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海底采矿车液压系统的特征数据多积分控制 被引量:2
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作者 乔桂玲 张文明 《机床与液压》 北大核心 2017年第10期95-99,共5页
在深海复杂环境下,海底采矿车液压控制系统采集到的数据含有高频噪声,由于常规PID控制中微分对高频噪声的放大作用,往往会降低系统的控制性能。为了消除高频噪声的影响,提出基于采矿车特征数据辨识的多积分控制器设计。该算法采用多积... 在深海复杂环境下,海底采矿车液压控制系统采集到的数据含有高频噪声,由于常规PID控制中微分对高频噪声的放大作用,往往会降低系统的控制性能。为了消除高频噪声的影响,提出基于采矿车特征数据辨识的多积分控制器设计。该算法采用多积分实现噪声滤波,同时,为了尽可能地提高系统的快速调节能力,先辨识出采矿车液压系统的特征数据,然后规划出系统的参考控制输出,最后利用特征数据和参考输出计算出控制器的参数。仿真结果验证了算法的可行性与有效性。 展开更多
关键词 海底采矿车 液压控制系统 特征数据 多积分控制器
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VSIA:一种求解流体力学方程的多积分矩公式(英文)
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作者 肖锋 《计算物理》 CSCD 北大核心 2003年第6期483-492,共10页
使用变量间的积分矩公式给出一种构造流体力学方程数值格式的方法 ,即体积面积分平均方法 (VSIA) .该方法使用两种积分矩VIA(体积积分平均 )和SIA(面积积分平均 )给出一种完全的守恒型体积积分公式 .基于一类守恒型半Lagrange输运算法CI... 使用变量间的积分矩公式给出一种构造流体力学方程数值格式的方法 ,即体积面积分平均方法 (VSIA) .该方法使用两种积分矩VIA(体积积分平均 )和SIA(面积积分平均 )给出一种完全的守恒型体积积分公式 .基于一类守恒型半Lagrange输运算法CIP CSL ,能够清晰地构造出VSIA .对一般演化方程进行讨论 ,并应用于Burgers湍流。 展开更多
关键词 流体力学方程 多积分矩公式 VSIA 体积积分平均 面积积分平均 Lagrange输运算法 Burgers湍流 无粘滞可压缩流 不可压缩粘滞流
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“固定相差分段”+“多积分”捕获方案
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作者 周常柱 《计算机与网络》 1999年第14期19-22,共2页
文章根据“固定相差分段捕获”和“顺序多积分捕获”原理,提出了一种直接序列扩频通信系统中新的PN序列捕获方案,并给出了实现框图及工作过程说明。
关键词 PN序列 固定相差 多积分
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顾及多积分时间特性的GF-4卫星PMS传感器交叉辐射定标 被引量:1
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作者 韩杰 陶醉 +2 位作者 谢勇 刘其悦 石宏斌 《测绘学报》 EI CSCD 北大核心 2020年第10期1311-1320,共10页
针对GF-4卫星PMS传感器具备5个积分时间的成像特性,提出一种基于辐射区域网平差的交叉辐射定标方法。首先,利用敦煌辐射校正场地区时间序列有效MODIS影像集,构建该区域高精度BRDF模型。其次,考虑BRDF和SBAF校正,从该地区Landsat-8卫星OL... 针对GF-4卫星PMS传感器具备5个积分时间的成像特性,提出一种基于辐射区域网平差的交叉辐射定标方法。首先,利用敦煌辐射校正场地区时间序列有效MODIS影像集,构建该区域高精度BRDF模型。其次,考虑BRDF和SBAF校正,从该地区Landsat-8卫星OLI影像和PMS影像中提取辐射控制点。然后,设置DN值和CV限制条件,在凝视成像状态下从不同积分时间PMS影像中提取辐射连接点。最后,利用新建定标模型计算各积分时间状态下的定标系数。验证结果表明,不同积分时间的各波段平均绝对定标精度均优于5.18%,且不同积分时间影像间各波段辐射差异最高降低36.64%。同时,探讨了辐射控制点分布、BRDF、SBAF和辐射连接点筛选条件对定标结果的影响,为进一步优化PMS传感器交叉辐射定标流程提供重要参考。 展开更多
关键词 GF-4 多积分时间 辐射区域网平差 BRDF SBAF
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The Calculation of Parameters for DNA Kinetic Structure Based on Monte-Carlo Multiple Integrals 被引量:1
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作者 崔向军 蔡禄 《Agricultural Science & Technology》 CAS 2010年第5期5-6,16,共3页
Based on protein-DNA complex crystal structural data in up-to-date Nucleic Acid Database,the related parameters of DNA Kinetic Structure were investigated by Monte-Carlo Multiple Integrals on the base of modified DNA ... Based on protein-DNA complex crystal structural data in up-to-date Nucleic Acid Database,the related parameters of DNA Kinetic Structure were investigated by Monte-Carlo Multiple Integrals on the base of modified DNA structure statistical mechanical model,and time complexity and precision were analyzed on the calculated results. 展开更多
关键词 Monte-Carlo method Multiple integrals DNA Time complexity Precision
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Weighted L^p-boundedness of Multilinear Oscillatory Singular Integrals with Calderón-Zygmund Kernel
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作者 田东风 燕敦验 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第1期33-40,共8页
In this paper, weighted L p-boundedness is obtained for a class of multilinear oscillatory singular integrals with Calderón-Zygmund kernel.
关键词 multilinear oscillatory integrals Calderón-Zygmund kernel A p-weight
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Subclasses of Meromorphic Multivalent Functions
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作者 徐能 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第1期65-70,共6页
