bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Floquet engineering approach to optimize Schottky junction-based surface plasmonic waveguides
Authors: Herath Kosala , Gunapala Sarath D. , Premaratne Malin 
Published: July 2023

AbstractThe ability to finely control the surface plasmon polariton (SPP) modes of plasmonic waveguides unveils many potential applications in nanophotonics. This work presents a comprehensive theoretical framework for predicting the propagation characteristics of SPP modes at a Schottky junction exposed to a dressing electromagnetic field. Applying the general linear response theory towards a periodically driven many-body quantum system, we obtain an explicit expression for the dielectric function of the dressed metal. Our study demonstrates that the dressing field can be used to alter and fine-tune the electron damping factor. By doing so, the SPP propagation length could be controlled and enhanced by appropriately selecting the intensity, frequency and polarization type of the external dressing field. Consequently, the developed theory reveals an unexplored mechanism for enhancing the SPP propagation length without altering other SPP characteristics. The proposed improvements are compatible with existing SPP-based waveguiding technologies and could lead to breakthroughs in the design and fabrication of state-of-the-art nanoscale integrated circuits and devices in the near future.
Delayed feedback control for chaotic vibration in nonlinear impact dynamics of bouncing agricultural tractor
Authors: Watanabe Masahisa , Sakai Kenshi 
Published: July 2023

AbstractAgricultural tractors often lose contact and recollide with the ground surface while driving on narrow paddy fields and bumpy farm roads owing to excessive vibrations. These nonlinear impact dynamics can cause chaotic vibrations during tractor operation. Chaotic vibrations are random complex motions that can deteriorate tractor stability and lead to tractor overturning accidents, causing damage to machinery and risk of injury to the operator. This study investigates the theoretical feasibility of chaos control to eliminate chaotic vibrations in tractor dynamics. Delayed feedback (DF) control is employed to eliminate complex vibrations in tractor dynamics. First, the frequency response, bifurcation diagram, and largest Lyapunov exponent are obtained to investigate the nonlinear dynamics of the tractor and identify the parametric region in which chaotic vibrations occur. Subsequently, the DF control is designed based on the trial-and-error method and applied to the tractor dynamics as the driving force control input. The numerical results demonstrate that the DF control can successfully eliminate chaotic vibration and reduce the vibration level. Therefore, this study is expected to contribute to improving the tractor safety by reducing the risk of overturning.
Users' grouping algorithm for fairness improvement of NOMA‐based multi‐beams satellite networks intended for 5G
Authors: Biyoghe Joel , Balyan Vipin 
Published: July 2023

AbstractNon‐Orthogonal Multiple‐Access (NOMA)‐based Multibeam Satellite Networks (MBSNs) are intended for 5G implementation, and 5G networks set the requirement for both high system capacity as well as high system reliability to all users, which is achieved via high system's fairness. The NOMA network requires a user grouping algorithm (UGA), and most existing UGAs for 2‐users NOMA‐MBSNs, favor the system's capacity maximization with little regard to the system's fairness. Thus, this paper proposes a UGA that maximizes the fairness of 2‐users NOMA‐MBSNs. The algorithm seeks to group 2M users into M‐pairs satisfying three requirements, (i) a minimum channel‐gain margin; (ii) high channel‐correlation coefficients; and (iii) there is high fairness amongst the resulting pairs, in term of their respective channel‐correlation coefficients, to increase the users' fairness of the system. To achieve this, the 2M users are split into two sets of M‐far and M‐near users based on users' channel gains for pairing far and near users with high channel‐correlation coefficients. It will turn it into a maximization Bipartite Matching problem (BPMP) of channel‐correlation coefficients. The BPMP is addressed by means of the Hungarian Method (HM) to ensure high fairness amongst resulting pairs regarding their channel‐correlation coefficients. The proposed UGA demonstrates superior fairness compared to existing UGAs.
Integrated sensing and communication‐promoted beam tracking and coverage for complex vehicular networks
Authors: Zhao Yifeng , Huang Xuan , Chen Ning , Liu Haoran , Huang Lianfen 
Published: July 2023

