Basic Engineering Research Articles

Electrochemical sensors: basic principles, engineering, and state of the art

Electrochemical sensors: basic principles, engineering, and state of the art

Proposed Project Selection & Prioritization Framework during Front-End Planning (FEP) for Revitalization Project Portfolio at Indonesian Oil Refinery Plant

Abstract— Due to their aging, refinery facilities face the threat of suffering from incidents and accidents. Even fatal injury may be caused if running without proper maintenance planning. The revitalization project is performed intended to replace, repair, or increase production capacity at an existing refinery. Like other projects in the construction sector, the revitalization project tends to experience the same common flaws in their performance; project delay, cost overrun, scope creeping, operational mishaps, and canceled or stopped. The best time for a project to experience idea development, conduct scope changes, prepare excellent project engineering, etc., is at the Front-end Planning stage. This paper focused on project selection and prioritization at the Front-end Planning. The focus is then zoomed in to the sub-stage of Front-end Planning (initiation, conceptual, and basic engineering design). The aim is to eliminate the infeasible and unpromising projects that cannot meet the requirement. This focus is necessary before more resources are expended, which can ignite catastrophic events in the organization, primarily financial.The literature reviews have been done on the references to develop a comprehensive framework that decomposes the front-end planning into three sub-phases, providing the platform for project selection in each stage with its different focus and objectives. The new framework is proposed emphasizing the gate review and decision gates for those three sub-stages under the Front-end planning phase. The framework also provides the windows of having different selection criteria at each stage; hence the proper criteria will be efficiently used at the right time. Project proposals must go through a prioritization process since the organization's resource is not unlimited. Project proposals would experience the evaluation and selection as an individual project and, at a subsequent level, would be evaluated as part of the project proposals pool where the Project Management Office will prioritize the suitable projects worth execution.

A New design of deployable pedestrian bridge deck based on origami theory

As one of the basic civil engineering structures, bridges greatly impact people’s daily life. However, many bridge accidents are caused by boat crashes because of the driver’s carelessness or other climatic and hydrological factors. Besides, some pedestrian bridges are not frequently used and thus make a waste of water space. This design will overcome the challenge and tackle the problem successfully based on the origami and kirigami theory by using a connector composed of a slider and a revolute joint. The bridge can be folded up and down via a particular folding method. The basic structure units have two degrees of freedom (DOF). The whole mechanism can be folded and unfolded by sliding and rotating the connector. According to the structural folding position analysis results shown in the diagrams, the new deployable bridge deck structure design can validly tackle the problems of clearance limitation under the bridge via the special-designed cross-section of the bridge deck. I hope the design model will be widely applied in the river-crossing bridge and bring convenience to all pedestrians and boat drivers.

Application of the Cooperative Script Learning Model to Improve Student Learning Outcomes in Basic Competencies Understanding Various Styles in Building Structures at SMK Negeri 1 Lotu for the 2022/ 2023 Academic Year

The problem in this study is that the Cooperative Script learning model has not been optimally applied to the Basic Competence of Understanding Various Styles in Building Structures and student learning outcomes are limited to achieving KKM, namely 70. Research objectives: (1) To describe the learning process by applying the Cooperative Script learning model on Basic Competency of Understanding Various Styles in Building Structures at SMK Negeri 1 Lotu for Academic Year 2022/2023, and (2) To find out student learning outcomes for Basic Competency for Understanding Various Styles in Building Structures at SMK Negeri 1 Lotu for Academic Year 2022 /2023. This type of research is Classroom Action Research (CAR). This research was conducted at SMK Negeri 1 Lotu with research subjects of class X DPIB, totaling 22 people. The instruments in this study were observation sheets of the learning process (teacher respondents), observation sheets of student activity, photo documentation, and learning achievement tests. With the data analysis technique, namely the observation sheet is processed with a Likert scale and the learning achievement test is carried out by validation test and test feasibility test. Research results: (1) In cycle I (First) the average percentage of observations in the learning process (teacher respondents) is 65.63%, the average percentage of observations of student activity is 48.44%, the average learning outcomes count is 65.78 with a percentage of student completeness of 45.45% and this result has not reached the target that has been set, namely 70. (2) While in cycle II (two) the average percentage of observations in the learning process (teacher respondents) is 87.50%, the average percentage of observations of student activity is 81.25%, the average student learning outcomes is 81.36 which is categorized as good with a complete percentage of student learning outcomes of 100% and has reached the set target of 70. From the research findings above it can be concluded that by applying the Cooperative Script learning model to the Basic Competency Engineering Mechanics subject of Understanding Various Styles in Building Structures can improve student learning outcomes at SMK Negeri 1 Lotu.

