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This review article offers an in-depth analysis of cooperative motion planning and control in aerial-ground autonomous systems, emphasizing their methods and applications. It explores the integration of unmanned aerial vehicles (UAVs) and unmanned ground vehicles (UGVs), focusing on their synchronized planning and control mechanisms that enable efficient task execution in various settings, such as disaster response, environmental monitoring, and urban surveillance. The article addresses the motion planning strategies, and control mechanisms, while also highlighting the challenges and future trends in this domain. It serves as a comprehensive resource, shedding light on both the potentials and limitations of these systems, thereby providing valuable insights for researchers and practitioners in the field of autonomous systems. [ABSTRACT FROM AUTHOR]

• Ballast derived from different parent rocks were reinforced with CR. • Degradation of ballast subjected to various impact loads was measured. • The big dataset was employed to train and test the machine learning models. • Parent rock type was the most influential parameter based on ML models. Parent rock strength and crumb rubber modification are two critical mechanical parameters that significantly decide the ballast layer degradation subjected to train dynamic loading. Using machine learning to predict ballast degradation considering these two parameters is helpful for deciding ballasted track maintenance cycle. In the current study, the ballast degradation process data (variables: parent rock types, loading types, ballast gradations and compositions of crumb rubber-ballast mixture) were used to train machine learning models. The drop-weight impact loading tests were performed to simulate different train dynamic loadings. Two well-established machine learning models, i.e., random forest (RF) and support vector regression (SVR) were trained and verified, to more effectively assess the importance of these variables. The results from the validated machine learning models confirm that the parent rock type is the most influential parameter, followed by the loading type (applied stress level), to control and predict the degradation of the ballast-CR mixture. The experimental assessment reveals that although the incorporation of CR suppresses degradation across all characterized rock types, the improvement in performance of the ballast-CR specimen against degradation is more noticeable for high-strength parent rock subjected to a considerable stress level. Meanwhile, this positive influence is also observed for ballast of weaker strength when the applied stress level is low. [ABSTRACT FROM AUTHOR]

• Quantified assessment of individual ballast degradation based on 3D particle images. • Illustration of ballast breakage type and quantified using surface area change. • Improvements in ballast surface texture quantification with 3D particle images. • Reuse of waste rubber in railway engineering (ballast layer). Higher speed, more freight and frequent maintenance increase ballast degradation and reduce the ballast lifespan. To reduce ballast degradation, crumb rubber used as buffering aggregates in ballast bed is relatively unexplored and needs more studies, because using it has the advantage of reusing the waster rubber and absorbing the noises. The effects of crumb rubber (CR) size and percentage on ballast degradation reduction is studied in this paper, and the optimal CR size and percentage are proposed. Three CR size ranges are utilised, i.e., 3 ∼ 5 mm, 10 ∼ 15 mm and 20 ∼ 25 mm, and the percentages are 0, 10, 20 and 30% by weight. Three kinds of ballast material with two size ranges are utilised. The deteriorated ballast particles were generated using Los Angeles Abrasion (LAA) tests, and the ballast degradation was evaluated with the 3D image analysis. The results indicate that ballast abrasion can be alleviated by adding the CR, while the CR has few influences on the ballast breakage. When CR size is close to ballast particle size, the effects of degradation reduction are not obvious. The corner and edge loss are the main types of ballast abrasion, although different ballast materials significantly influence the abrasion type and degree. Most importantly, the image analysis method is proved to have the ability to present ballast degradation process and has great potential for further degradation-related studies. [ABSTRACT FROM AUTHOR]

