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The purpose of this paper is to develop a dual peg-in-hole insertion strategy. Dual peg-in-hole insertion is the most common task in manufacturing. Most of the previous work develop the insertion strategy in a two- or three-dimensional space, in which they suppose the initial yaw angle is zero and only concern the roll and pitch angles. However, in some case, the yaw angle could not be ignored due to the pose uncertainty of the peg on the gripper. Therefore, there is a need to design the insertion strategy in a higher-dimensional configuration space.

In this paper, the authors handle the insertion problem by converting it into several sub-problems based on the attractive region formed by the constraints. The existence of the attractive region in the high-dimensional configuration space is first discussed. Then, the construction of the high-dimensional attractive region with its sub-attractive region in the low-dimensional space is proposed. Therefore, the robotic insertion strategy can be designed in the subspace to eliminate some uncertainties between the dual pegs and dual holes.

Dual peg-in-hole insertion is realized without using of force sensors. The proposed strategy is also used to demonstrate the precision dual peg-in-hole insertion, where the clearance between the dual-peg and dual-hole is about 0.02 mm.

The sensor-less insertion strategy will not increase the cost of the assembly system and also can be used in the dual peg-in-hole insertion.

The theoretical and experimental analyses for dual peg-in-hole insertion are proposed without using of force sensor.

This paper aims to propose a deep learning model that can be used to expand the number of samples. In the process of manufacturing and assembling electronic components on the printed circuit board in the surface mount technology production line, it is relatively easy to collect non-defective samples, but it is difficult to collect defective samples within a certain period of time. Therefore, the number of non-defective components is much greater than the number of defective components. In the process of training the defect detection method of electronic components based on deep learning, a large number of defective and non-defective samples need to be input at the same time.

To obtain enough electronic components samples required for training, a method based on the generative adversarial network (GAN) to generate training samples is proposed, and then the generated samples and real samples are used to train the convolutional neural networks (CNN) together to obtain the best detection results.

The experimental results show that the defect recognition method using GAN and CNN can not only expand the sample images of the electronic components required for the training model but also accurately classify the defect types.

To solve the problem of unbalanced sample types in component inspection, a GAN-based method is proposed to generate different types of training component samples and then the generated samples and real samples are used to train the CNN together to obtain the best detection results.

The purpose of this paper is to solve temperature stress for bending beam with different moduli under different constraints subject to nonlinear temperature.

The equations of neutral axis position, normal stress, and displacement of bending beam with different moduli subjected to nonlinear temperature were derived based on different moduli elasticity theory. Meanwhile, iterative procedure was programmed to solve the nonlinear equations. The analytical solution can return back into the result of the same modulus theory, and the analytical solution was compared with finite element numerical solution. It shows that the analytical model proposed in this paper is reliable to use. Furthermore, the influence of different moduli characteristics on the temperature stress and deformation is discussed.

The mechanical behavior of the bending beam with different moduli subject to nonlinear temperature is quite different from the one that is subjected to force. The bending beam maybe exist two neutral axis, and the reasonable selection of tension modulus and compression modulus can improve the distribution of the normal stress and reduce the maximum tensile stress or the maximum compressive stress.

The crack produced by temperature stress will affect the integrity and the durability of the structure. The solution for temperature problem with different moduli theory is rarely reported at home and board. In view of this, this paper will do some exploratory research-temperature stress for bending beam with different moduli.

With the analysis of the causes of corruption, this study aims to investigate specific anti-corruption measures that can be implemented to reform the political system and the social climate of China.

This study examines 97 severe corruption cases of high-ranking officials in China, which occurred between 2012 and 2015. As this insinuates that both institutional and social corruption are major problems in China, the analysis delves into multiple facts of corruption, including different types, four primary underlying causes, and suggestions regarding the implementation of three significant governmental shifts that focus on investigation, prevention tactics and legal regulations.

China’s corruption is not only individual-based but also it has developed into institutional corruption and social corruption. Besides human nature and instinct, the causes of corruption can be organised into four categories, namely, social customs, social transitions, institutional designs and institutional operations. For the removed high-ranking officials, the formation of interest chains was an important underlying cause behind their corruption.

This study makes a significant contribution to the literature because this study provides a well-rounded approach to a complex issue by highlighting the significance of democracy and the rule of law as ways to regulate human behaviour to combat future corruption.

Conservation of green space is crucial to the sustainable urban development of China. Nanjing is a central city in the Yangtze River Delta cluster in eastern China. Owing to urbanization, the green spaces in this city have been affected significantly in terms of their scale and structure. Assessing such changes can provide a basis for environmental protection measures and sustainable development. Using Landsat remote-sensing image data from 1998 and 2007, we constructed a distribution map of the patches of green spaces in Nanjing, and analyzed and assessed the changes in scale and spatial layout of the green spaces using various landscape metrics including CA, PLAND, PD, MPS, LPI, NP, PD, TE, ED, MPI, and LSI. Coinciding with a sharp increase in urban population, the area of green spaces in Nanjing decreased by 27.06% between 1998 and 2007. The patches of green space increased by 39%, and the average area per patch decreased by about 47.52%. Green space patches were found to be unevenly distributed among the districts of Nanjing. In urban areas, significant numbers of such patches were found primarily in various types of parks, while in suburban areas, they were concentrated mainly in the hilly forestlands. Green spaces exhibited tendencies towards fragmentation, miniaturization, and discretization.

