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Article

18 October 2024

Multi-Objective Distributed Real-Time Trajectory Planning for Gliding Aircraft Cluster

A new combat strategy that enables coordinated operations of gliding aircraft clusters for multi-target strikes imposes higher demands on the coordination, real-time responsiveness, and strike accuracy of gliding aircraft clusters. Due to the high speed and large inertia characteristics of gliding aircraft, traditional trajectory planning methods often face challenges such as long computation times and difficulty in responding to dynamic environments in real-time when dealing with large-scale gliding aircraft clusters. This paper proposes a distributed cooperative trajectory planning method for multi-target strikes by gliding aircraft clusters to address this issue. By introducing a multi-objective distributed real-time trajectory planning approach based on Multi-Agent Deep Deterministic Policy Gradients (MADDPG), the gliding aircraft execute distributed cooperative trajectory planning based on the trained model. Due to its robust real-time performance, the gliding aircraft do not need to recalculate trajectories for different initial positions of the cluster. Simulation results show that the average error between the gliding aircraft cluster and the target point is 2.1 km, with a minimum error of 0.06 km and a hit rate of 96.6%, verifying the significant advantages of this method in real-time planning capability and strike accuracy.

Keywords: Gliding aircraft cluster; Trajectory planning; Multi agent-deep deterministic policy gradient; Distributed collaboration

Article

15 October 2024

Stable Boundaries of Phragmites australis Marsh Development after Peat Mining in a Northern Japan Bog

Since Phragmites australis often develop marshes soon after human disturbances, such as peat mining in bogs, the establishment patterns should be clarified for restoration purposes. The inside and outside boundaries of P. australis marshes were investigated following peat mining in Sarobetsu mire, northern Japan, in 2016 and 2017. The boundaries of marshes did not move during the two years, due mostly to the slow expansion of shoots. Various vegetation types developed outside of the marsh. P. australis coexisted with neither ericaceous nor carnivorous plants, which favor Sphagnum bogs. The succession in the marsh did not progress the original bogs. P. australis dispersed seeds mostly within the marshes, suggesting limited dispersal, and developed transient seed bank. Therefore, seed dispersal (sexual reproduction) and rhizomes (vegetative reproduction) contributed to population maintenance rather than population enlargement during the studied period. Peat moisture was higher in the marsh, whereas photosynthetic active radiation was lower. Water levels did not differ between inside and outside the marshes. Chemical properties in peat water were not different between inside and outside the marshes. Therefore, water chemistry and levels did not adequately explain the marsh development. These results suggest that, for wetland restoration, environmental manipulation is ineffective in reducing P. australis and unpredictable or stochastic events alter the dynamics of P. australis marshes.

Keywords: Mesic grassland; Phragmites australis (common reed); Post-mined peatland; Seed dispersal; Seed bank; Vegetative reproduction

Article

15 October 2024

Binder Jetting 3D Printing Utilizing Waste Algae Powder: A Feasibility Study

This paper reports, for the first time in the literature, a preliminary study to investigate the feasibility of utilizing waste algae powder (byproducts of biofuel manufacturing from algae) in binder jetting 3D printing to produce environmentally friendly products. In this study, the algae powder’s morphology and particle size distribution were characterized using scanning electron microscopy and particle size analyzer, respectively, and the flowability was assessed through apparent density and repose angle. The algae powder successfully printed the cylindrical, cubic, and gyroid parts on a binder jetting 3D printer. Results show that it is feasible to print parts with binder jetting 3D printing utilizing waste algae powder. The use of waste algae powder in additive manufacturing offers a novel approach to upcycling waste algae powder into valuable products for various applications such as packaging and construction.

Keywords: Additive Manufacturing; Binder Jetting 3D Printing; Gyroid Sample; Sustainability; Waste Algae Powder

Review

14 October 2024

Sex and Gender Differences in Liver Fibrosis: Pathomechanisms and Clinical Outcomes

The accumulation of extracellular matrix proteins is the hallmark of liver fibrosis associated with all chronic liver disease (CLD) types. Liver fibrosis results from repeated bouts of liver injury, which trigger the wound-healing response, ultimately disrupting the normal hepatic architecture. Over time, fibrosis can progress to cirrhosis, portal hypertension, liver failure, and hepatocellular carcinoma, worsening patient outcomes. Biological modifiers, such as sex and socio-cultural constructs like gender, influence the development of liver fibrosis through various genetic, hormonal, immunological, metabolic, and lifestyle-related factors, including alcohol consumption, diet, sedentary behavior, and hormonal therapy. Moreover, liver fibrosis is significantly modulated by age, reproductive status, and the etiology of CLD. This review aims to summarize the most well-characterized pathomechanisms underlying sex and gender differences in hepatic fibrogenesis as well as liver-related complications (cirrhosis, portal hypertension, hepatic encephalopathy, liver failure, and hepatocellular carcinoma) and extra-hepatic correlates of liver fibrosis (sarcopenia, cardiovascular disease, diabetes, chronic kidney disease, and dementia) across various types of CLD due to viral-related, autoimmune, drug-induced and metabolic etiologies. Understanding these disease modifiers and their mechanisms is crucial for developing innovative treatment strategies and precision medicine approaches in this field.

