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合成作战单元抢滩阶段作战编波冲击及方案优化模型 被引量:1
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作者 聂文兵 冯进 《火力与指挥控制》 CSCD 北大核心 2021年第12期128-132,共5页
如何科学、量化进行编波冲击是影响和制约合成作战单元抢滩阶段战斗的焦点问题、瓶颈所在。通过分析研究影响编波冲击的主客观因素,建立了合成作战单元抢滩阶段作战编波冲击模型,提出了基于“和数分解”的多目标优化搜索算法,并结合算... 如何科学、量化进行编波冲击是影响和制约合成作战单元抢滩阶段战斗的焦点问题、瓶颈所在。通过分析研究影响编波冲击的主客观因素,建立了合成作战单元抢滩阶段作战编波冲击模型,提出了基于“和数分解”的多目标优化搜索算法,并结合算例对模型的有效性和可信性进行了验证,对编波方案的价值进行了评价和优化分析。 展开更多
关键词 合成作战单元 编波冲击 和数分解 方案优化 多目标优化搜索算法
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VLSI Implementation of a Wavelet Image Coder
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作者 乔世杰 王国裕 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第7期695-700,共6页
A modular architecture for two dimension (2 D) discrete wavelet transform (DWT) is designed.The image data can be wavelet transformed in real time,and the structure can be easily scaled up to higher levels of DWT.A f... A modular architecture for two dimension (2 D) discrete wavelet transform (DWT) is designed.The image data can be wavelet transformed in real time,and the structure can be easily scaled up to higher levels of DWT.A fast zerotree image coding (FZIC) algorithm is proposed by using a simple sequential scan order and two flag maps.The VLSI structure for FZIC is then presented.By combining 2 D DWT and FZIC,a wavelet image coder is finally designed.The coder is programmed,simulated,synthesized,and successfully verified by ALTERA CPLD. 展开更多
关键词 discrete wavelet transform zerotree image coding VLSI Verilog HDL CPLD
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Efficient Quadtree based Fractal Image Coding Scheme in Wavelet Transform Domain *
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作者 高西奇 洪波 +1 位作者 张辉 何振亚 《Journal of Southeast University(English Edition)》 EI CAS 1998年第1期35-40,共6页
This paper presents an efficient quadtree based fractal image coding scheme in wavelet transform domain based on the wavelet based theory of fractal image compression introduced by Davis. In the scheme, zerotrees of... This paper presents an efficient quadtree based fractal image coding scheme in wavelet transform domain based on the wavelet based theory of fractal image compression introduced by Davis. In the scheme, zerotrees of wavelet coefficients are used to reduce the number of domain blocks, which leads to lower bit cost required to represent the location information of fractal coding, and overall entropy constrained optimization is performed for the decision trees as well as for the sets of scalar quantizers and self quantizers of wavelet subtrees. Experiment results show that at the low bit rates, the proposed scheme gives about 1 dB improvement in PSNR over the reported results. 展开更多
关键词 fractal image coding wavelet transform QUADTREE
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A VIDEO SPECTRUM SPLITTING ENCODING SCHEME BASED ON HUMAN VISION AND ITS COMPUTER SIMULATION
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作者 赵宇 李华 +1 位作者 俞斯乐 滕建辅 《Transactions of Tianjin University》 EI CAS 1995年第1期79+76-79,共5页
In this paper, a 3-D video encoding scheme suitable for digital TV/HDTV (high definition television) is studied through computer simulation. The encoding scheme is designed to provide a good match to human vision. Bas... In this paper, a 3-D video encoding scheme suitable for digital TV/HDTV (high definition television) is studied through computer simulation. The encoding scheme is designed to provide a good match to human vision. Basically, this involves transmission of low frequency luminance information at full frame rate for good motion rendition and transmission of high frequency luminance signal at reduced frame rate for good detail in static images. 展开更多
关键词 D video encoding discrete wavelet transform human vision computer simulation
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APPLICATION AND IMPLEMENTATION OF REAL-TIME IMAGE ZOOMING WITH THE WALSH TECHNIQUE
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作者 江洁 郁道银 《Transactions of Tianjin University》 EI CAS 2001年第4期229-232,共4页
Based on the study of Walsh transformation,the zooming template of a two dimensional superimposure filter is decomposed and simplified,and it is real time implemented with FPGA.This method is simple and effective.Th... Based on the study of Walsh transformation,the zooming template of a two dimensional superimposure filter is decomposed and simplified,and it is real time implemented with FPGA.This method is simple and effective.The quality of the image is very good. 展开更多
关键词 image zooming two dimensional superimposure filter field programmable gate array (FPGA)
