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Puerarin, an isoflavone compound extracted from Gegen (Radix Puerariae Lobatae), modulates sclera remodeling caused by extremely low frequency electromagnetic fields

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Journal of Traditional Chinese Medicine 2016年第5期36卷 678-682页

作者： tian tian Cai Xiaojing Zhu Huang Department of Ophthalmology Xinhua Hospital Shanghai Jiao Tong University School of Medicine

OBJECTIVE: To evaluate the protective effect of puerarin [an isoflavone compound extracted from Gegen(Radix Puerariae Lobatae)] in scleral remodeling induced by extremely low frequency electromagnetic fields(ELF-EMFs).METHODS: Human fetal scleral fibroblasts(HFSFs)were divided into 5 groups:(a) untreated controls;(b) cells treated with ELF-EMFs;(c) cells treated with ELF-EMFs and puerarin 0.1 μM;(d) cells treated with ELF-EMFs and puerarin 1 μM;(e) cells treated with ELF-EMFs and puerarin 10 μM. Cell proliferation activity was measured by the cell-counting kit-8 assay. Matrix metalloproteinase-2(MMP-2) activity was measured by gelatin ***-2 and collagenⅠ(COL1A1) m RNA, protein expression were measured by Real-Time polymerase chain reaction, Western blot analysis, ***: Puerarin reduced the inhibition in cell proliferation, MMP-2 activity, m RNA, protein expression of HFSFs exposed to ELF-EMFs and enhanced the COL1A1 m RNA and protein ***: Puerarin was found to participate in the matrix remodeling process. It might be a potential agent for the treatment of extracellular matrix degradation of sclera associated with ocular conditions.

关键词： Puerarin Pueraria lobata Sclera Fibroblast Matrix metalloproteinase 2 Collagen type Ⅰ Electromagnetic fields

DeepSI:A Sensitive-Driven Testing Samples Generation Method of Whitebox CNN Model for Edge Computing

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Tsinghua Science and Technology 2024年第3期29卷 784-794页

作者： Zhichao Lian Fengjun tian School of Cyber Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

In recent years,Deep Learning(DL)technique has been widely used in Internet of Things(IoT)and Industrial Internet of Things(IIoT)for edge computing,and achieved good *** more and more studies have shown the vulnerability of neural ***,it is important to test the robustness and vulnerability of neural *** specifically,inspired by layer-wise relevance propagation and neural network verification,we propose a novel measurement of sensitive neurons and important neurons,and propose a novel neuron coverage criterion for robustness *** on the novel criterion,we design a novel testing sample generation method,named DeepSI,which involves definitions of sensitive neurons and important ***,we construct sensitive-decision paths of the neural network through selecting sensitive neurons and important ***,we verify our idea by setting up several experiments,then results show our proposed method achieves superior performances.

关键词： neuron sensitivity Layer-wise Relevance Propagation(LRP) neural network verification deeplearning testing

Active disturbance rejected predictive functional control for space vehicles with RCS

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Journal of Systems Engineering and Electronics 2018年第5期29卷 1022-1035页

作者： tian Jiayi ZHANG Shifeng College of Aerospace Science and Engineering National University of Defense Technology

Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitable internal uncertainties and external disturbances in practice, this inherent nonlinear character always hinders space vehicles autopilot from pursuing precise tracking performance. Compared to most of pre-existing methodologies that passively suppress the uncertainties and disturbances, a design based on predictive functional control(PFC) and generalized extended state observer(GESO) is firstly proposed for three-axis RCS control system to actively reject that with no requirement for additional fuel consumption. To obtain a high fidelity predictive model on which the performance of PFC greatly depends, the nonlinear coupling multiple-input multiple-output(MIMO) flight dynamics model is parameterized as a state-dependent coefficient form. And based on that, a MIMO PFC algorithm in state space domain for a plant of arbitrary orders is deduced in this *** internal uncertainties and external disturbances are lumped as a total disturbance, which is estimated and cancelled timely to further enhance the robustness. The continuous control command synthesised by above controller-rejector tandem is finally modulated by pulse width pulse frequency modulator(PWPF) to on-off signals to meet RCS requirement. The robustness and feasibility of the proposed design are validated by a series of performance comparison simulations with some prominent methods in the presence of significant perturbations and disturbances, as well as measurement noise.

