Aiming at the advantages of U-shaped layout such as high production efficiency and strong flexibility, combined with the actual disassembly process that only needs to consider the required parts and hazardous parts, the U-shaped partial disassembly line balancing problem (UPDLBP) is proposed, and multi-objective mathematics model is established with the optimization objectives of minimizing the number of workstations, idle time balance indicators, disassembly depth and disassembly costs. On this basis, adaptive opposition-based learning multi-objective wolfpack algorithm (AOBL-MWPA) is proposed for solution calculation. The algorithm adopts adaptive scouting behavior and takes into account the global optimization performance in the early stage of the algorithm iteration and the stability in the later stage; The calling behavior and besieging behavior are discretized under the premise of satisfying the constraints of the priority relationship; Opposition-based learning strategy (OBLS) is used to avoid the algorithm from falling into the local optimum; Pareto solution set idea and crowding distance mechanism of non-dominated sorting genetic algorithm Ⅱ (NSGA-Ⅱ) are given to screen to obtain multiple non-inferior solutions. The proposed algorithm is applied to 19 benchmark examples and compared with existing literature algorithms. Finally, the proposed model and algorithm are applied to the example design of a U-shaped partial disassembly line of a certain automobile. The results show that, the proposed algorithm can solve the optimal value of small-scale problems in terms of the number of workstations on and the idle time balance index. The results obtained in medium and large-scale problems are better than other algorithms; the optimal value can be obtained for both the hazard index and the demand index, and the optimization rate is 100%. Ten sets of optional design schemes are obtained from the case study, which verifies the practicability and effectiveness of the proposed algorithm.

The tissue thermal effect of electrosurgical unit (ESU) can cause eschar on the surface of pancreatic tissue, which has the effect of hemostasis and preventing pancreatic fistula. The electro-mechanical parameters of ESU have a significant effect on the function of eschar hemostasis and preventing pancreatic fistula, but there is still a lack of in-depth study on the law of its action. In this study, three key electro-mechanical parameters, i.e. power, acting time and diameter of electrode front end, were studied in the DESICCATE mode by using in vitro simulation test method, combined with burst pressure test of pancreatic duct and eschar morphology analysis. Based on the above, the interaction between power, acting time and diameter of electrode front end was obtained by response surface analysis and the electro-mechanical parameters with the best effect of pancreatic duct sealing. The results show that the burst pressure of the pancreatic duct is at the peak value when the power is 60 W, the burst pressure of the pancreatic duct is at the peak value when the acting time is 2.00 s, and the burst pressure of the pancreatic duct is at the peak value when the diameter of the front end of the electrode is 2.00 mm. The best electro-mechanical parameters in the DESICCATE mode are: the power of electric knife is 59.39 W, the action time is 2.18 s, and the diameter of electrode front end is 2.31 mm. In addition, the diameter of the electrode front end is an independent factor affecting the pancreatic duct sealing effect, the power and acting time of the ESU have significant synergistic effect on the pancreatic duct sealing.

This work aims to overcome the shortcomings of the traditional TOPSIS (technique for order of preference by similarity to an ideal solution) method, which cannot exclude the interference from correlation among indexes that can easily complicate decision-making operations during optimal selection of mountain railway location designs, and thus enable full consideration of any uncertain characteristics during decision-making. First, the Mahalanobis distance was used to replace the Euclidean distance in traditional TOPSIS, thus achieving the first improvement in TOPSIS. Then, the correlation coefficient matrix was used to replace the covariance matrix in the Mahalanobis distance, which represents the second improvement in the TOPSIS method. Then, linguistic fuzzy numbers, interval numbers, and a cloud model were used to achieve quantification of the qualitative indexes, and a comprehensive optimization model for mountain railway location design was constructed based on the twice-improved TOPSIS method. Finally, the comprehensive optimization model was applied to the partial route direction scheme of the Batang to Changdu section of a specific mountain railway. The results show that the twice-improved TOPSIS method can effectively exclude the interference from the correlation among indexes and thus simplifies the decision-making process. In addition, application of the cloud model can overcome the deficiency in the decision-making method with regard to its ability to deal with the uncertainty of qualitative language. The application results from the comprehensive optimization model coincide with the recommended results of the pre-feasibility study of the mountain railway, i.e., the optimization results from both approaches lead to the route scheme passing through Baiyu and Jiangda, thus indicating that the proposed model can be used as a new approach for route direction optimization in future mountain railway location designs.

