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1.
通过对事故致因因素的分析,引入并修正了轨迹交叉论事故触发模型在公交系统中的表现形式,并针对公交系统的资源特点对人因差错、物因缺陷事故运动轨迹的形成进行了深刻的分析.根据对公交系统主要事故致因因素的分析,特别着重于对驾驶员的不安全行为进行研究,阐明驾驶员的不安全行为在事故致因中的复杂性和控制的重要性.通过对反轨迹交叉的事故干扰研究,得出了适合公交系统的反事故措施模式,并结合管理学中冲突的解决原理提出反交叉式干扰事故模式,希望导入安全行为可以降低人因差错、物因缺陷轨迹交叉的概率,进而根据公交系统的运行特点,提出几点有实际意义的控制人因的反事故交又干扰方法,以供实践借鉴.  相似文献   

2.
对交通事故持续时间分析的发展现状进行了综述.首先简要介绍了交通事故的定义,事故种类和交通事故管理系统,并分析了交通事故持续时间的统计分布.然后,对最近应用的几种主要的交通事故持续时间的分析方法及结论进行了概述.主要包括:方差分析,线性回归,非参数回归,决策树法,hazard duration method,模糊逻辑.主要的结论包括;大量的研究发现交通事故持续时间的分布形状是向左偏斜的钟型分布.交通事故数据采集标准化是事故分析中非常重要的环节.传统的统计分析方法处理不完整的数据有局限性.最后,本文提出了将来的发展方向,包括应用人工智能方法建立事故持续时间模型,及建立交通事故数据库标准.  相似文献   

3.
为改进传统的驾驶员差错事故分析方法,探索机动车驾驶员差错事故致因分析的新途径. 本文基于道路交通事故案例与调研数据资料,从微观角度分析机动车驾驶员自身差错事故,建立了驾驶员自身差错交通事故致因模型;运用改进的层次分析法确定了导致驾驶员自身差错事故发生的主要影响因素权重,减少了主观因素对分析精度的影响. 结果表明,在机动车驾驶员自身差错交通事故中,驾驶员感知差错率占50.2%,判断决策差错率占38.9%,操作差错率仅占10.9%. 机动车驾驶员感知和判断能力较差是导致交通事故发生的重要因素. 研究结果可为机动车驾驶员事故预防与控制提供科学依据.  相似文献   

4.
新陈代谢GM(1,1)模型在全社会用电量预测中的应用   总被引:1,自引:0,他引:1  
文中通过对比新陈代谢GM(1,1)模型和一般GM(1,1)模型以及传统的系统理论方法在全社会用电量上的预测结果,表明新陈代谢GM(1,1)模型在处理该类数据上具有一定的优势,并且实用性很强.  相似文献   

5.
论述了公路建设中缓和曲线的1:1:1设计的方法,并进行了公式的推导,可操作性强。  相似文献   

6.
本文首先对近10年来云南省发生的937起一次死亡3人以上的特大道路交通事故的数据进行了分析,寻找特大交通事故发生的时间、地域特点以及与道路、车辆、驾驶人以及经济增长之间的关系;并进一步对今年以来发生的42起特大交通事故从人、车、路、事故形态、事故直接原因等方面进行详细分析,指出特大交通事故在驾驶人的分布特征、肇事车辆特征、公路的具体分布方面的主要特点与规律。在此基础上,从社会经济发展、山区道路的安全性、路面的交通执法管理以及道路交通安全管理的社会化等方面,对特大事故发生的深层次原因进行探讨,由此简要提出预防特大交通事故的基本思路。  相似文献   

7.
比较了SDH传送网采用不同自愈保护机制的性能,介绍了高速公路综合通信系统中所采用的几种方案。与传统方案相比,IBAS(综合宽带接入系统)所采用的两纤单向通道倒换具有更好的优越性。  相似文献   

