Volume 6, Issue 9, September 2015 Edition

Publication for Volume 6, Issue 9, September 2015.

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Groundwater characterization and impacts on health and environment in Abakaliki area and environs, Southeastern Nigeria[ ]


Water quality and availability is a consequence of the natural physical, chemical and biological state as well as any other alterations that may have occurred as a result of biotic and abiotic activities. The usefulness of water for a particular purpose is determined by the status of these parameters. In view of this, an understanding of these factors influencing livelihood is pertinent. In this study, hydrologic and hydrogeological characteristics as well as chemical and biological status of both surface and groundwater were evaluated. World Health Organization (WHO) standard were used as the yardstick to characterize the chemical and biotic status. Further, the Piper’s Trilinear technique is employed. A questionnaire approach was also used to simulate water status impact on livelihood.

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Laser performance of some polymeric-state laser dyes in transversely resonating cavity[ ]


Pyrromethene laser dyes (PM567 and PM597) and Rhodamine 6G (R6G) were doped in 2-hydroxy ethyl methacrylate (HEMA) and methyl methacrylate (MMA) to form copolymer host of composition (1:1; v/v). optical and photo-physical properties such as;the oscillator strength (f), the transition dipole moment μ12, the attenuation length Λ(λ), the energy of fluorescence (Ef), radiative decay rate (Kr) and intersystem crossing rate (Kisc) showed that, R6G in polymeric host has the highest values which gave indication of its higher laser performance than other PM's dyes. 2x10-3mol/L was the optimum concentration of the laser dyes in this polymer host. At this concentration, PM567, PM597 and R6G have laser performance values (by transversely resonating cavity) 51.1%, 52.0% and 54.3% respectively. Also, the photostability of the optimum concentration of the three laser dyes in solid host was studied.

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Expansion of Power System Corridors Using Tier-1 Technique for Reactive Power Compensation[ ]


This paper develops a novel strategy for the expansion of the power system corridors for the release of the embedded transmission capacity. Both theoretical and practical network models are presented with a focus on power flow studies which concentrates on the steady state or static behavior of electrical power system. The methodology involves the power flow analysis revalidation of the existing standard IEEE 14 bus system and simulation using Newton-Raphson method in both MATLAB and Powerworld simulator (PWS) environment. This paper therefore establishes that an original designed network could be modified to take more loads without building new generators or transmission lines. The expansion of the existing IEEE 14 bus network to accommodate more load involves the use of static compensators incorporated at the transmission lines. This technique is then analyzed extensively when distributed along the lines through the use of a distributed capacitors compensators, (DCC). DCC can affect significant change in power line impedance to improve the power transfer capacity of an interconnected power system. The application of the DCC on the line is the tier-1 technique. The results obtained show that by applying the tier-1 techniques to the transmission line, the system’s capacity will remarkably improve and the transmission line will accept extra loading.

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Mechanical and Metallurgical Behaviours of Nitrided Aircraft Shaft[ ]


Nitriding is a thermo-chemical process by which the surface of a ferrous metal is enriched with nitrogen to improve the wear resistance along with anti galling properties, high surface hardness, improved fatigue resistance, better creep resistance and enhanced corrosion resistance of the components. The Nitriding technology shows a clear orientation towards future developments. Hence, it ideally satisfies current and future industrial demands for economical and efficient solutions to the treatment of surfaces. It is also an answer to social demands for improved environmental protection. So that, it has act as a major role in manufacturing of automotives, railways, aircraft and aerospace components such as engine assembly parts, tappets, valves, bearings, shafts, Piston Pins, Spacers, rods, Screws, Washers, Nuts propeller control and power control Systems, etc., In the present, we are interested to study the mechanical and metallurgical behaviours of nitrided aircraft shaft, which is newly designed by the theoretical modeling of Solid Works Simulation Xpress Study and the same practically developed by using of Plain Carbon Steel i.e. AMS 5069 /AISI 1018 and also we would like to enhance their Mechanical Properties with help of Nitrding. After Nitriding, the qualitative analysis was done by Rockwell Hardness Testing, Microstructure Examinations, Case depth and Compound Zone Determinations, etc., The obtained results are compared and conclude whether the chosen material is suitable for producing the Aircraft Shaft by the way of economy.