To prevent derailment in No. 6 symmetric turnouts, a vehicle-turnout dynamic model is built on the basis of the structural characteristics of the guard rail in front of the turnout and the working principle of a new anti-derailment equipment in turnouts. Through the vehicle-turnout coupling model, the influences of the guard rail and preventing derailment structure on dynamic responses of the turnout are simulated and discussed. The results show that both the guard rail and the new anti-derailment equipment can effectively constrain the lateral shift of the wheelset when negotiating the turnout, and change the wheelset trajectory, making the wheel flange contact switch rail at 0.493 and 0.705 m away from the switch rail toe, respectively, and preventing the wheel flange from contacting the switch rail toe. Thus, the adverse contact status between wheel flange and switch rail toe can be avoided, and the safety of turnout negotiation is improved significantly. When there are guard rails installed on both sides of the track, the increased wheel flangeway width will cause the guard rail to reduce its restraint effect on the wheelset and lose its protective function. The new anti-derailment equipment extends into the turnout and can be installed symmetrically on both sides of the track, which ensures the driving safety in both directions of the symmetrical turnout and effectively avoids derailment occurrences in the No. 6 symmetrical turnout area.

A section on a ballasted passenger dedicated line is targeted, where the periodic longitudinal unevenness occurs with the wavelength of 3.2 m, leading to vehicle shaking. Based on the synchrosqueezed wavelet transform, the time-frequency distribution of the dynamic and static track geometry detection data before and after machine tamping is extracted. Combined with the analysis on rail straightening process, the causes of periodic longitudinal unevenness are clarified, which may be caused by poor composite straightening process in rail rolling. On this basis, the relationship between rail straightening irregularity, vibration acceleration of vehicle components, and wheel rail contact force are explored, and the influence of rail straightening irregularity on vehicle dynamic performance is obtained. The results show that the coherence functions of vertical accelerations at axle box, bogie and car body are 0.97, 0.96 and 0.76 respectively, which increase 5%, 25% and 300% respectively than that on the normal section. The coherence function of wheel rail vertical force is increased by 42% to 0.94, revealing that straightening irregularity is closely related to the vibration response of vehicle components and wheel-rail contact force. Due to straightening irregularity, the RMS value of vertical acceleration at axle box and car body are amplified by about 1.00 m/s² and 0.05 m/s² respectively. Straightening irregularity has a strongest linear correlation with the RMS values of vertical accelerations at axle box and wheel-rail vertical force with the correlation coefficients of 0.9 and 0.8 respectively.

The coupled vibration of vehicle and track has a significant effect on the traction and braking effectiveness of trains when they pass through long steep grades. A vehicle-track coupled dynamics model considering train traction/braking behavior and the horizontal/vertical profile of the track is formulated, which is applied to study the dynamic behavior of a train passing through long steep grades. The proposed numerical model is validated by experimental data, which is also validated by comparing with the traditional calculation method. The proposed model is then used to evaluate the running capability of a high-speed train on the steep grades of Xi’an−Chengdu high-speed railway. The result shows that the proposed three-dimensional (3D) method can predict the influences of steep grades on the speed variation and dynamic performances of the trains. Traditional one-dimensional (1D) model underestimates the speed reduction value of the trains travelling on steep grades. The estimated value of speed reduction calculated by 1D method was around 5% less for every 10 kilometers than that calculated by 3D method. A serious deceleration phenomenon occurs when the CRH3A train running through the long steep grades of Xi’an−Chengdu high-speed railway. When the traction power is increased by 50%, the amount of sections where the reduction of speed over 20% is reduced by 7, and the total running time of the trains is 13% fewer. The trains with higher power traction should be adopted to increase the operational efficiency and enhance curving performance when passing through Xi’an−Chengdu high-speed railway.

