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Journal ID : TRKU-20-11-2021-11505
Total View : 338

Title : Least Significant Bit and Discrete Cosine Transform Methods for Audio Steganography

Abstract :

Sending important information over the Internet has become a norm nowadays. Protection must be done so that information is not easily hacked and misused. Steganography is one of protection method in which hidden information is inserted into a digital multimedia channel. This paper aims to hide image messages into audio files with different formats using the Least Significant Bit (LSB) and Discrete Cosine Transform (DCT) approaches. We conducted a performance test by measuring the Peak Signal to Noise Ratio (PSNR), endurance to compression, and transparency of the host that has been inserted the message. The results showed that the PSNR value of audio files through the DCT process was greater than that of LSB, subjective assessment of the mean opinion score related to audio files through the LSB process was better than DCT, and all audio files did not have resistance to a compression mode.

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Journal ID : TRKU-15-11-2021-11503
Total View : 453

Title : Assessment of Service Quality and Customer Satisfaction using SERVQUAL Model in Palestinian Automobile Industry

Abstract :

This study aims at investigating the service quality and customer satisfaction in automobile aftersales services, using the SERVQUAL Model. The study examined the variables that affect the customers’ satisfaction in aftersales service centers, and assess the service quality using the SERVQUAL model. The study employs a quantitative research approach, by developing and distributing two questionnaires to a sample of 250 respondents to assess service quality and customer satisfaction in the automobile industry. The research mainly found that some service centers need to put more effort and emphasis to enhance the assurance, reliability, empathy, and tangibles dimensions. It is noted that people in all of the targeted service centers are expecting the service providers to invest more in the tangibles, and to install more visually attractive physical materials and facilities. Being the first in this field, the outcomes of this study shall be used as a reference to advance and enhance the automobile aftersales sector in the future, and support car dealers and service centers in improving the quality of their offered services to ensure customers’ optimal satisfaction.

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Journal ID : TRKU-12-11-2021-11502
Total View : 457

Title : Functionality Analysis of Open Public Spaces of Darwaza city in Sulaimanyah KRG- Iraq as a case study

Abstract :

Globally due to the urbanization and the population growth in the urban centers, the problems of short come of resources, economics, and the need for high density dwellings arise. The idea of high density housing in the form of small communities arise as a solution to overcome the short come of dwellings and to provide shelter for great numbers of people on a smaller areas of land. This trend has shown up in Kurdistan region of Iraq from the beginning of 2000s, which makes an important topic of interest and necessary to be investigated to guarantee the life and wellbeing of the residents living in these communities, and this is why this paper is trying to analyze the spatial planning of the layouts and the use of public spaces in these communities (Darwaza city as a case study), because the use of public spaces mainly affects the social interaction of the residents, and the vitality of these spaces and positive interaction affects the well-being and psychology of the residents. Many fields of psychology, social sciences, and many urban researchers tried to investigate and understand the relation between built environment and human through many theoretical concepts, and evaluative methods to draw conclusion that promote the use of these public spaces. This paper tried to use space syntax as a theoretical framework and an analytical method using Depthmap program, because it is proven that space syntax is able to analyze quantitatively the relationship between people’s behavior and spatial configuration, and this study tries to overlap the results of people use of space obtained from direct observation and the analysis of the spatial configuration obtained from space syntax. The analysis shows interesting results of people’s use of space and correlations between space use and syntactical variables.

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Journal ID : TRKU-11-11-2021-11501
Total View : 435

Title : Effect of N,N, Dimethyl Formamide (DMF) Volume Fraction and Activation Process on HKUST-1 Synthesis and its Properties

Abstract :

DMF is a common solvent using for HKUST-1 synthesis in solvothermal process. As solvent it is commonly believed that DMF to a certain degree will play role on the quality of final product. This research explores the possibility to enhance HKUST-1 quality by optimizing the usage of DMF during synthesis process. The experiment was performed by preparing solvent that consist of aquadest, ethanol, and DMF. Three samples (A,B, and C) were prepared using DMF that has volume fraction of 0.222; 0.333; and 0.444, respectively. Synthesis was done by heating the autoclave reactor at 100°C for 24 hours. The final products are prussian blue solid material. Sample analysis was performed to examine the properties of the final product. First, SEM analyis was performed and the microstructure of bipyramide crystal was observed. This structure is resembles the HKUST-1. XRD test also confirms that all the samples have peaks at around 6.70°, 9.48°, and 11.62° that is unique for HKUST-1. Additional process, i.e. heating process is done on one of the samples as the representative of the others (sample B) to examine if there is remaining solvent that is trapped. Not all samples are checked for activation process because all samples show similarities during SEM and XRD test. Sample B is then heated at 29°C (B1), 75°C (B2), 115°C (B3), 155° (B4), and 170°C (B5), respectively. The result from SEM and XRD test showed that sample B1, B2, B3, B4, and B5 could endure additional heating process and the remaining solvent that is trapped on the pore is succesfuly removed. Another test is BET adsorption measurement. The measurement concludes that samples A, B, and C are fall within microporous material category because they have pore diameter less than 2 nm and the pore diameter is getting smaller as the DMF volume fraction increases. Specific pore volume and specific surface area calculation also reveal that samples tend to have higher specific pore volume and specific surface area when DMF volume fraction increases. From the result of this experiment it can be concluded that DMF volume fraction has significant impact in controlling the properties of HKUST-1 that is produced during solvothermal synthesis process.

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Journal ID : TRKU-08-11-2021-11499
Total View : 446

Title : The Influence of Wind Speed on the Performance of a Darrieus Wind Turbine

Abstract :

The dynamic load resistance of the Darrieus type wind turbine to changeable wind speed is investigated in this study, and the value of the force received by the wind turbine blades is calculated. Using Autodesk Inventor Professional 2019 software, the analysis was done quantitatively. The Darrieus turbine was tested at 2.5 m/s with a force value of 0.195 N, 3.5 m/s with a force value of 0.274 N, 4.5 m/s with a force value of 0.352 N, and 5.5 m/s with a force rating of 0.430 N. From the simulation results using the Autodesk Inventor Pro 2019 software, the effect of gravitational force is greater than the wind force in, so stress analysis is mainly caused by gravity while the wind force has no significant impact. The simulation results also have a characteristic that the higher the wind speed, the lower the stress value. In addition to the dynamic load simulation, the author also tries to implement the Darrieus wind turbines. The wind turbine blade rotation will be faster, and the Wind Generator will produce a greater voltage if it is supported by sufficient wind speed.

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