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Categorizing methods for integrating machine learning with executable specifications

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science China(Information sciences) 2024年第1期67卷 5-19页

作者： David HAREL Raz YERUSHALMI Assaf MARRON Achiya ELYASAF department of Computer science and applied Mathematics Weizmann Institute of Science department of Software and Information Systems Engineering Ben-Gurion University of the Negev

Deep learning(DL),which includes deep reinforcement learning(DRL),holds great promise for carrying out real-world tasks that human minds seem to cope with quite readily.That promise is already delivering extremely impressive results in a variety of areas.However,while DL-enabled systems achieve excellent performance,they are far from perfect.It has been demonstrated,in several domains,that DL systems can err when they encounter cases they had not hitherto encountered.Furthermore,the opacity of the produced agents makes it difficult to explain their behavior and ensure that they adhere to various requirements posed by human engineers.At the other end of the software development spectrum of methods,behavioral programming(BP) facilitates orderly system development using self-standing executable modules aligned with how humans intuitively describe desired system behavior.In this paper,we elaborate on different approaches for combining DRL with BP and,more generally,machine learning(ML) with executable specifications(ES).We begin by defining a framework for studying the various approaches,which can also be used to study new emerging approaches not covered here.We then briefly review state-of-the-art approaches to integrating ML with ES,continue with a focus on DRL,and then present the merits of integrating ML with BP.We conclude with guidelines on how this categorization can be used in decision making in system development,and outline future research challenges.

关键词： machine learning artificial intelligence grey box learning domain knowledge rules behavioral programming deep reinforcement learning survey

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轻质铝基熵合金:概述与未来趋势（英文）

science China Materials 2024年第1期 31-46页

作者：崔立莹张展陈晓光 Department of Applied Science University of Quebec at Chicoutimi

新一代合金——高熵合金的出现,揭示了熵效应在合金设计中的重要意义.受这一概念的启发,轻质铝基熵合金这一概念被提出.随着对低密度结构材料的需求不断增加,这些新型合金在各种应用中具有巨大的潜力.本文综述了轻质铝基熵合金的发展背...

新一代合金——高熵合金的出现,揭示了熵效应在合金设计中的重要意义.受这一概念的启发,轻质铝基熵合金这一概念被提出.随着对低密度结构材料的需求不断增加,这些新型合金在各种应用中具有巨大的潜力.本文综述了轻质铝基熵合金的发展背景、设计原理、制造方法、微观结构和力学性能、高温应用,及其发展前景.通过对当前研究的全面调查,本文重点研究分析了122种密度低于4.0 g cm-3的铝基熵合金.轻质铝基熵合金可以弥补传统铝和钛合金在机械性能和密度方面的差距.轻质铝基熵合金优异的热稳定性使其有望成为在高温下使用的结构材料.此外,本文还讨论了轻质铝基熵合金领域的未来发展趋势.机器学习作为有效计算工具,可以极大地提高合金的开发效率.

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Magnetically recoverable Fe3O4@polydopamine nanocomposite as an excellent co-catalyst for Fe^3+ reduction in advanced oxidation processes

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Journal of Environmental sciences 2020年第6期32卷 69-78页

作者： Ling Fan Jinliang Xie Zhilin Zhang Yaping Zheng Dongdong Yao Ting Li department of applied Chemistry School of Natural and Applied ScienceNorthwestern Polytechnical UniversityXi'an 710072China

Advanced oxidation processes are widely applied to removal of persistent toxic substances from wastewater by hydroxyl radicals(·OH),which is generated from hydrogen peroxide(H2O2)decomposition.However,their practical applications have been hampered by many strict conditions,such as iron sludge,rigid pH condition,large doses of hydrogen peroxide and Fe^2+,etc.Herein,a magnetically recyclable Fe3O4@polydopamine(Fe3O4@PDA)coreshell nanocomposite was fabricated.As an excellent reducing agent,it can convert Fe^3+to Fe^2+.Combined with the coordination of polydopamine and ferric ions,the production of iron sludge is inhibited.The minimum concentration of hydrogen peroxide(0.2 mmol/L and Fe^2+(0.18 mmol/L))is 150-fold and 100-fold lower than that of previous reports,respectively.It also exhibits excellent degradation performance over a wide pH range from 3.0 to 9.0.Even after the tenth recycling,it still achieves over 99%degradation efficiency with the total organic carbon degradation rate of 80%,which is environmentally benign and has a large economic advantage.This discovery paves a way for extensive practical application of advanced oxidation processes,especially in environmental remediation.

