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1.
一种光突发交换中的分组调度算法   总被引:1,自引:0,他引:1  
分析了传统光突发交换中的分组调度算法——LAUC算法的缺陷,提出了一种LAUC算法的改进算法(LAUC-SV算法),采用自相似业务流模型对两种算法的性能进行了模拟仿真,结果表明在同等条件下LAUC-SV算法下的丢包率比LAUC算法低10^0.5,且新算法下的丢包率关于光纤延时线单元时间的最佳窗口大大展宽,而新算法的复杂度与LAUC算法相比仅呈现线性增长关系.  相似文献   

2.
为探索新的程度粗糙集拓展模型,基于程度的逻辑或需求,提出了程度上下近似算子的逻辑或运算模型。在该模型中,研究了程度上下近似算子的逻辑或运算的本质、基本结构与性质,提出了宏观算法与结构算法,进行了算法分析与比较,得到了结构算法比宏观算法更具空间优势的结论。最后用实例对程度上下近似算子的逻辑或运算模型及其算法进行了说明。  相似文献   

3.
基于程度的逻辑差需求,提出了程度上下近似算子的逻辑差运算模型.在该模型中,研究了程度上下近似算子的逻辑差运算的本质、基本结构与性质,提出了宏观算法与结构算法,进行了算法分析与比较,得到了结构算法比宏观算法更具优势的结论.最后用实例对程度上下近似算子的逻辑差运算模型及其算法进行了说明.程度上下近似算子的逻辑差运算模型,对粗糙集模型的理论发展与量化应用具有意义.  相似文献   

4.
鉴于二维坐标下无线定位算法的结果与现实环境有一定的差距,提出了一种在三维空间条件下基于到达时间(TOA)的Chan推广算法。深入比较和分析了影响该算法定位精度的因素,总结了该算法适用的定位条件和定位环境。在不同定位基站数目、待定位移动台的位置和参与定位基站布局等条件下,对该算法进行了大量的模拟仿真,结果表明利用该算法定位结果比较准确,算法有效可行。  相似文献   

5.
基于互耦矩阵的特殊结构,提出了两种在未知互耦条件下改进的均匀线阵波达方向估计算法.为了提高在未知互耦条件下波达方向估计算法的性能,提出了一种采用空间平滑的改进算法.由于未采用迭代算法,从而降低了算法运算复杂度.仿真实验证实了该算法的有效性.  相似文献   

6.
黄红卫 《甘肃科技》2014,30(17):13-15
针对雷达目标,观测和处理了在不同坐标系下的数据,提出了一种混合坐标系下的自适应α-β滤波算法来跟踪机动目标。该算法以自适应α-β滤波器为基础,将直角坐标系和球面坐标系下的算法相结合,克服了这两种坐标系下滤波算法的不足,对机动目标有很好的跟踪效果。仿真表明,该算法的跟踪性能优于单一坐标系下的自适应α-β滤波器,尤其适用于TWS雷达多机动目标跟踪情况。  相似文献   

7.
给出了一类在非精确线搜索下的混合共轭梯度算法,对李荣生提出的NCG算法进行了改进,在算法的迭代过程中,保持了迭代方向的下降性,在较弱的条件下证明了全局收敛性,数值试验表明该算法是相当有效的.  相似文献   

8.
高瑜  黄森  陈刘鑫  黄军虎 《科学技术与工程》2020,20(28):11605-11611
为了提高微电网的日运转经济效益,本文构建了并网模式下交流微电网运转结构图,建立了并网模式下交流微电网日优化经济调度数学模型,该模型包含有多个子目标函数、多个约束条件。针对传统灰狼优化算法无法很好均衡算法的全局寻优能力和局部寻优能力,寻优精度差的问题,引进一种基于非线性变化的收敛因子均衡算法的全局寻优能力和局部寻优能力,从而提高灰狼算法的寻优精度。采用改进的灰狼算法和原始灰狼算法对四个基准测试函数进行仿真,实验结果表明改进灰狼算法相较于原始灰狼算法能够获得更优解,初步证实了改进灰狼算法的可行性及优越性,再将改进灰狼算法和原始灰狼算法分别应用于并网模式下交流微电网日优化数学模型求解,通过对仿真结果对比分析,证实了改进灰狼算法的确能够更好的提高并网模式下交流微电网的日运转经济效益。  相似文献   

9.
为研究机器学习在算法稳定框架下的推广能力,提出了变一误差估计条件下联合算法稳定的概念,并利用广义的McDiarmid不等式得到了机器学习在联合算法稳定下变一推广误差的界.  相似文献   

10.
高动态条件下,传统圆锥补偿算法存在不可交换性误差。为抑制圆锥误差,提出了基于角速率输出的等效旋转矢量三子样二次迭代优化算法;并采用修正型罗德里格斯参数进行更新,推导了相应的圆锥补偿算法方程和表达式。在不同圆锥运动频率下和不同更新频率下,仿真验证得出了改进算法在精度和稳定性方面均较四元数法、三子样算法均有提高。实测结果表明,改进算法受圆锥半角、圆锥运动频率的影响较小,在高动态条件下较传统算法性能更优。  相似文献   

11.
海德格尔对荷尔德林诗歌的阐释,目的是进行诗与思的对话,归根结底还是探讨存在。诗与“在”的关系,是海氏诗学框架的核心内容,诗与“在”的关系又进一步引申为艺术与真理的关系,本从真理如何被遮蔽的问题入手,试图读解海德格尔诗学的内涵。艺术是无蔽的真理显明的一种方式,诗是危机的拯救,语言是存在的家园。海德格尔对诗与在的探讨最后又转入了对语言的探讨,无法走出语言的牢笼。只有在实践中,把艺术变成为社会变革的一个因素,才可以解放被传统理性压迫的力量,显现艺术的真理,确立艺术的价值。  相似文献   

