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| 1 | Coding metamaterials, digital metamaterials and programmable metamaterials显示文摘Metamaterials are artificial structures that are usually described by effective medium parameters on the macroscopic scale,and these metamaterials are referred to as‘analog metamaterials’.Here,we propose‘digital metamaterials’through two steps.First,we present‘coding metamaterials’that are composed of only two types of unit cells,with 0 and p phase responses,which we name‘0’and‘1’elements,respectively.By coding‘0’and‘1’elements with controlled sequences(i.e.,1-bit coding),we can manipulate electromagnetic(EM)waves and realize different functionalities.The concept of coding metamaterials can be extended from 1-bit coding to 2-bit coding or higher.In 2-bit coding,four types of unit cells,with phase responses of 0,p/2,p,and 3p/2,are required to mimic the‘00’,‘01’,‘10’and‘11’elements,respectively.The 2-bit coding has greater freedom than 1-bit coding for controlling EM waves.Second,we propose a unique metamaterial particle that has either a‘0’or‘1’response controlled by a biased diode.Based on this particle,we present‘digital metamaterials’with unit cells that possess either a‘0’or‘1’state.Using a field-programmable gate array,we realize digital control over the digital metamaterial.By programming different coding sequences,a single digital metamaterial has the ability to manipulate EM waves in different manners,thereby realizing‘programmable metamaterials’.The above concepts and physical phenomena are confirmed through numerical simulations and experiments using metasurfaces. | Tie Jun Cui Mei Qing Qi Xiang Wan Jie Zhao Qiang Cheng | 2014 | Light(Science & Applications)2014，3，1： | 130 |
| 2 | Programmable time-domain digital-coding metasurface for non-linear harmonic manipulation and new wireless communication systems显示文摘Optical non-linear phenomena are typically observed in natural materials interacting with light at high intensities, and they benefit a diverse range of applications from communication to sensing. However,controlling harmonic conversion with high efficiency and flexibility remains a major issue in modern optical and radio-frequency systems. Here, we introduce a dynamic time-domain digital-coding metasurface that enables efficient manipulation of spectral harmonic distribution. By dynamically modulating the local phase of the surface reflectivity, we achieve accurate control of different harmonics in a highly programmable and dynamic fashion, enabling unusual responses, such as velocity illusion. As a relevant application, we propose and realize a novel architecture for wireless communication systems based on the time-domain digital-coding metasurface, which largely simplifies the architecture of modern communication systems, at the same time yielding excellent performance for real-time signal transmission. The presented work, from new concept to new system, opens new pathways in the application of metamaterials to practical technology. | Jie Zhao Xi Yang Jun Yan Dai Qiang Cheng Xiang Li Ning Hua Qi Jun Chen Ke Guo Dong Bai Shuo Liu Shi Jin Andrea Alù Tie Jun Cui | 2019 | National Science Review2019，6，2： | 46 |
| 3 | Broadband diffusion of terahertz waves by multi-bit coding metasurfaces显示文摘The terahertz region is a special region of the electromagnetic spectrum that incorporates the advantages of both microwaves and infrared light waves.In the past decade,metamaterials with effective medium parameters or gradient phases have been studied to control terahertz waves and realize functional devices.Here,we present a new approach to manipulate terahertz waves by using coding metasurfaces that are composed of digital coding elements.We propose a general coding unit based on a Minkowski closed-loop particle that is capable of generating 1-bit coding(with two phase states of 0 and 180°),2-bit coding(with four phase states of 0,90°,180°,and 270°),and multi-bit coding elements in the terahertz frequencies by using different geometric scales.We show that multi-bit coding metasurfaces have strong abilities to control terahertz waves by designing-specific coding sequences.As an application,we demonstrate a new scattering strategy of terahertz waves—broadband and wide-angle diffusion—using a 2-bit coding metasurface with a special coding design and verify it by both numerical simulations and experiments.The presented method opens a new route to reducing the scattering of terahertz waves. | Li-Hua Gao Qiang Cheng Jing Yang Shao-Jie Ma Jie Zhao Shuo Liu Hai-Bing Chen Qiong He Wei-Xiang Jiang Hui-Feng Ma Qi-Ye Wen Lan-Ju Liang Biao-Bing Jin Wei-Wei Liu Lei Zhou Jian-Quan Yao Pei-Heng Wu Tie-Jun Cui | 2015 | Light(Science & Applications)2015，4，1： | 31 |
