Common Engineering Problems Research Articles

An improved multi-strategy Golden Jackal algorithm for real world engineering problems

The Golden Jackal Optimization (GJO) algorithm is a novel, nature-inspired optimization technique that has gained recognition as a highly promising metaheuristic due to its notable efficiency and adaptability. However, the GJO algorithm possesses several shortcomings, including inadequate exploitation ability, vulnerability to local optima, and imbalanced exploration-exploitation. Therefore, this paper presents an enhanced version of the named mGJO, tailored explicitly for addressing real-world engineering and feature selection problems. The mGJO incorporates four improvements to the standard GJO. To begin with, Chaos-OBL (COBL) based population initialization is proposed to increase diversity in population. Secondly, a nonlinear control parameter is proposed to regulate the exploration-exploitation transition. Thirdly, the original updating rule of GJO is combined with the ESQ mechanism to prevent the leader solutions from influencing the local optimal solutions. Finally, a new adaptive mutation strategy is presented to alter individuals and improve positions based on their fitness. To evaluate the efficiency of the suggested mGJO is assessed using CEC2005, CEC2017, CEC2020 and CEC2022 benchmark functions. The proposed mGJO is also applied to five common real-world engineering problems and is also applied to the feature selection problems to assess its performance. Furthermore, the proposed mGJO is compared with various advanced algorithms to evaluate its performance. Statistical analyses, including the Friedman rank test and Wilcoxon test, are applied to the experimental data to validate the superiority of the extracted results. The experimental results and the statistical analysis indicate the superiority of mGJO in terms of convergence rate, solution quality, and optimization accuracy.

Study on the Methods of Strengthening Reinforced Concrete Beams with CFRP

After the long-term use of reinforced concrete structures, there may be structural aging and structural damage, these common engineering problems. As a result, the performance is reduced, so it is necessary to strengthen to meet the corresponding safety requirements. Carbon Fiber Reinforced Polymer (CFRP) has the advantages of lightweight, strong, high tensile strength and tensile degree. Therefore, CFRP is widely used in reinforcement. Based on CFRP reinforcement of reinforced concrete beams, this paper analyzes its reinforcement methods. The paper mainly analyzes the influence of different pasting methods of CFRP on the performance of beams and the influence of material pasting thickness on beams. Through the analysis and research, it can be concluded that CFRP has certain advantages compared with traditional reinforcement materials. Therefore, it can be used to reinforce reinforced concrete beams. This study can provide some reference value for some related projects of reinforced concrete beams reinforced by CFRP.

Research on flow field characteristics in the karst tunnel face drilling hole (conduit) under the coupling between turbulence and seepage

Tunnel water inrush is one of the most common engineering problems during tunnel construction and operation, especially in karst aquifers. Among them, tunnel face drilling holes and karst conduits are strong water conductivity channels (called the “conduit” here), while the porous rock matrix is a weak water conductivity area. A second-order accuracy tunnel face water inrush model is established to investigate the coupling between the turbulent flow in the conduit and the seepage in the porous rock matrix. In the model, the incompressible Reynolds average Navier–Stokes (RANS) equation and the Brinkman-extended Darcy equation are used to govern the turbulence in the conduit and seepage in the porous rock matrix, respectively. The expressions of velocity distribution and water inflow discharge are derived requiring the velocities and their gradients of the turbulent and seepage flow to be equaled at the flow-solid interface. The validity of the present model is verified by the existing analytical solutions and COMSOL numerical solutions. Furthermore, parameter sensitivity results show that the velocity has a positive relation with the Laplace parameter, Reynolds number, Darcy number, and conduit radius. Finally, the tunnel face water inrush in the new Zhongliangshan expansion tunnel is selected as a real field engineering case. The error of the water inflow discharge in the tunnel face drilling hole between the present predicted results and the field measured results is within 10%. After introducing cosine fluctuation with amplitude 0.15 and period 500 s to optimize the model, the error for the stable water gushing stage can be reduced to within 5%. This model can provide a reference for predicting the water inflow discharge in the drilling holes or karst conduits on tunnel faces.

