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| 1 | Research on the application of 4-weighted fractional Fourier transform in communication system显示文摘The paper reveals the relationship between the weighting coefficients and weighted functions via the research of coefficients matrix and based on the original definition of 4-weighted fractional Fourier transform(4-WFRFT).The multi-parameters expression of weighting coefficients are given.Moreover, the 4-WFRFT of discrete sequences is defined by introducing DFT into it, which makes it suitable for digital communication systems.After analyzing the properties of WFRFT, a typical scheme for modulation/demodulation is proposed, which could make the statistics properties of the real and image part on both of the time and frequency domain and the phase properties have a significant variation.Such a variation could be controlled by the adjustment of transform parameters.If the WFRFT of multi-parameters is implemented, it will be more difficult to intercept and capture the modulated signals than normal. | MEI Lin SHA XueJun RAN QinWen ZHANG NaiTong | 2010 | Science China(Information Sciences)2010，53，6： | 25 |
| 2 | MP-WFRFT and Constellation Scrambling Based Physical Layer Security System显示文摘In this paper, a multiple parameters weighted fractional Fourier transform(MPWFRFT) and constellation scrambling(CS) method based physical layer(PHY) security system is proposed. The proposed scheme is executed by two steps. In the first step, MPWFRFT, implemented as the constellation beguiling(CB) method, is applied to change the signal's identity. In the second step the additional pseudo random phase information, regarded as the encryption key, is attached to the original signal to enhance the security. Typically, the pseudo random phase information can be removed effectively by the legitimate receiver. In contrast to the cryptography based encryption algorithms and the conventional PHY secrecy techniques, the main contribution of the proposed scheme is concentrated on the variation in signal's characteristics. Simulation results show that the proposed scheme can prevent the exchanging signal from eavesdroppers' classifi cation or inception. Moreover, the proposed scheme can guarantee the BER performance at a tolerate increasing in computational complexity for the legitimate receivers. | FANG Xiaojie SHA Xuejun LI Yue | 2016 | China Communications2016，13，2： | 26 |
| 3 | Guaranteeing Wireless Communication Secrecy via a WFRFT-Based Cooperative System显示文摘In this paper, a weighted fractional Fourier transform(WFRFT) based cooperative overlay system, aiming to guarantee physical layer(PHY) security, is proposed. The paper elaborates how WFRFT and physical layer properties of the wireless medium are collaborated to guarantee the secrecy of wireless transmissions. In the proposed system, WFRFT is first preform on the secret data, such that the transmitted signal is distorted and can only be neutralized by inverse-WFRFT with the same parameter. And then two streams of the transformed sequences that bearing different messages are cooperatively and simultaneously transmitted to two legitimate receivers via a beamforming-liked method, respectively. In general, both the rapid spatial decorrelation property and the inherent security features of WFRFT are leveraged, such that only the eavesdropper's is degraded, and hence, the wireless communication secrecy is reliably guaranteed. Numerical simulations are conducted to evaluate the performance of the proposed system in terms of the average bit error rate and the secrecy capacity. | Fang Xiaojie Sha Xuejun Mei Lin | 2015 | China Communications2015，12，9： | 18 |
| 4 | BER analysis of STBC hybrid carrier system based on WFRFT with frequency domain equalization显示文摘The inherent characteristic of hybrid carrier(HC) scheme based on the weighted-type fractional Fourier transform(WFRFT) is revealed. The proposed linear combination of single carrier(SC) and multicarrier's(MC) characteristics is helpful to balance the conflicting requirements and achieve the comparative analysis of SC/MC. As an example, analytical SER/BER expressions of HC system with zero forcing(ZF)and minimum mean square error(MMSE) equalization are derived. In addition, the derived BER expressions are extended to multi-input systems. A unified framework of space time block code(STBC) HC scheme is proposed with two WFRFT modules at the transmitter or receiver, where STBC-SC and STBC-MC systems are the special cases of the novel structure. | Zhenduo WANG Lin MEI Xuejun SHA Naitong ZHANG | 2018 | Science China(Information Sciences)2018，61，8： | 5 |
