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Linear magnetoresistance and structural distortion in layered SrCu_(4-x)P_(2) single crystals
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作者 聂勇 陈正 +10 位作者 韦文森 李慧杰 张勇 梅明 王园园 宋文海 宋东升 王钊胜 朱相德 宁伟 田明亮 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期591-594,共4页
We report a systematic study on layered metal SrCu_(4-x)P_(2) single crystals via transport, magnetization, thermodynamic measurements and structural characterization. We find that the crystals show large linear magne... We report a systematic study on layered metal SrCu_(4-x)P_(2) single crystals via transport, magnetization, thermodynamic measurements and structural characterization. We find that the crystals show large linear magnetoresistance without any sign of saturation with a magnetic field up to 30T. We also observe a phase transition with significant anomalies in resistivity and heat capacity at T_(p)~140 K. Thermal expansion measurement reveals a subtle lattice parameter variation near Tp, i.e.,?L_(c)/L_(c)~0.062%. The structural characterization confines that there is no structure transition below and above T_(p). All these results suggest that the nonmagnetic transition of SrCu_(4-x)P_(2) could be associated with structural distortion. 展开更多
关键词 linear magnetoresistance thermal expansion specific heat structural distortion
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Bulging Distortion of Austenitic Stainless Steel Sheet on the Partially Penetrated Side of Non-Penetration Lap Laser Welding Joint
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作者 Chengwu Yao Enze Liu +1 位作者 Jiaming Ni Binying Nie 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期286-295,共10页
Non-penetration laser welding of lap joints in austenitic stainless steel sheets is commonly preferred in fields where the surface quality is of utmost importance.However,the application of non-penetration welded aust... Non-penetration laser welding of lap joints in austenitic stainless steel sheets is commonly preferred in fields where the surface quality is of utmost importance.However,the application of non-penetration welded austenitic stainless steel parts is limited owing to the micro bulging distortion that occurs on the back surface of the partial penetration side.In this paper,non-penetration lap laser welding experiments,were conducted on galvanized and SUS304 austenitic stainless steel plates using a fiber laser,to investigate the mechanism of bulging distortion.A comparative experiment of DC01 galvanized steel-Q235 carbon steel lap laser welding was carried out,and the deflection and distortion profile of partially penetrated side of the sheets were measured using a noncontact laser interferometer.In addition,the cold-rolled SUS304 was subjected to heat holding at different temperatures and water quenching after bending to characterize its microstructure under tensile and compressive stress.The results show that,during the heating stage of the thermal cycle of laser lap welding,the partial penetration side of the SUS304 steel sheet generates compressive stress,which extrudes the material in the heat-affected zone to the outside of the back of the SUS304 steel sheet,thereby forming a bulge.The findings of these experiments can be of great value for controlling the distortion of the partial penetrated side of austenitic stainless steel sheet during laser non-penetration lap welding. 展开更多
关键词 Non-penetration lap laser welding Bulging distortion Austenitic stainless steel Compressive stress Tension stress
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Computational Quantification of Map Projection Distortion by Fractal Dimension of Coastlines
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作者 Franklin Lee 《Journal of Applied Mathematics and Physics》 2024年第5期1890-1903,共14页
Maps, essential tools for portraying the Earth’s surface, inherently introduce distortions to geographical features. While various quantification methods exist for assessing these distortions, they often fall short w... Maps, essential tools for portraying the Earth’s surface, inherently introduce distortions to geographical features. While various quantification methods exist for assessing these distortions, they often fall short when evaluating actual geographic features. In our study, we took a novel approach by analyzing map projection distortion from a geometric perspective. We computed the fractal dimensions of different stretches of coastline before and after projection using the divide-and-conquer algorithm and image processing. Our findings revealed that map projections, even when preserving basic shapes, inevitably stretch and compress coastlines in diverse directions. This analysis method provides a more realistic and practical way to measure map-induced distortions, with significant implications for cartography, geographic information systems (GIS), and geomorphology. By bridging the gap between theoretical analysis and real-world features, this method greatly enhances accuracy and practicality when evaluating map projections. 展开更多
