bluuebunny/crossref_metadata_2025 huggingface dataset:
P‐106: Highly Luminescent Blue Light‐Emitting Diodes Based on Quasi‐2D Multi‐Cation Perovskites
Authors: Wu Yongwei , Feng Zhengyu , Yang Guang , Jiang Pei , He Bo , Duan Miao , Yin Yongming , Chen Shujhih , Li Dongze , Zhou Hang , Zhang Xin , Zhang Shengdong
Published: September 2020

Quasi‐2D perovskites, typically with a standard formula of L2An‐1MnX3n+1, have recently attracted significant attention due to their promising optoelectronic properties. Normally, they contain a mono cation (e.g., butylammonium (BA+) or phenylethylammonium (PEA+) for “L” and methylammonium (MA+) or formamidinium (FA+) for “A”). In this work, multiple cation‐substitution strategy was used to improve the luminescence and emission efficiency of perovskite thin films. As a result, a smooth, compact surface morphology of blue emission perovskite thin films was achieved, with a high photoluminescence quantum yield of 53%. Finally, the corresponding perovskite light‐emitting diodes (PeLEDs) reaches a brightness of 220 cd/m2, and a maximum external quantum efficiency of 0.83%.
P‐109: Temperature‐dependent Forward Voltage of AlGaInP‐based Red Micro‐LEDs
Authors: Wang Yan , Lu Bo , Liu Chuanbiao , Sher Chin‐Wei , Kuo Hao‐Chung , Hyun Byung‐Ryool , Liu Zhaojun
Published: September 2020

Temperature‐dependent electrical characteristics and voltages (dVf/dT) of AlGaInP Micro‐LEDs were investigated. The J‐V curves of the Micro‐LEDs indicate the existence of a big resistance. The measured (dVf/dT) was ‐3 mV/K, which is higher than the expected value in Shockley model. This was attributed to a resistance, leading to higher temperature sensitivity.
P‐113: In Situ Fabrication of Organic‐Inorganic Perovskite Polymer Composite Films for Ultrawide Color Gamut LCD display
Authors: Li Xiang , Qu Xiangwei , Wen Zuoliang , Xu Bing , Wang Kai , Sun Xiao Wei
Published: September 2020

We report an ultrawide color gamut LCD displays made of organic‐inorganic perovskite polymer composite film. The color gamut of the display is 123% and 92% that of the NTSC 1953 and Rec. 2020, respectively. The combination of better stability and improved color purity of the perovskite material provides a viable approach for LCD backlights.
P‐211: Late‐News‐Poster: Quantum Dot Patterns in Molecularly Ordered Matrix for Emissive Displays with Wide Color Gamut
Authors: Kang Suft , Lee Sin-Hyung , Lee Sin-Doo
Published: September 2020

We demonstrate the quantum dot (QD) hybrid patterns produced from uniformly dispersed QDs in the host matrix with the molecular order. The molecular ordering of the liquid crystalline polymer (LCP) as a host medium plays a critical role on the uniform dispersion of the QDs. The uniformity of the QD patterns and the emission intensity are found to be greatly enhanced by the molecular order compared to the conventional cases. Our emissive color display composed of the QD hybrid patterns shows the emission spectra with the color gamut extended to 87 % of the BT.2020 standard. Our approach will provide a simple and viable method of constructing the QD‐based emissive display with wide color gamut in a cost‐effective manner.
P‐213: Late‐News‐Poster: Electroluminescence of Oxide Phosphor in Metal‐Oxide‐Semiconductor Structure
Authors: Kang Taewook , Park Jehong , Park Boowon , Lim Jimin , Kang Hyunwoo , Jeong Hyundon , Kim Jongsu
Published: September 2020

The green Zn2SiO4:Mn2+ phosphor film for electroluminescence (EL) was fabricated through a thermal annealing process of spin coated film on n‐type silicon wafer as a semiconductor electrode. The oxide phosphor was placed in metal‐oxide‐semiconductor (MOS) structure, where indium tin oxide was used as a top transparent electrode. The EL device showed the high‐purity green emission spectrum at 525 nm. Its luminance‐voltage and frequency dependence showed the increasing trend up to 100 V and 1 kHz.
P‐116: Soft and Reconfigurable Wearable LED Display Using Soft Modular Blocks
Authors: Yoon Jaeyoung , Hong Yongtaek
Published: September 2020

We present a method for assembling fundamental blocks that are reconfigurable based on soft modular blocks and stretchable interconnects. The soft modular blocks are electrically connected via a stretchable interconnect and the electrical properties of the resulting blocks are stable even under the external strain. We demonstrated various configurations of modular LED blocks including 4 by 4 LEDs and wearable LED displays onto the human skin.
P‐119: Modeling of Mechanical Effects in Flexible Display
Authors: Chen Zhen-Peng , Li Shan-Shan , Wang Shuai , Lee Bong-Geum , Yuan Ze , Yu Xiaojun
Published: September 2020

A series of finite element analysis (FEA) models have been established to study the mechanical effects in a flexible AMOLED display module, in scenarios of outward‐folding, rolling and ball drop, etc. Analysis is conducted to verify the validity of such models. The simulation results are in good agreement with the designed experiments. Accurate modeling of these effects can be significant in guiding the module stack‐up design of a flexible display and the structural design of consumer product involving flexible displays.
P‐124: A 17.3‐inch WQHD Top‐Emission Foldable AMOLED Display with Outstanding Optical Performance and Visual Effects
Authors: Zhang Bing , Qi Puyu , Yang Zhongliu , Lai Zhengde , Wang Zhongjie , Li Suncun , Luo Xuan , Luo Ping , Fan Mengyue , Wang Zhiqiang , Xue Ziliang , Peng Fan , Feng Youxiong
Published: September 2020

