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Search Results (466)

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26 pages, 3210 KiB  
Review
NAFLD (MASLD)/NASH (MASH): Does It Bother to Label at All? A Comprehensive Narrative Review
by Consolato M. Sergi
Int. J. Mol. Sci. 2024, 25(15), 8462; https://doi.org/10.3390/ijms25158462 - 2 Aug 2024
Viewed by 419
Abstract
Nonalcoholic fatty liver disease (NAFLD), or metabolic dysfunction-associated steatotic liver disease (MASLD), is a liver condition that is linked to overweight, obesity, diabetes mellitus, and metabolic syndrome. Nonalcoholic steatohepatitis (NASH), or metabolic dysfunction-associated steatohepatitis (MASH), is a form of NAFLD/MASLD that progresses over [...] Read more.
Nonalcoholic fatty liver disease (NAFLD), or metabolic dysfunction-associated steatotic liver disease (MASLD), is a liver condition that is linked to overweight, obesity, diabetes mellitus, and metabolic syndrome. Nonalcoholic steatohepatitis (NASH), or metabolic dysfunction-associated steatohepatitis (MASH), is a form of NAFLD/MASLD that progresses over time. While steatosis is a prominent histological characteristic and recognizable grossly and microscopically, liver biopsies of individuals with NASH/MASH may exhibit several other abnormalities, such as mononuclear inflammation in the portal and lobular regions, hepatocellular damage characterized by ballooning and programmed cell death (apoptosis), misfolded hepatocytic protein inclusions (Mallory–Denk bodies, MDBs), megamitochondria as hyaline inclusions, and fibrosis. Ballooning hepatocellular damage remains the defining feature of NASH/MASH. The fibrosis pattern is characterized by the initial expression of perisinusoidal fibrosis (“chicken wire”) and fibrosis surrounding the central veins. Children may have an alternative form of progressive NAFLD/MASLD characterized by steatosis, inflammation, and fibrosis, mainly in Rappaport zone 1 of the liver acinus. To identify, synthesize, and analyze the scientific knowledge produced regarding the implications of using a score for evaluating NAFLD/MASLD in a comprehensive narrative review. The search for articles was conducted between 1 January 2000 and 31 December 2023, on the PubMed/MEDLINE, Scopus, Web of Science, and Cochrane databases. This search was complemented by a gray search, including internet browsers (e.g., Google) and textbooks. The following research question guided the study: “What are the basic data on using a score for evaluating NAFLD/MASLD?” All stages of the selection process were carried out by the single author. Of the 1783 articles found, 75 were included in the sample for analysis, which was implemented with an additional 25 articles from references and gray literature. The studies analyzed indicated the beneficial effects of scoring liver biopsies. Although similarity between alcoholic steatohepatitis (ASH) and NASH/MASH occurs, some patterns of hepatocellular damage seen in alcoholic disease of the liver do not happen in NASH/MASH, including cholestatic featuring steatohepatitis, alcoholic foamy degeneration, and sclerosing predominant hyaline necrosis. Generally, neutrophilic-rich cellular infiltrates, prominent hyaline inclusions and MDBs, cholestasis, and obvious pericellular sinusoidal fibrosis should favor the diagnosis of alcohol-induced hepatocellular injury over NASH/MASH. Multiple grading and staging methods are available for implementation in investigations and clinical trials, each possessing merits and drawbacks. The systems primarily used are the Brunt, the NASH CRN (NASH Clinical Research Network), and the SAF (steatosis, activity, and fibrosis) systems. Clinical investigations have utilized several approaches to link laboratory and demographic observations with histology findings with optimal platforms for clinical trials of rapidly commercialized drugs. It is promising that machine learning procedures (artificial intelligence) may be critical for developing new platforms to evaluate the benefits of current and future drug formulations. Full article
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15 pages, 7121 KiB  
Article
Design of an Adaptive Height Control System for Sugarcane Harvester Header
by Meiqi Shi, Yanzhou Li, Yingchun Pan, Linfei Lu and Jin Wei
Agronomy 2024, 14(8), 1644; https://doi.org/10.3390/agronomy14081644 - 26 Jul 2024
Viewed by 327
Abstract
This study addresses the issue of low control accuracy and harvesting efficiency resulting from the manual adjustment of the header height during the sugarcane harvesting process in hilly and mountainous regions. An adaptive header height adjustment system was designed and implemented. A test [...] Read more.
