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The liquid lithium-lead breeding blanket in the international thermonuclear experimental reactor is one of the major international concerns and one of the potential conceptual designs for the fusion reactor.

Reduced activation ferritic-martensitic steels are being considered for application in future fusion technology as the relevant structural material, which will be in contact with the lithium-lead breeding material.

According to the test results, comprehensive evaluations of these findings have been performed to determine the wastage rates and mechanisms for the conceptual design of the fusion reactor.

From micro to macro, systematic cross-scale models are needed for the understanding of corrosion/wastage mechanisms in fusion reactor engineering applications.

The purpose of this paper is to study the recent work carried out in enhancing the properties of bitumen using nano-additives. Bitumen is a by-product obtained from the refining process of crude oil, therefore making it a diminishing product. It has been used by mankind since ages for various applications like sealants, binders, waterproof coatings and pavement construction material. It is a black viscous substance with adhesive nature.

Bitumen is used as a binding material because of its ability to become liquid when heated and become solid when cooled and thus used largely in construction of roads because of its unique properties. Low softening point of bitumen leads to melting of bitumen during summer and causes rutting of roads, whereas during winter it leads to cracking as bitumen acts brittle in nature during low temperature. Increasing global demand of bitumen has created gap between demand and supply which is increasing with the passage of time. Further modern life has created very high traffic volume and heavy load which makes it essential to improve performance of bitumen.

Research studies have reported that the thermal properties of bitumen are enhanced by using thermoplastic polymers such as styrene-butadiene-styrene, polyethylene and ethylene-vinyl acetate, rubber and bio waste etc.

This paper reviews various types of materials which have been used to improve the properties of bitumen and explores the possibility to synthesise bitumen composite materials with nanoadditives with improved structural, mechanical and thermal properties.

The purpose of this paper is to develop a potential nanoparticles lubricant additive for solving the problem of the insolubility and stable dispersity; the complex nanoparticles with core-shell structures are less studied in the field. Therefore, this paper determines novel complex nanoparticles and their tribological properties.

According to the conventional preparation method, the complex nanoparticle styrene/calcium borate (PS/O-CaB) was synthesized. The microstructures of the as-obtained samples were characterized by X-ray diffraction infrared spectroscopy and thermogravimetric analysis. Tribological properties of PS/O-CaB used as lubricating oil additive were evaluated on four-ball tribometer. The worn surface of the steel ball was investigated by a three-dimensional non-contact surface profilometer and X-ray photoelectron spectroscopy (XPS).

The results of the structure characteristic indicate two different crystalline forms, namely, Ca₂B₆O₁₁ and Ca₂B₂O₅, and the average size of calcium borate nanoparticles in PS/O-CaB is about 20-40 nm. Moreover, the good tribological properties are due to a wear resistance film containing both depositions and the tribochemical reaction products which comprise B2O3, FeB and Fe2O3.

Novel complex nanoparticles with core-shell structure (PS/O-CaB) were successfully prepared. Moreover, the PS/O-CaB shows excellent tribological capacity such as load-carrying, friction-reducing and antiwear property.

The concept of ‘multi-port gateway region’ has been introduced by Notteboom (2010) and has been applied to important seaport markets such as Europe and Asia. However, the dynamics and port development patterns in secondary multi-port gateway regions, such as the Black Sea region, have received far less attention in academic literature. An empirical application of established spatial and functional development models to such secondary port regions might substantiate the external validity of these models as these ports operate in a different spatial, economic and institutional environment.

The aim of the paper is to characterize the spatial dynamics of container ports of the Black Sea multi-port gateway regions by testing the validity of established spatial models on port system development. Furthermore, the expected future evolution path for port hierarchy in the Black Sea basin is discussed. By doing so, the paper assesses to what extent the Black Sea port region is following an ‘expected’ development path as portrayed in a number of port system development models, or alternatively, can be characterized as an atypical port system following its own development logic.

This paper aims to review the research status of fatigue behavior and fracture mechanism for C/C composites.

The fatigue behavior is related to many factors. The mechanical and physical properties were compared to evaluate the effect of fatigue under various experimental conditions, including different load type, loading frequency and stress ratio. Special attention is put on the high‐temperature fatigue research.

