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Excitation-Dependent Anti-Thermal Quenching in Zero-Dimensional Manganese Bromides for Photoluminescence and X-Ray Scintillation

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Angewandte Chemie 2024年第5期137卷

作者： Ye Wu Yiyuan Zhu Ashour A. Ahmed Muhammad Imran Shuangchen Qiu Yang Liu Xudong Hu Yasser Hassan Zhiguo Sun Prof. Renren Deng Prof. Xiaoming Li MIIT Key Laboratory of Advanced Display Materials and Devices Institute of Optoelectronics and Nanomaterials College of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China State Key Laboratory of Silicon and Advanced Semiconductor Materials Institute for Composites Science Innovation School of Materials Science and Engineering Zhejiang University Hangzhou 310058 China Leibniz Institute for Catalysis (LIKAT) Albert-Einstein-Str. 29a D-18059 Rostock Germany University of Rostock Institute of Physics Albert-Einstein-Str. 23-24 D-18059 Rostock Germany Department of Electrical and Computer Engineering University of Toronto Toronto Ontario Canada School of Materials Science and Engineering Shenyang University of Technology Shenyang 110870 China Department of Chemistry and Earth Sciences College of Arts and Sciences Qatar University Doha 2713 Qatar School of Chemistry and Chemical Engineering Anshun University Anshun Guizhou 561000 China

One of the most significant challenges of luminescent materials is the thermal quenching (TQ) at high temperature. Understanding the correlation between crystal structure variation and photoluminescence (PL) quenching is significant to achieve anti-thermal quenching (anti-TQ) phosphors. Herein, we unveil a universal principle governing switchable TQ and anti-TQ behaviors in zero-dimensional (0D) organic–inorganic hybrid manganese bromides. We observed an abnormal anti-TQ phenomenon when phosphor is excited in the valley of PL excitation (PLE) spectrum (indirect excitation) while TQ phenomenon is observed when excited in the peak and shoulder positions of PLE. Our findings demonstrate that PL intensity is influenced by two variable parameters: the effective Mn-ligand distance and the shortest Mn−Mn distance. These excitation-dependent TQ and anti-TQ behaviors originate from the relative changes in these distances, which modulate the competition between radiative and nonradiative recombination rates, as evidenced at the molecular level by molecular dynamics simulation. X-ray activated radioluminescence (RL) also exhibits anti-TQ behavior, which is analogous to the indirect excitation of PL evolution when excited at PLE valley. These insights bridge the gap between PL and RL properties in 0D manganese halides and offer potential avenues for developing advanced anti-TQ phosphors, efficient LEDs, and high-performance scintillators.

关键词： anti-thermal quenching manganese bromides excited-state calculation molecular dynamics simulation X-ray scintillators

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Image Foreground Extraction by ICA-PSO and Hilbert-Schmidt Independence Criterion

Image Foreground Extraction by ICA-PSO and Hilbert-Schmidt I...

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International Conference of Signal Processing and Intelligent Systems (ICSPIS)

作者： Hossein Mahdian Toroghi Mitra Mirzarezaee Babak Nadjar Araabi Rahil Mahdian Toroghi Science and Research branch Islamic Azad University Tehran Iran School of Electrical and Computer Engineering College of Engineering University of Tehran Tehran Iran Faculty of Media Technology and Engineering Iran Broadcasting University (IRIBU) Tehran Iran

ISBN: (数字)9781728153506

ISBN: (纸本)9781728153513

Foreground extraction from an image, even by using the reference background is still a challenging problem due to the temporal variations that might occur for the test image, such as background illumination changes and object movements. In this paper, a novel structure has been presented to address this problem using a modified version of ICA algorithm which leverages the Hilbert-Schmidt Independence Criterion (HSIC) instead of the common objective functions. Moreover, the unmixing matrix elements of ICA are extracted through a Particle Swarm (PSO) evolutionary algorithm in a much faster way. The experimental results clearly show the outperformance of the proposed structure over the original works being cited among the references, using Wallflower dataset.

关键词： Signal processing algorithms Kernel Conferences Signal processing Lighting Linear programming Task analysis

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Fluidic fabric muscle sheets for wearable and soft robotics

arXiv

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arXiv 2019年

作者： Zhu, Mengjia Do, Thanh Nho Hawkes, Elliot Visell, Yon Media Arts and Technology Program Department of Electrical and Computer Engineering California NanoSystems Institute Center for Polymers and Organic Solids University of California Santa Barbara United States Graduate School of Biomedical Engineering Faculty of Engineering University of New South Wales Sydney Australia Department of Mechanical Engineering University of California Santa Barbara United States