In the process of fine adjustment, maintenance and repair to tracks, it is frequent to adjust only the height, direction, level, distortion and other relevant factors, but there are few relevant regulations on rail cants. It is found that the measured rail cants on a section of a passenger dedicated line vary greatly. By establishing a model of a 250 km/h EMU vehicle, given that the LMD wheel profile matches the standard 60 kg/m (CHN60) rail, the vehicle dynamic behavior is analyzed in the condition of the same track with standard (1∶40), symmetrically changing, and asymmetrically changing rail cants. The calculation results show that the symmetrical and asymmetric changes of the rail cant have a great impact on the stability and comfort of the vehicle when it runs in a straight line. Compared with the standard rail cant (1∶40), the symmetrically and asymmetrically changing rail cants increase vertical stability index by 32.96% and 34.52%, respectively, and the maximum lateral stability index by 40.65%. Wheel wear increases gradually with the sequence of the standard, symmetrical changing, and asymmetric changing rail cants. Compared with the standard rail cant, the asymmetrically and symmetrically changing rail cants on the straight section increases the maximum wear index by 136.71% and 27.65% respectively, and the maximum surface fatigue index by 25.14% and 15.86% respectively. For the symmetrically and asymmetrically changing rail cants, the vehicle lateral shaking is increased. In contrast to the standard rail cant, wheel wear and fatigue index on the curved section are less affected by the variation of rail cants, but they are more influenced on the curved section than those on the straight section. Finally, according to the above conclusions, the practical suggestions for rail cants are put forward.

The carbody is an important load-bearing component of metro vehicles. In view of the high comprehensive difficulty of the full-scale carbody fatigue test, on the basis of the characteristics of the end underframe model including the most severely stressed structures in the carbody (e.g., the draft, bolster and buffer), adoption of a fatigue test method using an end underframe submodel is proposed instead of the full-scale carbody. Finite element models of the end underframe and the full-size carbody are established, and the fatigue loads are determined according to the EN 12663 standard. The end underframe model and the stress distribution at key positions of the full-scale carbody are made consistent by setting reasonable boundary conditions. The stress at key positions of the end underframe is measured in a test, and a comparison is made with simulation results to verify the accuracy of the finite element model. The nominal stress method and the S-N curve specified by Eurocode 9 are then used to calculate the fatigue damage to the carbody and underframe welding seams. The results show that the three positions of maximum damage for the end underframe are consistent with the full-scale carbody, and the damage to the end underframe at the same position is greater than the damage to the carbody. Therefore, the fatigue life evaluation of the full-scale carbody using the submodel method readily obtains conservative results, and it is feasible to use the submodel method to evaluate the fatigue life of a metro carbody.

The Sichuan−Tibet railway is built under some difficult situations, including limited ballast bed profile, frequent earthquakes and large diurnal temperature variation. These difficulties cause insufficient lateral resistance of ballasted track, which is an urgent problem for the stability and resilience of the continuously welded rail (CWR). Aiming to improve and quantify the stability and resilience of CWR, the lateral resistance of frictional sleepers (designed as that normal sleeper with arrowhead shape groove) is evaluated with the single sleeper push test (SSPT). By performing SSPT, the increment of lateral resistance of ballast bed with frictional sleepers is measured. Shapes of sleeper grooves are properly designed and optimized (three groove shapes with the same size and volume but different arrowhead directions). Whether frictional sleeper applied to ballast bed (reduced ballast shoulder width) will provide enough lateral resistance for the ballast bed at Sichuan−Tibet railway line. Results show that frictional sleepers can increase the lateral resistance by minimum 7% and maximum 21%. Arrowhead directions significantly influence the lateral resistance, which is increased by 7% (same pushing direction) and 24% (opposite pushing direction), compared to normal sleepers. Therefore, strict attention should be paid to the laying direction when laying in curved sections of ballasted track. After reducing the ballast shoulder width from 50 cm to 30 cm, using the frictional sleeper (single arrowhead direction pushed in reversed direction) can still provide enough lateral resistance, which is the same value as a mono-block Type Ⅲ sleeper with 50 cm shoulder width.

