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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 191-200页

作者： LI zhi-yu LI Kun CAI Jin-ming QIN Jian-fang ZHENG Zhao-wen School of Mathematical Sciences Qufu Normal UniversityQufu 273165China College of Mathematics and Systems Science Guangdong Polytechnic Normal UniversityGuangzhou 510665China

A class of Sturm-Liouville problems with discontinuity is studied in this paper.The oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are obtained.The main method used in this paper is based on Prufer transformation,which is different from the classical ones.Moreover,we give two examples to verify our main results.

关键词： Sturm-Liouville problem interface condition oscillatory solution

Flexible tuning of multifocal holographic imaging based on electronically controlled metasurfaces

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Photonics Research 2024年第1期12卷 61-69页

作者： Owen ZENG CHENXIA LI BO fang zhi HONG XUFENG JING Institute of Optoelectronic Technology China Jiliang UniversityHangzhou 310018China Centre for THz Research China Jiliang UniversityHangzhou 310018China College of Metrology&Measurement Engineering China Jiliang UniversityHangzhou 310018China

Programmable hyper-coded holography has the advantage of being programmable as well as being flexibly modifiable.Digitally coded metamaterials with excellent electromagnetic modulation capability and the ability to control the phase to modulate the spatial radiation field through external excitation in the form of switching can be used to realize low-cost digital arrays.We design a 1-bit encoded programmable metasurface,which is electrically connected to control the PIN diode in the switching state and to switch the condition of each metasurface cell between“0”and“1.”Using the designed programmable metasurface,we can randomly encode the cell structure to realize single-focus focusing,multi-focusing,and simple holographic letter imaging.Based on the nonlinear holographic model,we employ the Gerchberg-Saxton improvement algorithm to modulate the energy distribution at the focus by adjusting the phase distribution.Importantly,we introduce the Fourier convolution principle to regulate the holographic imaging focus flexibly.

关键词： holographic letter excitation

Monte Carlo Simulation-Based Robust Workflow Scheduling for Spot Instances in Cloud Environments

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Tsinghua Science and Technology 2024年第1期29卷 112-126页

作者： Quanwang Wu Jianzhao fang Jie Zeng Junhao wen Fengji Luo College of Computer Science Chongqing UniversityChongqing 400044China National Experimental Teaching Demonstration Center Chongqing UniversityChongqing 400044China College of Big Data and Software Engineering Chongqing UniversityChongqing 400044China School of Civil Engineering The University of SydneySydney 2006Australia

When deploying workflows in cloud environments,the use of Spot Instances(SIs)is intriguing as they are much cheaper than on-demand ones.However,Sls are volatile and may be revoked at any time,which results in a more challenging scheduling problem involving execution interruption and hence hinders the successful handling of conventional cloud workflow scheduling techniques.Although some scheduling methods for Sls have been proposed,most of them are no more applicable to the latest Sls,as they have evolved by eliminating bidding and simplifying the pricing model.This study focuses on how to minimize the execution cost with a deadline constraint when deploying a workflow on volatile Sls in cloud environments.Based on Monte Carlo simulation and list scheduling,a stochastic scheduling method called MCLS is devised to optimize a utility function introduced for this problem.With the Monte Carlo simulation framework,MCLS employs sampled task execution time to build solutions via deadline distribution and list scheduling,and then returns the most robust solution from all the candidates with a specific evaluation mechanism and selection criteria.Experimental results show that the performance of MCLS is more competitive comparedwithtraditionalalgorithms.