Structural features underlying crunchy property of konjac glucomannan gels

Fundamental understanding of structure-property relationships of konjac glucomannan (KGM) gels has been increasingly important in design of food products. Compared to basic physical or engineering properties, the properties directly perceived by human subjects and related structural features are yet less explored. Here we address this issue based on experimental researches and theoretical calculations. Our findings agree with those for low-moisture foods that crunchiness-stiffness correlations exist and there appears to be a low limit of 0.16 kPa on the yield stress for KGM gels being highly crunchy. Notably, the crunchy property depends on a large dimension (up to 1 mm) of gel architecture. Gel networks formed by KGM are recognized to be responsible for the crunchy property of corresponding gels and inclusion of starch particles otherwise reduces the crunchiness. The particular length scale from 0.5 to 1 μm manifests itself dominant in conferring the crunchy mouthfeel to KGM gels.

Contribution of Agility and Flexibility to Football Dribbling Skills in Junior High School Extracurricular Students

Dribbling is a basic engineering skill most often used by football players in both amateur and professional classes. Because with dribbling therapy, it can help the effort to score goals into the opponent's goal as the ultimate goal of the football game. This study aims to find out the magnitude of the contribution between agility to dribbling ability in extracurricular football students, then find out the magnitude of the contribution between flexibility to dribbling ability in extracurricular football students of SMP N 2 Liwa, as well as to know the magnitude of the contribution between agility and flexibility to the dribbling ability of football extracurricular students. The sample of this study was 30 junior high school extracurricular students with male gender. The method used is descriptive correlational, which is a study that aims to describe or describe events or events that are taking place at the time the research is carried out without regard to before and after with a validity value of 0.67, and test reliability of 0.79. The results of this study are Agility contributes to dribbling skill results by 50.12%, while the rest is influenced by other variables, flexibility contributes to dribbling skill results by 28.19%, while the rest is influenced by other variables, agility and flexibility contribute to dribbling skill results by 55.65%. Keywords: agility, flexibility, dribbling skills, students.

Advances and Future Prospects of Wearable Textile‐ and Fiber‐Based Solar Cells

Carbon neutrality is one of the most urgent global missions and has promoted the development of clean and renewable energy sources. Sustainable photovoltaic cells have become ideal candidates for green energy harvesting owing to their high power conversion efficiencies and low production costs, which can efficiently reduce the carbon emissions. In recent years, with the increasing advancements in wearable electronics, flexible photovoltaic textile devices have been regarded as the most promising energy resources for Internet of Things. Accordingly, herein, an up‐to‐date account of the recent advancements in modern textile‐based solar cells (i.e., organic, perovskite, and dye‐sensitized solar cells) based on both fibers and fabrics for highly effective harvesting of solar energy is provided, and their fundamental designs and optimization strategies are comprehensively reviewed. This review emphasizes the unique characteristics, underlying mechanisms and potential applications of textile‐based solar cells. Moreover, a modern perspective on both challenges and opportunities in the advancements of the interesting textile‐based solar cells embedded in wearable devices is elucidated. This review offers new insights into advanced energy technologies and smart wearable devices that would facilitate multidisciplinary integration of basic science, device engineering, industrial applications, and other scientific domains.

Study on some Properties of Sustainable Mortar Incorporating Processed Waste Tea Ash

The use of industrial waste materials as a substitute for cement in the manufacture of mortar is an alternative approach to reduce carbon dioxide emissions in building construction. In this study, processed waste tea ash (PWTA) obtained from the extraction tea plant was used to partially replace 0-40% cement in the manufacture of mortar. The effects of PWTA on the basic engineering properties of mortar are evaluated and compared to mortar without PWTA. Test results showed that workability and density of mortar decreased with increases in the PWTA content. Furthermore, no decline in compressive strength of concrete was observed up to 20% replacement of cement with PWTA at 7, 28 and 90 days and beyond that, the compressive strength decreased. Results obtained from this study indicate that PWTA can be used as partial replacement of cement up to 20% with comparable strength with normal mortar. This approach helps to minimize the usage of cement in mortar production and can reduce the negative impact of PWTA on the environment.