Existing methods for detecting deformation of high-speed railway slab ballastless tracksis low in efficiency and high in cost, while the track dynamic geometry inspection data can reflect the deformation level of slabs in a way.In this work, the track dynamic inspection data of railway lines of CRTS Ⅰ, Ⅱ, Ⅲ slabs within three years were collected and the wavelet energy was used as the deformation evaluation index of track slab. Finally, a temporal-spatial data mining model was proposed to realize the recognition and degradation prediction of track slabs. The results show that, affected by the local air temperature, the deformationlevel of track slabs has a seasonal pattern.Type-Ⅰ and type-Ⅱ slabs display warping and arching deformation in a high-temperature environment, while type-Ⅲ slab shows frost heavingin a low-temperature environment. Of the three types of track slabs, the deformation level of type-Ⅰ slab is mild, while the type-Ⅱ slab is most severe. The residual deformation of type-Ⅱ slab will accumulate over time, which may eventually lead to surface irregularity exceeding the limit. The long-term and short-term memory network can realize short- and mid-term prediction of the track slab deformation within 15 to 30 days. The the best predictionR-square value of the type-Ⅰ platedeformation is close to 0.9, while that of the type-Ⅱ and type-Ⅲ plate deformations exceeds 0.9.

In order to establish a constitutive model that can accurately simulate the whole deformation and failure process of rock, a deep analysis is made of the limitations of the existing statistical damage models incapable of well describing the initial nonlinear phase of rock deformation. Considering the deformation mechanism of rock comprehensively, the intact rock is abstracted as a material composed of rock skeleton and voids. Based on the analysis of the deformation relationships among the whole rock, rock skeleton and voids, the concept of rock void strain ratio K is proposed; the calculation methods of rock skeleton strain and voids strain are presented using triaxial test results to derive the evolution equation of K. By introducing the statistical damage theory, the rock is regarded as being composed of many micro elements whose strength obeys the distribution of Weibull function. Finally, a new constitutive model is established to describe the whole rock deformation process, and the determination methods of relevant model parameters are given. Compared with other model calculations and test results, this constitutive model can better simulate the five phases of the whole rock deformation and failure process under load, and the correlation coefficients are all larger than 0.92 for different confining test results. It also well explains the mechanical behavior characteristics that the larger the confining pressure, the shorter the initial void closure phase, and the larger the elastic modulus, peak strength and peak strain.

The stratum of the Huoshan tunnel mainly distributes sandstone and mudstone intrusive by granodiorite. The tunnel axis passes through the granitic intrusive rock area where the lithology changes drastically, and the distribution of initial geostress is complicated. Back analysis the characteristics of the initial geostress field in the intrusive rock mass area based on the measured geostress data can further guide the design and construction. A three-dimensional numerical model is established depending on the geological survey data of the Huoshan tunnel. The initial geostress data of borehole is measured by the hydraulic fracturing method, multivariate linear regression method is used to obtain the initial geostress field in engineering area. The distribution of initial geostress near the granodiorite intrusion surface is discussed. The results show that the distribution of the initial geostress field in granitic intrusive rock is very complicated. Both the magnitude of the principal stresses and the direction of the horizontal principal stresses inside and outside the intrusive bodies have changed dramatically (the change range of the principal stress magnitude is about 2.0−5.3 MPa, and that of the principal stress angle is about 50.7°−178.8°). Burial depth and distribution of intrusive body have become important factors affecting the distribution of initial geostress field, and the larger the burial depth or the smaller the cross section of the intrusive rock body, the larger the initial geostress value; At the same time, the front area of the intrusive body was significantly impacted by compressive tectonics, and stress concentration is more obvious.

The distribution law of ground stress has a very important role in the construction of underground engineering, and obtaining the distribution of ground stress field in the construction area is of great significance to guide the design of support structure. The borehole hydraulic fracturing method was used to test the in-situ stress in the project area of a railway tunnel in Xianshuihe fault belt. Based on the in-situ stress results, the variation law of in-situ stress with depth was obtained and the in-situ stress inversion was carried out by numerical simulation. The results show that the in-situ stress increases gradually with the increase of depth, in which the increasing gradient of the maximum horizontal in-situ stress is 0.385 MPa/km, and that of the minimum horizontal principal stress is 0.257 MPa/km. The maximum and minimum horizontal principal stress values of the tunnel profile are 41.69 and 29.84 MPa, respectively. The lateral pressure coefficient is 1.363−1.438, and the surrounding rock stress is dominated by horizontal stress. Generally, the in-situ stress has been released to a certain extent in the fault area, and the stress of the intact rock mass on both sides of the fault is concentrated to a certain extent with a high stress value.