| 4 | Construction of infectious cDNA clones of PRRSV:Separation of coding regions for nonstructural and structural proteins显示文摘Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), the causative agent of the ongoing 'porcine high fever syndrome' in China, is capable of genetic and antigenic mutations at high fre- quency. How to design vaccine rationally to keep up with the ever-changing prevalent PRRSV variant is of great interest. We developed an infectious cDNA clone of an attenuated strain of Type II PRRSV, and further manipulated the infectious cDNA clone by inserting polylinker between ORF1 and ORF2, en- coding for nonstructural- or structural-protein, respectively. The cDNA was generated from the cell-attenuated virus strain, APRRS, via RT-PCR, and followed by nucleotide sequencing and molecular cloning. The full-length of the APRRS genomic RNA was determined as 15521 nucleotides in length excluding poly(A) tail, which has a 99.7% nucleotide identity with that of PRRSV Nsp strain, also a vac- cine strain. Based on the nucleotide sequencing results, the full-length cDNA clone was assembled in pBlueScript vector, under the control of T7 promoter at the immediate 5′ terminus of genome. To dis- cern the rescued viruses from that of parental virus, a Mlu I restriction site was engineered into ORF5 coding region. Upon transfection of the in vitro transcripts of both the original and Mlu I-tagged cDNAs into MA-104 cells, typical PRRSV cytopathic effects were observed. The rescued viruses from the full-length cDNA clones displayed the same virological and molecular properties. Subsequently, PCR-based mutagenesis was conducted to separate the coding regions between PRRSV nonstructural genes, ORF1, and structural proteins, ORF2-ORF7. The synthetic RNA of such mutant clone, pCSA, was infectious and the rescued virus shared similar properties with that of the parental virus. This study provided a valuable tool for development of chimeric PRRSV as vaccine candidate offering cross-protection to various genetically diversified PRRSV strains, and a platform for further develop- ment of PRRSV as a gene expression vector for recombinant vaccines against other significant swine diseases. | YUAN ShiShan & WEI ZuZhang Department of Animal Infectious Diseases, Key Laboratory of Animal Parasitology Chinese Ministry of Agriculture, Shanghai Vet- erinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200232, China | 2008 | Science China(Life Sciences)2008，51，3： | 19 |
| 5 | Deadline-aware network coding for video on demand service over P2P networks显示文摘We are interested in providing Video-on-Demand (VoD) streaming service to a large population of clients using peer-to-peer (P2P) approach. Given the asynchronous demands from multiple clients, continuously changing of the buffered contents, and the continuous video display requirement, how to collaborate with potential partners to get expected data for future content delivery are very important and challenging. In this paper, we develop a novel scheduling algorithm based on deadline- aware network coding (DNC) to fully exploit the network resource for efficient VoD service. DNC generalizes the existing net- work coding (NC) paradigm, an elegant solution for ubiquitous data distribution. Yet, with deadline awareness, DNC improves the network throughput and meanwhile avoid missing the play deadline in high probability, which is a major deficiency of the con- ventional NC. Extensive simulation results demonstrated that DNC achieves high streaming continuity even in tight network conditions. | CHI Hui-cheng ZHANG Qian | 2006 | Journal of Zhejiang University-Science A(Applied Physics & Engineering)2006，7，5： | 13 |
| 6 | An Approach of Steganography in G.729 Bitstream Based on Matrix Coding and Interleaving显示文摘This paper proposes an approach of secure communication through the Internet based on the technology of speech information hiding. In this approach,the algorithm of embedding a 2.4Kbps low-bit-rate Mixexcitation linear prediction(MELP) speech into G.729 coding speech is presented by adapting the techniques of covering code and the interleaving. The parameters in G.729 source codec are analyzed in the Capability of noise tolerance(CNT) and selected to carry secret speech data because these parameters have less impact on the quality of being reconstructed speech. Experiment results show that the proposed steganography algorithm not only gained a high data embedding rate up to 2.4Kbps but also achieved better imperceptibility, which indicates that the algorithm can be used for high data embedding capacity hiding and can achieve good effect. | WU Zhijun CAO Haijuan LI Douzhe | 2015 | Chinese Journal of Electronics2015，24，1： | 9 |
