Showing papers in "Journal of Applied Sciences in 2010"

Preparation and characterization of polylactic acid/polycaprolactone clay nanocomposites

Abstract: Biopolymer nanocomposites, which have attracted much attention due to their biodegradability and biocompatibility, have been prepared by melt blending polylactic acid (PLA)/polycaprolactone (PCL) and two types of organoclay (OMMT) include octadecylamine-montmorillonite (ODA-MMT) and fatty hydroxamic acid- montmorillonite (FHA-MMT). Materials were characterized using X-ray Diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), elemental analysis and scanning electron microscopy (SEM). Mechanical properties were also investigated for these nanocomposites. The nanocomposites showed increasing mechanical properties and thermal stability. XRD results indicated that the materials formed intercalated nanocomposites. SEM morphology showed that increasing content of OMMT reduces the domain size of phase separated particles. Additionally, a solution casting process has been used to prepare these nanocomposites and characterized to compare these results with above process. These nanocomposites offer potential for diversification and application of biopolymer due to their good properties such as improved thermal and mechanical properties.

A Novel Embedding Method to Increase Capacity and Robustness of Low-bit Encoding Audio Steganography Technique Using Noise Gate Software Logic Algorithm

Abstract: In this study, we developed a novel method that is able to shift the limit for transparent data hiding in audio from the fourth LSB layer to the eighth LSB layer, thus the method has improved the capacity and robustness of data hiding in the audio file using a two steps approach. In the first step, noise gate software logic used to obtain a desired signal for embedding the secret message of the input host audio signal (carrier). In the second step, standard 8th LSB layer embedding has been done for this desired signal. Audio quality evaluation has used to evaluate our purposed method in two ways. First, objective test showed the algorithm succeeds in this task, while increasing SNR values of our algorithm comparing to SNR values obtained by standard LSB embedding in the 8th bits LSB layer and the comparison of the histogram audio excerpts has proved this also. Second, subjective listening test proved that high perceptual transparency is accomplished even if eight LSB of host audio signal are used for data hiding.

A comparison of time series forecasting using support vector machine and artificial neural network model

Abstract: Time series prediction is an important problem in many applications in natural science, engineering and economics. The objective of this study is to examine the flexibility of Support Vector Machine (SVM) in time series forecasting by comparing it with a multi-layer back-propagation (BP) neural network. Five well-known time series data sets are used in this study to demonstrate the effectiveness of the forecasting model. These data are utilized to forecast through an application aimed to handle real life time series. The grid search technique using 10-fold cross validation is used to determine the best value of SVM parameters in the forecasting process. The experiment shows that SVM outperforms the BP neural network based on the criteria of Mean Absolute Error (MAE). It also indicates that SVM provides a promising technique in time series forecasting techniques.

Hiding Data in Video File: An Overview

Abstract: The aim of this review is to study the methods of steganography using the video file as a cover carrier The steganography is the art of protecting the information through embedding data in medium carrier, for instants this study illustrate historically this art, as well as the study describes methods as a review for this art in the video file The video based steganography can be used as one video file, separated images in frames or images and audio files Since that, the use of the video based steganography can be more eligible than other multimedia files As a result of this study, the video based steganography has been discussed and the advantages of using the video file as a cover carrier for steganography have been proposed

On the capacity and security of steganography approaches: An overview

Abstract: The aim of this study is to review the strength and weakness for the possible multimedia cover for the steganography approaches. In addition, the security level of each approach and how is probable to combine the steganography and cryptography. Steganography is an art on which the data can be hide in other data as cover, the multimedia files is the commonly used for hiding data. The main aspects of the steganography is the capacity and security, where the capacity refer to how much data can be hidden in the cover carrier, while the security concern with the ability of disclose or altering the data by unauthorized party. The multimedia files, such as, image, video, audio and text are the possible covers for hiding secure information or data. Each of these covers has advantages and disadvantages; as a result of this study we will discuss the possibility to use these files as a cover. In the last part of this study, we suggest a further direction to improve the capacity and security aspects.

A review on rheological properties and measurements of Dough and gluten.

Abstract: The field of rheology has seen a wider application in the food industry recently although, it is a complex concept and that most food systems possess non-ideal characteristics. Nevertheless, the rheological behavior of foods are able to be determined using various techniques and equipment. Studies on rheological properties related to dough and gluten are often challenging due to its variance in nature and high dependence on many factors. This study attempts to give a review on the various types of experimental techniques and set-up used in quantifying rheological properties of dough and gluten. The rheological properties are defined and the behaviors are described by inducing stress and strains in small and large deformation studies.

