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ObjectivesAs an important support for the new power system, hydrogen gas turbines can help reduce carbon emissions and are conducive to grid peak regulation. They are the focus of technological innovation in the global future strategic emerging industries. Many key issues faced by hydrogen blending gas turbine power generation technology from demonstration to commercialization, need to be solved.MethodsH-class gas turbines were taken as the research object, and the strategic planning and demonstration projects of hydrogen blending gas turbine power generation in China and abroad were introduced, and the technology routes of H-class gas turbines of major gas turbine manufacturers were compared. The analysis and suggestion was made from four aspects for the scale application of future hydrogen blending gas turbine power generation technology, including hydrogen source, system transformation, emission impact and hydrogen blending power generation cost.ResultsRenewable energy electrolysis of water to produce hydrogen will be the main source of hydrogen blending gas turbine power generation. In addition, the development of new dry low nitrogen oxide burners, which are suitable for unstable combustion of hydrogen blending, will be the key direction for future hydrogen blending gas turbine system transformation. The higher the hydrogen volume percentage is, the greater the CO2 emission reduction is. However, the NOx emission is on an upward trend. Moreover, there is a risk of exceeding the standard value, and the future cost of hydrogen blending gas turbine power generation can reach the same level as the cost of natural gas power generation.ConclusionsWith the reduction of the cost of large-scale renewable energy hydrogen production, and the implementation of carbon tax and the maturity of hydrogen blending power generation technology, the gas turbine hydrogen blending power generation will gradually enter large-scale application.

This retrospective multicenter study was conducted across 83 intensive care units (ICUs) in 16 cities in Sichuan, China. Critically ill patients diagnosed with heatstroke and lung infections were included in the study. Specimens from the lower respiratory tract were collected for microbiological testing, and the characteristics of the pathogens were described. A total of 462 patients diagnosed with heatstroke-related pulmonary infections were included, 134 patients (29.0%) tested positive for respiratory pathogens. The most frequently isolated strain was Klebsiella pneumoniae (34.3%), followed by Escherichia coli (28.4%), Staphylococcus aureus (20.9%). The results revealed that in the hyperthermic resistance group, there was a higher proportion of Pseudomonas aeruginosa [14(34.1%) vs 11(11.8%), p =0.002] and Stenotrophomonas maltophilia [4(9.8%) vs 1(1.1%), p =0.030] compared to the hyperthermic control group. And a higher proportion of Staphylococcus aureus [27(29.7%) vs 1(2.3%), p <0.001], were obtained during the earlier stages with elevated temperatures. Patients with Klebsiella pneumoniae (38.3 ± 1.9°C), Staphylococcus aureus (38.5 ± 2.2°C), and Pseudomonas aeruginosa (38.7 ± 1.9°C) exhibited a higher temperature environment. Our study provides crucial insights into the lower respiratory tract pathogenesis of heatstroke patients, identifying key pathogens and their temperature-dependent characteristics, thus providing a foundation for future empirical treatment strategies in heatstroke. [ABSTRACT FROM AUTHOR]

BackgroundThe preoperative C-reactive protein/Albumin (CRP/Alb) ratio has been shown to be valuable in predicting the prognosis of patients with certain cancers. The aim of our study is to explore its prognostic value in patients with renal cell carcinoma (RCC).MethodsA retrospective study was performed in 570 RCC patients underwent radical or partial nephrectomy including 541 patients who received full resection of localized (T1-3 N0/+ M0) RCC. The optimal cutoff value of CRP/Alb was determined by the receive operating characteristic (ROC) analysis. The impact of the CRP/Alb and other clinicopathological characteristics on overall survival (OS) and disease-free survival (DFS) was evaluated using the univariate and multivariate Cox regression analysis.ResultsThe optimal cutoff of CRP/Alb ratio was set at 0.08 according to the ROC analysis. Multivariate analysis indicated that CRP/Alb ratio was independently associated with OS of RCC patients underwent radical or partial nephrectomy (hazard ratio [HR]: 1.94; 95% confidence interval [95% CI]: 1.12-3.36; P = 0.018), and DFS of localized RCC patients underwent full resection (HR: 2.14; 95% CI: 1.22-3.75; P = 0.008).ConclusionElevated CRP/Alb ratio was an independent prognostic indicator for poor OS in patients underwent radical or partial nephrectomy and DFS of localized RCC patients underwent full resection. Overall, CRP/Alb may help to identify patients with high relapse risk.

