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Global Journal of Pure and Applied Sciences

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Volume 9, No 1 September 2002
Abstracts

EFFECT OF PARTIAL WATER DEPRIVATION ON THE PERFORMANCE AND CARCASS CHARACTERISTICS OF BROLER CHICKENS EXPOSED TO SELECTED DURATIONS OF WATER DEPRIVATION IN THE HUMID TROPICAL ENVIRONMENT

1 Samuel A. Offiong, 2 Francis S. Akpan and  3 Olusegun O. Ojebiyi

1, 2 Department of animal science, faculty of Agriculture, University of Uyo

3 Foundation for Economic research and Training (FERT), Uyo

ABSTRACT

A study was conducted to assess the effects of partial water deprivation on the biologic performance and carcass qualities of broiler chickens raised in a humid tropical environment.  There were 2 experiments involving the use of 280 and 500 broiler chickens of mixed sexes respectively.  These birds were raised to 4 weeks of age and then subjected to selected durations of water deprivation treatments which lasted for 2 and 5 weeks respectively.  Water deprivation exposure had no significant effect (P>0.05) on body weight, weight gain, feed intake, feed conversion ratio and mortality following 2 weeks of treatment in the first experiment.  However, in the second experiment, when the birds were exposed to longer period of water deprivation (5 weeks), body weight and water consumption were significantly affected (P<0.05) by treatments.  But weight gain, feed intake, EFU, water/feed ratio and efficiency of water utilization were not affected.  Depriving birds of water for 6 and 8 hours daily did not adversely depress dressing percentages.   Weights of some body parts were affected by the partial water deprivation treatments.  Organ weights (liver, gizzard, heart and spleen) were generally depressed by water deprivation.  Treatments did not seem to affect the chemical composition of the meat. However the dry matter and moisture contents of the meat tended to vary inversely as the intensity of water deprivation increased.

Keywords:  Partial water deprivation; broiler chickens; performance; carcass; characteristics.

 

AN ANALYSIS OF BEEF DEMAND IN A NIGERIAN URBAN CITY.

Dr. E.J. Udoh1 and Dr. J.O.Akintola2

 1. Department of Agricultural Economics/Extension, University of Uyo, Uyo.

 2.  Department of Agricultural Economics, University of Ibadan, Ibadan

ABSTRACT

The level of beef demand and consumption in Nigerian cities has been questionably and progressively low. This study empirically modeled a demand function of beef meat in Lagos city with the aim of identifying major demand shifters. Based on the regression analysis, unit retail price of beef and disposable income were found to have significant and direct influences on the quantity of beef demanded. Further, trend and policy shift variables represented as SAP dummy were found to have significant but inverse effect on quantity of beef demanded. The study further showed that the quantity of beef (in number and meat equivalent) slaughtered has been on the decline and as such, the per caput beef consumption has become considerably lower over the years, when compared with the minimum value recommended for Nigeria by FAO. The future demand of beef is however estimated to be high. To meet this demand there is the need for both farmers and government to increase production levels of cattle by removing the bottlenecks in livestock husbandry.

Keywords: Beef, demand function, demand projection, animal protein, urban city.

 

 

FUNGI ASSOCIATED WITH PEELS OF  POST HARVEST YAMS (DIOSCOREA SPP.) IN STORAGE

Ralph  N.  OKIGBO

Department of Biological Sciences, Michael Okpara  University of Agriculture, Umudike P.M.B 7267, Umuahia, Abia State, Nigeria.

ABSTRACT

Fungi on surface  of three cultivars of white yam (Dioscorea rotundata Poir) and a cultivar of water yam (D. alata L.) were investigated. The objective of the  study is to show vertical distribution (Head, middle and tail regions) of mycoflora of yam surface. The mycoflora consisted principally of Aspergillus niger Van Tiegh, Botryodiplodia theobromae Pat, Trichoderma sp., Rhizopus sp., Fusarium solani (Mart) Sacc, Choanephora cucurbitarum (Berk and Fav.) Thaxt, Mucor sp. and Penicillium oxalicum Currie and Thom in that order of their frequency of occurrence.  The head region showed significant difference in occurrence of fungi (p < 05) more than the middle and tail regions. The frequency of occurrence of A. niger and B. theobromae was considerable in all the cultivars except in water yam where the occurrence of A. niger was relatively sparse. The implication of tuber surface mycoflora on the post harvest storage of yams is discussed.

