Engineering Section Research Articles

An introduction to additive manufacturing for undergraduate engineering students using authentic learning pedagogy and a project-oriented teaching-learning design

An application of authentic learning pedagogy through a project-oriented teaching-learning method was developed to introduce second year engineering students at Dalhousie University to additive manufacturing. Different projects are offered in five different discipline sections for students in the engineering design course. This paper focuses on a project offered to the Chemical Engineering section. The project introduces manufacturing skills by teaching additive manufacturing principles in the classroom, then incorporating a real-world design project by having the students design and build a 3D printhead for the laboratory 3D printer. Students applied design principles in this multidisciplinary project, collaborated in a team, and compared the performance of their printheads. This project was effective in teaching students design and manufacturing principles and increased their familiarity with 3D printing. The outcome of this project is shared in this paper so that it may be used by other instructors considering a similar project.

Data-driven classification of flow modes in unsteady galloping and its applications in flow mechanisms

Galloping is a divergent behavior of bluff bodies under aerodynamic forces and should be strictly suppressed in civil engineering. Considering that most studies focus on unsteady vibration response and lift, neglecting the overall flow field structure and its fundamental modes, this study explores the applicability of dynamic mode decomposition in modes classification according to sources of excitation, explaining the flow mechanisms associated with galloping. First, the results of an ideal section demonstrate the presence of two distinct modes in the uniform flow involving fluid-solid coupling issues, instability-induced mode (IIM) and movement-induced mode, respectively. Second, galloping stability is primarily determined by the phase of the first movement-induced mode, which is also verified in the complex engineering sections. Third, the energy contribution of these modes is dependent on vibration amplitude. In the complex engineering section, galloping exhibits amplitude dependence near the critical state, whereas this behavior is absent in the ideal rectangular section. This difference is closely related to the complexity of the frequency components in the IIM. This study contributes to a deeper understanding of unsteady galloping dynamics, offering insights for both theoretical research and practical engineering applications.

The Relationship Between Work Position Risk and the Level of Musculoskeletal Disorders in Private Limited Company Personnel

Musculoskeletal disorders (MSDs) are abnormalities that affect the musculoskeletalsystem, triggered by various risk factors in the work environment. Commonly, MSDs occur due to non-ergonomic working conditions. It arises from chronic exposure to risk factors that can cause injury to the musculoskeletalsystem, this condition will impact on the social and economic aspects of employees. This research was conducted to determine the characteristics of employees, description of the region and the level of musculoskeletal complaints experienced, risk of work positions based on RULA assessment, and the relationship between risk of work positions and the level of musculoskeletal complaints with an analytic cross-sectional design. The study sample was 33 employees of the Engineering Section of private limited company personnel. The research instrument used was a questionnaire. The results show that the majority of the Engineering Department employees at private limited company personnel were 23 years old (36.4%) and had worked for two to three years (33.3%). As many as 48.5% of employees experienced moderate levels of musculoskeletal complaints. Of the 33 respondents, the majority of employees (63.6%) had a low-risk position, nine people (27.3%) had moderate risk, and three (9.1%) had high risk. There is a significant relationship between the risk of work position and the level of musculoskeletal complaints (P < 0.05). There is a significant relationship between the risk of working position and the level of musculoskeletal complaints in personnel of limited liability companies. Keywords: employee health, musculoskeletal disorders (MSDs), level of occupational risk

Fuel–Water Emulsions as an Alternative Fuel for Gas Turbines: A Project Summary

The paper presents conclusions from research conducted at the Warsaw University of Technology in 2019–2023 regarding the combustion of fuel–water emulsions in a miniature gas turbine. The presented conclusions were made taking the current state of knowledge available in the literature into account. Particular emphasis was placed on explaining the discrepancies in the results of the experimental studies available in the literature. The main aspects of the combustion of the fuel–water emulsions that were analyzed were their impact on the emissions of NOx and CO, as well as the impact of the surfactant included in the fuel mixture on the combustion process, emissions and the formation of deposits on the walls of the combustion chamber. The impact of the emulsion fuel on fuel consumption was also discussed. In order to explain the changes occurring in the combustion chamber as a result of adding water to the fuel, numerical methods and methods of fluid mechanics were used. Studies have shown a positive impact of the use of fuel–water emulsions on CO and Nox emissions and fuel consumption. It was also demonstrated that fuel additives used for emulsification can create deposits on the walls of the hot engine section.

Chemistry and crystal engineering.

