International Journal of Science for Global Sustainability最新文献_第8页

A Review on the Effects of Radio Refractivity and Atmospheric Parameters on Signal Quality at Ultra High Frequency (UHF) 无线电折射率和大气参数对超高频信号质量影响的研究进展

International Journal of Science for Global Sustainability Pub Date : 2020-07-27 DOI: 10.57233/ijsgs.v6i2.112

Sa’adu, L., Bawa, M., Bello, M.

{"title":"A Review on the Effects of Radio Refractivity and Atmospheric Parameters on Signal Quality at Ultra High Frequency (UHF)","authors":"Sa’adu, L., Bawa, M., Bello, M.","doi":"10.57233/ijsgs.v6i2.112","DOIUrl":"https://doi.org/10.57233/ijsgs.v6i2.112","url":null,"abstract":"Refractivity is an important factor in predicting the performance of radio link. The structures of the refractive index of the troposphere are responsible for many complicated mechanisms such as, multipath effects, absorption, scattering of radio signals, etc. and these mechanisms can cause a lot of propagation impairment such as, loss of signal for mobile communication, the accuracy of tracking radio source (such as stars) with radio telescopes, radar system etc. Understanding the effects of the weather on radio wave propagation will help to improve the quality of radio signals, as the Weather variables are useful ingredients in the predictions of refractivity distributions and the anomalous radio wave propagation conditions of the atmosphere. This study contends that refractivity variations significantly affects received signal strength at Ultra High Frequency (UHF) and gave a brief theoretical background on Electromagnetic wave, Atmospheric effects on radio propagation anomalous propagation condition and the mathematical expression for refractive index and refractivity of the troposphere. Also, the paper review related articles in the following area; refractive index and refractivity of the troposphere, effects of weather variables and refractivity of troposphere. The analysis of the review articles summits that, refractivity reveals seasonal variations with high value in rainy season and low values in dry season. Also observed from the review articles, is that the diurnal variations are influenced by three atmospheric parameters; water vapour has the greatest effect on refractivity variations followed by temperature and pressure. Furthermore, the Refractivity is function of local meteorological parameters. Eventually, the study suggests that, the effect of Atmospheric parameters and consequently the Radio Refractivity should be compensated for when designing wireless communication links in an environment.","PeriodicalId":332500,"journal":{"name":"International Journal of Science for Global Sustainability","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115587701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Magnetohydrodynamic Casson Fluid Flow Past a Vertical Plate in the Presence of Thermal Conductivity and Chemical Absorption 磁流体力学卡森流体在热导和化学吸收作用下流过垂直板

International Journal of Science for Global Sustainability Pub Date : 2020-07-27 DOI: 10.57233/ijsgs.v6i2.111

Omokhuale, E., Jabaka, M. L.

引用次数: 0

Design, Construction and Evaluation of 5A AC-DC Portable Lead Acid Battery Charger with an Inbuilt Automatic Shut OFF 5A型内置自动关断式交直流便携式铅酸蓄电池充电器的设计、制造与评价

International Journal of Science for Global Sustainability Pub Date : 2020-07-27 DOI: 10.57233/ijsgs.v6i2.116

Y. Yahaya, H. Nawawi, Yahya

{"title":"Design, Construction and Evaluation of 5A AC-DC Portable Lead Acid Battery Charger with an Inbuilt Automatic Shut OFF","authors":"Y. Yahaya, H. Nawawi, Yahya","doi":"10.57233/ijsgs.v6i2.116","DOIUrl":"https://doi.org/10.57233/ijsgs.v6i2.116","url":null,"abstract":"Battery charger is a system that restores battery after being discharged. It is well known that battery can be destroyed for being discharged below its manufacturers specified discharge voltage limit, when left for some hours. A single switch fly back buck converter that enables battery charging from the alternating current (AC) supply is designed, and constructed. To prevent the battery from overcharging an automatic charge controller was added to the design. Size of the charger was minimised by designing it to operate at higher frequency. It has an input potential difference (PD) from 80 to 250 volt. The circuit components and other design materials were chosen based on their simplicity and availability in most of the electronics shops. Red light emitting diode (LED) is ON when the charger is connected to the mains supply while the green LED is ON when charging is cut OFF or completed. The design was first conducted on MULTISIM software to ascertain the working conditions of the circuits before the construction procedure. Performance analysis was carried out and found working appropriately.","PeriodicalId":332500,"journal":{"name":"International Journal of Science for Global Sustainability","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130422389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Malaria Prevalence in Gusau Township, Nigeria (A Preliminary Report) 尼日利亚Gusau镇疟疾流行情况(初步报告)

