Engineering Commons^™

Study On The Thermal Distortion, Hardness, And Microstructure Of St 37 Steel Plate Joined Using Fcaw, Maijuansyah Maijuansyah, Yanuar Rohmat Aji Pradana, Gaguk Jatisukamto, Solichin Solichin

Journal of Mechanical Engineering Science and Technology (JMEST)

This study sets out to investigate the distortion angle, microstructure, and hardness of St 37 steel plate weld joint produced by FCAW using the welding current of 80, 110, and 140 A. By using flat position, CO2 and E71T-1 wire were utilized as a shielding gas and electrode filler, respectively. The distortion angle measurement was done on 3 different locations of the welded sample perpendicular to weld direction by using bevel protractor. The micro Vickers tests were then applied gradually at the crosssectional surface with a distance of 0, 5, 10 and 15 mm from weld centerline using the load …

Comparison Study Of Mechanical Properties Of Al-Si Alloy With And Without Nanoreinforce Iron Oxide (Fe2o3), Cepi Yazirin, Poppy Puspitasari, Muhamad Fatikul Arif

Journal of Mechanical Engineering Science and Technology (JMEST)

Nanoreinforce materials such as ZnO, eggshell, Al2O3, TiO2, and ZrO2 have been shown to improve the mechanical properties of Al-Si alloy. Nanomaterial Fe2O3 has many applications as catalysts reaction in electronic devices, for example, semiconductor materials, paint formulations, lithium rechargeable batteries, and is often applied in industrial fields. It is known that Fe2O3 can be synthesized through the stirring process on machine and method used will involve several steps that relatively take a long time. In this study, Al-Si alloy reinforced by using nanomaterial Fe2O3 which sintered at a temperature of 600C for 3 hours aimed to improve mechanical and …

The Effect Of Chemical Pretreatment Process On Mechanical Properties And Porosity Of Bacterial Cellulose Film, Tito Arif Sutrisno, Heru Suryanto, Retno Wulandari, M. Muhajir, Shikh Mohd Shahrul Nizan Shikh Zahari

Journal of Mechanical Engineering Science and Technology (JMEST)

Bacterial cellulose (BC) is a natural polymer which have superior properties, like high porosity, high purity, and high permeability. The study objective is to determine the influence of chemical pretreatment on tensile strength and the porosity of BC. The method was to make BC films from pineapple peel extract through fermentation process for 14 days. The pretreatment was conducted by immersion of BC in BmimCl, H2O2, and NaOH solution with a concentration of 2.5%; 5%; and 7.5 %, heated at 80 °C then dried in the oven, and the samples were then tested by a tensile test using ASTM-D636-V standard, …

The Characteristic Of Overhang Object To Material Usage On Fdm 3d Printing Technology, Redyarsa Dharma Bintara, Aminnudin Aminnudin, Zumrotul Ida, Ferian Rizki Arbianto, Dani Prasetiyo

Journal of Mechanical Engineering Science and Technology (JMEST)

Fuse Deposition Modeling (FDM) 3D printing is one of additive manufacturing technology which physical 3D model is build up layer by layer. The support structure is almost involved on the process if overhang shape is met on the 3D model. It has main function to prevent the 3D printed model from collapsing. Commonly, the single material source of FDM 3D printer machine is to supply building two structure, structure of main 3D object and support structure. Hence, our goal optimizes the using of support material for reducing the main material usage. Furthermore, the sixteen of variation overhang angle is set …

Elastic Linear Analysis Of Connecting Rods For Single Cylinder Four Stroke Petrol Engines Using Finite Element Method, Didin Zakariya Lubis, Andoko Andoko

Journal of Mechanical Engineering Science and Technology (JMEST)

A connecting rod is one of the most critical parts in engine assembly which transfers energy from the piston to the crankshaft. The connecting rod mainly undergoes tensile and compressive loading under engine cyclic process. The forces acting on the connecting rod are forces due to maximum combustion pressure and forces due to the inertia of the connecting rod. This research aimed to analyze the design of the connecting rod of single-cylinder four-stroke engines. This study used CAD software for modeling and structural design. Stresses generated across all the locations of the connecting rod were evaluated using FEA Software. Elastic …

Third Voices Conference On Teaching Stem With Music, September 22-23, 2019, Lawrence M. Lesser

Journal of Humanistic Mathematics

The third annual VOICES (Virtual Ongoing Interdisciplinary Collaborations on Educating with Song; https://www.causeweb.org/voices/) conference will be held online September 22-23, 2019. Chaired by Tiffany Getty, this conference will explore the use of song to teach STEM (science, technology, engineering, and mathematics) at the postsecondary (or secondary) level.

