bluuebunny/crossref_metadata_2025_split huggingface dataset:
A comparative analysis of selected clustering algorithms for criminal profiling
Authors: Adeyiga J.A. , Olabiyisi S.O. , Omidiora E.O. 
Published: September 2020

Several criminal profiling systems have been developed to assist the Law Enforcement Agencies in solving crimes but the techniques employed in most of the systems lack the ability to cluster criminal based on their behavioral characteristics. This paper reviewed different clustering techniques used in criminal profiling and then selects one fuzzy clustering algorithm (Expectation Maximization) and two hard clustering algorithm (K-means and Hierarchical). The selected algorithms were then developed and tested on real life data to produce "profiles" of criminal activity and behavior of criminals. The algorithms were implemented using WEKA software package. The performance of the algorithms was evaluated using cluster accuracy and time complexity. The results show that Expectation Maximization algorithm gave a 90.5% clusters accuracy in 8.5s, while K-Means had 62.6% in 0.09s and Hierarchical with 51.9% in 0.11s. In conclusion, soft clustering algorithm performs better than hard clustering algorithm in analyzing criminal data.
Keywords: Clustering Algorithm, Profiling, Crime, Membership value
Controllable single-phase smart synchronous generator towards solar-pneumatic power generation
Authors: Akinloye B.O. , Uzedhe G.O. 
Published: September 2020

This paper presents the development of a controllable single-phase surface-mounted permanent magnet synchronous generator (SPSMPMSG) for low speed applications. Presently, the world is faced with degrading climatic conditions that may be worsen if energy need is met by fossil fuel and other conventional means of generation. On the other hand, renewable alternatives are not always of constant speed, and are usually not high enough to turn conventional alternators. There is therefore a need for the development of alternators that can generate electricity from low speed sources. The development of permanent magnet from rare-earth materials has revolutionized the electrical generator development. Permanent magnet machines are characterized by high torque, low noise, high efficiency and high power factor. The use of these magnets also made it possible to add computer based controllability making the generator a smart machine. This paper presents a CAD design of smart generator at an input speed of 500rpm to a turbine to produce a constant output of 220V. Simulation and physical test results produce an output of 220V ± 1% and give a clear indication that low speed renewable energy sources can produce usable electrical power.
Keywords: Smart generator, Permanent magnet generator, stator, rotor, Computer-aided design.
Exploring multinomial naïve Bayes for Yorùbá text document classification
Authors: Ayogu I.I. 
Published: September 2020

The recent increase in the emergence of Nigerian language text online motivates this paper in which the problem of classifying text documents written in Yorùbá language into one of a few pre-designated classes is considered. Text document classification/categorization research is well established for English language and many other languages; this is not so for Nigerian languages. This paper evaluated the performance of a multinomial Naive Bayes model learned on a research dataset consisting of 100 samples of text each from business, sporting, entertainment, technology and political domains, separately on unigram, bigram and trigram features obtained using the bag of words representation approach. Results show that the performance of the model over unigram and bigram features is comparable but significantly better than a model learned on trigram features. The results generally indicate a possibility for the practical application of NB algorithm to the classification of text documents written in Yorùbá language.
Keywords: Supervised learning, text classification, Yorùbá language, text mining, BoW Representation
Determination of the failure mechanism of stand alone solar street light
Authors: Anoliefo E. , Oparaku O.U. , Egoigwe S. , Olisa S. 
Published: September 2020

Despite the acclaimed long-term benefits of solar PV systems, most stand-alone solar projects in Nigeria seem to fail within a short duration. In this work, an analysis is carried out to examine the factors that lead to such poor performance of solar projects in Nigeria. A case study of standalone solar street lights (SASSL) in Nsukka geographical region in Nigeria was explored. The field work was carried out from Dec 2016 - January 2018. Data from field indicate that in most cases, premature battery failure due to undercharging was responsible for the collapse of these stand-alone solar systems. Given that the PV module is the sole charge generator in SASSL, the energy yield of the PV modules used in the SASSLs were further investigated. Controlled experiments were carried out to determine the impact of specific environmental and installations conditions on the yield of the PV modules. The results of the experiments led to the development of a model. The weather and installation specific data were then inserted into the model and were used to determine the likely reasons for the premature failure of SASSLs. The results indicated that the within the period under review, the PV modules were capable of providing adequate energy to the battery for only 25% of the time. For another 25% of the time the energy provided were marginal while for 50% of the time the energy provided were grossly inadequate.
Keywords: Failure, Battery, Dust, Solar, mechanism, Street light, Irradiance, PV Module.
Yield, water use and water productivity of drip-irrigated cucumber in response to irrigation depths and intervals in Kaduna, Nigeria
Authors: Zakka E.J. , Onwuegbunam N.E. , Dare A. , Onwuegbunam D.O. , Emeghara U.U. 
Published: September 2020