This study addresses the issue of low control accuracy and harvesting efficiency resulting from the manual adjustment of the header height during the sugarcane harvesting process in hilly and mountainous regions. An adaptive header height adjustment system was designed and implemented. A test bench for the sugarcane harvester header was designed and constructed, incorporating a LiDAR to measure the ground height at the sugarcane growth point in front, and a draw-wire displacement sensor to monitor the real-time height of the header. I/O ports were allocated, and the control program was developed in the TIA Portal environment. The PLC control system achieves the precise adjustment of the cutting height based on the collected data. The experimental results indicate that the system can quickly respond and adjust the cutting height under complex terrain conditions. When the cutting height into the soil is 0 mm, the adaptive control system’s average cutting height error is 0.28 cm, and the average response time is 2.3 s. When the cutting depth into the soil is 2 cm, the average cutting height error is 0.21 cm, and the average response time is 2.31 s. Full article
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25 pages, 8383 KiB  
Article
Amazon Kit: Proposal for an Innovative Energy Generation and Storage Solution for Sustainable Development of Isolated Communities
by Norah Nadia Sánchez Torres, Jorge Javier Gimenez Ledesma, Marco Roberto Cavallari and Oswaldo Hideo Ando Junior
Sustainability 2024, 16(15), 6280; https://doi.org/10.3390/su16156280 - 23 Jul 2024
Viewed by 473
Abstract
Inequality and the lack of basic services are problems that affect some regions of the Amazon. Among these services, electricity is considered essential for quality of life, but it is still scarce. In some cases, the absence of electricity brings with it concerns [...] Read more.
Inequality and the lack of basic services are problems that affect some regions of the Amazon. Among these services, electricity is considered essential for quality of life, but it is still scarce. In some cases, the absence of electricity brings with it concerns that impact human health, well-being, and development. In this context, this research proposes to develop the sizing of a modular and expandable system for generating electricity with off-grid energy storage to serve single-family homes of river dwellers (from 2 to 8 people) in isolated communities in the Amazon. The research presents and demonstrates the Proknow-C systematic methodology, which shows a systematic approach to rigorous and structured literature reviews. The Amazon Kit concept covers the systems and configurations that can be proposed for single-family homes in the Amazon. The sizing of the Amazon Kit is carried out, ranging from data mapping to estimating consumption per person in homes, followed by the analytical calculation of the solar photovoltaic system—off the grid, considering the basis of the CRESESB portal. SAM (version 2023.12.17) and HOMER PRO® (Version 3.16.2) software is used to simulate and validate the systems. Thus validating the sizing and configuration according to the mapped data and per capita consumption and validating the operability and functionality according to the operating regime, respectively. In this manner, the system depicted in the design and specifications can be adapted to the requirements of single-family dwellings. Furthermore, it offers convenient system maintenance, with an inverter that operates in various configurations (on, off, and zero grid), as well as energy storage for days without sunlight or system maintenance. As a result, the system uses renewable technologies to provide electricity services, filling a significant gap in the literature found in the research. It also offers a sustainable and affordable solution to improve the quality of life and reduce dependence on non-renewable sources. Full article
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13 pages, 2530 KiB  
Review
Lobar and Segmental Atrophy of the Liver: Differential Diagnoses and Treatments
by Federica Ferraina, Alessandro Fogliati, Mauro Alessandro Scotti, Fabrizio Romano, Mattia Garancini and Cristina Ciulli
Livers 2024, 4(3), 320-332; https://doi.org/10.3390/livers4030023 - 15 Jul 2024
Viewed by 377
Abstract
Segmental or lobar liver atrophy is a common but not well-understood clinical condition. Hepatic atrophy can be classified into hepatic atrophy secondary to other pathologies and primary segmental hepatic atrophy, which is a benign intrahepatic lesion (pseudotumor) not associated with any other pathology. [...] Read more.
