Engineering Concepts Research Articles

OPTIMIZATION OF ORGANIZATIONAL PROCESSES IN CIVIL ENGINEERING USING LOGISTICS MODELS

Purpose. In accordance with the analyzed problem, there is a need for a more detailed study and justification of the benefits of implementing logistics models to optimize organizational processes in civil engineering. Methodology. To achieve this goal, the article conducts a systematic analysis of organizational processes in civil engineering in terms of logistics approaches. Current trends in the industry, regulations and scientific developments are considered, risks and barriers that may arise when implementing logistics models in the construction industry are analyzed, practical examples of possible use of logistics concepts in civil engineering at different stages of work and when using specific building materials are offered, ways to overcome barriers and stimulate the implementation of logistics models are provided, and an integrated approach to optimizing organizational processes in civil engineering is proposed. Findings. The study has shown that the introduction of logistics models in civil engineering can lead to: significant efficiency improvements, shorter construction time, reduced costs for materials and transportation, improved quality of construction work, reduced environmental impact, rational use of resources, reduced construction waste, increased competitiveness, improved safety, and increased project profitability. Originality. The key principles of development and functioning of logistics models in the context of civil construction are identified: the principle of integration: combining all stages of the construction process into a single logistics system, the principle of resource optimization: minimizing the cost of materials, transport, labor, the principle of flexibility and adaptability: the ability to adapt the logistics model to changing construction conditions. Practical value. The results of the study indicate that the introduction of logistics models in civil engineering is a relevant and promising area for optimizing processes in this sector. The use of logistics can contribute to effective resource management, increase productivity and reduce costs, which is noted by the practical importance of this study.

Natural Concepts and the Economics of Cognition and Communication

AbstractThis article takes a cognitive approach to natural concepts. The aim is to introduce criteria that are evaluated with respect to how they support the cognitive economy of humans when using concepts in reasoning and communicating with them. I first present the theory of conceptual spaces as a tool for expressing the criteria. Then I introduce the central idea that natural concepts correspond to convex regions of a conceptual space. I argue that this criterion has far-reaching consequences as regards natural concepts. Partly following earlier work, I present some other criteria that further delimit the class of natural concepts. One of these is coherence, which does not seem to have been discussed previously. Finally, I show that convexity and other criteria make it possible to ensure that people mean the same thing when they communicate using concepts. Apart from its philosophical interest, the analysis presented in the article will be relevant for tasks of conceptual engineering in artificial systems that work with concepts.

Determination Of Drag And Inertia Coefficients By An Analytical Model

Hard structures like dykes or groins have been recognized for their negative environmental impact and limited durability in the face of climate change (Sutton-Grier et al., 2015). The concept of Shore Soft Engineering (SSE) has allowed ecological considerations to be embedded in the design of coastal protection (Hartig et al., 2011). Among emerging defense structures, nature-based solutions are built with natural materials and rely on physical properties and mechanisms observed in nature. They aim to protect, manage and restore ecosystems while providing some benefit to the human-being and biodiversity (Cohen-Shacham et al., 2016); they offer an interesting alternative to hard structures. However, implementing these solutions in urbanized coastal areas where ecosystems are vulnerable can be challenging. Another alternative approach is using biomimetic solutions, which can provide the functions of natural systems like seagrass, dunes, or coral through robust human-made constructions. Natural habitats exist in a variety of more or less complex forms, ranging from rigid (mangroves, coral) to flexible (seagrass) (Mullarney and Henderson, 2018); and they drive changes in the current profile, in wave dissipation or in sediment motion. Understanding how to mimic these systems, in particular their internal geometry and hydrodynamic effects, is challenging. This complexity makes the development of biomimetic solutions difficult (Perricone et al., 2023). In this context, this study strictly focuses on wave dissipation by flexible systems. Wave dissipation by natural habitats has been extensively studied through laboratory experiments (Houser et al., 2015) and in-situ measurements (Bradley and Houser, 2009). The pioneer analytical model (Dalrymple et al., 1984) depicted aquatic vegetation as rigid cylinders; however, the rigidity assumption fails to capture the inherent flexibility of plants. Alternative strategies emerged to account for this flexibility, such as using an empirical drag coefficient (Mendez and Losada, 2004) or introducing an effective length, representing the length that a rigid cylinder would have to dissipate the same wave height as flexible cylinders (Luhar and Nepf, 2016). However, to define this effective length or an empirical drag coefficient, it is necessary to carry out in-situ measurements. Numerous analytical models based on force balance (Luhar and Nepf, 2016; Leclercq and de Langre, 2018) have been developed to represent the movement of flexible vegetation like seagrass. These models depict the flexible vegetation as a series of segmented rigid stems attached to each other and subjected to oscillating flows. Some models attempt to link stem motion with wave dissipation to integrate this coupling into numerical models (Yin et al., 2022). However, these models still require unknown quantities such as drag and inertial coefficients. The present study aims to develop an analytical model for determining drag and inertial coefficients based solely on the geometry, the structure flexibility and wave forcing. At last, the method could help better represent the dissipation into numerical simulations without the need for prior parametrization.