In this paper we introduce some new subclesses of meromorphic multivalent functions. Inclusion relations between these classes, the class preserving integral operators and coefficient estimates are obtained.
关键词 MULTIVALENT mermorphic INTEGRAL COEFFICIENT
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High-Integrated-Photosensitivity Negative-Electron-Affinity GaAs Photocathodes with Multilayer Be-Doping Structures
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作者 王晓峰 曾一平 +4 位作者 王保强 朱占平 杜晓晴 李敏 常本康 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第9期1692-1698,共7页
The effect of changing Be doping concentration in GaAs layer on the integrated photosensitivity for nega- tive-electron-affinity GaAs photocathodes is investigated. Two GaAs samples with the monolayer structure and th... The effect of changing Be doping concentration in GaAs layer on the integrated photosensitivity for nega- tive-electron-affinity GaAs photocathodes is investigated. Two GaAs samples with the monolayer structure and the muhilayer structure are grown by molecular beam epitaxy. The former has a constant Be concentration of 1 × 10^19 cm^-3, while the latter includes four layers with Be doping concentrations of 1 × 10^19, 7 × 10^18, 4 × 10^18, and 1 × 10^18 cm^-3 from the bottom to the surface. Negative-electron-affinity GaAs photocathodes are fabricated by exciting the sample surfaces with alternating input of Cs and O in the high vacuum system. The spectral response results measured by the on-line spectral response measurement system show that the integrated photosensitivity of the photocathode with the muhilayer structure enhanced by at least 50% as compared to that of the monolayer structure. This attributes to the improvement in the crystal quality and the increase in the surface escape probability. Different stress situations are observed on GaAs samples with monolayer structure and muhilayer structure, respectively. 展开更多
关键词 integrated photosensitivity muhilayer structure NEA photocathode diffusion length surface escape probability
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Application of Eigenkets of Bosonic Creation Operator in Deriving Some New Formulas of Associated Laguerre Polynomials 被引量:1
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作者 FAN Hong-Yi WANG Tong-Tong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期315-320,共6页
Using the resolution of unity composed of bosonic creation operator's eigenkets and annihilation operator's un-normalized eigenket, which is a new quantum mechanical representation in contour integration form, we de... Using the resolution of unity composed of bosonic creation operator's eigenkets and annihilation operator's un-normalized eigenket, which is a new quantum mechanical representation in contour integration form, we derive new contour integration expression of associated Laguerre polynomials L^ρm (|z|^2) and its generalized generating function formula. A series of recursive relations regarding to L^ρm (|z|^2) are also deduced in the context of the Fock representation by algebraic method. 展开更多
关键词 bosonic creation operator Laguerre polynomials contour integration
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Exact Traveling Wave Solutions for a Kind of Generalized Ginzburg-Landau Equation 被引量:8
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作者 LIUCheng-Shi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期787-790,共4页
Using a complete discrimination system for polynomials, new exact traveling wave solutions for generalized Ginzburg-Landau equation are obtained. The method has general meaning for many similar problems.