| 7 | New chaotical image encryption algorithm based on Fisher–Yatess scrambling and DNA coding显示文摘Based on the Fisher–Yatess scrambling and DNA coding technology, a chaotical image encryption method is proposed. First, the SHA-3 algorithm is used to calculate the hash value of the initial password, which is used as the initial value of the chaotic system. Second, the chaotic sequence and Fisher–Yatess scrambling are used to scramble the plaintext,and a sorting scrambling algorithm is used for secondary scrambling. Then, the chaotic sequence and DNA coding rules are used to change the plaintext pixel values, which makes the ciphertext more random and resistant to attacks, and thus ensures that the encrypted ciphertext is more secure. Finally, we add plaintext statistics for pixel-level diffusion to ensure plaintext sensitivity. The experimental results and security analysis show that the new algorithm has a good encryption effect and speed, and can also resist common attacks. | 王兴元 张钧荐 张付臣 曹光辉 | 2019 | Chinese Physics B2019，28，4： | 8 |
| 8 | Physical Layer Security with Its Applications in 5GNetworks: A Review显示文摘5G network is expected to support massive user connections and exponentially increasing wireless services,which makes network security unprecedentedly important.Unlike traditional security-guaranteeing techniques which rely heavily on cryptographic approaches at upper layers of the protocol stack,physical-layer security(PLS) solutions fully take advantages of the characteristics of wireless channels to degrade the received signal qualities at the malicious users,and realize keyless secure transmission via signal design and signal processing techniques.PLS avoids the difficulties in the distribution and management of secret keys,and provides flexible security levels through adaptive transmission protocol design.Moreover,PLS techniques match the features of 5G networks well.Therefore,the application of PLS to 5G networks is a promising solution to address the security threats.This article presents a comprehensive review of the state-of-the-art PLS techniques,and discusses their applications in 5G networks.We first summarize the principle and advantages of PLS techniques,and point out the reasons why PLS is suitable for 5G networks.Then,we review the existing PLS methods in literature,and highlight severalPLS solutions that are expected to be applied in 5G networks.Finally,we conclude this article and figure out some further research directions. | Li Sun Qinghe Du | 2017 | China Communications2017，14，12： | 7 |
| 9 | RTP payload format for H.264/SVC scalable video coding显示文摘The scalable extension of H.264/AVC, known as scalable video coding or SVC, is currently the main focus of the Joint Video Team’s work. In its present working draft, the higher level syntax of SVC follows the design principles of H.264/AVC. Self-contained network abstraction layer units (NAL units) form natural entities for packetization. The SVC specification is by no means finalized yet, but nevertheless the work towards an optimized RTP payload format has already started. RFC 3984, the RTP payload specification for H.264/AVC has been taken as a starting point, but it became quickly clear that the scalable features of SVC require adaptation in at least the areas of capability/operation point signaling and documentation of the extended NAL unit header. This paper first gives an overview of the history of scalable video coding, and then reviews the video coding layer (VCL) and NAL of the latest SVC draft specification. Finally, it discusses different aspects of the draft SVC RTP payload format, in- cluding the design criteria, use cases, signaling and payload structure. | WENGER Stephan HANNUKSELA Miska M. | 2006 | Journal of Zhejiang University-Science A(Applied Physics & Engineering)2006，7，5： | 7 |
