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1.
1.Woulk you like a cup of tea? 要用茶吗?2.Yes,prlease.How much? 好的。多少钱?3.Two yuan each. 每杯2元。4.Here you are. 给。5.Would you like some drinks?Here we have tea,coke,orange squash and mineral water. Which would you like?  相似文献   

2.
1.Can I help you,madam? 女士,要我帮忙吗?2.Yes,I'm looking for the gift shop. 是的。我要找礼品商店。3.It's on the second floor.Please take the escalator over there.  相似文献   

3.
《铁道知识》2003,(2):24-24
1. What can I do for you, madam?女士,要看点儿什么吗?2. I'd like to see that bracelet and thoserings.我想看看这手镯和那些戒指。3. Yes, here you are. They make attractivesouvenirs and lovely gifts that'll constantlyremind people of your China tour.好的。这些都是招人喜爱的纪念品和礼品,而且能经常使人们想起您的中国之游。4. Yes, I think so. I'll take this bracelet and  相似文献   

4.
ABSTRACTS     
Taking the logistic project of Bama mineral water inter-regional transportation by Liuzhou freigh transport center of Nanning Railway Administration, this paper analyzes the process of working out Iogisti planning program from aspects of logistic program, economic analysis and advantages & disadvantage,, analysis. During the practice of railway freight transportation transferring to modern logistics, the thoughts or many aspects were put forward, including: railway enterprise should actively take door-to-door marketing anc expand service scope, should provide extended service chains of logistic value-added actions and organiz~ trans-administration logistic transportation as to increase service quality, all of these have reference meanin( for other scattered "white goods" transportation.  相似文献   

5.
What should we pay attention to in the management of severe spinal deformity? Huafeng Wang, Zhaomin Zheng, Hui Liu. Department of Spine Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510080, China 【Abstract】Severe spinal deformity is not an uncommon condition that often arises from untreated early onset scoliosis in developing countries. Patients most often present with severe clinical and radiographic deformity with poor pulmonary function. Previous literature has identified the challenges in the treatment of these patients and the higher risk for complications. An assessment of the preoperative, intraoperative, and postoperative factors leading to an optimal result was warranted. The early evaluation should include a multidisciplinary approach from the orthopaedic surgeon, pulmonologist, anesthesiologist, and perhaps the neurologist to provide a baseline assessment. Advanced imaging of the spine is useful and important. Current surgical strategies include aggressive anterior and posterior column release and osteotomies, either with a front–back or a posterior-only approach. With the extent of the surgical release and segmental instrumentation, the potential for curve correction is increased; however, so is the potential for neurologic compromise. Therefore, perioperative Halo traction was recommended. It was thought to improve both spinal deformity and pulmonary function and is a helpful adjuvant in the treatment of severe spinal deformity. Improvements in the clinical and radiographic appearance, pulmonary function, and self-image are often dramatic. Proper planning and execution of the correct surgical procedure for the surgeon provides an outstanding life-changing result in these patients.  相似文献   

6.
英国INSPEC数据库,全名为《物理学、电技术、计算机及控制信息数据库》(Information Service for the Physics,Electro-technology,Computerand Control简称INSPEC),是目前全球在物理和工程领域中最全面的二次文献数据库之一,它的前身是“科学文摘”(Science Abstract or SA,始于1898年),被誉为国际六大检索期刊。  相似文献   

7.
Research purposes: Lightning has been one of the important factors endangering safe and reliable operation of the railway. The grounding grid performance plays a particularly important role in lightning protection. In this paper, the author has established a grounding grid transient model by the electromagnetic transient analysis software and intended for quantitative analysis of typically grounding grid layout in engineering practice, to lay important theoretical basis for future lightning protection and grounding. Research conclusions: (1) The results show that the ground potential is significantly affected by the soil resistivity, lightning current amplitude and the mesh size. With increase of the soil resistivity and lightning current amplitude, the ground potential at the point of the lightning current injection will significantly improve, but due to the spark discharge of the soil. The ground potential does not increase exponentially with potential lightning current amplitude. The smaller the mesh size, the better the ground potential attenuation. For example of the lightning current 20 kA and the soil resistivity 100 Ω·m, the ground potential of the 5 m×5 m mesh decreases 22.3% compared with the 10 m×10 m mesh. (2) The study finds that the ground potential attenuation away from the lightning strike point at 15 m basically reaches the maximum, which is about 89%. And the degree of attenuation is independent of lightning current amplitude. (3) The results are mainly used for optimization program and design fields on substation lightning protection and grounding.  相似文献   

