Open Access Original Research Article

Monitoring of the Respiration Activity of Sewage Sludge and Biofractions of Municipal Waste in the Composting Process

Sylwia Myszograj, Katarzyna Kozłowska, Piotr Gramza

Current Journal of Applied Science and Technology, Page 1-11
DOI: 10.9734/BJAST/2016/23153

Introduction: Rational waste sludge disposal means utilizing its fertilizing and calorific properties to their maximum. The ability to convert sewage sludge depends on many factors. Fermented or aerobically stabilized sludge contains components easily assimilable by plants, but its utility in agriculture or gardening is limited. However, stabilization of sewage sludge in the composting process ensures a beneficial modification of its sanitary and epidemiological condition, as well as significantly improving the organoleptic properties, such as odor, color, and granulation; this stabilization also influences the fertilizing value. Before utilizing the compost created from sewage sludge or other bio-waste, it is necessary to check the degree of its stabilization by evaluating the biological activity. One of the methods of evaluating the biological activity of compost is the respiration test, e.g. using the AT4 test (Static Respiration Index). Literature data of respirometric tests show the availability of substrates for microorganisms; in other words, the susceptibility of a substrate to further biodegradation.

Aims: This article analyzes the results of biological activity tests (AT4) of compost from installations for the aerobic stabilization of sewage sludge and biofractions of municipal waste. The aim of the study was the observation of changes to the degree of stabilization of substrates, during a period of 10 weeks of aerobic processing.

Methodology: The studies on a technical scale were conducted at the mechanical and biological processing of municipal waste (MBP) and selectively gathered green waste and bio-waste processing (composting) installation. The fermented sewage sludge was composted together with the organic substrate acquired from municipal waste. The process was conducted during a period of 10 weeks. Every 7 days samples were taken from the aerated heap in order to determine the moisture, ignition loss, and AT4 parameter. The measurements of the compost’s biological activity were conducted using an OxiTop® Control measurement system.

Results: The mixture of municipal waste biofractions and fermented sewage sludge that made up the heaps turned for the composting process was characterized by the following parameters: moisture – 61%, organic substance content – 58% of dry matter, AT4 – 64.5 gO2/kg of dry matter. Continued monitoring of temperature changes (average temperature 39°C/61-67°C/55-35°C respectively) in the heaps confirmed the correct course of the composting process in three phases. After 10 weeks of the process a reduction of organic substances by 54% was achieved, while the value of the AT4 parameter in the stabilized compost was 4.9 gO2/kg of dry matter.

Conclusion: The study results show that changes to the content of organic substances in waste subjected to the composting process are directly proportional to changes of the AT4 parameter, which characterizes the respiration activity of substrates. This correlation can be fairly accurately described by a linear equation (R2=0.93).

Open Access Original Research Article

Mechanical Properties of Healthy and ex vivo Onychomycosis Nails and the Influence of a Porphyrin-propylene Glycol Antifungal Formulation

Amu Hosseinzoi, Federica Galli, Luca Incrocci, Threes Smijs

Current Journal of Applied Science and Technology, Page 1-14
DOI: 10.9734/BJAST/2016/23177

Aims: To investigate nail penetration enhancing effectiveness of a novel drug formulation and ingredients, 40% propylene glycol (PG) and 40 µM multifunctional photosensitizer (MFPS). Proposed formulation was proven effective in photodynamic treatment (PDT) of ex vivo fungal infections of human nails (onychomycoses) and indirectly also to weaken nail’s strength.  

Study Design: To directly proof the effect of the novel formulation on nail’s hardness Atomic Force Microscopy (AFM) was employed to measure small-distance forces. Based on indentations Young’s moduli of healthy and ex vivo onychomycosis nails were calculated before and after treatment with the novel formulation. Changes in young’s modulus can be related to changes in nail’s strength and thus formulation effectiveness. Additionally, AFM imaging was employed to study topographical / roughness changes resulting from the treatments to both nail types. Trichophyton mentagrophytes, representative for clinical onychomycosis, was chosen to induce nail infections. 

Place and Duration of Study: AFM study was performed at Leiden Institute of Physics (Leiden University, The Netherlands). General study design, chemical and microbiological investigations took place at Erasmus MC (Rotterdam, The Netherlands).

Methodology: Tapping mode was used for imaging and contact mode for indentations. For each healthy and onychomycosis nail 5 to 6 spots of 8 x 8 µm on marked areas were studies (3-5 image scans and 5-10 indentations performed per spot). Young’s moduli were calculated using the Hertz model. 