Conformable robotic systems are attractive for applications in which they can be used to actuate structures with large surface areas, to provide forces through wearable garments, or to realize autonomous robotic systems. We present a new family of soft actuators that we refer to as Fluidic Fabric Muscle Sheets (FFMS). They are composite fabric structures that integrate fluidic transmissions based on arrays of elastic tubes. These sheet-like actuators can strain, squeeze, bend, and conform to hard or soft objects of arbitrary shapes or sizes, including the human body. We show how to design and fabricate FFMS actuators via facile apparel engineering methods, including computerized sewing techniques. Together, these determine the distributions of stresses and strains that can be generated by the FFMS. We present a simple mathematical model that proves effective for predicting their performance. FFMS can operate at frequencies of 5 Hertz or more, achieve engineering strains exceeding 100%, and exert forces greater than 115 times their own weight. They can be safely used in intimate contact with the human body even when delivering stresses exceeding 106 Pascals. We demonstrate their versatility for actuating a variety of bodies or structures, and in configurations that perform multi-axis actuation, including bending and shape change. As we also show, FFMS can be used to exert forces on body tissues for wearable and biomedical applications. We demonstrate several potential use cases, including a miniature steerable robot, a glove for grasp assistance, garments for applying compression to the extremities, and devices for actuating small body regions or tissues via localized skin stretch. Copyright © 2019, The Authors. All rights reserved.

关键词： Elasticity

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For Whom the Games Toll: A Qualitative and Intergenerational Evaluation of What is Serious in Games for Older Adults

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The computer Games Journal 2020年第2期9卷 221-244页

作者： Khalili-Mahani, Najmeh De Schutter, Bob Mirgholami, Mahsa Holowka, Eileen Mary Goodine, Rebecca DeJong, Scott McGaw, Roseleen Meyer, Sue Sawchuk, Kim PERFORM Centre Concordia University Montreal Canada ngAGE Centre for Studies in Aging Concordia University Montreal Canada Technoculture Art & Games Cluster (TAG) Milieux Institute for Art Culture and Technology Concordia University Montreal Canada Armstrong Institute for Interactive Media Studies Miami University Oxford USA Department of Electrical and Computer Engineering Concordia University Montreal Canada Department of Communication Studies Concordia University Montreal Canada Montreal Canada

The aim of this study was to engage older adults in discussions about digital serious games. Using a qualitative exploratory approach, we report observations from more than 100 h of conversations with individuals in the age range 65–90, in a study entitled “Finding better games for older adults” (June 2017–December 2019). Phase 1 (19 older participants, 3 young research students) involved conversations around a quantitative study of cognitive benefits of digital playing (minimum 6 h/person). Phases 2 and 3 involved a focus group in the form of a community class (10 weeks, 2 h per meeting), involving introduction to digital game genres, playing, and discussing motivations and obstacles for current and future play. Cognitive stimulation, emotional distraction and physical therapy were initially stated as the motives for game play. However, with growing familiarity and voluntary exchanges of personal stories between older and younger participants, the cultural significance of the medium of game (especially with story-telling and VR technology) became more important to older adults. More than mechanical inaccessibility, lack of access to the cultural discourse about games presents barriers for older adults. To create a safe, comfortable and accessible space for intergenerational learning and play is of primary importance both for users and designers, should serious games be considered for the future of digital care.

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Progressive cyber-human intelligence for social good

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Interactions 2018年第4期25卷 52-56页

作者： Rikakis, Thanassis Kelliher, Aisling Huang, Jia-Bin Sundaram, Hari Department of Bioengineering Virginia Tech United States Department of Computer Science Institute for Creativity Arts and Technology Virginia Tech United States Bradley Electrical and Computer Engineering Department Virginia Tech United States Computer Science and Advertising Departments University of Illinois at Urbana-Champaign United States

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Automatic classification using DDC on the Swedish union catalogue 18

Automatic classification using DDC on the Swedish union cata...

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18th European Networked Knowledge Organization Systems Workshop, NKOS 2018

作者： Golub, Koraljka Hagelbäck, Johan Ardö, Anders Department of Cultural Sciences Faculty of Arts and Humanities Linnaeus University Växjö Sweden Department of Computer Science and Media Technology Faculty of Technology Linnaeus University Kalmar Sweden Department of Electrical and Information Technology Lund University Lund Sweden

With more and more digital collections of various information resources becoming available, also increasing is the challenge of assigning subject index terms and classes from quality knowledge organization systems. While the ultimate purpose is to understand the value of automatically produced Dewey Decimal Classification (DDC) classes for Swedish digital collections, the paper aims to evaluate the performance of two machine learning algorithms for Swedish catalogue records from the Swedish union catalogue (LIBRIS). The algorithms are tested on the top three hierarchical levels of the DDC. Based on a data set of 143,838 records, evaluation shows that Support Vector Machine with linear kernel outperforms Multinomial Naïve Bayes algorithm. Also, using keywords or combining titles and keywords gives better results than using only titles as input. The class imbalance where many DDC classes only have few records greatly affects classification performance: 81.37% accuracy on the training set is achieved when at least 1,000 records per class are available, and 66.13% when few records on which to train are available. Proposed future research involves an exploration of the intellectual effort put into creating the DDC to further improve the algorithm performance as commonly applied in string matching, and to test the best approach on new digital collections that do not have DDC assigned. © 2018 CEUR-WS. All rights reserved.

