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| 1 | Regeneration dynamics of subalpine fir (Abies fargesii) forest across the altitudinal range in the Shennongjia Mountains, central China显示文摘Aims Age structure and regeneration dynamics have been used to infer population response to environmental events and reconstruct forest development history.The aim of this study was to characterize and examine the differences of the age structure and regeneration dynamics of subalpine fir(Abies fargesii)forest across the altitudinal range in the north and south aspects in the Shennongjia Mountains,central China.Methods Ten plots(20×20 m)at each altitudinal zone(i.e.the low elevation,the middle elevation and the high elevation)were established in both the north and south aspects of the Shennongjia Mountains,central China.Dendroecological techniques were applied to obtain information about ages of the trees in the plots.The population age structure was analyzed to investigate the regeneration dynamics across the altitudinal range.Important findings Fir regeneration dynamics and age structure were similar in both aspects,and a unimodal population age structure was found at different altitudinal sites of both aspects,indicating that environmental factors might play an important role in shaping the regeneration dynamics and age structure of A.fargesii across its altitudinal range.There was a sustained recruitment during the 19th century,but the regeneration was rarer in the last century at low and midelevations.A significant greater number of fir seedlings and saplings recruited at high elevations in the last century,and fir tree density at high elevations was significantly higher than that at low elevations.Thus,the fir population at the high elevations showed a significant increase in recruitment and stem density in the last century,and we propose that the gradual infilling of fir seedlings might result in changes in regeneration dynamics and stand structure of the subalpine fir forest at high elevations in the Shennongjia Mountains,central China. | Haishan Dang Kerong Zhang Yanjun Zhang Xunzhang Tong Quanfa Zhang | 2013 | Journal of Plant Ecology2013，6，1： | 6 |
| 2 | Squint-mode InISAR imaging based on nonlinear least square and coordinates transform显示文摘Aiming at the interferometric inverse synthetic aperture radar(InISAR) imaging in the presence of squint,we investigate the influence of squint on the InISAR imaging. First,coupling of the squint additive phase and the target azimuth/altitude coordinates to be solved may make the solution more difficult. Second,the squint angle may lead to estimation error of the vertical coordinates and distortion of the ultimate image. Traditional InISAR imaging algorithms can not solve the above two problems effectively,so we propose a new method which combines the nonlinear least square(NLS) and coordinates transform(CT) to estimate the target coordinates,and a three-dimensional(3-D) image consistent with the real target is obtained accordingly. Simulations show that the proposed method is effective for the squint-mode InISAR imaging. | LIU ChengLan HE Feng GAO XunZhang LI Xiang SHEN RongJun | 2011 | Science China(Technological Sciences)2011，54，12： | 5 |
| 3 | Novel imaging methods of stepped frequency radar based on compressed sensing显示文摘The theory of compressed sensing (CS) provides a new chance to reduce the data acquisition time and improve the data usage factor of the stepped frequency radar system. In light of the sparsity of radar target reflectivity, two imaging methods based on CS, termed the CS-based 2D joint imaging algorithm and the CS-based 2D decoupled imaging algorithm, are proposed. These methods incorporate the coherent mixing operation into the sparse dictionary, and take random measurements in both range and azimuth directions to get high resolution radar images, thus can remarkably reduce the data rate and simplify the hardware design of the radar system while maintaining imaging quality. Experiments from both simulated data and measured data in the anechoic chamber show that the proposed imaging methods can get more focused images than the traditional fast Fourier transform method. Wherein the joint algorithm has stronger robustness and can provide clearer inverse synthetic aperture radar images, while the decoupled algorithm is computationally more efficient but has slightly degraded imaging quality, which can be improved by increasing measurements or using a robuster recovery algorithm nevertheless. | Jihong Liu Shaokun Xu Xunzhang Gao Xiang Li | 2012 | Journal of Systems Engineering and Electronics2012，23，1： | 4 |
