In recent years, with the combination of tissue engineering and additive manufacturing technologies, the possibility of fabricating scaffolds with porosity and complex structure has been improved. Since the properties of most biomaterial inks are influenced by temperature and thereby affect the quality of the scaffolds, a controlled printing environment is very important. This study focuses on temperature monitoring from the nozzle to the working platform. A compact heating jacket is developed to heat the needle and sense its temperature inside the nozzle. It makes it very different from common cartridge heating mechanisms. Moreover, a semi-closed printing environment composed of an air curtain and temperature circulation device is developed to create a stable cooling environment. It improves the uniformity of the work platform and increases by 50% the cooling time efficiency. To demonstrate the robustness for a wide range of temperatures, this study presents two experiments of printing two biomaterial inks at body and low temperatures, respectively.

This paper presents a novel test architecture that combines the advantages of high-quality deterministic scan-based test and low-cost built-in self-test. The main idea is to record (store) all required compressed test data in a novel scan chain structure, and extract and decompress them during testing. This requires a very high compression ratio to obtain a low test data volume, that is, smaller than the number of scan cells in the circuit under test. To achieve such a high compression ratio, we propose a novel compression method that combines broadcast scan as well as a tailored single-input compression architecture. We also utilize the concept of scan chain partitioning and clock gating to reduce the test time and test power. An on-chip test controller is employed to automatically generate all required control signals for the whole test procedure. This significantly reduces the requirements on external automatic test equipment. Experimental results show that our method is well suitable for multicore designs. For example, experiments on the 8-core open-source OpenSPARC T2 processor with 5.7M gates show that all required test data for 100% testable stuck-at fault coverage can be stored in just 59.4% of the scan cells of the processor. Experimental results for transition faults are also presented, which show that more identical cores are needed in order to store all test data for transition faults. We also discuss how to extend this paper to address fault diagnosis and engineering change order problems.