Open Access Short Research Article

Study on the Impact of Lead Sidewall Solder Coverage and Corner Lead Size on Joint Reliability

Jefferson Talledo

Journal of Engineering Research and Reports, Page 62-69
DOI: 10.9734/jerr/2021/v20i417295

Solder joint reliability is very important to ensure that an integrated circuit (IC) semiconductor package is functional within its intended life span as the solder joint establishes electrical connection between the IC and the printed circuit board (PCB). Solder fatigue failure or crack under thermal cycling is one of the common problems with board-mounted packages. There are several factors or package characteristics that have impact on solder fatigue life like package size and material properties of the package components. This paper presents a thermo-mechanical modeling of a leadframe-based semiconductor package to study the impact of lead sidewall solder coverage and corner lead size on the solder joint reliability. Finite element analysis (FEA) technique was used to calculate the solder life considering 50% and 100% package lead sidewall solder coverage as well as smaller and larger critical corner leads of the package. The results of the analysis showed that higher lead sidewall solder coverage and larger lead could significantly increase solder life. Therefore, ensuring lead sidewall solder wettability to have higher solder coverage is beneficial. The study also reveals that packages with side wettable flanks are not only enabling high speed automated optical inspection required for the automotive industry, but they are also providing improved solder joint reliability.

Open Access Short Research Article

Study of Gas-solid-solid Three-phase Flow in Non-Powered Separator

Weiyi Huang, Jinfa Shi, Jie Yang, Junxu Ma

Journal of Engineering Research and Reports, Page 98-105
DOI: 10.9734/jerr/2021/v20i417299

The non-powered separator is one of the key equipment in the dry sand production line, which is responsible for the separation of coarse and fine materials. In this paper, based on the turbulence Standard  Model, the air sand powder three-phase fluid model is simplified to gas-solid-solid three-phase flow, and the 3D model of the non-powered separator was built. The process of sand powder separation was simulated by using Fluent software. It is found that the larger the air volume control valve blade angle is, the more sand is removed, and the blade angle can be adjusted in the range of 15° to 60° according to the actual needs in industrial production.

Open Access Original Research Article

A Comparison of Water Quality Indexes for an Inland River

F. A. Kondum, R. T. Iwar, E. T. Kon

Journal of Engineering Research and Reports, Page 1-14
DOI: 10.9734/jerr/2021/v20i417290

The present study assessed water quality parameters and attempts to compare four different Water Quality Indexes (WQIs) for consistency, similarity and reliability in assessing the water quality of river Benue -an inland river- under wet and dry seasons. The results demonstrate that River Benue is continually being polluted in both dry and wet seasons by different sources, particularly domestic sewage and storm runoffs from farmlands. The quality of the water generally exceeded physiochemical and microbiological infection risk limits recommended in water quality guidelines concerning their use for domestic, recreational and irrigational purposes. Proper sewage treatment and river quality monitoring are needed to guard against hazards to public health and vulnerable river water resources. The WQIs applied were: CCME WQI, BC WQI, Dinius’ WQI and Weighted Arithmetic WQI. To evaluate the differences between these indexes, data on ten water quality parameters (Temperature, pH, total dissolved solids, electrical conductivity, Nitrates, Phosphates, biochemical oxygen demand, dissolved oxygen and faecal coliform count) for two distinct seasons from 6 river monitoring sites along the river Benue at Makurdi reach, were used. Significant discrepancies were observed in classification results between the Dinius’ WQI and the other three WQIs. Similarly, the WA and BC WQIs showed an over-optimistic rating due to their eclipsing limitation. Among others, it was concluded that any of the four indexes except Dinius’ index can be adopted but the CCME water quality index would be best suited for assessing water quality in River Benue.

