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Effect of Increase in Price of Oil on Behavior of Private Car Owners in Beijing

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Chinese Journal of Population,Resources and Environment 2010年第1期8卷 55-61页

作者： Yi ru zhang Shiqiu College of Environmental Science and Engineering Peking University Beijing 100871 China

In order to understand the short-term response of private car owners to changes in the price of oil,a survey was conducted in Beijing after the gasoline price in China rose in June *** showed that private car drivers in Beijing reduced their trips in the one month period following the price *** trip characteristics and drivers' demographics significantly influenced price elasticity in the short term,including the purpose of the trip,the distance covered and the income of the car driver.

关键词： price elasticity private car travel behavior

Growth-inhibiting effects of taxol on human liver cancer in vitro and in nude mice

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World Journal of Gastroenterology 2000年第2期6卷 210-215页

作者： Jin Hui Yuan ru Ping zhang ru Gang zhang Li Xia Guo Xing Wang Wang Dan Luo Yong Xie Hong Xie Shanghai Institute of Cell Biology Chinese Academy of SciencesShanghai 200031China Hong Kong University of Science and Technology Hong KongChina

AIM To investigate the effects of taxol onSMMC-7721 human hepatoma and *** In vitro cell growth was assessedby trypan blue exclusion *** model was established by seedingSMMC-7721 cells subcutaneously into Balb/c(nu/nu)nude *** vivo tumor growth wasdetermined by measurement of tumor diameterwith Vernier *** syntheses of DNA,RNA and protein were analyzed by incorporationof ~3H-thymidine,~3H-uridine and ~*** light and electronmicroscopes to observe the morphologicalchanges of cells including mitosis *** Taxol was effective against SMMC-7721 human hepatoma cell growth in the rangesof 2.5 nmol/L-10 nmol/L with mitotic arrestand apoptosis in ***,RNA and proteinsyntheses in cells were also obviouslysuppressed by in vitro treatment of taxol for72 *** at 2.5 nmol/L reduced ~3H-thymidineuptake to about 34% of the control value(P<0.05).Increasing the dose of taxol to20 nmol/L resulted in a greater decrease in ~3H-thymidine incorporation to 60% of the controlvalue(P<0.01).At a concentration of 20 nmol/L,the ~3H-uridine and ~3H-leucine uptakeswere reduced to 52%(P<0.05)and 63%(P<0.01),*** vivo,taxolsignificantly inhibited SMMC-7721 tumor growthat 10 mg/kg,i.p.,once daily for 10 d.A morethan 90% decrease in tumor volume wasobserved by day 11(P<0.01)similarly withmitotic arrest and cell *** Taxol has a marked anticanceractivity in SMMC-7721 human hepatoma both invitro and in nude *** mechanisms might beassociated with mitotic arrest,subsequently,apoptosis of the hepatoma *** obvioustoxicity was observed with in vivoadministration of taxoi.

关键词： paclitaxel liver neoplasms apoptosis mitoics in vitro DNA RNA microscopy wection mice nude

204例社区获得性肺炎患者中医证素特征及其与病程的相关性研究

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现代中医临床 2024年第1期31卷 64-68页

作者：张妍张茹王嘉伟梁枫荻张京轩周滔北京中医药大学北京100029 北京中医药大学东方医院

目的探讨社区获得性肺炎(CAP)患者中医证素特征及其与病程的相关性。方法采集204例CAP患者的一般资料、中医四诊信息,按照“证候辨证素量表”各症状对应的证素积分,将每个证候所提示的相同证素权值进行加权求和。结果 204例患者中,证... 详细信息

目的探讨社区获得性肺炎(CAP)患者中医证素特征及其与病程的相关性。方法采集204例CAP患者的一般资料、中医四诊信息,按照“证候辨证素量表”各症状对应的证素积分,将每个证候所提示的相同证素权值进行加权求和。结果 204例患者中,证素积分≥70的病位证素共13个,表证素和肺证素频次最高,分别为163次(占79.9%)和95次(占46.6%)。证素积分≥70的病性证素共13个,前3位分别是外风证素(89次,占46.3%)、热证素(43次,占21.1%)和寒证素(32次,占15.7%)。病位证素中,表证素在不同病程的分布,差异具有统计学意义(χ~2=22.715,P<0.05)。病性证素中,寒证素在不同病程的分布,差异具有统计学意义(P<0.05)。病位证素中,表证素、肺证素以Ⅰ级(轻度病变)、Ⅱ级(中度病变)为主,心证素以Ⅰ级(轻度病变)为主。病性证素中,外风证素、热证素、寒证素、湿证素、痰证素均以Ⅰ级(轻度病变)为主。表证素等级与病程的相关性具有统计学意义,似然比检验结果χ~2=31.759(P<0.05)。结论 CAP患者中医证素分布具有一定的特征,表证素、寒证素与病程有显著相关性。

