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Hopping cyclic codes (HCCs) are (non-linear) cyclic codes with the additional property that the $n$ cyclic shifts of every given codeword are all distinct, where $n$ is the code length. Constant weight binary hopping cyclic codes are also known as optical orthogonal codes (OOCs). HCCs and OOCs have various practical applications and have been studied extensively over the years. The main concern of this paper is to present improved Gilbert-Varshamov type lower bounds for these codes, when the minimum distance is bounded below by a linear factor of the code length. For HCCs, we improve the previously best known lower bound of Niu, Xing, and Yuan by a linear factor of the code length. For OOCs, we improve the previously best known lower bound of Chung, Salehi, and Wei, and Yang and Fuja by a quadratic factor of the code length. As by-products, we also provide improved lower bounds for frequency hopping sequences sets and error-correcting weakly mutually uncorrelated codes. Our proofs are based on tools from probability theory and graph theory, in particular the McDiarmid's inequality on the concentration of Lipschitz functions and the independence number of locally sparse graphs., Comment: 14 pages, submitted

This paper presents an empirical evaluation of the performance of the Generative Pre-trained Transformer (GPT) model in Harvard's CS171 data visualization course. While previous studies have focused on GPT's ability to generate code for visualizations, this study goes beyond code generation to evaluate GPT's abilities in various visualization tasks, such as data interpretation, visualization design, visual data exploration, and insight communication. The evaluation utilized GPT-3.5 and GPT-4 to complete assignments of CS171, and included a quantitative assessment based on the established course rubrics, a qualitative analysis informed by the feedback of three experienced graders, and an exploratory study of GPT's capabilities in completing border visualization tasks. Findings show that GPT-4 scored 80% on quizzes and homework, and TFs could distinguish between GPT- and human-generated homework with 70% accuracy. The study also demonstrates GPT's potential in completing various visualization tasks, such as data cleanup, interaction with visualizations, and insight communication. The paper concludes by discussing the strengths and limitations of GPT in data visualization, potential avenues for incorporating GPT in broader visualization tasks, and the need to redesign visualization education., Comment: vis short papge

This study sets off to fill in a gap in the L2 research literature on empty categories in Mandarin Chinese by examining second language (L2) acquisition of a type of Chinese verb-less constructions by English-speaking learners. The verb-less constructions in question are Chinese gapping-like constructions which bear a surface resemblance to English canonical gapping constructions. Despite the surface similarities shared by Chinese gapping-like constructions and English canonical gapping, the two verb-less constructions derive from different syntactic representations, which is reflected in their different distributions. Moreover, there exist some semantic constraints unique to Chinese gapping-like constructions. The present study investigates both offline acceptability judgment and online production of Chinese gapping-like constructions by native MC speakers and L2 learners. It sets off to explore whether the similarities and differences between Chinese and English affect the developmental course and ultimate attainment of L2 Chinese gapping-like constructions at both the narrow syntax and the interface levels. The present study aims to contribute to the ongoing debates on two major topics in L2 research: i. the learnability of interface properties; ii. the effect of L1. 29 native Chinese speakers and 70 English-speaking learners of Mandarin Chinese ranging from beginners to advanced learners participated in the study, taking an online elicitation imitation task as well as an offline acceptability judgment task. It is found that both narrow syntactic properties and interface properties pose challenges in L2 acquisition of Chinese gapping-like VBE (Verb Ellipsis), which indicates that learnability issues are not specific to interfaces. The present study regards L1-L2 asymmetry as the primary cause for the persistent non-nativelike L2 attainment at both the narrow syntax level and the interface level. Meanwhile, other factors such as proficiency and input also play important roles in shaping learners’ L2 grammars and L2 speech production mechanisms.

