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| 1 | Variation character of stagnation point heat flux for hypersonic pointed bodies from continuum to rarefied flow states and its bridge function study显示文摘This paper is a research on the variation character of stagnation point heat flux for hypersonic pointed bodies from continuum to rarefied flow states by using theoretical analysis and numerical simulation methods. The newly developed near space hypersonic cruise vehicles have sharp noses and wingtips,which desires exact and relatively simple methods to estimate the stagnation point heat flux. With the decrease of the curvature radius of the leading edge,the flow becomes rarefied gradually,and viscous interaction effects and rarefied gas effects come forth successively,which results in that the classical Fay-Riddell equation under continuum hypothesis will become invalid and the variation of stagnation point heat flux is characterized by a new trend. The heat flux approaches the free molecular flow limit instead of an infinite value when the curvature radius of the leading edge tends to 0. The physical mechanism behind this phenomenon remains in need of theoretical study. Firstly,due to the fact that the whole flow regime can be described by Boltzmann equation,the continuum and rarefied flow are analyzed under a uniform framework. A relationship is established between the molecular collision insufficiency in rarefied flow and the failure of Fourier's heat conduction law along with the increasing significance of the nonlinear heat flux. Then based on an inspiration drew from Burnett approximation,control factors are grasped and a specific heat flux expression containing the nonlinear term is designed in the stagnation region of hypersonic leading edge. Together with flow pattern analysis,the ratio of nonlinear to linear heat flux Wr is theoretically obtained as a parameter which reflects the influence of nonlinear factors,i.e. a criterion to classify the hypersonic rarefied flows. Ultimately,based on the characteristic parameter Wr,a bridge function with physical background is constructed,which predicts comparative reasonable results in coincidence well with DSMC and experimental data in the whole flow regime. | WANG ZhiHui BAO Lin TONG BingGang | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，12： | 6 |
| 2 | Mass and performance optimization of an airplane wing leading edge structure against bird strike using Taguchi-based grey relational analysis显示文摘Collisions between birds and aircraft are one of the most dangerous threats to flight safety. In this study, smoothed particles hydrodynamics(SPH) method is used for simulating the bird strike to an airplane wing leading edge structure. In order to verify the model, first, experiment of bird strike to a flat aluminum plate is simulated, and then bird impact on an airplane wing leading edge structure is investigated. After that, considering dimensions of wing internal structural components like ribs, skin and spar as design variables, we try to minimize structural mass and wing skin deformation simultaneously. To do this, bird strike simulations to 18 different wing structures are made based on Taguchi's L18 factorial design of experiment. Then grey relational analysis is used to minimize structural mass and wing skin deformation due to the bird strike. The analysis of variance(ANOVA) is also applied and it is concluded that the most significant parameter for the performance of wing structure against impact is the skin thickness. Finally, a validation simulation is conducted under the optimal condition to show the improvement of performance of the wing structure. | Hassan Pahange Mohammad Hossein Abolbashari | 2016 | Chinese Journal of Aeronautics2016，29，4： | 6 |
| 3 | Application of shear-sensitive liquid crystal coating to visualization of transition and reattachment in compressor cascade显示文摘The present paper aims at introducing Shear-Sensitive Liquid Crystal Coating(SSLCC)technology into compressor cascade measurement for the first time and serves as a basis for better understanding of the influence from the boundary layers. Optical path layout, which is the most significant difficulty in internal flow field measurement, will be solved in this paper by selfdesigned image acquisition device. Massive experiments with different Mach number and incidence are conducted at a continuous subsonic cascade wind tunnel to capture the boundary layer phenomenon. Image processing methods, such as Three-Dimensional(3-D) reconstruction and Hue conversion, are used to improve the accuracy for transition position detection. The analysis of the color-images indicates that complex flow phenomena including transition, flow separation,and reattachment are captured successfully, and the effect of Mach number and incidence on the boundary layer flow is also discussed. The results show that: the Mach number has a significant effect on transition position; the incidence has little effect on transition position, but it has a great impact on the transition distance and leading-edge separation; influenced by the end-walls, the reattachment occurs in advance under positive angle of attack conditions. | Ruiyu LI Limin GAO Shuai ZHANG Yongzeng LI Tianyu GAO | 2018 | Chinese Journal of Aeronautics2018，31，11： | 4 |