关键词 Map Projection distortion COASTLINE Fractal Dimension CARTOGRAPHY Geographic Information Systems
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DISTORTION THEOREMS FOR CLASSES OF g-PARAMETRIC STARLIKE MAPPINGS OF REAL ORDER IN C^(n)
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作者 刘红炎 涂振汉 熊良鹏 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1491-1502,共12页
In this paper,we define the class S_(g)^(BX)of g-parametric starlike mappings of real order γ on the unit ball BX in a complex Banach space X,where g is analytic and satisfies certain conditions.By establishing the d... In this paper,we define the class S_(g)^(BX)of g-parametric starlike mappings of real order γ on the unit ball BX in a complex Banach space X,where g is analytic and satisfies certain conditions.By establishing the distortion theorem of the Fr´echet-derivative type of S_(g)^(BX)with a weak restrictive condition,we further obtain the distortion results of the Jacobi-determinant type and the Fr´echet-derivative type for the corresponding classes(compared with S_(g)^(BX))defined on the unit polydisc(resp.unit ball with the arbitrary norm)in the space of n-dimensional complex variables,n≥2.Our results extend the classic distortion theorem of holomorphic functions from the case in one-dimensional complex space to the case in the higher dimensional complex space.The main theorems also generalize and improve some recent works. 展开更多
关键词 Banach space distortion theorem of Jacobi-determinant type distortion theorems of the Frechet-derivative type g-parametric starlike mappings
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Correction of distorted X-ray absorption spectra collected with capillary sample cell
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作者 Hao Wang Yue-Cheng Lai +7 位作者 Jia-Jun Zhong Yun-Peng Liu Lei Yao Li-Xiong Qian Xue-Qing Xing Zhong-Jun Chen Guang Mo Zhong-Hua Wu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第7期179-188,共10页
In certain exceptional cases,capillary samples must be used to measure X-ray absorption spectra(XAS).However,the inho-mogeneous thickness of capillary samples causes XAS distortion.This study discusses the distortion ... In certain exceptional cases,capillary samples must be used to measure X-ray absorption spectra(XAS).However,the inho-mogeneous thickness of capillary samples causes XAS distortion.This study discusses the distortion and correction of the XAS curve caused by the inhomogeneous thickness of capillary samples.The relationship between the distorted XAS curveμ′d_(eq)(measured values)and the real absorption coefficientμ_(s)d_(eq)(true values)of the sample was established.The distortion was slight and negligible when the vertical size(2h)of the X-ray beam spot was smaller than 60%of the capillary tube’s inner diameter(2R_(in)).When h/R_(in)>1,X-ray leakage is inevitable and should be avoided during measurement.Partial X-ray leakage caused by an X-ray beam spot size larger than the inner diameter of the capillary tube leads to serious compressed distortion of the XAS curve.When h/R_(in)<1,the distorted XAS data were well corrected.Possible errors and their influence on the corrected XAS are also discussed.Simulations and corrections for distortions verify the feasibility and effectiveness of the corrected method. 展开更多
关键词 XAS CAPILLARY Compression distortion CORRECTION PYTHON
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Out-of-plane weak ferromagnetism at room temperature in lattice-distortion non-collinear antiferromagnet of single-crystal Mn_(3)Sn
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作者 张博熙 宋平 +2 位作者 邓珊珊 娄理 姚森 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期428-432,共5页
