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Distributed video coding with adaptive selection of hash functions

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第5期12卷 387-396页

作者： xin-hao CHEN Institute of Information and Communication Engineering Zhejiang UniversiO Hangzhou 310027 China Zhejiang Provincial Key Laboratory of Information Network Technology Hangzhou 310027 China

We address the compression efficiency of feedback-free and hash-check distributed video coding,which generates and transmits a hash code of a source information *** hash code helps the decoder perform a motion search.A hash collision is a special case in which the hash codes of wrongly reconstructed information sequences occasionally match the hash code of the source information *** deteriorates the quality of the decoded image *** this paper,the statistics of hash collision are analyzed to help the codec select the optimal trade-off between the probability of hash collision and the length of the hash code,according to the principle of rate-distortion ***,two novel algorithms are proposed:(1) the nonzero prefix of coefficients (NPC),which indicates the count of nonzero coefficients of each block for the second algorithm,and also saves 8.4% bitrate independently;(2) the adaptive selection of hash functions (AHF),which is based on the NPC and saves a further 2%-6% bitrate on *** detailed optimization of the parameters of AHF is also presented.

关键词： Hash Collision Distributed video coding Wyner-Ziv

Preface:Site testing campaign for the Large Optical/infrared Telescope of China

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Research in Astronomy and Astrophysics 2020年第6期20卷 79-80页

作者： Lu Feng Jin-xin hao National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

The Large Optical/infrared Telescope of China is a 12 meter diameter ground-based optical/infrared telescope which is proposed to be constructed in the western part of China in favor of its arid climate,and clear,dark nights.A site testing campaign was initiated between November 2016 and March2019 in order to investigate long term astronomical weather conditions in the western part of China,specifically,at three sites:Ali in Tibet,Daocheng in Sichuan and Muztagh-ata in *** is the first attempt to evaluate long term performances of three candidate sites with uniformly calibrated instruments and data collecting/processing methods for a two-year span in *** this special issue,we present nine papers that describe the whole site testing campaign,including preparation,data collecting/processing methods,instrument set up at three candidate sites as well as detailed statistics for the measurement results from March 2017 to March 2019.

关键词： telescopes-site testing-methods observational-instrumentation miscellaneous

Relativistic transformation of thermodynamic parameters and refined Saha equation

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Communications in Theoretical Physics 2023年第3期75卷 135-146页

作者： xin hao Shaofan Liu Liu Zhao College of Physics Hebei Normal UniversityShijiazhuang 050024China School of Physics Nankai UniversityTianjin 300071China

The relativistic transformation rule for temperature is a debated topic for more than 110 *** incompatible proposals exist in the literature but a final resolution is still *** this work,we reconsider the problem of relativistic transformation rules for a number of thermodynamic parameters including temperature,chemical potential,pressure,entropy and enthalpy densities for a relativistic perfect fluid using relativistic kinetic *** analysis is carried out in a fully relativistic covariant manner,and the explicit transformation rules for the above quantities are obtained in both Minkowski and Rindler *** results suggest that the temperature of a moving fluid appears to be colder,supporting the proposal by de Broglie,Einstein,and Planck,in contrast to other ***,in the case of a Rindler fluid,our findings suggest that the total number of particles and the total entropy of a perfect fluid in a box whose bottom is parallel to the Rindler horizon are proportional to the area of the bottom,but are independent of the height of the box,provided the bottom of the box is sufficiently close to the Rindler *** area dependence of the particle number implies that the particles tend to be gathered toward the bottom of the box,and hence implicitly determines the distribution of the chemical potential of the system,whereas the area dependence of the entropy indicates that the entropy is still additive and may have potential applications in explaining the area law of black hole *** a by-product,we also obtain a relativistically refined version of the famous Saha equation which holds in both Minkowski and Rindler spacetimes.

