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Chinese Journal of Aeronautics 2010年第6期23卷 707-714页

作者： ZhuYongguo huang Xiang fang Wei Li Shuanggao Department of Mechanical and Electrical Engineering Nanjing University of A eronautics and Astronautics Nanjing 210016 China Aeronautical Manufacturing Technology Institute Shanghai Aircraft Manufacturing Co. Ltd. Shanghai 200436 China

A 6-degree of freedom （6-DOF） aircraft wing position and pose automatic adjustment method is presented to improve ARJ21 wing-fuselage connection precision and efficiency. Wing position and pose are adjusted by three pillars which are driven by six high-precision servo motors. During the adjustment process, wing is tracked and positioned by laser tracker. Wing initial position and pose are calibrated by using the measurement coordinates of assembly reference points. Wing target position and pose are calculated according to wing initial, fuselage position and pose, and relative position and pose requirements between wing and fuselage for the connection. Combining Newton-Euler method with quaternion position and pose analyzing method, the inverse kinematics of servo motors, together with the adjustment system dynamics is obtained. Wing quintic polynomial trajectory planning algorithm based on quatemion is proposed; the initial, target position and pose need to be solved and the intermediate moving path is uncertain. Simulation results show that the adjustment method has good dynamic characteristics and satisfies engineering requirements. Preliminary engineering application indicates that ARJ21 wing adjustment efficiency and precision are improved by using the proposed method.

关键词： aircraft assembly calibration position and pose adjustment trajectory planning quaternion

Simulation of γ spectrum-shifting based on the parameter adjustment of Gaussian function space

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Nuclear Science and Techniques 2013年第6期24卷 99-104页

作者： huang Hongquan SHAO qiang DING Weicheng fang fang GONG Dichen Applied Nuclear Techniques in Geosciences Key Laboratory of Sichuan Province Chengdu University of Technology Drilling Engineering Research institute of southwest Petroleum Engineering Company SINOPEC

Based on the statistical characteristics of energy spectrum and the features of spectrum-shifting in spectrometry,the parameter adjustment method of Gaussian function space was applied in the simulation of *** transient characteristics of energy spectrum were described by the Gaussian function space,and then the Gaussian function space was transferred by parameter adjustment ***,the spectrum-shifting in measurement of energy spectrum was *** applied example shows that the parameters can be adjusted flexibly by this method to meet the various requirements in simulation of energy *** method was one parameterized simulation method with good performance for the practical application.

关键词：高斯函数参数调整空间仿真基础 γ谱仿真应用函数空间模拟方法

OPTIMAL ERROR ESTIMATES OF THE PARTITION OF UNITY METHOD WITH LOCAL POLYNOMIAL APPROXIMATION SPACES

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Journal of Computational Mathematics 2006年第3期24卷 365-372页

作者： Yun-qing huang Wei Li fang Su Hunan Key Laboratory for Computation and Simulation in Science and Engineering Institute for Computational and Applied Mathematics Xiangtan University Xiangtan 4 11105 China Department of Computational Science Xiangtan University Xiangtan 4 11105 China

In this paper, we provide a theoretical method（PUFEM）, which belongs to the analysis of the partition of unity finite element family of meshfree methods. The usual error analysis only shows the order of error estimate to the same as the local approximations[12]. Using standard linear finite element base functions as partition of unity and polynomials as local approximation space, in l-d case, we derive optimal order error estimates for PUFEM interpolants. Our analysis show that the error estimate is of one order higher than the local approximations. The interpolation error estimates yield optimal error estimates for PUFEM solutions of elliptic boundary value problems.

关键词： Meshless methods Partition of unity finite element method(PUFEM) Error estimate.

New insights into different surfactants’impacts on sludge fermentation:Focusing on the particular metabolic processes and microbial genetic traits

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Frontiers of Environmental Science & Engineering 2022年第8期16卷 221-234页

作者： Jingyang Luo Shiyu fang Wenxuan huang Feng Wang Le Zhang fang fang Jiashun Cao Yang Wu Dongbo Wang Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of EducationHohai UniversityNanjing 210098China College of Environment Hohai UniversityNanjing 210098China State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and EngineeringTongji UniversityShanghai 200092China College of Environmental Science and Engineering Hunan UniversityChangsha 410082China

Surfactants were expected to exhibit positive effects on the waste activated sludge(WAS)***,the systematic comparison of different categories of surfactants on the WAS fermentation and the functional mechanisms,especially microbial metabolic traits,have not yet been precisely *** study revealed the positive effects of different surfactants on the volatile fatty acid(VFA)production,which followed the order of alkyl polysaccharides(APG)>sodium dodecylbenzene sulfonate(SDBS)>hexadecyl trimethyl ammonium bromide(HTAB).Mechanistic exploration found that the presence of different surfactants improved solubilization and hydrolysis steps,and then contributed to the subsequent acidification with different *** functional microorganisms associated with VFA generation were enriched in surfactant-conditioned *** analysis further indicated that the key genes involved in the particular process of VFA generation were *** simultaneous bioavailable substrate improvement,functional bacterial enrichment,and metabolic activity upregulation induced by different surfactants jointly contributed to VFA promotion during WAS *** study could provide a comprehensive realization of surfactants’impacts on theWAS fermentation process,and more importantly,it reminded the public to discern the distinct interplaying effects induced by different chemicals in regulating the WAS disposal and resource recovery.

