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Objective To better interpret the geological information contained in geophysical logging data and expand the application scope of well logs in geology, Methods several typical cases of representative logging data are analyzed. This analysis seeks to enhance the use of well logs in geological research. Logging data can aid in the deployment of sidetracking wells by identifying tectonic occurrences and variations in their combination characteristics. Image log data also enable determintion of palaeocurrent directions and the identification of bidirectional provenance supply, thus providing refined and scientifically calibrated interpretations in alignment with geological understanding. Results Logging data, often regarded as the "eyes" of geologists, are advantageous for identifying and evaluating pores, caves, fractures, and other subsurface features. These data are crucial for discovering hydrocarbon reservoirs and facilitating the fine and continuous calculation of reserve parameters. The coupling relationships between mudstone resistivity, acoustic interval transit time, and in situ stress in logging curves can also be used to indirectly predict the quality of ultradeep reservoirs and hydrocarbon productivity. Moreover, combining geology, logging, and seismic activity allows for the delineation of hydrocarbon traps and supports oil and gas exploration and production. Conclusion The analysis of these typical cases assists geologists in better interpreting the geological information in logging curves and further broadens the application field and scope of geophysical logging data.

Ensuring railway safety is a top priority, with a central focus on preventing accidents. By thoroughly analyzing data from railway accident investigations, we can pinpoint factors and patterns associated with different types of railway accidents. This proactive approach not only helps reduce the frequency of such incidents but also significantly boosts overall railway transportation safety. This paper investigates the impact of various risk factors on railway safety through the analysis of railway accidents by using data-driven Bayesian networks. First, key data representing the frequency of risk factors directly derived from railway accident reports are collected and analyzed. Then, the risk factors are incorporated into causal analysis for different types of railway accidents. Finally, a historical data-driven approach is utilized to model and gain new insights into the key risk factors causing different types of railway accidents. Meanwhile, a Tree-Augmented Naive Bayes (TAN) is employed to construct a model of interdependencies among risk factors, and the model is validated through sensitivity analysis and past accident records. The research findings demonstrate that the crucial risk factors for all types of accidents include undetected track damage, train operator skills, load, braking system conditions, train speed, traction system failures, level crossings, and bridge damage. Additionally, the research results highlight the differential impact of key factors on different types of accidents, providing a most probable explanation for observing the most likely configurations in the model for a specific scenario. This work contributes to accident prevention and safety decision-making.

The dynamic surveillance and monitoring of sea area and islands is an effective means to enhance the management of sea areas. This paper studies and sorts out the sea area and island surveillance and monitoring system, analyzes the advantages of UAV low-altitude remote sensing technology in surveillance and monitoring work, designs and establishes UAV surveillance and monitoring business management system, which is applied to island surveillance and monitoring in Nansha District, and introduces several practical applications. The method of using UAV low-altitude remote sensing technology as the main method and establishing UAV surveillance and monitoring platform has expanded and enriched the results of surveillance and monitoring, and effectively promoted the improvement of the supervision capacity of sea area and islands.

Filler agglomeration, single filler type, poor filler-matrix compatibility, and lack of toughness are the main problems that restrict the development of the polyvinyl chloride (PVC) manufacturing industry. In this work, PVC composites were prepared with silica micropowder (SMP) as a filler. Titanate coupling agent (TCA-KTTO) modification and chlorinated polyethylene (CPE) toughening treatment were utilized to enhance the composites performance. Herein, we successfully obtained SMP/PVC composites with high strength, high toughness, and outstanding heat resistance. The optimal dosage of titanate coupling agent for SMP surface modification was determined to be 1.5 wt% by mechanical and thermal conductivity tests. With an increase in the filling content of modified silica micropowder (mSMP), the density, surface hardness, Young's modulus, flexural modulus, thermal conductivity, and thermal stability of mSMP/PVC composites were significantly improved. The notched impact strength of mSMP/PVC composites shows a significant increase with the addition of CPE. At a CPE dosage of 7.5 parts per hundred parts of resin (phr), the notched impact strength of mSMP/PVC composites was enhanced by 59.15%, and the glass transition temperature was improved by 6.1 °C. The co-extruded hollow flooring, fabricated by the SMP reinforced PVC composites, meets Chinese standard GB/T 24508-2020, which has a wide range of applications in panels and profiles, such as seaside boardwalks and outdoor parks.

