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The operating wagon records were produced from distinct railway information systems, which resulted in the wagon routing record with the same oriental destination (OD) was different. This phenomenon has brought considerable difficulties to the railway wagon flow forecast. Some were because of poor data quality, which misled the actual prediction, while others were because of the existence of another actual wagon routings. This paper aims at finding all the wagon routing locus patterns from the history records, and thus puts forward an intelligent recognition method for the actual routing locus pattern of railway wagon flow based on SST algorithm.

Based on the big data of railway wagon flow records, the routing metadata model is constructed, and the historical data and real-time data are fused to improve the reliability of the path forecast results in the work of railway wagon flow forecast. Based on the division of spatial characteristics and the reduction of dimension in the distributary station, the improved Simhash algorithm is used to calculate the routing fingerprint. Combined with Squared Error Adjacency Matrix Clustering algorithm and Tarjan algorithm, the fingerprint similarity is calculated, the spatial characteristics are clustering and identified, the routing locus mode is formed and then the intelligent recognition of the actual wagon flow routing locus is realized.

This paper puts forward a more realistic method of railway wagon routing pattern recognition algorithm. The problem of traditional railway wagon routing planning is converted into the routing locus pattern recognition problem, and the wagon routing pattern of all OD streams is excavated from the historical data results. The analysis is carried out from three aspects: routing metadata, routing locus fingerprint and routing locus pattern. Then, the intelligent recognition SST-based algorithm of railway wagon routing locus pattern is proposed, which combines the history data and instant data to improve the reliability of the wagon routing selection result. Finally, railway wagon routing locus could be found out accurately, and the case study tests the validity of the algorithm.

Before the forecasting work of railway wagon flow, it needs to know how many kinds of wagon routing locus exist in a certain OD. Mining all the OD routing locus patterns from the railway wagon operating records is helpful to forecast the future routing combined with the wagon characteristics. The work of this paper is the basis of the railway wagon routing forecast.

As the basis of the railway wagon routing forecast, this research not only improves the accuracy and efficiency for the railway wagon routing forecast but also provides the further support of decision-making for the railway freight transportation organization.

Drawing upon affective events theory and regulatory focus theory, the current study examines the relationship between customer gratitude and customer-oriented organizational citizenship behavior (customer-oriented OCB), and the mediating role of positive affect and the moderating role of trait promotion focus.

Three-wave time-lagged data from 674 nurses nested within 125 department supervisors was collected. Multilevel modeling and Monte Carlo simulation were performed using Mplus 7.1 software to test all hypotheses.

Customer gratitude was positively associated with nurses’ customer-oriented OCB, and the relationship was mediated by positive affect. Nurse trait promotion focus strengthened the positive relationship between patient gratitude and positive affect, such that the relationship was stronger for those with a higher level of trait promotion focus.

This paper extends research on the effects of customer gratitude by extending our understanding of customer gratitude as a positive workplace event that can potentially promote employees’ positive behaviors toward customers, especially those with a stronger promotion focus.

This study is one of the first to examine the relationship between customer gratitude and employee customer-oriented OCB and uncover potential mechanisms to understand how this relationship unfolds and to whom this relationship is stronger. These findings can inform practices for service organizations.

Drawing on the work design growth model (WDGM), this paper aims to explore the relationship between job complexity and employee creativity through feedback-seeking and the moderating effect of team leaders with a growth creative mindset.

The authors used an online survey to test the hypotheses. Data was collected in three waves from 74 supervisors and 349 paired employees in China.

Job complexity had a positive association with employees’ feedback-seeking, which further linked to employee creativity. This indirect effect was stronger in work teams with leaders endorsing a growth creative mindset.

Job complexity has become prevalent in organizations today. Taking daily complexity as a resource for nurturing employee creativity may balance organizations’ costs on formal training and give them more initiatives in long-term development. In addition, as the growth creative mindset is relatively easy to assess and change, it may bring insights in terms of creativity development.

By empirically testing the behavioural mechanism of WDGM, the learning and development perspective of work design offers a new explanation of the relationship between job complexity and employee creativity. The authors further extend WDGM by identifying leaders’ growth creative mindset to be a boundary condition.

