Improved 2-D Median Filter For On-Line Impulse Noise Suppression.

An improved 2-D median filter employing multishell concept to suppress impulse noise, is presented

Serial digital communication systems with signals arranged in orthogonal sets

The investigation is concerned with signal design and detection processes suitable for use in a synchronous serial baseband data-transmission system where the signals are transmitted in orthogonal groups over a channel which is time invariant and known. A number of different detection processes have been proposed and analysed theoretically for the case where no signal processing is carried out at the transmitter. Adjacent groups of transmitted signal-elements are here separated by gaps of no signal, whose duration is such that the corresponding received groups of signal-elements do not overlap in time. The detection of a group of signals, in the proposed arrangements, is carried out iteratively by a sequence of similar operations which can be performed successively by a simple piece of equipment. [Continues.

Effect of Two Different Superstrate Layers on Bismuth titanate (BiT) array antennas

The microwave industry has shown increasing interest in electronic ceramic material (ECM) due to its advantages, such as light weight, low cost, low loss, and high dielectric strength. In this paper, simple antennas covered by superstrate layers for 2.30 GHz to 2.50 GHz are proposed. The antennas are compact and have the capability of producing high performance in terms of gain, directivity, and radiation efficiency. Bismuth titanate with high dielectric constant of 21, was utilized as the ECM, while the superstrate layers chosen included a split ring resonator and dielectric material. The superstrate layers were designed for some improvement in the performance of directivity, gain, and return loss. The proposed antennas were simulated and fabricated. The results obtained were small antennas that possess high gain and high directivity with 3606, omni-directional signal transmission that resonant types of conventional dipole antenna cannot achieve. The gain of the antenna with the superstrate layer was enhanced by about 1 dBi over the antenna without a superstrate layer at 2.40 GHz

The relationship between self-esteem and learning reading and writing in sixth graders in the Hashemite Kingdom of Jordan) العلاقة بين تقدير الذات وتعلم القراءة والكتابة لدى طلاب الصف السادس الإبتدائي في المملكة الأردني ة الهاشمية

This study aims at investigating self-esteem relationship with learning reading and writing in sixth graders in public schools in the Hashemite kingdom of Jordan. This major goal includes the following items: identifying the level of self-esteem in sixth graders attending public schools at the Hashemite kingdom of Jordan, identifying their level of reading and writing, identifying the relationship between their level of self-esteem and their learning reading and writing. The population of the study includes all six-graders in public schools in Jordan, whereas multi-stages random sampling is used to choose the sample. This sample consists of 852 students, 460 males and 392 females. The following tools are used: Copper smith’s self-esteem questionnaire, reading and writing achievement test prepared by the researcher. The study has found out that the mean of self-esteem is average )3448(, the mean of learning reading and writing is above average )11492(.The study has also indicated a significant positive correlation between self-esteem and learning reading and writing )44154( which is statistically significant at (0.01). In light of these results, the researchers have recommended that self-esteem affects learners’ academic achievement. Therefore, teachers should improve their students’ self-esteem, encourage them, reinforce their positive behavior, and vary their educational activities to avoid routine and mechanical procedures. This helps students appreciate their efforts. Researchers have also recommended making programs for improving students’ self-esteem. Other recommendations include conducting more studies about self-esteem, learning reading and writing, and achievement in students belonging to different educational stages whether younger or older than those in this study

Reactive Power Imbalance Method for Islanding Detection in Micro-Grid Operation

Micro-grids usage among consumers has become a new attraction due their several of advantage. Its major function is to ensure the stable operation during the fault and a variety of utility grid disruption. Since the utilization of micro-grid become common, the correct application and operation of micro-grid is importance and significant. One of the main challenges in micro-grids operation is islanding detection methods. There are several methods that are handles the islanding detection that each one have advantage and some disadvantage. This paper presents and investigates the Reactive Power Imbalance Method for islanding detection. The passive algorithm implements in this paper due to the low cost operation, however it got the higher non-detection zone (NDZ) and slower response time compare some active methods. The micro-grid simulation is modeled in Matlab/Simulink program and the results of the monitoring are discussed as well. As the result, the performance of the Reactive Power Imbalance method for the islanding detection state is compared with the simulation model without control algorithm. Finally, the micro-grid model capability with control algorithm is shown in order to meet the load demand

Mutagenic properties of modified hydrothermal nanotitania extract

Backgrounds: The mutagenic properties of modified hydrothermal nanotitania extract were carried out using the Ames test (genotoxicity). Materials and methods: The Ames test was performed on Salmonella strains (TA98, TA100, TA1535, TA1537 and TA 102) which contain mutations in several genes with and without S9 metabolic activation from rat liver using the standard assay. The materials were extracted in distilled water and the serial dilutions of concentration ranging from 313 to 5000 μg/mL were used after the incubation period of 24 h at 37° C. Results: These results suggested that all tested concentrations of the material extracts did not produce mutagenic effect in all the strains tested. Conclusions: Findings from this study showed that the modified hydrothermal nanotitania extract was non-mutagenic under present conditions

Development Of A DC To DC Buck Converter For Photovoltaic Application Utilizing Peripheral Interface Controller

Nowadays, renewable energy has become one of the important energy resources in our daily lives. One of the important and promising renewable energy resource today is the photovoltaic (PV). However, weather changes contribute to the PV output power fluctuations. Thus, for a PV-related system, a closed-loop control system is necessary for ensuring the system produces a regulated dc output voltage. This paper presents the development of PIC16F877A microcontroller-based dc to dc buck converter. This converter steps down a dc voltage source to a specific voltage which suitable for other specific applications. For the PV output voltage fluctuating from 18V to 12V, the microcontroller generates a pulse-width modulation (PWM) signal accordingly to control the converter switching device MOSFET IRF540, thus regulating the converter output voltage to 12V. The system simulation was carried out in the PROTEUS ISIS Professional software tool. Due to the unavailability of the PV device in this simulation software, a dc voltage source is utilized. This voltage source is varied to emulate the PV output variations. The simulation results show that the controller managed to step-down the voltage source and regulated at 11.98Vdc. The prototype was built and tested in a laboratory for validation. Due to the constrains and limitations of the PV module, an adjustable power supply was used to provide variation of input voltage levels for the buck converter. The experiment results also show that the output voltage is managed to be regulated at 12V. The results signify the efficacy of developed converter control system algorithm

Ce anomaly in I‒type granitic soil from Kuantan, Peninsular Malaysia: retention of zircon in the weathering product

This paper describes the Ce anomaly observed in granitic soil from the humid, tropical area of Kuantan, Pahang, Peninsular Malaysia. Three granite rock soil profiles from Kuantan, were sampled and all samples were analysed for rare earth elements. All the profiles of the granitic soil samples show prominent positive Ce anomalies, with the Ce/Ce* ratio values (Ce/Ce*= CeN/√LaN.PrN) ranging from 1.2 to 125. l. Ce4+ is compatible in zircon because it has also the same charge and a similar ionic radius as to Zr4+ (Ce4+ = 0.97 Å; Zr4+ = 0.84 Å). The retention of zircon in the weathering product of the granitic rocks will increase the Ce content in the soil. Thus it is likely that the positive Ce anomaly in the REE profile of the Kuantan Granites may also have resulted from retention of zircon in the weathering product