Keywords: Age; Cardiovascular disease; Chronic kidney disease; Dementia; diabetes; Estrogen; Genetics; Hepatocellular carcinoma; Portal hypertension, Reproductive status; Sarcopenia; Testosterone

Review

14 October 2024

Photocatalytic Antifouling Coating: From Fundamentals to Applications

With the rapid development of shipping industry, marine vessels frequently suffer from biofouling caused by marine organisms, making the effective prevention of marine biofouling a critical issue. Traditional antifouling coatings, which utilize toxic and harmful substances, pose significant risks to marine ecosystems. Therefore, the development of environmentally sustainable antifouling coatings has become imperative. Photocatalytic antifouling coatings, as an eco-friendly alternative, present a promising solution to these economic, energy, and ecological challenges. This review compares the environmental benefits of photocatalytic antifouling coatings to traditional ones, highlighting the underlying mechanisms of marine biofouling. Additionally, it explores the preparation techniques employed in photocatalytic antifoulant, analyzing the advantages, disadvantages, and potential modifications for photocatalytic coatings. Based on these insights, the future development of photocatalytic antifouling coatings is discussed, aiming to provide valuable references for the exploration of more efficient, broad-spectrum, energy-saving, environmentally friendly, and cost-effective marine antifouling technologies.

Keywords: Biological fouling; Antifouling coatings; Photocatalysis; Environmental benefits

Review

14 October 2024

Characterization, Exploitation and Application of Tibetan Microcrystalline Magnesite

This paper provides a comprehensive account of the properties, development and extensive utilisation of Tibetan microcrystalline magnesite in industry. Tibetan microcrystalline magnesite has become a significant raw material for refractories, high-temperature insulating materials and magnesium chemical materials due to its high purity, low impurity content (mainly Si and Fe elements) and micrometre-sized crystallisation size (2~4 μm). The article presents a detailed analysis of the microstructure of Tibetan microcrystalline magnesite, its thermal decomposition behaviour and the key technologies employed in preparing high-purity magnesium oxide and sintered magnesia through light burning and electrofusion processes. Furthermore, this paper examines the potential applications of Tibetan microcrystalline magnesite in producing high-performance magnesium materials, including activated magnesium oxide, nano-magnesium oxide, and magnesium hydroxide, which are extensively utilized in environmental protection and high-temperature technology. It is demonstrated that the performance of Tibetan microcrystalline magnesite products can be markedly enhanced by optimising the process parameters and modification techniques, thereby further expanding their application prospects in industrial fields. This review offers a theoretical foundation and technical support for effectively utilising Tibetan microcrystalline magnesite, which possesses significant industrial application value and potential.

Keywords: Microcrystalline magnesite; High-purity magnesium oxide; Magnesia; Refractories; Magnesium chemical materials

Article

12 October 2024

Production and Destruction of Plant Organic Matter in Bog Ecosystems in the South of Western Siberia

There are still many gaps in studies of the carbon cycle in northern ecosystems. It is challenging also in the context of climate change. This new study focuses on providing the state of the art data on the dynamics of plant organic matter, namely, the live plant biomass (phytomass), the dead biomass (mortmass), the Net Primary Production (NPP), as well as the rate of decomposition of plant organic matter of the major plant species, contributed to peat deposits. The study was conducted via direct in–situ measurements of different fractions of plant organic matter at a few test sites of oligotrophic pine–dwarf shrub–Sphagnum bogs at a wide geographic gradient (from the middle taiga to the forest-steppe regions in Western Siberia) based on an original methodology of measurements developed by the authors. In general, the five groups of plant species were distinguished in terms of productivity and decomposition rates. The study revealed a strong correlation between the net primary production (NPP) and the rate of decomposition of plant organic matter in pristine northern peatlands: an increase in productivity (NPPs) was basically leading to an increase in rates of decomposition in all plant materials collected in bog ecosystems. The study contributes to a global understanding of patterns and main drivers related to basic set of carbon cycle components in the northern wetland (peatland) ecosystems, their diversity and their spatial distribution.

