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Stochastic Resonance Induced by an Asymmetric Two-state Noise

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Communications in Theoretical Physics 2005年第3X期44卷 426-430页

作者： han Yin-xia Graduate School of China Academy of Engineering Physics P.O. Box 2101 Beijing 100088 China CCAST (World Laboratory) P.O. Box 8730 Beijing 100080 China Center for Nonlinear Studies Institute of Applied Physics and Computational Mathematics P.O. Box 8009(28) Beijing 100088 China

Stochastic resonance （SR） phenomenon of the system that is subject to the asymmetric two-state noise is investigated from the broad sense. It is shown that the amplitudes of the output signal exhibit the non-monotonic dependence on the input signal frequency w, and the parameters describing the asymmetric two-state noise, such as the transition rate A, the order parameter k describing the asymmetric degree of the two-state noise, and the noise strength D.

关键词： dichotomous noise stochastic resonance the first moment

A 2-D NUMERICAL IRREGULAR WAVE TANK AND ITS VERIFICATION

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Journal of Hydrodynamics 2005年第2期17卷 222-227页

作者： LIBen-xia YUXi-ping YUYu-xiu DepartmentofHydrauhcEngineering TsinghuaUniversityBeijing100084China StateKeyLaboratoryofCoastalandOffshoreEngineering DalianUniversityofTechnologyDalian116024China

A two-dimensional numerical irregular wave tank based on the potential wave theory was developed. A source term was used inside the domain to generate waves, and outgoing waves were dissipated by sponge layers and transmitted by radiation boundary. The σ-coordinate transformation was introduced to map the time-dependent irregular physical domain to a fixed regular computational domain, and thus the free surface and bottom boundary conditions could be implemented precisely. The model was verified by simulating the nonlinear regular and irregular wave propagation on constant-depth water, as well as regular waves reflected from a vertical wall, and satisfactory agreement between numerical results and analytical solutions was obtained. The present numerical model is proved to be an effective tool for a long-duration simulation of coastal wave dynamics where the wave reflection is significant.

关键词： irregular waves numerical wave tank source wave-generating method σ-coordinate transformation potential wave theory

Thermal behaviors and heavy metal vaporization of phosphatized tannery sludge in incineration process

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Journal of Environmental Sciences 2008年第9期20卷 1146-1152页

作者： TANG, ping ZHAO, Youcai xia, Fengyi State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University Shanghai 200092 China Department of Life and Environmental Science Wenzhou University Wenzhou Zhejiang 325007 China

The high concentration of heavy metal (Cu, Cr, Zn, Pb) in tannery sludge causes severe heavy metal emissions in the process of incineration. In the present investigation, the tannery sludge was treated with 85% phosphoric acid before the incineration process in the tube furnace to control the heavy metal emissions. The thermal behavior and heavy metal vaporization of pre-treated tannery sludge were investigated, and X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were also implemente...

关键词： tannery sludge thermal behavior heavy metal vaporization phosphatation

A Cascade Model-Aware Generative Adversarial Example Detection Method

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Tsinghua Science and Technology 2021年第6期26卷 800-812页

作者： Keji han Yun Li Bin xia School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210046China

Deep Neural Networks(DNNs) are demonstrated to be vulnerable to adversarial examples, which are elaborately crafted to fool learning models. Since the accuracy and robustness of DNNs are at odds for the adversarial training method, the adversarial example detection algorithms check whether the specific example is adversarial, which is promising to solve the issue of the adversarial example. However, among the existing methods,model-aware detection methods do not generalize well, while the detection accuracies of the generative-based methods are lower compared to the model-aware methods. In this paper, we propose a cascade model-aware generative adversarial example detection method, namely CMAG. CMAG consists of two first-order reconstructors and a second-order reconstructor, which can illustrate what the model sees to the human by reconstructing the logit and feature maps of the last convolution layer. Experimental results demonstrate that our method is effective and is more interpretable compared to some state-of-the-art methods.

关键词： information security Deep Neural Network(DNN) adversarial example detection

Comparative filtration and dewatering behavior of vitrinite and inertinite of bituminous coal:Experiment and simulation study

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International Journal of Mining Science and Technology 2021年第2期31卷 233-240页

作者： An ping Wencheng xia Yaoli Peng Guangyuan Xie School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou 221116JiangsuChina

The filtration and dewatering of fine clean coal not only ensure industrial water recycle in coal washing plant,but also reduce the moisture of coal product in order to meet the requirements of combustion or coking *** clean coal is mainly composed by organic matter,and the property difference of different organic matter determines the filtration and dewatering *** this investigation,vitrinite and inertinite were separated from a clean bituminous coal,and the comparative filtration and dewatering behavior of vitrinite and inertinite were *** results showed that inertinite has lower dewatering rate and higher filter cake moisture than *** analysis of filter cake structure showed that inertinite particle is easier to be broken into small particles due to the difference of mechanical properties,thus forming more compact filter cake than *** analysis of particle surface properties showed that vitrinite is more hydrophobic than inertinite,which makes water easier drained from filter *** simulation study showed that the structure of inertinite is more porous than that of vitrinite,and the interaction between inertinite and water is stronger than that between vitrinite and *** study provides a theoretical basis for improving coal dewatering by selectively improving coal maceral hydrophobicity.

