A non-invasive air-coupled v-type ultrasonic leak detection system

New method for non-attached ultrasound PVC pipe monitoring is proposed for vibration and pressure leak detection systems. The advantages of this method is that it can provide a quick and accurate means of detecting leakage in between each pair of sensors while transmitting results wirelessly. The selected PVC pipeline aims to present an example to fill the fundamental gap for monitoring the plastic water pipelines. The monitoring system is a modified V-type ultrasonic air-coupled and a redesign of circuitry to bring low power consumption to 2.5mw in full functionality. The operation is tested and verified in laboratory in which the system is able to recognize leakage up to 0.4mm in diameter with 94.97% accuracy even for water pressure (less than 1 bar). System alarming is also designed in a way to ignore pipe vibration as a result of changes in pressure and reduce false error significantly

Non-invasive application for domestic pipeline monitoring and corrosion detection

In this paper a method of assessment and control of condition for domestic pipelines is proposed and been tested for a pair. Most of the previous works has been designed for long range pipes as they may carry valuable liquids. But having a system to monitor domestic’s pipes also can help to save so much time and energy in future as leaking itself can be destructive in structures. This system is applying much lower frequency (40 kHz) in compare to other similar systems (above hundreds megahertz) which leads to lower power consumption. This ultrasonic wave is applied to short distance pipes to observe the changes and detect the leakage base on adjusted thresholds amplitude. It is able to detect smallest changes as the matter of difference in acoustic waves for healthy and damaged pipes. The alarming system works by analyzing output signals from receivers. Ultrasonic sensors are having 40 kHz central frequency for both transmitter and receiver with best responsibility at face to face condition. Acoustic sensors are working independently in pair and by dismissing one pair others will not affect continuity of data acquisition. For this paper a couple of transducer (a transmitter and receiver) operation has been investigated. By understanding the functionality of a pair can analyse show they are working in more numbers. This system is a cheap, easy to assemble, install and maintain for homes and most of public facilities such as schools, hospitals, parks, offices and business buildings. It doesn’t need any particular constriction or changes in pipeline structures

A new technique to reproduced high-dynamic-range images for low-dynamic-range display

Tone mapping is a process for reproduction of High-Dynamic-Range images (HDR) for Low-Dynamic-Range (LDR) output devices. In this report, author presents a new local tone-mapping operator, derived from the Contrast Limited Adaptive histogram Equalization (CLAHE) technique for displaying high dynamic range image. The CLAHE is a method which was originally developed for medical imaging. This method has effectively expanded the full dynamic range of display and it is fully automatic. Due to different luminance intervals could result in overlapped reaction on the limited response in limited response range of visual system, scene region splitting and merging were used to segment the scaled luminance and perform the image segmentation to segment image into smaller part. After the region splitting and merging, there will be some noise or variation of intensity that may result in holes or over segmentation. As the result, the morphological operation, opening and closing were used to perform the mask to applied different clip limit of the CLAHE operation

A local tone mapping operator for high dynamic range images

In this paper, we present a new tonemapping operator to display high dynamic range image onto conventional displayable devices and printers. In our work, a new tone map algorithm, derived from the Contrast Limited Adaptive histogram Equalization (CLAHE) technique is presented. Due to different luminance intervals could result in overlapped reaction on the limited response in limited response range of visual system, we use scenes region splitting and merging to segment the scaled luminance, L(x, y) and perform the CLAHE in each segment with different clip limit in order to extending our visual response range to cope with the full dynamic range of high contrast. Until now, there is no fix standard of objective evaluation available to measuring the quality of displayed High Dynamic Range (HDR) images because it is difficult to know how the light or dark the image should be displayed to faithful to the original HDR image. As the result, the main evaluation is based on human's subjective evaluation. In this paper, we consider this to evaluate the performances with different tone mapping method

Soil moisture sensor and read-out circuit topology for large array deployment.

