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To solve problems of low intelligence and poor robustness of traditional navigation systems, the purpose of this paper is to propose a brain-inspired localization method of the unmanned aerial vehicle (UAV).

First, the yaw angle of the UAV is obtained by modeling head direction cells with one-dimension continuous attractor neural network (1 D-CANN) and then inputs into 3D grid cells. After that, the motion information of the UAV is encoded as the firing of 3 D grid cells using 3 D-CANN. Finally, the current position of the UAV can be decoded from the neuron firing through the period-adic method.

Simulation results suggest that continuous yaw and position information can be generated from the conjunctive model of head direction cells and grid cells.

The proposed period-adic cell decoding method can provide a UAV with the 3 D position, which is more intelligent and robust than traditional navigation methods.

The aim of this paper is to better understand the generation and transmission mechanism of the electromagnetic acoustic transducer (EMAT).

A semi-analytical method was used to calculate the Lorentz force. Both the hypothetical magnetic field mirror method and the diffusion equation were adopted to solve the eddy current distribution by variables separation method in time domain. A three-dimension magnetostatic finite element model was used to calculate the static magnetic field and the relative permeability. And an experimental platform with a piezoelectric probe to generate and an EMAT to receive, the ultrasonic wave was set up to verify the distribution of the Lorentz force.

The Lorentz force at different time and in different positions of the steel plate can be easily calculated. The experimental results show a good agreement with the analytical results.

The accurate prediction of the Lorentz force provides an insight into the physical phenomenon of EMAT and a powerful tool to design optimum EMAT.

The Embedded GPS/INS System (EGI) has been used more widely as central navigation equipment of aircraft. For certain cases needing high attitude accuracy, star sensor can be integrated with EGI to improve attitude performance. Since the filtering‐correction loop has already built in finished EGI product, centralized or federated Kalman filter is not applicable for integrating EGI with star sensor; it is a challenge to design multi‐sensor information fusion algorithm suitable for this situation. The purpose of this paper is to present a double‐layer fusion scheme and algorithms to meet the practical need of constructing integrated multi‐sensor navigation system by star sensor assisting finished EGI unit.

The alternate fusion algorithms for asynchronous measurements and the sequential fusion algorithms for synchronous measurements are presented. By combining alternate filtering and sequential filtering algorithms, a kind of double‐layer fusion algorithms for multi‐sensors is proposed and validated by semi‐physical test in this paper.

The double‐layer fusion algorithms represent a filtering strategy for multiple non‐identical parallel sensors to assist INS, while the independent estimation‐correction loop in EGI is still maintained. It has significant benefits in updating original navigation system by integrating new sensors.

The approach described in this paper can be used in designing similar multi‐sensor information fusion navigation system composed by EGI and various kinds of sensors, so as to improve the navigation performance.

Compared with conventional approach, in the situation that centralized and federated Kalman filter are not applicable, the double‐layer fusion scheme and algorithms give an external filtering strategy for measurements of finished EGI unit and star sensors.

The purpose of this paper is to expound the concept of the coordinated development of the transport system, and provide a quantitative method to support decision making in urban transportation development planning.

To analyze the organic composition of urban transport system, research the meaning and mechanism of coordinated development of transport system. On the basis of researching relations of transport and external systems and its subsystems, to research quantitative theoretical model of the coordinated development and assessment of the transport system.

Establishing models needs to analyze the coordination among the various indices of subsystem, calculate the overall coordination between indices of the subsystem and all the indices of other subsystems, then inspect the coordinated development among subsystems.

How to design the indexes of the subsystem of urban transport system is the main limitation.

Offering theoretical foundation for coordinated development of urban transport system.

Putting forward quantitative theoretical model on coordinated development of urban transport system, which lays a foundation for further study.

The federated filter created by Carlson has been widely used in multi-sensor integrated navigation. Compared with no-reset federated filter, the reset mode has greater sub-filters’ performance, but faults of any subsystem would affect other healthy subsystems via global fusion and the sub-optimality of sub-filters’ estimation has influence on fault detection sensitivity. It’s a challenge to design a robust reset federated filter.

The time-varying observation noise is designed to reduce proportions of observation information in faulty sub-filters. A new dynamic information distribution algorithm based on optimal residual chi-square detection function is presented to reduce proportions of faulty sub-filters’ estimation in information fusion filter.

The robust filtering algorithm represents a filtering strategy for reset federated filter. Compared with fault isolation, the navigation result is smoother by using this algorithm. It has significant benefits in avoiding faulty sensors’ contamination and the performance of federated filter is greatly improved.

The approach described in this paper provides a new method to deal with federated reset filter’s faulty problems. This new robust federated filter algorithm possesses a great potential for various applications.

The approach described in this paper can be used in multi-sensor integrated navigation with no fewer than three sensors.

Compared with conventional approach of fault isolation, the proposed algorithm does not destroy the continuity and integrity of the filtering process. It improves the performance of the federated filter by reducing proportions of faulty observation information. It also reduces the influence of sub-optimality on fault detection sensitivity.

The purpose of this paper is to investigate logistics activities in Singapore hospitals. It defines various types of activities handled by a logistics division. Inventory management policy and the use of information and communication technologies (ICT) for logistics purposes are also discussed. The study identifies the nature of strategic alliances in Singapore's health care industry.

This study was conducted by utilizing a framework for data collection, pre‐testing the questionnaire and conducting interviews. Various relevant literature was reviewed to design the questionnaire.