AbstractThe future vehicle‐to‐everything (V2X) scenarios greatly call for reliable and efficient communication links between roadside units (RSUs) and vehicles. Integrated sensing and communication (ISAC) represents one of the key candidate technologies for 6G, which provides new solutions for this problem. In this paper, the beam tracking design for V2X communication is investigated by exploiting the ISAC technique, where the RSU uses the echoes of the ISAC signals to estimate the motion parameters of the vehicles. Compared with traditional feedback‐based beam tracking, the proposed method can reduce the overall signaling costs and improve communication robustness. Furthermore, to achieve high accuracy and low latency for beam alignment, a Trajectory Adaptive Unscented Kalman Filter (TA‐UKF) beam tracking algorithm is proposed, which obtains the optimal state transition model following the change of the vehicle state. Considering practical application scenarios, an ISAC‐based adaptive beam coverage (ISAC‐AC) scheme is further developed for the beam tracking of extended targets, which can achieve the beam misalignment of vehicles in practical scenarios. Numerical results demonstrate that the proposed beam tracking and coverage strategies outperform baseline approaches.
Polarization dynamics in spin‐VCSELs with integrated surface grating for high birefringence splitting
Authors: Lindemann Markus , Jung Natalie , Manrique‐Nieto Nicolas , Pusch Tobias , Michalzik Rainer , Gerhardt Nils C. , Hofmann Martin R. 
Published: July 2023

AbstractPolarization dynamics in spin‐polarized vertical‐cavity surface‐emitting lasers (spin‐VCSELs) with high birefringence have recently been demonstrated to offer very high potential for optical data‐transmission systems that outperform their counterparts based on conventional direct current modulation by far. For polarization dynamics in spin‐VCSELs, the birefringence determines the resonance frequency and thus the modulation bandwidth. In previous work, birefringence was controlled using mechanical strain, which lacks the ability to be integrated in standard VCSEL manufacturing processes. In this work the polarization dynamics of a VCSEL with an integrated birefringence control mechanism is demonstrated based on custom designed integrated surface gratings. It is found that, despite the surface grating which is commonly known to stabilize the polarization, the presented spin‐VCSELs are able to generate polarization oscillations with frequencies corresponding to the birefringence induced by the surface grating and show polarization dynamics up to 68 GHz.
The design of non‐stacked and symmetric XOR for high‐speed applications
Authors: Park Minsu , Jin Jahoon , Park Sehoon , Chun jung‐Hoon 
Published: July 2023

AbstractThe paper proposes an advanced exclusive‐OR (XOR) design using a non‐stacked symmetric structure based on complementary pass transistor logic (CPL) for high‐speed applications. The proposed XOR adopts a non‐stacked structure where a cascade structure is used for pull‐up/down paths instead of a cascoded structure, allowing the increase of pull‐up/down strength and thus faster output transitions. The CPL provides a symmetric scheme that further improves the bandwidth by eliminating the deterministic jitter generated from various input patterns. Verified in a 28‐nm CMOS process, the proposed XOR shows 17.2 times smaller data‐dependent jitter compared to the conventional XOR at the data rate near the limit bandwidth of the process.
Attention‐based model for dynamic IR drop prediction with multi‐view features
Authors: Zhu Wenhao , Liu Wu 
Published: July 2023

AbstractDynamic IR drop prediction based on machine learning has been studied in recent years. However, most proposed models used all input features extracted from circuits or manually selected parts of raw features as inputs, which failed to differentiate the order of priority among input features in a flexible manner. In this paper, QuantumForest to vector‐based dynamic IR drop prediction is introduced. With the sparse attention mechanism brought by QuantumForest, important attributes of circuits are weighed more heavily than others. A new multi‐view feature creation method is also proposed and a novel regional distance feature is built up subsequently. The performance is evaluated on two chip designs with real simulation vectors. The experiment results indicate that the prediction result of the method outperforms other prominent methods for dealing with machine learning based IR drop analysis, reaching an average MAE of only 1.457 on two designs.
Influence of reference path length on self‐heterodyne‐based Brillouin observation
Authors: Sakamoto Mana , Sasage Haruki , Nakamura Kentaro , Mizuno Yosuke , Lee Heeyoung 
Published: July 2023

