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Research and design of CRT-based homomorphic ciphertext database system

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High-Confidence Computing 2022年第4期2卷 1-7页

作者： De Zhao zhenzhen li Haiyang Ding zhenzhen Zhang Zichen li College of Information Engineering Beijing Institute of Graphic CommunicationBeijingChina Digital Copyright Protection Technology Research Center Beijing Institute of Graphic CommunicationBeijingChina

The cloud’s storage and query of private information have the cryptographic scholar due to the proliferation of cloud *** the traditional query mode,the private information stored in the cloud is at risk of being *** order to solve this problem,a cloud ciphertext database system based on homomorphic encryption is a valid *** paper presents a new cloud ciphertext database system model,which is based on the existing ciphertext database mode research and homomorphic *** paper also implements a ciphertext database system based on a CRT-based additive homomorphic scheme according to the *** theoretical analysis,the model is CPA-level safe and *** experimental results show that users can correctly query and download the data in the ciphertext database on the untrusted cloud server through the model,and it has efficiency advantages.

关键词： Ciphertext database Homomorphic encryption Chinese remainder theorem

Global dynamics of delayed intraguild predation model with intraspecific competition

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International Journal of Biomathematics 2018年第8期11卷 425-463页

作者： zhenzhen li Binxiang Dai School of Mathematics and Statistics Central South University Changsha Hunan 410083 P. R. China

A delayed intraguild predation (IGP) model with intraspecific competition is considered. It is shown that the delay has a destabilizing effect and induces oscillations. The global existence results of periodic solutions bifurcating from the positive equilibrium are established. It is shown that there exists at least one nontrival periodic solution when the delay passes through a certain critical value. Numerical simulations are performed to illustrate our theoretical results and show that intraspecific competition can also affect the stability of the positive equilibrium of the system.

关键词： IGP model delay Hopf bifurcation global Hopf bifurcation

Unconditional Optimal Error Estimates for the Transient Navier-Stokes Equations with Damping

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Advances in Applied Mathematics and Mechanics 2022年第1期14卷 248-274页

作者： Minghao li zhenzhen li Dongyang Shi College of Science Henan University of TechnologyZhengzhouHenan 450001China College of Mathematics and Information Science Zhengzhou University of Light IndustryZhengzhouHenan 450002China School of Mathematics and Statistics Zhengzhou UniversityZhengzhouHenan 450001China

In this paper,the transient Navier-Stokes equations with damping are ***,the semi-discrete scheme is discussed and optimal error estimates are ***,a linearized backward Euler scheme is *** the error split technique,the Stokes operator and the H^(-1)-norm estimate,unconditional optimal error estimates for the velocity in the norms L^(∞)(L^(2)) and L^(∞)(H^(1)),and the pressure in the norm L^(∞)(L^(2))are ***,two numerical examples are provided to confirm the theoretical analysis.

关键词： Navier-Stokes equations with damping linearized backward Euler scheme error splitting technique unconditional optimal error estimates

Room-temperature chlorine gas sensor based on CdSnO_(3) synthesized by hydrothermal process

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Journal of Advanced Ceramics 2013年第1期2卷 31-36页

作者： Xiaohua ZHAO zhenzhen li Xiangdong LOU Meng li Ning ZHANG School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

The perovskite-structure CdSnO_(3) was obtained by calcinating CdSnO_(3)·3H_(2)O precursor at 550℃,which was synthesized by hydrothermal process at 170℃for 16 *** phase and microstructure of the obtained CdSnO_(3) powders were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The CdSnO_(3) powders exhibit uniformly cubic structure with side length of about 100 *** effects of working temperature and concentration of detected gas on the gas response were *** selectivity of chlorine gas against other gases and response-recovery time of the sensor were also *** results reveal that the CdSnO_(3) gas sensor has enhanced sensing properties to 1-10 ppm chlorine gas at room temperature;the value of gas response can reach 1338.9 to 5 ppm chlorine ***,the sensor shows good selectivity and quick response behavior(23 s)to chlorine gas,indicating its application in detecting chlorine gas at room temperature in the future.