A study was carried out at the research farm of the Federal College of Forestry Mechanization, Afaka, Kaduna, Nigeria, to determine the effect of irrigation depths and intervals on the yield, crop water use and water productivity of drip-irrigated cucumber (market-more variety) in two irrigation seasons (2016/17 and 2017/18). Irrigation was scheduled using the reference evaporation data obtained from pan evaporation measurements taken within the experimental periods. The results showed a significant difference in both seasonal crop evapotranspiration and yield at 5% level of significance in both seasons. The highest yields (21 t/ha and 20.3 t/ha) were obtained from the treatments with 100 ETo, irrigated daily (T1), while the lowest (15.5 t/ha and 16.5 t/ha) were obtained from the treatments with 60% ETo, irrigated every four days (T9). The highest water productivities were obtained from the treatments with 60% ETo, irrigated daily (T7), while the lowest were obtained from the treatments with 100% ETo, irrigated every four days (T3), implying a better yield effect due to light high frequent irrigation than deep low frequent irrigation. The marginal difference in yield due to the marginal difference in water applied in T1 and T7 is 3.7 t/ha. It is concluded that full irrigation produced higher yield than deficit irrigation but with lower crop water productivity.
Keywords: Cucumber yield, water use, water productivity, irrigation depth, irrigation interval
Improving the capacity and operational efficiency of an on-street parking system using data-based parking management strategies: case study of watt market in Calabar, South-South Nigeria
Authors: Ukam G.S. 
Published: September 2020

Solving parking challenges in a manner that is sustainable would require a shift from using up more scarce land resources in providing supply to meet an unending demand for parking. Parking management is the approach of tackling parking challenges that efficiently utilizes scarce resources to meet demand in a sustainable way. This paper studied an on-street parking system in the central business district with the aim of proffering policies and strategies that can help improve the capacity and operational efficiency of the park. Parking inventory and the license plate method were employed in analyzing the parking characteristics of the park. By introducing a parking duration restriction, more capacity could be accommodated on the current available lots. A 90-minute limit would accommodate at least 106 more vehicles and increase the turnover from 13 to 14 vehicles per lot for the duration of survey, thus improving operational capacity and efficiency. The paper shows that parking management strategies that are effective in making the difference should be employed based on adequate field surveys, observations and analysis.
Keywords: On street parking, parking capacity, parking management, Parking survey, License plate
Performance of metakaolin based geopolymer concrete at elevated temperature
Authors: Gambo S. , Ibrahim K. , Aliyu A. , Ibrahim A.G. , Abdulsalam H. 
Published: September 2020

Due to the carbon dioxide emission arising from the production of cement, alternative concrete that is environmentally friendly such as metakaolin geopolymer concrete have been developed. However, the performance of metakaolin based geopolymer concrete (MKGC) when exposed to aggressive environment particularly elevated temperature has not been investigated. Therefore, this paper assessed the performance of MKGC exposed to elevated temperatures. MKGC cube specimens of grade 25 were produced using a mix ratio of 1:1.58:3.71.After preparing the specimens, they were placed in an electric oven at a temperature of 60oC for 24 hours. Thereafter, the specimens were stored in the laboratory at ambient temperature for 28 days. The specimens were then exposed to elevated temperatures of 200, 400, 600 and 800oC. After exposure to elevated temperatures, the MKGC specimens were subjected to compressive strength, water absorption and abrasion resistance tests. Results show that at 600 and 800oC, the MKGC lost a compressive strength of 59.69% and 71.71% respectively. Higher water absorption and lower abrasion resistance were also observed.
Keywords: Cement, Compressive Strength, Metakaolin Concrete, Elevated Temperature.
Engine performance of blends of palm kernel oil biodiesel under varying speed at constant torque
Authors: Nwakaire J.N. , Obi O.F. , Ohagwu C.J. , Anyadike C.C. , Ugwu I.E. , Ifoh J.U. 
Published: September 2020