When a shield tunnel under construction is below the water level, the shield backfill grouting slurry will drive the groundwater. In order to analyze this driving process, the seepage path of slurry in the soil is generalized to a capillary by capillary group penetration theory, the grout diffusion radius of hemispherical and cylindrical models are deduced considering the diffusion by Newtonian fluid slurry-driven water (Newtonian fluid), and the effects of grouting pressure, water-cement ratio, and formation permeability coefficient are discussed. Results show that the grout diffusion radius is mainly related to the grouting pressure, permeability, grouting time, porosity, and grout and groundwater viscosity. Especially, the grout water-cement ratio has the most significant effect on the grout diffusion radius. When the viscosity of the grout decreases from 0.004 7 to 0.001 9 Pa•s, the spreading radius of grout decreases by 46.7% at 1 h after grouting, indicating that the spreading radius of grout can be increased by adopting a higher water-cement ratio under the same grouting condition. Besides, the grout diffusion radius increases with an increase in the permeability coefficient, and the formation permeability coefficient reflects the difficulty of grout diffusion to a certain extent. Based on the calculation of grout diffusion radius (grout reinforcement range), a calculation method for the lower limit of the grouting pressure is proposed to guide the construction of backfill grouting of shield tunnel.

In order to predict the arrival time and wave height of the shock wave (surge) from a landslide source to the hazard-affected body, the near-field wave characteristics of the surge induced by the reservoir rock mass landslide were experimentally studied. Firstly, according to the typical rockslide parameters and rock fracture characteristics in the Three Gorges reservoir area, a three-dimensional physical laboratory model for cracked rockslide generated impulse waves was built based on the generalized Froude similarity. Then, the near-field wave generation mechanism and propagation law were revealed though model tests. Finally, a prediction model of near-field waves was established by multiple regression analysis. The results showed that the main driving force of the first wave is the displacement and drag of the landslide to the water body; the size of the leading wave trough amplitude depends on the duration of the water collapse. According to the underwater movement process of the landslide, two critical water depths are introduced in this paper, and the calculation method of the first wave trough generation time is proposed. Furthermore, the first wave crest propagates at velocities up to the approximate solitary wave celerity. The celerity of the first wave trough and the second wave is lower than that of the solitary wave, and their measureless phase wave speeds are 0.9, 0.78 and 0.68 times the solitary wave celerity, respectively.

In order to study the mechanical behavior of different forms of enclosed sound barriers under wind pressure generated by high-speed trains, taking a high-speed rail sound barrier as the research object, global models for the double-sided enclosed sound barrier structure with different top opening spacing and for the single-sided enclosed sound barrier structure with different top covering lengths were established using the finite element software Midas. The pulsating wind pressure generated by the train passing by at a speed of 350 km/h were applied to the global model of the sound barrier structures as excitations, the static response and dynamic time history curves of the sound barrier structures were calculated, and then the dynamic amplification factors were obtained. The results show that the increase of the opening spacing on the top of the double-sided enclosed sound barrier and the reduction of the top covering length of the single-sided enclosed sound barrier are both beneficial to the release of wind pressure and improvement of structural stress. As the opening spacing increases or the covering length decreases, the beneficial effect becomes more obvious. For the double-sided enclosed sound barrier structure, the maximum dynamic stress of the columns with 2 m top opening spacing is 1.15 times that with 8 m opening spacing, and the amplification factor also increases by 0.12. For the single-sided enclosed sound barrier structure, the maximum dynamic stress of columns with 8 m top covering length is 1.28 times that with 2 m top covering length, and the magnification factor increases by 0.37.

