Hasil untuk "Environmental engineering"

Mark T. Brown, S. Ulgiati

M. Shahbaz, M. Ashraf

H. Sinan Bank, Daniel R. Herber, Thomas H. Bradley

Engineering system design -- whether mechatronic, control, or embedded -- often proceeds in an ad hoc manner, with requirements left implicit and traceability from intent to parameters largely absent. Existing specification-driven and systematic design methods mostly target software, and AI-assisted tools tend to enter the workflow at solution generation rather than at problem framing. Human--AI collaboration in the design of physical systems remains underexplored. This paper presents Design-OS, a lightweight, specification-driven workflow for engineering system design organized in five stages: concept definition, literature survey, conceptual design, requirements definition, and design definition. Specifications serve as the shared contract between human designers and AI agents; each stage produces structured artifacts that maintain traceability and support agent-augmented execution. We position Design-OS relative to requirements-driven design, systematic design frameworks, and AI-assisted design pipelines, and demonstrate it on a control systems design case using two rotary inverted pendulum platforms -- an open-source SimpleFOC reaction wheel and a commercial Quanser Furuta pendulum -- showing how the same specification-driven workflow accommodates fundamentally different implementations. A blank template and the full design-case artifacts are shared in a public repository to support reproducibility and reuse. The workflow makes the design process visible and auditable, and extends specification-driven orchestration of AI from software to physical engineering system design.

Ido Ben-Hertzel, Nathan Blanc, Avishai Meir et al.

Low-grade heat from industrial waste streams, solar-thermal and geothermal, represents a significant energy source currently under-utilized. Phase-Change Thermoacoustic Engines, also known as Wet Thermoacoustic Engines (WTE) consist of a stack (porous medium) sandwiched between two heat exchangers, and an acoustic resonator. In this configuration, the stack walls are wet - soaked with a liquid, whose periodic evaporation and condensation drive acoustic oscillations, augmented by the latent heat transfer. However, implementation at standard acoustic frequencies involves the use of small stack pores ( < 1mm) that are not easy to wet consistently and without clogging. A possible solution is enlarging the stack pore size, which then mandates a reduction of the operating frequency. In an attempt to achieve this, the present work examines the operating characteristics of a water-based standing-wave WTE, coupled with a liquid column - in order to reduce its operating frequency. The results demonstrate a drive ratio of 5% in the wet mode, with an onset temperature difference as low as 20 ∘C, compared to 200 ∘C in the dry mode. This onset temperature difference is lower than any previously reported in similar systems, wet or dry. Operating a thermoacoustic engine under these conditions makes it suitable for various low-temperature heat sources, and the significantly larger pores (1 cm) help prevent issues related to clogging or inconsistent wetting. Experimental results are complemented by a theoretical model, obtaining fair agreement with the results and predicting high efficiency (>20% of the Carnot efficiency) and a power density >10 kW/m3 when operating at higher pressures.

A. Marques, A. Rangel, P. Castro

Mostafa Seifan, A. Berenjian

J. Odling-Smee, D. Erwin, E. Palkovacs et al.

Niraj Gohil, Nawshad Haque, Amgad Elgowainy et al.

Life cycle analysis (LCA) has emerged as a vital tool for assessing the environmental impacts of products, processes, and systems throughout their entire lifecycle. It provides a systematic approach to quantifying resource consumption, emissions, and waste, enabling industries, researchers, and policymakers to identify hotspots for sustainability improvements. By providing a comprehensive assessment of systems, from raw material extraction to end-of-life disposal, LCA facilitates the development of environmentally sound strategies, thereby contributing significantly to sustainable engineering and informed decision-making. Despite its strengths and ubiquitous use, life cycle analysis has not been reconciled with the broader literature in model-based systems engineering and analysis, thus hindering its integration into the design of complex systems more generally. This lack of reconciliation poses a significant problem, as it hinders the seamless integration of environmental sustainability into the design and optimization of complex systems. Without alignment between life cycle analysis (LCA) and model-based systems engineering (MBSE), sustainability remains an isolated consideration rather than an inherent part of the system's architecture and design. The original contribution of this paper is twofold. First, the paper reconciles process-based life cycle analysis with the broader literature and vocabulary of model-based systems engineering and hetero-functional graph theory. It ultimately proves that model-based systems engineering and hetero-functional graph theory are a formal generalization of process-based life cycle analysis. Secondly, the paper demonstrates how model-based systems engineering and hetero-functional graph theory may be used to enhance the spatio-temporal resolution of process-based life cycle analysis in a manner that aligns with system design objectives.

Thomas Thibault, Léa Mosesso, Camille Adam et al.