Segmental or lobar liver atrophy is a common but not well-understood clinical condition. Hepatic atrophy can be classified into hepatic atrophy secondary to other pathologies and primary segmental hepatic atrophy, which is a benign intrahepatic lesion (pseudotumor) not associated with any other pathology. The pathophysiological mechanisms underlying atrophy can be divided into three main situations: obstruction of biliary outflow, obstruction of the systemic venous outflow, and obstruction of incoming portal venous flow. For what may concern secondary hepatic atrophy, there are many pathologies that could underlie this condition, ranging from benign to intrahepatic malignancies, with particular reference to particularly hepatocellular carcinoma and biliary duct carcinoma. An accurate and prompt differential diagnosis between the various forms and causes of atrophy is important for early identification and adequate treatment of underlying pathologies. A comprehensive review of the literature on the etiology and the radiological and histological characteristics of different types of hepatic atrophy is currently unavailable. Therefore, the aim of this review is to summarize the primary and secondary causes of segmental or lobar liver atrophy (excluding forms involving the entire liver parenchyma) and to provide practical tools for clinical and radiological differential diagnosis. Full article
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14 pages, 610 KiB  
Review
The Treatment of Hepatocellular Carcinoma with Major Vascular Invasion
by Tomoko Tadokoro, Joji Tani, Asahiro Morishita, Koji Fujita, Tsutomu Masaki and Hideki Kobara
Cancers 2024, 16(14), 2534; https://doi.org/10.3390/cancers16142534 - 14 Jul 2024
Viewed by 614
Abstract
Vascular invasion of hepatocellular carcinoma involves tumor plugs in the main trunk of the portal vein, bile ducts, and veins, and it indicates poor prognosis. It is often associated with portal hypertension, which requires evaluation and management. Treatment includes hepatic resection, systemic pharmacotherapy, [...] Read more.
Vascular invasion of hepatocellular carcinoma involves tumor plugs in the main trunk of the portal vein, bile ducts, and veins, and it indicates poor prognosis. It is often associated with portal hypertension, which requires evaluation and management. Treatment includes hepatic resection, systemic pharmacotherapy, hepatic arterial infusion chemotherapy, and radiation therapy. Recurrence rates post-hepatic resection are high, and systemic drug therapy often has limited therapeutic potential in patients with a poor hepatic reserve. Single therapies are generally inadequate, necessitating combining multiple therapies with adjuvant and systemic pharmacotherapy before and after hepatectomy. This narrative review will provide an overview of the treatment of hepatocellular carcinoma with vascular invasion. Full article
(This article belongs to the Special Issue Diagnosis and Treatment for Hepatocellular Tumors (Volume II))
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18 pages, 2787 KiB  
Review
Sound Matrix Shaping of Living Matter: From Macrosystems to Cell Microenvironment, Where Mitochondria Act as Energy Portals in Detecting and Processing Sound Vibrations
by Daniela Valenti and Anna Atlante
Int. J. Mol. Sci. 2024, 25(13), 6841; https://doi.org/10.3390/ijms25136841 - 21 Jun 2024
Viewed by 602
Abstract
Vibration and sound are the shaping matrix of the entire universe. Everything in nature is shaped by energy vibrating and communicating through its own sound trail. Every cell within our body vibrates at defined frequencies, generating its peculiar “sound signature”. Mitochondria are dynamic, [...] Read more.
Vibration and sound are the shaping matrix of the entire universe. Everything in nature is shaped by energy vibrating and communicating through its own sound trail. Every cell within our body vibrates at defined frequencies, generating its peculiar “sound signature”. Mitochondria are dynamic, energy-transforming, biosynthetic, and signaling organelles that actively transduce biological information. Novel research has shown that the mitochondrial function of mammalian cells can be modulated by various energetic stimuli, including sound vibrations. Regarding acoustic vibrations, definite types of music have been reported to produce beneficial impacts on human health. In very recent studies, the effects of different sound stimuli and musical styles on cellular function and mitochondrial activity were evaluated and compared in human cells cultured in vitro, investigating the underlying responsible molecular mechanisms. This narrative review will take a multilevel trip from macro to intracellular microenvironment, discussing the intimate vibrational sound activities shaping living matter, delving deeper into the molecular mechanisms underlying the sound modulation of biological systems, and mainly focusing our discussion on novel evidence showing the competence of mitochondria in acting as energy portals capable of sensing and transducing the subtle informational biofields of sound vibration. Full article
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17 pages, 4509 KiB  
Article
Experimental Study on the Mechanical Properties and Health Monitoring Methods of Joints in AAPF
by Zhanqing Xing, Gang Wang and Jing Pang
Buildings 2024, 14(7), 1886; https://doi.org/10.3390/buildings14071886 - 21 Jun 2024
Viewed by 400
Abstract
Aluminum alloy frame is a novel structure system developed in recent years. In this article, the load-bearing performance of the beam-beam joint of the aluminum alloy frame is studied through numerical analysis and experiment and a safety monitoring method is developed. The impacts [...] Read more.
