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Learning to select the recombination operator for derivative-free optimization

Science China Mathematics 2024年第6期67卷 1457-1480页

作者： Haotian zhang jianyong Sun Thomas Back Zongben Xu School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an710049China Leiden Institute of Advanced Computer Science Leiden UniversityLeiden2333 CANetherlands

Extensive studies on selecting recombination operators adaptively,namely,adaptive operator selection(AOS),during the search process of an evolutionary algorithm(EA),have shown that AOS is promising for improving EA's performance.A variety of heuristic mechanisms for AOS have been proposed in recent decades,which usually contain two main components:the feature extraction and the policy setting.The feature extraction refers to as extracting relevant features from the information collected during the search process.The policy setting means to set a strategy(or policy)on how to select an operator from a pool of operators based on the extracted feature.Both components are designed by hand in existing studies,which may not be efficient for adapting optimization problems.In this paper,a generalized framework is proposed for learning the components of AOS for one of the main streams of EAs,namely,differential evolution(DE).In the framework,the feature extraction is parameterized as a deep neural network(DNN),while a Dirichlet distribution is considered to be the policy.A reinforcement learning method,named policy gradient,is used to train the DNN.As case studies,the proposed framework is applied to two DEs including the classic DE and a recently-proposed DE,which result in two new algorithms named PG-DE and PG-MPEDE,respectively.Experiments on the Congress of Evolutionary Computation(CEC)2018 test suite show that the proposed new algorithms perform significantly better than their counterparts.Finally,we prove theoretically that the considered classic methods are the special cases of the proposed framework.

关键词： evolutionary algorithm differential evolution adaptive operator selection reinforcement learning deep learning

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Extended light absorption and accelerated charge migration in ultrathin twisted carbon nitride nanoplates for efficient solar hydrogen production

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Science China Chemistry 2024年第7期67卷 2215-2223页

作者： Yanmin Zou Shiyao Li Dandan Zheng jianyong Feng Sibo Wang Yidong Hou Guigang zhang State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFuzhou 350108China College of Environment and Safety Engineering Fuzhou UniversityFuzhou 350108China Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State MicrostructuresCollege of Engineering and Applied SciencesNanjing UniversityNanjing 210093China

Polymeric carbon nitride has been widely developed as a promising photocatalyst for solar hydrogen production via photocatalytic water splitting.However,pristine carbon nitride prepared by traditional solid-state polymerization usually encounters issues such as rapid carrier recombination and insufficient absorption of visible light below 460 nm.Herein,poly(heptazine imide)with a distinctive nanoplate structure was synthesized in a binary molten salt of NaCl–CaCl_(2).The salt template allows the formation of the thin nanoplate structure,which promotes the charge separation and migration.Besides,the intercalation of Ca^(2+)ions between the conjugated layers endows the activation of n–π*electron transition due to the distortion of in-plane heptazine layers.Accordingly,the optimized poly(heptazine imide)nanoplates achieve an apparent quantum efficiency of up to 17.3%at 500 nm for photocatalytic hydrogen production from water.This work shares new idea for rational control of the optical absorption and charge carrier dynamics of poly(heptazine imide).

关键词： photocatalysis poly heptazine imide nanoplates ion intercalation hydrogen production

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Efficacy and safety of PD-1 blockade plus long-course chemoradiotherapy in locally advanced rectal cancer(NECTAR):a multi-center phase 2 study