关键词： relativistic kinetic theory relativistic thermodynamics Saha equation

Damage evolution mechanism of rock-soil mass of bedrock and overburden layer slopes based on shaking table test

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Journal of Mountain Science 2022年第12期19卷 3645-3660页

作者： TONG xin-hao LIAN Jing ZHANG Liang School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China School of Civil Engineering Chongqing UniversityChongqing 400030China

This paper aims to investigate the seismic motion characteristics of bedrock and overburden layer slope with the prototype model taken from slopes in the Zheduo Mountain in Northwest Plateau of Sichuan Province,*** on dimensional analysis and similarity principle,two model tests with different slope angles were carried out.A transfer function analysis method was proposed to interpret the results from shaking table *** eliminating trend terms and signal filtering,the time-domain acceleration was transformed into frequency *** the transfer function was calculated by an average periodic *** variation of transfer function from different positions was analyzed by Pearson correlation coefficient,and the least square iteration method was used for modal *** effect of seismic intensity on the dynamic response was *** is found that the transfer function obviously changes when the slopes are *** from modal analysis show that the natural frequency decreases with the increase of the excitation intensity,and the damping ratio increases due to slope damage.

关键词： Seismic wave Shaking table test Seismic intensity Slope response Modal analysis Vibration

Numerical Study on Lateral Buckling Mode of Pipelines Laid on A Sleeper

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China Ocean Engineering 2023年第3期37卷 495-505页

作者： LIU Run hao xin-tong LI Cheng-feng YU Zheng LI Qing-xin State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

Because non-buried submarine pipelines under cyclic thermal loading are prone to global buckling,sleepers are commonly laid along the pipeline route to induce a series of relatively small and controllable lateral buckling.A finite element model which can simulate the transformation of pipeline laid on a sleeper from vertical buckling to lateral buckling is established in this *** parameters of sleeper affecting pipeline buckling modes are analysed,and a new kind of sleeper is proposed aimed at avoiding antisymmetric *** show that the lateral trigger force can avoid antisymmetric lateral buckling when acting between 1℃and 13℃before the critical buckling *** range increases slightly with increasing trigger *** with an ordinary sleeper,the proposed new sleeper with slider can reduce the critical buckling temperature by 25%,which significantly improves the success rate of sleepers.

关键词： submarine pipeline buckling mode initial imperfection new sleeper

Automatic mass segmentation on mammograms combining random walks and active contour

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第9期13卷 635-648页

作者： xin hao Ye SHEN Shun-ren XIA MOE Key Laboratory of Biomedical Engineering Zhejiang UniversityHangzhou 310027China Department of Signal and lnformation Processing China Jiliang UniversityHangzhou 310018China

Accurate mass segmentation on mammograms is a critical step in computer-aided diagnosis (CAD) systems. It is also a challenging task since some of the mass lesions are embedded in normal tissues and possess poor contrast or ambiguous margins. Besides, the shapes and densities of masses in mammograms are various. In this paper, a hybrid method combining a random walks algorithm and Chan-Vese (CV) active contour is proposed for automatic mass segmentation on mammograms. The data set used in this study consists of 1095 mass regions of interest (ROIs). First, the original ROI is preprocessed to suppress noise and surrounding tissues. Based on the preprocessed ROI, a set of seed points is generated for initial random walks segmentation. Afterward, an initial contour of mass and two probability matrices are produced by the initial random walks segmentation. These two probability matrices are used to modify the energy function of the CV model for prevention of contour leaking. Lastly, the final segmentation result is derived by the modified CV model, during which the probability matrices are updated by inserting several rounds of random walks. The proposed method is tested and compared with other four methods. The segmentation results are evaluated based on four evaluation metrics. Experimental results indicate that the proposed method produces more accurate mass segmentation results than the other four methods.