Akebia stem has long been used extensively as a rare Chinese herbal medicine. The three most significant Akebia medicinal species are Akebia quinata (Thunb.) Decne. (A. quinata), Akebia trifoliata (Thunb.) Koidz. (A. trifoliata), and Akebia trifoliata (Thunb.) Koidz. var. Australis (Diels) Rehd. (A. trifoliata. var). They have significant therapeutic effects and are widely used in the pharmaceutical and cosmetics industries. Only a few studies compared their chemical differences and antioxidant activities. To better demonstrate each species' characteristics and antioxidant properties, the ultra-performance liquid chromatography coupled with quadrupole Orbitrap mass spectrometry (UPLC-Q-Orbitrap/MS)-based metabolomics was applied to investigate the chemome diversity of three Akebia species. Their antioxidant activities were evaluated by DPPH and ABTS assays. In total, 65 different metabolites were identified, including 5 phenolic acids, 2 phenylpropanoids, 4 lignan glycosides, and 54 triterpenoid saponins. The different aglycone types of triterpenoid saponins were found to be the component differences between the three Akebia species. The chemical composition of A. trifoliata and A. trifoliata. var is similar. The 2-(3,4-dihydroxyphenyl)-ethyl-O-β- d -glucopyranoside has been found only in A. quinata. In contrast, the triterpenoid saponins akemisaponin B, akemisaponin D, oleanolic-acid-3-O-arabinopyranosyl-28-O-glucopyranosyl-glucopyranosyl-rhamnopyranosyl-arabinopyranosyl, akemisaponin C and saponin P j1 have been found A. trifoliata and A. trifoliata. var. As a result, these six compounds can be considered marker compounds that distinguish three Akebia species. The antioxidant activities results indicated that the antioxidants of three Akebia species were the same in different antioxidative test systems. A. trifoliata (IC 50 : 2.28–6.97 mg·mL−1) and A. trifoliata. var (IC 50 : 2.09–6.87 mg·mL−1) showed 2–3 times higher antioxidant activity than A. quinata (IC 50 : 5.56–11.21 mg·mL−1). This study reveals the antioxidant activity differences of three Akebia species, laying a foundation for further development and utilization. This type of study can lead to the identification of a compound that, with further work and more extensive studies, has the potential to be used as a biomarker, in this case to distinguish different medicinal species. [ABSTRACT FROM AUTHOR]

• A risk evolution analysis model is newly developed to investigate the ship collision risk in pilotage process, which attracts little attention in the existing literature. • A Functional Resonance Analysis Method (FRAM) and Dynamic Bayesian Network (DBN) are combined to investigate process risk of high dynamic and uncertain features. • Various objective (AIS) and subjective datasets are used to quantify the DBN network based on hybrid uncertainty methods. • The temporal risk inference is conducted to reveal the risk evolution law in ship pilotage operations process. The risks involved in ship pilotage operations are characterized by random, uncertain and complex features. To reveal the spatiotemporal evolution of ship collision risks in the pilotage operations process, a risk evolution analysis model is developed in this paper by the combination of a Functional Resonance Analysis Method (FRAM) and Dynamic Bayesian Network (DBN). First, based on the analysis results of the functional resonance mechanism of a ship pilotage system, the relevant collision risk influencing factors (RIFs) and their coupling relationships are identified. Second, the DBN is quantified by the employment of various uncertainty treatment methods including the Dempster-Shafer evidence theory for the configuration of the prior probabilities and a Markov model for the dynamic factors' transition probability calculation. Finally, using the temporal observation data, the temporal risk inference is conducted to reveal the risk evolution law in a ship pilotage operations process. The findings show that the evolution of collision risk in ship pilotage is significantly sensitive to regional locations, resulting in a "U" curve shaped by the action of functional resonance. "Inadequate human look-out" is among the most influential factors, and hence targeted risk control strategies should be formulated to ensure the safety of ship pilotage operations. [ABSTRACT FROM AUTHOR]

