Open Access Original Research Article

Fuzzy Adaptive Control Design of Induction Motor Speed Sensorless Based on MRAS

Sheng Ou, Haishan Liu, Qun Peng, Shiyang Qi, Cong Feng, Pinlong Mo, Guoying Liu

Current Journal of Applied Science and Technology, Page 1-8
DOI: 10.9734/BJAST/2016/19893

In order to solve the real-time parameter adjustment problem of the speed sensorless vector control system for the induction motor, the paper presents a fuzzy self-adaptive method with intelligent gain adjustment. By the means of the sensorless vector control for induction motor, adapt Model reference adaptive system (MRAS) to achieve the rotor position estimation to improve the speed and estimated accuracy, and then design the out-loop controller to achieve high response of speed control. So applying the method of the fuzzy self-adaptive parameter adjustment, track and correct controller parameters in time to achieve high dynamic response. The simulation results confirm the validity and effectiveness of the proposed control strategy.

Open Access Original Research Article

Measurement of Thermal Conductivity and Specific Heat Capacity of Three Major Geomorphological Units in Akwa Ibom State, Nigeria

Samuel T. Ebong, Ekaette S. Attai, Emmanuel O. Joshua

Current Journal of Applied Science and Technology, Page 1-7
DOI: 10.9734/BJAST/2016/17834

The thermal conductivity (k) and the specific heat capacity (C) of some samples collected from three major landforms in Akwa Ibom State, Nigeria; namely Beach Ridge Sand (BRS), Coastal Plane Sand (CPS), Sandstone/Shale Hill Ridges (SHR) were measured. Results show that an increase in C of SHR and BRS samples taken from different locations gives rise to decrease in k. The C of the area under study falls within the range 1813.64 Jkg-1K-1 to 3313.24 Jkg-1k-1 while the soil thermal conductivity was between the range 0.272 Wm-1K-1 to 0.451 Wm-1K-1. The C of the soil samples has great effect on crop and construction works

Open Access Original Research Article

Effect of Partially UV-blocking Films on the Growth, Yield, Pigmentation, and Insect Control of Red Amaranth (Amaranthus tricolor)

Abul Hasnat Muhammad Solaiman, Takashi Nishizawa, S. M. Anamul Arefin, Md. Dulal Sarkar, Mohammad Shahjahan

Current Journal of Applied Science and Technology, Page 1-11
DOI: 10.9734/BJAST/2016/20803

Red amaranth (Amaranthus tricolor) was grown in tunnels covered with partially UV-blocking films (<340, <350, <360, and <400 nm) for five weeks after sowing, and plant growth, anthocyanin concentration, and insect burden were compared with those of UV-transmitting films and outdoors. The values of plant height, stem cell length, leaf area, and fresh weight were higher in the plants grown under higher UV-blocking conditions, while the plant dry weight was greater under lower UV-blocking conditions due to the lower dry matter percentage under higher UV-blocking conditions. The red color of the upper leaves became lighter as the UV-blocking rate increased, while there was no such distinct difference in either the lower leaves or stem. Anthocyanin concentrations of both the stem and leaves of the plant apex were significantly lower under UV-blockings than under UV-transmitting conditions and outdoors, but there was almost no significant difference among different UV-blocking rates. Yellow and blue sticky traps were also suspended at the center of the tunnels, and twelve insects were trapped during the experimental period. The maximum invasion by insects and feeding damage of the seedlings were observed outdoors, followed by plants grown under UV-transmitting conditions. Partially UV-blocking conditions significantly reduced invasion by insects and feeding damage of the seedlings compared to outdoors and under UV-transmitting conditions, but there was no significant difference among different UV-blocking rates. The number of herbivores tended to decrease as the UV-blocking rate increased, while that of predators was little affected by the UV-blocking rate. Our results showed that partially UV-blocking conditions were as effective as fully UV-blocking conditions, especially for controlling some herbivores such as aphids and white fly, and also for maintaining an advantageous balance between herbivores and predators. On the other hand, anthocyanin pigmentation of higher plant parts was often inhibited under UV-blocking conditions.