Key words:  yam, Peel, tuber surface, mycoflora   

 

PARASITIC CONTAMINATION OF LEAFY VEGETABLES: A FUNCTION OF THE LEAF AREA INDEX (LAI)

*(1) OPARA, KENNETH NNAMDI AND (2)UDOIDUNG, NSIMA I.

DEPARTMENT OF ZOOLOGY UNIVERSITY OF UYO

ABSTRACT

A survey was undertaken to determine the degree of contamination of some stable vegetables and their surrounding soils by parasites in Uyo, Nigeria.  Out of the 780 leaves from six vegetables and 50 soil samples screened, 498 (63.9%) of vegetables and 36 (72%) of the soil samples were positive for parasite ova, larvae or cyst respectively.  The prevalence of the parasites encountered from the vegetables and soil samples were Ascaris lumbricoides (76.3% vs 100%) Hookworm (63.9% vs 66.7%), Trichuris trichiura (53.8% vs 58.3%).  Strongyloides stercoralis (14.1% vs 19.44%), Gardia lamblia (5.6% vs 25.0%), Entamoeba histolytica (2.0%).   The results obtained indicate that Leaf Area Index (LAI) is a contributory factor to high prevalence of contamination irrespective of exposed surface area, the vegetables with smaller leaf are index value are more contaminated than vegetables with higher LAI value.

Keywords:   Vegetables, Parasites, Soil, Contamination.

 

A COMPARATIVE STUDY OF SUPEROXIDE DISMUTASE ACTIVITY OF DIFFERENT YAM SPECIES

  F.  I.  ACHUBA

Department of Biochemistry

Delta State University, P.M.B. 1.  ABRAKA, NIGERIA.

ABSTRACT

The activity of superoxide dismutase (SOD) in three species of yam: Dioscorea cayenensis poir cv okpai, Dioscorea alata poir cv Chembeli  and Dioscorea alata poir cv Kurudu was studied. The study demonstrated a significant variation of superoxide dismutase activity in the three varieties of Dioscorea species. The highest activity was found in Dioscorea cayenensis and the lowest one in Dioscorea alata poir cv Kurudu. The order of activity of the enzyme in the tuber was head > middle > tail physiological region. Inhibition studies with cyanide showed that the enzyme in the yam cell of all the varieties was inhibited by cyanide. These observations indicated that identical SODs are present in the cytosol and mitochondria of the yam cells of the different varieties studied.Thus different  yam species vcxz\have different SOD activities that confer peculiar  protective role against  superoxide `’  anion.

Keywords: Dioscorea alata, Dioscorea cayenensis, superoxide dismutase.

 

ANTIDIABETIC EFFECT OF CRUDE GLYCOSIDE OF ABRUS PRECATORIUS IN ALLOXAN DIABETIC RABBITS

1MONAGO, C.C. AND 2AKHIDUE, V.

1. DEPARTMENT OF BIOCHEMISTRY, UNIVERSITY OF PORT HARCOURT, NIGERIA

2. DEPARTMENT OF PHARMACOLOGY, UNIVERSITY OF PORT HARCOURT, RIVERS STATE NIGERIA

ABSTRACTS

The antidiabetic effect of crude a glycoside from Abrus precatorius seed was studied in alloxan diabetic rabbits.  Three groups of male alloxan diabetic rabbits were used. The three groups (n = 3) received oral injection of 50mg/kg body of crude glycoside (CG), chlorpropamide (CP)-a known synthetic antidiabetic drug and 5mls of normal saline for CG, CP and CO respectively. Blood glucose levels were reduced in CG and CP groups of diabetic rabbits but not in CO. The percentage reduction of blood glucose for CG after 5,10,20,30,40,60, and 168 hours of oral injection were 34.1, 43.4,71.8,73.2,70.6,63.7 and 62.9% respectively while for CP we have 13.8,32.3,61.3,33.5,46.3 and 46.2% respectively. The peak reduction for CG was 73.2% after 30 hours and 61.3% for CP after 20 hrs of oral injection. Both CG and CP did not return back to hyperglycaemic level of 207.60 ± 0.21- 247.20 ± 0.50.

There is a high significant difference between the blood glucose reduction pattern of CG and CP with that of CO at P < 0.001. There is no significant difference in the blood glucose reduction patterns of CG and CP (P < 0.001). 

Key words: Diabetes mellitus, Legumes, Abrus precatorius, Sulfonylurea, Crude glycoside.

 

Anti malarial drug quinine and activated charcoal effect on hAematological parameters in rats.

Nwafor .A.

