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Research on the influences of motion characteristics of jetting projectile charge under water

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Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： xing Chen Yong-gang lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater *** paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in *** findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying *** the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the *** optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in *** density plays a crucial role in the velocity decay pattern of the JPC during *** with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are ***,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge ***,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

Aerodynamic Characteristics of the Crest with Membrane Attachment on Cretaceous Pterodactyloid Nyctosaurus

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Acta Geologica Sinica(English Edition) 2009年第1期83卷 25-32页

作者： xing Lida WU Jianghao lu yi Lü Junchang JI Qiang Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China School of Transportation Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The Nyctosaurus specimen K J1 was reconstructed under the hypothesis that there is a membrane attached to the crest; the so-called headsail crest. The aerodynamic forces and moment acting on the headsail crest were analyzed. It was shown that K J1 might adjust the angle of the headsail crest relative to the air current as one way to generate thrust （one of the aerodynamic forces, used to overcome body drag in forward flight） and that the magnitude of the thrust and moment could vary with the gesture angle and the relative location between the aerodynamic center of the headsail crest and body＇s center of gravity. Three scenarios were tested for comparison： the crest with membrane attachment, the crest without membrane attachment and the absence of a cranial crest. It was shown that the aerodynamic characteristics （increasing, maintaining and decreasing thrusts and moment） would have almost disappear in flight for the crest without membrane attachment and was non-existent without the cranial crest. It is suggested from aerodynamics evidence alone that Nyctosaurus specimen KJ1 had a membrane attached to the crest and used this reconstructed form for auxiliary flight control.

关键词： aerodynamic forces and moment flight dynamic Nyctosaurus headsail crest

Association between interleukin-10 genetic polymorphisms and risk of primary open angle glaucoma in a Chinese Han population: a case-control study

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International Journal of Ophthalmology(English edition) 2019年第10期12卷 1605-1611页

作者： yi-Hui Zhang yi-Qiao xing Zhen Chen Xiao-Cheng Ma Qiang lu Department of Ophthalmology Renmin Hospital of WuhanUniversityWuhan430060Hubei PronvinceChina Ophthalmology Department of Inner Mongolia People’sHospital Hohhot010017Inner Mongolia AutonomousRegionChina

AIM: To investigate the association between interleukin-10(IL-10) genetic polymorphisms and risk of POAG through a case-control study in a Han population of ***: A total of 210 patients with POAG and 420 normal subjects were recruited during the period from Dec. 2013 to Dec. 2016. The IL-10-1082 A>G(rs1800870),-819 T>C(rs1800871) and-592 C>A(rs1800872) polymorphisms were determined using iPlex GOLD SNP genotyping analysis(the SequenomMassARRAY? System, Sequenom, San Diego, USA). The association between IL-10-1082 A>G(rs1800870),-819 T>C(rs1800871), and-592 C>A(rs1800872) polymorphisms and risk of POAG was assessed by singlelogistic regression ***: We observed that those carrying the CC genotype of rs1800871 was associated with an increased risk of POAG when compared with those harboring the TT genotype(OR=1.84, 95%CI=1.01-3.38). Those with AA genotype of rs1800872 had a 10.62 fold risk of POAG in comparison to the CC genotype(OR=10.62, 95%CI, 3.41-33.09). A completely linkage disequilibrium was found between IL-10 rs1800871-rs1800872(D’=1.00, r2=0.16). The A-C-A(OR=2.60, 95%CI, 1.48-4.58) and G-T-A(OR=2.34, 95%CI, 1.42-3.86) haplotypes were associated with an increased risk of POAG, while the A-T-C haplotype showed a decreased risk of POAG(OR=0.63, 95%CI, 0.49-0.81). CONCluSION: Our data suggest that IL-10 rs1800871 and rs1800872 can be predictive factors for the pathogenesis of POAG in the Chinese population.