12.
Canonical Wnt/β-catenin pathway plays a central role in development, homeostasis, as well as tumorigenesis. The regulation of the pathway involves various and complicated mechanisms, including the extracellular, intracellular and endonuclear regulation. As the key component of the pathway, the Lefl/Tcfs-β-catenin complex is also the key target of regulation in the nucleus. In the current review, we are going to summarize the regulators in the nucleus which can modify the transcrip- tional activity of the Wnt/β-catenin pathway.  相似文献   

13.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

14.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

15.
信托财产是信托关系的基本要素,由于信托的特殊性,信托财产与传统民法的财产有很大区别,正确给信托财产定位,是信托业得以健康发展的核心问题。信托财产的特性在于其人格性,而这种人格性的赋予是以交易成本最小化为动因,尽管信托财产人格性设计对受益人的利益有偏袒,但从社会成本而言,其目的在于促使交易成本最小化,当然,对信托财产的人格性不能绝对化,由于利益平衡的需求,往往在特定情况下对信托财产予以人格否认。  相似文献   

16.
本文通过测量金属晶体电极表面的微分电容研究了金属电极表面在金属与水溶液界面上的吸附能力,以及金属与吸附质之间的相互作用。文中论述了多晶铜电极在(0.5-x)mNaClO_4+xmNaBr的一系列不同x值的溶液中的微分电容测量值及微分电容-电位曲线,证明了F~-和ClO_4~-离子在多晶铜电极表面是非常弱的吸附,Br~-离子在多晶铜电极表面具有特定的吸附,每条电容-电位曲线有一个凸起的峰。在峰所对应的位能值,金属表面对阴离子的吸附能力强,证实金属-吸附质之间的相互作用强,吸附的阴离子在过渡层中散射导电电子的能力也强。对于相同阴离子和金属的体系,其微分电容与吸附质的浓度、电压、溶液的pH值和表面的非均匀性等因素密切有关。研究证明,金属晶体电极表面在电解质溶液中的微分电容的变化规律类似于表面电反射信号的强弱变化规律,微分电容大小取决于金属-吸附质之间的电荷转移程度。  相似文献   

17.
阴离子表活剂压裂液是新型清洁压裂液,原油和地层水对其破胶机理与实验研究已相当充分,但气体对其破胶作用至今研究很少.为解决阴离子表活剂压裂液在压裂应用中的障碍,研究采用一套实用的实验流程,评价了天然气、氮气、二氧化碳三种常见气体对阴离子表活剂压裂液的影响.实验证明,三种不同的气体对阴离子表活剂压裂液的降粘幅度存在较大的差别,其中,二氧化碳气体对阴离子清洁压裂液降粘幅度最大,可使交联液体彻底破胶,天然气对阴离子型表活剂压裂液降粘幅度较小,氮气对阴离子压裂液的粘度几乎没有影响,氮气和天然气可以使液体泡沫化,从而有利于返排.实验结果为优化压裂设计提供了依据,可有效提高现场压裂施工成功率.  相似文献   

18.
介绍了速调管在我国的发展现状和几种不同结构的多腔速调管的主要特性比较,并给出了小信号条件下速调管的各种主要特性的简化分析方法.在这种简化分析方法中,把多腔速调管看作是几个双腔速调管的级联,并且没有考虑非线性、空间电荷效应和相对论效应等带来的影响,目的是阐述基本原理和基本分析方法.  相似文献   

19.
Deposition of granular materials into a container is a general industrial packing process. In this study, the deposition behaviour of dilute granular mixtures consisting of two types of particles that were of the same particle size but different particle densities in the presence of air was numerically analyzed using a coupled discrete element method (DEM) and computational fluid dynamics (CFD). Bilayer granular mixtures with light particles at bottom and heavy particles at top were first simulated. It was found that the presence of air significantly affected the flow behaviour of the bilayer mixtures. For the system with a relatively low initial void fraction, the air entrapped inside the container escaped through the dilated zones induced due to the friction between the powder bed and wall surfaces. The escaping air streams entrained light particles that were originally located at the bottom of the granular system. Consequently, these light particles were migrated to the top of the granular bed at the end of deposition process. More light particles were migrated when the deposition distance was increased. For the system with a high initial void fraction, some light particles penetrated into the top layer of heavy particles and created a mixing zone. Deposition of random mixtures with different initial void fractions was also investigated and the influence of initial void fraction on the segregation behaviour was explored as well. It was found that the increase of void fraction promoted segregation during the deposition in air. It was demonstrated that, for granular mixtures consisting of particles of different air sensitivities, the presence of air had a significant impact on the mixing and segregation behaviour during the deposition.  相似文献   

20.
Subjective logic provides a means to describe the trust relationship of the real world.However,existing fusion operations it offers treat fused opinions equally,which makes it impossible to deal with the weighted opinions effectively.A.Jφsang presents a solution,which combines the discounting operator and the fusion operator to produce the consensus to the problem.In this paper,we prove that this approach is unsuitable to deal with the weighted opinions because it increases the uncertainty of the consensus.To address the problem,we propose two novel fusion operators that are capable of fusing opinions according to the weight of opinion in a fair way,and one of the strengths of them is improving the trust expressiveness of subjective logic.Furthermore,we present the justification on their definitions with the mapping between the evidence space and the opinion space.Comparisons between existing operators and the ones we proposed show the effectiveness of our new fusion operations.  相似文献   

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