首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 109 毫秒
1.
本文介绍了在Windows3.x下利用VisualBasic(VB)4.0高级程序设计语言开发多媒体程序的几种方法,首先从MCI指令入手,阐述了其基本含义,然后依次介绍了利用VB本身的MDI.VBX,动态连接库MMSYSTEM.DLL,AAPLAY.DLL以及SOUND.DRV来开发多媒体程序的方法,本文对于利用VB开发多媒体程序具有重要的指导意义。  相似文献   

2.
采用面向对象技术,以“119”模拟演练应用为目标,构造一个模拟演练课件模型,研究并实现1个基于OLE/COM的可视化多媒体创作平台VMPDP(VisualMultimediaPresentationDevelopingPlatform)。  相似文献   

3.
基于语义贴近度的模糊数据依赖   总被引:2,自引:0,他引:2  
刘惟一 《计算机学报》1997,20(8):725-730
本文基于语义贴近度的概念给出了模糊函数依赖(FFD)、模糊多值依赖(FMVD)和模型联接依赖(FJD)的定义。本文得到一组类似于Armstrong公理的正确、完备的FFD和FMVD的推理规则。进一步,我们证明了经典数据依赖满足模糊数据依赖的定义,FFD是FMVD的特例,而FMVD又是FJD的特例。  相似文献   

4.
安装ACTIVE PERL l由于 ULTIMATE BHLLETINBOARD MM.M*u CGI撰写的讨论区程序,因此如果要在WINDOWS环境下执行,就必须安装PERL执行程序。所以首先请到这里下载免费的ACTIVEPERL程序:HTTP://WWW.ACTIVESTATE.COM/DOWN-LOAD/ACTIVEPERL/WINDOWS/5.6/ACTIVEPERL-5.6.0.623-MSWIN32-X86-MULTI—THREAD.MSI。 下载完后,请直接执行ACTIVEPERL-5.…  相似文献   

5.
一种基于VRML的三维逼真地形生成方法   总被引:4,自引:1,他引:3  
本文首先对DEM数据进行处理,得到LOD模型;然后采用VRML和Java语言相结合的方法,在Client/Server上组成具有LOD功能的VRML文件;最后在Web上实现了三维地形场景的交互浏览。  相似文献   

6.
HZ(现在的标准是166MHz),带有300MHz RAMDAC(标准是350MH2的RAMDAC).没有TV-out输出接口。这种SE版本一定是流到市场上去的 OEM显卡,它看起来更像那些TNT2 M64和 Vanta显卡的地位.TNT2M64和VANTA也是标准TNT2的廉价版。 第二个令人惊奇的是.创通的 Annihilator SDR依然是最便宜的SDR显卡(国内可不是这样的情况).甚至比3D Prophet SE显卡的价格还要低,除了不太知名的VisionTek显卡,其他的SDR版本星卡价格…  相似文献   

7.
PJVM(ParalelJavaVirtualMachine)采用扩充Java语言功能的方法,提供了基于分布式共享存储器的编程接口DSM(DistributedSharingMemory)和基于消息传递的编程接口MPI(MessagePasingInterface),用户可以利用Java语言和扩充的两个编程接口,方便地设计在异构环境下运行的并行/分布程序。  相似文献   

8.
一款好的MODEM,不但能为你节省时间,而且还能节省宝贵的金钱。综观现时的MODEM市场,厂商品牌多至几十种,又有内置、外置、软猫等之别,速率更从33.6K到56K,令人眼花缭乱,难于抉择。 日前,我试用了一款型号为“SUPER5”(中译速霸)的内置MODEM,这是GVC(致福)公司新出品的一款速率为56K的中档产品,目前市场售价大约为210元。该款MODEM属于内置卡式结构,PCI接口,采用了型号为“RS56/SP-PCI”的ROCKWELL双频芯片组,能在 ITU-TV.90和 K56FLEX…  相似文献   

9.
作为视频点播(VIDEOONDEMAND)的一种替代品一准视频点播(NEARVIDEOONDEMAND)随着有关领域的发展已逐渐成为研究的热点。本文对基于CATV的NVOD系统结构进行分析,并对其中的关键技术进行了讨论。  相似文献   

10.
针对决策支持系统缺乏有效的决策过程控制手段的问题,提出了语义决策及其过程支撑环境(DPSE)的概念.DPSE 利用决策问题语义指导系统方案,以决策过程中行为为应激式调度,实现决策支持系统运行全过程中语义形式化.DPSE 将决策环境分为需求组织、资源分配和行为规划3个方面,并定义了语义决策过程中动态语义的表示方法,提供了语义封装的方法及其过程支撑相关的算法.最后给出了系统原型,并通过实验表明DPSE 的有效性.  相似文献   

11.
Security of autoregressive speech watermarking model under guessing attack   总被引:1,自引:0,他引:1  
The security of the "autoregressive (AR) watermark in AR host" signal model is investigated. It is demonstrated through analysis and Monte Carlo simulation that the AR watermarking model is asymptotically as secure as the "white watermark in white host" model under the guessing attack.  相似文献   

