Papers by Keyword: Filter

Abstract: The study is devoted to solving the actual problem of determining optimal filter configuration parameters that ensure the maximum protective service life of dust filters—specifically, the time of use before reaching the critical point when breathing through the filter becomes impossible.The purpose of the work is to determine the configuration coefficient of dust filters (surface area, fold pitch, and fold height), enabling the calculation of the initial pressure drop across the filters.To identify the correlation between the configuration parameters of dust filters, a 3D model of a filter cartridge with overall dimensions of 100×50×15 mm – matching the standard sizes of most commonly used filter box designs – has been fabricated. Polypropylene filtering material with a fiber packing density of 50 g/m² and fiber diameters ranging from 1 to 3 µm has been used; the thickness of the filtering layer was 2 mm. Sets of five filter samples have been produced with varying filtration areas, which depended on the number of folds, ranging from 5 to 30. To measure the pressure drop across the filters, a specialized test stand complying with EN 13274-3:2001 «Respiratory protective devices – Methods of test – Part 3: Determination of breathing resistance» has been employed, under constant airflow rates of 30 dm3/min and 95 dm³/min.The relationship between the pressure drop across pleated filters and parameters such as filtration area, pleat channel width, and filter height has been established, allowing the determination of a configuration coefficient that ensures minimal resistance to airflow. For rectangular filters from polypropylene material with a fiber packing density of 50 g/m² and a filtering layer thickness of 0.6 mm, a pleat height of 10 mm, the optimal spacing between pleats has been found to lie within the range of 3–4 mm, corresponding to 2.5–3.3 pleats per cm. For calculating the configuration coefficient of filters made from materials with varying fiber packing densities the algorithm has been proposed. The algorithm includes determining the initial pressure drop of a flat filter, calculating the filter area based on specified pleat spacing (W) and height, defining the configuration coefficient, and comparing it with the recommended optimal value.The scientific novelty lies in establishing an experimental relationship between the pressure drop and the configuration coefficient of pleated filters. This relationship enables the identification of optimal parameters for filtration area and the ratio of the distance between pleats to their height.The value of this research consists in the development of an algorithm for determining the configuration coefficient of pleated filters, which allows for a more accurate estimation of the initial pressure drop.

Abstract: This investigation was carried out in a lab setting with the aid of a filter set. This study aimed to lower the level of clean water contamination and assess the filter media's performance in Fitu Village, Ternate City, using physical and chemical criteria. Temperature, turbidity, total dissolved solids (TDS), and odour are physical parameters. While pH, Mn (manganese), and Fe (iron) are the chemical parameters. Sand-activated carbon made of silica and zeolite is the filter medium. One hundred eighty litres of water from a resident's well make up the sample. The physical characteristics, namely the TDS of 1250 mg/L, the turbidity of 27 NTU, and the temperature of 25 °C, show the outcomes of investigating healthy water as raw water in the Kelurahan Fitu. Fe concentration was 1.3 mg/L, Mn concentration was 0.6 mg/L, and pH was 9. Water is passed via silica sand, zeolite, and activated carbon filters before entering the filter after further inspection. According to the results, the TDS has dropped to 897 mg/L, the turbidity has changed to 24, and the temperature is 24 °C. The filtered water meets the chemical standards for Fe concentration with only 0.91 mg/L of Fe, 0.45 mg/L of Mn, and a pH of 7.9. According to the study's findings, inhabitants of Fitu Village in Ternate City can efficiently reduce pollutants and metal levels in their healthy water by employing a filtering system that uses silica sand filter media, zeolite, and activated carbon.

Abstract: This study aims to obtain a better contrast in the film image on X-ray examination of the ossa manus in posteroanterior projection with the addition of an acrylic compensating filter. An investigation was carried out using the phantom manus object on the Quantum CS-2 X-ray apparatus in the examination room 1 of the Margono Soekarjo Hospital (RSMS) by adding acrylic material on the outside of the collimator with a thickness ranging from 2 mm to 22 mm as a determinant of the thickness of the compensation filter. The radiographs were processed by a CR reader and imported into the Weasis software version 2.0.7 to analyze their pixel values. The results showed different compensatory filter thicknesses in the carpal and distal phalanges. An acrylic compensation filter with a thickness of 2.32 cm was considered optimal to compensate for the distal phalanges area and 0.08 cm for the carpal area in the phantom manus with an exposure factor of 55 kV and five mAs.