| 10 | Microwave metamaterials: from exotic physics to novel information systems显示文摘Metamaterials and metasurfaces have attracted much attention due to their powerful ability to control electromagnetic(EM)waves.In this paper,we review the recent developments in the field of EM metamaterials,starting from their exotic physics to their applications in novel information systems.First,we show the fundamental understanding on traditional metamaterials based on the effective medium theory and related applications,such as invisibility cloaks and meta-lenses.Second,we review the two-dimensional versions of metamaterials,i.e.,metasurfaces,for controlling spatial waves and surface waves and thereafter present their typical designs.In particular,we briefly introduce spoof surface plasmon polaritons and their applications in microwave frequencies.Following the above approach,we emphatically present the concepts of digital coding metamaterials,programmable metamaterials,and information metamaterials.By extending the principles of information science to metamaterial designs,several functional devices and information systems are presented,which enable digital and EM-wave manipulations simultaneously.Finally,we give a brief summary of the development prospects for microwave metamaterials. | Rui-yuan WU Tie-jun CUI | 2020 | Frontiers of Information Technology & Electronic Engineering2020，21，1： | 7 |
| 11 | Feature Representation for Facial Expression Recognition Based on FACS and LBP显示文摘In expression recognition, feature representation is critical for successful recognition since it contains distinctive information of expressions. In this paper, a new approach for representing facial expression features is proposed with its objective to describe features in an effective and efficient way in order to improve the recognition performance. The method combines the facial action coding system(FACS) and 'uniform' local binary patterns(LBP) to represent facial expression features from coarse to fine. The facial feature regions are extracted by active shape models(ASM) based on FACS to obtain the gray-level texture. Then, LBP is used to represent expression features for enhancing the discriminant. A facial expression recognition system is developed based on this feature extraction method by using K nearest neighborhood(K-NN) classifier to recognize facial expressions. Finally, experiments are carried out to evaluate this feature extraction method. The significance of removing the unrelated facial regions and enhancing the discrimination ability of expression features in the recognition process is indicated by the results, in addition to its convenience. | Li Wang Rui-Feng Li Ke Wang Jian Chen | 2014 | International Journal of Automation and computing2014，11，5： | 7 |
| 12 | Load Balanced Coding Aware Multipath Routing for Wireless Mesh Networks显示文摘The growth of network coding opportunities is considered the unique optimization goal by most current network coding based routing algorithms for wireless mesh networks. This usually results in flows aggregation problem in areas with coding opportunities, and degrades the network performance. This paper proposes a Load balanced coding aware multipath routing(LCMR)for wireless mesh networks. To facilitate the evaluation of discovered multiple paths and the tradeoffs between coding opportunity and load balancing, a novel routing metric, Load balanced coding aware routing metric(LCRM) is presented, which considers the load degree of nodes when detects coding opportunities. LCMR could spread traffic over multipath to further balance load. Simulation results demonstrate that LCMR could evenly spread the traffic over the network with increasing network throughput in a heavy load at the expense of some coding opportunities. | SHAO Xing WANG Ruchuan HUANG Haiping SUN Lijuan | 2015 | Chinese Journal of Electronics2015，24，1： | 6 |
| 13 | Color Image Segmentation Based on HSI Model显示文摘ColorImageSegmentationBasedonHSIModelZhangYujin(章毓晋),YaoYurong,HeYun(DepartmentofElectronicEngineering,TsinghuaUniversity,Be... | 章毓晋 | 1998 | High Technology Letters1998，4，1： | 6 |
| 14 | Overview of the Second Generation AVS Video Coding Standard(AVS2)显示文摘AVS2 is a new generation video coding standard developed by the AVS working group. Compared with the first generation AVS video coding standard, known as AVS1, AVS2 significantly improves coding performance by using many new coding technologies,e.g., adaptive block partition and two level transform coding. Moreover, for scene video, e.g. surveillance video and conference video, AVS2 provided a background picture modeling scheme to achieve more accurate prediction, which can also make object detection and tracking in surveillance video coding more flexible. Experimental results show that AVS2 is competitive with High Efficiency Video Coding(HEVC) in terms of performance. Especially for scene video, AVS2 can achieve 39% bit rate saving over HEVC. | Shanshe Wang Falei Luo Siwei Ma | 2016 | ZTE Communications2016，14，1： | 6 |