Application of People Tutor Methods to Increase Learning Achievement of Mechanical Measuring Equipment to Basic Automotive Engineering

Application of People Tutor Methods to Increase Learning Achievement of Mechanical Measuring Equipment to Basic Automotive Engineering

MODULE’S INFLUENCE ON BASIC ENGINEERING MECHANICS’S LEARNING OUTCOMES OF CIVIL ENGINEERING STUDENTS

Modules are teaching materials that contain learning objectives, learning material/substance and evaluation so that students can learn independently and be more active in learning. The purpose of this study was to determine the effect of using the module on student learning outcomes in first semester of the Civil Engineering Study Program, Faculty of Engineering, Graha Nusantara University in the Basic Engineering Mechanics course and the magnitude of the increase in learning outcomes. The research method used was quasi-experimental method with a pretest-posttest control group design. The number of samples is 40 students, which are divided into two groups. Data collection uses test techniques (questions) through pre-test and post-test. Data processing was performed using Statistical Product and Service Solution (SPSS) version 21.0 for Windows. Based on the results of the t-test, it was found that tcount ≥ ttable or 4.2058 ≥ 2.023 meaning that Ho is rejected or Ha is accepted. So that the module-based learning model affects the learning outcomes of Basic Engineering Mechanics students of the Civil Engineering Study Program, Graha Nusantara University Padangsidimpuan with an increase in learning outcomes of 41.86%. Meanwhile, the conventional learning model is only able to increase the learning outcomes of Basic Engineering Mechanics by 28.69%. The module-based learning model has a percent effectiveness of 35.19% to improve Basic Engineering Mechanics learning outcomes. Thus, the application of a module-based learning model is very suitable and effective for colleges used.

Training on the Basic Communication Development and Basic Teaching Skills at the 3rd Batch of Basic Instructional Technique Skills Improvement Training (PEKERTI) at the University of Bengkulu

This training aims to train lecturers in developing the basics of Communication and Basic Teaching Skills in PEKERTI (Basic Instructional Engineering Skills Improvement) Batch 3 2023 activities. The activity was carried out in May 2023 at the University of Bengkulu, with 53 participants in the training who were lecturers from the Singaperbangsa Karawang University College. The research instrument used was a closed questionnaire with four answer choices. The data analysis technique used is descriptive statistical analysis. PEKERTI participant response analysis related to training activities was carried out on the data obtained as a percentage. Percentages are obtained based on modified Likert Scale calculations. The research results show that almost 80% of the respondents were in the Strongly Agree category based on the guidelines in Table 4 of the Likert scale interpretation. Moreover, only one respondent is in disagree category. In other words, the respondents who were the sample in this study only gave answers that strongly agreed and agreed to the 52 positive statements submitted in the questionnaire developed regarding training on Basic Communication Development and Basic Teaching Skills at the 3rd Batch of Basic Instructional Technique Skills Improvement Training (PEKERTI) at the University of Bengkulu. In conclusion, the training for developing the Basics of Communication and Basic Teaching Skills in PEKERTI Batch 3 at the University of Bengkulu received a positive response from the participants.

Engineering and navigating calculation the flight of unmanned aircrafts of tactical class

The regulatory documents of the Ministry of Defense of Ukraine provide for navigational training of the crews of unmanned aircraft complexes and establish the necessity of having a navigational plan and an engineering-navigator flight calculation at the workplace of an external UAV pilot. The article notes that today there are no normative documents that would establish the content and scope of engineering and navigational calculations and methods of their implementation for unmanned aircraft complexes of tactical classes. The article as a whole is devoted to the consideration of issues of methodical support of navigator training of crews of unmanned aerial systems of the tactical class with an electric power plant. It is indicated that, based on the tactical and technical capabilities of UAVs of tactical classes, the nature of the tasks performed by them and the typical educational level of their external pilots, the creation of the most simplified methodology for performing basic engineering and navigational calculations of UAV flights is required. The mathematical complexity of such a method should not go beyond general secondary education. When performing navigational calculations of aircraft flights, the main difficulty is created by the problem of taking into account the influence of the wind. Simple algorithms for calculating the correction to the wind drift course, road speed and flight duration on straight sections of the route and sections of U-turns in the presence of wind are proposed. Algorithms for calculating the total need for energy resources for a flight along a given route and for separate sections of the route, including additional energy resource needs for sections of altitude gain, are proposed. Recommendations for evaluating the energy capacity of the battery available for flight performance are given. An algorithm for calculating the critical reserve of energy resources, which is necessary for the possibility of returning the UAV from the farthest point of the route under meteorological conditions for the scheduled flight time, is proposed. Options for full and abbreviated engineering and navigational calculations are offered.