Aluminum alloy frame is a novel structure system developed in recent years. In this article, the load-bearing performance of the beam-beam joint of the aluminum alloy frame is studied through numerical analysis and experiment and a safety monitoring method is developed. The impacts of the arch angle and bolt diameter on the beam-beam joint mechanical characteristics are explored through experiments under vertical load. When the diameter of the bolt was increased, the load-bearing performance of such joint displayed a pattern of first increasing and then decreasing. As the arch angle increased, the load-bearing performance on the joint gradually improved. Based on the experiments, numerical analysis models varying in arch angle were established, and the impacts of arch angles on the stiffness during the yield stage, ultimate load, and elastic stiffness of the aluminum alloy portal frame (AAPF) beam-beam joints were further explored through numerical simulation of the structure under vertical and horizontal loads. When the arching angle was increased, the elastic stiffness and yield stiffness of the beam-beam joint under vertical load showed a pattern of first increasing and then decreasing. When the arching angle was increased, the elastic stiffness and yield stiffness of the beam-beam joint under horizontal load significantly decreased. Based on the mechanical properties, a safety monitoring method for AAPF beam-beam joints based on displacement monitoring and frequency monitoring is proposed. Full article
(This article belongs to the Topic Resilient Civil Infrastructure)
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30 pages, 832 KiB  
Review
Metabolism and Nutrition of L-Glutamate and L-Glutamine in Ruminants
by Guoyao Wu, Fuller W. Bazer, Gregory A. Johnson, M. Carey Satterfield and Shannon E. Washburn
Animals 2024, 14(12), 1788; https://doi.org/10.3390/ani14121788 - 14 Jun 2024
Viewed by 966
Abstract
Although both L-glutamate (Glu) and L-glutamine (Gln) have long been considered nutritionally nonessential in ruminants, these two amino acids have enormous nutritional and physiological importance. Results of recent studies revealed that extracellular Gln is extensively degraded by ruminal microbes, but extracellular Glu undergoes [...] Read more.
Although both L-glutamate (Glu) and L-glutamine (Gln) have long been considered nutritionally nonessential in ruminants, these two amino acids have enormous nutritional and physiological importance. Results of recent studies revealed that extracellular Gln is extensively degraded by ruminal microbes, but extracellular Glu undergoes little catabolism by these cells due to the near absence of its uptake. Ruminal bacteria hydrolyze Gln to Glu plus ammonia and, intracellularly, use both amino acids for protein synthesis. Microbial proteins and dietary Glu enter the small intestine in ruminants. Both Glu and Gln are the major metabolic fuels and building blocks of proteins, as well as substrates for the syntheses of glutathione and amino acids (alanine, ornithine, citrulline, arginine, proline, and aspartate) in the intestinal mucosa. In addition, Gln and aspartate are essential for purine and pyrimidine syntheses, whereas arginine and proline are necessary for the production of nitric oxide (a major vasodilator) and collagen (the most abundant protein in the body), respectively. Under normal feeding conditions, all diet- and rumen-derived Glu and Gln are extensively utilized by the small intestine and do not enter the portal circulation. Thus, de novo synthesis (e.g., from branched-chain amino acids and α-ketoglutarate) plays a crucial role in the homeostasis of Glu and Gln in the whole body but may be insufficient for maximal growth performance, production (e.g., lactation and pregnancy), and optimal health (particularly intestinal health) in ruminants. This applies to all types of feeding systems used around the world (e.g., rearing on a milk replacer before weaning, pasture-based production, and total mixed rations). Dietary supplementation with the appropriate doses of Glu or Gln [e.g., 0.5 or 1 g/kg body weight (BW)/day, respectively] can safely improve the digestive, endocrine, and reproduction functions of ruminants to enhance their productivity. Both Glu and Gln are truly functional amino acids in the nutrition of ruminants and hold great promise for improving their health and productivity. Full article
(This article belongs to the Section Animal Nutrition)
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17 pages, 5937 KiB  
Article
Spatiotemporal Variation of Correlated Color Temperature in the Tunnel Access Zone
by Yangjian Yu, Yuwei Zhang, Shaofeng Wang, Ziyi Guo, Zhikai Ni and Peng Xue
Sustainability 2024, 16(11), 4838; https://doi.org/10.3390/su16114838 - 5 Jun 2024
Cited by 1 | Viewed by 634
Abstract
A scientific and logical tunnel entrance lighting environment is an important guarantee for the safety of drivers entering tunnels as well as an essential element for the sustainable development of the tunnel. At present, most of the highway tunnel entrance lighting environment focuses [...] Read more.
