Hasil untuk "Environmental technology. Sanitary engineering"

Mingzheng Liu, Changhe Li, Yanbin Zhang et al.

Cutting fluid plays a cooling-lubrication role in the cutting of metal materials. However, the substantial usage of cutting fluid in traditional flood machining seriously pollutes the environment and threatens the health of workers. Environmental machining technologies, such as dry cutting, minimum quantity lubrication (MQL), and cryogenic cooling technology, have been used as substitute for flood machining. However, the insufficient cooling capacity of MQL with normal-temperature compressed gas and the lack of lubricating performance of cryogenic cooling technology limit their industrial application. The technical bottleneck of mechanical—thermal damage of difficult-to-cut materials in aerospace and other fields can be solved by combining cryogenic medium and MQL. The latest progress of cryogenic minimum quantity lubrication (CMQL) technology is reviewed in this paper, and the key scientific issues in the research achievements of CMQL are clarified. First, the application forms and process characteristics of CMQL devices in turning, milling, and grinding are systematically summarized from traditional settings to innovative design. Second, the cooling-lubrication mechanism of CMQL and its influence mechanism on material hardness, cutting force, tool wear, and workpiece surface quality in cutting are extensively revealed. The effects of CMQL are systematically analyzed based on its mechanism and application form. Results show that the application effect of CMQL is better than that of cryogenic technology or MQL alone. Finally, the prospect, which provides basis and support for engineering application and development of CMQL technology, is introduced considering the limitations of CMQL.

C. R. Teeneti, T. Truscott, D. Beal et al.

Autonomous underwater vehicles (AUVs) are increasingly used for undersea exploration. The endurance of AUVs is limited by the onboard energy storage among which the battery systems dominate. Various underwater recharging methods are employed to increase the AUV range and autonomy. Currently, contact-based underwater recharging utilizes the wet-mate connector technology that requires a high-precision AUV docking, and is prone to electrical safety issues. To overcome these limitations, underwater wireless recharging techniques for AUVs have been explored in recent years. Wireless charging offers a safe and reliable method for autonomous power transfer between a charging station and a vehicle. This article reviews the state-of-the-art inductive wireless power transfer (IWPT) solutions for underwater applications and discusses the engineering challenges of the IWPT system design. Underwater environmental factors, such as seawater conductivity, temperature, pressure, water currents, and biofouling phenomenon, impose constraints on IWPT systems. A comprehensive review of AUV energy storage systems, docking methods, IWPT system control methods, and compensation networks is presented in this article. Based on the main operational and constructional principles, the AUV IWPT systems are categorized as loosely coupled transformers and resonant IWPT systems. Each of the categories is illustrated through their main design principles and implementations reported in the literature so far. Technical challenges, such as integration of IWPT system into an AUV hull, interoperability, alignment and retention issues, docking station sinking and stability, the design of pressure-tolerant charging electronics, data transfer, and the battery operation in the underwater environment are discussed in this article too. The article is concluded with the best practice overview of designing an IWPT system for AUVs.

Minjun Jo, Yong-Hyun Kim

Tactile toys are handled at close range for prolonged periods, posing potential inhalation risks from volatile organic compounds (VOCs); however, product-specific emission standards are currently absent. We quantified VOCs emitted from nine commercial tactile toys using thermal desorption-gas chromatography-mass spectrometry. Emissions were evaluated using a two-dimensional classification (functional groups and hydrocarbon backbones) and normalized by product mass and surface area. Total VOC concentrations ranged from 24.8 to 775 μg m–3 g–1. Within a given product, increasing the material quantity resulted in highly linear increases in most emitted VOCs (R2 > 0.9), confirming a predictable “dose-with-use” behavior. Across products, class-specific scaling was evident: aromatics scaled with mass (R2 = 0.8234), while sulfur-containing compounds scaled with both mass and surface area (R2 > 0.8362). Stratification by sensory attributes revealed that sticky and sweet-scented products exhibited significant scaling for ethers and alcohols, likely driven by high free volume and surface-localized additives. Hazardous process-related residues, including dimethylformamide and methylene chloride (identified via NIST library search with >95% similarity), were detected at levels that, in screening-level comparisons, significantly exceeded the US EPA Reference Concentrations. These findings characterize the “initial burst” of high-concentration VOCs encountered upon product unpacking, providing a critical benchmark for acute exposure risks. This research underscores the importance of controlling residual solvents and highlights the urgent need for standardized, product-specific emission testing and safety guidelines for tactile toys.