Recent studies published in the Chemistry and crystal engineering section of IUCrJ emphasize developments both in methodology and techniques as well as the diverse range of classes of compounds being studied and of problems being tackled.

Reconnaissance report on geotechnical damage caused by Tropical Cyclone Jasper in December 2023

This paper is focussed on the Department of Transport and Main Roads (TMR) initial geotechnical response to damages caused by Tropical Cyclone Jasper (TC Jasper) to road infrastructure and batter slopes along the state-controlled road network in TMR’s Far North Queensland (FNQ) District of Queensland, Australia. TC Jasper delivered extreme rainfalls over six days between 13 and 18 December 2023 in FNQ District. The highest accumulated total being 2,096mm in the area of Port Douglas and Mossman north of Cairns. Within areas of the TC Jasper path, rare to extremely rare rainfall occurrences resulted in severe flooding and geotechnical damage and closure of key state-controlled roads in FNQ. The roads closed included all four range crossings providing access to the Northern Tablelands. Communities were isolated, and tourism and regional transport severely impacted. This paper provides a report on the geotechnical damage caused by TC Jasper to seven key state-controlled roads in TMR’s FNQ District, and outcomes from the event reconnaissance approach used by TMR’s Engineering and Technology Geotechnical Section in collaboration with TMR FNQ District office and RoadTek teams to re-open most of the closed roads and secure significantly damaged road sections within four days of the cyclone passing. Ongoing recovery efforts are progressively re-opening remaining roads.

Implementation of the 5S work culture (Seiri, Seiton, Seiso, Seiketsu, and Shitsuke) in the engineering department of PT X, Sidoarjo

Work culture is closely related to the norms, beliefs, values, and attitudes formed in a company. One of the important work cultures owned by the company is the 5S culture or housekeeping whose application needs to be done as a form of self-protection of workers to stay safe in carrying out work activities so as to increase company productivity. PT X is one of the companies in Sidoarjo engaged in animal feed. The purpose of this study is to analyze in depth the implementation of the 5S work culture (Seiri, Seiton, Seiso, Seiketsu, and Shitsuke) in the Engineering Section of PT X, Sidoarjo. This research is a qualitative study with a descriptive approach, namely by providing a description of the actual conditions related to the implementation of 5S in the company. Data collection techniques are carried out by means of observation, interviews, and documentation studies. Based on the results of the study, the 5S work culture at PT X Engineering Section is still not optimally implemented. This is evident from the condition of the workplace that has not been well maintained, many unused items are in the workplace, and there are storage cabinets that are not labeled with information. The lack of awareness of workers regarding 3S habituation and the lack of supervision from management are inhibiting factors in implementing 5S optimally.

Effect of 3D-Printed Honeycomb Core on Compressive Property of Hybrid Energy Absorbers: Experimental Testing and Optimization Analysis.

This paper presents an innovative method of constructing energy absorbers, whose primary function is to effectively transform kinetic energy into strain energy in events with high deformation rates. Hybrid specimens are proposed considering thin-walled windowed metallic tubes filled with 3D-printed hexagonal honeycombs made of PET-G and ABS thermoplastic. The patterned windows dimensions vary from 20 × 20, 20 × 30, 15 × 20 and 15 × 30 mm2. Although using polymers in engineering and thin-walled sections is not new, their combination has not been explored in this type of structure designed to withstand impacts. Specimens resist out-of-plane quasi-static axial loading, and test results are analyzed, demonstrating that polymer core gives the samples better performance parameters than unfilled samples regarding energy absorption (Ea), load rate (LR), and structural effectiveness (η). An optimization procedure using specialized software was applied to evaluate experimental results, which led to identifying the optimal window geometry (16.4 × 20 mm2, in case) and polymer to be used (ABS). The optimized sample was constructed and tested for axial compression to validate the optimization outcomes. The results reveal that the optimal sample performed similarly to the estimated parameters, making this geometry the best choice under the test conditions.

Development of Web-Based Teleoperation VOCAFE Service Robot

The design and implementation of a service robot that communicates effectively via the MQTT Protocol is presented in this research. This study focuses on creating a web-based application to control and monitor the movement of restaurant service robots in one of the university's cafes called VOCAFE. This research uses the MQTT communication protocol which allows smooth interaction between the robot and the operator. The design and construction of service robots, including their mechanical parts and communication systems, is described in the engineering section. The test results show the response time of the robot's navigation system, showing performance within a reasonable range. The conclusion highlights the importance of additional testing and research to improve the system. Overall, this research advances the creation of teleoperated restaurant service robots with reliable and effective communication using MQTT.