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Method of combining space-time block coding with adaptive beamforming
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作者 沈克勤 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期254-259,共6页
A method of space-time block coding (STBC) system based on adaptive beamforming of cyclostationarity signal algorithm is proposed.The method uses cyclostationarity of signals to achieve adaptive beamforming,then con... A method of space-time block coding (STBC) system based on adaptive beamforming of cyclostationarity signal algorithm is proposed.The method uses cyclostationarity of signals to achieve adaptive beamforming,then constructs a pair of low correlated transmit beams based on beamform estimation of multiple component signals of uplink.Using these two selected transmit beams,signals encoded by STBC are transmitted to achieve diversity gain and beamforming gain at the same time,and increase the signal to noise ratio (SNR) of downlink.With simple computation and fast convergence performance,the proposed scheme is applicable for time division multiple access (TDMA) wireless communication operated in a complex interference environment.Simulation results show that the proposed scheme has better performance than conventional STBC,and can obtain a gain of about 5 dB when the bit error ratio (BER) is 10-4. 展开更多
关键词 space-time coding GAIN adaptive beamforming cyclostationary signal transmit diversity
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Research on High-Accuracy Programmable Timer Used in Acquiring UWB Signals 被引量:1
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作者 苏红旗 杨峰 +1 位作者 马凯 康文献 《Applied Geophysics》 SCIE CSCD 2005年第2期127-130,F0003,共5页
UWB signal digitization depends, to a large extent, on the accuracy of sampling time. A highaccuracy programmable timer is therefore the key to implementing UWB signal data acquisition. A high-accuracy programmable ti... UWB signal digitization depends, to a large extent, on the accuracy of sampling time. A highaccuracy programmable timer is therefore the key to implementing UWB signal data acquisition. A high-accuracy programmable timer based on the principle of ramp generators is described in this paper. The counting range of the timer is up to 16 bits, the timing precision is 8 ps, and the equivalent sampling rate is up to 50G Hz. No other identical product has been reported so far. This timer was successfully used in the data acquisition system for geological radar signals developed by us. 展开更多
关键词 high-accuracy timing UWB signal data acquisition and ramp generator
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More efficient ground truth ROI image coding technique: implementation and wavelet based application analysis 被引量:5
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作者 KUMARAYAPA Ajith 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第6期835-840,共6页
In this paper, more efficient, low-complexity and reliable region of interest (ROI) image codec for compressing smooth low texture remote sensing images is proposed. We explore the efficiency of the modified RO! cod... In this paper, more efficient, low-complexity and reliable region of interest (ROI) image codec for compressing smooth low texture remote sensing images is proposed. We explore the efficiency of the modified RO! codec with respect to the selected set of convenient wavelet filters, which is a novel method. Such ROI coding experiment analysis representing low bit rate lossy to high quality lossless reconstruction with timing analysis is useful for improving remote sensing ground truth surveillance efficiency in terms of time and quality. The subjective [i.e. fair, five observer (HVS) evaluations using enhanced 3D picture view Hyper memory display technology] and the objective results revealed that for faster ground truth ROI coding applications, the Symlet-4 adaptation performs better than Biorthogonal 4.4 and Biorthogonal 6.8. However, the discrete Meyer wavelet adaptation is the best solution for delayed ROI image reconstructions. 展开更多
关键词 Smooth low texture remote sensing (SLTRS) image Modified region of interest (ROI) image codec Wavelet filters Low bit rate (LBR). High bit rate (HBR). ROI coding
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Mean shift based log-Gabor wavelet image coding 被引量:2
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作者 LI Ji-liang FANG Xiang-zhong HOU Jun 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第4期620-624,共5页