Open Access Original Research Article

Statistical Analysis on Shear Strength Parameter from Index Properties of Fine-grained Soils

Tariku Tafari Bakala, Emer Tucay Quezon, Mohammed Yasin

Journal of Engineering Research and Reports, Page 15-28
DOI: 10.9734/jerr/2021/v20i417291

Shear strength is the essential engineering property of soil required to analyze and design foundations, retaining walls, bridges, embankment, and related infrastructure. The laboratory equipment and field instruments are not sufficient in developing countries to obtain soil engineering properties, especially strength properties. Thus, Geotechnical engineers usually endeavor to develop statistical models that best fit a particular area and soil type, especially for analysis and design purposes. In this research, a Statistical Analysis on the Shear Strength parameter from the Index Properties of Fine-Grained Soils was studied. For predicting the undrained shear strength parameter, single linear regression (SLR) and multiple linear regressions (MLR) analyses were developed. To develop the intended statistical models for a study, SAS JMP Pro 13, SPSS v22, and Microsoft Excel-2013 software were introduced. The results of a  study indicated that undrained shear strength(Cu) was significantly correlated with liquid limit(LL), plastic limit(PL), bulk density (ρbulk), dry density(ρdry), natural moisture content(NMC), and plasticity index(PI). While it was not significantly correlated with a specific gravity (Gs) and liquidity index (LI) of study area soil. Finally, a strong Model of Cu with a coefficient of determination (R2 = 0.806), good significance level, and less Std. error was obtained from multiple linear regression (MLR) analysis. The developed model can figure undrained shear strength parameter and wide application in the construction industry to minimize the cost, effort, and time for laboratory tests of shear strength parameter of a study area.

Open Access Original Research Article

Cast Iron Cooling Rate Variation Using Cooling Channels: A Numerical Approach

Olumide Adewole Towoju

Journal of Engineering Research and Reports, Page 29-35
DOI: 10.9734/jerr/2021/v20i417292

The cooling rate of molten cast iron can make or mar it. The cooling rate plays a significant role in the resulting mechanical properties of cast iron. It determines the grain growth and size. The mechanical properties of cast iron variation along its length are achieved either with the use of different mold materials or by sectioning to ensure varied cooling rates. Mechanical properties can, however, also be varied along its length without any of these adopted methods by the incorporation of cooling channels in the mould. This study seeks to expand the frontier of this concept with the use of different cooling fluids and fluid flow rate, and numerically investigate the impact on the cooling rate of gray cast iron (class 40). The cooling curve for the cast iron was impacted by the use of different cooling fluids with the attainment of the desired mechanical properties with the selection of an appropriate cooling fluid. Also, the flow rate of the cooling fluid has an impact on the cast iron cooling rate.

Open Access Original Research Article

Synthesis and Characterization of Polyaluminum Ferric Chloride (PAFC) Coagulant with Superior Turbidity Removal Capacity from K-feldspar/NaOH Extraction Residues

Meron Tesfagergish, Alphonse Haragirimana, Na Li, Zhaoxia Hu, Shouwen Chen

Journal of Engineering Research and Reports, Page 36-49
DOI: 10.9734/jerr/2021/v20i417293

The aim of this work was to synthesize polyaluminum ferric chloride coagulant with significant coagulation performance employing K-feldspar/NaOH leaching residue as precursor. Potassium extraction from K-feldspar through sodium hydroxide calcination method is carried out at optimum, activation temperature, time, mass ratio of NaOH to K-feldspar ore in a muffle furnace followed by deionized water conventional leaching. The extraction residues are engaged in co-polymerization of aluminum and iron for the synthesis of polyaluminum ferric chloride (PAFC). The favorable conditions, concentration of hydrochloric acid, hydrochloric acid to residue ratio (v/m), temperature, time and pH are comprehensively investigated. Main process conditions for K extraction are: ore particle mass ratio of NaOH/ore 1.5:1, calcination temperature at 500 °C, and calcination duration of 2 hours, which all jointly yielded an extraction of 95% potassium, whereas polyaluminum ferric chloride (PAFC) synthesis favorable conditions are: HCl concentration of 5M, HCl/residue 5.5:1(v/m), time 2 hours, temperature 100 ℃ and pH 7. 99.8% turbidity elimination efficacy from an initial turbidity of 125 NTU kaolin suspension is obtained. The XRD study is implemented for raw ore, slag and leach residue and proved existing all possible structural changes occurred in extraction routes, additionally FTIR and ICP-MS employed in investigation of polyaluminum ferric chloride (PAFC) to reveal the functional group configuration within the elements of a coagulant and component analysis respectively.