Special Functions, Bruce F. Mcguffin

Journal of Humanistic Mathematics

A consideration of special functions on esthetic and utilitarian grounds.

The Influence Of Different Packaging Materials And Atmospheric Conditions On The Properties Of Pork Rinds, Kristi Kõrge, Katrin Laos

Journal of Applied Packaging Research

Rancidity development in high fat content products is a common off-flavor flaw in snack foods. Packaging is often used to avoid spoilage and extend shelf-life. The properties of pork rinds packaged in four different packaging materials with and without nitrogen were studied during 120 days of storage (22 °C, RH 60%, absence of light). The influence of different packaging materials and atmospheric conditions on pork rinds’ water activity, hardness, crispness and rancidity development was determined. The PET/PE packaging material had lower barrier properties for the product in both atmospheric conditions compared with PP/metPP (40 and 50 μm) and PET/PETmet/PE. PP/metPP …

Pilot Study: Measuring Attitudes Toward Ramp Resource Management—The Influence Of National Culture, Nadine G. Muecklich, Hans-Joachim K. Ruff-Stahl, Ivan Sikora

Journal of Aviation Technology and Engineering

Ramp resource management (RRM) is a highly flight-safety-relevant, but to date widely overlooked, part of the air transportation system. Organizational, national, professional, and safety cultures play an important role in setting up resource management and training. This pilot study evaluates the influence of national culture on attitudes toward RRM, based on Geert Hofstede’s Values Survey Module. A slightly adapted version of this survey module was distributed to ramp personnel in Germany and national cultural indices were generated. A one-way analysis of variance revealed that, while some influence of national culture in RRM could be concluded, the majority of the results …

False-Match Symmetry: Data Files And Simulation Code, Cherlyn J. Ng, Bart Farell

Biomedical and Chemical Engineering - All Scholarship

This record provides data from random-dot stereograms to use in solving the binocular correspondence problem through false-match symmetry. It also provides an implementation of the algorithm used in the article ‘Solving the stereo correspondence problem with false matches’ [Ng CJ, Farell B (2019) Solving the stereo correspondence problem with false matches. PLoSONE 14(7): e0219052. https://doi.org/10.1371/journal.pone.0219052].

The record consists of two parts, Data and Algorithm Demo. The Data component consists of pre-computed Keplerian arrays of all possible matches between filtered random-dot image pairs containing stereoscopically defined surfaces. The Algorithm Demo allows data files to be computed afresh from supplied pairs of …

Hydrolearn: Facilitating The Development, Adaptation And Sharing Of Active-Learning Resources In Hydrology Education, Emad Habib, Melissa Gallagher, Jenny Byrd, Olivia Lahaye, Cary Rivet, Micah Lacombe, David Tarboton, Scott Black, Dan Ames

Civil and Environmental Engineering Faculty Presentations

Lightning presentation and workshop presented at CUAHSI HydroInformatics Conference, 2019. https://www.cuahsi.org/community/cuahsi-science-meetings/. This workshop is offered for hydrology faculty interested in implementing or adapting active-learning, data-driven resources to their educational settings. The workshop aspires to create faculty networking and development opportunities with the overall goal of promoting and reducing barriers against adoption of active-learning resources in hydrology. The workshop will use the recently developed NSF-sponsored HydroLearn platform, along with resources from CUAHSI, HydroShare and other community platforms, to enable participating faculty to develop and share educational resources. The workshop will showcase existing seed modules and will cover best practices in …

