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The stability analysis of rock slopes has been a challenging task for engineers because the rock mass constituting the slope often has discontinuities in various forms, resulting in different types of slope failures. The plane failure is one of the rock slope failures observed in field situations when the discontinuity is in the form of joint planes. There are several parameters including surcharge and seismic loads that govern the stability of the rock slope against plane failure in field projects. The limit equilibrium approach for the estimation of the factor of safety of the rock slope against plane failure has been well accepted by the engineers in the past. Very recently, attempts have been made to present analytical expressions for the factor of safety of the of the rock slopes against plane failure, which are not in a generalised form because they do incorporate most field parameters. Therefore, in the present work, the analytical expression for the factor of safety of a single-directional anchored rock slope (SDARS) is derived, along with a discussion of its special cases in view of different practical situations. Parametric studies and design charts for the stability of the SDARS are presented, and an illustrative example is included to explain the calculation steps for the factor of safety. In order to investigate the effect of multi-directional rock anchors on the factor of safety, an analytical expression for a multi-directional anchored rock slope (MDARS) is also presented.

One of the biggest drawbacks of the wireless environment is the limited bandwidth. However, the users sharing this limited bandwidth have been increasing considerably.Space Division Multiple Access (SDMA) is a new technology by which the capacity of existing mobile communication systems can economically be increased. This paper has been presented how the capacity can be enhanced by using SDMA with smart antennas in mobile communications system. Based on Adaptive Antenna Array (AAA) technology the spatial dimension of the existing system is exploited by means of forming independent radio beams in each of the original channels. This paper analyses the comparison of average Bit Error Rate (BER) of SDMA and CDMA technique and the different ways in which SDMA can be introduced to increase the capacity of a cellular system. The probability of error is found for a standard omni directional base station antenna, and another set of curves is found for flat top beam having a directivity of 5.1dB. It is assumed that k separate flat top beams can be formed by base station and pointed each of the k users within the cell of interest. Noticing that for an average probability of error greater than 0.1 in a propagation path loss environment of n=4, the flat top beam will support 200 users, whereas the omni-directional antenna will support only 50 users. This increase the number of user is roughly equal to the directivity offered by the flat top beam system, and illustrates the promise SDMA offers for improving capacity in wireless system. Here multipath fading is not considered., Comment: Journal of Telecommunications,Volume 1, Issue 1, pp36-39, February 2010

CDMA is a multiple access method in which the user's uses spread spectrum techniques and occupy the entire spectrum whenever they transmit. In wireless communication signal-to-noise ratio (SNR) is the very important parameter that influences the system performance. Any mode of mobile transmission is not free from channel impairment such as noise, interference and fading. This channel impairment caused signal distortion and degradation in SNR.Also there are differences between uplink (forward channel) and downlink (reverse channel).Along with these differences, both the links use different codes for chanellizing the individual users. This paper simulates the expressions for the pdfs of the SNR for both uplink and downlink transmission assuming that the system is operating at an average signal-to-noise ratio is 6dB per information bit., Comment: Journal of Telecommunications,Volume 1, Issue 1, pp84-86, February 2010

Kuranchie, F. A., Shukla, S. K., Habibi, D. , Zhao, X. , & Hossain, M. M. (2014). Studies on electrical resistivity of Perth sand. International Journal of Geotechnical Engineering, 8(4), 449-457. Available here