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Concentration breaking on two optimization problems

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Science China Mathematics 2024年第7期67卷 1555-1570页

作者： Yong huang Qinfeng li Qiuqi li School of Mathematics Hunan UniversityChangsha410082China

In the present paper, we study the boundary concentration-breaking phenomena on two thermal insulation problems considered on lipschitz domains, based on Serrin's overdetermined result, the perturbation argument, and a comparison of Laplacian eigenvalues with different boundary conditions. Since neither of the functionals in the two problems is C^(1), another key ingredient is to obtain the global H?lder regularity of minimizers of both problems on lipschitz domains. Also, the exact dependence on the domain of breaking thresholds is given in the first problem, and the breaking values are obtained in the second problem on ball domains, which are related to 2π in dimension 2.

关键词： spectral inequalities symmetry breaking Laplacian eigenvalue

Increased N6-methyladenosine is related to the promotion of the methyltransferase METTL14 in ovarian aging

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Genes & Diseases 2024年第3期11卷 151-154页

作者： Chunfeng Qian Zhenxing liu Yonghong Qian Jie Ding Rulei Chen Han su Minghong Shen Hong li Boxian huang State Key Laboratory of Reproductive Medicine and Offspring Health Suzhou Affliated Hospital of Nanjing Medicine and Offspring HealthSuzhou Affiliated Hospital of Nanjing Medical UniversitySuzhouMunicipal HospitalGusu SchoolNanjing Medical UniversitySuzhouJiangsu 215002China Department of Gynecology Affliated Suzhou Hospital of Nanjing Medical UniversitySuzhou Municipal HospitalGusu School of Nanjing Medical UniversitySuzhouJiangsu 215002China Department of Pathology Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhou Municipal HospitalGusu School of Nanjing Medical UniversitySuzhouJiangsu 215002China

The ovary is a vital female reproductive organ that functions to produce oocyte gametes and cyclically expressed sex hormones to maintain reproductive capacity and hormone *** aging,characterized by declines in follicle quantity and oocyte quality,leads to premature ovarian failure,premature ovarian insufficiency,or diminished ovarian reserve,thus contributing to female *** gene-expression signatures from RNA transcriptional level and post-transcriptional regulation are relative to oocyte quality and reproductive age.

关键词： promotion signature maintain

Transcutaneous electrical acupoint stimulation benefits postoperative pain relief of oocyte retrieval:A randomized controlled trial

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Journal of Integrative Medicine 2024年第1期22卷 32-38页

作者： li-ying liu Yang su Rong-rong Wang Yuan-yuan Lai Lei huang Yi-ting li Xin-yue Tao Meng-hua su Xiao-yan Zheng Shi-chen huang Yong-na Wu Si-yi Yu Fan-rong liang Jie Yang Acupuncture and Tuina School Chengdu University of Traditional Chinese MedicineChengdu 610000Sichuan ProvinceChina Traditional Chinese Medicine Department Sichuan Jinxin Xi’nan Women's and Children's HospitalChengdu 610000Sichuan ProvinceChina

Background Transvaginal oocyte retrieval is frequently followed by adverse events related to anesthesia and the *** research showed that transcutaneous electrical acupoint stimulation(TEAS)can relieve intraoperative pain and postoperative *** This study examined whether TEAS can alleviate pain and relieve adverse symptoms after oocyte ***,setting,participants and interventions Altogether 128 patients were randomly divided into the TEAS group and the mock TEAS *** two groups received a 30-minute-long TEAS or mock TEAS treatment that began 30 min after oocyte *** outcome measures The primary outcome was the visual analog scale(VAS)pain *** outcomes were pressure pain threshold,McGill score,pain rating index(PRI),present pain intensity(PPI),VAS stress score,VAS anxiety score,and postoperative adverse *** The baseline characteristics of the two groups were comparable(P>0.05).The VAS pain scores of the TEAS group were lower than those of the mock TEAS group at 60 and 90 min after oocyte retrieval(Psuch as nervousness and anxiety(P>0.05).The TEAS group was superior to the mock TEAS group for relieving postoperative adverse symptoms(Plieve postoperative pain and postoperative adverse symptoms for patients undergoing oocyte retrieval.