| 4 | A Sequential Bayesian Algorithm for DOA Tracking in Time-Varying Environments显示文摘This paper focuses on the Direction of arrival(DOA) tracking problem in dynamic environments where each source signal is modeled as a Gaussian process with time-varying mean and unknown covariance. In the presence of highly dynamic environment, benchmark algorithms usually have deteriorated performance. By treating the source signals as a function of the arrival angles, a sequential Bayesian tracking approach named Simultaneous angle-source update(SASU) is proposed based on the Maximum a posteriori(MAP) principle. The key feature of the proposed approach is to simultaneously update the arrival angles and the source signals in the Kalman filter step by converting the update process of the state vector into a joint optimization problem. An iterative Newton method to efficiently solve the joint optimization problem is proposed. The accuracy and robustness of the proposed SASU algorithm is demonstrated via simulations. | GAO Xunzhang LI Xiang Jason Filos DAI Wei | 2015 | Chinese Journal of Electronics2015，24，1： | 4 |
| 5 | High-speed Target ISAR Imaging via Compressed Sensing Based on Sparsity in Fractional Fourier Domain显示文摘 | LIU Jihong LI Xiang GAO Xunzhang ZHUANG Zhaowen | 2013 | Chinese Journal of Electronics2013，22，3： | 2 |
| 6 | Effect of Reaction Conditions on the Assembly, Structures and Fluorescent Sensing Behaviors of Cd(II) Metal-organic Complexes显示文摘 | LE Mao LUAN Jian ZHAO Xunzhang TANG Tang CHEN Panwen LIU Guocheng LIN Hongyan | 2016 | Chemical Research in Chinese Universities2016，32，1： | 1 |
| 7 | Role of the Tricuspid Annulus and the Eustachian Valve/Ridge on Atrial Flutter: Relevance to Catheter Ablation of the Septal Isthmus and a New Technique for Rapid Identification of Ablation Success显示文摘 | Hiroshi Nakagawa Ralph Lazzara Terrance Khastgir Karen J. Beckman James H. McClelland Shinobu Imai Jan V. Pitha Anton E. Becker Mauricio Arruda Mario D. Gonzalez Lawrence E. Widman Michael Rome Jeffrey Neuhauser Xunzhang Wang James D. Calame Maurice D. Go | 1996 | Circulation1996，，3： | 1 |
| 8 | A biased fairness assessment against developing countries显示文摘Since the adoption of the Paris Agreement, almost all countries have submitted their nationally determined contributions (NDCs) to the United Nations Framework Convention on Climate Change (UNFCCC) secretariat. Those submissions form the basis for the implementation of Paris Agreement. However, recent research [1] has shown that existing NDCs will not bring the world to the goal of limiting global temperature increase to below 2 °C above preindustrial levels, much less achieving the goal of limiting warming to 1.5 °C [2,3]. | Fei Teng Jiankun He Wenjie Dong Xunzhang Pan | 2019 | Science Bulletin2019，64，6： | 1 |
| 9 | Compressive radar imaging methods based on ast smoothed L0 algorithm显示文摘 | Jihong L Shaokun X Xunzhang G | 2012 | Procedia Engineering2012，29，： | 1 |
| 10 | Metric of Carbon Equity:Carbon Gini Index Based on Historical Cumulative Emission per Capita显示文摘这份报纸与调整使用 Lorenz 曲线和 Gini 索引到人均的历史的累积排放构造碳 Gini 索引在气候变化区域测量不平等。在空气的 70% 碳空间被用于的分析表演无可比拟分发,它在世界上几乎与在有在富人和穷人之间的最大的差距的一个国家的收入的一样。碳公平应该在气候议程是紧急和优先级。在这份报纸建立的碳 Gini 索引能被用来在碳空间的分发测量不平等并且在不同建议之中为碳公平的测量提供确定的指示物。引证 Teng, F. , J。他, X. 平底锅,等, 2011:碳公平公制:碳 Gini 索引基于历史的累积排放人均。副词。Clim。变化物件, 2 (3 ) , doi:10.3724/SP .J.1248.2011.00134。 | Fei Teng Jiankun He Xunzhang Pan Chi Zhang | 2011 | Advances in Climate Change Research2011，2，3： | 1 |
