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TAILORED FINITE CELL METHOD FOR SOLVING HELMHOLTZ EQUATION IN LAYERED HETEROGENEOUS MEDIUM

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Journal of Computational Mathematics 2012年第4期30卷 381-391页

作者： zhong-yi huang Xu Yang Department of Mathematical Sciences Tsinghua University Beijing 100084 China Department of Mathematics Courant Institute of Mathematical Sciences New York UniversityNew York NY 10012 USA

In this paper, we propose a tailored finite cell method for the computation of two- dimensional Helmholtz equation in layered heterogeneous medium. The idea underlying the method is to construct a numerical scheme based on a local approximation of the solution to Helmholtz equation. This provides a computational tool of achieving high accuracy with coarse mesh even for large wave number （high frequency）. The stability analysis and error estimates of this method are also proved. We present several numerical results to show its efficiency and accuracy.

关键词： Tailored finite cell method Helmholtz equation Heterogeneous media Som-merfeld condition.

High-Efficiency Dynamic Scanning Strategy for Powder Bed Fusion by Controlling Temperature Field of the Heat-Affected Zone

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 203-214页

作者： Xiaokang huang Xiaoyong Tian Qi zhong Shunwen He Cunbao Huo yi Cao Zhiqiang Tong Dichen Li State Key Laboratory of Manufacturing Systems Engineering Xi’an Jiaotong UniversityXian 710049China

Improvement of fabrication efficiency and part performance was the main challenge for the large-scale powder bed fusion(PBF)*** this study,a dynamic monitoring and feedback system of powder bed temperature field using an infrared thermal imager has been established and integrated into a four-laser PBF equipment with a working area of 2000 mm×2000 *** heat-affected zone(HAZ)temperature field has been controlled by adjusting the scanning speed ***,the relationship among spot size,HAZ temperature,and part performance has been *** fluctuation of the HAZ temperature in four-laser scanning areas was decreased from 30.85℃to 17.41℃.Thus,the consistency of the sintering performance of the produced large component has been *** on the controllable temperature field,a dynamically adjusting strategy for laser spot size was proposed,by which the fabrication efficiency was improved up to 65.38%.The current research results were of great significance to the further industrial applications of large-scale PBF equipment.

关键词： Powder bed fusion Efficiency Large-scale Spot size Heat-affected zone(HAZ)

Effect of lens surgery on health-related quality of life in preschool children with congenital ectopia lentis

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 66-72页

作者： Yan-Qiao huang Qian-zhong Cao yi-Yao Wang yi-Jing Zhou Dan-ying Zheng State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangdong Provincial Key Laboratory of Ophthalmology and Visual ScienceGuangdong Provincial Clinical Research Center for Ocular DiseasesGuangzhou 510060Guangdong ProvinceChina

AIM:To evaluate the effect of lens surgery on health-related quality of life(HRQoL)of preschool children with congenital ectopia lentis(CEL).METHODS:A prospective self-controlled study was conducted in zhongshan Ophthalmic *** aged from 5 to 7y whom were diagnosed with CEL and underwent phacoemulsification with scleral-fixated posterior chamber intraocular lens implantation and their parents were enrolled in this *** of them completed the child and proxy(parental)PedsQL™4.0 before and after the *** preoperative scores were compared to their postoperative *** analyses were performed based on gender and preoperative bilateral presenting visual acuity of the ***:Thirty-two children with CEL successfully underwent surgery without any complications,among whom 8 had monocular surgery and 24 had binocular *** and postoperative questionnaires were completed by 32 child-parent *** intervention could significantly improve the vision of affected children(P<0.001).The medians of physical,psychosocial and total health scores self-reported by the children were 68.75(62.50,81.25),65.00(60.00,80.00)and 67.39(60.87,78.26)preoperatively and were 93.75(87.50,100.00),90.00(83.33,96.67)and 89.13(85.32,95.65)*** preoperative scores of the affected children were significantly lower in all scales than age-matched healthy children(P<0.001).All the postoperative scores were significantly higher than the preoperative scores in affected children and their parents(P<0.001).In the physical functioning evaluation,the preoperative score reported by parents of girls was higher than parents of boys(P=0.041),and the postoperative score of girls was higher than that of boys(P=0.036).CONCLUSION:CEL is associated with significantly worse quality of life in preschool *** intervention can significantly improve the HRQoL in affected children from both personal and family perspective.