| 4 | Role of behavioral training in reducing functional impairments after stroke显示文摘Stroke is the leading cause of long-term disability worldwide.There are two main types of stroke,hemorrhagic and ischemic.A hemorrhagic stroke is when there a bleed in the brain,whereas an ischemic stroke is the result of blockage of blood flow to the brain,which leads to degeneration,neurotoxicity,inflammation,and apoptosis.This damage not only affects the ischemic core,but also neuronal,astrocyte,and synaptic survival in the peri-infarct region and connected areas(Kerr et al.,2011;Jadavji et al.,2018).The prevalence of ischemic stroke is predicted to increase as the global population ages(Mukherjee and Patil,2011).Between 1970 and 2008 there has been a 100%increase in stroke incidence in low income countries.For example,the estimated losses in gross domestic product,as the result of vascular diseases,including stroke,have ranged from$20 million in Ethiopia to$1 billion in China and India(Mukherjee and Patil,2011). | Mahira Moftah Nafisa M.Jadavji | 2019 | Neural Regeneration Research2019，14，9： | 4 |
| 5 | Maltivariate Analysis of the Occurring Process of Skeletonema costatum Red Tide in the Changjiang Estuary显示文摘Using the SAS software, the data of environmental factors vs. red tide biomass were analysed during the process of Skeletonema costatum red tide which broke out in the Changjiang Estuary on June 9~15, 1990. The results of the multivariate statistical analysis show that the environmental factors are similar in their developing and maintenance periods and that the values of environmental factors begin to be restored to normal levels during the disappearing period.The results obtained from using the methods of correlation, variable cluster and main component analyses are basically identical. The important factors contributing to the occurrence of this red tide are atmospherical pressure, water temperature, salinity, pH, No3-, -N, Po43--P and Fe, among which,salinity, Fe and PO43--P are the leading factors which have triggered the occurrence of the red tide as determined by the step-by-step regression analysis. Meanwhile, the linear discrimination functions have been established for the red tide. The environmental factor data of another occurring process of Skeletonema costatum red tide in the Changjiang Estuary have been chosen for red tide discrimination with satisfactory results. | 黄秀消 蒋晓山 陶然 洪君超 | 2001 | Marine Science Bulletin2001，3，1： | 3 |
| 6 | Numerical studies of reverse flows controlled by undulating leading edge显示文摘The improved delayed detached-eddy simulation(IDDES) method is used to simulate the reverse flows past an NACA0012 airfoil at medium(10°) and large(30°) angles of attack. The numerical results of the baseline configuration are compared with the available measurements. The effects of the undulating leading edge with four different amplitudes are compared and analyzed at angle of attack of 10°. Based on these analyses, the amplitude of A/C=0.04 yields the best performance. Compared with the uncontrolled case, the performances of the undulating leading edge are greatly improved with reducing of the aerodynamic fluctuations. Furthermore, the mechanisms of performance are explored by comparing the local flow structures near the undulations. | Biao Wang Jian Liu QiBing Li YunJun Yang ZhiXiang Xiao | 2019 | Science China(Physics,Mechanics & Astronomy)2019，62，7： | 2 |
| 7 | Oxidative Dehydrogenative [3+3] Annulation of Benzylhydrazines with Aziridines Leading to Tetrahydrotriazines显示文摘Oxidative dehydrogenative [3+3] annulation of benzylhydrazines with N-sulfonylaziridines is described.A series of complex tetrahydro-1,2,4-triazines were produced under mild reaction conditions. | Haitao Li Jia Liang Congde Huo | 2019 | Chinese Journal of Chemistry2019，37，9： | 2 |
