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For some specific applications quality of the hole is much of the need and it is defined by its dimensional accuracy at entrance and exit of hole. Laser drilling is an advanced technology in drilling process, known for its accuracy, fastness and cleanliness in material removal to get the accurate hole diameters to the range of 5 microns. It gives the feasibility to drill the holes of very small aspect ratio. Nd: YAG Laser drilling process is an economical and easily regulated conventional drilling process compared to that of WEDM, punching, broaching and other prevalent destructive processes. This laser drilling technology is equipped with advanced features, provides ease of regulating the different input parameters. Some of the many input parameters that are involved in this operation are power, lamp current, pulse width, wavelength, pulse frequency etc., every input parameter has got its influence on output responses. With this consideration, experimentation is carried out selecting austenitic stainless steel known for its wide applications based on central composite design to examine the effect of laser input parameters particularly lamp current, pulse frequency, gas pressure and pulse width, on the quality of drilled holes. In total 31 experimental trials were conducted to get output responses. With response surface methodology (RSM) technique models were simulated for output responses and then compared with adequacy test. It is found that the response surface methodology predicted models are in close agreement with that of experimental values, further using evolutionary algorithms these models can be used for optimization of process parameters. Results are also useful to automate the laser drilling process.

This study was designed to evaluate the facies and petrophysical models of a reservoir interval, R700, within the Sigma Field, Onshore Niger Delta with a view to understanding the reservoir property distribution which could help in in-fill well placement. Well tops from well logs were interpreted by variations in depositional characteristics and were tied to seismic surfaces in order to construct the stratigraphic framework. Well data including facies, porosity, volume of shale and hydrocarbon saturation were scaled-up to geological grids. The pixel-based facies model was built based on normal distribution of the facies using Sequential Indicator Simulation algorithm. Petrophysical models were constrained to the facies models using Sequential Gaussian simulation algorithm. The average petrophysical parameters of the three reservoir intervals penetrated by the wells revealed the reservoirs to be of good quality with porosity ranging from 22.2-32.4%, net-to-gross; 51.9-80.3% and water saturation; 23.3-27.1%. The generated fault model of the field showed a dominant East-West trend with good connectivity/linkage. From the analysis of the structural maps and positions of existing wells, the faults can be said to play a major role in aiding accumulation and as such can be used as a guide/control in delineating other areas where accumulation can be favoured. The facies interpretation from well log and analysis of the isochore maps helped in delineating the direction of sand development and helped in constraining the facies model. The facies model captured the heterogeneity in the reservoir interval. Cross section drawn across positions of existing wells showed the location of the wells on structural highs while those drawn across other areas of the field away from existing wells but through areas of structural high revealed areas of good reservoir quality for sitting new wells for optimum recovery of hydrocarbon from the field.

This paper introduces the new form of set namely Fineutro set and lays a foundation to discuss its behavior. Also we have defined Fineutro topological spaces.

A new model of fractal geometry for microstrip patch antenna is presented in this paper. The current fractal structure is implemented on patch aperture by placing slots in a systematic order. A commercial substrate material of RT-duroid is chosen with dielectric constant of 2.2 and loss tangent of 0.009. The dimension of the patch aperture is 56.7X42.9 mm. The simulated results show that the antenna is resonating at 2.6 GHz and 2.8 GHz, which comes under Wi-Fi application and a very good performance, is observed with respect to impedance bandwidth return loss, field distributions and radiation pattern.

Implementation of generic skill in co-curriculum activities among student is to enable the country to realize National Education Philosophy in the context of producing student balanced in term of physical, emotional, spiritual, intellectual and social which will be more competitive in the advent of a borderless world. Therefore, the direction of this writing is to unravel the relationship between curriculums with generic skills in producing high-quality graduates.

A site earmarked for radioactive waste disposal facility was subjected to geophysical assessment and characterization. The principal aim was to ascertain the ‘competence’ or otherwise of the site and to determine whether or not the geological setting is stable enough to contain the waste. The investigation employed two geophysical techniques; electrical resistivity and seismic refraction surveys. The resistivity profiling survey have shown some zones of low resistivities at specific stations on all four survey lines which implies discontinuities in the rock formation suggesting the presence of geological contact. The seismic surveys have also revealed weak zones at same and close to the stations of the resistivity surveys. These weak zones suspected to be as a result of faults or fractures have been mapped. With the aid of the resistivity sounding data and that of the seismic refraction, the site was thus characterized as a four layer formation with geological contacts at certain points.