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1721-1729页

作者： Zhengyang Yang Jiale Gao jianyong Zheng Jiagang Han Ang Li Gang Liu Yi Sun Jie zhang Guangyong Chen Rui Xu Xiao zhang Yishan Liu Zhigang Bai Wei Deng Wei He Hongwei Yao Zhongtao zhang Department of General Surgery Beijing Friendship HospitalCapital Medical UniversityState Key Lab of Digestive HealthNational Clinical Research Center for Digestive DiseasesBeijingChina Department of Gastrointestinal Surgery The First Affiliated Hospital of Air Force Medical UniversityXi'anChina Department of General Surgery Beijing Chaoyang HospitalCapital Medical UniversityBeijingChina Department of General Surgery Beijing Xuanwu HospitalCapital Medical UniversityBeijingChina Department of General Surgery Tianjin Medical University General HospitalTianjinChina Department of Anorectal Tianjin People's HospitalTianjinChina Department of Radiology Beijing Friendship Hospital Capital Medical UniversityBeijingChina Department of Pathology Beijing Friendship HospitalCapital Medical UniversityBeijingChina Department of Thoracic Surgery/Institute of Thoracic Oncology West China HospitalSichuan UniversityChengduChina

Adding PD-1 blockade in the neoadjuvant regimens for locally advanced rectal cancer(LARC)patients with microsatellite stable(MsS)/mismatch repair-proficient(pMMR)tumors is an attractive,but debatable strategy.This phase 2,multicenter,prospective,single-arm study enrolled patients from 6 centers from June 2021 to November 2022.Locally advanced rectal cancer(LARC,cT_(3-4a)N_(0)M_(0) and cT_(1-4a)N_(1-2)M_(0))patients aged≥18 years with the distance from distal border of tumor to anal verge≤10 cm(identified by Magnetic Resonance Imaging)were qualifed for inclusion.The patients received long-course radiotherapy(50 Gy/25 fractions,2 Gy/fraction,5 days/week)and three 21-day cycles capecitabine(850-1000 mg/m2,bid,po,day1-14)and three 21-day cycles tislelizumab(200 mg,iv.gtt,day8)as neoadjuvant.Total mesorectal excision(TME)was 6-12 weeks after the end of radiotherapy to achieve radical resection.A total of 50 patients were enrolled in this study.The pathological complete response rate was 40.0%[20/50,95%confidence interval(CI):27.61-53.82%],while 15(30.0%,95%CI:19.1-43.75%),9(18.0%,95%CI:9.77-30.8%),2(4.0%,95%CI:1.10-13.46%)patients respectively achieved grade 1,2,and 3 tumor regression.Treatment-related adverse events(TRAEs)occurred in 28(56.0%)LARC patients,including 26(52.0%)with grade I-II and 2(4.0%)with grade II(1 with grade 3 immune-related colitis and 1 with grade 3 rash).PD-1 blockade plus long-course chemoradiotherapy(CRT)showed promising therapeutic effects according to pathological complete response rate and is well-tolerated in LARC patients.A larger randomized controlled study is desired to further validate the above findings.

关键词： rectal cancer phase

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Calcium carbonate promotes the formation and stability of soil macroaggregates in mining areas of China

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Journal of Integrative Agriculture 2024年第3期23卷 1034-1047页

作者： Junyu Xie jianyong Gao Hanbing Cao Jiahui Li Xiang Wang Jie zhang Huisheng Meng Jianping Hong Tingliang Li Minggang Xu College of Resources and Environment Shanxi Agricultural UniversityTaigu 030801China Shanxi Province Key Laboratory of Soil Environment and Nutrient Resources Taiyuan 030031China College of Land Science and Technology China Agricultural UniversityBeijing 100193China

We studied changes in the concentrations of aggregate-cementing agents after different reclamation times and with different fertilization regimes,as well as the formation mechanism of aggregates in reclaimed soil,to provide a theoretical basis for rapid reclamation of soil fertility in the subsidence area of coal mines in Shanxi Province,China.In this study,soil samples of 0–20 cm depth were collected from four fertilization treatments of a longterm experiment started in 2008:no fertilizer (CK),inorganic fertilizer (NPK),chicken manure compost (M),and50%inorganic fertilizer plus 50%chicken manure compost (MNPK).The concentrations of cementing agents and changes in soil aggregate size distribution and stability were analysed.The results showed that the formation of>2 mm aggregates,the aggregate mean weight diameter (MWD),and the proportion of>0.25 mm water-stable aggregates (WR_(0.25)) increased significantly after 6 and 11 years of reclamation.The concentration of organic cementing agents tended to increase with reclamation time,whereas free iron oxide (Fed) and free aluminium oxide(Ald) concentrations initially increased but then decreased.In general,the MNPK treatment signi?cantly increased the concentrations of organic cementing agents and CaCO_(3),and CaCO_(3) increased by 60.4%at 11 years after reclamation.Additionally,CaCO_(3) had the greatest effect on the stability of aggregates,promoting the formation of>0.25 mm aggregates and accounting for 54.4%of the variance in the proportion and stability of the aggregates.It was concluded that long-term reclamation is bene?cial for improving soil structure.The MNPK treatment was the most effective measure for increasing maize grain yield and concentration of organic cementing agents and CaCO_(3).