关键词： chlorine gas sensor room temperature CdSnO_(3) hydrothermal process

A New DS-SS Signal Detection Trial Algorithm for False Alarm Rejection Based on Motion Parameters Constraint

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Chinese Journal of Electronics 2015年第1期24卷 110-114页

作者： CUI Wei WANG Fengyun li zhenzhen JIN Qianyu ZHANG Yunhan Radar Research Laboratory School of Information and ElectronicsBeijing Institute of Technology

To reject false alarm, a new detection trial algorithm named motion parameters constraint for Direct sequence spread spectrum(DS-SS) signal is proposed. A mathematical model based on uniform motion between two adjacent detections is established to analyze the overall performance of the proposed trial algorithm. Motion parameters constraint is applied to the conventional variable dwell time Tong trial algorithm. The expressions of the false alarm probability and detection probability are derived. Theoretical analysis and simulation results demonstrate that in comparison with the conventional M of N trial algorithm, Tong trial algorithm and Tong trial algorithm based on near neighbor constraint. The proposed trial algorithm can significantly reduce the false alarm probability and enhance the detection ability without increasing search speed and complexity.

关键词： DS-SS Acquisition Motion parameters constraint False alarm.

A Runge Kutta Discontinuous Galerkin Method for Lagrangian Compressible Euler Equations in Two-Dimensions

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Communications in Computational Physics 2014年第4期15卷 1184-1206页

作者： zhenzhen li Xijun Yu Jiang Zhu Zupeng Jia School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026P.R.China Graduate School China Academy of Engineering PhysicsBeijing 100088P.R.China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088P.R.China National Laboratory for Scientific Computing LNCC/MCTIAvenida Getúlio Vargas 33325651-075 PetrópolisRJBrazil

This paper presents a new Lagrangian type scheme for solving the Euler equations of compressible gas *** this new scheme the system of equations is discretized by Runge-Kutta Discontinuous Galerkin(RKDG)method,and the mesh moves with the fluid *** scheme is conservative for the mass,momentum and total energy and maintains second-order *** scheme avoids solving the geometrical part and has free *** of some numerical tests are presented to demonstrate the accuracy and the non-oscillatory property of the scheme.

关键词： Lagrangian type scheme compressible Euler equations RKDG method conservative scheme

Laser Ablation ICP-MS U-Pb Zircon Geochronology of Granitoids and Quartz Veins in the Shihu Gold Mine, Taihang Orogen, North China: Timing of Gold-mineralization and Tectonic Implications

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Acta Geologica Sinica(English Edition) 2012年第5期86卷 1211-1224页

作者： CAO Ye li Shengrong XIONG Xianxiao li zhenzhen liU Xiaobin YAO Meijuan ZHANG Huafeng State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China General Institute of Chemical Geology Survey China Chemical Geology and Mine BureauBeijing 100013China School of Earth Science and Resources China University of GeosciencesBeijing 100083China

The Shihu gold deposit, situated in the Taihang Mesozoic orogen of the North China Craton （NCC）, is hosted by ductile-brittle faults within Archean metamorphic core complex. The deposit is characterized by gold-bearing quartz-polymetallic sulfides veins. The Mapeng granitoids stock and intermediate-basic dikes intruded the metamorphic basement rocks, and are spatially related to gold mineralization. Detailed laser ablation inductively coupled plasma mass spectrometry （LA ICP-MS） U-Pb zircon ages of the granitic rocks, dykes and mineralized quartz veins in the studied area reveal its magmatic and mineralized history. The mineralized quartz veins contain inherited zircons with ages of about 2.55 Ga and 1.84 Ga, probably coming from the basement. These two Precambrian events are coeval with those in other parts of the NCC. The Mapeng granitoid stock, the largest intrusion in the area, was emplaced at ca. 130 Ma, and is coeval with magmatic zircon populations from diorites and quartz diorite pophyrites in the same region. The ca. 130 Ma magmatism and gold mineralization were most likely related to an underplating event that took place in the Taihang orogen at Late Mesozoic. The timing of gold mineralization with respect to felsic magmatism in the area is similar to those observed in other major gold-producing provinces in the NCC. This episode is simultaneous with those in the eastern margin of NCC, indicative of a widespread late Yanshanian metallogenic event that was a response to the Early Cretaceous lithosphere in the eastern NCC, in which the mesothermal gold deposits were formed from similar tectono-magmatic environments.