关键词： congenital ectopia lentis surgical intervention health-related quality of life preschool children

Synthesis of Poly(p-phenyleneethynylene)s with Crosslinkable End or Side Groups and Its Solid State Structure and Optical Properties Before and after Crosslinking

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Chemical Research in Chinese Universities 2009年第5期25卷 767-772页

作者： WANG Wen-zhong LIU zhong-yi huang Peng-cheng Department of Polymer Materials and Composites School of Materials Science and Engineering Beihang University Beijing 100083 P. R. China

Two crosslinkable poly（p-phenyleneethynylene）s（PPEs）： poly[2,5-di（2＇-ethyl-hexyloxy）-1,4-phenylenecthynylene] with end-capped vinyl（PPE1） and poly[2,5-di（allyloxy）-1,4-phenyleneethynylene-2,5-di（2＇-ethyl-hexyloxy）-1,4-phenyleneethynylene]（PPE2） were synthesized. Via the thermal addition reactions of vinyl end groups of PPE1 and allyloxy side groups of PPE2, crosslinked polymers C-PPE1 and C-PPE2 were obtained, respectively. The two polymers were characterized by wide-angle X-ray diffraction（WXRD）, ultraviolet-visible（UV-Vis） absorption, and photoluminescence（PL）. The results indicate that in the solid state, the polymer chains of PPE1 were packed with a low degree of crystallinity because of the sterically hindered（2＇-ethyl-hexyl）oxy branched side chains, but, because of the introduction of allyloxy side chains, the polymer chains of PPE2 were packed in an order fashion with a high degree of crystallinity. Because of the high crosslinking density in C-PPE2, the formation of aggregates and excimer was hampered by the formed crosslinking network more effectively in C-PPE2 film than in C-PPE1 film.

关键词： Poly(p-phenyleneethynylene) Crosslinkable polymer Optical property Packing fashion

Optimal Cooperative Secondary Control for Islanded DC Microgrids via a Fully Actuated Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 405-417页

作者： yi Yu Guo-Ping Liu yi huang Peng Shi IEEE Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and TechnologyShenzhen 518055China School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China School of Electrical and Mechanical Engineering the University of AdelaideSA 5005Australia Research and Innovation Centre Obuda University1034 BudapestHungary

DC-DC converter-based multi-bus DC microgrids(MGs) in series have received much attention, where the conflict between voltage recovery and current balancing has been a hot topic. The lack of models that accurately portray the electrical characteristics of actual MGs while is controller design-friendly has kept the issue active. To this end, this paper establishes a large-signal model containing the comprehensive dynamical behavior of the DC MGs based on the theory of high-order fully actuated systems, and proposes distributed optimal control based on this. The proposed secondary control method can achieve the two goals of voltage recovery and current sharing for multi-bus DC MGs. Additionally, the simple structure of the proposed approach is similar to one based on droop control, which allows this control technique to be easily implemented in a variety of modern microgrids with different configurations. In contrast to existing studies, the process of controller design in this paper is closely tied to the actual dynamics of the MGs. It is a prominent feature that enables engineers to customize the performance metrics of the system. In addition, the analysis of the stability of the closed-loop DC microgrid system, as well as the optimality and consensus of current sharing are given. Finally, a scaled-down solar and battery-based microgrid prototype with maximum power point tracking controller is developed in the laboratory to experimentally test the efficacy of the proposed control method.

关键词： DC microgrids distributed control high-order fully actuated system approach linear quadratic regulator microgrid modeling secondary control

A simple photochemical method for surface fluorination using perfluoroketones

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Chinese Chemical Letters 2024年第5期35卷 254-258页

作者： Zhiwei zhong Yanbin huang Wantai Yang Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

Surface fluorination of conventional polymers can give them desirable surface properties similar to the expensive and difficult-to-process ***,traditional surface fluorination techniques often require toxic reagents and special ***,we report a simple and effective polymer surface fluorination method by using safe and inexpensive perfluoro-2-methyl-3-pentanone(PFMP,C_(2)F_(5)C(=O)CF(CF_(3))_(2))and UV *** method is applicable to various polymer materials,and generates nanometer-thick fluorinated layer on the outermost surface,significantly changing their surface properties without changing the surface morphology.

关键词： Surface fluorination Perfluoroketone UV irradiation Photochemistry Surface free energy

Reliable calculations of nuclear binding energies by the Gaussian process of machine learning

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Nuclear Science and Techniques 2024年第6期35卷 130-144页

作者： Zi-yi Yuan Dong Bai Zhen Wang zhong-Zhou Ren School of Physics Science and Engineering Tongji UniversityShanghai 200092China College of Science Hohai UniversityNanjing 211100China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China

Reliable calculations of nuclear binding energies are crucial for advancing the research of nuclear physics. Machine learning provides an innovative approach to exploring complex physical problems. In this study, the nuclear binding energies are modeled directly using a machine-learning method called the Gaussian process. First, the binding energies for 2238 nuclei with Z > 20 and N > 20 are calculated using the Gaussian process in a physically motivated feature space, yielding an average deviation of 0.046 MeV and a standard deviation of 0.066 MeV. The results show the good learning ability of the Gaussian process in the studies of binding energies. Then, the predictive power of the Gaussian process is studied by calculating the binding energies for 108 nuclei newly included in AME2020. The theoretical results are in good agreement with the experimental data, reflecting the good predictive power of the Gaussian process. Moreover, the α-decay energies for 1169 nuclei with 50 ≤ Z ≤ 110 are derived from the theoretical binding energies calculated using the Gaussian process. The average deviation and the standard deviation are, respectively, 0.047 MeV and 0.070 MeV. Noticeably, the calculated α-decay energies for the two new isotopes ^ (204 )Ac(huang et al. Phys Lett B 834, 137484(2022)) and ^ (207) Th(Yang et al. Phys Rev C 105, L051302(2022)) agree well with the latest experimental data. These results demonstrate that the Gaussian process is reliable for the calculations of nuclear binding energies. Finally, the α-decay properties of some unknown actinide nuclei are predicted using the Gaussian process. The predicted results can be useful guides for future research on binding energies and α-decay properties.