Results: MFPS, PG and MFPS/PG affected healthy nail topography; roughness remained unchanged (PG; MFPS; MFPS/PG) or decreased (MFPS; MFPS/PG). Roughness of onychomycosis nails was lower compared to healthy nails and reduced after MFPS/PG treatment. Healthy nail Young’s moduli varied (1-18 GPa) but decreased significantly after MFPS or PG treatment. Young’s moduli of onychomycosis nails were lower compared to healthy nails and seemingly increased after MFPS/PG treatment.

Conclusion: Human nails are extremely inhomogeneous (strength / topography) thereby influencing topical drug response.

Open Access Original Research Article

Robust Watermarking for Video Using Modulation Technique on RGB Domain

Zainab J. Ahmed, Loay E. George

Current Journal of Applied Science and Technology, Page 1-10
DOI: 10.9734/BJAST/2016/23171

In this paper, a robust invisible watermarking system for digital video encoded by MPEG-4 is presented. The proposed scheme provides watermark hidden by embedding a secret message (watermark) in the sprite area allocated in reference frame (I-frame). The proposed system consists of two main units: (i) Embedding unit and (ii) Extraction unit. In the embedding unit, the system allocates the sprite blocks using motion compensation information. The allocated sprite area in each I–frame is used as hosting area for embedding watermark data. In the extraction unit, the system extracts the watermark data in order to check authentication and ownership of the video. The watermark data embedding method is Blocks average modulation applied on RGB domain. The applied modulation technique is based on making uniform quantization to the block mean value of the color bands. The tests indicated that the proposed block mean modulation method of the sprite blocks showed robust watermark embedding; it was capable to withstand against lossy JPEG.

 

Open Access Original Research Article

Impact of Performance Evaluation Criteria on Intelligent Tuning

Mohammed Majid M. Al Khalidy, Luisella Balbis

Current Journal of Applied Science and Technology, Page 1-14
DOI: 10.9734/BJAST/2016/23146

This paper addresses the problem of automatically tuning in an intelligent manner so that a balance between efficiency and computational speed is reached. In this paper a new proposed technique which uses Particle Swarm Optimization (PSO) to compute the best optimal value for the PID parameters are presented. In this study two different performance criteria are used simultaneously for the optimization problem, namely Integral of Time-weighted Absolute Error (ITAE) and an output response based performance criteria (Fitness Function). The integration between the two performance criteria produces two distinct tuning techniques called Error-Fitness PSO (EFPSO) and Fitness-Error PSO (FEPSO). This paper also proposes new modified Time Varying Acceleration Coefficients (TVAC) that is used in the PSO algorithm. Finally, simulation experiment on a single degree of freedom robotic arm shows that the proposed techniques can produce optimal PID gains with good computational efficiency and improved step response characteristics. The proposed integration techniques can highly improve the PID tuning optimization in comparison with the one that use only one technique.

 

Open Access Original Research Article

Anions, Total Petroleum Hydrocarbons and Aromatic Hydrocarbons in Soils of Aba Dumpsites

E. C. Ogoko, Kelle Henrietta Ijeoma

Current Journal of Applied Science and Technology, Page 1-8
DOI: 10.9734/BJAST/2016/22084

 

