Global Journal of Researches in Engineering

This paper proposes a generalised feed-forward artificial neural network model that fulfils the failure prediction of a three phase 5.8MW, 11 kV Slip-Ring SAG Mill Induction Motor at Goldfields Ghana Limited, Damang Mine. It provides a general understanding of three phase induction motors,faults associated with induction motors and also emphasizes the use of intelligent systems, particularly artificial neural network, a modern failure prediction technology of induction motors. Site analysis and motor data (Current, Power and Winding Temperatures) collection were conducted at the Damang Mine. Simulation results are presented using MATLAB software (2017a) package to develop the fault prediction model. The proposed feed-forward neural network used the Levenberg-Marquardt and Bayesian Regularisation in training.

Purpose: Exposure to space radiation may place astronauts at significant health risks. This is an under-investigated area of research and therefore more knowledge is needed to better plan long-term space missions. The purpose of this study was to assess the effect of radiation on murine naïve and activated T lymphocytes (T cells) and to test the effectiveness of thermal, radiation and flight tracking technology in biological scientific payloads. We cultured cells in specific cytokines known to increase their viability and exposed them to either flight or had them as ground controls. Flight cells were kept under proper environmental conditions by using an active thermal system, whereas the levels of radiation were measured by NASA’s Timepix radiation sensor during ascent, cruise at 60,000 feet, and descent. In addition, an Automatic Dependent Surveillance Broadcast (ADS-B) device was utilized to track the state vector of the aircraft during flight.

To comprehensively analyze the seismic performance and failure modes of edge joint, which is composed of T-shaped concrete-filled steel tubular column and H-shaped steel beam, the joint was imposed through low frequency cycling loading. Model of edge joint was established by the nonlinear finite element software ABAQUS. The effect of different parameters, such as axial compression ratio and side plate extension length, on the seismic performance were simulated. The results indicates that the buckling of the steel beam occurs at the lateral extension of the side plate due to the strengthening of the side plate; the axial compression ratio has no obvious effect on the ultimate load; the increase of the side plate length can effectively improve the ultimate load.

This paper describes a high-resolution analog acceleration and vibration amplifier for use with piezoelectric polyvinylidene fluoride (PVDF) sensors. The purpose of this system is to monitor automated parts placement on integrated circuit boards. One of the problems facing production and inspection equipment is the occurrence of resonant and ambient vibrations. Even small errors can cause systems with micrometer and nanometer precision to exceed design tolerances. This work describes a method to monitor mechanical vibrations through a portable and inexpensive signal-processing unit. The system provides user-selectable gain and filtering modules that are compact and reliable. PVDF is currently used in sensing applications, and its material properties have proven very useful for sensing mechanical stress, strain, pressure, and temperature.

Ten years have passed since the Great East Japan Earthquake and the subsequent accident at the Fukushima Daiichi nuclear power plant (NPP) that occurred on March 11, 2011. The earthquake and tsunami caused significant loss of lives and widespread disaster in Japan. Several reports have been published on the nuclear accident; however, the original data released at the beginning of the accident were written in Japanese, and some of these documents are no longer accessible. Some of the scenarios pertaining to the accident have become standardized theories, and these scenarios may be passed down to future generations with different descriptions, which may not fully describe the actual occurrences. To prevent future nuclear accidents, the accident at Fukushima Daiichi must be properly understood and analyzed.

The delimitation and delimitation of the water rounds has been an environmental determinant of great importance in the instruments of territorial planning, however there have been no effective criteria when it comes to delimiting and aligning the water rounds, that is why in the present study, The normative review of the delimitation of riparian zones in Latin America and Colombia was carried out, from which it was found that the guidelines issued by the Ministry of the Environment have not been efficient for the delimitation of said areas, therefore it is considered important that the Ministry of the Environment should Reconsider said rule, if it is the case that it is considered that the delimitation of the water sources would be categorized according to the width of the channel, the slope of the land and the strategic ecosystem in which they are found.

The cost ratio of steel to concrete exceeding 100 in most of the RCC structures, alternative materials for replacing steel are underway to develop a sustainable built environment. Bamboo has been in housing industry since time memorial as a standalone structural member for lighter loads of roofing and wall cladding units. It has been tested for its use as reinforcement in OPC based cement concrete structures replacing steel reinforcement with appreciable performance while requiring serious attention on serviceability and durational aspects. The alkali activated low calcium fly ash & slag-based concrete with steel reinforcement as structural components cured at ambient temperature (RGPC) are being popularized in the most consumed sector of concrete construction industry.