关键词： constrained optimization Monte Carlo simulation robustness Spot Instances(Sls) workflow scheduling

Corporate Credit Ratings Based on Hierarchical Heterogeneous Graph Neural Networks

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Machine Intelligence Research 2024年第2期21卷 257-271页

作者： Bo-Jing Feng Xi Cheng Hao-Nan Xu wen-fang Xue Center for Research on Intelligent Perception and Computing National Laboratory of Pattern RecognitionInstitute of AutomationChinese Academy of SciencesBeijing 100190China

order to help investors understand the credit status of target corporations and reduce investment risks,the corporate credit rating model has become an important evaluation tool in the financial market.These models are based on statistical learning,machine learning and deep learning especially graph neural networks(GNNs).However,we found that only few models take the hierarchy,heterogeneity or unlabeled data into account in the actual corporate credit rating process.Therefore,we propose a novel framework named hierarchical heterogeneous graph neural networks(HHGNN),which can fully model the hierarchy of corporate features and the heterogeneity of relationships between corporations.In addition,we design an adversarial learning block to make full use of the rich unlabeled samples in the financial data.Extensive experiments conducted on the public-listed corporate rating dataset prove that HHGNN achieves SOTA compared to the baseline methods.

关键词： Corporate credit rating hierarchical relation heterogeneous graph neural networks adversarial learning

Charge regulation by ferromagnetic metal/LiF spin-polarized interface for high-performance Li metal anodes

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Rare Metals 2024年第3期43卷 995-1005页

作者： Ming-Yang Feng Shuang Zhou Yi-fang Zhang Ya-Ping Wang Chun-Yan Fu Jian-wen Li Yuan-Lang Wan zhi-Jia Zhang Yong Jiang An-Qiang Pan State Key Laboratory of Powder Metallurgy School of Materials Science and EngineeringCentral South UniversityChangsha410083China State Key Laboratory of Separation Membranes and Membrane Processes Tianjin Key Laboratory of Advanced Fibers and Energy StorageSchool of Material Science and EngineeringTiangong UniversityTianjin300387China School of Materials Science and Engineering Hebei University of TechnologyTianjin300130China

The interfacial characteristics of the Li metal anode(LMA)play a crucial role in its overall performance.Despite various materials being applied to modify the interface,a comprehensive understanding of their specific mechanisms remains to be investigated.Herein,we have prepared carbon cloth(CC)frameworks with their surfaces modified using ferromagnetic metal/LiF heterogeneous films(T^(M)-LiF-CC)as the substrate for LMA,which exhibit superior electrochemical performance.Utilizing ferromagnetic Co as a representative example,our study demonstrates that the enhanced performance of Co-LiF-CC,compared to bare CC,is attributed to the spinpolarized interface contributed by the Co/LiF heterostructure.Co and LiF play individual roles in redistributing electrons and Li^(+)to promote homogeneous Li deposition.Co nanoparticles play a crucial role in generating strong surface capacitance by storing electrons in spin-split bands,while LiF,with low surface diffusion barriers,ensures fast transportation of Li^(+).The Co-LiF-CC@Li electrodes deliver long lives of 7400 and 3600 h at 1 and 2 mA·cm^(-2)in symmetric cells,respectively;moreover,they enable full batteries with high and durable capacities,particularly when the N/P ratios are low(3.3 or even 1.7).

关键词： Lithium metal anode Interfacial charge Ferromagnetic metal Lithium fluoride Spin polarization

Monomorphic epitheliotropic intestinal T-cell lymphoma with bone marrow involved: A case report

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World Journal of Clinical Cases 2024年第4期12卷 814-819页

作者： Fen-Juan Zhang wen-Juan fang Cang-Jian Zhang Department of Hematology Lishui Municipal Central HospitalLishui 323000Zhejiang ProvinceChina

BACKGROUND Monomorphic epithelial intestinal T-cell lymphoma(MEITL)is a rare type of peripheral T-cell lymphoma.The clinical manifestations are diarrhea,abdominal pain,perforation and an abdominal mass.CASE SUMMARY We present a 52-year-old female patient who was diagnosed with MEITL.Further disease progression was observed after multiline chemotherapy.Eventually,the patient died of a severe infection.CONCLUSION MEITL is a rare intestinal primary T-cell lymphoma with aggressive behavior,a high risk of severe life-threatening complications,and a poor prognosis.