China’s rail transit system is developing rapidly, but achieving seamless high-precision localization of trains throughout the entire route in closed environments such as tunnels and culverts still faces significant challenges. Traditional localization technologies cannot meet current demands, and the present paper proposes an autonomous localization method for trains based on pulse observation in a tunnel environment. First, the Letts criterion is used to eliminate abnormal gyro data, the CEEMDAN method is employed for signal decomposition, and the decomposed signals are classified using the continuous mean square error and norm method. Noise reduction is performed using forward linear filtering and dynamic threshold filtering, respectively, maximizing the retention of its effective signal components. A SINS/OD integrated localization model is established, and an observation equation is constructed based on velocity matching, resulting in an 18-dimensional complex state space model. Finally, the EM algorithm is used to address Non-Line-Of-Sight and multipath effect errors. The optimized model is then applied in the Kalman filter to better adapt to the system’s observation conditions. By dynamically adjusting the noise covariance, the localization system can continue to maintain continuous high-precision position information output in a tunnel environment.

The galloping of the catenary positive feeder and sand deposition along the railway are very serious of LanzhouUrumqi high-speed railway in the gale areas. In this paper, the second wind-break wall was set up at different positions of the windward side embankment, and the flow field model of the computational domain was established based on the theory of hydrodynamics. The aerodynamic characteristics of the positive feeder and the change of sand deposition along the railway under the condition of double wind-break walls were analyzed. The results show that the range of wind speed growth area at the positive feeder is significantly reduced after the second wind-break wall was set up under the embankment, and the change of the height and position of the wind-break wall has an important influence on the aerodynamic characteristics of the positive feeder. When the second wind-break wall was 0.5 m away from the embankment, the aerodynamic coefficient of the positive feeder is relatively low. At the same time, with the increase of the height of the wind-break wall, the lift and drag coefficient of the positive feeder does not show a continuous decreasing trend. Therefore, on the basis of considering the economic cost and through comparative analysis, the second wind-break wall was designed to be 0.5 m away from the embankment and 1 m height. It can not only restrain the galloping of the positive feeder to a certain extent, but also effectively alleviate the hazards of sand deposition on the railway, thus greatly improving the stability of train operation safety in gale areas.

Aiming at the failure of the combination of highly conflicting evidence, the combination of the relationship between evidences and the characteristics of evidence itself was considered, and a method of conflicting evidence combination based on clustering weighting was proposed.Firstly, the similarity coefficient was constructed to cluster the evidence, and the inter-class weight was determined by class capacity to reflect the differences among classes.Then the information entropy was used to obtain the intra-class weight of each evidence.The modified weight of the evidence was obtained by combining the inter-class weight and intra-class weight.Finally, the conflict evidence was modified according to the weight, and the combination rule of evidence theory was used to achieve the final synthesis of the modified evidence.The results of the example show that the proposed method can reasonably carry out evidence correction, and the combined results have better focusing effect than other methods.

To study the electrical characteristics of ice-covered insulators, this paper uses the finite element method to simulate the BXN-25 type insulator of the positive feeder of the catenary under three icing conditions of different icing thickness, icicle length, air gap position, and compares it with the clean insulator. The research shows that icing on the surface of the insulator shed will reduce the insulation distance, thus affecting the insulation performance of the insulator. The electric field distributions are also different with the different number of icicle bridge insulator sheds. When the icicle bridge is connected to different positions of the insulator shed, the air gaps at different positions will be generated. The amplitude of the air gap will increase sharply when it is located at the low-voltage end, making the insulator more prone to flashover.

