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It is the basic task of burn therapy to cover the wound with self-healthy skin timely and effectively. However, for patients with extensive burns, autologous skin is usually insufficient, and allogenic or heterogeneous skin leads to strong immune response. It is vital to choose an appropriate treatment for deep extensive burns. Nowadays, the dermal substitute combined with bone marrow mesenchymal stem cells (BM-MSCs) is a prospective strategy for burn wound healing. Denatured acellular dermal matrix (DADM), as one of dermal substitutes, which prepared by burn skin discarded in escharotomy, not only maintains a certain degree of 3D structure of collagen, but also has good biocompatibility. In this study, the preparation method of DADM was improved and DADM was seeded with BM-MSCs. Then BM-MSCs-seeded DADM (DADM/MSCs) was implanted into mice cutaneous wound, and the effect of DADM/MSCs dermal substitute was assessed on skin regeneration. As a result, BM-MSCs survived well and DADM/MSCs scaffolds significantly promoted wound healing in terms of angiogenesis, re-epithelialization and skin appendage regeneration. DADM/MSCs scaffold may represent an alternative promising therapy for wound healing in deep extensive burns.

A pixel circuit is presented for active-matrix organic light-emitting diode (AMOLED) displays. The circuit contains five thin-film transistors (TFTs) and one capacitor (5T1C). In the circuit, by decreasing the driving TFT’s source voltage, the mobility-related discharge voltage is obtained. By inputting the data voltage in the programming stage, the circuit can compensate both threshold voltage variation and mobility variation using only one capacitor. Meanwhile, the circuit can prevent the current from flowing into the OLED when the OLED is not operated in the emission stage to prevent the image flicker. The circuit simulation results show that the OLED current error rate is lower than 5.7% when the threshold voltage varies ± 0 . 5 V , the error rate is lower than 5.5% when the mobility varies ± 30 % and the data voltage is above 0 V .

An intelligent toolpath (processing sequence) planning for fabricating aircraft structural parts is developed to obtain a minimum-length toolpath while maintaining the required machining time. The problem is first solved in the following ways. Firstly, an abstraction of the machining process is proposed to pick up the feed/retract points of each feature to be machined as the toolpath calculation basis. Secondly, the chaotic simulated annealing method is improved through storing the optimal solution, adding the control condition and selecting each parameter reasonably during the iteration of the algorithm so as to enhance its performance. What’s more, three solution-generating methods are used chaotically to obtain a better result. Lastly, the verification is conducted on four different aircraft structural parts, and the results prove that the proposed algorithm performs very well in terms of toolpath quality and computation time.

In order to enhance the NC programming efficiency and quality of aircraft structural parts (ASPs), an intelligent NC programming pattern driven by process schemes is presented. In this pattern, the NC machining cell is the minimal organizational structure in the technological process, consisting of an operation machining volume cell, and the type and parameters of the machining operation. After the machining cell construction, the final NC program can be easily obtained in a CAD/CAM system by instantiating the machining operation for each machining cell. Accordingly, how to automatically establish the machining cells is a key issue in intelligent NC programming. On the basis of the NC machining craft of ASP, the paper aims to make an in-depth research on this issue. Firstly, some new terms about the residual volume and the machinable volume are defined, and then, the technological process is modeled with a process scheme. Secondly, the approach to building the machining cells is introduced, in which real-time complement machining is mainly considered to avoid interference and overcutting. Thirdly, the implementing algorithm is designed and applied to the Intelligent NC Programming System of ASP . Finally, the developed algorithm is validated through two case studies.

This paper presents an effective method of NC machining cutting parameters optimization. For a given machine NC code, we use the secondary development tools provided by VERICUT software, the time series segmentation algorithm of sliding window technique, back stepping method for getting the feed rate based on the empirical formula and other methods to extract, process and optimize the cutting data. As a result of these, we can make the output power of the spindle reaching smooth and get the optimized processing code finally.