Department of Human Physiology, Faculty of Basic Medical Sciences,

College of Health Sciences, University of Port Harcourt, P.M.B 5323 Port Harcourt.

ABSTRACTS

The efficacy of oral administration of activated charcoal in ameliorating the harmful effect of quinine on haematological parameters- packed cell volume (PCV), haemoglobin concentration (Hb) and erythrocyte count (Rbc) in animal model was studied. Quinine alone (P <0.05) or activated charcoal alone (P < 0.01) significantly reduced the parameters studied compared with control. Although there was no significant   difference in the values of the parameters studied when activated charcoal was administered 10 minutes before or after oral ingestion of quinine hitherto the reduction in the values of PCV,Hb and Rbc were similar to that obtained with activated charcoal alone; which suggests that oral    administration of activated charcoal as early as possible may have a beneficial effect  in reducing the toxicological effects of quinine on blood parameters  

Key words: Blood picture; charcoal-therapeutic-use; quinine, animal.

 

BIOCHEMICAL CHANGES IN SERUM OF PROTEIN ENERGY MALNOURISHED CHILDREN FOLLOWING DIETARY PROTEIN REPLETION

*USORO, C. A. O; UDOH, A. E; NTUI, I.

Department of Chemical Pathology, College of Medicine, University of Calabar.

ABSTRACT

The serum levels of total protein, albumin, urea, calcium (Ca2+), sodium (Na+), potassium (K+) where determined during a ten day process of dietary protein repletion in 30 protein energy malnourished (PEM) children and in a control group of thirty healthy children of equivalent age group. The findings show that the total protein, albumin, urea, Ca2+, Na+, and K+ were significantly lower (p<0.05) in PEM patients when compared with healthy controls. These parameters were significantly increased (p<0.05) following the ten-day dietary protein repletion. However, the treated group still had significantly lower values (p<0.05) than the healthy controls. The serum levels of total protein, albumin, urea, Ca2+, Na+, K+, were 45.10 ± 2.70g/L; 28.40 ± 2.10g/L; 1.40 ± 0.39mmol/L; 1.30 ± 0.27mmol/L; 128.00 ± 4.30mmol/L; 2.90 ± 0.60mmol/L respectively in the PEM patients and 5.90 ± 2.90g/L: 33.10 ± 2.3g/L; 2.40 ± 0.49mmol/L; 1.90 ± 0.32mmol/L; 131.00 ± 3.30mmol/L and 3.40 ± 0.30mmol/L respectively following a ten day dietary protein repletion. In the healthy controls the values were 66.00 ± 2.20g/L (total protein); 45.54 ± 2.20g/L (albumin); 3.90 ± 0.40mmol/L (urea); 2.40 ± 0.04mmol/L (Ca2+); 140.00 ± 3.30mmol/L (Na+); 4.80 ± 0.70mmol/L (K+). It is concluded that protein repletion normalizes the biochemical parameters listed above.

*Author for correspondence.

Key words: Malnourished children, Protein repletion.

FUNCTIONAL PROPERTIES OF SOYBEAN AND LOCUSTBEAN DAWADAWA; A BACTERIAL FERMENTED PRODUCT

  C. A. Emmanuel Ikpeme, A. O. Oguatunde, C.O. Aworh

Department of Biochemistry University of Calabar

Food Technology Department University of lbadan

ABSTRACT

Functional properties of soybean and locustbean dawadawa; a bacterial fermented product, were investigated. Locustbean and soybean seeds were processed and fermented for 48h and the products; dawadawa, assayed for gelation capacity, water and oil absorption capacity; emulsion capacity and emulsion stability. Results showed that water absorption capacity  (WAC) of fermented soybean increased significantly (P<0.05), while fermentation decreased the WAC of locustbean. Also, there was a significant reduction in the oil retention capacity of fermented products. 

Fermentation caused a considerable reduction in the emulsification capacity of soybean dawadawa. Locustbean dawadawa had least geleation concentration at 30% (W/V). Dawadawa though a seasoning could be used in food systemes where some modification in the functionality of the inherent basic ingredient is required, as in some Nigeria soups.

Key Words: Soybean, locustbean, fermentation, functional properties, dawadawa.

 

AMYLOLYTIC STUDIES OF PLEUROTUS TUBER-REGIUM

1MONAGO, C.C. AND 2OKONKWO J. E.

