IOSR-JAP   Volume-12 ~ Issue-1 ~ Jan. – Feb. 2020

ABSTRACT:In this paper, we show the control means of rectified reactive electromotor, that ensure full phase functioning regime. Into details, we study a control algorithm with direct magnetization current.

Keywords: Full phase control; Rectified reactive electromotor

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ABSTRACT Noise from a source like a chainsaw mortifies the value of our environment. Noise is known to produce many adverse effects both on humans and on structures. The distances at which the adverse effects of noise from a 1 hp chainsaw cover in the residential areas must be predicted. This work therefore presents prediction of safe operating distances for a 1 hp chainsaw in a non-work environment. Measurements of noise levels with respect to distance, x from the 1 hp chainsaw in operation were considered. The linear regression method was used in analysing the data. Environmental noise models were developed by using the relevant displayed parameters. Then, the results obtained from the models developed in this work, LH(modelled) were compared with the results obtained......

Keywords: a 1 hp chainsaw, operating distances, modeling, non-work environment, prediction

[1]. World Health Organisation (WHO), Guidelines for community noise. Retrieved June 25, 2017 from http://www.who.int/docstore/peh/noise/noiseindex.html. 1999.
[2]. Ekott, E. E.. Evaluation and Modelling of Environmental Noise Pollution in some Local GovernmentAreas of Akwa Ibom State, Nigeria. (Ph. D Thesis) submitted to the Department of Physics, University of Calabar, Calabar, Nigeria, 2018.
[3]. Menkiti, A. I. & Ekott, E. E., Determination of noise levels with respect to distance at selected workshops/factories in Itu Local Government Area of Akwa Ibom state, Nigeria. IOSR Journal of Applied Physics (IOSR-JAP), 6(3), 2014, 43 - 53.
[4]. Menkiti, A. I., Analysis of noise bother by survey method. Global Journal of Pure and Applied Sciences, 7(3), 2001, 545 - 550.
[5]. Schmidt, C. W., Noise that annoys regulating unwanted sound. Environmental Health Perspectives, 113(1), 2005, 1 – 3.

ABSTRACT: Community noise creates negative impacts both on humans and on structures. As a result of the strong biased factor in the sensitivity of noise, physical measurements of noise give only partial interpretation of the real problem. Public view is one of the most dependable indices of the problem. This paper therefore presents the evaluation of the impacts of community noise pollution in Okobo Local Government Area, Nigeria. From the results of physical measurement, some major locations in the Local Government Area were chosen as interview centres. Sources of noise such as aircrafts, tricycles/motor cycles, cars, churches, children, animals, workshops/factories, lorries, compact disk sellers, traders and ships/engine boats, power generator and night clubs were presented to the interviewees. The interviewees were then asked to tick the type(s) of noise they were exposed to and to indicate how the noise type(s) affect them. The data obtained were analysed by using Percentage Analysis Method (PAM). The results reveal that noise has negative effects on the people of the area. The results also indicate there are many sources of noise in the area.

Keywords- Community noise, evaluation, , impacts, Okobo Local Government Area, pollution.

[1]. Menkiti, A. I., Analysis of noise bother by survey method. Global Journal of Pure and Applied Sciences, 7(3), 2001, 545-550.
[2]. World Health Organisation (WHO), Guidelines for community noise. Retrieved June 25, 2017 from http://www.who.int/docstore/peh/noise/index.html. 1999.
[3]. Menkiti, A. I. & Ekott, E. E., Determination of noise levels with respect to distance at selected workshops/factories in Itu Local Government Area of Akwa Ibom State, Nigeria. IOSR Journal of Applied Physics (IOSR-JAP), 6(3), 2014, 43-53.
[4]. Schmidt, C. W., Noise that annoys regulating unwanted sound. Environmental Health Perspectives, 113(1), 2005, 1–3.
[5]. E. E., Bassey, D. E. and Obisung, E. O., Modeling the Relation Between Noise Levels and Distance from a 500 kVA Power Generator. World Journal of Applied Science and Technology, 10 (1B), 2018, 124 – 130.

ABSTRACT: Well-log data covering three wells (AA, BB and CC) in Tau(𝝉) Field in the Niger Delta were used for density-velocity constants evaluation. Using Hampson Russell Software, Gardner's and Lindseth's relations were localized and subsequently transformed to obtain the local fits constants: b, n, e and f for sand and shale lithologies. The correlation result of 𝑉𝑝 with 𝑉𝑠 is 0.93 which is a strong linear relationship; therefore, density can also be predicted using shear wave velocity data. The major findings resulting from the local fit for sands and shales differentiated, indicate b and n from compressional wave velocity as 0.23 and 0.27 (from shear wave velocity as 0.12 and 0.24) respectively for sand; 0.52 and 0.45 (from shear wave velocity as 0.23 and 0.30) respectively for shale. Also, the constants e and f from compressional wave velocity as 0.320 and 3481 (from shear wave velocity as 0.340 and 1640) respectively for sand; 0.35 and 1595 (from shear wave velocity as 0.35 and 8380) respectively for shale.

Keywords: Density, Velocity, Constants, Sand, Shale, Lithology and Well-Log Data

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[5]. George, N. J., Akpan, A. E., George, A. M. &Obot, I. B. (2010).Determination of Elastic Properties of the Over Burden Materials in Parts of Akamkpa, Southern Nigeria using Seismic Refraction Studies.Archives of Physics Research, 1(2): 58 – 71.