关键词： Waste activated sludge(WAS) Volatile fatty acids(VFA) Surfactant types Functional microorganisms Metabolic activity upregulation

Optimization Transmission Theory and Technical Pathways that Describe Multiscale Urban Agglomeration Spaces

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Chinese Geographical Science 2018年第4期28卷 543-554页

作者： fang Chuanglin YANG Junyan fang Jiawen huang Xiejun ZHOU Yi Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences School of Architecture Southeast University School of Public Policy University of Southern California College of Resources and Environmental Engineering Wuhan University of Technology Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences

Urban agglomerations are spatial entities that promote the development of ‘new urbanization' processes within China. In this context, the concept of ‘multiscale urban agglomeration spaces' encompasses three linked levels: macroscale urban agglomerations, mesoscale cities, and microscale urban centers. Applying a series of multidisciplinary integrated research methods drawn from geography, urban planning, and architecture, this paper reveals two intensive utilization laws that can be generalized to apply to multiscale urban agglomeration spaces, top-to-bottom ‘positive transmission' linkage and inside-to-outside ‘negative transmission' movement. This paper also proposes optimization transmission theory and policy decision technical pathways that can be applied to these three urban agglomeration spatial scales. Specific technical pathways of transmission include intensive expansion and simulated decision-making in macroscale urban agglomerations, ecology, production, and living space intensive layout and dynamic decision-making in mesoscale cities, and four cores(i.e., ‘single, ring, axis, and pole core') progressive linkage and intensive optimization decision-making in microscale urban centers. The theory and technical pathways proposed in this paper solve the technical problem of optimization and provide intensive methods that can be applied not only at the individual level but also at multiple scales in urban agglomeration spaces. This study also advances a series of comprehensive technical solutions that can be applied to both compact and smart growth cities as well as to urban agglomerations. Solid theoretical support is provided for the optimization of Chinese land development, urbanization, agricultural development, and ecological security.

关键词： urban agglomeration optimization transmission theory of multiscale urban spaces intensive space utilization technicalpathways

Partial melting of the dry mafic continental crust: Implications for petrogenesis of C-type adakites

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Chinese Science Bulletin 2010年第22期55卷 2428-2439页

作者： huang fang HE YongSheng Institute of Geochemistry and Petrology ETH Zurich 8092 Zurich Switzerland CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China

C-type adakites have been commonly considered as a result of partial melting of the mafic lower continental crust (LCC) at high pressure, as supported by high P-T experiments on hydrous basalts. However, because the mafic eclogitic LCC is generally dry, experiments on water-bearing materials cannot be used to constrain the melting processes of the dry mafic LCC. Due to the lack of systematic melting experimental studies on dry mafic rocks at crustal pressures, MELTs software was applied to simulating melting of the dry mafic LCC at 1–2 GPa. Comparison of model results with experimental data indicates that, when melting de-gree is greater than 20%, melts from the dry mafic LCC at 1–3 GPa cannot produce the C-type adakitic melt with high SiO2 con-tent (～70%). Although the limited experimental results about dry mafic rock melting at 1–2 GPa in the literature suggest that low degree melting (1.8 GPa, low-degree melting can produce dacitic melt with high K2O/Na2O (～1) if SiO2 content of the melt is controlled by residual garnet. Furthermore, the simulation also suggests that, if pressure is <1.8 GPa, abundant plagioclase (plg) in the residual phase may de-crease SiO2 content in the melt to below 62%, much lower than that of the C-type adakites observed in eastern China. Given the high P-T conditions required to produce melts with high SiO2 and extremely low HREE contents, such melts could easily be con-taminated by other crustal-derived melts, implying that the C-type adakites from eclogite melting could be less commonly ob-served in the outcrops than previously believed. Besides the interpretation that garnet fractionates Sr, Y, and REE, high Sr/Y and La/Yb could be also produced by multiple ways such as inheriting the source features and fractional crystallizing clinopyroxene (cpx). Therefore, it may be problematic using high Sr/Y and La/Yb as criteria to identify adakites. Ins

关键词： C型埃达克岩镁铁质下地壳部分熔融基性岩高温高压实验 SiO2含量成因高温高压条件

Late Quaternary Calcareous Nannofossils from the Offshore Sediments in southern Hongkong

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Acta Geologica Sinica(English Edition) 1999年第2期73卷 242-247页

作者： huang Yongyang CHEN fang Guangzhou Marine Geological Survey MGMR Guangzhou 510075

Abstract Based upon the features of nannofossil composition, distribution, abundance and diversity, the fossil-bearing sediments exposed by five drill holes in the offshore area of southern Hongkong can be divided into the upper Middle Pleistocene, the Upper Pleistocene and Holocene. There were two palaeoclimatic stages in the Holocene in this area according to fossil palaeoecologic and sedimentation analyses: the temperature-rising stage and the warm stage. The latter involves two temperature-falling periods, which could be the major factor causing sea-level fall during that time.