关键词： Coal maceral groups Filtration Dewatering Simulation

Some nonlinear parameters of PP intervals of pulse main peaks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1256-1262页

作者： han Qing-peng WANG ping School of Biomedical Engineering and Instrument Science Zhejiang University Hangzhou 310027 China

The PP intervals of pulse main peaks from healthy and unhealthy people(arrhythmia) have different nonlinear char-acteristics. In this paper,the extraction of PP intervals of pulse main peaks is achieved by picking up P peaks of pulse wave with wavelet transform. Furthermore,several nonlinear parameters(correlative dimensions,maximum Lyapunov exponents,com-plexity and approximate entropy) of the PP intervals of pulse main peaks extracted from normal and unhealthy pulse signals are calculated,with the results showing that these nonlinear parameters calculated from the main wave interval signals are helpful for analyzing human's health state and diagnosing heart diseases.

关键词： PP intervals of pulse main peaks Phase space reconstruction Correlative dimension Lyapunov exponent Complexity Approximate entropy

Quantifying Land Use Change in Zhejiang Coastal Region,China Using Multi-Temporal Landsat TM/ETM+Images

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Pedosphere 2007年第6期17卷 712-720页

作者： DING han WANG Ren-Chao WU Jia-ping ZHOU Bin SHI Zhou DING Li-xia Institute of Agricultural Remote Sensing and Information System Zhejiang University Hangzhou 310029 （China） Zhejiang Institute of Land Survey and Planning Hangzhou 310007 （China）

Landsat Thematic Mapper （TM） and Enhanced Thematic Mapper Plus （ETM＋） images in 1985, 1986, 1993, 1994 and 2001 were used to quantify the land use and land cover changes （LUCC） in the Zhejiang coastal region with a stratified unsupervised classification technique in conjunction with visual interpretation and to attempt an identification of the socioeconomic driving forces. In level I an overall accurate classification was achieved using a modified Anderson＇s Ⅰ/Ⅱ/Ⅲ-level classification scheme. The overall accuracy of the land use classification at Anderson level Ⅰ were 89.7% （1985）, 91.6% （1993）, and 90.4% （2001）. The most rapid land use change was a dramatic increase in urban or built-up areas, which quadrupled from 1985 to 2001. Over 90% of this newly expanded built-up area was originally paddy fields or other croplands. In different parts of the Zhejiang coastal region, urban land expansion was spatially uneven. Temporally, land use development did not stabilized, and the two study periods of time （1985-1993 and 1993-2001） had different transition styles. Socioeconomic factors, such as gross domestic product, total population, and financial expenditure, were all highly correlated with the expansion of urban or built-up areas. Based on the degree of urban sprawl and socioeconomic factors, cities and towns were further divided into six subgroups, which may help decision makers improve land use for the region.

关键词： coastal region driving factors land use change urban sprawl

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顺德生态乐园之土壤及其合理利用建议

生态科学 2000年第3期19卷 79-88页

作者：夏汉平敖惠修何道泉刘世忠吕志林赵成武中国科学院华南植物研究所生态中心广东广州510650 广东省顺德生态乐园广东顺德528329

广东省顺德生态乐园内的土壤形成发育受气候、生物、地形地貌、母质母岩和人为干扰等 5大因素的影响 ,其中人为活动是导致土层结构破坏和水土流失的主要原因。酸度高、肥力低、土质较好是园内土壤的一个共同特征。在各类土壤中 ,坡地赤... 详细信息

广东省顺德生态乐园内的土壤形成发育受气候、生物、地形地貌、母质母岩和人为干扰等 5大因素的影响 ,其中人为活动是导致土层结构破坏和水土流失的主要原因。酸度高、肥力低、土质较好是园内土壤的一个共同特征。在各类土壤中 ,坡地赤红壤的面积最大 ,超过 70 % ,但坡顶土层瘠薄 ,水土流失较严重 ;坡麓和谷地由于冲积作用 ,往往形成相对较为深厚和肥力较高的土壤。水稻土有较长耕作历史 ,并已形成了潜育层和潴育层 ,但土壤肥力并不高。泥炭土有较高的有机质含量 ,但土壤过酸 ,速效养分含量过低 ,难以直接利用。因此 ,为能充分发挥土壤在园内的生态作用 ,在利用上做到因地制宜并采取一改土措施是十分必要的。

关键词：土壤调查土壤理化性状土壤改良顺德生态乐园

The effects of ion screening on neutrino-nucleus interactions in core-collapse supernova explosions

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Research in Astronomy and Astrophysics 2010年第7期10卷 689-695页

作者： Xiong-ping xia Lin Yi Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

The effects of ion screening in stellar core collapses are investigated based on a new progenitor star model. Simulation results show that ion screening slightly affects the leptons and decreases explosion energy, which is a negative factor for energy transfer supernova explosions. We also investigate the effect on type Ⅱ-supernova explosions of neutrino-nucleus elastic scattering based on the new progenitor star model. It is shown that, compared with the previously calculated results, neutrinos-nucleus elastic scattering in stellar core collapses is more severe, leading to an obvious reduction of the neutrino leakage energy loss and an increase of supernova explosion energy.

关键词： stars supernovae general -- neutrino-nucleus