Asymptotic Orthogonal Space Shift Keying In Massive Mimo Systems, Won Mee Jang

Department of Electrical and Computer Engineering: Faculty Publications

We investigate space shift keying, which is a simple form of spatial modulation. The bit error rate performance of line-of-sight (LOS) multiple-input and multiple-output (MIMO) was obtained in the literature with orthogonal subchannels for indoor millimeter-wave (mmWave) communications. It is essential to impose a rigid restriction on the distance between the transmitter and the receiver and antenna spacing to maintain orthogonal subchannels. However, in wireless communications, it is not viable to meet the strict distance requirements since user equipment is portable. We propose asymptotic orthogonal space shift keying with mobile stations. The asymptotic orthogonal space shift keying approaches orthogonal subchannels …

Model Mis-Specification Of Generalized Gamma Distribution For Accelerated Lifetime Censored Data, Marzieh Khakifirooz, Sheng-Tsaing Tseng, Mahdi Fathi

BCoE Publications

The performance of reliability inference strongly depends on the modeling of the product’s lifetime distribution. Many products have complex lifetime distributions whose optimal settings are not easily found. Practitioners prefer to utilize simpler lifetime distribution to facilitate the data modeling process while knowing the true distribution. Therefore, the effects of model mis-specification on the product’s lifetime prediction is an interesting research area. This paper presents some results on the behavior of the relative bias (RB) and relative variability (RV) of p-th quantile of the accelerated lifetime (ALT) experiment when the generalized Gamma (GG3) distribution is incorrectly specified as Lognormal or …

Prognostics Models For Railroad Tapered Roller Bearings With Spall Defects On Inner Or Outer Rings, Constantine Tarawneh, Jennifer Lima, Nancy De Los Santos, Robert Jones

Mechanical Engineering Faculty Publications

Rolling contact fatigue (RCF) is one of the major causes of failure in railroad bearings used in freight service. Subsurface inclusions resulting from impurities in the steel used to fabricate the bearings initiate subsurface fatigue cracks, which propagate upwards and cause spalling of the rolling surfaces. These spalls start small and propagate as continued operation induces additional crack formation and spalling. Studies have shown that the bearing temperature is not a good indicator of spall initiation. In many instances, the temperature of the bearing increases markedly only when the spall has spread across major portions of the raceway. In contrast, …

Nanoporous Gold And Other Related Materials, Keith Stine

Chemistry & Biochemistry Faculty Works

No abstract provided.

Pixelated Gasb Membranes For Photovoltaics: Fabrication And Structure-Property Relationships, Vijay Saradhi Mangu

Electrical and Computer Engineering ETDs

In this thesis, I present a reliable and efficient approach to heterogeneous integration of single-crystalline GaSb semiconductors with highly mismatched materials. The mismatch may refer to the crystalline structure and the thermal expansion coefficient of single-crystalline GaSb and the other materials of interest. The strategy of hetero-integration relies on epitaxial lift-off. This approach prevents the formation of extended structural defects that are detrimental to the performance of optoelectronic devices and preserves GaSb growth substrates for potential reuse.

Within my research work, I have overcome some outstanding challenges of epitaxial lift-off of GaSb, and I have demonstrated the operation of single-crystalline …

Effects Of Epoxy Adhesive Layer Thickness On Bond Strength Of Joints In Concrete Structures, Jaeheum Yeon, Yooseob Song, Kwan Kyu Kim, Julian Kang

Civil Engineering Faculty Publications

In the construction field, adhesives are frequently used to improve adhesion between two objects. Epoxy adhesives are applied as long-term solutions, improving the bond between repair materials and existing concrete structures. Experimental investigations of the relationship between the thickness of an adhesive layer and its shear strength have been conducted by a number of industries outside of the construction sector. However, that research used metal plates as adherends when determining the shear strengths of epoxy adhesives. Therefore, this study examines epoxy adhesives’ shear strength development when applied to concrete adherends. The test results show that the thickness of the bond …

Effect Of Project Lead The Way Participation On Retention In Engineering Degree Programs, Juliana Utley, Toni Ivey, John Weaver, Mary Jo Self

Journal of Pre-College Engineering Education Research (J-PEER)

A key goal of pre-college engineering programs is to increase the number and retention of students pursuing engineering degrees. The researchers conducted a transcript analysis in order to compare the retention of entering engineering majors at a university based on whether or not they participated in Project Lead the Way (PLTW) in high school. PLTW Engineering is a high school pre-engineering curriculum that offers a series of courses to increase student awareness and scaffold an understanding of engineering design. The findings from this study offer little support regarding the impact of students’ PLTW participation on engineering degree completion. However, findings …