In order to obtain the concentration distribution of chloride ions in cracked concrete and analyze the influence of crack shape, distribution form and deflection angle on the chloride ion diffusion in concrete, a cellular automata model for simulating the diffusion process of chloride ions in cracked concrete is established by using cellular automata and homogenization equivalent analysis methods according to the diffusion mechanism of chloride ions in cracked concrete; the cell size in the model is optimized by numerical experiments. The results show that the computational efficiency of the model can be improved with a high calculation accuracy when the cell size of is 0.5 mm. Except for individual data, the model simulation results are in good agreement with the test results and finite element analysis results, and the maximum deviation is no more than 10%. The chloride ion concentration in the "V" crack is about 0.52 times that in the rectangular crack. The chloride ion concentration in curved cracks and broken line cracks is about 0.87 times and 0.89 times that in linear cracks, respectively. When the fracture deflection angle increases from 0° to 10°, 20°, and 30°, the chloride ion concentration at the fracture end decreases by 3.3%, 21.9%, and 29.8%, respectively. The influence range of the crack on the chloride diffusion zone around the crack is independent of the shape, distribution form, and deflection angle of the crack. The influenced area is mainly concentrated on the range of about 18 mm perpendicular to the crack.

In order to study the pipeline gravity transport law of high-concentration mixed aggregate filling slurry, an industrial test was carried out using the filling pipeline transport system of a nickel mine in Gansu Province. Firstly, the pipeline resistance of slurry under different conditions was obtained through industrial test, and the relationships between pipeline resistance and slurry velocity, slurry concentration and content of stone powder were analyzed. Then, based on the assumed independent nature of variables, a mathematical model of pipeline resistance was established, and the interaction of influencing factors of pipeline resistance was discussed. Finally, the results of pipeline resistance were verified and analyzed by rheological test and mechanism research. The results show that the pipeline resistance increases linearly with the slurry velocity, increase as a power function with the slurry concentration, and decreases first and then increases, namely in parabolic fashion, with the addition of stone powder. When the stone powder content is 30%, the pipeline resistance is the minimum. Interacted influencing factor pairs of pipeline resistance, ranked by interaction from large to small, are slurry concentration and flow velocity, stone powder content and flow velocity, and stone powder content and slurry concentration, resulting in the pipeline resistance varies in range of 2070−6920, 2180−5970, and 3140−5530 Pa/m, respectively. In addition, the rheological parameters increase with the increased slurry concentration, and decrease first and then increase with the increase of stone powder content, which verifies the variation law of pipeline resistance. The reasons for the change of slurry rheological characteristics and pipeline resistance include the vibration effect of flow velocity, the viscous effect of concentration and the flocculation theory of stone powder.

To study the influence of local deformation of asphalt pavement on riding quality, the vibration serviceability under three types of local deformation, joint faulting type, double-section type and curved surface type, which are common in pavement maintenance management, was evaluated. Firstly, simplified profile model of local deformations are established, and vertical vibration accelerations of human body with the excitation of local deformations are derived, based on the quarter car model. Then, the vertical accelerations are filtered with designed frequency-weighted filter, and instantaneous frequency-weighted accelerations are hence obtained, root-mean-square accelerations under different working conditions are calculated, and weighted vibration serviceability evaluation in time-domain is achieved. Finally, evaluation criteria of local deformations are proposed. The results show that, root-mean-square acceleration is directly proportional to height difference of local deformation. Under the same deformation degree, the driving experience of double-section deformation is the worst. When local deformation height difference of joint faulting, double-section and curved surface reaches 4.76, 2.78 and 3.26 cm, respectively, riding quality reaches extremely uncomfortable states.

In practical applications, inverter feedback devices work in intermittent duty, and its working characteristic model must be considered when determining its location and capacity design in the power supply calculation. Thus, an AC/DC alternating iterative power flow calculation algorithm with intermittent duty of inverter feedback devices is proposed for urban rail transit. A power-based dynamic adjustment strategy is proposed to realize state transition in the operation of inverter feedback devices. The full-day energy consumption is calculated for the entire line starting from the main substation, and the influences of the starting voltage of different inverter feedback devices, the no-load voltage of the rectifier unit and the number of train departures affect are analyzed. The whole line of an actual metro project is simulated and the simulation results prove that the proposed algorithm is more consistent with the load process of the inverter feedback devices in actual project. The statistical results show that the starting voltage of the inverter feedback devices will affect the system energy saving, and a proper starting voltage have a significantly favorable effect on the energy saving of the power supply system equipped with inverter feedback devices, which can save 12.23% of the energy consumption compared with the system without inverter feedback devices; when the no-load voltage of the rectifier is high, or when there are few trains, the starting voltage of the inverter feedback device should be reduced accordingly to obtain a better energy saving effect.

