Proceedings of the Nineteenth National Radio Science Conference最新文献

On the optimal choice of wavelet bases and signal compression using the wavelet lifting scheme 研究了小波基的优化选择和小波提升方案对信号的压缩

Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022652

M. Fahmy, G. El-Raheem, Y.M. Yaseen, A.A. Sommia

{"title":"On the optimal choice of wavelet bases and signal compression using the wavelet lifting scheme","authors":"M. Fahmy, G. El-Raheem, Y.M. Yaseen, A.A. Sommia","doi":"10.1109/NRSC.2002.1022652","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022652","url":null,"abstract":"A simple method is proposed for the design of biorthogonal wavelet bases. Starting from any simple orthogonal wavelets and using the wavelet lifting scheme, we show that new, completely arbitrary, biorthogonal wavelets can be constructed to suit any specific design specification. Two specific applications are considered. The first is to design biorthogonal filter banks with a perfect reconstruction (PR) property. The second application lies in choosing the best wavelet bases for signal compression. In the first application, it is shown that, unlike traditional orthogonal QMF banks, where the analysis and synthesis filters are closely related, biorthogonal filter banks have the feature that the analysis and synthesis filters can be freely chosen to meet any design specifications, while maintaining the perfect reconstruction property. The flexibility in designing these filter banks is achieved by optimizing the parameters of the lifting scheme used in their construction. In the denoising application, the strategy is to use the lifting scheme to get the optimum wavelet bases that lead to the minimum energy norm L/sub 2/ up to scale L. Illustrative examples are given to demonstrate the simplicity and efficiency of the proposed design approach.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127317712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Switched capacitor circuits and their applications, an overview 开关电容电路及其应用综述

Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022606

E. Saad

引用次数: 0

An integrated space/terrestrial cellular architecture with different priority schemes for global mobile communications 具有不同优先级方案的综合空间/地面蜂窝结构，用于全球移动通信

Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022641

S. E. El Dolil, A. Nofal, W. Al-Hanafy

{"title":"An integrated space/terrestrial cellular architecture with different priority schemes for global mobile communications","authors":"S. E. El Dolil, A. Nofal, W. Al-Hanafy","doi":"10.1109/NRSC.2002.1022641","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022641","url":null,"abstract":"A multiple hierarchical cellular structure is proposed to handle the teletraffic load resulting from different user densities. In the lowest hierarchical level, microcells serve the highest teletraffic density, while overlaying macrocells serve both calls from areas that are difficult to be covered by microcells, as well as overflow traffic from microcells. At the highest hierarchical level, nongeostationary satellites focus their spotbeams to serve satellite-only users sparsely distributed and act as teletraffic relief for the terrestrial segment. At each hierarchical level different priority schemes are used to privilege handoff requests. A reserved channel scheme (RCS) is applied in the microcell layer, both RCS and a sub-rating scheme (SRS) are used in the macrocell layer, while in the spotbeam cell layer, RCS, SRS, and a queuing priority scheme (QPS) are implemented. An analytical teletraffic model is developed to evaluate the proposed architecture. Numerical results are presented and discussed for the new call blocking, handoff failure, forced termination and noncompletion probabilities.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125318253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Simulation and performance of a microwave magnetic sensor 微波磁传感器的仿真与性能研究

Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022661

A. Abou-Elnour, M. Ibrahim, E.Y. Mohamed

引用次数: 0

A SOFT-backpropagation algorithm for training neural networks 神经网络训练的软反向传播算法

Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022647

M. El Adawy, M. Aboulwafa, H. Keshk, M.M. El Tayeb

{"title":"A SOFT-backpropagation algorithm for training neural networks","authors":"M. El Adawy, M. Aboulwafa, H. Keshk, M.M. El Tayeb","doi":"10.1109/NRSC.2002.1022647","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022647","url":null,"abstract":"The backpropagation (BP) algorithm is a one of the most common algorithms used in the training of neural networks. The single offspring technique (SOFT algorithm) is a new technique (see Likartsis, A. et al., Proc. 9th Int. Conf. on Tools with Artificial Intelligence, p.32-6, 1997; Yao, X., Proc. IEEE, vol.87, p.1425-47, 1999) of applying the genetic algorithm in the training of neural networks which reduces the training time as compared with the backpropagation algorithm. We introduce a new technique. This technique is a hybrid SOFT-BP algorithm where the SOFT-algorithm is applied first to obtain an initially good weight vector. This vector is introduced to the backpropagation algorithm, which improves the precession of the weight vector to reach an acceptable error limit. The results show an acceptable improvement in the training speed for the hybrid technique as compared with the individual backpropagation or SOFT algorithm. We also study the success ratio (how many times the algorithm succeeds in finding a solution to the total number of trials) for the new hybrid algorithm. A recommended range of the switching error limit at which to switch from the SOFT algorithm to the BP algorithm is suggested.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124776280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

High efficiency silicon MIS/IL solar cells under external back bias 外背偏置下的高效硅MIS/IL太阳能电池

Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022663

A.K. Abou Alsoud, N. Elfaramawy, M. Attala, A. Hafez

引用次数: 0

On-line prediction of photovoltaic output power under cloudy skies by using fuzzy logic 基于模糊逻辑的多云天气下光伏输出功率在线预测

Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022662

I. Morsy, A. K. Aboul Seoud, A. El Zawawi

引用次数: 7

Multi-band based recognition of spoken Arabic numerals using wavelet transform 基于小波变换的阿拉伯语口语数字多波段识别

Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022626

W. Alkhaldi, W. Fakhr, N. Hamdy

引用次数: 12

Effect of the buffer layer on the microwaves properties in the coplanar waveguide for LiNbO/sub 3/ optical modulators with superconducting electrodes 缓冲层对超导电极LiNbO/ sub3 /光调制器共面波导微波特性的影响

Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022664

T. E. Taha, K.A. Mostafa, A.A. Aboul-Enien

引用次数: 0

Shielding effectiveness of reinforced concrete structures in cellular communication bands 钢筋混凝土结构在蜂窝通信波段的屏蔽效能

Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022621

H. Elkamchouchi, A. Abdelkader

引用次数: 10