关键词 generalized Ginzburg-Landau equation elementary integral method polynomialcomplete discrimination system
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A Multi-Domain Boundary Element Method to Analyze the Reflection and Transmission of Oblique Waves From Double Porous Thin Walls 被引量:5
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作者 Yamina Bakhti Nadji Chioukh +1 位作者 Benameur Hamoudi Mohamed Boukhari 《Journal of Marine Science and Application》 CSCD 2017年第3期276-285,共10页
In the present paper, we examine the performance of an efficient type of wave-absorbing porous marine structure under the attack of regular oblique waves by using a Multi-Domain Boundary Element Method(MDBEM). The str... In the present paper, we examine the performance of an efficient type of wave-absorbing porous marine structure under the attack of regular oblique waves by using a Multi-Domain Boundary Element Method(MDBEM). The structure consists of two perforated vertical thin barriers creating what can be called a wave absorbing chamber system. The barriers are surface piercing, thereby eliminating wave overtopping. The problem of the interaction of obliquely incident linear waves upon a pair of perforated barriers is first formulated in the context of linear diffraction theory. The resulting boundary integral equation, which is matched with far-field solutions presented in terms of analytical series with unknown coefficients, as well as the appropriate boundary conditions at the free surface, seabed, and barriers, is then solved numerically using MDBEM. Dissipation of the wave energy due to the presence of the perforated barriers is represented by a simple yet effective relation in terms of the porosity parameter appropriate for thin perforated walls. The results are presented in terms of reflection and transmission coefficients. The effects of the incident wave angles, relative water depths, porosities, depths of the walls, and other major parameters of interest are explored. 展开更多
关键词 oblique waves porous breakwater perforated thinwalls boundary element method REFLECTION transmission waveenergy dissipation
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Multi-component KN Hierarchy and Associated two Integrable Couplings as Well as Their Hamiltonian Structure 被引量:2
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作者 JIANG Xiao-wu LI Zhu 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期415-422,共8页
Firstly, a vector loop algebra G3 is constructed, by use of it multi-component KN hierarchy is obtained. Further, by taking advantage of the extending vector loop algebras G6 and G9 of G3 the double integrable couplin... Firstly, a vector loop algebra G3 is constructed, by use of it multi-component KN hierarchy is obtained. Further, by taking advantage of the extending vector loop algebras G6 and G9 of G3 the double integrable couplings of the multi-component KN hierarchy are worked out respectively. Finally, Hamiltonian structures of obtained system are given by quadratic-form identity. 展开更多
关键词 KN hierarchy integrable couplings quadratic-form identity Hamiltonian structure
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The Applicability of the Density Rule of Pathwardhan and Kumer and the Rule Based on Linear Isopiestic Relation 被引量:1
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作者 胡玉峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第3期319-321,共3页