Railway signals’ fault text data contain a substantial amount of expert maintenance experience. Extracting valuable information from these fault text data can enhance the efficiency of fault diagnosis for signal equipment, thereby contributing to the advancement of intelligent railway operations and maintenance technology. Considering that the characteristics of different signal equipment in actual operation can easily lead to a lack of fault data, a fault diagnosis method for railway signal equipment based on data augmentation and an improved attention mechanism (DEIAM) is proposed in this paper. Firstly, the original fault dataset is preprocessed based on data augmentation technology and retained noun and verb operations. Then, the neural network is constructed by integrating a bidirectional long short-term memory (BiLSTM) model with an attention mechanism and a convolutional neural network (CNN) model enhanced with a channel attention mechanism. The DEIAM method can more effectively capture the important text features and sequence features in fault text data, thereby facilitating the diagnosis and classification of such data. Consequently, it enhances onsite fault maintenance experience by providing more precise insights. An empirical study was conducted on a 10-year fault dataset of signal equipment produced by a railway bureau. The experimental results demonstrate that in comparison with the benchmark model, the DEIAM model exhibits enhanced performance in terms of accuracy, precision, recall, and F1.

Regenerative braking energy (RBE) will be generated when high-speed train is in braking state, but the utilization rate of RBE is generally low. To solve this problem, based on the hybrid energy storage system (HESS), a scheme for energy storing and utilizing high-speed train RBE is proposed. In this scheme, the HESS is connected to the railway traction power supply system through the railway power conditioner (RPC) as the interface circuit. The control strategy of energy storage RPC is proposed by analyzing the compensation principle, then the power of two energy storage media is allocated. The effectiveness of the scheme is verified by simulation. The findings of the research suggest that the control strategy of energy storage RPC can not only effectively utilize RBE generated by high-speed train, but also improve the power quality and extend the service life of energy storage system.

Zymomonas mobilis is a promising microorganism for industrial bioethanol production. However, ethanol produced during fermentation is toxic to Z. mobilis and affects its growth and bioethanol production. Although several reports demonstrated that the RNA-binding protein Hfq in Z. mobilis contributes to the tolerance against multiple lignocellulosic hydrolysate inhibitors, the role of Hfq on ethanol tolerance has not been investigated. In this study, hfq in Z. mobilis was either deleted or overexpressed and their effects on cell growth and ethanol tolerance were examined. Our results demonstrated that hfq overexpression improved ethanol tolerance of Z. mobilis, which is probably due to energy saving by downregulating flagellar biosynthesis and heat stress response proteins, as well as reducing the reactive oxygen species induced by ethanol stress via upregulating the sulfate assimilation and cysteine biosynthesis. To explore proteins potentially interacted with Hfq, the TEV protease mediated Yeast Endoplasmic Reticulum Sequestration Screening system (YESS) was established in Z. mobilis. YESS results suggested that Hfq may modulate the cytoplasmic heat shock response by interacting with the heat shock proteins DnaK and DnaJ to deal with the ethanol inhibition. This study thus not only revealed the underlying mechanism of enhanced ethanol tolerance by hfq overexpression, but also provided an alternative approach to investigate protein-protein interactions in Z. mobilis.

