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A number of automated tools will be required for the purpose of enabling efficient services in air traffic control. The purpose of this paper is to devise an optimal flight trajectory search method that optimizes airspace system efficiency for 3D space in the presence of uncertainties.

This paper put forward an optimization model for generating applicable solutions of multi-aircraft conflict resolution problem, and the solution is based on the principle of optimality.

The conflict resolution problem between multiple aircraft can be described by spatial discretization, and the approach taken digitizes the 3D space into a grid of nodes.

The simulation examples are given to illustrate the validity of trajectory search model and stress on the impact of different system parameters.

Realistic constraints that are convenient to operate are incorporated in the system model, and the results show that it can provide reliable decision-making for conflict avoidance.

The purpose of this research is to examine the type of online reviews (review timeliness, review quantity, and review valence) and its relationship toward online purchase intention for electronic products among millennials in Malaysia.

The quantitative approach and simple random sampling methodology were used in this research. Data were gathered through a survey instrument, and the partial least squares structural equation modeling (PLS-SEM) technique was subsequently applied to 215 responses. The model explained 36.3 percent variation of the major constructs in relation to online purchase intention of electronic products amongst Malaysian millennials.

Review timeliness is the most influential online reviews element towards Malaysian millennials' online purchase intention for electronic products.

This research project has provided the researcher and marketers with more clarity into the area of online purchase intention for electronic products, which is a volatile and dynamic area with continuous uncertainty.

In this study, suggestions on the protection and development of marine resources, sea area use and management, improvement of laws and regulations, monitoring of marine resources and impact assessment of marine environment are put forward.

Literature research method.

A major factor contributing to the decline in fishery resources is excessive fishing. At present, there are many problems to be solved in the exploitation and utilization of marine mineral resources in China. The pollution problem of marine tourism resources is becoming increasingly serious. Overmining of coastal sea resources has led to planning and management failures.

This paper discusses the current situation of marine resource exploitation and protection in China and analyzes the reasons for excessive resource exploitation from three aspects of marine concept, laws and regulations and marine management.

This paper aims to study the impact of transient velocity changes on sealing performance during reciprocating sealing processes.

Establish a model of transient mixed lubrication, solve the transient Reynolds equation, consider the effect of temperature rise at the seal interfaces, and determine the behavior of the seal interfaces, such as film thickness and fluid pressure. Evaluation with friction and leakage rate, calculate the variation of sealing performance with reciprocating velocity under different working conditions, and verify it through bench experiments.

Within a reciprocating stroke, the frictional force decreases with increasing velocity, and the frictional force of the outstroke is greater than that of the instroke; at the time of the stroke transition, the fluid pressure is smallest and the rough peak contact pressure is greatest. At present, the dynamic pressure effect of fluids is the largest, and the friction force also increases, which increases the risk of material wear and failure. Friction and leakage increase with increasing pressure and root mean square roughness. As temperature increases, friction increases and leakage decreases. In studying the performance variations of seal components through a reciprocating sealing experiment, it was found that the friction force decreases with increasing velocity, which is consistent with the calculated results and more similar to the calculated results considering the temperature rise.

This study provides a reference for the study of transient sealing performance.

In this study, the authors performed a numerical investigation on the heating of a hot cathode with a conical tip by atmospheric arc, taking into account of the two temperature sheath effect for the first time.

The Schottky effect at cathode surface is considered, which is based on the analytic solution of a one-dimensional sheath model. The unified model allows one to predict the cathode-plasma heat transfer.

The total heat flux to cathode surface is smaller than its components’ heat flux due to electron back diffusion is as large as that due to ion flux with the increase of cathode length the total heat transported to the cathode body has an obvious decrease.

It is found that two kinds of solution exist for the cathode with a 140° conical tip; however, only one stable solution exists when the conical angle is reduced to 130°.

This paper aims to investigate the effect of frictional heat on the wear of high-speed rotary lip seals in engines.

In this research paper, the authors focus on the high-speed rotating lip seal of aircraft engines. Using the hybrid lubrication theory, a thermal-fluid-solid coupled numerical simulation model is established to investigate the influence of parameters such as contact pressure distribution, temperature rise and leakage rate on the sealing performance under different operating conditions. By incorporating the Rhee wear theory and combining simulation results with experimental data, a method for predicting the wear of the rotating seal lip profile is proposed. Experimental validation is conducted using a high-speed rotating test rig.

The results indicate that as the speed increases, the rise in frictional heat leads to a decrease in the sealing performance of the lip seal contact region. The experimental results show a similar trend to the numerical simulation results, and considering the effect of frictional heat, the predicted wear of the lip seal profile aligns more closely with the actual wear curve. This highlights the importance of considering the influence of frictional heat in the analysis of rotating seal mechanisms.

This study provides a reference for the prediction of wear profiles of engine high-speed rotary lip seals.

Quantum key distribution (QKD) is a technology, based on the quantum laws of physics, rather than the assumed computational complexity of mathematical problems, to generate and distribute provably secure cipher keys over unsecured channels. The authors are using this concept of QKD for the online banking systems. The paper aims to discuss these issues.

In order to function properly, any system using QKD needs to transport both quantum and classical data from a specified source to a specified destination, resolve competing requests for shared hardware, and manage shared keys between neighboring trusted nodes via a multi-hop mechanism. In this paper the authors are going to explain the transmission and control system for QKD implementation in online banking systems.

This paper presents the transmission and system control of QKD for online banking system is feasible under specific conditions outside a laboratory. Above, the authors have shown the research on the QKD based online banking systems. Though the current researches are focused on QKD systems for online banking systems, the techniques discussed can be applied to other quantum information processing involving photons. Combination with other efforts that are not mentioned here, such as entangled-photon-sources, single photon sources, two-qubit gates, and so on, will provide a rigid foundation for future quantum information technologies.

Recognizing the importance of online access as one of the vehicles for the development of cheaper, faster and more reliable services there are areas of improvement where all involved parties should endeavor to improve toward the deployment of services without unnecessary or excessive risks. This improvement applies to both retail and commercial customers and does not endorse any particular technology.