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My enemy’s enemies are my friends:Alternative sources of support in multi-party races

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Economic and Political Studies 2024年第3期12卷 285-317页

作者： Carlos Costa School of Public and International Affairs Wright State UniversityDaytonOHUSA

The research on redistributive strategies to secure support has been dominated by a core and swing voter model,which pits two parties against each other in a costly race for *** are other options beyond targeting either swing or one’s own core voters?This paper identifies a political scenario where core supporters from other parties are viable targets and sets out to test three dimensions that indicate when actors can effectively target *** paper’s main expectation is that by accounting for voters’ideological affinity,levels of fragmentation,and the potential to deliver their votes,parties can effectively target other parties’core *** case of Brazil’s Bolsa Famılia delivers evidence for the hypotheses.

关键词： Multi-party races coreand swing conditionalcash transfer BolsaFamılia

Revealing the microstructures of metal halide perovskite thin films via advancedtransmission electron microscopy

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Chinese Physics B 2024年第9期33卷 30-41页

作者： Yeming Xian Xiaoming Wang Yanfa Yan Department of Physics and Astronomy and wright Center for Photovoltaics Innovation and Commercialization The University of ToledoToledoOhio 43606United States

Metal halide perovskites (MHPs) are excellent semiconductors that have led to breakthroughs in applications in thinfilmsolar cells, detectors, and light-emitting diodes due to their remarkable optoelectronic properties and defect ***, the performance and stability of MHP-based devices are significantly influenced by their microstructures includingthe formation of defects, composition fluctuations, structural inhomogeneity, etc. Transmission electron microscopy(TEM) is a powerful tool for direct observation of microstructure at the atomic-scale resolution and has been used to correlatethe microstructure and performance of MHP-based devices. In this review, we highlight the application of TEMtechniques in revealing the microstructures of MHP thin films at the atomic scale. The results provide critical understandingof the performance of MHP devices and guide the design of strategies for improving the performance and stability ofMHP devices.

关键词： perovskite defect inhomogeneity transmission electron microscopy

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High Sensitivity Digital Instantaneous Frequency Measurement Receiver for Precise Frequency Analysis

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Journal of Computer and Communications 2024年第1期12卷 177-190页

作者： Bilal Abdulhamed Chien-In Henry Chen Department of Electrical Engineering Wright State University Dayton Ohio USA

There are numerous applications, such as Radar, that leverage wideband technology. However, the presence of noise introduces certain limitations and challenges. It is crucial to harness wideband technology for applications demanding the rapid and precise transmission of diverse information from one point to another within a short timeframe. The ability to report a signal without tuning within the input bandwidth stands out as one of the advantages of employing a digital wideband receiver. As indicated, a digital wideband receiver plays a pivotal role in achieving high precision and accuracy. The primary distinction between Analog and Digital Instantaneous Frequency Measurement lies in the fact that analog Instantaneous Frequency Measurement (IFM) receivers have traditionally covered extensive input bandwidths, reporting one accurate frequency per short pulse. In the contemporary landscape, digital IFM systems utilize high-sampling-rate Analog-to-Digital Converters (ADC) along with Hilbert transforms to generate two output channels featuring a 90-degree phase shift. This paper explores the improvement of sensitivity in current digital IFM receivers. The optimization efforts target the Hilbert transform and autocorrelations architectures, aiming to refine the system’s ability to report fine frequencies within a noisy wide bandwidth environment, thereby elevating its overall sensitivity.

关键词： Digital Wideband Receiver Instantaneous Frequency Measurement (IFM) Receiver

Synthetic brochosomes:Design,synthesis,and applications

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Nano Research 2024年第2期17卷 734-742页

作者： Lin Wang Jinsol Choi Tak-Sing Wong Department of Mechanical Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA Materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Biomedical Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA

Brochosomes,which are nanoscopic buckyball-shaped granules produced by leafhoppers,are one of the most intricate structures discovered in *** functions of brochosomes have been proposed but only a few have been experimentally validated due to the challenge of fabricating their synthetic *** in micro-and nanofabrication have recently led to the emergence of synthetic brochosomes,opening up new possibilities for innovative *** review explores the early discovery of natural brochosomes and their geometrical features,followed by the recent progress in fabricating synthetic brochosomes and their *** on future applications and challenges in the scalable manufacturing of synthetic brochosomes are discussed.

关键词： synthetic brochosomes leafhopper antireflection superhydrophobicity surface-enhanced Raman scattering photocatalyst energy harvesting

Analysis of synthetic parameters for coating aluminum powders with phenyltriethoxysilane coupling agent and their effects on powder flow behavior

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Particuology 2024年第7期90卷 412-417页

作者： Lillian M.Mawby Bellamarie Ludwig Benjamin J.Lear Department of Chemistry The Pennsylvania State UniversityUniversity ParkPA16802USA Applied Research Laboratory The Pennsylvania State UniversityUniversity ParkPA16802USA

Though silanization of aluminum powder is currently used to improve its flow properties,for use as an alternative fuel source,there are a wide range of experimental parameters for the process and not all of them have been thoroughly *** this is complete,it is unknown if the process is optimized in terms of time,efficiency,and ***,we report on a study into the effects of changes in humidity,degree of agitation,reaction temperature,and curing time upon the deposition of phenyl triethoxysilane into 20μm(d50)aluminum *** confirm the deposition of the coating via diffuse reflectance infrared spectroscopy and x-ray photoelectron *** then characterize the coated particles using apparent density measurements and Carney flow *** analysis of variance,we find that,of the parameters explored,only changes in cure time and reaction temperature provide meaningful changes to the apparent density,while none of our parameters produced statistically significant changes in Carney flow ***,we conclude that,when optimizing silanization of aluminum particles,environmental control of humidity is unneeded and that the reaction can be run with minimal *** ability to largely ignore these parameters is a benefit to large-scale processing.