1. DEPARTMENT OF BIOCHEMISTRY, UNIVERSITY OF PORT HARCOURT, NIGERIA

2. DEPARTMENT OF BIOCHEMISTRY, NNAMDI AZIKIWE UNIVERSITY AWKA, ANAMBRA STATE, NIGERIA

ABSTRACT

The alpha amylase of the sclerotium of Pleurotus tuber-regium was studied.  The enzyme was purified from the fresh sclerotium through dialysis, ammonium sulphate fractionation and column chromatography of CM sephadex. The enzyme showed 70% of it’s optimal activity between p.H 4.0 to 8.0.  Acid and thermal stability was found at p.H 2.0 and temperature of 600c respectively.  Michealis Menton constant (km) and maximum velocity (Vmax) of the enzyme with starch as substrate was 1.25mg/ml and 5.0ug/ml/min, respectively.  The paper chromatography of the hydrolytic products in starch showed hydrolytic products like glucose, maltose and dextrin, suggesting an alpha-amylase type of activity.  Maltose is not hydrolysed by this enzyme.

Keywords: Pleurotus tuber-regium, Amylase, Sclerotium, fungus.


THE EFFECT OF EXPOSURE TO PETROLEUM PRODUCTS ON SOME RENAL FUNCTION PARAMETERS OF MOTOR MECHANICS IN PORT HARCOURT METROPOLIS OF NIGERIA.

*E. S. BARTIMAEUS and M. J. JACOBS

Department of Medical Laboratory Sciences, Rivers  State University of Science and Technology, Port Harcourt, Nigeria

*Corresponding  author.

ABSTRACT

The effect of petroleum products on some renal function parameters was assessed in motor mechanics in Port Harcourt, Nigeria using urinalysis, urea and creatinine estimations.  Traces of protein in urine were found in the exposed population, which increased as the duration of exposure increased.  Mean urea and creatinine levels showed a significant difference (p<0.05) between the exposed and non exposed subjects.  Specific gravity levels of test subjects were low compared to normal.  Tukey test analysis shows a significant difference in urea level between groups of the exposed population but those of creatinine and specific gravity had no inter group difference. A direct relationship therefore was observed between the levels of urea, creatinine, specific gravity, urinary protein and the duration of exposure to these products

Keywords: Petroleum product, creatinine, urea, specific gravity, protein.

 

ANALYSIS OF LOCAL  SALTS USING X-RAY SPECTROMETRIC TECHNIQUES

I.M.Umar

Centre for Energy Research and Training

Ahmadu Bello University, Zaria, Nigeria

ABSTRACT:

Local  salts namely: Mangul, Kantu and Manda have been analysed using x-ray diffraction and x-ray fluorescence techniques. X-ray diffraction has shown that Mangul and Kantu consist of mainly sodium chloride while Manda consists of mainly calcium potassium silicate. The major elements determined using x-ray fluorescence are: Si, P, S, Cl, K, Ca, Ti and Fe, while the trace elements included V, Co, Ni, Cu, Zn, Br,  Rb, Sr, Y and Zr. The Mangul samples were found to contain higher concentrations of Br while Manda had higher Fe concentrations. Toxic elements such as As, Pb, Sb, and Hg are non detectable, which may suggest that the salts may be safe as common salt subsititudes.

Key Words: Mineral metal Salts, Carbonates, Chlorides, Sulphates, Silicates.

 

MACRONUTRIENT STATUS AND SPECIATION OF Cu, Fe, Zn AND Pb IN SOIL CONTAINING PALM OIL MILL EFFLUENT

*P.O. Oviasogie and A.E. Aghimien

Chemistry Division, Nigerian Institute For Oil Palm Research, P.M.B. 1030, Benin City, Nigeria.  

ABSTRACT

The use and safe disposal of Palm Oil Mill Effluent (POME) will no doubt contribute to environmental sustainability. Hence, the macronutreint and forms (speciation) of Copper, Iron, Zinc and Lead status of soil containing POME were determined in this study. The concentrations were determined at 0-15cm and 15-30cm soil depths respectively and at 10m interval from the point of discharge of the POME. Soils at 100m away from the discharge point were regarded as normal or uncontaminated soils, while different extractants were used to determine the levels of Fe, Cu, Zn and Pb. The results showed enrichment of the soils in P, N, Ca, Mg, Na, K due to the application of the POME. Copper, Iron and Pb were predominant in the organic form, while Zinc was particularly present in the exchangeable form. There was an overall increase in the cation exchange capacity (CEC) of the soils especially at the area close to the source of the POME. Proper use and safe disposal of POME in the land environment will lead to improved soil fertility.

Key Words:  macronutreint, speciation, Cation Exchange Capacity, soil fertility, sustainability.