Open Access Original Research Article

Monitoring and Characterization of Soils from River Bed of Beas, India, Using Multivariate and Remote Sensing Techniques

V. Kumar, A. Sharma, R. Bhardwaj, A. K. Thukral

Current Journal of Applied Science and Technology, Page 1-12
DOI: 10.9734/BJAST/2016/21611

River Beas is an important river of India, originating in the Himalayas and merging into river Sutlej in Punjab, at Harike, a Ramsar wetland. Twenty two soil characteristics including eight heavy metals were studied at four sampling sites in the vicinity of the river for pre-monsoon, post-monsoon and winter seasons, over a stretch of 63 km from Beas to Harike towns in Punjab, India. Cluster analysis showed that soil characteristics of each site for all the seasons were different. First three principal components in principal component analysis explained 100% of the total variance for pre-monsoon and winter seasons, whereas 99.99% of the total variance for post-monsoon season. In factor analysis, factor-1 accounted for 36% of the total variance and had strong loadings on pH, conductivity, hydrogen, nitrogen and phosphorus. Textural characteristics explained the factor-2 which accounted for 21% of the variance, whereas water holding capacity (WHC), carbon and nitrogen were explained by the factor-3 with 20% of the total variance. In multiple linear regression analysis, reflectance values from bands 2(green), 3(red) and 4(near infra-red) of Landsat (TM) digital data were regressed on pH, phosphorus, potassium, iron, cobalt and manganese. Cobalt and manganese contributed negatively to the reflectance data, whereas pH, phosphorus, potassium and iron enhanced the reflectance data. Artificial neural network models were fitted to the data. Correlations between the target and output values of bands 2(green), 3(red) and 4(near infra-red) were highly significant.

Open Access Original Research Article

Effect of Active Cooling Control on Internal Combustion Engine Exhaust Emissions and Instantaneous Performance Enhancement

Eid S. Mohamed, Essam M. Allam

Current Journal of Applied Science and Technology, Page 1-16
DOI: 10.9734/BJAST/2016/21685

Energy flows and energy efficiencies in the operation of a modern automobile are development expressed and corresponding on  reduction of pollutant emission from spark ignition (SI)  engines is desirable due to reduce the highly impact on the green environment, the trend toward high engines efficiency has led to new implementation of more intelligent engine thermal management (ETM) systems. However, the present work aims to clear the effect of different cooling systems and operating parameters of the SI engine on their engine performance and emission characteristics. An active coolant control (ACC) as well as of engine ETM has been realized using a variable-speed electrical pump, and a variable-position smart valve which controls the fluid flow rate distribution between the radiator and its bypass line to better regulate heat rejection. Experimental engine cooling systems have been operating assembled two different cooling systems (conventional or ACC). The Nissan SI engine was used as the experimental set-up and equipped with exhaust gas analyzer, Thermocouple sensors and magnetic pickup transducer to measure the exhaust emissions, coolant temperature and engine rotational speed respectively. The measurements were conducted at different engine speed and load torque. The results indicate that most of the carbon monoxide (CO), carbon dioxide (CO2), and unburned total hydrocarbons (THC) emission appears at higher load as well as near the coolant temperature. Nitrogen oxides (NOx) emission was observed to increases because higher coolant temperature contributed to raising combustion temperature, the results show that the arrangement of ACC flow rate and operation in idle state is very effective to reduce exhaust emissions. The assessment results of the experimental tests revealed that warm up period with ACC was decreased by 31%, In addition, CO2, CO, THC, and NOx, of SI engine with ACC were reduced by 11%, 13.5%, 8.4%, 6.2%, and 26.0%, respectively.