Methidathion (MTDT), a common organophosphorus pesticide with high insecticidal activity, is widely used for pest control. However, the misuse of MTDT leads to widespread residues and endangers human health. Therefore, it is crucial to develop a simple and highly sensitive method for the detection of MTDT residues. Herein, ZIF-90/MnO2/g-C3N4/Fe3O4 composite particles were synthesized: The MnO2 nanosheets could absorb the energy of the excited g-C3N4 to quench the ECL of g-C3N4 while ZIF-90 acted as a mimetic enzyme to catalyze the formation of thiocholine from MTDT. The thiocholine caused the reduction of MnO2 to Mn2+, restoring the ECL signal of g-C3N4. Combined with molecular imprinting technique, an electrochemiluminescence sensor was constructed for the determination of MTDT. The determination range was 1.00 × 10–9 ~ 7.00 × 10–7 g/L, and the detection limit was 6.58 × 10–10 g/L. Structurally similar organophosphorus pesticides showed no cross-reactivity. The method has high sensitivity and specificity, and has been successfully applied to the determination of MTDT residue in fruits with recoveries in the range 93.75% ~ 102.37%. [ABSTRACT FROM AUTHOR]

Background: Malnutrition and systemic inflammatory response are frequently associated with prognosis in patients with several types of cancer, including renal cell carcinoma (RCC). The study is aimed to investigate the ability of preoperative serum albumin to globulin ratio (AGR) to predict the long-term mortality of RCC patients. Methods: The study is a retrospective study of an unselected cohort of 895 RCC patients who underwent a curative radical or partial nephrectomy at the Department of Urology in the Sun Yat-Sen University Cancer Center between January 2000 and December 2012 and had documented preoperative serum total protein and albumin (ALB) levels. The preoperative AGR was calculated as the ratio of ALB to (total protein-ALB) and its association with other clinical indices was assessed using survival analysis. Results: Low preoperative AGR was associated with older population, lower hemoglobin, higher total protein, lower ALB, lower body mass index and advanced stage. The univariate and multivariate Cox analyses demonstrated that preoperative AGR was an independent prognostic indicator of overall survival (OS) (hazard ratio (HR): 0.63, 95% confidence interval (CI): 0.43 to 0.93, P=0.022). In addition, patients with low preoperative AGR at pT1-2, pT3-4, pN0, pN1, pM0 and pM1 stages had significantly shorter OS than patients with high preoperative AGR. Conclusion: Preoperative AGR is a proven objective, reproducible, inexpensive survival predictor of RCC patients following surgical resection and should be considered for routine clinical use.

The prognostic value of serum lipid-profile in renal cell cancer (RCC) remains unknown. The purpose of the study is to explore the association between the serum lipid-profile and RCC patients.The levels of preoperative serum lipid-profile (including cholesterol, triglycerides, high-density lipoprotein-cholesterol [HDL-C], low-density lipoprotein-cholesterol [LDL-C], apolipoprotein A-I [ApoA-I], and apolipoprotein B [ApoB]) were retrospectively performed in 786 patients with RCC. The cutoff values of the lipids were determined by the receiver-operating characteristic (ROC) curve analysis. Univariate and multivariate Cox regression analyses were performed to investigate the prognostic value of serum lipids in RCC.Combined ROC analysis and univariate and multivariate Cox regression analyses, for overall survival (OS), revealed patients with low ApoA-I (

Background: Diabetic cardiomyopathy is a serious complication of obesity with type 2 diabetes and is a major cause of mortality. Metabolic surgery, such as duodenal‐jejunal bypass (DJB), can effectively improve diabetic cardiomyopathy; however, the underlying mechanisms remain elusive. Oxidative stress is one of the pivotal mechanisms of diabetic cardiomyopathy. Our objective was to investigate the effect and potential mechanisms of DJB on oxidative stress in the heart of diabetic cardiomyopathy rats. Methods: High‐fat diet combined with intraperitoneal injection of streptozotocin was used to establish diabetic cardiomyopathy rats. DJB was performed on diabetic cardiomyopathy rats, and high glucose and palmitate were used to simulate diabetic cardiomyopathy in H9C2 cells in vitro. Sera from different groups of rats were used for experiments in vivo and in vitro. Results: DJB effectively improved oxidative stress and activated the adenosine monophosphate (AMP)‐activated protein kinase (AMPK) pathway to increase endothelial nitric oxide synthase (eNOS) phosphorylation level and the expression of antioxidative system‐related proteins and genes in the heart of diabetic cardiomyopathy rats. AMPK agonists and serum from DJB rats activated the AMPK pathway to increase eNOS phosphorylation level and the expression of antioxidative system‐related proteins and genes and decreased the content of reactive oxygen species in H9C2 cells, but this improvement was almost eliminated by the addition of AMPK inhibitors. Conclusions: DJB activates eNOS and enhances the antioxidant system by activating the AMPK pathway—and not solely by improving blood glucose—to improve oxidative stress in the heart of diabetic cardiomyopathy rats. [ABSTRACT FROM AUTHOR]