The strength has improved by fatigue loading. And most researchers considered that the weaken interface was the main reason for fatigue enhancement. However, the research on high‐temperature fatigue behavior is especially scarce.

This review provides a guideline on the current and future research on fatigue behavior of C/C composites.

Rapid developments in social networks and their usage in everyday life have caused an explosion in the amount of short electronic documents. Thus, the need to classify this type of document based on their content has a significant implication in many applications. The need to classify these documents in relevant classes according to their text contents should be interested in many practical reasons. Short-text classification is an essential step in many applications, such as spam filtering, sentiment analysis, Twitter personalization, customer review and many other applications related to social networks. Reviews on short text and its application are limited. Thus, this paper aims to discuss the characteristics of short text, its challenges and difficulties in classification. The paper attempt to introduce all stages in principle classification, the technique used in each stage and the possible development trend in each stage.

The paper as a review of the main aspect of short-text classification. The paper is structured based on the classification task stage.

This paper discusses related issues and approaches to these problems. Further research could be conducted to address the challenges in short texts and avoid poor accuracy in classification. Problems in low performance can be solved by using optimized solutions, such as genetic algorithms that are powerful in enhancing the quality of selected features. Soft computing solution has a fuzzy logic that makes short-text problems a promising area of research.

Using a powerful short-text classification method significantly affects many applications in terms of efficiency enhancement. Current solutions still have low performance, implying the need for improvement. This paper discusses related issues and approaches to these problems.

The purpose of this paper is to propose a two-degrees-of-freedom wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism based on spring, in order to improve the robot’s athletic ability, load capacity and rigidity, and to ensure the coordination of multi-modal motion.

First, based on the rotation transformation matrix and closed-loop constraint equation of the parallel trunk joint mechanism, the mathematical model of its inverse position solution is constructed. Then, the Jacobian matrix of velocity and acceleration is derived by time derivative method. On this basis, the stiffness matrix of the parallel trunk joint mechanism is derived on the basis of the principle of virtual work and combined with the deformation effect of the rope driving pair and the spring elastic restraint pair. Then, the eigenvalue distribution of the stiffness matrix and the global stiffness performance index are used as the stiffness evaluation index of the mechanism. In addition, the performance index of athletic dexterity is analyzed. Finally, the distribution map of kinematic dexterity and stiffness is drawn in the workspace by numerical simulation, and the influence of the introduced spring on the stiffness distribution of the parallel trunk joint mechanism is compared and analyzed. It is concluded that the stiffness in the specific direction of the parallel trunk joint mechanism can be improved, and the stiffness distribution can be improved by adjusting the spring elastic structure parameters of the rope-driven branch chain.

Studies have shown that the wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism based on spring has a great kinematic dexterity, load-carrying capacity and stiffness performance.

The soft-mixed structure is not mature, and there are few new materials for the soft-mixed mixture; the rope and the rigid structure are driven together with a large amount of friction and hindrance factors, etc.

It ensures that the multi-motion mode hexapod mobile robot can meet the requirement of sufficient different stiffness for different motion postures through the parallel trunk joint mechanism, and it ensures that the multi-motion mode hexapod mobile robot in multi-motion mode can meet the performance requirement of global stiffness change at different pose points of different motion postures through the parallel trunk joint mechanism.

The trunk structure is a very critical mechanism for animals. Animals in the movement to achieve smooth climbing, overturning and other different postures, such as centipede, starfish, giant salamander and other multi-legged animals, not only rely on the unique leg mechanism, but also must have a unique trunk joint mechanism. Based on the cooperation of these two mechanisms, the animal can achieve a stable, flexible and flexible variety of motion characteristics. Therefore, the trunk joint mechanism has an important significance for the coordinated movement of the whole body of the multi-sport mode mobile robot (Huang Hu-lin, 2016).

In this paper, based on the idea of combining rigid parallel mechanism with wire-driven mechanism, a trunk mechanism is designed, which is composed of four spring-based wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism in series. Its spring-based wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism can make the multi-motion mode mobile robot have better load capacity, mobility and stiffness performance (Qi-zhi et al., 2018; Cong-hao et al., 2018), thus improving the environmental adaptability and reliability of the multi-motion mode mobile robot.