Plugging performance and mechanism of an oil-absorbing gel for lost circulation control while drilling in fractured formations

Lost circulation of drilling fluid is one of the most common engineering problems in the drilling process of fractured formations. In this study, an oil-absorbing polymer gel synthesized using compound monomers with rigid and flexible chains was applied to control the oil-based drilling fluid loss while drilling. The microstructure, oil-absorbing performance, and plugging performance the gel was investigated. A large number of dense pores on the surface of the gel were observed, which allowed the oil molecules to enter the internal space of the gel. The initial oil absorption capacity of the gel was fast, and it increased with the increase in the temperature and decrease in the particle size, reaching 20.93 g/g at 140 °C. At a high temperature of 140 °C, the bearing pressure capacity of the gel formula containing particles of different particle sizes reached 7.6 MPa for a fracture of a width of 3 mm, showing that the oil-absorbing gel have excellent plugging performance at high temperature. Plugging mechanism of the gel was investigated through visualized fracture plugging experiments. Results show that the dynamic migration, particle-swelling, particle-bridging, particle-aggregation, deformation-filling, and compaction-plugging contribute to the whole lost circulation control process, reflecting that the plugging performance can be effectively enhanced by improving the aggregation and filling degrees of the gel with different particle sizes.

A systematic mapping study of source code representation for deep learning in software engineering

The usage of deep learning (DL) approaches for software engineering has attracted much attention, particularly in source code modelling and analysis. However, in order to use DL, source code needs to be formatted to fit the expected input form of DL models. This problem is known as source code representation. Source code can be represented via different approaches, most importantly, the tree-based, token-based, and graph-based approaches. We use a systematic mapping study to investigate i detail the representation approaches adopted in 103 studies that use DL in the context of software engineering. Thus, studies are collected from 2014 to 2021 from 14 different journals and 27 conferences. We show that each way of representing source code can provide a different, yet orthogonal view of the same source code. Thus, different software engineering tasks might require different (combinations of) code representation approaches, depending on the nature and complexity of the task. Particularly, we show that it is crucial to define whether the DL approach requires lexical, syntactical, or semantic code information. Our analysis shows that a wide range of different representations and combinations of representations (hybrid representations) are used to solve a wide range of common software engineering problems. However, we also observe that current research does not generally attempt to transfer existing representations or models to other studies even though there are other contexts in which these representations and models may also be useful. We believe that there is potential for more reuse and the application of transfer learning when applying DL to software engineering tasks.

A novel high-performance quadrature rule for BEM formulations

This paper describes a general approach to compute the boundary integral equations that appear when the boundary element method is applied for solving common engineering problems. The proposed procedure consists of a new quadrature rule to accurately evaluate singular and weakly singular integrals in the sense of the Cauchy Principal Value by an exclusively numerical procedure. This procedure is based on a system of equations that results from the finite part of known integrals, that include the shape functions used to approximate the field variables. The solution of this undetermined system of equations in the minimum norm sense provides the weights of the quadrature rule. A MATLAB script to compute the quadrature rule is included as supplementary material of this work. This approach is implemented in a boundary element method formulation based on the Bézier–Bernstein space as an approximation basis to represent both geometry and field variables for verification purposes. Specifically, heat transfer, elastostatic and elastodynamic problems are considered.

Зависимость комплексной гарантированной водоотдачи от регулирующего объема водохранилища

The purpose of the study is to generalize the methodology for solving one of the common engineering problems solved in the development of basin schemes and water management projects, assessment of the parameters of reservoirs of complex purpose. The article analyzes the methodology of construction and practical use ofthe dependence of the complex reservoir guaranteed output onthecalculated hydrological characteristics, the reservoir usable storageand water resourcesprovision for requirements coverage. The role of reservoirs for the development of the integrated use schemesand reservoir water resources using rules to solve the most important water management problems is shown. The engineering and mathematical statement of the problem is formulated. The representativeness of long-term hydrological series by their duration is analyzed, when the relative errors of parameters are put in accordance with the serieslength. It is shown that consideration of the in-series connection (coeffi cient of autocorrelation) and an increase in changeability by 30% leadto the increase in the minimum required duration by several times. On the example of specifi c water objects, the Tsimlyanskiy hydroelectric complex and the cascade of reservoirs of the upper Tobol, the practical application of the generalized method and simulation modeling of the long-term water balance is considered. A variant of water supply scheme to the defi cient areas of Donbass with the involvement of the Severskiy Donets resources for their long-term regulation in the Krasnopavlovsky reservoir (currently not used as a regulating capacity) is presented. Based on the analyzing dependence «capacity-yield», an assessment of additional guaranteed water resources was obtained. With regard to the transboundary section line on the Tobol River, the assessment of the real water yield was obtained by simulation modeling according to the authors’ methodology. The expediency of using simulation and optimization modeling is discussed. The relevance of the topic is noted in connection with the cross-sections topologyand the reservoirsregulating capacity that have been changing for decades. It is rec ommended to discuss the raised issues at conferences and in publications.