Pavement texture and skid resistance are pivotal surface features of roadway to traffic safety, especially under wet weather. Engineering interventions should be scheduled periodically to restore these features as they deteriorate over time under traffic polishing. While many studies have investigated the effects of traffic polishing on pavement texture and skid resistance through laboratory experiments, the absence of real-world traffic and environmental factors in these studies may limit the generalization of their findings. This study addresses this research gap by conducting a comprehensive field study of pavement texture and skid resistance under traffic polishing in the real world. A total of thirty pairs of pavement texture and friction data were systematically collected from three distinct locations with different levels of traffic polishing (middle, right wheel path, and edge) along an asphalt pavement in Oklahoma, USA. Data acquisition utilized a laser imaging device to reconstruct 0.01 mm 3D images to characterize pavement texture and a Dynamic Friction Tester to evaluate pavement friction at different speeds. Twenty 3D areal parameters were calculated on whole images, macrotexture images, and microtexture images to investigate the effects of traffic polishing on pavement texture from different perspectives. Then, texture parameters and testing speeds were combined to develop friction prediction models via linear and nonlinear methodologies. The results indicate that Random Forest models with identified inputs achieved excellent performance for non-contact friction evaluation. Last, the friction decrease rate was discussed to estimate the timing of future maintenance to restore skid resistance. This study provides more insights into how engineers should plan maintenance to restore pavement texture and friction considering real-world traffic polishing. [ABSTRACT FROM AUTHOR]

This study used high-temperature melting experiments, optical microscopy, and scanning electron microscopy to investigate the effects of various Ce contents (0 wt.%~0.0165 wt.%) on the microstructure and TiN precipitation behavior in high-titanium steel during slow cooling solidification. The findings show that the microstructure of the solidified steel in each experiment are equiaxed grains at a cooling rate of 0.17 ℃/s. TiN mainly precipitates in the Liquid + δ two-phase region in this experimental steel. CeAlO3 and Ce2O2S precipitate before TiN, and their small lattice misfit with TiN (7.55% and 7.90%, respectively) are the primary cause of their propensity to act as the cores of TiN heterogeneous nucleation. The TiN area density in each experimental steel increases from 38.6 no./mm2 → 61.4 no./mm2 → 89.3 no./mm2 → 105.8 no./mm2 when the Ce content in the steel rises from 0 wt.% → 0.0015 wt.% → 0.0058 wt.% → 0.0165 wt.%. [ABSTRACT FROM AUTHOR]