8.
基于灰色残差GM(1,1)模型的汽车货运量预测   总被引:2,自引:1,他引:1  
针对近年来我国汽车货运量增长迅速的特点,运用灰色系统预测模型GM(1,1)对某地汽车货运量趋势进行预测,通过残差GM(1,1)模型对主模型的修正,并用后验差检验法对模型精度进行分析和检验,得到一个精确度非常高的预测模型,该模型符合汽车货运量的预测,并在实际预测应用中取得较好效果。  相似文献   

9.
Different fromthe biallelic expression mannerof most common autosomal genes,i mprinting is aspecial genomic expression phenomenon,of whichthe i mprinted genes show parental-specific expres-sion only according to their parental origin[1].Cor-rect i mprintingis i mportant inthe nor mal embryon-ic development,postnatal growth,as well as behav-ior of ani mals.Dysregulation of i mprinting hasbeen i mplicated in the pathogenesis of congenitaldiseases and cancer[2-3].To date,78kinds of mousei mprinte…  相似文献   

10.
���ڻ�ɫϵͳ���۵Ĺ�·��Ŀ���Ч������   总被引:1,自引:1,他引:1  
运用系统工程理论方法,针对目前我国公路建设项目后评价工作中所面临的社会经济效益定量评价这一难题,提出当统计数据缺乏的情况下选择、运用灰色预测模型对指标进行定量分析、预测的新思路;以厦门海沧公路大桥项目为背景,结合定性分析,采用灰色系统理论中的缓冲算子公理,建立了GM(1,1)模型和灰色线性回归组合模型对数据进行拟合和预测,取得了满意的结果.  相似文献   

11.
目的观察利多卡因对大鼠脑缺血再灌注损伤后海马组织细胞间黏附分子-1(ICAM-1)及核转录因子-κB(NF-κB)蛋白和mRNA表达的影响,探讨利多卡因脑保护作用的机制。方法雄性SD大鼠32只,随机分为假手术组(A组)、缺血再灌注组(B组)、利多卡因小剂量组(C组)和利多卡因大剂量组(D组),缺血前10 min腹腔注射。脑缺血10 min再灌注24 h时,断头处死大鼠。用RT-PCR技术检测海马组织ICAM-1及NF-κB mRNA的表达,用免疫组织化学、蛋白印记(Western blot)方法检测ICAM-1及NF-κB蛋白表达情况。结果脑缺血再灌注后海马组织ICAM-1和NF-κB mRNA及蛋白表达水平增高,利多卡因可下调ICAM-1及NF-κB表达;缺血再灌注后,海马区神经元出现明显坏死,利多卡因可减轻海马区神经元损伤。结论利多卡因可能通过抑制ICAM-1与NF-κB基因表达而对脑缺血再灌注损伤起到一定的保护作用。  相似文献   

12.
13.
A rapid method for the simultaneous determination of berberine (BBR), matrine (MT) and oxymatrine (OMT) by nonaqueous capillary electrophoresis (NACE) was developed. Optimum separation of the analytes was obtained on a 50cm×50μm i.d. fused-silica capillary using a non-aqueous buffer system of 70mM ammonium acetate, 7.0% acetic acid and 10% acetonitrile at 25kV and 20℃. The relative standard deviations (R.S.D.) of the migration times and peak areas of the three active components were 0.06%-0.20% and 0.12%-3.41% for berberine, 0.11%-0.60% and 0.74%-1.63% for matrine, 0.15% and 0.45% for oxymatrine, respectively. Detection limits of berberine, matrine and oxymtrine were 0.18μg/mL, 4.08μg/mL and 4.16μg/mL, respectively. In the tested concentration range, good linear relationships (0.9992 for berberine, 0.9988 for matrine and 0.9988 for oxymatrine) were observed. The linear calibration ranges were 0.45-360.0μg/mL for berberine, 8.16-408.0μg/mL for matrine and 20.8-416.0μg/mL for oxymatrine. This method has been successfully applied to the phytochemical analysis of alkaloids extracts from two commonly used traditional Chinese herbal drugs: Sophora flavescens Ait. (Kushen) and Cortex phellodendri chinensis (Huangbai) and their medicinal preparations.  相似文献   