Mechanics 4.0 and Mechanical Engineering Education

Industry 4.0 is an industrial paradigm that is causing changes in form and substance in factories, companies and businesses around the world and is impacting work and education in general. In fact, the disruptive technologies that frame the Fourth Industrial Revolution have the potential to improve and optimize manufacturing processes and the entire value chain, which could lead to an exponential evolution in the production and distribution of goods and services. All these changes imply that the fields of engineering knowledge must be oriented towards the concept of Industry 4.0, for example, Mechanical Engineering. The development of various physical assets that are used by cyber-physical systems and digital twins is based on mechanics. However, the specialized literature on Industry 4.0 says little about the importance of mechanics in the new industrial era, and more importance is placed on the evolution of Information and Communication Technologies and artificial intelligence. This article presents a frame of reference for the importance of Mechanical Engineering in Industry 4.0 and proposes an extension to the concept of Mechanics 4.0, recently defined as the relationship between mechanics and artificial intelligence. To analyze Mechanical Engineering in Industry 4.0, the criteria of the four driving forces that defined mechanics in the Third Industrial Revolution were used. An analysis of Mechanical Engineering Education in Industry 4.0 is presented, and the concept of Mechanical Engineering 4.0 Education is improved. Finally, the importance of making changes to the educational models of engineering education is described.

Cascaded chiral birefringent media enabled planar lens with programable chromatic aberration

Wavefront control is the fundamental requirement in optical informatics. Planar optics have drawn intensive attention due to the merits of compactness and light weight. However, it remains a challenge to freely manipulate the dispersion, hindering practical applications, especially in imaging. Here, we propose the concept of frequency-synthesized phase engineering to solve this problem. A phasefront-frequency matrix is properly designed to encode different spatial phases to separate frequencies, thus makes arbitrary dispersion tailoring and even frequency-separated functionalization possible. The periodically rotated director endows cholesteric liquid crystal with a spin and frequency selective reflection. Moreover, via presetting the local initial orientation of liquid crystal, geometric phase is encoded to the reflected light. We verify the proposed strategy by cascading the chiral anisotropic optical media of specifically designed helical pitches and initial director orientations. By this means, planar lenses with RGB achromatic, enhanced chromatic aberration and color routing properties are demonstrated. Inch-sized and high-efficient lenses are fabricated with low crosstalk among colors. It releases the freedom of dispersion control of planar optics, and even enables frequency decoupled phase modulations. This work brings new insights to functional planar optics and may upgrade the performance of existing optical apparatuses.

