查询词典 approximation methods in physics

We used different methods to calculate luminosity in order to assure its reliability. Structure function method is adopted to derive the radiatively corrected cross section whose accuracy is up to 1%. The corrections from vacuum polarization and effect of energy spread are also studied. The final analytical approximation formulaes of the observed cross sections are worked out. Different fitting methods are carried out to fit the resonances according to different requests.

模拟的分布图的仔细对比，并兼顾实验的要求，得到每种事例对应的选择条件，特别是在处理积分亮度时，更是采用了不同的方法，以保证亮度计算的可靠性；采用结构函数的方法推导出截面的辐射修正公式，精确度达到了1％的水平，研究了真空极化给拟合公式带来的修正，并考虑了束流能散的影响，计算出最终的观测截面的解析近似式；对于三个共振态的拟合，针对不同的要求，采用了不同的拟合方法；同时在M.C。

Methods: 1. Experimental laparoscopic liver resection: We selected pigs as experimental models aiming to approach human beings physiological and anatomical condition. After CO2 pneumoperitoneum was established, the ligaments around liver were dissociated. Livers were cut off by the methods such as clamp dissection, microwave tissue coagulator, ultrasound dissector, Ligsure dissection, hand-assisted, short abdominal incision laparoscopy-assisted, and Endo-GIA switcher. The operation time and bleeding volume were compared between different methods of laparoscopic liver resection. The advantages and limitations of different methods were summarized. 2. Clinical laparoscopic liver resection: 15 cases with tumors in segment V of anterior right lobe or segments II, III of left lateral lobe or segment IV of left internal lobe were selected in this study. The liver diseases included hepatocellular cancer, hepatic cavernous hemangioma and hepatic focal nodular hyperplasia. The ligaments around liver were dissociated after CO2 pneumoperitoneum established. Laparoscopic liver resection were carried out by some of the methods combined such as clamp dissection, microwave tissue coagulator, hand-assisted, short abdominal incision laparoscopy-assisted, ultrasound dissector, rotation and suction dissector.

1、实验性腹腔镜肝切除：以猪为实验动物，旨在接近人体的生理、解剖环境下进行实验，建立操作空间后游离肝脏周围韧带，采用钳夹分离切肝法、微波刀切肝法、超声刀切肝法、Ligsure切肝法、手辅助腹腔镜肝切除法、小切口腹腔镜辅助切肝法、Endo-GIA切肝法等方法实施腹腔镜下肝切除，比较不同切肝方法的手术时间、出血量，总结各种方法的优越性及其局限性。2、临床腹腔镜肝切除：选择肿瘤位于肝右前叶第Ⅴ段、肝左外叶第Ⅱ、Ⅲ段及左内叶第Ⅳ段的15例患者，病种包括原发性肝癌、肝海绵状血管瘤、肝脏局灶性增生，建立气腹后游离肝脏周围韧带，采用钳夹分离断肝、微波刀固化后断肝、手辅助腹腔镜肝切除、小切口腹腔镜辅助肝切除、超声刀断肝、旋吸断肝等多种方法分离切线肝组织，暴露管道结构，再采用高频电凝、钛夹夹闭、缝扎止血、止血纱布覆盖、氩气刀止血、生物胶止血、Endo-GIA处理等多种方法相结合处理肝断面，统计手术完成情况、手术时间、手术出血量、术后并发症及术后住院时间等，评价腹腔镜肝切除的可行性及安全性。

This paper quantitates financial risk by constituting the model of measurement financial risk. And the samples are from the public companies'merger and acquisition from 2002 to 2005, this paper demonstrates perfectly the influence of financial risk of acquisition companies from different payment methods. The result of test analysis shows: in one side, the theory of risk-return is unfit in China (by being educed conclusions by other students: different payment methods bring different return, then the author detrusions different payment methods bringing different financial risk, and being tested direct proportion each other); in the other side, this paper answers different payment methods bringing different degree financial risk of acquisition companies: the smallest financial risk from cash payment method, the mean from commingle payment method, the biggest from stock payment method, which can supply reference in the choice of rational companies between payment methods and financial risk .

