Using of the Tape Extensometer for Possibilities of Landslide Monitoring or another purposes

The main goal of this article is to analyze the possibility of using tape extensometry. It is one of the methods of evaluating the development of slope deformation. Tape extensometry is used to monitor the movement of the slope on the surface. Tape extensometry is used for fast and accurate measurement of relative distances between pairs of reference points on the surface of structures, including radial movements and convergence of tunnels, linings, shafts and caves. Then deformations of excavations in underground caves and displacements of retaining walls, bridge piers and arches. The digital tape extensometer is a portable device used to measure the displacement between pairs of eye bolts. The principle of measuring on a slope consists in directly measuring the distance between the stabilized measuring points. The measuring points are located in both stable and unstable parts. The measuring points are concreted into boreholes drilled to a non-freezing depth, which in the Czech Republic is about 0.8 m below the ground. The direction of movement can be determined by measuring the change in distance between several points located in the stable part and points in the unstable part. If we also measure in time intervals, we can also find out the approximate speed of movement. The tape extensometry method is performed using a tape extensometer. It is a specially adapted zone in which emphasis is placed on the material from which the meter is made, because it is important that the material has a low thermal expansion, for example nickel steel is suitable.

Seismic Site Response of A Large Deep-seated Rock Slope Revealed by Field Monitoring and Geophysical Methods

Shidaguan Slope (hereinafter short for SDG Slope) is an unstable rock slope with an area of 30.78×104 m2 and a deformation depth of 30-70 m in Maoxian County, Sichuan Province, China. Three seismometers (P2-P4) with high sensitivity were installed at different locations on the unstable part of the slope. P2 and P3 were almost at the same elevation (2221 m and 2247 m), while P4 was the lowest (at 2140 m). Another seismometer (P1) sat in a stable location at a higher elevation (2373 m). 99 shallow earthquakes were analyzed. According to the peak acceleration ratios of three seismometers (P2-P4) on the unstable part and another seismometer (P1) on the stable part, the points at lower elevations showed greater seismic amplification (with the amplification coefficient of 2.64-3.51) than one at a higher elevation. And points at relatively thinner part (23 m thick) of unstable slope showed greater seismic amplification than ones at thick part (60-75 m thick). The same rule was also found in studying the site-epicenter azimuth and earthquake magnitude data. Based on the relationship between amplification coefficient and resistivity and rock core, the seismic response amplification was affected by the lithofacies difference. The lithofacies with resistivity values of 50-100 Ohm.m and RQD values of 0-50 % incurred seismic response amplification, which was restrained by the below lithofacies with resistivity values of 10-50 Ohm.m and ROD values of 0 %. When building on slope areas, the lithofacies difference should be taken into full consideration.

Thermal instability revisited

ABSTRACT Field’s linear analysis of thermal instability is repeated using methods related to Whitham’s theory of wave hierarchies, which brings out the physically relevant parameters in a much clearer way than in the original analysis. It is also used for the stability of non-equilibrium states and we show that for gas cooling behind a shock, the usual analysis is only quantitatively valid for shocks that are just able to trigger a transition to the cold phase. A magnetic field can readily be included and we show that this does not change the stability criteria. By considering steady shock solutions, we show that almost all plausible initial conditions lead to a magnetically dominated state on the unstable part of the equilibrium curve. These results are used to analyse numerical calculations of perturbed steady shock solutions and of shocks interacting with a warm cloud.

Stability of barotropic vortex strip on a rotating sphere

We study the stability of a barotropic vortex strip on a rotating sphere, as a simple model of jet streams. The flow is approximated by a piecewise-continuous vorticity distribution by zonal bands of uniform vorticity. The linear stability analysis shows that the vortex strip becomes stable as the strip widens or the rotation speed increases. When the vorticity constants in the upper and the lower regions of the vortex strip have the same positive value, the inner flow region of the vortex strip becomes the most unstable. However, when the upper and the lower vorticity constants in the polar regions have different signs, a complex pattern of instability is found, depending on the wavenumber of perturbations, and interestingly, a boundary far away from the vortex strip can be unstable. We also compute the nonlinear evolution of the vortex strip on the rotating sphere and compare with the linear stability analysis. When the width of the vortex strip is small, we observe a good agreement in the growth rate of perturbation at an early time, and the eigenvector corresponding to the unstable eigenvalue coincides with the most unstable part of the flow. We demonstrate that a large structure of rolling-up vortex cores appears in the vortex strip after a long-time evolution. Furthermore, the geophysical relevance of the model to jet streams of Jupiter, Saturn and Earth is examined.