This study conducts a comparative evaluation the effect of using palm kernel oil (PKO), pure petroleum diesel and their blends (B5, B10, B20, B30, B40, and B100), on the performance of a four-cylinder CI diesel engine (David Brown 990: 58hp; 2WD), at Farm Power and Machinery Test laboratory Centre (FPMTLC), Department of Agricultural and Bioresources Engineering, University of Nigeria, Nsukka. The objective of the study was to determine the fuel consumption rates, energy expended, brake specific fuel consumption, and brake thermal efficiency, under varying operating speeds (700 – 1900rpm) at constant torque. Each fuel test was conducted using the Heenan-Froude hydraulic dynamometer engine-test-bed; pure petroleum diesel (B0) was used to generate the baseline data. Variables calculated were analyzed, then compared with each other to determine the differences in the engine performance and also to determine the optimum test fuel. The results obtained show that B10 had the overall optimum energy output, fuel consumption rates, and brake specific fuel consumption of 5431.809J, 3.42E-07 m3/s, and 0.16569l/KWh, respectively at the highest engine speed of 1900. B10 had an excellent brake thermal efficiency of 60.6% but was not better than B100, which showed a higher value of 66.95%. From the analysis, B10 is the optimum test fuel and can be used as an alternative fuel in David Brown 990 (58hp; 2WD) or similar CI diesel engines without any engine modification, even though B100 showed potential as an alternative to fossil diesel. Biofuel production grows through integrated aquaculture and algae production; the algae oil will serve as a raw material for biofuel production
Keywords: Blends, Biodiesel, Brake Specific Consumption, Diesel Engine, Fuel Consumption rate, Thermal Efficiency.
COP enhancement of vapour compression refrigeration system using dedicated mechanical subcooling cycle
Authors: Mogaji T.S. , Awolala A. , Ayodeji O.Z. , Mogaji P.B. , Philip D.E. 
Published: September 2020

This study focused on development of an improved vapour compression refrigeration system (IVCR system). Dedicated mechanical subcooling cycle is employed in attaining the developed IVCR system. The system is composed of two cycles cascade refrigeration system working with R134a. It consists of a rectangular shape with total storage space of 0.582 m3, made of galvanized mild steel and internally insulated with 0.05 m polystyrene foam. Tests under a wide range operating temperature conditions were carried out on the developed IVCR system. Performance evaluation of the system was characterized in terms of cooling capacity and coefficient of performance (COP). Experimental results showed that the COP of the subcooled system improved better than that of the main system from 18.0% to about 33.5% over an evaporating temperature range of -10 to 30oC. It can be concluded that the use of dedicated sub cooling cycle in VCR system is more efficient and suitable for the betterment of thermal system performance.
Keywords: Vapour compression Refrigeration system, Coefficient of performance, dedicated subcooled system, Condensation temperature, Evaporation temperature.
Influence of temperature difference (water-cover surface) on the performance of a compact hemispherical solar still
Authors: Adewole B.Z. , Arabambi A.E. , Asere A.A. 
Published: September 2020

The study investigated the influence of temperature difference (ΔT) between evaporative and condensing surface temperature on water productivity of hemispherical solar still. The still was developed, tested and evaluated under the climatic conditions of Ile-Ife, Nigeria, to obtain an average distillate yield per hour per day for different combination of basin temperature, water temperature, transparent cover temperature, ambient temperature and solar intensity. Results indicated a decrease in the hourly water yield as (ΔT) increases. Regression analysis revealed that ΔT has no significant influence on the hourly water yield (P > 0.05). Maximum water productivity was obtained for a low condensing surface temperature and a high evaporative surface temperature. The study concluded that the improvement on water productivity of solar still can be achieved by enhancing the evaporative and condensing surface temperature. Methods for obtaining higher evaporating temperature should be sought in order to boost water productivity of solar stills.
Keywords: Temperature difference, Evaporative surface, Condensing surface, Hourly water yield, Heat losses.
Analysis and implementation of a solar tracking rack system
Authors: Okandeji A.A. , Olajide M.B. , Olasunkanmi G.O. , Jagun Z.O. 
Published: September 2020