To investigate the mechanical characteristics of catenary positive feeders under galloping state in gale areas, the aluminium cable steel reinforced (ACSR) LGJ-300/25 used in the catenary positive feeder of the LanzhouUrumqi high-speed railway is taken as an example. Then, on the basis of galloping amplitude and frequency, the tension on the conductor is deduced. In accordance with the structural and material characteristics of the conductor, a 3D finite element model of the positive feeder is constructed by ABAQUS software. The correctness of the model is verified by comparing the theoretical calculation and simulation results of tension stratification. Different tensile loads are applied to the model to simulate the force of the positive feeder under different galloping degrees, and the mechanical changes of the whole and sections of the steel and aluminium strands are analysed. Results show that under tensile load, the overall deformation of the positive feeder presents a stepped distribution, and the tension of the steel core and aluminium strand varies from inside to outside; the tension ratio is approximately 3:2. The stress at the outlet of the suspension clamp is complex and prone to stress concentration, which mainly causes the fatigue damage of the positive feeder. The results of this study can provide a theoretical reference for the selection and optimal design of electrified railway conductors in gale areas.

Focusing on the issues of the effects of the high failure rate and poor maintenance on the ZPW-2000A track circuit during in-field operations, this paper proposes a multi-objective maintenance decision optimization method by considering the number of maintenance personnel. The developed method introduces not only the service age regression, increased failure rate, system's average reliability, maintenance costs, but also the availability calculation model in the case of multiple maintenance personnel. We solve the model using the integer coded BB-MOPSO algorithm, and obtain the Pareto front solution set, and then the optimal maintenance plan of the system is further established. In addition, the number of optimal maintenance personnel is analyzed in detail. Compared to the results of traditional maintenance strategies, the results obtained in this paper show that the proposed model can reduce the maintenance costs, under the same working conditions, by 13.29%, moreover, it can more comprehensively reflect the impact of maintenance activities on the system reliability, maintenance costs, and availability. Furthermore, the method can meet the needs of decision-makers for diversified solutions and can provide an effective decision support while on site.

Degradation modeling using heterogeneous degradation data of a system population is critical for prognostics and health management. The heterogeneity may result from the inherent differences in the degrading systems and measuring instruments, as well as from the extrinsic environmental differences, making it difficult to predict the failure. Current studies have not considered the multiple sources of heterogeneity simultaneously, and consequently, have failed to capture the actual degradation process. To explain and quantify the combined effect of multi-source heterogeneity, we present a random effects Wiener process model with heteroscedastic measurement errors, where the parameters of the drift, diffusion, and error variance are assumed as random variables following a certain distribution. The Markov chain Monte Carlo method is adopted to estimate the posterior distributions of the actual degradation states and the model parameters under a hierarchical Bayesian framework. Based on the concept of first hitting time, the failure time distribution is estimated. To verify the presented approach, comparative studies are conducted with simulation and laser degradation data. The results show that considering multi-source heterogeneity can further eliminate the inter-individual variation in degradation data and improve the model fitting and prediction accuracy.

To prevent the catenary positive feeder of Lanzhou–Urumqi High-speed Railway from violent galloping under strong wind, The aerodynamic characteristics of different phases of composite cross-sections formed after an air flow spoiler was installed on the catenary positive feeder is calculated by finite element method, and the effectiveness of the airflow spoiler in restraining the galloping of catenary positive feeder in the strong wind areas of the Lanzhou–Urumqi High-speed Railway was studied. The anti-galloping effect of three typical diameter air flow spoilers are compared. Results showed that the number and size of vortices generated in the wake area of different composite body sections varied after the air flow spoiler was installed. The aerodynamic coefficients after air flow spoiler installation were lower than those before installation. All the spoilers exhibited a good anti-galloping effect, with the best effect exhibited by 0.75 D spoiler. Again, the research results can provide theoretical support for further refinement of the mechanism of the air flow spoiler to suppress the galloping of non-icing conductors.

