Stability Analysis of Brahmaputra Riverbank at Neulgaon

River bank erosion is a recurrent problem in Jorhat district of Assam. Most of the rivers in Jorhat are shifting in nature and thus river bank erosion is common. Erosion has lead to the general widening of the river and instability of the river banks. River migration and land degradation displaces large number of people annually. This study intends to investigate the nature of river erosion and provision of adequate structural measures. Hydrological data and topographical sheet gathered from government departments have been used as a basis for this project. Software analysis and chronological survey techniques are used for the measurement of channel migration and thus eroded distances. Based on software viz. ARCGIS, channel migration of the river Brahmaputra in Neulgaon, Jorhat is found out. Secondary data were also collected from the local residents to explain the erosion status. The geotechnical properties of the eroded site are important parameters for construction of anti-erosion structures. The design of a structure mainly depends on the topography, hydrological data, and the materials of construction, the mode of construction, and various dynamic properties of the soil. Engineering tests (Field work & laboratory work) has been performed to find its suitability as construction materials. Embankments are the oldest known forms of flood protection works and have been used extensively for this purpose. It is designed in accordance with BIS code 12094:2000. Stability check is then carried out to determine the safety factors

Anomalous thermal expansion of Sb2_2Te3_3 topological insulator

We have investigated the temperature dependence of the linear thermal expansion along the hexagonal c axis ($\Delta L$), in-plane resistivity ($\rho$), and specific heat ($C_p$) of the topological insulator Sb$_2$Te$_3$ single crystal. $\Delta L$ exhibits a clear anomaly in the temperature region 204-236 K. The coefficient of linear thermal expansion $\alpha$ decreases rapidly above 204 K, passes through a deep minimum at around 225 K and then increases abruptly in the region 225-236 K. $\alpha$ is negative in the interval 221-228 K. The temperature dependence of both $\alpha$ and $C_p$ can be described well by the Debye model from 2 to 290 K, excluding the region around the anomaly in $\alpha$

Ultrasonic Nondestructive Evaluation of Composite Materials using Fractal Graphs

In nondestructive evaluation of composites, ultrasonic C-scan technique is perhaps the most versatile and widely practised. In recent years, automated C-scan has become possible. which incorporates advanced features as digitisation and storage of analog data, in real-time. However, C-scan images are still evaluated by visual inspection. In the present work, Fractal theory is proposed as a viable supplement to this human inspection. A simple fractal algorithm has been implemented for such an exercise

Detection of SUSY Signals in Stau Neutralino Co-annihilation Region at the LHC

We study the prospects of detecting the signal in the stau neutralino co-annihilation region at the LHC using tau leptons. The co-annihilation signal is characterized by the stau and neutralino mass difference (dM) to be 5-15 GeV to be consistent with the WMAP measurement of the cold dark matter relic density as well as all other experimental bounds within the minimal supergravity model. Focusing on tau's from neutralino_2 --> tau stau --> tau tau neutralino_1 decays in gluino and squark production, we consider inclusive MET+jet+3tau production, with two tau's above a high E_T threshold and a third tau above a lower threshold. Two observables, the number of opposite-signed tau pairs minus the number of like-signed tau pairs and the peak position of the di-tau invariant mass distribution, allow for the simultaneous determination of dM and M_gluino. For dM = 9 GeV and M_gluino = 850 GeV with 30 fb^-1 of data, we can measure dM to 15% and M_gluino to 6%.Comment: 4 pages LaTex, 3 figures. To appear in Proceedings of SUSY06, the 14th International Conference on Supersymmetry and the Unification of Fundamental Interactions, UC Irvine, California, 12-17 June 2006. A typo in a reference is correcte

Fixed points of fuzzy mappings in Hilbert spaces

In this paper we work out two fixed point theorems for fuzzy mappings on Hilbert spaces. The proofs rely on the paralellogram law in Hilbert spaces

Incidence of HI 21-cm absorption in strong FeII systems at 0.5<z<1.50.5<z<1.5

We present the results from our search for HI 21-cm absorption in a sample of 16 strong FeII systems ($W_{\rm r}$(MgII $\lambda2796$) $\ge1.0$ \AA\ and $W_{\rm r}$(FeII $\lambda2600$) or $W_{\rm FeII}$ $\ge1$ \AA) at $0.5<z<1.5$ using the Giant Metrewave Radio Telescope and the Green Bank Telescope. We report six new HI 21-cm absorption detections from our sample, which have increased the known number of detections in strong MgII systems at this redshift range by $\sim50$%. Combining our measurements with those in the literature, we find that the detection rate of HI 21-cm absorption increases with $W_{\rm FeII}$, being four times higher in systems with $W_{\rm FeII}$ $\ge1$ \AA\ compared to systems with $W_{\rm FeII}$ $<1$ \AA. The $N$(HI) associated with the HI 21-cm absorbers would be $\ge 2 \times 10^{20}$ cm$^{-2}$, assuming a spin temperature of $\sim500$ K (based on HI 21-cm absorption measurements of damped Lyman-$\alpha$ systems at this redshift range) and unit covering factor. We find that HI 21-cm absorption arises on an average in systems with stronger metal absorption. We also find that quasars with HI 21-cm absorption detected towards them have systematically higher $E(B-V)$ values than those which do not. Further, by comparing the velocity widths of HI 21-cm absorption lines detected in absorption- and galaxy-selected samples, we find that they show an increasing trend (significant at $3.8\sigma$) with redshift at $z<3.5$, which could imply that the absorption originates from more massive galaxy haloes at high-$z$. Increasing the number of HI 21-cm absorption detections at these redshifts is important to confirm various trends noted here with higher statistical significance.Comment: 17 pages, 10 figures, 8 tables, accepted for publication in MNRA