AbstractFibre‐optic distributed Brillouin sensing that utilises correlation‐domain techniques often requires an optical delay fibre in the reference path to control the correlation peak order in the sensing fibre. Nonetheless, a suboptimal delay fibre length can result in decreased performance. In this work, as a first step towards clarifying the optimal delay fibre length for Brillouin correlation‐domain sensing, the authors evaluate the effect of changing the delay fibre length on the Brillouin gain spectra in a full‐length measurement scenario.
An omega‐k algorithm for multireceiver synthetic aperture sonar
Authors: Zhang Xuebo , Yang Peixuan , Sun Haixin 
Published: July 2023

AbstractIn this Letter, the authors present a novel imaging algorithm for multireceiver synthetic aperture sonar (SAS). The Loffeld's bistatic formula (LBF) including quasi‐monostatic (QM) and multireceiver deformation (MD) phases is first reformulated into range‐variant and range‐invariant phases. After compensating the range‐invariant phase, the subsequent steps are the extended Stolt mapping for each bistatic SAS. Based on simulations, the presented method can also provide high‐resolution result which is similar to that of back projection (BP) algorithm.
Conversion‐less algebraic interleaver architecture for low‐latency IDMA systems
Authors: Kong Byeong Yong 
Published: July 2023

AbstractThis letter presents a conversion‐less algebraic interleaver architecture for low‐latency interleave division multiple access (IDMA) systems. The existing architectures adopt the two‐step approach that first generates a set of sequential indices, and then converts it into a set of interleaved indices, elongating the latency. In contrast, the proposed structure directly produces the interleaved indices by employing a logic that keeps returning the next index corresponding to the current one. As a result, it can greatly alleviate the latency compared with the existing schemes in the literature.
A 0.9 V wideband SPLL with an adaptive fast‐locking circuit achieving 24.68 µs settling time reduction
Authors: Wang Binghui , Shu Zhou , Yang Haigang 
Published: July 2023

AbstractA low‐power wideband self‐biased phase‐locked loop (SPLL) is proposed for multi‐protocol SerDes applications in this letter. With the proposed adaptive fast‐locking current circuit (AFLCC) and self‐biased charge pump (CP), the settling time is reduced significantly, and no extra power and jitter contribution. In addition, a start‐up module is adopted to reset the system to an optimal initial operating frequency quickly. The proposed 1‐3‐GHz SPLL, fabricated in TSMC 28‐nm CMOS process, occupies a compact 0.028 mm2 area. It achieves a roughly constant settling time of 5 μs over all frequencies and division ratios range. Only 0.96 mW is consumed at 1 GHz frequency.
Fixed frequency beam‐steering using bow‐tie slot based dielectric filled waveguide antenna array
Authors: Bansal Aakash , Panagamuwa Chinthana J. , Whittow William G. 
Published: July 2023

AbstractThe paper presents a new practical design for a 4 × 1 planar switched array of dielectric filled waveguide antennas loaded with bow‐tie shaped slots operating at 26.5 to 29.5 GHz for 5G millimetre‐wave applications. The design is realized as a three‐layered architecture, with the top layer behaving as a radiator, the bottom layer as a feed network and a control circuit; and a common ground plane in the middle layer, offering a small form factor. The bow‐tie slots are used to achieve suitable bandwidth with a stable gain of ∼ 13 dBi. The proposed dielectric filled waveguide (DFW) is shown to offer a 5 deg/GHz freq.‐controlled beam‐sweep and a 70° fixed freq. beam‐steer. With only three switching ICs, it offers low power consumption and fast beam‐steering. Further, a combination of freq.‐controlled beam‐scanning and fixed‐freq. beam‐steering allows for a wide coverage of the antenna.
Tensor‐based mobile channel tracking for IRS‐aided transmission systems
Authors: Su Ying , Zhang Jing 
Published: July 2023