| 5 | Bushen Qiangjin capsule(补肾强筋胶囊) inhibits the Wnt/β-catenin pathway to ameliorate papain-induced knee osteoarthritis in rats显示文摘OBJECTIVE:To evaluate the molecular mechanism underlying the beneficial effect of Bushen Qiangjin capsule(补肾强筋胶囊,BSQJ),a Traditional Chinese Medicine,on knee osteoarthritis(KOA).METHODS:In the present study,32 female Sprague-Dawley rats were randomly divided into four groups:control,KOA,high-dose BSQJ(H-BSQJ),and low-dose BSQJ(L-BSQJ).After successfully establishing the KOA model by intra-articular injection of papain,H-BSQJ and L-BSQJ groups were intragastrically administered 0.243 and 0.122 g/kg BSQJ,respectively,daily for 6 weeks.At the end of the experiment,knee articular cartilage tissues of rats were collected for evaluation by hematoxylin and eosin staining,Safranin O-Fast Green staining,and terminal deoxynucleotidyl transferase-mediated d UTP nick-end labeling assay.Serum interleukin-1βand tumor necrosis factor-αlevels of rats were detected with an enzyme-linked immunosorbent assay method.Gene expression of Wnt-4,β-catenin,Frizzled-2,glycogen synthase kinase-3β(GSK-3β),cysteinyl aspartate-specific proteinases 3 and 9(caspases 3 and 9),collagen typeⅡalpha 1(Col2 a1),and matrix metalloproteinases 1 and 13(MMP-1 and MMP-3)of rat knee articular cartilage was quantified by reverse transcription-quantitative polymerase chain reaction analysis.Wnt-4,β-catenin,Frizzled-2,GSK-3β,cleaved caspase-3,and cleaved caspase-9 protein expression in rat knee articular cartilage was determined by western blot analysis.RESULTS:BSQJ obviously reduced pathological damage and matrix degradation of articular cartilage in KOA rats.Compared with the KOA group,H-BSQJ rats exhibited downregulated m RNA and protein expression of Wnt-4,β-catenin,Frizzled-2,and caspase-3,as well as upregulated m RNA and protein expression of GSK-3β.In addition,H-BSQJ significantly increased m RNA expression of Col2 a1 and decreased m RNA expression of MMP-1 and MMP-13.CONCLUSION:BSQJ exerted a beneficial effect on KOA by a mechanism involving downregulation of the Wnt/β-catenin pathway,which inhibited both cartilage extracellular matrix degradation and chondrocyte apoptosis to ameliorate KOA in rats. | YAO Nan CHEN Guocai LU Yanyan XU Xuemeng ZHAO Chuanxi HUANG Xuejun LIU Wengang PENG Sha WU Huai | 2021 | Journal of Traditional Chinese Medicine2021，41，6： | 5 |
| 6 | Joint Timing and Frequency Synchronization for OFDM based on Fractional Fourier Transform显示文摘 | Tang Xun Sha Xuejun | 2010 | China Communications2010，7，5： | 5 |
| 7 | A Novel Resource Allocation Algorithm based on Downlink and Uplink Decouple Access Scheme in Heterogeneous Networks显示文摘Traditional cellular network requires that a user equipment(UE) should associate to the same base station(BS) in both the downlink(DL) and the uplink(UL). Based on dual connectivity(DC) introduced in LTE-Advanced R12, DL/UL decouple access scheme has been proposed, which is especially suitable for heterogeneous networks(Het Nets). This paper is the pioneer to take the DL/UL decouple access scheme into consideration and develop a novel resource allocation algorithm in a two-tier Het Net to improve the total system throughput in the UL and ease the load imbalance between macro base stations(MBSs) and pico base stations(PBSs). A model is formulated as a nonlinear integer programming, and the proposed algorithm is a sub-optimal algorithm based on the graph theory. First, an undirected and weighted interference graph is obtained. Next, the users are grouped to let users with large mutual interferences to be assigned to different clusters. Then, the users in different clusters are allocated to different resource blocks(RBs) by using the Hungarian algorithm. Simulation results show that the proposed algorithm can provide great promotions for both the total system throughput and the average cell edge user throughput and successfully ease the load imbalance between MBSs and PBSs. | Laiwei Jiang Xuejun Sha Xuanli Wu Naitong Zhang | 2016 | China Communications2016，13，6： | 4 |