A novel TFET based nanogap high-sensitive biosensor by boosted reliability- new metric for sensitivity definition

This is a detailed report about the proposal of an efficient nanogap dielectrically modulated tunnel field-effect transistor (TFET) biodevice granting a high sensitivity in the detection of the targeted biomolecules while keeping high performance in the realistic situations with boosting the reliability. Two attractive approaches in the cases of the bandgap engineering and charge plasma concept have been suggested for the band energy correction increasing the sensing current and the sensitivity without occurrence possibility of fabrication process related issues as compared to common TFET and PNPN TFET biosensors. The streptavidin, biotin and APTES samples have been selected as typical biomolecules for the sensing performance comparison of the biosensors under the study. Also, the proposed biosensor showed performance superiority for other biomolecules. For the first time, a new metric for measuring sensitivity is proposed to combine both maximum current sensitivity and well-defined average sensitivity in a unique relation named effective sensitivity. This prevents the possible noise impact on the sensitivity of the biosensors since the TFET based biosensors suffer from the low detection current. Defining the effective sensitivity, the proposed biosensor has been evaluated in more realistic conditions including partial hybridization of biomolecules inside the nanogap, trap-assisted-tunneling (TAT) component, neutral/charged biomolecules and biomolecules accumulation in different orientations showing the performance superiority of the proposed biosensor.

THE IMPORTANCE OF ENGLISH FOR SPECIFIC PURPOSES BASED ON THE ENGINEERING STUDENTS’ PERCEPTIONS

English for Specific Purposes (ESP) is garnering significant attention and anticipation for its contribution to the teaching and learning process at the Polytechnic of Road Transportation Safety in Indonesia. Consequently, this study offers valuable insights into the perceptions of cadets at a vocational college regarding the significance of the ESP course within the transportation engineering program. Specifically, this paper aims to explore the cadets' perspective on the role of ESP in their future careers. By conducting a qualitative descriptive study, four types of questionnaires were administered to a total of ninety second-year cadets who are pursuing a major in transport engineering. The findings reveal that the cadets/students recognize the importance of ESP as a crucial subject that supports their future employment prospects. Moreover, they acknowledge the appropriate allocation of time to ESP within their curriculum, recognizing its necessity for their academic success and eventual career advancement. Understanding the importance of ESP is crucial for cadets aspiring to work in the industry. Cadets must have a strong motivation to learn and familiarize themselves with core engineering concepts in order to establish themselves as competitive engineers on a global scale.

Deep insight into regulation mechanism of band distribution in phase junction CdS for enhanced photocatalytic H2 production

An in-depth understanding of structure-activity relationship between the phase constitution and solar-to-hydrogen (STH) conversion efficiency is conducive to guiding the optimization route of targeted photocatalyst candidates, further establishing advanced photocatalytic systems. Herein, based on the concept of phase engineering, we encompassed the crystalline phase of CdS and achieved precise regulation of phase proportion as well as phase boundary width in the phase junction for the first time. The above cooperative effect not only modifies energy band distribution for sufficient redox potentials, but also guarantees the reverse migration orientation of photogenerated carriers in phase junction, thereby endowing photocarriers with a prolonged lifetime. Compared to pure cubic or hexagonal phase (72.6 or 101.1 μmol h−1 g−1), this CdS system with optimized phase junction demonstrates an improved photocatalytic hydrogen evolution activity of 1.04 mmol h−1 g−1 and favorable stability without cocatalyst assistance, which mainly stems from an efficient protons reduction process interacting with long-lived photogenerated electrons. This research explores the mechanism behind phase regulation and its relationship with junction capability, providing a powerful strategy to manipulate crystal phase distribution and paving a feasible avenue for other phase-dependent photocatalysts towards rational design of heterostructures based on different phases in solar energy conversion field.

A rabbit osteochondral defect (OCD) model for evaluation of tissue engineered implants on their biosafety and efficacy in osteochondral repair.

Osteochondral defect (OCD) is a common but challenging condition in orthopaedics that imposes huge socioeconomic burdens in our aging society. It is imperative to accelerate the R&D of regenerative scaffolds using osteochondral tissue engineering concepts. Yet, all innovative implant-based treatments require animal testing models to verify their feasibility, biosafety, and efficacy before proceeding to human trials. Rabbit models offer a more clinically relevant platform for studying OCD repair than smaller rodents, while being more cost-effective than large animal models. The core-decompression drilling technique to produce full-thickness distal medial femoral condyle defects in rabbits can mimic one of the trauma-relevant OCD models. This model is commonly used to evaluate the implant's biosafety and efficacy of osteochondral dual-lineage regeneration. In this article, we initially indicate the methodology and describe a minimally-invasive surgical protocol in a step-wise manner to generate a standard and reproducible rabbit OCD for scaffold implantation. Besides, we provide a detailed procedure for sample collection, processing, and evaluation by a series of subsequent standardized biochemical, radiological, biomechanical, and histological assessments. In conclusion, the well-established, easy-handling, reproducible, and reliable rabbit OCD model will play a pivotal role in translational research of osteochondral tissue engineering.