Urban parks play a key role in recreational activities, public health, and ecosystem services in urban areas. Using GIS and Fragstats, this study investigated the spatiotemporal dynamics of urban parks in Xi'an, China from 1949 to 2015 and the corresponding driving forces. The results show that the number and area of parks in Xi'an increased constantly during this period, especially from 2000 to 2015. Up to 2015, small green spaces, usually adjacent to streets, occupied the largest proportion among all types of parks. Archaeological parks were the largest in total area, but wetland parks were leading in average size of a single park. The density of parks was negatively correlated with their distance to the Clock Tower at the center of Xi'an. The dynamics of urban parks in highly urbanized areas were significantly different from that of their counterparts in suburban areas. Driving forces such as urban planning, urbanization and green space policies, and milestone events in the city's development jointly had a great effect on the distribution of parks in Xi'an. The research outcomes will support the upcoming Green Space Planning of Xi'an and benefit the pursuit of sustainability and human wellbeing.

The purpose of this study is to conduct research on a new kind of division microchannel heat sink (D-MCHS), which can distribute cooling water along the channel-length direction. First, the pressure drops in the D-MCHS with different division region numbers were compared. Then, the cooling performance of the D-MCHS with different division region numbers was also comparatively investigated. Finally, the temperature distribution on the bottom surface of the D-MCHS was analyzed.

First, experiments were conducted to investigate the numerical calculation method. Then, a three-dimensional steady, single-phase, laminar flow and solid-fluid conjugate heat transfer numerical model was used to research the flow and heat transfer characteristics in microchannels.

The pressure drop in the D-MCHS could be reduced by increasing the number of divided flow regions along the channel-length direction. The bottom average temperature of the D-MCHS could be simultaneously affected by the number of divided flow regions and the water flow rate. The thermal uniformity performance of the D-MCHS could be improved by increasing the number of division flow regions. The number of low-temperature and high-temperature areas on the bottom surface of the D-MCHS is corresponding to the division flow region number.

The D-MCHS exhibited a positive effect on the pressure drop decrease and thermal uniformity improvement. It not only keeps the electronic module working in a secure temperature environment but also consumes less pump power for a lower pressure drop.

This study aims to fabricate and manipulate ensemble spin of negative nitrogen-vacancy (NV⁻) centres optimally for future solid atomic magnetometers/gyroscope. Parameters for sample preparation most related to magnetometers/gyroscope are, in particular, the concentration and homogeneity of the NV⁻ centres, the parameters’ microwave antenna of resonance frequency and the strength of the microwave on NV⁻ centres. Besides, the abundance of other impurities such as neutral NV centres (NV⁰) and substitutional nitrogen in the lattice also plays a critical role in magnetic sensing.

The authors succeeded in fabricating the assembly of NV centres in diamond and they determined its concentration of (2-3) × 10¹⁶ cm⁻³ with irradiation followed by annealing under a high temperature condition. They explored a novel magnetic resonance approach to detect the weak magnetic fields that takes advantage of the solid-state electron ensemble spin of NV⁻ centres in diamond. In particular, the authors set up a magnetic sensor on the basis of the assembly of NV centres. They succeeded in fabricating the assembly of NV centres in diamond and determined its concentration. They also clarified the magnetic field intensity measured at different positions along the antenna with different lengths, and they found the optimal position where the signal of the magnetic field reaches the maximum.

The authors mainly reported preparation, initialization, manipulation and measurement of the ensemble spin of the NV centres in diamond using optical excitation and microwave radiation methods with variation of the external magnetic field. They determined the optimal parameters of irradiation and annealing to generate the ensemble NV centres, and a concentration of NV⁻ centres as high as 10¹⁶ cm⁻³ in diamond was obtained. In addition, they found that sensitivity of the magnetometer using this method can reach as low as 5.22 µT/Hz currently.

This research can shed light on the development of an atomic magnetometer and a gyroscope on the basis of the ensemble spin of NV centres in diamond.

High concentration spin of NV⁻ in diamond is one of the advantages compared with that of the atomic vapor cells, because it can obtain a higher concentration. When increasing the spin concentration, the spin signal is easy to detect, and macro-atomic spin magnetometer become possible. This research is the first step for solid atomic magnetometers with high spin density and high sensitivity potentially with further optimization. It has a wide range of applications from fundamental physics tests, sensor applications and navigation to detection of NMR signals.