AbstractIn communication and sensing integrations, an intelligent reflective surface (IRS) will provide an auxiliary wireless link to enhance coverage and information transmission quality. For IRS‐aided millimetre wave multi‐input multi‐output systems, the instantaneous cascaded channel is highly dimensional, resulting in the difficulty of acquiring channel state information. This letter proposed a tensor‐based Kalman filtering method. Under a parallel factor decomposition condition, a distributed sub‐filter algorithm is established. This method benefits from low‐dimensional tensor modes and known IRS phase shifts. It can track the channel with a few pilot overheads.
Claw‐pole magnetic levitation torque motor for 2D valve with automatic neutral adjustment
Authors: Huang Jiahui , Song Zhankai , Li Sheng , Ruan Jian 
Published: July 2023

AbstractIn order to solve the problems of complex structure and the difficulty of neutral adjustment of the existing 2D valve electro‐mechanical converter, a kind of claw pole magnetic levitation torque motor (CPMLTM) was proposed, which automatically suspended the rotor in an axially and circumferentially neutral position by using the cogging torque and axial recovery forces between the stator claw pole and the rotor permanent magnet (PM). Compared with the conventional moving iron torque motor, it has positive magnetic stiffness, 1.54 times higher PM utilisation and 33.6% lower mass. A qualitative mathematical model of output torque is derived based on equivalent magnetic circuit model. Then, the response surface method was used to build the second‐order response surface model, and NSGA‐2 was used to optimise the design of five key structural parameters, and the non‐inferior solution sets satisfying the maximisation of the cogging torque, output torque and axial recovery force were obtained. The experimental prototype was developed, and static experiments were carried out on the experimental rigs. The results show that the relationship between the input current and the output angular displacement of the CPMLTM is linearly proportional when the magnetomotive force generated by the coil winding is from −50 to 50 A.
Nonlinear state estimator design and implementation for speed control of a BLDC motor drive using square‐root extended H∞$\text{H}_{\infty}$ filter
Authors: Chandra Kumar Pakki Bharani , Potnuru Devendra , Durairaj Danalakshmi , Manoharan Premkumar , Alhelou Hassan Haes 
Published: July 2023

AbstractSensorless speed control of a brushless DC (BLDC) motor, basically a combined control‐observer design, plays a crucial role in several industries, including electrical and aerospace applications. The key idea is to use only electrical (current) sensors and the remaining mechanical states (speed and rotor position) to be estimated using square‐root extended filter (SREF) for a BLDC motor. These estimated states are then fed‐back to the controller. In most of the designs, it is assumed that the BLDC motor plant parameters are constant; however, in reality, their parameters vary due to various intrinsic and extrinsic conditions. Compared to the conventional extended Kalman filter or its square‐root version, the proposed SREF for the BLDC motor has an inherent tendency to deal with parameter uncertainties and hence improves the robustness of the overall system. The robustness of the proposed scheme is tested at various reference speeds for a closed‐loop BLDC drive; further parametric uncertainties in stator resistance, detuning of inductance, and change in load are considered. The proposed control‐observer strategy using SREF is compared with its counterpart square‐root extended Kalman filter (SREKF), and the experimental results validate the efficacy of SREF for speed control of BLDC motor drive during the nominal conditions and in the presence of parametric uncertainties.
A reliable optimization framework for parameter identification of single‐diode solar photovoltaic model using weighted velocity‐guided grey wolf optimization algorithm and Lambert‐W function
Authors: Premkumar Manoharan , Shankar Natarajan , Sowmya Ravichandran , Jangir Pradeep , Kumar Chandrasekaran , Abualigah Laith , Derebew Bizuwork 
Published: July 2023