Open Access Original Research Article

Application of Machine Learning (ML) for Enhancing the Transient Performance of Thermal Energy Storage (TES) Platforms Using Radial Basis Function (RBF)

N. Shettigar, M. Truong, A. Thyagarajan, A. Bamido, Debjyoti Banerjee

Journal of Engineering Research and Reports, Page 70-84
DOI: 10.9734/jerr/2021/v20i417296

Thermal energy storage (TES) can be utilized as supplemental platforms for improving operational reliability and systemic efficiency in variety of industries, such as for reducing water usage in power production (food-energy-water/ FEW nexus), chemical and agro-process industries and for improving sustainability (e.g., desalination), etc. Phase change materials (PCMs) can be used in TES due to their high latent heat storage capacity during phase transformation. Inorganic PCMs typically have the highest latent heat capacity and are attractive for their ability to store the larger quantities of thermal energy in small form factors while conferring respectable power ratings (however, they suffer from compromised reliability issues, that often arise from the need for subcooling). Subcooling (also known as supercooling) is a phenomenon where the temperature needs to be reduced substantially below the melting point to initiate solidification. A technique for obviating subcooling issues is to allow a small portion of the PCM to remain un-melted. This allows the PCM to initiate nucleation from the un-melted portion of PCM (this is termed as the “cold finger” technique). Thus, reliability is enhanced at the expense of substantial reduction in storage capacity. A fundamental challenge for using this technique is the inability to reliably predict and control the amount of melt fraction in the total volume of the PCM (such that a target amount of the PCM remains solidified or un-melted at the end of each melt-cycle during repeated melting and solidification of the total mass of PCM). However, using Machine Learning (ML) techniques, this deficiency can be addressed by reliably predicting and thus controlling the amount of melt fraction in the total volume of the PCM with a higher accuracy than conventional techniques (such as using multi-physics-based models or numerical solvers). Conventional techniques for predicting transient characteristics in real time control schemes typically leverage multi-physics-based models that are often effective only for a narrow range of operating conditions with concomitant disadvantages: they are highly sensitive to small variations in the measurement uncertainties and are therefore susceptible to large levels of error in the real time predictions (and are unreliable for implementation in diverse range of operating conditions). In this pioneering study, nearest neighbor search processes (such as radial basis functions) were utilized along with machine learning (ML) algorithm using a training data set to predict the PCM melt fraction and to demonstrate the feasibility (and efficacy) of this approach. This technique is simple to implement and is device independent as well as robust (i.e., it can be deployed successfully even under conditions where the sensors malfunction, such as thermocouples that are off-calibration). This technique was demonstrated successfully for predicting the melt fraction of a PCM with high accuracy and robustness. With this method, the melt fraction of a PCM can be accurately determined, which allows the maximum thermal capacity of a PCM to be utilized while mitigating reliability issues (such as subcooling) and enhancing the thermodynamic efficiencies of the TES platforms. Melting experiments were performed using a digital camera (for video recording) and a graduated cylinder containing PCM for monitoring the transient values of the melt fraction based on the height of the liquid phase of the PCM in the cylinder. An array of 3 thermocouples was mounted at specific heights within the body of the PCM to monitor the temperature transients at these specific location during the propagation of the melt front within the PCM. In the final stages of the melting process, the predictions from the ML algorithm was found to be more accurate (90~95% accuracy) than that of the conventional techniques based on physics-based solvers (~60% accuracy). The accuracy of the ML algorithm was low at smaller melt fractions (~30%) and improved substantially at higher melt fractions (~95%). Furthermore, the accomplishments of this study display the feasibility of a RBF ML method which can be implemented for the accurate prediction and control of a real world stochastic system which can exhibit nonlinear and chaotic dynamics which change over time.

Open Access Original Research Article

Mitigating Wire Short Defect on LGA Device through Substrate Design Optimization

J. Pulido, R. Rodriguez, F. R. Gomez, E. Graycochea Jr.

Journal of Engineering Research and Reports, Page 85-88
DOI: 10.9734/jerr/2021/v20i417297

During new product development of a substrate land grid array (LGA) device, issues were encountered at wirebonding process due to design constraints. This paper is focused on addressing the wire-to-wire short defect during wirebonding process of the first bond. Wirebond process optimization was comprehensively employed, but eventually recommended to have a substrate redesign with relocated bond fingers to increase the wire angle (less steep) between the first bond and the second bond. With the improvement done in the substrate design and through wirebond process optimization, wire-to-wire short defect occurrence was successfully eliminated.