A 17.3‐inch WQHD foldable AMOLED display with 10 bit depth was developed. Electrical regulation was carried out to realize high uniformity and contrast ratio. Nearly 100% Adobe and DCI‐P3 coverage revealed its outstanding color expression capacity. De‐mura and IR‐drop compensation IP were integrated to improve visual effects and user experience.
P‐125: Influence of Line Shape on the Durability of Bending Lines on Flexible OLED Panels
Authors: Chen Lin Dou , Peng Tao , Ma Yu Fang , Han Qing , Peng Guanzhen
Published: September 2020

Experiments were conducted to test the durability of bending line with different shapes on the bending area of 5.85 inch flexible OLED panel. Results showed that Z shape lines owned the best performance. Additionally, other shapes were further discussed.
P‐128: High‐SNR Fingerprinting Structure with Switchable Backlight for Liquid‐Crystal Displays
Authors: Huang Kai , Lu Jiangang
Published: September 2020

An optical fingerprinting solution with a switchable backlight is demonstrated for liquid crystal displays (LCDs). In fingerprinting mode, the collimated infrared light is applied to improve the signal‐noise ratio (SNR) between the valley and ridge of the fingerprint. Compare with the conventional backlight, the SNR of the proposed structure can be improved by 84%. Furthermore, the fingerprinting mode and the display mode may work at the same time without interference because of the different wavelength and light path. It shows the great potential application of LCD based optical fingerprint.
P‐130: A Full Screen Biometric Identification Approach for OLED Displays by Using Near‐Infrared OLED
Authors: Lin Chi-Hao , Karim Karim S. , Tai Ya-Hsiang
Published: September 2020

In this paper, we propose a full screen biometric identification approach for organic light emitting diode (OLED) displays using a near infra‐red(NIR) OLED coupled to a large area thin film transistor (TFT) pixel sensing circuit. Preliminary estimates for photons propagating from the NIR OLED source and reflecting back to the subpixel are presented. Although the signal landing on the subpixel is small, it may be amplified by the large area active pixel sensor circuits integrated in the TFT layer. The proposed approach has the key advantage of compatibility with existing large area fabrication processes. Although there are still some open technical issues such as NIR OLED lifetime, responsivity and sensor characteristics, the proposed approach demonstrates the potential to implement a full screen biometric identification within a large area display.
P‐131: A Design of Under‐screen Face Recognition based on Screen Miniature Blind Apertures
Authors: Zhang Hao , Liu Libin , Li Zhenzhen , Zhu Wenxiu , Qian Yuhan , Shi Shiming , Wang Dawei
Published: September 2020

We have successfully produced a display with 0.75mm diameter miniature blind apertures in the display area. The face recognition module is aligned with the bottom of miniature blind apertures. The results show that the face recognition detection range is 25cm to 70cm, the sharpness, contrast and depth precision meet the face recognition requirements. Finally, we realized the face recognition through the screen successfully and achieved the goal of increasing the screen to body ratio.
P‐136: A Low Voltage, Switchable, Bistable‐Twist‐Nematic Display
Authors: Liu Pengcheng , Tseng Man Chun , Yeung Fion Sze Yan , Kwok Hoi Sing
Published: September 2020

The most common electronic paper technology is E‐ink, which enables many novel applications such as e‐readers, watches and electronic shelf labels. However, due to the TFT backplane driving and complex production processes, the cost of this technology is high, which limits its popularity. Recently, a low‐cost π‐bistable twist nematic (π‐BTN) liquid crystal display with a high pretilt angle is proposed. It has the same structure and production method as an ordinary liquid crystal display. Passive driving enables the manufacture of high‐resolution bistable displays without the use of thin‐film transistors. Compared with the current bistable twist nematic display technology, the high pretilt angles structure helps to achieve a low‐voltage and fast‐respond bistable display. This wide viewing angle, high contrast and TFT‐free display is a promising candidate for flexible displays.
P‐137: Developing Fast Bistable FLC Mixtures
Authors: Thurmes William N. , Livingston Michelle , Gabriel Christopher , Pecinovsky Cory , Hathock R. Scott
Published: September 2020

Ferroelectric liquid crystals (FLCs), bistable when used in obliquely‐deposited SiO2 cells, are being developed with the goal of obtaining fast‐switching microdisplays that have about 90% illumination duty cycle. The effects of changing various SiO2 deposition parameters were investigated. A functional bistable FLC dummy cell is demonstrated.
P‐139: Double‐side In‐plane‐switching Electrode Blue‐phase Liquid Crystal Display with Permittivity Protrusion
Authors: Tian Li-Lan , Chu Fan , Li Rui , Gu Xiao-Qing , Zhou Xiang-Xu , Wang Qiong-Hua
Published: September 2020

We propose a transmissive double‐side in‐plane‐switching (IPS) electrodes blue‐phase liquid crystal display (LCD) with permittivity protrusion. The potential drops very slowly in the permittivity protrusions, thus the field penetrating depth is significantly enlarged and the operating voltage is lowered. This device has the advantages of fast response time, easy manufacturing process, and low operation voltage.
P‐141: Color Washout Improvement of VA mode LCDs
Authors: Chen Yani , Wang Jinjie , Zhu Jing , Yong Weina , Zhang Shengdong
Published: September 2020

