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Optimal Shape Factor and Fictitious Radius in the MQ-RBF:Solving Ill-Posed Laplacian Problems

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3189-3208页

作者： Chein-Shan Liu chung-Lun kuo Chih-wen Chang Center of Excellence for Ocean Engineering Taiwan Ocean UniversityKeelung202301TaiwanChina Department of Mechanical Engineering National United UniversityMiaoli36063TaiwanChina

To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection technique is developed to identify the optimal shape factor and fictitious radius by minimizing a merit function.A sample function is interpolated by theMQ-RBF to provide a trial coefficient vector to compute the merit *** can quickly determine the optimal values of the parameters within a preferred rage using the golden section search *** novel method provides the optimal values of parameters and,hence,an optimal MQ-RBF;the performance of the method is validated in numerical ***,nonharmonic problems are transformed to the Poisson equation endowed with a homogeneous boundary condition;this can overcome the problem of these problems being *** optimal MQ-RBF is extremely *** further propose a novel optimal polynomial method to solve the nonharmonic problems,which achieves high precision up to an order of 10^(−11).

关键词： Laplace equation nonharmonic boundary value problem Ill-posed problem maximal projection optimal shape factor and fictitious radius optimal MQ-RBF optimal polynomial method

Highly Accurate Golden Section Search Algorithms and Fictitious Time Integration Method for Solving Nonlinear Eigenvalue Problems

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1317-1335页

作者： Chein-Shan Liu Jian-Hung Shen chung-Lun kuo Yung-Wei Chen Center of Excellence for Ocean Engineering Taiwan Ocean UniversityKeelung202301TaiwanChina Department of Marine Engineering Taiwan Ocean UniversityKeelung202301TaiwanChina

This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue *** each eigen-parameter the vector variable is solved from a nonhomogeneous linear system obtained by reducing the number of eigen-equation one less,where one of the nonzero components of the eigenvector is normalized to the unit and moves the column containing that component to the right-hand side as a nonzero input vector.1D and 2D golden section search algorithms are employed to minimize the merit functions to locate real and complex ***,the real and complex eigenvectors can be computed very accurately.A simpler approach to the nonlinear eigenvalue problems is proposed,which implements a normalization condition for the uniqueness of the eigenvector into the eigenequation *** real eigenvalues can be computed by the fictitious time integration method(FTIM),which saves computational costs compared to the one-dimensional golden section search algorithm(1D GSSA).The simpler method is also combined with the Newton iterationmethod,which is convergent very *** the proposed methods are easily programmed to compute the eigenvalue and eigenvector with high accuracy and efficiency.

关键词： Nonlinear eigenvalue problem quadratic eigenvalue problem two new merit functions golden section search algorithm fictitious time integration method

Flexible nanoimprint lithography enables high-throughput manufacturing of bioinspired microstructures on warped substrates for efficient III-nitride optoelectronic devices

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Science Bulletin 2024年第13期69卷 2080-2088页

作者： Siyuan Cui Ke Sun Zhefu Liao Qianxi Zhou Leonard Jin Conglong Jin Jiahui Hu kuo-Sheng wen Sheng Liu Shengjun Zhou Center for Photonics and Semiconductors School of Power and Mechanical EngineeringWuhan UniversityWuhan 430072China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China Department of Mechanical and Mechatronics Engineering University of WaterlooWaterloo ONN2L 3G1Canada Jiangxi SMTC Semiconductor Co. Ltd.Nanchang 330096China

III-nitride materials are of great importance in the development of modern optoelectronics,but they have been limited over years by low light utilization rate and high dislocation densities in heteroepitaxial films grown on foreign substrate with limited refractive index contrast and large lattice ***,we demonstrate a paradigm of high-throughput manufacturing bioinspired microstructures on warped substrates by flexible nanoimprint lithography for promoting the light extraction *** design a flexible nanoimprinting mold of copolymer and a two-step etching process that enable high-efficiency fabrication of nanoimprinted compound-eye-like Al2O3 microstructure(NCAM)and nanoimprinted compound-eye-like SiO_(2)microstructure(NCSM)template,achieving a 6.4-fold increase in throughput and 25%savings in economic costs over stepper projection *** to NCAM template,we find that the NCSM template can not only improve the light extraction capability,but also modulate the morphology of AlN nucleation layer and reduce the formation of misoriented GaN grains on the inclined sidewall of microstructures,which suppresses the dislocations generated during coalescence,resulting in 40%reduction in dislocation *** study provides a low-cost,high-quality,and high-throughput solution for manufacturing microstructures on warped surfaces of III-nitride optoelectronic devices.