Out-of-plane weak ferromagnetic(OWFM)spin arrangements with topological properties can realize a series of interesting physical properties.However,this spin structure tends to exist at low temperatures.The OWFM struct... Out-of-plane weak ferromagnetic(OWFM)spin arrangements with topological properties can realize a series of interesting physical properties.However,this spin structure tends to exist at low temperatures.The OWFM structure can also be induced at room temperature by hydrostatic pressure,whereas this isotropic approach tends to form helical AFM structures.We report the OWFM spin arrangement in single crystal Mn_(3)Sn by an anisotropic strategy of high-stressconstrained compression deformation at room temperature.Both experimental and theoretical simulation results show that the alignment of the OWFM spin structure is due to the distortion of the atomic scale caused by the strain energy during deformation.The OWFM spin arrangement can significantly change the magnetic property of Mn_(3)Sn.As a result,the remanent magnetization M_(r)for the deformed sample(0.056μ_(B)/f.u.)is about eleven times that for the pre-deformed sample(0.005μ_(B)/f.u.),and the coercivity(H_(c))increases from 0 k Oe(pre-deformed sample)to 6.02 k Oe(deformed sample).Our findings provide a way to generate the OWFM spin structure at room temperature and may give fresh ideas for creating antiferromagnetic materials with excellent physical properties. 展开更多
关键词 non-collinear antiferromagnet high-stress-constrained compression deformation lattice distortion
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Distortion Evaluation of EMP Sensors Using Associated-Hermite Functions
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作者 Rupo Ma Siping Gao 《Computers, Materials & Continua》 SCIE EI 2023年第1期1093-1105,共13页
Electromagnetic pulse(EMP)is a kind of transient electromagnetic phenomenon with short rise time of the leading edge and wide spectrum,which usually disrupts communications and damages electronic equipment and system.... Electromagnetic pulse(EMP)is a kind of transient electromagnetic phenomenon with short rise time of the leading edge and wide spectrum,which usually disrupts communications and damages electronic equipment and system.It is challenging for an EMP sensor to measure a wideband electromagnetic pulse without distortion for the whole spectrum.Therefore,analyzing the distortion of EMP measurement is crucial to evaluating the sensor distortion characteristics and correcting the measurement results.Waveform fidelity is usually employed to evaluate the distortion of an antenna.However,this metric depends on specific signal waveforms,thus is unsuitable for evaluating and analyzing the distortion of EMP sensors.In this paper,an associated-hermite-function based distortion analysis method including system transfer matrices and distortion rates is proposed,which is general and independent from individual waveforms.The system transfer matrix and distortion rate can be straightforwardly calculated by the signal orthogonal transformation coefficients using associated-hermite functions.Distortion of a sensor vs.frequency is then visualized via the system transfer matrix,which is convenient in quantitative analysis of the distortion.Measurement of a current probe,a coaxial pulse voltage probe and a B-field sensor were performed,based on which the feasibility and effectiveness of the proposed distortion analysis method is successfully verified. 展开更多
关键词 Electromagnetic pulse associated-hermite functions system transfer matrix distortion rate
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Distortion product otoacoustic emissions in newborn babies with and without late-term maternal iron deficiency anaemia
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作者 Deepashree Somanahalli Ramachandra Ajith Kumar Uppunda Kumar Gavali Suryanarayana 《Journal of Otology》 CAS CSCD 2023年第3期132-138,共7页
Background:Studies on animals have demonstrated that maternal iron deficiency anaemia(IDA)could result in decreased cochlear sensory hair cells and reduced amplitudes of distortion-product otoacoustic emissions(DPOAEs... Background:Studies on animals have demonstrated that maternal iron deficiency anaemia(IDA)could result in decreased cochlear sensory hair cells and reduced amplitudes of distortion-product otoacoustic emissions(DPOAEs)of young guinea pigs.Thus,it is essential to study the functioning of cochlear hair cells using DPOAEs in human newborn babies with maternal IDA.The current study explores maternal IDA’s effect on DPOAEs in newborn babies.Method:A total of 110 newborn babies with gestational age≥34 weeks were considered and a‘betweensubjects’design was used.The participants were divided into 3 groups-“Normal”(61 babies without maternal IDA),“Mild”(28 babies with mild maternal IDA)and“Moderate”(21 babies with moderate maternal IDA).The cord blood was collected and the DPOAEs were recorded for each baby for a range of frequencies(1 k 8 kHz)and a range of intensities(7040 dB SPL in 10 dB steps).Results:The analysis of both DP-gram and DP input-output(I/O)function showed that there was no significant difference(p>0.05)across the normal,mild,and moderate groups in the overall presence of DPOAEs as well as the amplitude across frequencies or intensities(7040 dB SPL).Also,the overall correlation of RBC indices with DPOAE amplitude across frequencies as well as the slope of the I/O function showed no relationship.Conclusion:The current study concludes that there is no effect of late-term maternal IDA on the DPOAEs of newborn babies. 展开更多