As the testing model of railway signal system software fails to describe the test requirements systematically, a risk timed statechart (RTSC) modeling method is proposed. First, the characteristics of testing railway signal system software are analyzed, and its modeling requirements are proposed. Then, based on the finite state machine (FSM) theory, the clock and risk level elements are extended respectively in the transition and state of the FSM, and the RTSC modeling method is proposed to meet the modeling requirements of the functional logic, clock constraint and risk level. The formal definition and configuration mechanism of the RTSC are expressed by Z notation. Finally, the switching function of computer-based interlocking system is used as an example to build the RTSC testing model and the proposed method is compared with the timed automata modeling method. The results show that in contrast to the timed automata modeling method, the RTSC saves 62% of transition numbers and has stronger description ability, which can meet the modeling requirements of the railway signal system software testing.

In order to study the drivers’ attention allocation on the interface of high-speed railway control console, and finally achieve the purpose of optimizing the interface layout design of high-speed railway control console, the CRH380D train simulation platform was adopted, and the attention allocation of 14 drivers in the Chengdu locomotive depot high-speed train application workshop was measured by simulated driving experiment. Firstly, the driver’s on duty process was divided into three tasks: departure preparation, main line driving, and parking braking. Secondly, eye movement data, operation trajectory, and NASA-TLX subjective workload of the tested subjects in the three tasks were collected from the visual, behavioral, and psychological layers respectively. Finally, combined with the in-depth interview with the tested subjects, the attention allocation of the drivers to the CRH380D train control console interface was obtained. The results show that, in the current interface layout design of CRH380D train control console, ATP is the highest concentration distribution, followed by TCMS1. Among the 21 switch buttons on the horizontal control surface, the ones that attract more attention are the driving door, the parking brake, and the lifting/lowering buttons. Driver’s eye movement trajectory map and operation trajectory map are more complex, and driver's subjective workload is relatively high. According to the experimental results, four principles of interface layout design for high-speed railway control console and some corresponding design suggestions are summarized. Taking CRH380D train as an example, the optimal design scheme of high-speed railway control console interface layout is obtained.

To enable intelligent connected vehicles (ICV) pass through signalized intersections efficiently and safely in complex traffic environments, on the basis of real-time acquisition of signal lights and preceding vehicle status information in the internet of vehicles, the driving behavior decision framework of ICV through signalized intersections in the ICV environment was established.The car-following model was used to derive the future driving status of ICV and vehicles ahead,then to predict whether the preceding vehicles will pass through the intersection, and further to judge the conditions for passing the intersection stop line when the ICVis the leader or the follower.The lane change was addedin the driving mode toseek higher traffic efficiency, and the method based on the lane change time model was used to judge the passing conditions after the ICV changesa lane.Through simulation comparison, the decision-making ability of the proposed model and the existing model was analyzed, the key factors that affect the decision-making process were discussed. Compared with the existing model, the decision method of combining signal lights and the driving intention of the preceding vehicle can improve the judgmentaccuracy of ICVs on passing conditions and realize reasonable decision-making.With the increasing of the remaining time per unit green light, the probability of vehicles passing through the intersection can be increased by 20%, and vehicle positions in the current lane have significant influence on decision result.

To explore the characteristics of delayed boarding in metro stations, a probability distribution estimation method based on auto fare collection (AFC) data and operation timetable data is developed. Firstly, according to the relationship between passenger tap-in and tap-out time and train arrival and departure time, a probability distribution function of maximum access time and egress time is constructed, and an estimation method using the truncated sample is developed to estimate the access and egress time distribution. Secondly, an estimation method of the delayed-boarding probability distribution is constructed by analyzing the relationship among passenger tap-in and tap-out time, access and egress time and the number of delayed-boarding times. Finally, with some metro sections as a real case study, for different levels and types of stations, the access and egress time distribution and the delayed-boarding probability are estimated. The results of the case study show that the access and egress time distributions follow the estimated distributions at a 5% significant level, and the estimated delayed-boarding probability distribution is consistent with the practical results.