Aspects of Ammonia as Green Fuel for Propulsion Systems of Inland Water Vessels

Ships are a crucial backbone of the transport system for goods and people. However, the currently utilized fossil fuels require a green replacement. Ammonia produced from green hydrogen is an interesting, carbon‐free green fuel, which has been demonstrated to be promising for maritime applications. Its application under the specific boundary conditions of river ships and other inland water vessels still deserves a closer evaluation. In this work, ammonia as a green fuel for propulsion systems of inland water vessels is evaluated regarding several technological aspects. These include onboard decomposition for hydrogen release, combustion of ammonia–hydrogen mixtures in internal combustion engines and the thermal integration of the different components. To achieve favorable combustion properties of the fuel, a certain share of the ammonia has to be decomposed in an ammonia cracker to produce a mixture of hydrogen and ammonia. First single‐cylinder engine tests show that the combined combustion of ammonia and hydrogen allow an efficient and reliable process for the investigated high‐speed engine concept. Efficiency values of nearly 40% at part load already are achieved. With proper system integration, it is possible to reasonably operate small‐ and medium‐sized ships with ammonia as a green fuel.

New concept for cryogenic gaseous hydrogen-cooled lightweight electric engine

This paper presents parts of the engineering design process and the resulting concept for an electric engine for aviation purpose. Based on the requirement classes mentioned in [1], the concrete requirements resulting from flight operation and the approach of cooling with cryogenic gaseous hydrogen are first compiled. Then, the selected electrical concept of a 500 kW engine is presented, which serves as a basis for identifying the required components and their arrangement. Compared to conventional electric motors, additional components are required. These include hollow coils, structures to distribute the cold gaseous hydrogen to the coils and elements to support the stator laminations with the coils. Materials are then selected for these components with the aim of minimizing weight, and their geometries are predimensioned using analytical approaches and numerical methods. Finally, the individual concepts are synthesized into an overall concept. The result is a compact design for a cryogenically cooled electric motor with a power density of more than 10 kW/kg and a mass of less than 50 kg.

A proposed framework using systems engineering to design human-centric manufacturing systems for novel products to reduce complexity and risk

AbstractThe environment for powertrain production system engineers is changing radically. This initial prescriptive study proposes a systems engineering framework based on two previous case studies which are under review for publication concerning design of battery plants. The framework was developed based on ISO/IEC/IEEE 15288 standard using Concept of Operations and Model-Based Systems Engineering in a workshop setting, with a focus on visualisation to understand the practical and emotional needs of the humans in the system. The framework was validated by twelve senior project members.

A novel concept of active pre-chamber engine with a single injector – The passive main chamber approach

