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two-step two-Sweep Modulus-Based Matrix Splitting Iteration Method for Linear Complementarity Problems

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Numerical Mathematics(Theory,Methods and Applications) 2022年第3期15卷 592-619页

作者： Maryam Bashirizadeh Masoud Hajarian Department Applied Mathematics Faculty of Mathematical SciencesShahid Beheshti UniversityTehranIran

Linear complementarity problems have drawn considerable attention in recent years due to their wide *** this article,we introduce the two-step two-sweep modulus-based matrix splitting(TSTM)iteration method and two-sweep modulus-based matrix splitting type II(TM II)iteration method which are a combination of the two-step modulus-based method and the two-sweep modulus-based method,as two more effective ways to solve the linear complementarity *** convergence behavior of these methods is discussed when the system matrix is either a positive-definite or an H+-***,numerical experiments are given to show the efficiency of our proposed methods.

关键词： Linear complementarity problem modulus-based method two-step two sweep H+-matrix convergence

two-step Estimation for Longitudinal Data When the Working Correlation Matrix is a Linear Combination of Some Known Matrices

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Acta Mathematicae Applicatae Sinica 2019年第2期35卷 264-273页

作者： Yu-ling LI Wei GAO Man-Lai TANG Shu-rong ZHENG Key Laboratory for Applied Statistics of MOE School of Mathematics and StatisticsNortheast Normal University School of Applied Mathematics Beijing Normal University Department of Mathematics and Statistics Hang Seng Management College

The generalized estimating equations(GEE) approach is perhaps one of the most widely used methods for longitudinal data analysis. While the GEE method guarantees the consistency of its estimators under working correlation structure misspecification, the corresponding efficiency can be severely affected. In this paper, we propose a new two-step estimation method in which the correlation matrix is assumed to be a linear combination of some known working matrices. Asymptotic properties of the new estimators are *** studies are conducted to examine the performance of the proposed estimators. We illustrate the methodology with an epileptic data set.

关键词： generalized estimating equations longitudinal data quadratic inference functions quasi-likelihood two-step estimation

two-step unsymmetrical quantum key distribution protocol using GHZ triplet states

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The Journal of China Universities of Posts and Telecommunications 2009年第3期16卷 114-121页

作者： HUANG Peng LIU Ye ZHOU Nan-run ZENG Gui-hua Department of Electronic Information EngIneering Nanchang University Nanchang 330031 China State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 China

The security, efficiency, transmission distance and error rate are important parameters of a quantum key distribution scheme. In this article, the former two parameters are focused on. To reach high efficiency, an unsymmetrical quantum key distribution scheme that employs Greenberger-Horne-Zeilinger （GHZ） triplet states and dense coding mechanism is proposed, in which a GHZ triplet state can be used to share two bits of classical information. The proposed scheme can be employed in a noisy or lossy quantum channel. In addition, a general approach to security analysis against general individual attacks is presented.

关键词： two-step tmsymmetrical quantum key distribution GHZ triplet states

Novel two-step CdS deposition strategy to improve the performance of Cu2ZnSn(S,Se)4 solar cell

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Journal of Energy Chemistry 2020年第3期29卷 77-82页

作者： Lifang Teng Junye Tong Gang Wang Lingling Wang Liping Chen Shaotong Wang Yinglin Wang Daocheng Pan Xintong Zhang Yichun Liu Center for Advanced Optoelectronic Functional Materials Research and Key Laboratory of UV-Emitting Materials and Technology of Ministry of EducationNortheast Normal UniversityChangchun 130024JilinChina State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022JilinChina