The high friction surface treatment (HFST) is an effective countermeasure to roadway departure crashes. The field performance of the HFST system was evaluated from seven field monitoring trials on six HFST sites in Oklahoma from 2015 to 2017. HFST sections have statistically significant higher pavement friction and macrotexture in contrast to the adjacent untreated pavements. Meanwhile, distresses including patching, reflective cracking, raveling, and delamination have been observed on these HFST sites. The number of property damage crashes and injured crashes before and after the HFST installation are queried from the Oklahoma safety database. The HFST results in 29% to 100% reductions of annual property damage crashes and 100% reduction of annual injured crashes. The benefit-cost ratios of the HFST sites range from 6.9 to 27.9. In addition, HFST sites constructed with bauxite show higher friction numbers and better polishing resistance performance than sites using the local mine chat aggregates. Key words: high friction surface treatment (HFST), field performance, pavement 3D image, pavement friction, pavement texture, pavement distress, crash reduction, benefit-cost analysis. Le traitement de surface a coefficient de friction elevee (TSCFE) est une mesure efficace contre les accidents causant des sorties de route. Le rendement sur le terrain du systeme TSCFE a ete evalue en se basant sur sept periodes de surveillance sur le terrain sur six sites TSCFE en Oklahoma de 2015 a 2017. Les sections TSCFE presentent une friction et une macro texture statistiquement plus elevees que les chaussees adjacentes non traitees. Entre- temps, on a observe des zones de degradation, y compris des points-a-temps, de la fissuration reflective, de l'arrachement et du delaminage sur ces sites de TSCFE. Le nombre de dommages materiels et de blessures avant et apres l'installation du TSCFE ont ete obtenus de la base de donnees de securite de l'Oklahoma. Le TSCFE donne lieu a une reduction de 29 a 100% des dommages materiels annuels et une reduction de 100% des accidents avec blessures sur un an. Les rapports entre avantages et couts des sites TSCFE varient de 6,9 a 27,9. En outre, les sites TSCFE construits avec de la bauxite presentent des coefficients de friction plus eleves et une meilleure resistance au polissage que les sites utilisant des agregats cherteux de mines locales. [Traduit par la Redaction] Mots-cles: traitement de surface a coefficient de friction eleve (TSCFE), rendement sur le terrain, image tridimensionnelle de la chausee, friction de la chaussee, macro texture, degradation de la chausee, reduction des accidents, analyse couts-benefices., Introduction Background A roadway departure crash is defined as a non-intersection crash that involves a vehicle that crosses an edge line, a center line, or otherwise leaves the traveled way. [...]

Human factors are a primary cause of vehicle accidents. Driver monitoring systems, utilizing a range of sensors and techniques, offer an effective method to monitor and alert drivers to minimize driver error and reduce risky driving behaviors, thus helping to avoid Safety Critical Events (SCEs) and enhance overall driving safety. Artificial Intelligence (AI) tools, in particular, have been widely investigated to improve the efficiency and accuracy of driver monitoring or analysis of SCEs. To better understand the state-of-the-art practices and potential directions for AI tools in this domain, this work is an inaugural attempt to consolidate AI-related tools from academic and industry perspectives. We include an extensive review of AI models and sensors used in driver gaze analysis, driver state monitoring, and analyzing SCEs. Furthermore, researchers identified essential AI tools, both in academia and industry, utilized for camera-based driver monitoring and SCE analysis, in the market. Recommendations for future research directions are presented based on the identified tools and the discrepancies between academia and industry in previous studies. This effort provides a valuable resource for researchers and practitioners seeking a deeper understanding of leveraging AI tools to minimize driver errors, avoid SCEs, and increase driving safety. [ABSTRACT FROM AUTHOR]

Traditional contact and water-based testing devices exhibit some limitations in evaluating pavement skid resistance. This study demonstrates the viability of deep learning (DL) based non-contact pavement skid resistance evaluation using 3D laser imaging technology. Pavement 3D images and friction numbers were collected from 28 field sites in 10 states in the U.S. to cover pavement sections with various texture and friction characteristics. A total number of 28,000 pairs of 3D images and friction numbers were prepared as the database to train and validate the friction prediction model, named as FrictionNet-V, using the convolutional neural network. The input of FrictionNet-V is the 3D pavement image from the left wheel path, and the output is the corresponding friction number ranging from 0.2 to 0.9. Based on the experimental results on 5,600 testing images, FrictionNet-V achieved better performance than other DL models in terms of speed and accuracy. The result demonstrates the potential of highway speed non-contact pavement skid resistance evaluation using high resolution 3D texture images and DL methods at the network level in the future. [ABSTRACT FROM AUTHOR]

Pavement texture is an important surface characteristic for safety evaluation. Through a series of laboratory and field testing, this study presents an automatic non-contact method using high resolution 3D images for accurate and efficient pavement texture evaluation. Firstly, a 3D laser device was applied to capture pavement texture. Subsequently, the 3D texture images were denoised using image processing methods. Then, the 3D seed filling algorithm was developed to calculate mean texture depth (MTD) and mean profile depth (MPD). The computed MTD and MPD values from 3D images showed a good correlation with results of sand patch testing and high repeatability. Further, through the follow-up field testing, the proposed method using 3D images showed better performance in texture evaluation than the 2D texture profiler or sand patch testing. The results indicate it is accurate and efficient to evaluate pavement texture using high resolution 3D images in a non-contact and automatic manner. [ABSTRACT FROM AUTHOR]