关键词 Maternal iron deficiency anaemia Newborn babies distortion product otoacoustic emissions Cochlear hair cell functioning Red blood cell indices HAEMOGLOBIN
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水稻内稃扭曲突变体palea distortion 1(pd1)的鉴定与基因定位 被引量:1
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作者 郭爽 李云峰 +3 位作者 任德勇 王增 杜青 何光华 《分子植物育种》 CAS CSCD 2011年第3期256-260,共5页
在对籼稻缙恢10进行EMS(ethyl methane sulfonate)处理后的群体中,发现一个花器官突变体,主要表现为内稃扭曲并呈现外稃化特征,浆片数目增加且呈现稃状特征,雄蕊数目减少至1~4个,部分雄蕊的花丝呈现浆片化特征,暂将其命名为水稻颖壳扭... 在对籼稻缙恢10进行EMS(ethyl methane sulfonate)处理后的群体中,发现一个花器官突变体,主要表现为内稃扭曲并呈现外稃化特征,浆片数目增加且呈现稃状特征,雄蕊数目减少至1~4个,部分雄蕊的花丝呈现浆片化特征,暂将其命名为水稻颖壳扭曲突变体palea distortion 1(pd1)。遗传分析表明该突变性状受一个隐形单基因控制。利用群体分离分析法(bulked segregation analysis,BSA),将PD1基因定位在第2染色体的RM13693和RM13936之间,遗传距离分别为3.25cM和3.90cM。该研究结果为PD1基因的图位克隆奠定了基础。 展开更多
关键词 水稻 palea distortION 1(pd1) 突变体 基因定位
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Low stress no distortion welding for aerospace shell structures 被引量:3
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作者 GUAN Qiao GUO Delun and ZHANG Chongxian(Beijing Aeronautical Manufacturing Technology Research Institue. P.O Box 304. Beijing.100024) 《China Welding》 EI CAS 1996年第1期1-9,共9页
To fit in with the strict geometrical integrity and ensure dimensionally consistent fabrication of the welded aerospace structures. the low stress no distortion(LSND)welding, a technique for thin materials, was poinee... To fit in with the strict geometrical integrity and ensure dimensionally consistent fabrication of the welded aerospace structures. the low stress no distortion(LSND)welding, a technique for thin materials, was poineered and developed to provide an ininprocess active control of welding distortion. Satisfactory distortion free results were achieved in both welding of jet engine cases of heat-resistance alloys and rocket fuel tanks of aluminuim alloys, and there need no. reworking operations for post-weld distortion correction. Based on the 'static' method a newly developed method for dvnamic in-process control is also discussed in this paper. Both methods provide quanutiative in-process control of incompatible strains in weld zone and low stress no distortion welding results. 展开更多
关键词 aerospace shell structure residual stress distortION low stress no distortion Welding
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Binary Image Steganalysis Based on Distortion Level Co-Occurrence Matrix 被引量:2
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作者 Junjia Chen Wei Lu +4 位作者 Yuileong Yeung Yingjie Xue Xianjin Liu Cong Lin Yue Zhang 《Computers, Materials & Continua》 SCIE EI 2018年第5期201-211,共11页
In recent years,binary image steganography has developed so rapidly that the research of binary image steganalysis becomes more important for information security.In most state-of-the-art binary image steganographic s... In recent years,binary image steganography has developed so rapidly that the research of binary image steganalysis becomes more important for information security.In most state-of-the-art binary image steganographic schemes,they always find out the flippable pixels to minimize the embedding distortions.For this reason,the stego images generated by the previous schemes maintain visual quality and it is hard for steganalyzer to capture the embedding trace in spacial domain.However,the distortion maps can be calculated for cover and stego images and the difference between them is significant.In this paper,a novel binary image steganalytic scheme is proposed,which is based on distortion level co-occurrence matrix.The proposed scheme first generates the corresponding distortion maps for cover and stego images.Then the co-occurrence matrix is constructed on the distortion level maps to represent the features of cover and stego images.Finally,support vector machine,based on the gaussian kernel,is used to classify the features.Compared with the prior steganalytic methods,experimental results demonstrate that the proposed scheme can effectively detect stego images. 展开更多
关键词 Binary image steganalysis informational security embedding distortion distortion level map co-occurrence matrix support vector machine.