This paper focuses on the analysis of a BJT based soil moisture sensor that outputs a voltage corresponding to the change in soil resistance. The measured sensor’s sensitivity is 51.1mV/% with a deviation of 19.7mV from sensor to sensor. The deviation which is more than twice smaller than the sensitivity suggests that it is suitable to be used in a large array to detect gravimetric moisture in individual soil samples. Integration of read-out circuitry to the sensor shows that an array operation of the sensor is possible and can be used to aid in moisture detection in fertigation farms

Investigation of TiO2/graphene nanocomposite based photoanode in dye-sensitized solar cell

Dye-Sensitized Solar Cell (DSSC) which is the third generation photovoltaic solar cell is a promising low cost solar cell. This type of solar cell is robust and do not require clean environment for fabrication. This paper focuses on implementation of graphene in the DSSC photoanode to improve the electron path from photoanode to FTO transparent electrode. In this research, N719 synthetic dye is used as synthesizer and three different types of graphene nanopowder namely 8 nm flakes, multilayer flakes and nanoplatelets were implemented in titanium dioxide as photo-anode. I-V measurement was done under illumination of 1000 W/m2 using solar simulator and the results show that the DSSC with titanium dioxide photoanode doped with graphene multilayer flakes performs the best in term of open circuit voltage (0.782 V), short circuit current density (12.408 mA/cm2) and energy conversion efficiency (4.4%)

Tuberculosis bacteria counting using watershed segmentation technique

Tuberculosis (TB) is the second biggest killer disease after HIV. Therefore, early detection is vital to prevent its outbreak. This paper looked at an automated TB bacteria counting using Image Processing technique and Matlab Graphical User Interface (GUI) for analysing the results. The image processing algorithms used in this project involved Image Acquisition, Image Pre-processing and Image Segmentation. In order to separate any overlap between the TB bacteria, Watershed Segmentation techniques was proposed and implemented. There are two techniques in Watershed Segmentation which is Watershed Distance Transform Segmentation and Marker Based Watershed Segmentation. Marker Based Watershed Segmentation had 81.08 % accuracy compared with Distance Transform with an accuracy of 59.06%. These accuracies were benchmarked with manual inspection. It was observed that Distance Transform Watershed Segmentation has disadvantages over segmentation and produce inaccurate results. Automatic counting of TB bacteria algorithms have also been proven to be less time consuming, contains less human error and consumes less man-power

Design of front end of a RF receiver

Radio frequency (RF) circuit is having a rapid growth in wireless telecommunication. The increasing demand for higher quality and popularity of wireless services have urged the development of low cost multi-functional and reconfigurable RF front end modules fabricated from advanced device technologies. The RF front end is generally defined as everything between antenna and the intermediate frequency (IF) stage. For a receiver, this "between" area in eludes filter, low noise amplifier, mixer and local oscillator. The circuit was designed based on CMOS 0.18 um technology to input a 2. 5 GHz RF signal and local oscillation of 2.25 GHz. This results in an output IF frequency of 250 MHz. The RF front end circuit had been simulated using Advanced Design System to obtain the proper output frequency and determining the system performance

Statistical optimisation of process parameters on the efficiency of N-TiO2 dye sensitised solar cell using response surface methodology (RSM)

In this study, nitrogen doped titanium dioxide-based dye-sensitised solar cell was successfully fabricated using screen printing technique to discover the optimisation of process parameters for the solar cell efficiency using response surface methodology (RSM). Parameter optimisation has been a major concern in solar cell fabrication. The selected parameters were: nitrogen concentration (15-25 mg of urea), the film thickness (25-60 µm) and dye loading time (12-24 hours), the optimum condition which yields the highest efficiency of 3.5% was at 15 mg nitrogen concentration, 25 µm film thickness and 24-hours dye loading time. Film thickness was found to have a significant influence on efficiency while the loading time exceeding 18 hours has the least significant effect

Timing generator for 120fps CMOS image sensors on 0.13 μm CMOS technology

Image clarity is an important criterion in digital imaging. However, typical rolling shutter type complementary metal-oxide semiconductor (CMOS) image sensors with frame rate of 30fps which is used for relatively slow speed image capture suffers from image blur phenomena when capturing the fast-moving objects. Therefore, an integrating chip control circuit is needed for a high frame rate shift registers structure readout control circuit to overcome the image blur phenomena suffered by rolling shutter readout scheme. In this paper, a timing generator acts as the control circuit for 120fps CMOS image sensors on 0.13μm CMOS technology is developed. The design is modeled and analyzed using ModelSim for FPGA verification and post layout validation is successfully demonstrated with Synopsys EDA tool. The on-chip timing generator design block results in total power consumption of 4.0733μW and total design area of 61.64 χ 60.64 μm2