通过建立企业财务风险度量模型，将企业财务风险量化，并以中国上市公司2002年—2005年间的并购案中所采用的支付方式为样本，对我国上市公司并购中不同支付方式对并购方财务风险的影响做一个较系统、完善的实证检验，一方面从理论上验证了风险-收益理论的在我国的不具有适用性（通过对前人研究结论：不同支付方式带来不同收益，进而反推不同支付方式带来不同的财务风险，验证得出二者成正比关系）；另一方面回答在我国目前市场条件下并购中的不同支付方式引起收购公司不同程度的财务风险，其中现金支付方式下给收购公司带来的财务风险最小；混合支付次之，股票支付方式下财务风险最大，能给企业在并购时选择支付方式与财务风险的最佳组合提供参考。

Furthermore, the first-order optimality condition and its equivalent reformulations for generalized semi-infinite max-min programming with a non-compact set are presented using the lower-Hadamard directional derivative and subdifferential.2. Chapter 3 studies the gradient-type methods for unconstrained optimization problems. Section 1 proposes a new class of three-term memory gradient methods. The global convergence property of the method is established. Furthermore, in order to improve the convergence property of the method, a new class of memory gradient projection methods is presented with the property that the whole sequence of iterates converges to a solution to the problem under the conditions such as pseudo-convexity and continuous differentiability of objective function. In section 2, two new classes of methods, called gradient-type method with perturbations and hybrid projection method with perturbations, are proposed. In these methods, non-monotone line search technique is employed, which makes them easily executed in computer.

第3章研究了无约束优化问题的梯度型算法，第1节提出了一类新的三项记忆梯度算法，讨论了算法的全局收敛性，进一步提出了一类新的具有更好收敛性质的记忆梯度投影算法，并证明了该算法在函数伪凸的情况下具有整体收敛性，第2节在非单调步长搜索下提出了带扰动项的梯度型算法及其混合投影算法，这两类算法的一个重要特征就是步长采用线搜索确定而不象许多文献中那样要求步长趋于零，这样更容易在计算机上实现，在较弱的条件下证明了这些算法的全局收敛性，数值算例表明了算法的有效性。

In this paper, three methods for color image retrieval have been presented: hypercomplex SVD image retrieval, combination of hypercomplex convolution filter and hypercomplex SVD image retrieval and hypercomplex matrix correlation image retrieval. We made comparison among these hypercomplex-methods, and compared them with the traditional image retrieval methods. Experiment results showed that the hypercomplex-methods we presented in this paper could well conquer the problems existed in traditional image retrieval methods, and their retrieval results are much better. Meanwhile, this paper presented a new color image quality assessment based on hypercomplex SVD. It is a novel color image quality assessment that can be used as a graphical or a scalar measure to predict the distortion introduced by a wide range of noise sources. It reliably measures the distortion not only within a distortion type at different distortion levels, but also across different distortion types.

提出了超复数奇异值分解检索法，超复数卷积滤波与超复数奇异值分解相结合的检索法以及超复数矩阵相关检索法等三种超复数彩色图像检索方法，在对提出的三种算法进行比较的同时也将其与传统图像检索方法进行了比较，结果证明，超复数彩色图像检索法能较好地克服传统图像检索方法存在的问题，且检索结果更优；同时，本文提出了基于超复数奇异值分解的彩色图像质量客观评估法，这种全新的图形化与数值化相结合的方法不仅能够准确评估出彩色图像的不同失真等级，还能够区分不同的失真类型，从真正意义上实现了彩色图像的质量评估。

The thinking of this method as follows:Firstly,using single evaluation methods to evaluate.If the evaluation results aren\'t same,the Spearman rank correlation coefficient is used to calculate the correlation among the results of single evaluation methods.Based on the results,the traditional combined evaluation methods are used to combine the results of the single evaluation method.If the results of the upper combined methods are not same. Here the combined method evaluation indexes,such as Spearman rank correlation coefficient,correlation degree,the max deviation,average deviation,are used to evaluate the upper four combined evaluation methods.The entropy method is used to calculate the weights,and then get the final evaluation result.