8.
Research purposes: The vertical deformation of high-speed railway (HSR) bridge will cause the track irregularity, which threatens the safe and efficient operation of the HSR. Taking the 32 m simple supported beam bridge as the research object, based on the existing mapping analytical model for bridge vertical deformation and rail geometry, the influence of the track regularity of the CRTS Ⅰ slab ballastless track structure caused by the key parameters such as the bridge vertical deformation amplitude, the hanging length of the beam end and the vertical stiffness of mortar layer were studied, and the corresponding measures to control the rail deformation were proposed, to provide theoretical reference for comprehensive treatment of rail deformation of HSR bridge. Research conclusions:(1) The pier settlement, the vertical rotation of the beam end and the beam fault will cause the rail to follow the beam deformation, and "up-warping" of the rail on the vertical deformation boundary will appear. (2) The rail deformation is directly proportional to the vertical deformation amplitude of the bridge and the key to control the rail deformation is to reduce the vertical deformation of the bridge. (3) The rail deformation can be controlled by reducing the hanging length of beam and vertical stiffness of mortar layer. (4) The research results can provide a theoretical reference for controlling the vertical rail deformation of high-speed railway bridges. © 2018, Editorial Department of Journal of Railway Engineering Society. All right reserved.  相似文献   

9.
School, National University of Defense Technology,Changsha 410073,CHN;2. Department of Physics,Dalian University of Technology,Dalian 116023,CHN)ZnO thin films were fabricated on the P-Si,high resistivity Si,ceramic and N-Si substrates by thermal oxidation in air.The oxidation time was fixed to 1h at 300℃~800℃.The effects of different substrates such as the P-Si(111),the high resistivity Si,the ceramics substrates and the N-Si are investigated.To obtain high-quality ZnO films,some Zn films are also annealed in the oxygen.It is found that the ZnO films prepared on the high resistivity Si substrates exhibit the better excitonic ultraviolet (UV) emission,the ceramics substrates exhibit the better deep level visible emission.The ZnO fil  相似文献   

10.
Research purposes: Precise prediction for mechanical behavior of the bridge under ship collision force is important to assess the analysis of train derailment after hitting the pier. This paper focuses on the Tongling Yangtze River Bridge Combined Road with Railway for ship collision simulation, uses the nonlinear finite element software of ANSYS/LS-DYNA to simulate the ship's bow section of 10000 t and 5000 t class hitting bridge tower column at front and axle to 20° of side in highest navigable water level, conventional navigable water level and the minimum navigable water level. Curves of collision force-period at different working conditions are summarized. On this basis, when the impact load affects as input loads, the displacement and acceleration response can be used by finite element analysis under the collision and study the dynamic response of the bridge caused by a train derailment risk. Research conclusions: (1) The impact force of the bridge is largest when a laden ship is hitting the pier at the highest navigable water level. In the most unfavorable condition, the collision have lardge impact on bridge structure and derailment risk of trains. (2) The transverse acceleration of the girder on the top of 2# pier can reach to 0.922 m/s2, but it does not exceed acceleration excitation limit (1 m/s2) when 3# piers are hitted by the 10000 t ship at the peak load of collision, so the probability of train derailment is minimal. (3) Based on the probability formula of the derailment by simplifying risk criteria, the derailment probability of train is 9×10-5~1.5×10-4 during the ship-bridge collision. (4) The research results can provide the reference for train traffic safety on railway bridge caused by ship collisions.  相似文献   

11.
ABSTRACTS     
《现代城市轨道交通》2009,(2):I0001-I0001
Applying the Scientific Outlook on Development to Promote the Construction of Urban Rail Transit
-C Thinking on Current Construction Development of China Urban Rail Transit Jiao Tongshan 1
The construction of China Urban Rail Transit is now staying in the important time with rapid development. The achievements we obtained are objectively summarized. At the same time, the contradiction between the current construction speed and preliminary work, the construction procedure, the phenomena of despising operation, the unified planning of traffic integration, the control of construction standards, the difference of fare in domestic urban rail transit, as well as the enhancement of government management for urban rail transit are analyzed and investigated through some phenomena in the industry. Several suggestions are also presented.  相似文献   

12.
Research purposes: In order to get the time-varying rules of temperature field distribution in the track structure with superelevation and build the horizontal and vertical temperature gradient of ballastless track, a continuous observation of CRTS II; by using temperature sensors on curve segment of a passenger dedicated line was held. Research conclusions: (1) The temperature change of ballastless track between daytime and nighttime is big, the temperature changing value of surface was 24.7℃ in maximum, 19℃ in average. (2) The temperature changing value became small and the time of maximum temperature come late with the increase of distance to surface. (3) At the bottom of the track structure, the temperature changing value was 6.1℃ in maximum, 5.0℃ in average. (4) Fitting curve of vertical temperature gradient of longitudinally connected ballastless track on curve line can be exponential curve, and the curve sharp can match the distribution about the vertical temperature gradient of the code for design of bridge and culvert in China. (5) The horizontal temperature gradient of the CRTS II; longitudinally connected ballastless track included the track slab and support layer, temperature gradient of track slab could be fitted by using quadratic function, temperature gradient of support layer could be fitted by using piecewise linear function. (6) This study can provide guidance for the temperature load model in the design of high speed railway in central China.  相似文献   