| 11 | Rationale and Study Design for Evaluating the Efficacy and Safety of Intracardiac Echocardiography-Guided Minimal-Fluoroscopy Ablation in Patients with Paroxysmal Atrial Fibrillation:A Non-Inferior,Multi-Center,Prospective Randomized Controlled Trial(PAF-ICE Trial)显示文摘The feasibility and safety of intracardiac echocardiography(ICE)-guided catheter ablation for atrial fibrillation(AF)using a minimal/zero-fluoroscopy approach have recently been reported.This approach helps to reduce ionizing radiation exposure and orthopedic complications resulting from using lead aprons.The objectives of this planned prospective,multicenter randomized controlled trial(RCT)(paroxysmal AF(PAF)-ICE trial;ChiCTR2000033624)are to evaluate the efficacy and safety of ICE-guided minimal-fluoroscopy ablation in patients with PAF and the impact on occupational hazards among lab staff.Patients will be randomized in a 1:1 ratio to 2 groups:minimal fluoroscopy group(n=216)and traditional approach group(n=216).In the minimal fluoroscopy group,an ICE catheter will be used for geometry/anatomic construction,transseptal puncture,catheter tracking,and effusion monitoring.Pulmonary vein isolation(PVI)will be performed using an open-irrigated radiofrequency SmartTouch Surround Flow or SmartTouch catheter(Biosense Webster,Diamond Bar,California,USA),and confirmed by a multipolar Lasso or PentaRay catheter(Biosense Webster).In the traditional approach group,an ICE catheter will not be used.Transseptal puncture will be performed under fluoroscopic guidance,with all geometries constructed by mapping the catheters.The primary efficacy endpoint is freedom from AF recurrence(without antiarrhythmic medications)at 12months after ablation.Other endpoints include duration of lead apron use,measures of intra-procedural efficiency,and peri-procedural complications.This RCT will evaluate the efficacy and safety of ICE-guided minimal-fluoroscopy ablation in patients with PAF,also evaluate the benefits to lab staff(regarding reducing occupational hazards)related to this“minimal/zero-fluoroscopy”and“leadless”mode. | Ruhong Jiang Xingpeng Liu Jidong Zhang Yu Chen Rui Wang Mengzuo Wu Deyong Long Jia Li Haixiong Wang Jie Fan Weizhu Ju Weili Ge Xu Liu Hai Deng Weijian Wang Pingzhen Yang Ding Li Xiaobo Huang Xiongtao Liu Hailong Tao Paul CZei Roderick Tung Xunzhang Wang Chenyang Jiang | 2021 | Cardiology Discovery2021，1，4： | 1 |
| 12 | Novel reference range selection method in InISAR imaging显示文摘Aiming at the reference range selection for different antennas in interferometric inverse synthetic aperture radar (InISAR) systems, this paper proposes a respective focusing (RF) method. The reference ranges for echoes of different antennas are selected respectively for RF, which is different from the traditional uniform focusing (UF) with the same reference range applied to all the antennas. First, a comparison between UF and RF for InISAR signal model considering the ranging error is given. Compared with RF, UF has an advantage in overcoming the ranging error differences between different antennas. Then the influence of ranging error upon the interferometric imaging with RF is investigated particularly, and it is found that the ranging error differences between different antennas are far smaller than the wavelength, which is advantageous to imaging. By comparing the capabilities of interferometric imaging between RF and UF, it is concluded that RF is a better choice in conquering problems such as image mismatching and phase ambiguity even with ranging errors. Simulations demonstrate the validity of the proposed method. | Chenglan Liu Feng He Xunzhang Gao Xiang Li Rongjun Shen | 2012 | Journal of Systems Engineering and Electronics2012，23，4： | 0 |