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A Parametric Study for the Optimal Design of Barrages[ ]


The barrage is a major diversion structure involved in canal head works and meant for local ponding and regulating river water level. The cost of a barrage will vary for different values of design parameters which address different types of soil and hydrological conditions and that govern barrage profile dimensions. In this paper a parametric analysis was conducted to investigate the effect of variation in the design parameters values on the dimensions and on overall cost of the barrage with utilization of the optimization approach to find optimal hydraulic design of the barrage. It was showed that the flood discharge have the greatest effect on the total cost of the barrage and a barrage constructed on fine grained soil is costlier than that constructed on a foundation of coarser bed material.

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MAPPING AND ANALYSIS OF TECTO-LINEAMENTS OVER PARTS OF NORTH EAST-ERN NIGERIA, WEST AFRICA[ ]


Lineaments are essential for understanding the structural geology as well as for mineral prospecting. A manual digitization technique was used to extract lineaments from Landsat images. Lineaments properties such as lineaments number, orientation, length, relative abundance as well as statistical relationship between lineament length and orientation were studied. The NE-SW lineaments dominate the study area. Such lineaments can be attributed to the opening of the Benue Trough. Statistically, the NW-SE lineaments and E-W lineaments are more correlating in terms of lineaments. These lineament pair is more correlating in terms to the N-S lineaments than the NE-SW lineaments.

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Performance Enhancement of DCF Based Wavelength Division Multiplexed Passive Optical Network (WDM-PON)[ ]


We Proposes a Dispersion Compensation Fiber (DCF) based Wavelength Division Multiplexed Passive Optical Network (WDM-PON) architecture which is demonstrated/simulated to provide 20Gb/s downstream and 20Gb/s upstream bandwidth. This prototype system provides good Q-Factor and acceptable BER for 50Km that is significantly higher than Conventional architecture.

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A comparison of heuristics algorithm for load balancing in cloud environment[ ]


Cloud computing, has boomed technology in new era. The main reason for its growth is its capacity to store large amount of data. We store data in digital and to store their data we require large number of storage and computer resources. Its provides a solution of this problem, as it store all software, platform and infrastructure in the data center and these all are easily accessible through internet, through the service provider at anytime and anywhere. The main objective of the work is to find an enhanced algorithm through compression various cloud load balancing algorithms since in cloud job arrivals pattern is not predictable. This paper shows the comparison of various load balancing algorithms like round robin, equally spread current execution load and throttled in cloud environment with different metric like Response time, Data processing time, cost. The considered uniqueness has an impact on cost, which can be obtained by enhanced response time and processing time. We use CloudAnalist simulation tool to show the table and results.

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Overview of user interfaces used in load lifting devices[ ]


Lifting cranes play a key role in industry. They are used all over the world on construction sites, ships, transport, ports, warehouses and wherever it is necessary to move heavy objects or goods. To control them are hired qualified people who undergo rigorous training. Lifting devices are designed to increase the efficiency of their work and minimize the risk of accidents. But between the operator, and lifting device is an underestimated element. That element determines the performance of lifting equipment and safety in places where they are used. It is a control device - the user interface, which should be the most intuitive, efficient and ergonomic, especially nowadays where time saving is very important.

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Biomass to Biofuels: Conversion Processes and Challenges in Second-generation Technologies[ ]


This paper illustrates the latest advancements in the opportunity of using biomass as an alternative source of energy to produce biofuel products. The high demand on fossil fuels should be embraced by studying available biomass feedstocks such as starch and lignocellulosic. This study shows that every feedstock can produce a unique biofuel type. In fact, lignocellulosic is the core material to produce biofuels from non-food biomass sources, known as the second-generation, where this route is more efficient and environmental friendly. However, gasification and pyrolysis are the most common techniques to convert biomass into chemicals. Thus, the characteristics of various reactors have been discussed to show that the reactor selection depends on the desired product as well as the feedstock state. Ethyl tertiary butyl ether (ETBE) and Fatty acid methyl esters (FAMEs) are the prime biofuel products from biomass. Moreover, more evaluations and studies were performed regarding the oxygen feedstock and large-scale of second-generation issues. It is possible to remove oxygen totally or partially to increase the total amount of produced energy, but this may result in the formation of charcoal or hydrogen.

