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An SOR Implicit Time-accurate Scheme in Calculating Unsteady Flows

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Chinese Journal of Aeronautics 2007年第3期20卷 202-209页

作者： li yue-jun YAN Chao School of Aeronautic Science and Engineering Beijing University of 4eronautics andAstronautics Beijing 100083 China

A new time-accurate marching scheme for unsteady flow calculations is proposed in the present work. This method is the combination of classical Successive Over-Relaxation （SOR） iteration method and Jacobian matrix diagonally dominant splitting method of LUSGS. One advantage of this algorithm is the second-order accuracy because of no factorization error. Another advantage is the low computational cost because the Jacobian matrices and fluxes are only calculated once in each physical time step. And, the SOR algorithm has better convergence property than Gauss-Seidel. To investigate its accuracy and convergency, several unsteady flow computational tests are carded out by using the proposed SOR algorithm. Roe＇s FDS scheme is used to discritize the inviscid flux terms. Unsteady computational results of SOR are compared with the experiment results and those of Gauss-Seidel, Results reveal that the numerical results agree well with the experimental data and the second-order accuracy can be obtained as the Gauss-Seidel for unsteady flow computations. The impact of SOR factor is investigated for unsteady computations by using different SOR factors in this algorithm to simulate each computational test. Different numbers of inner iterations are needed to converge to the same criterion for different SOR factors and optimal choice of SOR factor can improve the computational efficiency greatly.

关键词： unsteady flow SOR algorithm SOR factor Gauss-Seidel

Multistage soft decision equalization technique for MIMO systems in frequency selective channels

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 7-11页

作者： YU Jiang li Xiao-jun yue Guang-xin Digital Communications and Networking Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China

This article proposes a multistage soft decision equalization （SDE） technique for block transmission over frequency selective multi-input multi-output （MIMO） channels. Using the Toeplitz structure, the general signal model can be converted into a series of small-sized sub-signal models. For each sub-signal model, soft interference cancellation （SIC） is used firstly to remove partial effects of interfering symbols, then max-log-map sphere decoder is performed to get the desired a posteriori information. Simulation shows that with lower complexity the proposed method outperforms the probability data association SDE and the Schnorr-Euchner sphere decoder.

关键词： sphere decoder SDE

Sijunzi Decoction Inhibits Stemness by Suppressingβ-Catenin Transcriptional Activity in Gastric Cancer Cells

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Chinese Journal of Integrative Medicine 2022年第8期28卷 702-710页

作者： li yue-jun liAO lin-li liU Pei TANG Ping WANG Hong PENG Qing-hua Department of Oncology the Third Affiliated Hospital of Hunan University of Chinese MedicineZhuzhou412000Hunan ProvinceChina Department of Oncology the First Affiliated Hospital of Hunan College of Traditional Chinese MedicineZhuzhou412000Hunan ProvinceChina Hunan Provincial Key Laboratory for the Prevention and Treatment of Ophthalmology and Otolaryngology Diseases with Traditional Chinese Medicine Hunan University of Chinese MedicineChangsha410208China

Objective:To investigate a previously uncharacterized function of Sijunzi Decoction(SJZD)in inhibition of gastric cancer stem cells(GCSCs).Methods:MKN74 and MKN45,two CD44 positive gastric cancer cell lines with stem cell properties were *** cells were divided into 2 *** group was treated with SJZD(1-5 mg/mL)for indicated time(48 h-14 days).The control group was treated with equal volume of phosphate buffered *** Counting Assay Kit-8 were used to measure cell *** colony formation and GCSCs marker expression were performed to determine GCSCs *** fractionation and chromatin immunoprecipitation assays were used to assess the distribution and DNA-binding activity of β-catenin after SJZD treatment,***:SJZD treatment repressed cell growth and induced apoptosis in MKN74 and MKN45 cell lines(P<0.05).Moreover,SJZD dramatically inhibited formation of spheroid colony and expression of GCSC markers in GC cells(P<0.05).Mechanistically,SJZD reduced nuclear accumulation and DNA binding activity ofβ-catenin(P<0.05),the key regulator for maintaining CSC ***:SJZD inhibits GCSCs by attenuating the transcriptional activity of β-catenin.

