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Singularity Detection of Signals Based on their Wavelet Transform

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The Journal of China Universities of Posts and Telecommunications 2000年第3期7卷 12-16页

作者： zheng ji ming (Chongqing University of Posts and Telecommunications, Chongqing 400065,P.R. China) Chongqing University of Posts and Telecommunications Chongqing 400065 P.R. China

This paper introduces a multiresolution decomposition of signals based on their wavelet transform. The different behaviors of the wavelet transform between the signal and the noise are compared. An algorithm of singul... 详细信息

关键词： wavelet transform Lipschitz exponents, singularity detection

Nanoindentation behavior and creep-induced cracking of long-term crept austenitic steel at 650℃

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Journal of Iron and Steel Research International 2024年第2期31卷 464-474页

作者： Zhen Zhang Yu-hang Duan Shuai Wang jin-shan Chen An-zhe Wang Xiang-yang Mao Yuan-ji Shi jie Zhang ming Liu zheng-fei Hu School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing211167JiangsuChina jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing211167JiangsuChina jiangsu Wind Power Engineering Technology Center Nanjing210023JiangsuChina Nanjing Vocational University of Industry Technology Nanjing210023JiangsuChina Baoshan Iron&Steel Co. Ltd.Shanghai201900China Fujian Provincial Key Laboratory of Terahertz Functional Devices and Intelligent Sensing School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116FujianChina School of Materials Science and Engineering Tongji UniversityShanghai201804China

The grain boundary(GB)damage of long-term crept HR3C(25Cr–20Ni–Nb–N)austenitic steel with solid solution state was investigated by nanoindentation test accompanied with in-situ electron back-scattered *** corresponding microstructure was characterized by scanning electron microscopy and transmission electron *** show that the increase in nanoindentation hardness at the GBs and triple grain junctions may be related to the dislocation accumulation and carbide growth during the *** M23C6 and dislocations piling-up at the GB accelerate the nucleation and coalescence of creep cavity along the *** nanoindentation hardness in grains varies with orientation of the stress *** orientation difference of neighbor grains may induce local high geometrically necessary dislocation densities and strain gradients near the GB,consequently causing stress concentration and subsequent crack growth at specific GBs.

关键词： Austenitic steel Creep Nanoindentation Grain orientation Creep-induced cracking

Drug-Target Interactions Prediction Based on Signed Heterogeneous Graph Neural Networks

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Chinese Journal of Electronics 2024年第1期33卷 231-244页

作者： ming CHEN Yajian jiANG Xiujuan LEI Yi PAN Chunyan ji Wei jiANG College of Information Science and Engineering Hunan Normal University School of Computer Science Shaanxi Normal University Faculty of Computer Science and Control Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences Computer Science Department BNU-HKBU United International College

Drug-target interactions(DTIs) prediction plays an important role in the process of drug *** computational methods treat it as a binary prediction problem, determining whether there are connections between drugs and targets while ignoring relational types information. Considering the positive or negative effects of DTIs will facilitate the study on comprehensive mechanisms of multiple drugs on a common target, in this work, we model DTIs on signed heterogeneous networks, through categorizing interaction patterns of DTIs and additionally extracting interactions within drug pairs and target protein pairs. We propose signed heterogeneous graph neural networks(SHGNNs), further put forward an end-to-end framework for signed DTIs prediction, called SHGNN-DTI,which not only adapts to signed bipartite networks, but also could naturally incorporate auxiliary information from drug-drug interactions(DDIs) and protein-protein interactions(PPIs). For the framework, we solve the message passing and aggregation problem on signed DTI networks, and consider different training modes on the whole networks consisting of DTIs, DDIs and PPIs. Experiments are conducted on two datasets extracted from Drug Bank and related databases, under different settings of initial inputs, embedding dimensions and training modes. The prediction results show excellent performance in terms of metric indicators, and the feasibility is further verified by the case study with two drugs on breast cancer.