13.
英国INSPEC数据库,全名为《物理学、电技术、计算机及控制信息数据库》(Information Service for the Physics,Electro-technology,Computer and Control简称INSPEC),是目前全球在物理和工程领域中最全面的二次文献数据库之一,它的前身是“科学文摘”(Science Abstract or SA,始于1898年),被誉为国际六大检索期刊。它提供涵盖:理论及应用物理,电气和电子工程,  相似文献   

14.
day. Base on the new field works in Shuanghu and Tuotuohe regions of central Tibet by us and the datum have been obtained by other researches on the grabens. We proposed that, the graben structures are distributed in the most part of plateau; including Himalayan, Gangdese and Qian  相似文献   

15.
Research purposes: Transparent sand is a new type of geotechnical engineering material, which is made of fused silica sand and porous liquid with the same refractive index. In order to understand its mechanical properties, the CU and CD tests of fused silica sand with a particle size of 0.5~1.0 mm and 1.0~3.0 mm are carried out by triaxial apparatus, and the stress-strain curves, pore water pressure changes and effective stress ratio of the two are compared and analyzed. In addition, E-μ model parameters of coarse and fine sand are calculated respectively, which provide corresponding parameters for further numerical calculations. Research conclusions:(1) The loose sample's stress-strain curve shows hardening characteristics. (2) The coarse particle specimen with steeper stress-strain curve comes to the peak at faster velocity than fine particle specimen. (3)The pore pressure value of the coarse particle specimen is greater than the fine particle, the pore water pressure coefficient of the two shows a decreasing trend with the increase of the confining pressure. (4) Transparent sand can be used to simulate natural sand and the change of diameter can represent different soils. (5) The research results can provide reference for model tests based on transparent soil technique. © 2018, Editorial Department of Journal of Railway Engineering Society. All right reserved.  相似文献   

16.
ABSTRACTS     
《铁道货运》2009,(4):I0001-I0001
Based on SWOT model, targeting the characteristics of Lanzhou area and combining with the trend of development of logistics enterprises and the characteristics of dangerous goods logistics, this paper analyzes the main factors influencing the layout of dangerous goods logistics center, and puts forward the strategies on layout of the logistics center.  相似文献   

17.
In this paper,IGBT history is briefl y reviewed and IGBT chip technology is discussed in detail,especially for soft punch through,carrier injection enhancement and trench technologies.Concurrently with the improvements in chip technology,there has been rapid development of the packaging technology which will be discussed in this paper.Some suggested technologies of IGBT in the future are presented to conclude the paper.  相似文献   

18.
ABSTRACTS     
《铁道货运》2014,(11):J0001-J0001
Research and Development of Railway Logistic Comprehensive Management System
Following the constant transfer of railway freight stations into railway logistic centers, the business of railway freight transportation has profound change, so the current top priority is developing and establishing the logistic comprehensive management system adapting for railway transport modernization and market demand. The railway logistic comprehensive management system was researched and the business process of the system was optimized from the aspects of characteristic analysis, general idea and key technologies of railway logistic system; the system was developed and established by using BPM workflow engine and development platform as well as Application Integration Platform (ALP), and the main functions of the system was expounded in this paper.  相似文献   

19.
On the basis of the theory of vehicle-track coupling dy-namics and noise radiation and propagation,a model ofwheel/rail noise prediction for the rail transit is founded andthe software for wheel/rail noise prediction is developed.Inthe model,the wheel is …  相似文献   

20.
ABSTRACTS     
《现代城市轨道交通》2009,(3):I0001-I0001
Security Technology of Japan Shinkansen Railway Yu Zhanyou 1
The operation record with zero mortality of Japan Shinkansen for 45 years is based on their management idea of "safety first", strong disaster prevention awareness, advanced and mature technology but not pursuing the most advanced guiding ideology, a set of legal procedures, the severe technology certification system, the accurate traffic control system, the strict overhaul system, as well as the examination and maintenance system. In this paper, the successful experiences of Japan Railway are introduced and summarized, which have important references for safety guarantee of China urban rail transit industry.  相似文献   

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