首先，采用单一综合评价方法进行评价，对于不一致的评价结果，通过Spearman等级相关系数验证各单一评价方法间是否具有相关性；(来源：4dbdABbbC论文网www.abclunwen.com)对存在相关性的单一评价方法采用组合评价法对其结果进行组合，若所得评价结果仍不一致，采用Spearman等级相关系数、关联度、最大偏差、平均偏差对组合评价方法的组合效果进行评价，最后运用熵权法对上述组合评价进一步组合得到最终评价结果。

Distribution free statistical procedures or methods valid under nonrestrictive assumptions: basic tools; counting methods; order statistics, ranks; distribution free tests and associated interval and point estimators; sign test; signed rank tests; rank tests; Mann Whitney Wilcoxon procedures; Kolmogorov Smirnov tests; permutation methods; methods for discrete data with zeros and ties; computer techniques and programs; discussion and comparison with parametric methods.

非参数统计引论：无限制性假定时的无分布统计方法：基本工具，计数法，顺序统计量，秩，无分布检验与关联的区间估计和点估计，符号检验，符号秩检验，秩检验， Mann Whitney Wilcoxon 检验； Kolmogorov Smirnov 检验，排列检验法，含有零值和同分值的离散数据的处理方法；计算技术与编程，与参数方法的比较。

The phylogeny and applied prospect of MES are summarized in the paper. The principle of this system is analyzed from the point of view of acoustics. The surveying and filtering technology of auxiliary parameters, sounding data and the theory of image form, backscatter strength data processing, are researched deeply in the paper. The optimal model of velocity of sound is given. For sound ray tracing, some methods of correction of sound ray curve are developed. At the same time, an ideal model of sound ray tracing is proved and given. The GPS technology is applied for the determination of tide, attitude of vessel. Moreover, some methods are given. As an important topic, the systematic error is discussed in the paper. Some filtering methods are researched in this paper. Based on the current methods of image processing, the procedure and methods are tested and given that adapt to sonar image processing.

本文研究的工作是在总结多波束声纳测深系统的发展历史、应用前景的基础上，从声学角度分析了多波束系统的工作原理；对多波束辅助参数的测定和滤波方法、测深数据的滤波方法、多波束声纳图像的形成机理、图像处理以及最终应用等作了比较深入的研究；得出了适合于多波束精密深度计算的最优声速模型和声线改正模型；提出了 GPS 载波相位定位技术用于多波束辅助参数测量的思想、算法，改善了多波束系统的作业模式；系统地分析了深度数据的误差来源和类型，首次将系统误差作为影响测深精度的主要因素给以研究，并给出了削弱系统误差的方法，提高了深度数据的质量；对多波束声纳图像的形成、处理方法进行了细致的研究，给出了适合多波束图像处理的算法和流程，并从理论和实践上对声纳图像的应用进行了比较全面的研究。

In this thesis,the AM1,MNDO,MINDO/3(mainly AM1)and INDO/S-CI semiempirical MO methods were used toinvestigate the excited-state intramolecular protontransfer reactions of salicylic acid derivatives—salicylic acid,methyl salicylate,salicylaldehyde,o-hydroxyaceto-phenone,salicylamide and 3-hydroxy-picolinamide (6 conformers and 2-3 anion species);2-(2'-hydroxy-5' methylphenyl) benzotriazole(4 conformers),2-(2' hydroxyphenyl) benzimidazole (3 conformers and 3anion species),Bis-2,5-(2-benzoxazolyl)hydroquinone(3 conformers),2-(2'-hydroxyphenyl)benzothiazole(2conformers) and 7-azaindole dimer (2 conformers).Theinvestigations were described as follows.Geometry optimization,relative stability andhydrogen bonding energy First,for sylicylic acid derivative molecules,the AM1,MNDO and MINDO/3 methods were used toinvestigate ground-state geometry optimization,energies,relative stabilities and hydrogen-bondingenergies on the five kinds of the molecules(designing 6 conformers and 2-3 anion species).Comparing with experimental data,the optimizedgeometry,the order of stability,the hydrogen-bonding energies and the distances between O-O in O-H..O hydrogen bonds by AM1 method were in agreementwith the experimental data,however,the C-C bondlengths optimized by MNDO and MINDO/3 were longer,C-O and O-H bond lengths were shorter;for C-N bondlengths,the results opitimized by MNDO method werethe same as those by AM1 method,nevertheless the C-Nbond lengths given by MINDO/3 method were muchshorter.For some sylicylic acid derivatives(e.g.methyl salicylate,salicylamide),the order ofstabilities on the conformers given by MNDO andMINDO/3 methods were not in agreement with theexisting conformers deduced by experimental methods,and the hydrogen bonding energies calculated by MNDO.and MINDO/3 methods were smaller.Second,the studyon the other systems found that the optimizedgeometry of the proton-transfered product with INDOmethod could not be obtained,only could theoptimized geometry of reactant be obtained,and thecalculated hydrogen bonding energies were greater.Many results of calculation indicated that the studyon the excited-state intramolecular proton transferreaction system using AM1 method was suitable andreliable.