关键词： Monomorphic epithelial intestinal T-cell lymphoma Autologous stem cell transplantation Chemotherapeutics Case report

Conceptual design of a 714-MHz RFQ for compact proton injectors and development of a new tuning algorithm on its aluminium prototype

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Nuclear Science and Techniques 2024年第1期35卷 45-58页

作者： Yi-Xing Lu wen-Cheng fang Yu-Sen Guo Zhen-Tang Zhao Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800China University of Chinese Academy of Sciences Beijing 101408China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201204China Shanghai Key Laboratory of Cryogenics&Superconducting RF Technology Shanghai 201800China ShanghaiTech University Shanghai 201210China

Radio frequency quadrupoles(RFQs),which are crucial components of proton injectors,significantly affect the performance of proton accelerator facilities.An RFQ with a high frequency of 714 MHz dedicated to compact proton injectors for medi-cal applications is designed in this study.The RFQ is designed to accelerate proton beams from 50 keV to 4 MeV within a short length of 2 m and can be matched closely with the downstream drift tube linac to capture more particles through a preliminary optimization.To develop an advanced RFQ,challenging techniques,including fabrication and tuning method,must be evaluated and verified using a prototype.An aluminium prototype is derived from the conceptual design of the RFQ and then redesigned to confirm the radio frequency performance,fabrication procedure,and feasibility of the tuning algorithm.Eventually,a new tuning algorithm based on the response matrix and least-squares method is developed,which yields favorable results based on the prototype,i.e.,the errors of the dipole and quadrupole components reduced to a low level after several tuning iterations.Benefiting from the conceptual design and techniques obtained from the prototype,the formal mechanical design of the 2-m RFQ is ready for the next manufacturing step.

关键词： Compact proton injector RFQ IH-DTL High gradient Tuning

Evaluation of dry eye disease symptomatology and mental health status among patients with different COVID-19 statuses

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 822-830页

作者： fang Ruan wen-Jun Kong Qian Fan Hong-Wei Dong Wei Zhang wen-Bin Wei Ying Jie Department of Ophthalmology Beijing You’an HospitalCapital Medical UniversityBeijing Infectious Eye Disease Diagnosis and Treatment CenterBeijing 100069China Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing Institute of OphthalmologyBeijing Ophthalmology and Visual Sciences Key LabBeijing 100730China Tianjin Eye Hospital Tianjin Key Lab of Ophthalmology and Visual ScienceTianjin Eye InstituteNankai University Affiliated Eye HospitalNankai University Eye InstituteNankai UniversityClinical College of OphthalmologyTianjin Medical UniversityTianjin 300020China

AIM:To evaluate dry eye disease(DED)symptomatology and mental health status in different COVID-19 patients.METHODS:A cross-sectional observational design was used.Totally 123 eligible adults(46.34%of men,age range,18-59y)with COVID-19 included in the study from August to November,2022.Ocular Surface Disease Index(OSDI),Five-item Dry Eye Questionnaire(DEQ-5),Hospital Anxiety and Depression Scale(HADS),and Pittsburgh Sleep Quality Index(PSQI)were used in this study.RESULTS:OSDI scores were 6.82(1.25,15.91)in asymptomatic carriers,7.35(2.50,18.38)in mild cases,and 16.67(4.43,28.04)in recurrent cases,with 30.00%,35.56%,and 57.89%,respectively evaluated as having DED symptoms(χ2=7.049,P=0.029).DEQ-5 score varied from 2.00(0,6.00)in asymptomatic carriers,3.00(0,8.00)in mild cases,and 8.00(5.00,10.00)in recurrent cases,with 27.50%,33.33%,and 55.26%,respectively assessed as having DED symptoms(χ2=8.532,P=0.014).The prevalence of clinical anxiety(50.00%)and depression(47.37%)symptoms were also significantly higher in patients with recurrent infection(χ2=24.541,P<0.001;χ2=30.871,P<0.001).Recurrent infection was a risk factor for high OSDI scores[odds ratio,2.562;95%confidence interval(CI),1.631-7.979;P=0.033]and DEQ-5 scores(odds ratio,3.353;95%CI,1.038-8.834;P=0.043),whereas having a fixed occupation was a protective factor for OSDI scores(odds ratio,0.088;95%CI,0.022-0.360;P=0.001)and DEQ-5 scores(odds ratio,0.126;95%CI,0.039-0.405;P=0.001).CONCLUSION:Patients with recurrent COVID-19 have more severe symptoms of DED,anxiety,and depression.