Numerical modeling of unsaturated soil behavior considering different constitutive models

Recent advances, not only in fluid flow but also in soil mechanics, have allowed the understanding and forecasting of common engineering problems such as slope stability, soil shrinkage and soil collapse. However, owing to limited access to data or more sophisticated numerical tools, the modeling of soil behavior is usually carried out considering simpler constitutive models which cannot predict some important features of unsaturated soils. This study is focused on the numerical modeling of unsaturated soils, adopting four constitutive models based on theories of elasticity and plasticity. For each model, a numerical simulation of a circular footing resting over a soil that is subject to drying and wetting processes is analyzed. Through the comparison of results, it is possible to highlight the use of more sophisticated constitutive models for unsaturated soil behavior, particularly forecasting the phenomenon of pore collapse during wetting processes.

Levy-based antlion-inspired optimizers with orthogonal learning scheme

Antlion optimization (ALO) is an efficient metaheuristic paradigm that imitates antlion’s foraging behavior when they search for the ants. However, the conventional variant appears to encounter difficulties in avoiding local optima stagnation and slow convergence speed in dealing with complex problems. Hence, there are problems in the performance that need to be mitigated. To alleviate these shortcomings, an improved variant called Levy orthogonal learning ALO is developed, which enhances the efficacy of the core method with orthogonal learning strategy, Levy flight, and primary core mechanisms. To measure the effectiveness of the new method, it is compared with the basic version, variant called Levy flight ALO, and variant called orthogonal learning ALO using thirty benchmark functions from IEEE CEC 2017. Also, it is compared with 15 well-known metaheuristic algorithms. Empirical results have shown the superiority of the proposed algorithm in solving the majority of test functions in terms of solution quality and convergence speed. To further validate the efficacy of the enhanced algorithm, it is applied to common practical engineering problems with constrained and unknown search spaces. The obtained results vividly demonstrate that the proposed algorithm provides satisfactory results for solving these problems.

Alternative design of buried pipelines at active fault crossings using flexible joints

The use of “flexible joints” in buried high-pressure pipelines is examined herein as an effective design technique for the mitigation of Permanent Ground Displacement (PGD) effects due to fault activation. Pipeline joints that are available in the industry today are considered in connection with the needs of high-pressure pipelines in areas of seismic faults. The efficiency of this novel technique is examined through a series of parametric numerical analyses for both strike-slip and normal faults, while its applicability in common engineering problems is examined through an economic-technical comparison with more conventional techniques. It is concluded that the use of flexible joints provides a cost-efficient design method, that can drastically reduce pipeline strains for medium to large fault displacements.

Seismic Vulnerability Analysis of Structure Subjected to Uneven Foundation Settlement

Uneven foundation settlement is one of the common engineering problems in a collapsible loess area. In order to study the influence of uneven foundation settlement on the seismic performance of a structure, the incremental dynamic analysis (IDA) method is used to analyze the seismic vulnerability of the steel structure frame. The differences in the seismic response of the structure in relation to uneven foundation settlement are analyzed. The influences of uneven foundation settlement quantities and various areas of uneven settlement on the seismic response of the structure are discussed. On this basis, the relationship between ground motion intensity and structural failure probability is studied, by changing the magnitude of seismic acceleration peaks. Compared with the unsettled structure, the internal force redistribution of the structure caused by uneven foundation settlement is one of the causes of earthquake damage for some components. The uneven foundation settlement located at the corner of the plane of the structure is likely to cause more serious earthquake damage to the structure. Uneven settlement will cause an increase in storey drift. With the increase in settlement, the seismic damage of the superstructure will be aggravated.

Tire-Pavement Contact Stress Characteristics and Critical Slip Ratio at Multiple Working Conditions

The contact stress distribution of tire-pavement is generally assumed to be uniformly distributed in circles or rectangles in the pavement design. This simplification can solve some common engineering problems, but it neglects two factors including magnitude and direction of the contact stress. The main purpose of this paper is to analyze the contact stress distribution between the bus tire and the pavement under different driving conditions and pinpoint and compare the critical slip ratio during braking and acceleration. First, a tire-pavement simulated contact model is constructed by ABAQUS. Next, we compare, respectively, contact stresses in the vertical, longitudinal, and transverse directions at various rolling conditions and analyze the longitudinal forces at different slip ratios during braking and acceleration. It is observed that the magnitude, direction, and nonuniform distribution of contact stress are affected by the multiple working conditions while the bus is working. Meanwhile, in the braking and acceleration conditions, the longitudinal force grows rapidly as the slip ratio increases, and then grows slowly and at last decreases when the critical slip ratio is reached. However, the critical slip ratio at the time of braking differs from that at the time of acceleration, and the former is smaller than the latter.

