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Axial fans are often used in cooling electronic enclosures where low noise levels are highly demanded. Therefore, methods for predicting the noise emitted by an application including single or multiple fans are desirable to improve, stimulate and reduce the cost of low-noise design. The prediction of sound generated from fluid flow has been difficult due to the non-linear form of the governing equations,...
Accurate rainfall estimation from radar reflectivity is crucial in hydrological modeling and quantitative precipitation estimation. Various rainfall intensities exhibited by different rainfall drop size distribution contribute to reflectivity and rain rate relationship (Z-R) variability in radar rainfall estimation. This paper focuses to evaluate the Z-R model during the massive flood in December...
Forced convection cooling systems utilize fans which can be axial or radial, small or large in many different configurations. Efficiency of a fan depends on its electrical and mechanical designs as well as the environmental conditions that the fan is exposed to. Typically, the overall efficiency of an axial fan varies between 15 to 40 percent. Power losses may be due to electrical, aerodynamic or...
Dynamic stability is an important consideration for an underwater glider because its slow motion makes it susceptible to underwater currents. This is compounded by its weak propulsion system whereby it self-propels by shifting its net buoyancy either positive or negative during forward motion. In this paper, steady state Computational Fluid Dynamic (CFD) simulation was used to evaluate the dynamic...
The performance analysis of reflectarray resonant elements based on Finite Integral Method is presented in this work for 5G antenna systems. Reflection loss, bandwidth and linear phase range of square and circular resonant element configurations have been investigated at 15 GHz and 20 GHz frequencies. Periodic reflectarrays consisting of 5×5 elements have been designed at 20 GHz for both elements...
This article presents a design procedure of phase controlled linear adaptive array antenna operating at 38GHz for 5G application. The Wilkinson equal power divider/combiner feeding network is loaded with the antenna elements for equal power distribution. The Obtained gain of the antenna is 12dBi at the operating frequency of 38GHz. −15dB of isolation is observed between the array antenna elements...
This paper investigates the interdigitated electrode design for impedance spectroscopy technique targeting lard detection purposes. Two types of interdigitated electrode were designed and evaluated on high precision impedance converter board subjected to frequency range of 5kHz to 100 kHz. Samples of lard and beef tallow were extracted and mixed with hexane solvent for different concentration levels...
Basically, plastic surgery procedure introduces skin texture variations between images of the same person (intra-face) thereby making recognition more difficult than in normal scenario. Since the shape of significant face features such as eyes, nose, eyebrow and mouth remains unchanged even after plastic surgery, edge-based recognition methods can be employed. This paper employs an edge-based Gabor...
In this paper, an illumination normalization technique for edge-based face recognition on face images with non-uniform illumination conditions, is proposed. The proposed illumination normalization technique fuses the merits of color (Red, Green and Blue) normalization (Nrgb) and gamma correction (GC) for color images. By the fusion of these methods the image becomes independent of the change in face...
The amount of light is an important issue in several scenarios ranging from scenic design, light pollution study, robots navigation, occupational health and safety, illumination engineering, agriculture, medical appliances and many more. It is typically determined by using an illumination meter. The meter, also known as lux meter is used to measure the density of light in an area which measured in...
The present study examines the effects of partial slip bearing configuration on improvement in load capacity and reduction in friction coefficient for journal bearing lubricated with couple stress fluids. The couple stresses effects are analyzed based on Stokes micro-continuum theory and partial slip configuration is analyzed using Navier slip boundary conditions. The nondimensional pressure and shear...
Task assignments to team of homogenous autonomous robots are in research trends in robotic field. Autonomous homogeneous multi-robot is known to have similar architecture in terms of structure and identical control system as well as their tasking. At present, most research of multi-robot mainly focuses on motion control layer. Nevertheless, a successful control and coordination of a group of robot...
Properties of substrate material play an important role in the design of reflectarray antenna. In this work linear and non-linear dielectric properties of substrate materials are discussed thoroughly. Rogers RT/d 5880 and K-15 nematic are used as linear and non-linear dielectric materials respectively, to design different reflectarray resonant elements in X-band frequency range. Simulated and measured...
A planar microwave absorber based on the anisotropic properties of tunable reflectarray has been introduced in this paper. A non-linear liquid crystal material along with polystyrene foam has been designed to analyze X-band microwave absorption performance of three different reflectarray resonant elements. A thorough investigation based on finite integral method has been performed to investigate the...
Float-over installation method has been recently used to install topsides onto jacket type of platform. As a viable alternative to the traditional lifting installation method, this method uses a float-over barge to transport and install topsides onto the platform by ballasting operations. This method eliminates the use of heavy lift vessel, and thus is economical for a platform with heavy topsides...
Single-crystal germanium-on-insulator (GOI) structures are essential to integrate high-speed transistors, high-efficiency solar cells, and non-volatile spintronic memories on a panel, because GOI structures can be used as templates for epitaxial growth of multi-functional materials, as well as channel layers with high-carrier mobility. We investigate formation of high-density nanostructured single...
Reflectarray antennas provide a low cost, low volume and low profile way for different type of applications but due to limited phase ranges and high reflection loss performance their use is limited in the field of satellite and earth observatory systems. In this paper a rectangular patch reflectarray operating at 10 GHz constructed on 1mm thick isotropic and anisotropic substrates is proposed to be...
In this paper, a new approach in predicting the hardness of Titanium Aluminum Nitrite (TiAlN) coatings using hybrid RSM-fuzzy model is implemented. TiAlN coatings are usually used in high-speed machining due to its excellent surface hardness and wear resistance. The TiAlN coatings were produced using Physical Vapor Deposition (PVD) magnetron sputtering process. A statistical design of experiment called...
This work investigates the suitability of a flexible Minkowski-like pre-fractal antenna (MLPF) for application in the Very High Frequency (VHF) Land and Mobile Radio (LMR) frequency bands (136-174 MHz). The proposed center-fed, third iteration antenna has been manufactured using both copper tape and Shield It Super, a conductive textile. It has been tested on four types of ground plane, i.e. rectangular,...
This work investigates the design of a flexible Minkowski fractal antenna. Two potential materials are included for examination - conductive copper tape and ShieldIt conductive textile. Both are designed and simulated to achieve a satisfactory resonance at the Very High Frequency (VHF) band for Land Mobile Radio (LMR) application through proper structure segmentation and iteration. Optimization concludes...
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