关键词： Transcutaneous electrical acupoint stimulation Fertilization Embryo transfer Oocyte retrieval Pain Randomized controlled trial

Cooperative Anti-Jamming and Interference Mitigation for UAV Networks: A Local Altruistic Game Approach

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China Communications 2024年第2期21卷 183-196页

作者： Yueyue su Nan Qi Zanqi huang Rugui Yao Luliang Jia College of Electronic Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China School of Space Information Space Engineering UniversityBeijing 101416China

To improve the anti-jamming and interference mitigation ability of the UAV-aided communication systems, this paper investigates the channel selection optimization problem in face of both internal mutual interference and external malicious jamming. A cooperative anti-jamming and interference mitigation method based on local altruistic is proposed to optimize UAVs’ channel selection. Specifically, a Stackelberg game is modeled to formulate the confrontation relationship between UAVs and the jammer. A local altruistic game is modeled with each UAV considering the utilities of both itself and other UAVs. A distributed cooperative anti-jamming and interference mitigation algorithm is proposed to obtain the Stackelberg equilibrium. Finally, the convergence of the proposed algorithm and the impact of the transmission power on the system loss value are analyzed, and the anti-jamming performance of the proposed algorithm can be improved by around 64% compared with the existing algorithms.

关键词： channel selection cooperative antijamming and interference mitigation local altruistic game Stackelberg game unmanned aerial vehicle(UAV)

Prediction models of burst strength degradation for casing with considerations of both wear and corrosion

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Petroleum Science 2024年第1期21卷 458-474页

作者： Jie-li Wang Wen-Jun huang De-li Gao MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China

Casing wear and casing corrosion are serious problems affecting casing integrity failure in deep and ultra-deep *** paper aims to predict the casing burst strength with considerations of both wear and ***,the crescent wear shape is simplified into three categories according to common mathematical ***,based on the mechano-electrochemical(M-E)interaction,the prediction model of corrosion depth is built with worn depth as the initial condition,and the prediction models of burst strength of the worn casing and corroded casing are ***,the accuracy of different prediction models is validated by numerical simulation,and the main influence factors on casing strength are *** last,the theoretical models are applied to an ultra-deep well in Northwest China,and the dangerous well sections caused by wear and corrosion are predicted,and the corrosion rate threshold to ensure the safety of casing is *** results show that the existence of wear defects results in a stress concentration and enhanced M-E interaction on corrosion depth *** accuracy of different mathematical models is different:the slot ring model is most accurate for predicting corrosion depth,and the eccentric model is most accurate for predicting the burst strength of corroded *** burst strength of the casing will be overestimated by more than one-third if the M-E interaction is neglected,so the coupling effect of wear and corrosion should be sufficiently considered in casing integrity evaluation.

关键词： Deep well Casing integrity Casing wear Casing corrosion Burst strength

Microstructure and Internal Friction Behavior of Laser 3D Printed Fe-Based Amorphous Composites

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 196-204页

作者： Shuilong huang Qingjun Chen li Ji Kan Wang Guosheng huang School of Material Science and Engineering Nanchang Hangkong UniversityNanchang330063China State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research Institute(LSMRI)Qingdao266237China

Laser 3D printing,also known as laser additive manufacturing(LAM),is favored for its ability to form bulk metallic glass(BMG)and its composite materials(BMGcs)with freeform *** this work,two different kinds of Fe_(41)Co_(7)Cr_(15)Mo_(14)C_(15)B_(6)Y_(2)amorphous coatings(A and B)were prepared by using LAM technology under air-and water-cooled conditions,respectively;meanwhile,to reduce the cracks generated due to the residual thermal stresses,coating C obtained by air-sweep annealing of B with a low energy-density *** morphology and amorphous content and microstructure of the coatings were investigated,the results show many cracks in coating B deposited under water-cooled conditions,and its microstructure shows an amorphous-crystal-nanocrystalline mixed *** was suppressed in coating C,obtained by air-sweep annealing based on coating B,but the amorphous content was reduced from 32.6 to 13.4%.And the hardness and corrosion resistance of the coating will increase with the increase in the amorphous ***,the internal friction behavior of a BMGcs was prepared on the basis of the process of sample C is compared with that of as-cast amorphous *** results show that the low temperature internal friction behavior of BMGcs is affected by the defects produced during printing,and the high temperature internal friction behavior is affected by the precipitated hard phase.