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Fish-Eye Image Distortion Correction Based on Adaptive Partition Fitting 被引量:2
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作者 Yibin He Wenhao Xiong +3 位作者 Hanxin Chen Yuchen Chen Qiaosen Dai Panpan Tuand Gaorui Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第1期379-396,共18页
The acquisition of images with a fish-eye lens can cause serious image distortion because of the short focal length of the lens.As a result,it is difficult to use the obtained image information.To make use of the effe... The acquisition of images with a fish-eye lens can cause serious image distortion because of the short focal length of the lens.As a result,it is difficult to use the obtained image information.To make use of the effective information in the image,these distorted imagesmust first be corrected into the perspective of projection images in accordance with the human eye’s observation abilities.To solve this problem,this study presents an adaptive classification fitting method for fish-eye image correction.The degree of distortion in the image is represented by the difference value of the distances fromthe distorted point and undistorted point to the center of the image.The target points selected in the image are classified by the difference value.In the areas classified by different distortion differences,different parameter curves were used for fitting and correction.The algorithm was verified through experiments.The results showed that this method has a substantial correction effect on fish-eye images taken by different fish-eye lenses. 展开更多
关键词 Fish-eye lens image distortion distortion difference adaptive partition fitting
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Rate-distortion optimized frame dropping and scheduling for multi-user conversational and streaming video 被引量:1
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作者 CHAKARESKI Jacob STEINBACH Eckehard 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第5期864-872,共9页
We propose a Rate-Distortion (RD) optimized strategy for frame-dropping and scheduling of multi-user conversa- tional and streaming videos. We consider a scenario where conversational and streaming videos share the fo... We propose a Rate-Distortion (RD) optimized strategy for frame-dropping and scheduling of multi-user conversa- tional and streaming videos. We consider a scenario where conversational and streaming videos share the forwarding resources at a network node. Two buffers are setup on the node to temporarily store the packets for these two types of video applications. For streaming video, a big buffer is used as the associated delay constraint of the application is moderate and a very small buffer is used for conversational video to ensure that the forwarding delay of every packet is limited. A scheduler is located behind these two buffers that dynamically assigns transmission slots on the outgoing link to the two buffers. Rate-distortion side information is used to perform RD-optimized frame dropping in case of node overload. Sharing the data rate on the outgoing link between the con- versational and the streaming videos is done either based on the fullness of the two associated buffers or on the mean incoming rates of the respective videos. Simulation results showed that our proposed RD-optimized frame dropping and scheduling ap- proach provides significant improvements in performance over the popular priority-based random dropping (PRD) technique. 展开更多
关键词 RATE-distortION optimization VIDEO FRAME dropping CONVERSATIONAL video Streaming video distortion matrix Hinttracks Scheduling Resource assignment
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Effects of distance between arc and heat sink on stress and distortion in DC-LSND welding technology 被引量:1
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作者 李菊 关桥 +3 位作者 郭德伦 杜欲晓 孙永春 史耀武 《China Welding》 EI CAS 2007年第3期6-9,共4页
