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81.
This "rutter for piracy" begins with a brief update on contemporary piratical incidents and a short review of books and collections
of articles dedicated to the topic of piracy, before presenting the ground-breaking group of scholarly essays which make up
WMU Journal of Maritime Affairs' special issue on piracy at sea. 相似文献
82.
Z.-G. Zhao L.-J. Zhou J.-T. Zhang Q. Zhu 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(5):750-773
Considering the controllability and observability of the braking torques of the hub motor, Integrated Starter Generator (ISG), and hydraulic brake for four-wheel drive (4WD) hybrid electric cars, a distributed and self-adaptive vehicle speed estimation algorithm for different braking situations has been proposed by fully utilising the Electronic Stability Program (ESP) sensor signals and multiple powersource signals. Firstly, the simulation platform of a 4WD hybrid electric car was established, which integrates an electronic-hydraulic composited braking system model and its control strategy, a nonlinear seven degrees-of-freedom vehicle dynamics model, and the Burckhardt tyre model. Secondly, combining the braking torque signals with the ESP signals, self-adaptive unscented Kalman sub-filter and main-filter adaptable to the observation noise were, respectively, designed. Thirdly, the fusion rules for the sub-filters and master filter were proposed herein, and the estimation results were compared with the simulated value of a real vehicle speed. Finally, based on the hardware in-the-loop platform and by picking up the regenerative motor torque signals and wheel cylinder pressure signals, the proposed speed estimation algorithm was tested under the case of moderate braking on the highly adhesive road, and the case of Antilock Braking System (ABS) action on the slippery road, as well as the case of ABS action on the icy road. Test results show that the presented vehicle speed estimation algorithm has not only a high precision but also a strong adaptability in the composite braking case. 相似文献
83.
目的①观察液压性脑损伤后不同时期室下区Nestin和GFAP的表达及其细胞类型。②分离脑损伤室下区Nestin /GFAP 共存细胞进行培养、诱导分化鉴定。方法①用液压冲击法建立SD大鼠动物模型,用免疫组化和免疫荧光双标法分析和显示不同时期(1、3、5 d,1、2、3、4、6、8周)Nestin和GFAP的表达变化以及细胞类型。②分离液压损伤SD大鼠室下区Nestin /GFAP 共存细胞,制成单细胞悬液,进行培养、传代,以免疫荧光化学方法对原代和传代培养形成的神经球以及诱导分化的细胞进行鉴定。结果①室下区免疫荧光染色:正常组及空白对照组在前脑侧脑室SVZ区出现神经干细胞,主要集中在外侧壁上部和上角,其他部位及三脑室的SVZ区有少量神经干细胞。脑损伤模型组脑损伤24 h后,和正常组相比,室下区Nestin和GFAP的表达显著增加,阳性表达在3 d后逐渐达到高峰,持续1周。②在上述条件下培养及传代的细胞不断分裂增殖,形成悬浮生长的呈Nestin阳性的神经球;神经球贴壁后分化的细胞表现为少突胶质细胞、神经元和星形胶质细胞的形态,且分别呈GalC阳性、β-tublinⅢ阳性和GFAP阳性。结论①成年大鼠液压性脑损伤可诱导室下区表达Nestin和GFAP,Nestin的表达和反应性星形胶质细胞增生呈正相关,且表达多相互共存,并且具有星形胶质细胞的形态;室下区的星形胶质细胞和神经干细胞都对脑损伤都有反应,并可能参与中枢神经系统损伤修复。②成年大鼠液压性脑损伤后分离的室下区细胞具有自我更新能力和多分化潜能,可以分化为神经元、少突胶质细胞和星形胶质细胞,是中枢神经系统的干细胞。 相似文献
84.
广州丰田引进的雅力士(Yaris)是丰田成功进军欧洲市场的一款全球战略车型。目前的这一代雅力士在2005年就已经在欧洲市场推出,是Yaris车系的第二代车型。雅力士的历史可以追溯到上个世纪的1999年,当时丰田在欧洲推出了第一代该款车型。实用的操作设计加上小巧可人的外观,很快就得到了许多消费者的青睐,截至2005年第—代Yaris停产,丰田在全球已经总计生产了超过140万辆的Yaris。到2005年底,欧洲和北美市场首先迎来了第二代Yaris,更加活力清爽的造型设计相比上一代有了明显改观,而个性十足的内饰也突破了丰田汽车的一贯中庸风格,令人耳目一新。第二代Yaris在欧洲上市之后不久,便接受了欧洲E—NCAP的碰撞试验,结果正面碰撞得到了15分(满分16分),侧面碰撞16分(满分18分),最终获得了成人乘员保护5星、儿童成员保护3星、行人保护2星的优异成绩。雅力士在安全性方面早已是家喻户晓的明星。 相似文献
85.
