *** effectiveness of the GMR structure is evident in its ability to sustain QE even with a reduced AL thickness,simultaneously enhancing the transit *** breakthrough offers a viable solution for high-resolution and low-noise broadband image sensors.

关键词： thick resolution image

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Enhanced Far-Field Localization Scheme Using Multi-RIS and Efficient Beam Sweeping

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Progress In Electromagnetics Research C 2024年 140卷 163-175页

作者： Alhafid, Abdulrahaman Kh. Younis, Sedki Ali, Y. E. Mohammed Electrical Engineering Department College of Engineering University of Mosul Mosul Iraq Computer and Information Engineering Department College of Electronics Engineering Ninevah University Mosul Iraq Computer and Communications Engineering Department College of Engineering Nawroz University KRG Duhok Iraq

Future 6G networks are anticipated to use reconfigurable intelligent surfaces (RISs) because of their capability to expand coverage, provide a customizable wireless environment, increase localization accuracy, etc. In this paper, RIS-aided localization is considered with orthogonal frequency division multiplexing (OFDM) and single-input single-output (SISO) downlink system in millimeter-wave (mmWave). An efficient beam sweeping (EBS) scheme is proposed accomplished by an RIS to scan the area of interest and estimate the direction of the user equipment (UE), i.e., the signal’s angle of departure (AoD). The AoD with the measured signal time of arrival (ToA), from the RIS to the UE, is used to estimate the UE position. The ToA measurements can be obtained by exploiting the OFDM signal, while the beam sweeping can be obtained by carefully designing the RIS phase profile. The first step of the proposed EBS scheme is to scan the whole area of interest with equally spaced beam angles for coarse estimation of AoD. Then, based on this estimation, the RIS is reconfigured to sweep a slight angle’s range by narrow beams to refine the AoD estimation. Besides, a multi-RIS scenario is proposed, and leveraging the EBS and the consensus fusion method is used to obtain accurate position estimation. Simulation results demonstrate that the proposed EBS in single and multi-RIS scenarios enhances positioning accuracy compared to linear beam sweeping (LBS) methods. Also, the impact of increasing the number of RIS elements and number of sweeping beams, as well as the number of RISs, is investigated thoroughly via numerical simulations. Furthermore, the achievable localization accuracy is assessed using the positioning error bound (PEB). © 2024, Electromagnetics Academy. All rights reserved.

关键词： Millimeter waves

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The consequences of eye tracking on brain and heart coherence

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Multimedia Tools and Applications 2024年第38期83卷 86025-86035页

作者： Attar, Eyad Talal Department of Electrical and Computer Engineering Faculty of Engineering King Abdulaziz University Jeddah21589 Saudi Arabia

When the eye uses the brain and heart, the cardiovascular and nervous systems integrate and interact. Because changes in retinal microcirculation are independent predictors of cardiovascular events, the eye serves as a "display" to the cardiovascular system and brain. The eye, which has two circulatory systems and a rich vascular supply, is a prime candidate for this study and benefits from early damage to the target organ. Eye movements performed during the visual search pose a challenge in identifying critical points in the eye scene. Because it uses different brain pathways and relates to the cardiac cycle, humans’ ability to spot anomalies under challenging circumstances means they are always needed for visual search. ECG (electrocardiogram), electroencephalogram (EEG), and eye tracking can improve visual search training and attention-tracking performance. EEG data can also be analyzed in real time using eye-tracking technology. Previous work has discussed the EEG or ECG concerning attraction during visual search. The eyeball’s movement combined with the ECG in the previous investigation and introduced large electroencephalographic (EEG) artifacts. This assessment aims to (a) identify brain–heart coherent features influenced by the visual search task and (b) discover the behavior of EEG frequency bands and heart rate variability (HRV) features. EEG and ECG were used to analyze and predict inattention in individuals during a visual search task. The EEG determines human brain function and considers to detect the variability in the EEG frequency band. The work proposed a visual search task with EEG and ECG analysis. Five participants recorded EEG and ECG recordings in three different scenarios: rest, gaze tracking, and normal. Statistical evaluation was used to compare EEG and ECG characteristics and Pearson’s correlation was employed for statistical analysis. Statistical ANOVA analysis revealed statistically significant (p > 0.05) differences between theta (F3) an

关键词： Electrocardiograms

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A transformer model for boundary detection in continuous sign language

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Multimedia Tools and Applications 2024年第42期83卷 89931-89948页

作者： Rastgoo, Razieh Kiani, Kourosh Escalera, Sergio Electrical and Computer Engineering Faculty Semnan University Semnan*** Iran Sergio Escalera Department of Mathematics and Informatics Universität de Barcelona and Computer Vision Center Barcelona Spain

Sign Language Recognition (SLR) has garnered significant attention from researchers in recent years, particularly the intricate domain of Continuous Sign Language Recognition (CSLR), which presents heightened complexity compared to Isolated Sign Language Recognition (ISLR). One of the prominent challenges in CSLR pertains to accurately detecting the boundaries of isolated signs within a continuous video stream. Additionally, the reliance on handcrafted features in existing models poses a challenge to achieving optimal accuracy. To surmount these challenges, we propose a novel approach utilizing a Transformer-based model. Unlike traditional models, our approach focuses on enhancing accuracy while eliminating the need for handcrafted features. The Transformer model is employed for both ISLR and CSLR. The training process involves using isolated sign videos, where hand keypoint features extracted from the input video are enriched using the Transformer model. Subsequently, these enriched features are forwarded to the final classification layer. The trained model, coupled with a post-processing method, is then applied to detect isolated sign boundaries within continuous sign videos. The evaluation of our model is conducted on two distinct datasets, including both continuous signs and their corresponding isolated signs, demonstrates promising results. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.

关键词： Gesture recognition

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A Novel Deep Learning Approach Toward Efficient and Accurate Recommendation Using Improved Alternating Least Squares in Social Media

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Journal of The Institution of Engineers (India): Series B 2024年第3期105卷 657-675页

作者： Dhawan, Sanjeev Singh, Kulvinder Batra, Amit Choi, Anthony Choi, Ethan Department of Computer Science and Engineering University Institute of Engineering and Technology Kurukshetra University Haryana India Department of Electrical and Computer Engineering Mercer University MaconGA United States

The increasing number of electronic transactions on the Internet has given rise to the design of recommendation systems. The main objective of these systems is to give recommendations to the users about the items (i.e., movies, music, books, etc.) they are likely to purchase in near future. These recommendations are on the foundation of the response provided by the other individuals about these products in the terms of ratings, which are in the form of a five-star rating system. Plenty of algorithms have been proposed in the past for building recommender systems. The most popular of these algorithms comprise content-centered and collaborative filtering recommendation methodologies. Recently, matrix factorization has appeared as a technique in recommender systems. Several algorithms centered on matrix factorization have been suggested in the recent past. In this paper, an improved alternating least squares algorithm has been proposed for building more efficient and accurate recommender systems which improves the performance of matrix factorization. The performance of the model has been evaluated using metrics like root-mean-square-error and execution time. However, in general, the time complexity of both algorithms is O(n^3), where n is the number of users or items. This is because both IALS and ALS involve iteratively solving a system of linear equations, and the time complexity of solving a system of linear equations is O(n^3). However, IALS can achieve significant performance improvements over ALS, particularly for large datasets, due to its incorporation of stochastic gradient descent and parallelization techniques. © The Institution of Engineers (India) 2024.

关键词： Recommender systems

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