Open Access Original Research Article

Investigating the Opportunities for Environmentally Benign Options in the Refrigeration Industry of Uganda

Thomas Makumbi, John Baptist Kirabira, Adam Sebbit, Björn Palm

Current Journal of Applied Science and Technology, Page 1-24
DOI: 10.9734/BJAST/2015/18033

Using synthetic refrigerants has led to ozone depletion, global warming and the associated climate change. This study therefore aimed at investigating the application of environmentally friendly options in the refrigeration industry of Uganda with the main emphasis on refrigerants. A field study was done to assess the current status of refrigeration in Uganda as well as to obtain relevant information for the study using questionnaires, interviews, field measurements and observations. The required data included evaporation and condensing temperatures and pressure, refrigerant mass flow rate, system type, refrigerant type, etc. Using the above data as input, models of the available systems were developed using EES and their efficiencies determined; also, models were proposed for each sector in the industry using an appropriate natural refrigerant(s) and comparison of the efficiencies obtained with those of installed systems was made. EES also assisted in the performance of a parametric study on the system operating parameters. Results from the field survey showed that synthetic refrigerants dominate the industry and the systems installed are single stage vapor compression while those from modeling and simulation reveal that natural refrigerants offer a promising solution in the refrigeration industry of Uganda and should be adopted for energy, safety and environmental reasons. Nevertheless, it is recommended that rigorous testing of the systems with alternate refrigerants proposed be conducted to verify the results of the simulations before full adoption. Furthermore, performing an economic analysis would give better justification for adoption from an industrial point of view. However, the major challenges to be encountered in case of adoption are safety, system modifications especially in systems that are to use R744, lack of technical expertise to design, install, operate and service the systems as well as lack of government policy to spearhead the transition. Therefore for the transition to be realized there is need to come up with policy concerning the use of environmentally harmful refrigerants and also create awareness in the industry.

Open Access Original Research Article

An Evaluation of Climate Responsive Design Features of Buildings on Knust Campus Based on Mahoney Tables

C. Koranteng, S. Amos-Abanyie, S. O. Afram

Current Journal of Applied Science and Technology, Page 1-14
DOI: 10.9734/BJAST/2015/17795

The warm and humid climate of the Kwame Nkrumah University of Science and Technology (KNUST) necessitates that climate responsive buildings are thermally comfortable when laid down design principles are followed in the planning and construction of dwellings. An example of a climatic design guide leading to decision support principles toward the design of buildings is the Mahoney Tables. In this paper, the evaluation of buildings of two colleges which are characterized by old and new constructions is studied. The main aim is to find out which building type (old or new) were constructed based on climatic design principles. The evaluated results based on the Mahoney Tables showed that older buildings (95%) conformed to climatic design principles whilst some recently built structures (40%) were deficient in various aspects of sustainable design principles such as orientation. The study provides a direction and caution designers to use climatic responsive design principles in the planning and construction of buildings.

Open Access Original Research Article

Dormancy Breaking of the Fig Tree with Hydrogen Cyanamide and Garlic Extrate

Sarita Leonel, Marco Antonio Tecchio, Giovanni Marcelo De Angeli Gilli Cóser

Current Journal of Applied Science and Technology, Page 1-10
DOI: 10.9734/BJAST/2015/18194

The supply of cold hours needed to the dormancy breaking of shoots is the limiting factor for the cultivation of temperate climate fruit trees in warmer regions. In subtropical conditions, it is necessary to use chemical products to promote uniform sprouting. This research aimed at evaluating the effect of garlic extract and hydrogen cyanamide in sprouting, growth, production and production cycle of the fig tree. The experiment was conducted during the production cycles of 2011/12 and 2012/13. We used plants from the cultivar Roxo de Valinhos. Production pruning was made in the months of July/2011 and July/2012, and the following treatments were applied immediately after it: 2% hydrogen cyanamide and garlic extract in 4%, 8% and 12% doses, and a control treatment. Split plots were used as the experimental design, with five repetitions in blocks; each plot consisted of five treatments with hydrogen cyanamide, garlic extract and control; the subplots consisted of two production cycles. The use of hydrogen cyanamide promoted an anticipation of sprouting and the use of hydrogen cyanamide and garlic extract promoted a concentration of the productive period, when compared to the control. The estimated garlic extract dose that promoted the highest production per plant was 3%.

Open Access Original Research Article

Global Optimisation of Gasoline Pool Blending Using Constraint Partitioning

Aliyu Musa Aliyu, Sadiq Muhammad Munir, Musa Umaru, Ibrahim Aris Mohammed, Oyewole Adedipe, Baba Yahaya Danjuma, Adegboyega Ehinmowo, Solomon Alagbe

Current Journal of Applied Science and Technology, Page 1-15
DOI: 10.9734/BJAST/2015/18348

Aims: A hybrid Nonlinear Programming–Simulated Annealing method has been applied to solving the constrained offline gasoline recipe optimisation problem using constraint partitioning.
Methodology: The method was demonstrated by applying it to a small blending case study with eighteen independent variables where one of the variables was used as a link variable between the two sub-problems of the partitioned non-convex problem. It is noted that this can in theory be extended to larger tightly constrained problems with more link variables e.g. whole refineries where the models involve huge numbers of nonlinear equations and many process units.
Results: The approach exhibited good performance representing significant savings against both a derivative-based NLP method used alone and a Mixed Integer Non-Linear Programming method. This performance was examined by way of a sensitivity analysis of the simulated annealing parameters.
Conclusion: The convergence times were in minutes and are realistic for short-term recipe optimisation.

