Volume-6, Issue-5, May 2020

Abstract

To improve portability of current gesture recognition technology, this paper proposes a method of the design and implementation of gesture recognition based on embedded system by combining embedded platform with Open CV. Firstly, image denoising using the weighted mean filtering method, and the morphological open operation is used to obtain the complete contour, and the edge extraction is carried out by the improved Canny operator; Secondly, image segmentation using two-dimensional maximum interclass variance. Then analysis and processing of specifies the feature information of gestures images using Hu distance. Finally, the template matching method is used to recognize the gesture image. The experimental results show that the gesture recognition based on embedded system has strong portability, higher recognition rate and easy implementation.

Keywords: Embedded, template matching, human-computer interaction, Hu distance.

References

Keywords: Embedded, template matching, human-computer interaction, Hu distance.

Abstract

This paper reports experimental result of a distance and position measurement method for autonomous movement control of four-rotor helicopters (drones) that uses two spotlights and comparing with a red marker using case, discuss the results of autonomous flight test evaluations. To conduct autonomous drone flights exceeding 10 m under unstable GPS signal situations, such as under bridges or inside tunnels during periodic maintenance inspections, correct self-positioning measurements are indispensable. This study proposes a simple method whereby autonomous drone movement control can be performed over distances exceeding 10 m by using two high-power 100 V alternating current spotlights set on the ground as infrared (IR) light sources. The spotlights are directed at the investigation target, such as the cracked area of a bridge, and the intense light of the two spotlights provides reference points that enable the drone to determine its correct position. In autonomous flight-testing in an enclosed corridor, our method provides capable of determining the drone’s position at distances up to 15 m with a standard deviation of 0.31 m. Our proposed method would be effective in situations where no skilled drone control operator is available and for flights requiring visual cue confirmations under adverse outdoor conditions.

Keywords: Infrared spotlights, Four-rotor helicopter, Long distance measurements, Bridge/tunnel investigations.

References

Keywords: Infrared spotlights, Four-rotor helicopter, Long distance measurements, Bridge/tunnel investigations.

Abstract

The present study focusses on the parametrical investigation of unidirectional and woven carbon fiber double cantilever beams subjected to mode I, in order to study its effects on their strength and failure. Different crack lengths as well as width and thickness of the specimens have been analyzed extensively. The maximum normal and shear stresses are found to decrease as the crack length increases for both types of composites. The crack length directly affects the strength of the specimens. A numerical model was developed using the Comsol Multiphysics to predict the failure of double cantilever beams. The crack initiation and progression in the specimens was predicted using the cohesive zone method (CZM) and the delamination at the interface.

Keywords: fracture toughness, uni-directional, woven fabric, crack propagation, double cantilever beam.

References

Keywords: fracture toughness, uni-directional, woven fabric, crack propagation, double cantilever beam.

Abstract

Tilapia powered vertical aquaponics system (TPVAS) is an effective way to increase crop production in a food desert city per unit rooftop area by extending crop cultivation into the vertical dimension to feed the ever-increasing population of the world and keep the city-pollution free and cooler. Experiments conducted over the years to assess the viability of tilapia powered lettuce, strawberry, water spinach and mint production in the media-based vertical aquaponics system at the rooftop and lab of Bangladesh Agricultural University, Mymensingh, Bangladesh. The wastewater of the tilapia tank irrigated to the 4 feet height and 3-4-inch diameter vertical plastic pipes holding 15 to 18 saplings in each pipe which passing through the coco dust, coco coir, water hyacinth root, and brick chips media then return into the fish tank again. Fish growth performances, nutrients availability, and their use assessed. The mean length and weight gain of tilapia were 2.95 (±0.83) to 11.77 (±2.49) cm and 32.71 (± 9.43) to 170.38 (±78.7) g. The feed conversion ratio (FCR) were 2.5, 2.35, 2.33 and 1.5 and survival rates were 96, 78, 85 and 98.33% for lettuce, strawberry, water spinach and mint based tilapia aquaponics systems. The fish and vegetable production was 30.64 to 135.20 and 12.47 to 123.25 MT/ha/90 to 120 days respectively. Among the four media, coco coir produced the highest crop than the others.Therefore, it is concluded that the TPVAS is suitable and capable of producing fish and vegetables at the rooftop keeping the rooftop cooler and greener than nearby traditional roof gardening buildings.

Keywords: Fish well-being, Rooftop, Safe food, Tilapia, Vertical aquaponics.

References

Keywords: Fish well-being, Rooftop, Safe food, Tilapia, Vertical aquaponics.

Abstract

The article presents the calculation method based on the heat and humidity parameters of the units direct and indirect-evaporative cooling in air conditioning systems in buildings are analyzed various technical diagrams. On the basis of experimental and theoretical studies established the benefits of schemes based on indirect-evaporative cooling. The processes of heat and humidity of air treatment, demonstrate the benefits of solar installations with devices indirect evaporative-type compared to conventional solutions.

Keywords: Climate, Air, Compressor, Rotating Heat Exchanger, Irrigation Chamber, Solar Energy, Solar Installation

References

Keywords: Climate, Air, Compressor, Rotating Heat Exchanger, Irrigation Chamber, Solar Energy, Solar Installation