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| 1 | Optimization of the head shape of the CRH3 high speed train显示文摘Aiming at optimizing the head shape of the CRH3 high speed train, an efficient optimization approach is proposed. The CFD analysis by solving Navier-Stokes equations is coupled with optimization calculation based on the multi-objective genetic algorithm, meanwhile the arbitrary shape deformation technique (ASD) is also introduced into the design flow, which greatly shortens the time consumption for geometry regeneration and flow field remeshing. As a result, the efficiency of the optimization calculation is highly improved. Statistical analysis is done to the designs in the design space, and the correlation between the design variables and the objective is studied to find out the key variables that most affect the objective. Response surface analysis is also performed to get the nonlinear relationship between the key design variables and the objective with the Kriging algorithm. Finally, after the optimization, an aerodynamic performance comparison between the optimal shape and the original shape reveals that the original shape of CRH3 high speed train owns a very stable aerodynamic performance and can be trustingly used in industry. | SUN ZhenXu1, SONG JingJing1 & AN YiRan1 College of Engineering, State Key Laboratory for Turbulence and Complex Systems, Peking University, Beijing 100871, China | 2010 | Science China(Technological Sciences)2010，53，12： | 35 |
| 2 | Characteristics of paleoflood deposits archived in unit T0403 of Yuxi Site in the Three Gorges reservoir areas,China显示文摘Based on the detailed analyses,multi-proxies such as AMS 14 C dating,grain size,component and morphology of heavy minerals,micromorphology of zircon,magnetic susceptibility,Rb/Sr and Hg content are used to research the paleoflood sediments archived in the Yuxi Site.The research indicates that, since 7.6 kaBP,at least 16 times of paleoflood with water level above Wusong Elevation 147.024 m(a.s.l.) left deposits in the Neolithic layers of unit T0403 from the Yuxi Site.The results are induced from the following aspects:(1)The plaeoflood sediments take on great similarities with modern flood sediments in the Yuxi Site and Zhongba Site in probability cumulative curves which mainly show a pattern of 3 segments in fluvial pattern.(2)There is some resemblance between the heavy mineral components and the zircon shape characteristics of paleoflood deposits and those of modern flood deposits.(3) Magnetic susceptibility values(40.44―70.10SI)are lower than those of sediments from cultural layers (59.59―188.68SI).(4)Hg values(290.71―742.51 ng/g)are lower than those of sediments from cultural layers(344.16―10518.17 ng/g).(5)Rb/Sr values are higher than those of sediments from cultural layers, while those of the 4th,5th,6th,7th,8th cultural layers are high,which shows that they are inundated by paleoflood.The reason for many flood deposits existing is related to the site situated on the first terrace where the Yuxi River joins with the Yangtze River.As there are some similarities between the plaeoflood sediments and those of the Zhongba Site,it is feasible to confirm the existence of paleoflood sediments based on the above points. | ZHU Cheng MA ChunMei XU WeiFeng BAI JiuJiang ZHENG ChaoGui ZHU GuangYao WANG HuiLin CHEN Ye LU XueFeng | 2008 | Chinese Science Bulletin2008，53，S1： | 16 |
| 3 | CuZnAl Shape Memory Alloy Refined with Composite Rare Earths La+Ce显示文摘The effects of composite rare earths La+Ce on properties of CuZnAl shape memory alloys were studied bymetallograph examination, tensile and bending tests, electric resistivity measurements, EDS and SEM. The test resultsshow that the grain size of CuZnAl shape memory alloys could be diminished effectively and the mechanical propertiesimproved obviously by the addition of composite rare earths La+Ce (La: Ce=1: 1). Meanwhile, the excellent shapememory properties remained unchanged. The results of microanalyses indicate that the composite rare earths were segregated at grain boundaries and impeded the grain growth, leading to the improvement of the mechanical properties ofCuZnAl alloys. If the amount of composite rare earths La+Ce was greater than 0. 10%, the shape memorial propertiesbecame poor. | 司乃潮 | 1999 | Journal of Rare Earths1999，17，4： | 16 |