Green synthesis of Zinc Oxide nanoflowers by plant extract is currently under utilization. This research account on the exploit of aqueous leaf extract of Azadirachta indica in the biosynthesis of bioactive zinc oxide nanoflowers with aqueous solutions of zinc acetate and sodium hydroxide at ambient temperature. The aqueous extract of Azadirachta Indica can be used as a template to control particle size and stabilize ZnO nanoparticles. The ZnO nanoflowers prepared by the green synthesis exhibited a hexagonal wurtzite structure with a crystalline size of 51 nm and particle size of 100 nm. To make the process environmentally viable the reaction was carried out under solvent free conditions. Formation of zinc oxide nanoflowers was confirmed by Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction patterns and scanning electron microscopy (SEM) with Energy dispersive X-ray (EDX) patterns. The results confirmed that aqueous leaf extract of Azadirachta indica is a suitable green template to prepare heterogeneous ZnO nanoflowers. Green methods are be good competent for the chemical procedures, which are environment friendly and convenient.

Cotton fibre is one of the most preferred raw materials in apparel industries due to its natural feel and comfort. Fibre reactive dye is the colourant of choice for dyeing cotton fabrics due to its brilliancy, variety of hue and high wet fastness properties. The major challenge in reactive dyeing of cotton is that require large amount of salt for exhaustion, in addition to that extensive water used for removing unfixed dye. The unfixed dye along with added salt increases effluent load on effluent treatment plants and limits the opportunities for recycling treated effluents and cause environmental pollution. This research paper focuses on the modification of cotton fabrics in such a way that the produced fabrics dyed with reactive dyes without the addition of salt thus reduced the effluent load and make the process more sustainable and greener process.

The informal (Juakali) sector in Kenya lack occupational health and safety services and workers unknowingly exposed to health hazards. Worldwide, occupational noise is a significant cause of adult onset-hearing loss and 16% of disabling hearing loss in adults. . The aim of the study was to identify the health effects of noise to the Juakali artisans in King'orani area by identifying key sources of noise, assessing hearing threshold levels, examining auditory health effects of noise and the prevalence of noise induced hearing loss. This was through administration of a structured questionnaire, noise level measurements, and pure tone eudiometry to stratified, randomly selected subjects. Data was coded cleaned and analyzed using SPSS version 21.0. Out of 124 participants involved in the study, prevalence of NIHL was 59.7% with 31.5% having mild, 18.5% moderate, and 5.7% had severe, and 4% had profound impairments. The level of impairment increased with the duration and level of exposure to noise above 90 dB. Those involved in operation of pneumatic tools were the most affected compared to those involved in other activities as food vendors and hawkers. Exposure level and duration was greatly associated with auditory effects such as Tinnitus, headache, poor concentration, and sleep disorders. In conclusion NIHL, headaches, tinnitus, poor concentration and sleep disturbances are related to prolonged exposure to high level of noise above 90dB with a positive correlation coefficient of 0.248 at p<0.05. Therefore, review of OSHA 2007 to effectively regulate the informal sector, awareness campaign on effects of noise exposure, establishment of Hearing monitoring canters, special subsidies and provision of PPEs will be able to arrest the otherwise forgotten irreversible disability causing Hazard the Juakali artisans are exposed to.

The corrosion inhibition of mild steel in 1.0 M HCl solution was investigated using Hexamethylene tetramine (hexamine) as a corrosion inhibitor by using different techniques i.e. weight loss method, potentiodynamic polarization and Electrochemical Impedance Spectroscopic (EIS) at 35.0o C. Further, the surface study of corroded specimen was carried out by inverted trinocular metallurgical research microscopy. It was observed that the percentage corrosion inhibition efficiency increases with increase in the concentration of inhibitor. The maximum percentage corrosion inhibition efficiency was 93.0 % at a concentration of 800 ppm. Impedance study shows the increases in Rct value with increase in the concentration of inhibitor. Potentiodynamic polarization studies showed that Hexamine behave as mixed type of corrosion inhibitor. Results obtained from corrosion experiments shows that Hexamine is a very good corrosion inhibitor for mild steel in 1.0 M HCl.