| 15 | 多速率多播最大吞吐量问题研究显示文摘该文研究了利用network coding的多速率多播最大吞吐量问题。与以往研究重点集中在单速率多播中的network coding研究工作不同,该文考虑了链路的异构性问题并采用多速率多播来解决该问题。文中形式化地描述了多速率多播最大可得吞吐量问题,并证明了在分层独立和层速率固定条件下,利用network coding的多速率多播最大吞吐量问题是NP-hard类问题,同时给出了最大吞吐量的上界。该文同时还研究了分层相关和层速率可变情况下的最大吞吐量问题,并提出了一种满足公平性的近似算法。 | 张牧 张顺颐 刘伟彦 | 2008 | 电子与信息学报2008，30，1： | 6 |
| 16 | Long noncoding RNA in cardiac aging and disease显示文摘Cardiovascular diseases(CVDs)are the main cause of morbidity and mortality in Western society and present an important agerelated risk.With the constant rise in life expectancy,prevalence ofCVD in the population will likely increase further.New therapies,especially in the elderly,are needed to combat CVD.This review is focused on the role of long noncoding RNA(IncRNA)in CVD.RNA sequencing experiments in the past decade showed that most RNA does not code for protein,but many RNAs function as ncRNA.Here,we summarize the recent findings of IncRNA regulation in the diseased heart.The potential use of these RNAs as biomarkers of cardiac disease prediction is also discussed. | Noelia Lozano-Vidal Diewertje IBink Reinier A.Boon | 2019 | Journal of Molecular Cell Biology2019，11，10： | 5 |
| 17 | Active digital spoof plasmonics显示文摘Digital coding and digital modulation are the foundation of modern information science.The combination of digital technology with metamaterials provides a powerful scheme for spatial and temporal controls of electromagnetic waves.Such a technique,however,has thus far been limited to the control of free-space light.Its application to plasmonics to shape subwavelength fields still remains elusive.Here,we report the design and experimental realization of a tunable conformal plasmonic metasurface;which is capable of digitally coding and modulating designer surface plasmons at the deep-subwavelength scale.Based on dynamical switching between two discrete dispersion states in a controlled manner;we achieve digital modulations ofboth amplitude and phase of surface waves with nearly 100%modulation depth on a single device.Our study not only introduces a new approach for active dispersion engineering,but also constitutes an important step towards the realization of subwavelength integrated plasmonic circuits. | Hao Chi Zhang Tie Jun Cui Yu Luo Jingjing Zhang Jie Xu Pei Hang He Le Peng Zhang | 2020 | National Science Review2020，7，2： | 5 |
| 18 | H.264/AVC码率控制现状与发展显示文摘作为视频通信中非常重要的关键技术之一,码率控制用于调整视频码流以满足带宽受限的条件,能够直接影响视频编码器输出码率的稳定性和保证视频质量。首先描述码率控制问题,给出码率控制算法的分类准则;然后对众多的H.264/先进视频编码(advanced video coding,AVC)码率控制算法根据应用目的进行具体描述;最后从适用标准和应用目的两个方面,详细指出码率控制技术今后的研究方向。 | 吴炜 陈健 宋彬 | 2013 | 系统工程与电子技术2013，35，5： | 5 |
| 19 | 基于图形信息的HEVC帧间预测快速算法显示文摘由于最新的视频编码标准HEVC(high efficiency video coding)应用四叉树的递归结构进行编码单元的划分,使得帧间预测的过程极为复杂,编码的时间效率比较低下。针对HEVC帧间预测过程,提出了一种基于纹理信息和稳定区域检测的快速算法,旨在检测出相对平坦的区域和随时间变化较稳定的区域,来提前终止四叉树的编码单元的划分。这些平坦或者稳定的区域用较大的编码预测单元就能进行比较准确的运动估计和预测,不需要再进行更小编码预测单元的划分,因此HEVC编码器的时间复杂度大幅度降低。实验结果表明,改进后的算法编码时间平均节省了34%左右,并且造成的视频质量损失非常低,有0.038 dB的PSNR下降和0.56%的码率增加。 | 张强 袁春 | 2014 | 计算机科学与探索2014，8，5： | 4 |
| 20 | Information entropy of coding metasurface显示文摘Because of their exceptional capability to tailor the effective medium parameters,metamaterials have been widely used to control electromagnetic waves,which has led to the observation of many interesting phenomena,for example,negative refraction,invisibility cloaking,and anomalous reflections and transmissions.However,the studies of metamaterials or metasurfaces are mainly limited to their physical features;currently,there is a lack of viewpoints on metamaterials and metasurfaces from the information perspective.Here we propose to measure the information of a coding metasurface using Shannon entropy.We establish an analytical connection between the coding pattern of an arbitrary coding metasurface and its far-field pattern.We introduce geometrical entropy to describe the information of the coding pattern(or coding sequence)and physical entropy to describe the information of the far-field pattern of the metasurface.The coding metasurface is demonstrated to enhance the information in transmitting messages,and the amount of enhanced information can be manipulated by designing the coding pattern with different information entropies.The proposed concepts and entropy control method will be helpful in new information systems(for example,communication,radar and imaging)that are based on the coding metasurfaces. | Tie-Jun Cui Shuo Liu Lian-Lin Li | 2016 | Light(Science & Applications)2016，5，1： | 4 |
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