ACS Appl Mater Interfaces
December 2024
Actuators based on liquid crystals have garnered significant attention due to their potential applications in wearable technology and bionic soft robots. Composite films composed of liquid crystal polymer networks (LCNs) and other stimulus-responsive materials exhibit the capability to convert external stimuli into mechanical deformation. However, the development of sunlight-driven actuators presents significant challenges, primarily due to the relatively low intensity of sunlight and the limited conversion efficiency of photothermal materials.
View Article and Find Full Text PDFExceptional points (EPs) have been the subject of wide concern because of their unique physical properties and have produced many related applications. However, up to now, most non-Hermitian metasurfaces related to EPs focus on realizing a single function. It remains a challenge to integrate multiple functions into a single non-Hermitian metasurface while making it dynamically adjustable.
View Article and Find Full Text PDFAnti-counterfeiting technology plays an indispensable role in the high-tech field and various critical application areas. However, traditional anti-counterfeiting approaches currently in widespread use are too simplistic and easily replicated or forged, while advanced technologies with multiple anti-counterfeiting functions remain in the developmental stage. This study presents a novel multiple anti-counterfeiting technique.
View Article and Find Full Text PDFWe proposed a viewing angle controller (VAC) for car co-driver displays (CDDs). This VAC, integrated with the co-driver display, provides necessary information to the co-driver while minimizing driver distraction. It comprises two parallel alignment liquid crystal cells and two negative C films.
View Article and Find Full Text PDFRetroperitoneal appendiceal perforation presents unique challenges in surgical management due to the complex nature of the retroperitoneal space. We present a case of a 57-year-old male with retroperitoneal appendiceal perforation, characterized by the presence of a large amount of gas in the retroperitoneal space. Emergent laparoscopic surgery was performed to address the retroperitoneal involvement.
View Article and Find Full Text PDFACS Appl Mater Interfaces
July 2023
The planar state of a cholesteric liquid crystal (CLC) often exhibits oily streak defects, which negatively impact the characteristics of precision optics, including transmission and selective reflection. In this paper, we introduced polymerizable monomers into liquid crystals and examined the effects of monomer concentration, polymerization light intensity, and chiral dopant concentration on oily streak defects in CLC. With the proposed method of heating cholesteric liquid crystals to the isotropic phase followed by rapid cooling, the oil streak defects presented in the liquid crystal can be successfully eliminated.
View Article and Find Full Text PDFBistable polymer-stabilized cholesteric liquid crystal (LC) devices have been extensively researched due to their energy-saving benefits. Compared to devices with merely transparent and light-scattering states, LC devices with controlled light absorption or changeable color functions are unquestionably more intriguing. In this paper, a polymer-stabilized ion-doped cholesteric LC and an electrochromic layer are used to fabricate a colorable device which can show four operating states: transparent, light-scattering, colored transparent, and colored light-scattering.
View Article and Find Full Text PDFIEEE Trans Neural Netw Learn Syst
May 2024
A start-end frame pair and a motion pattern-based motion synthesis scheme can provide more control to the synthesis process and produce content-various motion sequences. However, the data preparation for the motion training is intractable, and concatenating feature spaces of the start-end frame pair and the motion pattern lacks theoretical rationality in previous works. In this article, we propose a deep learning framework that completes automatic data preparation and learns the nonlinear mapping from start-end frame pairs to motion patterns.
View Article and Find Full Text PDFWe propose two polarization interference filters (PIF and PIF) used in the backlight unit of a liquid crystal display (LCD) to achieve a wide color gamut. Both PIF and PIF consist of two polarizers and two 720° super twisted nematic liquid crystal polymer (LCP) layers, where two polarizers are crossed in PIF, and two polarizers are parallel in PIF The PIFs can eliminate unwanted cyan and yellow parts in the output spectrum, which can improve the color gamut of LCD. In our calculation, when the PIF is employed in the LCD with normal color filter and QD-LED backlight, the color gamut increases from 107.
View Article and Find Full Text PDFIEEE Trans Image Process
July 2022
Deep subspace learning is an important branch of self-supervised learning and has been a hot research topic in recent years, but current methods do not fully consider the individualities of temporal data and related tasks. In this paper, by transforming the individualities of motion capture data and segmentation task as the supervision, we propose the local self-expression subspace learning network. Specifically, considering the temporality of motion data, we use the temporal convolution module to extract temporal features.
View Article and Find Full Text PDFWe demonstrate a wide viewing angle polarization interference filter (PIF), which consists of two crossed polarizers and double liquid crystal layers with opposite twisted direction. The polarization interference effect of the PIF is achieved by the double liquid crystal layers, and an additional compensation layer between the double liquid crystal layers can further improve the optical performance of the PIF. By using the Jones matrix method, we derive the transmittance formula of the PIF with/without compensation layer, which can be used to design any required color filter by selecting the appropriate twist angle and thickness of the liquid crystal layer.
View Article and Find Full Text PDFThe angle-sensitivity is a serious defect of birefringent waveplate, and it draws lots of interest from researchers. In this paper, an angle-insensitive waveplate with inner helix structure is proposed. The super-twisted nematic liquid crystal polymer is used to fabricate the inner helical waveplate, and the retardation-shift is measured and analyzed.