Solar energy is the most feasible source of renewable energy especially in sun rich regions like Africa. In particular, electrically epileptic country like Nigeria with current power output of only about 3.5GW of energy has a relatively long sunny period for about 90% of the year, making Nigeria very rich in solar power. Maximally harnessing solar energy into usable electricity however, is still a fundamental problem as the existing models can harness only about 70% of the available energy. To maximally harness solar energy, a solar panel must be perpendicular to the energy source for all 12hours of sunlight availability, and must be able to follow the sun’s movement all day long. Accordingly, this work considers the analysis, construction, and implementation of a single axis solar tracking dynamic system. Experimental result show that the proposed system outperforms the conventional static solar tracking system.
Keywords: solar energy, single axis, harvesting-solar energy.
Application of 2-dimensional tomography to investigate subsurface lithology in Auchi polytechnic, auchi, Edo state, nigeria
Authors: Aigbogun C.O. , Babaiwa D.A. , Mujakperuo B.J.O. 
Published: September 2020

The Wenner – Schlumberger array was used for Constant Separation Traversing (CST) to investigate subsurface lithology in Auchi Polytechnic, Auchi. All the traverses were carried out with electrode spacing of 5 m with a spread of 200 m. The data was obtained using Pasi terrameter (16-GL) and processed with the Dipro software. The subsurface resistivity values ranged from 207 Ωm – 8357 Ωm. The results obtained from this survey classified the subsurface lithology into topsoil, clayey sand, sandy clay and sand. The maximum depth penetrated was 50 m.
Keywords: Lithology, resistivity, subsurface, Wenner-Schlumberger, 2-Dimensional.
Effects of microwave power and slice thickness on fiber and ash contents of dried sweet potato (<i>Ipomoea batata</i>)
Authors: Nwajinka C.O. , Okonjo E.O. , Amaefule D.O. , Okpala D.C. 
Published: September 2020

Investigation of microwave drying of sweet potato slices was conducted at microwave oven power settings of 90, 100, 120 Watts and slice thicknesses of 3mm, 4mm and 6mm using Fourier models and response surface methods. The slice samples dried from initial moisture content of 70.71𝒈𝒘𝒂𝒕𝒆𝒓/𝒈𝒅𝒓𝒚 𝒎𝒂𝒕𝒕𝒆𝒓 to 12.7𝒈𝒘𝒂𝒕𝒆𝒓/𝒈𝒅𝒓𝒚 𝒎𝒂𝒕𝒕𝒆𝒓 final (equilibrium) moisture content in the microwave oven. Fourier models adequately fitted the drying data with the following values of the fit parameters: MBE= 0.00002943 to 0.000645, R² = 0.9987 to 1, RMSE = 0.00384 to 0.01692. Effective moisture diffusion coefficient (𝑫𝒆) of the samples ranged from 𝟏.𝟎𝟖𝟐𝟐 × 𝟏𝟎−𝟑m2/s to 𝟖.𝟑𝟖𝟏𝟐 × 𝟏𝟎−𝟑 m2/s. Analysis of Variance (ANOVA) was used to analyze the effect of drying conditions on the samples parameters at 95% ( p<0.05). The results showed that slice thickness and microwave power have significant effects on the ash and fiber contents of the dried potato samples. At the microwave power of 90 W and slice thickness of 4 mm the values of Fiber and Ash retained in the dried sweet potato samples were optimal at 4.30% and 2.50% respectively, after drying for 390 minutes to an average moisture content of 14.2 gH2O/gdm. Optimized equations for predicting the percent ash and fiber contents at combined factors of microwave power and slice thickness were developed using Response Surface Methodology (RSM) at 95% confidence bound. The coefficients of determination (R2) for the models are 0.7333 and 0.9655 for fiber and ash respectively. These are indications that the models can be used to predict the two food components of microwave dried potato slices.
Keywords: RSM, Fourier Model, Microwave, Sweet Potato, Ash, Fiber
Rare earth elements and stable sulphur (δ34s) isotope of baryte mineralization in Liji Area, Northern Benue trough, northeastern Nigeria
Authors: Kamale H.I. , El-Nafaty J.M. , Umaru A.O. , Shettima B. , Obidiegwu M.U. 
Published: September 2020