How handwriting behaviors during problem solving are related to problem-solving success in an engineering course

If we carefully observe the spatial and temporal organization of students' pen strokes as they solve an engineering problem, can we predict their ability to achieve the correct answer? To address this question, 122 college students were asked to solve exam problems in an engineering course using a smartpen that recorded their writing as digitized timestamped pen strokes. The pen stroke data was used to compute a collection of 10 metrics characterizing various elements of problem-solving fluency including the tendency to progress down the page without revisions, the amount of time with no activity, and the frequency of constructing and using equations. The primary finding is that, on average across 13 different exam problems, these elements of problem-solving process explained 40% of the variance in scores of the correctness of the problem solution. In short, success on generating correct solutions was related to the fluency of the student's problem-solving process (i.e., working sequentially from the top to the bottom of the page, working without detours or long pauses, and working by constructing equations). This work is consistent with the idea that expertise in solving common engineering problems involves being able to treat them like routine rather than non-routine problems.

Applied Dynamics In School And Practice

Mechanical engineering, mechanical engineering technology, and related educational programs are not addressing in a sufficient way the principles associated with applying analytical investigations in solving actual engineering problems. Because of this, graduates do not have the adequate skills required to use the methods of applied dynamics in the process of analyzing mechanical systems. These methods allow one to obtain an understanding of the role of the parameters of a system and to carry out a purposeful control of the values of these parameters with the goal to achieve the desired performance. Engineering and engineering technology programs pay very little attention to addressing these steps. It should be stressed that these programs do not offer a universal straightforward methodology of solving linear differential equations of motion that allow revealing all important interrelationships between the aspects of the engineering problem.
 It is difficult to formulate the reasons why there is such a low interest in applying the analytical approach in order to reveal the interrelationships between decisive aspects of the operational process of an engineering system in order to achieve the desired goal. Actually, there is almost a complete silence with regard to this issue. Hence, we assume that the first reason could be that there is no recognition of the existence of such a problem. In other words, there is no need to apply these analytical methods since these methods are not beneficial. We do not believe that the engineering community supports this reason. It is not a matter of demonstrating factual data that show how many times the theory was helpful. Without the support of the theory we cannot justifiably evaluate the results of our solutions. If we agree that there is problem, then why are there no publications that would stimulate discussions leading toward a solution of the problem?
 Here is the second reason. Until now, engineering programs do not present the straightforward universal theoretically sound methodologies for solving the second order linear differential equations that are vital for mechanical and electrical engineering. Without any suggestions of how to solve this problem, it did not make much sense to begin a discussion. In our opinion, this is why we have silence with the regard to this problem.
 However, it is well known that Laplace Transforms allow solving any linear differential equation of motion. It is justifiable to assume that the main reason why the Laplace Transform methodology is not adopted by learning environments consists in the absence of the majority of tables of Laplace Transform Pairs that are needed for solving differential equations of motion as well as differential equations describing electrical circuits. However, the situation is changed. Current publications comprise the adequate tables that are needed for solving linear differential equations of motion associated with all common mechanical engineering problems.
 Practicing engineers and students need assistance in acquiring the knowledge of composing differential equations of motion. They need certain training in solving these equations using Laplace Transform methodology. Several recommendations are proposed on how to expedite the implementation in academia and in industry of the methods of applied dynamics in solving common mechanical engineering problems.

GPU driven finite difference WENO scheme for real time solution of the shallow water equations

The shallow water equations are applicable to many common engineering problems involving modelling of waves dominated by motions in the horizontal directions (e.g. tsunami propagation, dam breaks). As such events pose substantial economic costs, as well as potential loss of life, accurate real-time simulation and visualization methods are of great importance. For this purpose, we propose a new finite difference scheme for the 2D shallow water equations that is specifically formulated to take advantage of modern GPUs. The new scheme is based on the so-called Picard integral formulation of conservation laws combined with Weighted Essentially Non-Oscillatory reconstruction. The emphasis of the work is on third order in space and second order in time solutions (in both single and double precision). Further, the scheme is well-balanced for bathymetry functions that are not surface piercing and can handle wetting and drying in a GPU-friendly manner without resorting to long and specific case-by-case procedures. We also present a fast single kernel GPU implementation with a novel boundary condition application technique that allows for simultaneous real-time visualization and single precision simulations even on large ( > 2000 × 2000) grids on consumer-level hardware - the full kernel source codes are also provided online at https://github.com/pparna/swe_pifweno3.