关键词：社区获得性肺炎证素病程

Speech Suppression with EEMD_WP

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Journal of Harbin Institute of Technology(New Series) 2013年第1期20卷 123-128页

作者： Xin-Yu zhang Xue-Yao Li ru-Bo zhang College of Computer Science and Technology Harbin Engineering University School of Management Harbin University of Commerce

In non-cooperation communication, speech suppression is an important link of aircraft type recognition based on shortwave speech communication. Ensemble mean and ensemble variance for analyzing physical characteristics of aircraft cockpit background sound has been proposed in this paper. Some important peak feature is revealed from the ensemble mean and ensemble variance, which has important guiding significance to further researches on speech suppression of aircraft type recognition based on shortwave speech communication. The two algorithms of speech suppression are proposed which are empirical mode decomposition and wavelet transform(EMD_WT) and the algorithm of ensemble empirical mode decomposition and wavelet packet (EEMD_WP). In the process of speech suppression, EMD_WT produced extra noise pollution, and EEMD_WP kept the aircraft cockpit background sound and weakened the effect of the speech largely. The contrast test proves that EEMD_WP has better performance by in time domain and in frequency domain.

关键词： speech suppression ensemble mean wavelet packet shortwave communication

图像分割述评:基本概貌、典型算法及比较分析

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计算机技术与发展 2024年第1期34卷 1-8页

作者：张婧张策张茹王宇彬张展苏子旸吕为工哈尔滨工业大学(威海)计算机科学与技术学院山东威海264209 哈尔滨商业大学管理学院黑龙江哈尔滨150076 哈尔滨工业大学计算机科学与技术学院黑龙江哈尔滨150001

图像分割作为计算机视觉领域的一个重要分支,在可穿戴计算、自动驾驶、医学图像分析等方面都发挥着重要作用,并有着广泛应用。为了更好地了解图像分割领域的发展以及研究现状,该文对图像分割进行了深入梳理和系统述评。首先,对图像分割... 详细信息

图像分割作为计算机视觉领域的一个重要分支,在可穿戴计算、自动驾驶、医学图像分析等方面都发挥着重要作用,并有着广泛应用。为了更好地了解图像分割领域的发展以及研究现状,该文对图像分割进行了深入梳理和系统述评。首先,对图像分割的含义以及其工作流程、指标等进行阐释;然后,对图像分割方法按照时间的跨度进行分类——基于阈值和区域、基于图论和聚类,以及基于深度学习的图像分割,对每类方法的代表性算法进行分析介绍,较为全面地总结了每类方法的基本思想和优缺点;最后,对该领域目前存在的问题和未来的发展方向进行展望,提出实时图像语义分割、弱监督或非监督语义分割和三维场景的语义分割是目前研究中的主要挑战。

关键词：图像分割分割算法语义分割深度学习像素分类

Design and development of the deep-rock in-situ condition-preserved coring calibration platform

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International Journal of Mining Science and Technology 2023年第11期33卷 1377-1395页

作者： Yihang Li Heping Xie ru zhang Zetian zhang Zhilong zhang Heng Gao Wei Huang Jixun zhang Jiming Gao Xin Ma ruibing Xu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Deep Underground Engineering Sciences and Green Energy Shenzhen UniversityShenzhen 518060China School of Mechanical Engineering Sichuan UniversityChengdu 610065China Donghua Zhuoyue Technology Co. Ltd.Chengdu 611130China Special Equipment Safety Supervision Inspection Institute of Jiangsu Province Nanjing 210036China Inner Mongolia North Heavy Industries Group Co. Ltd.Baotou 014033China

To systematically validate and calibrate the theory and technology of the deep in-situ conditionpreserved coring, the in-situ conditions at different depths should be simulated, and the full-size coring tests should be carried out in this simulated environment. Therefore, a deep-rock in-situ conditionpreserved coring calibration platform was designed and developed. The self-tightening sealing structure and the quick-disassembly structure were designed on the basis of an innovative segmented nonuniformdiameter structure, which was a breakthrough from the traditional high-pressure vessel frame and was verified by finite element simulation and actual testing under extreme working conditions, *** simulate the actual deep in-situ environment with a temperature of 150℃ and pressure of 140 MPa for a large Φ450 mm×H1400 mm core, temperature and pressure control systems were designed by coupling, and a pre-embedded high-pressure-resistant temperature sensor was designed. Finally, highprecision assembly automation, complex movement coordination of the coring device with the platform,and rotary dynamic sealing were achieved by utilizing the combination of adaptive cabin body servo control and an adaptive mechanical structure in a limited space, laying a solid foundation for the calibration of in-situ condition-preserved coring.

