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Detecting Arrays and Their Optimality

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2309-2318页

作者： Yu TANG jian xing YIN Department of Mathematics Soochow University Suzhou 215006 P. R. China

Detecting arrays were proposed by Colbourn and McClary in 2008, which are of interest in generating software test suites to cover all t-sets of component interactions and detect interaction faults in component-based systems. So far, optimality and constructions of detecting arrays have not been studied systematically. Indeed, no useful benchmark to measure the optimality of detecting arrays has previously been given, and only some sporadic examples of optimal detecting arrays have been found. This paper tries to take the first step by presenting a lower bound on the size of detecting arrays and some methods of constructing optimal detecting arrays. A number of infinite series of optimal detecting arrays are then obtained.

关键词： Detecting arrays interaction faults bounds optimality constructions

Ultrasonic Study on Jahn-Teller Distortions in La1/3Sr2/3CoO3

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Chinese Journal of Chemical Physics 2008年第2期21卷 136-140页

作者： jian-xing Yi Hui Kong Chang-fei Zhu Laboratory of Advanced Functional Materials and Devices Department of Materials Science and Engineering University of Science and Technology of China Hefei 230025 China

The longitudinal ultrasonic velocity （V1）, attenuation （α1）, magnetization and resistivity of single phase polycrystalline La1/3Sr2/3CoO3 were measured as a function of temperature from 20 K to 300 K. The resistivity shows metallic behavior in the whole temperature range and a kink at 235 K was observed, which coincides with the ferromagnetic transition temperature （Tc）. As the temperature cools down from Tc, the V1 softens conspicuously at beginning and reaches a minimum at 120 K. After that the V1 dramatically stiffens below 120 K accompanied by a wide attenuation peak. The analysis of the results suggests that these ultrasonic anomalies ;nay correspond to local lattice distortions via the Jahn-Teller effect of intermediate spin Co^3＋.

关键词： La1/3Sr2/3CoO3 Ultrasonic velocity and attenuation Jahn-Teller effect

Distribution prediction of moisture content of dead fuel on the forest floor of Maoershan national forest, China using a LoRa wireless network

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Journal of Forestry Research 2022年第3期33卷 899-909页

作者： Bo Peng Jiawei Zhang jian xing Jiuqing Liu Northeast Forestry University Harbin150040People’s Republic of China

The moisture content of dead forest fuel is an important indicator of risk levels of forest fires and prediction of fire spread. Moisture distribution is important to determine wild fire rating. However, it is often difficult to predict moisture distribution because of a complex terrain, changeable environments and low cover of commercial communication signals inside the forest. This study proposes a moisture content prediction system composed of environmental data collected using a long range radio frequency band 433 MHz wireless sensor network and data processing for moisture prediction based on a BP (back-propagation) neural network. In the fall of 2019, twenty nodes for the collection of environmental data were placed in four forest stands of Maoershan National Forest for a month;7440 sets of data including temperature, humidity, wind speed and air pressure were obtained. Half the data were used as a training set, the other as a testing set for a BP neural network. The results show that the average absolute error between the predicted value and the real value of moisture content of fuels of Larix gmelini, Betula platyphylla, Juglans mandshurica, and Quercus mongolica stands was 0.94%, 0.21%, 0.86%, 0.97%, respectively. The prediction accuracy was relatively high. The proposed distributed moisture content prediction method has the advantages of wide coverage and good real-time performance;at the same time, it is not limited by commercial signals and so it is especially suitable for forest fire prediction in remote mountainous areas.

关键词： Distributed moisture content prediction Dead fuel BP neural network

Thermal Entanglement of a Two-Qubit XXZ Heisenberg Chain with Dzialoshinski-Moriya Interaction

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Communications in Theoretical Physics 2009年第11期52卷 817-819页

作者： QIAN Li FANG jian-xing School of Physical Science and Technology Suzhou University Suzhou 215006 China

The effect of DziaJoshinski-Moriya （DM） interaction on thermal entanglement of a two-qubit XXZ spin chain in a homogenous magnetic field is investigated. It is found that the DM interaction can enhance thermal entan... 详细信息

关键词： XXZ spin chain DM interaction thermal entanglement

Connes' Distance of One-Dimensional Lattices:General Cases

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Communications in Theoretical Physics 2001年第11期36卷 519-522页

作者： DAI jian SONG xing-Chang Department of Physics Peking UniversityBeijing 100871China Department of PhysicsPeking UniversityBeijing 100871China

Connes' distance formula is applied to endow linear metric to three 1D lattices of different topologies with a generalization of lattice Dirac operator written down by Dimakis et *** contain a non-unitary *** interpre... 详细信息

关键词： Connes' distance,one-dimensional lattice,Dirac operator,link-variable,lattice spacing,parallel transport

Effect of trace HA on microstructure, mechanical properties and corrosion behavior of Mg-2Zn-0.5Sr alloy

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Journal of Materials Science & Technology 2018年第2期34卷 299-310页

作者： jian-xing Li Yuan Zhang Jing-Yuan Li jian-Xin Xie School of Materials Science and Engineering University of Science and Technology Beijing Institute for Advanced Materials and Technology University of Science and Technology Beijing