The applicability of the density rule of Pathwardhan and Kumer and the rule based on the linear isopiestic relation is studied by comparison with experimental density data in the literature. Predicted and measured val... The applicability of the density rule of Pathwardhan and Kumer and the rule based on the linear isopiestic relation is studied by comparison with experimental density data in the literature. Predicted and measured values for 18 electrolyte mixtures are compared. The two rules are good for mixtures with and without common ions, including those containing associating ions. The deviations of the rule based on the linear isopiestic relation are slightly higher for the mixtures involving very strong ion complexes, but the predictions are still quite satisfactory.The density rule of Pathwardhan and Kumer is more accurate for these mixtures. However, it is not applicable for mixtures containing non-electrolytes. The rule based on the linear isopiestic relation is extended to mixtures involving non-electrolytes. The predictions for the mixtures containing both electrolytes and non-electrolytes and the non-electrolyte mixtures are accurate. All these results indicate that this rule is a widely applicable approach. 展开更多
关键词 binary density rules DENSITY apparent molar volume multicomponent system binary sub-system
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A new mutation (1062 del 16) of iduronate-2-sulfatase gene from a Chinese patient with Hunter syndrome 被引量:4
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作者 GUO Yi-bin PAN Jing-xin MENG Ya-xian 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第8期566-569,共4页
Objective: To identify the mutations of iduronate-2-sulfatase (IDS) gene, to reveal its mutation features, and to establish a basis for genetic counseling and prenatal gene diagnosis of Hunter syndrome. Methods: Urine... Objective: To identify the mutations of iduronate-2-sulfatase (IDS) gene, to reveal its mutation features, and to establish a basis for genetic counseling and prenatal gene diagnosis of Hunter syndrome. Methods: Urine glycosaminoglycans (GAGs) assay, PCR and DNA sequencing were performed to detect mutation of IDS gene of the patient and his parents. Results: The result showed that the patient was: DS(++), HS(++), KS(-), CS(-), and that both of his parents were negative. A frame-shift deletion mutation (1062 del 16) was identified in exon 7 of the patient's IDS gene. His parents' genotypes were normal. Conclusion:The patient's mutation was not inherited by his parents but a novel one. The mutation probably altered the primary structure and tertiary structure of IDS enzyme protein remarkably and lowered the activity of IDS enzyme greatly. Therefore it is supposed to be the direct cause of the disorder. 展开更多
关键词 Hunter syndrome Mucopolysaccharidosis typeⅡ (MPSⅡ) Glycosaminoglycan (GAG) Iduronate-2-sulfatase (IDS) Mutation Gene diagnosis DNA sequencing
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On Meromorphic Starlike Multivalent Functions 被引量:1
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作者 杨定恭 《Chinese Quarterly Journal of Mathematics》 CSCD 1993年第3期88-93,共6页
In this paper we introduce and study some new subclasses of meromorphic starlike multivalent functions.Inclusion relations are established,Integral transforms of functions in these classes are also considered.In parti... In this paper we introduce and study some new subclasses of meromorphic starlike multivalent functions.Inclusion relations are established,Integral transforms of functions in these classes are also considered.In particular,our results include or improve several results due to Mogra et al.[2],Mogra [3],Goel and Sohe[4]and Bajpai[5]. 展开更多
关键词 meromorphic function starlike function multivalent function integral transform.