Exploring the structural, mechanical and thermodynamic properties of Ti‐V solid solutions

AbstractAlthough Ti‐V based high‐temperature alloys are used in aerospace engine, rocket engine and hot sections, the structure and mechanical properties of Ti‐V alloys remains controversy. To explore the correlation between structural and mechanical properties, we apply employed the DFT method to study the phases stability, mechanical and thermodynamic properties of Ti‐V solid solution. Two Ti‐V solid solutions: Ti(V)ss solid solution and V(Ti)ss solid solution are discussed. Two Ti‐V solid solutions are thermodynamic stability. In particular, the Ti‐V solid solution prefers to form V(Ti)ss solid solution, in while the V(Ti)ss solid solution remains cubic structure. Furthermore, the Ti(V)ss solid solution is a mechanical instability. However, the V(Ti)ss solid solution is a mechanical stability. Here, the bulk modulus, shear modulus and Young's modulus of V(Ti)ss solid solution are 136.9, 23.5 and 66.7 GPa. In particular, the bulk modulus of V(Ti)ss solid solution is higher than the bulk modulus of the pure Ti. In addition, the V(Ti)ss solid solution shows better ductility compared to the pure Ti and V. Naturally, the stability and mechanical properties of V(Ti) solid solution is related to the Ti‐V metallic bond because of the localized hybridization between the Ti(3d) and V(3d).

1. Model‐Based Acquisition (MBAcq): Uniting Government and Industry around a Common Standard

AbstractThe Digital Engineering Strategy released in June 2018 outlined the DoD's strategic goals which “promote the use of digital artifacts as a technical means of communication across a diverse set of stakeholders.” Ultimately, by involving a variety of perspectives in the design decisions, one can increase quality and speed without increasing risks. “In addition to build, test, field and sustainment of defense systems, emphasis was placed on the acquisition and procurement of systems and the importance of digital engineering. This was further reinforced in the Feb 2022 release of the Engineering of Defense Systems Guidebook which contains Digital Engineering sections in each chapter. The norm for Systems Engineering has become Model‐Based Systems Engineering (MBSE) in which models are used at all phases of development. To complete the digital thread from concept to disposal, models will be required for the acquisition phase. This paper will describe Model‐Based Acquisition (MBAcq), and how it can be used to increase clarity for compliance and understanding in Systems and Software Acquisition.” (Hause, Hart, 2022) MBAcq can supplant the use of document‐based specification but only if we come together as an industry to develop and agree upon some standardization. A word of caution, model‐based approaches will only be successful if they are grounded in sound systems engineering practices. The thought process to create the models are as equally important as the resulting models themselves. This paper will discuss the work being done by the OMG MBAcq User Group, which is a broad industry body with participation from INCOSE, Armed Services, OUSD, DoD CIO, NDIA, DAU, FFRDCs and many industry suppliers, such as Boeing, Northrup Grumman, and Lockheed Martin, working together to successfully create both the standardization and guidance to successfully deploy MBAcq to the larger community. Parts of this paper were first published by the authors in (Hause, Hart, 202)

Borehole investigation on steep sloping ground

The Department of Transport and Main Roads (TMR), Engineering and Technology's (E&T) Geotechnical Section, have completed a research-based field trial aimed at developing a repeatable methodology to carry out geotechnical boreholes on steeply sloping ground. This has been presented in the context of slope failures, whereby the utilisation of this practise will provide subsurface information, which is directly representative of the area of interest, rather than that which is outside the landslide extent (current general practise within Australia). It is expected that the information gained from adopting this practice will enable optimum design and remediation treatments for landslides within Australia, and subsequently contribute strongly to sustainable project outcomes.