International Journal of Science for Global Sustainability Pub Date : 2020-03-31 DOI: 10.57233/ijsgs.v6i1.135

Abdullahi, K., Shinkafi, S. A., Aguh, B.I., Bilbis, L.S., Danladi, A., Mohammad, B.A., Mafara, M.A., Mohammad, A., Ibrahim, B.

引用次数: 0

International Journal of Science for Global Sustainability (IJSGS): A Bibliometric Analysis: 2015-2019 全球可持续发展科学国际期刊》（IJSGS）：文献计量分析：2015-2019 年

International Journal of Science for Global Sustainability Pub Date : 2020-03-31 DOI: 10.57233/ijsgs.v6i1.120

Gadanga Aliyu Tsafe, C. Chukwuji, Nwabueze

{"title":"International Journal of Science for Global Sustainability (IJSGS): A Bibliometric Analysis: 2015-2019","authors":"Gadanga Aliyu Tsafe, C. Chukwuji, Nwabueze","doi":"10.57233/ijsgs.v6i1.120","DOIUrl":"https://doi.org/10.57233/ijsgs.v6i1.120","url":null,"abstract":"Bibliometric analysis method was used in this study. Observation and physical counting method was adopted to examine the bibliographic characteristics and development of the assembled issues/volumes which were available in the Federal University Gusau (FUGUS) library and confirmed by the past and present Editors-in-Chief of the Journal. The study covered 8 volumes of the IJSGS from the period 2015 to 2019. The bibliometric characteristics examined in this study are (i) Number of issues published per year, (ii) Distribution of articles published per volume, (iii) Authorship pattern (single & multiple), (iv) Authorship affiliation (Universities, Research/special organizations-NAFDAC, Private, MDAs etc, Polytechnics, and Colleges), (v) FUGUS authorship; (vi) Most cited source of information which for convenience sake were divided into six, namely; books (including chapter contributions), journals, proceedings (conferences, workshops, seminars, symposiums and technical/scientific reports), Thesis/Dissertations/Projects, (Internet resources and Others (Bulletin, Newsletter, Guides, newspapers, magazines, maps/atlases, unidentifiable sources etc). (vii) Most cited journal title and ranking of the journal titles. A benchmark of 5 reference listing was set to select a Journal title as most cited/referenced/listed. Findings include the journal’s inconsistency in the number of issues published per year from 2015-2019; FUGUS staff authorship pattern shows that the department of Chemistry contributed more papers to the journal than other departments. It was also revealed that African Journal of Biotechnology was the most cited journal title and as such ranked first. The study recommended that urgent efforts should be made to make the journal more visible by hosting it on the FUGUS website as well getting it indexed.","PeriodicalId":332500,"journal":{"name":"International Journal of Science for Global Sustainability","volume":" 19","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141219854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Heat Absorption Effect on Free Convection Flow Past a Vertical Porous Pipe with Mass Transfer 垂直多孔管传质过程中自由对流的吸热效应

International Journal of Science for Global Sustainability Pub Date : 2020-03-31 DOI: 10.57233/ijsgs.v6i1.136

Altine, M.M., Omokhuale, E., Onwubuya, I. O., Disu, A.B.