This study finds that logistics division carry out many related activities and some of them also provide engineering services. The hospitals make use of ICT. The hospitals are clustered under various groups to minimize the cost of operation, including the logistics related costs. However, hospitals do not see alliances with suppliers as a strategic option; rather they focus on outsourcing of logistics services. The findings also show that Singapore hospitals have a good stocking policy for both medical and non‐medical items so that changes in patient mix can be easily handled.

Singapore is continuously improving its health care industry and therefore, the findings will help hospitals in other regions to adopt some of the practices, like concentrating on local vendors, outsourcing, clustering, and maximum use of information technology as competitive factors that can improve the service and reduce the cost of operation. The paper suggests motivators and barriers to the use of ICT in logistics in the health care industry.

Sustainable urban rail transit requires noise barriers. However, these barriers’ durability varies due to the differing aerodynamic impacts they experience. The purpose of this paper is to investigate the aerodynamic discrepancies of trains when they meet within two types of rectangular noise barriers: fully enclosed (FERNB) and semi-enclosed with vertical plates (SERNBVB). The research also considers the sensitivity of the scale ratio in these scenarios.

A 1:16 scaled moving model test analyzed spatiotemporal patterns and discrepancies in aerodynamic pressures during train meetings. Three-dimensional computational fluid dynamics models, with scale ratios of 1:1, 1:8 and 1:16, used the improved delayed detached eddy simulation turbulence model and slip grid technique. Comparing scale ratios on aerodynamic pressure discrepancies between the two types of noise barriers and revealing the flow field mechanism were done. The goal is to establish the relationship between aerodynamic pressure at scale and in full scale.

The aerodynamic pressure on SERNBVB is influenced by the train’s head and tail waves, whereas for FERNB, it is affected by pressure wave and head-tail waves. Notably, SERNBVB's aerodynamic pressure is more sensitive to changes in scale ratio. As the scale ratio decreases, the aerodynamic pressure on the noise barrier gradually increases.

A train-meeting moving model test is conducted within the noise barrier. Comparison of aerodynamic discrepancies during train meets between two types of rectangular noise barriers and the relationship between the scale and the full scale are established considering the modeling scale ratio.

Stiffened plates have been widely used in civil, marine, aerospace engineering. As a kind of thin-walled structure operating in complex environment, stiffened plates mostly undergo a variety of dynamic loads, which may sometimes result in large-amplitude vibration. Additionally, initial stresses and geometric imperfections are widespread in this type of structure. Furthermore, it is universally known that initial stresses and geometric imperfections may affect mechanical behavior of structures severely, particularly in dynamic analysis. Thus, the purpose of this paper is to study the stress variation rule of a stiffened plate during large-amplitude vibration considering initial stresses and geometric imperfections.

The initial stresses are represented in the form of initial bending moments applying to the stiffened plate, while the initial geometric imperfections are considered by means of trigonometric series, and they are assumed existing in the plate along the z-direction exclusively. Then, the dynamic equilibrium equations of the stiffened plate are established using Lagrange’s equation as well as aforementioned conditions. The nonlinear differential equations of motion are simplified as a two-degree-of-freedom system by considering 1:2 and 1:3 internal resonances, respectively, and the multiscale method is applied to solve the equations.

The influence of initial stresses on the plate, stresses during internal resonance is remarkable, while that is moderate for initial geometric imperfections. (Upon considering the existence of initial stresses or geometric imperfections, the stresses of motivated modes are less than the primary mode for both and internal resonances). The influence of bidirectional initial stresses on the plate’s stresses during internal resonance is more remarkable than that of unidirectional initial stresses. The coupled vibration in 1%3A2 internal resonance is fiercer than that in internal resonance.

Stiffened plates are widely used in engineering structures. However, as a type of thin-walled structure, stiffened plates vibrate with large amplitude in most cases owning to their complicated operation circumstance. In addition, stiffened plates usually contain initial stresses and geometric imperfections, which may result in the variation of their mechanical behavior, especially dynamical behavior. Based on the above consideration, this paper studies the nonlinear dynamical behavior of stiffened plates with initial stresses and geometrical imperfections under different internal resonances, which is the originality of this work. Furthermore, the research findings can provide references for engineering design and application.

In the knowledge-based view, knowledge is a valuable source of enterprise success. Its transfer through expatriates is a key mechanism in the value proposition of outward foreign direct investment by multinational enterprises (MNEs). Unfortunately, individuals are not always willing to share what they know. Expatriates are crucial players in knowledge transfer, and their knowledge-hiding behavior can significantly inhibit enterprise success. This paper thus aims to explore the patterns and antecedents of knowledge hiding, as well as the underlying mechanisms in the hiding process by expatriates within MNEs.

This paper focuses on expatriates assigned to emerging economies in Chinese MNEs. It is based on a systematic qualitative analysis of semi-structured interviews with 24 expatriates from 16 companies across 25 countries.

Not all knowledge hiding should be perceived as a negative behavior, as moderate rationalized hiding can fulfil a positive purpose. Antecedents of expatriates’ knowledge hiding were identified within a framework covering knowledge, individual, organizational and cultural features. Three main scenarios of knowledge-hiding process were also disclosed to illustrate the internal generative logic.

The comprehensive analysis of knowledge hiding presented in this paper enriches the existing literature on cross-border knowledge management and provides novel theoretical insights to better promote knowledge transfer by expatriates. A practical framework of knowledge transfer within MNEs is developed to guide the management of expatriates, even a broader spectrum of knowledge workers.

This purpose of this paper is to present a new approach of solving quantum control problem.

State‐transition‐matrix (STM) is used to solute quantum control problem.

The paper obtains the matrix representation for wave function, normalization, and some other quantum operators, and then gives the possible methods to establish the STM model and solve it.

Based on this, many tools of the widely used control theory can be adopted to denote or analyze the quantum system.