检索结果-南通市图书馆

Acta Mathematicae Applicatae Sinica 2021年第2期37卷 393-408页

作者： de-qiang zheng Xiang-zhong FANG School of Mathematical Sciences Peking UniversityBejing 100871China

Life data frequently arise in many reliability studies,such as accelerated life tests *** paper considers the part of life data where failure and censoring observations may *** develop statistical methods and theory for the analysis of these data,a new approach was proposed to obtain the exact lower and upper confidence limits for the mean life of the exponential distribution with Type-I censoring *** is assumed that the acceleration factor is a random variable,and that the distribution of the acceleration factor is known from some empirical information or the meta analysis.A method for constructing the lower and upper confidence limits for the parameter based on an ordering relation among the sample space was *** studies and analyses of two examples suggest that the proposed method performed well.

关键词： mean life confidence limit acceleration factor sample space ordering relation

Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing

在线全文

学校读者我要写书评

暂无评论

Atmospheric and Oceanic Science Letters 2025年第1期18卷 39-45页

作者： Haolan Ren Fei zheng Tingwei Cao qiang Wang International Center for Climate and Environment Science(ICCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina College of Oceanography Hohai UniversityNanjingChina CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences and Pilot National Laboratory for Marine Science and Technology(Qingdao)QingdaoChina

Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate *** studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC *** this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its *** a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s *** traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of *** results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter ***,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale.

关键词： Recovery of AMOC 4×CO_(2)forcing Key parameter Parameter estimation Data assimilation Machine learning

在线全文

学校读者我要写书评

暂无评论

大采深巷道围岩变形特征及控制技术研究

山东煤炭科技 2017年第9期35卷 12-14页

作者：赵德强郑元忠兖州煤业鄂尔多斯能化有限公司内蒙古鄂尔多斯017010 济南贝克矿山工程技术服务有限公司山东济南250031

基于地应力实测结果采用大型岩土类三维分析软件3D-FSM DDM间接边界元数值系统,分析了西部大采深巷道围岩应力演化及其变形破坏规律,并在深知西部大采深巷道围岩变形原因及其破坏根源的基础上,进一步探求高地应力条件下西部大采深巷道... 详细信息

基于地应力实测结果采用大型岩土类三维分析软件3D-FSM DDM间接边界元数值系统,分析了西部大采深巷道围岩应力演化及其变形破坏规律,并在深知西部大采深巷道围岩变形原因及其破坏根源的基础上,进一步探求高地应力条件下西部大采深巷道围岩稳定性控制对策。

关键词：大采深围岩变形控制

Comprehensive bibliometric analysis of pharmacotherapy for bipolar disorders:Present trends and future directions

在线全文

学校读者我要写书评

暂无评论

World Journal of Psychiatry 2025年第1期15卷 153-167页

作者： Bo-Fan Chen Li Liu Fang-Zhen Lin Hai-Min Zeng Hai-qiang Huang Chun-Fang Zhang Cong-Cong Liu Xiang Chen Jie Peng Yun-Fa Wang Zhi-Lin Wang Bin Chen de-Le Liu Yun Liu zheng-zheng Li Xin-Xing Zeng The Second Affiliated Hospital Jiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina The Second Clinical Medical College Jiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina department of Rehabilitation Medicine The Second Affiliated HospitalJiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina Jiangxi Provincial People’s Hospital The First Affiliated Hospital of Nanchang Medical CollegeNanchang 330006Jiangxi ProvinceChina department of Psychiatry Jiangxi Mental HospitalHospital of Nanchang UniversityNanchang UniversityNanchang 330029Jiangxi ProvinceChina

BACKGROUND Bipolar disorder(BD)is a severe mental illness characterized by significant mood *** drug treatment modalities are crucial for managing *** To analyze the current status and future trends of global research on BD drug treatment over the last *** The Web of Science Core Collection database spanning from 2015 to 2024 was utilized to retrieve literature related to BD drug treatment.A total of 2624 articles were *** visualization and analysis were conducted using CiteSpace,VOSviewer,Pajek,Scimago Graphica,and R-studio bibliometrix to identify RESULTS The United States,China,and the United Kingdom have made the most significant contributions to research on BD drug treatment and formed notable research collaboration *** University of Pittsburgh,Massachusetts General Hospital,and the University of Michigan have been identified as the major research institutions in this *** Journal of Affective Disorders is the most influential journal.A keyword analysis revealed research hotspots related to clinical symptoms,drug efficacy,and genetic mechanisms.A citation analysis identified the management guidelines published by Yatham et al in 2018 as the most cited *** This study provides a detailed overview of the field of BD drug treatment,highlighting key contributors,research hotspots,and future *** study findings can be employed as a reference for future research and policymaking,which may enable further development and optimization of BD pharmacotherapy.

关键词： Bipolar disorder Drug treatment Bibliometric analysis Visualization Mental disorder

The defocusing Energy-supercritical Hartree Equation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2014年第4期30卷 547-566页

作者： Ji qiang zheng The Graduate School of China Academy of Engineering Physics

In this paper, we study the global well-posedness and scattering problem for the energy -supercritical Hartree equation iut ＋ △u - （｜χ｜^-r＊｜u｜^2）u = 0 with r〉 4 in dimension d 〉r. We prove that if the solution u is apriorily bounded in the critical Sobolev space, that is, u ∈ Lt^∞（I;Hx^sc（R^d）） with Sc ：= x/2 - 1 〉 1, then u is global and scatters. The impetus to consider this problem stems from a series of recent works for the energy-supercritical nonlinear wave equation （NLW） and nonlinear SchrSdinger equation （NLS）. We utilize the strategy derived from concentration compactness ideas to show that the proof of the global well-posedness and scattering is reduced to disprove the existence of three scenarios： finite time blowup; soliton-like solution and low to high frequency cascade. Making use of the No-waste Duhamel formula, we deduce that the energy of the finite time blow-up solution is zero and so get a contradiction. Finally, we adopt the double Duhamel trick, the interaction Morawetz estimate and interpolation to kill the last two scenarios.