View Article and Find Full Text PDFBackground: The benefit of beta-blockers for secondary prophylaxis of gastric variceal bleeding has limited evidence. Therefore, a systematic review and meta-analysis was conducted to systematically analyze and compare the effect of beta-blockers versus cyanoacrylate injection for patients with gastric variceal bleeding.
Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guidelines will be followed to conduct the present meta-analysis.
IEEE Trans Image Process
September 2020
Although deep neural network methods achieved much success in compressed sensing image reconstruction in recent years, they still have some issues, especially in preserving texture details. In this paper, we propose a new dual-path attention network for compressed sensing image reconstruction, which is composed of a structure path, a texture path and a texture attention module. Motivated by the classical paradigm of image structure-texture decomposition, the structure path aims to reconstruct the dominant structure component of the original image, and the texture path targets at recovering the remaining texture details.
View Article and Find Full Text PDFIEEE Trans Cybern
February 2022
In this article, we tackle the saliency detection task from an interesting perspective: we focus both on salient regions (or foreground) detection and nonsalient regions (or background) detection instead of only the foreground and propose a novel complementarity-aware attention network. It is a unified framework with two branches, namely, positive attention module (PAM) and negative attention module (NAM), for the foreground and background detection, respectively. More specifically, the PAM exploits a position self-attention mechanism to enhance the discriminant ability of feature representation, which can detect most of the salient object regions.
View Article and Find Full Text PDFSome enhanced performances can be obtained by doping multi-walled carbon-nanotube (MWCNT) into self-organized nematic liquid crystal (NLC). However, the dispersion of MWCNT in NLC is very few, thus the enhancement is restricted. In this work, a nickel plated MWCNT (MWCNT@Ni) is synthesized to obtain a relatively high dispersion.
View Article and Find Full Text PDFWe demonstrated a fast switchable dual-model grating based on a polymer-stabilized sphere phase liquid crystal. To form binary periodicity layers, the polymer-stabilized sphere phase liquid crystal precursor was sequence ultraviolet cured at an isotropic and sphere phase. This grating jointly modulated both the phase and the amplitude, had six times the diffraction efficiency of that fabricated with polymer-stabilized blue phase liquid crystal.
View Article and Find Full Text PDFConcentration polarization issues and lithium dendrite formation, which associate inherently with the commercial dual-ion electrolytes, restrict the performance of lithium ion batteries. Single ion conducting polymer electrolytes (SIPEs) with high lithium ion transference numbers ( ≈ 1) are being intensively studied to circumvent these issues. Herein, poly(ethylene--vinyl alcohol) (EVOH) is chosen as the backbone and then grafted with lithium 3-chloropropanesulfonyl(trifluoromethanesulfonyl)imide (LiCPSI) Williamson's reaction, resulting in a side-chain-grafted single ion polymer conductor (EVOH--LiCPSI).
View Article and Find Full Text PDFA liquid crystal (LC) lens array with high light control power and a large aperture using a composited alignment layer is proposed. In our design, the alignment layer is not only used for getting a uniform arrangement of LC molecule, but also for getting a lens-like refractive index distribution in the LC layer when a voltage is applied. Through simple technology processes, a tunable focal length LC lens array with a millimeter scale diameter can be achieved.
View Article and Find Full Text PDFThe structures of flexodomains, which are similar to optical gratings and can be controlled by the amplitude of applied voltage and temperature, were verified through polarizing microscopy and light diffraction techniques. The properties of the optical grating induced by a bent-core nematic liquid crystal in planar cells with varied cell gaps and pretilt angles were studied. The period of optical grating decreases with the increase in the amplitude of the applied voltage and pretilt angle.
View Article and Find Full Text PDFElectro-optical properties of polymer-stabilized sphere phase liquid crystal (PS-SPLC) switching devices are analyzed and validated experimentally. The experimental results show the voltage-dependent transmittance curves of PS-SPLC devices. A diffraction approach, called extended anomalous diffraction approach, is proposed to fit the experimental data.
View Article and Find Full Text PDFIEEE Trans Image Process
January 2017
Graph model is emerging as a very effective tool for learning the complex structures and relationships hidden in data. In general, the critical purpose of graph-oriented learning algorithms is to construct an informative graph for image clustering and classification tasks. In addition to the classical K-nearest-neighbor and r-neighborhood methods for graph construction, l-graph and its variants are emerging methods for finding the neighboring samples of a center datum, where the corresponding ingoing edge weights are simultaneously derived by the sparse reconstruction coefficients of the remaining samples.
View Article and Find Full Text PDFWe proposed a dual-period phase grating using a polymer-stabilized blue phase liquid crystal (PS-BPLC). High efficiencies of 38% for the short-period phase grating and 30% for the long-period phase grating have been achieved because of the electric-field-induced rectangular-like phase profile of a PS-BPLC, which agrees quite well with the simulation results. The diffraction angle and the diffraction efficiency can be alternatively tuned by a bias voltage and intensity of applied voltage.
View Article and Find Full Text PDFLithium-sulfur batteries are highly promising for electric energy storage with high energy density, abundant resources and low cost. However, the battery technologies have often suffered from a short cycle life and poor rate stability arising from the well-known "polysulfide shuttle" effect. Here, we report a novel cell design by sandwiching a sp(3) boron based single ion conducting polymer electrolyte film between two carbon films to fabricate a composite separator for lithium-sulfur batteries.
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