The Effect of Heat Shocks and Freezing–Thawing Cycles on the Mechanical Properties of Natural Building Stones

The damage to rock masses due to the action of freezing is one of the most important factors in the development of landscapes, the performance of civil structures, and the efficiency of mining operations. In this research paper, the effect has been studied on the physical and mechanical performance of seven different natural building rock samples. The testing program included an experimental study on both dry and saturated intact rock samples and therefore, the effect of saturation on the extent of damage on the tested samples has been discussed as well. Based on the obtained results, freezing–thawing cycles increase the porosity of rock samples and decrease the values of P-wave velocity, uniaxial compressive strength, elastic modulus, and Brazilian tensile strength. Moreover, the behavior of different rock types differs to some extent when exposed to weathering cycles under dry and saturated conditions. A multivariate linear regression analysis was used to predict the changes in the physical and mechanical properties of different rock types. It was been shown that with some cautions, the obtained correlations can be generalized for practical cases and can be used to predict the change of rock physical and mechanical properties during the lifetime of rock engineering projects. Such predictions have a high potential of applicability in quite different types of natural stone applications in cold climates. From the stability of structures created in rock materials to the durability of structures created by different natural stones.

An Improved Clustering Using by Likely Attributable Function and Informed Selection in WSN for Science of Management and Engineering

Wireless sensors networks (WSNs) are traditionally composed of large number of tiny homogenous sensors nodes connected through a wireless network that gather data to be treated locally or relayed to the sink node through multi-hop wireless transmission. The low-energy adaptive clustering hierarchy (LEACH) protocol is one of the Famous protocols used in the wireless sensor networks (WSNs). The LEACH protocol in wireless sensor network suffers from many Bugs and many researchers proposed different methods to mitigate them. In this paper, we propose two ideas in a format for improving leach protocol. For Cluster head selection we used a Likely Attributable Function that in this function used from a factor. This factor that we called the informed selection factor helps to farther nodes not selection for cluster head. This significantly decreases the energy consumption and increases the lifetime of associated nodes. Simulation is conducted in using MATLAB results are analyzed for energy consumption.

A Comprehensive Study on Safety of New Energy Vehicles

New energy vehicles (NEVs) have become a fundamental part of transportation system. Performance of an NEV is hugely determined by batteries, motors, and embedded electric control units. In this paper, a comprehensive study that covers all these key components is presented. Mechanisms and characterizations of failures are given in detail. On top of these, algorithms for fault diagnosis are established based on big data of real-world NEVs with joint considerations of design flaws, usage behaviors, and environmental conditions. In this way, multiple types of faults can be detected ahead of time to avoid accident. Proposed methods have been verified by real-world operational data, indicating effectiveness while providing insights for NEV design optimization.

Investigation of Hybrid Composite Properties Fabricated from Bagasse Fibers Reinforced with Al2O3 and SiC for Light Weight Applications

The primary purpose of this study was to investigate mechanical properties of hybrid composite fabricated from bagasse fibers reinforced with Al2O3 and SiC for automotive purposes. The technique applied was referred to as the hand layup technique for the fabrication of composite. The experiment was conducted based on Taguchi L9 orthogonal array design. Data shows that the maximum tensile and flexural strength were 39.9 and 56.1 MPa respectively. Hardness and impact strength were 75.05 HV and 14 J respectively. The results indicated that the increasing Al2O3 and SiC wt.% increase the tensile strength and after bagasse fiber wt.% reaches optimum values the tensile strength decreased. Increasing Al2O3 wt.%, increases flexural strength and after bagasse fiber and SiC wt.% reaches optimum values, flexural strength was decreased. Increasing bagasse fiber wt.% increases the hardness of composite, and increasing Al2O3 and SiC wt.% increases the hardness, then after reaching optimum values the hardness was decreased. Increasing Al2O3 wt.% after the optimum values decrease the impact strength, and increasing bagasse fiber and SiC wt.% increase impact strength. The developed hybrid composite material was found to be improved the properties of composites after addition of Al2O3 and SiC powder as filler materials. This thesis recommends higher institutes, automotive companies, manufacturing companies, the construction sector and the government to conduct on how to utilize this abundant waste of bagasse fiber resource.

Design and Control Strategy of Bio-inspired Underwater Vehicle with Flexible Propulsor

Biomimetics aims to take inspiration from nature and develop new models and efficient systems for a sustainable future. Bioinspired underwater robotics help develop future submarines that will navigate through the water using flexible propulsor. This research has focused on the Manta Ray species as batoid has a unique advantage over other species. This study also aims to improve AUV (Autonomous Underwater Vehicle) efficiency through biomimetic design, the purpose of which is to observe and study the marine environment, be it for sea exploration or navigation. The design and prototyping process of bioinspired AUVs have been mentioned in this study, along with testing a propulsive mechanism for efficient swimming and turning capabilities. The Robot was designed taking structural considerations from the actual Manta-Ray locomotion and body design. The propulsion mechanism and control circuit were then implemented on the developed systems. The prototype of the Manta Ray was able to generate a realistic swimming pattern and was tested in an acrylic tank. The experimental results obtained in the tank basin are very close to the results we observe in the real-world scenario in terms of the vehicle's forward and turning motion.