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Experimental and Social study on Solar PV Characteristics and Maximum Power Point Tracking of a PV Source[ ]


The study was conducted at IIT Bombay,India. Today around 25000 villages in India [1] and 1.1 billion people in the world [2] are facing acute shortage of energy. In this ever growing economical world, solar energy provides a better clean alternative as an energy source. However due to high costs of purchase and installation this technology is not able to reach the remote and rural areas of the world which still run on traditional fuel sources. Thus there is a need to research and harness the maximum potential of solar energy. The project’s main objective was to extensively study characteristics of Solar PV modules and conduct experiments of Maximum Power Point Tracking (MPPT) used in Solar PV modules for varied radiations. In the experiment, I used a solar PV panel and a variable resistor, to extract the graphs of P-V (power-Voltage) and I-V (current-voltage) and to find out the point at which the graph yielded maximum power output from the Solar Panel. As a further extension of the project I have studied the applications of Solar Cells and their proper implementation in an Indian context.

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Shaking Table Tests on a Physical Model of a Concrete Gravity Dam[ ]


This research is devoted to experimental investigations on response of a concrete gravity dam to seismic excitations including dam-reservoir-foundation interaction. The research consists of a series of 1g shaking table tests conducted on the scaled model of the gravity dam. The experiments are conducted at the Physical Modeling Laboratory of School of Civil Engineering, University of Tehran. A parametric study is achieved through change of relative density (Dr) of ground soil. Two tests, namely, Test-1 and Test-2 are conducted on shaking table device on Dr=80% and 60 %, respectively. Also 3-phases of accelerations, namely, 0.15g, 0.3g, and 0.6g are conducted in each test. The presented data include acceleration, pore water pressure, soil pressure, dynamic water pressure and displacement records. The results are analyzed and they are suitable for comparisons with numerical ones.

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Experimental and Economical study on applications of Biogas and Biodiesel[ ]


Today there is acute shortage of energy sources all around the world. With India alone standing a debt of $6.5 billion from oil rich Iran[1], many countries in the world are facing energy crisis. Like India, China experienced severe energy shortages towards the end of 2005 and again in early 2008. During the latter crisis they suffered severe damage to power networks along with diesel and coal shortages [2]. Supplies of electricity in Guangdong province, the manufacturing hub of China, are predicted to fall short by an estimated 10 GW. Thus there is a need to resort to alternative fuel sources. Biofuel presents one such example of clean burning, economical and renewable alternative fuel. Thus the main objective of the project is to evaluate the different applications of Biogas and Biodiesel and their proper and economical implementation in developing countries so that the growing economies can become more independent from fast depleting traditional fuel sources. For this purpose, a study on using biodiesel to power fishing boats (through B2, B5, and B20 engines) has been carried out. Further a comparative study of the usage of biogas, kerosene, firewood and LPG for domestic purposes has been conducted keeping in mind the economics, pollution effects and efficiency.

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Health system monitoring using Health Management Information System (HMIS) in India and suggested enhancements to this platform[ ]


This paper is an attempt to highlight features of Government of India’s e-portal, HMIS (Health Management Information System) & comparison with some of the existing data collection processes used in health sector. Global practices and steps required to be taken for strengthening health MIS are also highlights of this paper. There is also emphasis on how an effective MIS increases the efficiency of senior and middle level health officials thereby facilitating planning and policy making decisions based on factual information.

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Indian Paper Currency Authentication System-A Quick Authentication System[ ]


Automated paper currency recognition system can be a very good utility in banking systems and other field of commerce. Since many years counterfeiting of paper currency challenges the financial system of every country in different sectors, India is also one of them. In this article, recognition of paper currency with the help of digital image processing techniques is described. Six characteristics of Indian paper currency are selected for counterfeit detection included identification mark, security thread , watermark ,numeral watermark, floral design and micro-lettering. The characteristic feature extraction is performed on the image of the currency and it is compared with the characteristic features of the genuine currency. The decision making is done by calculating the black pixels. This article is aimed to design a low cost system and quick decision making system.

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Synthesis and Characterization of Nano Hydroxyapatite with poly ethylene oxide nanocomposite for biomedical applications[ ]


The aim of this study is to prepare and characterization of hydroxyapatite with polymer nano composite. In this present study, we have developed wet chemical precipitation method for preparing nHAp with Polymer powder. It is well known that wet chemical precipitation method have several advantages for producing ceramic particularly high crystallinity, high purity, nano size and high reactivity. HAp with polymer is an important inorganic biomaterial which has attracted the attention of researchers related to biomaterial field in recent years. In this work, poly ethylene oxide with hydroxyapatite nanocomposite were analyzed and confirmed by Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), thermal analysis of TG/DTA and the consequence of this investigation suggest that the nHAp with poly ethylene oxide can be used to antibacterial agent for developing new pharmaceutical to control studied human pathogenic bacteria responsible for severe illness.

