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1.
高速的多DSP并行处理技术是软件无线电关键技术之一.近年来,为了解决这一难题,提出了多种设计方案.该文以基于交换网络结构的方案作为研究重点,在此基础上提出一种改进型的交换网络结构,研究了该种结构核心器件——适配器的设计,在该新型结构上实现TCP/IP协议.最后,分析该新型结构的性能,并与最初的交换网络结构做了比较.  相似文献   

2.
多协议标签交换(MPLS)网络层协议结合了异步交换模式(ATM)的交换技术和IP协议的路由技术,被认为是未来网络的关键协议。在介绍了多协议标签交换协议、综合服务模型IntServ和差分服务模型DiffServ两种服务模型工作原理和网络结构的基础上,重点对综合服务模型和差分服务模型在MPLS中的应用进行分析。最后对目前广泛应用的SLA协议进行简要介绍。  相似文献   

3.
为了给软件无线电的研究提供一个测试平台,设计实现了一个多数据通道高速互连背板平台.背板平台包括传输母板、时钟分配板和数据通道交换板,并提供ADC,DDC,DSP,DUC和DAC单板接口.通过采用高性能芯片和合理的高速设计方法,实现了背板平台良好的传输误码率和时钟晃动性能以及多个数据通道的自定义总线形式.  相似文献   

4.
提出了一种基于多DSP混合结构的Gabor小波神经网络图像目标识别新方法.利用TMS320C5409设计了多DSP混合结构系统,根据并-串结构系统的特点,设计了Gabor小波神经网络算法.算法被分成不同的并-串结构进行运算,利用串行的DSP-1进行Gabor小波变换提取图像目标的特征向量,并输入到采用不同网络结构的并行多DSP进行BP网络运算,串行的DSP6对BP网络输出的后验概率进行加权平均,给出分类结果.对9种飞机目标进行了分类识别仿真实验.实验结果表明,该方法应用于多目标识别时,识别时间为2.8 ms,识别率达到98%.  相似文献   

5.
随着微电子技术和微处理机技术的迅速发展,采用分布式控制的大容量数字程控交换系统不断出现,并日趋完善,本文着重阐述分布式控制的实现技术,包括模块划分、自主控制机理、数据分布、通信方式等方面,以及对分布式控制起支持作用的交换网络结构。  相似文献   

6.
为实现小波包多载波调制,设计了小波包多载波调制的DSP实现方案.采用一种等效结构,将小波包多我波调制转化为串/并变换、小波包综合和脉冲成形3个环节,小波包综合和脉冲成形由小波包快速算法(Mallat算法)实现.以高速浮点DSP为硬件平台,编程采用软件流水优化和DMA技术.利用Mallat算法的特点,采用交替组合法使算法中乘法的运算量减半.所设计的软件在TMS320C6701EVM评估板上成功实现实时运行.CCS环境下的实测结果表明:软件流水方法产生目标代码的运行效率已接近该DSP的最高性能.  相似文献   

7.
论述了nⅹm涡卷的蔡氏混沌方程的构造方法,设计了一种多涡卷混沌吸引子在DSP上实现的系统.该系统以TMS320C6713DSP为硬件核心,应用CCSv 3.3软件及DSP/BIOS操作系统,通过在Matlab中的CCSLink工具调试,把DSP运行的数据交给Matlab进行分析,从而更加快速方便地完成较复杂系统的开发.  相似文献   

8.
船岸一体化机务管理系统的设计   总被引:1,自引:0,他引:1  
在分析了目前国内多家航运企业船舶管理工作机制的基础上,提出了一个以远程通信为基础、通过船岸数据交互共享实现船舶设备保养、备件物料供应的管理信息系统,阐述了该系统的通信方式、网络结构及功能模型.通过该系统实现了船舶设备及备件管理工作的计划、控制及信息共享.  相似文献   

9.
由于间接式功交换网络在工业上应用广泛,提出了基于超结构模型的间接式功交换网络综合方法.通过构建分级超结构,以年度总费用最小为目标建立了混合整数非线性规划模型.根据设备操作曲线提出压力与流量的约束,实现了间接式功交换网络中流股间的可行匹配,得到了最优功交换网络结构.算例结果分析表明,最优功交换网络结构的年度总费用比未进行流股匹配的基础结构减少了29.04%,验证了模型的有效性与网络结构优化的可行性.  相似文献   

10.
DSP在控制系统中应用越来越广泛,基于DSP中2000系列数字信号处理器的强大控制功能,本设计利用DSP2407的PWM多路输出方法控制步进电机的驱动,可以实现两自由度步进电机同时工作。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
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   

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