Development of a System Framework that Estimate Cooling Loads for Air-Conditioning System for Residential and Non-residential Buildings

Cooling Load estimation for air conditioning systems is done either by manual calculation or judgmental estimation based on experience of the air conditioning practitioner. While manual calculation is laborious, estimate based on judgment is liable to error due to gigantic, complex and dynamic nature of present day architectural designs. Load calculation through computer automation is likely to make a positive impact in the dynamic nature of air conditioning applications. This study developed computer software to handle simple and typical load estimate for air conditioning in Nigeria. The study has developed a system framework that estimate cooling loads for air-conditioning system for residential and non-residential buildings. It provides an effective and user-friendly way of introducing a residential cooling load calculation program to users. This software results compare favourably with the previous works and it can be used for educational purposes in air conditioning laboratory. Keywords: Air-conditioning, Cooling loads, Residential buildings, Syste

Modelling of Moisture Loss and Oil Uptake During Deep-Fat Frying of Plantain (Dodo)

In this study, model was developed to predict moisture loss and oil uptake during deep-fat frying of plantain (dodo). Plantain samples were sliced and fried at different frying temperatures (150, 160, 170, 180 and 190 °C) in a deep fryer for periods varying from 2 to 4 min. Moisture and fat analyses were determined based on the AOAC standard method. Mathematical model was developed from fundamental law of mass diffusion with the aim of predicting moisture loss and oil uptake rate during DFF of dodo. The model was solved numerically using explicit Finite Difference Technique (FDT). Computer codes were written in MATLAB environment for moisture loss and oil uptake in the slices at different frying conditions. The predicted results were compared with experimental data and good agreement was obtained. The correlation coefficients between the predicted and experimental values of moisture and oil transfer models ranged from 0.988 to 0.994 and 0.958 to 0.978, respectively. The results show that the model is consistent and it may be used to predict moisture loss and oil uptake during deep-fat fried of dodo

Investigation of Some Factors Influencing Corrosion on Refrigerator

The corrosion of steel reinforcing bar can proceed out of sight and eventually result in failure of a section of the highway. The collapse of electrical towers, damage to building, leakages in refrigerator all these result in significant repair cost, endangering public safety and health. This paper presents investigation of some factors influencing corrosion on refrigerator, such as presence of dissolved mineral, organic impurities and dissolved gasses in the water. The survey results are presented using graphs. T-test and Anova were used to ascertain the significance of the factors. The result of alternative Hypothesis and null Hypothesis on the T-test and Anova test were carried out on the factors causing corrosion and responsible for the corrosion were able to be identified. The results revealed that the corrosive effect of fresh water varies from locality to locality due to the wide variety of dissolved impurities, the organism causing the greatest corrosion problems are bacteria and fungi, time of exposure to a corrosive environment influences metal corrosion, most salt solution is good electrolyte and can promote corrosive attack and corrosion effects reduce the life span of refrigerator. The result of this research would guide environmental and material engineers in better planning to minimize corrosion

Comparative Antioxidants Status of Leaves Extracts of Some Common Antimalarial Plants in West Africa

Objective: Malaria chemotherapy remains relevance and gives way to the re-evaluation of medicinal plants that has already gain approval in the traditional treatments of Malaria. This work evaluated and compared the antioxidant status of methanol leaves extracts of Azadirachta Indica (MAI), Vernonia Amygdalina (MVA) and Carica Papaya (MCP). Methods: Phenols, Flavonoids,percentage inhibition of lipid peroxidation and radical scavenging activities using 1,1-diphenyl-2- picryl hydrazyl (DPPH) and Hydroxyl radicals were determined spectrophotometrically based on international standardized methods . Results: Total Phenolic content in garlic acid equivalence (GAE)were expressed maximally at 700μg/ml by 0.015±0.002, 0.019±0.017, 0.013±0.006 mg/g and flavonoids contents at 350μg/ml by 0.063±0.004, 0.020±0.031, 0.049±0.002 Mg/g quercetin equivalence (QE) for MAI, MVA and MCP respectively. DPPH scavenging activities of 78.60, 55.55 and 54.96 % were obtained at 350μg/ml by MAI, MVA and MCP respectively in the order MAI>MVA>MCP. At 300μg/ml, the extracts scavenged hydroxyl radicals significantly( p≤0.05) by72.00, 77.80 and 53.15 % in the order MVA>MAI>MCP. Intriguingly, extracts also convered significantly (p≤0.05), 50% cell protection as they inhibited lipid peroxidation by50.00, 66.20 and 64.30% in the order MVA>MCP>MAI at 350μg/ml, respectively. Conclusion: Antioxidative properties exhibited by extracts may be correlated with their antimalarial functions, bioactive contents and suggestive of MVA as more potent antimalarial of the evaluated plants which may serve as template for malaria drugs and its local usage encouraged in poverty- stricken malarial-endemic areas of West Africa. Keywords: AzadirachtaIndica, Antimalarial, Antioxidants, CaricaPapaya, Malaria, Vernonia Amygdalina