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Application of Plaid Algorithm to Identifying Patterns in Breast Cancer Gene Expression Data[ ]


Numerous studies have correlated variation in gene expression between individuals to phenotypic diversity in breast tumors. The main goal of this study was to conduct plaid algorithm to biclustering of breast cancer gene expression data with the aim of identifying tumors subgroups with similar clinical features. The real dataset that had been used in this research is the one which was used in Breast cancer (docetaxel resistance) article in 2005 that was included in CGED. Gene expression profiling was done with on data matrix containing 44 patients and 2453 genes. Plaid algorithm was used to recognize gene expression patterns, after that, percent of significant genes in each bicluster was calculated with FDR. Biclustering algorithm has discovered 265 co-expressed genes which was divided to 6 subgroups with similar expression levels. 175 number of these genes was identified significant by FDR and expression levels were different in responder and non-responder. Randomization test and GO ontology did confirm the results of biclustering algorithm. The increasing clinical use of genomic profiling demands identification of more effective methods to segregate patients into prognostic and treatment groups. We have shown that biclustering can be used to select optimal gene sets for determining the prognosis of specific strata of patients.

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PARTIAL REPLACEMENT OF CEMENT IN MORTAR BY USING RED MUD AND RICE HUSK ASH[ ]


In the modern world of high competition and environmental awareness, it has become necessary to find an alternative materials that can be widely used. With a similar views in mind, in the present study, the red mud and rice husk ash are used in partial qunatitites with the cement in mortar. With the ambit of the mechanical strength of the cement, the compressive, tensile and flexure behavior of the mortar specimens are studied and presented. The parent objective of the present study is to suggest possible percentage of use of red mud and rice husk ash along with cement which will help to reduce the cement consumption in construction industry.

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Quantifying Some Simple Chaotic Models Using Lyapunov Exponents[ ]


Lyapunov exponents are used to quantify various dynamical systems which have been found to display chaotic behaviour by embedding them in a common structural framework.

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Retinal Vessel Segmentation Using Crest Lines and Morphological Operations[ ]


Retinal vessel segmentation algorithms play an important role for the detection of numerous diseases, such as diabetic retinopathy, glaucoma and many others. The aim of this paper is report an automated method for segmentation of retinal blood vessels using the crest lines and morphological operations. Initially, each image is preprocessed and the green channel is obtained. Then, we extract the vessels crest lines using a parallel thinning algorithm for grayscale images, simultaneously we perform the sum of top-hats transforms using a linear structuring element in eight directions. Both of these two techniques are performed in the green channel of the input image. The final steps consist in intersecting the two resulting images, smoothing the borders and removing spurious objects remaining. The proposed method is simple and presented robustness and high performance on the DRIVE retinal database.

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CORDIAL LABELING FOR DIFFERENT TYPES OF SHELL GRAPH[ ]


The aim of this paper is to introduce the cordial labeling for different types of shell graphs like path joining of shell graph, star of shell graph, multiple of shell graph, cycle of shell graph and to provide some results on it.

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ANALYSIS OF THE COMPLEXITY OF THE FORMALIZED CIRCUITS OF RAYCHEV[ ]


In this study is carried out an analysis of the classical and quantum complexity of the defined by the author formalized circuits and is shown, that the circuits require several classic computations. The formalized circuits of Raychev have almost the same quantum complexity as the non-general circuits. Since the represented circuit models are independent of the techniques for matrix decomposition and the processes for global optimization, used to find the quantum circuits for a given operator, on quantum computers can be made simulations with a high accuracy for the unitary propagators of molecular Hamiltonians. As an instance, we show how to be constructed a circuit model for a hydrogen molecule.

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APPLICATION OF THE FORMALIZED CIRCUITS[ ]


The purpose of this article is to analyze the practical applications of the reconfigurable formalized circuits of Raychev, as well as to analyze the ability of the defined by the author formalized computing models for performing of scientific computations.