关键词： Nuclear binding energies decay Machine learning Gaussian process

The association and underlying mechanism of the digit ratio(2D:4D)in hypospadias

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Asian Journal of Andrology 2024年第4期26卷 356-365页

作者： Yu Ding Zu-Quan Chen Wen-Feng Pan Hao-Jie Chen Min Wu yi-Qing Lyu Hua Xie yi-Chen huang zhong-zhong Chen Fang Chen Department of Urology Shanghai Children’s HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200062China Urogenital Development Research Center Shanghai Children’s HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200062China Clinical Research Center for Hypospadias Pediatric CollegeShanghai Jiao Tong University School of MedicineShanghai 200062China.

The second-to-fourth digit(2D:4D)ratio is thought to be associated with prenatal androgen ***,the relationship between the 2D:4D ratio and hypospadias is poorly understood,and its molecular mechanism is not *** this study,by analyzing the hand digit length of 142 boys with hypospadias(23 distal,68 middle,and 51 proximal)and 196 controls enrolled in Shanghai Children’s Hospital(Shanghai,China)from December 2020 to December 2021,we found that the 2D:4D ratio was significantly increased in boys with hypospadias(P<0.001)and it was positively correlated with the severity of the *** was further verified by the comparison of control mice and prenatal low testosterone mice model obtained by knocking out the risk gene(dynein axonemal heavy chain 8[DNAH8])associated with ***,the discrepancy was mainly caused by a shift in *** characterization of a mouse model validated that low testosterone levels during pregnancy can impair the growth and development of *** mechanistic explorations revealed that during the androgen-sensitive window,the downregulation of the androgen receptor(AR)caused by low testosterone levels,as well as the suppressed expression of chondrocyte proliferation-related genes such as Wnt family member 5a(Wnt5a),Wnt5b,Smad family member 2(Smad2),and Smad3;mitochondrial function-related genes in cartilage such as AMP-activated protein kinase(AMPK)and nuclear respiratory factor 1(Nrf-1);and vascular development-related genes such as myosin light chain(MLC),notch receptor 3(Notch3),and sphingosine kinase 1(Sphk1),are responsible for the limitation of 4D growth,which results in a higher 2D:4D ratio in boys with hypospadias via decreased endochondral *** study indicates that the ratio of 2D:4D is a risk marker of hypospadias and provides a potential molecular mechanism.

关键词： androgen receptor digit ratio(2D:4D) endochondral ossification hypospadias testosterone level

Ginsenoside modified lipid-coated perfluorocarbon nanodroplets: A novel approach to reduce complement protein adsorption and prolong in vivo circulation

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1845-1863页

作者： Jie Zhou Binyang Gao Huan Zhang Rui Yang Jianbo huang Xin Li yi zhong Yan Wang Xiaoxia Zhu Yan Luo Feng Yan Ultrasound Department of West China Hospital Sichuan UniversityChengdu 610041China Laboratory of Ultrasound Imaging of West China Hospital Sichuan UniversityChengdu 610041China West China Washington Mitochondria and Metabolism Research Center West China HospitalSichuan UniversityChengdu 610041China Research Core Facilities of West China Hospital Sichuan UniversityChengdu 610041China

Lipid-coated perfluorocarbon nanodroplets(lp-NDs)hold great promise in bio-medicine as vehicles for drug delivery,molecular imaging and vaccine ***,their clinical utility is restricted by limited targeted accumulation,attributed to the innate immune system(IIS),which acts as the initial defense mechanism in *** study aimed to optimize lp-ND formulations to mini-mize non-specific clearance by the ***(Gs),the principal components of Panax ginseng,possessing complement inhibition ability,structural similarity to cholesterol,and comparable fat solubi-lity to phospholipids,were used as promising candidate IIS *** different types of ginsenoside-based Ip-NDs(Gs Ip-NDs)were created,and their efficacy in reducing IS recognition was *** Gs p-NDs were observed to inhibit the adsorption of C3 in the protein corona(PC)and the generation of *** Gs to Ip-NDs reduced complement adsorption and phagocytosis,resulting in a longer blood circulation time in vivo compared to lp-NDs that did not contain *** results suggest that Gs can act as anti-complement and anti-phagocytosis adjuvants,potentially reducing non-specific clear-ance by the IS and improving lifespan.

关键词： Lipid-coated perfluorocarbon nanodroplets Protein corona Complement C3 Phagocytosis Ginsenosidelipid-coated perfluorocarbon nanodroplets Innate immune system Complement system Mononuclear phagocytic system