Nidhal Selmi, Jean-michel Bruel, Sébastien Mosser et al.

Decision-making is a core engineering design activity that conveys the engineer's knowledge and translates it into courses of action. Capturing this form of knowledge can reap potential benefits for the engineering teams and enhance development efficiency. Despite its clear value, traditional decision capture often requires a significant amount of effort and still falls short of capturing the necessary context for reuse. Model-based systems engineering (MBSE) can be a promising solution to address these challenges by embedding decisions directly within system models, which can reduce the capture workload while maintaining explicit links to requirements, behaviors, and architectural elements. This article discusses a lightweight framework for integrating decision capture into MBSE workflows by representing decision alternatives as system model slices. Using a simplified industry example from aircraft architecture, we discuss the main challenges associated with decision capture and propose preliminary solutions to address these challenges.

Subhalaxmi Sahoo, Prateeksha Mahamallik, Rahul Das et al.

Photocatalysis is recognized to be one of the most promising ways to address energy and environmental issues by utilizing visible light. Graphitic carbon nitride (g-C3N4), with a moderate band gap (∼2.7 eV) has been the flashpoint in environmental photocatalysis as it can work better under visible light, can be synthesized by a facile synthesis process using low-cost materials, thermally and chemically stable. Still the photocatalytic performance of g-C3N4 is not satisfactory because of certain limitations such as insufficient visible light absorption capacity, low electron-hole separation efficiency, high recombination rate, poor surface area. Introduction of doping, band structure engineering, defecting and designing of heterojunction,composites etc. were investigated to amplify its applications. Among all these modifications, elemental doping is a suitable and successful alternative for the enhancement of the photocatalytic activity by changing the optical and electronic properties. This review emphasizes on advancement and trends of elemental doping and its application on photocatalytic organic pollutant remediation in aqueous medium. The fundamental photocatalytic activity of heterogeneous photocatalysis and specifically g-C3N4-based photocatalysis have been discussed. The benfits of non-metal doping, enhanced photocatalytic performance by doping element, mechanism invloved in doping, advantages of co-doping has been explained. Mono, bi, and tri non-metal doped g-C3N4 and their application for the removal of organic pollutants from water medium by visible light photocatalysis has been summerized. Life cycle assessment (LCA) of photocatalytic system has been highlighted. Future research should focus on the large-scale application of the photocatalysis process considering the economic aspects. A rigorous life cycle assessment for deploying the non-metal doped g-C3N4-based photocatalysis technology for successful commercial application is recommended.

Giacomo Proietti Tocca, V. Agostino, B. Menin et al.

Ida Yuliana, Triawanti, Muhammad Darwin Prenggono et al.