关键词： reaction control system(RCS) predictive functional control(PFC) generalized extended state observer(GESO) pulse width pulse frequency(PWPF) multiple-input multiple-output(MIMO)

An Isotropic SPPP Model for Femtocells Networks with Outage Probability Constraints

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Chinese Journal of Electronics 2015年第4期24卷 824-831页

作者： ZHANG Jun tian Hui State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunication

Femtocells have been considered as a costeffective solution to unload traffic from already overburdened macrocell networks in 4G cellular networks. The severe interference in spectrum-sharing macro and femto networks may cause User-equipment(UE) to experience outage. We derive an utmost isotropic Spatial Poisson point process(SPPP) density for Femtocell access points(FAPs) under the UEs’ outage constraints. Based on the derived isotropic SPPP density, we propose a distributed transmit probability self-regulation scheme for an FAP to adapt its transmit probability per Transmission time interval(TTI). The scheme adjusts the homogeneous distributed FAPs in practice deployment to the proposed isotropic one. Simulation results show that the derived density can fulfill the outage probability constraints of UEs while accommodating the maximum femtocells. The selfregulation scheme can adapt the femtocell transmit probabilities to provide reliable downlink service, for even a large number of femtocells per cell site.

关键词： Heterogeneous network Stochastic geometry Outage probability

Mott insulator-superfluid phase transition in a detuned multi-connected Jaynes-Cummings lattice

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Science China(Physics,Mechanics & Astronomy) 2015年第7期58卷 17-22页

作者： SEO Kangjun tian Lin School of Natural Sciences University of California

The connectivity and tunability of superconducting quantum devices provide a rich platform to build quantum simulators and study novel many-body physics. Here we study quantum phase transition in a detuned multi-connected Jaynes-Cummings lattice, which can be constructed with superconducting circuits. This model is composed of alternatively connected qubits and cavity *** a numerical method, we show that by varying the detuning between the qubits and the cavities, a phase transition from the superfluid phase to the Mott insulator phase occurs at commensurate fillings in a one-dimensional array. We study the phase transition in lattices with symmetric and asymmetric couplings, respectively.

关键词： superconducting quantum devices quantum simulation Jaynes-Cummings lattice phase transition

Large-scale video compression： recent advances and challenges

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Frontiers of Computer Science 2018年第5期12卷 825-839页

作者： Tao tian Hanli WANG Department of Computer Science and Technology Tongji University Shanghai 201804 China Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 200092 China Shanghai Engineering Research Center of Industrial Vision Perception & Intelligent Computing Shanghai 200092 China

The evolution of social network and multimedia technologies encourage more and more people to generate and upload visual information, which leads to the generation of large-scale video data. Therefore, preeminent compression technologies are highly desired to facilitate the storage and transmission of these tremendous video data for a wide variety of applications. In this paper, a systematic review of the recent advances for large-scale video compression （LSVC） is presented. Specifically, fast video coding algorithms and effective models to improve video compression efficiency are introduced in detail, since coding complexity and compression efficiency are two important factors to evaluate video coding approaches. Finally, the challenges and fu- ture research trends for LSVC are discussed.

关键词： large-scale video compression fast video coding compression efficiency

Theoretical relationships between first flush of roof runoff and influencing factors

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 746-757页

作者： Biao WANG tian L State Key Lab of Pollution Control and Resource Reuse Tongji University Shanghai 20092 China

Considering the short length of building roofs, a theoretical analysis of the first flush of roof runoff was conducted based on the kinematic wave and pollutant erosion equations. This mathematical derivation with analytical solutions predicts pollutant mass first flush (MFF), mean concentration of initial runoff (MCIF), mean concentration of roof runoff (MCRR) with diversion of initial portion and residual mass available on the bed surface (RS) after the entire runoff under the condition of con-stant excess rainfall. And the effects of the associated influencing factors (roof length, roof gradient, roof surface roughness, rainfall intensity, rainfall duration, and erosion coefficients) on them were discussed while the values of parameters referred to the previous studies. The results showed that for roofs whose length is shorter than 20 m, both the increase in roof length and roof gradient and the decrease in roof surface roughness result in larger MFF and MCIF and smaller MCRR and RS, which is beneficial to water reuse and pollution reduction. The theoretical relationship between the first flush and the influencing factors may aid the planning and design of roof in terms of rainwater utilization or diffuse pollution control.