{"title":"Heat Absorption Effect on Free Convection Flow Past a Vertical Porous Pipe with Mass Transfer","authors":"Altine, M.M., Omokhuale, E., Onwubuya, I. O., Disu, A.B.","doi":"10.57233/ijsgs.v6i1.136","DOIUrl":"https://doi.org/10.57233/ijsgs.v6i1.136","url":null,"abstract":"This study investigates heat absorption on free convection flow past a vertical porous pipe with mass transfer. The governing equations are the continuity, momentum, energy and diffusion equations. The equations in dimensionless form were transformed into ordinary differential equations (ODEs) and solved analytically using perturbation method. Approximate solutions for the velocity, temperature and concentration were determined. Results are presented graphically showing the effects of various parameters on the fluid flow. It is observed that the velocity becomes higher when thermal Grashof number and sustentions paramètre are increased. Also, increase in magnetic parameter, Schmidt number and Prandtl number lead to fall in the velocity of the fluid. The temperature of the fluid rises also with increase in heat generation but reduces for increased values of Prandtl number. Consequently, the concentration boundary layer decreases with increasing values of Schmidt number. Furthermore, increase in suction/injection has a retarding and accelerating effect on the velocity, temperature and concentration of the fluid respectively.","PeriodicalId":332500,"journal":{"name":"International Journal of Science for Global Sustainability","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125317684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Geophysical Evaluation of Groundwater Potential Using Electrical Resistivity Method in Nigerian Defence Academy, Kaduna, Nigeria 利用电阻率法对尼日利亚卡杜纳国防学院地下水势进行地球物理评价

International Journal of Science for Global Sustainability Pub Date : 2019-12-24 DOI: 10.57233/ijsgs.v5i2.149

Shaibu, I., Udensi, E. E.

{"title":"Geophysical Evaluation of Groundwater Potential Using Electrical Resistivity Method in Nigerian Defence Academy, Kaduna, Nigeria","authors":"Shaibu, I., Udensi, E. E.","doi":"10.57233/ijsgs.v5i2.149","DOIUrl":"https://doi.org/10.57233/ijsgs.v5i2.149","url":null,"abstract":"The groundwater potential of the (NDA, Kaduna) was investigated using vertical electrical sounding (VES) method. A total number of 40 vertical electrical sounding VES points were used for the investigation using Schlumberger array and data obtained were analyzed using curve matching and computer iteration techniques. The data revealed a 3-layer (A, KH and H Curve type) and 4-layer (A and H-curve type). In the 3-layer system, the apparent resistivity of the first layer ranged from 18.9 Ωm to 183.2 Ωm with a corresponding thickness of 0.7 m to 14.8 m. The second layer has apparent resistivity value ranged from 13.5 Ωm to 423.8 Ωm with a corresponding thickness in the range of 4.5 m to 14.7 m while the third layer has resistivity values ranging from 1156.4 Ωm to 3732.7 Ωm with an infinite depth. For the four (4) layered model curves, first layer’s resistivity ranged from 29.5 Ωm to 244.7 Ωm, with a corresponding thickness ranging from 0.8 m to 13.0 m. The resistivity of the second layers ranged between 25.2 Ωm to 183.4 Ωm with a corresponding thickness ranging from 8.0 m to 14.2 m. The third layer resistivity ranged from 119.4 Ωm to 586.7 Ωm with a corresponding thickness ranging from 8.1 m to 20.4 m. The forth layer has a resistivity value ranging from 1318.3 Ωm to 3240.9 Ωm with an infinite depth. An integration of both isopach and iso-resistivity maps for both the 3- layer model curves and 4- layer model curves indicates that most of the northwest parts of the study area have low apparent resistivity values and thick overburden which implies good groundwater potential while, the southern portion has a little higher resistivity values and shallow overburden, an indication of poor groundwater potential. Future boreholes in the area should reached an expected depth of 40 m to 60 m depth","PeriodicalId":332500,"journal":{"name":"International Journal of Science for Global Sustainability","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126734646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Uses of seismic refraction tomography in investigation of groundwater potential in Kaduna millennium city, Kaduna Nigeria 地震折射层析成像在尼日利亚卡杜纳千年城地下水潜力调查中的应用

International Journal of Science for Global Sustainability Pub Date : 2019-09-30 DOI: 10.57233/ijsgs.v5i1.159

Shaibu, I., Udensi, E. E., Usman, D. A.