This study analyzes and model zone-wise earthquakes inter-event recurrence interval (IRIs) using a stochastic Weibull probabilistic distribution model. The study region between 19–28◦N and 72–84◦E up to 200 km peripheral boundaries of Central India (Madhya Pradesh) is divided into four zones (Zone South, West, North, and East), respectively, based on different clusters of earthquakes with shared seismo-tectonic regimes. Seismic events’ catalog from different national and international resources for a period of more than 100 years are considered in this study. The seismic data is grouped into two categories based on a different range of earthquake magnitudes (3≤Mw< 4 & 4 ≤ Mw≤ 6). Zone-wise results are produced in the form of hazard curves and conditional probabilities of occurrence for a range of elapsed time from 3 to 30 years from last recorded earthquakes in various zones.

Aircraft attendants are at a high risk of occupational injuries and illnesses, leading to substantial compensation costs and staff shortages in the aviation industry. To address this issue, this study introduces an innovative virtual reality technique and advanced motion tracking system integrated with ergonomics tools to effectively evaluate the risk of musculoskeletal disorders (MSDs) among aircraft attendants during their routine tasks. The study involved twenty-two participants who performed two common tasks: opening/closing the passenger door,and lifting luggage from the floor and placing it into the overhead compartment. The inappropriate postures were identified, which resulted in excessive strain on the participants’ lower back. By analyzing the impact of biomechanical variables, such as object weight, body height, and trunk motion, on the lower back, the study provides valuable insights that can inform the development of safety training programs and real-time monitoring approaches for injury prevention. Additionally, this innovative technology can be applied to other occupational fields.

In wind energy conversion system, extraction of optimum power and efficient operation are two major challenges. In grid connected mode, a doubly fed induction generator (DFIG) control unit is designed to operate at optimum speed to deliver maximum output power in the grid while the voltage, frequency and harmonic regulations need to be fulfilled. Vector control associated with proportional-integral (PI) controllers has been widely applied in wind farms for reliable power regulation of DFIG. As DFIG based wind energy conversion system (WECS) experiences strong nonlinearity and uncertainties originated from the aerodynamics of the wind turbine and magnetic saturation of the generator, different adaptive and nonlinear control schemes have been proposed to resolve the problems associated with fixed-gain PI controllers.

The work in this paper deals with reconstructing and optimizing the wing geometry of an Unmanned Combat Aerial Vehicle for improved performance and reviewing the impact of the modification on flight parameters in a steady flight. The behavior of airfoils at planned flight conditions under I.S.A. is checked in XFLR5 software. Following up by 2-D CFD and boundary layer analysis of former and new airfoil, dimensions of the wing are re-developed, keeping the fuselage and tail structure same. The existing wing and the optimized wing design is analyzed by Vortex Lattice Method and Triangular Panel Method, with an objective to make the shape of the wing aerodynamically suitable for an increased Lift to Drag ratio and thereby minimizing drag coefficients.

This paper shows the effect of different bleaching agent on whiteness index and bursting strength of the cotton knitted fabric. Bleaching process uses three types of bleaching agents namely hydrogen peroxide (H2O2), sodium hypochlorite (NaOCl) and calcium hypochlorite Ca(OCl)2 with varying their concentration and these are 1.5 g/l, 2.5 g/l, 3.5 g/l, 4.5 g/l, and 5.5 g/l. In the same time, scouring agent was caustic soda, and its concentration for all the bleaching agents was same. It is obvious that with the increase of bleaching agent concentration, whiteness index increases, and bursting strength reduces.

Actually New Innovation Green Concepts for future World Ecology Air Transportation Technologies will be focusing to new Optimal Geometry Structures as the complex Integral Disc-Wing Adaptive Transforming Frames for any Passenger Hybrid Electrical Aircraft and Solar Disc Airship with more Efficiency Active Vortex Energy Systems. The new International R&D European Programs to the Aircraft Vision’2035/40 are consist the innovation Design Science MAI Results and Patents for participation during 2020/23 to joint EC Research Consortium IMOTHEP and FUTPRINT50 of Hybrid Electrical Power of the Regional Aircraft for the Low Toxic and Low Noise Air Transport Operation Worldwide as recovery initiatives after COVID-19 Destroy pressure to the International Airlines and Consortiums new priority Low Cost Efficiency and Commercial Strategy.

