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Many countries have experienced, or are experiencing, urbanization. One such example is China. Even though the large‐scale rural‐urban migration seems chaotic on the surface, there are certain underlying forces driving individual decisions. The purpose of this paper is to provide some understanding of the relationship between human capital, migration, and occupational choices.

The paper starts with an overlapping generations model. Human capital plays various roles across different occupations – it does not affect the income of farmers, it affects income of workers linearly, and it has increasing returns in rural non‐farm business. The paper then derives income profiles for individuals with heterogeneous human capital, and finds the human capital thresholds of occupations. The paper calibrates the model to China, and simulates the model to answer two questions: how does an improving human capital distribution affect rural wages, quantities of migrants and return migrants? How does a fast‐growing urban wage rate affect rural wages, quantities of migrants and return migrants?

First, depending on the initial human capital level, policies aiming to enhance human capital may have different impacts on migration. If the initial human capital level is low, these policies will yield more permanent migrants; on the contrary, if the initial human capital is at a relatively high level, then a shrinking permanent migrant class with a growing entrepreneur class can be expected. This results in an inverted U‐shaped relation between the initial human capital level and the size of the permanent migrant class. Second, even though the non‐farm business of return migrants helps raise rural wages, the income inequality between rural and urban areas is not eliminated and migration is persistent. Third, borrowing constraints limit the size of rural non‐farm businesses and slow down the development of rural industry. The fourth and final point is that, migration costs discourage labor mobility and reduce the quantities of both permanent migrants and entrepreneurs.

This is an original paper on this subject.

This paper aims to propose a method for better discovering topic evolution path and semantic relationship from the perspective of patent entity extraction and semantic representation. On the one hand, this paper identifies entities that have the same semantics but different expressions for accurate topic evolution path discovery. On the other hand, this paper reveals semantic relationships of topic evolution for better understanding what leads to topic evolution.

Firstly, a Bi-LSTM-CRF (bidirectional long short-term memory with conditional random field) model is designed for patent entity extraction and a representation learning method is constructed for patent entity representation. Secondly, a method based on knowledge outflow and inflow is proposed for discovering topic evolution path, by identifying and computing semantic common entities among topics. Finally, multiple semantic relationships among patent entities are pre-designed according to a specific domain, and then the semantic relationship among topics is identified through the proportion of different types of semantic relationships belonging to each topic.

In the field of UAV (unmanned aerial vehicle), this method identifies semantic common entities which have the same semantics but different expressions. In addition, this method better discovers topic evolution paths by comparison with a traditional method. Finally, this method identifies different semantic relationships among topics, which gives a detailed description for understanding and interpretation of topic evolution. These results prove that the proposed method is effective and useful. Simultaneously, this method is a preliminary study and still needs to be further investigated on other datasets using multiple emerging deep learning methods.

This work provides a new perspective for topic evolution analysis by considering semantic representation of patent entities. The authors design a method for discovering topic evolution paths by considering knowledge flow computed by semantic common entities, which can be easily extended to other patent mining-related tasks. This work is the first attempt to reveal semantic relationships among topics for a precise and detailed description of topic evolution.

The purpose of this paper is to explore the correlations among entrepreneurial environment, market-oriented strategies, and entrepreneurial performance.

Entrepreneurial environment is measured by institutional environment and industrial environment. A survey of 176 large Chinese automobile firms is conducted. The structural equation model is applied to perform analysis.

The uncertainty of the institutional environment is positively related with market-oriented strategies and market-oriented strategies are positively related with firms’ performance. The stronger the uncertainty of the industrial environment is, the larger impact that market-oriented strategies have on firms’ performance will be. There is no distinct positive relationship between the uncertainty of industrial environment and firms’ market-oriented strategies. The hypothesis, that the stronger the uncertainty of institutional environments is, the larger the impact that market-oriented strategies will be on firms’ performance, is not supported.

In terms of research design, this paper does not select survey samples randomly. This paper only takes institutional and industrial environments into consideration while the environmental characteristics are omitted.

This paper expands entrepreneurship research by integrating previous studies. Findings in this paper are helpful for firms in emerging countries to implement “going abroad strategies,” to start up new businesses in other countries, and to achieve the goals of improving competitiveness and integrating with international firms.

The weft-knitted two-side jacquard fabric has the characteristics of complicated design principle and hard technical design. The purpose of this paper is to realize the computer-aided design of weft-knitted two-side jacquard fabric, and provide a certain reference for the development of this type of fabric.

The weft-knitted two-side jacquard fabric is divided into weft-knitted two-side similar pattern jacquard fabric and weft-knitted two-side independent pattern jacquard fabric. In order to achieve the purpose of this study, firstly, the structural characteristic of weft-knitted two-side jacquard fabric is analyzed. Then, the design principle of weft-knitted two-side jacquard fabric is studied. Next, the technical model of weft-knitted two-side jacquard fabric is established. Finally, the CAD flow chart of weft-knitted two-side jacquard fabric is proposed to realize the rapid product development.

Based on the above method, through the development example of weft two-side similar pattern jacquard fabric and weft two-side independent pattern jacquard fabric, the computer-aided design of the weft two-side jacquard fabric is verified.

Because of limited research studies, three-dimensional computer-aided design of weft-knitted two-side jacquard fabric loop structure will be studied in the further research, and the technical design speed needs to be improved to meet the needs of large patterns and positioning patterns.

The computer-aided design of weft-knitted two-side jacquard fabric will offer a certain reference for product development, technical principles, performance research and computer simulation for the in-depth study of the fabric.

The computer-aided design of weft-knitted two-side jacquard fabric will simplify the fabric design process and improve the efficiency of new fabric development, and provide the industries a time-saving and cost-saving approach for new fabrics development.

The author analyzes the structural characteristic of the fabric by the physical fabric, summarizes design principle of the fabric through production process, uses mathematical methods to establish a three-dimensional technical model of the fabric, and proposes the CAD flow chart of weft-knitted two-side jacquard fabric, which has good theoretical significance and practice of weft-knitted two-side jacquard fabric.

This study aims to control the oxidation resistance of Co-based deformed superalloys by adding trace elements Hf and Si.

The effects and mechanism of trace elements Hf and Si on the oxidation behavior of Co-Ni-Al-W-based forged superalloys were investigated by cyclic oxidation at 900°C.

The results show that the addition of trace elements Hf and Si does not affect the type of surface oxides of Co-Ni-based superalloys, and the oxidation layers of the alloys are TiO₂, spinel, Cr₂O₃, TaTiO₄, Al₂O₃ and TiN from outside to inside. However, the addition of elements can affect the activity of Cr and Ti elements; decrease the formation of TiO₂ and TaTiO₄ layers, which are harmful to the oxidation performance; and then improve the oxidation resistance of the alloy.

The relevant research results can not only optimize the microalloying element content of Co-Ni-Al-W-based superalloys, but also provide a new perspective for the composition optimization design of superalloys.