关键词： In-situ condition-preserved coring calibration Deep Earth science Coring simulation Rotary dynamic seal

Space-time evolution rules of acoustic emission location of unloaded coal sample at different loading rates

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International Journal of Mining Science and Technology 2012年第6期22卷 847-854页

作者： Ai Ting zhang ru Liu Jianfeng Ren Li State Key Laboratory of Hydraulic and Mountain River Engineering School of Water Resource and HydropowerSichuan University Department of Mechanics and Engineering Science Sichuan University

By using MTS815 rock mechanics test system,a series of acoustic emission(AE) location experiments were performed under unloading confining pressure,increasing the axial *** AE space-time evolution regularities and energy releasing characteristics during deformation and failure process of coal of different loading rates are compared,the influence mechanism of loading rates on the microscopic crack evolution were studied,combining the AE characteristics and the macroscopic failure modes of the specimens,and the precursory characteristics of coal failure were also analyzed *** results indicate that as the loading rate is higher,the AE activity and the main fracture will begin *** destruction of coal body is mainly the function of shear strain at lower loading rate and tension strain at higher rate,and will transform from brittleness to ductility at critical *** the deformation of the coal is mainly plasticity,the amplitude of the AE ringing counting rate increases largely and the AE energy curves appear an obvious ''step'',which can be defined as the first failure precursor *** of AE information shows that the strongest AE activity begins when the axial stress level was 92-98%,which can be defined as the other failure precursor *** the loading rate is smaller,the coal more easily reaches the latter precursor point after the first one,so attention should be aroused to prevent dynamic disaster in coal mining when the AE activity reaches the first precursor point.

关键词： Acoustic emission testing Acoustic emissions Coal Coal mines Deformation Disaster prevention Fracture mechanics Rock mechanics Shear strain Strain rate Unloading

Associations between the physical environment and park-based physical activity:A systematic review

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Journal of Sport and Health Science 2019年第5期8卷 412-421页

作者： ru zhang Hagen Wulff Yanping Duan Petra Wagner Department of Sport and Physical Education Faculty of Social SciencesHong Kong Baptist UniversityHong Kong 999077China Institute of Exercise and Public Health Faculty of Sport SciencesUniversity of LeipzigLeipzig 04109Germany

Background:With an increase in the evidence for the associations between park-based physical activity(PA)and physical environments(especially park and neighborhood environments),researchers face an important challenge in interpreting and summarizing the evidence to develop environ?mental change *** updated review is needed to better inform policymaking and environmental *** current study aimed to systematically review the research on the associations of park-based PA with park and neighborhood environmental ***:We targeted English peer-reviewed articles from 5 electronic databases using keywords related to park-based PA,park environments,and neighborhood *** the 4071 identified papers,25 studies published between 2008 and 2016 met all the eligibility criteria and were included in this ***:The characteristics of physical environment that received consistent support included paths/trails,lighting,and incivilities(e.g.,broken glasses and litter).Mixed findings were revealed for 6 park environmental factors(unspecified active facilities,playgrounds and skating areas,fit?ness stations,picnic areas,greenness,and park size)and 2 neighborhood environmental factors(park density and park proximity).Conclusion:It can be concluded that paths/trails,lighting,and incivilities are 3 key physical environmental attributes of park-based *** the inconsistent findings on park and neighborhood environmental factors,more robust designs such as prospective investigation are required.

关键词： Neighborhood Park-based physical activity Park environment Physical environment Systematic review

Size-controllable synthesis of monodispersed nitrogen-doped carbon nanospheres from polydopamine for high-rate supercapacitors

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Frontiers of Chemical Science and Engineering 2023年第11期17卷 1788-1800页

作者： Ning zhang Fu-Cheng Gao Hong Liu Feng-Yun Wang ru-Liang zhang Qing Yu Lei Liu School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China College of Physics and State Key Laboratory of Bio Fibers and Eco Textiles Qingdao UniversityQingdao 266071China

Monodispersed nitrogen-doped carbon nanospheres with tunable particle size(100-230 nm)were synthesized via self-polymerization of biochemical dopamine in the presence of hexamethylenetetramine as a buffer and F127 as a size controlling *** can mildly release NH3,which in turn initiates the polymerization reaction of *** carbon nanospheres obtained exhibited a significant energy storage capability of 265 F·g^(-1)at 0.5 A·g^(-1)and high-rate performance of 82%in 6 mol·L^(-1)KOH(20 A·g^(-1)),which could be attributed to the presence of abundant micromesoporous structure,doped nitrogen functional groups and the small particle ***,the fabricated symmetric supercapacitor device displayed a high stability of 94%after 5000 cycles,revealing the considerable potential of carbon nanospheres as electrode materials for energy storage.

关键词： carbon nanospheres size-controlled nitrogen-doped high-rate supercapacitors