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

[1]. Atat, J. G., Akpabio, G. T., George, N. J. &Umoren, E. B. (2012). Geophysical Assessment of Elastic Constants of Top Soil using Seismic Refraction Compressional Velocities in the Eastern Niger Delta. International Journal of Modern Physics, 1(1): 7 – 19.
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[3]. Ekweozor, C. M. &Daukoru, E. M. (1994).Northern Delta Depobelt Portion of the Akata-Agbada Petroleum System, Niger Delta, Nigeria. In: Magoon, L. B. & Dow, W. G. Editions. The Petroleum System from Source to Trap.American Association of Petroleum Geologists Memoir 60. Tulsa: American Association of Petroleum Geologists, pp. 599 – 614.
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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.

ABSTRACT: Glass of the system: (50-x) P2O5:10Li2O: 15PbO:25 B2O3: xTm2O3. (where x=1, 1.5,2 mol %) have been prepared by melt-quenching method. The amorphous nature of the glasses was confirmed by X-ray diffraction studies. The physical parameters like density, dielectric constant and electrical susceptibility have been evaluated. Dielectric constant, refractive index, electronic polarizability varies with increasing mole% of Tm2O3 respectively. The metallization criterion has been calculated on the basis of refractive index and energy gap. It was found to be decreased with increasing refractive index and decreasing energy gap. The large value of metallization criterion indicates that the glass materials are insulators.

Keywords: Thulium based glass; Electrical Susceptibility; Metallization criterion

[1]. Reddy,A. A. , Sekhar, M. C. , Pradeesh,K. , Babu, S. S., Prakash,G. V. (2011).Optical properties of Dy3+-doped sodium-aluminumphosphate glasses, J Mater Sci, 46, 2018-2023.
[2]. N. Aboulfotoh et al(2014). Charaterization of copper doped phosphate glasses for optical applications. Ceramic International.40: 10395-10399.
[3]. CR Kesavulu et al (2010). EPR, Optical Absorption and Photoluminescence Properties of Cr3+ ions in Lithium Borophosphate Glasses. Journal of Alloys and Compounds. 496: 75-80
[4]. Seneschal, K.; Smektala, F.; Bureau, B.; Le Floch, M.; Jiang, S.; Luo, T.; Lucas, J.; Peyghambarian, N.( 2005).Properties and structure of high erbium doped phosphate glass for short optical fibers amplifiers. Mater. Res. Bull. 40, 1433–1442.
[5]. Miniscalco, W.J.(2001). Optical and electronic properties of rare earth ions in glasses. Rare-Earth-Doped Fiber Lasers andAmplifiers, 2nd Edition,Marcel Dekker, NewYork, Basel, (2001).

ABSTRACT : Thirty rock samples from Al-Qusair area in Egypt have been investigated. The naturally occurring radionuclide contents have been measured by gamma-ray spectrometry employing a shielded HpGe detector. The activities of 238U, 232Th and 40K have been determined in Bq Kg-1. The activity concentrations of 238U, 232Th and 40K were ranged from (15.41±1.67) to (326.94±4.40), (2.05±0.98) to (25.58±3.40) and (39.02±3.98) to (654.94±14.42) Bq Kg-1 respectively. Radium equivalent activities, absorbed dose rate and the values of hazard indexes were calculated for the studied rock samples to determine the radiation hazards arising from those samples. The absorbed dose rate values were found to vary from 31.26 to 149.72 nGy h-1. The radium equivalent values for the investigated samples are less than the international average value 370 Bq Kg-1. The present results have revealed that the radiological parameters are normal and within the international levels. This study provides a base line map of radioactivity background levels in the Egyptian environment and could be used as reference information to assess any changes in the radioactive background level due to the geological process....