This study was intended to evaluate the extent of contamination of soils in the vicinity of some selected dumpsites (Enyimba, Ogbor Hill and World Bank) in Aba Metropolis by anions (nitrate, sulphate and phosphate), polycyclic aromatic hydrocarbon and total petroleum hydrocarbon. Soil samples were obtained in triplicate on monthly intervals for three consecutive months during dry seasons in three different dumpsites and a neighborhood reference site (Aba North Industrial Layout). These soil samples were then analysed for anions, total aromatic hydrocarbons and total petroleum hydrocarbon.  Analysis of total aromatic hydrocarbons and total petroleum hydrocarbons were performed by gas chromatographic method whereas spectrophotometer (model 2000) was used in evaluating nitrate, sulphate and phosphate concentrations in the soil samples. Nitrate content ranged from 980.0 to 2120.3 mg/Kg (Enyimba dumpsite), 850.25 to 1120.3 mg/Kg (Ogbor Hill Dumpsite) and 102.43 to 1980.72 mg/Kg (World Bank Dumpsite). Sulphate concentrations which ranged from 78.99 to 121.21 mg/Kg at the dumpsites were higher when compared to values obtained from reference samples (21.65 to 94.50 mg/Kg). The levels of phosphate in the soil samples from the dumpsites ranged from 9.63 – 15.10 mg/Kg, 7.13 – 12.25 mg/Kg and 5.10 – 10.80 mg/Kg, in Enyimba Dumpsite, Ogbor Hill Dumpsite and World Bank Dumpsite respectively. The concentration of phosphate in the reference samples demonstrated lower values (2.78 – 5.80 mg/Kg) when compared with those from dumpsites. The total polycyclic aromatic hydrocarbons (PAHs) distribution in the dumpsites and the reference site were Enyimba dumpsite (3.27 to 4.32 mg/Kg), Ogbor Hill Dumpsite (2.51 to 3.85 mg/Kg), World Bank Dumpsite (2.15 to 3.98 mg/Kg) and Aba North Industrial Layout (0.05 to 0.09 mg/Kg) respectively. The concentration of TPH ranged from 102.7 to 1340.4 mg/Kg, 93.9 to 1107.3 mg/Kg and 99.10 to 1098 mg/Kg for Enyimba, Ogbor Hill and World Bank dumpsites respectively. The samples from Aba North Industrial Layout recorded the least concentration levels ranging from non detectable limits to 0.09 mg/Kg. The results however, revealed a depth-wise steady decrease in concentrations across the soil (depth) profile with Enyimba dumpsite having elevated levels of all the parameters evaluated when compared with  other study stations. There was no contamination activity found in samples obtained from reference site (Aba North Industrial Layout) unlike in the dumpsites besides the levels of total petroleum hydrocarbon (TPH) indicates potent health risk in the environment of the dumpsites.

 

Open Access Original Research Article

An Experimental Study of the Influence of Open Channel Hydraulic Parameters and Soil Gradation on Jet Pump Sand Removal`s Efficiency

Mohammed Salah, Mamoud Zayed

Current Journal of Applied Science and Technology, Page 1-10
DOI: 10.9734/BJAST/2016/23000

Removing deposits is one of the most important maintenance activities that applied to irrigation canal. This research aims to study experimentally the effect of different flow conditions such as discharge and water depth on removing sand by using jet pump. To achieve this goal, an experimental program was set up and a small prototype of jet pump was tested under different conditions. The flow discharge, water depth and sand type were related to sand remove by the jet pump. Forty five runs were applied on the physical model built in the hydraulic lab of the Channel Maintenance Research Institute, National Water Research Center, Egypt. It was found that both of water depth and discharge of open channel had no direct effect on jet pump efficiency. The efficiency of jet pump was mainly affected by soil gradation. Finally, it is recommended to use jet pump in limited maintenance work where the soil is loose. 

 

Open Access Original Research Article

Synthesis, Characterization and Thermal Properties of New and Known 1,3-Benzo- and Naphtho-Oxazine Monomers Obtained Using a Modified Step-wise Procedure

Abdullahi U. Garin Gabbas, Mansor B. Ahmad, Norhazlin Zainuddin, Nor Azowa Ibrahim

Current Journal of Applied Science and Technology, Page 1-10
DOI: 10.9734/BJAST/2016/23494

New and known 1, 3-benzo- and naphtho- oxazine monomers were synthesized using a modified step-wise procedure in which formaldehyde which is a suspected human carcinogen and a confirmed animal carcinogen was replaced with methylene bromide for ring-closure reaction. Salicylaldehyde and 2-hydroxy-1-naphthaldehyde were separately condensed with the primary aromatic amines p-toluidine, p-phenylenediamine and 4-butylaniline to give imine compounds which on reduction with NaBH4 yields 2-hydrobenzylamines / 2-hydroxynaphthylamines depending on the 2-hydroxyaldehyde used. The 2-hydroxybenzylamines / 2-hydroxynaphthylamines subsequently undergo ring-closure reaction with methylene bromide in absolute alcohol to give 1, 3-benzoxazine and naphthoxazine monomers in good yields. The chemical structures of the synthesized compounds were confirmed using FT-IR, 1H and 13C NMR spectral analysis and mass spectrometry (GC-MS). The thermal properties of the synthesized compounds were determined using Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). From the result of thermal analysis, it may be concluded that the bifunctional monomers show higher glass transition temperature (Tg) and better thermal stability than the monofunctional monomers.