| 4 | Experimental observation of the nano-scale particles in geogas matters and its geological significance显示文摘The geogas collectors showing a geogas anomaly in field geogas prospecting and in simulation tests were selected for the observation under high resolution microscopy. The result demonstrates that the geogas matter is transported in the form of nano scale particles with a size of about \%N\% nm to \%N\%·10 nm, and accumulated into aggregations of 1\2 μm to \%N\%·10 μm, with globular and film shape, and the component of Cu, Zn, Cr, Au, Al, V, Si, Br, Cl, S, Ca, etc. Based on the knowledge of nano science and technique, the mechanism of the geogas prospecting and its significance in geology and mineral prospecting are discussed. | 童纯菡 李巨初 葛良全 杨凤根 | 1998 | Science China Earth Sciences1998，41，3： | 15 |
| 5 | Selective laser melting of NiTi alloy with superior tensile property and shape memory effect显示文摘It is a challenge to develop complex-shaped Ni Ti shape memory alloy parts by traditional processing methods, due to the poor machinability of Ni Ti alloy. It is reported that selective laser melting(SLM) of additive manufacturing could overcome this problem. However, the reported SLM-produced Ni Ti exhibits poor tensile ductility due to the inner defects and adverse unidirectional columnar grains from SLM process. In this work, the defect-less SLM-Ni Ti with nondirective columnar grains was fabricated by optimizing the intraformational laser scanning length and interformational laser scanning direction. The obtained lath-shaped SLM-Ni Ti sample exhibits tensile strain of 15.6%, more than twice of the reported maximum result(7%). Besides, the SLM-Ni Ti part with complex geometry displays a shape memory recovery of 99% under compressive deformation of 50%. | Zhiwei Xiong Zhonghan Li Zhen Sun Shijie Hao Ying Yang Meng Li Changhui Song Ping Qiu Lishan Cui | 2019 | Journal of Materials Science & Technology2019，35，10： | 15 |
| 6 | Effect of erbium on properties and microstructure of Al-Si eutectic alloy显示文摘Eutectic Al-12.6 wt.%Si alloys with various contents of the rare earth element Er were prepared by the conventional casting technique. The effect of Er on the microstructure and properties of the eutectic Al-Si alloys was investigated using optical microscopy, scanning electron microscopy as well as the friction and wear tests. It was found that the addition of Er obviously improved the anti-wear properties, and reduced the friction coefficient of the alloys. The appropriate addition of Er would change the size and shape of the eutectic silicon, and thereby refine the microstructure of the Al-Si alloys. The refinement mechanism was also discussed. | 邢鹏飞 高波 庄艳歆 刘凯华 涂赣峰 | 2010 | Journal of Rare Earths2010，28，6： | 10 |
| 7 | High-resolution Remote Sensing Image Segmentation Using Minimum Spanning Tree Tessellation and RHMRF-FCM Algorithm显示文摘It is proposed a high resolution remote sensing image segmentation method which combines static minimum spanning tree(MST)tessellation considering shape information and the RHMRF-FCM algorithm.It solves the problems in the traditional pixel-based HMRF-FCM algorithm in which poor noise resistance and low precision segmentation in a complex boundary exist.By using the MST model and shape information,the object boundary and geometrical noise can be expressed and reduced respectively.Firstly,the static MST tessellation is employed for dividing the image domain into some sub-regions corresponding to the components of homogeneous regions needed to be segmented.Secondly,based on the tessellation results,the RHMRF model is built,and regulation terms considering the KL information and the information entropy are introduced into the FCM objective function.Finally,the partial differential method and Lagrange function are employed to calculate the parameters of the fuzzy objective function for obtaining the global optimal segmentation results.To verify the robustness and effectiveness of the proposed algorithm,the experiments are carried out with WorldView-3(WV-3)high resolution image.The results from proposed method with different parameters and comparing methods(multi-resolution method and watershed segmentation method in eCognition software)are analyzed qualitatively and quantitatively. | Wenjie LIN Yu LI Quanhua ZHAO | 2020 | Journal of Geodesy and Geoinformation Science2020，3，1： | 10 |