AbstractIn estimating the parameters of the five unknown parameters Single‐Diode Model (SDM) of the solar photovoltaic (PV) model, a non‐linear equation for the PV cell current is typically utilized. Then, the error between the estimated current and measured current is computed using the objective function called Root‐Mean‐Square‐Error (RMSE). In order to compute the PV cell current in SDM, an iterative method built on the Lambert‐W function is presented in this study. Along with the Lamber‐W function, an optimization algorithm called Weighted Velocity‐Guided Grey Wolf Optimizer (WVGGWO) is used to identify the unknown lumped parameters of SDM of the cell and the module. The proposed WVGGWO is an updated version of the original Grey Wolf Optimizer (GWO). The position update of the GWO has been modified, and the weightage has been provided for the wolf hierarchy. Additionally, by emphasizing the lengthening of each leading wolf's steps towards the others in the earlier search while emphasizing the shortening of the steps while reaching the later iterations, WVGGWO improves both the exploration and exploitation of the original GWO. Four case studies are considered for testing the validity of the proposed algorithm along with the Lambert‐W function. The performance of the proposed approach is compared with seven other well‐known algorithms. The results demonstrate that the suggested approach produces better outcomes than many optimization algorithms.
Role of carbon and nitrogen mineralisation of chitosan and crop straws in ameliorating acidity of acidic Ultisols
Authors: Nkoh Jackson Nkoh , Guan Peng , Shi Ren-yong , Wang Ru-hai , Li Jiu-yu , Xu Ren-kou 
Published: July 2023

Context Carbon (C) and nitrogen (N) transformation processes in soils play an important role in the fluctuation of soil pH. Incorporation of chitosan and crop straws, byproducts from fishery and agriculture, into acidic soils can increase soil pH through decarboxylation, decomposition, N immobilisation and ammonification. Aims The study was designed to evaluate the transformation of organic N and C from chitosan and/or crop straws and their effects on soil physicochemical properties. Methods Chitosan, rice straw and maize straw were incubated with two acidic Ultisols from Langxi (Soil 1) and Yingtan (Soil 2) differing in initial pH. Six treatments were prepared in triplicate: control (no amendment), 4% chitosan, 4% rice straw, 4% maize straw, 2% chitosan + 2% rice straw, and 2% chitosan + 2% maize straw. Soil pH, N transformation and CO2 evolution were estimated at different time intervals. Key results After 40 days of incubation, control soil pH decreased by 0.35 and 0.32 units for Soils 1 and 2, respectively. Rice straw, maize straw, chitosan, rice straw–chitosan and maize straw–chitosan significantly increased soil pH by 0.51, 0.17, 2.27, 1.78 and 2.02 units for Soil 1, and 0.71, 0.16, 0.67, 0.49 and 0.68 units for Soil 2 (P < 0.01). The respective treatments decreased exchangeable acidity by 62%, 51%, 95%, 95% and 95% for Soil 1 and 75%, 69%, 88%, 88% and 87% for Soil 2. In treatments containing chitosan, the pH increase resulted from ammonification of organic N and mineralisation of organic C, with the effect higher in Soil 1 than Soil 2. Conclusions Amending acidic soils with chitosan and crop residues can effectively increase soil pH and slow soil acidification rate. Implications This study provides useful information for amelioration of acidic soils.
Women’s perspectives of direct pharmacy access to oral contraception
Authors: Dev Tara , Buckingham Pip , Mazza Danielle 
Published: July 2023

Background Most oral contraception options require a doctor’s prescription in Australia; however, there are many models of direct pharmacy access that have been successfully implemented internationally. Despite these advancements, the most preferable OTC model for consumers is yet to be explored in the international literature, and no prior studies have determined the potential benefits of implementation in Australia. The aim of this study was to explore women’s perspectives and preferences for models of direct pharmacy access to oral contraceptive pills (OCPs). Methods Women participants (n = 20) aged 18–44 residing in Australia were recruited via posts on a community Facebook page and participated in semi-structured telephone interviews. Interview questions were guided by Andersen’s Behavioural Model of Health Service Use. Data were coded and thematically analysed in NVivo 12, using an inductive process to develop themes. Results Participants’ perspectives and preferences in relation to direct pharmacy OCP access were characterised by: (1) the importance of autonomy, accessibility and decreasing stigma; (2) confidence and trust in pharmacists; (3) health and safety concerns regarding OTC access; and (4) the need for varying OTC models to cater for both experienced and first-time users. Conclusion Women’s perspectives and preferences regarding direct pharmacy OCP access can be used to inform potential pharmacy practice advancements in Australia. While direct pharmacy OCP access is at the nexus of heated political debate in Australia, the potential benefits of being able to access OCPs directly from a pharmacist are evidently salient to women. Australian women’s preferred OTC availability models were identified.