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681.
This paper presents a simplified numerical model capable of analysing the interaction between the structural dynamic response of elastic-plastic struck plate wall of a fluid tank subjected to wedge impact and the resulting fluid motion. The Variational Finite Difference Method (VFDM) is applied to analyse the structural dynamics of the struck plate and 2-D linear potential flow theory is used to study the resulting fluid motion and its effects on the structural dynamics of the struck plate. Experiments of a wedge indenter impacting with both empty and 90% filled tanks are carried out to study the structural deformation of the struck plate. The accuracy of the developed numerical model is validated with published results and experimental results, and good agreement is achieved. Through the comparison of the impact behaviour of empty and partially filled water tank, it is found that the resulting water motion helps to reduce the structural deformation of the struck plate since part of the impact energy is dissipated by the resulting water motion. Parametric studies are performed to investigate the effect of impact velocity and water level on the structural dynamics of the struck plate of a partially filled water tank. A case study is also conducted to demonstrate the potential application of the proposed method in analysing ship-ice impact problems.  相似文献   
682.
ABSTRACT

The logistics environment between China and Korea has been changing rapidly in line with the ‘Go West’ policy of international trade and logistics area. The policy includes the BRI, Western Development Strategy, and Korea–China FTA. Against this background, the Korea–China train ferry (KCTF) is being newly illuminated as an alternative mode to cope with the logistics environment between Korea and China. One of the key success factors of the KCTF depends on, among others, shippers’ perception, which will affect the choice and the successful operation of the KCTF. From this perspective, this paper develops seven hypotheses based on the Theory of Reasoned Action (TRA) and Technology Acceptance Model (TAM). We test these hypotheses using Structural Equation Modeling (SEM) to explore the structural relationship between shippers’ behavioral beliefs influencing the perceived usefulness, the attitude toward and intention to choose the KCTF. The test results confirm that among the behavioral beliefs, transport accessibility in association with an efficient network of inland roads and railway networks is an important prerequisite. In addition, we verified a high statistical significance in the structural relationships among perceived usefulness, the attitude toward and the intention to choose the KCTF.  相似文献   
683.
VPP can be used to deter mine the maxi mumvelocities of a sailboard at various sailing-routes,byestablishing the forces and moments balance-equa-tions on the sail and board in accordance with theprinciple of the maxi mal drive-force.Selectingroute is the most i mportant issue in upwind-sailing,and VPP calculations could provide the basis for de-ter mining the opti mal routes.VPP calculation of the sailboard perfor mance isa complex and difficult research task,and there arefew projects in thi…  相似文献   
684.
通过对桥头跳车现象的产生机理及其危害的分析,结合实际工作经验,提出防治措施,并对此防治措施展开探讨。  相似文献   
685.
As the traditional RISC ASIC/ASSP approach for network processor design can not meet the today‘s requirements, this paper described an alternate approach, Reconfigurable Processing Architecture, to boost the performance to ASIC level while reserve the programmability of the traditional RISC based system. This paper covers both the hardware architecture and the software development environment architecture.  相似文献   
686.
Code divisionmultipleaccess (CDMA )isaspread spectrummultipleaccessschemethatisex pectedtogainasignificantshareofthecellularmar ket.CDMAhasseveralattractivepropertiesforper sonalcommunications.Andifallmobileradiosig nalsarrivingatthebasestationaresynchronizedtowithinafraction ,thesynchronousCDMA (S CD MA)systemscanenhancethebandwidthefficiencytoa greaterdegreebyemployingorthogonalcodewords.However,S CDMAsystemshavefunda mentaldifficultieswhenutilizedinafrequency se lectivefadingenviron…  相似文献   
687.
本文对8一节点四边形轴对称杂交/混合元AXHM16进行了系列考核:(1)考查AXHM16是否含有零能变形模式,以查明它的含秩状况;(2)通过受内压作用的厚壁球壳考题,观察AXHM16的转轴不变性和其它性能表现。事实表明:AXHM16满足单元合理足秩的必要条件和充分条件,不含零能变形模式,单刚合足秩。数值考核表明:AXHM16具有很好的位移精度和应力精度,对坐标转轴的敏感程度并不明显,且在近乎相同的  相似文献   
688.
应用3H-TdR及14C-UR参入淋巴细胞的双标记方法,在体外培养条件下,研究多抗甲素对人淋巴细胞DNA及RNA合成功能的影响。结果表明,在多抗甲素的浓度为0.1~10mg/L时,可显著增强淋巴细胞DNA及RNA的合成功能;当多抗甲素的浓度增至50~100mg/L时,对淋巴细胞合成DNA及RNA的能力呈现抑制作用,3H及14C标记物的参入计数减少。多抗甲素对淋巴细胞DNA及RNA合成功能的影响呈现双相作用。  相似文献   
689.
采用经颈部向颅内插入及再拔出尼龙线的方法复制了鼠基底节梗塞,并观察了基底节区的血管密度。结合临床资料发现,外伤后基底节梗塞的发生与基底节区血管的构铸特点、颈总动脉(CCA)或(及)颈内动脉(ICA)的病变以及外伤对其的进一步影响有密切关系。  相似文献   
690.
提出了基于层次分析法的集装箱装卸工艺方案优化评价研究,此方法是将复杂问题分解为若干组成要素,并将这些要素按支配关系形成有序的阶梯层次结构;然后通过两两比较,确定层次中诸要素的相对重要性;最后综合各层次要素的重要程度,得到诸要素的综合评价值.  相似文献   
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