关键词： Laser 3D printing Amorphous coating Microstructure Corrosion resistance Internal friction behavior

Cu nanowire array with designed interphases enabling high performance Si anode toward flexible lithium-ion battery

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Nano Research 2024年第3期17卷 1516-1524页

作者： Pengfei su Ziqi Zhang linshan Luo Zhiyong Zhang Chaofei Lan Yahui li Shaowen Xu Shanpeng Pei Guangyang lin Cheng li Xiang Han Wei huang Songyan Chen Fujian Provincial Key Laboratory of Semiconductors and Applications Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient DevicesDepartment of PhysicsXiamen UniversityXiamen 361005China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037China Science and Technology on Analog Integrated Circuit Laboratory Chongqing 400060China Shandong Electric Power Engineering Consulting Institute Co. Ltd.Jinan 250013China

To meet the growing demand for wearable smart electronic devices,the development of flexible lithium-ion batteries(liBs)is *** is an ideal candidate for the anode material of flexible lithium-ion batteries due to its high specific capacity,low working potential,and earth *** largest challenge in developing a flexible silicon anode is how to maintain structural integrity and ensure stable electrochemical reactions during external *** this work,we propose a novel design for fabricating core–shell electrodes based on a copper nanowire(CuNW)array core and magnetron sputtered Si/C *** nanowire array structure has characteristics of bending under longitudinal stress and twisting under transverse stress,which helps to maintain the mechanical stability of the structure during electrode bending and *** low-temperature annealing generates a small amount of Cu3Si alloy,which enhances the connection strength between Si and the conductive network and solves the poor conductivity problem of Si,which is known as a semiconductor *** unique configuration design of CuNW@Si@C-400℃ leads to stable long cycle performance of 1109 mAh∙g^(-1) after 1000 cycles and excellent rate performance of 500 mAh∙g^(-1) at a current density of 10 A∙g^(-1).Furthermore,the CuNW@Si@C-400℃||liFePO_(4)(LFP)full battery demonstrates excellent flexibility,with a capacity retention of more than 96%after 100 *** study provides a promising strategy for the development of flexible lithium-ion batteries.

关键词： flexible lithium-ion battery silicon anode magnetron sputtering core–shell electrode Cu nanowire array

Preparation of CIP@TiO_(2) composite with broadband electromagnetic wave absorption properties

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 197-205页

作者： Qiang su Hanqun Wang Yunfei He Dongdong liu Xiaoxiao huang Bo Zhong School of Materials Science and Engineering Harbin Institute of TechnologyWeihaiWeihai 264209China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Scholars aim for the improved impedance matching (Z) of materials while maintaining their excellent wave absorption properties. Based on the hydrolysis characteristics of isopropyl titanate, a simple preparation process for the coating of carbonyl iron powder(CIP) with TiO_(2) was designed. Given the TiO2coating, the Z of the CIP@TiO_(2) composite was adjusted well by decreasing the dielectric constant. Moreover, the interfacial polarization of CIP@TiO_(2) was enhanced. Ultimately, the electromagnetic-wave (EMW) absorption property of the CIP@TiO_(2)composite was improved substantially, the minimum reflection loss reached-46.07 dB, and the effective absorption bandwidth can reach 8 GHz at the composite thickness of 1.5 mm. Moreover, compared with CIP, the oxidation resistance of CIP@TiO_(2)showed remarkable improvement. The results revealed that the oxidation starting temperature of CIP@TiO_(2) as about 400℃,whereas the uncoated CIP had an oxidation starting temperature of approximately 250℃. Moreover, the largest oxidation rate temperature of CIP@TiO_(2) increased to around 550℃. This work opens up a novel strategy for the production of high-performance EMW absorbers via structural design.

关键词： carbonyl iron@titanium dioxide electromagnetic-wave absorption impedance matching oxidation resistance

Quantum speedup and limitations on matroid property problems

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Frontiers of Computer Science 2024年第4期18卷 189-196页

作者： Xiaowei huang Jingquan LUO Lvzhou li Institute of Quantum Computing and Computer Theory School of Computer Science and EngineeringSun Yat-sen UniversityGuangzhou 510006China

Matroid theory has been developed to be a mature branch of mathematics and has extensive applications in combinatorial optimization,algorithm design and so *** the other hand,quantum computing has attracted much attention and has been shown to surpass classical computing on solving some computational ***,crossover studies of the two fields seem to be missing in the *** paper initiates the study of quantum algorithms for matroid property *** is shown that quadratic quantum speedup is possible for the calculation problem of finding the girth or the number of circuits(bases,flats,hyperplanes)of a matroid,and for the decision problem of deciding whether a matroid is uniform or Eulerian,by giving a uniform lower boundΩ■on the query complexity of all these *** the other hand,for the uniform matroid decision problem,an asymptotically optimal quantum algorithm is proposed which achieves the lower bound,and for the girth problem,an almost optimal quantum algorithm is given with query complexityO■.In addition,for the paving matroid decision problem,a lower boundΩ■on the query complexity is obtained,and an O■ quantum algorithm is presented.

关键词： quantum computing matroid quantum algorithm quantum query complexity