Daylight Illuminance In Classrooms Adjacent To Covered And Uncovered Courtyards Under The Clear Sky Of Najran City, Saudi Arabia, Abdultawab M. Qahtan

Emirates Journal for Engineering Research

Daylight penetrating the classrooms makes students efficient, improves overall health and increases energy efficiency. In the hot regions, the concept of courtyards in buildings is deeply linked to the architecture as a sustainable solution to daylight indoors without negatively affecting the building cooling loads in the summer. Najran University has existing courtyards in college buildings. Recently, the university covered the courtyards using PVC canvas. This study aims to investigate and compare the daylight illuminance in classrooms adjacent to covered and uncovered courtyards. A case study of four classrooms in the College of Engineering was investigated under the clear sky of …

Dimensional Analysis Of Robot Software Without Developer Annotations, John-Paul W. Ore

School of Computing: Dissertations, Theses, and Student Research

Robot software risks the hazard of dimensional inconsistencies. These inconsistencies occur when a program incorrectly manipulates values representing real-world quantities. Incorrect manipulation has real-world consequences that range in severity from benign to catastrophic. Previous approaches detect dimensional inconsistencies in programs but require extra developer effort and technical complications. The extra effort involves developers creating type annotations for every variable representing a real-world quantity that has physical units, and the technical complications include toolchain burdens like specialized compilers or type libraries.

To overcome the limitations of previous approaches, this thesis presents novel methods to detect dimensional inconsistencies without developer annotations. We …

Emotion Recognition Using Facial Feature Extraction, Demiyan Smirnov

Theses and Dissertations

Computerized emotion recognition systems can be powerful tools to help solve problems in a wide range of fields including education, healthcare, and marketing. Existing systems use digital images or live video to track facial expressions on a person's face and deduce that person's emotional state. The research presented in this thesis explores combinations of several facial feature extraction techniques with different classifier algorithms. Namely, the feature extraction techniques used in this research were Discrete Cosine/Sine Transforms, Fast Walsh-Hadamard Transform, Principle Component Analysis, and a novel method called XPoint. Features were extracted from both global (using the entire facial image) and …

Quality Evaluation Of The Dewatering Subsurface Water In Urban Areas For Irrigation Purposes, Kuwait, Fawzia Al-Ruwaih, Mohamed El Anbaawy, Ahmad Abdelhalim, Abdulaziz Al-Shammari

Emirates Journal for Engineering Research

The objective of this study is to assess the quality of the dewatered groundwater and identify its suitability for irrigation purposes in an urban study area by analyzing its chemical composition. The water quality for irrigation has been assessed by the determination of the residual sodium bicarbonate (RSBC), potential salinity (P.S), sodium adsorption ration, (SAR), Mg ratio (MgR), sodium percentage (%Na⁺), Kelly’s ratio (KR), permeability index (P.I), electrical conductivity, EC, total dissolved solids TDS, total hardness (TH), and pH. The WATEQ4F computer program has been used to compute the saturation indices of some minerals with respect to water …

Reducing Threading Dislocation In Gasb Epilayer Grown On Gaas Substrate For Photovoltaic And Thermophotovoltaic Application, Ahmad Mansoori

Optical Science and Engineering ETDs

GaSb based photovoltaic devices have been demonstrated on GaAs substrates by an inducing interfacial array of 90° misfit dislocations. Despite the beneficial qualities of the highly stable 90° misfit dislocation, there is a significant density of residual threading dislocations in the GaSb layer, resulting in the degradation of the electrical performance of such photovoltaic cells compared to lattice matched devices. We aim to reduce threading dislocation density by optimizing growth temperature and by using an AlSb dislocation filtering layer. The growth temperature optimization results in a reduction of the threading dislocation density to 1.3 × 10⁸ cm⁻². …

Absorptive/Transmissive Frequency Selective Surface With Wide Absorption Band, Qingxin Guo, Jianxun Su, Zengrui Li, Lamar Y. Yang, Jiming Song