Herein, we have successfully improved color washout of VA mode TFT‐LCDs by a delicate regulation of LCS and ∆nd. Among them, view angle compensation (VAC) algorithm not only remarkably alleviates color washout and but also facilitates to maintain a high Tr% of 5.6% for LCD panels with 8‐domain pixel structure.
P‐143: A Novel Pixel Structure Design‐MIS (Main In Sub) Pixel
Authors: Qu Kaili , Um Yoonsung , Hao Sikun , Liu Ziqi , Liang Chuwei , Liu Lintao , Li Ting
Published: September 2020

For high‐quality display, a novel pixel structure design‐MIS (main in sub) pixel is proposed. Normal 8‐domain pixel of vertical alignment display is divided into two parts: main‐pixel and sub‐pixel, and these two parts are separated from upper and lower. However, in MIS pixel, main‐pixel is surrounded by sub‐pixel. Through experiments and simulation, we find that the panel with MIS pixel has wider viewing angle, higher liquid crystal efficiency than that with normal pixel.
P‐144: Effects of dielectric anisotropy and electrode structure on the performance of VA‐FFS LC mode
Authors: Choi Wing‐Kit , Hsu Chih‐Wei , Tung Chia‐Hsiang , Tseng Bo‐Kai
Published: September 2020

Vertically‐Aligned Fringe‐Field Switching (VA‐FFS) liquid crystal (LC) mode is known for its intrinsic submillisecond fast response time due to existence of “self‐imposed boundaries” or “virtual walls”. In this paper, we investigate the difference between VA‐FFS LC mode employing LC materials with positive and negative dielectric anisotropy for both 2D and 3D electrode designs. We found that, in general, positive LC materials can provide faster response time whereas negative LC materials can provide higher transmission. In the case of 2D design, negative LC is found to have unexpected slow response times due to i) existence of a 2‐step switching process and ii) disappearance of virtual walls. By using 3D design, both ofthese problems for negative LC have been found to be improved. Due to its fast response time, VA‐FFS LC has been actively researchedfor VR/AR applications in recent years.
P‐145: A New Optical Concept for High Duty Cycle Vertical Alignment Liquid Crystal Displays
Authors: Wu Zirong , Chen Congxin , Zhao Zuzheng
Published: September 2020

Optical film compensated passive matrix vertically aligned liquid crystal displays (PMVA‐LCDs) become more and more popular in many applications such as, industral control, automotive, e‐metering, medical, sports, smart home etc. because of its high contrast ratio and wide viewing angle. However, the current solution of PMVA‐LCD has a shortcoming on its steepness of the transmission‐voltage curve (T‐V curve), which limits its driving duty cycle . Here we demonstrate a new development of a PMVA‐LCD to achieve high duty cycle, up to 1/128, by electro‐optical simulations and experiments.
P‐148: Investigation of photoluminescence and birefringence of nanoparticles dispersed nematic liquid crystal and its application towards liquid crystal display and optoelectronic devices
Authors: Pathak Govind , Prasad Veena , Hegde Gurumurthy
Published: September 2020

In the present investigation nanoparticles (NPs) have been dispersed into the pure nematic liquid crystal (NLC). NPs have been dispersed into the NLC with two different concentrations. Polarizing optical microscope (POD imnages have been recorded for pure NLC and NP dispersed system in the planar aligned liquid crystal cell. The dispersion of NPs in NLC increases the photoluminescence intensity which is an important finding of this study. Birefringence has also been measured here with the help of transmittance technique and it has been observed that the birefringence got increased after the dispersion of NPs into pure NLC. This is the key finding of the present reported work. Relative electric permittivity has also been measured here and found to be increased for the dispersed system as compared to the pure NLC. It is suggested that the output of the present work may be very useful in liquid crystal display and photonic applications.
P‐152: A High Precision and High Contrast Algorithm based on Dual‐cell LCDs
Authors: Xi Yanhui , Sun Yan , Shi Tiankuo , Zhang Xiaomang , Duan Xin , Sun Wei , Chen Ming
Published: September 2020

Local dimming technology can significantly improve the contrast ratio (CR) of LCD products, the more the backlight units, the higher the CR. But due to technical limitations, backlight partitions cannot be made particularly fine. By adding a layer of light control cell between backlight and display panel, the pixel‐level local dimming can be achieved. This paper proposed a high precision and high contrast algorithm based on dual‐cell LCD. The proposed method took pixel shape and position into account which can guarantee two cells matching perfectly and realize low distortion and high contrast display.
P‐154: New Carbon Nanotubes UV Polarizer for Photoalignment of Liquid Crystals
Authors: Shin Hoon Sub , Won Yuri , Manda Ramesh , Jo Mira , Kim Tae Hyung , Lim Young Jin , Lee Seung Hee
Published: September 2020