本论文用AM1、MNDO、MINDO/3（主要是AM1）和INDO/S-CI半经验分子轨道方法对水杨酸衍生物系列——水杨酸、水杨酸甲酯、水杨醛、O-羟基乙酰苯酮、水杨酰胺和3-羟基吡啶酰胺（6种异构体和2-3种阴离子）；2-（2'-羟基-5'-甲基苯基）苯并三〓唑（4种异构体）；2-（2'-羟基苯基）苯并咪唑（3种异构体和3种阴离子）；2，5-二间氮杂氧茚氢醌（3种异构体）；2-（2'-羟基苯基）间〓杂硫茚（2种异构体）和7-〓吲哚二体（2种异构体）的激发态分子内质子转移反应在以下几个方面进行了较系统的理论研究：几何构型优化和相对稳定性及氢键能首先以水杨酸衍生物系列分子为例，用AM1、MNDO和MINDO/3方法考察了5种分子（每种分子设计6种异构体和2-3种阴离子）的基态几何构型优化，能量、相对稳定性和氢键能计算，通过和实验数据进行比较，AM1方法给出的优化几何构型、稳定性次序、氢键能和O—H。。。O氢键的0—0距离与实验数据吻合最好，MNDO和MINDO/3方法优化的C-C键长偏长，C-O键和O-H键长偏短；对于C-N键长，MNDO和AM1优化结果差别不大，而MINDO/3给出了过短的C-N键长，MNDO和MINDO/3方法给出的有些水杨酸衍生物分子（如水杨酸甲酯和水杨酰胺）异构体的稳定性次序和实验上推测的可存在异构体结果不一致，MNDO和MINDO/3方法给出的氢键能偏低，对其他体系的研究发现INDO方法常常不能得到质子转移产物的优化几何构型，只能得到反应物的优化构型，并且估算的氢键能偏高，大量的计算结果表明AM1方法对本论文研究的激发态分子内质子转移反应体系是适宜和可靠的。

Research the nature of Earth's Physics and training to acquire seismic, gravity field, the Earth tide, the earth's rotation, and magnetic field, to power, plate tectonics and geophysical exploration geophysics, such as the branch's basic theory, observation instruments, methods of observation and data processing methods, able to independently complete a variety of geophysical observation and data-processing tasks, and with certain scientific research capacity of senior specialists.

主要研究地球的物理学性质，培养能掌握地震学、地球重力场、地球固体潮、地球自转、地磁场、地电、板块构造以及勘探地球物理等地球物理学各分支的基本理论、观测仪器、观测方法和数据处理方法，能够独立完成地球物理的各种观测和数据处理任务，并具有一定科研能力的高级专门人才。

Tom: You are right, he worked hard all the time.

你是对的。他一直都是努力工作。

Take shortcomings,failures,and mockings of others as commonplace and a drive to complete oneself,hold your own opinion over the evalution and disscution divested from others,afterwards sink into the state of eliminate mistakes if any or encourge oneself being not being influenced by the sayinngs of others or having no ideas to do.

把缺点、失败及别人的耻笑等看成是一种常事，当成完善自己的动力，对别人的评价和议论自己心中有主见，做到&有则改之，无则加勉&，不为人言所左右或无所适从。