Thermal Evaluation of Some Locally Sourced Activated Carbons from Agricultural Residues

Activated carbons are progressively used as an economical and stable mass separation agent for eliminating surfactants to raise the final product property in many industrial processes. Activated carbon has various applications in different fields, and it performs differently at different temperatures; hence this paper presents a thermal experimental characterization of some locally produced activated carbon from agricultural residues. The experiment was done on the locally produced activated carbon from coconut shell, coconut husk, palm kernel shell, maize husk and imported activated carbons. The adsorbate used is Methylene Blue (MB), the samples were agitated in a water bath shaker at different concentration of adsorbate (50, 100, 150 and 200 ppm) and different temperatures (30 oC, 40 oC, and 50 oC). Adsorption isotherm study is carried out on two well-known isotherms; Langmuir and Freundlich isotherm models. The results revealed that the adsorption capacity of the five samples increased with temperature and initial dye concentration. The adsorption in the samples follows the Langmuir Isotherm model that implies homogenous adsorption and Maize husk has the highest monolayer adsorption capacity at 40 oC. Hence the carbons will perform satisfactorily under heat as the combination of adsorbent and adsorbate in adsorption refrigeration system. The locally produced activated carbons compared favourably with imported activated carbon, hence locally produced activated carbons can replace imported activated, to reduce dependency on foreign product and improve the economy of the country. Keywords: Evaluation, Activated carbon,Adsorption Isotherm, Agricultural Residue

DEVELOPMENT OF EXTENDED SURFACE HEAT TRANSFER EQUIPMENT AS LABORATORIES TEACHING AIDS

  One of the effective ways of enhancing the heat transfer rate between a solid and an adjoining fluid is through the use of an extended surface called fin. Extended surface enhances the heat transfer rate by increasing the area of the surface through which heat is transferred. This paper presents the design, construction and testing of an extended surface heat transfer teaching equipment. Extended heat transfer equipment is made of metal rod of 10 mm diameter and length 350 mm, heater of 60 W capacity, Plaster of Paris (P.O.P) insulator, stands-support for heater, insulator and the metal rod and base flat bed of 500 mm × 200 mm × 80 mm.  Experimental studies were carried out on three materials (brass, mild steel and aluminum) to determine their respective temperature distribution along an extended surface over a length of 28 cm for 2700 seconds interval at different voltage of 50, 100 and 150 volts. The theoretical analysis results were compared with the experimental results and the temperature distribution in the three materials were compared. The results revealed that, Aluminium has the highest temperature value, followed by Brass and Mild Steel at different voltages considered. The temperature increases as voltage increases, at 50, 100 and 150 volts, temperature values are 70, 113 and 157 oC for Aluminum, 65, 111 and 141 oC for Brass and 60, 87 and 100 oC for Mild Steel respectively for 2700 seconds. This explains the reason why Aluminium has the highest heat transfer characteristics followed by Brass and Mild steel. Statistical t-test analysis at 95% confidence limit confirmed that there is no significant difference between the theoretical results and experimental results. Analysis of variance, ANOVA at 95% confidence limit confirmed that, there is significant difference between the temperature gradient of the three selected material. Finally, the extended surface heat transfer equipment is affordable as produced with locally available materials; It has enhance easy maintenance, reliability and accuracy of results. It can be used as teaching aids in laboratories and research institutes

GLOBALIZATION CULTURE AND ARCHITECTURAL EDUCATION IN NIGERIA

Globalization has exerted so much pressure on every aspect of the global economy. This pressure is fast affecting the economy of most underdeveloped and developing world. The precipitation of the World Trade Organization principles, which compelled participating nations to open up their boarders to foreign goods and services, has finally compelled indigenous culture and economy to untold competition and imminent collapse. This paper considers the inherent and apparent effects of globalization culture on architectural education as well as curriculum development in Nigerian Schools of Architecture. It opined that there is a need to marry both the unique tropical Nigerian environment with its cultural background, while embracing the loftiness of foreign design concept and flavour that are initiated through globalization. It asserted that while globalization principles can be embraced, great caution should be exercised. Finally, both environmental harmony as well as sustainability factors must be given due considerations in harnessing any global design concept. This will avert the intractable architectural misdemeanours prevailing in Nigeria communities. Through appropriate architectural education, so much can be achieved in re-orientating the Nigerian architects