关键词： Drugs Training Proteins Measurement Message passing Prediction methods Graph neural networks

Postpartum depression and partner support during the period of lactation:Correlation research and its influencing factors

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World Journal of Psychiatry 2024年第1期14卷 119-127页

作者： ji-ming Ruan Ling-Juan Wu Department of Obstetrics and Gynecology Huzhou Maternity and Child Health Care HospitalHuzhou 313000Zhejiang ProvinceChina

BACKGROUND Postpartum depression(PPD)not only affects the psychological and physiological aspects of maternal health but can also affect neonatal growth and *** who are in close contact with parturient women play a key role in communication and emotional *** study explores the PPD support relationship with partners and its influencing factors,which is believed to establish psychological well-being and improve maternal partner *** To explore the correlation between PPD and partner support during breastfeeding and its influencing *** Convenience sampling was used to select lactating women(200 women)who underwent postpartum examinations at the Huzhou Maternity and Child Health Care Hospital from July 2022 to December 2022.A cross-sectional survey was conducted on the basic information(general information questionnaire),depression level[edinburgh postnatal depression scale(EPDS)],and partner support score[dyadic coping inventory(DCI)]of the selected ***’s correlation analysis was used to analyze the correlation between PPD and DCI in lactating *** affecting PPD levels during lactation were analyzed using multiple linear *** The total average score of EPDS in 200 lactating women was(9.52±1.53),and the total average score of DCI was(115.78±14.90).Dividing the EPDS,the dimension scores were:emotional loss(1.91±0.52),anxiety(3.84±1.05),and depression(3.76±0.96).Each dimension of the DCI was subdivided into:Pressure communication(26.79±6.71),mutual support(39.76±9.63),negative support(24.97±6.68),agent support(6.87±1.92),and joint support(17.39±4.19).Pearson’s correlation analysis demonstrated that the total mean score and individual dimension scores of EPDS during breastfeeding were inversely correlated with the total score of partner support,stress communication,mutual support,and cosupport(P<0.05).The total mean score of the EPDS and its dimensions were positively correlated with negative

关键词： Lactation period Puerpera Postpartum depression Partner support Correlation

Thermal stability of permafrost under U-shaped crushed rock embankment of the Qinghai-Tibet Railway

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Advances in Climate Change Research 2024年第1期15卷 158-169页

作者： Kun-ming XU Guan-Li jiANG ji CHEN Qing-Bai WU State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Beiluhe Observation Station of Frozen Soil Environment and Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China

The U-shaped crushed rock embankment(UCRE),of which widely utilized in the permafrost regions along the Qinghai-Tibet Railway,has the capability to rapidly reduce the ground temperature of the underlying ***,there remains uncertainty regarding the adaptation of UCRE to climate change and its long-term cooling *** study focuses on nine UCRE monitoring sites along the Qinghai-Tibet Railway to analyze the dynamic variations of the ground temperature underlying permafrost from 2006 to *** efficiency of UCRE in stabilizing permafrost temperature in different permafrost zones is evaluated by considering the permafrost table,ground temperature,and MAGT,as well as the temperature difference between the top and bottom of the crushed rock layer and the ground temperature variation index(GTVI).The results show that UCRE is suitable for application in extremely unstable warm permafrost regions where the MAGT is higher than-0.5℃.Moreover,UCRE effectively diminishes the disparity in permafrost thermal stability between the sunny and shaded shoulders of the *** short-term and long-term effect of cooling permafrost is experiencing a change related with permafrost ***,in stable cold permafrost regions with MAGT lower than-1.5℃,the long-term cooling effect of UCRE on permafrost seems to gradually di-minishes,but UCRE continues to fulfill the role of stabilizing the underlying permafrost thermal state over the *** results show that UCRE can quickly restore and stabilize the thermal state of permafrost in the early stages of construction,and adapt to the influence of future climate *** findings provide important guidance for understanding the variations of permafrost thermal stability beneath the embankment in permafrost regions,as well as for improving the embankment stability and operational safety of the Qinghai-Tibet Railway.

关键词： Qinghai-Tibet Railway U-shaped crushed rock embankment Climate change Permafrost zone Ground temperature variation index Long-term coolingrole

具有时滞的奇异扰动随机微分方程的均方指数稳定性(英文)

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应用数学 2008年第2期21卷 373-377页

作者：郑继明重庆邮电大学应用数学研究所重庆400065

本文利用常数变易公式,随机过程数学期望的性质,矩阵范数,测度的相关理论以及不等式技巧,对一类具有时滞的奇异扰动随机微分方程的均方指数稳定性进行了讨论,得到了该类方程均方指数稳定的充分条件的代数判据.