Polymer field-effect transistors (PFETs) are promising candidates for future electronics due to easy and inexpensive fabrication. Poly{[ N , N ′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene) [P(NDI2OD-T2)] based PFET devices with poly (methyl 2-methylpropenoate) (PMMA) as dielectric were fabricated successfully and it was found that the charge transporting behaviors were greatly impacted by the molecular weight of PMMA. Both hole and electron mobilities were improved simultaneously with increasing molecular weight of PMMA. In addition, similar result was also obtained in the PFETs based on a semiconductor, poly{[ N , N ′-bis(2-octyldodecyl)-1,4,5,8-naphthalenediimide-2,6-diyl-alt-5,5′-di(thiophen-2-yl)-2,2′-(E)-2-(2-(thiophen-2-yl)vinyl)thiophene]}. Furthermore, the corresponding complementary-like inverters with PMMA displayed a gain value of 100. We studied the interface between the semiconducting and dielectric layers and found that the low trap density with higher-molecular-weight PMMA attributes to high mobilities of electrons and holes. This work provides a new way to fabricate high-performance PFETs and to improve performance of the complementary circuits through studying the effects of polymeric gate dielectrics, compared to the conventional view of semiconducting materials. [ABSTRACT FROM AUTHOR]

• Summary and comparison of ballast standards in different countries. • Promising future ballast technologies are discussed. • Ballast qualification considering different material types and local geologies. The properties of railway ballast material are affected by the local geologies and climatic environments from which the parent rock is sourced. These factors can make it challenging to select the most appropriate material for railway applications. To address this issue, this paper first reviews the means of ballast selection in complex environments across the world. The selection criteria for ballast materials are compared and test methods for ballast quality quantification are summarised. Next, ballast parent rock types and the implications of mining approaches are discussed, before analysing ballast morphology with respect to ballast size and shape. Then ballast petrography is reviewed with a focus on the effect of mineral composition on performance. Finally, some promising future ballast technologies are discussed with a focus on environmental performance. These include recycled ballast, asphaltic materials, steel slag and ballast gluing. The review shows that regarding ballast selection means and criteria, the number and type of quantitative indicators varies greatly between countries. In particular there are divergences in test methods and quantitative indicators for ballast quality considering material types and local geologies. Suggested future research directions are proposed, such as the effect of tamping and dynamic track stabilisation on ballast properties. [ABSTRACT FROM AUTHOR]

• Six diverse railway lines were inspected by the GPR, proving the GPR application feasibility for diverse railway line conditions. • Accuracy of the GPR-based fouling index is correlated with sieving-based fouling index. • By comparing the sensitivity of different indicators, the suitable GPR signal processing means is obtained. • Fouling composition is proved as a decisive factor for GPR-based fouling level evaluation, especially the iron ore. Ballast layer condition should be more regularly and accurately inspected to ensure safe train operation; however, traditional inspection methods cannot sufficiently fulfil this task. This paper presents a method of ground penetrating radar (GPR) application to reflect ballast layer fouling levels under diverse field conditions (annual gross passing load, cleaning and renewal year, fouling composition and transportation type). The results show that the GPR-based inspection method can assess the ballast layer fouling level with a 1–7% difference from the traditional sieving results. Fouling composition (especially metal materials) has a great effect on the GPR signals, thus affecting the inspection accuracy of ballast layer fouling level. Developing diverse GPR-based fouling indicators (by distinguishing different GPR signal features) can improve the GPR inspection applicability to the diverse field conditions. [ABSTRACT FROM AUTHOR]

