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36篇 您的检索式:作者名="Liu Yuewei"
    题名 作者 年代 出处 被引量
1Improved quantum bacterial foraging algorithm for tuning parameters of fractional-order PID controller显示文摘The quantum bacterial foraging optimization(QBFO)algorithm has the characteristics of strong robustness and global searching ability. In the classical QBFO algorithm, the rotation angle updated by the rotation gate is discrete and constant,which cannot affect the situation of the solution space and limit the diversity of bacterial population. In this paper, an improved QBFO(IQBFO) algorithm is proposed, which can adaptively make the quantum rotation angle continuously updated and enhance the global search ability. In the initialization process, the modified probability of the optimal rotation angle is introduced to avoid the existence of invariant solutions. The modified operator of probability amplitude is adopted to further increase the population diversity.The tests based on benchmark functions verify the effectiveness of the proposed algorithm. Moreover, compared with the integerorder PID controller, the fractional-order proportion integration differentiation(PID) controller increases the complexity of the system with better flexibility and robustness. Thus the fractional-order PID controller is applied to the servo system. The tuning results of PID parameters of the fractional-order servo system show that the proposed algorithm has a good performance in tuning the PID parameters of the fractional-order servo system.LIU Lu SHAN Liang DAI Yuewei LIU Chenglin QI Zhidong 2018Journal of Systems Engineering and Electronics2018,29,1:6
2Essential role of the CUL4B ubiquitin ligase in extra-embryonic tissue development during mouse embryogenesis显示文摘CUL4B ubiquitin ligase 基因的变化有原因地被连接到 syndromic X 连接智力迟钝(XLMR ) 。然而,在 neuronal 和发展缺点的 CUL4B 变化的病原的角色没被理解。我们与 Cul4b 的指向的混乱产生了老鼠,并且与显著生长抑制观察了胚胎的致命性并且在胚胎外的纸巾增加了 apoptosis。Cul4b,然而并非它的 paralog Cul4a,在胚胎外的纸巾驿站培植在高水平被表示。在一根胚胎外的房间线的 CUL4B 表示的 Silencing 导致了 CUL4 底层 p21 Cip1/WAF 和 G2/M 房间周期逮捕 Cip1/WAF 。Cul4b 的 Epiblast 特定的删除阻止了胚胎的致命性并且产生了可行 Cul4b 空老鼠。因此,当时在胚胎非必需合适, Cul4b 在胚胎外的纸巾执行一个必要发展角色。我们的学习提供策略产生可行 Cul4b 缺乏的老鼠为潜在的 neuronal 和人的 CUL4B XLMR 病人的行为的缺乏建模。Liren Liu Yan Yin Yuewei Li Lisa Prevedel Elizabeth H Lacy Liang Ma Pengbo Zhou 2012Cell Research2012,22,8:6
3Chromopeptide A, a highly cytotoxic depsipeptide from the marine sediment-derived bacterium Chromobacterium sp. HS-13-94显示文摘A bicyclic depsipeptide, chromopeptide A(1), was isolated from a deep-sea-derived bacterium Chromobacterium sp. HS-13-94. Its structure was determined by extensive spectroscopic analysis and by comparison with a related known compound. The absolute configuration of chromopeptide A was established by X-ray diffraction analysis employing graphite monochromated Mo K_α radiation(λ ? 0.71073 ?) with small Flack parameter 0.03. Chromopeptide A suppressed the proliferation of HL-60, K-562, and Ramos cells with average IC_(50) values of 7.7, 7.0, and 16.5 nmol/L, respectively.Zhenfang Zhou Xin Wang Hui Zhang Jingya Sun Linghui Zheng Hongchun Liu Jidong Wang Aijun Shen Meiyu Geng Yuewei Guo 2015Acta Pharmaceutica Sinica B2015,5,1:6
4Survey of reefs based on Landsat 8 operational land imager(OLI)images in the Nansha Islands, South China Sea显示文摘A detailed survey of the reefs in the Nansha Islands' sea that are of strategic importance is conducive to their future development. In this study, a total of 50 Landsat 8 operational land imager(OLI) images were used to analyze the geological features and spectral characteristics of the Nansha reefs. The exposed islands/sandbanks,reef flats and sub-tidal reefs were identified with the near-infrared band, the red and green bands, and the blue band, respectively. Based on the relationships among various characteristics and bands illustrated in the OLI images, the maximum between-cluster variance threshold algorithm(OTSU