We propose a unidirectionally aligned multi‐layered carbon nanotubes (CNT) as a UV polarizer for LC photoalignment, which can replace wire‐grid‐polarizer (WGP) with high cost. A 12 multi‐layered CNT polarizer exhibits the degree of polarization up to 91%. The fringe‐field switching (FFS) LC device made by photoalignment with use of the proposed CNT polarizer exhibit uniform LC alignment in whole area and excellent electro‐optics. The work proposes not only cost‐effective novel polarizer replacing WGP for photoalignment of LC but also for photonic component of broadband polarizer from UV to IR.
P‐155: Stabilization of Perovskite Quantum Dots in Polymer Matrix in Thin Porous Film for Display Technology
Authors: Gao Yiyang , Prodanov Maksym F. , Gupta Swadesh K. , Kang Chengbin , Vashchenko Valerii V. , Srivastava Abhishek K.
Published: September 2020

A new hybrid post‐synthetic and in‐film encapsulation method of colloidal perovskite nanoparticles is disclosed. The stabilization of the encapsulated perovskites against oxygen and humidity is tested and discussed. The convenience and scalability of this method opens avenue for perovskites to display application.
P‐160: Curing Mechanism and Optimal Solution for Interior Disclination in Ultrahigh‐definition 2‐domain VA LCD
Authors: Zhang Yinfeng , Cao Wu , Zhang Qi , Zhang Yihe , Huang Zhijun , Lin Yunglun , Xiao Juncheng , Zhang Min
Published: September 2020

Domain reduction design has been proposed to improve the transmittance in the ultrahigh definition display. The inherent confusing concern about the convergence of dark fringe gets completely understood through investigating the vertical alignment procedure. Electric field modulation by terrain and voltage contributes to a favorable LC alignment upon data line BM less structure. Consequently, the interior LC disclination is induced to converge to the inter‐sub‐pixel and the transmittance can be effectively improved.
P‐162: Improvement of Hole Injection in the OLED Devices through Fluorine Plasma
Authors: Lee Eun-Hyung , Jeong Song-Yi , Kim Kwang-Jong , Yoon Sung-Ji , Hwang Soo-Won , Kwon Sun-Kap , Lee Heui-Dong , Baek Ji-Ho , Choi Hyun-Chul , Kang In-Byeong
Published: September 2020

We describe a highly efficient method for improving the hole injection of OLED devices through F plasma treatment. The opto‐electrical property of OLED devices with F treated ITO had nearly identical to conventional OLED devices with p‐doping process. Further, we demonstrate that the migration of F atoms and chemical reaction phenomenon near the interface of HTL improve hole injection and decrease built‐in potential. The OLED devices in this fashion achieve a high reliability and cost‐effectiveness in the various electronic gadgets.
P‐164: Enabling High Performance Organic Light Emitting Diode with Novel Bi‐carbazole Host
Authors: Shahnawaz  , Nagar Mangey Ram , Swayamprabha Sujith Sudheendran , Blaževičius Dovydas , Kručaité Gintaré , Grigalevicius Saulius , Jou Jwo-Huei
Published: September 2020

The high performance of organic light‐emitting diodes (OLEDs) has been achieved with the utilization of the appropriate device architecture engineering and the development of novel materials. The synthesis of the efficient emitter and host materials is the important factor for realizing the higher device efficiency and the ideal performance. Herein, we have introduced a novel bi‐carbazole based host material, which exhibits high energy levels, high mobility, and triplet energy, enhancing the performance of the device. The comparative analysis of the device performance was carried with a different doping concentration of conventional yellow emitter PO‐01 into bi‐carbazole host emitter. As a result, the studied device reveals better performance at 15 wt% doping centration of PO‐01 yellow emitter. The device exhibits good performance as forward‐viewing power efficiency (PE), current efficiency (CE) and external quantum efficiency (EQE) of 19.2 lmW−1, 29.4 cdA−1 and 10.6 %, respectively at 100 cdm−2 brightness with a maximum luminance of 12250 cdm−2. It is also observed that the device shows PE, CE, and EQE of 11.3 lmW−1, 22.7 cdA−1, and 7.5 %, respectively at 1000 cdm−2. The optimal performance could be attributed due to effective host‐to‐guest energy transfer and balanced carrier injection. The results indicate that the development of bi‐carbazole materials may be utilized to maximize the performance of next‐generation lighting applications.
P‐167: UV Light Influence to OLED Filler Encapsulation
Authors: Gao Xinwei , Li Peng , Zang Dandan , Chen Qihe , Yu Donghui , Shih Huai-Ting , Ma Kaihong , Cheng Xuelian , Wu Zhongyuan , Yu Jianwei
Published: September 2020

Organic light‐emitting diodes (OLEDs) have been regarded as one of the most promising technologies for future displays, and efficient encapsidation technology is the key to improve lifetime of OLED devices. Herein, we explore the injitience of different Ultraviolet (UV) lamps (High pressure mercury UV lamp (hereinafter abbreviated as mercury UV lamp) and Light Emitting Diode (LED) UV lamp) on OLED encapsulation filler curing efficiency and probe into the inherent causes. The results show that mercury UV lamp presents a higher filler curing efficiency than LED UV lamp, attributing to its wider light spectrum. Unfortunately, the short wavelength below 325 nm in mercury UV lamp light can cause fast deterioration for filler film. Obviously, this discovery has important guiding effect in optimized design of encapsulation process.
P‐169: Towards Fully Integrated 3D Master Equation — Kinetic Monte Carlo Predictive Device Simulations
Authors: van Mensfoort Siebe , Barbry Marc , Gottardi Stefano , van Eersel Harm
Published: September 2020