Recently, the super-resolution network PT-SRGAN was developed for faster pavement texture measurement using 3D laser technology at 0.1 mm resolution from only six predetermined faster speeds. This paper further introduces an extended application of PT-SRGAN in combination with bicubic interpolation to enhance the low-resolution 3D pavement data collected at any speeds for more flexible practices. The research team collected two datasets on ten field pavement sections: (1) Dataset-1 was the true 0.1 mm 3D texture data collected at very low speeds (<1.5 mph); and (2) Dataset-2 was the low-resolution 3D texture data collected at three faster speeds (7.5, 15, and 30 mph). The efficacy of the extended PT-SRGAN was validated by reconstructing 0.1 mm data from manually downsized low-resolution Dataset-1 and real low-resolution Dataset-2. First, the superior performance of the proposed method was demonstrated by examining two evaluation metrics calculated between ground truth and reconstructed images at different speeds using Dataset-1. Further, seven 3D areal texture parameters were calculated and averaged for reconstructed Dataset-2, and compared with those of Dataset-1 to demonstrate that the proposed method shows promising performance to enhance real low-resolution 3D texture images to 0.1 mm data for any faster pavement texture evaluation. [ABSTRACT FROM AUTHOR]

Various preventive maintenance (PM) treatments have been employed to restore pavement skid resistance for enhanced safety. This paper investigates the effectiveness of PM treatments using panel data analysis (PDA). Panel data analysis investigates the differences of cross-sectional information among treatments, but also the time-series changes within each treatment over time. Panel data with multiple years of friction data for four treatments (thin overlay, slurry seal, crack seal, and chip seal) at various climate, traffic, and pavement conditions are obtained from 255 long term pavement performance (LTPP) testing sections. Both fixed- and random-effects models are developed to evaluate pavement skid resistance performance and to identify the most influencing factors. Results from the PDA models are compared to those from traditional ordinary regression models. Slurry seal is demonstrated to be the most effective treatment. Five factors (precipitation, freezing index, humidity, traffic, and pavement age) are identified to be significant for pavement friction. Fixed-effects panel model is selected for the development of friction prediction models. This study not only demonstrates the capability of PDA for analyzing friction data with cross-sectional and time-series characteristics, but also can assist engineers in selecting the most effective PM treatments for the desired level of skid resistance to reduce traffic crashes. Key words: pavement skid resistance, preventive maintenance, panel data analysis, fixed-effects model, random-effects model. Dans le cadre de cette etude, on examine l'efficacite des traitements d'entretien preventif (EP) en utilisant l'analyse de donnees recueillies au moyen d'un panel (ADP). L'ADP examine les differences d'informations transversales entre les traitements, mais aussi les changements de series temporelles pour chaque traitement au fil du temps. Des donnees de panel avec plusieurs annees de donnees de friction pour quatre traitements (rechargement mince, coulis bitumineux, produit d'etancheite de fissures, enduit d'usure) a differentes conditions de climat, de trafic et de chaussee sont obtenues a partir de 255 sections d'essais de performance a long terme des chaussees (<< LTPP >>). Tant des modeles de panel a effets fixes qu'a effets aleatoires sont developpes et compares aux modeles de regression ordinaires traditionnels. Cinq facteurs (precipitation, indice de gel, humidite, trafic et vieillissement de la chaussee) sont les facteurs les plus importants influant sur la friction de chaussee. Par la suite, le modele de panel a effets fixes est choisi afin de developper des modeles de prediction de friction. Cette etude demontre non seulement la capacite de l'ADP aux fins d'analyser la friction avec des donnees de panel, mais elle peut aussi aider dans la selection des traitements les plus efficaces au niveau de la resistance au derapage desiree et de l'amelioration de la securite. [Traduit par la Redaction] Mots-cles : resistance au derapage des chaussees, entretien preventif, analyse de donnees recueillies au moyen d'un panel, modele a effets fixes, modele a effets aleatoires., Introduction An effective transportation system should facilitate safe and efficient driving environments for vehicles. Sufficient friction (skid resistance) between tire and pavement plays a crucial role to reduce traffic accidents. [...]

