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In-process adaptive milling for large-scale assembly interfaces of a vertical tail driven by real-time vibration data

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Chinese Journal of Aeronautics 2022年第5期35卷 441-454页

作者： xiong zhao Lianyu ZHENG Lu YU School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China C919 Division Shanghai Aircraft Manufacturing Co.LtdShanghai 201324China

Assembly interfaces,the joint surfaces between the vertical tail and rear fuselage of a large aircraft,are thin-wall *** machining quality are seriously restricted by the machining *** address this problem,an in-process adaptive milling method is proposed for the large-scale assembly interface driven by real-time machining vibration *** this context,the milling operation is first divided into several process steps,and the machining vibration data in each process step is separated into some data ***,based on the real-time machining vibration data in each data segment,a finite-element-unit-force approach and an optimized space–time domain method are adopted to estimate the time-varying in-operation frequency response functions of the assembly *** FRFs are in turn employed to calculate stability lobe ***,the three-dimensional stability lobe diagram considering material removal is acquired via interpolation of all stability lobe ***,to restrain milling chatter and resonance,the cutting parameters for next process step,e.g.,spindle speed and axial cutting depth,are optimized by genetic ***,the proposed method is validated by a milling test of the assembly interface on a vertical tail,and the experimental results demonstrate that the proposed method can improve the machining quality and efficiency of the assembly interface,i.e.,the surface roughness reduced from 3.2μm to 1.6μm and the machining efficiency improved by 33%.

关键词： Adaptive milling Assembly interfaces Data-driven Time-varying frequency response function Vertical tail

B(LF,ω～2 )-refinability of inverse limits

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Applied Mathematics(A Journal of Chinese Universities) 2010年第4期25卷 496-502页

作者： xiong zhao-hui YANG Ming-quan Department of Mathematics Zhejiang Sci-Tech University Hangzhou 310018 China Department of Mathematics Jiaxing College Jiaxing 314001 China

Let X be the limit of an inverse system {Xα, παβ, ∧} and and let λ be the cardinal number of A. Assume that each projection πα ： X → Xα is an open and onto map and X is A-paracompact. We prove that if each Xα is B（LF, ω^2）-refinable （hereditarily B（LF, ω^2）- refinable）, then X is B（LF, ω^2）-refinable （hereditarily B（LF,ω ^2）-refinable）. Furthermore, we show that B（LF, ω^2）-refinable spaces can be preserved inversely undcr closed maps.

关键词： Inverse limit B(LF ω^2)-refinability hereditary B(LF,ω ^2)-refinability.

Male larval experience of cues from adult rivals alters lifetime sperm investment patterns in a sperm heteromorphic moth, Ephestia kuehniella

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Insect Science 2023年第6期30卷 1773-1783页

作者： Junyan Liu xiong zhao He Qiao Wang School of Agriculture and Environment Massey UniversityPalmerston NorthNew Zealand

Male animals may adjust their resource allocations for reproduction and other fitness functions in response to cues from rivals. For instance, adult males increase their investment in sperm for a higher paternity share when they perceive sperm competition risk in their surroundings. In nature, both juveniles and adults may coexist spatially and temporally. Yet, it is not clear how juvenile males of different ages respond to cues from adult rivals and fine-tune their lifetime investment in sperm production and ejaculation in any insect. Here we used the Mediterranean flour moth, Ephestia kuehniella, which produces both fertile eupyrene and infertile apyrene sperm, to explore this question. We demonstrate that the late, but not early, instar larvae are sensitive to adult male cues. As a response, they produce more sperm before emergence and their resultant adults have shorter mating latency and ejaculate more sperm in the first few matings. When the juvenile stage produces more eupyrenes, the adult stops making these sperm, but regardless of the number of apyrenes produced during the juvenile stage, the adult continues to make them. These findings suggest that the number of spermatogonia for eupyrenes may be limited and that for apyrenes may be flexible. Our results show that the insect does not trade off survival, mating frequency, body size, or testis size for sperm production in response to adult males during the larval stage. Knowledge created in the present study offers insight into the stage-dependent sensitivity of juvenile males to cues from adult rivals and subsequent lifetime resource allocations.