The pre-chamber spark ignited combustion is recognized as one of the most promising concepts utilizing a lean burn combustion approach towards the increase of efficiency and reduction of NOx emissions in spark ignited engines. Numerous investigations indicate the possibility to reduce the engine-out NOx emissions under the regulation limits by using active pre-chamber at very high dilution levels. Regardless of the dilution approach, one of the main challenges is to achieve the proper mixture formation and scavenging of the pre-chamber from residual gases to ensure stable engine operation without misfires. Recent investigations imply that the auxiliary air injection in the pre-chamber might be necessary to ensure stable operation at such highly diluted mixtures, especially if an EGR dilution approach is utilized, further increasing the complexity of such a concept. In this work, a new approach is investigated which can be described as a passive main chamber approach and relies on a single fuel injector supplying both the pre-chamber and the main chamber. Contrary to the passive pre-chamber systems, the injector in this approach is mounted in the pre-chamber, while the main chamber is supplied indirectly through the pre-chamber nozzles. To verify the feasibility and the potential benefits of such an approach, a numerical framework consisting of 3D-CFD and 1D/0D models is applied. The performed study included different pre-chamber variants, previously investigated on an experimental gasoline-fuelled engine, to verify the applicability of such a concept regardless of the pre-chamber geometry. The performed study showed that the proposed concept is a feasible option and, despite the inability to directly control the excess air ratio in the pre-chamber, results with the desired values of λPC ≈ 0.8 at the MBT optimized spark timings. At very lean mixtures (λglobal > 2.0), the average residual gas concentration in the pre-chamber and around the spark plug at the ignition timing is reduced from 10 % and 13 % respectively to 2.5 %, along with a 1.4 percent point increase of indicated efficiency when compared to normal operation. When compared to the reference gasoline fuelled cases, a highest efficiency of 37.7 % is achieved at moderately lean mixture (λglobal ≈ 1.6) and MBT optimized spark timing with NOx levels of 1.41 g/kWh, which represents a 0.7 percent point increase in indicated efficiency but 75 % increase of NOx emissions. At NOx optimized spark timing however (NOx < 0.4 g/kWh), an identical indicated efficiency of 34.7 % is obtained. Overall, the results indicate that with the proposed concept, it is possible to achieve the same scavenging effect as with auxiliary air injection while eliminating the need for both the main chamber injection system and the pre-chamber auxiliary air supply system and without sacrificing the overall performance.

Research on Greening in the Construction of Municipal Garden Project

This paper aims to discuss the greening research in the construction of municipal landscape engineering, in-depth analysis of the importance and role of greening in municipal landscape engineering. This article first introduces the basic concept of municipal garden engineering and its significance in modern city construction, and then focuses on the specific application and effect of greening in the construction of municipal garden engineering. Through case analysis, data comparison and other methods, this paper elaborated the greening to improve the urban environment, improve the quality of life of residents, promote ecological balance and other aspects of the positive role. Finally, the paper summarizes the existing problems and challenges of greening in the construction of municipal garden engineering, and puts forward the corresponding improvement suggestions, which provides useful reference for the future municipal garden greening work.

Design and Fabrication of Automated Counting Machine

Abstract: The design and fabrication of an automatic counting device specifically for wedges are presented in this work. The device effectively counts wedges in a variety of industrial processes by utilizing electronic control systems and precise engineering concepts. The design incorporates a user-friendly interface for smooth operation and sensors for precise detection. In order to assure dependable operation, fabrication entails programming embedded systems and assembling specialized components. For businesses producing wedges, the automated counting machine provides a workable way to improve efficiency and quality assurance.

OPERATION OF PISTON-CYLINDER ASSEMBLY IN GAS ENGINE COMPRESSORS

Gas engine compressors are indispensable components in a wide array of industrial processes, serving to compress gases for various applications such as power generation, manufacturing, and refrigeration. The efficient operation of these compressors is contingent upon the meticulous orchestration of their internal mechanisms, with the cylinder piston assembly standing as a pivotal nexus of functionality. Comprising a dynamic interplay of precision-engineered components—including the cylinder, piston, piston rings, and connecting rod-the assembly plays a foundational role in facilitating the compression process with reliability and efficacy. This article embarks on a comprehensive exploration of the vital elements constituting the cylinder piston assembly, aiming to unravel the intricate nuances of its design, operation, and optimization. By delving into the nuanced functionalities and structural intricacies of each component, this study endeavors to offer a nuanced understanding of the assembly's significance within the broader context of gas engine compressor technology. Furthermore, the article endeavors to dissect the manifold challenges encountered by the cylinder piston assembly during operation, ranging from issues of thermal management to mechanical wear and misalignment. Through a meticulous examination of these challenges, coupled with an analysis of contemporary methodologies and best practices, this study seeks to unearth actionable insights for enhancing the functionality and longevity of gas engine compressors. By distilling complex engineering concepts into practical insights, this article aims to equip industry practitioners, researchers, and stakeholders with the knowledge and tools necessary to navigate the complexities of gas engine compressor technology with confidence and proficiency. Keywords: cylinder piston assembly, piston rings, crankshaft, connecting rod, gas.