Open Access Original Research Article

The Role of Radioactive Iodine in Thyrotoxicosis Patients

B. Z. Shakhreet, M. Q. Alzawad, N. A. Batawil, S. D. Jastaniah, K. G. Alsafi, H. Y. Abbas, S. K. Hagi, M. A. Khafaji

Current Journal of Applied Science and Technology, Page 1-7
DOI: 10.9734/BJAST/2015/15437

Aims: The primary objective of this study is to investigate the treatment of Graves' Disease (GD) with radioactive iodine (131I-NaI), presenting the clinical symptoms suffered from patients, and evaluating the level of triiodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH) before and after the therapy procedure.
Study Design: This project is considered as a retrospective project, non-randomized, observational clinical case series. Clinical symptoms produced by GD were stratified according to patients’ gender and age, and a comparison between T3, T4 and TSH was done before and after the radioiodine therapy.
Place and Duration of Study: This study was conducted under supervision of the Department of Nuclear Medicine, King Abdulaziz University Hospital (KAUH) and the Department of Diagnostic Radiology (KAU), Jeddah, KSA, from November 2012 to May 2013.
Methodology: The records of patients with clinical diagnosis of Thyrotoxicosis who were registered in the nuclear medicine department during academic year 2012-2013 to perform thyroid scan retrospectively were analyzed. Data from 21 patients was collected before and after the administration of radioiodine therapeutic activity. Thyroid scintigraphy and thyroid functional tests (TFT) were conducted on all patients enrolled in the present study.
Results: The most common clinical symptoms produced by GD were tachycardia, weight loss, excessive sweating and tremors. A total of 90% of the patients were under anti-thyroid drug medication before taking radioiodine therapy while 10% were not. TFT results showed that 95% of patients presented abnormal thyroid function. Aside from excessive sweating, no significant association between age and clinical symptoms was observed. A significant increase in TSH level and decrease in T3 and T4 was observed at three-months after therapy procedure. Within six months post-therapy, 60% of patients showed clinical symptoms of hypothyroidism, 30% presented TFT results compatible with normal thyroid function, and only 10% showed no response to treatment.
Conclusion: Radioactive iodine is an excellent alternative for GD treatment compared to other therapeutic approaches, presenting less complication than surgery procedure and reverse possibility when patients are treated with anti-thyroid drug medication.

Open Access Original Research Article

Ensemble Classifier System for Automatic Diagnosis of Thyroid Disease

A. H. El-Baz

Current Journal of Applied Science and Technology, Page 1-13
DOI: 10.9734/BJAST/2015/17613

Thyroid gland secretes hormones that govern many of the functions in our body, such as the way the body uses energy, consumes oxygen and produces heat. Thyroid disorders typically occur when this gland releases too many or too few hormones. An overactive or underactive thyroid can lead to a wide range of health problems. Automatic diagnosis of Thyroid disease via proper interpretation of the thyroid data set is an important classification problem. Thyroid disease dataset which is taken from UCI machine learning database was used. The proposed method uses both Multilayer Perceptron (MLP) and Cascade-Forward Back Propagation Network (CFBN) as base classifiers for the proposed combined classifier systems. The combined classifier is based on varying the parameters related to both the design and training of neural network classifiers. The proposed method achieved accuracy value 96.23% for both combined MLP and combined CFBN classifiers. It has been observed that these results are one of the best results compared with results obtained from related previous studies and reported in the UCI web sites. The experimental results obtained show that the proposed combined classifier can be successfully used for diagnosing thyroid disease.

Open Access Original Research Article

Impact of Parent Zirconia Crystallinity/Amorphicity on the n-heptane Isomerization over Pt/WO3-ZrO2 Catalysts

Dalibor Kaucký, Petr Sazama, Zdeněk Sobalík, José M. Hidalgo, Radek Černý, Oleg Bortnovský

Current Journal of Applied Science and Technology, Page 1-15
DOI: 10.9734/BJAST/2015/18557

A series of WO3-ZrO2 catalysts containing 18% of WO3 were prepared from Zr(OH)4 pre-calcined at temperatures between 25 to 700°C, before W-introduction by impregnation. Thus, in accordance with that, the resulting parent Zr(OH)4 support possessed different degree of crystallinity and proportion of monoclinic to tetrahedral (M/T) phases which directly influenced the same M/T ratio in the final Pt/WO3-ZrO2 catalyst. The resulting catalysts varied in nuclearity and reducibility of formed WOx species, as revealed by UV-Vis spectroscopy and TPR-H2. Despite widely different surface area of the final catalysts, ranged from 140 to 47 m2/g, related to the proportion of M/T phases, ranged from 10%/90% to 90%/10%; the activity of the corresponding Pt/WO3-ZrO2 for isomerization of C7 was found to be directly proportional only to the total surface area of the resulting catalysts without specific effect of the crystal modifications of the support. In accordance with that a correlation was observed between the isomerization activity in n-C7 conversion, ranged from 65 to 31%, and the population of formed poly-nuclear WOx species, ranged from 41 to 33%, directly controlled exclusively by the surface area of the support.