Keyword: NORM; Absorbed dose; Hazard index; Radium equivalent

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ABSTRACT: The objectiveof this workis to compare betweenthe calculated dose by treatment planning system (TPS) and the measured dose collected by ArcCHECK phantom,for prostate cancer patients with two techniques:Volumetric Modulated Arc Therapy (VMAT) and Intensity Modulated Radiation Therapy (IMRT) using 3DVH system (Sun Nuclear Corporation, Melbourne, FL, USA). ArcCHECK is a 3D dosimetry quality assurance (QA)toolusedto measure the doses that are calculated by a (TPS)and compares them with the measured dose from the linear accelerator. The 3DVH is a measured dose(QA) software application used for comparing 3D dose and dose volume histograms (DVHs). One dataset is imported as a reference dose plan by(TPS), and the other is calculated by 3DVH from a correction of the intended TPS dose plan by ray tracing corrections that have been determined with.....

Keywords: 3DVH, QA, ArcCHECK, Gamma Pass Rate

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[5]. J. H. Park, T. G. Kim, S. K. Min, and B. Do Park, "Comparison of 3DVH Software with Two-dimensional Array Systems on Pretreatment Verification for Volumetric-modulated Arc Therapy," J. Nucl. Med. Radiat. Ther., vol. 07, no. 02, 2016.

ABSTRACT: The development of a solar concentrator dryer using locally made materials consisting of three main components: the drying chamber, the solar collector and the absorber. A constructed measuring device with logger which is the electronic system was used to monitor the temperature, moisture content and light intensity during the drying process. The device consists of sensors for sensing temperature (LM 35), light intensity (phototransistor) and moisture level (moisture changing resistor). As the intensity of the sun increases, the temperature of the dryer begins to rise and the rate of evaporation in the solar concentrator dryer is higher the evaporation rate in the open sun. The dryer drying process reduced the moisture content of 500 g of sliced white yam from 73.20% (wet basis) to 4.29% (wet basis) for 20 hours despite the poor weather condition when the experiment was carried out..

Keywords: solar conconcentrator dryer, electronic monitoring system, yam.

[1]. Ajao, K. R. and Adedeji, A. A. (2008). Assessing the drying rates of some crops in solar dryer. Journal of Research Information in civil Engineering, 5(1):1-12.
[2]. Akowuah, J. O., Addo, A. and Bart-Plange, A., (2012). Influence of Drying Temperature and Storage Duration on Fissuring and Milling Quality of Jasmine 85 Rice Variety. Journal of Science and Technology, 32(2): 26-33
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[5]. Babamiri, N. S. and Asli-Ardeh, E. A., (2013). Effect of Drying Temperature and Final Grain Moisture Content on the Hulling and Head Rice Yield Efficiency of Some Common Rough Rice Varieties. International Journal of Agriculture and Crop Sciences, 6 (9): 529-533.

ABSTRACT: The results of the effect KI addition to phase identification, critical temperature and electrical resistance in FeSe superconductors are reported. The synthesis process of FeSe superconductors is done conventionally by hand milling for 3 hours followed by a solid state reaction at 845°C for 3 hours and cooled in the open air. Structurally, KI addition to FeSe superconductors material was found to reduce the volume fraction of the main (tetragonal) FeSe superconductors from 85.66% to 79.28% at the addition of 1 wt % and 60.36% at the addition of 5 wt % FeSe superconductors namely 13.33 K to 12.27 K. In this report, we discuss the phases formed, the morphology of the doped material and the resistivity value of each as a function of temperature varying from 5 K to room temperature

Keywords: FeSe Superconductors, KI Addition, Temperature

[1]. Kamihara Y, Watanabe T, Hirano M, and Hosono H. 2008. Iron Based Layered Superconductor La[O1-XFX]FeAs (x = 0.05–0.12) with Tc = 26 K. American Chemical Society, 30: 1-2.
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ABSTRACT: A hypothetical model is accounted for to compute the warm conductivity of nanomaterials in various shapes, for example, round nanosolids, nanowires and nanofilms dependent on size subordinate nuclear strong energy on thinking about the surface impacts. It is seen that the warm conductivity of various shapes nanosolids diminishes with decline in the grain size. The outcomes acquired are contrasted and the accessible test information. A nearby arrangement among hypothesis and investigation support the legitimacy of the strategy talked about.

Keywords: grain-size, nanomaterials

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