{"title":"Uses of seismic refraction tomography in investigation of groundwater potential in Kaduna millennium city, Kaduna Nigeria","authors":"Shaibu, I., Udensi, E. E., Usman, D. A.","doi":"10.57233/ijsgs.v5i1.159","DOIUrl":"https://doi.org/10.57233/ijsgs.v5i1.159","url":null,"abstract":"Seismic refraction tomography is unique in the sense that shot are taken at every receiver position along the spread. In that way, it becomes possible to conduct both forward and reverse shooting simultaneously along the profile lines. Therefore, every point within the subsurface along the profile lines is probed by both forward and reversed shots. This leads to what one might call the scanning of the subsurface. The data were processed with ReflexW software and a conventional forwardand reversed travel time curve was plotted for each profile lines. Thereafter joint inversion of the travel time picks was carried out. This resulted in the generation of an iterative model, which was used to generate tomographic sections. The result of seismic refraction tomography showed lateral and vertical variation in velocity along most of the profile lines, thereby giving a true image of velocity distribution, both vertically and laterally within the subsurface. Refraction Tomography gave accurate depth and thickness of the overburden along the profile and to delineate aquifer potentialin the basement topography. The aquifer is estimated to be around 45m to 60m along the entire profile line","PeriodicalId":332500,"journal":{"name":"International Journal of Science for Global Sustainability","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125813151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analysis of Some Brands of Detergent Sold in Sokoto 索科托市部分品牌洗涤剂销售情况分析

International Journal of Science for Global Sustainability Pub Date : 2017-12-28 DOI: 10.57233/ijsgs.v8i3.182

Bello, S., Yusuf, A.J., Mshellia, H. E., Lawwali, H.

引用次数: 0

The Effectiveness of Variable Properties on Thermophoresis Particle Deposition at The Levels of 1st and 4th Orders of Chemical Reaction of Buoyancy-driven Flows of Second Grade Fluid 二级流体浮力驱动流一、四级化学反应中不同性质对热泳动颗粒沉积的影响

International Journal of Science for Global Sustainability Pub Date : 2017-12-28 DOI: 10.57233/ijsgs.v4i2.179

Oreyeni, T., Omokhuale, E., Sa’adu, L.

{"title":"The Effectiveness of Variable Properties on Thermophoresis Particle Deposition at The Levels of 1st and 4th Orders of Chemical Reaction of Buoyancy-driven Flows of Second Grade Fluid","authors":"Oreyeni, T., Omokhuale, E., Sa’adu, L.","doi":"10.57233/ijsgs.v4i2.179","DOIUrl":"https://doi.org/10.57233/ijsgs.v4i2.179","url":null,"abstract":"This article presents the analytic solution to a steady, incompressible, free convective flow of an electrically conducting second grade fluid past a vertical surface with variable properties namely: variable viscosity; variable thermal conductivity and variable concentration diffusivity in the presence of thermophoresis, chemical reaction and convective boundary condition. The impact of different orders of chemical reaction on thermophoresis and the transport process of flow, heat and mass transfer in the boundary layer for assisting and opposing flow cases are properly examined and discussed. The governing equations associated with the fluid model are transformed and parameterized to a system of coupled nonlinear ordinary differential equations using similarity transformations. The resulting coupled ordinary differential equations (ODEs) were solved by adopting the Optimal Homotopy Analysis Method (OHAM). The results indicate that velocity and temperature distributions are decreasing functions of second grade parameter for both cases of assisting and opposing flows. Also, concentration distribution is a decreasing function of thermophoretic parameter for low and high orders of chemical reaction.","PeriodicalId":332500,"journal":{"name":"International Journal of Science for Global Sustainability","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127801390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1