Open Access Original Research Article

Dynamic Analysis of Fatigue Life Prediction on the Shafts of a Modern Cassava Peeling Machine for Safe and Economic Use

Pondi Pius Eddy, Nwigbo Solomon Chuka, Obende Eziekel Omeiza, Olisakwe Henry Chukwuemeka, Chikelu Okechukwu Peter, Azaka Onyemazuwa Andrew

Journal of Engineering Research and Reports, Page 117-130
DOI: 10.9734/jerr/2021/v20i417301

The durability of a machine structure is based on its mechanical performance through its entire service life. To avoid structural failures in machines, it is a standard design practice that machines be analyzed based on the types of loading (static and fatigue) associated with it in order to design safe and dependable machine structures. These types of analyses are performed with the purpose of estimating the behavior of the mechanical parts under specific operational conditions. The aim of this research is to investigate the effect of different loading to the maximum load on the redesigned shafts of an existing cassava peeling machine capable of peeling at least one (10) tons of   cassava tubers with different weight, size or shape per day  to ascertain the effects on the bending moment, shear force, deflection angle, shear stress and bending stress, and evaluate if there is need to reduce or increase the thickness of the shafts to a standard considered to be safe and economical. The three shafts of the cassava peeling machine have been carefully analyzed to check for their fatigue life under different loading conditions. From the analysis, with stress values of 48.640MPa, 49.1289MPa, 3.06089MPa and shaft diameter values of 34.6799mm, 34.7955mm, 13.7941mm evaluated from the reduced stress diagrams and ideal diameter diagrams for abrasive cylinder shaft, peeling cylinder shaft, and retainer shaft respectively, gave positive results because none of stress values were greater than reduced stresses (calculated stress value from Tresca’s theory) on the respective shafts. Therefore, a standard steel shaft of 35mm diameter is appropriate for manufacturing of the machine and also safe and economical.

Open Access Original Research Article

Concept Design of a Portable Carrot Seeder

Marvin T. Valentin, Alex Smeets, Daniel E. Ciolkosz, Algirdas Jasinskas, Milagros B. Onalan, Alvin C. Dulay, Leonardo D. Dumalhin, Constantino T. Sudaypan Sr., Stanley F. Anongos Jr., Cheryll C. Launio, Marlon N. Galad, Roger Lee M. Suclad, Keithler M. Pagnas

Journal of Engineering Research and Reports, Page 131-141
DOI: 10.9734/jerr/2021/v20i417302

A concept design of a carrot seeder, filed for patent application, was successfully developed in this study. Farmers were visited and interviewed and the data regarding their existing practices in planting carrots, corresponding tools and equipment and planting requirements such as hill spacing, row spacing and plant bed size were gathered. These data were used as input in the preparation and simulation of the seeder design with the aid of Solidworks software.

The seeder consisted of seed metering assembly, frame, ground wheels, skid, handle, power transmission, furrow opener and seed covering mechanism. It has 5 metering discs and the spacing between rows is adjustable. The metering disc is provided with grooves on its periphery of size that can accommodate 2 to 5 carrot seeds. Draft force to push the device in usage is 10 kg-force. The designed overall weight is 12 kg.

Open Access Original Research Article

Addressing Delamination through Advanced Semiconductor Die Design

Rennier S. Rodriguez, Frederick Ray I. Gomez

Journal of Engineering Research and Reports, Page 142-146
DOI: 10.9734/jerr/2021/v20i417303

Innovations and breakthroughs are continuously driven in semiconductor manufacturing to overcome existing assembly limitations and recurring difficulties. This paper is focused on the resolution of the delamination issue during die attach assembly process. A new design of semiconductor die is presented to establish a robust adhesion or interface bonding between the silicon die and the epoxy material for die attach. The paper also provides the specialized design of manufacturing flow for the improved die design through advanced wafer fabrication method and wafer cutting technique. The realization of the advanced silicon die design would ultimately mitigate the delamination issue and would contribute for a robust die attach assembly process.