Flood Estimation Studies using Hydrologic Modeling System (HEC-HMS) for Johor River, Malaysia

Abstract: This study presented a flood estimation model for Johor River in Kota Tinggi watershed, Malaysia using HEC-HMS (Hydrologic Modeling System). Calibration and validation processes were carried out using different sets of data. Evaluation on the performance of the developed flood model derived using HEC-HMS yield a correlation coefficient R super(2) close to 1. The simulated Q sub(peak) are 150.9 m super(3) sec super(-1), while the observed Q sub(peak) for 10 years record (1997-2006) is 145.12 m super(3) sec super(-1). The percentage of error values are 4% and the performance of the developed flood model derived using the HEC-HMS with R super(2) value is 0.905. Based on these findings, it is suggested that the developed model using HEC-HMS can be used as a tool for estimating Q sub(peak).

Optimal Capacitor Placement in a Radial Distribution System using Harmony Search Algorithm

Abstract: Modern electric energy are generated from generating station and it deliver to the customer through transmission and distribution network. Most electrical equipment such as motors, lamps and heaters required constant voltage in order to operate. Transmission and distribution system are not required to carry active power but it must also carry magnetizing for inductive load at consumer side. It is essential that the generator at generating station produce active and reactive power. In order to supply and produce reactive power, shunt capacitor are widely used. There are several benefit of shunt capacitor installation in distribution system such as reactive power compensation, power factor correction, system capacity released , power support , reduction in loss and voltage improvement. In this study, the placement of shunt capacitor and optimal capacitor size will be carried out. The result are then compare with others technique in term of capacitor installation cost saving. In this study, loss reduction and voltage profile improvement are studied. It is shown that almost 14% of the losses contribute at distribution system. It also very important to determine the appropriate location of capacitor in order to reduce the system power loss and total capacitor cost. In this study, the main objective is to find the optimal capacitor placement using a new meta-heuristic approach, Harmony Search Algorithm in radial distribution system which is then to reduce power loss and improve the system voltage profile. Simple backward forward sweep power flow is used to determine the power flow in the system. The performance of proposed algorithm is test using 9 bus system and compare with other meta-heuristic approach, Particle Swarm Optimization.

Prediction of User Acceptance and Adoption of Smart Phone for Learning with Technology Acceptance Model

Abstract: This study examines how the Technology Acceptance Model (TAM) can be used as a practical tool for early user acceptance and adoption of testing mobile communication devices for learning by evaluating the relationships among perceived usefulness, perceived ease of use, attitude towards using, behavioural intentions to use and actual use. In the study, 60 potential users were presented with an introductory demonstration of smart phone for a digital systems course. Following the demonstration, data on user perceptions and attitudes about smart phones were gathered based on this initial exposure. Subjects with prior experience using the smart phones were eliminated from further analysis resulting in a final sample of 40 users. Hierarchical multiple regression was used to assess the overall model and influence of each variable of interest in determining actual use of smart phone. The analysis showed that both the user perceptions and attitudes have significant positive effects on behavioural intention and actual use of smart phone. Implications of these findings for practice and research are examined.

Effect of Different Factors on the Acoustic Absorption of Coir Fiber

Abstract: Mohd Jailani Mohd Nor, Md. Ayub, Rozli Zulkifli, Nowshad Amin and Mohammad Hosseini Fouladi

Crude Oil Fouling: A Review

Abstract: Fouling in crude preheat train heat exchangers in refineries is a complex phenomenon. Crude oil fouling undergoes different mechanisms at different stages of preheating. Understanding the fouling mechanisms is essential in formulating appropriate fouling mitigation strategies. The use of the concept of threshold fouling conditions is one of the approaches for mitigating fouling through operating conditions. In this study, an attempt has been made to review the various fouling models available in literature, their advantages and limitations.

Personnel selection using ELECTRE

Abstract: Selecting personnel are an important problem, yet often difficult task. It is complicated because of more than one dimension. This study considers a real application of personnel selection with using the opinion of experts by one of the group decision making model, it is called ELECTRE method. This study has applied seven criteria that they are qualitative and positive for selecting the best one amongst five personnel and also ranking them. The personnel that were in the same grade in ELECTRE method were identified and were re-ranked by using AHP method. We have also used from five expert’s opinion. Finally the introduced method is used in a case study.