Coupled lateral and axial soil-pipe interaction and lateral buckling Part I: Formulation

A general formulation for the two dimensional lateral buckling problem is developed employing classical rod theory. A nonlinear differential system with seven unknowns is derived. Governing equations include a number of previously unaccounted nonlinear terms expressing interaction of various variables representing pipeline geometry and external loads. A rigorous derivation of the transformation of surface loads due to internal and external pressures to line loads revealed some previously unknown limitations on its applicability. Several boundary value problems are formulated corresponding to common pipeline engineering problems. Nonlinear dynamics methods are employed to draw some preliminary results on the behavior of the solutions. It is shown that the trivial solution corresponding to a perfectly straight pipeline experiencing no initial deformation and initial force is unstable.

A review on decision-making methods in engineering design for the automotive industry

ABSTRACTDecision-making methods have proven to be an effective support to engineering design. However, it is proved that very often designers prefer tested procedures and experience-based approaches. Many reasons have been discussed in the literature, dealing with consolidated design habits of people and companies, high cost in terms of time consumption, and lack of tools and knowledge. The paper systematically investigates, through an extended critical review, how decision-making methods can be used by automotive designers to solve the most common engineering problems involved along the design process. In particular, the paper proposes an original classification of the most widely used decision-making methods in engineering design, a match between such techniques with the typical design phases, and a mapping of their application into the automotive field. This research can be considered as a further step to transfer the state-of-the-art knowledge on decision-making methods to the industrial context, establishing a common background for practitioners and researchers.

Учебно-консультационная компьютерная программа для изучения теплообменных процессов

Special software improve the quality of training by processing many transactions in a short period of time, structuring learning information at different levels, organizing presentation of information, and managing interactive communication. The objective is to develop a training-support complex for teaching a course on Thermal Engineering when training specialists for mining and metallurgical industry and solving common engineering problems. The software has the following features: static calculation of heat flow and temperature distribution over the thickness of a flat side-wall, calculation of the side-wall layer thickness (with various boundary conditions); dynamic calculations of temperature redistribution, melting and side-ledge crystallization as one of the side-wall layers, when applying various impacts; use of embedded databases required to perform and verify calculations; Graphical and tabular rendering of the results. The software makes it possible to render the results obtained using color illustrations and animated graphic, provides for conversational interaction between the user and software components, and at the same time, ensures instant control of mastering the material delivered. It can be used for distant learning as well. The software has been implemented in the C ++ Builder environment. The theory of heat transfer and numerical methods of solving ordinary differential equations were used to design the software. The proposed software was trialed during training undergraduate and graduate students of the Institute of Nonferrous Metals and Materials Science of the Siberian Federal University majoring in Metallurgy, Automation of Technological Processes and Production, Management in Technical Systems.

Optimal control problems with incomplete and different integral time domains in the objective and constraints

Optimal control problem with incomplete and different integral time domains is a class of very common practical engineering problems. In traditional way, the integral items are transformed to the transient items and treated as artificial states to reduce the complexity of programming. However, its main disadvantage is time wasting for the considered problems. In this paper, an efficient computational method is therefore proposed for this type of problem, where the integral time domains can be either fixed or variable. By employing the control vector parameterization and a timescaling transformation, the original problem is converted to an approximate optimal parameter selection problem. Moreover, new gradient formulae for the cost and constraint functions are derived. With these gradient formulae, standard gradient-based optimization methods can be easily applied to solve the generated approximate problem. For illustration, three classical numerical examples are tested. The research results, which save 10–22 % of time, show the effectivity of the proposed approach.

A Set of New Benchmark Optimization Problems for Water Resources Management

In this paper, we introduce four new benchmark problems, which are based on rather common optimization issues of water resources management. These problems have the following features: a) adjustable difficulty, to cover a wide range of common engineering problems b) physical background familiar to scientists working on water resources management c) known global optimal solution and known range of values of the objective function d) easy application and e) low computational volume (analytical solution of the respective groundwater flow model). First we calculate the optimal solutions of these problems and then we evaluate their difficulty and their suitability as benchmarking tools, based on theoretical considerations and on the performance of a genetic algorithm and a simulated annealing code in finding their optimal solutions. Results show that the proposed set of benchmark problems is useful for evaluating heuristic optimization codes in the field of water resources management.