| 8 | Effect of Leading-Edge Optimization on the Loss Characteristics in a Low-Pressure Turbine Linear Cascade显示文摘This paper presents a numerical study on the aerodynamics loss reduction characteristics after the leading-edge(LE) optimization in a low-pressure turbine linear cascade. The LE was optimized with a simple and practical method of 'Class Function/Shape Function Transformation Technique'(CST). The simulation conditions, covering the whole working range, were independently determined by incidence, Reynolds number and Mach number. Quantitative loss analyses were carried out with a loss breakdown method based on volumetric integration of entropy production rates. To understand the reason of loss reduction, the local sources at different operating points were identified with entropy production rates. The results showed that LE optimization with the CST method played a positive role in decreasing the total losses, and the working range with lower loss was extended. The profile loss and the endwall loss were significantly reduced by the LE optimization, which were also verified to be the major causes of the total loss reduction by loss breakdown. The decrease of profile loss can be attributed to the boundary layer near the LE region and the boundary layer of downstream at off-design incidence. The reduction mostly came from the pressure side at negative incidence, while came from the suction side at the positive incidence. The endwall loss was decreased markedly about 2.5%–5% by the LE optimization at the incidence of-12°, which was 1% at the incidence of 12°. The mechanism for the endwall loss reduction at different incidences was different from each other. At negative incidence, the LE optimization diminished the corner separation vortex on the pressure side. While at positive incidence, the benefits came from three aspects, i.e., reduced suction LE separation bubbles close to the endwall, reduced passage vortex strength, and weakened shear process between passage vortex and trailing shed vortex. The loss of the downstream zone was relatively lower than that of the profile losses and the endwall losses. The effect of LE optimization on the loss of the downstream zone at different conditions was complex and it depended both on the profile boundary layer behavior at the suction trailing edge and on the passage vortex strength. | CUI Tao WANG Songtao TANG Xiaolei WEN Fengbo WANG Zhongqi | 2019 | Journal of Thermal Science2019，28，5： | 1 |
| 9 | Overcoming the contradiction between promoting economic growth and transforming the economic growth pattern显示文摘Promoting economic growth has become the first and foremost objective of macro-control since China experienced a drastic economic downturn in the fourth quarter of 2008. Now China is at a special stage of transition characterized by the transformation of the economic growth mode. While promoting economic growth, the government must effectively coordinate the relationship between economic growth and the transformation of growth mode. This is not a task that can be done easily. To promote economic growth, the central government has selected a number of industries and formulated an industrial revitalization plan for each of these them. Revitalizing these industries helps promote economic growth at the present stage but propelling these industries alone still cannot fully meet the requirements for transforming the economic growth pattern. To coordinate the relationship between promoting economic growth and transforming the economic growth pattern, it is currently imperative to adjust China’s industrial upgrading strategy and to pay attention to intra-industrial upgrading, particularly process upgrading. | 张其仔 郭朝先 白玫 | 2009 | China Economist2009，4，4： | 1 |
| 10 | Therapeutic potential of AMPA receptor antagonist perampanel against cerebral ischemia: beyond epileptic disorder显示文摘Stroke is a leading cause of mortality and severe neurological disability worldwide;however,curative therapeutic options are limited.Although recanalization therapy using endovascular thrombectomy has demonstrated great benefits in the functional outcome of patients with acute ischemic stroke,the rate of excellent clinical outcomes remains limited.Therefore,the current recanalization therapeutic approach may require adjunctive therapy to improve outcomes. | Satoshi Suda Kazumi Kimura | 2019 | Neural Regeneration Research2019，14，9： | 1 |
| 11 | Numerical investigation on detonation cell evolution in a channel with area-changing cross section显示文摘The two-dimensional cellular detonation propagating in a channel with area-changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed chemical reaction model. Effects of the flow ex-pansion and compression on the cellular detonation cell were investigated to illus-trate the mechanism of the transverse wave development and the cellular detona-tion cell evolution. By examining gas composition variations behind the leading shock,the chemical reaction rate,the reaction zone length,and thermodynamic parameters,two kinds of the abnormal detonation waves were identified. To explore their development mechanism,chemical reactions,reflected shocks and rarefac-tion waves were discussed,which interact with each other and affect the cellular detonation in different ways. | DENG Bo,HU ZongMin,TENG HongHui & JIANG ZongLin Key Laboratory of High Temperature Gas Dynamics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100080,China | 2007 | Science China(Physics,Mechanics & Astronomy)2007，50，6： | 1 |