Graphene is a two-dimensional nanomaterial with excellent mechanical, electrical and thermal properties. The application of graphene in cement-based materials has good prospects. However, the mechanical properties of cement-based materials are difficult to be significantly enhanced by ordinary graphene nanoplates. In this paper, nitrogen-doped graphene is first reported as an additive with dosages of 0.01, 0.02, 0.03, 0.04 and 0.05 wt.%, respectively, to prepare iron ore tailings–based cementitious composites. The iron ore tailings–based cementitious composite with 0.02 wt.% graphene shows an extremely high flexural strength of 15.05 MPa at 3 days, which is 134.4% higher than that of the iron ore tailings–based cementitious composite without graphene. The effects of graphene content and curing age on the flexural strength and microstructure of iron ore tailings–based cementitious composites were studied. In particular, the scanning electron microscope was adopted to observe the micromorphology of the composites. It is helpful to understand the graphene reinforcement mechanism for the high early flexural strength of iron ore tailings–based cementitious composites. By altering the morphology of iron ore tailings–based cementitious composites, graphene plays two roles in the composites. One role is to connect C-(A)-S-H gels, ettringite and other hydrated crystals to construct a three-dimensional structure. The other is to attract iron ore tailings distributed on its platform to enhance its flexural strength properties. These findings provide favorable guidance for the performance enhancement and mechanism replenishment of graphene-reinforced cementitious composites.

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a global crisis; however, our current understanding of the host immune response to SARS-CoV-2 infection remains limited. Herein, we performed RNA sequencing using peripheral blood from acute and convalescent patients and interrogated the dynamic changes of adaptive immune response to SARS-CoV-2 infection over time. Our results revealed numerous alterations in these cohorts in terms of gene expression profiles and the features of immune repertoire. Moreover, a machine learning method was developed and resulted in the identification of five independent biomarkers and a collection of biomarkers that could accurately differentiate and predict the development of COVID-19. Interestingly, the increased expression of one of these biomarkers, UCHL1, a molecule related to nervous system damage, was associated with the clustering of severe symptoms. Importantly, analyses on immune repertoire metrics revealed the distinct kinetics of T-cell and B-cell responses to SARS-CoV-2 infection, with B-cell response plateaued in the acute phase and declined thereafter, whereas T-cell response can be maintained for up to 6 months post-infection onset and T-cell clonality was positively correlated with the serum level of anti-SARS-CoV-2 IgG. Together, the significantly altered genes or biomarkers, as well as the abnormally high levels of B-cell response in acute infection, may contribute to the pathogenesis of COVID-19 through mediating inflammation and immune responses, whereas prolonged T-cell response in the convalescents might help these patients in preventing reinfection. Thus, our findings could provide insight into the underlying molecular mechanism of host immune response to COVID-19 and facilitate the development of novel therapeutic strategies and effective vaccines.

In this paper, we investigated the possibility of applying the low power pulse laser welding technology to surface a protective layer against heavy liquid metal corrosion in fuel cladding tube made of austenitic 316L stainless steel. Based on results from flaring, flattening, bending tests and metallographic microscope investigations, we can preliminarily confirm the possibility of using low power pulse laser with specific power input to weld Fe-10Cr-4Al-RE alloy on the outer surface of a 316L stainless steel tube with the inner diameter of 11.8 mm and wall thickness of 0.65 mm.

Water huff and puff in horizontal wells in tight reservoirs has achieved good results in replenishing formation energy. However, after multiple rounds of treatment, a rapid decrease in formation pressure takes place making it difficult to maintain stable production. To improve the oil recovery rate of tight reservoirs, it is imminent to change the development mode. In this work, the stress distribution characteristics at fracture tips were analyzed based on Irwin theory and elastic theory. A model of propagation and closure length of fractures was established based on the propagation mechanism of water injection-induced natural fracture and the energy balance principle of fracture mechanics. Surfactant imbibition experiments were carried out according to the imbibition principle of surfactant system, and the propagation law of natural fractures was described with numerical simulation to analyze the seepage characteristics of dynamic fracture network. On the basis of the above works, alternating water huff and puff into segmented injection and production was proposed according to the distribution law of dynamic fracture network. The developing process of an actual well case by these two developing modes was simulated to predict 18 years of cumulative recovery, pressure distribution, and recovery rate. Results showed that when stress intensity factor exceeds the fracture toughness, the natural fractures will extend along their original directions and get connected, forming an irregular fracture network. The lengths of fractures after propagation and closure will not bring about water channeling for they are far shorter than well and interval spacing. Surfactant could diminish the resistance of boundary layer by reducing the wetting contact angle, ending up with an improvement in imbibition efficiency. Radial displacement and dynamic imbibition occur simultaneously in a dynamic fracture network during the early stage of water injection, while static imbibition mainly occurs during injection shutdown period and well soaking. According to comparison, the swept area of segmented injection and production was larger, ending up with a continuous increase of simulated recovery rate and cumulative recovery. The findings of this study show alternating water huff and puff after to segmented injection and production in fractured tight reservoir can allow full play of dynamic fracture network’s potential and achieve effective enhancement in oil recovery rate.