12.
13.
14.
This paper presents the development of a nonlinear model and of a nonlinear control strategy for a VARIO scale model helicopter. Our global interest is a 7-DOF (degree-of-freedom) general model to be used for the autonomous forward-flight of helicopter drones. However, in this paper we focus on the particular case of a reduced-order model (3-DOF) representing the scale model helicopter mounted on an experimental platform. Both cases represent underactuated systems ( for the 7-DOF model and for the 3-DOF model studied in this paper). The proposed nonlinear model possesses quite specific features which make its study an interesting challenge, even in the 3-DOF case. In particular aerodynamical forces result in input signals and matrices which significantly differ from what is usually considered in the literature on mechanical systems control. Numerical results and experiments on a scale model helicopter illustrate the theoretical developments, and robustness with respect to parameter uncertainties is studied.  相似文献   

15.
Linearly Combining Density Estimators via Stacking   总被引:1,自引:0,他引:1  
Smyth  Padhraic  Wolpert  David 《Machine Learning》1999,36(1-2):59-83
This paper presents experimental results with both real and artificial data combining unsupervised learning algorithms using stacking. Specifically, stacking is used to form a linear combination of finite mixture model and kernel density estimators for non-parametric multivariate density estimation. The method outperforms other strategies such as choosing the single best model based on cross-validation, combining with uniform weights, and even using the single best model chosen by Cheating and examining the test set. We also investigate (1) how the utility of stacking changes when one of the models being combined is the model that generated the data, (2) how the stacking coefficients of the models compare to the relative frequencies with which cross-validation chooses among the models, (3) visualization of combined effective kernels, and (4) the sensitivity of stacking to overfitting as model complexity increases.  相似文献   

16.
17.
A three-dimensional global ocean circulation model has been modified to run on the BBN TC2000 multiple instruction stream/multiple data stream (MIMD) parallel computer. Two shared-memory parallel programming models have been used to implement the global ocean model on the TC2000: the TCF (TC2000 Fortran) fork-join model and the PFP (Parallel Fortran Preprocessor) split-join model. The method chosen for the parallelization of this global ocean model on a shared-memory MIMD machine is discussed. The performance of each version of the code has been measured by varying the processor count for a fixed-resolution test case. The statically scheduled PFP version of the code achieves a higher parallel computing efficiency than does the dynamically scheduled TCF version of the code. The observed differences in the performance of the TCF and PFP versions of the code are discussed. The parallel computing performance of the shared-memory implementation of the global ocean model is limited by several factors, most notably load imbalance and network contention. The experience gained while porting this large, real world application onto a shared-memory multiprocessor is also presented to provide insight to the reader who may be contemplating such an undertaking.  相似文献   

18.
A neural network auto regressive with exogenous input (NNARX) model is used to predict the indoor temperature of a residential building. Firstly, the optimal regressor of a linear ARX model is identified by minimising Akaikes final prediction error (FPE). This regressor is then used as the input vector of a fully connected feedforward neural network with one hidden layer of ten units and one output unit. Results show that the NNARX model outperforms the linear model considerably: the sum of the squared error (SSE) is 15.0479 with the ARX model and 2.0632 with the NNARX model. The optimal network topology is subsequently determined by pruning the fully connected network according to the optimal brain surgeon (OBS) strategy. With this procedure near 73% of connections were removed and, as a result, the performance of the network has been improved: the SSE is equal to 0.9060.  相似文献   

19.
Efficiency enhancement techniques—such as parallelization and hybridization—are among the most important ingredients of practical applications of genetic and evolutionary algorithms and that is why this research area represents an important niche of evolutionary computation. This paper describes and analyzes sporadic model building, which can be used to enhance the efficiency of the hierarchical Bayesian optimization algorithm (hBOA) and other estimation of distribution algorithms (EDAs) that use complex multivariate probabilistic models. With sporadic model building, the structure of the probabilistic model is updated once in every few iterations (generations), whereas in the remaining iterations, only model parameters (conditional and marginal probabilities) are updated. Since the time complexity of updating model parameters is much lower than the time complexity of learning the model structure, sporadic model building decreases the overall time complexity of model building. The paper shows that for boundedly difficult nearly decomposable and hierarchical optimization problems, sporadic model building leads to a significant model-building speedup, which decreases the asymptotic time complexity of model building in hBOA by a factor of to where n is the problem size. On the other hand, sporadic model building also increases the number of evaluations until convergence; nonetheless, if model building is the bottleneck, the evaluation slowdown is insignificant compared to the gains in the asymptotic complexity of model building. The paper also presents a dimensional model to provide a heuristic for scaling the structure-building period, which is the only parameter of the proposed sporadic model-building approach. The paper then tests the proposed method and the rule for setting the structure-building period on the problem of finding ground states of 2D and 3D Ising spin glasses.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号