Introduction: Mercury as the source of free radicals can trigger the activation of oxidative stress pathways. With its high toxicity, it can cause hepato-renal injuries. There have been many studies on mercury toxicity in various organs, but there are still few scientific studies that examine the hepato-renal injuries caused by mercury through the oxidative stress pathway. This study was conducted to investigate the triggering of the oxidative stress pathway due to mercury exposure in hepato-renal injuries. Methods: Research using randomized true laboratory experiment method with post-test control group design. The number of samples used was 28 Wistar rats. The research group consisted of 2 groups, control group was given aquadest ad libitum, and intervention group was given water contaminated with mercury per oral once a day (15 kg/WB). The treatment period was 14 consecutive days and on the 15th day, blood samples were taken. Oxidative stress marker was assessed by examining MDA and GPx levels and hepato-renal injuries were assessed by examining liver function (ALT and AST) and kidney function (ureum and creatinine). The collected data were analyzed by independent t-test with 95% confidence level; significant if p>0.05. Results and Discussion: The study found that mercury can trigger the activation of oxidative stress pathways and have an impact on hepato-renal function. Conclusion: Research still needs to be continued to prove that impaired hepato-renal injuries also occur at the cellular histomorphologic and discover other biomolecular mechanisms such as activation of inflammatory pathways that can also cause organ damage.

Jay Lee, Hanqi Su, Dai-Yan Ji et al.

Over the past ten years, the application of artificial intelligence (AI) and machine learning (ML) in engineering domains has gained significant popularity, showcasing their potential in data-driven contexts. However, the complexity and diversity of engineering problems often require the development of domain-specific AI approaches, which are frequently hindered by a lack of systematic methodologies, scalability, and robustness during the development process. To address this gap, this paper introduces the "ABCDE" as the key elements of Engineering AI and proposes a unified, systematic engineering AI ecosystem framework, including eight essential layers, along with attributes, goals, and applications, to guide the development and deployment of AI solutions for specific engineering needs. Additionally, key challenges are examined, and eight future research directions are highlighted. By providing a comprehensive perspective, this paper aims to advance the strategic implementation of AI, fostering the development of next-generation engineering AI solutions.

Anatoly A. Krasnovsky

Chaos engineering reveals resilience risks but is expensive and operationally risky to run broadly and often. Model-based analyses can estimate dependability, yet in practice they are tricky to build and keep current because models are typically handcrafted. We claim that a simple connectivity-only topological model - just the service-dependency graph plus replica counts - can provide fast, low-risk availability estimates under fail-stop faults. To make this claim practical without hand-built models, we introduce model discovery: an automated step that can run in CI/CD or as an observability-platform capability, synthesizing an explicit, analyzable model from artifacts teams already have (e.g., distributed traces, service-mesh telemetry, configs/manifests) - providing an accessible gateway for teams to begin resilience testing. As a proof by instance on the DeathStarBench Social Network, we extract the dependency graph from Jaeger and estimate availability across two deployment modes and five failure rates. The discovered model closely tracks live fault-injection results; with replication, median error at mid-range failure rates is near zero, while no-replication shows signed biases consistent with excluded mechanisms. These results create two opportunities: first, to triage and reduce the scope of expensive chaos experiments in advance, and second, to generate real-time signals on the system's resilience posture as its topology evolves, preserving live validation for the most critical or ambiguous scenarios.

Marina Tal, Rea Lavi, Shari R. Reiss et al.

Qualified professionals in science, technology, engineering, and mathematics (STEM) and STEM education are in increasingly short supply globally. Role models can help increase women’s representation in STEM, both at entry and senior levels. The study objectives were to identify the characteristics of role models in STEM higher education and careers and to investigate the differences in role model characteristics between career stages and between genders. We used a mixed-methods methodology involving a questionnaire and interviews. The participants, 788 alumni and final-year undergraduate and graduate students from a STEM research university, responded to the questionnaire, and ten leading women in STEM professions were interviewed. The questionnaire results indicated that a higher proportion of women than men reported being influenced by a role model during their studies. Seven key characteristics of role models were identified from the open-ended responses and the interviews: ambitious, charismatic, empathic and encouraging, inspiring, knowledgeable, gifted, and professional. The most frequent characteristics women mentioned were empathic and encouraging. The research findings support and align with the social cognitive career theory (SCCT), demonstrating how role modeling, which is part of the environmental theme, boosts intrinsic motivation—part of the personal theme, for individuals in STEM, especially women. These processes impact women’s determination and professional performance—part of the behavioral theme. Based on our findings, to advance toward a STEM workforce characterized by greater fairness, we recommend designing and deploying structured mentoring programs and forums in STEM departments that can provide young women with more role models for success and thus with more hope for success in these fields.