A two-sided matching method that considers the overall satisfaction and individual satisfaction of supply and demand sides is proposed to solve many-to-many matching problem in logistics service with complete preference ordinal information. Firstly, considering the matching balance of both sides, a two-stage optimization model of many-to-many supply-demand matching is constructed for logistics services. Then the Pareto solution set of the tow-sided matching is obtained by solving the model with the multi-objective genetic algorithm. Finally, the logistics service outsourcing in a certain region is used as an example, and in this case, without considering the individual satisfaction, the variance of individual satisfaction of the demander and the supplier is 0.57 and 0.22 respectively; when the threshold value of individual satisfaction is 0.22, a matching scheme that achieves the balance of individual satisfaction can be obtained. If the balance of overall satisfaction and individual satisfaction is taken into account, it is possible to ensure the overall optimization and better balance the matching satisfaction between the two sides of supply and demand in logistics services, and guide decision makers to obtain an optimal satisfactory match between supply and demand.

At present, there are no specified rules that clarify the relationship between the arrangement of LED lights, spacing of LED lights, curvaturer adius, and blind area. Thus, the maximum allowable spacing and maximum blind area are explored in terms of different luminaire arrangements with the two constraints of flicker frequency and blind area boundary. First of all, according to four luminaire arrangements, i.e., outside unilateral arrangement, inside unilateral arrangement, symmetrically bilateral arrangement, and alternate bilateral arrangement, the expression with respect to the blind area, luminaire spacing and tunnel curvature radiusis obtained with the aid of plane geometry, and through partial differential, their relationships are determined. Secondly, the relationship between the maximum allowable spacing and the parameters of the blind area boundary (car length and car width) is analyzed with the blind area boundary as the main constraint. Finally, by partial differential or algebraic method, different car types are used as examples for verifying the maximum allowable blind area and maximum allowable luminaire spacing with different luminaire arrangements. It is found when either the luminaire spacing or the curvature radius is settled, the blind area increases with the luminaire spacingor curvature radius.In the case of inside unilateral arrangement, the luminaire spacing increases with the car length or curvature radius. For outside unilateral arrangement, it increases with the car length or curvature radius, while decreasing with the car width. If the blind area is considered for bilateral arrangement, the luminaire spacing does not meet the requirements, indicating that only if luminaire spacing is large enough, the blind area exists. Through the comparison of different car models, it is concluded that inside unilateral arrangement is desirable for unilater alluminaire arrangement, and both symmetrically bilateral arrangement and alternate bilateral arrangement are acceptable for bilateral luminaire arrangement.

With the rapid development of economy and technology, indoor spaces are becoming more and more complex, and the demand for indoor location services is increasing. There are more and more indoor map products as information carriers of location services. However, most of the indoor maps present more contents than what users need. In response to this problem, a method is proposed to explore the factors affecting the importance of indoor space elements on the basis of user needs. This method uses spatial cognition theory to conduct multiple psychological behavior experiments in different indoor spaces, analyzes the results of experiments within and between groups, extracts the generality of user needs, and obtains influential factors for indoor space elements. By experiment verification, the influencing factors are determined: element visibility, spatial location distribution, element uniqueness and relative scale.

In the development and protection of traditional villages, building renovation and layout change for fire prevention may cause the changes in fire risk. Fire spread simulation is marked by large workloads, high costs and difficulty in acquiring basic data. To cope with these, first, the single building is regarded as the node of the directed graph, and the fire spread relationship between buildings as the edge between nodes. The local spread path around the node is judged through the fire spread simulation, the adjacency matrix of the directed graph is established, the spread range under a specific fire scene is determined by the traversing directed graph algorithm, and the loss expectation for the multiple fire spread scenarios is presented. The adjacency matrix of the directed graph is modified by adding and deleting nodes or edges to reflect the changes of building renovation and addition and trees on the fire spread relationships, and the traversing algorithm of nodes is reused to determine the fire spread risk of the buildings. Finally, a traditional village is used as an example to verify the proposed method. The results show that the proposed method can quickly calculate the fire spread risk of the dynamically changing village buildings and reduces the workload of fire spread re-simulation. In terms of fire spread prevention and control, the maximum loss and loss expectation of fire spread between buildings can be respectively reduced by 61.9% and 52.1% through improving fire preventions of 6 highly-risky nodes. For building planning or management, it is necessary to avoid the case of new buildings, trees and other combustible materials locating in densely built areas or link-nodes connecting multiple densely built areas.