关键词： Flexible nanoimprint lithography Bioinspired Micro-and nano-manufacturing III-nitride epitaxy Optoelectronic devices

Self-polarized RGB device realized by semipolar micro-LEDs and perovskite-in-polymer films for backlight applications

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Opto-Electronic Advances 2024年第3期7卷 35-49页

作者： Tingwei Lu Yue Lin Tianqi Zhang Yue Huang Xiaotong Fan Shouqiang Lai Yijun Lu Hao-chung kuo Zhong Chen Tingzhu Wu Rong Zhang School of Electronic Science and Engineering Fujian Engineering Research Center for Solid-State LightingXiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China Department of Photonics and Graduate Institute of Electro-Optical Engineering College of Electrical and Computer EngineeringYang Ming Chiao Tung UniversityHsinchu 30010China Semiconductor Research Center Hon Hai Research InstituteTaipei 11492China.

In backlighting systems for liquid crystal displays,conventional red,green,and blue(RGB)light sources that lack polarization properties can result in a significant optical loss of up to 50%when passing through a *** address this inefficiency and optimize energy utilization,this study presents a high-performance device designed for RGB polarized *** device employs an array of semipolar blueμLEDs with inherent polarization capabilities,coupled with mechanically stretched films of green-emitting CsPbBr3 nanorods and red-emitting CsPbI3-Cs4PbI6 hybrid *** CsPbBr3 nanorods in the polymer film offer intrinsic polarization emission,while the aligned-wire structures formed by the stable CsPbI3-Cs4PbI6 hybrid nanocrystals contribute to substantial anisotropic emissions,due to their high dielectric *** resulting device achieved RGB polarization degrees of 0.26,0.48,and 0.38,respectively,and exhibited a broad color gamut,reaching 137.2%of the NTSC standard and 102.5%of the Rec.2020 *** compared to a device utilizing c-plane LEDs for excitation,the current approach increased the intensity of light transmitted through the polarizer by 73.6%.This novel fabrication approach for polarized devices containing RGB components holds considerable promise for advancing next-generation display technologies.

关键词： halide perovskite light-emitting-diodes polarized emission nanocrystals stability

维普期刊数据库

Ten- year follow- up investigation of stroke risk in systemic lupus erythematosus

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Stroke & Vascular Neurology 2024年第1期9卷 1-7页

作者： Jin-An Huang Ching-Heng Lin Ming-Ju Wu Yi-Hsing Chen kuo-Cheng Chang chung-Wei Hou Division of Neurology Neurological InstituteTaichung Veterans General HospitalTaichungTaiwan Department of Health Business Administration Hungkuang UniversityTaichungTaiwan Department of Medical Research Taichung Veterans General HospitalTaichungTaiwan Division of Nephrology Department of Internal MedicineTaichung Veterans General HospitalTaichungTaiwan School of Medicine Chung Shan Medical UniversityTaichungTaiwan College of Medicine National Chung Hsing UniversityTaichungTaiwan Division of Allergy Immunology and RheumatologyDepartment of Internal MedicineTaichung Veterans General HospitalTaichungTaiwan School of Medicine National Yang-Ming Chiao Tung UniversityTaichungTaiwan

Background and purpose To analyse the long-term risk of ischaemic stroke and the clinical effects of antithrombotics on the risk of haemorrhagic stroke in patients with systemic lupus erythematosus(SLE).Methods A retrospective cohort study was conducted using a population-based database taken from Taiwan National Health Insurance Research *** with SLE between 2000 and 2008 were registered and matched with two controls by the index date,age,gender and Charlson Comorbidity Index(CCI).These subjects were followed until either stroke event or 31 December *** HRs(aHRs)for strokes were estimated with Cox regression models,and the cumulative incidence of ischaemic stroke was analysed by log-rank test and Kaplan-Meier survival *** In total,8310 patients with SLE and 16620 patients without SLE were *** general,patients with SLE had higher rates of ischaemic stroke(5.4%vs 3.3%)and haemorrhagic stroke(1.5%vs 0.6%)than in *** multivariate analysis adjusted to age,gender,CCI,urbanisation level and antithrombotics uses,aHRs of all strokes,ischaemic stroke and haemorrhagic stroke were 1.73(95%CI:1.54 to 1.94),1.65(95%CI:1.45 to 1.87)and 2.24(95%CI:1.71 to 2.95),respectively,in patients with *** with SLE were significantly more likely to suffer ischaemic stroke than patients without SLE,even 10 years after SLE diagnosis(6.12%vs 3.50%,p<0.001).Antiplatelet use increased the risk of haemorrhagic stroke in SLE group(aHR=1.74,95%CI:1.18 to 2.57).Conclusions Patients with SLE are at greater risk of developing ischaemic stroke that lasts for 10 *** should be carefully administered to prevent cardiovascular events in patients with SLE due to the risk of haemorrhagic stroke.