Jiacheng Lu

This paper explores the performance differences between traditional internal combustion engines (ICEs) and hybrid engines. Traditional ICEs have been the cornerstone of automotive technology for over a century, operating by converting chemical energy from burning fuel into mechanical energy. Despite their widespread use, traditional ICEs are significant contributors to air pollution and global warming. In contrast, hybrid engines combine one or more electric motors with a traditional ICE, utilizing battery packs and regenerative braking to enhance fuel efficiency and reduce emissions. As society increasingly adopts hybrid vehicles due to their environmental benefits, understanding the advantages and disadvantages of both engine types is crucial. This study evaluates the energy efficiency, emissions, and power output of traditional and hybrid engines. By analyzing common driving scenarios, this paper provides a comprehensive comparison to inform consumer choices, manufacturing trends, and policies aimed at reducing the automotive industry's carbon footprint and improving economic factors related to fuel consumption. Ultimately, this research aims to contribute to the ongoing dialogue on sustainable transportation and the future of automotive engineering.

Shutian Li, Liu Yang, Jian Fang

ABSTRACT An ecological revetment is a new type that combines natural vegetation with civil engineering technology to establish functions, such as flood control, drainage, ecology, and landscape. Various types of ecological and other bank protection lead to different bank protection effects. Urban river ecological bank protection can effectively prevent bank collapse and promote mutual infiltration between river water and soil and is important for maintaining the balance of the river ecosystem and enhancing the ecological service function of river bank protection. To scientifically and accurately evaluate the ecological protection of riverbanks, this study screened 16 evaluation indicators based on four aspects: structural stability, ecological functionality, landscape suitability, and socio-economic status. A comprehensive evaluation index system for urban river ecological protection was constructed and an urban river ecological protection evaluation model based on the AHP – TOPSIS method was established. The model was used to evaluate the ecological protection of the rivers in the study area. The results revealed that the evaluation value, 0.830, of the self-embedded retaining wall exhibited the best performance among the current slope protection types. In addition, structural stability is a crucial factor in river ecological revetments, and the evaluation results were consistent with the revetment type selected in actual engineering. Therefore, the evaluation system constructed in this study is reasonable and reliable and has strong generalizability. This study provides theoretical guidance for selecting ecological protection banks for future river management projects and has specific references important for academic research and the development of environmental protection banks. GRAPHICAL ABSTRACT

Binnur Görer, Fatma Başak Aydemir

Elicitation interviews are the most common requirements elicitation technique, and proficiency in conducting these interviews is crucial for requirements elicitation. Traditional training methods, typically limited to textbook learning, may not sufficiently address the practical complexities of interviewing techniques. Practical training with various interview scenarios is important for understanding how to apply theoretical knowledge in real-world contexts. However, there is a shortage of educational interview material, as creating interview scripts requires both technical expertise and creativity. To address this issue, we develop a specialized GPT agent for auto-generating interview scripts. The GPT agent is equipped with a dedicated knowledge base tailored to the guidelines and best practices of requirements elicitation interview procedures. We employ a prompt chaining approach to mitigate the output length constraint of GPT to be able to generate thorough and detailed interview scripts. This involves dividing the interview into sections and crafting distinct prompts for each, allowing for the generation of complete content for each section. The generated scripts are assessed through standard natural language generation evaluation metrics and an expert judgment study, confirming their applicability in requirements engineering training.