Experimental Investigation on the Advantages of Dry Machining over Wet Machining during Turning of AISI 1020 Steel

In this study, the experiment was conducted to investigate the advantage of dry machining over wet machining during turning of AISI 1020 steel using cemented carbide tool on a CNC lathe machine. Surface roughness and cutting temperature were measured by VOGEL surface roughness tester and infrared thermometer respectively. The experiments were conducted based on Taguchi L9 orthogonal array design. Surface roughness, cutting temperature, tool life, and machining cost were analyzed graphically. The average surface roughness and cutting temperature achieved with wet machining was 2.01 μm and 26.540C, which was 17.41% and 44.86% respectively, lower than dry machining. The high cutting temperature in dry turning result in short tool life, which was 41.15% shorter than wet turning. The machining cost of wet turning was about 56% greater than the cost of dry turning. The cost of coolant in wet turning is 42.88% greater than that of the cutting tools. The highest cost was shared by tool cost, which was 81.33% of the total cost for dry turning, while 70.00% of the total cost was shared by coolant cost for wet turning. Results revealed that dry turning is more economical than wet turning.

Development of a Low Cost Eco-Friendly Minimum Quantity Lubrication System for Machining Processes

Recently all environmental worries are calling for reducing the usage of fluids in machining operations. One of the promising solutions that appeared lately is minimum quantity lubrication (MQL). This research aimed to develop an eco-friendly cooling system for a lathe machine and assess its performance. After considering the customer needs, the needs were translated into engineering specifications in the conceptual design phase, and then the quality function deployment was developed. Three concepts were generated and evaluated considering the selection criteria, and a final concept was selected using the decision matrix method. Following this, a detailed design and fabrication of the subsystems such as the oil tank and a structure accommodate all the components. The developed system was tested on six different workpiece samples to compare the MQL system with the conventional one. In general, the MQL system resulted in lower surface roughness values as well as lower tool wear.

Physics of a Spinning Object Cyclic Inversion at an Orbital Flight

The opening up of space flights is going on with physical discoveries. One of them was a spinning object cyclic inversion revealed on the MIR space station classified in 1985. Later, the NASA International Space Station openly showed the same effect. This physical effect was an object of stare studying by physicists and mathematicians. They developed only approximated and numerical models on the level of assumptions. The inversion of the spinning objects in the condition of free flight is the subject of gyroscope theory. The mass of the spinning object at the orbital flight generates the system of the interrelated inertial torques that results from the action of the inertial torques produced by the curvilinear motion of the object around the earth. This system of the torques acting on the spinning object at an orbital flight manifests its cyclic inversions, which is the gyroscopic effects. The theory of the gyroscopic effects describes the method of application of the system of the inertial torques, the physics of all gyroscopic effects that manifested by any rotating objects under any condition of their motions.

Design and Development of an Electronic Sieving for Sand Separation using Node MCU System

Sand sieving is now considered one of the essential needs in the construction industry. Where businesses collaborate to find the best and highest-quality methods for extracting pure sand suitable for construction. These businesses always require high-quality machines to complete the process flawlessly. This is also to prove its market power and guarantee its products. This research talks about the various mechanisms for designing and manufacturing sand sieving. The sand sieving process expresses the filtering of sand from the rest of the components such as stones or gravel. The literature department studied ten different studies in the design and manufacture of sand sieving machine in different ways. Where these methods vary between using the engine and electricity and using the primitive manual method. After performing these machines several tests and evaluation of the process, it was found that the engine speed affected the energy consumed to sift the sand. Also, the sieve holes are affected by the size of the sifted sand. Where sieves are manufactured in different sizes to suit the size of the sand to be purified. On the other hand, this article contains the future recommendation of the machine to avoid errors and give effective results as needed.

Design Analysis of Vertical Axis Wind Turbine Blade Using Biomimicry

Performance and efficiency of a Vertical Axis Wind Turbine improved by using a modified turbine blade, derived from biological features, by harness more wind energy. The detailed simulations were carried in Q-blade’s X-foil, Java foil and Sim Scale software at low wind speed with bio-mimicable cambered foil add-ons to different biostructure blades such as Maple seed leaf, Eagle wing. Among these simulations, the Corrugated Dragonfly vein FX 63-137 foil shows improved performance over cambered foils and FX 63-37 itself. The Maple-Wing combined blade structure showed an improved lift-drag ratio with a high coefficient of power.