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Subaschandar N.,BIUST | Sakthivel G.,COMMAIR
MATEC Web of Conferences | Year: 2016

This paper presents an analysis of fluid flow in a typical manifold. A commercially available Computational Fluid Dynamics (CFD) package has been used to analyze the flow pattern inside the manifold. Pressure drop in whole fluid domain and mass flow rate in all the outlets in the manifold have been computed. Based on the preliminary results, a modification to inside of the main pipe of the manifold has been incorporated. The performance of the modified design has been compared with the original design from the point of view of average temperature and mass flow rate at the outlets. A simple modification has been shown to improve the uniformity of temperature and mass flow at the outlets. © The Authors, published by EDP Sciences.


Rajesh H.M.,BIUST | Santosh M.,China University of Geosciences | Wan Y.,Chinese Academy of Geological Sciences | Liu D.,Chinese Academy of Geological Sciences | And 2 more authors.
Precambrian Research | Year: 2014

SHRIMP U-Pb analysis of zircon grains from an ultrahigh temperature Mg-Al granulite from the northern margin of the Kaapvaal Craton (Southern Marginal Zone) shows ages of ~2.72. Ga for the peak metamorphism. Geochemical characteristics of syn-tectonic charnockites in the area are similar to magnesian charnockites, typically formed in subduction settings. In contrast to the prevailing models on peak metamorphism in the context of Neoarchean continent collision between Archean Zimbabwe and Kaapvaal cratons resulting in the formation of the Limpopo Complex, we relate the Neoarchean events to the accretion of this marginal block to the rest of the Kaapvaal Craton. In this model, the subduction event is marked by the formation of magnesian charnockites, and the ultrahigh temperature metamorphism dates the collision event. © 2014 Elsevier B.V.


Subaschandar N.,BIUST
MATEC Web of Conferences | Year: 2016

The two-dimensional asymmetric near wake behind a GAW(2) airfoil section is studied at low speeds. Mean velocity measurements have been made in the near wake. Mean velocity profiles in the near wake are presented. Also integral parameters based on the mean velocity profiles have been presented here. In the near wake region mean velocity profiles are seen to exhibit symmetry within a distance of about 60 trailing edge momentum thicknesses downstream of the trailing edge. © The Authors, published by EDP Sciences.


Subaschandar N.,BIUST
MATEC Web of Conferences | Year: 2016

Scale growth in pipe fittings is a major problem for an alumina refinery. Investigation into the scale growth mechanism at an alumina refinery found almost 60% more scale growth in concentric reducer when compared with the connecting straight pipe sections for similar flow conditions. The current study is an attempt to characterise the fluid flow inside a concentric reducer, especially streamwise and crossflow fluctuations using computational fluid dynamics methodology. The present study shows that streamwise component of instantaneous velocity fluctuation decreased and cross component of the instantaneous velocity fluctuation increased inside the concentric reducer. Present Computational results have shown good agreement with the experimental data. © The Authors, published by EDP Sciences.


Yane T.,BIUST | Subaschandar N.,BIUST
MATEC Web of Conferences | Year: 2016

Axisymmetric near wake flow behind a body of revolution has been analysed. It is shown that the logarithmic layer of the upstream turbulent boundary layer continues to be valid for some more distance in the near wake and as the streamwise distance is increased the logarithmic layer is slowly getting destroyed. It is also shown that the central line velocity exhibits a logarithmic behaviour with streamwise distance. © The Authors, published by EDP Sciences.


Subaschandar N.,BIUST
MATEC Web of Conferences | Year: 2016

The two-dimensional asymmetric far wake behind a GAW(2) airfoil section is studied at low speeds. Mean velocity measurements have been made and analysed in the far wake, where initial asymmetric wake has become symmetric with respect to the minimum velocity line. Governing equations have been solved with appropriate boundary conditions in the far wake. Self-similarity solutions have been obtained for the governing equations for the mean velocity distributions. Results of self-similarity analysis have been compared with experimental data. © The Authors, published by EDP Sciences.


Kuthadi V.M.,University of Johannesburg | Selvaraj R.,BIUST | Selvaraj R.,University of Johannesburg | Marwala T.,University of Johannesburg
Proceedings of 2015 IEEE 9th International Conference on Intelligent Systems and Control, ISCO 2015 | Year: 2015

Wireless Sensor Network (WSN) is fixed in many sensing environments to capture and monitor events. The sensing values come from sensor device that may contain noise, missing values, and redundant features. Noise, missing values and redundant features should be removed from the streamed data using an efficient preprocessing mechanism and then preprocessed data can be provided for further processing such as classification or clustering. If any errors occur in the streaming data then the preprocessing mechanisms should be able to handle the errors adaptively. Many preprocessing techniques are implemented for preprocessing streaming data, to adapt dynamic changes, and to handle different situations. The problem is the preprocessing systems does not efficiently handles different situations and adapt to changes for streamed sensor data. In this research, a new adaptive preprocessing mechanism is proposed that will efficiently handle changes in the incoming streaming data and scenarios are implemented to decouple the preprocessor and predictor in different situations for increasing the prediction accuracy. The proposed system uses PCA (Principal Component Analysis) as preprocessor and Hyperbolic Hopfield Neural Network (HHNN) as predictor. This method provides an efficient and adaptive preprocessing of streaming data. © 2015 IEEE.