This article describes alternate methodology for determining heat transfer correlations from experimental programs. In conventional methodology, the form of heat transfer correlations is determined before the experiment by deduction, and the experiment is performed in order to quantify constants in the deduced correlation form. In the proposed alternate methodology, the form of heat transfer correlations is determined after the experiment by induction. Three examples in the text apply the alternate methodology to data in the literature, and compare the resultant correlations to widely accepted correlations based on conventional methodology and the same data. The correlations that result from the alternate methodology agree with the underlying data much more accurately than correlations that result from conventional methodology. The difference in accuracy reflects the fact that deduction is much more difficult than induction, and therefore much more likely to include errors, and less likely to accurately describe the underlying data.

This study investigates different chassis designs through a simulation-based design approach. The inherent aluminum ductility and softness could make chassis a daunting modification if not analyzed properly. Structural finite element analysis is comprehensively performed on a vehicle chassis for static loading cases up to 1G in equivalent acceleration. The analysis of the vehicle chassis of both A36 steel and 6061 aluminum for the scenarios of bump, front impact, side impact and a rollover. The von Mises stresses and displacement results showed that the steel chassis possessed higher safety factor in all load cases. The safety factors for an aluminum clone of the steel chassis in some load cases are below 1.0, hence indicating that the failure criterion has been triggered and failure would occur under the 1G load. The original aluminum chassis deformation is far more severe than steel reaching as high as 9.88 mm for the bump loading. A modified aluminum chassis is proposed, by optimizing the wall thickness of the rectangular bars. The slight increase in weight resulted in overcoming the deficiency of aluminum in load carrying capacity. An evaluation matrix procedure is implemented to analyze the trade offs between cost, weight and safety factor for the three chassis materials.

In this paper a detailed analysis of breakout resistance of a horizontally laid anchor plate in sandy soil is presented. To compute the distribution of soil reactive pressure on the failure surface, Kötter’s equation is employed. The failure surface is assumed to be in the form of a cone. An analytical expression for the breakout resistance is derived. Results are reported in terms of the breakout factors and net breakout resistance. A comparison is made with the available experimental data and theoretical solutions.

The garments industries which are traditionally operated are facing lots of problems such as low productivity, poor line balancing, high rejection, high defects, unable to achieve lead time. So defects minimization is the first condition of reducing cost and increasing productivity. The work aims to minimize the defect percentage by using DMAIC approach of Six Sigma methodology. The study is carried out in Ananta Apparels Ltd. by using DMAIC methodology of six sigma to minimize the defect rate in sewing section. Five phases of the DMAIC methodology named Define, Measure, Analyze, Improveand Control which indicates some critical defects such as stain, skip stitch, broken stitch, and slip out in the sewing section of Ananta Apparels Ltd. We applied various types of six sigma tools in different phases. The outcome of this study is very significant to implement in the sewing section of the apparel industry.

It is found from literature on impact of changes in climate and the resultant rise in sea level, that the scenarios, which are presumed for estimating the rise in Sea Level are stranded on a lot of doubts. Projections by different teams of scientists and real time data from IPCC's predictions do not always match and mostly rather differ. Various models so far considered, grounded on mathematical and statistical methods are anticipated to experience unforeseen variation due to the present unpredictable behaviour of the ice sheets. Studies about the contribution from Antarctica itself towards rise in Sea Level predicts abrupt variations in different projections and accordingly the importance of detailed study on Marine Ice Instability has been highlighted in this paper. The phenomenon related to MISI and MICI has been stressed upon to arrive at more correct projections on Sea Level Rise in coming decades and centuries.

Demand response (DR) is one of the major stakeholders in the smart grid and has been used as an energy reconciler between supply and demand. After a literature overview, the importance of the paper is enhanced by having a theoretical and behavioral-based analysis of DR in power systems. In this work, the potential factors that influence more DR among customers and the residential market as a whole have been discussed. The customers’ elastic demand approach can pave the way for adapting a responsive demand mechanism that ensures the system reliability and cost effective measures. Alternatively, this approach can make the program more effective and supportive in serving the social welfare as whole.