| 12 | Technology Innovation Mode of Agricultural Leading Enterprise——Based on the Virtual Organization Mode显示文摘Based on the definition of technology innovation of agricultural leading enterprises by domestic and foreign experts and scholars,technology innovation of agricultural enterprises is a process of new market increment,which uses new knowledge,technology,process and production mode,produces new products,offers new services and realizes commercialization. Characteristics of agricultural technology innovation are introduced,such as obvious regionality,relatively high risk,long-term periodicity and public attribute. Predicament for technology innovation of leading enterprises is analyzed,such as technical constraints,financial constraints and personnel constraints. Technological Innovation Mode can be classified into three modes of independent innovation,imitative innovation and cooperative innovation by the method of technology innovation. Among them,since there are some defects in the technology innovation process,independent innovation and imitative innovation are generally not used for the innovation of agricultural enterprises. Cooperative Innovation Mode can rely on foreign aid,can realize complementary advantages and achievement sharing,and can be widely applied in the agricultural innovation enterprise. Virtual organization in cooperation innovation mode is described,which makes up for technology,capital and human resources barriers in the process of agricultural enterprise innovation. Therefore,this mode is popular among the agricultural innovation enterprise. | CHEN Nian-hong1,2,CAO Jian1,2 1. Tang Ren Shen Group Co.,Ltd,Zhuzhou 413055,China 2. Beijing University of Agriculture,Beijing 102206,China | 2010 | Asian Agricultural Research2010，2，4： | 1 |
| 13 | Numerical Analysis and PIV Measurements of Tip Vortex in an Axial Rotor with Skewed-Swept Blade at Its Leading Edge显示文摘Based on the characteristics of axial fans of outdoor units of centralized air-conditioners, using the finite-volume method, applying three-dimensional steady Reynolds-averaged Navier-Stokes equations coupled with Spalart-Allmaras turbulence model equation, and adopting SIMPLE algorithm, numerical analysis is made and applied to analyze the internal flow field of axial rotors with skewed-swept blade at its leading edge. This numerical simulation mainly investigates the formation and development of the tip vortex. Based on the tip vortex characteristics that have been captured, the internal flow numerical results are compared with those obtained by the PIV experiments. This comparison indicates a good agreement between numerical results and PIV results, thus proving the validity of the numerical simulation. In addition, based on the internal flow analyses of the axial rotor with skewed-swept blade at its leading edge, different flow phenomena features are presented. These flow features can be used for further improvements of the present rotor performance characteristics. | Guanghui Wu Lijie Zheng Keqi Wu | 2004 | Journal of Thermal Science2004，13，1： | 1 |
| 14 | 昆廷·斯金纳:《从人文主义到霍布斯:修辞学与政治学研究》,剑桥:剑桥大学出版社,2018年版,432页(英文)显示文摘As one of the most influential and leading intellectual historians in the world,Quentin Skinner has offered a series of outstanding works centering on the history of early modern Europe for the past few decades.His early works on the Foundation of early modern political thought,and monographic studies on Machiavelli and Hobbes shaped the way a generation understands the political thought to a large extent,while his continuing engagement in methodological debates provides a new approach for students and fellow researchers to conduct the study of intellectual history. | 罗宇维 | 2018 | 国际比较文学(中英文)2018，1，2： | 0 |
| 15 | Using Leading Indicators to Improve Project Performance Measurement显示文摘Project performance measurement offers a wide range of methods to help project managers monitor projects.However,several critical issues remain in project performance measurement,such as an unbalanced use of indicators due to a lack of prediction-based (leading) indicators with regard to outcome-based (lagging) indicators.For its part,systems engineering measurement,although a more recent discipline,offers a wide variety of indicators,including a set of leading indicators.As our objective is to increase project performance and success rates,this involves improving project performance measurement on which project management decisions are based.This purpose,the proposal put forward in this paper is to extend the number and type of indicators used in project performance measurement by adapting the leading indicators defined in systems engineering measurement.The methodology involves first mapping the systems engineering indicators with the project management activities,resulting in identification of a set of potentially useful indicators for measuring the different activities,then tailoring a selection of these indicators with project-specific data to define a set of the most relevant indicators for a given project.This methodology is illustrated by means of a case study in a manufacturing company. | Li Zheng Claude Baron Philippe Esteban Rui Xue Qiang Zhang Shanlin Yang | 2019 | Journal of Systems Science and Systems Engineering2019，28，5： | 0 |