In the past decade, the discovery of organic semiconductor materials and the development of organic electronic devices has occurred mostly by experimental trial‐and‐error. In the past years, rational design based on predictive modeling has started playing a larger role in accelerating research and development of organic semiconductor devices. To make this transition possible, we developed and validated advanced predictive simulation software, Bumblebee, based on 3D kinetic Monte Carlo (KMC) and 3D master equation (ME) methods for simulating state‐of‐the art multilayer organic light emitting diode (OLED) stacks. While the 3D‐KMC engine is optimized for high voltages, the 3D‐ME engine is especially suitable for the low voltage regime, making these two engines complementary to each other for efficient simulation of OLED device performance in different operation regimes. To demonstrate the power of predictive modelling, we show several examples of device simulation results obtained with Bumblebee for different OLED stacks. Particular focus will be given to the low current/low voltage range where the impact of traps and energetic disorder on device turn‐on/turn‐off is most important.
P‐170: Green Phosphorescent Organic Light‐Emitting Diodes with Ultra‐thin Undoped Emission Layer of nearly 24% External Quantum Efficiency
Authors: Kang Shin Woo , Ju Byeong-Kwon , Park Young Wook
Published: September 2020

This paper reports the high efficiency green phosphorescent organic light‐emitting diode (OLEDs) with ultra‐thin emission layer structure. The OLEDs were fabricated without conventional and complicated doping process. The optimized OLEDs achieved the maximum external quantum efficiency of nearly 24% without conventional doping process.
P‐175: Machine Learning for Mura Compensation in OLED Applications
Authors: Lin Chia-Hao , Shih Cheng-Kai , Li Yu-Hsuan , Dai Yi-Yo , Shih Li-Wei
Published: September 2020

In this paper, we present a novel Mura compensation technology by using machine learning method to dramatically reduce the DeMura processing time. Using this technology, we had successfully achieved 40% above reduction of DeMura processing time with 3.5” OLED VR display and it still can provide the same DeMura performance.
P‐177: A Novel OLED Pixel Circuit for High‐Resolution or High‐Frequency Application
Authors: Yang Wei-qiang , Qian Xu , Zhai Ying-teng , Gong Hua , He Yue , Jiang Wen-xin
Published: September 2020

This essay proposed a solution for adverse display qualities caused by insufficient charging in fields of high resolution display or high frequency supports. Verified through experiments, results indicate that the modification of the OLED pixel driving circuit could meet the relatively satisfying demands of frequency up to 240Hz@FHD.
P‐184: Distinguished Poster: Coupled 3D Master Equation and 1D Drift‐Diffusion Approach for Advanced OLED Modeling
Authors: Zeder Simon , Kirsch Christoph , Aeberhard Urs , Blülle Balthasar , Jenatsch Sandra , Ruhstaller Beat
Published: September 2020

A hybrid drift‐diffusion (DD) master equation (ME) approach for OLED simulation is established, simultaneously benefiting from the efficiency of the DD approach (charge dynamics) and the physical accuracy of the ME approach (excitonics). We show that such a hybrid model can efficiently describe steady‐state and transient behavior of multilayer OLEDs.
P‐185: Flexible Organic Light‐Emitting Diodes with Improved Outcoupling Efficiency
Authors: Jeong Changyeong , Park Yong-Bum , Guo L. Jay
Published: September 2020

We developed dielectric‐metal‐dielectric (DMD) anode to reduce both rigidity and reflectivity of the film. With optimization of DMD considering adjacent layers used in real devices, we showed that flexible organic light‐emitting diodes (OLEDs) made on DMD can outperform conventional OLEDs made on ITO.
P‐188: Effect of Double‐Layered Bank Structure on Hole‐Injection Properties in Inkjet‐Printed OLED Devices
Authors: Kim Jiyoon , Kim Yool-Guk , Kang Jin-Goo , Lee Chang-Hee
Published: September 2020

We demonstrate hole injection properties of inkjet‐printed organic light emitting diode (OLED) device employing double‐layered bank structure. The double‐layered bank structure consists of the first bank which controls the electric current flowing to the inkjet‐printed organic functional layers and the second bank which separates sub‐pixels and prevents the overflow of dropped ink. In order to verify the charge injection properties in detail, the hole‐only device is fabricated and its electrical response is observed. Our study is helpful in optimizing the double‐layered bank structure which improves the performances of inkjet‐printed OLEDs by modifying the hole injection.
P‐202: High Transmittance Top Conductive Electrodes of OLEDs by Using Conductive Interface Layer
Authors: Liu Yunfei , Zhang Ziyu , Sun Tao , Chen Xiaotian , Ding Tao , Wang Feng , Jing Shu , Wang Tao , Wang Youwei , Qing Chengjie , Zhang Song , Duan Yu
Published: September 2020

We report a conductive interface layer (CIL) in organic light emitting diodes configuration, which may optimize the poor contact between electron injection layers (EILs) and metal cathode. We also fabricated a transparent OLED device with top transparent conductive electrodes (tTCEs) whose transmittance exceeds 80% in both visible and near‐infrared ranges.
P‐227: Late‐News‐Poster: Correlation between External Quantum Efficiency and Electrical Characteristic according to Concentration of Sensitizer in Hyper‐Fluorescent OLEDs
Authors: Lee Hakjun , Hwang Kyo Min , Kim Ki Ju , Kim Young Kwan , Kim Taekyung
Published: September 2020