关键词： Sijunzi Decoction Chinese medicine gastric cancer cancer stem cells β-catenin

Targets capture by distributed active swarms via bio-inspired reinforcement learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 206-217页

作者： Kun Xu yue li jun Sun Shuyuan Du Xinpeng Di Yuguang Yang Bo li Institute of Biomechanics and Medical Engineering Applied Mechanics LaboratoryDepartment of Engineering MechanicsTsinghua UniversityBeijing 100084China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Shanghai Aerospace Control Technology Institute Shanghai 201109China Shanghai Key Laboratory of Aerospace Intelligent Control Technology Shanghai 201109China College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Natural swarms arranged from cells to herds are usually decentralized but display intriguing collective intelligence in coordinating individuals across large scales to efficiently achieve their common *** from nature may provide new strategies for controlling collective dynamics of synthetic swarms to accomplish specific ***,we present a bioinspired computational framework that steers distributed active swarms to collectively capture and merge targets via reinforcement *** exploit collective milling structures of natural herds to cage the targets,and adopt a switching control policy inspired by sperms’chiral dynamics to optimize the trajectories of individuals,through which the active swarms can selforganize to enclose single or multiple distant targets in a dynamical,adaptive and scalable *** exists a critical swarm size,beyond which the excessive competition between agents would generate large mechanical forces,leading to capture instability but enabling the transition from short-distance to long-distance merging capture of multiple *** work provides physical insights into distributed active swarms and could offer a multilevel,decentralized strategy toward controlling swarm robotics in wide applications such as bio-medical devices,machine immunity,and target clearance.

关键词： swarm intelligence robotics multi-tasks artificial intelligence bionics

The Hydration of Blended Cement at Low W/B Ratio

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Journal of Wuhan University of Technology(Materials Science) 2003年第4期18卷 72-75页

作者：胡曙光 Wuhan University of Technology

The hydration process,hydration product and hydration heat of blended cement paste mixed with mineral admixture and expansive agent at low W/B ratio are studied by XRD,thermo analysis,and calorimetry instrument,and they were compared with those of pure cement *** results show that pure cement and blended cement at low W/B ratio have the same types of hydration products,but their respective amounts of hydration products of various blended cements at same ages and the variation law of the amount of same hydration products with ages are different;The joint effect of tumefaction of gel-ettringite due to water absorption and the expansive pressure on the pore and rift caused by the crystalloid ettringite is the impetus of the volume expansion of cement paste,and the former effect is much greater than the latter one.

关键词： hydration blended cement low W/B ratio expansion mechanism

Dynamic analysis of multibodies system with a floating base for rolling of ro-ro ship caused by wave and slip of heavy load

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Journal of Marine Science and Application 2003年第2期2卷 17-24页

作者： Qing Shen yue li and Xu-jun Chen PLA University of Science and Technology The Engineering Institute of Engineer Corps Nanjing China (GRID:grid.440614.3)

Common effect of wave and slip of internal heavy load will make rolling of the roll-on ship serious. This is one of the important reasons for overturn of ro-ro ships. The multibodies System with a floating base is composed of ro-ro ship and slipping heavy load. This paper takes the rolling angle of the ship and the transverse displacement of the heavy load on desk as two freedoms. Making use of analysis of apparent gravitation and apparent buoyancy, the wave rolling moment is derived. By use of dynamic method of multibodies system with a floating base, dynamic equations of the system are established. Taking a certain channel ferry as an example, a set of numerical calculation have been carried out for rolling response of the ship and displacement response of the slipping heavy load under common effect of synchro-slipping heavy loads and wave.