In recent years, in the cooling technology for high-power electronic devices such as power transistors used for drive motor control of electric vehicles and hybrid vehicles, a method of flowing a cooling fluid to a cooling substrate having a fin structure has become the main technology. The structure of the cooling fluid flow path is a channel flow through multiple narrow plate gaps to secure a heat transfer area. In this study, the heat transfer characteristics when the aspect ratio of the channel having a flat rectangular cross-section was changed were investigated in detail by experiments. Moreover, the difference in the heat transfer characteristic at the time of making a rectangular flow path into vertical installation and horizontal installation was also investigated.

While robust optimization techniques have been found useful for the modeling of uncertainties in a wide range of fields, their application to concurrent engineering optimization models have been limited. This research introduces new integer, non-linear programs for the robust concurrent design of product families and their corresponding assembly systems. The models introduced involve the application of interval and ellipsoidal uncertainty functions to the solution of the latter problem. A new, exhaustive search algorithm for the determination of exact solutions to the models is also introduced. The implementation of the model is demonstrated with an example.

Purpose: The main aim of this paper is to develop a new mathematical model for the mixed model two-sided assembly line balancing problem (MTALBP) generally occurs in plants producing large-sized high-volume products such as buses or trucks. Methodology: In this paper, the proposed mathematical model is applied to solve two-sided mixed-model assembly line balancing problem with lower and upper bound. The proposed mathematical model is solved using a branch and bound algorithm on LINGO 17.0 solver. Findings: Based on the computational result, line efficiency that is obtained by reducing single and mated stations of the assembly line is good as compare to the theoretical minimum number of stations and reduces computational time by applying boundary conditions. Practical implications: Since the problem is well known as an NP-hard problem a benchmark study problem is solved,and the result of the study can be beneficial for assembly of the mixed model products in term of minimizing mated stations as well as computational time. Originality: By literature review, t his paper is first to address mixed-model two-sided assembly line balancing problem with bounds using the exact solution approach.

In this paper, Weibull and Poisson distribution calculation are carried out with new data to conclude a conclusion are they suitable for circuit breakers remaining useful life assessment (RUL). Old data are covering a 10 years period consisting of measured voltage drop on CB contacts and number of tripped short circuit faults. In this paper, new data, from the last 3 years, would be used to make a comparison with old data and make conclusions have been probability distributions correctly chosen.

The research team at ERAU and UTHSCSA analyzed the effects of suborbital flight stressors and various light conditions (red, white, no light) on the Arthrospira platensis (Spirulina), onboard Blue Origin’s New Shepard vehicle. Commercially available cyanobacterium species were cultivated and closely monitored in mother colonies several months before the suborbital flight mission. The aim of this study was to estimate the biomass production and growth as a potential dietary alternative for prospective human spaceflight's life support system. Spirulina samples were flown in a NanoLab with adjacent avionics supporting the light conditions and sensors to monitor the temperature, relative humidity, and accelerations. The various flight parameters measured in the NanoLab were validated with the flight data gathered by Nanoracks, the flight integrator. Thus, we also assessed the effect of microgravity and different light conditions on the gene expression. Our data indicates that the Spirulina samples onboard the rocket had significant (p < 0.01-0.0001) downregulation of majority of the gene expression.

A trainable analog restricted Hopfield Network is presented in this paper. It consists of two layers of nodes, visible and hidden nodes, connected by weighted directional paths forming a bipartite graph with no intralayer connection. An energy or Lyapunov function was derived to show that the proposed network will converge to stable states. The proposed network can be trained using either the modified SPSA or BPTT algorithms to ensure that all the weights are symmetric. Simulation results show that the presence of hidden nodes increases the network’s memory capacity. Using EXOR as an example, the network can be trained to be a dynamic classifier. Using A, U, T, S as training characters, the network was trained to be an associative memory. Simulation results show that the network can perform perfect re-creation of noisy images. Its recreation performance has higher noise tolerance than the standard Hopfield Network and the Restricted Boltzmann Machine. Simulation results also illustrate the importance of feedback iteration in implementing associative memory to re-create from noisy images.