Effect of the addition of trace HA particles into Mg-2Zn-0.5Sr on microstructure, mechanical properties, and bio-corrosion behavior was investigated in comparison with pure Mg. Microstructures of the Mg-2Zn-0.5Sr-xHA composites （x= 0, 0.1 and 0.3 wt%） were characterized by optical microscopy （OM）, scanning electron microscopy （SEM） equipped with energy dispersion spectroscopy （EDS） and X-ray diffraction （XRD）. Results of tensile tests at room temperature show that yield strength （YS） of Mg- 2Zn-0.5Sr/HA composites increases significantly, but the ultimate tensile strength （UTS） and elongation decrease with the addition of HA particles from 0 up to 0.3 wt%. Bio-corrosion behavior was investigated by immersion tests and electrochemical tests. Electrochemical tests show that corrosion potential （Ecorr） of Mg-2Zn-0.5Sr/HA composites significantly shifts toward nobler direction from -1724 to -1660 mVscE and the corrosion current density decreases from 479.8 to 280.8 ***^-2 with the addition of HA particles. Immersion tests show that average corrosion rate of ***/HA composites decreases from 11.7 to 9.1 mm/year with the addition of HA particles from 0 wt% up to 0.3 wt%. Both microstructure and mechanical properties can be attributed to grain refinement and mechanical bonding of HA particles with second phases and α-Mg matrix. Bio-corrosion behavior can be attributed to grain refinement and the formation of a stable and dense CaHPO4 protective film due to the adsorption of Ca^2＋ on HA particles. Our analysis shows that the Mg-2Zn-0.5Sr/0.3HA with good strength and corrosion resistance can be a good material candidate for biomedical applications.

关键词： Magnesium alloys Bio-composites Hydroxyapatite Microstructure Mechanical property Bio-corrosion behavior

Sparse Modal Decomposition Method Addressing Underdetermined Vortex-Induced Vibration Reconstruction Problem for Marine Risers

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China Ocean Engineering 2024年第2期38卷 285-296页

作者： DU Zun-feng ZHU Hai-ming YU jian-xing State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation School of Civil EngineeringTianjin UniversityTianjin 300350China

When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real *** problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration ***,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known *** study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal *** the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring.

关键词： motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing

Blind false data injection attacks in smart grids subject to measurement outliers

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Journal of Control and Decision 2022年第4期9卷 445-454页

作者： xing-jian Ma Huimin Wang College of Information Science and Engineering Northeastern UniversityShenyangPeople’s Republic of China

False data injection attacks(FDIAs)can manipulate measurement data from Supervisory Control and Data Acquisition(SCADA)system and threat state estimation in smart *** FDIAs(BFDIAs)enhance traditional FDIAs,which eliminate the limitation of grasping measurement Jacobian matrix H in advance,but when there are outliers in measurement data,attack performance is *** this paper,improved BFDIAs are *** off-line phase,lowdimensional measurement matrix without outliers calculated by Linear Local Tangent Space Alignment algorithm(LLTSA)is sent into Continuous Deep Belief Network(CDBN)as training data to learn their probability *** on-line phase,real-time low-dimensional measurement matrix with outliers are sent into the trained model as inputs,and outputs are reconstructed by the probability distribution in off-line phase,which eliminates the influence of outliers *** are implemented on PJM 5-bus and IEEE 14-bus systems to verify the performance of proposed strategy compared with PCA-based BFDIAs.

关键词： Smart grids blind false data injection attacks measurement outliers continuous deep belief network linear local tangent space alignment algorithm

Measuring moisture content of dead fine fuels based on the fusion of spectrum meteorological data

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Journal of Forestry Research 2023年第5期34卷 1333-1346页

作者： Bo Peng Jiawei Zhang jian xing Jiuqing Liu Mingbao Li Northeast Forestry University Harbin 150040People’s Republic of China

Dead fine fuel moisture content(DFFMC)is a key factor affecting the spread of forest fires,which plays an important role in evaluation of forest fire *** order to achieve high-precision real-time measurement of DFFMC,this study established a long short-term memory(LSTM)network based on particle swarm optimization(PSO)algorithm as a measurement model.A multi-point surface monitoring scheme combining near-infrared measurement method and meteorological measurement method is *** near-infrared spectral information of dead fine fuels and the meteorological factors in the region are processed by data fusion technology to construct a spectral-meteorological data *** surface fine dead fuel of Mongolian oak(Quercus mongolica *** Ledeb.),white birch(Betula platyphylla Suk.),larch(Larix gmelinii(Rupr.)Kuzen.),and Manchurian walnut(Juglans mandshurica Maxim.)in the maoershan experimental forest farm of the Northeast Forestry University were *** used the PSO-LSTM model for moisture content to compare the near-infrared spectroscopy,meteorological,and spectral meteorological fusion *** results show that the mean absolute error of the DFFMC of the four stands by spectral meteorological fusion method were 1.1%for Mongolian oak,1.3%for white birch,1.4%for larch,and 1.8%for Manchurian walnut,and these values were lower than those of the near-infrared method and the meteorological *** spectral meteorological fusion method provides a new way for high-precision measurement of moisture content of fine dead fuel.

关键词： Near infrared spectroscopy Meteorological factors Data fusion Long-term and short-term memory network Particle swarm optimization algorithm