14.
Objective To study the therapeutic effects of Ginsenoside Rg-1 and Gastrodine on rats model of Alzheimer's disease(AD). Methods Aggregated β-Amyloid peptide (25-35) was injected into the lateral ventricle of rats to establish AD models. Ginsenoside Rg-1, Gastrodine and Ginsenoside Rg-1+Gastrodine were intraperitoneally injected into rats of each test group(Ginsenoside Rg-1∶10mg/kg·day; Gastrodine 100mg/kg·day) for 4 weeks, the rats of control group received equal volume of saline. Passive avoidance task and Morris maze test were done to assess the ability of learning and memory. The content of superoxide dismutase (SOD), malondiadehyde (MDA), total-antioxidative capability (T-AOC), Choline acetyltransferase (ChAT) and acetylcholinesterase (AchE) in brain tissue were measured. Results Ginsenoside Rg-1 and Gastrodine significantly improved learning and memory deficits in the rats with AD induced by β-Amyloid peptide (25-35) (P<0.05). Ginsenoside Rg-1+Gastrodine group were better than Ginsenoside Rg-1 group and Gastrodine group (P<0.05). Ginsenoside Rg-1 reduced the increase of SOD, MDA, but inhibited the decrease of T-AOC, AchE and ChAT; Gastrodine reduced the increase of SOD, MDA, while inhibited the decrease of T-AOC. Gastrodine could also prevent the activity of ChAT and AchE decline in AD rats. Conclusion Both Ginsenoside Rg-1 and Gastrodine have therapeutic effects on rats with AD; Ginsenoside Rg-1 and Gastrodine injection at the same time were better than only using one of them. Their mechanisms might different. Ginsenoside Rg-1 can not only inhibit peroxidation but also increase the activity of AchE and ChAT in brain tissue, while Gastrodine can inhibit peroxidation only, but it can't prevent the decline of ChAT and AchE activity in AD rats.  相似文献   

15.
Researcheshavealreadydemonstratedthatscav engerreceptorclassA(SR A)isabletobindoxidizedlowdensitylipoprotein(OxLDL)withhighaffinityandisoneofthemainreceptormediatingmurinemacrophagetouptakeOxLDL[1] .Itisalsoexpressedinhumanperipheralbloodmonocyte[2 ] andathero scleroticlesions[3 ] .However ,functionsofSR Ainmediatinghumanperipheralbloodmonocytetoup takeOxLDLaswellaspromotingtheatheroscleroticimmuno pathologicallesioninthelocalbloodvesselarestillunclear .Soforthepurposeofstudyingthefunc…  相似文献   

16.
Objective To examine antisense and decoy oligonucleotides of nuclear factor kappa B in vivo effects on intima proliferation and balloon-injured monocytes chemotactic protein-1 ( MCP-1 ) and extracellular signal regulated kinase-2 ( ERK2 ) expression in the carotid artery of rats. Methods Sprague-Dawley rats underwent balloon-dilation injury of the left carotid artery. Rats are divided into 7 groups ( n = 18 ) and each group includes 6 time points (6 h, 1, 3, 5, 7, 14 d) ( n =3). Uninjured right carotid artery of the same rat was used as controls. Results In model group, sense group and scramble group, vessel intima area , media area and intima/media ratio increased after 5 d and reached the maximum after 7 d. The effect of antisense plus decoy group on intimal hyperplasia was more obvious than that of antisense group and decoy group alone. MCP-1 mRNA expression was increased expression continuously at 3, 5 and 7 d and decreased at 14 d. Compared with model group, sense group and scramble group, antisense group, decoy group and antisense plus decoy group had lowered MCP-1 mRNA expression in each time point ( P < 0. 05 ). NF-κB p65 was dispersed positive stain 6 h after injury and increased after 1 d and peaked at 7 d, but the protein expression was weak at 14 d. ERK2 protein synthesis increased at 1 d and reached the peak at 7 d, while protein expression after 14 d was similar to that at 7 d. Treatment of antisense group,decoy group and antisense plus decoy group inhibited protein synthesis more significantly than those of model group,sense group and scramble group ( P < 0. 05 ). Conclusion NF-κB modulates genes expression and protein synthesis of MCP-1 and ERK2. Celluar proliferation in vessel wall was dynamically changed after balloon angioplasty injury. Antisense and decoy oligonucleotide of NF-κB by local lipofectamine transfer inhibit NF-κB activating gene modulation and neointimal hyperplasia.  相似文献   