The operation safety of the public transport is seriously threaten by the occurrence of defects and damages in existing urban tunnels, which affects the quality of traffic, and will shorten the service life of urban tunnels. Therefore, it is of great significance to evaluate the damages of the tunnel lining structure quickly and accurately. The damage evaluation methods of the existing urban tunnel lining structure are investigated and analyzed in this paper, and a combination method of the macroscopic evaluation of the existing damaged urban tunnel and the damage mechanism of the lining structural material is proposed. Among them, the assessment method specified in the national criterion is selected to evaluate the damages of the lining structure for the macroscopic evaluation, and the classification of tunnel health levels is optimized. Meanwhile, the damage modulus based on the elastic modulus is selected, and the concept of elastic modulus reduction rate is introduced for the mechanism of damage. Furthermore, the assumed function relationship between the health level and the damage degree of existing urban tunnels is proposed and established, which provides a new idea for structural damage assessment of existing urban tunnels. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved. 相似文献
86.
Sun L.Huang Y.Wang Q.Zhou H.Dai C. 《现代隧道技术》2018,(5):140-145
Based on the background of the first phase project of the R3 line of Jinan Rail Transit, and in view of the metro shield tunnel passing under the existing railway bridge and subgrade, this paper uses Abaqus to establish a numerical model to simulate the deformation of the existing bridge and subgrade of the Jiaoji railway line under the two conditions of non-active reinforcement and reinforcement. The results show that under the condition of no reinforcement, the maximum settlement of the top bridge on the pier is -5.88 mm, and the maximum settlement difference is 5.16 mm, which exceed the deformation control requirements of the 5 mm regarding the bridge pier of the railway with ballast track. The maximum lateral displacement and longitudinal displacement of the pier are 0.28 mm and -3.01 mm, respectively. After the reinforcement measures of the bored piles are adopted, the maximum settlement of the top bridge on the pier is -1.71 mm, and the maximum settlement difference is 1.16 mm, which fully meet the bridge pier deformation control standard. The maximum lateral displacement and longitudinal maximum displacement are -0.245 mm and -2.83 mm, respectively, which meet the requirements of the control standard. The vertical settlement of the railway subgrade is relatively small. The maximum settlement values under the two working conditions are -12.31 mm and -11.97 mm, respectively, which meet the subgrade settlement control requirement of 20 mm. It is proved that the reinforcement effect of the bored pile is good, and the reinforcement scheme is safe and feasible. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved. 相似文献
87.
Law and Characteristics Analysis of Domestic Tunnel Construction Accidents from 2006 to 2016北大核心CSCD
With the rapid development of tunnel construction in China, strengthening statistical studies of domestic tunnel construction accidents is of great significance in order to understand the safety status of tunnel construction and the development trends of tunnel construction accidents and for exploring the direction of future scientific re-search. There were 89 tunnel construction accidents in China (not including subway tunnels or municipal tunnels)from 2006 to 2016. The characteristics of these accidents are analyzed in terms of time distribution, spatial distribu-tion, grade and type of accident according to the statistics by means of line charts, bar charts and pie charts. Corre-sponding prevention and control recommendations are put forward considering the factors such as year, month, work-ing day, time period, region, location, grade and type. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved. 相似文献
88.
W. H. Wang Q. Cao K. Ikeuchi H. Bubb 《International Journal of Automotive Technology》2010,11(6):873-881
Owing to significantly individual differences in everyday driving behavior, it is quite difficult to assess the relative importance
of driver errors compared with vehicle faults or road environment anomalies. This paper briefly presents several basic concepts
for analysis of driving dependability including driving errors, driving reliability, driver recovery from erroneous actions,
and key factors that shape driving behavior. This presentation is followed by construction of a shaping architecture for driving
behavior that consists of a perception stage, a decision-making stage, an execution stage and correlativity among stages,
in addition to internal feedback from complex traffic states. The causation classification of driving errors is then discussed
in the context of three elemental types: perception error, decision-making error and execution error. The emphasis of this
paper is on how to quantify driving dependability in order to identify various erroneous driver actions during traffic accidents.
Specifically, this paper proposes a methodology to measure the probability of driving errors by considering the driver recovery
from erroneous actions. The purpose of model-based driving dependability analysis is to quantitatively and qualitatively analyze
the relationship between driving errors and traffic accidents causations. 相似文献
89.
一说起比亚迪,人们最容易想到的自然是F3。中国汽车工业协会的统计告诉我们,在2009年1~2月自主品牌轿车销量排名中,比亚迪F3仅次于奇瑞QQ排名第二,强大的市场占有份额让人们对比亚迪F3耳熟能详。然而对于后出道的比亚迪F6,虽然市场销量不及前辈F3那般光彩照人,但在C—NCA碰撞试验场上,它的表现却远远胜过了F3。 相似文献
90.
Li J.Jiao G.Deng H.Cao C.Li F.Ma Q. 《中国舰船研究》2022,(5):116-124
Air regeneration, harmful gas purification and atmospheric composition monitoring are the key technologies of submarine atmospheric environment control systems. After years of development, China has made great progress in such systems, which have developed from ensuring the safety requirements of submariner and equipment operation to ensuring the health of submariner and reliability of system for long-term underwater operation. This paper reviews the development history of submarine atmospheric environment control technologies and introduces their future development prospects. The developers of integrated atmospheric environment control technology should learn from foreign submarine and aerosphere equipment technologies, which aim to support long-term submerged operation and comfort demands, and better adapt to future submarine technology development and evolving mission, in order to constantly enhance the level of submarine cabin air quality of the Chinese navy. © 2022 Journal of Clinical Hepatology. All rights reserved. 相似文献