Selvaraj R.,BIUST | Kuthadi V.M.,University of Johannesburg | Marwala T.,University of Johannesburg
IET Communications | Year: 2016

Nowadays, distributed denial of service (DDoS) becomes a major challenge in the network as it affects the network at multi-level. This leads to traffic overhead and wastage of bandwidth utilisation. In order to overcome these issues, ant-based DDoS detection technique using roaming virtual honeypots is proposed. In this technique, virtual roaming honeypot along with the multi-level secure architecture is used to collect the information about the various intruders at different levels in the network. Ant colony optimisation technique is used to detect the intruders based on the pheromone deposit on that considered area. A multi-level IP log table is used to detect the intruders at different levels of the network. Once the affected area is found, the information is sent to multi-level architecture to limit the spread of the affected area to the honeypot. This information is sent to the honeypot to make a defence system against the attackers. The advantage of the proposed technique is that it provides a full defence against DDoS at multi-level without creating any traffic overhead. © The Institution of Engineering and Technology 2016.


Kuthadi V.M.,University of Johannesburg | Selvaraj R.,BIUST | Marwala T.,University of Johannesburg
Advances in Intelligent Systems and Computing | Year: 2016

Numerous schemes for data aggregation are done by encryption for privacy of data, and thus, homomorphism has been reviewed and designed on the wireless sensor network (WSN) to improve security. WSN is an emerging and challenging technology in the area of the research because of its vital scope with low power energy associated with it. Several application sensors collect information or data from different sensed nodes and will be aggregated to a host computer or a base station. Data aggregation happens in a network between intermediate nodes which causes to reduce energy consumption on these nodes to make efficient network performance. The algorithm used in existing aggregation system does not provide sufficient security functionality and is more vulnerable to several attacks. Furthermore, some compromised nodes also inject false data which leads to a falsify data aggregation which is forwarded to base station. The enlargement of WSNs is thrombosed due the limited energy constraints. The main focus of this paper is done mainly on enhancing energy in WSN by working on the enhancement of some routing protocol. This paper also explains on eliminating of data vulnerability, security aggregation, and false data injecting attack by presenting different robust surveys and protocols. In this paper, initial discussions are done on WSN with a detailed overview of sensor, and reviews are made on providing security of wireless sensor network. The proposed novel idea is used in aggregating data during exchanging of messages and to preserve its data privacy and also to overcome problem in network construction (NC) and its security. The NC is done byclustering its topology, and assigning heads to each cluster with huge communication range, also security pattern generation is created for protecting the data information. © Springer India 2016.


Yang Q.-Y.,China University of Geosciences | Santosh M.,China University of Geosciences | Santosh M.,Kochi University | Rajesh H.M.,BIUST | And 2 more authors.
Lithos | Year: 2014

Charnockites (pyroxene-bearing granitoids) of magmatic origin in diverse tectonic settings and ranging in age from Mesoarchean to Cretaceous constitute important components of the continental crust. Here we report charnockites displaying both magnesian and ferroan compositions associated with gabbros from an AMCG (anorthosite-mangerite-charnockite-granite) suite in the North China Craton. The orthopyroxene in the magnesian charnockite is characterized by moderate XMg of 0.63-0.65 (Wo1-2En62-63Fs35-36), and low Al2O3 content of 0.59-0.71wt.%. The magnesian charnockites show medium- to high-K contents, and high Mg# (~47-69) similar to that of gabbros, whereas the Mg# of the ferroan charnockites is low (~6-28). The ferroan charnockites are alkali-calcic to alkalic, and weakly peralkaline to metaluminous, whereas the magnesian charnockites are calcic to calc-alkalic, and metaluminous. Although magnesian charnockites are in general considered to have formed in subduction setting, the medium- to high-K contents, high Mg# values with a wide range, and the highly negative εHf values of the zircons in these rocks (-8. 4 to -13.6), suggest inheritance of the arc signature from the melting of ancient arc-related crustal material. The ferroan charnockites show tholeiitic affinity and define a common differentiation trend with the gabbroic anorthosites and likely represent fractionated end-members with or without crustal interaction in a post-collisional rift setting. We present U-Pb age data from zircon grains on seven samples including two ferroan charnockites, three magnesian charnockites, one gabbroic enclave in magnesian charnockite and one gabbroic anorthosite which show emplacement ages of 1748.8 ± 6.4Ma, 1747.1 ± 9.5 Ma, 1756.4 ± 7.3 Ma, 1756.7 ± 9.2 Ma, 1731 ± 17 Ma, 1731.6 ± 8.2 Ma and 1746.5 ± 7.3 Ma respectively. The negative εHf values (-1.2 to -13.6) of zircon grains from these rocks and the older crustal model ages ranging from Mesoarchean to Paleoproterozoic suggest that the magma sources of these rocks involved the melting of ancient crustal components. The age data suggest that the magmatic suite was emplaced within a relatively short time interval between1.73 and 1.76Ga, during late Paleoproterozoic, placing the rocks suite in a post-collisional scenario, following the amalgamation between the Eastern and Western Blocks of the North China Craton along the Trans-North China Orogen at ca. 1.85-1.80Ga. © 2014 Elsevier B.V.

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