Fundraising for life: the children's cancer center of Lebanon

Subject area Fundraising, Marketing Strategy. Study level/applicability Undergraduate and Postgraduate. Case overview Professional fundraising plays a key role in the operation and sustainability of various forms of organizations, particularly non-governmental organizations (NGOs). “Fundraising for Life” is the success story of a center that is totally dependent on fundraising to achieve its mission of lifesaving and treatment for children with chronic diseases regardless of their financial situation. This case sheds the light on the primary sources of contributions, the importance of an integrated development program, the mutual benefits of partnering with other entities and the challenges encountered in the fundraising endeavors in this developing and unstable part of the world. Expected learning outcomes The students will be able to explore the current practices used in fundraising as well as the marketing and communication strategies employed in nurturing and maintaining relations with potential donors and partners. They will also be able to explore the internal and external challenges and opportunities available for fundraisers. Supplementary materials Teaching notes are available for educators only. Please contact your library to gain login details or email [email protected] to request teaching notes.

Intelligent Power Swing Detection Scheme to Prevent False Relay Tripping Using S-Transform

Distance relay design is equipped with out-of-step tripping scheme to ensure correct distance relay operation during power swing. The out-of-step condition is a consequence result from unstable power swing. It requires proper detection of power swing to initiate a tripping signal followed by separation of unstable part from the entire power system. The distinguishing process of unstable swing from stable swing poses a challenging task. This paper presents an intelligent approach to detect power swing based on S-Transform signal processing tool. The proposed scheme is based on the use of S-Transform feature of active power at the distance relay measurement point. It is demonstrated that the proposed scheme is able to detect and discriminate the unstable swing from stable swing occurring in the system. To ascertain validity of the proposed scheme, simulations were carried out with the IEEE 39 bus system and its performance has been compared with the wavelet transform–based power swing detection scheme.

Stability Limits of Reversible-Pump Turbines in Turbine Mode of Operation and Measurements of Unstable Characteristics

Measurements have been performed on a reversible-pump turbine model installed in a closed loop conduit system. The characteristics of the unstable pump turbine in turbine mode show a hysteresis pattern. Hence the output of the system is dependent on the previous state of the flow and not only the input variables. The hysteresis pattern is a characteristic of the whole system, but is caused by the unstable pump turbine. The unstable part of the characteristics was measured by three different methods: 1) by transient sampling of data during the transition between operation modes, 2) by throttling valves that steepens the friction-loss curve, and 3) by switching the causality in the system such that the torque becomes an input parameter and the speed of rotation becomes an output parameter. In the valve throttling measurements a pressure dependency was seen for the characteristics at high nondimensional speeds. This was further investigated by additional measurements of the characteristics at three different pressure levels. A rigid-water-column stability analysis has been conducted. The classic H-Q criterion describes static stability for a pump turbine with constant speed of rotation. With the speed of rotation as a variable, there is a new static stability criterion in addition to the dynamic stability criterion.

Eigenvalue enclosures and exclosures for non-self-adjoint problems in hydrodynamics

In this paper we present computer-assisted proofs of a number of results in theoretical fluid dynamics and in quantum mechanics. An algorithm based on interval arithmetic yields provably correct eigenvalue enclosures and exclosures for non-self-adjoint boundary eigenvalue problems, the eigenvalues of which are highly sensitive to perturbations. We apply the algorithm to: the Orr–Sommerfeld equation with Poiseuille profile to prove the existence of an eigenvalue in the classically unstable region for Reynolds numberR=5772.221818; the Orr–Sommerfeld equation with Couette profile to prove upper bounds for the imaginary parts of all eigenvalues for fixedRand wave numberα; the problem of natural oscillations of an incompressible inviscid fluid in the neighbourhood of an elliptical flow to obtain information about the unstable part of the spectrum off the imaginary axis; Squire’s problem from hydrodynamics; and resonances of one-dimensional Schrödinger operators.