Keywords: Plant biomass; Net Primary Production (NPP); Destruction of plant organic matter; Carbon sequestration; Wetlands/peatlands; Western Siberia

Article

11 October 2024

Surfactant Protein-C Regulates Alveolar Type 2 Epithelial Cell Lineages via the CD74 Receptor

Background: Deficiency of surfactant protein-C (SPC) increases susceptibility to lung infections and injury, and suppressed expression of SPC has been associated with the severity of acute respiratory distress syndrome (ARDS). Alveolar type 2 epithelial cells (AT2) are critical for maintenance and repair of the lung. However, the role of the SPC in the regulation of AT2 cell lineage and the underlying mechanisms are not completely understood. Methods: This study aimed to investigate the mechanisms by which SPC regulates AT2 lineages. Sftpc−/− mice were used to model the SPC deficiency in ARDS patients. We utilized three-dimensional (3D) organoids to compare AT2 lineage characteristics between wild type (WT) and Sftpc−/− mice by analyzing AT2 proliferation, alveolar type 1 cells (AT1) differentiation and CD74 expression, using colony-formation assay, immunofluorescence, flow cytometry, and immunoblots. Results: The results showed that Sftpc−/− mice demonstrated a reduced AT2 cell population. Influenza A virus subtype H1N1 (H1N1) infected Sftpc−/− mice demonstrated reduced AT2 proliferation and AT1 differentiation. Western blot indicated elevated levels of CD74 protein in AT2 cells of Sftpc−/− mice. Colony-forming efficiency was significantly attenuated in AT2 cells isolated from Sftpc−/− mice compared to the WT controls. Podoplanin (PDPN, a marker of AT1 cells) expression and transient cell count significantly increased in Sftpc−/− organoids. Moreover, siRNA-mediated gene silencing of CD74 in AT2 cells significantly increased AT2 proliferation and AT1 differentiation in Sftpc−/− organoids. Conclusions: This study suggests that SPC regulates AT2 lineage in vitro and in vivo. The SPC might influence AT2 lineage during the lung epithelium repair by activating signaling mechanism involving CD74 receptor.

Keywords: Alveolar type 2 cell; Surfactant protein-C; ARDS; Differentiation; Proliferation; Re-alveolarization

Perspective

10 October 2024

Conceptual Design of Aerostat-Based Autonomous Docking and Battery Swapping System for Extended Airborne Operation

In response to the ever-growing global demand for Unmanned Aerial Vehicles, efficient battery solutions have become vital. This paper proposes a design and concept of an Autonomous Mid Air Battery Swapping System for Vertical Take-Off and Landing Unmanned Aerial Vehicles. The proposed design integrates Aerial Mechatronics, Lighter than Air Systems, and Digital Modelling by leveraging the innovative concept of aerostats for battery swapping. This adaptive and effective technology paves the way for the next generation of autonomous Vertical Take-Off and Landing, ensuring a longer flight time and range. Modern-day technologies have empowered Unmanned Aerial Vehicles to operate autonomously and be remotely controlled, expanding their utility across diverse industries. The enhanced Vertical Take-Off and Landing capabilities include the ability to dock on an aerostat-mounted system, facilitating seamless battery swapping without human intervention and ensuring extended flight duration and operational flexibility. These advancements promise to broaden the applications of Unmanned Aerial Vehicles across various industries.

Keywords: Autonomous; Battery swapping; VTOL; Lighter than air systems; Aerial mechatronics

Review

09 October 2024

A Review of Multi-Domain Urban Energy Modelling Data

Urban energy models (UEMs) simulate energy use at the urban scale and are used to inform urban planning, policy development, infrastructure development, and digital twin monitoring and forecasting. Recent technological improvements have spurred interest in large, multi-domain UEMs, which analyse multiple interconnected parts of these energy systems, such as geography, transport, and buildings. Reviews have focussed on single domains or aspects of UEM data. However, multi-domain UEMs require detailed multi-domain data inputs to provide accurate results. This paper provides a comprehensive review of data requirements and a repository of data-specific information for researchers, including data formats, sources, acquisition methods, bridging methods, and challenges. The review was conducted using academic search engines and the authors’ direct research experience. Domains are characterised by Climate, Geographic, Building, Transportation, Demographics, Energy Networks and Consumption, and Distributed Energy Resources. Additionally, challenges common to multiple sectors are identified, and methods for addressing these are proposed. The paper concludes with a series of recommendations drawing from the general and sector-specific challenges. Overall, a large amount of data exists, but their use by urban energy modellers is limited due to lack of coordination and standardisation, and concerns over privacy and commercial interests. Coordinated public effort is required to overcome these limitations and improve the results of UEMs in the future.

Keywords: Urban energy model; Accessibility; Availability; Building energy model; Urban energy system; Data challenges
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