How pressure affects costs of power conversion machinery in compressed air energy storage; Part I: Compressors and expanders

This study addresses a critical economic aspect in compressed air energy storage that has not been discussed much in existing literature: the impact of operating pressure on machinery capital cots. It aims to answer whether the cost per unit of power for power conversion systems changes with the maximum storage pressure. Considering that higher storage pressures are associated with greater energy density, enhanced energy storage capabilities and improved system efficiency. This paper helps clarify uncertainties in initial cost estimations for power-generation plants. Effects of operating pressure on the components and overall sizes and consequently costs of power conversion machinery are individually investigated in two parts. Part I encompasses the compressor and expanders, and part II comprehensively discusses the effects of the operating pressure on the costs of heat exchangers. The analysis employs a conceptual engineering approach, revealing that higher intake pressure reduces overall compressor/expander size, leading to cost savings. Additionally, increasing the number of compression stages for higher storage pressures enhances exergy storage cost-effectiveness. To establish an advanced adiabatic CAES plant with a storage pressure of 200 bar instead of 50 bar, there is potential for a 6 % reduction in $/kW expenditure.

Peach Fuzz: Conceptual Engineering of Color Categories

This article explores the products of conceptual engineering in contemporary media communication and mass culture. The analysis examines the mechanisms and communicative consequences of intentionally creating color categories. The shade known as peach fuzz, selected by the Pantone Institute as the color of the year 2024, is used as a case study. It is shown that in the case of the color of the year, the transmission of the conceptual idea involves two channels simultaneously (visual and verbal), each in two different forms. The author notes that the visual channel is used to ostensively present the shade with specific chromatic characteristics and to develope a complex visual image on this basis. Special attention is paid to the verbal channel, which is utilized in the form of intentionally constructed color designations and supporting stories (conceptual myths). It is concluded that from the perspective of color communication, verbal and visual texts serve fundamentally different functions. The visual representation shows how the viewer should see the color, while the verbal explanation clarifies why this shade is needed. It is demonstrated that the image embedded in the color name sets the desired connotation, which can transform the perception of the shade by adding necessary meanings to it. The verbal story defines a cognitive “point of view” for introducing a new category into an existing color system.

Linguistic imposters

Abstract There is a widespread phenomenon that we call linguistic imposters. Linguistic imposters are systematic misuses of expressions that misusers mistake with their conventional usages because of misunderstanding their meaning. Our paper aims to provide an initial framework for theorising about linguistic imposters that will lay the foundation for future philosophical research about them. We focus on the misuses of the expressions ‘grooming’ and ‘critical race theory’ as our central examples of linguistic imposters. We show that linguistic imposters present a distinctive phenomenon by comparing them to some adjacent phenomena, namely conceptual engineering, linguistic hijacking and dogwhistles. We also address four objections about the extensional adequacy of our definition of linguistic imposters. Finally, we argue that, as linguistic imposters spread, they make some inferences featuring misused expressions more cognitively accessible and seemingly socially licensed to misusers and discuss four types of harms that linguistic imposters are conducive to through these effects.

Search Engine for Open Geospatial Consortium Web Services Improving Discoverability through Natural Language Processing-Based Processing and Ranking

The improvement of search engines for geospatial data on the World Wide Web has been a subject of research, particularly concerning the challenges in discovering and utilizing geospatial web services. Despite the establishment of standards by the Open Geospatial Consortium (OGC), the implementation of these services varies significantly among providers, leading to issues in dataset discoverability and usability. This paper presents a proof of concept for a search engine tailored to geospatial services in Switzerland. It addresses challenges such as scraping data from various OGC web service providers, enhancing metadata quality through Natural Language Processing, and optimizing search functionality and ranking methods. Semantic augmentation techniques are applied to enhance metadata completeness and quality, which are stored in a high-performance NoSQL database for efficient data retrieval. The results show improvements in dataset discoverability and search relevance, with NLP-extracted information contributing significantly to ranking accuracy. Overall, the GeoHarvester proof of concept demonstrates the feasibility of improving the discoverability and usability of geospatial web services through advanced search engine techniques.