关键词： zircon U-Pb geochronology Shihu gold deposit geodynamic setting North China Craton

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Laser probe ^(40)Ar/^(39)Ar dating for quartz from auriferous quartz veins in the Shihu gold deposit,western Hebei Province,North China

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Chinese Journal Of Geochemistry 2010年第4期29卷 438-445页

作者： CAO Ye li Shengrong ZHANG Huafeng AO Chong li zhenzhen liU Xiaobin State Key Laboratory of Geological Processes and Mineral Resources China University ofGeosciences Beijing 100083 China School of Earth Science and Resources China University of Geosciences Beijing 100083 China Department of Earth Sciences Laurentian University Sudbury P3E2C6 Canada

The Shihu gold deposit is situated in the central shear zone of the Meso-Cenozoic Fuping metamorphic core complex in the middle-northern part of the Taihang *** kind of gold deposits named after 'Shihu type' widely occurs in this ***-bearing quartz veins are their most important industrial *** laser 40Ar/39Ar geochronology of the mineralized quartz veins in the study area reveals details of its tectono-magmatic *** 40Ar/39Ar ages for the quartz are between 134.4 Ma and 155.9 Ma with a mean age of 141±4 Ma on the isochron line and 139±7 Ma on the inverse isochron line,respectively,which is interpreted to be the best estimate of the crystalline age of the quartz *** gold mineralization was most likely related to an underplating event that took place in the northern part of the Taihang Mountain at ca.140 *** timing of gold mineralization in the area is similar to those observed in other major gold-producing provinces in the *** episode is simultaneous with those in the eastern NCC,indicative of a widespread late Yanshanian metallogenic event that was a response either to the subduction of the Izanagi-Pacific plate beneath eastern China or to the removal of the Early Cretaceous lithosphere in the eastern *** ore-forming material sources may be the Early Precambrian metamorphic basement,instead of intermediate-acid rock bodies and dykes.

关键词：含金石英脉激光探针中国东部金矿床河北省西部平均年龄成矿时间

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The poly(ADP-ribosyl)ation of BRD4 mediated by PARP1 promoted pathological cardiac hypertrophy

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Acta Pharmaceutica Sinica B 2021年第5期11卷 1286-1299页

作者： zhenzhen li Zhen Guo Rui Lan Sidong Cai Zhirong lin Jingyan li Junjian Wang Zhuoming li Peiqing liu Department of Pharmacology and Toxicology School of Pharmaceutical SciencesNational and Local United Engineering Lab of Druggability and New Drugs EvaluationGuangdong Engineering Laboratory of Druggability and New Drug EvaluationGuangdong Provincial Key Laboratory of New Drug Design and EvaluationSun Yat-sen UniversityGuangzhou 510006China Center for Cardiovascular Research and Division of Cardiology Washington University School of MedicineSt.LouisMO 63101USA International Institute for Translational Chinese Medicine School of Pharmaceutical SciencesGuangzhou University of Chinese MedicineGuangzhou 510006China

The bromodomain and extraterminal(BET)family member BRD4 is pivotal in the pathogenesis of cardiac ***4 induces hypertrophic gene expression by binding to the acetylated chromatin,facilitating the phosphorylation of RNA polymerases II(Pol II)and leading to transcription *** present study identified a novel post-translational modification of BRD4:poly(ADPribosyl)ation(PARylation),that was mediated by poly(ADP-ribose)polymerase-1(PARP1)in cardiac ***4 silencing or BET inhibitors JQ1 and MS417 prevented cardiac hypertrophic responses induced by isoproterenol(ISO),whereas overexpression of BRD4 promoted cardiac hypertrophy,confirming the critical role of BRD4 in pathological cardiac ***1 was activated in ISOinduced cardiac hypertrophy and facilitated the development of cardiac ***4 was involved in the prohypertrophic effect of PARP1,as implied by the observations that BRD4 inhibition or silencing reversed PARP1-induced hypertrophic responses,and that BRD4 overexpression suppressed the antihypertrophic effect of PARP1 *** of BRD4 and PARP1 were observed by coimmunoprecipitation and *** of BRD4 induced by PARP1 was investigated by PARylation *** response to hypertrophic stimuli like ISO,PARylation level of BRD4 was elevated,along with enhanced interactions between BRD4 and *** investigating the PARylation of truncation mutants of BRD4,the C-terminal domain(CTD)was identified as the PARylation modification sites of *** of BRD4 facilitated its binding to the transcription start sites(TSS)of hypertrophic genes,resulting in enhanced phosphorylation of RNA Pol II and transcription activation of hypertrophic *** present findings suggest that strategies targeting inhibition of PARP1-BRD4 might have therapeutic potential for pathological cardiac hypertrophy.

关键词： BRD4 PARP1 PARylation Isoproterenol Cardiac hypertrophy RNA Pol II Transcription activation Hypertrophic genes

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