The Lanzhou-Xinjiang (Lan-Xin) high-speed railway is one of the principal sections of the railway network in western China, and signal equipment is of great importance in ensuring the safe and efficient operation of the high-speed railway. Over a long period, in the railway operation and maintenance process, the railway signaling and communications department has recorded a large amount of unstructured text information about equipment faults in the form of natural language. However, due to irregularities in the recording methods of these data, it is difficult to use directly. In this paper, a method based on natural language processing (NLP) was adopted to analyze and classify this information. First, the Latent Dirichlet Allocation (LDA) topic model was used to extract the semantic features of the text, which were then expressed in the corresponding topic feature space. Next, the Support Vector Machine (SVM) algorithm was used to construct a signal equipment fault diagnostic model that reduced the impact of sample data imbalance on the classification accuracy. This was compared and analyzed with the traditional Naive Bayes (NB), Logistic Regression (LR), Random Forest (RF), and K-Nearest Neighbor (KNN) algorithms. This study used signal equipment failure text data from the Lan-Xin high-speed railway to conduct experimental analysis and verify the effectiveness of the proposed method. Experiments showed that the accuracy of the SVM classification algorithm could reach 0.84 after being combined with the LDA topic model, which verifies that the natural language processing method can effectively realize the fault diagnosis of signal equipment and has certain guiding significance for the maintenance of field signal equipment.

In this paper, the possibility of applying different welding strategies to overlay an FeCrAl layer against corrosion from heavy liquid metal on a plain plate made of 316L austenitic stainless steel was investigated. This technology could be used in manufacturing the main vessel of CiADS, which may be considered as a more economic and feasible solution than production with the corrosion-resistant FeCrAl alloy directly. The main operational parameters of the laser welding process, including laser power, weld wire feeding speed, diameter of the welding wire, etc., were adjusted correspondingly to the optimized mechanical properties of the welded plate. After performing the standard nuclear-grade bending tests, it can be preliminarily confirmed that the low-power pulse laser with specific operational parameters and an enhanced cooling strategy will be suitable to surface an Fe-10Cr-4Al-RE layer with a thickness of approximately 1 mm on a 40 mm-thick 316L stainless steel plate, thanks to the upgraded mechanical properties incurred by refined grains with a maximum size of around 300 μm in the welded layer.

This paper studies the distributed adaptive cooperative control of multiple urban rail trains with position output constraints and uncertain parameters. Based on an ordered set of trains running on the route, a dynamic multiple trains movement model is constructed to capture the dynamic evolution of the trains in actual operation. Aiming at the position constraints and uncertainties in the system, different distributed adaptive control algorithms are designed for all trains by using the local information about the position, speed and acceleration of the train operation, so that each train can dynamically adjust its speed through communicating with its neighboring trains. This control algorithm for each train is designed to track the desired position and speed curve, and the headway distance between any two neighboring trains is stable within a preset safety range, which guarantee the safety of tracking operation of multiple urban rail trains. Finally, the effectiveness of the designed scheme is verified by numerical examples.