 

The Infrared Spectra of Diaqua Tetra-m - Formato Dichromium (II): A Normal Coordinate Treatment on 1:1 Formate Complex

A. Uzairu, G. F. S. Harrison and A. Adamu

Department of Chemistry,

Ahmadu Bello University, Zaria.

ABSTRACT

The infrared spectrum of diaqua tetra- m - formato dichromium (II) complex has been obtained in the frequency range 4000 to 400cm-1. A normal coordinate treatment performed on the 1:1 model of the complex gives calculated frequencies in good agreement with the observed ones. In order to assign bands and to see the coupling between various vibrational modes, the potential energy distribution in each normal vibration was calculated with respect to each symmetry coordinate for all the in-plane vibrations. The results show that in spite of the effect of coordination some of the formate ligand based vibrational modes remain localized, though others such as nas(COO) and ds(HCO) couple strongly with ring deformation. The analysis also indicate that bands at 464, 537 and 540 cm-1 are assignable to ns (CrOO) coupled with ring deformation, Cr-Cr mode coupled with ds (Cr-Cr-O) bending and nas (CrOO) coupled with das (C-O-Cr) bending, respectively. 

Keywords: Infrared spectrum, normal coordinate treatment, in-plane fundamental vibrations, tetra- m          formato dichromium (II) complex, 1:1 (Cr24+: HCOO-) complex model

 

 

STUDY OF METHYL BROMIDE REACTIVITY WITH HUMAN AND MOUSE HEMOGLOBIN

Bamgbose, J.T1 and Bamgbose, O2

University of Agriculture, P M B 2240, Abeokuta, NIGERIA

1Department of Chemistry

2Department of Environmental Management and Toxicology

1To whom all correspondence should be addressed.

ABSTRACT

  A study has been carried out on in-vitro reactivity of human and mouse hemoglobin spectrophotometrically at physiological pH, using different protein to reagent ratios.  Hemoglobin side chains were modified with different concentrations of methyl bromide on agro-soil fumigant.  To ascertain if the site of alkylation was the reactive sulfhydryl group present at cystein – 93 on the b chain of hemoglobin (b-93 cys), a spectrophotometric measurement using 5,5-dithiobis(2-nitrobenzoic acid) (DTNB) was used to measure the free sulfhydryl groups before and after treatment of hemoglobin with various amounts of methyl bromide.  The results show that the methylbromide reacted substantially with both human and mouse hemoglobin at b-93 cys.

The decrease in the number of sulfhydryl groups (SH) per hemoglobin molecule on addition of various concentrations of methylbromide ranges from 5.10 to 2.35 + 0.01 and 5.01 to 0.93 + 0.01 for human and mouse hemoglobin, respectively.

The results showed a dose-dependent decrease in the number of sulfhydryl group indicating that hemoglobin can serve as a biomarker of human occupational exposure to methy bromide fumigants.

Keywords:  Hemoglobin, sulfhydryl groups, methylbromide, Cysteine, histidine.

 

 

Identification of Trimer and Dimer of 4-hydroxy-3-methoxy benzaldehyde in crystal structure of Vanillin

 

Narayan T. Akinchan

Department of Pure and Applied Chemistry,

University of Calabar, Calabar. Nigeria.

E-mail <akinchan @ unical anpa, net. ng>

ABSTRACT

The effect of intermolecular hydrogen bonding on the molecular structure of vanillin has been studied using negative ion chemical ionization (NICl) mass spectrometry methods.  The [Trimer-H2O] and [Dimer-H2O] were observed at m/z 438 and 286 respectively in NICl (CH4) mass spectrum of vanillin.  The NICl (Cl) mass spectrum of vanillin differs where deprotonated molecular ion peak,  [monomer-H] at m/z,151 was the second most abundant ion peak.  The base ion peak was observed at             m/z,187 due to the presence of monomer+35Cl. The [Trimer-H2O] and [Dimer - H2O] were not detected due to the presence of chloride ion.  The results obtained support that the crystal of vanillin consists of trimer and dimer of 4-hydroxy-3-methoxy benzaldehyde.