| 8 | Digital computation of the weighted-type fractional Fourier transform显示文摘The paper reveals the time-frequency symmetric property of the weighted-type fractional Fourier transform (WFRFT) by investigating the original definition of the WFRFT, and proposes a discrete algorithm of the WFRFT based on the weighted discrete Fourier transform (WDFT) algorithm with constraint conditions of the definition of the WFRFT and time-domain sampling. When the WDFT is considered in digital computation of the WFRFT, the Fourier transform in the definition of the WFRFT should be defined in frequency (Hz) but not angular frequency (rad/s). The sampling period Δt and sampling duration T should satisfy Δt = T/N = 1/N(1/2) when N-point DFT is utilized. Since Hermite-Gaussian functions are the best known eigenfunctions of the fractional Fourier transform (FRFT), digital computation based on eigendecomposition is also carried out as the additional verification and validation for the WFRFT calculation. | MEI Lin ZHANG QinYu SHA XueJun ZHANG NaiTong | 2013 | Science China(Information Sciences)2013，56，7： | 4 |
| 9 | Hybrid C a rrie r S prea d Based on 4-Weighted T ra nsform Spectrum System Fractional Fourier显示文摘Spread Spectrum (SS) is a promising technique to resist interference in wireless communication system. In order to further improve this capability, this paper proposes a Hybrid Carrier (HC) SS system, combining 4-Weighted Fractional Fourier Transform (4-WFRFT) with SS technique. In this HC-SS system, due to the property of 4-WFRFT, the signal energy of proposed system is distributed on the time-frequency plane more evenly and symmetrically, compared with the existing Single-Carrier (SC) and Multi-Carrier (MC) spread spectrum systems. In the selective channel, the proposed method can split the interference to a more broad range in order to reduce the influence, resulting in the better system performance. In addition, proposed system can be seen as the convergence of the existing SS techniques, which is a main feature in future. | Qiu Xin Sha Xuejun Mei Lin | 2012 | China Communications2012，9，1： | 4 |
| 10 | A green eco-environment for sustainable development:framework and action显示文摘Following its 40-year reform and‘Open Door’policy,China has recently proposed a new approach to green development and rural revitalization—the idea of Agriculture Green Development(AGD),with the key feature of creating a green eco-environment.In this minireview we introduce the definition,theory,framework and major components of a green eco-environment as a key part of the AGD.We define a green eco-environment as including four key elements or measures:(1)a green ecoenvironmental indicator system;(2)environmental monitoring and warning networks;(3)emission standards and environmental thresholds for key pollutants;(4)emission controls and pollution remediation technologies.We have used Quzhou County(a typical county in the center of the North China Plain)as an example to show how detailed air,water and soil monitoring networks,as well as improved farmer practices and pollution control measures(especially ammonia emission mitigation and PM2.5 pollution reduction),can begin to create a green eco-environment in China and that AGD is possible.We conclude by stressing the need to improve the framework and practice for a green eco-environment,especially the importance of linking proposals and practices for a green eco-environment with the United Nations high priority Sustainable Development Goals. | Xuejun LIU Wen XU Zhipeng SHA Yangyang ZHANG Zhang WEN Jingxia WANG Fusuo ZHANG Keith GOULDING | 2020 | Frontiers of Agricultural Science and Engineering2020，7，1： | 3 |