Abstract: With the development in the technologies and modern equipment the level of the pollution has increased significantly. Air pollution caused due to the factories and the automobiles contributes a large share in this pollution and also one of the most challenging because the Particulate matters are released directly in to the air. So, this project is based on solving the global problem of air pollution by designing an air purifier that brings the increased level of air pollution to its lowest level. In this air purifier HEPA filters is used to purify the air and to make it smart sensors and IOTs are used. To make this whole process automatic Arduino based microcontroller (Node MCU ESP12e) is used which makes this whole system self-operating .This model will also use air quality sensor (MQ135 ),temperature sensor (DHT11) and humidity sensor (DHT11) for its working. Along-with this for energy requirements solar panels are used but for future scope electricity generation using piezo-electric plates has also been suggested.

Abstract: We study in this work, the occurrence of defects modes in the transmission spectrum and the band structure of a perfect photonic asymmetric serial loops structure (ASLS) utilized for narrow-band filtering. The perfect structure presents large photonic bandgaps that result from the modes of the loops resonances and the system periodicity. Besides that, the existence of defects within this perfect ASLS, whether at the segment or loop level, or both of them, causes the appearance of two, three, or four defect modes within gaps with good transmission rates and high-quality factors. These defects modes are extremely sensitive to changes in structural parameters. This system can be used to filter or guide the incoming electromagnetic waves. The interface response theory has been used to accomplish the analytical calculation. Green's function of the full system is determinated using this method. It allows us to calculate the dispersion relation and the transmission rate. Therefore, this paper can provide ideas for the design of multi-channel tunable filter using for frequency division multiplexing and microwave and signal processing.

Abstract: The article discusses the technologies used in the manufacture of liquid rocket engines filter elements. The analysis of the most widely used methods in the aerospace industry for obtaining grooves and holes in metal filters is carried out, as well as progressive methods for their production are proposed. Special means of technological equipment for the fine filter elements manufacture using electroerosion treatment have been developed.

Abstract: The cardiac signal is very important for the heart disease diagnosis and evaluation. The noise cancelation represent one of the most preprocessing step in ECG signal processing, usually, this signal is very sensitive and varies with time. The ECG signal is mostly contaminated by different signals like Power line noise signal, Baseline signal and muscle signal. The power line interference signal is the most effected signal on the ECG during data recording. Several papers try to cancel the noise based on different ways and to extract the useful information. In this paper a novel approach based on stone blind source extraction is used to extract the pure ECG signal from raw ECG, the main advantage of the proposed approach compared with the classical technique is to separate all the useful information without filtering or cancelling the suitable data from the recording signal. Real ECG data from MIT-BIH databases is taken and the MATLAB program is used to evaluate the experimental results. The performance of the proposed approach is measured based on SNR and MSE. The main contribution of this paper is to use Stone blind source separation technique as a first time in ECG signal analysis and prove that this method is the best technique compared with conventional ways. The obtained result proves Stone BSS technique is very efficient to remove the power line noise.

Abstract: In the article the dependence of protective efficiency of the respiratory protective devices on the filter penetration coefficient and leakage of the polluted air through sealing band was established. The leakage was determined by the ratio of the filter resistance and the sealing band. The relationship between increasing the filter resistance and worsening the protective effectiveness of respiratory protective device was established. Factors that worsen the respirator quality were determined: the gaps between the face and half-mask, weak tension of the head harness. Filter parameters that will ensure high efficiency for respirators of the second protection class were established.

Abstract: A periodic microstructure with dielectric and metal layers is proposed to obtain a bandpass filter. The multilayer microstructure is compounded of ring cross slot and cross slot. The center frequency of the filter is 0.338THz with a 3dB bandwidth of 75.62GHz. The maximum insertion loss in the pass band reaches 0.60dB. The bandedge transitions of the rejection bands are 232dB/THz and 176dB/THz, respectively. Furthermore, the physical mechanism of near field distribution and the influence of two factors (the number of metal layer and dielectric layer) on the passband have been studied. Meanwhile, the frequency response is analyzed for different incident angles and polarizations. The frequency response characteristic is insensitive to the polarization, and a good performance for incident angle of the transmission is obtained. It can be applied to THz atmospheric communication system.

Abstract: A design and simulation for microstrip line filter with semicircle defected ground structure has been researched. In this paper, simulated soft (Ansoft HFSS V.6.0) used to be simulated the frequency response under different parameters such as dimensions, amounts of SDGS.The results show good performance of SDGS in high cut-off frequency, erase of harmonic frequency, smaller dimension. Final, a filter with4.4GHz center frequency,high Q-factor had been design and fabricated.