We propose a light shutter device using dichroic-dye-doped liquid crystals (LCs) whose Bragg reflection wavelength is set to be infrared by controlling the pitch of cholesteric liquid crystals ...(ChLCs). A dye-doped long-pitch ChLC cell is switchable between the dark planar state and the transparent homeotropic state. It has the advantages of high transmittance, low operation voltage, and an easy fabrication process relative to previous LC light shutter devices. The proposed light shutter device is expected to achieve high visibility for transparent organic light-emitting diode displays and emerging smart windows, which can be used in airplanes, cars, and other similar applications.
The facile and affordable fabrication of sensors that can detect carcinogenic benzene has remained a long-standing challenge, as sophisticated nano-architectures and/or sensing films are essential to ...ensure benzene selectivity. Herein, we report a raisin bread-structured film fabricated by mixing two different types of oxide hollow spheres, as a novel, cost-effective platform for the highly selective and sensitive detection of benzene. The film comprises catalytic Pd-Co3O4 (i.e., raisins) and gas-sensing SnO2 hollow spheres (i.e., bread), prepared by ultrasonic spray pyrolysis. In contrast to films of pure SnO2 or Pd-Co3O4 hollow spheres, which are partially selective to reactive gases such as xylene/toluene/ethanol, raisin bread films are highly selective to less reactive benzene. Thus, an array of the SnO2, Pd-Co3O4, and raisin bread sensors enables exclusive benzene identification with principal component analysis. The superior benzene-sensing properties of raisin bread sensors are attributed to the oxidative consumption of reactive gases by the catalytic raisins, whereas less-consumed benzene sensitively reacts with the gas-sensing bread. This is supported by proton transfer reaction-quadrupole mass spectrometry analysis. This work provides a simple, rational strategy to attain gas selectivity to chemically stable benzene and is expected to trigger the development of ubiquitous portable devices to monitor airborne benzene.
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•Raisin bread film is fabricated by mixing two different oxide hollow spheres.•The film shows high selectivity to benzene gas.•The sensing mechanism is confirmed via mass spectrometry-based analysis.•An electric nose composed of sensors with different gas selectivity is designed.•The exclusive identification of benzene in the electric nose is demonstrated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We propose a light shutter device using dye-doped cholesteric liquid crystals for a high-visibility see-through display. In the focal-conic state, the proposed device can perfectly block the ...background image through simultaneous use of light scattering and absorption effects in a single-layered structure. By switching the proposed device placed at the backside of a see-through display, we can choose transparent or high-visibility display modes in a see-through display.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
A dye-doped LC/polymer light shutter with a polymer structure that is formed using the thermally-induced phase separation (TIPS) method is demonstrated. The TIPS method does not include any chemical ...reaction, and thus there is no degradation of the dye during the fabrication process. The light shutter can be fabricated quickly because the optical performance is not affected by the cooling time. The fabricated TIPS cell exhibits excellent optical performance, such as a low haze value of 0.5% in the initial transparent state, and a high haze value of 99.1% in the opaque state with a superior black color. This approach can be used for the high image quality of see-through displays using organic light-emitting diodes.
•We report the fabrication of an initially-transparent dye-doped LC/polymer light shutter.•The fabricated cell exhibits very low haze in the initial transparent state, and high haze in the opaque state.•Thermally induced phase separation method has easy fabrication process and reduces the fabrication time.•Our fabricated cell shows superior black color without dye degradation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
To reduce power consumption by light shutters, bistable light shutters using cholesteric liquid crystal have been proposed. However, these bistable light shutters, which utilize the scattering of the ...incident light, are switchable only between transparent and translucent states. In this work, we successfully demonstrate a bistable light shutter that is switchable between transparent and opaque states because it utilizes not only scattering, but also the absorption of the incident light. We hide the objects behind a display panel and provide black color by switching the light shutter that is positioned at the backside of a see-through display. We realized a good opaque state by optimization of the electrode structure.