关键词： erythematosus diagnosis likely

Constrained reinforcement learning with statewise projection: a control barrier function approach

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Science China(Information Sciences) 2024年第3期67卷 136-154页

作者： Xinze JIN kuo LI Qingshan JIA Department of Automation Tsinghua University

Safety is a critical issue for reinforcement learning(RL), as it may be risky for some actual applications if the learning process involves unsafe exploration. Instead of formulating constraints as expectationbased in constrained RL, considering statewise safety in constrained RL is more meaningful. This work aims to address the issue of safe projection in RL by introducing a control barrier function that inherently learns a safe policy through a set certificate. We seek to analyze some theoretical properties of safe projection in the learning process, including convergence and performance bound, and extend the discussion into ensembles and guided controllers. Moreover, we approach analytical solutions for deterministic and stochastic system dynamics. Experimental results in different tasks show that the proposed method achieves better effects in terms of both performance and safety.

关键词： reinforcement learning safe projection control barrier function

Research progress and prospect of low-carbon biological technology for nitrate removal in wastewater treatment

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 1-21页

作者： Ru Zheng kuo Zhang Lingrui Kong Sitong Liu College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China Key Laboratory of Water and Sediment Sciences Ministry of Education of ChinaBeijing 100871China Eco-Environment and Resource Efficiency Research Laboratory School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China

Wastewater treatment plants are the major energy consumers and significant sources of greenhouse gas emissions,among which biological nitrogen removal of wastewater is an important contributor to carbon ***,traditional heterotrophic denitrification still has the problems of excessive residual sludge and the requirement of external carbon ***,the development of innovative low-carbon nitrate removal technologies is *** review outlines the key roles of sulfur autotrophic denitrification and hydrogen autotrophic denitrification in low-carbon wastewater *** discovered nitrate/nitrite dependent anaerobic methane oxidation enables sustainable methane emission reduction and nitrogen removal by utilizing available methane in *** microorganisms exhibited a promising potential to achieve carbon-negative nitrate ***,the algal-bacterial symbiosis system and photogranules offer effective and prospective low-carbon options for nitrogen ***,the emerging nitrate removal technology of photoelectrotrophic denitrification and the underlying,photoelectron transfer mechanisms are ***,we summarize and prospect these technologies,highlighting that solar-driven biological nitrogen removal technology is a promising area for future sustainable wastewater *** review has important guiding significance for the design of low-carbon wastewater treatment systems.

关键词： Carbon emissions Low-carbon Biological nitrogen removal Denitrification

Reversible JPEG Data Hiding Based on EMD

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通讯和计算机（中英文版） 2012年第10期9卷 1135-1141页

作者： wen-chung kuo Shao-Hung kuo Department of Computer Science and Information Engineering National Yunlin University of Science & Technology Yunlin 672 Taiwan Graduate School of Engineering Science and Technology Doctoral Program National Yunlin University of Science and Technology Yunlin 640 Taiwan

As the rapid growth of smart phone technology, people have a lot of digital image information such as digital photos or videos. Both data hiding and data compression are very important technologies in image processing field. On the overview, it seems that there is no relationship between data hiding and data compression because data hiding mechanisms focus on information security and data compression mechanisms emphasize the compression ratio. However, the more secret data is embedded, the more capacity the stego image increases. Actually, they are closely related. Until now, there are many literatures to discuss the secret data how to be embedded into the media image and keeps the original capacity as soon as possible. In this paper, a reversible data hiding scheme based on EMD data hiding and JPEG (Joint Picture Experts Group) compression technology will be proposed. According to experimental results, the authors can prove that our proposed scheme maintains high embedding capacity, security and good compression ratio.

关键词：数据隐藏 JPEG EMD 可逆数字图像信息数据嵌入压缩技术数据压缩

Converting an O-vacancy-rich oxide into a multifunctional separator modifier for long-lifespan lithium metal batteries

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Journal of Energy Chemistry 2024年第10期97卷 371-378页

作者： Juntao Si Xiaoying Li Yixuan Li kuo Cao Yiran Zhu Chunhua Chen CAS Key Laboratory of Precision and Intelligent Chemistry Department of Materials Science and Engineering University of Science and Technology of China

The lithium metal anode is hailed as the desired "holy grail" for the forthcoming generation of highenergy-density batteries,given its astounding theoretical capacity and low ***,the formation and growth of dendrites seriously compromise battery life and ***,an yttriastabilized bismuth oxide（YSB） layer is fabricated on the polypropylene（PP） separator,where YSB reacts with Li anode in-situ in the cell to form a multi-component composite interlayer consisting of Li3Bi,Li2O,and *** interlayer can function not only as a redistributor to regulate Li+distribution but also as an anion adsorber to increase the Li+transference number from 0.37 to 0.79 for suppressing dendrite nucleation and ***,compared with the cell with a baseline separator,those with modified separators exhibit prolonged lifespan in both Li/Li symmetrical cells and Li/Cu ***,the full cells coupled with ultrahigh-loading LiFePO4display an excellent cycling performance of 1700 cycles with a high capacity retention of ～80% at 1 C,exhibiting great potential for practical *** work provides a feasible and effective new strategy for separator modification towards building a much-anticipated dendrite-free Li anode and realizing long-lifespan lithium metal batteries.

关键词： Conversion-alloying reaction Dendrite-free Lithium metal battery Multifunctional interlayer Separator