关键词： nannofossil Quaternary palacooceanography Lingdingyang southern Hongkong

Constitutive modelling of concrete material subjected to low-velocity projectile impact:insights into damage mechanism and target resistance

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第2期25卷 161-182页

作者： Shen LIU Xieping huang Xiangzhen KONG Qin fang Center for Hypergravity Experiment and Interdisciplinary Research Zhejiang UniversityHangzhou310058China Institute of Geotechnical Engineering Zhejiang UniversityHangzhou310058China State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing210007China

This paper presents a numerical study to improve the understanding of the complex subject of penetration and perforation of concrete targets impacted by low-velocity *** main focus is on the damage mechanisms and the major factors that account for the target resistance of the *** improved continuous surface cap model recently proposed was *** model was first equipped with element erosion criteria and was adequately validated by comparisons with ballistic *** numerical simulations were carried out where the individual influence of tensile,shear,and volumetric behaviors(pore collapse)of a concrete target on its ballistic performance was *** demonstrated that cratering on the front face and scabbing on the rear face of the concrete target were mainly dominated by its tensile *** major target resistance came from the second tunneling stage which was primarily governed by the shear and volumetric behaviors of the ***,this study captured the pore collapse-induced damage phenomenon during the high-pressure tunneling stage,which has been extensively reported in experiments but has usually been neglected in previous numerical investigations.

关键词： Penetration Perforation Damage mechanism Target resistance Projectile impact Pore collapse

Phase transition of bastnaesite concentrate in calcification process

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Rare Metals 2016年第8期35卷 649-654页

作者： Yu-Kun huang Ting-An Zhang Zhi-He Dou Jiang Liu fang-fang Tang Key Laboratory of Ecological Metallurgy of Multi-Metal Intergrown Ores of Ministry of Education School of Materials and Metallurgy Northeastern University

The phase transformation in calcification process was investigated by X-ray diffraction （XRD） and differential scanning calorimeter （DSC）, and the effect of calcification on the leaching rate of rare earth was analyzed. The results show that bastnaesite transforms into rare earth hydrate at the cal- cification temperature range of 225-300 ℃. However, this transition is verified to be an efficient reaction for the acti- vating bastnaesite when the temperature is higher than 200 ℃. The leaching rate of rare earth increases to 89.17 % for activating bastnaesite from 36.27 % for the bastnaesite, and it is the highest with calcification temperature of 250 ℃, which is consistent with the result of DSC analysis. The transition of rare earth oxyfluoride into RE（OH）3 is acceler- ated by the addition of NaOH according to the experiments of different calcification systems.

关键词： Bastnaesite Calcification transformation Solidfluoride reaction Mineral phase transition

Dynamic measurements of serum inhibin B and estradiol: a predictive evaluation of ovarian response to gonadotrophin stimulation in the early stage of IVF treatment

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第1期10卷 35-45页

作者： Ming-fang MIAO He-feng huang Department of Reproductive Endocrinology Women's Hospital School of Medicine Zhejiang University Hangzhou 310006 China

Objective： We dynamically measured serum inhibin B and estradiol in the early stage of hormonal stimulation to predict the ovarian response in in vitro fertilization （IVF） treatment. Methods： A total of 57 patients （〈40 years of age） who underwent the first cycle of long protocol IVF or introcytoplasmic sperm injection （ICSI） treatment were included. Serum inhibin B, estradiol, follicle stimulating hormone （FSH） and luteinizing hormone （LH） levels were measured four times：（1） on Day 3 of the menstrual cycle （basal）; （2） on the day before the first administration ofgonadotrophin （Gn）（Day 0）; （3） on Day 1 of Gn therapy; and （4） on Day 5 of Gn therapy. Comparisons of these measurements with ovarian responses and pregnancy outcomes were made and analyzed statistically. Results：（1） On Day 1 and Day 5 of recombinant FSH （rFSH） stimulation, ovarian response, i.e., numbers of follicles, oocytes, fertilized oocytes, and embryos, had a positive correlation （rs=0.46-0.61, P 0.000） with raised inhibin B and estradiol concentrations, but a negative correlation （rs=-0.67--0.38, P=0.000 or P〈0.01） with total rFSH dose and total days ofrFSH stimulation. （2） No significant variation （P〉0.05） between the pregnant and non-pregnant groups on the basis of mean age or on all hormone concentrations at four times of the IVF cycle was observed. However, all the seven patients aged 〉35 years did not reach pregnancy. Conclusions：（1） Serum inhibin B and estradiol concentrations obtained shortly after Gn therapy may offer an accurate and early prediction of ovarian response; （2） Low levels of serum inhibin B and estradiol obtained shortly after Gn stimulation indicate the need for a longer period of Gn treatment and a higher daily dosage; （3） No obvious pregnancy difference among patients of age 〈35 years was found; however, IVF pregnancy outcome is significantly lower in women of age 〉35 years.

关键词： Inhibin B Estradiol Ovarian response In vitro fertilization (IVF) Pregnancy