Kesterite Cu2ZnSn(S,Se)4(CZTSSe)solar cells have drawn worldwide attention for their promising photovoltaics performance and earth-abundant element composition,yet the record efficiency of this type of device is still far lower than its theoretical conversion *** band alignment and severe non-radiative recombination at CZTSSe/CdS heterojunction interfaces are the major causes limiting the current/voltage output and overall device ***,we propose a novel two-step CdS deposition strategy to improve the quality of CZTSSe/CdS heterojunction interface and thereby improve the performance of CZTSSe solar *** two-step strategy includes firstly pre-deposits CdS thin layer on CZTSSe absorber layer by chemical bath deposition(CBD),followed with a mild heat treatment to facilitate element inter-diffusion,and secondly deposits an appropriate thickness of CdS layer by CBD to cover the whole surface of pre-deposited CdS and CZTSSe *** solar energy conversion efficiency of CZTSSe solar cells with two-step deposited CdS layer approaches to 8.76%(with an active area of about 0.19 cm2),which shows an encouraging improvement of over 87.98%or 30.16%compared to the devices with traditional CBD-deposited CdS layer without and with the mild annealing process,*** performance enhancement by the two-step CdS deposition is attributed to the formation of more favorable band alignment at CZTSSe/CdS interface as well as the effective decrease in interfacial recombination paths on the basis of material and device *** two-step CdS deposition strategy is simple but effective,and should have large room to improve the quality of CZTSSe/CdS heterojunction interface and further lift up the conversion efficiency of CZTSSe solar cells.

关键词： Kesterite Solar cell CdS two-step deposition Heterojunction interface

A Plant Immune Receptor Adopts a two-step Recognition Mechanism to Enhance Viral Effector Perception

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Molecular Plant 2019年第2期12卷 248-262页

作者： Jia Li Haining Huang Min Zhu Shen Huang Wenhua Zhang Savithramma P. Dinesh-Kumar Xiaorong Tao Department of Plant Pathology Nanjing Agricultural University Nanjing 210095 P. R. China College of Life Science Nanjing Agricultural University Nanjing 210095 P. R. China Department of Plant Biology and The Genome Center College of Biological Sciences University of California Davis CA USA

Plant intracellular nucleotide binding leucine-rich repeat (NLR) immune receptors play critical roles in pathoge n surveillance. Most plant NLRs characterized so far were found to use a single domain/sensor to recognize pathogen effectors. Here we report that the Sw-5b NLR immune receptor uses two distinct domains to detect the viral movement protein NSm encoded by tospovirus. In addition to its leucine-rich repeat (LRR) domain that has been previously reported, the N-terminal Solanaceae domain (SD) of Sw- 5b also interacts with NSm and a conserved 21-amino-acid region of NSm (NSm^21). The specific interaction between Sw-5b SD and NSm is required for releasing the inhibitory effect of coiled-coil domain on the NBARC- LRR region. Furthermore, we found that the binding of NSm affects the nucleotide binding activity of the NB-ARC-LRR in vitro, while Sw-5b NB-ARC-LRR is activated only when NSm and NSm^21 levels are high. Interestingly, Sw-5b SD could significantly enhanee the ability of the NB-ARC-LRR to detect low levels of NSm effector and facilitate its activation and induction of defense response. An Sw-5b SD mutant that is disrupted in NSm recognition failed to enhance the ability of the NB-ARC-LRR to sense low levels of NSm and NSm^21 . Taken together, our results suggest that Sw-5b SD functions as an extra sensor and the NB-ARC-LRR as an activator, and that Sw-5b NLR adopts a two-step recog nition mechanism to enhance viral effector perception.

关键词： plant innate immunity nucleotide binding leucine-rich repeat (NLR) immune receptors Solanaceae domain (SD) pathogen perception two-step recognition defense response

A two-step quantum secure direct communication protocol with hyperentanglement

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Chinese Physics B 2011年第10期20卷 66-70页

作者：顾斌黄余改方夏张成义 College of Mathematics and Physics Nanjing University of Information Science and Technology The Photonic Technology Laboratory Nanjing University of Information Science and Technology Jiangsu Institute of Education

We propose a two-step quantum secure direct communication （QSDC） protocol with hyperentanglement in both the spatial-mode and the polarization degrees of freedom of photon pairs which can in principle be produced with a beta barium borate crystal. The secret message can be encoded on the photon pairs with unitary operations in these two degrees of freedom independently. This QSDC protocol has a higher capacity than the original two-step QSDC protocol as each photon pair can carry 4 bits of information. Compared with the QSDC protocol based on hyperdense coding, this QSDC protocol has the immunity to Trojan horse attack strategies with the process for determining the number of the photons in each quantum signal as it is a one-way quantum communication protocol.