17.
Sepsisischaracterizedbyreleaseofexcessiveamountofproinflammatorycytokinesinthecircu lation ,leadingtoa generalizedanduncontrolledhostresponse .Aconsiderablenumberofexperimen talandclinicalinvestigatorshavereportedemploy inghemofiltration (HF)toeliminatecytokinesandchemokines .Thisexcessiveinflammatoryresponsecouldbedownregulatedwithremovalofcytokinesandothermediators .Thesedatashowedthatthemechanismofmediatorseliminationwaslinkedtoconvectionandadsorptionbyhemofiltration .Ad sorptionappearstob…  相似文献   

18.
Photodynamictherapy(PDT),whichinvolves administrationofatumorlocalizing photosensiti zingagentthatmayrequiremetabolizingsynthesis(i.e.,aprodrug),followedbyactivationofthea gentbylightofaspecificwavelength.Thistherapy resultsinasequenceofphotochemicalandph…  相似文献   

19.
Objective To study the inhibitory effects of caspase-3 mRNA antisense oligodeoxynucleotides (ASODN) on expressions of caspase-3 and it's mRNA in γ-radiation induced apoptotic HL-60 cells, and screen the effective ASODN. Methods ASODN-1 and ASODN-2 targeting 5′-noncoding region and initial translation region of caspase-3 mRNA were respectively designed, synthesized and introduced into HL-60 cells by means of liposome-mediated transfection followed by 10Gy γ-radiation exposures. TUNEL assay was conducted to investigate the morphologic change and apoptotic percentage of HL-60 cells 18 h later. Immunocytochemical staining and one step RT-PCR were respectively performed to detect the expressions of caspase-3 and it's mRNA. Mismatched oligodeoxynucleotide (MODN) transfected and un-transfected HL-60 cells were taken as control. Results TUNEL assay found that the apoptotic percentages in ASODN-1 and ASODN-2 groups were significantly reduced compared with the control groups (P<0.01) when the final concentration of both ASODNs was ≥3μmol/L. Immunocytochemistry showed that caspase-3 positive cell percentages were reduced but the average gray values increased significantly compared with the control groups (P<0.01). RT-PCR showed expressions of caspase-3 mRNA was decreased after ASODN transfection. Furthermore, ASODN-1 proved more effective in inhibiting HL-60 cell apoptosis than ASODN-2 (P<0.01). Conclusion Caspase-3 mRNA ASODNs can prevent HL-60 cells from apoptosis induced by γ-radiation and reduce expression of caspase-3 and its mRNA. These effects are dose dependent in a certain range.  相似文献   

20.
目的 探讨Th1和Th2细胞因子表达谱研究在V型疮性肾炎(V-LN)患者中的作用.方法 分离血清,通过抗体芯片技术同时检测4种Th1和5种Th2细胞因子表达谱,并探讨其与临床指标之间的相关性.结果 ①细胞因子表达谱:在同时检测的9种细胞因子中,V-LN患者有4种表达上调,除了IL-2属于Th1细胞因子外,其他三种(IL-4、IL-10和IL-13)均属于Th2细胞因子,其中IL-10较健康对照升高了10倍以上.②相关性研究:Pearson相关分析显示IL-10与SLIEDAI呈正相关、与血红蛋白浓度呈负相关;此外,IL-4和IL-13均与尿蛋白浓度呈负相关,IL-1与血肌苷之间呈正相关.结论 V-LN患者体内细胞因子表达异常以Th2细胞因子为主,提示抗Th2细胞因子可能在V型狼疮患者中具有一定的治疗作用.  相似文献   

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