关键词： Fe3O4@polydopamine nanocomposites Fenton-like catalysts Fe^3+/Fe^2+cycle Magnetically reusable

Optimizing Cr^(3+) concentration and evaluating energy transfer from Cr^(3+) to Nd^(3+) in Cr,Nd:GGG nanocrystals prepared by sol-gel method

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Journal of Rare Earths 2016年第11期34卷 1077-1082页

作者： Yassin Alshikh Mohamad Yomen Atassi Zafer Moussa department of applied Physics Higher Institute for Applied Science and Technology

Nanopowder of Cr：GGG and nanopowder of Cr,Nd：GGG with different concentrations of Cr3＋ ranging from 0.1 at.% to 1.5 at.% were synthesized by the sol-gel method using acetic acid and ethylene glycol. Thermal gravimetric analysis and differential scanning calorimetry （TGA-DSC）, X-ray diffraction （XRD） and photoluminescence spectroscopy were used to characterize the powder. The crystallite size was about 58 nm when treated at 1000 oC for 2 h. Cr3＋ photoluminescence spectrum in GGG showed a broad band emission around 730 nm. The intensity of this band decreased when co-doped with Nd, indicating an efficient energy transfer from Cr3＋ to Nd3＋. Photoluminescence intensity of Nd in Cr,Nd：GGG at 1.06μm showed that the optimum concentration of Cr3＋ was about 1 at.% （more or less） for 1 at.% Nd3＋. This result was also confirmed by chromium fluorescence decay rate analysis. Energy transfer efficiency was found to be about 84% for 1 at.% concentration of each chromium and neodymium.

关键词： nanopowder Cr,Nd：GGG sol-gel fluorescence lifetime energy transfer efficiency rare earths

Quantitative determination of erlotinib in human serum using competitive enzyme-linked immunosorbent assay

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Journal of Pharmaceutical Analysis 2018年第2期8卷 119-123页

作者： Yuta Yamamoto Tetsuya Saita Yutaro Yamamoto Masashi Shin applied Life science department Faculty of Biotechnology and Life Science Sojo University

A selective and sensitive competitive enzyme-linked immunosorbent assay(ELISA) method was developed and validated for the quantification of erlotinib in 50 mL of samples of human serum. Anti-erlotinib serum was obtained by immunizing mice with an antigen conjugated with bovine serum albumin and 3,4-bis(2-methoxyethoxy)benzoic acid using the N-succinimidyl ester method. Enzyme labeling of erlotinib with horseradish peroxidase was similarly performed using 3,4-bis(2-methoxyethoxy)benzoic acid. A simple competitive ELISA for erlotinib was developed using the principle of direct competition between erlotinib and the enzyme marker for anti-erlotinib antibody, which had been immobilized on the plastic surface of a microtiter plate. Serum erlotinib concentrations lower than 40 ng/mL were reproducibly measurable using the ELISA. This ELISA was specific to erlotinib and showed very slight cross-reactivity(6.7%) with a major metabolite, O-desmethyl erlotinib. Using this assay, drug levels were easily measured in the blood of mice after oral administration of erlotinib at a single dose of 30 mg/kg. ELISA should be used as a valuable tool for therapeutic drug monitoring and in pharmacokinetic studies of erlotinib.

关键词： Erlotinib Enzyme-linked immunosorbent assay O-desmethyl erlotinib Tyrosine-kinase inhibitor

Bald Eagle Search Optimization Algorithm Combined with Spherical Random Shrinkage Mechanism and Its Application

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Journal of Bionic Engineering 2024年第1期21卷 572-605页

作者： Wenyan Guo Zhuolin Hou Fang Dai Xiaoxia Wang Yufan Qiang department of applied Mathematics School of ScienceXi'an University of TechnologyXian 710054ShaanxiChina

Over the last two decades,stochastic optimization algorithms have proved to be a very promising approach to solving a variety of complex optimization problems.Bald eagle search optimization(BES)as a new stochastic optimization algorithm with fast convergence speed has the ability of prominent optimization and the defect of collapsing in the local best.To avoid BES collapse at local optima,inspired by the fact that the volume of the sphere is the largest when the surface area is certain,an improved bald eagle search optimization algorithm(INMBES)integrating the random shrinkage mechanism of the sphere is proposed.Firstly,the INMBES embeds spherical coordinates to design a more accurate parameter update method to modify the coverage and dispersion of the population.Secondly,the population splits into elite and non-elite groups and the Bernoulli chaos is applied to elite group to tap around potential solutions of the INMBES.The non-elite group is redistributed again and the Nelder-Mead simplex strategy is applied to each group to accelerate the evolution of the worst individual and the convergence process of the INMBES.The results of Friedman and Wilcoxon rank sum tests of CEC2017 in 10,30,50,and 100 dimensions numerical optimization confirm that the INMBES has superior performance in convergence accuracy and avoiding falling into local optimization compared with other potential improved algorithms but inferior to the champion algorithm and ranking third.The three engineering constraint optimization problems and 26 real world problems and the problem of extracting the best feature subset by encapsulated feature selection method verify that the INMBES’s performance ranks first and has achieved satisfactory accuracy in solving practical problems.