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A New Loop Algebra and Its Corresponding Multi-component Integrable Hierarchy
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作者 YAO Yu-Qin CHEN Deng-Yuan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期385-388,共4页
A type of new loop algebra GM is constructed by making use of the concept of cycled numbers. As its application, an isospectral problem is designed and a new multi-component integrable hierarchy with multi-potential f... A type of new loop algebra GM is constructed by making use of the concept of cycled numbers. As its application, an isospectral problem is designed and a new multi-component integrable hierarchy with multi-potential functions is worked out, which can be reduced to the famous KN hierarchy. 展开更多
关键词 cycled numbers loop algebra multi-component integrable hierarchy
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Multi-component Levi Hierarchy and Its Multi-component Integrable Coupling System
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作者 XIA Tie-Cheng YOU Fu-Cai ZHAO Wen-Ying 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期990-996,共7页
A simple 3M-dimensional loop algebra X is produced, whose commutation operation defined by us is A1 as simple and straightforward as that in the loop algebra A1. It follows that a general scheme for generating multi-... A simple 3M-dimensional loop algebra X is produced, whose commutation operation defined by us is A1 as simple and straightforward as that in the loop algebra A1. It follows that a general scheme for generating multi-component integrable hierarchy is proposed. By taking advantage of X, a new isospectral problem is established, and then by making use of the Tu scheme the well-known multi-component Levi hierarchy is obtained. Finally, an expanding loop algebra FM of the loop algebra .X is presented, based on the FM, the multi-component integrable coupling system of the multi-component Levi hierarchy is worked out. The method in this paper can be applied to other nonlinear evolution equation hierarchies. 展开更多
关键词 loop algebra multi-component Levi hierarchy multi-component integrable coupling system
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Integrable Coupling of (2+1)-Dimensional Multi-component DLW Integrable Hierarchy and Its Hamiltonian Structure
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作者 YANG Geng-Wen ZHANG Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第1期45-49,共5页
A new multi-component Lie algebra is constructed, and a type of new loop algebra is presented. A (2+1)-dimensional multi-component DLW integrable hierarchy is obtained by using a (2+1)-dimensional zero curvature... A new multi-component Lie algebra is constructed, and a type of new loop algebra is presented. A (2+1)-dimensional multi-component DLW integrable hierarchy is obtained by using a (2+1)-dimensional zero curvature equation. Furthermore, the loop algebra is expanded into a larger one and a type of integrable coupling system and its corresponding Hamiltonian structure are worked out. 展开更多
关键词 (2+1)-dimensional multi-component integrable hierarchy Hamiltonian structure
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Strong/weak limits and strong/weak differentials of multi-variable indeterminate forms. II: Supplementary annotations and analysis
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作者 SONGGuangshi 《Journal of Chongqing University》 CAS 2004年第1期108-112,共5页
Supplementary annotations on special forms 1to 4, discussion on the general characteristics of K(t) and K(t, t), and analyses on two noticeable limits are presented in this part. It is demonstrated that strong and wea... Supplementary annotations on special forms 1to 4, discussion on the general characteristics of K(t) and K(t, t), and analyses on two noticeable limits are presented in this part. It is demonstrated that strong and weak parabolic transforms can be employed to change the standard form of a multi-variable indeterminate form into xmK type, hence to derive the standard formulae of the limit and the differential. 展开更多
关键词 parabolic transform indeterminate form multi-variable special form
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occurrence and microscopic analyses of multicellular magnetotactic prokaryotes from coastal sediments in the Yellow Sea 被引量:5
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作者 周克 潘红苗 +3 位作者 张圣妲 岳海东 肖天 吴龙飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第2期246-251,共6页
Multicellular magnetotactic prokaryotes (MMPs) are a group of aggregates composed of 7-45 gram-negative cells synthesizing intracellular magnetic crystals. Although they are thought to be globally distributed, MMPs ... Multicellular magnetotactic prokaryotes (MMPs) are a group of aggregates composed of 7-45 gram-negative cells synthesizing intracellular magnetic crystals. Although they are thought to be globally distributed, MMPs have been observed only in marine environments in America and Europe. Most MMPs share a rosette-like morphology and biomineralize iron sulfide crystals. In the present study, abundant MMPs were observed, with a density of 26 ind./cm^3, in the sediments of a coastal lagoon, Lake Yuehu, in the Yellow Sea. Optical microscopy showed that all of them were rosette shaped with a diameter of 5.5±0.8 μm. Transmission electron microscopy revealed that these MMPs were composed of 10- 16 ovoid cells and flagellated peritrichously. High-resolution transmission electron microscopy and energy dispersive X-ray analysis indicated that they biomineralized bullet-shaped magnetite crystals in highly organized parallel chains within which the magnetosomes were oriented in the same direction. This is the first report of MMPs from Asia and demonstrates the ubiquitous distribution of MMPs. 展开更多
关键词 multicellular magnetotactic prokaryotes rosette-like MAGNETOSOMES MAGNETITE Yellow Sea
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