| 13 | Identification of differential mRNA and lncRNA expression in AcMNPV-infected Sf9 cells显示文摘Sf9Sf9 are the ovarian cells of Spodoptera frugiperda that is the host of Autographa californica multiple nucleopolyhedrovirus(AcMNPV),and hence can serve as an effective test vehicle to understand the AcMNPV infection mechanism.In this study,through high-throughput sequencing technology using samples collected from Sf9 cells at different time points after AcMNPV infection,3463 pieces of time-series differentially expressed RNA(1,200 mRNA and 2,263 lncRNA)are identified and justified by experimental verification of randomly selected samples from them,proving the validity of the bioinformatical analysis on this topic.Functional enrichment analysis and target prediction are performed on those differentially expressed RNA,from which the major functional enrichment distribution of those differentially expressed mRNA is derived.It has been found that the differential genes are mainly in the cellular anatomical entity and intracellular in terms of the cellular component,and in the binding and catalytic activity in terms of the molecular function.Also,the differential mRNA are mainly concentrated in global and overview maps,signal transduction,infectious diseases,and viral,etc.Moreover,those mRNA targeted by lncRNA are predicted.The correlation between those differentially expressed lncRNA and mRNA indicates that lncRNA is very likely playing an important role in the interaction between virus and host.Aided by an advanced co-expression analysis approach,the“hub”RNA is also identified.The study in this work pave the way for further analyzing and understanding how AcMNPV escapes from the host’s immunity,manipulates the host to realize the selfmultiplication,and realizes the timely conversion between its two particle forms,laying the foundation for uncovering the host’s immune response process. | TIEJUN ZHAO RIQIANG DENG MENGQIU CHEN XUNZHANG WANG | 2022 | BIOCELL2022，46，7： | 0 |
| 14 | Comparing and evaluating the nationally determined contributions of the top six emitters under the Paris Agreement goals显示文摘Comparing and evaluating the Nationally Determined Contribution(NDC) is an important element in global stocktake in the post-Paris climate negotiations, aimed at closing the emissions gap with the Paris Agreement goals. To date, however, there has still been no explicit guideline or method. By applying emissions allowance allocated by 16 schemes as benchmarks, this paper tries to compare and evaluate the NDCs of the top six emitters, which jointly account for about 70% of the world's CO_2 emissions. Results show that the four developed countries' NDCs lack ambition with respect to most allocations under 2℃ and all under 1.5℃, indicating they need to substantially ratchet up their NDCs and lead elevating mitigation. Evaluating cumulative emissions is more likely to clarify the ambition and fairness of China's NDC. If considering cumulative emissions, China's NDC is aligned with the median of cumulative allowances under 2℃ and within the 1.5℃ range. The Paris Agreement invited the Parties to communicate the mid-century low emissions strategies. This paper also tries to explore the mid-century mitigation in the perspective of allocations, which might provide decision-makers with some useful information when envisaging the post-NDC mitigation. | Xunzhang Pan Jie Tao Hailin Wang | 2018 | Chinese Journal of Population,Resources and Environment2018，16，3： | 0 |
| 15 | ISAR target recognition based on non-negative sparse coding显示文摘Aiming at technical difficulties in feature extraction for the inverse synthetic aperture radar (ISAR) target recognition, this paper imports the concept of visual perception and presents a novel method, which is based on the combination of non-negative sparse coding (NNSC) and linear discrimination optimization, to recognize targets in ISAR images. This method implements NNSC on the matrix constituted by the intensities of pixels in ISAR images for training, to obtain non-negative sparse bases which characterize sparse distribution of strong scattering centers. Then this paper chooses sparse bases via optimization criteria and calculates the corresponding non-negative sparse codes of both training and test images as the feature vectors, which are input into k neighbors classifier to realize recognition finally. The feasibility and robustness of the proposed method are proved by comparing with the template matching, principle component analysis (PCA) and non-negative matrix factorization (NMF) via simulations. | Ning Tang Xunzhang Gao Xiang Li | 2012 | Journal of Systems Engineering and Electronics2012，23，6： | 0 |
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