In this paper, we propose a sparse overcomplete image approximation method based on the ideas of overcomplete log-Gabor wavelet, mean shift and energy concentration. The proposed approximation method selects the neces... In this paper, we propose a sparse overcomplete image approximation method based on the ideas of overcomplete log-Gabor wavelet, mean shift and energy concentration. The proposed approximation method selects the necessary wavelet coefficients with a mean shift based algorithm, and concentrates energy on the selected coefficients. It can sparsely approximate the original image, and converges faster than the existing local competition based method. Then, we propose a new compression scheme based on the above approximation method. The scheme has compression performance similar to JPEG 2000. The images decoded with the proposed compression scheme appear more pleasant to the human eyes than those with JPEG 2000. 展开更多
关键词 Sparse approximation LOG-GABOR Image coding Mean shift Overcomolete
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Using the Wavelet as the Private Key for Encrypting the Watermark
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作者 何小帆 《Journal of Chongqing University》 CAS 2002年第1期16-20,共5页
Watermarking is an effective approach to the copyright protection of digital media such as audio, image, and video. By inspiration from cryptography and considering the immensity of the set of all possible wavelets, i... Watermarking is an effective approach to the copyright protection of digital media such as audio, image, and video. By inspiration from cryptography and considering the immensity of the set of all possible wavelets, it is presented that in wavelet domain watermarking, the associated wavelet can be considered as the private key for encrypting the watermark so as to enhance the security of the embedded mark. This idea is partly supported by the fact that from computational complexity viewpoint, it is very time-consuming to search over the immense set of all candidate wavelets for the right one if no a priori knowledge is known about it. To verify our proposal, the standard image 'Lena' is first watermarked in a specific wavelet domain, the watermark recovery experiments are then conducted in the wavelet domain for a set of wavelets with the one used for mark embedded in it,separately. It follows from the experimental results that the mark can be recovered only in the right wavelet domain, which justifies the suggestion. 展开更多
关键词 Digital watermark WATERMARKING CRYPTOGRAPHY Private key cryptographic system WAVELET Daubechies wavelet
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Sparse constrained encoding multi-source full waveform inversion method based on K-SVD dictionary learning 被引量:1
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作者 Guo Yun-dong Huang Jian-Ping +3 位作者 Cui Chao LI Zhen-Chun LI Qing-Yang Wei Wei 《Applied Geophysics》 SCIE CSCD 2020年第1期111-123,169,共14页
Full waveform inversion(FWI)is an extremely important velocity-model-building method.However,it involves a large amount of calculation,which hindsers its practical application.The multi-source technology can reduce th... Full waveform inversion(FWI)is an extremely important velocity-model-building method.However,it involves a large amount of calculation,which hindsers its practical application.The multi-source technology can reduce the number of forward modeling shots during the inversion process,thereby improving the efficiency.However,it introduces crossnoise problems.In this paper,we propose a sparse constrained encoding multi-source FWI method based on K-SVD dictionary learning.The phase encoding technology is introduced to reduce crosstalk noise,whereas the K-SVD dictionary learning method is used to obtain the basis of the transformation according to the characteristics of the inversion results.The multiscale inversion method is adopted to further enhance the stability of FWI.Finally,the synthetic subsag model and the Marmousi model are set to test the effectiveness of the newly proposed method.Analysis of the results suggest the following:(1)The new method can effectively reduce the computational complexity of FWI while ensuring inversion accuracy and stability;(2)The proposed method can be combined with the time-domain multi-scale FWI strategy flexibly to further avoid the local minimum and to improve the stability of inversion,which is of significant importance for the inversion of the complex model. 展开更多
关键词 K-SVD dictionary sparsity constraint polarity encoding MULTI-SOURCE full waveform inversion
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Simple optical decryption based on a modified joint transform correlator technique
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作者 王怀彬 王天佐 袁晓聪 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第2期203-205,共3页