关键词： primary open angle glaucoma IL-10 polymorphism haplotype

Searching for γ-ray emission from LOTAAS pulsars

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Research in Astronomy and Astrophysics 2021年第3期21卷 61-68页

作者： Qi-Wei lu Zhong-Xiang Wang yi xing Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of the Chinese Academy of Sciences Beijing 100049China Department of Astronomy Yunnan UniversityKunming 650091China

The LOw-Frequency ARray(LOFAR)has recently conducted a survey(LOFAR Tied-Array Allsky Survey;LOTAAS)for pulsars in the Northern hemisphere that resulted in discoveries of 73 new *** the purpose of studying the properties of these pulsars,we search for theirγ-ray counterparts using the all-sky survey data obtained with the Large Area Telescope(LAT)onboard the Fermi Gamma-Ray Space Telescope(Fermi).We analyze the LAT data for 70 LOTAAS pulsars(excluding two millisecond pulsars and one with the longest known spin period of 23.5 s).We find one candidate counterpart to PSR J1017+30,which should be searched for theγ-ray pulsation signal once its timing solution is *** other LOTAAS pulsars,we derive their 0.3-500 GeV flux upper *** order to compare the LOTAAS pulsars with the knownγ-ray pulsars,we also derive the 0.3-500 GeVγ-ray fluxes for 112 of the latter contained in the Fermi LAT fourth source *** on the properties of theγ-ray pulsars,we derive upper limits on the spin-down luminosities of the LOTAAS *** upper limits are not very constraining but help suggest that most of the LOTAAS pulsars probably haveluminosities and are not expected to be detectable with Fermi LAT.

关键词： stars:pulsars stars:neutron gamma rays:stars

Exact Boundary Controllability of Weak Solutions for a Kind of First Order Hyperbolic System——The Constructive Method

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Chinese Annals of Mathematics,Series B 2021年第5期42卷 643-676页

作者： xing lu Tatsien LI School of Mathematics Southeast UniversityNanjing 211189China School of Mathematical Sciences Fudan UniversityShanghai 200433China Shanghai Key Laboratory for Contemporary Applied Mathematic Nonlinear Mathematical Modeling and Methods Laboratory

In this paper the authors first present the definition and some properties of weak solutions to 1-D first order linear hyperbolic systems. Then they show that the constructive method with modular structure originally given in the framework of classical solutions is still very powerful and effective in the framework of weak solutions to prove the exact boundary(null) controllability and the exact boundary observability for first order hyperbolic systems.

关键词： First order linear hyperbolic system Exact boundary controllability Exact boundary observability Constructive method

Exact Boundary Controllability of Weak Solutions for a Kind of First Order Hyperbolic System——the HUM Method

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Chinese Annals of Mathematics,Series B 2022年第1期43卷 1-16页

作者： xing lu Tatsien LI School of Mathematics Southeast UniversityNanjing 211189China School of Mathematical Sciences Fudan UniversityShanghai 200433China Shanghai Key Laboratory for Contemporary Applied Mathematics Fudan University Nonlinear Mathematical Modeling and Methods Laboratory Fudan University

The exact boundary controllability and the exact boundary observability for the 1-D first order linear hyperbolic system were studied by the constructive method in the framework of weak solutions in the work[lu,*** Li,T.T.,Exact boundary con-trollability of weak solutions for a kind of first order hyperbolic system—the constructive method,***.B,42(5),2021,643-676].In this paper,in order to study these problems from the viewpoint of duality,the authors establish a complete the-ory on the HUM method and give its applications to first order hyperbolic ***,a deeper relationship between the controllability and the observability can be ***,at the end of the paper,a comparison will be made between these two methods.

关键词： First order linear hyperbolic system Exact boundary controllability The HUM method

Laser additive manufacturing of laminated bulk metallic glass composite with desired strength-ductility combination

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Journal of Materials Science & Technology 2023年第16期147卷 68-76页

作者： Xiangcheng Cui Weihua Hu xing lu Yunzhuo lu School of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116028China

Introducing ductile crystalline dendrites into a glassy matrix to produce bulk metallic glass composites(BMGCs)is an effective way to improve the poor ductility of bulk metallic glasses(BMGs).However,the presence of soft crystalline phases tends to decrease the strength and causes the strength-ductility ***,relying on the flexible laser additive manufacturing(LAM)technique that allows the composition tailoring of each layer,we successfully fabricate a lamellated Zr-based BMGC constructed by the alternating superimposition of soft and hard *** lamellated BMGC shows an exceptional combination of yield strength(∼1.2 GPa)and ductility(∼5%).Such enhanced strength-ductility synergy is attributed to the asynchronous deformation at two scales,i.e.,inter-laminar and intra-laminar,and the unique dual-scale Ta particles that uniformly distribute on the amorphous *** lamellated structure design motif,enabled by the flexible LAM technology,provides a new window for the development of high-performance *** is also applicable to the synergistic enhancement of strength and plasticity of other brittle metallic materials.