关键词： immature stage Lepidoptera spermatogenesis sperm allocation sociosex-ual environment

Conspecific cues mediate habitat selection and reproductive performance in a haplodiploid spider mite

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Current Zoology 2024年第6期70卷 795-802页

作者： Nuwan Weerawansha Qiao Wang xiong zhao He School of Agriculture and Environment Massey UniversityPrivate Bag 11222Palmerston North4472New Zealand Faculty of Animal Science and Export Agriculture Uva Wellassa University of Sri LankaPassara RoadBadulla 90000Sri Lanka

Selection of a suitable habitat by animals before settlement is critical for their survival and *** silk-spinning arthropods like spider mites,denser webs offer protection from predation and serve as a dispersal *** in habitats with the presence of conspecifics and silk webs can benefit the habitat-searching *** and conspecifics usually coexist,but their distinct effects on female colonization have received little *** this study,we used a haplodiploid spider mite,Tetranychus ludeni Zacher(Acari:Tetranychidae),to examine the impact of conspecific cues,including cues from ovipositing conspecifics and silk,on habitat selection and subsequent reproductive performance of *** show that females significantly preferred habitats with cues from neighboring conspecifics and silk and neighboring conspecifics induced additive effect to that of silk on habitat *** cues did not boost female reproduction but facilitated females laying larger eggs that were more likely to be fertilized and to develop into *** given a choice between silk-covered and clean habitats,females preferred silk-covered habitats,laid a similar number of eggs with similar size,but produced more daughters,suggesting that *** females can adjust the size threshold for fertilization in response to the current social *** of this study improves our understanding of spider mite habitat selection and post-settlement reproductive performance behaviors.

关键词： conspecifc cues habitat selection reproduction sex allocation

Unique Cobb syndrome with Kaposi hemangioendothelioma/tufted angioma as dominant phenotype:a case report

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World Journal of Pediatric Surgery 2023年第4期6卷 285-287页

作者： Na Lin xiong zhao Department of Burn and Plastic Surgery Children's HospitalZhejiang University School of MedicineHangzhouChina

Cobb syndrome,a neurocutaneous disease that is not widely recognized,is characterized by vascular anomalies involving the skin and spinal cord at the same metamere.12 Cobb syndrome can be accompanied by various clinical phenotypes of vascular anomalies,of which spinal arteriovenous malformations(AVMs)are the most widely mentioned in previous studies.3-5 Due to its rarity,the clear diagnostic criteria,incidence,and pathogenesis of Cobb syndrome are still unclear.

关键词： Kaposi clinical pathogenesis

Design of Vegetable Pot Seedling Pick‑up Mechanism with Planetary Gear Train

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Chinese Journal of Mechanical Engineering 2020年第4期33卷 87-97页

作者： Zhipeng Tong Gaohong Yu xiong zhao Pengfei Liu Bingliang Ye Zhejiang Province Key Laboratory of Transplanting Equipment and Technology Zhejiang Sci-Tech UniversityHangzhou 310018China Faculty of Mechanical Engineering&Automation Zhejiang Sci-Tech UniversityHangzhou 310018China

It has been challenging to design seedling pick-up mechanism based on given key points and trajectories,because it involves dimensional synthesis and rod length *** this paper,the dimensional synthesis of seedling pickup mechanism with planetary gear train was studied based on the data of given key points and the trajectory of the endpoint of seedling pick-up *** the positions and orientations requirements of the five key points,the study first conducted a dimensional synthesis of the linkage size and center of *** next steps were to select a reasonable solution and optimize the data values based on the ideal seedling *** link motion was driven by the planetary gear train of the two-stage *** pitch curves of noncircular gears were obtained by calculating and distributing the transmission ratio according to the *** the pitch curve with two convex points,the tooth profile design method of incomplete noncircular gear was *** seedling pick-up mechanism was tested by a virtual prototype and a physical prototype designed with the obtained parameter *** results were consistent with the theoretical design requirements,confirming that the mechanism meets the expected requirements for picking seedlings *** paper presents a new design method of vegetable pot seedling pick-up mechanism for an automatic vegetable transplanter.