Viktor Huts, Yevhenii Volynets

During the slaughter and primary processing of animals, production of sausages, canned food, medicines and other products, meat processing plants, meat processing shops, slaughterhouses and other enterprises working with meat raw materials receive a significant amount of raw materials that are considered production waste - non-food raw materials. According to sanitary requirements, it cannot be used for food purposes. It is processed into animal feed or utilized. The amount of non-food meat raw materials ranges from 12...30% of the live weight of animals in meat and fat production during primary processing of livestock and 2...10% in the production of semi-finished products and sausages. It quickly deteriorates, becomes biohazardous, and loses quality. Therefore, if accumulation is necessary, non-food meat raw materials should be stored separately, not in contact with the environment, polluting it and negatively affecting workers. Processed non-food meat products such as industrial fat and dry animal feed also require special storage conditions. Depending on the capacity of the enterprise, the amount of meat raw materials unsuitable for food purposes, the technical equipment of the production, and the economic feasibility of its processing, different technologies and, accordingly, different processing equipment are used. It should ensure high-quality processing of a wide range of different types of meat, and be maximally adapted to the formation of technological lines with closed transport devices. Processing must be carried out in compliance with veterinary and sanitary rules and legal requirements. It is only possible to design modern technological lines for processing meat production waste into animal feed in accordance with the existing environmental safety requirements based on the results of new scientific research and the introduction of innovative engineering developments.

Kelvin Edem Bassey

Hydrokinetic energy devices harness the kinetic energy from flowing water to generate electricity without the need for large dams or reservoirs. This technology represents a significant advancement in renewable energy, offering an environmentally friendly alternative to traditional hydroelectric power. Hydrokinetic devices include various designs such as tidal stream generators, free-flow turbines in rivers and streams, and ocean current turbines. These devices operate by capturing the energy from natural water movements such as tides, river currents, and ocean currents through turbines or other mechanisms that convert kinetic energy into electrical power. The study of hydrokinetic energy devices focuses on their design, development, and deployment in diverse aquatic environments. Key areas of research include optimizing turbine efficiency, improving structural durability, and minimizing environmental impacts. Advances in computational modelling and simulation play a crucial role in this field, allowing researchers to predict device performance under various conditions and to refine designs before physical implementation. Hydrokinetic energy systems offer numerous advantages, including reduced ecological disruption compared to traditional dam-based hydroelectric projects, as they do not require large-scale alterations to watercourses. They also provide a continuous and predictable source of energy, particularly in tidal and ocean current applications, where water movements are regular and reliable. Challenges in the development and deployment of hydrokinetic devices include the harsh underwater environment, which can cause mechanical wear and biofouling, and the need for robust mooring and anchoring systems to withstand strong currents. Additionally, ensuring compatibility with marine ecosystems and minimizing impacts on aquatic life are critical considerations. Overall, hydrokinetic energy devices hold significant promise for expanding the portfolio of renewable energy sources. Continued research and development, supported by advances in materials science, engineering, and environmental science, are essential to overcoming the technical and ecological challenges, making hydrokinetic energy a viable and sustainable option for global energy needs. Keywords: Hydrokinetic Energy, Renewable Energy, Tidal Stream Generators, Free-Flow Turbines.

Yadong Li, Ronghua Xu, Congli Ma et al.

Soil cadmium (Cd) contamination is a global environmental issue facing agriculture. Under certain conditions, the stable Cd that bound to soil particles tend to be remobilized and absorbed into plants, which is seriously toxic to plant growth and threat food safety. Engineering nanomaterials (ENMs) has attracted increasing attentions in the remediation of Cd pollution in soil-plant system due to their excellent properties with nano-scale size. Herein, this article firstly systematically summarized Cd transformation in soil, transport in soil-plant system, and the toxic effects in plants, following which the functions of ENMs in these processes to remediate Cd pollution are comprehensively reviewed, including immobilization of Cd in soil, inhibition in Cd uptake, transport, and accumulation, as well as physiological detoxication to Cd stress. Finally, some issues to be further studied were raised to promote nano-remediation technology in the environment. This review provides a significant reference for the practical application of ENMs in remediation of Cd pollution in soil, and contributes to sustainable development of agriculture.