A scientific and logical tunnel entrance lighting environment is an important guarantee for the safety of drivers entering tunnels as well as an essential element for the sustainable development of the tunnel. At present, most of the highway tunnel entrance lighting environment focuses on the road surface luminance and does not consider the variation of correlated color temperatures (CCT) on the driver’s vision in the tunnel access zone. This study analyzes the temporal and spatial variation of the ambient CCT in the driver’s 20° field of view during the approach to the tunnel through field dynamic tests of existing tunnels in the Beijing area. As a result, the CCT received by the driver’s eyes when approaching the tunnel peaks at the midpoint of the tunnel access zone, after which it decreases slowly up to the tunnel portal. Moreover, a calculation model of the CCT outside the tunnel with the solar irradiance, the distance from the tunnel portal, and the CCT of tunnel interior lighting as the input parameters is established. The modeling methodology was validated in a new tunnel, and the calculation model’s average absolute error is within 5%, which could provide guidance for the selection of the tunnel interior lighting CCT and a basis for the design of intelligent control of sustainable lighting systems in tunnels. Full article
(This article belongs to the Section Green Building)
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24 pages, 3899 KiB  
Article
Utility of Water-Based Databases for Underground Water Management: Legal and System Perspective
by Anna Klimach and Elżbieta Zębek
Sustainability 2024, 16(11), 4608; https://doi.org/10.3390/su16114608 - 29 May 2024
Viewed by 510
Abstract
Groundwater is a strategic environmental resource due to its use to human consumption, and therefore requires special protection and monitoring in many databases. In Poland, groundwater data are included in different typical water-related databases such as Hydroportal, Portal of the State Hydrogeological Service [...] Read more.
Groundwater is a strategic environmental resource due to its use to human consumption, and therefore requires special protection and monitoring in many databases. In Poland, groundwater data are included in different typical water-related databases such as Hydroportal, Portal of the State Hydrogeological Service and Portal of the Central Geological Database, which is linked to an integrated real estate information system (IREIS). This article aims to demonstrate how IREIS is used to manage groundwater in Poland. The analysis indicates that shortcomings and gaps are noticeable, e.g., duplication of data and significant lack of data necessary for the implementation of the legal instruments. It is therefore a priority to establish a harmonised permitting and sustainable management of resources by public authorities, supported by an appropriate information and resource system for the EU. There is a need for an increase in the amount of information in databases and a reduction in the number of databases with groundwater information. The results of the analysis of these information systems can provide guidance to other EU countries for more effective groundwater protection and management. Full article
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16 pages, 707 KiB  
Article
Patient Perspectives on Portal-Based Anxiety and Depression Screening in HIV Care: A Qualitative Study Using the Consolidated Framework for Implementation Research
by Jacob A. Walker, Erin M. Staab, Jessica P. Ridgway, Jessica Schmitt, Melissa I. Franco, Scott Hunter, Darnell Motley and Neda Laiteerapong
Int. J. Environ. Res. Public Health 2024, 21(6), 692; https://doi.org/10.3390/ijerph21060692 - 28 May 2024
Viewed by 701
Abstract
Electronic patient portals represent a promising means of integrating mental health assessments into HIV care where anxiety and depression are highly prevalent. Patient attitudes toward portal-based mental health screening within HIV clinics have not been well described. The aim of this formative qualitative [...] Read more.