It is challenging to collect 3D pavement images with desired resolution for accurate texture measurement at driving speeds with current devices, particularly in the longitudinal direction. This paper presents a novel superresolution technique with recursive generative adversarial network, called Pavement Texture Super Resolution Generative Adversarial Network (PT‐SRGAN), to reconstruct 0.1‐mm pavement 3D image from low‐resolution data for faster texture measurement. With the proposed pseudo‐Laplacian pyramid and an array of learning strategies, the developed PT‐SRGAN reconstructs 0.1‐mm 3D texture images with multiple upscaling factors in longitudinal direction. Combined with the evaluation mask, the proposed method is substantially superior to other methods in terms of three metrics when comparing the image quality of reconstructed 0.1‐mm 3D images against ground truth. The preliminary results indicate that the proposed method enables data collection at driving speeds up to 24 mph to collect 3D pavement images at sub‐mm resolution for faster texture measurement. [ABSTRACT FROM AUTHOR]

Although high friction surface treatment (HFST) has been widely installed in recent years, validation efforts considering various materials, installation ages, environmental conditions, and traffic levels are missing primarily due to lacking of high-speed data collection instruments. Utilizing laser imaging technology and fixed-slip friction tester, this study collects comprehensive pavement surface data at 21 HFST sites in 11 states at highway speeds. Measurements on HFST and untreated pavements are compared to determine the effectiveness of HFST. Multivariate analyses are conducted to investigate the impacts of factors on HFST friction. Average temperature and installation age are identified as the significant factors. The HFST sites constructed using calcined bauxite aggregates exhibit better friction performance than those using flints. Subsequently, friction models are developed to aid highway agencies in managing HFST. Key words: high friction surface treatment (HFST), effectiveness, multivariate analysis, friction models. Bien que les traitements de surface a coefficient de frottement eleve (<< HFST >>) aient ete largement installes ces dernieres annees, il y a une lacune en matiere des efforts de validation prenant en consideration les differents materiaux, les ages des installations, les conditions ambiantes et les niveaux de trafic, et cette lacune est du principalement au manque d'instruments de collecte des donnees a haute vitesse. Dans le cadre de cette etude, en utilisant la technologie de l'imagerie laser et un vehicule de mesure du coefficient de frottement a glissement fixe, on collecte des donnees completes au sujet de la surface du revetement a 21 sites HFST dans 11 Etats, a des vitesses autorisees sur les autoroutes. On compare les mesures prises sur les revetements traites au HFST et ceux non-traites afin de determiner l'efficacite du HFST. Des analyses multivariables sont effectuees afin d'examiner les incidences des differents facteurs sur le frottement HFST. La temperature moyenne et l'age de l'installation sont identifies comme les facteurs significatifs. Les sites HFST construits au moyen d'agregats de bauxite calcinee presentent un meilleur rendement en matiere de frottement que ceux utilisant les silex. Par la suite, on developpe des modeles de frottement pour aider les organismes de voirie a gerer le HFST. [Traduit par la Redaction] Mots-cles : traitement de surface a coefficient de frottement eleve (<< HFST >>), efficacite, analyse multivariable, modeles de frottement., Introduction High friction surfacing treatments (HFST) were first applied in the United Kingdom in the 1960s to maintain pavement skid resistance and reduce the fatalities and injuries from crashes that [...]

Current evaluation of bumps at bridge approaches is limited in scope and performance, and varies in practice at different state DOTs. This study intends to propose a general criterion specifically for bridge approach bump classification and develop a formula for dynamic load allowance (IM) estimation for bridges in Oklahoma. A total of 98 bridges in Oklahoma were studied using recently developed sub-mm 3D laser imaging technology that simultaneously collected inertial profiles, sub-mm 2D/3D images, and right-of-way images at highway speeds for roughness and distress analysis. A three-level criterion that evaluates maximum roughness within an approach or departure slab is established to classify approach bumps into Good, Fair, and Poor conditions. The threshold defined in the criterion considers both the field crew's sensation during data collection and the surface distresses that cause or are associated with different levels of International Roughness Index magnitudes. The development of the formula for bridge IM estimation is based on the established criteria while incorporating the influences of bumps from approach slab and bridge deck. The results of evaluating approach bump and IM of 98 bridges demonstrate the ability of using sub-mm 3D laser imaging technology to evaluate bridge approach bumps and bridge IM in an efficient and effective manner. [ABSTRACT FROM AUTHOR]