We report a thermal curing method for fabrication of a dye-doped polymer-stabilized liquid crystal (PSLC) light shutter, which can prevent the decrease in absorption and discoloration of the dye ...caused by the UV curing process. We found that the measured transmittance in the opaque state of a dye-doped PSLC cell fabricated by thermal curing was approximately 35% lower than that of a dye-doped PSLC cell fabricated by UV curing. Thermal curing can be an alternative approach for fabrication of a dye-doped PSLC light shutter which can be used to provide high visibility of a see-through display.
•We report a thermal curing method for fabrication of a dye-doped polymer-stabilized liquid crystal (PSLC) light shutter.•The UV exposure to an LC mixture including photo-initiator caused the degradation of the dye molecules.•A dye-doped PSLC cell fabricated by thermal curing can be used to provide high visibility of a see-through display.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
By switching a light shutter placed at the backside of a see-through display, we can select the transparent or high-visibility mode of the display panel. In this paper, we introduce technologies for ...liquid crystal (LC) light shutters that can scatter and absorb the incident light simultaneously, which is preferable for display applications. A light shutter for display applications can be realized in the normally-opaque mode by using a double-layered structure using cholesteric LCs or a single-layered structure using dye-doped cholesteric LCs. Whereas, it can be realized in the normally-transparent mode by using dye-doped polymer-networked LC cells using negative or positive LCs. Operation of each of the technologies is reviewed and the performance of these technologies is compared in this paper.
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One of the most important processes in a machine learning-based natural language processing is to represent words. The one-hot representation that has been commonly used has a large size of vector ...and assumes that the features that make up the vector are independent of each other. On the other hand, it is known that word embedding has a great effect in estimating the similarity between words because it expresses the meaning of the word well. In this study, we try to clarify the correlation between various terms in the biomedical texts based on the excellent ability of estimating similarity between words shown by word embedding. Therefore, we used word embedding to find new biomarkers and microorganisms related to a specific diseases.
In this study, we try to analyze the correlation between diseases-markers and diseases-microorganisms. First, we need to construct a corpus that seems to be related to them. To do this, we extract the titles and abstracts from the biomedical texts on the PubMed site. Second, we express diseases, markers, and microorganisms' terms in word embedding using Canonical Correlation Analysis (CCA). CCA is a statistical based methodology that has a very good performance on vector dimension reduction. Finally, we tried to estimate the relationship between diseases-markers pairs and diseases-microorganisms pairs by measuring their similarity.
In the experiment, we tried to confirm the correlation derived through word embedding using Google Scholar search results. Of the top 20 highly correlated disease-marker pairs, about 85% of the pairs have actually undergone a lot of research as a result of Google Scholars search. Conversely, for 85% of the 20 pairs with the lowest correlation, we could not actually find any other study to determine the relationship between the disease and the marker. This trend was similar for disease-microbe pairs.
The correlation between diseases and markers and diseases and microorganisms calculated through word embedding reflects actual research trends. If the word-embedding correlation is high, but there are not many published actual studies, additional research can be proposed for the pair.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We fabricated a light shutter using plastic substrates for high visibility of a flexible see-through display. To achieve a flexible light shutter using liquid crystals (LC), it is essential to ...maintain the cell gap when the light shutter is bent. We studied methods to fabricate flexible LC light shutters using plastic substrates. We demonstrated light shutters that are initially transparent and flexible with or without polymer walls. We have elucidated that polymer walls and networks provide mechanical stability against the bending of an LC light shutter without any degradation in the electro-optic characteristics. We predict that a flexible light shutter provides not only high visibility but also mechanical stability to a flexible see-through display by positioning it at the back of a flexible see-through display panel.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
We propose a cholesteric liquid crystal device with a three-terminal electrode structure that can be operated in both the dynamic and the bistable modes. Fast switching (less than 5 ms) between the ...planar and the in-plane-field-induced states can be realized by applying an in-plane electric field, and conventional bistable switching between the planar and focal conic states can be realized by applying a vertical electric field.
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