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91.
利用宋桥井田奥灰群孔抽水试验资料,根据补(隔)水边界水位曲线的特征,采用半对数直线图解法,将井田F2-9断层定性为补给边界。为了解补给边界的补给量,选用边界补给量计算方法.计算出了边界补给量占孔流量的65%,从而较客观地确定了井田水文地质条件类型。 相似文献
92.
网络测试中新方法的探讨 总被引:1,自引:0,他引:1
吞吐量是网络测试非常重要的测试指标。文中探讨吞吐量测试的1个新方法,该方法仅用2个端口便可实现对被测设备大量端口的吞吐量测试。此法不仅可以用于2层网络流量的测试,还可以用于3层IP网的测试,具有很好的现实意义。在第3层测试中需要通过VPN来实现IP包转发,测试可以实现跨接口卡的流量测试;应用证明,该方法不仅能测试吞吐量,而且能更好地实现多项综合测试,得到更真实可靠的数据。同时,该方法可以大量节约测试成本,具备多种优点,是1种值得在高校推广的测试方法。 相似文献
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94.
For the study on the ice-induced vibration of a compliant mono-cone structure,a series of model tests were performed from 2004 to 2006.In these tests,the ice sheet before the compliant conical structure was found to be failed in two-time breaking.Based on this important finding,model tests study of the ice force on a compliant multi-cone structure were performed from 2006 to 2007.in these tests,the ice sheet broke before each single cone non-simultaneously.The exciting energy of the total ice force was found to be in a wide range of frequencies,and the structure can be easily excited with nonlinear resonance. 相似文献
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96.
Shu-Guang Song Shu-Cai Li Li-Ping Li Qian-Qing Zhang Kai Wang Yi Zhou 《Marine Georesources & Geotechnology》2016,34(4):376-383
During tunnel excavation, the deformation of surrounding rock due to the unloading of rock mass will vary with time. However, the measured displacement of surrounding rock is only a part of the actual longitudinal deformation profile. There is a need to analyze the longitudinal deformation profile to identify the deformation state and evaluate the stability of surrounding rock mass. In the present article, the variation of pre-deformation of surrounding rock due to excavation was analyzed, and the release coefficient was obtained from the measured results. For the Qingdao subsea tunnel, the measured crown settlement of surrounding rock was analyzed using the regression analysis method, and the longitudinal deformation profile of rock mass was simulated using the numerical calculation method. Moreover, based on the conditions of the subsea tunnel, a solid-fluid coupling model test was carried out to check the reliability of the numerical calculation results. The results of the model test were consistent with the numerical calculation results. 相似文献
97.
Ship motions after damage are difficult to evaluate since they are affected by complex phenomena regarding fluid and structures interactions. The possibility to better understand how ship behavior in damage is influenced by these phenomena is important for improving ship safety, especially for passenger vessel.In this paper an experimental campaign is carried out on a passenger ferry hull, to show the effects of the water dynamics across damage openings on ship motions. Novel aspects of this research include the study of the effects of the damage position on the ship roll response. The study is carried out for still water and for beam regular waves at zero speed.Results from the experiments carried out underline that the roll behavior of a damaged ship is affected by the position of damage opening and not only by its size. Assuming the same final equilibrium conditions after flooding but characterized by different damage openings it is possible to observe how motions RAOs and roll decay characteristics modify according to the opening locations. 相似文献
98.
During the construction process of Qingdao Jiaozhou Bay Undersea Tunnel, the faults and other unfavorable geological discontinuities were often encountered. To study the water inrush mechanism in the faults, both physical model test and numerical analysis were carried out. The results of crown displacement and hydraulic pressure of the monitoring sections in the physical model and numerical model were analyzed in this paper. It was found that the displacement and hydraulic pressure in the process of tunnel construction are often interacted as both cause and effect, and the lower of hydraulic pressure is often accompanied with the growth of its displacement. The changing of the excavation disturbed zone during the excavation in the undersea tunnel was also studied. The results show that the excavation disturbed zone in fault is larger than that in surrounding rock mass, and the excavation disturbance effects in the filling type fault are both transient and persistent. When the displacement and hydraulic pressure in the undersea tunnel change sharply during excavation, there are relatively slow and continuous change trend of the displacement and hydraulic pressure. For practical purposes, to prevent water inrush in the undersea tunnel, more attentions should also be paid to the undersea tunnel after excavation. 相似文献
99.
自升沉式潜标正式布放使用前应进行大量的测试试验工作。为了能够在岸边或实验室对潜标的各项性能进行验证和调试工作,开发了基于LabVIEW的潜标模拟测试系统。该系统充分利用虚拟仪器的特点,采用模块化编程技术,利用软件模拟潜标在水下的各种运动状态及传感器感应的测量参数变化,或通过对现场测量数据的回放查找分析潜标系统本身存在的缺陷,实现潜标不下水或少下水就可以进行全面测试的目的。实验结果表明,利用模拟测试系统可以进行固定值、极值和连续变化值模拟,能够缩短设备开发周期,优化系统控制方案,对提高产品质量具有非常重要的作用。 相似文献
100.
锦州湾沾污沉积物急性毒性的海洋端足类检验 总被引:12,自引:1,他引:12
1992年9月 ̄1993年1月对锦州湾沾污沉积物的海洋端足类急性毒性效应进行了研究。从锦州湾湾顶到湾口沿西南--东北方向每2km等距离采集27个表层沉积我校 品,应用海洋端足类A mpelisca abdita对这些样品进行了10d直流式急性毒性检验,检验指标为死亡率。结果表明,五里河河口处受试生物死亡率最高,为100%,从湾顶该河口处沿东北方向随着距离增加,死亡率逐渐递减,笔架山处最低,仅为2. 相似文献