Comparative Antioxidants Status of Leaves Extracts of Some Common Antimalarial Plants in West Africa

Objective: Malaria chemotherapy remains relevance and gives way to the re-evaluation of medicinal plants that has already gain approval in the traditional treatments of Malaria. This work evaluated and compared the antioxidant status of methanol leaves extracts of Azadirachta Indica (MAI), Vernonia Amygdalina (MVA) and Carica Papaya (MCP). Methods: Phenols, Flavonoids,percentage inhibition of lipid peroxidation and radical scavenging activities using 1,1-diphenyl-2- picryl hydrazyl (DPPH) and Hydroxyl radicals were determined spectrophotometrically based on international standardized methods . Results: Total Phenolic content in garlic acid equivalence (GAE)were expressed maximally at 700μg/ml by 0.015±0.002, 0.019±0.017, 0.013±0.006 mg/g and flavonoids contents at 350μg/ml by 0.063±0.004, 0.020±0.031, 0.049±0.002 Mg/g quercetin equivalence (QE) for MAI, MVA and MCP respectively. DPPH scavenging activities of 78.60, 55.55 and 54.96 % were obtained at 350μg/ml by MAI, MVA and MCP respectively in the order MAI>MVA>MCP. At 300μg/ml, the extracts scavenged hydroxyl radicals significantly( p≤0.05) by72.00, 77.80 and 53.15 % in the order MVA>MAI>MCP. Intriguingly, extracts also convered significantly (p≤0.05), 50% cell protection as they inhibited lipid peroxidation by50.00, 66.20 and 64.30% in the order MVA>MCP>MAI at 350μg/ml, respectively. Conclusion: Antioxidative properties exhibited by extracts may be correlated with their antimalarial functions, bioactive contents and suggestive of MVA as more potent antimalarial of the evaluated plants which may serve as template for malaria drugs and its local usage encouraged in poverty- stricken malarial-endemic areas of West Africa

DEVELOPMENT OF A MODIFIED CLONAL SELECTION ALGORITHM FOR FEATURE LEVEL FUSION OF MULTIBIOMETRIC SYSTEMS

Feature level fusion is the combination of biometric information contained in the extracted features of biometric images. However, feature-balance maintenance and high computational complexity are one of the major problems encountered when fusion is done at feature level. Therefore, in this paper, a Modified Clonal Selection Algorithm (MCSA) which is characterized by feature-balance maintenance capability and low computational complexity was developed for feature level fusion of multibiometric systems.The standard Tournament Selection Method (TSM) was modified by performing tournaments among neighbours rather than by random selection to reduce the between-group selection pressure associated with the standard TSM. Clonal Selection  algorithm was formulated by incorporating the Modified Tournament Selection Method  (MTSM) into its selection phase. The modified algorithm could be employed for feature level fusion of multibiometric systems

COMPARATIVE ANALYSIS OF TWO BIOMETRIC ACCESS CONTROL SYSTEMS

This paper compared two Biometric Access Control Systems (BACS). The BACSs employed iris pattern for their authentication. Fast Fourier Transform-driven Access Control System (FACS) uses global iris features while Haar Wavelet Transform-driven Access Control System (HACS) uses local iris features for its template generation. Principal Component Analysis (PCA) was employed to select principal components of the extracted features (local and global). Fuzzy clustering was used for classification and Euclidean Distance (ED) as the distance metric. Experimental result showed that it took more time to train the HACS than FACS because of its intrinsic location in the iris images. It was discovered that global features driven Access Control System (FACS) with EER being 7.78 outperformed the local features driven Access Control System (HACS) with EER of 8.05. Though the two systems satisfied the benchmark of 80% for Recognition Accuracy (RA) of Biometric Systems, FACS exhibited RA of 89.87% while HACS achieved a RA of 83.83% when tested on iris images captured with CMITECH DMX-10 Portable USB 5.0 M pixel CCD Iris Camera at automatic convenient eye distances. Performance of global and local features on other biometric recognition systems can be tested and a means of combining the two features for hybridization can also be sought