Open Access Original Research Article

Performance of Shell and Tube Heat Exchangers with Varying Tube Layouts

Moses Omolayo Petinrin, Ademola Adebukola Dare

Current Journal of Applied Science and Technology, Page 1-8
DOI: 10.9734/BJAST/2016/20021

Shell and tube heat exchangers (STHEs) are the most common type of heat exchangers and are applicable for wide range of operating temperatures and pressures. Numerical analyses on thermal-hydraulic performance of three sets of shell and tube heat exchangers (STHEs) with different geometrical tube layout patterns variations namely; triangular (30º, STHE_T), rotated triangular (60º, STHE_RT) and the combined (STHE_C) patterns were carried out in this study. The results from solving the governing continuity, momentum and energy equations showed that bulk of the heat transfer and pressure drop occur during the cross-flow of shell-fluid through the tube bundles. Evaluation of the performances of the heat exchangers showed that the STHE_T is more desirable followed by the STHE_C as they exhibit higher heat transfer coefficient than the STHE_RT for the same pressure drop in the shell-side.

Open Access Original Research Article

A Hybrid Morphological Based Segmentation Method for Extracting Retina Blood Vessels Grid

Saba A. Tuama, Loay E. George

Current Journal of Applied Science and Technology, Page 1-12
DOI: 10.9734/BJAST/2016/20116

The patterns of retinal blood vessels play major role in many different applications, such as diseases diagnosis and human identification. The accurate segmentation of vessels body appeared in retina images is vital to make successful human identification decisions. This paper presents a new method for vascular network extraction from color retinal images. The proposed method consists of three main stages: Preprocessing, segmentation, and post-processing. Preprocessing stage is applied to enhance the local appearance of blood vessels in retinal images; its main task is to make compensation for the global/local contrast variance over all parts of the retina area, such that the dynamic range for brightness levels of the vessels' pixels becomes narrow and lies in the dark region of brightness scale. In segmentation stage, the grid of retina vessels had been extracted using thresholding method; where the vessels appear dark, thin and connected bodies in retina area. Finally, post preprocessing stage is applied to eliminate the noise and to remove the produced disconnections in the extracted vessels due to thresholding.

The proposed method was tested on the two publicly available datasets: (i) DRIVE (Digital Retinal Images for Vessel Extraction) and (ii) STARE (Structured Analysis of the Retina). The test results indicated that the proposed method is efficient to segment the large vascular areas and outperforms of many introduced methods in the literature. The test results indicated that the attained accuracy of the proposed method was 97.41% in DRIVE dataset, and 97.43% in STARE dataset

Open Access Original Research Article

Relationship between Occupational Stress and Demographic Variables: A Study of Employees in a Commercial Bank in Ghana

Affum-Osei Emmanuel, Azunu Collins

Current Journal of Applied Science and Technology, Page 1-9
DOI: 10.9734/BJAST/2016/21460

Occupational stress is inevitable in the workplace and has become a global issue which has attracted much research in recent times. The current study aims at finding the relationship between occupational stress and demographic variables (gender, age, qualification, experience and marital status) in Ghana. A descriptive correlation survey was used in the study. Questionnaire was the main instrument used to gather the data for the current study. A total of 206 employees were randomly selected from 10 branches of a commercial bank in Ghana. The results showed that majority of the employees were moderately and highly stressed with female workers recording the highest level of occupational stress compared to their male counterparts. The study further indicated that, there is evidence of significant relationship between occupational stress and demographic variables (gender, age, qualification, experience and marital status). In conclusion, employers should take note and take the necessary measures to ameliorate occupational stress based on individual differences since individuals differ in their response to stressful situations. Organisations’ stress policies should therefore, only be expected to deal with occupational stress issues anything else would adversely affect employees and the organization as a whole.


Open Access Original Research Article

Periodic Acid Schiff Reactions and General Tissue Morphology of Conventionally-processed versus Two Rapid Microwave-processed Tissues

Anthony Ajuluchukwu Ngokere, Tobias Peter Pwajok Choji, Samuel Ifedioranma Ogenyi, Peterside Rinle Kumbish, Gyang Davou Moses, James Saidu Ahmed, Isa Suleiman, Ruth Idzi Zamfara, Simon Mshelbwalaa Bukar, Victoria Davou Gwong

Current Journal of Applied Science and Technology, Page 1-14
DOI: 10.9734/BJAST/2016/19710

Aims: To utilise the laboratory microwave as an instrument for a faster, cheaper and reliable tissue processing in the paraffin technique, to establish a processing schedule that eliminates xylene and replace it with a suitable alternative. To check the effect of microwave processing techniques on glycogen reactions as well as tissue morphology.