Paraneoplastic pemphigus (PNP) is an autoimmune bullous disease associated with underlying neoplasms and characterized by antibodies against desmoglein 3 (Dsg 3) and plakins. Autoantibodies against desmoglein 3 in sera of patients with PNP have been proven to cause acantholysis in vivo in neonatal mice. As a member of the plakin family, autoantibodies against desmoplakin were detected frequently by immunoprecipitation in the sera of PNP. The recombinant C-terminus of desmoplakin was expressed and purified to adsorb the specific autoantibodies against the C-terminus of desmoplakin. In vitro dispase-dependent keratinocyte dissociation assay and in vivo IgG passive transfer into neonatal mice assay were performed, followed by the electronic microscopy examination and TUNEL assay. We found that anti-C terminus of desmoplakin autoantibodies caused blisters and acantholysis in mice skin at a dose-dependent manner. Moreover, dissociated fragments were observed after incubation with the purified IgG against desmoplakin, compared with normal human IgG (P-value =0.0207). The electronic microscopy examination showed the disconnection of keratin intermediate filaments from desmosomes. Lastly, apoptosis of keratinocytes in the TUNEL assay was all detected in the skins of neonatal mice after injection of the anti-C terminus of desmoplakin autoantibodies. Taken together, the study suggests that autoantibodies against the C-terminus of desmoplakin might be pathogenic in PNP.

A new flame retardant, DM/PEI/MWCNT, was prepared by self-assembly method based on non-covalent interactions between hydroxyl and amino groups on the surface of hydroxyl multi-walled carbon nanotubes (MWCNT), polyethyleneimine (PEI) and diatomite (DM). The flame-retardant composites were prepared by adding DM/PEI/MWCNT to room-temperature vulcanisated silicone rubber (RTV-silicone). The structure of the flame retardant and composites was characterised by polarising light microscope, scanning electron microscopy and Fourier-transform infrared spectroscopy. The flame retardancy of composites was studied by limited oxygen index and cone calorimeter measurement. Results showed that RTV-silicone composites with DM/PEI/MWCNT owned better flame retardancy. In addition, DM/PEI/MWCNT exhibited better compatibility in silicone rubber than that of unmodified DM, and the tensile properties of RTV-silicone/DM/PEI/MWCNT composites were improved compared to pure RTV-silicone.

With the rapid development of artificial intelligence, the technology of human-computer interaction is becoming more and more mature. The variety of terminal products equipped with conversational agents are more diverse, and the product penetration rate is also getting higher and higher. This study focused on the problems of the conversational agent in response. In this paper, we presented a study with 20 participants to explore how to design the expression ways of conversational agents’ feedback with considerations of users’ affective experience. We explored the performance of three different expression ways (general way, implicit way, and explicit way) in different time and different functions. And we examined whether users of different genders have different preferences for these three expression ways. Therefore, we used the “Wizard of Oz techniques” to simulate a real environment for communication between the user and the conversational agent. In this study, we combined quantitative scoring (five aspects: affection, confidence, naturalness, social distance, and satisfaction) with qualitative interviews. The results showed that: (1) the user’s affective experience should be considered in expression ways’ design; (2) different expression ways had different performances in different functions, and the explicit way performed better in most situations; (3) male users seemed to rate the agent’s expression performance higher than female users.

The traditional acid leaching process for releasing valuable metals from spent lithium-ion batteries (LIBs) is inefficient and inevitably consumes large amounts of reductants. In this study, a novel process, based on a reduction thermal treatment and reductant-free acid leaching, for recycling valuable metals from spent LIBs has been developed. First, a thermodynamics calculation was performed to judge whether the reducing reaction between LiCoO2 and graphite can occur or not. Then, reduction thermal treatment experiments were conducted. The process was tested by a thermogravimetry/differential thermal analysis method, and reaction products were measured by X-ray powder diffraction and X-ray photoelectron spectroscopy. The experimental results agree well with thermodynamics analysis, and the desired CoO and Li2CO3 were obtained under the optimum processing conditions of 600 °C, 120 min, and molar ratio of LiCoO2 to graphite of 2:1. Finally, almost 100% Li and Co were easily leached from the reaction produ...