关键词： reclamation time manure combined with inorganic fertilizer soil aggregate stability cementing agents CaCO_(3)

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Influence of Mass Ratio of Resin and Stabilizer on Mechanical Properties of Mo Fiber-reinforced Granite Polymer Composite

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 912-920页

作者：张超任秀华 BA Dongzhe zhang Jianhua LI jianyong GUO Mengnan GAO Yinghao WANG Guixin LI Jiayang School of Mechanical and Electronic Engineering Shandong Jianzhu UniversityJinan 250101China Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of Education of ChinaSchool of Mechanical EngineeringShandong UniversityJinan 250061China

Because inferior mechanical strength of granite polymer composite(GPC)has become the main drawback limiting its application and popularization,Mo fibers were added into(GPC)to improve its mechanical strength.Mechanical properties of matrix materials with different mass ratio of resin and stabilizer(MRRS)were investigated systematically.The influences of MRRS on interface bonding strength of Mo fiber-matrix,wettability and mechanical strength of GPC were discussed,respectively,and the theoretical calculation result of MRRS k was obtained,with the optimal value of k=4.When k=4,tensile strength,tensile strain and fracture stress of the cured resin achieve the maximum values.But for k=7,the corresponding values reach the minimum.With the increase of MRRS k,surface free energy of the cured resin first increases and then decreases,while contact angles between Mo sample and matrix have displayed the opposite trend.Wettability of resin to Mo fiber is the best at k=4.Pulling load of Mo fiber and interface bonding strength appear the maximum at k=4,followed by k=5,k=3 the third,and k=7 the minimum.When k=4,mechanical properties of Mo fiber-reinforced GPC are optimal,which is consistent with the result of theoretical calculation.This study is of great significance to get better component formulas of Mo fiber reinforced GPC and to improve its application in machine tools.

关键词： polymer composite fiber mechanical strength interface bonding

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Low Complexity Detection Algorithms Based on ADMIN for Massive MIMO

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China Communications 2023年第11期20卷 67-77页

作者： Shuchao Mi jianyong zhang Fengju Fan Baorui Yan Muguang Wang Institute of Lightwave Technology Beijing Jiaotong UniversityBeijing 100044China Key Lab of All Optical Network and Advanced Telecommunication of EMC Beijing Jiaotong UniversityBeijing 100044China

This paper proposes the alternating direction method of multipliers-based infinity-norm(ADMIN) with threshold(ADMIN-T) and with percentage(ADMIN-P) detection algorithms,which make full use of the distribution of the signal to interference plus noise ratio(SINR) for an uplink massive MIMO system.The ADMIN-T and ADMIN-P detection algorithms are improved visions of the ADMIN detection algorithm,in which an appropriate SINR threshold in the ADMIN-T detection algorithm and a certain percentage in the ADMIN-P detection algorithm are designed to reduce the overall computational complexity.The detected symbols are divided into two parts by the SINR threshold which is based on the cumulative probability density function(CDF) of SINR and a percentage,respectively.The symbols in higher SINR part are detected by MMSE.The interference of these symbols is then cancelled by successive interference cancellation(SIC).Afterwards the remaining symbols with low SINR are iteratively detected by ADMIN.The simulation results show that the ADMIIN-T and the ADMIN-P detection algorithms provide a significant performance gain compared with some recently proposed detection algorithms.In addition,the computational complexity of ADMIN-T and ADMIN-P are significantly reduced.Furthermore,in the case of same number of transceiver antennas,the proposed algorithms have a higher performance compared with the case of asymmetric transceiver antennas.