关键词： Roof runoff Kinematic wave equation Pollutant erosion equation First flush

ACOUSTOELASTIC THEORY FOR FLUID-SATURATED POROUS MEDIA

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Acta Mechanica Solida Sinica 2014年第1期27卷 41-53页

作者： Huaqing Wang Jiayong tian Institute of Crustal Dynamics China Earthquake Administration

Based on the finite deformation theory of the continuum and poroelastic theory, the aeoustoelastic theory for fluid-saturated porous media （FSPM） in natural and initial coordi- nates is developed to investigate the influence of effective stresses and fluid pore pressure on wave velocities. Firstly, the assumption of a small dynamic motion superimposed on a largely static pre- deformation of the FSPM yields natural, initial, and final configurations, whose displacements, strains, and stresses of the solid-skeleton and the fluid in an FSPM particle could be described in natural and initial coordinates, respectively. Secondly, the subtraction of initial-state equations of equilibrium from the final-state equations of motion and the introduction of non-linear constitu- rive relations of the FSPM lead to equations of motion for the small dynamic motion. Thirdly, the consideration of homogeneous pre-deformation and the plane harmonic form of the small dynamic motion gives an acoustoelastic equation, which provides analytical formulations for the relation of the fast longitudinal wave, the fast shear wave, the slow shear wave, and the slow longitudinal wave with solid-skeleton stresses and fluid pore-pressure. Lastly, an isotropic FSPM under the close-pore jacketed condition, open-pore jacketed condition, traditional unjacketed condition, and triaxial condition is taken as an example to discuss the velocities of the fast and slow shear waves propagating along the direction of one of the initial principal solid-skeleton strains. The detailed discussion shows that the wave velocities of the FSPM are usually influenced by the effective stresses and the fluid pore pressure. The fluid pore-pressure has little effect on the wave velocities of the FSPM only when the components of the applied initial principal solid-skeleton stresses or strains are equal, which is consistent with the previous experimental results.

关键词： acoustoelasticity fluid-saturated porous media wave velocity the effective stress fluid pore pressure

Syntheses and Structures of Lanthanide Complexes with Isonicotinate

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Chinese Journal of Structural Chemistry 2005年第7期24卷 816-820,738页

作者： ZHANGMan-Bo ZHENGShou-tian StateKeyLaboratoryofStructuralChemist~. FujianInstituteofResearchontheStructureofMatterTheChineseAcademyofSciencesFuzhouFujian350002China

The crystal structures of two coordination polymers [Ln(IN)3(H2O)2]n (Ln = Nd 1, Gd 2; IN = isonicotinate) were determined by single-crystal X-ray diffraction and further chara- cterized by IR, elemental analysis and thermogravimetric analysis. Crystal data for 1: monoclinic, space group P21/c, a = 9.6636(5), b = 19.7532(10), c = 11.6183(6) ?, β = 112.032(1)°, V = 2055.83(18) ?3, Z = 4, Dc = 1.766 g/cm3, F(000) = 1076, μ = 2.575 mm–1 and R = 0.0493; Crystal data for 2: monoclinic, space group C2/c, a = 20.251(2), b = 11.6199(11), c = 9.8240(9) ?, β = 115.505(3)°, V = 2086.4(3) ?3, Z = 4, Dc = 1.781 g/cm3, F(000) = 1092, μ = 3.228 mm–1 and R = 0.0695. In the title compounds, the center atoms Ln(III) are in a distorted square antiprismatic geometry and linked by bridging isonicotinate to form an infinite chain. The intermolecular hydro- gen bonds lead to the formation of three-dimensional supramolecular structures.

关键词： crystal structure lanthanide isonicotinate hydrothermal synthesis