关键词： Combined incomplete noncircular gear Mechanism dimension synthesis Planetary gear train Seedling pick-up mechanism

Automatic Scallion Seedling Feeding Mechanism with an Asymmetrical High-order Transmission Gear Train

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Chinese Journal of Mechanical Engineering 2020年第1期33卷 148-161页

作者： xiong zhao Jun Ye Mengyan Chu Li Dai Jianneng Chen Faculty of Mechanical Engineering and Automation Zhejiang Sci-Tech UniversityHangzhou 310018China Key Laboratory of Zhejiang Transplanting Equipment Technology Zhejiang Sci-Tech UniversityHangzhou 310018China

The current automatic scallion-transplanting machine is a complicated mechanism composed of two linkage mechanisms and two band *** delivers seedlings ine ciently because of the movement limitations of the linkage *** paper proposes a new high-order non-circular gear train for an automatic scallion-seedling feeding *** proposed gear train has an asymmetrical transmission ratio;i.e.,its transmission ratio *** allows the mechanism’s execution component to move in a long displacement and rotate in a large rotation *** long displacement enables the execution component to reach the designed working position,and the large rotation angle allows it to feed a scallion in the required pose.A mathematical model for calculating the asymmetrical transmission ratio was established according to the closure requirements and the full-cycle motion of the driven gear pitch ***,the parameter-design model of the new seedling-feeding mechanism was established,based on precise pose points and trajectory-shape control ***,an aided-design program was developed to obtain the parameter-solution domain of the scallion-seedling feeding *** mechanism parameters,which met the seedling-feeding function,were optimized to determine the transmission ratio,using a program and a kinematic ***,a prototype of the mechanism was produced,and a seedling-feeding experiment was carried ***-thousand seedlings were tested at a rate of 100 seedlings per minute,and the statistical success rate was 93.4%.Thus,the automatic scallion-seedling feeding mechanism significantly improves the e ciency of automatically transplanting scallions.

关键词： Asymmetric transmission Scallion transplanting High-order gear Non-circular gear Planetary gear train

Techno-economic evaluation of oxy-combustion coal-fired power plants

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Chinese Science Bulletin 2011年第31期56卷 3333-3345页

作者： xiong Jie zhao HaiBo ZHENG ChuGuang State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 430074 China

Increasing attention is being paid to the oxycombustion technique of coal-fired power plants because CO 2 produced from fossil fuel combustion can be captured and sequestrated by it. However, there are many questions about the economic properties of the oxy-combustion technique. In this paper, a detailed techno-economic evaluation study was performed on three typical power plants (2 × 300 MW subcritical, 2 × 600 MW supercritical, 2 × 1000 MW ultra supercritical), as conventional air fired and oxycombustion options in China, by utilizing the authoritative data published in 2010 for the design of coal-fired power plants. Techno-economic evaluation models were set up and costs of electricity generation, CO 2 avoidance costs as well as CO 2 capture costs, were calculated. Moreover, the effects of CO 2 tax and CO 2 sale price on the economic characteristics of oxycombustion power plants were also considered. Finally, a sensitivity analysis for parameters such as coal sample, coal price, air separation unit price, flue gas treatment unit price, CO 2 capture efficiency, as well as the air excess factor was conducted. The results revealed that: (1) because the oxy-combustion technique has advantages in thermal efficiency, desulfurization efficiency and denitration efficiency, oxy-combustion power plants will reach the economic properties of conventional air fired power plants if, (a) the CO 2 emission is taxed and the high purity CO 2 product can be sold, or (b) there are some policy preferences in financing and coal price for oxy-combustion power plants, or (c) the power consumption and cost of air separation units and flue gas treatment units can be reduced; (2) from subcritical plants to supercritical and finally ultra-supercritical plants, the economics are improving, regardless of whether they are conventional air fired power plants or oxy-combustion power plants.

关键词：技术经济评价富氧燃烧燃煤电厂空气分离装置二氧化碳税二氧化碳排放量氧燃烧技术发电成本

GLOBAL CONVERGENCE OF A CAUTIOUS PROJECTION BFGS ALGORITHM FOR NONCONVEX PROBLEMS WITHOUT GRADIENT LIPSCHITZ CONTINUITY

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Acta Mathematica Scientia 2024年第5期44卷 1735-1746页

作者： Gonglin YUAN xiong zhao Jiajia YU School of Mathematics and Information Science Center for Applied Mathematics of Guangxi(Guangxi University)Guangxi UniversityNanning530004China

A cautious projection BFGS method is proposed for solving nonconvex unconstrained optimization *** global convergence of this method as well as a stronger general convergence result can be proven without a gradient Lipschitz continuity assumption,which is more in line with the actual problems than the existing modified BFGS methods and the traditional BFGS *** some additional conditions,the method presented has a superlinear convergence rate,which can be regarded as an extension and supplement of BFGS-type methods with the projection ***,the effectiveness and application prospects of the proposed method are verified by numerical experiments.

关键词： cautious BFGS nonconvex problems Lipschitz continuity projection technique global convergence