method) and the mathematical morphology were employed to extract characteristic parameters of the spatial geometry of the reefs from top to bottom, which were subsequently operated by a series of post-processing methods such as vectorization,simplification and topological analysis. Among the 132 standalone reefs and 16 atolls that are identified in the study, four reefs have yet to be named in the Standard Names of Various Islands in the South China Sea and the website Nansha Islands Online(http://gffzzd4db47f6efa542b8h0qvx65ffq9nv65wb.ffgz.tsg.suse.edu.cn/). Another 24 ones are exposed to the atmosphere even during high tides. Taiping Island with an area of 0.57 km^2 represents the largest exposed geological feature. This study demonstrated the applicability of medium-resolution satellite images to derive the coral reef information effectively and thus provided information for the related departments that are responsible to manage the coast.An improved resolution of multispectral bands with the panchromatic band in higher spatial resolution(15 m for OLI image) is expected to provide an optimum satellite based approach to map marine habitats.DUAN Yuewei LIU Yongxue LI Manchun ZHOU Minxi YANG Yuhao 2016Acta Oceanologica Sinica2016,35,10:5
5Onshore-offshore wind energy resource evaluation based on synergetic use of multiple satellite data and meteorological stations in Jiangsu Province,China显示文摘The demand for efficient and cost-effective renewable energy is increasing as traditional sources of energy such as oil,coal,and natural gas,can no longer satisfy growing global energy demands.Among renewable energies,wind energy is the most prominent due to its low, manageable impacts on the local environment.Based on meteorological data from 2006 to 2014 and multi-source satellite data (i.e.,Advanced Scatterometer,Quick Scatterometer,and Windsat)from 1999 to 2015,an assessment of the onshore and offshore wind energy potential in Jiangsu Province was performed by calculating the average wind speed,average wind direction,wind power density, and annual energy production (AEP).Results show that Jiangsu has abundant wind energy resources,which increase from inland to coastal areas.In-onshore areas, wind power density is predominantly less than 200 W/m^2, while in offshore areas,wind power density is concentrates in the range of 328-500 W/m^2.Onshore areas comprise more than 13,573.24 km^2,mainly located in eastern coastal regions with good wind farm potential The total wind power capacity in onshore areas could be as much as 2.06×10^5 GWh.Meanwhile,offshore wind power generation in Jiangsu Province is calculated to reach 2×10^6 GWh, which is approximately four times the electricity demand of the entire Jiangsu Province.This study validates the effective application of Advanced Scatterometer,Quick Scatterometer,and Windsat data to coastal wind energy monitoring in Jiangsu.Moreover,the methodology used in this study can be effectively applied to other similar coastal zones.Xianglin WEI Yuewei DUAN Yongxue LIU Song JIN Chao SUN 2019Frontiers of Earth Science2019,13,1:4
6Prognostic value of pre-and post-transplantation 18F-fluorodeoxyglucose positron emission tomography results in non-Hodgkin lymphoma patients receiving autologous stem cell transplantation显示文摘Objective: High-dose chemotherapy(HDC) followed by autologous stem cell transplantation(ASCT) is the standard of care in the upfront or relapsed/refractory setting in some patients with non-Hodgkin lymphoma(NHL).However,a proportion of patients do not respond to ASCT.