| 11 | 8-Weighted-Type Fractional Fourier Transform Based Three-Branch Transmission Method显示文摘To improve the bit error rate(BER) performance of multiple input multiple output(MIMO) systems with low complexity, a three-branch transmission scheme employing 8-weighted-type fractional Fourier transform(8-WFRFT) module is proposed. In the proposed scheme, the original signal is first decomposed into eight sub-signals and then merged into three component signals by the same carrier pattern. The three signals have mathematical constraint relations among themselves that can counteract the channel fading. They are simultaneously transmitted via three independent antennas after delay regulating. At the receiver, an inverse 8-WFRFT module is employed to obtain the estimated original signal by processing the received signal. Then, the bit error rate(BER) performance, transmitting power, transmission rate, power spectrum and computational complexity of the proposed scheme are analysed in detail. Numerical results show that the proposed scheme has a superior performance compared to STBC based three-antenna transmission scheme, in terms of BER performance. | Jing Li Xuejun Sha Xiaojie Fang Lin Mei | 2018 | China Communications2018，15，9： | 2 |
| 12 | Hybrid coordinated strategy of downlink coordinated multi-point transmission显示文摘Coordinated multi-point(CoMP) transmission is put forward in the long term evolution-advanced(LTE-A) system to improve both average and cell-edge throughput. CoMP-joint processing(JP) scheme can get a larger cell-edge throughput and a lower bit error rate(BER) than the CoMP-coordinated beamforming(CB) scheme, but it also has higher complexity due to data sharing. A hybrid coordinated strategy with parameter α, which indicates the proportion of users employing the CoMP-JP scheme,is proposed to apply the CoMP-JP scheme to improve the poorer communication quality of cell edge and employ the CoMP-CB scheme for other users to enhance average throughput and spectral efficiency. This paradigm selects users defined by the certain threshold of signal to interference plus noise power ratio(SINR)corresponding to the parameter α to the CoMP-JP scheme. This paper compares the BER performance between the block diagonalization(BD) based precoding and the linear precoders by maximizing signal to leakage and noise ratio(SLNR), and also indicates that the SLNR based precoding algorithm gets lower BER than the BD based precoding algorithm with certain signal-to-noise ratios(SNRs). Finally, this paper discusses that the system performance is partially affected by the percentage of CoMP-JP users and concludes that 50% of users sorted to communicate under the CoMP-JP scheme will reach the best system performance. | Zhuoming Li Yuqi Liu Yu Zhang Peng Wang Chunyang Tian Xuejun Sha | 2015 | Journal of Systems Science & Complexity2015，28，5： | 2 |
| 13 | Time-Domain Dual Component Computation Diversity Based on Generalized Hybrid Carrier显示文摘In this paper,the concept of computation diversity is proposed by employing generalized hybrid carrier(GHC)system.The signal is backed up by transform-domain computation to enhance the anti-fading capability.Theoretical analysis is presented to demonstrate the superiority of the proposed method.Numerical simulations in doubly-selective fading channels are provided to verify the results.The bit error rate(BER)performance is guaranteed with a small computational complexity increment.The proposed method not only extends the new diversity dimension,but also improves the diversity gain of the system without occupying additional wireless resources.Moreover,the proposed method shows good adaptability with single carrier modulation and improves diversity performance.As the simulation results shown,time-domain dual component computation diversity(TDC-CD)has 1d B BER gain and 0.1diversity gain at high signal-to-noise ratio,and single carrier system with TDC-CD achieves 2d B BER gain at 10~(-4). | Yuqing Feng Xuejun Sha Yong Li Xiaojie Fang Yusi Zhang | 2021 | China Communications2021，18，10： | 2 |
| 14 | Catalyzing Random Access at Physical Layer for Internet of Things:An Intelligence Enabled User Signature Code Acquisition Approach显示文摘Exploiting random access for the underlying connectivity provisioning has great potential to incorporate massive machine-type communication(MTC)devices in an Internet of Things(Io T)network.However,massive access attempts from versatile MTC devices may bring congestion to the IIo T network,thereby hindering service increasing of IIo T applications.In this paper,an intelligence enabled physical(PHY-)layer user signature code acquisition(USCA)algorithm is proposed to overcome the random access congestion problem with reduced signaling and control overhead.In the proposed scheme,the detector aims at approximating the