 

Keywords   4-hydroxy-3-methoxy benzaldehyde, vanillin, intermolecular hydrogen bonding,

 

Kinetics and mechanism of the oxidation of thiocyanate ion by di-m-oxo-tetrakis(1,10-phenanthroline)-dimanganese (III,IV) ion in acid medium

Y. N. Lohdip and J. F. Iyun

*Department of Chemistry, University of Jos, Nigeria

**Department of Chemistry, Ahmadu Bello University, Zaria, Nigeria

ABSTRACT

The kinetics of oxidation of thiocyanate ion by di-m-oxo-tetrakis(1,10-phenanthroline)dimanganese(III,IV) perchlorate in acid medium has been investigated. The reaction follows first order in both the oxidant and the reductant. The reaction is catalysed by hydrogen ion and the rate dependence given as k2  =  a +  b[H+].  The reaction rate is not affected by changes in the ionic strength and dielectric constant of the reaction medium. The reaction did not induce polymerization of acrylamide and the presence of NO3- or HCOO- had no effect on the rate. A plausible mechanism involving proton coupled electron transfer (PCET) is proposed.

Key words: Kinetics, mechanism, oxidation, thiocyanate, di-m-oxo-tetrakis(1,10-phenanthroline)-dimanganese (III,IV)

 

DESIGN, CONSTRUCTION AND TESTING OF A LOW-COST FLAT PLATE SOLAR ENERGY COLLECTOR

BY

Asiegbu Anyalewechi .D.
Department of Mathematical & Physical Sciences

Michael Okpara 
University of Agriculture, Umudike

ABSTRACT

A low-cost flat plate solar energy collector has been designed and constructed with locally available materials such as mild steel and black paint of absorptance 0.94. On testing, an average daily efficiency of 55.6% was obtained. The methods are simple and illustrate the fact that construction of efficient collectors are possible and achievable by our local users on a do- it – yourself basis. The fact that this will minimize cost and over dependence on electricity for minor heating processes at homes, schools and hospitals in relation to developing countries were discussed.

Key Words: Low-cost, solar-energy-collector, Local-Materials, efficiency, construction.

 

X-RAY ABSORPTION BY SODIUM CHLORIDE

N. O. Egbe, * B. Olisemeke, S. O. Inyang, A. F. Nneoyi-Egbe and G. B. Inah

N. O. Egbe          
Department of Radiography, University of Calabar, Nigeria

B.     Olisemeke
Department of Radiography, University of Calabar, Nigeria

S.  O. Inyang 
Department of Physics, University of Calabar, Nigeria

A. F. Nneoyi-Egbe          
Department of Chemistry, University of Calabar, Nigeria

G . B. Inah   
Department of Radiology, University of Calabar, Nigeria

ABSTRACT

In vitro Sodium Chloride absorption of X-rays was studied with concentrations of 46 mg/mol to 460 mg/mol, which include the range of sodium and chloride ion concentrations in the human body. Irradiation was done with an incident x-radiation dose equivalent of 0.0309 m Sv, with Lithium Fluoride as detector. Absorbed doses read off the thermoluminiscent detectors (TLD) with a TLD reader showed a non uniform variation, but linear relationship between concentration and absorbed dose, with a strong positive correlation of 0.8140. The radiobiological implications of these results are discussed.

Keywords: Sodium Chloride, X-ray, Absorption, concentration, phosphors, selection, patients

 

CHARACTERISTIC DISTRIBUTION OF TOTAL, DIFFUSE AND DIRECT SOLAR RADIATION AT CALABAR

Akpabio, L. E+1. and Udoimuk A. B2.

1Department of Physics, University of Uyo, Uyo

2Department of Physics, University of Calabar, Calabar

ABSTRACT

In this paper, a number of years of data on sunshine duration has been estimated to determine the daily, monthly and yearly distribution of solar radiation at Calabar. Similarly, daily irradiation on a monthly average for several inclinations was computed. A mean irradiance of 14.33MJ/m2 per day is recorded for Calabar.

KEYWORDS: Solar radiation characteristic distribution Calabar.

        

 

AN EXCHANGE ALGORITHM FOR GLOBAL OPTIMIZATION OF A RESPONSE FUNCTION

M. P. Iwundu

Department of Mathematics/Statistics/Computer Science
University of Uyo, Nigeria

Dr. Aniekan Offiong

Department of Mechanical Engineering
University of Uyo, Nigeria

ABSTRACT

A line search technique is introduced for locating the global minimizer of a response surface which may contain several local minimizers.  The main features of the method are that the starting point, direction of search and step-length are optimally chosen, and the sequence is shown to be certain to converge to the global minimizer.  Other methods of finding the global minimizers such as Hesse (1973), Storey (1985), Onukogu (1997) are shown to have their individual limitations and these limitations do not apply to the new technique.

 

Keywords: optimization, response function, exchange algorithm, computation.

 

 

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