Abstract Varicocele is a common abnormality, but the conventional microsurgical subinguinal varicocelectomy (CMSV) has some disadvantages. We invented Modified Inguinal Microscope-Assisted Varicocelectomy (MIMV) under local anesthesia. This study aims to evaluate MIMV by comparing it to CMSV in operating duration, time to return to normal activity, postoperative complications, achievement of natural pregnancy and improvement of semen quality for patients with infertility, pain score for those with scrotal pain, and so on. We enrolled 3089 patients who underwent MIMV and 476 who underwent CMSV in our hospital. Both the operating duration and the time to return to normal activity of MIMV was shorter than that of CMSV (P

High parking accuracy, comfort and stability, and fast response speed are important indicators to measure the control performance of a fully automatic operation system. In this paper, aiming at the problem of low accuracy of the fully automatic operation control of urban rail trains, a radial basis function neural network position output-constrained robust adaptive control algorithm based on train operation curve tracking is proposed. Firstly, on the basis of the mechanism of motion mechanics, the nonlinear dynamic model of train motion is established. Then, RBFNN is used to adaptively approximate and compensate for the additional resistance and unknown interference of the train model, and the basic resistance parameter adaptive mechanism is introduced to enhance the anti-interference ability and adaptability of the control system. Lastly, on the basis of the RBFNN position output-constrained robust adaptive control technology, the train can track the desired operation curve, thereby achieving the smooth operation between stations and accurate stopping. The simulation results show that the position output-constrained robust adaptive control algorithm based on RBFNN has good robustness and adaptability. In the case of system parameter uncertainty and external disturbance, the control system can ensure high-precision control and improve the ride comfort.

Aiming at the problem of the large tracking error of the desired curve for the automatic train operation (ATO) control strategy, an ATO control algorithm based on RBF neural network adaptive terminal sliding mode fault-tolerant control (ATSM-FTC-RBFNN) is proposed to realize the accurate tracking control of train operation curve. On the one hand, considering the state delay of trains in operation, a nonlinear dynamic model is established based on the mechanism of motion mechanics. Then, the terminal sliding mode control principle is used to design the ATO control algorithm, and the adaptive mechanism is introduced to enhance the adaptability of the system. On the other hand, RBFNN is used to adaptively approximate and compensate the additional resistance disturbance to the model so that ATO control with larger disturbance can be realized with smaller switching gain, and the tracking performance and anti-interference ability of the system can be enhanced. Finally, considering the actuator failure and the control input limitation, the fault-tolerant mechanism is introduced to further enhance the fault-tolerant performance of the system. The simulation results show that the control can compensate and process the nonlinear effects of control input saturation, delay, and actuator faults synchronously under the condition of uncertain parameters, external disturbances of the system model and can achieve a small error tracking the desired curve.

The occurrence of a partial arc can affect insulation properties of the insulator by different types of flashover. In order to investigate the influence of a partial arc on electric field distribution along the catenary insulator string, a three-dimensional model of the cap-pin insulator string with partial arc was established in this paper. The electric field distribution along the insulator string when the arc extended on the insulator surface and bridged sheds was investigated based on the electric field analysis using the finite element method. The results showed that the occurrence of a partial arc caused obvious distortion of the electric field, which was a two-dimensional axis symmetrical field before arcing to a three-dimensional field. In the case of arc extension, the sudden rise of field intensity was mostly at the rib and the shed edge, which had the local maximum field intensity. The rib and the shed edge played a certain hindrance role in the extension of the arc. The main reason for promoting the development of the arc can be attributed to thermal ionization. In the case of arc bridge sheds, the highest field intensity appeared at the edge of the last bridged shed. As the number of sheds arc-bridged increased, the maximum field intensity also increased. As the arc length increased, the electric field intensity of the arc head also increased, which resulted in an accelerated arc development. The main factor to promote the development of the arc can be attributed to electrical breakdown. The measures to hinder the rapid development of partial arcs were proposed.