optimal observation on both active user detection and user data reception by iteratively learning and predicting the convergence of the user signature codes that are in active.The crossentropy based low-complexity iterative updating rule is present to guarantee that the proposed USCA algorithm is computational feasible.A closed-form bit error rate(BER)performance analysis is carried out to show the efficiency of the proposed intelligence USCA algorithm.Simulation results confirm that the proposed USCA algorithm provides an inherent tradeoff between performance and complexity and allows the detector achieves an approximate optimal performance with a reasonable computational complexity. | Xiaojie Fang Xinyu Yin Xuejun Sha Jinghui Qiu Hongli Zhang | 2021 | China Communications2021，18，10： | 1 |
| 15 | Damage evolution of yttria-stabilized zirconia induced by He irradiation显示文摘 | Tengfei Yang Xuejun Huang Yuan Gao Chenxu Wang Yanwen Zhang Jianming Xue Sha Yan Yugang Wang | 2011 | Journal of Nuclear Materials2011，，1： | 1 |
| 16 | The approach to carrier scheme convergence based on 4-weighted fractional Fourier transform 显示文摘 | MEI Lin SHA Xuejun ZHANG Naitong | | IEEE Communication Letters0，4，6： | 1 |
| 17 | On interference suppression in doubly-dispersive channels with hybrid single-multi carrier modulation and an MMSE iterative equalizer 显示文摘 | WANG Kun SHA Xuejun MEI Lin | | IEEE Wireless Communications Letters0，1，5： | 1 |
| 18 | Performance analysis of hybrid carrier system with MMSE equalization over doubly-dispersive channels 显示文摘 | WANG Kun SHA Xuejun MEI Lin | | IEEE Communications Letters0，6，7： | 1 |
| 19 | 2,3,7,8-Tetrachlorodibenzo-p-dioxin promotes migration ability of primary cultured rat astrocytes via aryl hydrocarbon receptor显示文摘Emerging evidence showed that 2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) could induce expression of certain reactivation-associated genes in astrocytes, however, the consequent cellular effects and molecular mechanisms are still unclear. During the process of astrocyte reactivation, migration is a critical cellular event. In the present study, we employed woundhealing assay and Transwell? motility assay to explore the effects of TCDD on cell migration in primary cultured rat cortical astrocytes. We found that upon TCDD treatments at relative low concentrations(10^(-10) and/or 10^(-9) mol/L), the ability of primary astrocytes to migrate horizontally and vertically was promoted. In line with this cellular effect, the mR NA expression of two promigratory genes, including cell division cycle 42(CDC42) and matrix metalloproteinase 2(MMP2)was induced by TCDD treatment. Dioxin exerts its toxic effects mainly through aryl hydrocarbon receptor(AhR) pathway. So the role of AhR pathway in the pro-migratory effects of TCDD was examined using an AhR antagonist, CH223191. We found that application of CH223191 significantly reversed the pro-migratory effects of TCDD. Interestingly, the basal ability of horizontal migration as well as basal levels of CDC42 and MMP2 expression were dramatically reduced suggesting a possible physiological role of AhR in maintaining the endogenous migration ability of the primary astrocytes. These findings support the notion that dioxin promotes astrocyte reactivation at molecular and cellular levels. | Yangsheng Chen Rui Sha Li Xu Yingjie Xia Yiyun Liu Xuejun Li Heidi Qunhui Xie Naijun Tang Bin Zhao | 2019 | Journal of Environmental Sciences2019，31，2： | 1 |
| 20 | Low complexity bit loading algorithm for OFDM system显示文摘A new approach to loading for orthogonal frequency division multiplexing (OFDM) system is proposed, this bit-loading algorithm assigns bits to different subchannels in order to minimize the transmit energy. In the algorithm, first most bit are allocated to each subchannels according to channel condition, Shannon formula and QoS require of the user, then the residual bit are allocated to the subchannels bit by bit. In this way the algorithm is efficient while calculation is less complex. This is the first time to load bits with the scale following Shannon formula and the algorithm is of O (4N) complexity. | Yang Yu Sha Xuejun Zhang Zhonghua | 2006 | Journal of Systems Engineering and Electronics2006，17，1： | 1 |
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