关键词： Active contour Random walks Mass segmentation Mammogram

Air target recognition method against ISRJ for radio frequency proximity sensors using chaotic stream encryption

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Defence Technology（防务技术） 2023年第10期28卷 267-279页

作者： Jian-feng Li Jian Dai xin-hong hao Xiao-peng Yan xin-wei Wang Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing100081China BIT Tangshan Research Institute Beijing100081China

The interrupted-sampling repeater jamming(ISRJ)can cause false targets to the radio-frequency proximity sensors(RFPSs),resulting in a serious decline in the target detection capability of the *** article proposes a recognition method for RFPSs to identify the false targets caused by *** proposed method is realized by assigning a unique identity(ID)to each RFPS,and each ID is a periodically and chaotically encrypted in every pulse *** processing technique of the received signal is divided into ranging and ID *** the ranging part,a high-resolution range profile(HRRP)can be obtained by performing pulse compression with the binary chaotic *** suppress the noise,the singular value decomposition(SVD)is applied in the *** ID decryption,targets and ISRJ can be recognized through the encryption and decryption processes,which are controlled by random *** adaptability analysis conducted in terms of the peak-to-side lobe ratio(PSLR)and bit error rate(BER)indicates that the proposed method performs well within a 70-k Hz Doppler shift.A simulation and experimental results show that the proposed method achieves extremely stable target and ISRJ recognition accuracies at different signal-to-noise ratios(SNRs)and jamming-to-signal ratios(JSRs).

关键词： Interrupted-sampling repeater jamming(ISRJ) Radio frequency proximity sensors(RFPS) Chaotic stream encryption Air target recognition Identity(ID)decryption

Fe_3O_4 nano-whiskers by ultrasonic-aided reduction in concentrated NaOH solution

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Particuology 2011年第1期9卷 86-90页

作者： Chenglong Yu xin hao Hongtao Jiang Lili Wang School of Materials Science and Engineering Shaanxi University of Science & Technology Xi'an 710021 China Research Laboratory of Hydrothermal Chemistry Faculty of Science Kochi University Kochi 7808520 Japan

Fe3O4 nano-whiskers were synthesized via ultrasonic-aided reduction of FeCl2.4H2O with N2H4-H2O in concentrated NaOH solution. Phase identification and morphology observation were conducted by X-ray diffraction （XRD） analysis, transmission electron microscopy （TEM） and field emission scanning electron microscopy （FE-SEM）. Face scanning energy dispersive spectrum （face scanning EDS） and twodimensional fast Fourier transform （2DFFF） for element distribution were carried out for confirming composition homogeneity. From XRD and TEIVI, the synthesized Fe304 nano-whiskers are of cubic phase with average dimension of 20 nm~ 200 nm （average aspect ratio of 10）. FE-SEM shows that the nanowhiskers without dispersion are interconnected into a network at a scale of 20μm. 2DFFT of the distribution of Fe and O from face scanning EDS confirms the composition homogeneity of the synthesized Fe3O4. Hydrazine hydrate determines the formation of the nano-whiskers, while the possible mechanism is the preferred growth along certain orientation with the aid of ultrasonic treatment.

关键词： Fe 3 O 4 nano-whiskers Morphology Homogeneity Two-dimensional fast Fourier transform

Bioinformatics analysis of structure and function in the MRP gene family and its expression in response to various drugs in Bursaphelenchus xylophilus

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Journal of Forestry Research 2021年第2期32卷 779-787页

作者： Jian Diao xin hao Wei Ma Ling Ma College of Forestry Northeast Forestry UniversityHarbin 150040People’s Republic of China Heilongjiang University of Chinese Medicine Harbin 150000People’s Republic of China

Genes homologous to members of the MRP gene family in Caenorhabditis elegans are important in drug *** further explore the molecular mechanism of drug resistance in pine wood nematode(Bursaphelenchus xylophilus),we used bioinformatics approaches to analyze genomic data for *** and identified Bx-MRP *** predicted the structure and function of the genes and encoded *** bioinformatics programs to predict and analyze various properties of the predicted proteins,including hydrophobicity,transmembrane regions,phosphorylation sites,and topologically isomeric structures,of these Bx-MRP genes,we determined that they function in transmembrane *** the results of RT-qPCR,the Bx-MRP family members confer significant differential resistance to different drug *** treatment with different concentrations of emamectin benzoate,avermectin and matrine,the expression of each gene increased with increasing drug concentrations,indicating that the family members play a positive role in the regulation of multidrug resistance.

关键词： Bursaphelenchus xylophilus Bx-MRP gene family Gene and protein structure Bioinformatics Multidrug stress