关键词： ro-ro ship floating base multibodies system dynamics

Relative humidity-dependent evolution of molecular composition ofα-pinene secondary organic aerosol upon heterogeneous oxidation by hydroxyl radicals

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Journal of Environmental Sciences 2025年第2期148卷 210-220页

作者： Wei Wang Chenxi li Huayun Xiao Ziyue li yue Zhao School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Heterogeneous oxidation by gas-phase oxidants is an important chemical transformation pathway of secondary organic aerosol(SOA)and plays an important role in controlling the abundance,properties,as well as climate and health impacts of ***,our knowledge on this heterogeneous chemistry remains *** this study,the heterogeneous oxidation ofα-pinene ozonolysis SOA by hydroxyl(OH)radicals was investigated under both low and high relative humidity(RH)conditions,with an emphasis on the evolution of molecular composition of SOA and its RH *** is found that the heterogeneous oxidation of SOA at an OH exposure level equivalent to 12 hr of atmospheric aging leads to particle mass loss of 60%at 25%RH and 95%at 90%*** heterogeneous oxidation strongly changes the molecular composition of *** dimer-to-monomer signal ratios increase dramatically with rising OH exposure,in particular under high RH conditions,suggesting that aerosol water stimulates the reaction of monomers with OH radicals more than that of *** addition,the typical SOA tracer compounds such as pinic acid,pinonic acid,hydroxy pinonic acid and dimer esters(e.g.,C17H26O8 and C19H28O7)have lifetimes of several hours against heterogeneous OH oxidation under typical atmospheric conditions,which highlights the need for the consideration of their heterogeneous loss in the estimation of monoterpene SOA concentrations using tracer-based *** study sheds lights on the heterogeneous oxidation chemistry ofmonoterpene SOA andwould help to understand their evolution and impacts in the atmosphere.

关键词： Secondary organic aerosol(SOA) Heterogeneous oxidation Chemical transformation Molecular composition Aerosol water

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锇胺分子氢配合物的研究进展

无机化学学报 2000年第2期16卷 179-184页

作者：杨频岳丽君山西大学分子科学研究所太原030006

由于锇胺分子氢配合物中有特殊的键M(η2 H2 )和特殊的配体分子氢的存在 ,故而具有丰富的取代化学和特殊的光谱性质。在无机化学、配位化学、生物、医药等方面都有极为广阔的应用前景。

关键词：锇胺分子氢配合物锇胺二氢化物核磁探针抗癌药

Research on the hazards of gas leakage and explosion in a full-scale residential building

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Defence Technology(防务技术) 2025年第1期43卷 168-181页

作者： Chengjun yue li Chen Zhan li Bin Feng Ruizhi Xu Engineering Research Center of Safety and Protection of Explosion&Impact of Ministry of Education Southeast UniversityNanjing 211189China

The gas explosion in residential building has always been a highly concerned *** in homogeneous mixtures have been extensively ***,mixtures are often inhomogeneous in the practical scenarios due to the differences in the densities of methane and *** order to investigate the effects of gas explosions in inhomogeneous mixtures,experimental studies involving gas leakage and explosion are conducted in a full-scale residential building to reproduce the process of gas *** fitting the dimensionless buoyancy as a function of dimensionless height and dimensionless time,a distribution model of gas in large-scale spaces is established,and the mechanism of inhomogeneous distribution of methane is also be ***,the stratified reconstruction method(SRM)is introduced for efficiently setting up inhomogeneous concentration fields in *** simulation results highlight that for the internal overpressure,the distribution of methane has no effect on the first overpressure peak(ΔP1),while it significantly influences the subsequent overpressure peak(ΔP2),and the maximum difference between the overpressure of homogeneous and inhomogeneous distribution is174.3%.Moreover,the initial concentration distribution also has a certain impact on the external overpressure.

关键词： Methane distribution Inhomogeneous mixture Gradient layer Gas explosion Explosive simulation