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Improved side information generation algorithm for Wyner-Ziv video coding

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The Journal of China Universities of Posts and Telecommunications 2014年第1期21卷 109-115页

作者： zhang deng-yin WU Yuan-yuan WAN Ming-xiang Sci-Tech Park of Internet of Things Nanjing University of Posts and Telecommunication Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunication

Side information has a significant influence on the rate-distortion（RD） performance of distributed video coding（DVC）. In the conventional motion compensated frame interpolation scheme, all blocks adopt the same side-information generation method regardless of the motion intensity inequality at different regions. In this paper, an improved method is proposed. The image blocks are classified into two modes, fast motion and slow motion, by simply computing the discrete cosine transformation（DCT） coefficients at the encoder. On the decoder, it chooses the direct interpolation and refined motion compensated interpolation correspondingly to generate side information. Experimental results show that the proposed method, without increasing the encoder complexity, can increase the average peak signal-to-noise ratio（PSNR） by up to 1~ 2 dB compared with the existing algorithm. Meanwhile, the proposed algorithm significantly improves the subjective quality of the side information.

关键词： DVC side information motion estimation motion compensation

Design and implementation of improved watermarking system in WT domain

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 58-63页

作者： zhang deng-yin CHEN Jia-ping SUN Jun-cai Institute of Digital Processing and Transmission Nanjing University of Posts s Nanjing 210003 China

This article presents a watermarking algorithm based on one-dimensional （1-D） chaotic map in wavelet transform （WT） domain. Traditional encryption and watermarking technologies in the WT domain are combined in this algorithm. First, the watermark is encoded by a chaotic sequence, which is generated by a key. On the basis of human visual system （HVS）, it is then divided into two parts and embedded into the low- and intermediate-frequency bands of three-layer WT domain. The encryption of the watermark and the choice of embedded areas based on the perceptivity not only confer the watermark with good invisibility but also with good robustness. Meanwhile, it is difficult to decrypt the watermark extracted from the WT domain.

关键词： watermarking chaotic map WT invisibility robustness

QoS-guaranteed packet scheduling in wireless networks

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 63-67页

作者： zhang deng-yin JIANG Juan ANANI Adi LI Hai-bo Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China Department of Applied Physics and Electronics Umea University Umea 90187 Sweden

To guarantee the quality of service （QoS） of a wireless network, a new packet scheduling algorithm using cross-layer design technique is proposed in this article. First, the demand of packet scheduling for multimedia transmission in wireless networks and the deficiency of the existing packet scheduling algorithms are analyzed. Then the model of the QoS-gnaranteed packet scheduling （QPS） algorithm of high speed downlink packet access （HSDPA） and the cost function of packet transmission are designed. The calculation method of packet delay time for wireless channels is expounded in detail, and complete steps to realize the QPS algorithm are also given. The simulation results show that the QPS algorithm that provides the scheduling sequence of packets with calculated values can effectively improve the performance of delay and throughput.

关键词： packet scheduling QoS wireless network cross-layer design

Functional assessment of cadherin as a shared mechanism for cross/dual resistance to Cry1Ac and Cry2Ab in Helicoverpa zea

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Journal of Integrative Agriculture 2024年第5期23卷 1604-1617页

作者： Jizhen Wei Min zhang Pin Li Zhongyuan deng Xinming yin Shiheng An Xianchun Li State Key Laboratory of Wheat and Maize Crop Science/College of Plant Protection Henan Agricultural UniversityZhengzhou 450046China Department of Entomology and BIO5 Institute University of ArizonaTucsonAZ 85721USA School of Agricultural Sciences Zhengzhou UniversityZhengzhou 450001China

Helicoverpa zea is a major target pest of pyramided transgenic crops expressing Cry1,Cry2 and/or Vip3Aa proteins from Bacillus thuringiensis(Bt)in the United ***-selected Cry1Ac/Cry2Ab cross resistance and fieldevolved practical dual resistance of *** to these two toxins have been widely *** the widespread Cry1Ac/Cy2Ab dual resistance of *** has resulted from the selection of one shared or two independent resistance mechanisms by pyramided Bt crops remains *** is a well-confirmed receptor of Cry1Ac and a suggested receptor of Cry2Ab in at least three Lepidopteran *** test whether cadherin may serve as one shared mechanism for the cross and dual resistance of *** to Cry1Ac and Cry2Ab,we cloned *** cadherin(HzCadherin)cDNA and studied its functional roles in the mode of action of Cry1Ac and Cry2Ab by gain-and lossof-function *** expression of HzCadherin in *** midgut,*** fat body and Sf9 cells made all three of these cell lines more susceptible to activated Cry1Ac but not activated Cry2Ab,whereas silencing HzCadherin of *** midgut and fat body cells significantly reduced the susceptibility to Cry1Ac but not ***,suppressing HzCadherin with siRNA made *** larvae resistant to *** results clearly demonstrate that HzCadherin is not a receptor for Cry2Ab,and thus it is unlikely to serve as one shared mechanism for the cross and dual resistance of *** to Cry1Ac and Cry2Ab.

关键词： Bt crops cadherin Cry toxin receptor resistance mechanism

M-learning in review： Technology, standard and evaluation

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通讯和计算机（中英文版） 2008年第11期5卷 1-6页

作者： ANANI Adi zhang deng-yin LI Hai-bo Digital Media Laboratory Department of Applied Physics and Electronics Umea University Umea 90187 Sweden Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China

Nowadays E-learning as a form of learning depending on networks and computer devices has been expanding by leaps and bounds. As a special kind of E-learning, M-learning (mobile learning) aims at the use of mobile devices anywhere at anytime by anybody. In this paper, the technologies to develop a M-learning system are deeply analyzed according to the layer model at first. Then, from the view of application, the standardization in M-learning is researched in order to accelerate the development and popularization of M-learning. Finally, quality estimation of M-learning system is discussed from the view of QoE (quality of experiences). The experience form end-user is the sole effective norm to judge the result of M-learning technology. It is no doubt that technologies, standardization and evaluation will play very important parts in the course of M-learning development.