We analyzed the change of electrical characteristics of hyper‐fluorescence OLED according to the doping concentration using Modulus spectroscopy. As the concentration of the thermally activated delayed fluorescence (TADF) sensitizer increased, the turn‐on voltage was reduced by forming a conductive path by the sensitizer. However, it was not related to the external quantum efficiency (EQE). The difference between the two trends can be understood from the electrical and photophysical perspectives such as Modulus spectroscopy, EL spectrum and capacitance‐voltage (C‐V) curve. The ratio of 5:1 device with the most suitable doping ratio showed the highest 14.86% of EQE and 46.82 cd/A of current efficiency (CE). The reason for this result is that the distance between the sensitizer and the dopant is most suitable considering the Förster energy transfer (FRET) radius. This contributed to the closest match between the point at which the maximum value of capacitance and the turn‐on voltage of the device in the C‐V curve.
P‐233: Late‐News‐Poster: Color Shift Improvement of AMOLED Device with Color Filter
Authors: Zhao Xuan , Huang Jinlei , Wang Zhixiang , Hwang Insun
Published: September 2020

RGB CF structure having different thicknesses is introduced on the TFE, instead of a polarizer, to reduce the total thickness of the flexible display. Through optical simulation, we choose the appropriate RGB CF thicknesses and demonstrate CF array working with optical cavity could effectively improve the color shift with different view angles.
P‐190: Late‐News‐Poster: Micrometer‐scale Patterning of Self‐assembled SWCNT Films and Thin‐Film Transistors Using Patterned PLL Layer
Authors: Park Boik , Jang Jongsu , Kim Hyeonggyu , Seo Jiseok , Yoo Hyunjun , Kim Taehoon , Hong Yongtaek
Published: September 2020

We present micrometer‐scale patterning technologies of PLL layer for solution‐processed SWCNT‐TFTs. Our micrometer‐scale patterning technology allowed for fine feature fabrication down to micrometer‐scale. We also demonstrated the TFTs based on the patterned PLL layer for low‐voltage operation.
Visual tests for elliptically symmetric distributions
Authors: Guha Pritha , Chakraborty Biman
Published: September 2020

We propose a visual test of goodness of fit for families of elliptically symmetric distributions based on a test statistic derived from scale–scale plots. The scale–scale plots are constructed based on the volume functionals of the central rank regions. The test is motivated through the multivariate normal distributions and extended to a test of elliptical symmetry. We derive the asymptotic properties of the test statistic, and we perform detailed power studies for the test of goodness of fit, as well as the test for elliptical symmetry. We also compare the performance of the proposed test with some well‐known alternatives.
Coronaviruses in farm animals: Epidemiology and public health implications
Authors: Khamassi Khbou Médiha , Daaloul Jedidi Monia , Bouaicha Zaafouri Faten , Benzarti M’hammed
Published: September 2020

Coronaviruses (CoVs) are documented in a wide range of animal species, including terrestrial and aquatic, domestic and wild. The geographic distribution of animal CoVs is worldwide and prevalences were reported in several countries across the five continents. The viruses are known to cause mainly gastrointestinal and respiratory diseases with different severity levels. In certain cases, CoV infections are responsible of huge economic losses associated or not to highly public health impact. Despite being enveloped, CoVs are relatively resistant pathogens in the environment. Coronaviruses are characterized by a high mutation and recombination rate, which makes host jumping and cross‐species transmission easy. In fact, increasing contact between different animal species fosters cross‐species transmission, while agriculture intensification, animal trade and herd management are key drivers at the human‐animal interface. If contacts with wild animals are still limited, humans have much more contact with farm animals, during breeding, transport, slaughter and food process, making CoVs a persistent threat to both humans and animals. A global network should be established for the surveillance and monitoring of animal CoVs.
Triangulating Neanderthal cognition: A tale of not seeing the forest for the trees
Authors: Breyl Michael
Published: September 2020

The inference of Neanderthal cognition, including their cultural and linguistic capabilities, has persisted as a fiercely debated research topic for decades. This lack of consensus is substantially based on inherent uncertainties in reconstructing prehistory out of indirect evidence as well as other methodological limitations. Further factors include systemic difficulties within interdisciplinary discourse, data artifacts, historic research biases, and the sheer scope of the relevant research. Given the degrees of freedom in interpretation ensuing from these complications, any attempt to find approximate answers to the yet unsettled pertinent discourse may not rest on single studies, but instead a careful and comprehensive interdisciplinary synthesis of findings. Triangulating Neanderthals' cognition by considering the plethora of data, diverse perspectives and aforementioned complexities present within the literature constitutes the currently most reliable pathway to tentative conclusions. While some uncertainties remain, such an approach paints the picture of an extensive shared humanity between anatomically modern humans and Neanderthals.