The characteristics of temperatures, stresses and strains fields have been studied numerically for a titanium alloy sheet welded with an improved gas tungsten arc welding method, in which a trailing spot heat sink is ... The characteristics of temperatures, stresses and strains fields have been studied numerically for a titanium alloy sheet welded with an improved gas tungsten arc welding method, in which a trailing spot heat sink is introduced to control the welding stress and distortion. The impinging jet model is employed to describe the internee heat transfer between the cooling media and the top suufuce of the workpiece. The influcnee of the distance between arc and heat sink is investigated. Results show that there is an ideal range of distance. Using the ideal distance, a low stress and no distortion welding structure can be derived. 展开更多
关键词 gas tungsten arc welding dynamically controlled low stress no distortion STRESS distortION finite element method titanium alloy
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SHARP DISTORTION THEOREMS FOR A CLASS OF BIHOLOMORPHIC MAPPINGS IN SEVERAL COMPLEX VARIABLES 被引量:1
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作者 刘小松 《Acta Mathematica Scientia》 SCIE CSCD 2022年第2期454-466,共13页
In this paper,we first establish the sharp growth theorem and the distortion theorem of the Frechet derivative for biholomorphic mappings defined on the unit ball of complex Banach spaces and the unit polydisk in C^(n... In this paper,we first establish the sharp growth theorem and the distortion theorem of the Frechet derivative for biholomorphic mappings defined on the unit ball of complex Banach spaces and the unit polydisk in C^(n) with some restricted conditions.We next give the distortion theorem of the Jacobi determinant for biholomorphic mappings defined on the unit ball of C^(n) with an arbitrary norm and the unit polydisk in C^(n) under certain restricted assumptions.Finally we obtain the sharp Goluzin type distortion theorem for biholomorphic mappings defined on the unit ball of complex Banach spaces and the unit polydisk in C^(n) with some additional conditions.The results derived all reduce to the corresponding classical results in one complex variable,and include some known results from the prior literature. 展开更多
关键词 Biholomorphic mapping distortion theorem Frechet derivative Jacobi determinant Goluzin type distortion theorem
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WTO体制中的“扭曲”(DISTORTION)概念解析
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作者 盛杰民 云昌智 《经济法论坛》 2003年第1期181-201,共21页
在国际贸易法最近十几年的发展中,尤其是在 WTO 成立以来,国际贸易法总体上经历了一个朝着全球一体化方向迅速发展的过程。而就国际贸易法的传统部门法——国际反补贴规则体系而言,一个居于核心地位的概念始终吸引着我们的理论兴趣,这就... 在国际贸易法最近十几年的发展中,尤其是在 WTO 成立以来,国际贸易法总体上经历了一个朝着全球一体化方向迅速发展的过程。而就国际贸易法的传统部门法——国际反补贴规则体系而言,一个居于核心地位的概念始终吸引着我们的理论兴趣,这就是"扭曲"(DISTORTION)概念。虽然在"乌拉圭回合补贴与反补贴措施协定"中回避了在立法中直接加入"扭曲"概念的做法,而是采取以"负面影响"(ADVERSE EFFECTS) 展开更多
关键词 国际贸易法 概念解析 WTO体制 distortION 乌拉圭回合 规则体系 部门法 反补贴法 理论兴趣 复杂型
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ON THE STABILITY OF DISTORTED LAMINAR FLOW(Ⅱ)——THE LINEAR STABILITY ANALYSIS OF DISTORTED PARALLEL SHEAR FLOW
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作者 周哲玮 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第3期243-250,共8页
Based on the hydrodynamic stability theory of distorted laminar flow and the kind of distortion profiles on the mean velocity in parallel shear flow given in paper [1], this paper investigates the linear stability beh... Based on the hydrodynamic stability theory of distorted laminar flow and the kind of distortion profiles on the mean velocity in parallel shear flow given in paper [1], this paper investigates the linear stability behaviour of parallel shear flow, presents unstable results of plane Couette flow and pipe Poiseuille flow to two-dimensional or axisymmetric disturbances for the first time, and obtains neutral curves of these two motions under certain definition. 展开更多
关键词 FIGURE MODE THE LINEAR STABILITY ANALYSIS OF distortED PARALLEL SHEAR FLOW ON THE STABILITY OF distortED LAMINAR FLOW