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Multi-functional formalized quantum circuits[ ]


To become practically and functionally viable quantum computers they should be able to use a technology for formalization of a set of operators that is of vital importance to be able to mimic the behavior of the quantum parallelism. In this study is offered a methodology to perform mapping of the quantum algorithms for designing of effective formalized quantum hardware schemes. The model is designed with consideration for implementation of superpositions and entangled input states. The proposed models provide guidelines to conduct accurate researches based on formalizations of quantum hardware schemes for practical quantum applications.

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Optimization of Cropping pattern using Linear Programming Model for Markandeya Command Area[ ]


Agriculture is one of major activity in INDIA. Overall development depends on food production in service of existing or growing population with maximum benefits and optimal utilization of water and land resources. Management of this water and land resources is also one of the main financial development. Hence there is necessity of implementation of techniques in optimum usage of such available resources. Also Keeping in view of socio economic conditions, the present study makes an attempt to develop optimum cropping pattern with the constraints of available resources like water usage and also labour, fertilizers, seeds, etc., and ultimately getting maximum net benefits. The objective function for multi crop model are formulated using LP for maximizing the net benefits, by keeping all other available resources (such as cultivable land, seeds, fertilizers, human power, pesticides, cash etc) as constraints.

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EFFECTS OF GAS METAL ARC WELDING PARAMETERS ON THE CORROSION BEHAVIOUR OF AUSTENITIC STAINLESS STEEL IN ACIDIC MEDIUM[ ]


In this work, the effects of gas metal arc welding parameters on the corrosion behaviour of type 304 austenitic stainless steel (ASS) immersed in hydrochloric acid medium (0.5M) at ambient temperatures were studied using design expert software, Scanning Electron Microscopy (SEM) and Monsanto Tensometer. The design expert was used to determine the surface responses and interactions between the parameters, SEM was used to examine the test specimen’s microstructural analysis after immersion in the corrosive medium while the Monsanto Tensometer was used to examine the materials optimum performance in hydrochloric acid medium in terms of strength and it was found that tensile strength increased with increasing welding parameters (from 120MN/m2 to 133MN/m2). It was also found that increase in welding current and speed at constant voltage gave the optimum performance of the ASS structure in HCl medium obtained at speed 40mm/sec and current 110Amp. This shows a corresponding minimal material deterioration. Surface corrosion deposit composition was analyzed with the SEM paired with energy dispersive spectrometer (EDS). It was concluded that relatively high speed and current at a constant voltage gave a satisfactory weldment with good integrity.

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EXPERIMETAL INVESTIGATION ON SOLIDIFICATION RATE & GRAIN SIZE FOR CENTRIFUGAL CASTING[ ]


In the case of centrifugal casting the molten metal occupies into the cavity by virtue of the centrifugal force. Horizontal centrifugal casting is the process of production of cylindrical components and in the same casting with different mechanical properties through the section [1]. The experiment set up is designed and this set up consists of a stainless steel cylindrical mold which is fixed both sides by a driving flange. This driving flange connected to the mold in a temporary manner with the help of nut and bolt. The DC motor can be varied up to 1400 RPM. For this analysis lead is used as molten metal because lead melted at very low temperature. Numerical simulations are carried out using the ABAQUS program which treated as an attractive and useful tool for modeling centrifugal casting process. There are numerous procedure constraints impact the appearances of the centrifugal castings such as pouring temperature of the molten metal, die wall temperature, rotational speed of the die, centrifugal force these processes. By means of the centrifugal force and rapid solidification rate the finer equiaxed grain structures are formed to obtain homogeneous and isotropic mechanical properties [1].

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Preliminary Investigation on Modification of Agbabu Natural Bitumen with Some Polymeric Materials[ ]


Bitumen is a very versatile engineering material used in road pavement. Bitumen when used in its natural form in road pavement suffers premature failure as a result of its exposure to some environmental factors such as water, light, heat, etc. Modification of the natural bitumen via addition of any additives such as polymers to its structure prior to its use in road pavement is one of the ways by which the service life of bitumen is improved.