The global gene regulator Special AT-rich sequence-binding protein-1 (SATB1) has been reported to induce EMT-like changes and be associated with poor clinical outcome in several cancers. This study aims to evaluate whether SATB1 affects the biological behaviors of bladder transitional cell carcinoma (BTCC) and further elucidate if this effect works through an epithelial-mesenchymal transition (EMT) pathway. The expression of SATB1, E-cadherin (epithelial markers), vimentin (mesenchymal markers) in BTCC tissues and adjacent noncancerous tissues, as well as in two cell lines of bladder cancer were investigated. Whether the SATB1 expression is associated with clinicopathological factors or not was statistically analyzed. Cell invasion and migration, cell cycle, cell proliferation and apoptosis were evaluated in SATB1 knockdown and overexpressed cell lines. Our results showed that the expression of SATB1 was remarkably up-regulated both in BTCC tissues and in bladder cancer cell lines with high potential of metastasis. The results were also associated with EMT markers and poor prognosis of BTCC patients. Moreover, SATB1 induced EMT processes through downregulation of E-cadherin, upregulation of E-cadherin repressors (Snail, Slug and vimentin). SATB1 also promoted cell cycle progression, cell proliferation, cell invasion and cell migration, but did not alter cell survival. In conclusion, our results suggest that SATB1 plays a crucial role in the progression of bladder cancer by regulating genes controlling EMT processes. Further, it may be a novel therapeutic target for aggressive bladder cancers.

To effectively suppress the violent galloping of the catenary additional wires in the strong wind section of high-speed railways, the anti-galloping effectiveness and anti-galloping mechanism of the spacer installed on the catenary additional wires are studied. Firstly, the finite element model of the additional wires of the catenary before and after the installation of the spacer is established. Secondly, the random wind field at the additional wires is simulated by the harmonic synthesis method (WAWS). Finally, the galloping response of the additional wires before and after the installation of the spacer is studied by using the finite element software. The results show that the installation of a single spacer at the midpoint of the span can reduce the vertical amplitude of the AF (Additional Feeder) and the PW (Protection Wire) by more than 39.80% and 41.51%, respectively, and the lateral amplitude decreases by more than 16.55% and 38.30%, respectively. The tension of the AF is greatly reduced, while the tension of the PW is slightly increased, so that the galloping of the AF and the PW tends to be synchronized. With the increase in the number of spacers installed, the anti-galloping effect continues to increase. At the same time, the anti-galloping mechanism of the spacer rod to suppress the vibration of the additional wires through the traction effect is clarified, and the effectiveness of the spacer rod in the anti-galloping of the additional wires of the catenary is proved. [ABSTRACT FROM AUTHOR]

Turbulence is expected to play a relevant role in the so-called conductor gallop phenomena, namely, the highamplitude, low-frequency oscillation of overhead power lines due to the formation of ice structures and the ensuing effect that wind can have on these. In this work, the galloping time history of a wire with distorted (fixed in time) shape due to the formation of ice is analyzed numerically in the frame of a fluid-solid coupling method for different wind speeds and levels of turbulence. The results show that the turbulence intensity has a moderate effect on the increase of the conductor's aerodynamic lift and drag coefficients due to ice accretion; nevertheless, the corresponding changes in the torsion coefficient are very significant and complicated. A high turbulence intensity can affect the torsion coefficient in a certain range of attack angles and increase the torsion angle of the conductor. Through comparison of the galloping phenomena for different wind velocities, it is found that the related amplitude grows significantly with an increase of the wind speed. For a relatively large wind speed, the galloping amplitude is more sensitive to the turbulence intensity. Moreover, the larger the turbulence intensity, the larger the conductor's vertical and horizontal galloping amplitudes after icing. The torsion angle also increases with an increase in the wind speed and turbulence intensity. [ABSTRACT FROM AUTHOR]