The odyssey to next-generation computers: cognitive computers (κC) inspired by the brain and powered by intelligent mathematics

Cognitive computers (κC) are intelligent processors advanced from data and information processing to autonomous knowledge learning and intelligence generation. This work presents a retrospective and prospective review of the odyssey toward κC empowered by transdisciplinary basic research and engineering advances. A wide range of fundamental theories and innovative technologies for κC is explored, and a set of underpinning intelligent mathematics (IM) is created. The architectures of κC for cognitive computing and Autonomous Intelligence Generation (AIG) are designed as a brain-inspired cognitive engine. Applications of κC in autonomous AI (AAI) are demonstrated by pilot projects. This work reveals that AIG will no longer be a privilege restricted only to humans via the odyssey to κC toward training-free and self-inferencing computers.

Engineering properties of fine-grained red mud

ABSTRACT Basic engineering parameters of fine-grained red mud tailings were evaluated via laboratory tests; the coupled effect of mineralogy and microstructure was investigated by appraising the stress-deformation characteristics; and the static and seismic liquefaction susceptibilities were evaluated via critical state soil mechanics and empirical equations, respectively. Results indicated the presence of cementitious minerals without swollen clay minerals. The textural and compression properties were similar to those of clays, whereas the strength parameters were similar to those of sand. The stress-deformation curves show overall strain softening with a temporary strain-hardening curve at the beginning, which can be qualitatively explained by the coupled effect of the microstructure and mineral components. Hydroxysodalite precipitated at the contact points among the particles afforded microstructural cementation bonds, allowing the aggregates to resist external loads at the initial loading stage. Red mud presented strong resistance to static liquefaction but was potentially seismically liquefiable.

Lab-Tec@Home: Technological Innovation in Control Engineering Education with Impact on Complex Thinking Competency

The objective of this paper is to present the results of the implementation process of the Lab-Tec@Home kit, an educational innovation that allows students to set up home laboratories to test and validate basic control engineering concepts. Specifically, the purpose of this study is to measure the acquisition and development of students’ perceived achievement of complex thinking competency during this educational practice, considering how valuable it is to improve their perception of additional skills while fulfilling the objectives of the innovation. We implemented a validated instrument to measure this competency before and after using the Lab-Tec@Home kit and in a control group where this educational innovation practice was not carried out. Although the results did not show a statistically significant difference in the level of perception or the improvement achieved between the groups, they indicated an impact on the homogeneity of the students’ perceived skills, which is a value of this educational tool and its greatest finding and contribution.

Structural, morphological, rheological study of chitosan modified bitumen composite

The unavoidable aging of road pavements due to years of exposure to heavy traffic volume and climatic and environmental changes finally results in a decrease in the performance of the asphalt binder and the performance of the pavement. One of the major causes of road failures is due to poor performance of bitumen pavements and their maintenance. Rutting during hot summer and cracking during winter are the most common problems in the performance of bituminous roads (50 mm or thicker). In the present study, chitosan which is a crustacean waste, and nitrile butadiene rubber (NBR) which is a shoe sole waste are used as reinforcement materials in bitumen. Basic engineering tests rolling thin film test (RTFO), pressure aging vessel (PAV), etc, were performed on the bitumen composite to understand the impact of additives on bitumen’s physical characteristics. Advanced characterization methods, including x-ray Diffractometer (XRD), Scanning electron microscopy (SEM-EDAX), Raman Spectroscopy, Dynamic Shear Rheometer (DSR), Multiple stress Creep recovery (MSCR) were employed to examine the structural, morphological, compositional, and performance characteristics of bitumen.