• Coupled DEM-FDM-MBD model to study train-track-subgrade dynamic responses. • Crumb rubber (or tire-derived aggregates) effects on train-track-subgrade dynamic responses. • Crumb rubber size effects on the train-track-subgrade dynamic responses presented by ballast friction energy dissipation. Crumb rubber (CR) has been proposed to apply in the ballast or sub-ballast layer for ballast degradation mitigation and vibration (noise) reduction. The CR can change the ballast layer stiffness, which can affect the train-track-subgrade dynamic performance and cause travel comfort and safety issues. Towards this, this study aims at confirming 1) how much the CR application can affect the dynamic performance of train and ballast layer; 2) to what extent the CR-ballast layer can distribute the train loadings to reduce subgrade surface stress. To achieve this aim, a whole train-track-subgrade system model was built by coupling multibody dynamics (MD), discrete element method (DEM) and finite difference method (FDM). The MD was used to build the train, including one vehicle body, two bogies and four wheelsets. The DEM was used to build the ballasted track, including rail, sleepers and ballast layer. The FDM was used to build the subgrade. Using the coupled model, the dynamic performance of train and track were studied, including the vehicle body acceleration, wheel-rail force, rail dynamical bending moment, sleeper acceleration, sleeper displacement and ballast acceleration. In addition, the energy dissipation of the ballast bed was also presented. For the subgrade, the subgrade surface acceleration and surface stress were measured and analysed. In the model, different CR size and percentage were considered. Results show that using the CR in ballast layer can increase the accelerations of sleeper, rail and train. But it can decrease the ballast degradation, subgrade surface acceleration and subgrade surface stress. CR helps consume train loading energy, reducing the energy that has to be consumed by ballast friction. Small size CR (8–22.4 mm) has greater influence on dynamic performance of the whole train-track-subgrade system than big size CR (9.5–63 mm). In summary, 10% percentage of CR-ballast mixture is recommended, and for CR size it is difficult to give a recommendation. Small size CR increase ballast acceleration more than big size CR, but small size CR are better at improving sleeper displacement, subgrade stress and ballast bed stress. [ABSTRACT FROM AUTHOR]

Abstract: The long-term viscoelastic behavior of polymeric materials used below the glass transition temperature (T g) is greatly affected by physical aging. In contrast to isothermal physical aging, long-term response under nonisothermal history has received far less attention. This paper reports experimental results and analytical methods of long-term creep behavior of polyphenylene sulfide (PPS) subjected to complex thermal histories in a temperature range below T g. To characterize the effects of aging, creep tests were performed using a dynamic mechanical analyzer (DMA). Besides the long-term data, short-term creep tests in identical thermal conditions were also analyzed; these were utilized with effective time theory to predict long-term response under both isothermal and nonisothermal temperature histories. The long-term compliance after a series of temperature changes was predicted by the effective time theory using the KAHR-a te model to obtain nonisothermal physical aging shift factors. Comparison of theoretical predictions with experimental data shows good agreement for various thermal histories. [Copyright &y& Elsevier]

• Overview of tamping to ballasted track. • Included plenty of the published studies on tamping to ballast layer. • Presented cutting-edge techniques or methods for ballasted track maintenance. • Explained state-of-art methods for ballasted track inspection. Railway ballast beds bear cyclic loadings from vehicles and deteriorate due to ballast particle degradation (breakage and abrasion), ballast pockets (subgrade defects), fouling (or contamination) and plastic deformation of the beds. Ballast bed deterioration changes the ballast track geometry, which leads to uncomfortable rides, exacerbates wheel-rail interactions and, most importantly, causes safety issues (e.g., derailment). To align the track geometry, tamping is the most widely used means of filling ballast-sleeper gaps and homogenizing ballast beds. Although many studies have been performed on tamping, some necessary research gaps still need to be addressed. To stress the research gaps, tamping studies are critically reviewed in this paper, and the tamping mechanisms, challenges and proposed solutions are introduced and discussed. This review aims to 1) help researchers discover important research directions related to tamping, 2) propose means for tamping methodology improvement/development, and 3) provide advice for developing novel railway track maintenance. [ABSTRACT FROM AUTHOR]