A new encryption/decryption system for optical information security is proposed in this paper. We used an iterative Fourier transform algorithm to optimize the encrypted hologram as well as the decryption key as phase... A new encryption/decryption system for optical information security is proposed in this paper. We used an iterative Fourier transform algorithm to optimize the encrypted hologram as well as the decryption key as phase-only elements. The optical decryption was implemented by superimposing the encrypted hologram and the decryyption key in a simple optical setup. Numerical simulation and optical experiment have confirmed the proposed technique as a simple and easy implementation for optical decryption, demonstrating potential applications in optical information security verification. 展开更多
关键词 computer generated holograms CORRELATOR ENCRYPTION/DECRYPTION
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SPATIALLY SCALABLE RESOLUTION IMAGE CODING METHOD WITH MEMORY OPTIMIZATION BASED ON WAVELET TRANSFORM
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作者 WangNa ZhangLi +2 位作者 ZhouXiao'an JiaChuanying LiXia 《Journal of Electronics(China)》 2005年第1期94-97,共4页
This letter exploits fundamental characteristics of a wavelet transform image to form a progressive octave-based spatial resolution. Each wavelet subband is coded based on zeroblock and quardtree partitioning ordering... This letter exploits fundamental characteristics of a wavelet transform image to form a progressive octave-based spatial resolution. Each wavelet subband is coded based on zeroblock and quardtree partitioning ordering scheme with memory optimization technique. The method proposed in this letter is of low complexity and efficient for Internet plug-in software. 展开更多
关键词 Memory optimization Spatially resolution scalability Wavelet transform Quard-tree partitioning
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Blind and readable image watermarking using wavelet tree quantization
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作者 HUYuping YUShengsheng ZHOUJingLi SHILei 《Journal of Chongqing University》 CAS 2004年第1期34-38,共5页
A blind and readable image watermarking scheme using wavelet tree quantization is proposed. In order to increase the algorithm robustness and ensure the watermark integrity,error correction coding techniques are used ... A blind and readable image watermarking scheme using wavelet tree quantization is proposed. In order to increase the algorithm robustness and ensure the watermark integrity,error correction coding techniques are used to encode the embedded watermark. In the watermark embedding process, the wavelet coefficients of the host image are grouped into wavelet trees and each watermark bit is embedded by using two trees. The trees are so quantized that they exhibit a large enough statistical difference, which will later be used for watermark extraction. The experimental results show that the proposed algorithm is effective and robust to common image processing operations and some geometric operations such as JPEG compression, JPEG2000 compression, filtering, Gaussian noise attack, and row-column removal. It is demonstrated that the proposed technique is practical. 展开更多
关键词 readable image watermrk error correction code wavelet transform QUANTIZATION
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A Novel High Spectral Efficiency Waveform Coding-OVFDM 被引量:2
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作者 LI Daoben 《China Communications》 SCIE CSCD 2015年第2期61-73,共13页
Based on the Overlapped Multiplexing Principle[12],a frequency domain OVFDM(Overlapped Frequency Domain Multiplexing) Coding is proposed.By the data weighted shift overlapped version of any band-limited Multiplexing T... Based on the Overlapped Multiplexing Principle[12],a frequency domain OVFDM(Overlapped Frequency Domain Multiplexing) Coding is proposed.By the data weighted shift overlapped version of any band-limited Multiplexing Transfer Function H(f) the coding gain and spectral efficiency are both achieved.The heavier the overlap of the data weighted Multiplexing Transfer Function H(f),the higher the coding gain and spectral efficiency as well as the closer the output to the optimum complex Gaussian distribution.The bit error probability performance is estimated.The time domain OVTDM(Overlapped Time Domain Multiplexing) Coding,the dual of OVFDM in time domain is incidentally proposed as well.Both theoretical analysis and testified simulations show that OVFDM(OVTDM) is suitable for high spectral efficiency application and its spectral efficiency is only roughly linear to SNR rather than the well-known logarithm to SNR. 展开更多