Study Design: Animal acquisition, sacrifice, harvesting and fixation of tissues. Grossing into triplicates, processing using three different techniques namely the conventional paraffin wax method, the microwave without vacuum method and the microwave with vacuum method. Staining using the PAS-Diastase as well as Haematoxylin and eosin staining techniques. Assessment and grading of morphology and staining characteristics.

Place and Duration of Study: Apparently healthy rabbits from the animal house, National Veterinary research Institute, Vom, Jos, Nigeria, between August and December, 2014.

Methodology: Two apparently healthy rabbits were sacrificed. The lungs, heart, liver, kidney, stomach, and spleen of each were harvested and fixed in 10% buffered formalin for three days. They were grossed into triplicates, labeled and processed using the conventional, microwave without vacuum and microwave with vacuum respectively. They were sectioned and stained simultaneously using the PAS-Diastase as well as H & E staining techniques. They were graded as excellent if they permitted microscopy, fair if not very good but can permit microscopy and poor if they cannot permit microscopy at all. Statistical data generated were processed using one way analysis of variance (ANOVA) at 95% confidence interval.

Results: Processing cycle as well as quantity of reagent used per cycle is greatly reduced in the microwave techniques. Tissue morphology, special features as well as glycogen were clearly demonstrated without significant differences. Dye uptake as well as section thickness were comparable among the three techniques. Block durability is comparable among the three techniques after 64 weeks of storage. There was no statistically significant difference in details of microscopic assessment/quality of tissue preservation (P=.90) and details of microscopic assessment/quality of staining (P=.74).

Conclusion: Same-day turn-around is possible in histology, with reduced reagent consumption and elimination of xylene, without compromising section quality, dye uptake or the reactions of glycogen in the PAS-Diastase technique. This will result to quick diagnosis hence quick intervention at a cheaper rate to both laboratories and clients. It is a good innovation in forensic and diagnostic histopathology and should be encouraged. Its compatibility with other histochemical techniques, immunohistochemical and molecular techniques should be evaluated to give a wider application.

Open Access Original Research Article

Impact of External Audit Quality on Earnings Management by Banking Firms: Evidence from Jordan

Mohammad Ebrahim Nawaiseh

Current Journal of Applied Science and Technology, Page 1-14
DOI: 10.9734/BJAST/2016/19796

Purpose: The aim of this exploratory research is to test the prediction that external audit quality is positively associated with earnings management. Whilst the main significance it can help stakeholders predict earning management based on some proxies that are not publicly available in annual reports.

Design/Methodology/Approach: This study investigates the informative of audit quality for estimate in earning management (EM) during the period of (2006-2010) of Jordanian Banking Firms listed in Amman Stock Exchange (ASE). Some leading proxies taken based on audit quality; Audit tenure (AT), Audit fees (AF), and the affiliation with international big auditing firms (INT). Moreover, other controlling variables; Financial Leverage (FL), (Return on Assets) ROA, (Return on Equity) ROE, (Cash flow/Total assets) CFO, and EM already taken in the analysis. The population of the study includes examining (13) Jordanian working commercial Banks over a five year period, The author tested the effects of audit quality on earning management using the panel data methodology.  

Findings: The paper finds that; (AT), (AF), and the (INT) have significant relations with earning management. It means, future earning management forecast is predictable based on audit quality leading indicators (AT, AFEE, and INT). In addition to company size, that is, when external auditing is conducted, earning management mitigates. Moreover, no relationship is found between Leverage, ROA, CFO, and   Earning management.

Originality/Value: This research examines earning management forecast based on audit quality leading indicators (AT, AFEE, and INT) in addition to the company size. These groups; whether commercial banks, or audit quality indicators, have not been well researched in the past literature, especially in the Jordanian Banking Sector.