 

Open Access Original Research Article

Modelling of the Operation of a Small Generator Set Powered by Scrubbed Biogas from Cow Dung

J. K. Tangka, C. T. Ketuma, N. Ajaga, C. T. Viyoi

Current Journal of Applied Science and Technology, Page 1-8
DOI: 10.9734/BJAST/2016/22903

This study involved investigation of the impact of the various factors affecting the use of biogas in a modified gasoline generator. A 1.5 kW gasoline generator was modified to function with biogas by advancing the engine timing and installing a Bernoulli suction device in the carburetor. Biogas produced was purified by removing carbon dioxide, hydrogen sulphide and water vapor in this sequence before introduction into the engine of the generator. Various factors associated with engine performance were investigated including, biogas fuel consumption rate, maximum power output, NOx emissions, CO emissions and the overall efficiency. Results indicated a biogas fuel consumption of 6 litres per minute or 3.6 m 3 per hour. The maximum power output was 0.91 kW giving a power drop of about 39%/ The maximum overall efficiency of the biogas fuelled generator set was 15%. NOx and CO emissions were 742 and 30 ppm respectively.

 

Open Access Original Research Article

Cumulative Uncertainty in Measured Groundwater Iron Content of Rigasa Watershed, Kaduna

O. S. Owolabi, C. N. Okafo, M. O. Nwude

Current Journal of Applied Science and Technology, Page 1-11
DOI: 10.9734/BJAST/2016/21541

Fresh water quality has become the principal limitation for sustainable development in many countries and the major human and environmental health dimensions of the global fresh water quality problem is constituted in numerous effects of water borne diseases. Therefore, the assessment of water quality, its management and regulation rely on the water quality data. The aim of this paper is to establish the measurement uncertainty in groundwater quality data in Rigasa Watershed Area in the north-west of Kaduna Metropolis. Measurement uncertainty results from the water quality data monitoring methods. When uncertainty is not considered in measurements it results in un-optimized monitoring projects, unsustainable water resources development and management, and lack of ecosystem security considering their cost-effectiveness and data quality when measurement uncertainty and alternatives to reduce uncertainty are not included in the projects design and implementation. Water quality assessment of the boreholes in Rigasa Watershed was carried out for a period of 12 months to portray the regimes of the phenomena and establish the uncertainty in the measured data. Iron content among the various parameters measured in the boreholes water was found to be in excess of the required limits by the World Health Organization (WHO) and thus formed the focus of this paper. The measurement result showed that the Fe content in groundwater sample was 3.189 mg/l, with the expanded uncertainty measurement ±1.482 mg/l (coverage factor, k = 2, at confidence level 95%). The significant uncertainties showed that the measured values were largely spread around the mean values of the measurand.

 

Open Access Original Research Article

The Bradford Multi-Modal Gait Database: Gateway to Using Static Measurements to Create a Dynamic Gait Signature

Hamad M. Alawar, Hassan Ugail, Mumtaz Kamala, David Connah

Current Journal of Applied Science and Technology, Page 1-10
DOI: 10.9734/BJAST/2016/13426

Aims: To create a gait database with optimum accuracy of joint rotational data and an accu-rate representation of 3D volume, and explore the potential of using the database in studying the relationship between static and dynamic features of a human’s gait.

Study Design: The study collected gait samples from 38 subjects, in which they were asked to walk, run, walk to run transition, and walk with a bag. The motion capture, video, and 3d measurement data extracted was used to analyse and build a correlation between features.

Place and Duration of Study: The study was conducted in the University of Bradford. With the ethical approval from the University, 38 subjects’ motion and body volumes were recorded at the motion capture studio from May 2011- February 2013.

Methodology: To date, the database includes 38 subjects (5 females, 33 males) conducting walk cycles with speed and load as covariants. A correlation analysis was conducted to ex-plore the potential of using the database to study the relationship between static and dynamic features. The volumes and surface area of body segments were used as static features. Phased-weighted magnitudes extracted through a Fourier transform of the rotation temporal data of the joints from the motion capture were used as dynamic features. The Pearson correlation coefficient is used to evaluate the relationship between the two sets of data.

Results: A new database was created with 38 subjects conducting four forms of gait (walk, run, walk to run, and walking with a hand bag). Each subject recording included a total of 8 samples of each form of gait, and a 3D point cloud (representing the 3D volume of the subject). Using a P-value (P<.05) as a criterion for statistical significance, 386 pairs of features displayed a strong relationship.

Conclusion: A novel database available to the scientific community has been created. The database can be used as an ideal benchmark to apply gait recognition techniques, and based on the correlation analysis, can offer a detailed perspective of the dynamics of gait and its relationship to volume. Further research in the relationship between static and dynamic features can contribute to the field of biomechanical analysis, use of biometrics in forensic applications, and 3D virtual walk simulation.