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Ti-Al composite plates have been used in aerospace and other important fields for specific purposes in recent years. However, relatively few studies have concentrated on Ti-Al additive manufacturing because during additive manufacturing process the local fusion and mixing of Ti/Al are inevitable. These areas where Ti and Al are mixed locally, especially interface, could easily generate high residual stresses and cracks. This study aims to manufacture Ti-Al functionally graded material and investigate the interaction of interface.

In this study, Ti6Al4V/AlSi10Mg functionally graded materials were fabricated by laser based directed energy deposition (L-DED) and a strategy using V interlayer to relieve interfacial stress was investigated.

The area between the two materials was divided into transition zone (TZ) and remelting zone (RZ). The phase distribution, microstructure and micro-Vickers hardness of the TZ and RZ were investigated. Typical intermetallic compounds (IMCs) such as TiAl3, Ti3Al and Ti5Si3 were found in both composites. The addition of V interlayer promoted the homogenization of IMCs near interface and led to the formation of new phases like V5Si3 and Al3V.

The solidification process near the interface of Ti-Al functionally graded material and the possible generation of different phases were described. The result of this paper proved the feasibility of manufacturing Ti-Al functionally graded material by L-DED.

In existing information retrieval models there are three different ways documents are represented for retrieval purposes: vectors of weights, collections of sentences and artificial neurons. Accordingly, retrieval depends on a similarity function, or means an inference, or is a spreading of activation. Relevancy is considered to be a critical modelling parameter which is either a priori or it is not treated at all. Assuming that relevancy may equally be an emergent entity, thus not requiring any a priori modelling, the paper proposes the Interaction Information Retrieval model in which documents are interconnected, queries and documents are treated in the same way, and in which retrieval is the result of the interconnection between query and documents. Algorithms and experiences gained with practical applications are presented. A theoretical mathematical formulation of this type of retrieval is also given.

To improve the accuracy of mapping of space‐borne three‐line array cameras.

Derivation of the mathematical model and the error model of the three‐line aerial triangulation, the creation of the simulation data, and the analysis and comparison of the simulating result error.

When using the photographs, which are acquired by adopting the traditional three‐line array cameras, to map without control, there exists the problem that the accuracy cannot satisfy the requirement.

Do not need the ground control points, and can realize the mapping without control. It is of practical application value to the mapping of stars such as the Moon, Mars.

By adding four small matrix CCDs to the traditional three‐line array cameras, and using the effect of the small matrix, controlling the location of the real photograph point, it can improve the accuracy.

Put forward the LMCCD concept of the combination of the three‐linear and the matrix cameras, and validate in theory.

Suggests that misunderstandings frequently occur when trying to understand Chinese language and culture, and so gives the implied meaning of various Chinese expressions and sayings such as greetings, thanks, respect, age, congratulations and taboo subjects.

To find the way to obtain the maximization of social welfare has been a focus of welfare economics. Pareto optimal conditions are usually considered a sufficient condition for the Welfare maximization, i.e., the first best solution. Under the mixed economy, however, it is almost impossible to reach this “Utopia” (pareto optimum) with institutional constraints such as monopoly and taxes. The second best solution then becomes the realistic and interesting problem few economists have paid attention to in the last two decades. In studying the second best theory, the following question arises: If a constraint, which prevents the satisfaction of at least one of the paretian conditons, is introduced into a general equilibrium system, which second best conditions depart from the corresponding paretian condition?

The purpose of this paper is to deal with the classification improvement of pollutant using WO3 gases sensors. To evaluate the discrimination capacity, some experiments were achieved using three gases: ozone, ethanol, acetone and a mixture of ozone and ethanol via four WO3 sensors.

To improve the classification accuracy and enhance selectivity, some combined features that were configured through the principal component analysis were used. First, evaluate the discrimination capacity; some experiments were performed using three gases: ozone, ethanol, acetone and a mixture of ozone and ethanol, via four WO3 sensors. To this end, three features that are derivate, integral and the time corresponding to the peak derivate have been extracted from each transient sensor response according to four WO3 gas sensors used. Then these extracted parameters were used in a combined array.

The results show that the proposed feature extraction method could extract robust information. The Extreme Learning Machine (ELM) was used to identify the studied gases. In addition, ELM was compared with the Support Vector Machine (SVM). The experimental results prove the superiority of the combined features method in our E-nose application, as this method achieves the highest classification rate of 90% using the ELM and 93.03% using the SVM based on Radial Basis Kernel Function SVM-RBF.

Combined features have been configured from transient response to improve the classification accuracy. The achieved results show that the proposed feature extraction method could extract robust information. The ELM and SVM were used to identify the studied gases.

La détermination des flux touristiques constitue une étape essentielle pour chiffrer d'une part, le nombre d'emplois nouveaux nécessaires afin de satisfaire la demande finale exogène qui s'accroîtra progressivement durant un horizon économique déterminé et pour préciser d'autre part, les investissements que requiert l'expansion des activités de service et du tourisme engendrés par un nouveau développement touristique.

This paper aims to assess the hydrodynamic lubrication of two opposing surfaces with identical pores having a semicircular profile. The surfaces are treated with more than one pore that allows clarification of whether there exists interaction between the pores.

A transient, spatial, one-dimensional model of surfaces with regular pores was developed and applied in the context of fluid lubrication. MATLAB software has been used.

Calculations show that a lubricating film between two surfaces with pores provides better hydrodynamic conditions in comparison to that on one surface with pores. It was also shown that the pores of one surface act as separate objects and can take into account only the interaction between the pores of the opposite surfaces. In addition, it was found that there are optimum values of the pore radii, gap and pore cell dimensions at which the bearing capacity of the film is maximal.

The computer program used for the pore parameter calculations provided the optimal lubrication.

This is the first study of the lubricating film hydrodynamic behavior of two opposite surfaces with pores having a semicircular profile.

The article's aim is to provide an overview of how care will be financed in the future in China as a consequence of changes in society.

The article is a descriptive review describing the responses and systems of funding that are being developed in China to address changes in care support structures and systems particularly in response to the single child policy and the impact of the increased financial aspirations of young Chinese people.

Traditional systems of support for elders have been weakened by changes in social structure and there is a need to develop new models of care and methods to finance this through both the state and insurance schemes. One consequence of change has been increasing numbers of elders living by themselves.

The one child policy has not only reduced the capacity of families to support their elders but has also caused an imbalance in the ratio of male to female children. It has now become essential to develop models of non‐familial support for elders to complement traditional systems.

The article provides an insight into the challenges facing China around elder care as a consequence of social policy change and increased economic mobility.

The purpose of this paper is to study the mechanism of efficient sputum excretion from the distal lung by using a tessellationally distal lung model with alveolar pores.

First, a two-dimensional tessellational composite structure of the bronchus, alveoli and alveolar pores (Kohn pore) is constructed with the tessellational splitting and fusion of regular hexagonal elements. Then, the level set method is used to study the effects of alveolar pores and their sizes, expiratory cycles and respiratory intensity.

The existence of alveolar pores is the prerequisite for sputum excretion, and there is an optimal size of alveolar pores for sputum excretion. Strong asymmetric respiration can break the reversibility of the flow at a low Reynolds number and causes significant net displacement of sputum. The expiratory cycle is negatively correlated with the net displacement of sputum. The respiratory intensity is positively correlated with the net displacement of sputum.

This research is helpful for understanding the complex sputum excretion process in diseases, such as pneumonia, and developing corresponding adjuvant therapy.