This article is categorized under:

Cognitive Biology > Evolutionary Roots of Cognition

Linguistics > Evolution of Language
Catalytic Effect of Green CuO Nanoparticles on the Thermal Decomposition Kinetics of Ammonium Perchlorate
Authors: Benhammada Abdenacer , Trache Djalal , Chelouche Salim , Mezroua Abderrahmane
Published: September 2020

In the present work, a green synthesis of copper oxide nanoparticles (CuO NPs) has been performed through a precipitation method using three different copper precursors and sylvestrys leaf extract as a capping agent. Morphology and structure of the obtained CuO NPs were confirmed by X‐ray diffraction (XRD), ultraviolet‐visible (UV/Vis), Fourier transform infrared (FT‐IR) and Raman spectroscopy, as well as scanning electron microscopy (SEM). Moreover, their thermal behavior and catalytic performance were studied using thermogravimetry (TG) and differential scanning calorimetry (DSC). Four isoconversional kinetic methods have been applied to the DSC data obtained at different heating rates in order to determine the kinetic triplets. The results showed that the introduction of CuO NPs has noticeably lowered the thermal decomposition temperature by 91.7, 89.9, and 83.0 °C, and increased the exothermic enthalpy by 1053, 832, and 962 J·g–1for AP‐CuO‐S, AP‐CuO‐N, and AP‐CuO‐Cl, respectively. Furthermore, CuO NPs were found to reduce the activation energy of AP decomposition. Besides that, ammonium perchlorate decomposes following different reaction models g(α), depending on the decomposition stage and the addition of CuO NPs. These results indicate further that the green synthesized CuO nanoparticles are promising ballistic modifiers for composite solid propellants.
Two-loop beta function for complex scalar electroweak multiplets
Authors: Brod Joachim , Polonsky Zachary
Published: September 2020

Abstract

We present the general form of the renormalizable four-point interactions of a complex scalar field furnishing an irreducible representation of SU(2), and derive a set of algebraic identities that facilitates the calculation of higher-order radiative corrections. As an application, we calculate the two-loop beta function for the SM extended by a scalar multiplet, and provide the result explicitly in terms of the group invariants. Our results include the evolution of the Higgs-portal couplings, as well as scalar “minimal dark matter”. We present numerical results for the two-loop evolution of the various couplings.
The influence of arm composition on the self-assembly of low-functionality telechelic star polymers in dilute solutions
Authors: Moghimi Esmaeel , Chubak Iurii , Founta Dimitra , Ntetsikas Konstantinos , Polymeropoulos George , Hadjichristidis Nikos , Likos Christos N. , Vlassopoulos Dimitris
Published: September 2020

We combine synthesis, physical experiments, and computer simulations to investigate self-assembly patterns of low-functionality telechelic star polymers (TSPs) in dilute solutions. In particular, in this work, we focus on the effect of the arm composition and length on the static and dynamic properties of TSPs, whose terminal blocks are subject to worsening solvent quality upon reducing the temperature. We find two populations, single stars and clusters, that emerge upon worsening the solvent quality of the outer block. For both types of populations, their spatial extent decreases with temperature, with the specific details (such as temperature at which the minimal size is reached) depending on the coupling between inter- and intra-molecular associations as well as their strength. The experimental results are in very good qualitative agreement with coarse-grained simulations, which offer insights into the mechanism of thermoresponsive behavior of this class of materials.
A Unifying Representer Theorem for Inverse Problems and Machine Learning
Authors: Unser Michael
Published: September 2020

Regularization addresses the ill-posedness of the training problem in machine learning or the reconstruction of a signal from a limited number of measurements. The method is applicable whenever the problem is formulated as an optimization task. The standard strategy consists in augmenting the original cost functional by an energy that penalizes solutions with undesirable behavior. The effect of regularization is very well understood when the penalty involves a Hilbertian norm. Another popular configuration is the use of an$$\ell _1$$ℓ1-norm (or some variant thereof) that favors sparse solutions. In this paper, we propose a higher-level formulation of regularization within the context of Banach spaces. We present a general representer theorem that characterizes the solutions of a remarkably broad class of optimization problems. We then use our theorem to retrieve a number of known results in the literature such as the celebrated representer theorem of machine leaning for RKHS, Tikhonov regularization, representer theorems for sparsity promoting functionals, the recovery of spikes, as well as a few new ones.
Geological and Geotechnical Characteristics of London Clay from the Isle of Sheppey
Authors: Bagheri Meghdad , Rezania Mohammad
Published: September 2020

The paper describes a series of experimental testing on natural stiff London clay samples retrieved from the New Hook Farm in the Isle of Sheppey, UK. The experimental program includes determination of macroscopic and microscopic properties, chemical compositions, Atterberg limits, permeability, and compressibility parameters in both intact and reconstituted states. The paper integrates the earlier studies, the new findings, and the commercial investigation results with the aim to extend the current knowledge of the geological and geotechnical characteristics of this stiff clay from the east of the London basin. Some comparisons are also made with shallow depth London clay from Heathrow Terminal 5 site.
Correction to: MongoDB Vs PostgreSQL: a comparative study on performance aspects
Authors: Makris Antonios , Tserpes Konstantinos , Spiliopoulos Giannis , Zissis Dimitrios , Anagnostopoulos Dimosthenis
Published: September 2020

The article “MongoDB Vs PostgreSQL: A comparative study on performance aspects”, written by Antonios Makris, Konstantinos Tserpes, Giannis Spiliopoulos, Dimitrios Zissis, Dimosthenis Anagnostopoulos, was originally published electronically on the publisher’s internet portal on 05 June 2020 without open access.
The Present Shock and Time Re-appropriation in the Pandemic Era
Authors: Levrini Olivia , Fantini Paola , Barelli Eleonora , Branchetti Laura , Satanassi Sara , Tasquier Giulia
Published: September 2020