The Correlation between Awareness, Motivation, and Perception with Safe Behavior at Ngadiredjo Sugar Factory

Introduction: Sugar Factory (PG) Ngadiredjo is one of the manufacturing industry sectors where there are various stages of the production to process sugarcane into white crystal sugar. One of the risks of accidents in each production process is due to worker behavior. This study aims to analyze the strength of the correlation between awareness, motivation, and perception with safe behavior in engineering and processing section workers at PG Ngadiredjo Kediri. Methods: This research was an observational study with a cross-sectional approach. The sample of this study was 80 workers who were determined using the total population technique. Data collection techniques used questionnaires and safe behavior observations. The data obtained were analyzed descriptively using cross-tabulation and the Spearman correlation statistical test to determine the strength of the correlation between independent and dependent variables. Results: The results showed that most workers aged ≥ 36 years (42.5%), had a good level of awareness, good motivation, and fair perceptions. In addition, the results showed a strong correlation between awareness and perception with safe behavior and a very strong correlation between motivation and safe behavior. Conclusion: Based on the research results, there is a strong correlation between awareness and perception with safe behavior and a very strong correlation between motivation and safe behavior. The level of awareness, motivation, and perceptions of a worker will directly influence the level of his safe behavior.

Frontiers in medical engineering section in medical engineering technologies specialty grand challenge

SPECIALTY GRAND CHALLENGE article Front. Med. Eng., 31 March 2023Sec. Medical Engineering Technologies Volume 1 - 2023 | https://doi.org/10.3389/fmede.2023.1101299

How high is the quality of the videos about children's elbow fractures on Youtube?

ObjectivePediatric elbow fractures are children's most common fractures. People use the internet to get information about their illnesses and also to search for treatment options. Videos uploaded to Youtube do not go through the review process. The aim of our study is to determine the quality of videos related to child elbow fractures on Youtube.Material methodThe study was carried out with the data obtained from the video-sharing site www.youtube.com on 01.12.2022. Pediatric elbow fractures are written in the search engine section. Information about the number of views of the videos, upload date, view rate (number of views per day), number of comments, number of likes and dislikes, duration, whether they contain animation and the publishing source were evaluated. The videos are divided into 5 groups according to their sources: medical society/non-profit organization, physician, healthrelated website, university/academic, and patient/independent user/other. The quality of the videos was evaluated using the Global Quality Scale (GQS). All videos have been evaluated by 2 researchers.ResultsIn the study, 50 videos were included. In the statistical evaluation, no significant correlation was found between the modified discern score and GQS found by both researchers, and the number of views, the rate of views, comments, likes and dislikes, video duration and VPI. In addition, when the GQS and modified discern scores were compared according to the source of the video, it was found that the patient/independent user/other group scores were lower numerically, but there was no statistically significant difference in comparison.ConclusionMost of the videos about child elbow fractures have been uploaded by healthcare professionals. Therefore, we concluded that the videos are quite informative in terms of accurate information and quality content.

АНАЛИЗ КИНЕМАТИЧЕСКОЙ СХЕМЫ ПОРШНЕВОГО W-ОБРАЗНОГО ДВИГАТЕЛЯ С ПРИЦЕПНЫМИ ШАТУНАМИ

This article presents the analysis and results of analytical, calculation, and design solutions for the development of piston engines for aircraft (tractors, automobiles, etc.). The authors propose an original design of a W-shaped engine with trailer connecting rods and made a comparative analysis of design features. The main feature of the W-shaped engine design is a significant reduction in length, and, consequently, the length of the crankshaft. As known, the manufacturing of internal combustion engine crankshafts is a long, complex, and expensive procedure requiring a number operations for its mechanical and heat treatment. An important aspect of crankshaft design is the calculation of mechanical tension, torsional vibrations, and the hydraulic performance evaluation of the main and connecting rod bearing, including engine balancing as a whole. At the end of the article the operating schemes of the engine section are presented (the section consists of four pistons, two main and two connecting rods bearing kinematically connected to one crankpin). The design differences from the classical schemes of crank-connecting mechanism (CCM) allow us to design the W-shaped engine in accordance with the technical requirements. For example, maximum power can be achieved by using variant “A”, with an increase in the power and heat stress of the parts of the cylinder-piston group (CPG), when the section is organized according to variants “B” or “C”, the loading of CCM parts is increased, but the loading of CPG parts is reduced. Considering that a W-shaped engine with trailed connecting rods has a same piston stroke in main and side cylinders and the workflow pattern in each cylinder is identical and is moved at the crankshaft rotation angle – which allows the engine to be designed according to variants above – the performance characteristics of such an engine are significantly expanded due to electronic control. The authors consider continuation of the work in the implementation of a full set of calculation studies taking into account the design features of the engine with a W-shaped design of CCM.