• Particle Image Velocimetry (PIV) was applied for DEM model calibration on mesoscopic level. • Ballast rheology (movements) of one ballast bed cross section is presented and analysed. • Lateral resistance of ballast bed to sleeper is studied from the perspective of ballast rheology. Ballast rheology is a phenomenon that describes movements of ballast particles due to the discrete nature, which eventually leads to the ballast bed fluid deformation after a long-time service. In most cases, ballast rheology is the main reason of track irregularity that leads to some track defects, e.g., hanging sleeper and mud spots. Therefore, it is significant to confirm the ballast rheology mechanism, which not only benefits for alleviating track defects, prolonging track service and providing safe transportation, but also provides an innovated means for accurately calibrating the discrete element method (DEM) models. Towards this aim, the Particle Image Velocimetry (PIV) is utilised to study ballast rheology through measuring ballast particle displacements in the single sleeper push test (SSPT). The ballast rheology results are compared with those from the DEM SSPT model, through which the DEM model is calibrated. Results show that the PIV is an effective technical means for ballast rheology study and DEM model calibration. This study is helpful for the researchers to build more precise DEM models, further providing theoretical methodology for ballast track construction and innovations. [ABSTRACT FROM AUTHOR]

• Innovated sleeper shape with texture attached at sleeper bottom. • Comparison of different friction sleeper design. • Discrete element modelling of sleeper-ballast interaction. • A rapid method for discrete element method model construction. The lateral stability of ballasted track becomes more important because of the safety requirement under the demand of higher train speed and heavier axle load. To increase the lateral resistance of ballast bed, this paper proposes three types of new sleepers, frictional sleepers. The frictional sleepers are sleepers with different shapes of textures attached at the sleeper bottom. To study the application feasibility of the frictional sleepers, experimental tests (single sleeper pull-out test) and numerical simulation (discrete element modelling) are performed. The lateral resistances of the three types of frictional sleepers are compared with the traditional sleeper based on the experimental test, and the mechanism of the lateral resistance increase is revealed according to the numerical simulation. The results indicate that the frictional sleepers can increase the lateral resistance by 32% (maximum), due to the enhanced interaction between sleeper and ballast particles. More importantly, different types of frictional sleepers have different performances, and the optimal friction sleeper is confirmed. This study is helpful for the further research on sleeper design. [ABSTRACT FROM AUTHOR]

• Propose a unidirectional heat transfer solar still (UHTSS) with multistage condensation structure. • Analyze the heat transfer advantages of UHTSS and optimize the parameters of the solar still based on this. • The evaporation rate can reach 6.0 kg·m−2·h−1 under sunlight, and the collection rate of fresh water can reach 4.5 kg·m−2·h−1. Solar-driven interfacial evaporation technology exhibits notable performance in evaporation, with evaporation efficiency typically maintained at over 80 %. However, utilizing interfacial evaporation for efficient seawater desalination remains a challenge due to low production of freshwater. Therefore, we propose a desalination system based on unidirectional heat transfer solar still, which is capable of combining efficient evaporation with waste heat recovery to achieve high energy utilization. The design of the solar still decomposes the light transmission and condensation functions of the glass cover plate in traditional solar still for independent optimization and reserves space for integrating high-performance interfacial evaporation materials, while minimizing heat loss by ensuring unidirectional heat transfer inside the still. In particular, the proposed unidirectional heat transfer solar still provides a free interface to condense the vapor, where a multi-stage condensation is integrated to recycle latent heat. When using a self-made hydrogel sponge as the interfacial evaporation material, the solar still achieve efficient and stable freshwater production. Outdoor experiments showcase a evaporation rate of 6.0 kg·m−2·h−1, coupled with an freshwater production rate of 4.5 kg·m−2·h−1 under an average sunlight intensity of 1.07 kW·m−2. Our results demonstrate that the freshwater production of the solar still can be further improved. This work is beneficial for further enhancing freshwater collection of solar desalination. [ABSTRACT FROM AUTHOR]

