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It is a challenge to print a model with the size that is larger than the working volume of a three-dimensional (3D) printer. The purpose of this paper is to present a feasible approach to divide a large model into small printing parts to fit the volume of a printer and then assemble these parts into the final model.

The proposed approach is based on the skeletonization and the minima rule. The skeleton of a printing model is first extracted using the mesh contraction and the principal component analysis. The 3D model is then partitioned preliminarily into many smaller parts using the space sweep method and the minima rule. The preliminary partition is finally optimized using the greedy algorithm.

The skeleton of a 3D model can effectively represent a simplified version of the geometry of the 3D model. Using a model’s skeleton to partition the model is an efficient way. As it is generally desirable to have segmentations at concave creases and seams, the cutting position should be located in the concave region. The proposed approach can partition large models effectively to well retain the integrity of meaningful parts.

The proposed approach is new in the rapid prototyping field using the model skeletonization and the minima rule. Based on the authors’ knowledge, there is no method that concerns the integrity of meaningful parts for partitioning. The proposed method can achieve satisfactory results by the integrity of meaningful parts and assemblability for most 3D models.

This study attempts to document the impact of financial leverage on corporate innovation in the Chinese nonfinancial public firms listed on Shenzhen and Shanghai stock exchanges.

The firm-level data are collected from CSMAR database for ten years, ranging from 2007 to 2016. The authors have employed the panel fixed effects model and further system GMM approach for analysis. The sample is segregated on the basis of state (SOE) and nonstate ownership (NSOE) to check for the diverse effects. In total, three different proxies of financial leverage are used to unearth the varying impact of short-time and long-term leverage separately. Further, corporate innovation is divided into input innovation (R&D/Sales and R&D/Assets) and output innovation (patents and inventions).

The results suggest that financial leverage is detrimental to the input innovation while conducive for the output innovation when measured by the number of patents. Contrarily, leverage has a negative influence over the output innovation when measured by the number of inventions. This implies that leverage is more damaging for the highest form of innovativeness (inventions) in China. Input innovation is more sensitive to the changes in long-term leverage versus short-term leverage. Further, the authors find that innovation in SOEs is more sensitive to the changes in the leverage as compared to the NSOEs. The results are free from the threat of endogeneity and identification problems, as reported by the system GMM model.

The authors did not segregate the sample on the basis of industry/sector.

The firms pursuing a strategy of radical innovation should try to keep their debt levels lower in order to achieve a higher innovation performance. Although, a rise in the leverage may mean an increased access to finance for a firm but such an access comes at a cost in the form of damage to the corporate innovation. However, increased debt financing may not be so bad for the firms that want to achieve a moderate and not the highest level of innovation. Such firms can produce recurring and synergic effects with debt financing and moderate innovation, once they achieve a level of innovation performance that satisfies their financiers.

To the best of authors’ knowledge, this is probably the first study to check the impact of firm-level financial leverage on both input and output innovation in the Chinese public-listed nonfinancial firms' panel data perspective till now.

The purpose of this paper is to apply analysis of public discourses on Ze Xiao to explore and interpret the power relationships shaping inequality in admission to public junior high schools in urban China.

This study first introduces the rise of Ze Xiao as an educational phenomenon in China. It then elucidates power relationships in public school admission by analyzing continuities and changes in stakeholders’ interaction in public school admission. It concludes by discussing educational reform for equal public school admission in urban China. Data were collected from written and spoken texts about public school admission, including newspaper articles from the 1980s to the 2000s, policy documents and interviews with relevant stakeholders.

Findings demonstrate that multi-layered power relationships caused diverse inequalities in admission to public secondary education in urban China. These are represented by political and institutional privileges and an imbalance in education development during the social transition from a profit-driven approach in the 1990s to a balance-centered one after 2000. Arguably, there is a necessity to further promote a systematic reform to terminate the privileges and imbalance for an equal and balanced public secondary education in urban China post-2015.

This study attempts to make a contribution toward reconstructing the meaning of inequality in admission to public junior high schools in urban areas by revealing the power relationships among stakeholders constituted through their interactions in public education during the different stages of socio-economic development in urban China.

Due to the inability to directly apply an intra-oral image with esthetic restoration to restore tooth shape in the computer-aided design system, this paper aims to propose a method that can use two-dimensional contours obtained from the image for the three-dimensional dental mesh model restoration.

First, intra-oral image and smiling image are taken from the patient, then teeth shapes of the images are designed based on esthetic restoration concepts and the pixel coordinates of the teeth’s contours are converted into the vertex coordinates in the three-dimensional space. Second, the dental mesh model is divided into three parts – active part, passive part and fixed part – based on the teeth’s contours of the mesh model. Third, the vertices from the teeth’s contours of the dental model are matched with ones from the intra-oral image and with the help of matching operation, the target coordinates of each vertex in the active part can be calculated. Finally, the Laplacian-based deformation algorithm and mesh smoothing algorithm are performed.

Benefitting from the proposed method, the dental mesh model with esthetic restoration can be quickly obtained based on the intra-oral image that is the result of doctor-patient communication. Experimental results show that the quality of restoration meets clinical needs, and the typical time cost of the method is approximately one second. So the method is both time-saving and user-friendly.

The method provides the possibility to design personalized dental esthetic restoration solutions rapidly.