^(18)F-fluorodeoxyglucose(FDG) positron emission tomography(PET)/computed tomography(CT) has been widely used for staging,response evaluation,and prognosis prediction.Here,we investigated the prognostic role of PET/CT in NHL patients before and after ASCT.Methods: A retrospective study was conducted at Peking University Cancer Hospital.All NHL patients who underwent ASCT between March 2010 and July 2016 were identified.Patients who had PET/CT scan before and after ASCT were included.Deauville criteria(5-point scale) were used to interpret PET scans.Univariate and multivariate survival analyses were performed using Cox regression.The predictive value of PET scanning was estimated by comparing the area under the receiver operating characteristic(ROC) curve.Results: In total,79 patients were enrolled in this study.In univariate analysis,pre-and post-ASCT PET result was identified as prognostic factors for 3-year progression-free survival(PFS) and overall survival(OS).Patients with negative pre-ASCT PET result demonstrated significantly better PFS(84.2% vs.54.2%) and OS(89.2% vs.63.6%) than patients with positive pre-ASCT PET result.PFS(91.6% vs.25.3%) and OS(96.5% vs.36.8%) were also significantly different between patients with negative and positive post-ASCT PET result.Multivariate analysis also showed a significant association between survival and post-ASCT PET result.ROC analysis revealed that the predictive value of post-ASCT PET result was superior to that of pre-ASCT PET result alone.Combined pre-and post-ASCT PET result is better for predicting outcomes in patients with NHL receiving transplantation.Deauville criteria score >3 was identified as the best cutoff value for post-ASCT PET.Conclusions: Post-ASCT PET result was more important than pre-ASCT PET result in predicting outcomes for NHL patients who underwent ASCT.The prognostic significance can be improved when combining preASCT PET result with post-ASCT PET result.Deauville criteria can be used for interpreting PET scans in this scenario.Zhitao Ying Lan Mi Xuejuan Wang Yuewei Zhang Zhi Yang Yuqin Song Xiaopei Wang WenZheng Ningjing Lin Meifeng Tu Yan Xie Lingyan Ping Chen Zhang Weiping Liu LijuanDeng Jun Zhu 2017Chinese Journal of Cancer Research2017,29,6:3
7Neutron halo state of ^(13)C显示文摘Angular distributions for the 12C(d, p)13C transfer reactions have been measured at Ed = 11.8 MeV, and compared with those of the DWBA calculations. By means of this comparison, density distributions of the last neutron in the ground state and the first 1/2+ state of 13C are extracted. The properties of these states in 13C have also been studied in the framework of the nonlinear relativistic mean-field theory with NL-SH parameters. It is found that the first l/2+ state in 13C is a neutron halo state shown by both the experimental and theoretical density distributions of the last neutron.LIU Zuhua, LIN Chengjian, LI Zhichang, ZHANG Huanqiao, CHEN Baoqiu, MA Zhongyu, WU Yuewei, LIU Jiancheng & LI ShuyuanChina Institute of Atomic Energy, Beijing 102413, China 2001Chinese Science Bulletin2001,46,1:3
8PHOTOREALISTIC COMPUTER GRAPHICS FORENSICS BASED ON LEADING DIGIT LAW显示文摘As the advent and growing popularity of image rendering software,photorealistic computer graphics are becoming more and more perceptually indistinguishable from photographic images.If the faked images are abused,it may lead to potential social,legal or private consequences.To this end,it is very necessary and also challenging to find effective methods to differentiate between them.In this paper,a novel leading digit law,also called Benford's law,based method to identify computer graphics is proposed.More specifically,statistics of the most significant digits are extracted from image's Discrete Cosine Transform(DCT) coefficients and magnitudes of image's gradient,and then the Support Vector Machine(SVM) based classifiers are built.Results of experiments on the image datasets indicate that the proposed method is comparable to prior works.Besides,it possesses low dimensional features and low computational complexity.Xu Bo Wang Junwen Liu Guangjie Dai Yuewei 2011Journal of Electronics(China)2011,28,1:3