The crisis due to the COVID-19 pandemic led most people all over the world to deal with a change in their perception and organization of time. This happened also, and mainly, within the educational institutions, where students and teachers had to rearrange their teaching/learning dynamics because of the forced education at a distance. In this paper, we present an exploratory qualitative study with secondary school students aimed to investigate how they were experiencing their learning during lockdown and how, in particular, learning of science contributed to rearranging their daily lifetime rituals. In order to design and carry out our investigation, we borrowed constructs coming from a research field rather unusual for science education: the field of sociology of time. The main result concerns the discovery of the potential of the dichotomy between alienation from time and time re-appropriation. The former is a construct elaborated by the sociologist Hartmut Rosa to describe the society of acceleration in the “era of future shock”. The latter represents an elaboration of the construct of appropriation that the authors had operationally defined, starting from Bakhtin’s original idea, to describe the nexus between physics learning and identity. Thanks to the elaboration of the notion of time re-appropriation as feature of the “era of present shock”, the study unveils how school science, instead of preparing the young to navigate our fast-changing and complex society, tends to create “bubbles of rituals” that detach learning from societal concern.
Mature school cultures and new leadership practices—An analysis of leadership for learning in German comprehensive schools
Authors: Klein Esther Dominique , Bronnert-Härle Hanna
Published: September 2020

In international school improvement research, a long-standing theme is that school improvement is shaped to a great extent by principals and theirleadership for learning. In contrast to that, this role is comparatively new in German-speaking countries. Since the leadership practices associated with this new role differ from old role expectations, it is reasonable to assume that “mature” school cultures might prevent principals from adopting these practices. In this paper, we examine the difference in leadership practice between principals of “mature” and “young” culture schools in socially disadvantaged areas using a standardized teacher survey. The results suggest that while schools with a mature school culture founded during the old principal role were less likely to have such leadership practices that are more proximal to teachers’ instruction and pedagogical practice, this result could largely be explained by other characteristics of the school culture and professional community.
The Influence of Refugee Students’ Personal Characteristics on Study Success in Online Education
Authors: Reinhardt F. , Deribo T. , Zlatkin-Troitschanskaia O. , Happ R. , Nell-Müller S.
Published: September 2020

There is little research on the study success factors of refugee students in higher education. One approach to meeting the growing global demands is to provide online education specifically for refugees. This study examines specific personal characteristics of refugee students and their influence on success and retention in online education. Individual factors such as intrinsic motivation and language proficiency, cognitive functioning, and sociodemographic factors such as gender and country of residence influence retention of refugee students during online studies. The results indicate that sociodemographic factors (e.g., gender), cognitive factors (e.g., English proficiency), and external factors (e.g., country of residence) have a significant influence on study retention on refugee students.
An Integrated Framework for Child Poverty and Well-Being Measurement: Reconciling Theories
Authors: Biggeri Mario , Cuesta Jose Antonio
Published: September 2020

Multidimensional child poverty (MDCP) and well-being measures are increasingly developed in the literature. Much more effort has gone to highlight the differences across measurement approaches than to stress the multiple conceptual and practical similarities across measures. We propose a new framework, the Integrated Framework for Child Poverty—IFCP––that combines three main conceptual approaches, the Capability Approach, Human Rights, and Basic Needs into an integrated bio-ecological framework. This integrated approach aims to bring more clarity about the concept and dynamics of multidimensional poverty and well-being and to disentangle causes from effects, outcomes from opportunities, dynamic from static elements, and observed from assumed behaviours. Moreover, the IFCP explains the MDCP dynamics that link the resources (goods and services), to child capabilities (opportunities) and achieved functionings (outcomes), and describes how these are mediated by the individual, social and environmental conversion factors as specified in the capability approach. Access to safe water is taken as a conceptual illustrative case, while the extended measurement of child poverty and well-being among Egyptian children ages 0 to 5 as an empirical example using IFCP. The proposed framework marks a step forward in understanding child poverty and well-being multidimensional linkages and suggesting desirable features and data requirements of MDCP and well-being measures.
Changes in quantity and quality of organic matter in soil after application of poultry litter and poultry litter biochar—5-year field experiment
Authors: Jarosz Renata , Mierzwa-Hersztek Monika , Gondek Krzysztof , Kopeć Michał , Lošák Tomáš , Marcińska-Mazur Lidia
Published: September 2020

Changes of the addition of poultry litter (PL) and poultry litter biochar (PLB) on quantitative and qualitative humus parameters in loamy sand were estimated during the 5-year study period. The following properties were determined in soil: pH, total carbon (Ctotal), total nitrogen (Ntotal), humic and fulvic acids, extracted carbon, and non-hydrolysing carbon. Additionally, light absorbance in the solutions of humic acids was computed at the wavelength of 280, 465, and 665 nm. It was demonstrated that organic matter mineralisation was most intense in soil with the addition of PL, causing significant quantitative and qualitative changes in humus compounds in soil. A slower rate of organic matter mineralisation was observed in soil amended with PLB, especially in a dose of 5.0 t ha−1, which indicated the long-term effect of this material on improving soil properties. Spectrophotometric indexes for the solution of humic acids also showed that PLB had a more favourable effect on the structure durability and lower mobility of humic acid carbon compared with PL. The application of PL and PLB significantly increased the non-hydrolysing carbon content in soil, indicating greater stabilisation of humus compounds and, at the same time, lower CO2 emissions. It was found that the addition of organic materials to soil significantly increased the soil organic carbon contents. Our study has shown that the identification of changes that may occur in the quantitative and qualitative composition of soil humus after the application of PLB may be helpful in determining the appropriate biochar dose.