Designing for sufficiency is one of many approaches that could foster more moderate and sustainable digital practices. Based on the Sustainable Information and Communication Technologies (ICT) and Human-Computer Interaction (HCI) literature, we identify five environmental settings categories. However, our analysis of three mobile OS and nine representative applications shows an overall lack of environmental concerns in settings design, leading us to identify six pervasive anti-patterns. Environmental settings, where they exist, are set on the most intensive option by default. They are not presented as such, are not easily accessible, and offer little explanation of their impact. Instead, they encourage more intensive use. Based on these findings, we create a design workbook that explores design principles for environmental settings: presenting the environmental potential of settings; shifting to environmentally neutral states; previewing effects to encourage moderate use; rethinking defaults; facilitating settings access and; exploring more frugal settings. Building upon this workbook, we discuss how settings can tie individual behaviors to systemic factors.

Zehao Lin

Global climate warming and air pollution pose severe threats to economic development and public safety, presenting significant challenges to sustainable development worldwide. Corporations, as key players in resource utilization and emissions, have drawn increasing attention from policymakers, researchers, and the public regarding their environmental strategies and practices. This study employs a two-way fixed effects panel model to examine the impact of environmental information disclosure on corporate environmental performance, its regional heterogeneity, and the underlying mechanisms. The results demonstrate that environmental information disclosure significantly improves corporate environmental performance, with the effect being more pronounced in areas of high population density and limited green space. These findings provide empirical evidence supporting the role of environmental information disclosure as a critical tool for improving corporate environmental practices. The study highlights the importance of targeted, region-specific policies to maximize the effectiveness of disclosure, offering valuable insights for promoting sustainable development through enhanced corporate transparency.

Myung-Su Yi, Joo-Shin Park

The living quarters (LQ) on jack-up rigs play a critical role in ensuring crew safety and operational functionality under extreme offshore conditions. This study presents a comprehensive structural engineering procedure for the design and analysis of LQ structures, addressing the absence of specific industry standards. The methodology integrates global and local load effects from critical equipment, such as helidecks and lifeboat stations, under harsh environmental conditions during wet towing. A multi-level analysis approach, including finite element analysis (FEA), nonlinear evaluations, and fatigue assessments, was employed to verify structural resilience. The study successfully validates the LQ structures against ultimate limit state (ULS), serviceability limit state (SLS), and accidental limit state (ALS) criteria. The maximum plastic strain observed under green water pressure was 3.8 %, well below the allowable threshold of 15 %, demonstrating adequate safety margins. Fatigue analysis confirmed resistance to vortex-induced vibrations (VIV), ensuring the durability of tubular members. Optimization efforts reduced LQ structural weight by 20 %, enhancing efficiency without compromising safety. The proposed procedure bridges the gap in industry standards, providing a robust framework for designing safer and more reliable LQ structures. This study advances offshore engineering practices by addressing complex loading scenarios and operational challenges, thereby supporting the development of resilient jack-up rigs capable of enduring extreme marine conditions.

S. Tian, Chen Zhang, Danlian Huang et al.

Abstract The growing concerns over the environmental toxicity of sulfonamides (SNs) require immediate action to establish efficient and sustainable processes to address this issue. Adsorption, photodegradation and Fenton/Fenton-like reactions are the most applied processes to remove SNs. However, the adsorption behavior, degradation mechanisms and toxicity of intermediates need further investigation to guide engineering applications. The review focuses on the recent progress and challenges on adsorption, photodegradation and Fenton/Fenton-like techniques for SNs removal. In addition, influences of solution pH and matrix components on adsorption mechanisms are discussed. In particular, the degradation pathway of SNs and toxicity assessment of their intermediates are also analyzed. Finally, conclusions and research gaps in this field are briefly proposed. Publications on this topic have grown exponentially over the last decade. This review provides a unique and comprehensive environmental perspective, as well as the latest knowledge on SNs adsorption and reactive removal by different technologies.

Adrienne J Phillips, R. Gerlach, E. Lauchnor et al.

L. Mann, R. Chang, S. Chandrasekaran et al.

ABSTRACT Problem-based learning (PBL) has a history of producing strong educational results in engineering; however, global society is challenged by highly complex environmental, socio-political and technical problems summarised in the UN Sustainable Development Goals (SDGs). This obliges us to explore educational approaches that address complexity. Yet, confronting complexity is sometimes constrained within PBL structures. This conceptual paper posits practice-based education (PBE) as a whole-of-education approach embracing complexity. We present a PBE framework with three elements: (1) the context of an authentic engineering practice, (2) supporting learners’ agency in the process of becoming professionals, and (3) opportunities to work and learn simultaneously. We make the case for innovative engineering education through the implementation of PBE using the case of the Engineering Practice Academy at Swinburne University of Technology. We detail innovations in student experience as a process of becoming, curriculum and assessment, and provide advice on the application of PBE elsewhere.