Department of Electrical and Computer Engineering: Faculty Publications

An absorptive/transmissive frequency selective surface (ATFSS) with absorption bands at both sides of a passband is presented. Equivalent circuits of the ATFSS that consists of a lossy frequency selective surface (FSS) and a lossless FSS were modeled. To improve the rejection at an undesired band, a transmission zero was introduced and controlled by loading the lossless FSS with four-legged loaded slots. The parasitic passband was suppressed when the cross structure in the lossless FSS was loaded with resistance. In order to expand the absorption band, loaded dipoles were utilized for the lossy FSS design. An ATFSS with wide absorption bands …

Advanced Photogrammetric Modeling Of Dranoc Kullas Using Small Unmanned Aircraft Systems, George Gebert, Liam Griffin, Justin Lawlor, Lauren Davis, Kylee Vander Velde, Sami Ali

Student Works

Small unmanned aircraft systems (sUAS), also known as drones, offer new capabilities for cultural heritage preservation activities. Student researchers from Embry-Riddle Aeronautical University have applied photogrammetric techniques based upon sUAS captured imagery to assist with historical site documentation and cultural heritage preservation in the Republic of Kosovo. Imagery from three locations -- Isniq, Dranoc and Junik -- highlight this work. Student researchers created georectified orthomosaics and 3D virtual objects. At each of these three locations the object of interest was a type of building known as a kulla. These kullas are fortified homes built for protecting large families and are …

Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 2. Comparison Of Theory And Dns, Sarma L. Rani, Rohit Dhariwal, Donald L. Koch

PRC-Affiliated Research

Part 1 (Rani et al. J. Fluid Mech. , vol. 871, 2019, pp. 450–476) of this study presented a stochastic theory for the clustering of monodisperse, rapidly settling, low-Stokes-number particle pairs in homogeneous isotropic turbulence. The theory involved the development of closure approximations for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions $\boldsymbol{r}$ . In this part 2 paper, the theory is quantitatively analysed by comparing its predictions of particle clustering with data from direct numerical simulations (DNS) of isotropic turbulence containing particles settling under gravity. The simulations were performed at …

Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 1. Drift And Diffusion Flux Closures, Sarma L. Rani, Vijay K. Gupta, Donald L. Koch

PRC-Affiliated Research

In this two-part study, we present the development and analysis of a stochastic theory for characterizing the relative positions of monodisperse, low-inertia particle pairs that are settling rapidly in homogeneous isotropic turbulence. In the limits of small Stokes number and Froude number such that , closures are developed for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions. The theory focuses on the relative motion of particle pairs in the dissipation regime of turbulence, i.e. for pair separations smaller than the Kolmogorov length scale. In this regime, the theory approximates the fluid …

Methods Of Use And Manufacture Of Silver-Doped, Nano-Porous Hydroxyapatite, Cheol-Woon Kim, Richard K. Brow

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

A silver-doped, nano-porous hydroxyapatite material is provided that can be utilized to capture radioactive iodine, ¹²⁹I. Methods of using the silver-doped, nano-porous hydroxyapatite material to remove radioactive iodine, and methods of manufacturing the material are also provided.

Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 1. Drift And Diffusion Flux Closures, Sarma L. Rani, Vijay K. Gupta, Donald L. Koch

PRC-Affiliated Research

In this two-part study, we present the development and analysis of a stochastic theory for characterizing the relative positions of monodisperse, low-inertia particle pairs that are settling rapidly in homogeneous isotropic turbulence. In the limits of small Stokes number and Froude number such that , closures are developed for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions. The theory focuses on the relative motion of particle pairs in the dissipation regime of turbulence, i.e. for pair separations smaller than the Kolmogorov length scale. In this regime, the theory approximates the fluid …

Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 2. Comparison Of Theory And Dns, Sarma L. Rani, Rohit Dhariwal, Donald L. Koch

PRC-Affiliated Research

Part 1 (Rani et al. J. Fluid Mech. , vol. 871, 2019, pp. 450–476) of this study presented a stochastic theory for the clustering of monodisperse, rapidly settling, low-Stokes-number particle pairs in homogeneous isotropic turbulence. The theory involved the development of closure approximations for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions $\boldsymbol{r}$ . In this part 2 paper, the theory is quantitatively analysed by comparing its predictions of particle clustering with data from direct numerical simulations (DNS) of isotropic turbulence containing particles settling under gravity. The simulations were performed at …