There are many challenges in the development of a digital library (DL) and their complexity can be approached effectively with a maturity model. In a maturity model, the features of a phenomenon are divided into different levels and at each level, they are first improved before going on to the improvement or realization of the next level. The purpose of this study is to design a digital library maturity model (DLMM) in Iran.

The DLMM was designed using a qualitative approach, meta-synthesis and the Delphi technique. First, the maturity features of a DL were identified by assessing 68 sources of study concerning DLs and maturity models using meta-synthesis. The maturity features were then validated by experts using the three-round Delphi technique. Finally, the experts were asked to categorize these features into the five levels of the capability maturity model (CMM) as the base model.

By analyzing these sources, three categories, seven concepts and 35 codes for the maturity features of a DL were identified. The majority of previous studies focused on the use of hardware/software systems as the backup and empowerment of DLs and the concept of DL content. The maturity features were then validated by experts using the three-round Delphi technique. Like the base model, DLMM has five levels, and most features were categorized into the third and fourth levels by the experts. Features such as human resources, needs assessment of DL and readiness to create a DL were included in the second level.

This work adds the concept of the maturity model to the literature of DLs.

The purpose of this paper is to fabricate and characterize osteochondral beta‐tricalcium phosphate/collagen scaffold with bio‐inspired design by ceramic stereolithography (CSL) and gel casting.

Histological analysis was applied to explore the morphological characteristics of the transitional structure between the bone and the cartilage. The acquired data were used to design biomimetic biphasic scaffolds, which include the bone phase, cartilage phase, and their transitional structure. The engineered scaffolds were fabricated from β‐TCP‐collagen by CSL and gel casting. The cartilage phase was added to the ceramic phase by gel‐casting and freeze drying.

The resulting ceramic scaffolds were composed of a bone phase with the following properties: 700‐900 μm pore size, 200‐500 μm interconnected pores size, 50‐65 percent porosity, fully interconnected, ∼12 Mpa compressive strength. A suitable binding force between cartilage phase and ceramic phase was achieved by physical locking that was created by the biomimetic transitional structure. Cellular evaluation showed satisfactory results.

This study is the first try to apply CSL to fabricate biological implants with β‐TCP and type‐I collagen. There are still some defects in the composition of the slurry and the fabrication process.

This strategy of osteochondral scaffold fabrication can be implemented to construct an osteochondral complex that is similar to native tissue.

The CSL technique is highly accurate, as well as biologically secure, when fabricating ceramic tissue engineering scaffolds and may be a promising method to construct hard tissue with delicate structures. The present strategy enhances the versatility of scaffold fabrication by RP.

Doctors' labour and medicines are special necessities for human survival and evolution. Since China launched the healthcare reform, the theoretical circles' discussions have not yet clarified the respective special properties of doctors' labour and medicines as goods and the internal relations between doctors' labour and medicines at the level of the theoretical basis.

Health is a prerequisite for people's all-round development, a precondition for economic and social development and the people's common aspiration. The all-round moderately prosperous society could not be achieved without people's all-round health.

The authors believe the socialist relation between doctors' labour and medicines with Chinese characteristics should be one that is people-oriented, and the corporatization of hospitals or the capitalization of doctors' labour should be avoided.

In this paper, the authors explore the particularity of doctors' labour, particularity of medicine production, circulation, consumption and the internal relations between doctors' labour and medicines by using the analytical approach of Marxist political economy while considering the special roles of doctor's labour and medicines in the reproduction of labour power and put forward the theoretical basis for the segregation of doctor's labour and medicines.

China holds a global monopoly of up to 97 percent for rare earth elements (REEs), which are indispensable for all kinds of twenty-first century high-tech applications. Since China has disrupted its exports and started discriminating between domestic and foreign demand, REEs have become a geostrategic resource. In March 2012, Japan, the USA and the European Union jointly filed a World Trade Organization dispute settlement case against China. The purpose of this paper is to elaborate why China implemented export quotas and tariffs on REEs and how the state is engaged in this sector domestically and abroad.

The analysis frames China as a “competition state” and connects domestic with foreign economic policy on REEs. It uses data from Chinese official documents and non-Chinese sources.

Better government control aims to consolidate the sector and lay the foundation for three other goals, namely: the establishment of integrated and innovative Chinese corporations that compete globally; the provision of incentives to attract high-tech foreign direct investment to China; and better environmental protection. China wants to climb the next step of the technological ladder to gain global economic leadership.

Global environmental protection in mining is eased. However, non-Chinese market players can only take advantage of new business opportunities when the prices remain high. Since REEs are of strategic importance, rising political interference and raw materials diplomacy will continue to distort markets and price building.

The paper connects domestic reregulation of China's rare earth sector with foreign policy goals (or “going in” and “going out”) using the competition state approach.