Electronic patient portals represent a promising means of integrating mental health assessments into HIV care where anxiety and depression are highly prevalent. Patient attitudes toward portal-based mental health screening within HIV clinics have not been well described. The aim of this formative qualitative study is to characterize the patient-perceived facilitators and barriers to portal-based anxiety and depression screening within HIV care in order to inform implementation strategies for mental health screening. Twelve adult HIV clinic patients participated in semi-structured interviews that were audio recorded and transcribed. The transcripts were coded using constructs from the Consolidated Framework for Implementation Research and analyzed thematically to identify the barriers to and facilitators of portal-based anxiety and depression screening. Facilitators included an absence of alternative screening methods, an approachable design, perceived adaptability, high compatibility with HIV care, the potential for linkage to treatment, an increased self-awareness of mental health conditions, the ability to bundle screening with clinic visits, and communicating an action plan for results. The barriers included difficulty navigating the patient portal system, a lack of technical support, stigmatization from the healthcare system, care team response times, and the novelty of using patient portals for communication. The patients in the HIV clinic viewed the use of a portal-based anxiety and depression screening tool as highly compatible with routine HIV care. Technical difficulties, follow-up concerns, and a fear of stigmatization were commonly perceived as barriers to portal use. The results of this study can be used to inform implementation strategies when designing or incorporating portal-based mental health screening into other HIV care settings. Full article
(This article belongs to the Section Behavioral and Mental Health)
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23 pages, 1234 KiB  
Review
The Renin–Angiotensin System in Liver Disease
by Mary S. McGrath and Brian J. Wentworth
Int. J. Mol. Sci. 2024, 25(11), 5807; https://doi.org/10.3390/ijms25115807 - 27 May 2024
Cited by 1 | Viewed by 1089
Abstract
The renin–angiotensin system (RAS) is a complex homeostatic entity with multiorgan systemic and local effects. Traditionally, RAS works in conjunction with the kidney to control effective arterial circulation, systemic vascular resistance, and electrolyte balance. However, chronic hepatic injury and resulting splanchnic dilation may [...] Read more.
The renin–angiotensin system (RAS) is a complex homeostatic entity with multiorgan systemic and local effects. Traditionally, RAS works in conjunction with the kidney to control effective arterial circulation, systemic vascular resistance, and electrolyte balance. However, chronic hepatic injury and resulting splanchnic dilation may disrupt this delicate balance. The role of RAS in liver disease, however, is even more extensive, modulating hepatic fibrosis and portal hypertension. Recognition of an alternative RAS pathway in the past few decades has changed our understanding of RAS in liver disease, and the concept of opposing vs. “rebalanced” forces is an ongoing focus of research. Whether RAS inhibition is beneficial in patients with chronic liver disease appears to be context-dependent, but further study is needed to optimize clinical management and reduce organ-specific morbidity and mortality. This review presents the current understanding of RAS in liver disease, acknowledges areas of uncertainty, and describes potential areas of future investigation. Full article
(This article belongs to the Special Issue The Angiotensin in Human Health and Diseases)
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20 pages, 11454 KiB  
Article
Dynamic Response Study of Overhead Contact System Portal Structure Based on Vehicle–Track–Bridge Coupled Vibration
by Tao Li and Xia Zhao
Energies 2024, 17(11), 2510; https://doi.org/10.3390/en17112510 - 23 May 2024
Viewed by 441
Abstract
In light of the rapid development of electrified railways, the safety and stability of train operations, as well as the catenary’s interaction with current quality, have garnered widespread attention. Electrified train operation with additional track irregularities serves as a principal excitation source within [...] Read more.
In light of the rapid development of electrified railways, the safety and stability of train operations, as well as the catenary’s interaction with current quality, have garnered widespread attention. Electrified train operation with additional track irregularities serves as a principal excitation source within the vehicle–bridge–catenary system, significantly influencing the vibration characteristics of the system. Addressing the aforementioned issues, we first established the vehicle–track dynamics model and the bridge–catenary finite element model based on the principles of coupled dynamics of the vehicle–track system. These models are interconnected using dynamic forces between the wheel and rail. Subsequently, within the vehicle–track coupled system, track random irregularities are introduced as input excitations for the coupled model, and the dynamic response of the system is simulated and solved. Then, the obtained wheel–rail forces are applied to the bridge–catenary coupled system finite element model in the form of time-varying moving load forces. Finally, the dynamic response characteristics of the catenary portal structure under different conditions are determined. Meanwhile, a study on the vibration characteristics of the truss-type pillar portal structure was conducted, and the results were compared with those of existing models. The results indicate that the vertical and lateral forces between the vehicle and track are positively correlated with the speed and irregularity amplitude. Response values such as the derailment coefficient and wheel load reduction rate are within the specified range of relevant standards. The low-order natural resonant frequency of the truss-type pillar structure has, on average, increased by 0.86 compared to the existing pillar structure, which signifies improved stability. Furthermore, under various conditions, the average reductions in maximum displacement and stress response of this pillar structure are 13.2% and 14.19%, respectively, in comparison to the existing pillar structure, rendering it more suitable for practical engineering applications. Full article
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29 pages, 6132 KiB  
Review
Smartphone Prospects in Bridge Structural Health Monitoring, a Literature Review
by Ekin Ozer and Rolands Kromanis
Sensors 2024, 24(11), 3287; https://doi.org/10.3390/s24113287 - 21 May 2024
Viewed by 940
Abstract
Bridges are critical components of transportation networks, and their conditions have effects on societal well-being, the economy, and the environment. Automation needs in inspections and maintenance have made structural health monitoring (SHM) systems a key research pillar to assess bridge safety/health. The last [...] Read more.