| 8 | Behaviour of layered sandstone under Brazilian test conditions:Layer orientation and shape effects显示文摘The experimental study in this paper focuses on the effects of the layer orientation and sample shape on failure strength and fracture pattern of samples tested under Brazilian test conditions(i.e.diametrical loading of cylindrical discs)for one particular layered sandstone which is from Modave in the south of Belgium.The variations of the strength in combination with the failure patterns are examined as a function of the inclination angle between the layer plane and the loading direction.The experimental,results clearly show that the induced fracture patterns are a combination of tensile and/or shear fractures.In shape effect experiments the layer thickness and the number of layer boundaries are investigated.Different blocks of Modave sandstone are used to prepare samples.The layer thickness is different among the various blocks,but the layer thickness in each studied rock block can be considered to be constant;hence,the number of layer boundaries changes according to the sample diameter for samples of the same block.The experimental study shows that the layer thickness plays a more important role than the number of layer boundaries per sample. | Abbass Tavallali André Vervoort | 2013 | Journal of Rock Mechanics and Geotechnical Engineering2013，5，5： | 9 |
| 9 | MapGIS向ArcGIS数据格式转换方法探讨显示文摘根据目前空间数据格式转换现状,探讨了MapGIS向ArcGIS数据格式转换的几种方法,对比分析了各种转换方法中点、线、面各类要素转换前后的差异,讨论利用软件本身的转换功能进行数据格式转换所存在的问题和解决方案。实践表明,通过Shape文件进行转换是实现MapGIS向ArcGIS数据格式转换的最佳途径,为获得理想的转换效果,有时需根据图形本身的特点和转换的要求选取一种或几种方法相结合,并在转换后进行适当的图形编辑工作。 | 黄云 | 2010 | 地矿测绘2010，26，1： | 9 |
| 10 | CONSTRAINED RATIONAL CUBIC SPLINE AND ITS APPLICATION显示文摘In this paper, a kind of rational cubic interpolation function with linear denominator is constructed. The constrained interpolation with constraint on shape of the interpolating curves and on the second-order derivative of the interpolating function is studied by using this interpolation, and as the consequent result, the convex interpolation conditions have been derived. | Qi Duan Huan-ling Zhang Xiang Lai Nan Xie Fu-hua(Frank)Cheng | 2001 | Journal of Computational Mathematics2001，19，2： | 9 |
| 11 | Shape optimization of 3D curved slots and its application to the squirrel-cage elastic support design显示文摘The squirrel-cage elastic support is one of the most important components of an aero-engine rotor system.A proper structural design will favor the static and dynamic performances of the system.In view of the deficiency of the current shape optimization techniques,a new mapping approach is proposed to define shape design variables based on the parametric equations of 3D curves and surfaces.It is then applied for the slot shape optimization of a squirrel-cage elastic support.To this end,an automatic design procedure that integrates the Genetic Algorithm (GA) is developed to solve the problem.Two typical examples with different shape constraints are considered.Numerical results provide reasonable optimum designs for the improvement of stiffness and strength of the squirrel-cage elastic support. | WANG Dan,ZHANG WeiHong*,WANG ZhenPei & ZHU JiHong Engineering Simulation and Aerospace Computing,The Key Laboratory of Contemporary Design & Integrated Manufacturing Technology,Northwestern Polytechnical University,Xi’an 710072,China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，10： | 8 |
| 12 | 基于geotools实现WebGIS应用软件显示文摘本文通过分析当前WebGIS开发中存在的问题,结构复杂,费用高,介绍采用免费公共库geotools和JavaJdbc开发互联网上GIS应用软件的方法,使得开发结构简单,费用降低.主要介绍通过Web服务器直接读取地理空间数据的解决方案和通过Jdbc读取属性数据的方法。 | 冯亦参 | 2006 | 微计算机信息2006，22，11S： | 8 |