关键词： Aluminum powder Silane Fluidization Apparent density Carney flow

Enhanced Wideband Frequency Estimation via FFT: Leveraging Polynomial Interpolation and Array Indexing

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Journal of Computer and Communications 2024年第1期12卷 35-48页

作者： Kiran Jayarama Chien-In Henry Chen Digital Receiver Laboratory Department of Electrical Engineering Wright State University Dayton OH USA

Accurate frequency estimation in a wideband digital receiver using the FFT algorithm encounters challenges, such as spectral leakage resulting from the FFT’s assumption of signal periodicity. High-resolution FFTs pose computational demands, and estimating non-integer multiples of frequency resolution proves exceptionally challenging. This paper introduces two novel methods for enhanced frequency precision: polynomial interpolation and array indexing, comparing their results with super-resolution and scalloping loss. Simulation results demonstrate the effectiveness of the proposed methods in contemporary radar systems, with array indexing providing the best frequency estimation despite utilizing maximum hardware resources. The paper demonstrates a trade-off between accurate frequency estimation and hardware resources when comparing polynomial interpolation and array indexing.

关键词： Scalloping Loss Goertzel’s Algorithm Super-Resolution Fast Fourier Transform (FFT) Decimation in Frequency (DIF) Decimation in Time (DIT) Spectral Leakage Frequency Estimation

Displacement-pressure biparametrically regulated softness sensory system for intraocular pressure monitoring

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National Science Review 2024年第6期11卷 159-168页

作者： Yu Cheng Yifei Zhan Fangyi Guan Junli Shi Jingxiao Wang Yi Sun Muhammad Zubair Cunjiang Yu Chuan Fei Guo Department of Materials Science and Engineering Southern University of Science and Technology Department of Engineering Science and Mechanics Pennsylvania State University Department of Biomedical Engineering Pennsylvania State University Department of Materials Science and Engineering Materials Research Institute Pennsylvania State University

High intraocular pressure(IOP) is one of the high-risk pathogenic factors of glaucoma. Existing methods of IOP measurement are based on the direct interaction with the cornea. Commercial ophthalmic tonometers based on snapshot measurements are expensive, bulky, and their operation requires trained *** contact lenses are easy to use, but they may block vision and cause infection. Here, we report a sensory system for IOP assessment that uses a soft indentor with two asymmetrically deployed iontronic flexible pressure sensors to interact with the eyelid-eyeball in an eye-closed situation. Inspired by human fingertip assessment of softness, the sensory system extracts displacement-pressure information for soft evaluation, achieving high accuracy IOP monitoring(>96%). We further design and custom-make a portable and wearable ophthalmic tonometer based on the sensory system and demonstrate its high efficacy in IOP screening. This sensory system paves a way towards cost-effective, robust, and reliable IOP monitoring.

关键词： intraocular pressure tonometer deep learning softness iontronic sensor

An effective gauge field theory of the nucleon interactions

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Communications in Theoretical Physics 2024年第10期76卷 78-86页

作者： Eduard Boos Skobeltsyn Institute of Nuclear Physics Lomonosov Moscow State University Faculty of Physics Lomonosov Moscow State University

We discuss the possibility of constructing an effective gauge field theory of the nucleon interactions based on the ideas of isotopic invariance as well as hypercharge invariance as a local gauge symmetry and spontaneous breaking of this symmetry. The constructed effective field theory predicts the structure of interactions of protons and neutrons with ρ- and σ-mesons, and with pi-mesons and photons, as well as interactions of these particles with each other. The Lagrangian of the theory consists of several parts involving dimension 4 and 5 gauge invariant operators. Feynman rules for physical degrees of freedom that follow on from the Lagrangian define the structure of diagrams for one-boson exchanges between nucleons, predicting the internucleon one-boson-exchange potential as well as nucleon scattering amplitudes. The range of applicability of the effective theory is discussed and estimates are made of the resulting coupling constants. The theory predicts the mass of the neutral ρ0-meson to be about 1 MeV larger than the mass of the charged mesons ρ±. The vector ω-meson, which is a sterile particle with respect to the considered gauge group SUI（2） × UY（1）, can be added to the scheme via a gauge-invariant operator of dimension 5, as shown in the appendix.

关键词： gauge invariance nucleon interactions spontaneous symmetry breaking

Indispensable gutter layers in thin-film composite membranes for carbon capture

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Green Energy & Environment 2024年第8期9卷 1220-1238页

作者： Gengyi Zhang Haiqing Lin Department of Chemical and Biological Engineering University at Buffalo The State University at New York

Industrial thin-film composite(TFC) membranes achieve superior gas separation properties from high-performance selective layer materials,while the success of membrane technology relies on high-performance gutter layers to achieve production scalability and low-cost manufacturing. However, the current literature predominantly focuses on the design of polymer architectures to obtain high permeability and selectivity, while the art of fabricating gutter layers is usually safeguarded by industrial manufacturers and appears lackluster to academic researchers. This is the first report aiming to provide a comprehensive and critical review of state-of-the-art gutter layer materials and their design and modification to enable TFC membranes with superior separation performance. We first elucidate the importance of the gutter layer on membrane performance through modeling and experimental results. Then various gutter layer materials used to obtain high-performance composite membranes are critically reviewed, and the strategies to improve their compatibility with the selective layer are highlighted, such as oxygen plasma treatment, polydopamine deposition, and surface grafting. Finally, we present the opportunities of the gutter layer design for practical applications.

关键词： Thin-film composite membranes Gutter layer Gas separation Carbon capture