关键词： quantum secure direct communication two-step hyperentanglement high capacity

A Novel two-step Frequency Offset Estimator for OFDM

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Journal of Donghua University(English Edition) 2008年第6期25卷 621-625页

作者：吴赟蒋新华许武军 College of Information Science & Technology Donghua University Shanghai Institute of Space Power Source

Based on an orthogonal frequency division multiplexing(OFDM) training symbol with L identical parts, a novel carrier frequency offset (CFO) estimator is proposed for OFDM systems. The CFO is estimated in two steps, fine estimate and coarse estimate. In the first step, the fine estimation is performed based on the principle of minimum variance. However, the fine estimation has ambiguity since its estimate range is limited. In the second step, the coarse estimation is obtained, which results in a larger estimate range but less precision. Using the coarse estimation, the ambiguity of fine estimation is resolved. To fully use the correlation among L identical parts, the fine estimation resolved the ambiguity and the coarse estimation are optimally combined to obtain the final estimation. Furthermore, the estimation variance of the proposed method is derived. Simulation results demonstrate that the novel two-step estimator outperforms the conventional two-step estimator in terms of estimate performance and computational complexity.

关键词： frequency offset estimation OFDM trainingsymbol two-step

two-step MECHANISM IN HETEROGENEOUS CATALYSIS AND DYNAMIC ANALYSIS

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Chinese Journal of Chemical Engineering 1992年第1期 103-107页

作者：陈诵英彭少逸杨争平 Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 Shanxi

Recent development of the dynamic analysis technique has made it possible to measure separately kinetic parameters of a catalytic reaction as well as to study the effect of catalyst preparation parameters. But its application is still limned to first-order reaction. This work is aimed to demonstrate in some detail that,by comparison of the reaction rate expressions with the two-step mechanism used in catalytic kinetics and dynamic analysis, these methods can be extended to non-first-order reaction, and the kinetic parameters measured by dynamic techniques are interpreted for different reaction mechanisms.

关键词： two-step mechanism dynamic analysis heterogeneous catalysis

Preoperative selective portal vein embolization in two-step hepatectomy for hepatocellular carcinoma in injured livers: a preliminary report

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Hepatobiliary & Pancreatic Diseases International 2003年第2期2卷 532-536页

作者： Wu Ji Wu-Hong Liu Kuan-Sheng Ma Xiang-Tian Wang Zhen-Ping He Jia-Hong Dong Jie-Shou Li Department of General Surgery Kunming General Hospital of Chengdu PLA Command Kunming 650032 China. jiwusky@***

OBJECTIVE: To study the effect of preoperative selective portal vein embolization (SPVE) in thetwo-step hepatectomy for patients with primary hepatocellular carcinoma (HCC) in injured ***: Twenty-six patients with HCC and cirrhosis who were not suitable for curative hepatectomywere treated by ultrasound-guided percutaneous transhepatic SPVE with a fine needle. The success rate,side-effects and complications of SPVE, serial changes of hepatic lobe volume and rate of two-step curativehepatectomy after SPVE were ***: SPVE was performed in 24 patients (92.3%). In patients whose right portal vein brancheswere embolized, the right hepatic volume decreased but the left hepatic volume increased gradually. Theratio of the right hepatic volume to the total hepatic volume decreased from 64.O% before SPVE to 60.8%after 1 week, 55.1% after 2 weeks and 52.7% after 3 weeks, respectively. The side-effects includeddifferent degree of pain in the liver quandrant (17 patients), lower fever (9), and nausea and vomiting(7). The levels of aspartate alanine transaminase (AST), alanine transaminase (ALT) and total bilirubin(TBIL) increased after SPVE, but returned to the preoperative levels in 1 week. After 2-4 weeks,two-step curative hepatectomy for HCC was performed in 13 patients (54.2%).CONCLUSIONS: Ultrasound-guided percutaneous transhepatic SPVE with a fine needle is feasible andsafe. It can extend the indications of curative hepatectomy for HCC in injured livers, and increase thesafety of two-step hepatectomy.

关键词： portal vein embolization two-step hepatectomy primary hepatocellular careinoma cirrhosis