The application range of potassium dihydrogen phosphate (KDP) crystals can be expanded by enhancing their surface quality properties. Therefore, a method for controlling the surface-temperature field of various materials was developed to expand the plastic zone to overcome the difficulty in processing KDP crystals. The ductile/brittle transition depth of the KDP crystals was determined using a 38 nm nanoindentation experiment. The nanoscratch experiment revealed the rules of how the transformation depth of the KDP crystals changes with temperatures, and the effect of temperature on the microstructure of the KDP crystals was studied. Finally, KDP crystal surfaces were processed using a UPDFC machine at elevated temperatures. According to our experiments, the surface roughness of the KDP crystal reached 5.275 nm as temperature increased, thus enhancing its surface quality. This method could be applied to other brittle materials. [ABSTRACT FROM AUTHOR]

Although high-friction surface treatments (HFSTs) are a proven efficient countermeasure for the reduction of roadway departure crashes, their long-term pavement performance has yet not been fully understood with large-scale field monitoring. This paper presented and analyzed 3 years of monitoring results on 36 HFST sites located in 12 states in the US ranging from 0 to 11 years in treatment age. Taking the traffic directions and number of lanes at each site into consideration, a total of 65 HFST segments were measured. Onsite data were collected by a Grip Tester for pavement friction, the PaveVision3D laser imaging system for condition evaluation and high-resolution pavement images, and the AMES high-speed profiler for surface texture and roughness. The evolutions of HFST surface characteristics and field performance were evaluated. It was found that most HFST sites continued providing superior friction values compared with the neighboring nontreated surfaces. Cracking and surface delamination were observed as the major failure types on a few sites. The delaminated area exhibited higher roughness values and lower friction numbers. Subsequently, a multivariant friction prediction model was developed to assist in understanding its influencing factors and deterioration trends. Furthermore, a safety performance function was built for crash frequency estimation on HFST sites, through which the benefit of HFST in reducing roadway departure crashes could be further quantified. [ABSTRACT FROM AUTHOR]

This brief presents a high-efficiency shared-aperture multiple antenna system. Unlike general shared-aperture antennas, the proposed antenna system with the size of $0.384 {\times } 0.384 {\times } 0.171 {\mathrm {\lambda }} ^{3}$ makes high reuse the aperture in the two respective frequency bands, and the antenna structures of the two bands can each generate positive mutual enhancement for their radiating characteristics in the two bands. The flat Luneburg lens can realize beam steering capability for mm-wave antenna from 25.5 to 29.5 GHz with the gain of 19.3 dBi and improve the wide-angle scanning matching impedance for the Sub-6 GHz antenna from 3.2 to 3.45 GHz with the gain of 6.2 dBi. Meanwhile, as the radiating patch of the Sub-6 GHz antenna, the meta-surface can reduce the focal distance of the lens and maintain the high gain of the mm-wave antenna. Hence, a compact antenna system can achieve beam steering capabilities (up to 112°) in the Sub-6 GHz band and (up to 56°) mm-wave band with high gain, respectively. And the port isolation of the proposed antenna system between two frequency bands is generally better than 25 dB and even up to 40 dB at the Sub-6 GHz band. As reported in the simulated and measured results in a linear array, the antenna system shows good radiating performance with a dual-polarization state. Hence, the proposed multiple antenna system is a good candidate for 5G applications because of the high-efficiency, beam steering with high gain and full 5G band. [ABSTRACT FROM AUTHOR]

A wideband and wide beam‐width dual‐polarization with a low‐profile and simple structure is presented in this letter. The proposed antenna comprises two pairs of bending plates, the feed part that includes the probe and the copper disk, and two series of feeding networks. A couple of the bending plates can be used to form the horizontal and vertical currents to broaden the antenna's beam width. To radiate a symmetrical wide beam pattern, a series feeding network is applied to guarantee a symmetrical current distribution on the bending plates. Therefore, the proposed wide beam capability has been analyzed and verified with a dual‐polarization antenna. A low‐profile dual‐polarization antenna is demonstrated, which can realize the half‐power beam‐width more than 180° and 100° in the E‐ and H‐plane in the whole operating frequency band (22.3%), respectively. Furthermore, the port isolation is lower than −35 dB in the most frequency band. The prototype is fabricated and characterized, yielding good performance within the overall operational bandwidth. The measured results align very well with the simulated results. The proposed wideband antenna is a promising candidate for wireless communication systems because of the dual‐polarization and wide beam‐width. [ABSTRACT FROM AUTHOR]