9Deep-blue organic light-emitting diodes based on a doublet d-f transition cerium(Ⅲ) complex with 100% exciton utilization efficiency显示文摘Compared to red and green organic light-emitting diodes(OLEDs),blue OLEDs are still the bottleneck due to the lack of efficient emitters with simultaneous high exciton utilization efficiency(EUE)and short excited-state lifetime.Different from the fluorescence,phosphorescence,thermally activated delayed fluorescence(TADF),and organic radical materials traditionally used in OLEDs,we demonstrate herein a new type of emitter,cerium(Ⅲ)complex Ce-1 with spin-allowed and parity-allowed d-f transition of the centre Ce^(3+) ion.The compound exhibits a high EUE up to 100% in OLEDs and a short excited-state lifetime of 42 ns,which is considerably faster than that achieved in efficient phosphorescence and TADF emitters.The optimized OLEDs show an average maximum external quantum efficiency(EQE)of 12.4% and Commission Internationale de L’Eclairage(CIE)coordinates of(0.146,0.078).Liding Wang Zifeng Zhao Ge Zhan Huayi Fang Hannan Yang Tianyu Huang Yuewei Zhang Nan Jiang Lian Duan Zhiwei Liu Zuqiang Bian Zhenghong Lu Chunhui Huang 2020Light(Science & Applications)2020,9,1:3
10Changes in the frequency of myeloid-derived suppressor cells after transarterial chemoembolization with gelatin sponge microparticles for hepatocellular carcinoma显示文摘Purpose: A series of clinical studies have established the safety and efficacy of transcatheter arterial chemoembolization(TACE) with gelatin sponge microparticles(GSMs) in treating hepatocellular carcinoma(HCC). HCC can lead to obvious necrosis inside tumors, especially larger ones, although it is unclear whether such necrotic tumor tissue can induce favorable immune reactions against the tumor. Myeloid-derived suppressor cells(MDSCs)have immunosuppressive functions and are currently considered a very important cell type affecting tumor immunity. This study observed changes in MDSC frequency in peripheral blood before and after GSM–TACE to evaluate the effect on the immune function of HCC patients.Methods: Eight patients diagnosed with HCC underwent GSM–TACE treatment in the Hepatobiliary Interventional Department of Beijing Tsinghua Chang Gung Hospital, Beijing, China;we followed up with the patients over a period of 30 days post-surgery. We used flow cytometry(FCM) to quantify the frequency of MDSCs in peripheral blood before TACE, 10 days after surgery and 30 days after surgery.Results: MDSC frequency after GSM–TACE had a significant downward trend. Pre-TACE, it was 30.73% ? 11.93%,decreasing to 18.60% ? 11.37% at 10 days after operation. This decrease was not statistically significant(P > 0.05). MDSC frequency was even lower 30 days after TACE(7.63% ? 7.32%) than at 10 days after TACE(P < 0.05), and there was a significant difference compared with pre-TACE(P < 0.001). We evaluated tumor response at 30 days after GSM–TACE according to the Modified Response Evaluation Criteria in Solid Tumors(mRECIST), and all eight patients showed partial response(PR).Conclusion: Our results confirmed that GSM–TACE was beneficial for improving anti-tumor immunity in the treatment of HCC.Yuanxun Yue Zhizhong Ren Ying Liu Yuewei Zhang 2019Journal of Interventional Medicine2019,2,1:2
11A flexible BiFeO_(3)-based ferroelectric tunnel junction memristor for neuromorphic computing显示文摘Ferroelectric tunnel junctions(FTJs)as the artificial synaptic devices have been considered promising for constructing brain-inspired neuromorphic computing systems.However,the memristive synapses based on the flexible FTJs have been rarely studied.Here,we report a flexible FTJ memristor grown on a mica substrate,which consists of an ultrathin ferroelectric barrier of BiFeO_(3),a semiconducting layer of ZnO,and an electrode of SrRuO_(3).The obtained flexible FTJ memristor exhibits stable voltage-tuned multistates,and the resistive switchings are robust after 10^(3) bending cycles.The capability of the FTJ as a flexible synaptic device is demonstrated by