关键词： COVID-19 dry eye disease recurrent infection mental health

Advance in reversible Zn anodes promoted by 2D materials

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Rare Metals 2024年第4期43卷 1350-1369页

作者： Shu-Yuan Lei Jin-Xiu Feng Yu-Chao Chen Dong Zheng wen-Xian Liu wen-Hui Shi fang-fang Wu Xie-Hong Cao School of Materials Science and Engineering Zhejiang University of Technology Center for Membrane Separation and Water Science and Technology College of Chemical EngineeringZhejiang University of Technology

With the growing energy demand associated with high safety and low-cost requirement,aqueous zinc-ion batteries(AZIBs) have been considered as one of the most promising next-generation batteries.However,some key issues,such as uncontrollable dendrites growth,severe corrosion,hydrogen evolution and side reactions of Zn anodes during charge/discharge process,have hindered its pragmatic applications.Two-dimensional(2D) materials hold advantages of unique physical and chemical properties,large surface areas and abundant active sites,which have been successfully used to overcome the above shortcomings of Zn anodes in recent years.In this review,the issues and challenges of Zn anodes are outlined.Then,the state-of-the-art progress on Zn anodes modification based on 2D materials such as graphene,2D metal carbides and nitrides(MXenes),2D metal-organic frameworks(MOFs),2D covalent organic frameworks(COFs),2D transition metal compounds and other 2D materials is discussed in detail.Finally,the perspectives of employing 2D materials in highly reversible Zn anodes are summarized and discussed.

关键词： 2D materials Aqueous zinc-ion battery Zn anodes Dendrites growth

A Low Cost, Green Sustainable and Biodegradable Biomass-based Fluorine-free Water and Oil Repellent

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Chinese Journal of Polymer Science 2024年第4期42卷 480-491页

作者： zhi-Wei Shen Shu-Feng Hu Chen Zeng Wei-Qing Kong Mei-fang Zhu State Key Laboratory for Modification of Chemical Fibers&Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China State Key Laboratory of Pulp and Paper Engineering School of Light Industry and EngineeringSouth China University of TechnologyGuangzhou510630China

With the global ban on plastics intensifying, the substitution of plastic with paper has garnered increasing attention. However, the inadequate water and oil repellency of pulp molding hinders its practical applications. Currently, the common method to enhance the oil and water repellency of pulp molding is by adding fluorinated water and oil repellents. Nevertheless, fluorinated compounds are environmentally and physiologically harmful. Therefore, the development of fluorine-free, water and oil repellent alternatives is crucial. In this study, chitosan and stearic acid were utilized as the first and second layers of the oil and water repellent coatings, respectively. The coated samples exhibited favorable water repellency, with a water contact angle of 116.4°, and excellent oil repellency, achieving a 12/12 rating on the kit scale. Importantly, the samples did not exhibit any leakage after being soaked in hot water and hot oil at 95±5℃ for 30 min, demonstrating remarkable performance as a barrier against hot water and oil. Moreover, the coated samples displayed outstanding mechanical properties, thermal stability, biodegradability, and recyclability. The approach presented in this study is simple, cost-effective, environmentally friendly, and represents a promising technique for producing fluoride-free, oil-and water-resistant pulp molding products.

关键词： Biomass Fluoride-free Oil-andwater-resistant Plasticfree