• The performance of recycled and fresh ballast mixture was studied. • The boundary of recycled ballast mixing ratio was found out. • Ballast surface texture was employed in DEM to represent both recycled and fresh ballast. • Recycled ballast could be reinforced by fresh ballast addition. Ballast degradation is frequently observed under cyclic loading, and results in bearing capacity and drainage problem of ballast track. To keep the stability and safety, periodical maintenances are needed, such as cleaning and replacement, which produce a huge amount of wasted ballast. Thus, reusing the deteriorated ballast can become a considerable method for sustainable railway development and environment protection. One applications is adding the cleaned deteriorated ballast (i.e. recycled ballast) into fresh ballast. Furthermore, it is common situation that applying the mixture of fresh and deteriorated ballast during the railway operation. To study the mechanical behaviour of this mixture and find out the criterion weight proportion of the recycled ballast, a series of large direct shear tests were performed with different weight proportions (0%, 10%, 20%, 30%, 40%, and 50%) of recycled ballast mixed into fresh ballast under different normal stresses (50, 100 and 200 kPa). In addition, a numerical simulation based on discrete element method (DEM) was used to illustrate the shear strength, contact forces, coordination numbers and displacements of ballast particles. Results show that the shear strength reduction of the mixture is insignificant, when mixed with less than 30% recycled ballast. With the recycled ballast proportion increasing, the shear strength and coordination number reduce and the displacements get larger. This research provides a foundation for the application of recycled ballast, and on the other hands, adding fresh ballast can be a solution to reinforce deteriorated ballast bed. [ABSTRACT FROM AUTHOR]

Poly(methyl methacrylate) (PMMA)-silica nanocomposite was used to study the adsorption-desorption of polymer chains on the surface of silica nanoparticles. We demonstrate that the adsorption-desorption is a dynamic process with respect to temperature and time. The adsorption condition could be changed after annealing at T g + 16 °C. Then, the physical aging under confinement was investigated under different adsorption conditions. At relatively high aging temperatures, we reveal a one-step equilibration with reduced enthalpy recovery of nanocomposite compared with neat PMMA. In contrast, the aging rate of composite is decelerated and then accelerated after a long period of aging at a relatively low temperature due to the emergence of two-step equilibration. Furthermore, the material system with a higher adsorption fraction exhibits a stronger confinement effect on aging. We speculate that the transition from one-step to two-step equilibration corresponds to the activation of segmental α′ relaxation in the interfacial region. The adsorbed chains result in restrained segmental α′ and β′ relaxation and low enthalpy recovery at relatively high aging temperatures. At a relatively low temperature, the interfacial α′ relaxation with high released enthalpy comes to the surface after a long aging time, inducing the elevated aging rate. [Display omitted] • The effect of heat treatment on adsorption-desorption was examined. • A change from one-step to two-step equilibration was found in PMMA/silica nanocomposites with decreasing aging temperatures. • The underlying mechanism was revealed by broadband dielectric relaxation. [ABSTRACT FROM AUTHOR]

An effective assay method for monitoring protein kinase activity and screening inhibitors is greatly beneficial to kinase-related drug discovery, early diagnosis of diseases, and therapeutic effect evaluation. Herein, we develop a simple electrochemical method for detecting the activity of casein kinase II (CK2) based on phosphorylation against carboxypeptidase Y (CPY) digestion triggered signal amplification, where CK2 catalyzed phosphorylation event protects the substrate peptide from the digestion of CPY, maintains the repulsive force of the substrate peptide towards the redox probe, and results in a weak electrochemical signal. Whereas, without phosphorylation, the substrate peptide is digested by CPY and a strong electrochemical signal is obtained. The detection feasibility is demonstrated for the assay of CK2 activity with low detection limit of 0.047 unit/mL. Moreover, the biosensor was used for the analysis of kinase inhibition. Based on the electrochemical signal dependent inhibitor concentration, the IC 50 value of ellagic acid was estimated to be 39.77 nM. The proposed method is also successfully applied to analyze CK2 activity in cell lysates, proving the applicability in complex biological samples. [ABSTRACT FROM AUTHOR]