| 16 | Selection,distribution and way of development of leading industries in the Beijing-Kowloon economic belt显示文摘I.AssesmentoftheConditionsfortheDevelopmentofIndustriesintheBeijingKowloonEconomicBeltTheenvironmentalconditionsfortheeconom... | JIN Fengjun Institute of Geography, Chinese Academy of Sciences, Beijing 100101 CHINA | 1998 | Journal of Geographical Sciences1998，8，3： | 0 |
| 17 | Selection of Regional Leading Industry Based on Comparative Advantage——A Case of Xiqing District,Tianjin City,China显示文摘Development status of agricultural industry in Xiqing District of Tianjin City in China is introduced.The intensive level of agriculture is relatively high in this region;the new-type agriculture develops rapidly;and the sales income of agricultural byproducts is the main source of household income.Based on the principles of market potential,production resources intensity,and associated promotion,a total of 3 indices for measuring the comparative advantage are selected,which are comparative advantage index,scale advantage index,and comprehensive advantage index.Based on the data analysis,competitive industries in this region are determined.Result shows that economic crops and aquaculture industry have relatively great location quotient,but aquaculture is not suitable for Xiqing District,due to its natural condition,industrial tradition and bases,and output value.Therefore,economic crop is selected as the leading industry in Xiqing District. | QI Tian-zhen Department of Economic Management,Tianjin Agricultural University,Tianjin 300384,China | 2011 | Asian Agricultural Research2011，3，3： | 0 |
| 18 | Mechanisms and Processes Leading to Reverse Zoning in the Andong Granitoid Pluton, Andong Batholith, Korea显示文摘The Andong pluton consists of comagmatic granitoid rocks which constitute outstanding examples of reversely zoned granitoids. The pluton has three lithofacies: hornblende biotite tonalite, biotite granodiorite and porphyritic biotite granite. The zoned pattern forms by locating a tonalite core containing high-temperature mafic assemblages in central part,granodiorite rims in marginal part, and a porphyritic granite cap containing more felsic assemblages in topside of the pluton.Mineral abundances as well as bulk compositions of the granitoids indicate that the interior is enriched in mafic minerals and that it shows higher contents of oxides than the margin and topside. The compositional gradients change gradually with continuity between the lithofacies. The regular compositional variations within the pluton support the argument that the pluton behaved as an individual petrochemical system. Model abundances of the granitoids are in agreement with the bulk compositional gradients, suggesting that no significant interaction with country rocks occurred. Remobilization (resurgence) of deeper parts of the system into the more felsic magmas of the chamber explains the reverse zoning. Fractional crystallization was of importance and probably accounts for the selective removal of the settling phases. The Andong pluton is an example of reversely zoned plutons related by remobilization of more mafic but consanguineous magmas. Large-scale upwelling occurred in the pluton leading to the present arrangement of three lithofacies. It is conceivable that remnants of the reverse zoning become more difficult to discern as the plutonic rocks reach the latest stages of their evolution. In this case, the Andong pluton represents an earlier stage in the evolution of a felsic system that is usually represented by the final stages in normally zoned plutons. | Sang Koo HWANG | 2002 | Global Geology2002，7，2： | 0 |
| 19 | Nylon industry trend: What are the four leading companies doing?显示文摘In addition to low temperature resistance, nylon has outstanding characteristics in strength, wear resistance and moisture absorption, which makes nylon fabrics have great advantages in outdoor, sports, cold-proof, casual wear and other fields. At present, nylon has become the second largest chemical fiber after polyester in the textile field, accounting for 7.36% of the world’s total chemical fiber output. | | 2019 | China Textile2019，，7： | 0 |
| 20 | An analysis of leading factors during Skeletonema costatum bloom occurring process in Shengshan sea area显示文摘AnanalysisofleadingfactorsduringSkeletonemacostatumbloomoccurringprocessinShengshanseaarea￥HongJunchao;HuangXiuqing,;JiangXia... | Hong Junchao Huang Xiuqing, Jiang Xiaoshan and Wang GuilanEast China Sea MOnitndng Canter, State Oceanic (Administration, Shanghai 200137, China) | 1994 | Acta Oceanologica Sinica1994，13，3： | 0 |
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