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1.
水泥土桩已普遍用于多层住宅的地基处理,根据水泥土和夯扩挤密施工法的特点,在对夯扩挤密水泥土桩用于高层建筑地基处理进行研究、阐明其经济合理且安全可行的基础上,在高层住宅工程中进行了尝试,已取得令人满意的效果。 相似文献
2.
Rotational Restraint of Pile Caps during Lateral Loading 总被引:1,自引:0,他引:1
A pure fixed-head (zero-rotation) condition at the top of a group of laterally loaded piles is seldom achievable in the field, even when piles are installed in a group that is “rigidly” constrained by a stiff concrete pile cap. Assuming complete fixity during design (zero rotation at the pile head) can result in underestimated values of pile-head deflection, and incorrect estimates of the magnitude and the location of maximum bending moments. A simple and practical approach is presented for estimating the moment restraint that is provided by the pile cap at the top of a pile group. The moment restraint, represented by the rotational restraint coefficient (KMθ), serves as a boundary condition for analyzing groups of laterally loaded piles. Full-scale field tests performed on two pile groups with concrete pile caps show that the proposed method for estimating rotational restraint provides results that are in good agreement with measured field performance. 相似文献
3.
Domenico Ferrari 《Multimedia Systems》1998,6(3):179-185
The research done by the Tenet Group in multimedia networking has reached a point where it may be useful to reflect on the
significance of its results for the current debate on how integrated-services internetworks should be designed. Such reflections
constitute the main subject of this paper. The principles of the work and the conclusions reached so far by the Tenet researchers
are discussed in the light of the conflict between the two major technologies being proposed to build future information infrastructures:
namely, the Internet and the ATM technologies. The Tenet approach suggests one feasible way for resolving the conflict to
the advantage of all the users of those infrastructures. This paper discusses various fundamental aspects of integrated-services
network design: the choice of the service model, the type of charging policy to be adopted, and the selection of a suitable
architecture. 相似文献
4.
随着电动汽车动态无线充电(EV-DWC)技术的发展,针对目前EV-DWC负荷建模理论工作不全面的现状,以交通流量作为影响充电负荷的主要因素,以天气、典型日期、季节等因素为次要影响因素,根据路况建立负荷模型,通过电动汽车型号和状态的聚类不同对汽车分配不同的功率,完成动态充电负荷的建立。采用小波神经网络(WNN)对时序信息进行处理预测,再同误差反向传播神经网络(BPNN)相结合预测充电道路上的车流,短期车流预测精度为85%,用模糊C聚类(FCM)算法对电动汽车的充电类型以及该类型所对应的充电功率进行划分,将进入充电道路的电动汽车分为7种类型。根据各种充电类型分配相应的充电功率,完成日负荷建模。 相似文献
5.
Shalu Kataria Yogendra L. Verma Himani Gupta Shishir K. Singh Nitin Srivastava Ravindra Dhar 《Polymer-Plastics Technology and Engineering》2020,59(9):952-958
ABSTRACTNano-composite polymer gel electrolytes (NPGEs) based on polymer poly(vinylidene fluoride-co-hexafluoropropylene) PVdF-HFP, ionic liquid, 1-butyl-3- methylimidazolium bis(trifluoromethanesulfonyl)imide BMIMTFSI, Li-salt along with the addition of SiO2 nanoparticles have been synthesized and characterized by various techniques. Prepared NPGEs show high room temperature ionic conductivity (~10?3 S/cm) and have a wide electrochemical window (ECW) (~3.3–3.5 V). The galvanostatic charge/discharge profile was studied by sandwiching best performing NPGEs between a LiFePO4 cathode and lithium metal anode. The specific discharge capacity of the cell (Li/NPGE/LiFePO4) room temperature at 0.1C rate is found to be 138 mAh/g. 相似文献
6.
在风光互补发电系统中,蓄电池作为风光互补发电系统的储能设备,在整个发电系统中起着非常重要的作用,而蓄电池充电控制方法的优劣,是影响其使用寿命的一个重要因素。文章对风光互补发电系统中蓄电池的常用充电控制方法进行了分析,提出了一种新的控制策略,即将蓄电池充电电压、充电电流采样值分别与蓄电池事先设定好的恒压过充电压、恒流充电限流值和浮充电流值进行实时比较,来判断采取哪种合理的充电方式,对蓄电池起到尽可能的保护,从而延长了风光互补发电系统中蓄电池使用寿命。 相似文献
7.
Jorge Garcia-Cañadas Jon Kapla Germà Garcia-Belmonte Marten O.M. Edwards 《Electrochimica acta》2004,49(5):745-752
The dynamic response of viologen-activated nanostructured titanium dioxide has been studied by means of electrical and electro-optical measurements. We show that the state of charge of the semiconductor network is the key factor mediating between the electrode potential and colouration of viologen. Theoretically, we relate the electrode potential to the statistics of occupancy of both TiO2 nanoparticles and oxidized viologen molecules attached to the surface, on the assumption of quasi-equilibrium of Fermi levels in these contacting phases. Experimentally, we determine the statistical function from steady-state measurements (electrochemical impedance spectroscopy) of the capacitance of the semiconductor film. From this understanding we explain the main features that correlate the simultaneous voltammetry and transmittance responses. Finally, the redox process of viologen is resolved separately from the TiO2 response by means of transmittance data. 相似文献
8.
随着国家大力发展新能源汽车的政策,电动汽车和充电基础设施规模不断扩大,如何科学地规划充电网点成为亟待解决的问题。本文根据分期规划的原则,采用基于注意力机制的长短期记忆网络进行充电需求预测,使用量子粒子群优化算法进行近期充电网点选址定容,然后根据Voronoi图来划分远期充电站服务区域,从而建立了充电网点精准规划模型。通过对杭州市钱江世纪城区域进行验证,表明本文模型在科学规划充电网点的同时,能够实现电网、企业、用户的多方共赢。 相似文献
9.
Using a one-dimensional self-consistent fluid model, the effect of pulse rise time on charging effects at dielectric surfaces is investigated during plasma immersion ion implantation (PIII) with planar and cylindrical geometries. The numerical results demonstrate that the pulse rise time plays an important role in PIII process with dielectric substrates. It is found that the charge dose accumulated on the dielectric surface is significant as decreasing pulse rise time, and the surface potential decreases at the later stage of the pulse, which results in the lower ion impact energy. On the other hand, the longer pulse rise time would lead to the lower charge dose accumulated on the dielectric surface and higher ion impact energy at the later stage of the pulse, which would elevate the effective implanted dose and introduce the ions to the depth deep enough for surface modification. 相似文献
10.
江西省宜春市宜阳新区位于可溶岩区,岩溶作用形成的溶洞、土洞对地基的稳定性存在重要影响.根据对宜春某建筑场地桩基础超前钻获得溶洞、溶蚀带和断裂构造的位置,分析其空间分布规律,对桩基础结构设计及施工具有关键指导作用. 相似文献