• The influence of several modifiers on bitumen is testified. • The relationship between components and performance of bitumen is revealed. • A model of bitumen microstructure changing with components is proposed. In order to investigate the impact of bitumen components on its overall properties, various modified bitumen with 1.0 %PPA or 2.0 %SBS/SBR + 0.6 %PPA were prepared. The influence of PPA dosage on bitumen's physical properties were evaluated, and the macroscopic and microscopic properties of each bitumen sample were characterized by DSR, BBR and atomic force microscopy observation. The components of bitumen were separated through SARA test, and the infrared spectroscopy of asphaltenes was further analyzed. The findings suggest a significant impact on bitumen with PPA incorporation, the elastic recovery properties of bitumen at high temperatures were enhanced due to a more stable colloidal structure was formed by the dispersion and interaction of macromolecular asphaltenes. However, the low-temperature rheological properties of bitumen were impaired by reason of a relatively reduced flowable lightweight component. Specifically, the large asphaltenes clusters were dispersed cause PPA reacted with the –OH bonds of alcohols in bitumen by phosphorylation. By modeling the correlation between bitumen component contents and its microscopic surface parameters, the asphaltenes decomposition was demonstrated to be an important factor on the microscopic morphology, which was also related to the content of saturates and aromatics. Thus, a method for deconstructing bitumen from a compositional perspective is proposed. [ABSTRACT FROM AUTHOR]

The dynamic response of a railway bridge can be affected by the properties of its foundations, particularly if founded on soft soils. Thus, this work aims to establish a coupled dynamic model to investigate the vibration of train-track-bridge systems considering piled foundations embedded in soft soil. Firstly, to construct the simulation framework, the finite element and multi-body methods are used to model the dynamic behavior of a train-track-bridge interaction (TTBI) system and a pier-cap-pile-soil interaction system. The equilibrium of the two sub-systems is maintained through the bridge's bearing force and a multi-time-step integration strategy is introduced to improve computational efficiency. The proposed model is validated by comparing it to the results from commercial finite element software ABAQUS. Then results are computed using the proposed model and the conventional TTBI model without piles. It is concluded that when considering the piled foundations, the low-frequency vibration of the TTBI system is dominant. Moreover, the vibration energy in the track and bridge below 7 Hz is larger compared with the conventional TTBI model. The influence of train speed on the vibration characteristics of the pile and soil is analyzed. It is found that higher train speeds cause increased pile and soil accelerations at the frequencies associated with the train axle spacing. The novelty of the analysis is providing a new insight into the coupled vibration properties of TTBI systems considering the participation of piled foundations in soft soil. • A dynamic model is established to investigate the coupled vibration of train-bridge interaction considering piled foundation in soft soil. • The vibration transmission of train-bridge-pile-soil interaction is analyzed and quantified. • The power flow is used to depict the train-induced vibration level of structures subjected to the piles embedded in soft soil. [ABSTRACT FROM AUTHOR]

Abstract: A novel dicyanovinyl-functionalized N,N,N’,N’-tetraphenylbenzidine (TPD) derivative, N,N’-bis[4-(1,1-dicyanovinyl)phenyl]-N,N’-bis(4-fluorophenyl)benzidine and a novel triphenylamine-based derivative, 4,4′,4″-tris{[di(p-tolyl)amino]phenyl}triphenylamine were synthesized and employed as red molecular emitter and hole-transporting layer, respectively, in an undoped organic light-emitting diode devices. The device based on the TPD-FCN emitter and DBTPA hole-transporting material, which was fabricated in a facile non-doped configuration, achieved maximum luminance of 3400 cd m−2 at a driven voltage of 17.5 V and maximum luminous efficiency of 3.04 cd A−1. Interestingly, the device reached a brightness of 1399 cd m−2 and luminous efficiency of 2.85 cd A−1 at the low current density of 20 mA cm−2. [Copyright &y& Elsevier]