INTERFERENCE RESISTANCE OF A CORRELATION RECEIVER AT A LIMITED OBSERVATION INTERVAL

The article considers the possibility of increasing the capability of detecting a useful radio signal against the background of noise and simultaneously reducing the possibility of mistaking noise fluctuations for a signal. Moreover, if it is absent then the Neumann-Pearson statistical test should be used. This criterion is a partial case from the class of criteria consisting in the calculation of the likelihood ratio and does not require knowledge of a priori probabilities of the presence or absence a useful signal while constructing an optimal receiver and Bayesian methods are used.
 The effectiveness of the detection procedure according to the Neumann-Pearson test is characterized by the probability of correct detection at a fixed false alarm probability. These probabilities depend on the signal-to-noise ratio at the output of the detection device. So, an important preparatory stage of the reception immunity analysis is the study of this parameter which is very important in the section of statistical radio engineering.
 It is known that the optimal detection of a signal against a background of white noise is reduced to the correlation integral calculation. This calculation can be done directly by using a multiplier and integrator (correlation method), by using a filter that is optimal for this signal (filter method) or by using a correlation-filter method.
 The presence of a priori uncertainty during signal reception makes it impossible to create an optimal (consistent) receiving path and therefore makes it impossible to obtain the required value of the signal-to-noise ratio at the output of the detection device. In this case, an autocorrelation algorithm is used which is resistant to a priori uncertainty of signal parameters and is “optimal” while detecting signals of unknown shape. The most general character for determining the signal/noise ratio has an expression for the case of an incoherent single-channel autocorrelation algorithm for detecting a noisy signal against a background of stationary white noise (interference).
 For example, quite a large number of scientific works are devoted to the interference immunity issue of the correlation reception method. They mainly consider the interference immunity of correlation receivers when a mixture of harmonic signal and noise passes through them. The circuits with the same average frequencies of multiplying processes and etc. are analyzed. There are also known works in which formulas relating the value of the signal-to-noise ratio at the output of the receiving path for a complex signal to the input signal-to-noise ratio are given.
 In the above works, idealized cases are considered, namely, when the observation is conducted on a fairly long observation interval but the real observation interval is quite limited. In this case, the averaging is carried out over a limited time interval and it is necessary to take into account the intercorrelation relations between the signal and noise, therefore, along with the signal-signal, noise-noise, signal-noise and noise-signal components, we will have the following mutual correlation moments between the combinations of signal and noise component.
 The issue of an autocorrelation receiver when passing an additive mixture of signal and white noise at a limited observation interval is investigated in which the immunity index is considered and a general solution of the signal/noise ratio based on the deviation criterion is obtained. Therefore, obtaining an analytical expression that establishes the relationship between the signal-to-noise ratio at the input and output of the receiver is very important and relevant.
 The purpose of the article is to obtain an analytical expression of the signal-to-noise ratio value at the threshold device input of an incoherent autocorrelation receiver at a limited observation interval.

Life Cycle Assessment for Rough Machining of Inconel 718 Comparing Ceramic to Cemented Carbide End Mills

Abstract Nickel-based alloys such as Inconel 718 belong to the group of heat-resistant super alloys. Combined with good mechanical properties over a wide range of temperatures, nickel alloys are used extensively in the aero engine sections exposed to elevated temperatures. Besides turbine blades and disks, integrally designed compressor rotors (Blisks) in the high-pressure compressor are increasingly made of Ni alloys. This is the result of an efficiency-driven increase in temperature levels in the rear compressor stages. The machining of these hard-to-machine materials is characterized by low productivity and high tool wear. Compared to the machining with conventional cemented carbide end mills, innovative SiAlON ceramics offer a significant potential to increase the performance of these machining processes while saving cooling-lubricants. Besides an increase in productivity, the evaluation of the overall environmental impact of specific manufacturing processes is gaining importance in the context of more sustainable product life cycles. This paper focuses on the comparison of different milling strategies in the production of high-pressure compressor rotors made from Inconel 718 in a cradle-to-gate assessment based on DIN EN ISO 14040/44. Thus, the ecological impact of both the state-of-the-art and the novel SiAlON roughing strategy are evaluated considering the consumption of energy, water and compressed air as well as the tool wear. The life cycle impact analysis (LCIA) will be performed as a midpoint analysis taking multiple indicators into account such as the global warming potential (GWP).

Myths and Realities of the Salt Lake Temple Foundation

Myths and Realities of the Salt Lake Temple Foundation

Exploration of Sub-grade and Pavement Construction in the Settlement Section of Municipal Road and Bridge Engineering

Exploration of Sub-grade and Pavement Construction in the Settlement Section of Municipal Road and Bridge Engineering