| 13 | 1985-2015 年渤海海岸线和围填海的时空变迁研究(英文)显示文摘Extraction and analysis of the shoreline and land reclamation patterns are important for studies on topics such as the dynamics of coastal wetland ecological environments,transportation and exchange of material energy in coastal regions,and recruitment of fishery resources.Spatial-temporal variations in the shoreline and land reclamation in the Bohai Sea were analyzed based on 49 Landsat images of 7 periods from 1985 to 2015.The following conclusions were drawn.(1)The extracted shoreline data based on visual interpretation had high precision,and the shoreline extraction errors could be controlled within the theoretical range.(2)Over the past 30 years,the shoreline of the Bohai Sea has exhibited an average rate of change of 188.47 m/a and an average accretion distance of 3.55×10^3 m toward the sea.The fastest rate of shoreline change occurred in Laizhou Bay(134.78 m/a),followed by Bohai Bay(128.20 m/a)and Liaodong Bay(61.69 m/a).(3)The average rate of reclamation was 3.25×10^4 ha/a in the Bohai Sea,where the total area of aquaculture land,unused land,and salt land exceeded 60%of the total reclamation area.(4)The geometric shape of the bay became increasingly complicated from year to year,and the geometric center of gravity of the bay moved rapidly toward the sea.In addition,the area of the bay showed a significant decreasing trend.Therefore,to protect the function and structure of the ecosystem in coastal regions,we must control the scale and rate of land reclamation in the future. | 丁小松 单秀娟 陈云龙 金显仕 MUHAMMED Forruq Rahman | 2019 | Journal of Geographical Sciences2019，29，12： | 8 |
| 14 | ORDER STATE AND STABILITY OF MARTENSITE IN AN AIR-QUENCHED Cu-Zn-Al ALLOY显示文摘ORDERSTATEANDSTABILITYOFMARTENSITEINANAIR-QUENCHEDCu-Zn-AlALLOY￥WangMingpu;JinZhanpeng;YinZhimin;XuGenyin(DepartmentofMateria... | Wang Mingpu Jin Zhanpeng Yin Zhimin Xu Genyin(Department of Materials Science and Engineering,Central South University of Technology, Changsha 410083 Anhui Institute of Technology, Hefei 230069) | 1996 | 中国有色金属学会会刊:英文版1996，6，3： | 8 |
| 15 | Design optimization of cast Cu-Al-Be-B alloys for high damping capacity显示文摘This paper investigated high-damping Cu-Al-Be-B cast alloys using metallographic analysis, X-ray diffraction (XRD) and electrical resistance measurements for transformation temperatures. The results showed that beryllium can stabilize β phase, resulting in a thermo-elastic martensite microstructure leading to high-damping capacity in cast Cu-Al-Be-B alloys. Trace additions of boron to Cu-Al-Be alloys can significantly refine the grains, providing high strength and ductility to the alloys. A factorial design of experiment method was used to optimize the composition and properties of cast Cu-Al-Be-B alloys. The optimal microstructure for thermo-elastic martensite can be obtained by adjusting the amounts of aluminum and beryllium to eutectoid or pseudo-eutectoid compositions. An optimized cast Cu-Al-Be-B alloy was developed to provide excellent mechanical properties, tensile strength σ_b=767MPa, elongation δ=7.62%, and damping capacity S. D. C=18.70%. | ~*S. Lu~(1,2), W. H. Miao~1, J. Chen~1, P. H. Lin~2 (1. Department of Materials Engineering, East China Ship Building Institute of Technology, Zhenjiang 212003, Jiangsu, P. R. Chine 2. Department of Mechanical Engineering, Southeast University, Nonjing 210096, Jiangsu, P. R. Chine) | 2004 | China Foundry2004，1，S1： | 8 |
| 16 | Martensitic transformation involved mechanical behaviors and wide hysteresis of NiTiNb shape memory alloys | Minjuan Wang Mingyang Jiang Guangyue Liao Shun Guo Xinqing Zhao | 2012 | Progress in Natural Science:Materials International2012，22，2： | 7 |
| 17 | Recent progress in 4D printing of stimuli-responsive polymeric materials显示文摘4D printing is proposed based on the additive manufacturing of stimuli-responsive materials and structures,which can realize shape changing upon external stimuli.This article reviews the 4D printing methods and actuating performances of 4D printing structures based on shape memory polymers,hydrogels,liquid crystal elastomers,and electroactive polymers.This article shows that the shape morphing properties of single materials are limited,while 4D printing of composites can integrate the various driving modes of different smart materials.In the end,challenges facing 4D printing such as broadening the scope of smart materials,improving printing processes,the compatibility of printing different materials have been discussed. | MA SuQian ZHANG YunPeng WANG Meng LIANG YunHong REN Lei REN LuQuan | 2020 | Science China(Technological Sciences)2020，63，4： | 7 |
