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1.
基于虚拟现实的供应链可视化仿真技术研究   总被引:3,自引:0,他引:3  
探讨了基于虚拟现实的供应链可视化仿真方法.介绍了可视化供应链仿真的策略;重点论述了供应链可视化仿真的实现过程,具体包括三维实体几何模型的生成,供应链仿真模型的建立以及仿真运行,最后以某注塑机供应链可视化仿真为例验证了该仿真方法的有效性.  相似文献   

2.
WITNESS环境下基于改进型IDEF3方法的离散事件仿真建模   总被引:2,自引:0,他引:2  
针对WITNESS仿真环境下,复杂离散事件仿真建模过程中出现的大量顺序、并行、同步、冲突及因果依赖等关系,提出采用改进型IDEF3方法进行仿真建模.采用仿真规则与交汇点集成、行为单元与仿真信息数据集成的原则进行建模;同时在IDEF3方法的基础上,建立新的行为单元,达到了仿真单元的可重用和可重构性,大大提高了仿真建模的速度,减少了建模难度.最后,给出了在改进型IDEF3方法下进行离散事件仿真的框架,并在仿真软件WITNESS的基础上,通过实例详细描述了建模过程.  相似文献   

3.
提出了一种新的C—MEX S函数异步电机参数时变仿真模型,可模拟电机各参数的变化,精度高、仿真速度快,克服了现有的参数定常异步电机仿真模型及M文件S函数仿真模型的缺点。对比仿真验证了该模型的正确性和快速性,仿真示例表明了该模型的有用性和有效性,为矢量控制相关问题的研究提供了一个更接近真实电机行为特性的高效仿真模型。  相似文献   

4.
在仿真的效率和可扩展性方面,单纯的数据包仿真已无法满足网络发展的需要.该文将流仿真模型嵌套到数据包仿真的程序中,实现了流仿真同数据包仿真的集成.在仿真中,流网络通过流链路链接到包级仿真的Ns节点上,这种采用集成混合模型进行的网络仿真,既保持了数据包仿真的参数精确性,又提高了仿真效率.实验结果表明:采用混合模型仿真TCP流可以获得正确的动态特性;混合模型仿真可以提高网络的仿真效率,提高的程度与采用数据包仿真流所占整个TCP流的比例有关.  相似文献   

5.
功率因数可调的电压型三相PWM整流器的仿真研究   总被引:1,自引:0,他引:1  
分析了功率因数可调的基本原理,基于Matlab建立了PWM可逆整流器的数学模型和结构模型两种仿真模型,提出了实现功率因数可调的技术方案。分别时两种模型作了仿真研究,给出了仿真结果,对所建立的仿真模型作了验证。仿真结果表明,功率因数连续调节是可行的。  相似文献   

6.
雷达组网仿真研究与实现   总被引:3,自引:0,他引:3  
针对工程中雷达组网的实际情况,研究了雷达组网技术的仿真与实现问题。首先基于分布式组网结构对雷达进行布站和组网,然后采用静态和动态相结合的仿真方法,实现了雷达探测仿真与数字地理信息系统的结合,创建了集雷达性能仿真、环境仿真、电子对抗仿真和目标仿真于一体的雷达探测模型体系;建立了雷达组网动态仿真多因子评估指标体系和评价方法。仿真试验表明,该雷达仿真系统具有优良的模拟实际作战性能。  相似文献   

7.
火炮射击精度仿真研究   总被引:2,自引:0,他引:2  
该文对火炮射击精度计算机仿真方法进行研究,包括仿真方法和射击精度仿真等内容。该文先对影响射击精度的各种射击环境参数进行分析,从而给出了其概率特征和仿真时的随机取值,然后仿真每次的射击结果,进而求出射击精度。该仿真方法避免了近似计算中存在的相关性误差,提高了仿真结果的精度。  相似文献   

8.
基于面向对象的交通仿真研究   总被引:3,自引:0,他引:3  
针对目前国内城市交通仿真发展的不足,提出了基于面向对象的交通仿真研究方向,并对城市交通仿真的重要组成部分平面交叉口的仿真做了初步的基于面向对象的研究,提出了平面交叉口仿真的模型和仿真流程。在此基础上,可进一步做整个交通仿真系统的研究,以满足我国经济发展的需要。  相似文献   

9.
首先用面向对象的方法设计了一个离散事件仿真核,然后将该仿真核应用于VHDL仿真中.由于对离散事件系统进行了合理的抽象以及仿真核提供了简便的编程接口,所以降低了VHDL仿真系统建模的复杂性,并使得VHDL仿真系统具有良好的可维护性和可扩展性.该仿真核还可以应用到其它的离散事件系统仿真场合.  相似文献   

10.
基于Multi-Agent的公路仿真系统框架   总被引:5,自引:0,他引:5  
为了建立公路仿真系统对公路设计的合理性进行评价,研究了公路仿真系统结构问题。公路仿真系统是连续变量动态系统和离散事件动态系统相互作用的混杂系统,通过分析公路仿真系统的特征,建立基于Multi-Agent理论的公路仿真系统框架。将系统划分为3类相互作用的A-gent,即反应Agent、合作Agent和界面Agent,给出了适合公路仿真特点的Agent元定义,建立了各Agent的协商模型,并对其运行机制进行了讨论。该仿真框架的建立,从软件工程的角度解决了仿真过程中混杂性的问题,对于合理设计仿真系统结构具有重要作用。  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.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
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   

15.
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   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
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   

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