Open Access Original Research Article

Die Attach Curing Program Automation of N2 Parameter for Process Robustness

Jerome Dinglasan, Rogel Dela Rosa, Frederick Ray Gomez

Journal of Engineering Research and Reports, Page 147-152
DOI: 10.9734/jerr/2021/v20i417304

In the world of semiconductor industry, automation plays a big role on every manufacturing plants to improve efficiency, prevent product yield losses, and making sure that top quality products will be delivered on end user. On die attach curing process of manufacturing semiconductor integrated circuits (IC) devices, certain problems occur like wrong Nitrogen (N2) parameter setting on the oven curing machine, with human intervention during setup, causing leadframe oxidation related defects. The paper discussed the importance of automation system on processing semiconductor IC products on die attach curing process, eliminating mostly human intervention on setting up machine parameters, storing and managing programs, restrict unauthorize users from accessing, provide friendly user procedures to prevent human errors and prevent oxidation related defects.

Open Access Review Article

Review of Neural Network Algorithm and its Application in Temperature Control of Distillation Tower

Ningrui Zhao, Jinwei Lu

Journal of Engineering Research and Reports, Page 50-61
DOI: 10.9734/jerr/2021/v20i417294

Distillation process is a complex process of conduction, mass transfer and heat conduction, which is mainly manifested as follows: The mechanism is complex and changeable with uncertainty; the process is multivariate and strong coupling; the system is nonlinear, hysteresis and time-varying. Therefore, traditional control methods are difficult to accurately control, but neural networks can greatly improve this problem. This article introduces the basic concepts of distillation tower temperature control, comprehensively introduces the application of various neural network algorithms in distillation tower temperature control, and compares their advantages and disadvantages and their effect. At present, there are many researches on neural network control of distillation tower temperature. The methods are different and each has its own merits. This article has carried out a systematic review to provide reference for the development of related industries.

Open Access Review Article

Mathematical Modelling of Surface-Groundwater Interactions under Varying Hydrological Conditions: Review of Past Works

Jyoti Chetan Vanikar, Rajeev Kumar Bansal, Vineeta Basotia

Journal of Engineering Research and Reports, Page 89-97
DOI: 10.9734/jerr/2021/v20i417298

Surface-groundwater interaction is a research area of significant importance for its central role in wastewater treatment, irrigation, drainage, flood control, erosion and sediment control. Mathematical models are often used for the estimation of surface-groundwater interactions under the variety of hydrological conditions. Due to cost effectiveness and ability to accommodate variations in aquifer parameters, mathematical models have gained immense importance in the past few decades. The objective of this review paper is to portray the contribution of the hydrologist towards the growing area of surface-ground water interaction from all over the world who proposed, analyzed, executed and validated the developed Mathematical models. To begin with, we briefly introduce the main mathematical equations that govern the flow of groundwater in unconfined and confined aquifer systems. The development of stream-aquifer models is presented in a chronological order to provide a clear understanding of the contributions of past works. The methodology used in the past work is adequately discussed without going into mathematical details. Furthermore, we also summarize recent developments concerning groundwater flow in presence of vertical streambed, partial penetration, stream-stage variations and multiple recharge/discharge basins.

Open Access Review Article

Factorial Design of Concrete Production in Hot and Warm Humid Zones in South East Nigeria

M. Odoanyanwu Ndubuisi, H. Ivoke Ifeanyichukwu, C. Odom Uzodimma

Journal of Engineering Research and Reports, Page 106-116
DOI: 10.9734/jerr/2021/v20i417300

This study narrates the quality of concrete production as slump wet in warm and hot zones. The quality of concrete mixture is of inevitable concern to all stakeholders in the construction industry in the zones when the climatic conditions of the zones are considered. Absence of National standards, environmental and climatic conditions and other factors are the main factors that affect the quality of concrete produced in the area. The affected mix ratio is examined and all the prevailing construction/production practices are considered. All necessary measures for improving the quality of concrete produced are surveyed considering the relationships between various variables used in the mixture. Three major factors (variables) that are found to be influencing the quality of concrete in the south east, Nigeria. The absence or lack of implementing the existing building code, climatic conditions in the zones and types of construction materials available, all remain the major variable influencing the quality of present concrete production in the zones of south east, Nigeria.