关键词： Support vector machines

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Double-port slotted-antenna with multiple miniaturized radiators for wideband wireless communication systems and portable devices

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Progress In Electromagnetics Research C 2019年 90卷 1-13页

作者： Alibakhshikenari, Mohammad Khalily, Mohsen Virdee, Bal Singh Ali, Abdul Shukla, Panchamkumar See, Chan Hwang Abd-Alhameed, Raed A. Falcone, Francisco J. Limiti, Ernesto Electronic Engineering Department University of Rome "Tor Vergata" Via del Politecnico 1 Roma00133 Italy University of Surrey GuildfordGU2 7XH United Kingdom School of Computing and Digital Media Center for Communications Technology London Metropolitan University LondonN7 8DB United Kingdom School of Engineering University of Bolton BoltonBL3 5AB United Kingdom School of Engineering & the Built Environment Edinburgh Napier University Merchiston Campus 10 Colinton Road EdinburghEH10 5DT United Kingdom School of Electrical Engineering and Computer Science University of Bradford BradfordBD7 1DP United Kingdom Electrical and Electronic Engineering Department Public University of Navarre Pamplona31006 Spain

Proof-of-concept is presented of a novel slot antenna structure with two excitation ports. Although this antenna provides a wide impedance bandwidth, its peak gain and optimum radiation efficiency are observed at its mid-band operational frequency. The antenna structure is etched on the top side of a dielectric substrate with a ground plane. The antenna essentially consists of a rectangular patch with two dielectric slots in which multiple coupled patch arms embedded with H-shaped slits are loaded. The two dielectric slots are isolated from each other with a large H-shaped slit. The radiation characteristics of the proposed antenna in terms of impedance bandwidth, gain and efficiency can be significantly improved by simply increasing the number of radiation arms and modifying their dimensions. The antenna’s performance was verified by building and testing three prototype antennas. The final optimized antenna exhibits a fractional bandwidth of 171% (0.5–6.4 GHz) with a peak gain and maximum radiation efficiency of 5.3 dBi and 75% at 4.4 GHz, respectively. The antenna has physical dimensions of 27×37×1.6 mm3 corresponding to electrical size of 0.0452λ0 ×0.0627λ0 ×0.0026λ0,where λ0 is freespace wavelength at 0.5 GHz. The antenna is compatible for integration in handsets and other broadband wireless systems that operate over L-, S-, and C-bands. © 2019, Electromagnetics Academy. All rights reserved.

关键词： Slot antennas

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Intention-based Prediction for Pedestrians and Vehicles in Unstructured Environments 4

Intention-based Prediction for Pedestrians and Vehicles in U...

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4th International Conference on Vehicle technology and Intelligent Transport Systems, VEHITS 2018

作者： Kerscher, Stefan Balbierer, Norbert Kraust, Sebastian Hartmannsgruber, Andreas Müller, Nikolaus Ludwig, Bernd Continental Automotive GmbH Siemensstraße 12 Regensburg Germany Department of Electrical Media and Computer Engineering Deggendorf Institute of Technology Deggendorf Germany Institute of Information and Media Language and Culture University of Regensburg Regensburg Germany

ISBN: (纸本)9789897582936

Motion prediction for holonomic objects in unstructured environments is an ambitious task due to their high freedom of movement compared with non-holonomic objects. In this paper, we present a method for inferring the future goal of holonomic objects by a heuristic generation of target points (tp) and following discriminating decision making. The target points are generated, in a manner that covers the most common motion hypotheses like"following" or"staying", safety relevant motion hypotheses like"crossing future ego trajectories" or the"movement to special points of interest", e.g. gained from a map. Subsequently, for each considered object a trajectory to the inferred target point will be planned. Finally, the uncertainty of the trajectory is estimated by applying a Kalman Filter with a dynamically adjusted process noise matrix. An additional benefit of this concept is its ability to cope with a different quality of context knowledge, so it can produce sound results even at poor structured environments. Copyright © 2018 by SCITEPRESS – Science and technology Publications, Lda. All rights reserved.