关键词： Bald eagle search optimization algorithm Spherical coordinates Chaotic variation Simplex method Encapsulated feature selection

Effect of dopant concentration on the spectra characteristic in Zr^(4+) doped Yb:Nd:LiNbO_3 crystals

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Journal of Rare Earths 2017年第8期35卷 761-766页

作者：代丽刘春蕊闫哲华韩县博王路平谭超徐玉恒 applied science College Harbin University of Science and Technology department of the applied Chemistry Harbin Institute of Technology

A series of Yb：Nd：LiNbO3 crystals tridoped with various concentrations of Zr4＋（1 mol.%, 2 mol.% and 4 mol.%） were grown by the Czochralski technique from the congruent melt. The X-ray powder diffraction, UV-Vis-NIR absorption spectra and IR transmittance spectra were measured to analyze the crystal composition and defect structure. The Zr4＋, Yb3＋ and Nd3＋ ions in LiNbO3 crystal had two effects： volume compensation effect and ion valence state compensation effect. The Zr O2 doping threshold concentration was nearly 2.0 mol.%. The fluorescence emissions of Nd3＋ ions and Yb3＋ ions were observed under 808 nm excitation. The intensity of fluorescence emissions enhanced with the increasing of the Zr4＋ doping concentrations. The Zr：Yb：Nd：LiNbO3 crystals with 4 mol.% doping concentration of Zr4＋ ion revealed strong emission around 1 μm, which is of great significance for laser materials.

关键词： Zr：Yb：Nd：LiNbO3 crystals UV-Vis-NIR dopant concentration rare earths

Optical properties of Mg^(2+),Yb^(3+),and Ho^(3+) tri-doped LiNbO_3 crystals

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Chinese Physics B 2017年第4期26卷 225-230页

作者：代丽刘春蕊谭超阎哲华徐玉恒 applied science College Harbin University of Science and Technology department of applied Chemistry Harbin Institute of Technology

A series of LiNbO_3 crystals tri-doped with Mg^（2＋）,Yb^（3＋）,and Ho^（3＋） are grown by the conventional Czochraski technique.The concentrations of Mg^（2＋）,Yb^（3＋）,and Ho^（3＋） ions in Mg：Yb：Ho：LiNbO_3 crystals are measured by using an inductively coupled plasma atomic emission spectrometry.The x-ray diffraction is proposed to determine the lattice constant and analyze the internal structure of the crystal.The light-induced scattering of Mg：Yb：Ho：LiNbO_3 crystal is quantitatively described via the threshold effect of incident exposure energy flux.The exposure energy（E_r） is calculated to discuss the optical damage resistance ability.The exposure energy of Mg（7 mol）：Yb：Ho：LiNbO3 crystal is 709.17 J/cm^2,approximately 425 times higher than that of the Mg（l mol）：Yb：Ho：LiNbO_3 crystal in magnitude.The blue,red,and very intense green bands of Mg：Yb：Ho：LiNbO_3 crystal are observed under the 980-nm laser excitation to evaluate the up-conversion emission properties.The dependence of the emission intensity on pumping power indicates that the up-conversion emission is a two-photon process.The up-conversion emission mechanism is discussed in detail.This study indicates that Mg：Yb：Ho：LiNbO_3 crystal can be applied to the fabrication of new multifunctional photoluminescence devices.

关键词： crystal growth optical properties x-ray diffraction crystal structure

Investigation on nonlinear multi-scale effects of unsteady flow in hydraulic fractured horizontal shale gas wells

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applied Mathematics and Mechanics(English Edition) 2018年第2期39卷 181-192页

作者： Jiaxuan LIU Xinchun SHANG Weiyao ZHU department of applied Mechanics University of Science and Technology Beijing Institute of applied Mechanics University of Science and Technology Beijing

A unified mathematical model is established to simulate the nonlinear unsteady percolation of shale gas with the consideration of the nonlinear multi-scale effects such as slippage, diffusion, and desorption. The continuous inhomogeneous models of equivalent porosity and permeability are proposed for the whole shale gas reservoir includ- ing the hydraulic fracture, the micro-fracture, and the matrix regions. The corresponding semi-analytical method is developed by transforming the nonlinear partial differential governing equation into the integral equation and the numerical discretization. The nonlinear multi-scale effects of slippage and diffusion and the pressure dependent effect of desorption on the shale gas production are investigated.

关键词： shale gas nonlinear effect multi-scale percolation inhomogeneous perme ability integral equation