G. Long, Y. Gao, You-jun Xie

E. Kristensen

Pengfei Li, Yejia Liu, Jianyi Yang et al.

The sharply increasing sizes of artificial intelligence (AI) models come with significant energy consumption and environmental footprints, which can disproportionately impact certain (often marginalized) regions and hence create environmental inequity concerns. Moreover, concerns with social inequity have also emerged, as AI computing resources may not be equitably distributed across the globe and users from certain disadvantaged regions with severe resource constraints can consistently experience inferior model performance. Importantly, the inequity concerns that encompass both social and environmental dimensions still remain unexplored and have increasingly hindered responsible AI. In this paper, we leverage the spatial flexibility of AI inference workloads and propose equitable geographical load balancing (GLB) to fairly balance AI's regional social and environmental costs. Concretely, to penalize the disproportionately high social and environmental costs for equity, we introduce $L_q$ norms as novel regularization terms into the optimization objective for GLB decisions. Our empirical results based on real-world AI inference traces demonstrate that while the existing GLB algorithms result in disproportionately large social and environmental costs in certain regions, our proposed equitable GLB can fairly balance AI's negative social and environmental costs across all the regions.

Nynke van Uffelen, Lode Lauwaert, Mark Coeckelbergh et al.

In recent years, much research has been dedicated to uncovering the environmental impact of Artificial Intelligence (AI), showing that training and deploying AI systems require large amounts of energy and resources, and the outcomes of AI may lead to decisions and actions that may negatively impact the environment. This new knowledge raises new ethical questions, such as: When is it (un)justifiable to develop an AI system, and how to make design choices, considering its environmental impact? However, so far, the environmental impact of AI has largely escaped ethical scrutiny, as AI ethics tends to focus strongly on themes such as transparency, privacy, safety, responsibility, and bias. Considering the environmental impact of AI from an ethical perspective expands the scope of AI ethics beyond an anthropocentric focus towards including more-than-human actors such as animals and ecosystems. This paper explores the ethical implications of the environmental impact of AI for designing AI systems by drawing on environmental justice literature, in which three categories of justice are distinguished, referring to three elements that can be unjust: the distribution of benefits and burdens (distributive justice), decision-making procedures (procedural justice), and institutionalized social norms (justice as recognition). Based on these tenets of justice, we outline criteria for developing environmentally just AI systems, given their ecological impact.

Cheng-Long Zhou, Yu-Chen Peng, Yong Zhang et al.

We explore a novel approach to achieving anisotropic thermal photon tunneling, inspired by the concept of parity-time symmetry in quantum physics. Our method leverages the modulation of constitutive optical parameters, oscillating between loss and gain regimes. This modulation reveals a variety of distinct effects in thermal photon behavior and dispersion. Specifically, we identify complex tunneling modes through gain-loss engineering, which include thermal photonic defect states and Fermi-arc-like phenomena, which surpass those achievable through traditional polariton engineering. Our research also elucidates the laws governing the evolution of radiative energy in the presence of gain and loss interactions, and highlights the unexpected inefficacy of gain in enhancing thermal photon energy transport compared to systems characterized solely by loss. This study not only broadens our understanding of thermal photon tunneling but also establishes a versatile platform for manipulating photon energy transport, with potential applications in thermal management, heat science, and the development of advanced energy devices.

Ivan Vidakovic, Karin Kornmueller, Daniela Fiedler et al.

Archaeosomes were manufactured from natural archaeal lipids by a microfluidics-assisted single-step production method utilizing a mixture of di- and tetraether lipids extracted from <i>Sulfolobus acidocaldarius.</i> The primary aim of this study was to investigate the exceptional stability of archaeosomes as potential carriers for oral drug delivery, with a focus on powdered formulations. The archaeosomes were negatively charged with a size of approximately 100 nm and a low polydispersity index. To assess their suitability for oral delivery, the archaeosomes were loaded with two model drugs: calcein, a fluorescent compound, and insulin, a peptide hormone. The archaeosomes demonstrated high stability in simulated intestinal fluids, with only 5% of the encapsulated compounds being released after 24 h, regardless of the presence of degrading enzymes or extremely acidic pH values such as those found in the stomach. In a co-culture cell model system mimicking the intestinal barrier, the archaeosomes showed strong adhesion to the cell membranes, facilitating a slow release of contents. The archaeosomes were loaded with insulin in a single-step procedure achieving an encapsulation efficiency of approximately 35%. These particles have been exposed to extreme manufacturing temperatures during freeze-drying and spray-drying processes, demonstrating remarkable resilience under these harsh conditions. The fabrication of stable dry powder formulations of archaeosomes represents a promising advancement toward the development of solid dosage forms for oral delivery of biological drugs.