Crystallization of perovskite structure chromites (ACrO3) in aqueous conditions is difficult owing to the amphoteric nature of the Cr3+ in the alkaline-mediated reaction conditions. This is especially true for the small metal cations at the A-site with large distortion angle of CrO6 octahedral and small Goldschmidt tolerance factors. Here, we performed a progressive dehydration crystallization strategy to synthesize four RECrO3 with the smallest radii of rare earth elements (Er, Tm, Yb, Lu) in mild hydrothermal conditions. Profile refinement of the high-resolution powder X-ray diffraction results indicated slightly longer unit cell parameters of a and c in our samples with a higher distorted angle of CrO6 octahedral units along ⟨010⟩ direction. All of the samples show rounded rectangle plate morphology with uniform distribution of particle sizes. These four RECrO3 crystals can only form in a very narrow mineralization temperature range, i.e., 260-280 °C and 4.45-6.24 M of KOH. HRTEM results indicated that the normal crystallographic direction is ⟨001⟩, and the lattice of steps at the edge of elliptic rounded crystal is consistent with the bulk, which demonstrated single crystalline nature of the as-obtained crystals. Room-temperature Raman and FT-IR spectra reveal a continuous symmetry mode shift-dependent on the radii of A-site rare-earth cations. Temperature-dependent magnetization curves of RECrO3 show typical antiferromagnetism to paramagnetism transition with Néel temperature of 93, 90, 86, and 83 K for ErCrO3, TmCrO3, YbCrO3, and LuCrO3, respectively. Samples of YbCrO3 and LuCrO3 show clear magnetization reversal and exchange bias phenomena below their Néel points. This paper indicates that the coupling of magnetic exchange in perovskite structure oxides could be tailorable in mild hydrothermal condition, towards the exploration of new magnetic and other physical properties.

TiO2-SiO2 is a kind of binary component glass material with excellent properties such as high heat impact resistance, welding ability, and the size of the material is insensitive to temperature change. Based on the principle of Chemical Vapor Deposition (CVD), we used silicon tetrachloride and titanium tetrachloride as the raw materials for the preparation of this glass. In this research, we studied the morphology, structure, and particle size distribution of TiO2-SiO2 binary glass particles. The experimental results show that the deposition particles are spherical amorphous nanoparticles with a size of about 100nm, and there is no SiO2 or TiO2 crystalline phase in the particles. This particle structure overcomes the characteristic that TiO2 is easily crystallized in other preparation methods, making preparation for TiO2-SiO2 binary glass possible.

In order to solve the problem of state estimation and fault detection for a class of stochastic switched nonlinear system with unknown characteristics of observation noise change, a system state estimation algorithm based on interactive multiple model and unscented Kalman filter (IMM-UKF) is proposed. The algorithm uses the UKF to estimate the state of each subsystem at different time points, then fuses the state estimation results of different subsystems to obtain the final state estimation, and realizes the estimation of the real state of the system. In order to achieve real-time tracking of system observation noise, a fuzzy controller is established to adjust the observation noise of IMM- UKF in real time, and a fuzzy adaptive IMM-UKF algorithm (FAIMM-UKF) is proposed. For actuator failure in a class of stochastic switched nonlinear systems, FAIMM-UKF is used to estimate the system state. Based on the result of the state estimation, residual and residual evaluation functions are established to detect the actuator fault. Finally, the effectiveness of the proposed algorithm is verified by simulation experiment.

Gallium nitride (GaN) is a promising semiconductor material with high electron mobility, larger sheet carrier concentration, and wide energy bandgap. Open-gate AlGaN/GaN high electron mobility transistors (HEMTs) are shown to be an effective method for detection polar liquids. In this work, the pH sensing response of an open-gate HEMT is investigated. The device exhibits a good linear pH detection performance. The pH response of the device is less sensitive at lower source-drain voltage where the transconductance of the device is small. But the high leakage current accelerate the polar liquid corrosion of the electrode surface metal at high source-drain voltage. This paper analyzes the reasonable calculation method to choice the suitable scan range of source-drain voltage.

In order to develop reliable constitutive equations for the simulation, the hot deformation behavior of FV520B steel was investigated through isothermal compression tests in a wide range of temperatures from 900 °C to 1100 °C at an interval of 50 °C and strain rate from 0.01 to 10 s−1 on Gleeble-1500D simulator. The effects of temperature and strain rate on deformation behavior were represented by Zener-Holloman parameter in an exponent-type equation of Arrhenius constitutive. The influence of strain was incorporated in the constitutive analysis by material constants expressed as a polynomial function of strain. The constitutive equation (considering the compensation of strain) could precisely predict the flow stress only at strain rate 0.01 s−1 except at the temperatures of 900 °C and 1000 °C, whereas the flow stress predicted by a modified equation (incorporating both the strain and strain rate) demonstrated a well agreement with the experimental data throughout the entire range of temperatures and strain rates. Correlation coefficient (R) of 0.988 and average absolute relative error (AARE) of 5.7% verified the validity of developed equation from statistical analysis, which further confirmed that the modified constitutive equation could accurately predict the flow stress of FV520B steel.