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Synergistic Effect of Allium sativum (garlic) and Zingiber officinale (ginger) against Escherichia coli and staphylococcus aureus[ ]


The soxhlet ethanolic extracts of Garlic (Allium sativum) and Ginger (Zingiber officinale) were subjected to phytochemical screening. The result revealed the presence of Alkaloids, Saponins, Cardiac glycosides, Steroids and Flavonoids in both plants while Tannins was absent in Allium sativum but present in Zingiber officinale. The antibacterial activity of the plant extracts was assayed by the agar well diffusion method. The test isolates were Staphylococcus aureus and Escherichia coli both of which are clinical isolates. Both extracts had strong antibacterial activity against the isolates with Escherichia coli having the highest zone of inhibition with Garlic (24.00mm) and Staphylococcus aureus with Ginger (28.00mm).the minimum inhibitory concentration of both extracts was 10-2 while the minimum bactericidal concentration of both extracts was 10-1. The synergistic effect of both extracts gave a stronger activity with Staphylococcus aureus being more susceptible with a zone of inhibition of 39.00mm and Escherichia coli having 34.60mm. This confirms the use of the plant extracts in the treatment of ailments caused by these microorganisms.

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Spectrum Sensing Techniques for Cooperative Cognitive Radio Networks to Guarantee Primary User Performance[ ]


Cognitive radio technology has been proposed to improve spectrum efficiency by having the cognitive radios act as secondary users to opportunistically access under-utilized frequency bands. Frequency spectrum sharing between licensed primary users (PUs) unlicensed secondary users (SUs) requires the SUs reliably detect the spectrum occupancy. Spectrum sensing, as a key enabling functionality in cognitive radio networks, needs to reliably detect signals from PUs to avoid harmful interference. However, due to the effects of channel fading/shadowing, individual SUs may not be able to reliably detect the existence of a PU so that multiple SUs can cooperate to conduct spectrum sensing. In this paper, we derive an optimal voting rule for any detector applied to cooperative spectrum sensing such that minimizing the Bayes risk function. Furthermore, we derive an algorithm to optimize the energy detection threshold for the cognitive users for any fusion rule. Furthermore, we propose a new algorithm that determines the optimum fusion rule and optimum threshold that minimizes the false alarm probability such that the missing probability under constrains (bounded error).

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SEX, EMPLOYMENT STATUS, ACQUIRED HIGHER EDUCATION AND LABOUR FORCE CONTRIBUTION OF UNIVERSITY GRADUATES[ ]


The aim of this study was to ascertain the influence of sex, employment status, and higher education on university graduates’ labour forces contribution. 79 male 58 female university graduate draw through convenience and snowballing techniques from all university graduates in south-south Nigeria participated in the study. Three hypotheses were formulated to guide the study. Five likert questionnaire were used to collect data. The data collected were analyzed using t-test and chi-square statistics. The result obtained indicated sex, employment status and higher education to differently influence the labour market contributions of male and female university graduate. Specifically, men’s contributions were higher than women’s relative to sex, higher education attained, and employment, government, private sector employment job situations. That of the women was only higher than that of the men under self-employed conditions.

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A DETERMINISTIC INVENTORY MODEL FOR DETERIORATING ITEMS WITH LINEAR DEMAND[ ]


The present paper deals with an inventory model for deteriorating items in which planning horizon is finite. The deterioration is taken as time dependent, demand is linear function of time and production rate depends both on inventory level & demand. The analytical development is provided to obtain the optimal solution to minimize the total cost per time unit of an inventory control system. Numerical analysis has been presented to accredit the validity of the mentioned model.

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Dynamics of Infinite and Finite Bubbles Induced by Geometrical Constraint[ ]


We present an experimental study and characterise the dynamics of the propagation modes that occur due to the displacement of a viscous uid by nite and in nite bubbles from microchannels with centered rectangular occlusions. The centered rectangular occlusion results in a family of steadily propagating ngers/bubbles analogous to the propagation modes recently reported by [15, 16, 17] in millimetre-scale tubes, indicating that gravity is not an essential physical mechanism that underpins the emergence of these states.

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Design of a Novel Proactive Link State Routing Approach to Defense against Node Isolation Attack in MANETs[ ]


Routing protocols designed for MANETs are, in general, highly vulnerable to various forms of security attacks. A routing protocol is vital to the functioning of a wireless ad hoc network, and hence, security needs to be present to negate any potential malicious influences. However, providing efficient security mechanisms for such routing protocols is still viewed as being a considerable challenge. In this paper, the focus lies on the Optimized Link State Routing (OLSR) protocol, a proactive protocol which relies heavily on broadcast transmissions. This paper investigates end-to-end security mechanisms for the OLSR protocol, with specific interest in the denial of service attack. This paper proposes an extension to the standard OLSR approach called Enhanced OLSR (EOLSR) to overcome the DOS attack by using route reply messages in addition with route request messages.

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