the functionality of the spike-timing-dependent plasticity with bending,and the accurate conductance manipulation with small nonlinearity(-0.24)and low cycle-to-cycle variation(1.77%)is also realized.Especially,artificial neural network simulations based on experimental device behaviors reveal that the high recognition accuracies up to 92.8%and 86.2%are obtained for handwritten digits and images,respectively,which are close to the performances for ideal memristors.This work highlights the potential applications of FTJ as flexible electronics for data storage and processing.Haoyang Sun Zhen Luo Chuanchuan Liu Chao Ma Zijian Wang Yuewei Yin Xiaoguang Li 2022Journal of Materiomics2022,8,1:2
12The littoral zone in the Three Gorges Reservoir, China: challenges and opportunities 显示文摘YUAN Xingzhong ZHANG Yuewei LIU Hong 2013Environmental Science and Pollution Research2013,20,10:1
13Locally Optimum Detection for Barni's Multiplicative Watermarking in DWT Domain显示文摘Wang Jinwei Liu Guangjie Dai Yuewei 0,,01:1
14The littoral zone in the Three Gorges Reservoir, China Challenges and opportunities显示文摘Yuan Xingzhong Zhang Yuewei Liu Hong 2013Environmental Sci- ence and Pollution Research2013,20,10:1
15The littoral zone in the Three Gorges Reservoir, China: challenges and opportunities 显示文摘YUAN Xingzhong ZHANG Yuewei LIU Hong 2013Environmental Science and Pollution Research2013,20,10:1
16Locally optimum detec-tion for Barni' s muhiplicative watermarking in DWT domain 显示文摘Wang Jinwei Liu Guangjie Da Yuewei 2008Sig-nal processing2008,88,:1
17Simultaneous nested modeling from the synoptic scale to the LES scale for wind energy applications显示文摘Yubao Liu Tom Warner Yuewei Liu Claire Vincent Wanli Wu Bill Mahoney Scott Swerdlin Keith Parks Jennifer Boehnert 2011Journal of Wind Engineering & Industrial Aerodynamics2011,,4:1
18Locally opti- mum detection for Barni' s mtdtiplicative watermarking in DWT domain显示文摘Wang Jinwei Liu Guangjie Dai Yuewei 2008Signal Processing2008,88,1:1
19COMPARISONS OF RAY-TRACING AND PARABOLIC EQUATION METHODS FOR THE LARGE-SCALE COMPLEX ELECTROMAGNETIC ENVIRONMENT SIMULATIONS显示文摘It is important for the wireless communication field to conduct research on large-scale complex electromagnetic environment(CEME)simulation.There exist many models for computing CEME simulation,including empirical models,half-empirical or halfdeterministic models and deterministic models.Most of these models cannot obtain satisfactory results due to the limitation of the capacity of computers.The ray tracing(RT)and parabolic equation(PE)methods are very suitable for large-scale CEME simulation.Based on the introduction of RT and PE,qualitative comparisons of the two methods are analyzed in view of algorithm theory,the category of the model,solution to the model and the application field,and then four specific indices are focused on to analyze the computational complexity,accuracy,speed and parallelism in details.The numerical experiments are presented by the three-dimensional(3D)RT method employing the software of Wireless InSite(WI)and a quasi-3DPE method using the sliced method.Although both RT and PE methods can achieve high speedup using coarse-grained parallel computing,the experimental results indicate that the PE method can obtain a higher speed than the RT method,and the two methods can acquire an approximate precision.A hybrid procedure using both RT and PE methods can obtain a better result for solving CEME problems.YUEWEI SHEN LIN ZHANG DENGKUN LIU YINGNIAN WU LAN MU ALPH CHUNTSINGER 2012International Journal of Modeling, Simulation, and Scientific Computing2012,3,2:1
20Landsat 8 OLI image based terrestrial water extraction from heterogeneous backgrounds using a reflectance homogenization approach显示文摘Yuhao Yang Yongxue Liu Minxi Zhou Siyu Zhang Wenfeng Zhan Chao Sun Yuewei Duan 2015Remote Sensing of Environment2015,,:1
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