| 18 | Nonlinear hysteresis identification and compensation based on the discrete Preisach model of an aircraft morphing wing device manipulated by an SMA actuator显示文摘The conception of aircraft morphing wings thrives in aeronautics since the appearance of shape memory alloys(SMAs). An aircraft morphing wing device, manipulated by an SMA actuator, inherits the intrinsic nonlinear hysteresis from the SMA actuator, ending up with control disadvantages. Conventionally, systems with SMA actuators are constrained to bi-stable states to bypass the hysteresis region. Rather than retreating a morphing wing device to bi-stable states, this paper is dedicated to transcend the morphing wing device beyond the customary limit. A methodology of discrete Preisach modeling, which identifies the hysteresis of the morphing wing device, is proposed herein. An array of discrete equal-distance points is applied to the Preisach plane in order to derive the Preisach density over the partitioned unit of the Preisach plane. Discrete Preisach modeling is fulfilled by the discrete first-order reversible curve(DFORC). By utilizing the discrete Preisach model, the aircraft morphing wing device is simulated; the validity and accuracy of discrete Preisach modeling are demonstrated by contrasting the simulated outcome with experimental data of the major hysteretic loop and the wingspan-wise displacement over time; a comparison between simulation and experimental results exhibits consistency. Afterwards, a hysteresis compensation strategy put forward in this paper is implemented for quasi-linear control of the aircraft morphing wing device, which manifests a compensated shrinking hysteresis loop and attains the initiative of extending the morphing range to the intrinsic hysteretic region. | Yuchen CHEN Xing SHEN Jiefeng LI Jinjin CHEN | 2019 | Chinese Journal of Aeronautics2019，32，4： | 7 |
| 19 | Geometric morphometric analysis of the early Pleistocene hominin teeth from Jianshi,Hubei Province,China显示文摘Although the early Pleistocene hominin fossils found in East Asia continent are widely recognized as the earliest hominins migrated from Africa, debates remain on the morphology and taxonomy of these fossils. In this study, dental crown shape of the three early Pleistocene hominin teeth (P3, M1, and M1) found in Jianshi, Hubei Province of China was analyzed by means of geometric morphometrics. The comparative samples of fossil hominins from Africa, Asia, and Europe as well as those of modern humans (N=257) were used. The results indicate that the contour, asymmetry, and cusp patterns of these three types of teeth differ obviously between the fossil hominins and modern humans. The crown shape of P3 in most fossil hominins including Australopithecus, African early Homo, and Asian Pleistocene hominins are asymmetric with their crown occlusal contours long and curving elliptic-shaped. The occlusal contour of the fossil hominin M1 is symmetric and rectangle-shaped with no marked cusp protrusion. The crown shape of fossil M1 is characterized by asymmetric contour with slightly projected metaconid and hypoconid. On the contrary, in modern Chinese and some European late Pleistocene hominins, the crowns of P3s show symmetric contours with buccal side wider than lingual side; the crown shape of M1 is asymmetric with lingual cusp distalplaced, especially for hypoconid; the M1 has symmetric and round crown contour. Our study reveals that Australopithecus has wide variations in its crown shape, whereas these dental morphospaces of Asian hominins are closely placed. The crown contour, symmetry, and cusp patterns of these three teeth of Jianshi hominin resemble those of Asian early and middle Pleistocene hominins. No marked difference in dental crown shape is shown between the Jianshi hominin and other Chinese Homo erectus, and there is also no evidence in support of the Jianshi hominin's closeness to Australopithecus and African early Homo members. | Ronald CLARKE | 2010 | Science China Earth Sciences2010，53，8： | 7 |
| 20 | A Neural Network Recognition Method of Shape Pattern显示文摘A new pattern recognition method of shape was presented based onartificial neural network theory. The method avoids the defects of shape pattern recognition with polynomials and it has strong disturbance resistance. It has been proved to be superior in recognizing different shape patterns by identifying many sorts of working sample books which the results are known. | PENG Yan LIU Hong-min | 2001 | Journal of Iron and Steel Research(International)2001，8，1： | 7 |
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