关键词 overlapped multiplexing principle frequency domain coding waveform coding spectral efficiency shannon capacity dual relation OVFDM OVTDM
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Statistical Analysis on the Corner Period of Site-Related Design Spectra
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作者 WuJian GaoMengtan 《Earthquake Research in China》 2005年第1期29-34,共6页
According to the results of site seismic hazard analysis accomplished in the past decades, 96 site-related design spectra are selected as samples in this study. The result shows that the value of the corner period (T ... According to the results of site seismic hazard analysis accomplished in the past decades, 96 site-related design spectra are selected as samples in this study. The result shows that the value of the corner period (T g) of the design spectrum in GBJ11-89 (China Seismic Building Code, issued in 1989) is lower than the value obtained by site seismic hazard analysis. The same situation exists when we compare the design spectra of the Codes to the spectra according to the earthquake records. The value in current seismic design code, GBJ50011-2001 issued in 2001, is greater than that in GBJ11-89, but still less than the value obtained by site seismic hazard analysis. If we accept the value got by site seismic hazard analysis, we have a suspicion that 2/3 of buildings built according to GBJ11-89 will not be safe when an earthquake with 2% probability of exceedance in 50 years occurs. 展开更多
关键词 Site-related design spectrum Corner period of design spectrum Seismic code
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WAVELET-BASED FINE GRANULARITY SCALABLE VIDEO CODING
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作者 Zhang Jiangshan Zhu Guangxi (Dept. of Electronics & Info. Eng., Huazhong University of Science & Technology, Wulian 430074) 《Journal of Electronics(China)》 2003年第1期38-44,共7页
This letter proposes an efficient wavelet-based Fine Granularity Scalable (FGS)coding scheme, where the base layer is encoded with a newly designed wavelet-based coder, and the enhancement layer is encoded with Progre... This letter proposes an efficient wavelet-based Fine Granularity Scalable (FGS)coding scheme, where the base layer is encoded with a newly designed wavelet-based coder, and the enhancement layer is encoded with Progressive Fine Granularity Scalable (PFGS) coding.This algorithm involves multi-frame motion compensation, rate-distortion optimizing strategy with Lagrangian cost function and context-based adaptive arithmetic coding. In order to improve efficiency of the enhancement layer coding, an improved motion estimation scheme that uses both information from the base layer and the enhancement layer is also proposed in this letter. The wavelet-based coder significantly improves the coding efficiency of the base layer compared with MPEG-4 ASP (Advanced Simple Profile) and H.26L TML9. The PFGS coding is a significant improvement over MPEG-4 FGS coding at the enhancement layer. Experiments show that single layer coding efficiency gain of the proposed scheme is about 2.0-3.0dB and 0.3-1.0dB higher than that of MPEG-4 ASP and H.26L TML9, respectively. The overall coding efficiency gain of the proposed scheme is about 4.0-5.0dB higher than that of MPEG-4 FGS. 展开更多
关键词 Wavelet-based coding Scalable coding FGS coding H.26L MPEG-4
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MULTI-RESOLUTION MOTION ESTIMATION AND COMPENSATION BASED ON ADJACENT PREDICTION OF FRAME DIFFERENCE IN WAVELET DOMAIN 被引量:3
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作者 Tang Guowei Gu Guochang 《Journal of Electronics(China)》 2009年第3期412-416,共5页
Aiming at the higher bit-rate occupation of motion vector encoding and more time load of full-searching strategies, a multi-resolution motion estimation and compensation algorithm based on adjacent prediction of frame... Aiming at the higher bit-rate occupation of motion vector encoding and more time load of full-searching strategies, a multi-resolution motion estimation and compensation algorithm based on adjacent prediction of frame difference was proposed.Differential motion detection was employed to image sequences and proper threshold was adopted to identify the connected region.Then the motion region was extracted to carry out motion estimation and motion compensation on it.The experiment results show that the encoding efficiency of motion vector is promoted, the complexity of motion estimation is reduced and the quality of the reconstruction image at the same bit-rate as Multi-Resolution Motion Estimation(MRME) is improved. 展开更多
关键词 Wavelet transforms Motion estimation Motion compensation Multi-resolution analysis Video coding