Bridges are critical components of transportation networks, and their conditions have effects on societal well-being, the economy, and the environment. Automation needs in inspections and maintenance have made structural health monitoring (SHM) systems a key research pillar to assess bridge safety/health. The last decade brought a boom in innovative bridge SHM applications with the rise in next-generation smart and mobile technologies. A key advancement within this direction is smartphones with their sensory usage as SHM devices. This focused review reports recent advances in bridge SHM backed by smartphone sensor technologies and provides case studies on bridge SHM applications. The review includes model-based and data-driven SHM prospects utilizing smartphones as the sensing and acquisition portal and conveys three distinct messages in terms of the technological domain and level of mobility: (i) vibration-based dynamic identification and damage-detection approaches; (ii) deformation and condition monitoring empowered by computer vision-based measurement capabilities; (iii) drive-by or pedestrianized bridge monitoring approaches, and miscellaneous SHM applications with unconventional/emerging technological features and new research domains. The review is intended to bring together bridge engineering, SHM, and sensor technology audiences with decade-long multidisciplinary experience observed within the smartphone-based SHM theme and presents exemplary cases referring to a variety of levels of mobility. Full article
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40 pages, 22727 KiB  
Article
Image-Aided LiDAR Extraction, Classification, and Characterization of Lane Markings from Mobile Mapping Data
by Yi-Ting Cheng, Young-Ha Shin, Sang-Yeop Shin, Yerassyl Koshan, Mona Hodaei, Darcy Bullock and Ayman Habib
Remote Sens. 2024, 16(10), 1668; https://doi.org/10.3390/rs16101668 - 8 May 2024
Viewed by 917
Abstract
The documentation of roadway factors (such as roadway geometry, lane marking retroreflectivity/classification, and lane width) through the inventory of lane markings can reduce accidents and facilitate road safety analyses. Typically, lane marking inventory is established using either imagery or Light Detection and Ranging [...] Read more.
The documentation of roadway factors (such as roadway geometry, lane marking retroreflectivity/classification, and lane width) through the inventory of lane markings can reduce accidents and facilitate road safety analyses. Typically, lane marking inventory is established using either imagery or Light Detection and Ranging (LiDAR) data collected by mobile mapping systems (MMS). However, it is important to consider the strengths and weaknesses of both camera and LiDAR units when establishing lane marking inventory. Images may be susceptible to weather and lighting conditions, and lane marking might be obstructed by neighboring traffic. They also lack 3D and intensity information, although color information is available. On the other hand, LiDAR data are not affected by adverse weather and lighting conditions, and they have minimal occlusions. Moreover, LiDAR data provide 3D and intensity information. Considering the complementary characteristics of camera and LiDAR units, an image-aided LiDAR framework would be highly advantageous for lane marking inventory. In this context, an image-aided LiDAR framework means that the lane markings generated from one modality (i.e., either an image or LiDAR) are enhanced by those derived from the other one (i.e., either imagery or LiDAR). In addition, a reporting mechanism that can handle multi-modal datasets from different MMS sensors is necessary for the visualization of inventory results. This study proposes an image-aided LiDAR lane marking inventory framework that can handle up to five lanes per driving direction, as well as multiple imaging and LiDAR sensors onboard an MMS. The framework utilizes lane markings extracted from images to improve LiDAR-based extraction. Thereafter, intensity profiles and lane width estimates can be derived using the image-aided LiDAR lane markings. Finally, imagery/LiDAR data, intensity profiles, and lane width estimates can be visualized through a web portal that has been developed in this study. For the performance evaluation of the proposed framework, lane markings obtained through LiDAR-based, image-based, and image-aided LiDAR approaches are compared against manually established ones. The evaluation demonstrates that the proposed framework effectively compensates for the omission errors in the LiDAR-based extraction, as evidenced by an increase in the recall from 87.6% to 91.6%. Full article
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