Simultaneous pixel‐level detection of multiple distresses and surface design features on complex asphalt pavements is a critical challenge in intelligent pavement survey. This paper proposes a deep‐learning model named ShuttleNet to provide an efficient solution for this challenge by implementing robust semantic segmentation on asphalt pavements. The proposed ShuttleNet aims at repeating the encoding–decoding round freely or even endlessly such that the contexts at different resolution levels can be learned and integrated many times for enhanced latent representations. Additionally, a new and efficient connection method called memory connection is also proposed in the paper and deployed in the ShuttleNet model to provide shortcut connections between successive encoding–decoding rounds. The proposed memory connection can partially or entirely carry the decoded information at different resolution levels into the next encoding–decoding round. Pairing 3D pavement images with 2D pavement images, the proposed ShuttleNet model is applied to detect multiple distresses and surface design features on asphalt pavements simultaneously, including pavement cracks, potholes, sealed cracks, patches, markings, expansion joints, and the pavement background. Experimental results demonstrate that the mean F‐measure and mean intersection‐over‐union attained by the recommended architectural variation of the proposed ShuttleNet model on 1500 testing image pairs are 92.54% and 0.8657 respectively. According to the performance comparisons using both private and public datasets, the proposed ShuttleNet model can yield a noticeably higher detection accuracy, compared with four state‐of‐the‐art models for semantic segmentation. [ABSTRACT FROM AUTHOR]

Traditionally, pavement safety performance in terms of texture, friction, and hydroplaning speed are measured separately via different devices with various limitations. This study explores the feasibility of using a novel 0.1 mm 3D Safety Sensor for pavement safety evaluation in a non-contact and continuous manner with a single hardware sensor. The 0.1 mm 3D images were collected for pavement safety measurement from 12 asphalt concrete (AC) and Portland cement concrete (PCC) field sites with various texture characteristics. The results indicate that the Safety Sensor was able to measure pavement texture data as traditional devices do with better repeatability. Moreover, pavement friction numbers can be estimated using 0.1 mm 3D data via the proposed 3D texture parameters with good accuracy using an artificial neural network, especially for asphalt pavement. Lastly, a case study of pavement hydroplaning speed prediction was performed using the Safety Sensor. The results demonstrate the potential of using ultra high-resolution 3D imaging to measure pavement safety, including texture, friction, and hydroplaning, in a non-contact, continuous, and accurate manner. [ABSTRACT FROM AUTHOR]

A dual-polarized phased array antenna is presented with wide-angle scanning capability in this article. To improve the mutual coupling in the array, a current cancellation method (CCM) is proposed by changing the current distribution on the excited unit to induce a pair of the canceled currents on the adjacent unit. Meanwhile, this current distribution broadens the beamwidth of the unit in the array. Besides, the proposed method can also optimize the array unit size and achieve a small inter-unit distance for wide-angle scanning capability. A low-profile dual-polarization antenna operating in the bandwidth from 4.4 to 5.0 GHz is designed as a linear array and a planar array to verify the proposed method. Regardless of the linear array or planar array, the mutual coupling in the array is below −19 dB, which is better than that in conventional arrays. Meanwhile, the antenna unit in the array can radiate a wide-beam pattern. Two arrays can scan over ±60° for both polarizations. Within the scanning range, the realized gain reduction is less than 3 dB and the sidelobe level is lower than −7.5 dB. To verify the performance, two array antenna prototypes are fabricated and tested. The experimental results agree well with the simulation. [ABSTRACT FROM AUTHOR]

The pavement friction has been recognised as a critical contributor to traffic safety and an important pavement functional characteristic. The sideway force coefficient routine investigation machine (SCRIM) has been used in many studies for pavement friction evaluation. However, this device is costly to purchase and run which limits its accessibility to many transportation agencies. This study explores an artificial neural network model to predict the sideway force coefficient (SFC) from SCRIM using pavement micro- and macro-texture information. On the selected field site, pavement texture was evaluated by a digital sand patch tester and a portable high-resolution 3D laser scanner, while pavement friction was measured using a SCRIM. The obtained high-resolution 3D texture data was decomposed into micro- and macro-textures via discrete Fourier transform and Butterworth filters. Then, height, feature, and hybrid texture parameters were calculated to characterise pavement 3D texture at the micro- and macro-levels. Next, the obtained pavement texture parameters were used to predict SFC through linear and neural network models. The neural network model, including pavement micro- and macro-texture parameters, shows better performance than other models and is adequate to predict SFC. Besides, pavement micro-texture shows more contribution to SFC than macro-texture. [ABSTRACT FROM AUTHOR]