Changming Li, Shuying Zhao, Ming Li et al.

State Environmental Protection Key Laboratory of Food Chain Pollution Control, School of Ecology and Environment, Beijing Technology and Business University, Beijing, China, State Key Laboratory of Multiphase Complex System, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China, Everbright Environmental Technology (China) Co., Ltd., Incineration Technology Research Institute, Nanjing, China, College of Chemistry, Beijing University of Chemical Technology, Beijing, China, National Engineering Research Center of Sintering and Pelletizing Equipment System, Zhongye Changtian International Engineering Co., Ltd., Changsha, China

Raad Abidmuslim Hraiga, A. Ali, A. Abbas

Improving productivity is one of the most important goals, pursued by economic units, in all the sectors and industries. The key objective is to increase revenues, enhance financial performance and maximize profitability. In general, the Iraqi economic units suffer from weakness and low productivity. Such problems can be overcome by implementing a variety of methods and techniques so that the productivity can be increased while the efficiency and quality can be maximum in the production processes. Several ways exist through which the economic units can become highly energy-efficient and mitigate its carbon emissions. In this background, the aim of the current study is to analyze the theoretical concept of productivity, the factors that affect productivity, its impact upon the overall performance of the economic units and to explore the best practices and methods that are available to improve the productivity in Iraqi industrial sector. The current study tested four hypotheses that focused on increasing productivity, reducing waste, improving profitability, adding competitive advantage to the organization and promoting environmental sustainability. From the study results, it can be concluded that the green process re-engineering is an effective tool to improve productivity and enhance the overall performance of the economic units, including the environmental performance. Further, this process makes use of modern technology, helps in the transition of using environment-friendly materials and the promotion of awareness and training.

О.В. Думанський, Л.М. Михайлова

У статті пропонується експериментально дослідити гофрований конічний випромінювач з метою підтвердження теоретичних розрахунків р Г  коефіцієнта відбивання електромагнітного поля від розкриву досліджуваного гофрованого конічного випромінювача. Дослідження ґрунтуються на впливі електромагнітних полів на фізико-хімічні процеси в біологічних об’єктах. Теоретичні дослідження показали, що для промислового використання необхідний випромінювач з діапазоном частот 30-31 ГГц і діаметром не більше 30 мм, який повинен забезпечити ширину діаграми направленнності в межах 24-30 мм. Для дослідження використовувався виготовлений конічний гофрований опромінювач довжина якого від розкриття до фазового центру дорівнює 21 мм. Діаметр випромінюючого розкриву дорівнює 25 мм. Основні геометричні параметри гофри: h= 2,5 мм, с = 1,25 мм, b= 1,25 мм. Для живлення розглянутого випромінювача використовується перехід з прямокутного хвилеводу перетином 7,2 × 3,4 мм на круглий діаметром 7 мм. Вимірювання проводились на частоті 30 ГГц. Оскільки модуль коефіцієнта відбиття від випромінювача повинен бути близький до нуля, то для точних вимірювань необхідно використовувати метод рефлектометра.

Nivedita Dubey, Subimal Ghosh

Higher warming will affect more regions globally with intensified agricultural and ecological droughts. Higher CO _2 concentration improves vegetation’s water use efficiency (WUE), but its potential to alleviate extreme agricultural and ecological droughts is unclear. India is the second-highest contributor to global greening, having two of the eight global hottest biodiversity hotspots. Here, for the first time, using the CMIP6 earth system models (ESMs), we found an increase in the net vegetation productivity in India at the rate of 10.552 TgC year ^−1 with 1% per year increase in atmospheric CO _2 concentration from 285 ppm to 1140 ppm, contrary to global trends. The improved WUE resulting from carbon fertilization and higher rain under warming will supersede the increased evapotranspiration water loss due to radiative effects. We found that the substantial increase in vegetation productivity in India attributes to plant physiology, and such factor needs to be considered in the drought projections.