关键词： Havtree equation scattering theory Strichartz estimate energy supercritical concentration compactness

Effect of Phase Noise on the Stationary Entanglement of an Optomechanical System with Kerr Medium

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2013年第2期30卷 143-146页

作者： ZHANG Dan zheng qiang School of Chemistry and Material Science Guizhou Normal UniversityGuiyang 550001 School of Mathematics and Computer Science Guizhou Normal UniversityGuiyang 550001

We theoretically investigate the effect of phase noise on the stationary entanglement of an optomechanical system,which has the additional Kerr medium in the *** are two kinds of interactions in the system,photon-mirror interaction and photon-photon *** find that the optomechanical entanglement can be suppressed by the phase noise of the pumping laser and Kerr interaction of *** also find that Kerr interaction can make the phase-noise-induced double peak of the stationary entanglement change to a single peak.

关键词： interaction. stationary interaction

Cross-linking density and aging constitutive model of HTPB coating under prestrain thermal accelerated aging

在线全文

学校读者我要写书评

暂无评论

defence Technology（防务技术） 2020年第2期16卷 439-446页

作者： Yong-qiang Du Jian zheng Chao Xiong Shijiazhuang Campus Army Engineering UniversityShijiazhuang 050003China

In order to study the cross-linking density and aging constitutive relationship of HTPB coating during storage,the thermal accelerated aging tests at 0%,3%,6%and 9%prestrains were carried *** crosslinking density of HTPB coating at different aging stages were tested using low-field^1 H NMR and the variation of cross-linking density was *** aging model of cross-linking density considering the chemical aging and the physical stretching factors was *** uniaxial tensile tests were carried out on HTPB coating at different aging stages and the cross-linking density was introduced into Ogden hyperelastic constitutive model as a characterization parameter of correction *** with uniaxial tensile test results,a prestrain aging constitutive model of HTPB coating was *** results show that the cross-linking density of HTPB coating increases rapidly at first and then slowly with the increase of thermal accelerated aging time without *** prestrain conditions,the crosslinking density of HTPB coating decreases at the early stage,and increases rapidly at first and then slowly at the middle and late stages of thermal accelerated *** correlation coefficients of aging model of cross-linking density and aging constitutive model with test results are R>0.9500 and R>0.9900 respectively,which can be used to accurately describe the cross-linking density and aging constitutive relationship of HTPB coating under prestrain accelerated thermal aging conditions.

关键词： Prestrain thermal accelerated aging Low-field^1H NMR Cross-linking density Aging constitutive model

Dynamics of Bose-Einstein condensates in a one-dimensional optical lattice with double-well potential

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2013年第4期8卷 375-380页

作者： Han-Lei zheng qiang Gu department of Physics University of Science and Technology Beijing Beijing 100083 China

We study dynamical behaviors of the weakly interacting Bose-Einstein condensate in the one- dimensional optical lattice with an overall double-well potential by solving the time-dependent Gross-Pitaevskii equation. It is observed that the double-well potential dominates the dynamics of such a system even if the lattice depth is several times larger than the height of the double-well potential. This result suggests that the condensate flows without resistance in the periodic lattice just like the case of a single particle moving in periodic potentials. Nevertheless, the effective mass of atoms is increased, which can be experimentally verified since it is connected to the Josephson oscillation frequency. Moreover, the periodic lattice enhances the nonlinearity of the double-well condensate, making the condensate more ＂self-trapped＂ in the ^-mode self-trapping regime.

关键词： Bose-Einstein condensate double-well potential optical lattice dynamical behavior

Approaching Quantum-Limited Amplification with Large Gain Catalyzed by Optical Parametric Amplifier Medium

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2017年第7期67卷 76-82页

作者： qiang zheng Kai Li School of Mathematics Guizhou Normal University Guiyang 550025 China Beijing Computational Science Research Center Beijing 100193 China

Amplifier is at the heart of experiments carrying out the precise measurement of a weak signal. An idea quantum amplifier should have a large gain and minimum added noise simultaneously. Here, we consider the quantum measurement properties of the cavity with the OPA medium in the op-amp mode to amplify an input signal. We show that our nonlinear-cavity quantum amplifier has large gain in the single-value stable regime and achieves quantum limit unconditionally.

关键词： amplifier op-amp mode OPA quantum limit

Bowel preparation before colonoscopy: Consequences, mechanisms, and treatment of intestinal dysbiosis

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2025年第2期31卷 13-26页

作者： Ze-Long zheng Qing-Fan zheng Li-qiang Wang Yi Liu department of Gastroenterology(Endoscopy Center) China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina

The term“gut microbiota”primarily refers to the ecological community of various microorganisms in the gut,which constitutes the largest microbial community in the human *** adequate bowel preparation can improve the results of colonoscopy,it may interfere with the gut *** preparation for colonoscopy can lead to transient changes in the gut microbiota,potentially affecting an individual’s health,especially in vulnerable populations,such as patients with inflammatory bowel ***,measures such as oral pro-biotics may ameliorate these adverse *** focused on the bowel prepa-ration-induced changes in the gut microbiota and host health status,hypothesized the factors influencing these changes,and attempted to identify measures that may reduce dysbiosis,thereby providing more information for individualized bowel preparation for colonoscopy in the future.

关键词： Bowel preparation Colonoscopy Microbiota Inflammatory bowel disease Probiotics