As has been pointed out, in this research, the authors mainly worked on fabricating NV⁻ centres with high concentration (10¹⁵-10¹⁶ cm⁻³) in diamond by using optimal irradiation and annealing processes, and they quantitatively defined the NV⁻ concentration, which is important for the design of higher concentration processes in the magnetometer and gyroscope. Until now, few groups can directly define the NV⁻ concentration. Besides, the authors optimized the microwave antenna parameters experimentally and explored the dependence between the splitting of the magnetic resonance and the magnetic fields, which dictated the minimum detectable magnetic field.

In this paper, the authors aim to study the relationship between hydrogen embrittlement (HE) susceptibility and cathodic current density applied on the X70 steel girth welds.

The HE susceptibility of X70 steel girth welds were investigated through slow strain rate tensile test and observed and analyzed by optical microscope and scanning electron microscope methods.

The results show that HE susceptibility of X70 girth weld was basically unchanged with increasing of ion concentration while gradually increased and maintain at a specific value with the increase of cathodic current density. As for same ion content, a dense calcareous deposit layer generated on the sample surface in soil simulation solution with Ca2+ and Mg2+ resulted a decreased HE susceptibility while the porous calcareous deposit layer resulted a increased HE susceptibility.

A logistic regression model was established to describe the correlation between HE index and the cathodic current density.

We performed a bibiometric analysis on urbanization research based on the 3,058 peer-reviewed articles in the SCI and SSCI database from 1984 to 2013. Our analysis revealed document types, scientific outputs, subject categories, major journals and major authors, geographic distribution, highly cited papers and citation networks and temporal trends in keywords burst. Growth of article output has emerged since 1990, and went through two development stages. Environmental sciences, urban studies and ecology came out the most urbanization articles and Landscape and Urban Planning was the most productive journal in urbanization studies. Tothmeresz B was the most prolific author. USA was the most productive country, but Chinese Academy of Sciences was the most high-producing institution. Three streams were identified among the 65 most cited articles in the LCS historiography, and Schueler’s (1994) article has the strongest bursts. A keyword analysis revealed that the “China”, “city” and “globalization” are the research hotspots in the future.

This paper aims to introduce a novel four-dimensional hyper-chaotic system with different hyper-chaotic attractors as certain parameters vary. The typical dynamical behaviors of the new hyper-chaotic system are discussed in detail. The control problem of these hyper-chaotic attractors is also investigated analytically and numerically. Then, two novel electronic circuits of the proposed hyper-chaotic system with different parameters are presented and realized using physical components.

The adaptive control method is derived to achieve chaotic synchronization and anti-synchronization of the novel hyper-chaotic system with unknown parameters by making the synchronization and anti-synchronization error systems asymptotically stable at the origin based on Lyapunov stability theory. Then, two novel electronic circuits of the proposed hyper-chaotic system with different parameters are presented and realized using physical components. Multisim simulations and electronic circuit experiments are consistent with MATLAB simulation results and they verify the existence of these hyper-chaotic attractors.

Comparisons among MATLAB simulations, Multisim simulation results and physical experimental results show that they are consistent with each other and demonstrate that changing attractors of the hyper-chaotic system exist.

The goal of this paper is to construct a new four-dimensional hyper-chaotic system with different attractors as certain parameters vary. The adaptive synchronization and anti-synchronization laws of the novel hyper-chaotic system are established based on Lyapunov stability theory. The corresponding electronic circuits for the novel hyper-chaotic system with different attractors are also implemented to illustrate the accuracy and efficiency of chaotic circuit design.

The service performance for colored asphalt pavement is inevitably affected by the addition of different colorants, especially the challenge of low temperature environment in cold regions. Therefore, the purpose of study is to explore the effects of different colorants on the service performance for colored asphalt pavement and to provide a foundation for improving the applicability of colored asphalt pavement in cold regions.

In the study, three kinds of colorants (iron oxide red, iron oxide yellow, iron oxide green) were used to compare the influence of different colorants amounts and different colorants kinds on the service performance for colored asphalt pavement in cold regions. According to the characteristics of low temperature in cold regions, the effects of different colorants on the low temperature performance for colored asphalt pavement were studied.

The study shows that different colorants have different effects on the service performance of colored asphalt pavement. The high temperature performance increases with the increase of the colorants amount, but the low temperature performance is opposite. Additionally, the yellow colored asphalt pavement has more advantages of low temperature adaptation than the red and green colored asphalt pavement.

The study results provide a certain theoretical foundation for the application of colored asphalt pavement in cold regions and have certain value and significance for the further development of colored asphalt pavement.