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ON THE STABILITY OF DISTORTED LAMINAR FLOW(Ⅲ)—THE NONLINEAR STABILITY ANALYSIS OF DISTORTED PARALLEL SHEAR FLOW
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作者 周哲玮 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第4期297-307,共11页
Based on the hydrodynamic stability theory of distorted laminar flow and the kind of distortion profiles on the mean velocity in parallel shear flow given in paper [1], this paper investigates the nonlinear stability ... Based on the hydrodynamic stability theory of distorted laminar flow and the kind of distortion profiles on the mean velocity in parallel shear flow given in paper [1], this paper investigates the nonlinear stability behaviour of parallel shear flow, carries on stability calculation taking account of the perturbations of background turbulence noise under certain assumption, and obtains some results in accordance qualitatively with those of experiment for plane Poiseuille flow and pipe Poiseuille flow. 展开更多
关键词 ON THE STABILITY OF distortED LAMINAR FLOW THE NONLINEAR STABILITY ANALYSIS OF distortED PARALLEL SHEAR FLOW
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The Trends and Tasks of Modeling and Simulation for Reduction of Heat Treatment Distortion 被引量:7
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作者 Kiyoshi Funatani Nihon Parkerizing Co., Ltd.Momosono-cho 4-18, Mizuho-ku, Nagoya, JAPAN 《Journal of Shanghai Jiaotong university(Science)》 EI 2000年第1期35-41,共7页
The development of simulation model and benchmark work have expanded in the past decade and many models and soft ware are introduced. The leading software "Hearts’ developed by Prof Inoue[1] and several other ha... The development of simulation model and benchmark work have expanded in the past decade and many models and soft ware are introduced. The leading software "Hearts’ developed by Prof Inoue[1] and several other have proved the effectiveness as the pre-production simulation work at many part of heat treatment processes[2-10]. Although, numerous other models and simulation studies dealt with many fundamental factors are reported at many conferences except very few models have not completed three dimensional computation methods, or lack of validation work to evaluate their tools exactly. In this paper, several distortion case studies will be introduced and the needs of fundamental study of distortion and internationally collaborative program on model evaluation and construction of materials database are proposed. 展开更多
关键词 Simulation model HEAT treatment Materials data base COOLING power distortION
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Prediction of welding distortion during assembly process of thin plate structures 被引量:12
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作者 罗宇 邓德安 江晓玲 《China Welding》 EI CAS 2005年第2期153-157,共5页
Ships and automobiles are fabricated front thin plates. To assemble parts, welding is commonly employed. However, welding distortion in large thin-plate panel structure is usually cased by buckling due to the residual... Ships and automobiles are fabricated front thin plates. To assemble parts, welding is commonly employed. However, welding distortion in large thin-plate panel structure is usually cased by buckling due to the residual stress. In this study, an elastic finite element method for predicting the welding distortion of three-dimensional thin-plate structures with considering welding sequence was proposed. In this method, the inherent strain was employed to model the local shrinkage due to welding itself, and the interface element was introduced to simulate the assembly process. The proposed method was applied to study the influence of welding sequence on the buckling distortion of the large thin-plate panel structure during assembly. 展开更多
关键词 welding distortion BUCKLING finite element method interface element welding sequence
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