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The Dates of the Reign of Vakhtang Gorgasali
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作者 Manana Sanadze 《History Research》 2013年第5期370-375,共6页
Georgian historiography dates the reign of King Vakhtang Gorgasali (Gorg-a-sar--'wolf-head' in Persian) to the 2nd half of 5th century. The king is considered to have died in 502 in a fight with Persians. Cyril To... Georgian historiography dates the reign of King Vakhtang Gorgasali (Gorg-a-sar--'wolf-head' in Persian) to the 2nd half of 5th century. The king is considered to have died in 502 in a fight with Persians. Cyril Toumanoff has expressed an opinion about the identification of Vakhtang Gorgasali with the King of Kartli Gurgen, mentioned by Procopius of Caesarea in 523. Accordingly, he believed that in case of such an identification, Vakhtang Gorgasali should have died in 527 during the big Persian invasion of Georgia. We have noticed that the author of the martyrdom of David and Constantine, who were based on the ancient chronicle ("Dzveli Utskebani"---Old Story) and who created his hagiographic work in the middle of 1 lth century, made a big mistake: erroneously, due to the similarity of names, he identified the sons of Georgian King Vakhtang Gorgasali Darchil and Mihrdat and the invasion of Persians in their reign with the sons of the ruler of Georgia (Kartli) Stephanoz III Mihrdat and Archil and invasions of Arabs and Marwan ibn Muhammad (Murvan Qru--"Marwan the Deaf') that took place two centuries later, in the 30s of 8th century. Consequently, the author related the martyrdom on the background of Arab invasions. The fact that according to the author of the martyrdom, the sons of Vakhtang Gorgasali were in West Georgia, namely Anakopia, and fought the so-called Arabs there, makes it clear that the historical developments were taking place in the period of the Great Persian-Byzantine War of 542-562. In the title of the work it is mentioned that the invasion, during which the martyrdom of David and Constantine took place, happened in the vicinity of the death of Vakhtang Gorgasali. Thus, it becomes clear that King Vakhtang Gorgasali could not have died during the Persian-Byzantine War of 502-505 and that the Great Invasion of Persians described in the "Georgian Chronicles", in which Vakhtang Gorgasali was wounded, could only have happened in 527. The king must have died during a war between Persia and Byzantium in 527-532, more specifically in 527 when Persians invaded Georgia. Proceeding from the above, the surmise of Cyril Toumanoff regarding the death of Vakhtang Gorgasali in 527 becomes more convincing and well-grounded. Since it is known that King Vakhtang Gorgasali lived 60 years, the date of his birth can be presumed to be 466-467. This gives us an opportunity to establish a more precise date of reign ofVakhtang's father-Mihrdat and his grandfather-Archil. The dates of reign we have put forward for kings Mihrdat and Archil (Archil ,130-463, Mihrdat--463-473) correspond to the information of the Assyrian version of the Life of Peter the Iberian. 展开更多
关键词 Vakhtang Gorgasali Kings of Georgia IV-VI cc Georgian Chronicles Aspagur (Varaz-Bakur) PeterIberian Gurgen the King of Iberia King of Kartli Mihrdat King Darchil
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THE PHASE-OFFSET OVERLAPPED WAVE TECHNIQUE 被引量:3
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作者 Liang Dequn (Dalian Maritime University, Dalian 116026)Liang Weihua (Dalian University of Science and Technology, Dalian 116026)Sun Changnian (Telecom Sino Group, Sunnyvale, California, USA, 94086) 《Journal of Electronics(China)》 2003年第2期121-127,共7页
A new digital communication technology based on the Phase-Offset Overlapped Waves (POOW) has been introduced in this letter. The waves can be considered as a special multicarrier different from traditional ones. The s... A new digital communication technology based on the Phase-Offset Overlapped Waves (POOW) has been introduced in this letter. The waves can be considered as a special multicarrier different from traditional ones. The sub-waves in a coded word's period of the POOW are sine waves and have the same frequencies, but different starting phases. The most important characteristic is that these sub-waves are the piecewise functions and not orthogonal in a code word period. The decoding can be implemented by solving a linear equation group. This code has very high efficiency and thus the data transmission rate is increased greatly. 展开更多
关键词 Digital communications CODING MULTICARRIER Phase-offset overlapped wave
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