关键词：指数稳定性奇异扰动随机性时滞矩阵测度

Enhanced thermoelectric and mechanical properties of Bi_(0.5)Sb_(1.5)Te_(3) alloy with dispersed yttrium oxide ceramic nanoparticles

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Rare Metals 2024年第4期43卷 1758-1768页

作者： Cun-Cheng Li ming-Wei Zhang ji-Wu Xin Lei Wei Wen-Yu Zhao School of Materials Science and Engineering Shandong University of TechnologyZibo255000China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore639798Singapore State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China

Reducing thermal conductivity while avoiding adverse interfacial reactions during sintering is crucial for improving the thermoelectric performance of Bi_(2)Te_(3)based *** ceramic nanoparticles are good candidates for achieving this *** this study,we designed and prepared a series of p-type Bi_(0.5)Sb_(1.5)Te_(3)nanocomposites decorated with Y_(2)O_(3)ceramic nanoparticles via ball-milling dispersion and spark-plasma *** to the chemical stability of the ceramics,no traces of atomic doping or interfacial reactions were *** measurements revealed that the Y_(2)O_(3)nanoparticles distributed along the grain boundaries acted as energy-dependent carrier-filtering centers to improve the scattering parameter and Seebeck coefficient,contributing to the elevated power factor even with a decreased electrical ***,the incorporated Y_(2)O_(3)nanoparticles and various defect structures they induced effectively strengthened the phonon scattering and suppressed the lattice thermal ***,a peak figure of merit(ZT)of 1.23 at 313 K was achieved for 0.4%Y_(2)O_(3)/Bi_(0.5)Sb_(1.5)Te_(3),which is 13%higher than that of the *** addition,the Vickers hardness of the composite material was 35%higher than that of the *** study demonstrates the effectiveness of ceramic nanoparticles in synergistic ally improving the thermoelectric and mechanical properties,which may be further extended to other thermoelectric systems.

关键词： Bi_(0.5)Sb_(1.5)Te_3 alloy Y_(2)O_(3) ceramic nanoparticles Microstructures Thermoelectric performance Mechanical properties

Isocyanide-Based One-Pot Cascade Synthesis of 3-Acyl Isoindolinones

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Chinese Journal of Chemistry 2024年第3期42卷 259-263页

作者： jia Liu Yi-ming Zhu Xiao-Ping Xu Shun-Jun ji Key Laboratory of Organic Synthesis of jiangsu Province College of ChemistryChemical Engineering and Materials Science & Collaborative Innovation Center of Suzhou Nano Science and TechnologySoochow UniversitySuzhouJiangsu215123 China Suzhou Baolidi Functional Materials Research Institute SuzhouJiangsu215144 China

A series of 3-acyl-substituted isoindolinone derivatives were synthesized in a one-pot manner via the reaction of o-bromobenzaldehydes,isocyanides,and carboxylic acids in the presence of palladium catalyst and base. The reaction employing easily available starting materials features simple operation and high efficiency. The mechanistic study showed that the reaction might undergo 1) Pd-catalyzed [3+2] cyclization of o-bromobenzaldehyde with isocyanide and the re-insertion of another molecule of isocyanide,2) addition of carboxylic acid to in situ formed ketenimine followed by a rearrangement relay to give 3,3-diacyl-substituted isoindolinone derivative. Further transformations of the obtained products through decarbonylation could also be realized.

关键词： One-pot reaction Isocyanide Pd catalysis Rearrangement reaction Isoindolinone

Research on the Encapsulation Device for Lunar Samples

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 104-117页

作者： Yonggang Du Chunyong Wang Haoling Li Ying Zhou ming ji Xuesong Wang Lanzhou Institute of Physics CASTLanzhou 730000China

The encapsulation of lunar samples is a core research area in the third phase of the Chinese Lunar Exploration *** seal assembly,opening and closing mechanism(OCM),and locking mechanism are the core components of the encapsulation device of the lunar samples,and the requirements of a tight seal,lightweight,and low power make the design of these core components *** this study,a combined sealing assembly,OCM,and locking mechanism were investigated for the *** sealing architecture consists of rubber and an Ag-In alloy,and a theory was built to analyze the *** of the electroplate Au coating on the knife-edge revealed that the hermetic seal can be significantly *** driving principle for coaxial double-helical pairs was investigated and used to design the ***,a locking mechanism was created using an electric initiating explosive device with orifice *** optimizing the design,the output parameters were adjusted to meet the requirements of the lunar *** experimental results showed that the helium leak rate of the test pieces were not more than 5×10^(-11) Pa·m^(3)·s^(-1),the minimum power of the OCM was 0.3 W,and the total weight of the principle prototype was 2.9 *** explosive driven locking mechanism has low *** investigation solved the difficulties in achieving tight seal,light weight,and low power for the lunar explorer,and the results can also be used to explore other extraterrestrial objects in the future.

关键词： Lunar samples Encapsulation Vacuum seal Mechanism