Open Access Original Research Article

Development of Anthropometric Database for Paraplegics in Nigeria

O. Oriola Akinyemi, H. Oluwole Adeyemi, S. Olanrewaju Giwa, T. Bode Adeboje

Current Journal of Applied Science and Technology, Page 1-10
DOI: 10.9734/BJAST/2015/17602

Aims: The main goal of this research is to develop a fresh anthropometric database for disable population in Nigeria.
Methodology: Adequate survey of anthropometric data of Nigeria paraplegics in South-Western Nigeria was carried out with a 31:19 male-female ratio. Suitable and reliable anthropometers were used to collect data on a well-structured questionnaire. Thirty nine (39) body parts of the paraplegics’ population sample were measured and the analysis of the relevant anthropometric measures was carried out using the SPSS Software.
Results: Results show that there are variations in female and male body parts measurements. Based on the need to accommodate at least 90% of the paraplegic population of Nigeria, this paper proposes facilities/workstation design dimensions for waist circumference (50 cm-84 cm), hip-buttock circumference (41 cm-89 cm), waist depth (15 cm-25 cm) for female paraplegics while for male paraplegics are waist circumference (49.6 cm-83.2 cm), hip-buttock circumference (56.76 cm-88.80 cm), waist depth (14.20 cm-24.80 cm) among others.
Conclusion: The information presented from the data analysis will be useful for design engineers in designing equipment, workspace and facilities for Nigeria Paraplegics.

Open Access Original Research Article

Effect of Feed Type on Performance of Nera Black Hens in the Humid Tropical Environment

A. O. Ani, C. E. Oyeagu

Current Journal of Applied Science and Technology, Page 1-12
DOI: 10.9734/BJAST/2015/6051

A twelve-week study was conducted to determine the effect of feed type on performance of Nera black hens in the humid tropical environment. One hundred and twenty (120) Nera Black hens of 28 weeks of age were used for the study at the Poultry Unit of the Department of Animal Science Teaching and Research Farm, University of Nigeria, Nsukka between March and July, 2012. The hens were divided into five groups of 24 hens each and each group was randomly assigned to one of five experimental diets (self-compounded layers’ diet ‘B’ and four commercial layers’ diet A ‘reference diet’, C, D, and E, respectively). Each diet constituted a treatment and each treatment was replicated thrice with 8 birds per replicate. Each hen in a replicate received about 130g of layers’ mash daily and ad libitum supply of water for the twelve weeks. Results showed that the final body weight, hen day production, average daily feed intake and feed conversion ratio, average egg weight, egg shell thickness and egg shell weight were significantly (P<0.05) influenced by treatments, while treatments had no significant (P>0.05) effect on average body weight gain, egg diameter, egg length and egg shape index. Birds that consumed homemade diet (B) had significantly (P<0.05) higher average egg weight than those fed the commercial diets which had similar mean egg weights. While some internal egg parameters were significantly (P<0.05) affected by treatments, others were not affected. Although dozens of eggs produced per bird and revenue from dozens of eggs produced were not significantly (P>0.05) influenced by treatments, total feed consumed, cost of feed consumed and gross profit were significantly (P<0.05) influenced by treatments. It was concluded that the use of homemade diet resulted in better performance than the use of commercial diets in the present study.

Open Access Original Research Article

An Optimized Genetic Approach for Scheduling Task Duplication in Parallel Systems

Jasbir Singh, Gurvinder Singh

Current Journal of Applied Science and Technology, Page 1-12
DOI: 10.9734/BJAST/2015/17171

Task Scheduling deals with the set of tasks assigned to parallel multiprocessor system and the execution order of the schedule so that the total execution time is minimized. The role of a good scheduling algorithm is to efficiently assign each task to a processor depending on the resources needed, the communication overhead between related tasks is reduced and the precedence relations among tasks are satisfied. It can be efficiently used for tasks that have a large calculation, and have time constraints to complete the schedule. The efficient execution of the task scheduling on parallel system takes the structure of the task and the performance characteristics of the proposed genetic algorithm. It falls in the category of NP-complete problem. This study proposes a parallel genetic algorithm-based approach to schedule tasks on parallel system with task duplication heuristics. Task duplication can minimize inter-processor communication and hence results in shorter finish times. Its performance is measured in comparison with the Round Robin (RR), First Come First Serve (FCFS), and Multi-level queue scheduling (MQS), Shortest Job First (SJF), Largest Job First (LJF) and Priority scheduling methods.