The Liji area lithologically consists of inliers of granite and pegmatite members of the Pan-African granitoids surrounded by Cretaceous sedimentary deposits of Bima, Yolde, Pindiga and Gombe Formations. Epigenetic fracture-filling baryte mineralization hosted by granite, pegmatite and Bima Sandstone were delineated, sampled and analyzed for rare-earth elements (REEs) and stable sulphur isotope geochemistry. The REEs of the distal (unaltered) rocks indicated normal values (26.15-36.81 ppm) before mineralization was marked by enrichment of light rare-earth elements (LREEs) (27.94 ppm) relative to the heavy rare-earth elements (HREEs) (5.34 ppm) and negative Eu anomalies typical of calc-alkaline granites of Pan-African age. The baryte separates were marked by enriched LREEs and depleted HREEs with pronounced positive Eu anomalies indicating the invasion and consequent deposition of baryte-rich hydrothermal fluid under oxidizing conditions in the N-S and E-W striking fractures. Stable sulphur isotope of the baryte gives values that ranged from 18.3 - 19.8o/oo CDT indicating that the source of sulphur is from ocean water and not from magmatic, fresh water and connate water sources from the nearby granite, pegmatite and sandstone.
Keywords: Baryte, Mineralization, Hydrothermal, Liji, REE, Sulphur-Isotope.
Análisis de la flagrancia en el delito de chantaje previsto en el Código Penal del Estado de Sonora
Authors: Medina Wahnnatah Armando , Almada Quintero María Guadalupe , Romero Gómez Ángel Antonio , Medina Almada Ana Lucia 
Published: September 2020

En el presente ana?lisis, se exponen consideraciones en relacio?n con los elementos del ili?cito de chantaje, partiendo de los principios primordiales del marco teo?rico respecto al debido proceso, tenemos la seguridad juri?dica y la legalidad, las cuales se sustentan en los arti?culos 14, 16, 19 y 20 de la constitucio?n poli?tica mexicana.
Se aborda tambie?n en este estudio, elementos importantes de los derechos humanos, se estudia en materia penal su fundamento y argumento, al referirnos al co?digo penal para el Estado de Sonora, en su arti?culo 5, advierte que los delitos atendiendo a su momento de consumacio?n, pude ser instanta?neo, cuando la consumacio?n se agota en el mismo momento en que se han realizado todos sus elementos constitutivos; permanente o continuo, cuando la ejecucio?n se prolonga en el tiempo; y continuado, cuando con unidad de propo?sito delictivo y pluralidad de conductas se viola el mismo precepto legal .

Se aborda en el estudio del TIPO PENAL, de CHANTAJE, los elementos que lo constituyen y el momento en que se ejecuta, por u?ltimo se emiten consideraciones finales.
Especificación de un modelo para el estudio de la percepción de seguridad
Authors: Coronado Rincón Oscar , Mejía Rubio Silvia , Quezada Castro Abigail , Blannes Ugarte Adriana Vanessa , Bolivar Mojica Eyder , García Lirios Cruz 
Published: September 2020

La seguridad ha preocupado a las autoridades y a la sociedad civil durante los últimos años. Los diferentes sustratos de la sociedad tienen diferentes percepciones sobre la seguridad. El presente documento explora la confiabilidad y validez de un instrumento que mide la percepción de seguridad en los estudiantes de licenciatura al revisar siete dimensiones: territorial, nacional, público (gobierno), humano, público (autoprotección), privado e internacional. En consecuencia, establecer valores y residuos permitieron aceptar la hipótesis nula relación significativa entre las dimensiones teóricas con respecto a los factores ponderados.
Bases teóricas en la administración de los recursos humanos
Authors: Hernández Govea Luis Manuel , Martínez Prats Germán , Xiconténcatl Valencia Martha Libny 
Published: September 2020

Las organizaciones tienen características muy diferentes de cómo operar dentro del ámbitolaboral, cómo seguir creciendo día con día y uno de los principales pilares es el factor humanoen el que tienen una fortaleza muy importante para el éxito. La competencia entre lasorganizaciones y particularmentelos avances tecnológicos han provocado cambios muyimportantes, que se ven incluso en la forma de administrar las empresas, lo que ha empujado aestas últimas a tener asesores en su plantilla laboral que les ayuden en el área del comportamientohumano de su personal. La cultura de una organización incorpora sus valores, creencias yactitudes, y es la fuerza impulsora de esta conducta.Este artículo expone aquellas posturas teóricas que permitan comprender el quehacer de laadministración de los recursos humanos y su relación coyuntural con el clima organizacionalpara el buen manejo. Ofrece al administrador y al directivo organizacional una comprensión de la dinámica humana del trabajo y de la productividad de las personas, distinta de la visión queofrecen los modelos prescriptivos gerencial eso las tradiciones empresariales y, por tanto, másajustada al saber científico desarrollado en el contexto cultural del propio país y región.