关键词： Bulk metallic glass composite Additive manufacturing Mechanical property Lamellated Strength-ductility synergy

Shadow obstacle model for realistic corner-turning behavior in crowd simulation

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Frontiers of Information Technology & Electronic Engineering 2016年第3期17卷 200-211页

作者： Gao-qi HE yi JIN Qi CHEN Zhen LIU Wen-hui YUE xing-jian lu Department of Computer Science and Engineering East China University of Science and Technology Shanghai 200237 China MOE Key Laboratory of Geographic Information Science East China Normal University Shanghai 200241 China State Key Laboratory of Virtual Reality Technology and Systems Beihang University Beijing 100191 China College of Information Science and Technology Ningbo University Ningbo 315211 China

This paper describes a novel model known as the shadow obstacle model to generate a realistic comer-tuming behavior in crowd simulation. The motivation for this model comes from the observation that people tend to choose a safer route rather than a shorter one when turning a comer. To calculate a safer route, an optimization method is proposed to generate the corner-turning rule that maximizes the viewing range for the agents. By combining psychological and physical forces together, a full crowd simulation framework is established to provide a more realistic crowd simulation. We demonstrate that our model produces a more realistic comer-turning behavior by comparison with real data obtained from the experiments. Finally, we per- form parameter analysis to show the believability of our model through a series of experiments.

关键词： Comer-turning behavior Crowd simulation Safety awareness Rule-based model

Nanocarrier-mediated siRNA delivery:a new approach for the treatment of traumatic brain injury-related Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2538-2555页

作者： Jie Jin Huajing Zhang Qianying lu Linqiang Tian Sanqiao Yao Feng Lai Yangfan Liang Chuanchuan Liu Yujia lu Sijia Tian Yanmei Zhao Wenjie Ren Institute of Disaster and Emergency Medicine Tianjin UniversityTianjinChina Key Laboratory for Disaster Medicine Technology TianjinChina Henan Medical Key Laboratory for Research of Trauma and Orthopedics The Third Affiliated Hospital of Xinxiang Medical UniversityXinxiangHenan ProvinceChina Clinical Medical Center of Tissue Engineering and Regeneration Xinxiang Medical UniversityXinxiangHenan ProvinceChina Institutes of Health Central Plain Xinxiang Medical UniversityXinxiangHenan ProvinceChina School of Public Health Xinxiang Medical UniversityXinxiangHenan ProvinceChina

Traumatic brain injury and Alzheimer's disease share pathological similarities,including neuronal loss,amyloid-βdeposition,tau hyperphosphorylation,blood-brain barrier dysfunction,neuroinflammation,and cognitive ***,traumatic brain injury can exacerbate Alzheimer's disease-like pathologies,potentially leading to the development of Alzheimer's *** offer a potential solution by facilitating the delive ry of small interfering RNAs across the blood-brain barrier for the targeted silencing of key pathological genes implicated in traumatic brain injury and Alzheimer's disease.U nlike traditional approaches to neuro regeneration,this is a molecula r-targeted strategy,thus avoiding non-specific drug *** review focuses on the use of nanocarrier systems for the efficient and precise delive ry of siRNAs,discussing the advantages,challenges,and future *** principle,siRNAs have the potential to target all genes and non-targetable protein s,holding significant promise for treating various *** the various therapeutic approaches currently available for neurological diseases,siRNA gene silencing can precisely"turn off"the expression of any gene at the genetic level,thus radically inhibiting disease progression;however,a significant challenge lies in delivering siRNAs across the blood-brain *** have received increasing attention as an innovative drug delive ry tool fo r the treatment of brain *** are considered a potential therapeutic strategy with the advantages of being able to cross the blood-brain barrier,targeted drug delivery,enhanced drug stability,and multifunctional *** use of nanoparticles to deliver specific modified siRNAs to the injured brain is gradually being recognized as a feasible and effective *** this strategy is still in the preclinical exploration stage,it is expected to achieve clinical translation in the future,creating a new field of molecular tar

关键词： blood-brain barrier cognitive dysfunction exosomes gene silencing immunotherapy inorganic nanomaterials liposome nanoparticles neuroinflammation polymer nanoparticles stem cells