关键词： ADMIN low complexity detection algo-rithm massive MIMO MMSE SINR

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基于冻融循环试验的改良泥水盾构浆渣劣化特性研究

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现代隧道技术 2024年第1期61卷 260-271页

作者：张建勇中铁十四局集团大盾构工程有限公司南京211899

盾构隧道排放的渣土改性成路基材料可显著提高资源利用效率,但在反复冻融环境下存在安全隐患。依托武汉某盾构隧道工程,以大直径泥水盾构废弃浆渣为研究对象,通过添加自主研发的固废基胶凝剂(Cement-Slag-Gypsum-Alum,CSGA)及玄武岩纤维... 详细信息

盾构隧道排放的渣土改性成路基材料可显著提高资源利用效率,但在反复冻融环境下存在安全隐患。依托武汉某盾构隧道工程,以大直径泥水盾构废弃浆渣为研究对象,通过添加自主研发的固废基胶凝剂(Cement-Slag-Gypsum-Alum,CSGA)及玄武岩纤维(BF)对盾构浆渣进行改良,并对CSGA-BF改良后的盾构浆渣开展冻融循环试验,研究不同纤维掺量、冻融循环次数等条件对改良盾构浆渣的外观劣化特性、力学特性及微观损伤机制的影响。结果表明:在冻融循环作用下,改良浆渣体积呈波浪式变化,并且整体表现为体积膨胀;随着冻融循环次数增加,改良盾构浆渣的无侧限抗压强度及弹性模量均呈现非线性递减,适当掺量的玄武岩纤维可增强筋-土界面的摩擦力,对浆渣的抗冻性具有重要作用,但纤维过量添加也会造成试样强度降低;当冻融循环达到9次后,改良盾构浆渣的抗压强度及弹性模量趋于稳定并且孔隙之间呈现贯通趋势。

关键词：大直径泥水盾构冻融循环废弃浆渣劣化机制

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2022—2023年四川泸定M_(S)6.8、M_(S)5.0和M_(S)5.6地震序列的发震构造及成因

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地球物理学报 2024年第4期67卷 1471-1486页

作者：张建勇王新陈凌刘杰中国地震台网中心北京100045 岩石圈演化国家重点实验室中国科学院地质与地球物理研究所北京100029 中国科学院地球与行星物理重点实验室中国科学院地质与地球物理研究所北京100029 中国科学院大学地球与行星科学学院北京100049

四川泸定2022年9月5日发生M_(S)6.8强震,随后10月22日和2023年1月26日又分别发生M_(S)5.0和M_(S)5.6强余震,主震和两次强余震的震中相距仅几公里却有着截然不同的震源机制解,因此,探究三者的发震构造、联系及成因至关重要.本研究利用国... 详细信息