关键词：电子学习移动设备移动学习系统技术创新

New structure transistors for advanced technology node CMOS ICs

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National Science Review 2024年第3期11卷 24-41页

作者： Qingzhu zhang Yongkui zhang Yanna Luo Huaxiang yin Integrated Circuit Advanced Process R&D Center Institute of Microelectronics of Chinese Academy of Sciences(IMECAS) State key Lab of Fabrication Technologies for Integrated Circuits Institute of Microelectronics of Chinese Academy of Sciences School of Integrated Circuits University of Chinese Academy of Sciences

Over recent decades, advancements in complementary metal-oxide-semiconductor integrated circuits(ICs)have mainly relied on structural innovations in transistors. From planar transistors to the fin field-effect transistor(FinFET) and gate-all-around FET(GAAFET), more gate electrodes have been added to three-dimensional(3D) channels with enhanced control and carrier conductance to provide higher electrostatic integrity and higher operating currents within the same device footprint. Beyond the 1-nm node, Moore's law scaling is no longer expected to be applicable to geometrical shrinkage. Vertical transistor stacking, e.g. in complementary FETs(CFET), 3D stack(3DS) FETs and vertical-channel transistors(VFET), for enhanced density and variable circuit or system design represents a revolutionary scaling approach for sustained IC development. Herein, innovative works on specific structures, key process breakthroughs, shrinking cell sizes and design methodologies for transistor structure research and development are reviewed. Perspectives on future innovations in advanced transistors with new channel materials and operating theories are also discussed.

关键词： transistor CMOS GAAFET CFET 3DS FET

Nutrient transport following water transfer through the world's largest water diversion channel

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Journal of Environmental Sciences 2024年第1期135卷 703-714页

作者： Yuanhui Cheng Hong zhang Wei yin State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085 China Changjiang Water Resources Protection Institute Wuhan 430051China University of Chinese Academy of Sciences Beijing 100049China

Nutrient levels in the artificial channel constructed for the Middle Route Project are significant indicators of water quality safety and aquatic ecological integrity for this large,interbasin ***,the distribution and transport of nutrients along the channel were poorly *** on a time-series dataset as well as mass balance and material flow analysis methods,the water and nutrient transport fluxes in the Middle Route of the South-to-North Water Diversion Project were identified in this *** results indicate that the nutrient concentrations varied considerably with time,but there was no significant difference among the 30 stations of the main *** temperature difference was the major factor in the large fluctuations of water quality indicators over *** nutrient loadings varied with the water volume outputs from the main channel to the waterreceiving *** deposition was an important source of nutrients in the main channel,accounting for 9.13%,20.6%,and 0.635%of the nitrogen,phosphorus,and sulfur input from the Danjiangkou Reservoir,*** 2021,a net accumulation of 988 tons of N,29 tons of P,and 2,540 tons of S,respectively,were present in the main *** increase of these external and internal nutrient loadings would cause water quality fluctuation and deterioration in some local sections of the main *** study quantified the spatial and temporal patterns of nutrient transport in the Middle Route and revealed the ecological effects on the aquatic environment,assisting authorities on the project to develop effective water conservation strategies.

关键词： Nutrient transport Spatiotemporal patterns The Middle Route The South-to-North Diversion Project Hydro-ecological effects Water-receiving cities

Simulation of MC-CDMA in the Presence of Timing Errors

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The Journal of China Universities of Posts and Telecommunications 2002年第2期9卷 7-12页

作者： zhang deng yin, ZHENG Bao yu (Nanjing University of Posts and Telecommunications, Nanjing 210003, P.R.China) Nanjing University of Posts and Telecommunications Nanjing 210003 P.R.China

In this paper, new multiple access schemes based on thecombination of Code Division Multiple Access (CDMA)andMulticarrier(MC)modulation(also known as OFDM)are reviewed. Adescription of a simulation platform developed to analyse theperformance of such systems in the presence of timing errors isincluded. It is shown that the MC-CDMA system is very sensitive to aclock frequency offset, and the system performance rapidly de- gradesfor an increasing number of carriers. It is also shown that thetiming jitter gives rise to a performance degra- dation that isessentially independent of the number of carriers.

关键词： MC modulation CDMA simulation

Performance Analysis of MC-CDMA in the Presence of Carriers Phase Errors

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The Journal of China Universities of Posts and Telecommunications 2002年第3期9卷 17-22页

作者： zhang deng yin, ZHENG Bao yu (Nanjing University of Posts and Telecommunications, Nanjing 210003, P.R.China) Nanjing University of Posts and Telecommunications Nanjing 210003 P.R.China

This paper presents the effect of carriers phase error on MC-CDMA performancein downlink mobile communications. Signal-to-Noise Ratio (SNR) and Bit-Error-Rate (BER) areanalyzed taking into account the effect of carrier phase errors . It is shown that the MC-CDMAsystem is very sensitive to a carrier frequency offset, the system performance rapidly degrades andstrongly depends on the number of carriers. For a maximal load, the degradation caused by carrierphase jitter is independent of the number of the carriers.

关键词： MC-CDMA carrier phase simulation