Penerapan Aplikasi Simulasi Liveware 2.3 pada Mata Kuliah Dasar Teknik Tenaga Listrik

This study aims to determine the effect of using the Liveware 2.3 simulation application on student learning outcomes in the Basic Electrical Engineering Course in the Department of Electrical Engineering Education, Manado State University. This research is a pre-experimental study with a one-group pretest-posttest design. The population of this study were students in semester 1 class of 2022 majoring in Electrical Engineering Education. The sample taken consisted of one class, namely Class A1 2022, which consisted of 18 people. The data analysis technique used to analyze the research data is by testing through statistical calculations. Student learning outcomes after being given treatment show better results, this can be seen in the average pre-test score of 51.23 and post-test of 72.50. The increase difference is 21.27. The results of the t-test show an increase in learning outcomes with a Tcount of 2.23 which is consulted on Ttable 1.64. Thus, student learning outcomes after being treated with the Liveware 2.3 simulation application show good results. Student learning outcomes after being given treatment (post-test) are better than before being given treatment (pre-test). With an average learning result of 72.50 and obtained Tcount = 2.23>Ttable = 1.64.

Analysis on Effectiveness of Testing and Evaluation of Bridge Repair and Reinforcement

Bridge engineering is an important part of basic engineering in today’s transportation field, and its quality and performance have a vital impact on the improvement and development of modern transportation engineering. With the continuous development of transportation engineering, the maintenance and reinforcement of existing bridges are also being given more emphasis. In order to scientifically evaluate the effectiveness of bridge maintenance and reinforcement, this paper analyzes its detection and evaluation, including the significance, key points, and main methods of detection and evaluation. Therefore, this analysis aim to provide some reference for the maintenance and reinforcement and the quality improvement of bridge engineering.

Mobile Application Design For Learning Digital Engineering Based On Figma And Android Studio

The purpose of this research is to create and implement effective learning media to facilitate lecturers and students in conducting learning at the Electrical Engineering Study Program, Faculty of Engineering, University of Muhammadiyah Sumatera Barat, namely designing Teknik Digital App learning applications by designing using use case diagrams, making the system in accordance with the design that has been made and implement the system that has been created and perform testing on the system. In collecting data, researchers used the method of observation, interviews and literature study. Meanwhile, in developing the system, researchers use the type of Research and Development (R&D) research referring to the waterfall model. Applications made using Android Studio, Figma and Adobe Illustrator CS3. The application that has been made is tested using the black box testing method. This research produces a Teknik Digital App learning application that helps parties in carrying out the learning process during lectures and also helps students to make it easier to learn basic digital engineering materials anywhere and anytime.

An experimental and numerical study on the wear mechanism of cutters on workover bits under thermo-mechanical coupling

The workover bit is the core tool for removing mental junk in the wellbore and determining construction efficiency. In order to solve technical bottlenecks of slow footage and fast wear, a thermo-mechanical coupling analytical model of cutter on workover bit was proposed based on the principle of the heat source method, which clarified the quantitative relationship between temperature, structure, and physical parameters. Also, a thermo-mechanical coupling 3D numerical model of cutter was proposed by the penetration contact algorithm of temperature-displacement coupling, which revealed the chip formation mechanism and distribution characteristics of high-temperature areas. Besides, as the severe conditions of insufficient cooling of workover bits, the non-cooling milling experiment of the workover bit with single cutter was carried out. Then the wear morphology characteristics and wear mechanism under the action of thermo-mechanical coupling were explored. The results show that the temperature error of the thermo-mechanical coupling numerical model of cutter is within 13.0%, which meets the accuracy requirements of basic engineering analysis. Under the action of thermo-mechanical coupling, the workover bit produces roll-shaped chips with a curvature radius of 2.03 mm. The high-temperature area of cutter is distributed on the outside of the cutting edge. In the meanwhile, the temperature on the rake face of cutters has the fastest increase and the highest temperature, and the highest temperature can reach 541.6 °C. The wear mechanism of cutter can be divided into four stages: gradual indentation stage, mechanical wear stage, bond wear stage, and high-temperature oxidation stage. When milling continuously for 5 min, the wear volume of the cutter reaches 0.51 mm3, and controlling temperature is the key to reducing the wear of the cutter. This research can provide theoretical guidance and a scientific basis for revealing the wear mechanism and prolonging the service life of workover bits.