关键词： Forecasting

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A multimodal, enveloping soft gripper: Shape conformation, bioinspired adhesion, and expansion-driven suction

arXiv

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arXiv 2019年

作者： Hao, Yufei Biswas, Shantonu Hawkes, Elliot Wang, Tianmiao Zhu, Mengjia Wen, Li Visell, Yon School of Mechanical Engineering and Automation Beihang University Beijing China California NanoSystems Institute University of California Santa BarbaraCA United States Department of Mechanical Engineering University of California Santa BarbaraCA United States Media Arts and Technology Program Department of Electrical and Computer Engineering University of California Santa BarbaraCA United States

—A key challenge in robotics is to create efficient methods for grasping objects with diverse shapes, sizes, poses, and properties. Grasping with hand-like end effectors often requires careful selection of hand orientation and finger placement. Here, we present a soft, fingerless gripper capable of efficiently generating multiple grasping modes. It is based on a soft, cylindrical accordion structure containing coupled, parallel fluidic channels. It is controlled via pressure supplied from a single fluidic port. Inflation opens the gripper orifice for enveloping an object, while deflation allows it to produce grasping forces. The interior is patterned with a gecko-like skin that increases friction, enabling the gripper to lift objects weighing up to 20 N. Our design ensures that fragile objects, such as eggs, can be safely handled, by virtue of a wall buckling mechanism. The gripper can integrate a lip that enables it to form a seal and, upon inflating, to generate suction for lifting objects with flat surfaces. The gripper may also be inflated to expand into an opening or orifice for grasping objects with handles or openings. We describe the design and fabrication of this device and present an analytical model of its behavior when operated from a single fluidic port. In experiments, we demonstrate its ability to grasp diverse objects, and show that its performance is well described by our model. Our findings show how a fingerless soft gripper can efficiently perform a variety of grasping operations. Such devices could improve the ability of robotic systems to meet applications in areas of great economic and societal importance. Copyright © 2019, The Authors. All rights reserved.

关键词： Adhesion

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Accurate machine-learning based modeling of apparent viscosity of waxy oils mixed with polymeric wax inhibitors

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Flow Measurement and Instrumentation 2025年

作者： Hongyan Lei Muntadher Abed Hussein Tarak Vora Anupam Yadav Asha Rajiv Aman Shankhyan Sachin Jaidka Mehul Manu Issa Mohammed Kadhim Zainab Jamal Hamoodah Fadhil Faez Mehrdad Mottaghi College of Computer and Electrical Engineering Hunan University of Arts and Science Changde hunan 415000 China Department of sciecnes Al-Manara College for Medical Sciences (Maysan) Iraq Marwadi University Research Center Department of Civil Engineering Faculty of Engineering & Technology Marwadi University Rajkot-360003 Gujarat India Department of Computer engineering and Application GLA University Mathura-281406 India Department of Physics & Electronics School of Sciences JAIN (Deemed to be University) Bangalore Karnataka India Centre for Research Impact & Outcome Chitkara University Institute of Engineering and Technology Chitkara University Rajpura 140401 Punjab India Department of Physics Department of Applied Sciences Chandigarh Engineering College Chandigarh Group of Colleges-Jhanjeri Mohali 140307 Punjab India Department of Allied Science (Physics) Graphic Era Hill University Bhimtal India Graphic Era Deemed to be University Dehradun Uttarakhand-248002 India Department of Medical Laboratories Technology Al-Nisour University College Nisour Seq. Karkh Baghdad Iraq Mazaya University college An Nasiriyah Dhi Qar Iraq Department of Dentistry College of Dentistry The Islamic University Najaf Iraq Department of medical analysis Medical laboratory technique college the Islamic University of Al Diwaniyah Al Diwaniyah Iraq Department of medical analysis Medical laboratory technique college the Islamic University of Babylon Babylon Iraq Faculty of chemistry Kabul University Kabul Afghanistan

While producing and then transporting waxy oils through pipeline network systems, wax precipitation commonly leads to issues such as wax build-up, gel creation, and decreased flow, negatively affecting pipeline efficiency. To address these problems, the petroleum industry frequently uses polymeric flow improvers to enhance the rheological properties, thereby increasing the mobility and flowability of oils. Experimental methods to measure oil viscosity are both expensive and time-consuming; hence, having reliable data driven frameworks are necessary in this regard. This work presents the use of accurate artificial intelligence methods including K-nearest neighbors, convolutional neural network, multi-layer perceptron artificial neural network, decision tree, support vector machine, adaptive boosting, random forest and ensemble learning to create smart methods for calculating the apparent viscosity of waxy crude oils that are doped with polymeric additives by actual databank sourced from prior studies. A databank containing 526 datapoints was used to both prepare and validate these machine learning algorithms. The predicted results were then evaluated against actual lab data using both graphical and statistical methods. The outcomes showed a strong agreement between the determined and real values for the constructed models. These developed models offer a way of accurate estimation capability bypassing the need for costly, labor-intensive, and time-consuming experimental procedures.

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