四川泸定2022年9月5日发生M_(S)6.8强震,随后10月22日和2023年1月26日又分别发生M_(S)5.0和M_(S)5.6强余震,主震和两次强余震的震中相距仅几公里却有着截然不同的震源机制解,因此,探究三者的发震构造、联系及成因至关重要.本研究利用国家地震台网记录到的这三次地震序列的连续波形数据及震相资料进行双差重定位,并进一步采取CAP波形反演方法和P波初动极性反演方法获得研究区M_(L)2.5+的79个余震震源机制解.结果显示,主破裂沿鲜水河断裂磨西段,破裂彻底,余震活动性不高.沿主断裂分布的余震具有明显的分段特征,断层近直立且西北浅东南深.主震及磨西段大部分余震均为走滑机制,是典型的印度—欧亚板块挤压旋转造成鲜水河走滑断裂带应力失稳触发的强震活动.发生在贡嘎山地区的余震是M_(S)6.8主震触发的震群活动,震级水平不高,分布弥散,并没有触发与主断裂共轭的燕子沟、海螺沟和磨子沟次级断裂,而是触发了与主断裂近平行的次级隐伏断裂——贡嘎山断裂.M_(S)5.0和M_(S)5.6两次强余震均发生在该次级隐伏断裂上,断层倾角40°~50°且震源深度较浅.贡嘎山地区拉张型地震活动明显不同于走滑型为主的鲜水河断裂带,可能是印度—欧亚板块挤压旋转作用下贡嘎山快速隆升而地表快速剥离导致局部因重力卸载而垮塌造成的,M_(S)6.8主震有明显的触发作用.三次泸定强震的发生,释放了磨西段及西侧贡嘎山地区部分应力,但并未改变"Y"字形交汇区强震发生的可能性.

关键词：四川泸定地震鲜水河断裂带贡嘎山地区发震构造地震活动性

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Crustal structure study based on principal component analysis of receiver functions

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Science China Earth Sciences 2019年第7期62卷 1110-1124页

作者： jianyong zhang Ling CHEN Xu WANG State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences CAS Center for Excellence in Tibetan Plateau Earth Sciences

The receiver function(RF) technique is an effective method for studying crustal structure. For a single station, the average 1-D crustal structure is usually derived by stacking the radial RFs from all back-azimuths, whereas structural variations(such as dipping discontinuities or anisotropy) can be constrained through analysis of waveform dependence on the backazimuth of both the radial and tangential RFs. However, it is often difficult to directly extract information about structural variations from the waveform of RF, due to the common presence of noise in real data. In this study, we proposed a new method to derive structural variation information for individual stations by applying principal component analysis(PCA) to RFs sorted by back-azimuth. In this method(termed as RF-PCA), a set of principal components(PCs), which are uncorrelated with each other and reflect different characteristics of the RF data, were extracted and utilized separately to reconstruct new RFs. Synthetic tests show that the first PC of the radial RFs contains the average structural information of the crust beneath the corresponding station, and the second PC of the radial RFs and the first PC of the tangential RFs both reflect the variations of the crustal structure. Our synthetic modeling results indicate that the new RF-PCA method is valid for a variety of synthetic models with intra-crustal dipping discontinuities and/or anisotropy. We applied this method to the real data from a broadband temporary seismic station(s233) in the central part of the Sichuan Basin. The results suggest that the RF data can be best explained by the presence of two nearly parallel dipping discontinuities within the crust. Combining with previous logging data, seismic exploration and deep sounding observations, we interpret the shallow dipping discontinuity as the top boundary of the Precambrian crystalline basement of the Sichuan Basin and the deep one corresponding to the Conrad interface between the upper and lower crust, consistent with the geological f

关键词： Principal component analysis Receiver function Crustal structure Dipping discontinuity Anisotropy Sichuan Basin

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From Zeolitic Imidazolate Framework-8 to Metal-Organic Frameworks (MOFs): Representative Substance for the General Study of Pioneering MOF Applications

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Energy & Environmental Materials 2018年第4期1卷 209-220页

作者： Dianting Zou Dingxin Liu jianyong zhang MOE Key Laboratory of Polymeric Composite and Functional Materials School of Materials Science and EngineeringSun Yat-Sen UniversityGuangzhou 510275China

Metal-organic frameworks(MOFs)have been intensely studied for the past few decades as an enormous family of highly tunable porous materials with promisingly applicable functionalities in adsorption,separation,catalysis,sensing,electrochemistry,and a great number of emerging purposes.As a classic MOF,zeolitic imidazolate framework-8(ZIF-8)is conventionally one of the very few MOF members that has been commercialized with considerable production.

关键词： metal-organic frameworks nanoporous composites zeolitic imidazolate frameworks zeolitic imidazolate framework-8

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